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Despite major investment by pharmaceutical companies in conventional drug discovery pipelines, development of new drugs has failed to keep up with the increasing incidence of many diseases, including type 2 diabetes (T2D). Drug repurposing, where existing drugs are applied to a new indication, is gaining momentum as a successful approach to overcome the bottlenecks commonly encountered with conventional approaches. Repurposing takes advantage of available information on the molecular pharmacology of clinical agents to drastically shorten drug development timelines. This review discusses recent advances in the discovery of new antidiabetic agents using repurposing strategies. [ABSTRACT FROM AUTHOR]

The present study investigated the role of dietary cholesterol and fat in the development of nonalcoholic fatty liver disease, a common liver disease in metabolic disorders. Mice were fed a diet of regular chow (CH), chow supplemented with 0.2% w/w cholesterol (CHC), high fat (HF, 45kcal%) or HF with cholesterol (HFC) for 17weeks. While both HF and HFC groups displayed hepatic steatosis and metabolic syndrome, only HFC group developed the phenotype of liver injury, as indicated by an increase in plasma level of alanine transaminase (ALT, by 50-80%). There were ~2-fold increases in mRNA expression of tumor necrosis factor α, interleukin 1β and monocyte chemotactic protein 1 in the liver of HFC-fed mice (vs. HF) but no endoplasmic reticulum stress or oxidative stress was observed. Furthermore, cholesterol suppressed HF-induced increase of peroxisome proliferator-activated receptor γ coactivator 1α and mitochondrial transcription factor A expression and blunted fatty acid oxidation. Interestingly, after switching HFC to HF diet for 5weeks, the increases in plasma ALT and liver inflammatory markers were abolished but the blunted of mitochondrial function remained. These findings suggest that cholesterol plays a critical role in the conversion of a simple fatty liver toward nonalcoholic steatohepatitis possibly by activation of inflammatory pathways together with retarded mitochondrial function. [ABSTRACT FROM AUTHOR]

Background and Purpose Matrine is a small molecule drug used in humans for the treatment of chronic viral infections and tumours in the liver with little adverse effects. The present study investigated its therapeutic efficacy for insulin resistance and hepatic steatosis in high-fat-fed mice. Experimental Approach C57BL/ J6 mice were fed a chow or high-fat diet for 10 weeks and then treated with matrine or metformin for 4 weeks. The effects on lipid metabolism and glucose tolerance were evaluated. Key Results Our results first showed that matrine reduced glucose intolerance and plasma insulin level, hepatic triglyceride content and adiposity in high-fat-fed mice without affecting caloric intake. This reduction in hepatosteatosis was attributed to suppressed lipid synthesis and increased fatty acid oxidation. In contrast to metformin, matrine neither suppressed mitochondrial respiration nor activated AMPK in the liver. A computational docking simulation revealed HSP90, a negative regulator of HSP72, as a potential binding target of matrine. Consistent with the simulation results, matrine, but not metformin, increased the hepatic protein level of HSP72 and this effect was inversely correlated with both liver triglyceride level and glucose intolerance. Conclusions and Implications Taken together, these results indicate that matrine may be used for the treatment of type 2 diabetes and hepatic steatosis, and the molecular action of this hepatoprotective drug involves the activation of HSP72 in the liver. [ABSTRACT FROM AUTHOR]

Hepatic steatosis is often associated with insulin resistance as a hallmark of the metabolic syndrome in the liver. The present study investigated the effects of PPARα activation induced by fenofibrate (FB) on the relationship of insulin resistance and hepatic steatosis in mice fed a high-fat (HF) diet, which increases lipid influx into the liver. Mice were fed HF diet to induce insulin resistance and hepatic steatosis with or without FB. FB activated PPARα and ameliorated HF diet-induced glucose intolerance and hepatic insulin resistance without altering either hepatic steatosis or inflammation signaling (JNK or IKK). Interestingly, FB treatment simultaneously increased fatty acid (FA) synthesis (50%) and oxidation (66%, both p < 0.01) into intermediate lipid metabolites, suggesting a FA oxidation-synthesis cycling in operation. Associated with these effects, diacylglycerols (DAGs) were sequestered within the lipid droplet/ER compartment, thus reducing their deposition in the cellular membrane, which is known to impair insulin signal transduction. These findings suggest that the reduction in membrane DAGs (rather than total hepatic steatosis) may be critical for the protection by fenofibrate-induced PPARα activation against hepatic insulin resistance induced by dietary fat. [ABSTRACT FROM AUTHOR]

