Aging is one of the most significant health challenges worldwide and is a primary cause of chronic diseases and physiological decline.Among the myriad changes that occur with aging,alterations in adipose tissue distri...Aging is one of the most significant health challenges worldwide and is a primary cause of chronic diseases and physiological decline.Among the myriad changes that occur with aging,alterations in adipose tissue distribution and function have gained considerable attention because of their profound impact on metabolic health and overall well-being.Subcutaneous adipose tissue(SAT)and visceral adipose tissue(VAT)are the two major depots of white adipose tissue,each with distinct roles in metabolism and health.Understanding the characteristics and underlying mechanisms of SAT and VAT is crucial for elucidating the aging process and developing strategies to promote healthy aging.This review focuses on delineating and analyzing the characteristics and intrinsic mechanisms underlying the aging of subcutaneous and visceral adipose tissue during the aging process,which can contribute to a better understanding of the aging process and enhance healthy aging.展开更多
BACKGROUND Evidence suggests inflammatory mesenteric fat is involved in post-operative recurrence(POR)of Crohn’s disease(CD).However,its prognostic value is INTRODUCTION Crohn’s disease(CD)is a debilitating chronic ...BACKGROUND Evidence suggests inflammatory mesenteric fat is involved in post-operative recurrence(POR)of Crohn’s disease(CD).However,its prognostic value is INTRODUCTION Crohn’s disease(CD)is a debilitating chronic immune-mediated inflammatory disease(IMID)of the gastrointestinal tract that is increasing in incidence and prevalence globally[1].CD patients often undergo surgery for disease-related complic-ations and/or medically refractory disease.Unfortunately,surgery is not curative,and many patients develop post-operative recurrence(POR)of CD with a significant proportion eventually requiring additional surgeries.With advances in early detection and therapeutics,the contemporary 10-year risk of surgery has improved from 50%to 26%,but the risk of recurrent surgery has remained unchanged at 30%,suggesting a need to improve post-operative management strategies[2].Presently,there are two accepted strategies to mitigate POR,but each have potential limitations.Firstly,patients start early post-operative pharmacologic prophylaxis within 4-6 wk after surgery.This strategy can potentially overtreat a subset of patient who may not develop long-term disease recurrence off therapy.Consequently,these patients are at risk of medication-related adverse events and the direct and indirect costs associated with therapy with little or no benefit[3].The second strategy is performing early colonoscopy within 6-12 months after surgery and escalating therapy based on FOOTNOTES Author contributions:Gu P is the guarantor of the article and was involved in concept and design,data collection,statistical analysis,drafting of manuscript,and final approval of manuscript;Dube S and Choi SY were involved in statistical analysis,drafting of the manuscript,and final approval of manuscript;Gellada N,Win S,Lee YJ and Yang S were involved in the data collection,drafting of the manuscript,and final approval of manuscript;Haritunians T and Li D were involved in data analysis and interpretation,drafting of manuscript and final approval of manuscript;Melmed GY,Yarur AJ,Fleshner P,Kallman C and Devkota S were involved in study concept and design,data interpretation,drafting of manuscript and final approval of manuscript;Vasiliauskas EA,Bonthala N,Syal G,Ziring D and Targan SR were involved in data interpretation,drafting of manuscript and final approval of manuscript;Rabizadeh S was involved in study concept and design,drafting of manuscript and final approval of manuscript;McGovern DPB was involved in concept and design,statistical analysis,drafting of manuscript and final approval of manuscript.展开更多
Acute pancreatitis is a common systemic inflammatory disease, manifested by a spectrum of severity, ranging from mild in the majority of patients to severe acute pancreatitis. Patients with severe acute pancreatitis s...Acute pancreatitis is a common systemic inflammatory disease, manifested by a spectrum of severity, ranging from mild in the majority of patients to severe acute pancreatitis. Patients with severe acute pancreatitis suffer from severe local and systemic complications and organ failure, leading to a poor prognosis. The early recognition of the severe condition is important to improve prognosis. Obesity has risen in tandem with an increase in the severity of acute pancreatitis in recent years. Studies have revealed that adipose tissue, particularly visceral adipose tissue is associated with the prognosis of acute pancreatitis. This review discussed the role of visceral adipose tissue in obese patients with acute pancreatitis and explored the possible mechanism involved.展开更多
Background Brown adipose tissue(BAT)is known to be capable of non-shivering thermogenesis under cold stimulation,which is related to the mortality of animals.In the previous study,we observed that goat BAT is mainly l...Background Brown adipose tissue(BAT)is known to be capable of non-shivering thermogenesis under cold stimulation,which is related to the mortality of animals.In the previous study,we observed that goat BAT is mainly located around the kidney at birth,and changes to white adipose tissue(WAT)in the perirenal adipose tissue of goats within one month after birth.However,the regulatory factors underlying this change is remain unclear.In this study,we systematically studied the perirenal adipose tissue of goat kids in histological,cytological,and accompanying molecular level changes from 0 to 28 d after birth.Results Our study found a higher mortality rate in winter-born goat kids,with goat birthing data statistics.Then we used thermal imaging revealing high temperature in goat hips at postnatal 0 d and gradually decrease during 28 d.This is consistent with the region of perirenal BAT deposition and highlights its critical role in energy expenditure and body temperature regulation in goat kids.Additionally,we found a series of changes of BAT during the first 28 d after birth,such as whitening,larger lipid droplets,decreased mitochondrial numbers,and down-regulation of key thermogenesis-related genes(UCP1,DIO2,UCP2,CIDEA,PPARGC1a,C/EBPb,and C/EBPa).Then,we used RNA-seq found specific marker genes for goat adipose tissue and identified 12 new marker genes for BAT and 10 new marker genes for WAT of goats.Furthermore,12 candidate genes were found to potentially regulate goat BAT thermogenesis.The mechanism of the change of this biological phenomenon does not involve a large-scale death of brown adipocytes and subsequent proliferation of white adipocytes.While apoptosis may play a limited role,it is largely not critical in this transition process.Conclusions We concluded that perirenal BAT plays a crucial role in thermoregulation in newborn goat kids,with notable species differences in the expression of adipose tissue marker genes,and we highlighted some potential marker genes for goat BAT and WAT.Additionally,the change from BAT to WAT does not involve a large-scale death of brown adipocytes and subsequent proliferation of white adipocytes.展开更多
Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is no...Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body metabolism.Exosomes are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(AT Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine mechanisms.However,the roles of AT Exos in crosstalk with metabolic organs remain to be fully elucidated.In this review,we summarize the latest research progress on the role of AT Exos in the regulation of metabolic disorders.Moreover,we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.展开更多
