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High blood glucose is one of the risk factors for metabolic disease and INS (insulin) is the key regulatory hormone for glucose homeostasis. Hypoinsulinemia accompanied with hyperglycemia was diagnosed in mice with pancreatic β-cells exhibiting autophagy deficiency; however, the underlying mechanism remains elusive. The role of secretory autophagy in the regulation of metabolic syndrome is gaining more attention. Our data demonstrated that increased macroautophagic/autophagic activity leads to induction of insulin secretion in β-cells both in vivo and in vitro under high-glucose conditions. Moreover, proteomic analysis of purified autophagosomes from β-cells identified a group of vesicular transport proteins participating in insulin secretion, implying that secretory autophagy regulates insulin exocytosis. RAB37, a small GTPase, regulates vesicle biogenesis, trafficking, and cargo release. We demonstrated that the active form of RAB37 increased MAP1LC3/LC3 lipidation (LC3-II) and is essential for the promotion of insulin secretion by autophagy, but these phenomena were not observed in rab37 knockout (rab37-/-) cells and mice. Unbalanced insulin and glucose concentration in the blood was improved by manipulating autophagic activity using a novel autophagy inducer niclosamide (an antihelminthic drug) in a high-fat diet (HFD)-obesity mouse model. In summary, we reveal that secretory autophagy promotes RAB37-mediated insulin secretion to maintain the homeostasis of insulin and glucose both in vitro and in vivo.

Hepatic dysfunction is commonly observed in subjects with hyperthyroidism. Hepassocin is a hepatokine playing an important role in metabolic diseases and exhibiting a hepatic protective effect. Nevertheless, the relationship between hepassocin and hyperthyroidism was still unknown. In the present study, a total of 36 subjects with Graves’ disease were enrolled, and we found that the alanine aminotransferase (ALT) levels were significantly decreased in parallel with the decrement in serum hepassocin concentrations at 6 months after standard treatment for hyperthyroidism. In addition, HepG2 cell line was used to investigate the role of hepassocin in hyperthyroidism-induced hepatic dysfunction. Treatment of hepassocin recombinant protein in HepG2 cells dose-dependently decreased triiodothyronine (T3)-induced ALT and aspartate aminotransferase (AST) elevation. Moreover, hepassocin significantly increased the expression of phosphoenolpyruvate carboxykinase (PEPCK) in a dose-dependent manner. Deletion of hepassocin in HepG2 cells reversed the effects of T3 on PEPCK expressions. Furthermore, we found that T3 increased the expression of hepassocin through a hepatocyte nuclear factor 1α-dependent pathway. Taken together, these results indicated a compensatory increase in serum hepassocin might have a protective role in hyperthyroidism-induced hepatic dysfunction.

Sugar substitutes have been recommended to be used for weight and glycemic control. However, numerous studies indicate that consumption of artificial sweeteners exerts adverse effects on glycemic homeostasis. Although sucralose is among the most extensively utilized sweeteners in food products, the effects and detailed mechanisms of sucralose on insulin sensitivity remain ambiguous. In this study, we found that bolus administration of sucralose by oral gavage enhanced insulin secretion to decrease plasma glucose levels in mice. In addition, mice were randomly allocated into three groups, chow diet, high-fat diet (HFD), and HFD supplemented with sucralose (HFSUC), to investigate the effects of long-term consumption of sucralose on glucose homeostasis. In contrast to the effects of sucralose with bolus administration, the supplement of sucralose augmented HFD-induced insulin resistance and glucose intolerance, determined by glucose and insulin tolerance tests. In addition, we found that administration of extracellular signal-regulated kinase (ERK)-1/2 inhibitor reversed the effects of sucralose on glucose intolerance and insulin resistance in mice. Moreover, blockade of taste receptor type 1 member 3 (T1R3) by lactisole or pretreatment of endoplasmic reticulum stress inhibitors diminished sucralose-induced insulin resistance in HepG2 cells. Taken together, sucralose augmented HFD-induced insulin resistance in mice, and interrupted insulin signals through a T1R3-ERK1/2-dependent pathway in the liver.

Metabolic syndrome (MetS) is a major health issue worldwide accompanied by cardiovascular comorbidities. Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine expressed in cardiomyocytes, adipocytes, macrophages, and endothelial cells. Previous research in elderly subjects revealed that GDF-15 levels were associated with the MetS. However, the association between GDF-15 levels and MetS or its components in the non-elderly subjects remains unclear. In this study, a total of 279 subjects younger than 65-year-old with (n = 84) or without (n = 195) MetS were recruited. MetS was defined according to modified NCEP/ATP III criteria. The GDF-15 levels were measured by an enzyme-linked immunosorbent assay. A multiple linear regression analysis was conducted to identify factors independently associated with GDF-15 levels. Subjects with MetS had higher GDF-15 levels than those without MetS (median (interquartile range), 1.72 ng/mL (1.38, 2.26) vs. 1.63 ng/mL (1.27, 2.07), P = 0.037). With the number of MetS components increased, the GDF-15 levels increased significantly (P for trend = 0.005). Multiple linear regression analysis revealed that the presence of MetS was positively associated with the GDF-15 levels (β = 0.132, P = 0.037). When substituting MetS with its components, only the presence of hyperglycemia was positively associated with the GDF-15 levels after adjustment for covariates (β = 0.193, P = 0.003). Taken together, the presence of the MetS in non-elderly was associated with higher GDF-15 levels. Among the MetS components, only hyperglycemia was significantly associated with the GDF-15 levels. Future longitudinal studies will be needed to explore whether GDF-15 has the potential to be a biomarker of gluco-metabolic dysfunction in non-elderly subjects.