Our recent study (referred as Study 1) showed that the triterpenoid oleanolic acid (OA) was able to produce a sustained correction of hyperglycemia beyond treatment period in type 2 diabetes (T2D) mice with liver as a responsible site. To follow up the previous observations, the present study (referred as Study 2) investigated the possible role of acetylation of FoxO1 and associated events in this therapeutic memory by characterizing the pathways regulating the acetylation status during and post-OA treatments. OA treatment (100 mg/kg/day for 4 weeks, during OA treatment) reduced hyperglycemia in T2D mice by ∼87% and this effect was largely (∼70%) maintained even 4 weeks after the cessation of OA administration (post-OA treatment). During OA treatment, the acetylation and phosphorylation of FoxO1 were markedly increased (1.5 to 2.5-fold) while G6Pase expression was suppressed by ∼80%. Consistent with this, OA treatment reversed pyruvate intolerance in high-fat fed mice. Histone acetyltransferase 1 (HAT1) content was increased (>50%) and histone deacetylases (HDACs) 4 and 5 (not HDAC1) were reduced by 30–50%. The OA-induced changes in FoxO1, G6Pase, HAT1 and HDACs persisted during the post-OA treatment period when the increased phosphorylation of AMPK, SIRT1 content and reduced liver triglyceride had subsided. These results confirmed the ability of OA to control hyperglycemia far beyond treatment period in T2D mice. Most importantly, in the present study we demonstrated acetylation of FoxO1 in the liver is involved in OA-induced memory for the control of hyperglycemia. Our novel findings suggest that acetylation of the key regulatory proteins of hepatic gluconeogenesis is a plausible mechanism by the triterpenoid to achieve a sustained glycemic control for T2D. [ABSTRACT FROM AUTHOR]

Purpose in life is critical to positive development among youth, especially those purposes that focus on an aspect of the world beyond the self. However, existing instruments have not adequately assessed beyond-the-self purpose. The Claremont Purpose Scale addresses the purpose construct, measuring the goal orientation, personal meaningfulness, and beyond-the-self focus among youth in the United States. We developed a version of the scale for use in the Chinese context among youth. In our two-part study, Study 1 developed the preliminary scale, and Study 2 evaluated its validity and reliability. The results indicated this scale is valuable for the assessment of the purpose of Chinese youth, has theoretical and practical implications for the measurement of beyond-the-self purpose, and can contribute to Chinese youth purpose research and future cross-cultural studies. [ABSTRACT FROM AUTHOR]

Abstract: Reducing lipid accumulation in insulin target tissues is critical for the treatment of type 2 diabetes. This study aimed to develop a biochemical assay in cells for high throughput (HTP) screening of anti-diabetic drugs by reducing lipid accumulation via different mechanisms. We designed a new method to extract triglyceride (TG) with KOH to allow biochemical quantification of TGs for HTP screening in 3T3-L1 cells. This new method was validated for its biochemical properties with identical results of TG obtained with or without KOH (r 2 =0.9978, p <0.001) and a fourfold improvement in TG extraction recovery rate (88–95%, p <0.001) as compared to the conventional chloroform/methanol extraction (12–18%). The ability of this phenotype screening to capture potential anti-diabetic drugs was verified by pharmacological agents well known to alter lipid accumulation by different mechanisms including AMPK activators, fatty acid synthesis inhibitors, PPARγ activator and several lipogenic substrates. To further demonstrate the application of this screening tool for discovery of new anti-diabetic drugs, we screened >200 new candidates selected from Chinese medicine and identified 49 compounds from different classes which reduced TG content by >50% at 1μM or >75% at 10μM. Finally, we tested two selected leads (albiflorin and oxymatrine) in vivo and confirmed their efficacy in reducing visceral adiposity, glucose intolerance and hepatic steatosis in high fat-fed or high fructose-fed mice. Our results indicate that screening for the efficacy on lipid accumulation in cells by biochemical quantification of TGs with KOH extraction is an effective tool for the identification of new anti-diabetic compounds. [Copyright &y& Elsevier]

