Quantitative investigation of the effects of high-fat diet on white and brown fat tissues in the prenatal and postnatal period

Objective: Obesity is often associated with an increase in white adipose tissue (WAT), while brown adipose tissue (BAT) regulates energy expenditure and thermogenesis through Uncoupling protein-1 (UCP-1) protein. Our aim was to examine the effects of a high-fat diet (HFD) during prenatal and postnatal periods on the structural characteristics of WAT and BAT, and UCP-1 activation. Method: Eight female Wistar-Albino rats were divided into standard diet (SD) and HFD groups after mating. After weaning, the offspring were divided into SD and HFD subgroups (SDSD, SDHF, HFSD, HFHF). On the postnatal 63rd day, the animals were sacrificed and the samples were collected. Levels of adiponectin, leptin, TNF-α, IL-6, and IL-1β were measured using ELISA. WAT and BAT were histologically examined with Hematoxylin-Eosin staining and stereological analyses were performed. UCP-1 level in BAT was determined using Western Blot. Results: The present results revealed that the offspring fed with HFD by their mother had higher body weight and abdominal diameter, lower IL-1β and IL-6, and adiponectin levels. The current results also showed that the offspring fed with HFD after weaning and those whose mothers were fed with SD diet had higher UCP-1 levels. Consumption of HFD by mother and offspring resulted in an increase in adipocyte diameter and a decrease in the number of adipocytes per unit in WAT, while different effects of HFD were noted in BAT of the mother and offspring fed with HFD. Conclusion: HFD appeared to increase obesity risk by affecting adipocyte morphology. Understanding the effects of HFD both during maternal and developmental periods is critical to regulate early nutrition programs in terms of ensuring healthy growth, development and thereby preventing obesity.