Jain R M, Bulakh P M
Department of Biochemistry, B.J. Medical College, 411001 Pune.
Indian J Clin Biochem. 2003 Jan;18(1):91-5. doi: 10.1007/BF02867672.
Cataract is one of the leading causes of visual disability often leading to blindness in the elderly population. One of the causes is oxidation of proteins present in lens, by hydrogen peroxide (H(2)O(2)). In the present study 100 goat lenses were analyzed to determine the protective efficacy of ketoacids, against the oxidative insult by H(2)O(2). The ketoacids used were (pyruvate, alpha ketoglutarate and oxaloacetate), that are constantly produced endogenously. The lenses were incubated as control and experimental groups in TC-199 media for 72 hrs. H(2)O(2) concentration of 10mM was used to induce cataract. The biochemical parameters measured were levels of malondialdehyde (MDA), a lipid peroxidation product and activity of glutathione peroxidase (G-Px), an enzymatic antioxidant. The results showed a significant increase in the levels of MDA and significant decrease in the activity of G-Px in the cataractous lenses as compared to control. After addition of ketoacids (pyruvate (10mM), alpha ketoglutarate (20mM) and oxaloacetate (20mM)) separately, the levels of MDA decreased significantly and the activity of G-Px increased significantly. The results suggest that the ketoacids can be very promising antioxidants for the treatment of cataract. They may also be useful in treating other disabilities related to acute and chronic oxidative stress.
白内障是导致视力残疾的主要原因之一，常致使老年人群失明。原因之一是过氧化氢（H₂O₂）使晶状体中的蛋白质发生氧化。在本研究中，分析了100个山羊晶状体，以确定酮酸对H₂O₂氧化损伤的保护效果。所使用的酮酸为（丙酮酸、α-酮戊二酸和草酰乙酸），它们是体内持续产生的。将晶状体作为对照组和实验组在TC-199培养基中孵育72小时。使用10mM的H₂O₂浓度诱导白内障形成。所测量的生化参数为脂质过氧化产物丙二醛（MDA）的水平以及酶抗氧化剂谷胱甘肽过氧化物酶（G-Px）的活性。结果显示，与对照组相比，白内障晶状体中MDA水平显著升高，G-Px活性显著降低。分别添加酮酸（丙酮酸（10mM）、α-酮戊二酸（20mM）和草酰乙酸（20mM））后，MDA水平显著降低，G-Px活性显著升高。结果表明，酮酸可能是治疗白内障非常有前景的抗氧化剂。它们也可能有助于治疗与急性和慢性氧化应激相关的其他残疾。