Background:Visceral adipose tissue(VAT)has been linked to the severe acute pancreatitis(SAP)prognosis,although the underlying mechanism remains unclear.It has been reported that pyroptosis worsens SAP.The present stud...Background:Visceral adipose tissue(VAT)has been linked to the severe acute pancreatitis(SAP)prognosis,although the underlying mechanism remains unclear.It has been reported that pyroptosis worsens SAP.The present study aimed to verify whether mesenteric adipose tissue(MAT,a component of VAT)can cause secondary intestinal injury through the pyroptotic pathway.Methods:Thirty-six male Sprague Dawley(SD)rats were divided into six different groups.Twelve rats were randomly divided into the SAP and control groups.We monitored the changes of MAT and B lymphocytes infiltration in MAT of SAP rats.Twelve SAP rats were injected with MAT B lymphocytes or phosphate buffer solution(PBS).The remaining twelve SAP rats were first injected with MAT B lymphocytes,and then with MCC950(NLRP3 inhibitor)or PBS.We collected blood and tissue samples from pancreas,gut and MAT for analysis.Results:Compared to the control rats,the SAP group showed inflammation in MAT,including higher expression of tumor necrosis factor(TNF-α)and interleukin-6(IL-6),lower expression of IL-10,and histological changes.Flow cytometry analysis revealed B lymphocytes infiltration in MAT but not T lymphocytes and macrophages.The SAP rats also exhibited intestinal injury,characterized by lower expression of zonula occludens-1(ZO-1)and occludin,higher levels of lipopolysaccharide and diamine oxidase,and pathological changes.The expression of NLRP3 and n-GSDMD,which are responsible for pyroptosis,was increased in the intestine of SAP rats.The injection of MAT B lymphocytes into SAP rats exacerbated the inflammation in MAT.The upregulation of pyroptosis reduced tight junction in the intestine,which contributed to the SAP progression,including higher inflammatory indicators and worse histological changes.The administration of MCC950 to SAP+MAT B rats downregulated pyroptosis,which subsequently improved the intestinal barrier and ameliorated inflammatory response of SAP.Conclusions:In SAP,MAT B lymphocytes aggravated local inflammation,and promoted the injury to the intestine through the enteric pyroptotic pathway.展开更多
During the periparturient period, dairy cows exhibit negative energy balance due to limited appetite and increased energy requirements for lactogenesis. The delicate equilibrium between energy availability and expendi...During the periparturient period, dairy cows exhibit negative energy balance due to limited appetite and increased energy requirements for lactogenesis. The delicate equilibrium between energy availability and expenditure puts cows in a state of metabolic stress characterized by excessive lipolysis in white adipose tissues(AT), increased production of reactive oxygen species, and immune cell dysfunction. Metabolic stress, especially in AT, increases the risk for metabolic and inflammatory diseases. Around parturition, cows are also susceptible to endotoxemia. Bacterial-derived toxins cause endotoxemia by promoting inflammatory processes and immune cell infiltration in different organs and systems while impacting metabolic function by altering lipolysis, mitochondrial activity, and insulin sensitivity. In dairy cows, endotoxins enter the bloodstream after overcoming the defense mechanisms of the epithelial barriers, particularly during common periparturient conditions such as mastitis, metritis, and pneumonia, or after abrupt changes in the gut microbiome. In the bovine AT, endotoxins induce a pro-inflammatory response and stimulate lipolysis in AT, leading to the release of free fatty acids into the bloodstream. When excessive and protracted, endotoxin-induced lipolysis can impair adipocyte's insulin signaling pathways and lipid synthesis. Endotoxin exposure can also induce oxidative stress in AT through the production of reactive oxygen species by inflammatory cells and other cellular components. This review provides insights into endotoxins' impact on AT function, highlighting the gaps in our knowledge of the mechanisms underlying AT dysfunction, its connection with periparturient cows' disease risk, and the need to develop effective interventions to prevent and treat endotoxemia-related inflammatory conditions in dairy cattle.展开更多
In this letter,we commented on the article by Wu et al.We examined the interactions between mesenteric adipose tissue,creeping fat,and gut microbiota in Crohn’s disease(CD),a condition marked by chronic gastrointesti...In this letter,we commented on the article by Wu et al.We examined the interactions between mesenteric adipose tissue,creeping fat,and gut microbiota in Crohn’s disease(CD),a condition marked by chronic gastrointestinal inflammation with a rising global incidence.The pathogenesis of CD involves complex genetic,environmental,and microbial factors.Dysbiosis,which is an imbalance in gut microbial communities,is frequently observed in CD patients,highlighting the pivotal role of the gut microbiota in disease progression and the inflammatory response.Recent studies have shown that mesenteric adipose tissue and creeping fat actively contribute to inflammation by producing proinflammatory cytokines.The relationship between creeping fat and altered microbiota can shift from a potentially protective role to one that encourages bacterial translocation,further complicating disease management.Recent research has suggested that fecal microbiota transplantation could help restore microbial balance,offering a promising therapeutic strategy to improve clinical disease response.展开更多
BACKGROUND The mechanism of improvement of type 2 diabetes after duodenal-jejunal bypass(DJB)surgery is not clear.AIM To study the morphological and functional changes in adipose tissue after DJB and explore the poten...BACKGROUND The mechanism of improvement of type 2 diabetes after duodenal-jejunal bypass(DJB)surgery is not clear.AIM To study the morphological and functional changes in adipose tissue after DJB and explore the potential mechanisms contributing to postoperative insulin sensitivity improvement of adipose tissue in a diabetic male rat model.METHODS DJB and sham surgery was performed in a-high-fat-diet/streptozotocin-induced diabetic rat model.All adipose tissue was weighed and observed under microscope.Use inguinal fat to represent subcutaneous adipose tissue(SAT)and mesangial fat to represent visceral adipose tissue.RNA-sequencing was utilized to evaluate gene expression alterations adipocytes.The hematoxylin and eosin staining,reverse transcription-quantitative polymerase chain reaction,western blot,and enzyme-linked immunosorbent assay were used to study the changes.Insulin resistance was evaluated by immunofluorescence.RESULTS After DJB,whole body blood glucose metabolism and insulin sensitivity in adipose tissue improved.Fat cell volume in both visceral adipose tissue(VAT)and SAT increased.Compared to SAT,VAT showed more significantly functional alterations after DJB and KEGG analysis indicated growth hormone(GH)pathway and downstream adiponectin secretion were involved in metabolic regulation.The circulating GH and adiponectin levels and GH receptor and adiponectin levels in VAT increased.Cytological experiment showed that GH stimulated adiponectin secretion and improve insulin sensitivity.CONCLUSION GH improves insulin resistance in VAT in male diabetic rats after receiving DJB,possibly by increasing adiponectin secretion.展开更多
BACKGROUND Obesity has become a serious public health issue,significantly elevating the risk of various complications.It is a well-established contributor to Heart failure with preserved ejection fraction(HFpEF).Evalu...BACKGROUND Obesity has become a serious public health issue,significantly elevating the risk of various complications.It is a well-established contributor to Heart failure with preserved ejection fraction(HFpEF).Evaluating HFpEF in obesity is crucial.Epicardial adipose tissue(EAT)has emerged as a valuable tool for validating prognostic biomarkers and guiding treatment targets.Hence,assessing EAT is of paramount importance.Cardiovascular magnetic resonance(CMR)imaging is acknowledged as the gold standard for analyzing cardiac function and mor-phology.We hope to use CMR to assess EAT as a bioimaging marker to evaluate HFpEF in obese patients.AIM To assess the diagnostic utility of CMR for evaluating heart failure with preserved ejection fraction[HFpEF;left ventricular(LV)ejection fraction≥50%]by measuring the epicardial adipose tissue(EAT)volumes and EAT mass in obese patients.METHODS Sixty-two obese patients were divided into two groups for a case-control study based on whether or not they had heart failure with HFpEF.The two groups were defined as HFpEF+and HFpEF-.LV geometry,global systolic function,EAT volumes and EAT mass of all subjects were obtained using cine magnetic resonance sequences.RESULTS Forty-five patients of HFpEF-group and seventeen patients of HFpEF+group were included.LV mass index(g/m2)of HFpEF+group was higher than HFpEF-group(P<0.05).In HFpEF+group,EAT volumes,EAT volume index,EAT mass,EAT mass index and the ratio of EAT/[left atrial(LA)left-right(LR)diameter]were higher compared to HFpEF-group(P<0.05).In multivariate analysis,Higher EAT/LA LR diameter ratio was associated with higher odds ratio of HFpEF.CONCLUSION EAT/LA LR diameter ratio is highly associated with HFpEF in obese patients.It is plausible that there may be utility in CMR for assessing obese patients for HFpEF using EAT/LA LR diameter ratio as a diagnostic biomarker.Further prospective studies,are needed to validate these proof-of-concept findings.展开更多
