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

Ebrahim Abbasi Oshaghi, Arash Noori Sorkhani, Ali Rezaei

Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran..
Department of Laboratory Science, Islamic Azad University, Borūjerd, Iran.

DOI: 10.4236/fns.2012.32037                

Abstract

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.

Keywords

Walnut; Cholesterol; SREBP-1c; PPARα

Conflicts of Interest

The authors declare no conflicts of interest.

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