Solvothermal Synthesis of Novel Magnetic Nickel Based Iron Oxide Nanocomposites for Selective Capture of Global- and Mono-Phosphopeptides.

A facile solvothermal method was developed for synthesis of magnetic nickel-based iron oxide nanocomposites (MNFOs) with different ratios of Ni2+ to Fe3+ for different reaction time. Two factors including dosage of Ni source and length of reaction were investigated for influence on the morphology and composition of MNFOs, as well as their distinct selectivity for different phosphopeptides. After thorough characterization, the possible formation mechanism of MNFOs was proposed. Very interestingly, MNFOs with Ni2+/Fe3+ ratios of 4:5 prepared for 8 h (MNFO-S) and for 24 h (MNFO-L) can selectively capture global- and monophosphopeptides at the fmol level with excellent enrichment performance. These two affinity probes have been exploited to isolate and enrich the phosphopeptides from human normal hepatic cells HL 7702 after exposure to atmospheric fine particulates (PM2.1), which revealed that the protein phosphorylation level was increased significantly in cells after stimulation by fine particulate matters. The findings could provide a new insight for the nickel-based affinity protocol to analyze the mutation of phosphopeptides during cellular signaling pathways in response to exogenous environment stimulation. Consequently, this present work proposed a promising strategy to isolate monophosphopeptides from global phosphopeptides for phosphoproteome research.

[Research progress on therapeutic targets of active components in Chinese herbs for treatment of nonalcoholic fatty liver disease].

Nonalcoholic fatty liver disease(NAFLD) is a kind of metabolic liver injury, which is closely associated with insulin resistance and genetic susceptibility. Traditional Chinese herbs used in the treatment of nonalcoholic fatty liver disease are widely investigated in recent years. A series of recent studies show that the effects of the active components in traditional Chinese herbs on NAFLD are associated with activating AMPK signaling pathway, improving insulin resistance, modulating the activity and expression of peroxisome proliferator-activated receptor γ, antioxidant and anti-inflammatory activities and regulating intestinal flora. In this review, the potential therapeutic targets of the active components from traditional Chinese herbs for NAFLD would be summarized to provide a new thought for further research and clinical treatment of nonalcoholic fatty liver disease.

[Ginsenoside Rb1 upregulates expressions of GLUTs to promote glucose consumption in adiopcytes].

Previous studies have shown that ginsenoside Rb1 (Rb1), one of active components in ginseng, can activate insulin signaling pathway and promote translocation of glucose transporters (GLUTs) to increase glucose uptake in adipocytes. However, the effect of Rb1 on the expressions of GLUTs remains unknown. In this study, the effects of Rb1 on GLUT1 and GLUT4 were observed in 3T3-L1 adipocytes and epididymal adipose tissue of db/db obese diabetic mice. Male db/db mice were treated with Rb1 by intraperitoneal injection at the dosage of 20 mg x kg(-1) for 14 d. Rb1 reduced HOMA-IR significantly (P < 0.05, n = 5), and FBG and FINS sowed declining trend after treatment with Rb1. Rb1 recovered the expressions of GLUT1 and GLUT4 and phosphorylation of AKT in adipose tissue of db/db mice. In vitro, glucose consumption in 3T3-L1 adipocytes treated with 10 micromol x L(-1) Rb1 for 24 h was elevated (P < 0.05, n=3), and mRNA of GLUT1 and GLUT4 were up-regulated (P < 0.05, n=3) and proteins of GLUT1 and GLUT4 were also increased. AKT was activated in adipocytes treated with Rb1 for 3 h. It can be concluded that ginsenoside Rb1 can up-regulate the expression of GLUTs in adipose tissue, in addition to activate insulin signalling pathway, which may partially account for its insulin sensitizing activity and regulating effect of glucose metabolism.

Rhein targets macrophage SIRT2 to promote adipose tissue thermogenesis in obesity in mice.

Rhein, a component derived from rhubarb, has been proven to possess anti-inflammatory properties. Here, we show that rhein mitigates obesity by promoting adipose tissue thermogenesis in diet-induced obese mice. We construct a macrophage-adipocyte co-culture system and demonstrate that rhein promotes adipocyte thermogenesis through inhibiting NLRP3 inflammasome activation in macrophages. Moreover, clues from acetylome analysis identify SIRT2 as a potential drug target of rhein. We further verify that rhein directly interacts with SIRT2 and inhibits NLRP3 inflammasome activation in a SIRT2-dependent way. Myeloid knockdown of SIRT2 abrogates adipose tissue thermogenesis and metabolic benefits in obese mice induced by rhein. Together, our findings elucidate that rhein inhibits NLRP3 inflammasome activation in macrophages by regulating SIRT2, and thus promotes white adipose tissue thermogenesis during obesity. These findings uncover the molecular mechanism underlying the anti-inflammatory and anti-obesity effects of rhein, and suggest that rhein may become a potential drug for treating obesity.

[Effect of ginsenoside Rb1 in ameliorating insulin resistance and ectopic fat deposition in obese mice induced by high fat diet].