Background: Since non-alcoholic fatty liver disease (NAFLD) is highly associated with obesity, cardiovascular disease, and diabetes, biomarkers for the diagnosis of NAFLD have become an important issue. Although cardiotrophin-1 (CT-1) has a protective effect on the liver in NAFLD animal models, the serum levels of CT-1 in human subjects with NAFLD were still unknown. Objective: The present study aimed to investigate the relationship between the circulating concentration of CT-1 and the severity of hepatic steatosis graded by the value of the controlled attenuation parameter (CAP) in humans. Design and Methods: The study was designed as a cross-sectional study, and a total of 182 subjects were enrolled. Hepatic steatosis measurement was carried out with a Firoscan® device and recorded by CAP. The enrolled study subjects were categorized into CAP < 238 dB/m, 238 ≤ CAP ≤ 259 dB/m, 260 ≤ CAP ≤ 290 dB/m, and CAP > 290 dB/m. Serum CT-1 concentrations were determined by enzyme-linked immunosorbent assay. The association between the serum CT-1 concentration and NAFLD was examined by multivariate linear regression analysis. Results: Body mass index, percentage of body fat, systolic and diastolic blood pressure, alanine aminotransferase (ALT), cholesterol, triglyceride, hemoglobin A1c and homeostatic model assessment for insulin resistance (HOMA-IR) were significantly increased in groups with higher CAP value, whereas high-density lipoprotein cholesterol was significantly decreased. In addition, serum CT-1 concentrations were significantly decreased in subjects with higher CAP values. In multivariate linear regression models, including age, sex, body fat percentage, CAP, high sensitivity- C reactive protein, uric acid, creatinine, ALT, total cholesterol, and HOMA-IR, only age, CAP and uric acid independently associated with CT-1 levels. Moreover, having NAFLD was independently associated with CT-1 after adjustment for sex, obesity and type 2 diabetes. Conclusions: Serum CT-1 concentrations are decreased in subjects with NAFLD and negatively associated with CAP.

Objective:The purpose of the current study was to develop a validated FFQ to evaluate the intake of non-nutritive sweeteners (NNS) in child and adolescent Asian populations.Design:Intensive and overall market research was performed to create the applicable NNS-FFQ with thirteen food categories and 305 items. Six intense sweeteners, including acesulfame potassium, aspartame, sucralose, glycyrrhizin, steviol glycosides and sorbitol, were investigated. The validity and reproducibility of the NNS-FFQ were evaluated. The validity was further assessed by examining the consistency of reported NNS intake compared with urinary biomarkers using Cohen’s κ analysis.Settings:This work was considered to be relevant in Asian societies.Participants:One hundred and two children and adolescents recruited from several clinics were invited to participate in the current study.Results:High content validity indices and high content validity ratio levels were revealed for each sweetener and food category. Reproducibility among subjects was satisfactory. Significant moderate correlations between estimated steviol glycoside/sucralose consumption and sensitive urinary biomarker levels were demonstrated (κ values were 0·59 and 0·45 for steviol glycosides and sucralose, respectively), indicating that the NNS-FFQ can be used to assess an individual’s NNS intake. The dietary intense sweetener consumption pattern evaluated in this measurement was similar to those observed in other Asian countries but differed from those observed in Western populations with respect to types and amounts of NNS.Conclusions:This validated NNS-FFQ can be an applicable and useful tool to evaluate NNS intake in future epidemiological and clinical studies.

Context Maternal lipids during pregnancy and placental growth factors are associated with excess fetal growth. However, how these factors interact to increase the risk of delivering large-for-gestational-age (LGA) neonates remains unclear. In this study, we investigated the relationship between maternal plasma triglycerides (TGs) and free fatty acids (FFAs) during pregnancy, cord blood insulin-like growth factors (IGF), and LGA. Objective In a cell model, we studied the effect of different FAs on placental IGF-1 secretion. Methods This cohort study included pregnant women with term pregnancy and without diabetes or hypertensive disorders in pregnancy. Maternal fasting plasma TGs and FFAs were measured in the second trimester. Cord blood IGF-1, IGF-2, and IGF binding protein-1 and protein-3 were measured at the time of delivery. A human trophoblast cell line, 3A-sub-E, was used to evaluate the effect of different FFAs on placental IGF-1 secretion. Results We recruited 598 pregnant women–neonate pairs. Maternal plasma TG (180 mg/dL [152.5-185.5 mg/dL] vs 166 mg/dL [133-206 mg/dL], P = .04) and cord blood IGF-1 concentrations (72.7 ± 23.0 vs 54.1 ± 22.8 ng/mL, P < .001) were higher in the LGA group and were significantly associated with birth weight z score. Maternal plasma free palmitic acid (PA) and stearic acid (SA), but not oleic acid (OA) or linoleic acid (LA), were significantly associated with cord blood IGF-1 concentrations. In 3A-sub-E cells, treatment with PA, SA, and LA, but not OA, induced IGF-1 expression and secretion. Conclusion Certain FFAs can induce placental IGF-1 secretion, which suggests a potential pathophysiology linking maternal plasma lipids and LGA.

