This study was to investigate the hypoglycemic effect of wogonoside to improve hepatic insulin resistance( IR) and its relative anti-inflammatory mechanism. The stable IR-Hep G2 cell model was established by the combination of 1×10-9 mol·L-1 insulin and 3. 75×10-6 mol·L-1 dexamethasone for 48 hours. The changes of glucose consumption in IR-Hep G2 cells with different concentrations of wogonoside( 1,5,10,20,50 μmol·L-1) at different time points( 30,36,48,54 h) were detected by glucose oxidase assay to determine the optimal onset time. Glycogen content and cell viability were respectively detected by ketone method and CCK-8 method. Cryptothermal protein 3( NLRP3),suppressor of cytokine signaling 3( SOCS3),Toll-like receptor 4( TLR4),nuclear factor( NF-κB),interleukin( IL-1β),IL-6,tumor necrosis factor( TNF-α) involving in the inflammatory signaling pathway,as well as leptin,Ob-R,p-IRS2/IRS2,p-PI3 K/PI3 K( p85),p-Akt/Akt and glucose transporter( GLUT1/2/4) involving in the insulin signaling pathway were detected in IR-HepG2 cells by Western blot. RESULTS: showed that 20 and 50 μmol·L-1 wogonoside significantly up-regulated the glucose consumption of IR-HepG2 cells( P<0. 001) as compared with IR model group,and the optimal onset time was 48 h.Wogonoside had no obvious effect on the cell viability of Hep G2 cells. Further studies showed that 20,50 μmol·L-1 wogonoside respectively increased the glycogen content of IR-HepG2 cells after 48 h treatment,especially in 50 μmol·L-1 group( P<0. 001). Compared with IR model group,wogonoside not only inhibited the protein expression of inflammatory nuclear transcriptional factors NLRP3,SOCS3,TLR4,NF-κB,but also decreased the expression of downstream inflammatory effect factors IL-1β,IL-6 and TNF-α． In addition,wogonoside elevated Ob-R,p-IRS2/IRS2,p-PI3 K/PI3 K( p85),p-Akt/Akt and GLUT1/2/4 protein expression,whereas it suppressed leptin expression that was regulated by SOCS3. Wogonoside could promote glucose uptake and increase glycogen content to enhance insulin sensitivity in IR-Hep G2 cells. The hypoglycemic effect may be related to the intervention of NLRP3/SOCS3-TLR4-NF-κB inflammatory pathway and decrease of inflammatory factor expression.

BACKGROUND: Royal jelly (RJ) has been used traditionally for dietary, cosmetic and health purposes for a long time in different parts of the world. Scientific studies have also shown its numerous health-promoting properties including hypoglycemic and anti-hypercholesterolemic action. In this study, we investigated the anti-adipogenic activity of RJ in 3 T3-L1 cells and isolated the major responsible root component for the activity.
METHODS: An active anti-adipogenic compound was isolated through bioassay-guided isolation process by successive treatment of RJ and its active fractions on 3 T3-L1 cell line. (E)-10-Hydroxy-2-decenoic Acid (10-HDA) was identified using NMR spectroscopy and ultra-performance liquid chromatography (UPLC). As 10-HDA showed significant anti-adipogenic activity with Oil Red O staining and TG content assay on 3 T3-L1 adipocytes, further study was carried out in molecular level for the expression of adipogenic transcription factors such as PPARγ, FABP4, C/EBPα, SREBP-1c, and Leptin. The effect of 10-HDA on preliminary molecules such as pAkt, pERK, C/EBPβ, and pCREB were studied in the early stage of adipogenesis. The effect of 10-HDA on reactive oxygen species (ROS) production in fully differentiating adipocytes was measured by nitro blue tetrazolium (NBT) assay.
RESULTS: Results showed that triacylglycerol accumulation and ROS production was markedly suppressed by 10-HDA. Preliminary molecules such as pAkt, pERK, pCERB, and C/EBPβ were found to be down-regulated by 10-HDA, which led to down-regulation of key adipogenic transcription factors such as PPARγ, FABP4, CEBPα, SREBP-1c, and Leptin on 3 T3-L1 adipocytes.
CONCLUSIONS: Our results suggest that anti-adipogenesis of 10-HDA on 3 T3-L1 adipocyte takes place via two mechanisms: inhibition of cAMP/PKA pathway and inhibition of p-Akt and MAPK dependent insulin signaling pathway. So it is considered that 10-HDA, a major component of RJ, can be a potential therapeutic medicine for obesity.

Growth rate is one of the most important traits from the point of view of individual fitness and commercial production in mollusks, but its molecular and physiological basis is poorly known. We have studied differential gene expression related to differences in growth rate in adult individuals of the commercial marine clam Ruditapes decussatus. Gene expression in the gills and the digestive gland was analyzed in 5 fast-growing and five slow-growing animals by means of an oligonucleotide microarray containing 14,003 probes. A total of 356 differentially expressed genes (DEG) were found. We tested the hypothesis that differential expression might be concentrated at the growth control gene core (GCGC), i.e., the set of genes that underlie the molecular mechanisms of genetic control of tissue and organ growth and body size, as demonstrated in model organisms. The GCGC includes the genes coding for enzymes of the insulin/insulin-like growth factor signaling pathway (IIS), enzymes of four additional signaling pathways (Raf/Ras/Mapk, Jnk, TOR, and Hippo), and transcription factors acting at the end of those pathways. Only two out of 97 GCGC genes present in the microarray showed differential expression, indicating a very little contribution of GCGC genes to growth-related differential gene expression. Forty eight DEGs were shared by both organs, with gene ontology (GO) annotations corresponding to transcription regulation, RNA splicing, sugar metabolism, protein catabolism, immunity, defense against pathogens, and fatty acid biosynthesis. GO term enrichment tests indicated that genes related to growth regulation, development and morphogenesis, extracellular matrix proteins, and proteolysis were overrepresented in the gills. In the digestive gland overrepresented GO terms referred to gene expression control through chromatin rearrangement, RAS-related small GTPases, glucolysis, and energy metabolism. These analyses suggest a relevant role of, among others, some genes related to the IIS, such as the ParaHox gene Xlox, CCAR and the CCN family of secreted proteins, in the regulation of growth in bivalves.