The aim of the study was to determine the effect of high-fat diets and dietary fatty acids composition on nuclear androgen receptors protein levels (AR) in rat ventral prostate epithelial and stroma part.
The study was conducted on 30 male Wistar rats with initial body mass 250±10 g, divided into five groups fed four experimental and one reference diets during three weeks. Experimental semi-synthetic, high-fat (20% w/w) diets were as follows: diet A contained grapes-seed oil reach in PUFA n-6, diet B lard reach in SFA, diet C rapeseed oil reach in MUFA n-9 and diet D fish oil reach in PUFA n-3. Reference rat group (E) was fed low-fat (3% w/w) standard pellets. Animals were kept in individual cages under a 12:12 h light:dark regime, with free access to food and water. After experiment, rats were anesthetized by peritoneal Thiopental injection and sacrificed by cardiac puncture. The ventral prostate was dissected out and immediately fixed in 10% formalin and stored in paraffin blocks. All procedures were approved by the Local Animal Care and Use Committee in Warsaw. AR in rat prostate tissues were determined by immunohistochemisty using polyclonal antibody (PC-167, Calbiochem).
Obtained results showed statistically significant influence (P≤0.001) of dietary fat type on AR in prostate parts. In all experimental groups in comparison to reference group we observed a significantlly lower AR in epithelial part, whereas in stromal part no significant AR changes between all dietary groups were found. Moveover, in group B in comparison to A, C and D groups the highest AR in epithelial parts were stated.
To sumarize, it seems that consumption of high-fat diets can induce protein AR degradation or modify AR gene expression in rat ventral prostate epithelium and that high consumption of SFA increases AR in this prostate tissue.