A scar is a condition characterized by excessive repair of skin tissue,resulting in a fibroproliferative disorder marked by abnormal deposition of extracellular matrix.This disorder typically stems from deep dermal da...A scar is a condition characterized by excessive repair of skin tissue,resulting in a fibroproliferative disorder marked by abnormal deposition of extracellular matrix.This disorder typically stems from deep dermal damage caused by burns or trauma and presents with symptoms such as itching and pain.Moreover,scarring can lead to disfigurement and psychological distress in affected individuals,making it a prevalent concern in burn plastic surgery outpatient clinics.In the current scar treatment landscape,one of the forefront approaches involves the grafting of adipose tissue and its components.This cutting-edge methodology encompasses various techniques,including nanofat grafting,adipose-derived stem cell matrigel applications,stromal vascular component transplantation,and adipose-derived mesenchymal stem cell infusion.Research in this domain has consistently demonstrated the remarkable capabilities of adipose tissue and its components in tissue regeneration,extracellular matrix remodeling,and anti-fibrotic actions.Notably,topical grafting of adipose tissue has emerged as a promising therapeutic avenue,showing significant improvements in both visual appearance and symptomatic relief associated with scars.The multifaceted functions of adipose tissue play a pivotal role in enhancing the overall outcomes of scar treatments.Therefore,this review aims to comprehensively evaluate and highlight the role of adipose tissue and its various components in scar treatment.By providing a theoretical foundation,this review aimed to serve as a valuable reference for improving the efficacy of scar management strategies.展开更多
During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).Based on the results o...During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).Based on the results of previous studies,other adipose tissue depots(e.g.,perirenal and subcutaneous)develop from the fetal stage primarily as brown adipose tissue.The hyperplastic stage of intramuscular adipose is considered to develop from late pregnancy,but there is no evidence indicating that intramuscular adipose tissue develops initially as brown adipose tissue.Hyperplastic growth of intramuscular adipose continues well into postweaning and is dependent on the timing of the transition to grain-based diets;thereafter,the late-stage development of intramuscular adipose tissue is dominated by hypertrophy.For muscle development,hyperplasia of myoblasts lasts from early(following development of somites in the embryo)to middle pregnancy,after which growth of muscle is the result of hypertrophy of myofibers.Vitamin A is a fat-soluble compound that is required for the normal immunologic function,vision,cellular proliferation,and differentiation.Here we review the roles of vitamin A in intramuscular adipose tissue and muscle development in cattle.Vitamin A regulates both hyperplasia and hypertrophy in in vitro experiments.Vitamin A supplementation at the early stage and restriction at fattening stage generate opposite effects in the beef cattle.Appropriate vitamin A supplementation and restriction strategy increase intramuscular adipose tissue development(i.e.,marbling or intramuscular fat)in some in vivo trials.Besides,hyperplasia and hypertrophy of myoblasts/myotubes were affected by vitamin A treatment in in vitro trials.Additionally,some studies reported an interaction between the alcohol dehydrogenase-1C(ADH1C)genotype and vitamin A feed restriction for the development of marbling and/or intramuscular adipose tissue,which was dependent on the timing and level of vitamin A restriction.Therefore,the feed strategy of vitamin A has the visible impact on the marbling and muscle development in the cattle,which will be helpful to promote the quality of the beef.展开更多
Type-2 diabetes mellitus(T2DM) plays a central role in the development of cardiovascular disease(CVD). However, its relationship to epicardial adipose tissue(EAT) and pericardial adipose tissue(PAT) in particular is i...Type-2 diabetes mellitus(T2DM) plays a central role in the development of cardiovascular disease(CVD). However, its relationship to epicardial adipose tissue(EAT) and pericardial adipose tissue(PAT) in particular is important in the pathophysiology of coronary artery disease. Owing to its close proximity to the heart and coronary vasculature, EAT exerts a direct metabolic impact by secreting proinflammatory adipokines and free fatty acids, which promote CVD locally. In this review, we have discussed the relationship between T2 DM and cardiac fat deposits, particularly EAT and PAT, which together exert a big impact on the cardiovascular health.展开更多
Ectopic adiposity has gained considerable attention because of its tight association with metabolic and cardiovascular health in persons with spinal cord injury(SCI). Ectopic adiposity is characterized by the storag...Ectopic adiposity has gained considerable attention because of its tight association with metabolic and cardiovascular health in persons with spinal cord injury(SCI). Ectopic adiposity is characterized by the storage of adipose tissue in non-subcutaneous sites. Magnetic resonance imaging(MRI) has proven to be an effective tool in quantifying ectopic adiposity and provides the opportunity to measure different adipose depots including intermuscular adipose tissue(IMAT) and intramuscular adipose tissue(Intra MAT) or intramuscular fat(IMF). It is highly important to distinguish and clearly define these compartments, because controversy still exists on how to accurately quantify these adipose depots. Investigators have relied on separating muscle from fat pixels based on their characteristic signal intensities. A common technique is plotting a threshold histogram that clearly separates between muscle and fat peaks. The cut-offs to separate between muscle and fat peaks are still not clearly defined and different cut-offs have been identified. This review will outline and compare the Midpoint and Otsu techniques, two methods used to determine the threshold between muscle and fat pixels on T1 weighted MRI. The process of water/fat segmentation using the Dixon method will also be outlined. We are hopeful that this review will trigger more research towards accurately quantifying ectopic adiposity due to its high relevance to cardiometabolic health after SCI.展开更多
Visceral and subcutaneous are the two major types of bovine adipose tissues, and they show metabolic and functional differences according to their distribution, exploring the transcriptional features of visceral and s...Visceral and subcutaneous are the two major types of bovine adipose tissues, and they show metabolic and functional differences according to their distribution, exploring the transcriptional features of visceral and subcutaneous adipose tissues is necessary. In the present study, we conducted RNA-seq analysis to compare the transcriptome between visceral (great omental) and subcutaneous (backfat) adipose tissues from Chinese Simmental cattle and validate them by qRT-PCR. We found that 5864 genes were differentially expressed between two tissues, including 2979 up-regulated and 2885 down-regulated in visceral adipose tissue. Functional analysis revealed a variety of differentially expressed genes (DEGs) involved in lipid metabolism and immune response processes. This may provide valuable information to further our understanding of the complexity of gene regulation governing the physiology of different fat depots. This work highlighted potential genes regulating lipid metabolism and immune responses;it may contribute to a better understanding of the metabolic and functional differences between visceral and subcutaneous adipose tissues.展开更多