• Contradictory results have been reported for the potential survival benefit of radiation therapy for metastases. • We investigated the efficacy of metastatic lesion radiotherapy (MLRT) in patients with metastatic nasopharyngeal carcinoma (mNPC). • We found that MLRT offers substantial survival advantages to patients with mNPC. • The recommended regimen for MLRT is to employ a minimum biologically effective dose (BED) of 56 Gy to achieve optimal outcomes. We investigated the efficacy of metastatic lesion radiotherapy (MLRT) in patients with metastatic nasopharyngeal carcinoma (mNPC). Patients with mNPC from three institutions were included in this study. Propensity score matching (PSM) was employed to ensure comparability between patient groups. Overall survival (OS) rates were assessed using the Kaplan–Meier method and compared using the log-rank test. Prognostic factors were identified using univariate and multivariate Cox hazard analyses. Subgroup analyses were conducted to assess the effects of MLRT on specific patient populations. We analyzed data from 1157 patients with mNPC. Patients who received MLRT had significantly better OS than those who did not, both in the original (28 vs. 21 months) and PSM cohorts (26 vs. 23 months). MLRT was identified as an independent favorable predictor of OS in multivariate analyses, with hazard ratios of 0.67. The subgroup analysis results indicated that radiotherapy effectively treated liver, lung, and bone metastatic lesions, particularly in patients with a limited tumor burden. Higher total radiation doses of MLRT (biologically effective dose (BED) ≥ 56 Gy) were associated with improved OS, while neither radiation technique nor dose fractionation independently influenced prognosis. MLRT offers survival advantages to patients diagnosed with mNPC. Patients with limited metastatic burden derive the most benefit from MLRT, and the recommended regimen for MLRT is a minimum BED of 56 Gy for optimal outcomes. [ABSTRACT FROM AUTHOR]

