Histidine and carnosine delay diabetic, deterioration in mice and protect human low density lipoprotein against oxidation and glycation

In vivo effects of histidine and camosine against diabetic deterioration in diabetic Balb/cA mice were studied. Histidine and camosine at 0.5, 1 g/l were added into drinking water. After 4 weeks intake of these agents, the content of histidine and camosine in plasma, heart and liver significantly elevated (P < 0.05). The intake of these agents significantly decreased plasma glucose and fibronectin levels (P < 0.05); however, only 1 g/l histidine and camosine treatments significantly increased insulin level (P < 0.05) in diabetic mice. Triglyceride level in heart and liver was dose-dependently reduced by histidine or camosine treatments (P < 0.05); however, only 1 g/l histidine and camosine treatments significantly reduced cholesterol level in heart and liver (P < 0.05). The administration of histidine or camosine significantly enhanced catalase activity and decreased lipid oxidation levels in kidney and liver (P < 0.05); however, only 1 g/l histidine and camosine treatments significantly increased glutathione peroxidase activity (P < 0.05). The increased interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha in diabetic mice were significantly suppressed by the intake of histidine or camosine (P < 0.05). In human low density lipoprotein, histidine or camosine showed dose-dependently suppressive effect in glucose-induced oxidation and glycation (P < 0.05). These data suggest that histidine and carnosine are potential multiple-protective agents for diabetic complications prevention or therapy. (c) 2005 Elsevier B.V. All rights reserved.