Nonalcoholic fatty liver disease (NAFLD) is an increasingly recognized cause of liver-related morbidity and mortality. It can develop secondary to numerous causes but a great majority of NAFLD cases occur in patient...Nonalcoholic fatty liver disease (NAFLD) is an increasingly recognized cause of liver-related morbidity and mortality. It can develop secondary to numerous causes but a great majority of NAFLD cases occur in patients who are obese or present with other components of metabolic syndrome (hypertension, dyslipidemia, diabetes). This is called primary NAFLD and insulin resistance plays a key role in its pathogenesis. Obesity is characterized by expanded adipose tissue, which is under a state of chronic inflammation. This disturbs the normal storage and endocrine functions of adipose tissue. In obesity, the secretome (adipokines, oytokines, free fatty acids and other lipid moieties) of fatty tissue is amplified, which through its autocrine, paracrine actions in fat tissue and systemic effects especially in the liver leads to an altered metabolic state with insulin resistance (IR). IR leads to hyperglycemia and reactive hyperinsulinemia, which stimulates lipid-accumulating processes and impairs hepatic lipid metabolism. IR enhances free fatty acid delivery to liver from the adipose tissue storage due to uninhibited lipolysis. These changes result in hepatic abnormal fat accumulation, which may initiate the hepatic IR and further aggravate the altered metabolic state of whole body. Hepatic steatosis can also be explained by the fact that there is enhanced dietary fat delivery and physical inactivity. IR and NAFLD are also seen in various lipodystrophic states in contrary to popular belief that these problems only occur due to excessive adiposity in obesity. Hence, altered physiology of adipose tissue is central to development of IR, metabolic syndrome and NAFLD.展开更多
AIM: To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells (ADSC) and bone marrow-derived mesenchymal stem cells (BMSC) in vitro. Transdifferentiation of BMSC into h...AIM: To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells (ADSC) and bone marrow-derived mesenchymal stem cells (BMSC) in vitro. Transdifferentiation of BMSC into hepatic cells in vivo has been described. Adipose tissue represents an accessible source of ADSC, with similar characteristics to BMSC. METHODS: BMSCs were obtained from patients undergoing total hip arthroplasty and ADSC from human adipose tissue obtained from lipectomy. Cells were grown in medium containing 15% human serum. Cultures were serum deprived for 2 d before cultivating under similar pro-hepatogenic conditions to those of liver development using a 2-step protocol with sequential addition of growth factors, cytokines and hormones. Hepatic differentiation was RT-PCR-assessed and liver-marker genes were immunohistochemically analysed.RESULTS: BMSC and ADSC exhibited a fibroblastic morphology that changed to a polygonal shape when cells differentiated. Expression of stem cell marker Thyl decreased in differentiated ADSC and BMSC. However, the expression of the hepatic markers, albumin and CYPs increased to a similar extent in differentiated BMSC and ADSC. Hepatic gene activation could be attributed to increased liver-enriched transcription factors (C/EBPβ and HNF4α), as demonstrated by adenoviral expression vectors.CONCLUSION: Mesenchymal stem cells can be induced to hepatogenic transdifferentiation in vitro. ADSCs have a similar hepatogenic differentiation potential to BMSC, but a longer culture period and higher proliferation capacity. Therefore, adipose tissue may be an ideal source of large amounts of autologous stem cells, and may become an alternative for hepatocyte regeneration, liver cell transplantation or preclinical drug testing.展开更多
BACKGROUND: Acute rejection after liver transplantation is usually treated with large doses of immunosuppressants with severe toxic and side-effects, so it is imperative to find a safe and effective method for prevent...BACKGROUND: Acute rejection after liver transplantation is usually treated with large doses of immunosuppressants with severe toxic and side-effects, so it is imperative to find a safe and effective method for preventing and treating rejection. This study was designed to confirm the immunomodulatory effects of rat mesenchymal stem cells (MSCs) in vitro and investigate the tolerogenic features in a rat model of allogeneic liver transplantation. METHODS: MSCs were isolated from adipose tissue of Sprague-Dawley (SD) rats and cultured. In vitro, MSCs were added into a mixed lymphocyte culture (MLC) system to study the inhibitory effects of MSCs on the proliferation of T lymphocytes in Wistar rats. By using SD and Wistar rats as liver donors and recipients, an orthotopic liver transplantation model was established and the rats were divided into a MSC-treated group and a blank control group. On postoperative day 7, all rats were sacrificed, and the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), interleukin-2 (IL-2) and interleukin-10 (IL-10) were measured. The pathological changes of liver tissue and apoptosis of hepatocytes were also assessed. RESULTS: In in vitro MLC, T lymphocyte proliferation in Wistar rats was significantly inhibited by 48.44%. In the MSC-treated group, the levels of ALT, AST, TBIL, IL-2 and IL-10 were 134.2 +/- 45.0 U/L, 162.5 +/- 30.5 U/L, 30.6 +/- 5.4 mu mol/L, 187.35 +/- 18.26 mu g/L and 193.95 +/- 37.62 mu g/L, and those in the blank control group were 355.6 +/- 54.3 U/L, 296.4 +/- 71.2 U/L, 145.7 +/- 28.6 +/- mol/L, 295.73 +/- 57.15 mu g/L and 75.12 +/- 11.23 mu g/L, respectively, with statistically significant differences (P<0.05). Pathological examination revealed that the rejection in the MSC-treated group was clearly alleviated compared with that in the blank control group. TUNEL indicated that the apoptosis of hepatocytes in the MSC-treated group was milder than that in the blank control group (P<0.05). CONCLUSION: Adipose-derived MSCs clearly inhibit recipient-derived T lymphocyte proliferation in MLC and significantly alleviate acute rejection following orthotopic liver transplantation in rats.展开更多
When adipose-derived stem cells (ASCs) arc retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based...When adipose-derived stem cells (ASCs) arc retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based on their buoyancy, mature adipocytes can be easily isolated from the adipose cell suspension and dediffercn- tiated into lipid-frce fibroblast-like cells, named dediffercntiated fat (DFAT) cells. DFAT cells rc-establish active proliferation ability and undertake multipotent capacities. Compared with ASCs and other adult stem cells, DFAT cells showed unique advantages in their abundance, isolation and homogeneity. In this concise review, the establishment and culture methods of DFAT cells arc introduced and the current profiles of their cellular nature are summarized. Under proper inducti~,n culture in vitro or environment in vivo, DFAT cells could demonstrate adipogenic, osteogenic, chondrogenie and myogenic potentials. In angiogenie conditions, DFAT cells could exhibit perivascular characteristics antt elicit neovascularization. Our preliminary findings also suggested the pericyte phenotype underlying such cell lineage, which supported a novel interpretation about the common origin of mesenchymal stem cells and tissue-specific stem cells within blood vessel walls. Current research on DFAT cells indicated that this alternative source of adult multipotent cells has great potential in tissue engineering and regenerative medicine.展开更多
Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease worldwide.Its pathogenesis is complex and not yet fully understood.Over the years many studies have proposed various pathophysiological ...Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease worldwide.Its pathogenesis is complex and not yet fully understood.Over the years many studies have proposed various pathophysiological hypotheses,among which the currently most widely accepted is the"multiple parallel hits"theory.According to this model,lipid accumulation in the hepatocytes and insulin resistance increase the vulnerability of the liver to many factors that act in a coordinated and cooperative manner to promote hepatic injury,inflammation and fibrosis.Among these factors,adipose tissue dysfunction and subsequent chronic low grade inflammation play a crucial role.Recent studies have shown that vitamin D exerts an immune-regulating action on adipose tissue,and the growing wealth of epidemiological data is demonstrating that hypovitaminosis D is associated with both obesity and NAFLD.Furthermore,given the strong association between these conditions,current findings suggest that vitamin D may be involved in the relationship between adipose tissue dysfunction and NAFLD.The purpose of this review is to provide an overview of recent advances in the pathogenesis of NAFLD in relation to adipose tissue dysfunction,and in the pathophysiology linking vitamin D deficiency with NAFLD and adiposity,together with an overview of the evidence available on the clinical utility of vitamin D supplementation in cases of NAFLD.展开更多
基金the National Natural Science Foundation of China(grant no.82272289).
