Modulation of Sirt1 by resveratrol and nicotinamide alters proliferation and differentiation of pig preadipocytes

Abstract

Sirt1, a NAD + -dependent histone deacetylase, may regulate senescence, metabolism, and apoptosis. In this study, primary pig preadipocytes were cultured in DMEM/F12 medium containing 10% fetal bovine serum (FBS) with or without reagents affecting Sirt1 activity. The adipocyte differentiation process was visualized by light microscopy after Oil red O staining. Proliferation and differentiation of preadipocytes was measured using methylthiazolyldiphenyl-tetrazolium bromide (MTT) and Oil red O extraction. Expression of Sirt1, FoxO1, and adipocyte specific genes was detected with semi-quantitive RT-PCR. The results showed that Sirt1 mRNA was widely expressed in various pig tissues from different developmental stages. Sirt1 mRNA was expressed throughout the entire differentiation process of pig preadipocytes. Resveratrol significantly increased Sirt1 mRNA expression, but decreased the expression of FoxO1 and adipocyte marker gene PPARc2. Resveratrol significantly inhibited pig preadipocyte proliferation and differentiation. Nicotinamide decreased the expression of Sirt1 mRNA, but increased the expression of FoxO1 and adipocyte specific genes. Nicotinamide greatly stimulated the proliferation and differentiation of pig preadipocytes. In conclusion, these results indicate that Sirt1 may modulate the proliferation and differentiation of pig preadipocytes. Sirt1 may down-regulate pig preadipocytes proliferation and differentiation through repression of adipocyte genes or FoxO1.

Resveratrol exerts anti-obesity effects in high-fat diet obese mice and displays differential dosage effects on cytotoxicity, differentiation, and lipolysis in 3T3-L1 cells

“…Adipogenesis is known as a hyperplastic transformation from undifferentiated pre-adipocytes to mature adipocytes and, lipogenesis, the convert and accumulation of lipid droplets in adipocyte from free fatty acids. Regarding the anti-adipogenic effects, several studies have demonstrated that resveratrol inhibited adipogenesis at concentrations of 20 to 100 μM and in the treatment period length (24 hr to 8 days) [36][37][38][39]. Our results show that resveratrol attenuated adipogenesis and lipogenesis at concentrations of 1 to 10 μM which is much less than the above published studies.…”

“…Our study revealed distinct and much more dynamic actions of resveratrol on both high-fat diet obese mice and 3T3-L1 cells conferred by a wide range of concentrations, as compared to previous studies [35][36][37][38][39][40][41]. At low concentrations (below 10 μM), resveratrol appears to inhibit adipogenic differentiation and lipolysis.…”

β-catenin protein utilized by Tumour necrosis factor-α in porcine preadipocytes to suppress differentiation

“…Porcine preadipocytes were obtained as previously described (36,37). Cells were seeded in culture plates at a density of 5 × 10 4 cells/cm 2 and cultured at 37 o C in a humidified atmosphere containing 5% CO2.…”

“…The cellular lipid contents were determined with Oil red O (Sigma, USA) and the TG contents were determined with Oil red O extraction by the method of Liang Bai et al (36). Cellular morphology was examined and photographed with a light microscope.…”

Polymorphisms in the SIRT5 gene and their association with body measurement and ultrasound traits in Qinchuan cattle

“…A number of research studies have suggested that the SIRT1 and SIRT2 genes enhance proliferation of preadipocytes and inhibit preadipocyte apoptosis through their acetylation/deacetylation functions (Bai et al, 2007;Wang and Tong, 2009). Similarly, recent studies have suggested that SIRT5 has a similar function in humans (Nakagawa, 2009), but its mechanism of action remains unclear.…”