Cathelicidin LL-37 promotes wound healing in diabetic mice by regulating TFEB-dependent autophagy.

Diabetic patients often experience impaired wound healing. Human cathelicidin LL-37 possesses various biological functions, such as anti-microbial, anti-inflammatory, and pro-wound healing activities. Autophagy has important effects on skin wound healing. However, little is known about whether LL-37 accelerates diabetic wound healing by regulating autophagy. In the study, we aimed to investigate the role of autophagy in LL-37-induced wound healing and uncover the underlying mechanisms involved. A full-thickness wound closure model was established in diabetic mice to evaluate the effects of LL-37 and an autophagy inhibitor (3-MA) on wound healing. The roles of LL-37 and 3-MA in regulating keratinocyte migration were assessed using transwell migration and wound healing assays. The activation of transcription factor EB (TFEB) was measured using western blotting and immunofluorescence (IF) assays of its nuclear translocation. The results showed that LL-37 treatment improved wound healing in diabetic mice, whereas these effects were reversed by 3-MA. In vitro, 3-MA decreased the effects of LL-37 on promoting HaCat keratinocyte migration in the presence of high glucose (HG). Mechanistically, LL-37 promoted TFEB activation and resulted in subsequent activation of autophagy, as evidenced by increased nuclear translocation of TFEB and increased expression of ATG5, ATG7, and beclin 1 (BECN1), whereas these changes were blocked by TFEB knockdown. As expected, TFEB knockdown damaged the effects of LL-37 on promoting keratinocyte migration. Collectively, these results suggest that LL-37 accelerates wound healing in diabetic mice by activating TFEB-dependent autophagy, providing new insights into the mechanism by which LL-37 promotes diabetic wound healing.

Metabolic remodeling of glycerophospholipids acts as a signature of dulaglutide and liraglutide treatment in recent-onset type 2 diabetes mellitus.

Aims: As metabolic remodeling is a pathological characteristic in type 2 diabetes (T2D), we investigate the roles of newly developed long-acting glucagon-like peptide-1 receptor agonists (GLP-1RAs) such as dulaglutide and liraglutide on metabolic remodeling in patients with recent-onset T2D. Methods: We recruited 52 cases of T2D and 28 control cases in this study. In the patient with T2D, 39 cases received treatment with dulaglutide and 13 cases received treatment with liraglutide. Using untargeted metabolomics analysis with broad-spectrum LC-MS, we tracked serum metabolic changes of the patients from the beginning to the end of follow-up (12th week). Results: We identified 198 metabolites that were differentially expressed in the patients with T2D, compared to the control group, in which 23 metabolites were significantly associated with fasting plasma glucose. Compared to pre-treatment, a total of 46 and 45 differentially regulated metabolites were identified after treatments with dulaglutide and liraglutide, respectively, in which the most differentially regulated metabolites belong to glycerophospholipids. Furthermore, a longitudinal integration analysis concurrent with diabetes case-control status revealed that metabolic pathways, such as the insulin resistance pathway and type 2 diabetes mellitus, were enriched after dulaglutide and liraglutide treatments. Proteins such as GLP-1R, GNAS, and GCG were speculated as potential targets of dulaglutide and liraglutide. Conclusions: In total, a metabolic change in lipids existed in the early stage of T2D was ameliorated after the treatments of GLP-1RAs. In addition to similar effects on improving glycemic control, remodeling of glycerophospholipid metabolism was identified as a signature of dulaglutide and liraglutide treatments.

Vof16-miR-205-Gnb3 axis regulates hippocampal neuron functions in cognitively impaired diabetic rats.