文摘Aging is one of the most significant health challenges worldwide and is a primary cause of chronic diseases and physiological decline.Among the myriad changes that occur with aging,alterations in adipose tissue distribution and function have gained considerable attention because of their profound impact on metabolic health and overall well-being.Subcutaneous adipose tissue(SAT)and visceral adipose tissue(VAT)are the two major depots of white adipose tissue,each with distinct roles in metabolism and health.Understanding the characteristics and underlying mechanisms of SAT and VAT is crucial for elucidating the aging process and developing strategies to promote healthy aging.This review focuses on delineating and analyzing the characteristics and intrinsic mechanisms underlying the aging of subcutaneous and visceral adipose tissue during the aging process,which can contribute to a better understanding of the aging process and enhance healthy aging.
基金Supported by American College of Gastroenterology,Clinical Research Award 2022,No.ACG-CR-040-2022National Institute of Diabetes and Digestive and Kidney Diseases,U01,No.2299170Helmsley Charitable Trust,No.2352240。
文摘BACKGROUND Evidence suggests inflammatory mesenteric fat is involved in post-operative recurrence(POR)of Crohn’s disease(CD).However,its prognostic value is INTRODUCTION Crohn’s disease(CD)is a debilitating chronic immune-mediated inflammatory disease(IMID)of the gastrointestinal tract that is increasing in incidence and prevalence globally[1].CD patients often undergo surgery for disease-related complic-ations and/or medically refractory disease.Unfortunately,surgery is not curative,and many patients develop post-operative recurrence(POR)of CD with a significant proportion eventually requiring additional surgeries.With advances in early detection and therapeutics,the contemporary 10-year risk of surgery has improved from 50%to 26%,but the risk of recurrent surgery has remained unchanged at 30%,suggesting a need to improve post-operative management strategies[2].Presently,there are two accepted strategies to mitigate POR,but each have potential limitations.Firstly,patients start early post-operative pharmacologic prophylaxis within 4-6 wk after surgery.This strategy can potentially overtreat a subset of patient who may not develop long-term disease recurrence off therapy.Consequently,these patients are at risk of medication-related adverse events and the direct and indirect costs associated with therapy with little or no benefit[3].The second strategy is performing early colonoscopy within 6-12 months after surgery and escalating therapy based on FOOTNOTES Author contributions:Gu P is the guarantor of the article and was involved in concept and design,data collection,statistical analysis,drafting of manuscript,and final approval of manuscript;Dube S and Choi SY were involved in statistical analysis,drafting of the manuscript,and final approval of manuscript;Gellada N,Win S,Lee YJ and Yang S were involved in the data collection,drafting of the manuscript,and final approval of manuscript;Haritunians T and Li D were involved in data analysis and interpretation,drafting of manuscript and final approval of manuscript;Melmed GY,Yarur AJ,Fleshner P,Kallman C and Devkota S were involved in study concept and design,data interpretation,drafting of manuscript and final approval of manuscript;Vasiliauskas EA,Bonthala N,Syal G,Ziring D and Targan SR were involved in data interpretation,drafting of manuscript and final approval of manuscript;Rabizadeh S was involved in study concept and design,drafting of manuscript and final approval of manuscript;McGovern DPB was involved in concept and design,statistical analysis,drafting of manuscript and final approval of manuscript.
文摘Acute pancreatitis is a common systemic inflammatory disease, manifested by a spectrum of severity, ranging from mild in the majority of patients to severe acute pancreatitis. Patients with severe acute pancreatitis suffer from severe local and systemic complications and organ failure, leading to a poor prognosis. The early recognition of the severe condition is important to improve prognosis. Obesity has risen in tandem with an increase in the severity of acute pancreatitis in recent years. Studies have revealed that adipose tissue, particularly visceral adipose tissue is associated with the prognosis of acute pancreatitis. This review discussed the role of visceral adipose tissue in obese patients with acute pancreatitis and explored the possible mechanism involved.
基金This work was financially supported by The National Key Research and Development Program of China(No.2022YFD1300202)The National Natural Science Foundation of China(No.32372834)+2 种基金Chongqing Modern Agricultural Industry Technology System(CQMAITS202313)the Collection,Utilization and Innovation of Germplasm Resources by Research Institutes and Enterprises of Chongqing,China(cqnyncw-kqlhtxm)the Chongqing Postgraduate Research Innovation Project(CYB22141).
文摘Background Brown adipose tissue(BAT)is known to be capable of non-shivering thermogenesis under cold stimulation,which is related to the mortality of animals.In the previous study,we observed that goat BAT is mainly located around the kidney at birth,and changes to white adipose tissue(WAT)in the perirenal adipose tissue of goats within one month after birth.However,the regulatory factors underlying this change is remain unclear.In this study,we systematically studied the perirenal adipose tissue of goat kids in histological,cytological,and accompanying molecular level changes from 0 to 28 d after birth.Results Our study found a higher mortality rate in winter-born goat kids,with goat birthing data statistics.Then we used thermal imaging revealing high temperature in goat hips at postnatal 0 d and gradually decrease during 28 d.This is consistent with the region of perirenal BAT deposition and highlights its critical role in energy expenditure and body temperature regulation in goat kids.Additionally,we found a series of changes of BAT during the first 28 d after birth,such as whitening,larger lipid droplets,decreased mitochondrial numbers,and down-regulation of key thermogenesis-related genes(UCP1,DIO2,UCP2,CIDEA,PPARGC1a,C/EBPb,and C/EBPa).Then,we used RNA-seq found specific marker genes for goat adipose tissue and identified 12 new marker genes for BAT and 10 new marker genes for WAT of goats.Furthermore,12 candidate genes were found to potentially regulate goat BAT thermogenesis.The mechanism of the change of this biological phenomenon does not involve a large-scale death of brown adipocytes and subsequent proliferation of white adipocytes.While apoptosis may play a limited role,it is largely not critical in this transition process.Conclusions We concluded that perirenal BAT plays a crucial role in thermoregulation in newborn goat kids,with notable species differences in the expression of adipose tissue marker genes,and we highlighted some potential marker genes for goat BAT and WAT.Additionally,the change from BAT to WAT does not involve a large-scale death of brown adipocytes and subsequent proliferation of white adipocytes.
基金supported by the National Natural Science Foundation of China(No.82070859).
文摘Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body metabolism.Exosomes are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(AT Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine mechanisms.However,the roles of AT Exos in crosstalk with metabolic organs remain to be fully elucidated.In this review,we summarize the latest research progress on the role of AT Exos in the regulation of metabolic disorders.Moreover,we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.
基金This study was supported by a grant from Beijing Natural Science Foundation(7234399).
