丙酮酸对糖尿病大鼠视网膜氧化损伤及超微结构的影响

目的:研究糖尿病大鼠视网膜病变过程中视网膜组织学和氧化应激的变化,以及丙酮酸的对抗作用。方法:将80只Wistar大鼠分成3组:对照组(20只),模型组(30只),治疗组(30只)。模型组和治疗组用STZ诱导糖尿病,治疗组在大鼠饲料和饮水中添加2%丙酮酸。观察大鼠的血糖、体质量变化,并在造模后12wk观察3组大鼠视网膜组织中GSH-Px、MDA和Na+-K+-ATP酶水平及其超微结构改变。结果:模型组和对照组相比,体质量显著下降,视网膜中GSH-Px和ATP酶活性显著下降,MDA水平显著升高,视网膜超微结构有显著改变;治疗组和模型组相比,血糖没有显著改变,视网膜组织中GSH-Px和ATP水平升高,MDA水平下降,视网膜超微结构病变相对较轻。结论:丙酮酸可以减轻氧化应激反应,改善视网膜的能量代谢,延缓视网膜病变的发展。

Effects of pyruvate on retinal oxidative damage and retinal ultrastructure in diabetic rats

AIM:To investigate the changes of retinal histology and oxidative stress in diabetic retinopathy and its reversal by pyruvate in diabetic rats.

METHODS:Eighty Wistar rats were divided into 3 groups: control group(20 rats), model group(30 rats)and treatment group(30 rats). After streptozotocin(STZ)induced diabetes mellitus in the model group and the treatment group, the treatment group received 2% pyruvate in diet and drinking. The changes of body weight and blood glucose were observed and the changes of glutathione peroxidase(GSH-PX), malonie dialdehyde(MDA), and Na⁺-K⁺-ATPase levels of retinal tissue and retinal ultrastructure were investigated in three groups at 12wk after occurrence of diabetes.

RESULTS:Compared with control group, the body weight of the model group were significantly decreased, the activities of GSH-PX and ATP in the retina of diabetic rats were significantly lower, the MDA was signigicantly higher and significant changes occurred in retinal ultrastructure. Compared with model group, the blood glucose of the treatment group had no significant changes. However, the activities of GSH and ATP in the retina of diabetic rats were higher, the MDA was lower and the retinal ultrastructure was comparatively mild.

CONCLUSION:Pyruvate can alleviate oxidatie stress reaction, improve the energy metabolism of retina, and delay the development of retinopathy.