摘要
目的:了解早期肠内谷氨酰胺补给对烫伤后肠黏膜屏障功能的保护作用,并探讨其可能的作用机制.方法:选取健康SD大鼠随机分为标准肠内营养组(EN组)和谷氨酰胺补给组(EN+Gln组),每组32只,制成烫伤动物模型(30%TBSAⅢ度烫伤),伤后早期分别给予标准肠内营养制剂(能全力)和标准肠内营养制剂+谷氨酰胺,于第1、4、7、10天观察血清D-乳酸,Western blo半定量分析紧密连接结构蛋白Occludin和RTPCR分析ZO-1mRNA表达的变化.结果:烫伤后血清D-乳酸水平升高,EN组在观察时间内血清D-乳酸水平没有恢复至伤前水平,EN+Gln组在伤后4d恢复(4.5±0.8mg/Lvs3.8±0.6mg/L);Western blot半定量分析显示EN+Gln组伤后Occludin表达先下降后上升在4、7d时明显高于EN组(1.18±0.14vs0.79±0.09,1.59±0.16vs1.12±0.13,均P<0.05)烧伤后1d时,2组ZO-1mRNA表达与伤前比较均明显下降(0.71±0.19,0.76±0.17vs1.00,均P<0.05),4d时EN+Gln组与EN组比较差异有显著的统计学意义(1.17±0.16vs0.76±0.15P<0.05),其余时间点各组间差异均无统计学意义.结论:早期肠内谷氨酰胺补给支持能快速逆转烧伤后TJ结构蛋白Occludin、ZO-1表达的下降,从而改善肠黏膜的屏障功能.
AIM： To investigate the protective effects of early enteral glutamine supplementation on the barrier function of intestinal mucosa in scalded rats and explore the mechanism underlying such protective effects. METHODS： Healthy adult SD rats were subjected to a 30% TBSA third-degree scald injury to develop a rat model of scald injury. Scalded rats were then randomly divided into EN and EN plus Gln group, respectively. Rats in the EN group were fed standard enteral nutrition （Nutrison Multi Fibre） while those in the EN plus Gin group were fed standard enteral nutrition plus Gln. On days 1, 4, 7 and 10 after scald induction, plasma D-lactic acid levels were analyzed by ultraviolet spectrophotometry, the expression of Occludin protein was detected by Western blot, and the expression of ZO-1 mRNA was determined by RT-PCR.RESULTS： Serum D-lactic acid level was elevated in response to scald induction. The levels of D-lactic acid in the serum of rats in the EN group did not return to normal within the period of observation of this study, whereas those in the EN plus Gln group returned to normal on day 4 after scald induction （4.5 ± 0.8 mg/L vs 3.8 ±0.6 mg/L）. Semiquantitative Western blot analysis showed that the expression of Occludin protein in intestinal mucosa of rats in the EN plus Gln group showed an initial rise, followed by a decline. On days 4 and 7, the expression level of Occludin protein in intestinal mucosa of rats in the EN plus Gin group were significantly higher than those in the EN group （1.18 ± 0.14 vs 0.79 ± 0.09 and 1.59 ± 0.16 vs 1.12 ± 0.13, respectively; both P 〈 0.05）. In both groups, the expression levels of ZO-1 mRNA on day I significantly declined when compared with pre-induction values （0.71± 0.19 and 0.76 ±0.17 vs 1.00, both P 〈 0.05）. On day 4, a significant difference was noted in the expression levels of ZO-1 mRNA between the two groups （1.17 ± 0.16 vs 0.76 ± 0.15; P 〈 0.05） though no significant differences were found at other time points. CONCLUSION： Early enteral glutamine supple-mentation is superior to standard enteral nutrition in promoting the expression of Occludin protein and ZO-1 mRNA in intestinal mucosa and improving the barrier function of intestinal mucosa.
出处
《世界华人消化杂志》
CAS
北大核心
2009年第20期2031-2036,共6页
World Chinese Journal of Digestology
基金
江西省自然科学基金项目
No.0340078~~