文摘Background:Visceral adipose tissue(VAT)has been linked to the severe acute pancreatitis(SAP)prognosis,although the underlying mechanism remains unclear.It has been reported that pyroptosis worsens SAP.The present study aimed to verify whether mesenteric adipose tissue(MAT,a component of VAT)can cause secondary intestinal injury through the pyroptotic pathway.Methods:Thirty-six male Sprague Dawley(SD)rats were divided into six different groups.Twelve rats were randomly divided into the SAP and control groups.We monitored the changes of MAT and B lymphocytes infiltration in MAT of SAP rats.Twelve SAP rats were injected with MAT B lymphocytes or phosphate buffer solution(PBS).The remaining twelve SAP rats were first injected with MAT B lymphocytes,and then with MCC950(NLRP3 inhibitor)or PBS.We collected blood and tissue samples from pancreas,gut and MAT for analysis.Results:Compared to the control rats,the SAP group showed inflammation in MAT,including higher expression of tumor necrosis factor(TNF-α)and interleukin-6(IL-6),lower expression of IL-10,and histological changes.Flow cytometry analysis revealed B lymphocytes infiltration in MAT but not T lymphocytes and macrophages.The SAP rats also exhibited intestinal injury,characterized by lower expression of zonula occludens-1(ZO-1)and occludin,higher levels of lipopolysaccharide and diamine oxidase,and pathological changes.The expression of NLRP3 and n-GSDMD,which are responsible for pyroptosis,was increased in the intestine of SAP rats.The injection of MAT B lymphocytes into SAP rats exacerbated the inflammation in MAT.The upregulation of pyroptosis reduced tight junction in the intestine,which contributed to the SAP progression,including higher inflammatory indicators and worse histological changes.The administration of MCC950 to SAP+MAT B rats downregulated pyroptosis,which subsequently improved the intestinal barrier and ameliorated inflammatory response of SAP.Conclusions:In SAP,MAT B lymphocytes aggravated local inflammation,and promoted the injury to the intestine through the enteric pyroptotic pathway.
基金supported by USDA-National Institute of Food and Agriculture (Washington, DC) competitive grants 2019-67015-29443 and 202167015-34563Department of Large Animal Clinical Sciences (East Lansing, MI), Office of the Associate Dean for Research and Graduate Studies of the College of Veterinary Medicine (East Lansing, MI)+2 种基金Michigan State University College of Veterinary Medicine Endowed Research Funds 2020 (East Lansing, MIRobert and Janet Hafner Fund for Animal Health)the Michigan Alliance for Animal Agriculture (East Lansing, awards AA-21-154, AA-22-055)。
文摘During the periparturient period, dairy cows exhibit negative energy balance due to limited appetite and increased energy requirements for lactogenesis. The delicate equilibrium between energy availability and expenditure puts cows in a state of metabolic stress characterized by excessive lipolysis in white adipose tissues(AT), increased production of reactive oxygen species, and immune cell dysfunction. Metabolic stress, especially in AT, increases the risk for metabolic and inflammatory diseases. Around parturition, cows are also susceptible to endotoxemia. Bacterial-derived toxins cause endotoxemia by promoting inflammatory processes and immune cell infiltration in different organs and systems while impacting metabolic function by altering lipolysis, mitochondrial activity, and insulin sensitivity. In dairy cows, endotoxins enter the bloodstream after overcoming the defense mechanisms of the epithelial barriers, particularly during common periparturient conditions such as mastitis, metritis, and pneumonia, or after abrupt changes in the gut microbiome. In the bovine AT, endotoxins induce a pro-inflammatory response and stimulate lipolysis in AT, leading to the release of free fatty acids into the bloodstream. When excessive and protracted, endotoxin-induced lipolysis can impair adipocyte's insulin signaling pathways and lipid synthesis. Endotoxin exposure can also induce oxidative stress in AT through the production of reactive oxygen species by inflammatory cells and other cellular components. This review provides insights into endotoxins' impact on AT function, highlighting the gaps in our knowledge of the mechanisms underlying AT dysfunction, its connection with periparturient cows' disease risk, and the need to develop effective interventions to prevent and treat endotoxemia-related inflammatory conditions in dairy cattle.
文摘In this letter,we commented on the article by Wu et al.We examined the interactions between mesenteric adipose tissue,creeping fat,and gut microbiota in Crohn’s disease(CD),a condition marked by chronic gastrointestinal inflammation with a rising global incidence.The pathogenesis of CD involves complex genetic,environmental,and microbial factors.Dysbiosis,which is an imbalance in gut microbial communities,is frequently observed in CD patients,highlighting the pivotal role of the gut microbiota in disease progression and the inflammatory response.Recent studies have shown that mesenteric adipose tissue and creeping fat actively contribute to inflammation by producing proinflammatory cytokines.The relationship between creeping fat and altered microbiota can shift from a potentially protective role to one that encourages bacterial translocation,further complicating disease management.Recent research has suggested that fecal microbiota transplantation could help restore microbial balance,offering a promising therapeutic strategy to improve clinical disease response.
基金Supported by National Natural Science Foundation of China(General Program),No.82070852 and No.82270901.
文摘BACKGROUND The mechanism of improvement of type 2 diabetes after duodenal-jejunal bypass(DJB)surgery is not clear.AIM To study the morphological and functional changes in adipose tissue after DJB and explore the potential mechanisms contributing to postoperative insulin sensitivity improvement of adipose tissue in a diabetic male rat model.METHODS DJB and sham surgery was performed in a-high-fat-diet/streptozotocin-induced diabetic rat model.All adipose tissue was weighed and observed under microscope.Use inguinal fat to represent subcutaneous adipose tissue(SAT)and mesangial fat to represent visceral adipose tissue.RNA-sequencing was utilized to evaluate gene expression alterations adipocytes.The hematoxylin and eosin staining,reverse transcription-quantitative polymerase chain reaction,western blot,and enzyme-linked immunosorbent assay were used to study the changes.Insulin resistance was evaluated by immunofluorescence.RESULTS After DJB,whole body blood glucose metabolism and insulin sensitivity in adipose tissue improved.Fat cell volume in both visceral adipose tissue(VAT)and SAT increased.Compared to SAT,VAT showed more significantly functional alterations after DJB and KEGG analysis indicated growth hormone(GH)pathway and downstream adiponectin secretion were involved in metabolic regulation.The circulating GH and adiponectin levels and GH receptor and adiponectin levels in VAT increased.Cytological experiment showed that GH stimulated adiponectin secretion and improve insulin sensitivity.CONCLUSION GH improves insulin resistance in VAT in male diabetic rats after receiving DJB,possibly by increasing adiponectin secretion.
