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Two series of tetrahydrocarbazole derivatives have been designed and synthesized based on ZG02, a promising candidate developed in our previous studies. The newly prepared compounds were screened for glucose consumption activity in HepG2 cell lines. Aza-tetrahydrocarbazole compound 12b showed the most potent hypoglycemic activity with a 45% increase in glucose consumption when compared to the solvent control, which had approximately 1.2-fold higher activity than the positive control compounds (metformin and ZG02). An investigation of the potential mechanism indicated that 12b may exhibit hypoglycemic activity via activation of the AMPK pathway. Metabolic stability assays revealed that 12b showed good stability profiles in both artificial gastrointestinal fluids and blood plasma from SD rats. An oral glucose tolerance test (OGTT) was performed and the results further confirmed that 12b was a potent hypoglycemic agent.

Background and Purpose Glucagon-like peptide-1 (GLP-1) is an important target for diabetes therapy based on its key role in maintaining glucose and lipid homeostasis. This study was designed to investigate antidiabetic and hepatoprotective effects of novel oleanolic acid derivative DKS26 in diabetic mice and elucidate its underlying GLP-1 related antidiabetic mechanisms in vitro and in vivo. Experimental Approach The therapeutic effects of DKS26 were inspected in streptozotocin (STZ)-induced and db/db diabetic mouse models including levels of plasma glucose, glycosylated serum protein (GSP), lipid profiles, insulin, alanine aminotransferase (ALT) and aspartate aminotransferase (AST), oral glucose tolerance (OGT), pancreatic islets and hepatic histopathological morphology, liver lipid levels and expression of pro-inflammation cytokines. The intestinal NCI-H716 cells and diabetic models were used to further validate its potential GLP-1 related antidiabetic mechanisms. Key Results Decreased levels of plasma glucose, GSP, ALT and AST, ameliorated OGT and plasma lipid profiles, augmented plasma insulin levels, alleviated islets and hepatic pathological morphology, and reduced liver lipid, inflammation and necrosis accumulation were observed after DKS26 treatment at a dose of 100 mg·kg-1·day-1 in vivo. Furthermore, DKS26 enhanced GLP-1 release and expression, accompanied by elevated levels of cAMP and phosphorylated PKA in vitro and in vivo. Conclusion and Implications DKS26 exerted hypoglycemic, hypolipidemic and islets protective effects, which was associated with promoted GLP-1 release and expression mediated by the activated cAMP/PKA signaling pathway, and mitigated hepatic damage through the reduction of liver lipid and inflammation. These findings firmly identified DKS26 as a new viable therapeutic option for diabetes control.

Accumulating clinical evidence indicates that diabetic liver cancer patients are less sensitive to intra-arterial chemotherapy than non-diabetic cancer patients. However, the underlying mechanism remains largely uncharacterized. Here, we report that hyperglycemia inhibits AMPK pathway and subsequently reduces adriamycin (ADR)-induced DNA damage, resulting in decreased chemotherapeutic sensitivity of ADR. HepG2 and Bel-7402 cells were treated with ADR in various glucose conditions and then subjected to cell proliferation assay and apoptosis. The IC50of ADR greatly increased with the increasing concentration of glucose (15 ± 4 nM to 93 ± 39 nM in HepG2, 78 ± 8 nM to 1310 ± 155 nM in Bel-7402). Both FACs and Western blot analysis indicated that high concentration of glucose protected cells from ADR-induced apoptosis. Mouse hepatoma H22 xenografts were established both in db/db diabetic mice and STZ-induced diabetic mice. The inhibitory effect in tumor growth of ADR was significantly reduced in diabetic mice, which could be recovered by insulin therapy. Hyperglycemia greatly ameliorated AMPK activation and H2AX expression caused by ADR treatment. Pretreatment with compound C or AMPK silencing eliminated hyperglycemia reduced cytotoxicity of ADR. However, the impaired cytotoxicity in hyperglycemia was recovered by treatment with AMPK activator AICAR. This study indicates that hyperglycemia impairs the chemotherapeutic sensitivity of ADR by downregulating AMPK pathway and reducing ADR-induced DNA damage.

