Vîrgolici Bogdana, Stoian Irina, Muscurel Corina, Mărăcine Magda, Moraru C, Dinu Veronica
Biochemistry Department, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
Rom J Intern Med. 2007;45(1):59-65.
Dysfunction of the lens due to opacification is called cataract. Senile cataract is associated with old age. It is estimated that the need for cataract extractions would be diminished by half if onset of cataract would be delayed by only ten years. It thus appears crucial to have a better characterization of the etiology of cataract to detect modifiable factors. It seems that oxidative stress may play an important role in cataractogenesis. Also, it was demonstrated that some plasma constituents correlate with human cataract location.
We supposed that in senile cataract the oxidative insult may be systemic and not only at the lens level. The aim of our study was to evaluate the blood redox status in cataractous patients aged between 50-65.
The blood samples were collected from 15 patients with pure nuclear cataract and/or posterior subcapsular cataract, without metabolic or somatic diseases and from 15 age and sex matched controls. Carbonyl content of plasma proteins was evaluated with 2,4-dinitro-phenyl-hydrazine method. The a-oxoaldehydes were measured in the presence of Girard T reactive. The lipid peroxides concentration was assessed measuring malondialdehyde concentration using thiobarbituric acid. For the other plasma parameters we used kits.
The levels of plasma protein carbonyls and malondialdehyde were significantly increased in the cataract group. The plasma levels of: total proteins, globulins, total thiols, fasting glucose, triglycerides and alpha-oxoaldehydes were not modified comparing the groups. Plasma concentrations of albumin and cholesterol were significantly decreased.
The study underlies the presence of an increased plasma oxidative stress in cataractous patients. The abnormal oxidative stress parameters are linked to the premature development of senile cataract. Preventive therapy in order to delay the onset of senile cataract requires more research work on plasma oxidative stress markers.
晶状体因混浊而出现的功能障碍称为白内障。老年性白内障与衰老有关。据估计，如果白内障的发病仅延迟十年，白内障摘除的需求将减少一半。因此，更好地描述白内障的病因以发现可改变的因素似乎至关重要。氧化应激似乎可能在白内障形成中起重要作用。此外，已证明某些血浆成分与人类白内障的位置相关。
我们推测在老年性白内障中，氧化损伤可能是全身性的，而不仅仅局限于晶状体水平。我们研究的目的是评估年龄在50 - 65岁之间的白内障患者的血液氧化还原状态。
从15例患有单纯核性白内障和/或后囊下白内障、无代谢或躯体疾病的患者以及15例年龄和性别匹配的对照组中采集血样。采用2,4 - 二硝基苯肼法评估血浆蛋白的羰基含量。在存在吉拉德T试剂的情况下测量α - 氧代醛。使用硫代巴比妥酸测量丙二醛浓度来评估脂质过氧化物浓度。对于其他血浆参数，我们使用试剂盒。
白内障组血浆蛋白羰基和丙二醛水平显著升高。两组比较，血浆中总蛋白、球蛋白、总巯基、空腹血糖、甘油三酯和α - 氧代醛的水平未发生改变。白蛋白和胆固醇的血浆浓度显著降低。
该研究表明白内障患者血浆氧化应激增加。异常的氧化应激参数与老年性白内障的过早发生有关。为了延迟老年性白内障的发病而进行的预防性治疗需要对血浆氧化应激标志物进行更多研究工作。