• We aimed to establish an M1 subdivision for personalized prognosis prediction and treatment planning for mNPC. • M1 subdivision demonstrated superior discrimination and clinical utility. • The novel M1 staging strategy provides a refined approach for prognostic prediction and treatment planning. To meet the demand for personalized treatment, effective stratification of patients with metastatic nasopharyngeal carcinoma (mNPC) is essential. Hence, our study aimed to establish an M1 subdivision for prognostic prediction and treatment planning in patients with mNPC. This study included 1239 patients with mNPC from three medical centers divided into the synchronous mNPC cohort (smNPC, n = 556) to establish an M1 stage subdivision and the metachronous mNPC cohort (mmNPC, n = 683) to validate this subdivision. The primary endpoint was overall survival. Univariate and multivariate Cox analyses identified covariates for the decision-tree model, proposing an M1 subdivision. Model performance was evaluated using time-dependent receiver operating characteristic curves, Harrell's concordance index, calibration plots, and decision curve analyses. The proposed M1 subdivisions were M1a (≤5 metastatic lesions), M1b (>5 metastatic lesions + absent liver metastases), and M1c (>5 metastatic lesions + existing liver metastases) with median OS of 34, 22, and 13 months, respectively (p < 0.001). This M1 subdivision demonstrated superior discrimination (C-index = 0.698; 3-year AUC = 0.707) and clinical utility over those of existing staging systems. Calibration curves exhibited satisfactory agreement between predictions and actual observations. Internal and mmNPC cohort validation confirmed the robustness. Survival benefits from local metastatic treatment were observed in M1a, while immunotherapy improved survival in patients with M1b and M1c disease. This novel M1 staging strategy provides a refined approach for prognostic prediction and treatment planning in patients with mNPC, emphasizing the potential benefits of local and immunotherapeutic interventions based on individualized risk stratification. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum (ER) stress is suggested to cause hepatic insulin resistance by increasing de novo lipogenesis (DNL) and directly interfering with insulin signaling through the activation of the c-Jun N-terminal kinase (JNK) and IκB kinase (IKK) pathway. The current study interrogated these two proposed mechanisms in a mouse model of hepatic insulin resistance induced by a high fructose (HFru) diet with the treatment of fenofibrate (FB) 100 mg/kg/day, a peroxisome proliferator-activated receptor α (PPARα) agonist known to reduce lipid accumulation while maintaining elevated DNL in the liver. FB administration completely corrected HFru-induced glucose intolerance, hepatic steatosis, and the impaired hepatic insulin signaling (pAkt and pGSK3β). Of note, both the IRE1/XBP1 and PERK/eIF2α arms of unfolded protein response (UPR) signaling were activated. While retaining the elevated DNL (indicated by the upregulation of SREBP1c, ACC, FAS, and SCD1 and [3H]H2O incorporation into lipids), FB treatment markedly increased fatty acid oxidation (indicated by induction of ACOX1, p-ACC, β-HAD activity, and [14C]palmitate oxidation) and eliminated the accumulation of diacylglycerols (DAGs), which is known to have an impact on insulin signaling. Despite the marked activation of UPR signaling, neither JNK nor IKK appeared to be activated. These findings suggest that lipid accumulation (mainly DAGs), rather than the activation of JNK or IKK, is pivotal for ER stress to cause hepatic insulin resistance. Therefore, by reducing the accumulation of deleterious lipids, activation of PPARα can ameliorate hepatic insulin resistance against increased ER stress. [ABSTRACT FROM AUTHOR]

: We recently showed that bitter melon-derived triterpenoids (BMTs) activate AMPK and increase GLUT4 translocation to the plasma membrane in vitro, and improve glucose disposal in insulin resistant models in vivo. Here we interrogated the mechanism by which these novel compounds activate AMPK, a leading anti-diabetic drug target. BMTs did not activate AMPK directly in an allosteric manner as AMP or the Abbott compound (A-769662) does, nor did they activate AMPK by inhibiting cellular respiration like many commonly used anti-diabetic medications. BMTs increased AMPK activity in both L6 myotubes and LKB1-deficient HeLa cells by 20–35%. Incubation with the CaMKKβ inhibitor, STO-609, completely attenuated this effect suggesting a key role for CaMKKβ in this activation. Incubation of L6 myotubes with the calcium chelator EGTA-AM did not alter this activation suggesting that the BMT-dependent activation was Ca2+-independent. We therefore propose that CaMKKβ is a key upstream kinase for BMT-induced activation of AMPK. [ABSTRACT FROM AUTHOR]

Background and Purpose: The peroxisome proliferator-activated receptor (PPAR)δ has been considered a therapeutic target for diabetes and obesity through enhancement of fatty acid oxidation. The present study aimed to characterize the effects of PPARδ agonists during insulin resistance of the whole body, muscle and liver.Experimental Approach: Wistar rats and C57BL/J6 mice were fed a high fat diet (HF) and then treated with PPARδ agonists NNC61-5920 and GW501516. The effects on insulin resistance were evaluated by hyperinsulinaemic clamp or glucose tolerance tests combined with glucose tracers.Key Results: In HF rats, 3 weeks of treatment with NNC61-5920 reduced the glucose infusion rate (by 14%, P < 0.05) and glucose disposal into muscle (by 20-30%, P < 0.01) during hyperinsulinaemic clamp. Despite increased mRNA expression of carnitine palmitoyltransferase-1, pyruvate dehydrogenase kinase 4 and uncoupling protein 3 in muscle, plasma and muscle triglyceride levels were raised (P < 0.01). Similar metabolic effects were observed after extended treatment with NNC61-5920 and GW501516 to 6 weeks. However, HF mice treated with NNC61-5920 improved their plasma lipid profile, glucose tolerance and insulin action in muscle. In both HF rats and mice, NNC61-5920 treatment attenuated hepatic insulin resistance and decreased expression of stearoyl-CoA desaturase 1, fatty acid translocase protein CD36 and lipoprotein lipase in liver.Conclusions and Implications: PPARδ agonists exacerbated insulin resistance in HF rats in contrast to their beneficial effects on metabolic syndrome in HF mice. These opposing metabolic consequences result from their different effects on lipid metabolism and insulin sensitivity in skeletal muscle of these two species. [ABSTRACT FROM AUTHOR]