The prevalence of obesity has risen dramatically over recent years, and so has the prevalence of adverse obesity-associated pregnancy outcomes. To combat obesity, the calorie contents of many foods and beverages may be reduced by the use of artificial sweeteners, such as aspartame. However, animal studies suggest that aspartame and its metabolites may exhibit toxicity, and the effects of aspartame on pregnancy are largely unknown. In this study, we treated pregnant mice with aspartame by oral gavage and found that the treatment decreased fasting blood glucose level, whereas systolic blood pressure was elevated. Importantly, the aspartame-treated animals also had low placenta and fetus weights, as well as reduced thickness of the placenta decidua layer. Moreover, aspartame decreased the expression of epithelial-mesenchymal transition proteins and manganese superoxide dismutase (MnSOD) in mouse placentae. In order to clarify the mechanisms though which aspartame affects placenta, we performed experiments on 3A-sub-E trophoblasts. In the cells, aspartame treatments induced cell cycle arrest and reduced the proliferation rate, epithelial-mesenchymal transition, migration activity and invasion activity. We also found that aspartame increased reactive oxygen species (ROS) levels to hyper-activate Akt and downregulate MnSOD expression. Pretreatment with antioxidants or sweet taste receptor inhibitors reversed the effects of aspartame on trophoblast function. We also found that the aspartame metabolite phenylalanine similarly induced ROS production and affected proliferation of trophoblasts. Taken together, our data suggest that aspartame consumption during pregnancy may impact the structure, growth and function of the placenta via sweet taste receptor-mediated stimulation of oxidative stress.

Background Adiposity is a key risk factor for asthma and impaired pulmonary function. Objectives We aimed to identify the critical period of life course adiposity for asthma in childhood and young adulthood, and to determine whether associations of adiposity and asthma vary across ages. Methods Birth weight and body mass index (BMI) from birth to 17 years of age were assessed in 6130 children from the Taiwan Children Health Study. Logistic regression for asthma outcome and linear regression for pulmonary function outcome were used to investigate associations of adiposity with asthma. Seventeen BMI-related single-nucleotide polymorphisms were used to obtain genetic instrumental variables for adiposity to perform Mendelian randomisation (MR) analysis. Results Using both regression model and MR analyses, we confirmed that the critical period of adiposity in predicting childhood asthma would be before age 6 years. Further, we discovered that the sensitive period of adiposity gain related to young adulthood asthma was the prepubertal stage. Risks of asthma at age 17 per unit increase in z-score of the BMI increased from 0.94 (95% CI: 0.79, 1.11) at birth, and became greater than 1.00 between age 11-12, then increased to 1.08 (95% CI: 0.95, 1.22) at age 17. The associations of life course BMI with asthma and pulmonary function impairment at age 12 and with asthma at age 17 increased with age. The aforementioned association was most prominent among central obesity indicators. Conclusions To prevent asthma in childhood and young adulthood, we should aim at promoting healthy growth at the toddler period and prepubertal stage. This article is protected by copyright. All rights reserved.

High-risk pregnancies, such as pregnancies with gestational diabetes mellitus (GDM), are becoming more common and as such, have become important public health issues worldwide. GDM increases the risks of macrosomia, premature infants, and preeclampsia. Although placental dysfunction, including fibrosis is associated with the development of GDM, factors that link these observations remain unknown. Prothymosin α (ProTα) is expressed in the placenta and is involved in cell proliferation and immunomodulation. It also plays an important role in insulin resistance and fibrosis. However, the role of ProTα in GDM is still unclear. In the present study, we found that fibrosis-related protein expressions, such as type I collagen (Col-1) were significantly increased in the placentae of ProTα transgenic mice. With elevated fibrosis-related protein expressions, placental weights significantly increased in GDM group. In addition, placental and circulating ProTα levels were significantly higher in patients with GDM (n=39), compared with the healthy group (n=102), and were positively correlated with Col-1 expression. Mice with streptozotocin (STZ)-induced GDM had increased ProTα, fasting blood glucose, Col-1, and placental weight, whereas plasma insulin levels were decreased. ProTα overexpression enhanced nuclear factor κB (NFκB) activation to increase fibrosis-related protein expressions in 3A-Sub-E trophoblasts, while treatment with an NFκB inhibitor reversed the effect of ProTα on fibrosis-related protein expressions. We further investigated whether ProTα is regulated by hyperglycemia-induced reactive oxygen species (ROS). In conclusion, ProTα increases the amount of placental connective tissue and thus contributes to the pathogenesis of placental fibrosis in GDM. Therefore, ProTα may be a novel therapeutic target for GDM.

In view of the increasing prevalence of gestational diabetes mellitus (GDM) and the increased risks of delivering a macrosomic infant, developing preeclampsia, and suffering a perinatal death due to GDM, GDM has emerged as a growing public health problem. Although the placenta was suggested to play a crucial role in the pathology of GDM, the mechanisms that induce the development of GDM are still obscure. Fibrinogen-like protein (FGL)-1 is a hepatokine that plays an important role in hepatogenesis, as well as in nonalcoholic fatty liver disease and diabetes. Although FGL-1 is also expressed by the placenta, the pathophysiological role of FGL-1 in GDM is still unknown. In this study, FGL-1 levels were evaluated in 45 subjects with (n = 16) or without (n = 29) GDM. We found that FGL-1 was mainly expressed by placental trophoblasts, and FGL-1 expression was significantly higher in subjects with GDM. FGL-1 increased trophoblast proliferation through an extracellular signal-regulated kinase 1/2-dependent pathway. In addition, plasma concentrations of FGL-1 were higher in subjects with GDM, and the increased circulating FGL-1 might contribute to systemic insulin resistance. FGL-1 disrupted the gluconeogenic action of insulin in HepG2 cells, and decreased insulin-induced glucose uptake by L6 myotubes. Taken together, placental FGL-1 possibly plays a role in the impairment of insulin function in the development of GDM, and it might be a novel biomarker for diagnosing GDM.