Ethnopharmacological relevance The radix of Acorus calamus L. (AC) is widely used in diabetes therapies in traditional folk medicine from America and Indonesia, and we have previously reported that the ethyl acetate fraction of AC (ACE) acts as an antidiabetic through insulin sensitizing, insulin releasing and alpha-glucosidase inhibitory activities. The present study is designed to investigate the effects and molecular mechanisms of ACE on glucagon-like peptide-1 (GLP-1) expression and secretion related to its hypoglycemic effects. Materials and methods The hypoglycemic effect of ACE (100 mg/kg, i.g.) was confirmed by testing blood glucose levels or via oral glucose tolerance test (OGTT) in streptozotocin (STZ) induced hyperglycemic mice, db/db diabetic mice and diet-induced obese (DIO) mice. Plasma insulin, GLP-1 levels and intestinal GLP-1 related gene expression were determined in STZ-induced and db/db diabetic mice. The in vitro effects of ACE (12.5 μg/ml) on the expression and secretion of GLP-1 were detected in NCI-H716 intestinal L-cells, and the correlation between ACE and molecules in the Wnt signaling pathway was further explored. Results ACE (100 mg/kg) significantly lowered fasting blood glucose in STZ-induced and db/db diabetic mice and improved the OGTT in DIO mice. Insulin releasing and islet protective effects, along with the increased secretion of GLP-1, were observed. The expression of proglucagon gene ( gcg ) and post-translational processing gene prohormone convertase 3 ( pc3 ) and the GLP-1 content in the culture medium of L-cells notably increased after the ACE treatment (12.5 μg/ml). At the same time, β-catenin nuclear translocation occurred, and its downstream protein cyclin D1 was activated, showing the involvement of Wnt signaling. Conclusions ACE might activate Wnt signaling to increase the gene expression of gcg and pc3 and exert incretin effects, including insulinotropic and islet protection, to lower blood glucose levels via elevated GLP-1 secretion either directly or indirectly.

A series of tetrahydrocarbazole derivatives was designed and synthesized on the basis of the AMP-activated protein kinase activator GY3. All the synthesized compounds were screened in HepG2 cell lines for glucose consumption activity and several of them showed potent glucose decreasing activity. In vivo evaluation of the hypoglycemic and hypolipemic effects indicated that 7a exhibited comparable activity with pioglitazone, but with a weaker body-weight increasing effect. The pharmacokinetic profiles of 7a were also investigated.

Thirty four terpenoids, including two new cadinane-type sesquiterpenoids containing conjugated aromatic-ketone moieties, curcujinone A (1) and curcujinone B (2), were isolated from 95% ethanol extract of the root tubers of Curcuma wenyujin. Their structures were determined by spectroscopic methods, especially 2D NMR and HRMS techniques. The relative and absolute configurations of 1 and 2 were identified by quantum chemical DFT and TDDFT calculations of the 13C NMR chemical shifts, ECD spectra, and specific optical rotations. All compounds and extracts were evaluated for their anti-diabetic activities with a glucose consumption model on HepG2 Cells. The petroleum fraction CWP (10μg/mL) and compounds curcumenol (4), 7α,11α-epoxy-5β-hydroxy-9-guaiaen-8-one (5), curdione (17), (1S, 4S, 5S 10S)-germacrone (18), zederone (20), a mixture of curcumanolide A (25) and curcumanolide B (26), gajutsulactone B (27), and wenyujinin C (30) showed promising activities with over 45% increasing of glucose consumption at 10μM.

First, as the 4G network, the introduction of IPv6 network layer security mechanism, security is enhanced at the same time, IPv6 security mechanism applied to the 4G network system security as well as new demands and challenges, followed by the core network based on IPv6 network security to face the next 4G threats and security problems, concludes with IPv6 technical analysis and 4G network defense and countermeasures.

The purpose of this study is to prove the lipid-regulating effects of neohesperidin (NHP) and explore the potential mechanisms related to fibroblast growth factor 21 (FGF21) and AMP-activated protein kinase (AMPK). Free fatty acids (FFAs)-induced lipid-accumulated HepG2 cells, acutely egg yolk-induced dyslipidemia and chronically diet-induced obese (DIO) model mice were treated with NHP. Biochemical analyses were carried out to determine the lipid profiles. Western blotting and real-time PCR were employed to analyze FGF21, AMPK and the related proteins or mRNA expressions. Body weight and food intake were measured in DIO mice. siRNA or inhibitors of FGF21 or AMPK were utilized in further study. NHP showed potent hypolipidemic effect in HepG2 cells loaded with FFAs and reversed the pathological changes of lipid in the acute or chronic dyslipidemia mouse model. It obviously improved the lipid profiles in plasma, liver and gastrocnemius muscles in DIO mice, and led to a significant body weight loss. Simultaneously, FGF21 protein expression or secretion, and AMPK/sirtuin type 1 (SIRT1)/peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) axis or related molecules, was improved by NHP in HepG2 cells and/or DIO mice. Furthermore, the siRNA or inhibitor targeting FGF21 or AMPK rejected the triglyceride-lowering effect of NHP. In conclusion, NHP regulates lipid metabolism in vivo and in vitro via FGF21 and AMPK/SIRT1/PGC-1α signaling axis.