基金National Natural Science Foundation of China,No.81873887National Natural Science Foundation of China Youth Project,No.82101981Shanghai Jiao Tong University School of Medicine Double Hundred Outstanding Person Project,No.20191904。
文摘BACKGROUND Obesity has become a serious public health issue,significantly elevating the risk of various complications.It is a well-established contributor to Heart failure with preserved ejection fraction(HFpEF).Evaluating HFpEF in obesity is crucial.Epicardial adipose tissue(EAT)has emerged as a valuable tool for validating prognostic biomarkers and guiding treatment targets.Hence,assessing EAT is of paramount importance.Cardiovascular magnetic resonance(CMR)imaging is acknowledged as the gold standard for analyzing cardiac function and mor-phology.We hope to use CMR to assess EAT as a bioimaging marker to evaluate HFpEF in obese patients.AIM To assess the diagnostic utility of CMR for evaluating heart failure with preserved ejection fraction[HFpEF;left ventricular(LV)ejection fraction≥50%]by measuring the epicardial adipose tissue(EAT)volumes and EAT mass in obese patients.METHODS Sixty-two obese patients were divided into two groups for a case-control study based on whether or not they had heart failure with HFpEF.The two groups were defined as HFpEF+and HFpEF-.LV geometry,global systolic function,EAT volumes and EAT mass of all subjects were obtained using cine magnetic resonance sequences.RESULTS Forty-five patients of HFpEF-group and seventeen patients of HFpEF+group were included.LV mass index(g/m2)of HFpEF+group was higher than HFpEF-group(P<0.05).In HFpEF+group,EAT volumes,EAT volume index,EAT mass,EAT mass index and the ratio of EAT/[left atrial(LA)left-right(LR)diameter]were higher compared to HFpEF-group(P<0.05).In multivariate analysis,Higher EAT/LA LR diameter ratio was associated with higher odds ratio of HFpEF.CONCLUSION EAT/LA LR diameter ratio is highly associated with HFpEF in obese patients.It is plausible that there may be utility in CMR for assessing obese patients for HFpEF using EAT/LA LR diameter ratio as a diagnostic biomarker.Further prospective studies,are needed to validate these proof-of-concept findings.
基金supported by the Bashkir State Medical University Strategic Academic Leadership Program(grant no.PRIORITY-2030).
文摘A scar is a condition characterized by excessive repair of skin tissue,resulting in a fibroproliferative disorder marked by abnormal deposition of extracellular matrix.This disorder typically stems from deep dermal damage caused by burns or trauma and presents with symptoms such as itching and pain.Moreover,scarring can lead to disfigurement and psychological distress in affected individuals,making it a prevalent concern in burn plastic surgery outpatient clinics.In the current scar treatment landscape,one of the forefront approaches involves the grafting of adipose tissue and its components.This cutting-edge methodology encompasses various techniques,including nanofat grafting,adipose-derived stem cell matrigel applications,stromal vascular component transplantation,and adipose-derived mesenchymal stem cell infusion.Research in this domain has consistently demonstrated the remarkable capabilities of adipose tissue and its components in tissue regeneration,extracellular matrix remodeling,and anti-fibrotic actions.Notably,topical grafting of adipose tissue has emerged as a promising therapeutic avenue,showing significant improvements in both visual appearance and symptomatic relief associated with scars.The multifaceted functions of adipose tissue play a pivotal role in enhancing the overall outcomes of scar treatments.Therefore,this review aims to comprehensively evaluate and highlight the role of adipose tissue and its various components in scar treatment.By providing a theoretical foundation,this review aimed to serve as a valuable reference for improving the efficacy of scar management strategies.
基金This work was supported by a Cooperation Research Project(2020R1A2B5B02001843)funded by the National Research Foundation of Korea.
文摘During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).Based on the results of previous studies,other adipose tissue depots(e.g.,perirenal and subcutaneous)develop from the fetal stage primarily as brown adipose tissue.The hyperplastic stage of intramuscular adipose is considered to develop from late pregnancy,but there is no evidence indicating that intramuscular adipose tissue develops initially as brown adipose tissue.Hyperplastic growth of intramuscular adipose continues well into postweaning and is dependent on the timing of the transition to grain-based diets;thereafter,the late-stage development of intramuscular adipose tissue is dominated by hypertrophy.For muscle development,hyperplasia of myoblasts lasts from early(following development of somites in the embryo)to middle pregnancy,after which growth of muscle is the result of hypertrophy of myofibers.Vitamin A is a fat-soluble compound that is required for the normal immunologic function,vision,cellular proliferation,and differentiation.Here we review the roles of vitamin A in intramuscular adipose tissue and muscle development in cattle.Vitamin A regulates both hyperplasia and hypertrophy in in vitro experiments.Vitamin A supplementation at the early stage and restriction at fattening stage generate opposite effects in the beef cattle.Appropriate vitamin A supplementation and restriction strategy increase intramuscular adipose tissue development(i.e.,marbling or intramuscular fat)in some in vivo trials.Besides,hyperplasia and hypertrophy of myoblasts/myotubes were affected by vitamin A treatment in in vitro trials.Additionally,some studies reported an interaction between the alcohol dehydrogenase-1C(ADH1C)genotype and vitamin A feed restriction for the development of marbling and/or intramuscular adipose tissue,which was dependent on the timing and level of vitamin A restriction.Therefore,the feed strategy of vitamin A has the visible impact on the marbling and muscle development in the cattle,which will be helpful to promote the quality of the beef.
文摘Type-2 diabetes mellitus(T2DM) plays a central role in the development of cardiovascular disease(CVD). However, its relationship to epicardial adipose tissue(EAT) and pericardial adipose tissue(PAT) in particular is important in the pathophysiology of coronary artery disease. Owing to its close proximity to the heart and coronary vasculature, EAT exerts a direct metabolic impact by secreting proinflammatory adipokines and free fatty acids, which promote CVD locally. In this review, we have discussed the relationship between T2 DM and cardiac fat deposits, particularly EAT and PAT, which together exert a big impact on the cardiovascular health.
基金supported in part by Grant-in-Aid for JSPS Research Fellow
文摘Ectopic adiposity has gained considerable attention because of its tight association with metabolic and cardiovascular health in persons with spinal cord injury(SCI). Ectopic adiposity is characterized by the storage of adipose tissue in non-subcutaneous sites. Magnetic resonance imaging(MRI) has proven to be an effective tool in quantifying ectopic adiposity and provides the opportunity to measure different adipose depots including intermuscular adipose tissue(IMAT) and intramuscular adipose tissue(Intra MAT) or intramuscular fat(IMF). It is highly important to distinguish and clearly define these compartments, because controversy still exists on how to accurately quantify these adipose depots. Investigators have relied on separating muscle from fat pixels based on their characteristic signal intensities. A common technique is plotting a threshold histogram that clearly separates between muscle and fat peaks. The cut-offs to separate between muscle and fat peaks are still not clearly defined and different cut-offs have been identified. This review will outline and compare the Midpoint and Otsu techniques, two methods used to determine the threshold between muscle and fat pixels on T1 weighted MRI. The process of water/fat segmentation using the Dixon method will also be outlined. We are hopeful that this review will trigger more research towards accurately quantifying ectopic adiposity due to its high relevance to cardiometabolic health after SCI.
文摘Visceral and subcutaneous are the two major types of bovine adipose tissues, and they show metabolic and functional differences according to their distribution, exploring the transcriptional features of visceral and subcutaneous adipose tissues is necessary. In the present study, we conducted RNA-seq analysis to compare the transcriptome between visceral (great omental) and subcutaneous (backfat) adipose tissues from Chinese Simmental cattle and validate them by qRT-PCR. We found that 5864 genes were differentially expressed between two tissues, including 2979 up-regulated and 2885 down-regulated in visceral adipose tissue. Functional analysis revealed a variety of differentially expressed genes (DEGs) involved in lipid metabolism and immune response processes. This may provide valuable information to further our understanding of the complexity of gene regulation governing the physiology of different fat depots. This work highlighted potential genes regulating lipid metabolism and immune responses;it may contribute to a better understanding of the metabolic and functional differences between visceral and subcutaneous adipose tissues.