Context Angiopoietin-like protein 6 (ANGPTL6) is a hepatokine that improves insulin sensitivity in animals. However, serum ANGPTL6 concentration was found to be higher in human participants with diabetes or metabolic syndrome in cross-sectional studies, implying that ANGPTL6 may be induced to counteract hyperglycemia. Objective To investigate whether serum ANGPTL6 can predict incident diabetes and explore whether glucose or insulin can regulate ANGPTL6 expression and secretion. Design This cohort study included adults without diabetes at baseline who were followed every 2 years for incident diabetes. Serum ANGPTL6 concentrations were measured at baseline and during oral glucose tolerance tests (OGTTs). A hepatic cell line, HepG2, and diet-induced obesity mouse model were used to evaluate the response of ANGPTL6 expression and secretion to hyperglycemia and the metabolic syndrome. Results We recruited 1103 participants without diabetes at baseline. During the 4.22-year follow-up, 113 (10.2%) participants developed incident diabetes. Serum ANGPTL6 was negatively associated with the incidence of diabetes (adjusted hazard ratio, 0.77; P = 0.042). However, serum ANGPTL6 level was higher in participants with prediabetes (P = 0.018) and was elevated during OGTT. In HepG2 cells, treatment with glucose, but not insulin, induced ANGPTL6 expression. Hepatic ANGPTL6 expression and serum ANGPTL6 concentrations were significantly higher in mice fed with a high-fat diet than in those fed with a standard chow (both P < 0.05). Conclusion A high serum ANGPTL6 level is associated with a low incidence of diabetes in humans. ANGPTL6 is expressed and secreted in response to hyperglycemia to maintain glucose homeostasis.

Immune checkpoint inhibitors (ICIs) combined with multitarget tyrosine kinase inhibitors (MTKIs) exert a synergistic effect and are effective in unresectable hepatocellular carcinoma (uHCC). However, precise data regarding the real-world clinical applications of these combination therapies in uHCC are lacking. This study compared the treatment efficacy of sorafenib versus lenvatinib in combination with programmed cell death protein-1 (PD-1) inhibitors in patients with uHCC in a clinical setting. Among 208 patients with uHCC treated with PD-1 inhibitors, 88 were administered with ICIs in combination with sorafenib or lenvatinib. The treatment response and survival outcomes were evaluated. Predictors of survival were assessed by multivariate analysis. A total of 49 patients were treated with PD-1 inhibitors combined with sorafenib, and 39 patients were treated with PD-1 inhibitors combined with lenvatinib. The lenvatinib group exhibited a stronger objective response rate (ORR) (20.51% vs. 16.33%) and had a higher disease control rate (41.03% vs. 28.57%) than did the sorafenib group. The median overall survival was longer in the lenvatinib group than the sorafenib group (13.1 vs. 7.8 months; hazard ratio = 0.39, p = 0.017). The incidence of treatment-related adverse events was similar. PD-1 inhibitors combined with lenvatinib can be a feasible treatment strategy for HCC patients receiving MTKI-based combination therapy. PD-1 inhibitors combined with lenvatinib resulted in more favorable survival outcomes without increased toxic effects compared with PD-1 inhibitors with sorafenib. Additional larger-scale and prospective studies should be conducted to verify the study results.

Fibrinogen-like-protein 1 (FGL1) is a novel hepatokine that plays an important role in hepatic steatosis and insulin resistance. Although FGL1 expression can be detected in adipose tissues, the functions of FGL1 in adipose tissues are still unknown. In this study, 356 participants with (body mass index (BMI) ≥25 kg/m2 ; n = 134) or without obesity (BMI

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease globally, and it is strongly associated with obesity. To combat obesity, artificial sweeteners are often used to replace natural sugars, and sucralose is one of the most extensively used sweeteners. It was known that sucralose exerted effects on lipid metabolism dysregulation, and hepatic inflammation; however, the effects of sucralose on hepatic steatosis were still obscure. In this study, we found that supplements of sucralose enhanced high-fat-diet (HFD)-induced hepatic steatosis. In addition, treatment of sucralose increased reactive oxygen species (ROS) generation and induced endoplasmic reticulum (ER) stress in HepG2 cells. Pretreatment of ROS or ER stress inhibitors reversed the effects of sucralose on lipogenesis. Furthermore, pretreatment of taste receptor type 1 membrane 3 (T1R3) inhibitor or T1R3 knockdown reversed sucralose-induced lipogenesis in HepG2 cells. Taken together, sucralose might activate T1R3 to generate ROS and promote ER stress and lipogenesis, and further accelerate to the development of hepatic steatosis.