BACKGROUND: Diabetes is a chronic metabolic disease and an independent risk factor for cognitive damage. Non-protein coding RNAs, including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), are involved in various pathophysiological conditions. METHODS: In this study, cognitive impairment was induced in diabetics rats by streptozotocin (STZ) injection, and the differential lncRNAs and mRNAs in rat hippocampal tissue between control and STZ-treated groups were analyzed with microarray. RESULTS: In the hippocampus of STZ-treated diabetic rats, lncRNA Vof-16, and Gnb3 mRNA were significantly upregulated and silicon analysis showed that Vof-16 and miR-205 share the same miRNA response element (MRE). In addition, the overexpression of Vof-16 in primary hippocampal neurons inhibited the expression of miR-205, and vice versa. Dual luciferase assay verified the binding between Vof-16 and miR-205, and Vof-16 was seen to promote the proliferation of primary hippocampal neurons via sponging miR-205. Silicon analysis predicted that miR-205 could bind with Gnb3, which was verified with dual luciferase assay, and the overexpression of miR-205 could inhibit the protein level of Gnb3, which could be rescued by co-expression with Vof-16. In conclusion, lncRNA Vof-16 regulated Gnb3 expression by competitively binding to miR-205. CONCLUSIONS: These results provided a novel regulation axis for the pathogenesis of STZ-induced diabetes.

Reversal of Functional Brain Activity Related to Gut Microbiome and Hormones After VSG Surgery in Patients With Obesity.

CONTEXT: Vertical sleeve gastrectomy (VSG) is becoming a prioritized surgical intervention for obese individuals; however, the brain circuits that mediate its effective control of food intake and predict surgical outcome remain largely unclear. OBJECTIVE: We investigated VSG-correlated alterations of the gut-brain axis. METHODS: In this observational cohort study, 80 patients with obesity were screened. A total of 36 patients together with 26 normal-weight subjects were enrolled and evaluated using the 21-item Three-Factor Eating Questionnaire (TFEQ), MRI scanning, plasma intestinal hormone analysis, and fecal sample sequencing. Thirty-two patients underwent VSG treatment and 19 subjects completed an average of 4-month follow-up evaluation. Data-driven regional homogeneity (ReHo) coupled with seed-based connectivity analysis were used to quantify VSG-related brain activity. Longitudinal alterations of body weight, eating behavior, brain activity, gastrointestinal hormones, and gut microbiota were detected and subjected to repeated measures correlation analysis. RESULTS: VSG induced significant functional changes in the right putamen (PUT.R) and left supplementary motor area, both of which correlated with weight loss and TFEQ scores. Moreover, postprandial levels of active glucagon-like peptide-1 (aGLP-1) and Ghrelin were associated with ReHo of PUT.R; meanwhile, relative abundance of Clostridia increased by VSG was associated with improvements in aGLP-1 secretion, PUT.R activity, and weight loss. Importantly, VSG normalized excessive functional connectivities with PUT.R, among which baseline connectivity between PUT.R and right orbitofrontal cortex was related to postoperative weight loss. CONCLUSION: VSG causes correlated alterations of gut-brain axis, including Clostridia, postprandial aGLP-1, PUT.R activity, and eating habits. Preoperative connectivity of PUT.R may represent a potential predictive marker of surgical outcome in patients with obesity.

circ_0037128/miR-17-3p/AKT3 axis promotes the development of diabetic nephropathy.

Circular RNAs (circRNAs) play vital roles in the development of diabetic nephropathy (DN). In this study, we investigated the function of circ_0037128 and molecular mechanism via which it regulates diabetic nephropathy development. It was found that expression of circ_0037128 was significantly increased in mouse DN model and high glucose treated mesangial cells (MCs), and circ_0037128 loss-of-function led to reduced cell proliferation and fibrosis in vitro. Moreover, miR-17-3p acts as competitive endogenous RNA (ceRNA) that directly interacts with circ_0037128 through its miRNA response elements (MREs). Consistently, expression of miR-17-3p was remarkably down-regulated in DN model, and negatively regulated cell proliferation and fibrosis. Further investigations revealed that AKT3 was the putative target of miR-17-3p, whose expression was elevated in DN model. In conclusion, we have characterized the function of a novel circ_0037128 and illustrated the significance of circ_0037128-miR-17-3p-AKT3 axis in DN pathogenesis.

Circular RNA Circ_0000064 promotes the proliferation and fibrosis of mesangial cells via miR-143 in diabetic nephropathy.