文摘Nonalcoholic fatty liver disease (NAFLD) is an increasingly recognized cause of liver-related morbidity and mortality. It can develop secondary to numerous causes but a great majority of NAFLD cases occur in patients who are obese or present with other components of metabolic syndrome (hypertension, dyslipidemia, diabetes). This is called primary NAFLD and insulin resistance plays a key role in its pathogenesis. Obesity is characterized by expanded adipose tissue, which is under a state of chronic inflammation. This disturbs the normal storage and endocrine functions of adipose tissue. In obesity, the secretome (adipokines, oytokines, free fatty acids and other lipid moieties) of fatty tissue is amplified, which through its autocrine, paracrine actions in fat tissue and systemic effects especially in the liver leads to an altered metabolic state with insulin resistance (IR). IR leads to hyperglycemia and reactive hyperinsulinemia, which stimulates lipid-accumulating processes and impairs hepatic lipid metabolism. IR enhances free fatty acid delivery to liver from the adipose tissue storage due to uninhibited lipolysis. These changes result in hepatic abnormal fat accumulation, which may initiate the hepatic IR and further aggravate the altered metabolic state of whole body. Hepatic steatosis can also be explained by the fact that there is enhanced dietary fat delivery and physical inactivity. IR and NAFLD are also seen in various lipodystrophic states in contrary to popular belief that these problems only occur due to excessive adiposity in obesity. Hence, altered physiology of adipose tissue is central to development of IR, metabolic syndrome and NAFLD.
基金Supported by the ALIVE Foundation, the FIS from Instituto de Salud Carlos III, Spain, No. 03/0339, and the European Commission, No. LSHB-CT-2004-504761
文摘AIM: To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells (ADSC) and bone marrow-derived mesenchymal stem cells (BMSC) in vitro. Transdifferentiation of BMSC into hepatic cells in vivo has been described. Adipose tissue represents an accessible source of ADSC, with similar characteristics to BMSC. METHODS: BMSCs were obtained from patients undergoing total hip arthroplasty and ADSC from human adipose tissue obtained from lipectomy. Cells were grown in medium containing 15% human serum. Cultures were serum deprived for 2 d before cultivating under similar pro-hepatogenic conditions to those of liver development using a 2-step protocol with sequential addition of growth factors, cytokines and hormones. Hepatic differentiation was RT-PCR-assessed and liver-marker genes were immunohistochemically analysed.RESULTS: BMSC and ADSC exhibited a fibroblastic morphology that changed to a polygonal shape when cells differentiated. Expression of stem cell marker Thyl decreased in differentiated ADSC and BMSC. However, the expression of the hepatic markers, albumin and CYPs increased to a similar extent in differentiated BMSC and ADSC. Hepatic gene activation could be attributed to increased liver-enriched transcription factors (C/EBPβ and HNF4α), as demonstrated by adenoviral expression vectors.CONCLUSION: Mesenchymal stem cells can be induced to hepatogenic transdifferentiation in vitro. ADSCs have a similar hepatogenic differentiation potential to BMSC, but a longer culture period and higher proliferation capacity. Therefore, adipose tissue may be an ideal source of large amounts of autologous stem cells, and may become an alternative for hepatocyte regeneration, liver cell transplantation or preclinical drug testing.
文摘BACKGROUND: Acute rejection after liver transplantation is usually treated with large doses of immunosuppressants with severe toxic and side-effects, so it is imperative to find a safe and effective method for preventing and treating rejection. This study was designed to confirm the immunomodulatory effects of rat mesenchymal stem cells (MSCs) in vitro and investigate the tolerogenic features in a rat model of allogeneic liver transplantation. METHODS: MSCs were isolated from adipose tissue of Sprague-Dawley (SD) rats and cultured. In vitro, MSCs were added into a mixed lymphocyte culture (MLC) system to study the inhibitory effects of MSCs on the proliferation of T lymphocytes in Wistar rats. By using SD and Wistar rats as liver donors and recipients, an orthotopic liver transplantation model was established and the rats were divided into a MSC-treated group and a blank control group. On postoperative day 7, all rats were sacrificed, and the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), interleukin-2 (IL-2) and interleukin-10 (IL-10) were measured. The pathological changes of liver tissue and apoptosis of hepatocytes were also assessed. RESULTS: In in vitro MLC, T lymphocyte proliferation in Wistar rats was significantly inhibited by 48.44%. In the MSC-treated group, the levels of ALT, AST, TBIL, IL-2 and IL-10 were 134.2 +/- 45.0 U/L, 162.5 +/- 30.5 U/L, 30.6 +/- 5.4 mu mol/L, 187.35 +/- 18.26 mu g/L and 193.95 +/- 37.62 mu g/L, and those in the blank control group were 355.6 +/- 54.3 U/L, 296.4 +/- 71.2 U/L, 145.7 +/- 28.6 +/- mol/L, 295.73 +/- 57.15 mu g/L and 75.12 +/- 11.23 mu g/L, respectively, with statistically significant differences (P<0.05). Pathological examination revealed that the rejection in the MSC-treated group was clearly alleviated compared with that in the blank control group. TUNEL indicated that the apoptosis of hepatocytes in the MSC-treated group was milder than that in the blank control group (P<0.05). CONCLUSION: Adipose-derived MSCs clearly inhibit recipient-derived T lymphocyte proliferation in MLC and significantly alleviate acute rejection following orthotopic liver transplantation in rats.
文摘When adipose-derived stem cells (ASCs) arc retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based on their buoyancy, mature adipocytes can be easily isolated from the adipose cell suspension and dediffercn- tiated into lipid-frce fibroblast-like cells, named dediffercntiated fat (DFAT) cells. DFAT cells rc-establish active proliferation ability and undertake multipotent capacities. Compared with ASCs and other adult stem cells, DFAT cells showed unique advantages in their abundance, isolation and homogeneity. In this concise review, the establishment and culture methods of DFAT cells arc introduced and the current profiles of their cellular nature are summarized. Under proper inducti~,n culture in vitro or environment in vivo, DFAT cells could demonstrate adipogenic, osteogenic, chondrogenie and myogenic potentials. In angiogenie conditions, DFAT cells could exhibit perivascular characteristics antt elicit neovascularization. Our preliminary findings also suggested the pericyte phenotype underlying such cell lineage, which supported a novel interpretation about the common origin of mesenchymal stem cells and tissue-specific stem cells within blood vessel walls. Current research on DFAT cells indicated that this alternative source of adult multipotent cells has great potential in tissue engineering and regenerative medicine.
文摘Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease worldwide.Its pathogenesis is complex and not yet fully understood.Over the years many studies have proposed various pathophysiological hypotheses,among which the currently most widely accepted is the"multiple parallel hits"theory.According to this model,lipid accumulation in the hepatocytes and insulin resistance increase the vulnerability of the liver to many factors that act in a coordinated and cooperative manner to promote hepatic injury,inflammation and fibrosis.Among these factors,adipose tissue dysfunction and subsequent chronic low grade inflammation play a crucial role.Recent studies have shown that vitamin D exerts an immune-regulating action on adipose tissue,and the growing wealth of epidemiological data is demonstrating that hypovitaminosis D is associated with both obesity and NAFLD.Furthermore,given the strong association between these conditions,current findings suggest that vitamin D may be involved in the relationship between adipose tissue dysfunction and NAFLD.The purpose of this review is to provide an overview of recent advances in the pathogenesis of NAFLD in relation to adipose tissue dysfunction,and in the pathophysiology linking vitamin D deficiency with NAFLD and adiposity,together with an overview of the evidence available on the clinical utility of vitamin D supplementation in cases of NAFLD.