Diabetic Nephropathy - Treatment

Taurine - updated: 15 March 2008

The role of Advanced Glycation End products (AGEs)

Nonenzymatic reactions between sugars and the free amino groups on proteins, lipids, and nucleic acids result in molecular dysfunction through the formation of advanced glycation end products (AGE). AGE have a wide range of chemical, cellular, and tissue effects through changes in charge, solubility, and conformation that characterize molecular senescence. Drugs that either inhibit the formation of AGE or break AGE-induced cross-links have been shown to be renoprotective in experimental models of diabetic nephropathy.

Stimulation of glucose utilization and inhibition of protein glycation and AGE products by taurine.

Acta Physiol Scand. 2004 Jul;181(3):297-303

Nandhini AT, Thirunavukkarasu V, Anuradha CV.

AIM: Pathological effects of the process of non-enzymatic glycation of proteins are reflected in chronic complications of diabetes mellitus. We investigated the antiglycating effect of taurine in high fructose fed rats in vivo and the inhibiting potency of taurine in the process of in vitro glycation. Additionally, we investigated whether taurine enhances glucose utilization in the rat diaphragm. METHODS: Rats fed a high fructose diet (60% total calories) were provided 2% taurine solution for 30 days. The effects of taurine on plasma glucose, fructosamine, protein glycation and glycosylated haemoglobin in high fructose rats were determined. For in vitro glycation a mixture of 25 mm glucose and 25 mm fructose was used as glycating agent, bovine serum albumin as the model protein and taurine as the inhibitor. Incubations were carried out in a constant temperature bath at 37 degrees C for 3-30 days. Amadori products and advanced glycation end products (AGEs) formed were measured. In vitro utilization of glucose was carried out in the rat diaphragm in the presence and absence of insulin in which taurine was used as an additive. RESULTS: The contents of glucose, glycated protein, glycosylated haemoglobin and fructosamine were significantly lowered by taurine treatment to high fructose rats. Taurine prevented in vitro glycation and the accumulation of AGEs. Furthermore, taurine enhanced glucose utilization in the rat diaphragm. This effect was additive to that of insulin and did not interfere with the action of insulin. CONCLUSIONS: These results underline the potential use of taurine as a therapeutic supplement for the prevention of diabetic pathology.

Publication Types:

• Animal Study

Taurine prevents collagen abnormalities in high fructose-fed rats

Indian J Med Res. 2005 Aug;122(2):171-7

BACKGROUND & OBJECTIVE: Accumulation of collagen and changes in its physiochemical properties contribute to the development of secondary complications of diabetes. We undertook this study to see the effects of taurine on the content and characteristics of collagen from tail tendon of rats fed with high fructose diet. METHODS: The rats were divided into four groups of six each: control group (CON), taurine-supplemented control group (CON+TAU), taurine supplemented (FRU+TAU) and not supplemented fructose-fed group (FRU). The physico-chemical properties of collagen isolated from the tail tendon were studied. RESULTS: Fructose administration caused accumulation of collagen in tail tendon. Enhanced glycation and advanced glycation end products (AGE)-linked fluorescence together with alterations in aldehyde content, solubility pattern, susceptibility to denaturing agents and shrinkage temperature were observed in fructose-fed rats. Elevated b component of type I collagen was evidenced from the SDS gel pattern of collagen from the fructose-fed rats. Simultaneous administration of taurine alleviated these changes. INTERPRETATION & CONCLUSION: Taurine administration to fructose-rats had a positive influence on both quantitative and qualitative properties of collagen. The results of the present study suggested a role for the action of taurine in delaying diabetic complications and the possible use of taurine as an adjuvant therapeutic measure in the management of diabetes and its complications.

Publication Types:

• Animal Study

The low-AGE content of low-fat vegan diets could benefit diabetics - though concurrent taurine supplementation may be needed to minimize endogenous AGE production

Med Hypotheses. 2005;64(2):394-8

McCarty MF.

Increased endogenous generation of advanced glycation endproducts (AGEs) contributes importantly to the vascular complications of diabetes, in part owing to activation of the pro-inflammatory RAGE receptor. However, AGE-altered oligopeptides with RAGE-activating potential can also be absorbed from the diet, and indeed make a significant contribution to the plasma and tissue pool of AGEs; this contribution is especially prominent when compromised renal function impairs renal clearance of AGEs. Perhaps surprisingly, foods rich in both protein and fat, and cooked at high heat, tend to be the richest dietary sources of AGEs, whereas low-fat carbohydrate-rich foods tend to be relatively low in AGEs. Conceivably, this reflects the fact that the so-called "AGEs" in the diet are generated primarily, not by glycation reactions, but by interactions between oxidized lipids and protein; such reactions are known to give rise to certain prominent AGEs, such as epsilonN-carboxymethyl-lysine and methylglyoxal. Although roasted nuts and fried or broiled tofu are relatively high in AGEs, low-fat plant-derived foods, including boiled or baked beans, typically are low in AGEs. Thus, a low-AGE content may contribute to the many benefits conferred to diabetics by a genuinely low-fat vegan diet. Nonetheless, the plasma AGE content of healthy vegetarians has been reported to be higher than that of omnivores - suggesting that something about vegetarian diets may promote endogenous AGE production. Some researchers have proposed that the relatively high-fructose content of vegetarian diets may explain this phenomenon, but there so far is no clinical evidence that normal intakes of fructose have an important impact on AGE production. An alternative or additional possibility is that the relatively poor taurine status of vegetarians up-regulates the physiological role of myeloperoxidase-derived oxidants in the generation of AGEs - in which case, taurine supplementation might be expected to suppress elevated AGE production in vegetarians. Thus, a taurine supplemented low-fat vegan diet may be recommended as a strategy for minimizing AGE-mediated complications in diabetics and in patients with renal failure.

Publication Types:

• Medical Hypotheses

Publication Types:

• Review