摘要
目的观察大剂量维生素C(VC)对外周血淋巴细胞增殖活性、抗DNA氧化损伤能力以及红细胞膜流动性的影响。方法将48只Wistar大鼠随机分为对照组、A、B、C共4组,分别给予含VC为0、2000、5000、10000mg/kg的饲料,实验期为8周。实验结束后无痛处死动物并取血,测定血浆VC、超氧化物歧化酶(SOD)和丙二醛(MDA)含量,红细胞膜谷胱甘肽过氧化物酶(GSH-Px)活性、红细胞膜流动性、淋巴细胞增殖活性,单细胞凝胶电泳计数彗星细胞测量DNA氧化损伤水平。结果与对照组比较,A组血浆SOD活性明显增高(F=2.987,q=4.24,P<0.05),血浆MDA含量明显降低(F=4.176,q=4.23,P<0.05),红细胞膜流动性和外周血淋巴细胞增殖活性均明显增高(F=2.278～2.763,q=3.67-3.84,P<0.05);C组的血浆VC含量明显升高(F=3.235,q=4.63,P<0.01),SOD和红细胞膜GSH-Px活性明显降低(F=2.987、3.478,q=3.68～4.13,P均<0.05),MDA含量明显增高(q=4.08,P<0.05)。10μmol/LH2O2诱发DNA损伤B组和C组较对照组均加重(F=4.137,q=3.94、4.25,P<0.05)。结论较高剂量VC(2000mg/kg)可明显增高大鼠机体的抗氧化损伤水平,改善红细胞膜流动性,提高淋巴细胞的增殖活性;当VC剂量超过5000mg/kg时,反而会加重淋巴细胞的DNA氧化损伤。
Objective To investigate the effects of high-dose vitamin C （VC） on peripheral blood lymphocyte （PBL） proliferation, anti-DNA oxidative damage activity and erythrocyte membrane fluidity. Methods Fifty Wistar rats were randomly di- vided into four groups： control group, and groups A, B, and C, which were fed with forage containing 0, 2 000, 5 000, and 10 000 mg/kg of VC, respectively, for eight weeks. Upon completion of the experiment, the rats were sacrificed and blood samples obtained. The levels of plasma VC, SOD, MDA and membrane GSH-Px were determined. The erythroeyte membrane fluidity was detected by fluorescence polarization method, lymphocyte transformation rate by MTT method and DNA oxidative damage by comet assay. Results Compared with the control group, plasma SOD in group A was significantly increased （F= 2. 987,q= 4.24,P〈0.05）, while MDA decreased （F：4. 176,q=4.23,P〈0.01）. The erythrocyte membrane fluidity and lymphocyte proliferation of group A were significantly increased （F：2. 278--2. 763,q=3.67--3.84,P〈0.05）. The plasma VC and MDA in group C were markedly higher than that for the control （F= 3. 235, q= 4.63, P〈0.01;q= 4.08, P〈0.05）, while SOD and GSH-Px in erythrocyte membrane in group C were significantly lower than the control （q= 3.68--4.13, P〈0.05）. The H2O2-induced DNA damages in groups B and C were more serious than that of the control （F=4. 137;q=3.94,4.25;P〈0.05）. Conclusion A higher dose （2 000 mg/kg） of VC supplementation can enhance the antioxidative activity in rats and improve erythrocyte membrane fluidity and lymphocyte proliferation. However, the oxidative damage of lymphocyte will be caused instead when the dose of VC exceeds 5 000 mg/kg.
出处
《青岛大学医学院学报》
CAS
2009年第1期21-24,共4页
Acta Academiae Medicinae Qingdao Universitatis