Epidemic obesity and diabetes have led to increased use of low-calorie sweeteners. Although several studies have suggested that consumption of artificial sweeteners, such as aspartame and saccharin, might have negative effects, the potential impacts of natural sweeteners on human health remain largely unknown.The deferential effects of short term and long term consumption of sorbitol on glucose homeostasis in mice by oral gavage. The glucose homeostasis and utility were evaluated by both oral or intraperitoneal glucose tolerance tests. Insulin levels were determined using enzyme-linked immunosorbent assay. Changes of gut microbiome were evaluated by 16S rRNA gene sequencing, and analyzed by principal components analysis.Bolus feeding of sorbitol by gavage significantly increased plasma insulin concentrations and decreased fasting blood glucose levels. Intriguingly, long-term sorbitol gavage for four weeks showed no significant effects on intraperitoneal glucose tolerance test outcomes, but it induced glucose intolerance according to the oral glucose tolerance test. Thus, we tested whether long-term sorbitol gavage might alter the relative abundances of gut microbiome constituents in mice. Principal components analysis indicated that long-term sorbitol intake indeed caused significant changes to the gut microbiome. In particular, we found that long-term sorbitol intake significantly decreased the relative abundances of Bifidobacterium, Lachnospiraceae UCG 001, Lachnospiraceae NK4A136, Eubacterium ventriosum, Candidatus Arthromitus, and Ruminococcus torques. We also found that long-term sorbitol increased the relative abundances of Helicobacter, Tyzzerella, Alistipes, and Prevotella 9.Long-term sorbitol consumption may change the composition of the gut microbiome and potentially induce glucose intolerance.

Growth differentiation factor 15 (GDF15) is a stress-response cytokine which belongs to the transforming growth factor β superfamily. Although GDF15 was initially found to have a role in metabolic diseases, the association between GDF15 and dysglycemic status remains inconclusive. Thus, the aim of this study was to examine the relationships between GDF15 and different glycemic statuses in non-obese subjects. We enrolled 502 non-obese subjects, among individuals who had normal glucose tolerance (NGT; n=125), isolated impaired fasting glucose (IFG; n=116), isolated impaired glucose tolerance (IGT; n=106), IFG plus IGT (n=27), and newly diagnosed diabetes (NDD; n=128). A multivariate linear regression analysis of GDF15 levels was used to find independent predictors. The median (IQR) GDF15 levels were 1641.0 (1187.0–1985.5) pg/mL, 1656.1 (1226.8–2379.7) pg/mL, 1487.8 (1145.9–1987.2) pg/mL, 1722.2 (1172.9–1939.0) pg/mL, and 2204.5 (1767.4–2919.1) pg/mL in NGT, IFG, IGT, IFG plus IGT, and NDD groups, respectively. The NDD group had significantly higher GDF15 levels than those with NGT, IFG, IGT, and IFG plus IGT. The IFG group had a significantly higher GDF15 value than the NGT group. In multivariate linear regression analysis, IFG (beta=0.145, 95% CI 192.487 to 740.937, p=0.001), NDD (beta=0.227, 95% CI 390.459 to 888.145, p

Background Hypothalamic inflammation including astrogliosis and microglia activation occurs after intake of high fat diet (HFD) in rodent models or in obese individuals. However, the effect of chronic HFD feeding on oligodendrocytes (OLGs), a myelin-producing glial population in the central nervous system (CNS), remains unclear. In this study, we used 8-week old male C57BL/6 mice fed by HFD for 3–6 months to induce chronic obesity. Results The transmission electron microscopy imaging analysis showed that the integrity of hypothalamic myelin was disrupted after HFD feeding for 4 and 6 months. Moreover, the accumulation of Iba1+-microglia with an amoeboid hypertrophic form was continually observed in arcuate nucleus of HFD-fed mice during the entire feeding time period. Interleukin-33 (IL-33), a tissue alarmin upon injury to the CNS, was detected with an increased level in hypothalamus after HFD feeding for 3 and 4 months. Furthermore, the in vitro study indicated that exposure of mature OLGs to IL-33 impaired OLG cell structure along with a decline in the expression of myelin basic protein. Conclusions Altogether, our findings demonstrate that chronic HFD feeding triggers hypothalamic myelin disruption in accompany with IL-33 upregulation and prolonged microglial activation in hypothalamus. Given that the addition of exogenous IL-33 was harmful for the maturation of OLGs, an increase in IL-33 by chronic HFD feeding might contribute to the induction of hypothalamic myelin disruption. Electronic supplementary material The online version of this article (10.1186/s12868-019-0516-6) contains supplementary material, which is available to authorized users.

Metabolic disorders induce adverse effects on brain functions. The hippocampus is one of the most vulnerable regions to metabolic disorders. Disrupted neuroplasticity is a major cause of hippocampus-related behavioral impairments, including memory loss, anxiety, and depression. Astrocytes support processes of neuroplasticity. However, whether metabolic disorders induce changes in astrocytes and their roles in affective disorders is relatively unclear. To answer this question, we fed 8-week-old male C57BL/6 mice with a high-fat diet (HFD) for 12 weeks to induce metabolic disruption and then examined their performance of hippocampus-related memory, and anxiety- and depression-like behaviors. The morphology of astrocytes and the expression of astrocytic neuroplasticity-related proteins in the hippocampus were also assessed. The results showed that HFD led to obesity, systemic insulin resistance and dysregulated lipid metabolism in mice. HFD induced depression-like behaviors, but not anxiety or memory impairment. Furthermore, HFD increased the expression of GFAP, shortened the processes of GFAP+ cells, and downregulated the expression of astrocytic neuroplasticity-related protein, GLAST, GLT-1, and connexin-43 in the hippocampi. In conclusion, HFD disturbs the function of hippocampal astrocytes and induces depression-like behaviors in mice. A decrease of hippocampal glutamate transporters may play a critical role in the pathogenesis of metabolic disorder-related depression.

