Modification of Biochemical Derangements and VEGF Secretion May Prevent Diabetic Retinopathy (DR): An Advance Study

Abstract

Unutilized, enormous intracellular glucose in insulin-nondependent tissues, including retina, leads to several consequences: (i) increased formation of advanced glycation end products, (ii) activation of polyol pathway, (iii) anaerobic glycolysis, (iv) glutamate toxicity, (v) lipid peroxidation and oxidative stress, and all of these, finally, resulting in convergence to up regulation of antigenic VEGF and VEGFR2, the crucial player in the development of DR. The purpose of the present pilot study is to assess the effects of one kind of intervention on the development of DR: supplementation of B-vitamins (B1, B2, B3, B5 and B6), vitamin C and vitamin E on amelioration of biochemical derangements related to development of DR. 400 diagnosed type 2 diabetic patients were identified for the study, of which subjects were randomised 1:1 to receive oral antidiabetic medication along with B-vitamins, vitamin C and vitamin E or only antidiabetic medication to give the study and controlled population in this unblended randomized trial since December 2004 to December 2017. The following preliminary tasks were completed: firstly, baseline detailed fundoscopic examinations were enough to exclude the presence of retinopathy. Secondly, had baseline biochemical parameters like bllod concentration of NAD+, NADH, advanced glycation end products (AGEs), malondialdehyde (MDA), VEGF and VEGFR2 determined? Lastly, yearly fundoscopic examinations were documented to detect the features of DR. These efforts revealed the following findings: 32 among 187 (17.11%) patients who received supplementation with B-vitamins, vitamin C and vitamin E developed very mild microangiopathy; whereas 92 patients among 200 (46%) controlled ones developed mild to moderate non proliferative diabetic retinopathy (NPDR). 13 patients of the study group who didn’t follow up were counted as lost from the observation of the study. The findings lead to this conclusion: Glycolysis and citric acid cycle should run uninterruptedly by supplementation of precursors of oxidized cofactors and antioxidants to prevent biochemical derangements which lead to increased expression of VEGF.