Objective: Medium-chain fatty acids (MCFAs) have been reported to be less obesogenic than long-chain fatty acids (LCFAs); however, relatively little is known regarding their effect on insulin action. Here, we examined the tissue-specific effects of MCFAs on lipid metabolism and insulin action.Research Design and Methods: C57BL6/J mice and Wistar rats were fed either a low-fat control diet or high-fat diets rich in MCFAs or LCFAs for 4-5 weeks, and markers of mitochondrial oxidative capacity, lipid levels, and insulin action were measured.Results: Mice fed the MCFA diet displayed reduced adiposity and better glucose tolerance than LCFA-fed animals. In skeletal muscle, triglyceride levels were increased by the LCFA diet (77%, P < 0.01) but remained at low-fat diet control levels in the MCFA-fed animals. The LCFA diet increased (20-50%, P < 0.05) markers of mitochondrial metabolism in muscle compared with low-fat diet-fed controls; however; the increase in oxidative capacity was substantially greater in MCFA-fed animals (50-140% versus low-fat-fed controls, P < 0.01). The MCFA diet induced a greater accumulation of liver triglycerides than the LCFA diet, likely due to an upregulation of several lipogenic enzymes. In rats, isocaloric feeding of MCFA or LCFA high-fat diets induced hepatic insulin resistance to a similar degree; however, insulin action was preserved at the level of low-fat diet-fed controls in muscle and adipose from MCFA-fed animals.Conclusions: MCFAs reduce adiposity and preserve insulin action in muscle and adipose, despite inducing steatosis and insulin resistance in the liver. Dietary supplementation with MCFAs may therefore be beneficial for preventing obesity and peripheral insulin resistance. [ABSTRACT FROM AUTHOR]

Abstract: In the presence of heavy atom perturber LiAc, the silicon dioxide nanoparticle containing rhodamine 6G (R) and dibromoluciferin (D) (R-D-SiO2) can emit strong and stable solid-substrate room temperature phosphorescence signal of R (λex/λem =481/648nm) and D (λex/λem =457/622nm) on the surface of acetyl cellulose membrane (ACM). R-D-SiO2 is used to label triticum vulgare lectin (WGA). Then two types of affinity adsorption reactions, R-D-SiO2-WGA- alkaline phosphatase (ALP) (direct method) and WGA-ALP-WGA-R-D-SiO2 (sandwich method), are carried out on ACM. The conditions and the analytical characteristics for the determination of ALP using affinity adsorption solid-substrate room temperature phosphorimetry (AA-SS-RTP) were studied. For a 0.40-μl drop of sample, results show that the detection limits of the sandwich method are 0.16 ag spot−1(457/622nm) and 0.17 ag spot−1(481/648nm), and the detection limits of the direct method are 0.41 ag spot−1 (457/622nm) and 0.44 ag spot−1 (481/648nm). The contents of ALP in human serum correlated well with those obtained by enzyme-linked immunoassay. This study shows that AA-SS-RTP whether by the sandwich method or the direct method, can combine very well the characteristics of both high sensitivity of SS-RTP and specificity of the immunoreaction. Simultaneously, whether the phosphorescence excitation/emission wavelength of either R or D in R-D-SiO2 is chosen to determine ALP, this can promote the agility and widen the adaptability of AA-SS-RTP. [Copyright &y& Elsevier]