Background: The oncogenic Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation was reported to be the signature genetic event in most cases of pancreatic ductal adenocarcinoma (PDAC). Hepassocin (HPS/FGL1) is involved in regulating lipid metabolism and the progression of several cancer types; however, the underlying mechanism of HPS/FGL1 in the KRAS mutant PDAC cells undergoing eicosapentaenoic acid (EPA) treatment remains unclear. Methods: We measured HPS/FGL1 protein expressions in a human pancreatic ductal epithelial (HPNE) normal pancreas cell line, a KRAS-wild-type PDAC cell line (BxPC-3), and KRAS-mutant PDAC cell lines (PANC-1, MIA PaCa-2, and SUIT-2) by Western blot methods. HEK293T cells were transiently transfected with corresponding KRAS-expressing plasmids to examine the level of HPS expression with KRAS activation. We knocked-down HPS/FGL1 using lentiviral vectors in SUIT-2 cells and measured the cell viability by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clonogenicity assays. Furthermore, a lipidomic analysis was performed to profile changes in lipid metabolism after HPS/FGL1 knockdown. Results: We found that the HPS/FGL1 level was significantly upregulated in KRAS-mutated PDAC cells and was involved in KRAS/phosphorylated (p)-signal transduction and activator of transcription 3 (STAT3) signaling, and the knockdown of HPS/FGL1 in SUIT-2 cells decreased cell proliferation through increasing G2/M cell cycle arrest and cyclin B1 expression. In addition, the knockdown of HPS/FGL1 in SUIT-2 cells significantly increased omega-3 polyunsaturated fatty acids (PUFAs) and EPA production but not docosahexaenoic acid (DHA). Moreover, EPA treatment in SUIT-2 cells reduced the expression of de novo lipogenic protein, acetyl coenzyme A carboxylase (ACC)-1, and decreased p-STAT3 and HPS/FGL1 expressions, resulting in the suppression of cell viability. Conclusions: Results of this study indicate that HPS is highly expressed by KRAS-mutated PDAC cells, and HPS/FGL1 plays a crucial role in altering lipid metabolism and increasing cell growth in pancreatic cancer. EPA supplements could potentially inhibit or reduce ACC-1-involved lipogenesis and HPS/FGL1-mediated cell survival in KRAS-mutated pancreatic cancer cells.

Background Obesity is an independent risk factor for metabolic disorders including diabetes. The Hedgehog-interacting protein (Hhip) is a negative regulator in tissue remodeling, and inhibits the proliferation of adipocytes and promotes their differentiation. In addition, Hhip was positively associated with diabetes. However, relationship between Hhip and obesity in the human body remain unclear. Methods Participants receiving a physical checkup were recruited. Anthropometric and biochemical data were collected. Serum Hhip levels were determined by ELISA. Subjects were classified into normal-weight, overweight, and obese groups based on their body mass index (BMI). The association between Hhip and obesity was examined by a multivariate linear regression analysis.Results In total, 294 subjects who were either of a normal weight (n=166), overweight (n=90), or obese (n=38) were enrolled. Hhip concentrations were 6.51±4.86, 5.79±4.33, and 3.97±3.4 ng/ml in normal-weight, overweight, and obese groups, respectively (p for trend=0.032). Moreover, the regression analysis showed that BMI (β=-0.144, 95% confidence interval (CI)=-0.397~-0.046, p=0.013) was negatively associated with Hhip concentrations after adjusting for sex and age. Being overweight (β=-0.181, 95% CI=-3.311~-0.400, p=0.013) and obese (β=-0.311, 95% CI=-6.393~-2.384, pConclusions Our results showed that overweight and obese subjects had lower Hhip concentrations than those of a normal weight. Being overweight and obese were negatively associated with Hhip concentrations. Hhip might be a link between obesity and diabetes.

Supplementary Tables for the manuscript "Serum Angiopoietin-like Protein 6, Risk of Type 2 Diabetes, and Response to Hyperglycemia: A Prospective Cohort Study".

Vascular adhesion protein-1 (VAP-1) can enhance tissue glucose uptake in cell studies and normalize hyperglycemia in animal studies. However, serum VAP-1 concentration (sVAP-1) is higher in subjects with diabetes in cross-sectional studies. In this cohort study, we test our hypothesis that sVAP-1 is increased in prediabetes to counteract hyperglycemia and is associated with incident diabetes negatively. From 2006 to 2012, 600 subjects without diabetes from Taiwan Lifestyle Study were included and followed regularly. Diabetes was diagnosed if FPG ≥ 126 mg/dL (7 mmol/L), 2-h plasma glucose (2hPG) during an oral glucose tolerance test (OGTT) ≥ 200 mg/dL (11.1 mmol/L), or hemoglobin A1c (HbA1c) ≥ 6.5%, or if the subject received anti-diabetic medications. Abdominal fat areas were measured by abdominal computed tomography and sVAP-1 was analyzed by ELISA. sVAP-1 was higher in subjects with prediabetes (p

Background: The notion that exposure to chronic stress predisposes individuals to developing type 2 diabetes (T2D) has gained much attention in recent decades. Long-term stress induces neuroadaptation in the amygdala and increases corticosterone levels. Corticosterone, the major stress hormone in rodents, induces insulin resistance and obesity in mice. However, little is known about whether the stress-induced amygdalar neuroadaptation could promote the risk of T2D. Methods: We used an 11-week high-fat diet (HFD) feeding paradigm to induce insulin dysfunction in mice, followed by implementation of a 10-day social defeat (SD) stress protocol. Results: Mice receiving SD at the beginning of the HFD feeding aggravated HFD-induced insulin resistance and white adipose tissue expansion. HFD mice had higher levels of plasma corticosterone, which was not affected by the SD. The SD stress upregulated the expression of TrkB and synaptotagmin-4 in the amygdala of HFD mice. Bilateral lesions of the central amygdalae before SD stress inhibited the stress-induced aggravating effect without affecting the HFD-induced elevation of plasma corticosterone. Conclusions: Stress aggravates HFD-induced insulin resistance and neuroadaptation in the amygdala. The HFD-induced insulin resistance is amygdala-dependent. Understanding the role of stress-induced amygdalar adaptation in the development of T2D could inform therapies aimed at reducing chronic stressors to decrease the risk for T2D.

