The purpose of this study was to clarify the effect of cacao polyphenol（CP） intake on liver and kidney tissue in obese type 2 diabetes model rats. Five-week-old male obese type 2 diabetes model rats were fed for 4 weeks. The experimental diet consisted of a high-fat diet (control group, n=6) and a CP-supplemented diet (CP group, n=6). Liver lipids concentration and oxidative stress were measured in liver tissue. The control group had many lipid droplets of various sizes, but the CP group had almost no lipid droplets. In kidney tissue, the control group had a slightly wider Bowman's space and lobulated glomeruli. In the CP group, the glomeruli were almost normal in size, and there was little increase in mesangial cells and matrix. When CP was administered to obese type 2 diabetes model rats, the liver cholesterol concentration and oxidative stress were reduced (p<0.01, p<0.01). It was also suggested that cocoa polyphenols suppress fat accumulation in liver tissue and damage to mesangial cells in kidney tissue. These results suggest that cocoa polyphenol intake may suppress the early stages of obesity-related type 2 diabetic nephropathy and may be useful in preventing obesity and diabetes.

The purpose of this study was to clarify the effects on oxidative stress and the kidney tissues of obese type2 diabetes model rats when catechins were ingested. 5-week-old obese type 2 diabetes model male rats were kept for 4 weeks. A normal diet was fed to a control group (n=6), while an experimental catechin group (n=6) was fed catechin. Posterior subcutaneous abdominal fat weight and oxidative stress were measured, and kidney tissues were observed. Posterior subcutaneous abdominal fat weight and oxidative stress were significantly lower in the catechin group than in the control group. In the kidney tissues, the mesangial region in the control group was larger than in the capillary space, and the glomerulus was lobulated. The mesangial area in the catechin group was almost equivalent to the capillary space. Ingestion of catechin in obese type 2 diabetes model rats reduced fat accumulation and oxidative stress. It has also been suggested that catechin suppresses damage to mesangial cells in kidney tissue. Catechin intake likely suppresses oxidative stress and diabetic nephropathy inflammation, and it could be useful for the prevention of diabetes.