Sexual Dimorphism in Clock Genes Expression in Human Adipose Tissue

Background This study was carried out to investigate whether sex-related differences exist in the adipocyte expression of clock genes from subcutaneous abdominal and visceral fat depots in severely obese patients. Methods We investigated 16 morbidly obese patients, eight men and eight women (mean age 45 ± 20 years; mean BMI 46 ± 6 kg/m 2 ), undergoing laparoscopic gastric bypass surgery. Biopsies were taken as paired samples [subcutaneous and visceral adipose tissue (AT)] at the beginning of the surgical process at 11:00 h in the morning. Metabolic syndrome features such as waist circumference, plasma glucose, triglycerides, total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were also studied. The expression of clock genes ( PER2 , BMAL1 , and CRY1 ) was measured by quantitative real-time PCR, Western blot, and immunohistochemical analysis. Results Gene expression was significantly higher in women than in men for the three genes studied in both ATs ( P