Context High glucose generates reactive oxygen species (ROS) and contributes to glucotoxicity in hepatocytes, and hyperglycemia causes structural and functional damage to the liver. However, only a mild hepatic dysfunction was observed in subjects with hyperglycemic crisis, implying a factor exists to exert a hepatic protective effect. Hepassocin is a hepatokine that modulates the proliferation and metabolism of hepatocytes and also exerts protective activity in liver injury. However, its role in hyperglycemic crisis-induced hepatic dysfunction remains unknown. Objective To investigate the possible hepatic protection effects of hepassocin in hyperglycemic crisis. Design, setting, and patients Plasma hepassocin concentrations and routine biochemistry were measured in 21 patients with hyperglycemic crisis before and after standard treatments. The effects of hepassocin on hepatic functions were evaluated in streptozotocin-induced hyperglycemic mice (STZ mice). HepG2 cells were used to clarify the possible mechanisms regulating hepassocin expression. Results Plasma hepassocin concentrations decreased significantly in subjects with hyperglycemic crisis after standard treatment accompanied by improved hepatic functions. Correction of hyperglycemia in STZ mice also decreased the hepatic hepassocin expression. Injection of recombinant hepassocin improved hepatic functions and histologic changes and increased the expression of antioxidative stress proteins, including superoxide dismutase 1 (SOD1). In HepG2 cells, high glucose increased hepassocin expression through signal transducer and activator of transcription 3 and hepatocyte nuclear factor-related pathways. We also demonstrated that hepassocin increased SOD1 expression through an extracellular signal-regulated kinase 1/2 nuclear factor erythroid-2-related factor 2 pathway, decreasing ethyl acetate-induced ROS production and improving cell viability. Conclusions Increased hepassocin secretion in hyperglycemic crisis might offset the deleterious effects of hyperglycemia on hepatocytes.

Background: The prevalence of diabetes is rapidly increasing worldwide and is highly associated with the incidence of cancers. In order to prevent diabetes, early diagnosis of prediabetes is important. However, biomarkers for prediabetes diagnosis are still scarce. The hedgehog-interacting protein (Hhip) is important in embryogenesis and is known to be a biomarker of several cancers. However, Hhip levels in subjects with diabetes are still unknown. Methods: In total, 314 participants were enrolled and divided into normal glucose tolerance (NGT, n = 75), impaired fasting glucose (IFG, n = 66), impaired glucose tolerance (IGT, n = 86), and newly diagnosed diabetes (NDD, n = 87) groups. Plasma Hhip levels were determined by an ELISA. The association between the Hhip and the presence of diabetes was examined by a multivariate linear regression analysis. Results: There were significant differences in the body mass index, systolic and diastolic blood pressure, fasting plasma glucose (FPG), post-load 2-h glucose, hemoglobin A1c (A1C), C-reactive protein, total cholesterol, triglyceride, and high- and low-density lipoprotein cholesterol levels among the groups. Concentrations of the Hhip were 2.45 &plusmn, 2.12, 4.40 &plusmn, 3.22, 4.44 &plusmn, 3.64, and 6.31 &plusmn, 5.35 ng/mL in subjects in the NGT, IFG, IGT, and NDD groups, respectively. In addition, we found that A1C and FPG were independently associated with Hhip concentrations. Using NGT as a reference group, IFG, IGT, and NDD were all independently associated with Hhip concentrations. Conclusions: Hhip was positively associated with prediabetes and type 2 diabetes mellitus.

Secretogranin III (SCG3) plays a crucial role in the biogenesis of secretory granules in endocrine cells, and thus affects glucose homeostasis by regulating insulin secretion by pancreatic beta cells. Insulin resistance and compensatory hyperinsulinemia are hallmarks of metabolic syndrome (MetS). However, the role of SCG3 in MetS remains unclear. Therefore, we investigated the relationship between serum SCG3 levels and metabolic parameters in subjects with and without MetS. This was a case control study, and 295 subjects were recruited. Serum SCG3 concentrations were compared between groups. Associations between SCG3 levels and clinico-metabolic parameters were also examined. We found serum SCG3 levels were higher in the MetS group than non-MetS group (122.6 &plusmn, 79.2 vs. 90.6 &plusmn, 58.5 nmol/L, p = 0.009). Specifically, elevated SCG3 levels were found in subjects with high fasting plasma glucose (FPG) levels, central obesity, or hypertriglyceridemia. Additionally, MetS was an independent factor of serum SCG3 levels in multivariate linear regression analyses. Moreover, FPG, free fatty acids, and waist circumference were positively associated with serum SCG3 concentrations after adjusting for insulin levels, high-sensitivity C-reactive protein, and cardiovascular risk factors. In conclusion, serum SCG3 concentrations were higher in subjects with MetS and were independently associated with FPG levels.

