Effects of antioxidants on nerve and vascular dysfunction in experimental diabetes.

نویسندگان

  • N E Cameron
  • M A Cotter
چکیده

Reactive oxygen species (ROS) are elevated by metabolic changes in diabetes, including autoxidation and increased advanced glycation. Endogenous protection by the glutathione redox cycle is also compromised by the competing NADPH requirement of elevated polyol pathway flux. Antioxidant treatment strategies prevent or reverse nerve conduction velocity (NCV) deficits in diabetic rats. These include lipophilic scavengers such as butylated hydroxytoluene, probucol and vitamin E, more hydrophilic agents like alpha-lipoic acid and acetyl cysteine, and transition metal chelators that inhibit autoxidation. In the long-term, elevated ROS cause cumulative damage to neurons and Schwann cells, however, they also have a deleterious effect on nerve blood flow in the short term. This causes endoneurial hypoxia, which is responsible for early NCV deficits. Antioxidant treatment corrects the blood flow deficit and promotes normal endoneurial oxygenation. ROS cause antioxidant-preventable vascular endothelium abnormalities, neutralizing nitric oxide mediated vasodilation and increasing reactivity to vasoconstrictors. Unsaturated fatty acids are a major target for ROS and essential fatty acid metabolism is impaired by diabetes. Gamma-linolenic acid stimulates vasodilator prostanoid production, and there are marked synergistic interactions between gamma-linolenic acid and antioxidants. This has encouraged the development of novel drugs such as ascorbyl-gamma-linolenic acid and gamma-linolenic acid-lipoic acid with enhanced therapeutic potential.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Effect of Linalool on the Activity of Glyoxalase-I and Diverse Glycation Products in Rats with Type 2 Diabetes

Background and purpose: Hyperglycemia contributes to type 2 diabetes and diabetes vascular complications by reduction of the activity of glyoxalase-I (GLO-I) and elevation of glycation, oxidative stress, and inflammatory markers. Linalool is reported to have beneficial effects on glucose metabolism in animal models of diabetes, so, this study aimed at investigating the effect of linalool on the...

متن کامل

Ensete superbum ameliorates renal dysfunction in experimental diabetes mellitus

Objective(s):Hyperglycemia mediated oxidative stress plays a key role in the pathogenesis of diabetic complications like nephropathy. In the present study, we evaluated the effect of ethanolic extract of Ensete superbum seeds (ESSE) on renal dysfunction and oxidative stress in streptozotocin-induced diabetic rats. Materials and Methods:Glucose, HbA1c, total protein, albumin, renal function mar...

متن کامل

Ascorbic Acid Improves Vascular Permeability in Experimental-Induced Diabetic Rats

Background: The most devastating manifestations of diabetes mellitus are vascular complications. Although there are many factors involved in the pathogenesis of diabetic vasculopathy, many studies suggest a role for glucose–induced oxidative stress. Studies in animal models, have demonstrated that the administration of antioxidants restores normal endothelial functions. The study was designed t...

متن کامل

Histologic and Histomorphometric Study on the Effect of Hydro-Alcoholic Aloe Vera Extract on Tissue Formation of Sciatic Nerve in Diabetic Male Rats

 Background & Objective: Diabetes mellitus affects the metabolism of carbohydrates, lipids, and proteins, which leads to the dysfunction of the central and peripheral nervous system. Reports suggest that Aloe Vera has anti-diabetic effects. Therefore, this study was carried out to determine the effect of hydro alcoholic extract of Aloe Vera on Sciatic nerve of the diabetic rats.Materials ...

متن کامل

Early neural and vascular dysfunctions in diabetic rats are largely sequelae of increased sorbitol oxidation.

These experiments were undertaken to assess the importance of cytoplasmic (c) sorbitol oxidation versus mitochondrial (m) pyruvate oxidation in mediating neural and vascular dysfunction attributable to hyperglycemia in diabetic rats. Increased oxidation of sorbitol is coupled to enzymatic reduction of free oxidized NAD(+)c to reduced NADHc, manifested by an increased ratio of NADH to NAD(+)c. L...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Diabetes research and clinical practice

دوره 45 2-3  شماره 

صفحات  -

تاریخ انتشار 1999