A new sesquiterpenoid, 1 β ,5 α -guaiane-4 β ,10 α -diol-6-one ( 1 ), was isolated from 70% EtOH extract of the rhizomes of Acorus calamus . The structure was determined on spectroscopic methods, especially 2D NMR techniques. The absolute configuration of 1 was confirmed by TDDFT quantum chemical calculation of its ECD spectrum. Compound 1 showed promising anti-diabetic activity on a insulin-mediated glucose consumption model of HepG2 cells.

This article first has carried on the brief elaboration to the 4G mobile communication system's network architecture and the key technologies, will face more and more threats facing future 4G mobile communication network security, has analyzed the communication network, the 4G network safety mechanism and 4G the correspondence development faced with the security threat question, next will adopt the mobile communication network security the protection technology, finally proposed in the future must study question and development direction.

Acorus calamus L. (AC), family Araceae, have been used in the Indian and Chinese systems of medicine for hundreds of years. The radix of AC is widely used in the therapy of diabetes in traditional folk medicine of America and Indonesia. Aim of the study To investigate the insulin sensitizing activity and antidiabetic effects of the ethyl acetate fraction of AC (ACE). Materials and methods Glucose consumption mediated by insulin was detected in L6 rat skeletal muscle cells. Diabetes and its complications related indexes were monitored after orally administrating to genetically obese diabetic C57BL/Ks db/db mice daily for 3 weeks. Results ACE (12.5 and 25 μg/ml) increased glucose consumption mediated by insulin in L6 cells (p

Obesity is known to be the primary causal component in metabolic syndrome. Adipocytes in obese patients exhibit increased oxidative stress via the activation of reactive oxygen species (ROS)-producing systems and inactivation of antioxidant enzymes. Extracellular superoxide dismutase (EC-SOD) is an anti-inflammatory enzyme that protects cells from the damaging effects of ROS. An earlier report showed that plasma EC-SOD levels in type 2 diabetic patients were significantly and inversely related to body mass index and homeostasis model assessment-insulin resistance index. Moreover, the administration of pioglitazone, an antidiabetic agent, significantly increased the plasma level of EC-SOD. In this report, the expression of EC-SOD was compared to other adipocytokines in mice 3T3-L1 pre-adipocytes. EC-SOD expression levels were increased after the induction of differentiation and then declined, which was similar to adiponectin and transcription factors such as peroxisome proliferator-activated receptor-gamma (PPAR-gamma) and CCAAT/enhancer-binding protein-alpha (C/EBP-alpha). On the other hand, the expression levels of pro-inflammatory adipocytokines, such as tumor necrosis factor-alpha (TNF-alpha) and monocyte chemo-attractant protein-1 (MCP-1), increased markedly in the development stage of cells. It was observed that the expression of EC-SOD in differentiated 3T3-L1 cells co-cultured with LPS-stimulated J774 macrophages was up-regulated, while the addition of TNF-alpha down-regulated EC-SOD and adiponectin expression in adipocytes. It is known that infiltrated and activated macrophages produce extracellular ROS at high levels in adipose tissue. It is possible that the expression of EC-SOD in adipocytes was stimulated to protect them from oxidative stress in the co-culture system.

