Cirsimarin, a potent antilipogenic flavonoid, decreases fat deposition in mice intra-abdominal adipose tissue

International audienceOBJECTIVE: We previously reported that the flavonoid cirsimarin exerts in vitro a strong lipolytic activity on isolated adipocytes. This study was therefore designed to evaluate in vivo the effects of cirsimarin on white adipose tissue (WAT) accretion in mice. METHODS: Male CD1 mice were injected daily with either vehicle (intraperitoneal (i.p.)) or cirsimarin (25 or 50 mg kg(-1) per day, i.p.) for 18 days. Mice were killed and fat pads weighted. Epididymal fat pads were used for cellularity measurement. Effects of cirsimarin treatment on lipolysis and lipogenesis in WAT were assessed. RESULTS: Mice treated with 25 or 50 mg kg(-1) per day cirsimarin showed a decrease in retroperitoneal (-29 and -37% respectively, P<0.005) and epididymal (-25 and -28% respectively, P<0.005) fat pad weights compared with controls. This effect was restricted to intra-abdominal WAT as no difference was noticed for subcutaneous inguinal WAT. The decrease in intra-abdominal WAT accretion was due to a decrease in adipose cell diameter (-5 and -8% for 25 and 50 mg kg(-1) per day cirsimarin, respectively) resulting in a 14 and 35% decrease in adipose cell volume while no change was noticed in total adipocyte number. Direct injection of cirsimarin (50 mg kg(-1)) to rats did not trigger lipolysis. In contrast, cirsimarin showed in vivo as well as in vitro a strong antilipogenic activity, which may be the critical aspect of its effects on fat accretion in mice. The inhibitory concentration 50% of cirsimarin on lipogenic activity in isolated adipocytes was found to be 1.28$\pm$0.04 μM. Cirsimarin given orally reduced intra-abdominal fat accretion in mice. CONCLUSION: Cirsimarin exerts potent antilipogenic effect and decreases adipose tissue deposition in mice. Cirsimarin could therefore be a potential candidate for the treatment of obesity

Transcriptomic variation of hepatopancreas reveals the energy metabolism and biological processes associated with molting in Chinese mitten crab, Eriocheir sinensis

Molting is a critical developmental process for crustaceans, yet the underlying molecular mechanism is unknown. In this study, we used RNA-Seq to investigate transcriptomic profiles of the hepatopancreas and identified differentially expressed genes at four molting stages of Chinese mitten crab (Eriocheir sinensis). A total of 97,398 transcripts were assembled, with 31,900 transcripts annotated. Transcriptomic comparison revealed 1,189 genes differentially expressed amongst different molting stages. We observed a pattern associated with energy metabolism and physiological responses during a molting cycle. In specific, differentially expressed genes enriched in postmolt were linked to energy consumption whereas genes enriched in intermolt were related to carbohydrates, lipids metabolic and biosynthetic processes. In premolt, a preparation stage for upcoming molting and energy consumption, highly expressed genes were enriched in response to steroid hormone stimulus and immune system development. The expression profiles of twelve functional genes detected via RNA-Seq were corroborated through real-time RT-PCR assay. Together, our results, including assembled transcriptomes, annotated functional elements and enriched differentially expressed genes amongst different molting stages, provide novel insights into the functions of the hepatopancreas in energy metabolism and biological processes pertaining to molting in crustaceans