Examination of the effect of homocysteine on CD36 gene expressions in the adipose tissue of normal and obese mice

Obesity is a disease deriving from energy in the body absorbed with foods exceeding energy expended. Homocysteine (Hcy) is an amino acid that forms during intracellular demethylation of the essential amino acid methionine. Cluster of differentiation 36 (CD36) is a member of the class B scavenger receptor family. Peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer binding protein alpha (C/EBPα) are transcription factors that activate several genes associated with adipocyte function and that also regulate the expression of CD36. The purpose of this study was to examine, in vivo, the effect of Hcy, associated with several pathological events, on CD36, PPARγ and C/EBPα gene expression in epididymal adipose tissue obtained from BALB/c mice with an obesity model induced with a high-calorie diet. Four groups, each containing six mice, were established in our study: Group 1: Standard chow and drinking water, Group 2: High fat content chow and drinking water, Group 3: Standard chow and drinking water with added Hcy, Group 4: High fat content chow and drinking water with added Hcy. Epididymal adipose tissue specimens were collected after mice in each group had been fed as described above for 3 months. CD36, PPAR-γ and C/EBPα gene expression levels in adipose tissue specimens were determined using the RT-PCR method. CD36 gene expression increased significantly in adipose tissue from obese mice (p=0.003), while Hcy statistically significantly reduced CD 36 gene expression in mice receiving both standard chow and high-fat chow compared to mice that were not given Hcy (p 0.002 and 0.002, respectively). PPAR-γ and C/EBPα gene expression levels decreased significantly in all groups compared to the group receiving standard chow (p<0.05). Additionally, with Hcy supplementation both PPARγ and C/EBPα gene expression levels proceeded at lower levels compared to their own controlsIn conclusion, one of the possible factor for hyperhomocysteinemia to ben an independent risk factor in cardiovascular diseases can be attributed to reduction of CD36 gene expression by Hcy in adipose tissue.