Diabetic nephropathy (DN) as one of the most frequent microvascular complications of diabetic patients causes chronic renal failure and end-stage renal disease. Noncoding RNAs including circular RNAs (circRNAs) and micro RNAs (miRNAs) were widely reported to play a critical role in numerous human diseases including DN. This research was designed to investigate the role of circ_0000064 in diabetic nephropathy progression. The results showed that circ_0000064 significantly promoted mesangial cells proliferation and aggravated fibrosis in DN. In the subsequent mechanism investigation, we found that circ_0000064 was involved in this process by targeting micro RNA miR-143. The inhibition of miR-143 significantly reverses the effect of circ_0000064 silencing on DN. In conclusion, we demonstrated the regulatory role of circ_0000064 in DN and clarified that circ_0000064 play a role in DN via targeting miR-143. Circ_0000064 and miR-143 also showed the potential as a biomarker for DN.

LncRNA SNHG16 induces proliferation and fibrogenesis via modulating miR-141-3p and CCND1 in diabetic nephropathy.

LncRNAs are reported to participate in the progression of various diseases including diabetic nephropathy. Currently, we reported that SNHG16 was obviously upregulated in db/db mice and high glucose-treated mice mesangial cells. Then, functional experiments showed that SNHG16 silencing significantly inhibited proliferation of mice mesangial cells, which induced the apoptosis and triggered cell cycle arrest. Meanwhile, proliferation-related biomarkers PCNA and Cyclin D1 (CCND1) were greatly repressed. Furthermore, western blot analysis was conducted to test fibrogenesis-associated genes Fibronectin and α-SMA. Meanwhile, the increased protein expression levels of Fibronectin and α-SMA under high glucose conditions were reversed by loss of SNHG16. miR-141-3p has been reported to be involved in various diseases. Then, RNA immunoprecipitation assay revealed the relation between SNHG16 and miR-141-3p. Downregulation of SNHG16 was able to induce expression of miR-141-3p, which was obviously reduced in db/db diabetic nephropathy mice. In addition, CCND1 is a crucial cell cycle master in human diseases. CCND1 was speculated as the target of miR-141-3p and miR-141-3p inhibited CCND1 expression significantly. Meanwhile, we observed that loss of CCND1 greatly repressed mice mesangial cell proliferation and induced cell apoptosis. Taken these together, we revealed for the first time that SNHG16 induced proliferation and fibrogenesis via modulating miR-141-3p and CCND1 in diabetic nephropathy. SNHG16/miR-141-3p/CCND1 axis can suggest a pathological mechanism of progression of diabetic nephropathy.

Knockdown of NEAT1 exerts suppressive effects on diabetic retinopathy progression via inactivating TGF-ß1 and VEGF signaling pathways.

Diabetic retinopathy (DR) is complication resulted from Type 2 diabetes mellitus. Accumulating evidence has proved the functions of long noncoding RNAs (lncRNAs) in the progression of DR. Recent reports exert the numerous regulatory functions of lncRNA nuclear-enriched abundant transcript 1 (NEAT1) in various diseases. However, its implications in DR remain barely known. Therefore, this study was carried out to explore the role of NEAT1 in high-glucose (HG)-triggered injury of human retinal endothelial cells (hRECs). Here, we found the NEAT1 level was significantly elevated in patients with DR, in the retina of diabetic rats and mice. Meanwhile, hRECs under HG stimuli also exhibited an increase of NEAT1. Moreover, the loss of NEAT1 enhanced hRECs proliferation and repressed HG-induced apoptosis, which was accompanied by an upregulation of Bcl-2 and a downregulation of Bax. Subsequently, the knockdown of NEAT1 obviously reduced HG-triggered oxidative stress injury in hRECs. It was reflected that intracellular reactive oxygen species and malondialdehyde level induced by HG were repressed by NEAT1 downregulation, while superoxide dismutase activity was increased. In addition, decreased NEAT1 repressed the inflammatory processes effectively as indicated by the inactivation of inflammatory cytokines Cox-2, interleukin-6, and tumor necrosis factor-α. Furthermore, vascular endothelial growth factor A (VEGF) and transforming growth factor-ß1 (TGF-ß1) expression in patients with DR, DR rats, and HG-incubated hRECs was obviously increased. The silence of NEAT1 could reduce the enhanced expression of VEGF and TGF-ß1 induced by HG. Hence, we concluded NEAT1 might contribute to the development of DR through activating TGF-ß1 and VEGF.