Obesity is a public health problem that has raised concerns worldwide and is often associated with hepatic steatosis. Hepassocin is a novel hepatokine that causes hepatic steatosis and induces insulin resistance (IR). However, the role of hepassocin in obesity remains obscure. Thus, the aim of this study was to investigate the relationship between hepassocin levels and obesity. In total, 371 subjects who had a normal weight (NW), were overweight, or were obese were enrolled. We found that hepassocin levels in subjects who were overweight (6,705 ± 1,707 pg/ml) or obese (7,335 ± 2,077 pg/ml) were significantly higher than those of subjects with a NW (5,767 ± 1,500 pg/ml) (p < .001, test for trend). A multiple linear regression analysis showed that the body-mass index, waist circumference, nonalcoholic fatty liver disease, and homeostatic model assessment of IR were independently associated with hepassocin after adjusting for age, sex, high-sensitivity C-reactive protein, systolic blood pressure, high-density lipoprotein-cholesterol, log triglycerides, alanine transaminase, and the estimated glomerular filtration rate. This study provides evidence that subjects who were overweight or obese had significantly higher hepassocin levels than those with a NW. Hepassocin may be a useful biomarker in managing obesity and its related metabolic dysregulation.

Additional file 1: Table S1. A list of animals used for the assays indicated in figures and supplementary figures; Figure S1. Anatomical diagram; Figure S2. Examination of myelin structure in the hypothalamus of mice receiving Chow and HFD feeding for 3 months; Figure S3. Examination of the body weight, water intake, food intake and calorie intake of mice receiving Chow and HFD; Figure S4. Microglia activation induced by HFD feeding in hypothalamic arcuate nucleus at 2 month after feeding; Figure S5. Exposure to IL-33 hinders the maturation of rat oligodendrocytes.

Background: The oncogenic Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation was reported to be the signature genetic event in most cases of pancreatic ductal adenocarcinoma (PDAC). Hepassocin (HPS/FGL1) is involved in regulating lipid metabolism and the progression of several cancer types, however, the underlying mechanism of HPS/FGL1 in the KRAS mutant PDAC cells undergoing eicosapentaenoic acid (EPA) treatment remains unclear. Methods: We measured HPS/FGL1 protein expressions in a human pancreatic ductal epithelial (HPNE) normal pancreas cell line, a KRAS-wild-type PDAC cell line (BxPC-3), and KRAS-mutant PDAC cell lines (PANC-1, MIA PaCa-2, and SUIT-2) by Western blot methods. HEK293T cells were transiently transfected with corresponding KRAS-expressing plasmids to examine the level of HPS expression with KRAS activation. We knocked-down HPS/FGL1 using lentiviral vectors in SUIT-2 cells and measured the cell viability by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clonogenicity assays. Furthermore, a lipidomic analysis was performed to profile changes in lipid metabolism after HPS/FGL1 knockdown. Results: We found that the HPS/FGL1 level was significantly upregulated in KRAS-mutated PDAC cells and was involved in KRAS/phosphorylated (p)-signal transduction and activator of transcription 3 (STAT3) signaling, and the knockdown of HPS/FGL1 in SUIT-2 cells decreased cell proliferation through increasing G2/M cell cycle arrest and cyclin B1 expression. In addition, the knockdown of HPS/FGL1 in SUIT-2 cells significantly increased omega-3 polyunsaturated fatty acids (PUFAs) and EPA production but not docosahexaenoic acid (DHA). Moreover, EPA treatment in SUIT-2 cells reduced the expression of de novo lipogenic protein, acetyl coenzyme A carboxylase (ACC)-1, and decreased p-STAT3 and HPS/FGL1 expressions, resulting in the suppression of cell viability. Conclusions: Results of this study indicate that HPS is highly expressed by KRAS-mutated PDAC cells, and HPS/FGL1 plays a crucial role in altering lipid metabolism and increasing cell growth in pancreatic cancer. EPA supplements could potentially inhibit or reduce ACC-1-involved lipogenesis and HPS/FGL1-mediated cell survival in KRAS-mutated pancreatic cancer cells.

Type 2 diabetes is highly correlated with nonalcoholic fatty liver disease (NAFLD). Hepatocyte-derived fibrinogen-related protein 1 (HFREP1) is a hepatokine that mediates NAFLD development; however, the role of HFREP1 in the development of insulin resistance and diabetes remains obscure. A total of 193 age- and sex-matched participants with normal glucose tolerance, impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and newly diagnosed diabetes (NDD) were recruited for a cross-sectional study. Plasma HFREP1 levels were measured and multivariate linear regression analysis was used to evaluate the relationship between HFREP1, IFG, IGT and NDD. The causal relationship between HFREP1 and insulin resistance was then investigated in animal and cell models. Glucose and insulin tolerance tests, and euglycaemic–hyperinsulinaemic clamp, were used to evaluate insulin sensitivity in animals with Hfrep1 overexpression or knockdown in liver by lentiviral vectors. HepG2 cells were used to clarify the possible mechanism of HFREP1-induced insulin resistance. Plasma HFREP1 concentrations were significantly increased in participants with IFG, IGT and NDD. HFREP1 concentrations were independently associated with fasting plasma glucose levels, insulin resistance, IFG, IGT and NDD. Injection of recombinant HFREP1 or Hfrep1 overexpression induced insulin resistance in mice, and HFREP1 disrupted insulin signalling to induce insulin resistance through an extracellular signal-regulated kinase (ERK)1/2-dependent pathway. Moreover, hepatic knockdown of HFREP1 improved insulin resistance in both mice fed a high-fat diet and ob/ob mice. These findings highlight the crucial role of HFREP1 in insulin resistance and diabetes, and provide a potential strategy and biomarker for developing therapeutic approaches to combat these diseases.