Ginsenoside Rb1 is an active component in ginseng. Previous in vitro experiments showed that ginsenoside Rb1, could inhibit lipolysis and promote glucose transporter in adipocytes. This study focused on the effect of ginsenoside Rb1 in insulin resistance and ectopic fat deposit in obese mice induced by high fat diet and its molecular mechanism. Obese male C57/L mice induced by high fat diet were randomly divided into the diet-induced obesity group (DIO group), the ginsenoside Rb1 group (Rb1 group) and the rosiglitazone group (Rog group), and continuously fed with high fat diet. In addition, male C57/L mice fed with normal diet were selected as the normal group (NC group). Mice in Rb1 group and Rog groups were intraperitoneally injected with ginsenoside Rb1 and rosiglitazone with the dosage of 20 mg x kg(-1) and 10 mg x kg(-1), respectively. NC and DIO groups were intraperitoneally injected with the same amount of saline. Two weeks later, the intraperitoneal glucose tolerance test (IPGTT) was performed. Three days later, the mice were killed, and their serum samples were collected to detect insulin and free fatty acid (FFA). Their livers were weighed to examine the triglyceride content, and a pathological detection was performed. Epididymal adipose tissues were weighed, and PDE3B, HSL and perilipin were detected by Western blotting. The results showed that the treatment with ginsenoside Rb1 for two weeks could improve the glucose tolerance of obese mice. Except for 0-120 min, the areas under the glucose tolerance curve (0-30 min, 0-60 min and 0-90 min) in the Rb1 group were less than that in the DIO group (P < 0.05, n = 5), with a much lower HOMA-IR (P < 0.05, n = 5). The fat level of obese mice was significantly reduced by Rbl (P < 0.05, n = 5), and so were liver weight/weight (P < 0.05, n = 8). The increased serum FFA of obese mice declined after the treatment of Rb1 (P < 0.05, n = 8). Rb1 could partially recover the expression of perilipin in adipose tissues, but without obvious change in the expressions of PDE3B and HSL and the phosphorylated activation. The above findings indicated that ginsenoside Rb1 could reduce the release of FFA and alleviate the ectopic deposit of triglyceride by up-regulating the expression of perilipin in adipose tissue, which may be one of its mechanisms for improving the insulin resistance and abnormal glucose metabolism of organisms.

Atractylodin Induces Myosin Light Chain Phosphorylation and Promotes Gastric Emptying through Ghrelin Receptor.

Atractylodin is one of the main constituents in the rhizomes of Atractylodes lancea Thunb., being capable of treating cancer cachexia-anorexia and age-related diseases as an agonist of growth hormone secretagogue receptor (GHSR). GHSR was herein expressed in human gastric smooth muscle cells (HGSMCs) and activated by ghrelin receptor agonist L-692,585. Like L-692,585, atractylodin also increased Ca2+ and enhanced the phosphorylation of myosin light chain (MLC) through GHSR in HGSMCs. In addition, atractylodin promoted gastric emptying and MLC phosphorylation in the gastric antrum of mice also through GHSR. Collectively, atractylodin can activate GHSR in gastric smooth muscle, as a potential target in clinical practice.

Potent therapeutic effects of shouwu jiangqi decoction on polycystic ovary syndrome with insulin resistance in rats.

OBJECTIVE: To investigate the effect of Shouwu Jiangqi Decoction (SJD) on polycystic ovary syndrome (PCOS) with insulin resistance (IR) in rats and to explore the underlining molecular mechanisms. METHODS: A total of 51 female Sprague-Dawley rats were randomly divided into 6 groups: control group (n=7), model group (n=8), SJD high-dose group (n=9), SJD medium-dose group (n=9), SJD low-dose group (n=9) and DMBG group (n=9). Radioimmunoassay was used to measure serum follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone concentrations and qRT-PCR and western blot were used to examine the expression levels of mRNA and protein respectively of insulin receptor substrate 1 (IRS-1) and phosphatidylinositide 3-kinases (PI3K) p85α in different groups. RESULTS: FSH level significantly decreased in the model group compared with the normal control (P<0.01), and high-dose SJD and DMBG can significantly increase FSH level (P<0.01). LH level showed a mild increase without statistic significance in the model group compared with the control and different dosages of SJD had no significance effect on LH level, while DMBG can significantly decrease LH level (P<0.01). Testosterone level significantly increased in the model group compared with the control group (P<0.01), and high-dose SJD and DMBG can significantly decrease testosterone level (P<0.01). The expression of IRS-1 as well as PI3Kp85α were significantly decreased in the model group compared with the normal control group at both mRNA (P<0.001) and protein (P<0.01) level, and both high-dose SJD and DMBG can enhance IRS-1 and PI3K expression (P<0.05). CONCLUSIONS: SJD has potent therapeutic effects on PCOS with IR in rats. The therapeutic effects of SJD on IR and ovulatory dysfunction are probably achieved through correcting the defective insulin signaling transduction.