Gut microbiome and serum metabolome alterations in obesity and after weight-loss intervention.

Emerging evidence has linked the gut microbiome to human obesity. We performed a metagenome-wide association study and serum metabolomics profiling in a cohort of lean and obese, young, Chinese individuals. We identified obesity-associated gut microbial species linked to changes in circulating metabolites. The abundance of Bacteroides thetaiotaomicron, a glutamate-fermenting commensal, was markedly decreased in obese individuals and was inversely correlated with serum glutamate concentration. Consistently, gavage with B. thetaiotaomicron reduced plasma glutamate concentration and alleviated diet-induced body-weight gain and adiposity in mice. Furthermore, weight-loss intervention by bariatric surgery partially reversed obesity-associated microbial and metabolic alterations in obese individuals, including the decreased abundance of B. thetaiotaomicron and the elevated serum glutamate concentration. Our findings identify previously unknown links between intestinal microbiota alterations, circulating amino acids and obesity, suggesting that it may be possible to intervene in obesity by targeting the gut microbiota.

Glycated Hemoglobin is Independently Associated with Albuminuria in Young Nondiabetic People with Obesity: A Cross-Sectional Study.

BACKGROUND The aim of this study was to explore the association between glycated hemoglobin (HbA1c) level and albuminuria in young nondiabetic people with obesity. MATERIAL AND METHODS A total of 537 young nondiabetic people with obesity were enrolled in this cross-sectional study, which was approved by the Rui-jin Hospital Ethics Committee. Albuminuria was defined as a urinary albumin-to-creatinine ratio (ACR) ≥30 mg/g. Multivariate logistic regression was used to analyze the association between HbA1c level and albuminuria. RESULTS Urinary ACR progressively increased across the tertiles of HbA1c level (P for trend <0.05). HbA1c levels were positively associated with the risk of albuminuria in the logistic regression analysis after adjustment for confounding factors. The adjusted odds ratio (OR) for albuminuria was 3.72 (95% confidence interval [CI], 1.25-11.00; P=0.017) when comparing between the highest (≥5.7%) and lowest tertiles of HbA1c level (≤5.3%). Moreover, an increment of 1 SD in HbA1c level increased the risk of albuminuria in a fully adjusted model (OR, 1.73; 95% CI, 1.25-2.46). CONCLUSIONS These data suggest that HbA1c level was independently associated with albuminuria in young nondiabetic people with obesity.

Prevalence of polycystic ovary syndrome in Chinese obese women of reproductive age with or without metabolic syndrome.

OBJECTIVE: To compare the prevalence of polycystic ovary syndrome (PCOS) and related clinical characteristics between metabolically unhealthy obese (MUO) and metabolically healthy obese (MHO) women of reproductive age. DESIGN: Cross-sectional clinical study. SETTING: Tertiary hospital. PATIENT(S): We studied 299 MUO and 122 MHO Chinese women matched on body mass index. Metabolically healthy obese was defined as obesity with no more than one metabolic abnormality. Diagnosis of PCOS was based on the revised Rotterdam criteria. INTERVENTION(S): Each subject underwent physical examination, laboratory evaluation, and gynecologic ultrasound for a diagnosis of PCOS or metabolic syndrome (MetS). MAIN OUTCOME MEASURE(S): Prevalence of PCOS was calculated in both groups. Insulin resistance was determined by homeostasis model assessment of insulin resistance or by the insulin sensitivity index derived from Bergman's minimal model. Fat distribution was measured with computerized tomography scan. RESULT(S): Prevalence of PCOS and its components did not differ between MUO and BMI-matched MHO groups (67.89% and 66.96%, respectively). In logistic regression analysis, MetS did not predict the presence of PCOS after adjusting for confounding factors. The MHO group had lower visceral adipose tissue, relatively higher insulin sensitivity, and better ß-cell function, compared with those in the MUO group; but there were no significant differences in sex hormones (except for free T and sex hormone-binding globulin) and ultrasound manifestations between MHO and MUO women. CONCLUSION(S): For the first time, our findings suggest that MetS does not add additional risk for PCOS. In addition, we found that both MUO and MHO are associated with insulin resistance to some extent.