Perinatal Nicotine Exposure Increases Obesity Susceptibility in Adult Male Rat Offspring by Altering Early Adipogenesis.

Abstract

The present study aims to evaluate whether perinatal nicotine (NIC) exposure increases obesity susceptibility in adult male rat offspring by altering early adipogenesis. NIC was sc administered (2.0 mg/kg per day) to pregnant rats from gestational day 9 to the time of weaning (postnatal day 28). At weaning, NIC-exposed male pups had an increased body weight and inguinal sc fat mass and a decreased average cell area of adipocyte, which was accompanied by an overexpression of adipogenic and lipogenic genes in the epididymal white adipose tissue. Additionally, the hepatic lipogenic gene levels from NIC-exposed male pups were also affected. At 12 and 26 weeks of age, body weight and fat mass were increased, whereas there was no change in food intake in NIC-exposed male offspring. Adipogenic and lipogenic genes, glucose transporter 4, and leptin mRNA levels were increased, whereas adiponectin mRNA levels were decreased in the epididymal white adipose tissue of NIC-exposed males. The hepatic lipogenic gene expression of NIC-exposed males was increased. NIC-exposed male offspring showed normal glycemia and a higher serum insulin level, homeostasis model assessment of insulin resistance, and homeostasis model assessment of β-cell function. Furthermore, the NIC-exposed male offspring showed higher serum lipids and Castelli index I and lower nonesterified fatty acid. At 26 weeks, in the ip glucose and insulin tolerance tests, the glucose clearance was delayed, and the area under the curve was higher in the NIC-exposed male offspring. In conclusion, perinatal NIC exposure increased obesity susceptibility in adult male rat offspring by altering early adipogenesis.