Phenamil enhances the adipogenic differentiation of hen preadipocytes

A study was conducted to examine the effect of phenamil on adipogenic differentiation and expression of key adipogenic transcripts in hen preadipocytes. Preadipocytes were isolated from 20-week old Single Comb White Leghorn hens (Gallas gallus, Lohman strain). The experiment lasted for 48 h and had six treatments. Non-treated control (C) cells, cells treated with dexamethasone, 3-isobutyl-1-methylxanthine, insulin, and oleic acid (DMIOA) (T1), DMIOA+15 mu M phenamil (T2), DMIOA+30 mu M phenamil (T3), 15 mu M phenamil alone (T4), and 30 mu M phenamil alone (T5). Neutral lipid accumulation and the mRNA expression of key adipogenic transcripts were measured in all treatments and compared. Lipid accumulation was detected in T1, T2, and T3 only. Expression of peroxisome proliferator receptor-activator gamma 2 (PPAR gamma 2), the core enhancer binding protein a (C/EBP alpha), C/EBP beta, fatty acid binding protein 4 (FABP4), and lipoprotein lipase (LPL) as well as ETS variant 4 (ETV4) and 5 was higher (P<0.05) in T2, T3, T4, and T5 compared to C. Expression of these transcripts was higher (P<0.05) in T2 and T3 compared to T4 and T5. The core enhancer binding protein alpha, C/EBP beta, and FABP4 were highly expressed (P<0.05) in T1 compared to C. However, the expression of PPAR gamma 2, LPL, and ETV4 and ETV5 was not significantly different. Expression of C/EBP alpha, C/EBP beta, and FABP4 was higher (P<0.05) in T2 and T3 compared to T1. Expression of sterol regulatory element binding protein 1 (SREBP1) and leptin receptor (LEPR) was not significantly different among the treatments. In conclusion, phenamil enhances DMIOA-induced adipogenic differentiation of hen preadipocytes but does not induce adipogenesis by itself.