DEVELOPMENTAL LOW-DOSE EXPOSURE TO BISPHENOL A ALTERS ADIPOCYTE CELL DENSITY AND INDUCES HYPERLIPIDEMIA IN FISCHER 344 RATS

Sammanfattning: ABSTRACT Background: Developmental exposure to endocrine disrupting chemical (EDC), such as Bisphenol A (BPA) has been shown to affect the health during early stages in life. Aim: To assess whether developmental low-dose exposure to BPA alters adipocyte distribution and blood lipid levels in Fischer 344 (F344) rats. Method: Pregnant F344 rats were exposed to BPA via their drinking water from gestational day 3.5 throughout lactation. Doses given were one below the current European Food Safety Authority´s preliminary tolerable daily intake (TDI) of 4 µg BPA/kg bw/day, 0.5 [lower dose, Ld] and one equal to the previous TDI; 50 [higher dose, Hd] µg BPA/kg bw/day. Half the offspring was sacrificed at 5, and half at 52 weeks of age. Body weight was registered, and plasma lipid levels were analyzed. Inguinal white adipose tissue (iWAT) was weighed, Oil red O-stained and analyzed histologically. Results: Five-week-old Ld males and females Hd exhibited significantly higher triglyceride levels (31%, p<0.01; 41%,p<0.05, respectively) compared to control. Total cholesterol was borderline significantly increased (9%, p=0.0554) in 5-week-old Ld males, compared with control. Adipocyte cell density in the 5-week-old offspring was significantly increased; Ld female rats had increased cell density compared to control and Hd (22% and 23%,p<0.05, respectively), whereas the cell density of Hd males increased compared to Ld (29%, p<0.05). In the 52-week-old offspring blood lipid levels and iWAT cell density were not significantly affected. Conclusions: Results of the present study supports that developmental low-dose BPA exposure contributes to elevated triglyceride levels in 5-week-old animals.