To examine the insulin sensitizing effects of a novel α-methyl-α-phenoxylpropionate derivative YY20 in insulin-sensitive cell lines. The peroxisome proliferator-activated receptor γ (PPARγ) agonist bioactivities of YY20 were detected by a preadipocyte differentiation assay. RT-PCR and Western blotting analysis were used to detect the expression of the target gene or protein. The effects of YY20 on insulin-mediated glucose consumption were determined in the HepG2 human hepatocellular carcinoma line. YY20 could enhance the differentiation of preadipocytes to adipocytes and upregulate the gene expression of PPARγ2, as well as the protein expression of insulin receptor sub-strate-1 (IRS-1), glucose transporter-4 (GLUT4), and adiponectin (ACRP30). The effects on GLUT4 and ACRP30 could be reversed by the PPARγ inhibitor SR-202. Furthermore, YY20 efficiently reduced glucose consumptions in HepG2 cells after 24 h culture, and the effects were related to insulin and YY20 concentrations. YY20, a potential insulin-sensitizing agent like rosiglitazone, could enhance glucose consumption in HepG2 cells in a concentration- and insulin-dependent manner. It may improve the insulin resistance associated with type 2 diabetes.

The AMP-activated protein kinase (AMPK) is a ubiquitously expressed serine/threonine protein kinase that functions as an intracellular fuel sensor. It has been demonstrated to mediate the activities of a number of pharmacological and physiological factors that exert beneficial effects on type2 diabetes mellitus. GY3 is a novel synthesized indole compound derived from indomethacin, a non-steroid anti-inflammatory drug. In a previous study, we found that GY3 could improve insulin resistance and lower glucose levels in db/db mice, although its mechanism of action is not yet clear. In this study, we demonstrate that in vivo administration of GY3 improved serum triglyceride levels and decreased lipid accumulation in the livers of db/db mice. In vitro studies show that GY3 increased glucose consumption in HepG2 cells and 3T3-L1 adipocytes, decreased free fatty acid (FFA)-induced lipid accumulation in HepG2 cells and lipid accumulation in 3T3-L1 adipocytes. In vitro studies further show that GY3 improved glucose and lipid metabolism through an AMPK-dependent pathway but not the PI3K pathway. These findings suggest that GY3 is an effective agent for the improvement of glucose and lipid metabolism through AMPK pathway activation.

Ethnopharmacological relevance The radix of Acorus calamus L. (AC) is widely used in the therapy of diabetes in traditional folk medicine of America and Indonesia, and we previously reported the insulin sensitizing activity of the ethyl acetate fraction of AC (ACE). Aim of the study To investigate the insulin releasing and alpha-glucosidase inhibitory activity of ACE in vitro and in vivo . Materials and methods Insulin releasing and alpha-glucosidase inhibitory effects of different fractions from AC were detected in vitro using HIT-T15 cell line and alpha-glucosidase enzyme. Furthermore, effects of ACE orally on serum glucose were detected in fasted and glucose/amylum challenged normal mice. Results AC and ACE increased insulin secretion in HIT-T15 cells as gliclazide did. As in vivo results, ACE (400 and 800 mg/kg) significantly decreased fasting serum glucose, and suppressed the increase of blood glucose levels after 2 g/kg glucose loading in normal mice. In addition, ACE as a mixed-type inhibitor inhibited alpha-glucosidase activity in vitro with an IC 50 of 0.41 μg/ml, and 100 mg/kg of it clearly reduced the increase of blood glucose levels after 5 g/kg amylum loading in normal mice. Conclusions Apart from its insulin sensitizing effect, ACE may have hypoglycemic effects via mechanisms of insulin releasing and alpha-glucosidase inhibition, and thus improves postprandial hyperglycemia and cardiovascular complications.

A series of phenylalanine derivatives were synthesized and their biological activities were evaluated. Compounds (S)-3 and (R)-3 exhibited more potent insulin-releasing activity than that of nateglinide, compound (S)-3 also showed insulin-sensitizing activity in vitro. Both compounds were tested for hypoglycemia effect in vivo.

A series of phenylalanine derivatives were synthesized and their biological activities were evaluated. Compounds (S)-3 and (R)-3 exhibited more potent insulin-releasing activity than that of nateglinide, compound (S)-3 also showed insulin-sensitizing activity in vitro. Both compounds were tested for hypoglycemia effect in vivo.

The effects of fractions partitioned from the ethanol extract of Acorus calamus L. (AC) on adipocyte differentiation were investigated using cultured mouse 3T3-L1 preadipocytes. The degree of differentiation was evaluated by measuring the cellular triglycerides and protein expression of the glucose transporter GLUT4 in 3T3-L1 cells. The ethyl acetate fraction of the AC extract (ACE) was found to enhance adipocyte differentiation as did rosiglitazone. The results of further fractionation of ACE indicated that the active fraction does not consist of beta-asarone, which is a toxic component of this plant. This finding suggests that ACE has potential insulin-sensitizing activity like rosiglitazone, and may improve type 2 diabetes.

