波动性及恒定性高糖对牛视网膜毛细血管周细胞氧化应激的影响

目的 对比研究波动性与恒定性高糖对牛视网膜毛细血管周细胞氧化应激的影响.方法 体外培养3代融合的牛视网膜血管周细胞,分别在对照组(5.5 mmol/L)、不同浓度高糖(15 mmol/L、25 mmol/L)、不同幅度的高糖波动(5.5～15 mmol/L、5.5～25 mmol/L)下孵育6 d.硫代巴比妥酸检测培养液丙二醛(MDA)水平;黄嘌呤氧化酶法检测培养液超氧化物歧化酶(SOD)水平.结果 与对照组相比,波动性高糖组与恒定性高糖组MDA含量/SOD活力比值增加(P＜0.05),且与葡萄糖浓度及高糖波动幅度呈正相关(P＜0.01),波动性高糖1组(5.5～15 mmol/L)较恒定性高糖1组(15 mmol/L)MDA含量/SOD活性比值增加(P＜0.05),恒定性高糖2组(25 mmol/L)较波动性高糖2组(5.5～25 mmol/L)MDA含量/SOD活性比值增加(P＜0.05).结论 在一定葡萄糖浓度范围内,波动性高糖较恒定性高糖对细胞的氧化损伤加重,而超过一定葡萄糖浓度,恒定性高糖使氧化损伤更为显著.

Effects of intermittent and constant high glucose on oxidative stress of bovine retinal capillary pericytes

Objective To compare the effects of intermittent and constant high glucose on oxidativestress of bovine retinal capillary pericytes (BRPs). Methods BRPs were cultured for 6 days under constant different concentration glucose ( 15 mmol/L,25 mmoL/L), intermittent high glucose at the concentration of (5.5-15 mmol/L,5.5-25mmol/L ) and control group(5.5 mmol/L). TBA method was used to detect the contents of MDA. Xanthine oxidase method was used to detect the SOD activities. Results The MDA content/SOD activity of BRPs in intermittent and constant high glucose were higher than those in the control group( P ＜ 0.05 ). The changes were correlated positively with the concentrations of glucose ( P ＜ 0.01 ) and the amplitude of fluctuation ( P ＜0.05 ). The MDA content/SOD activity of BRPs in intermittent high glucose (5.5-15 mmol/L) were higher than those in the constant high glucose ( 15 mmol/L), the MDA content/SOD activity of BRPs in constant high glucose(25 mmol/L)were higher than those in the intermittent high glucose (5.5-25 mmol/L). Conclusion In certain glucose concentration range,the intermittent high glucose has astronger action on oxidative stress of BRPs than constant high glucose. Beyond a certain concentration of glucose, the constant high glucose has a stronger action on oxidative stress of BRPs than intermittent high glucose.