Effects of Walnut on Lipid Profile as Well as the Expression of Sterol-Regulatory Element Binding Protein-1c(SREBP-1c) and Peroxisome Proliferator Activated Receptors α (PPARα) in Diabetic Rat


Diabetes Mellitus has appeared as a universal burden. Studies have reported that mortality from Coronary Heart Disease (CHD) in diabetic patients is 2 - 4 times higher than nondiabetics. In this respect, walnut is a treatment which has beneficial effects on CHD risk factors. PPARα and SREBP-1c play an important role in the regulation of lipid metabolism. This study was aimed to evaluate the effects of walnut on lipid profile as well as SREBP-1c and PPARα protein levels in rats. Animals were randomly divided into 3 groups (n = 6); Group 1: Received chow only (control), Group 2: Diabetic rats + chow, Group 3: Diabetic rats + chow supplemented with 4% of whole walnuts. After four weeks rats were sacrificed, blood was collected; lipid profiles as well as SREBP-1c and PPARα protein levels were determined. Compared with diabetic rats walnut significantly decreased serum cholesterol (P < 0.01), LDL-c (P < 0.01), triglyceride (P < 0.001) and VLDL-c (P < 0.001) and also increased HDL-c (P < 0.05) compared with diabetic. Moreover, SREBP-1c protein level significantly decreased (P < 0.05) and PPARα significantly increased in walnut group compared with diabetic group (P < 0.05). The findings showed that walnut administration in diet clinically decreases atherosclerosis risk factors. Lipid profile reduction might be due to the rise of PPARα and the reduction of SREBP-1c by this medical treatment in liver.

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E. Oshaghi, A. Sorkhani and A. Rezaei, "Effects of Walnut on Lipid Profile as Well as the Expression of Sterol-Regulatory Element Binding Protein-1c(SREBP-1c) and Peroxisome Proliferator Activated Receptors α (PPARα) in Diabetic Rat," Food and Nutrition Sciences, Vol. 3 No. 2, 2012, pp. 255-259. doi: 10.4236/fns.2012.32037.

Conflicts of Interest

The authors declare no conflicts of interest.


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