To examine the insulin sensitizing effects of a novel alpha-methyl-alpha- phenoxylpropionate derivative YY20 in insulin-sensitive cell lines.The peroxisome proliferator-activated receptor gamma (PPAR gamma) agonist bioactivities of YY20 were detected by a preadipocyte differentiation assay. RT-PCR and Western blotting analysis were used to detect the expression of the target gene or protein. The effects of YY20 on insulin-mediated glucose consumption were determined in the HepG2 human hepatocellular carcinoma line.YY20 could enhance the differentiation of preadipocytes to adipocytes and upregulate the gene expression of PPAR gamma 2, as well as the protein expression of insulin receptor substrate- 1 (IRS-1), glucose transporter-4 (GLUT4), and adiponectin (ACRP30). The effects on GLUT4 and ACRP30 could be reversed by the PPAR gamma inhibitor SR-202. Furthermore, YY20 efficiently reduced glucose consumptions in HepG2 cells after 24 h culture, and the effects were related to insulin and YY20 concentrations.YY20, a potential insulin-sensitizing agent like rosiglitazone, could enhance glucose consumption in HepG2 cells in a concentration- and insulindependent manner. It may improve the insulin resistance associated with type 2 diabetes.

Thiazolidinediones (TZDs) such as rosiglitazone are antidiabetic peroxisome proliferator-activated receptor gamma (PPARgamma) agonists. PPARgamma agents improve diabetes by increasing insulin sensitivity and enhancing the differentiation of preadipocytes into adipocytes. The present study aimed to identify if 1-(4-chlorobenzoyl)-5-hydroxy-2-methyl-3-indoleacetitic acid (GY3), a newly synthesized indole compound, could enhance adipocytes differentiation and insulin sensitivity. The results showed that both GY3 and rosiglitazone significantly increased the lipid accumulating of 3T3-L1 adipocytes induced by isobutylmethylxanthine, dexamethasone and insulin mixture, but GY3 (not rosiglitazone) failed to increase the lipid accumulation when induced by insulin alone. In addition, GY3- or rosiglitaozne-induced protein expression of GLUT4 and adiponectin was determined by Western blot analysis. GY3 activated PPARalpha weakly but did not affect PPARgamma, while rosiglitazone activated PPARgamma significantly, suggesting different mechanisms between GY3 and rosiglitazone on adipocyte differentiation. Furthermore, both GY3 and rosiglitazone enhanced the adiponectin and insulin pathway proteins expression and adiponectin secretion in mature adipocytes, but only GY3 not rosiglitazone elevated gene expression of leptin and resistin. Both GY3 and rosiglitazone enhanced glucose consumption in HepG2 cells especially in the presence of insulin. In the in vivo study, GY3 decreased serum glucose and insulin in db/db mice, indicating the insulin sensitizing effect might contribute to its antidiabetic mechanism. Altogether, these results suggest that GY3 could improve insulin resistance and lower glucose level, GY3 and its derivatives might be developed as a substitution therapy for diseases with insulin resistance.

To study the anti-hyperglycemic effect and its mechanism of Dendrobium candidum (DC).Normal mice, adrenaline-induced hyperglycemic mice, streptozotocin-induced diabetic (STZ-DM) rats were used. The mechanisms of the anti-hyperglycemic action were studied with radio-immunoassay, immunohistochemical HRP-SPA stain, etc.DC could not obviously decrease the serum glucose concentrations and insulin levels in normal mice. It could increase serum insulin levels and decrease serum glucagons concentrations in STZ-DM rats. The results of immunohistochemical stain demonstrated that the number of islet beta cells was increased and that of islet a cells was decreased in STZ-DM rats. It could also decrease the serum glucose concentrations and increase liver glucogen contents in adrenaline-induced hyperglycemic mice.DC has obvious anti-hyperglycemic effects in adrenaline-induced hyperglycemic mice and STZ-DM rats. Its mechanisms are stimulating the secretion of insulin from beta cells and inhibiting the secretion of glucagons from a cells, and it can probably decrease the decomposition of liver glucogen and increase the synthesis of liver glucogen.