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Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease. Increased incidence of T1D was reported in patients receiving IFN-α treatment. However, the exact mechanisms of IFN-α that facilitate the pathogenesis of T1D are not fully understood. To explore the mechanism of IFN-α on the immune system and islets, non-obese diabetic (NOD) mice were injected with IFN-α and the progression of autoimmune insulitis was assessed by haematoxylin and eosin (HE) staining, immunohistochemical and flow cytometry analysis. Transcriptional profiling of islets treated with IFN-α was explored by RNA-seq. IFN-α induced antigen presentation was evaluated by qRT-PCR, western blot and immunofluorescence, and key transcription factors were inhibited by small interfering RNAs (siRNAs). Our data show that IFN-α contributed to the progression of autoimmune insulitis in NOD mice by promoting the proliferation of CD8+ T cells. IFN-α upregulated antigen presentation related genes MHC I, TAP1, B2M, PSMB8, NLRC5 and transcriptional regulator STAT1, STAT2, IRF7 at a time and dose-dependent manner. The silence of STAT1 or STAT2 both weakened IFN-α-induced increase of antigen presenting related molecules. IRF7 was also merely influenced by STAT1 silence. The knockdown of IRF7 decreased the IFN-α induced expressions of TAP1, PSMB8 and MHC I and prevented the expression of STAT2 but not STAT1. Our study demonstrated that STAT1-IRF7-MHC I complex axis were crucial for IFN-α signalling in islets, and created positive feedback through IRF7-STAT2 cascade amplifying signals which accelerated the process of T1D.

The binary nature of metabolic syndrome (MetS) cannot quantitatively describe the severity of metabolic abnormalities. We aim to establish a metabolic integral score (MIS) model to quantify the severity and polarity of metabolic disorders and their relationship with insulin sensitivity and secretion.We performed factor analysis on 9950 participants from a cross-sectional study conducted in China. The MIS model was established using 10 variables including body mass index (BMI), waist circumference, hip circumference, glycosylated hemoglobin (HbA1c), fasting and 2-h plasma glucose (FPG, 2h-PG), systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein (HDL) and triglyceride (TG) levels. Four common factors were identified as "glucose factor," "obesity factor," "blood pressure factor," and "lipid factor," respectively, in MIS model (KMO = 0.755, P 0.001). MIS = 0.433 × Factor 1 + 0.267 × Factor 2 + 0.172 × Factor 3 + 0.128 × Factor 4. Insulin sensitivity and β-cell function decreased with the increase of MIS (P 0.001). We classified four metabolic tendencies according to factor quartiles. Individuals in Tendency 1 (severe hyperglycemia) had the worst β-cell function. Tendency 3 (severe hypertension) had the best insulin sensitivity. Tendency 4 (severe dyslipidemia) had preferable β-cell function (P 0.05).Our MIS model provides a quantitative scoring system to assess various patterns of metabolic abnormality that indicate different underlying pathophysiology.

Islets have complex heterogeneity and subpopulations. Cell surface markers representing alpha, beta and delta cell subpopulations are urgently needed for investigations to explore the compositional changes of each subpopulation in obesity progress and diabetes onset, and the adaptation mechanism of islet metabolism induced by a high-fat diet (HFD).Single-cell RNA sequencing (scRNA-seq) was applied to identify alpha, beta and delta cell subpopulation markers in an HFD-induced mouse model of glucose intolerance. Flow cytometry and immunostaining were used to sort and assess the proportion of each subpopulation. Single-cell proteomics was performed on sorted cells, and the functional status of each alpha, beta and delta cell subpopulation in glucose intolerance was deeply elucidated based on protein expression.A total of 33,999 cells were analysed by scRNA-seq and clustered into eight populations, including alpha, beta and delta cells. For alpha cells, scRNA-seq revealed that the Ace2We identified ACE2, CD81 and GLUT2 as surface markers to distinguish, respectively, alpha, beta and delta cell subpopulations with heterogeneous maturation and function. The changes in the proportion and functional status of islet endocrine subpopulations reflect the metabolic adaptation of islets to high-fat stress, which weakened the function of alpha cells and enhanced the function of beta and delta cells to bring about glycaemic homeostasis. Our findings provide a fundamental resource for exploring the mechanisms maintaining each islet endocrine subpopulation's fate and function in health and disease.The scRNA-seq analysis datasets from the current study are available in the Gene Expression Omnibus (GEO) repository under the accession number GSE203376.

This study aims to reveal the association betweenWe included 2505 healthy controls based on oral glucose tolerance test (OGTT), 1736 unrelated T2D, and 1003 unrelated autoantibody-positive T1D individuals. Binary logistic regression was performed to evaluate the relationships between rs864745 inWe did not find any association between rs864745 inThe common

Recent meta-genome-wide association studies identified several genetic variants associated with beta-cell function in type 1 diabetes (T1D). The aim of this study was to investigate the associations between these variants and T1D risk, C-peptide levels, islet-specific autoantibodies, and lipid levels in Chinese Han population. A total of 1005 unrelated autoantibody-positive T1D cases and 1417 healthy controls were included, which were genotyped for rs559047, rs9260151, and rs3135002. T1D individuals were measured for both C-peptide and lipid levels. Logistic regression models were used to examine these associations. We found that rs3135002 A allele showed a genome-wide significant association with T1D risk (OR = 0.22, 95% CI = 0.17–0.30; P = 7.49 × 10−27), and significant heterogeneity of effect size was observed between early-onset and later-onset T1D subgroups (I2 = 80% and P = 0.026). Rs559047 had a nominal association with fasting C-peptide levels in newly diagnosed T1D individuals (P = 0.036). Moreover, rs3135002 A allele was significantly associated with GADA positivity (OR = 0.52, 95% CI = 0.30–0.91, P = 0.02). In addition, nominal correlations were observed with HDL levels for rs559047 (P = 0.042), while LDL levels for rs9260151 (P = 0.032) in T1D individuals. Our results indicate that there are both similarities and differences for the associations of genetic variants among T1D development, progression, and related autoimmunity, metabolic traits.

T2D and T1D are phenotypically heterogeneous. This study aims to reveal the relationship between the common SLC30A8 rs13266634 variant and subgroups of T2D and T1D and their clinical characteristics.We included 3158 OGTT-based healthy controls, unrelated 1754 T2D, and 1675 autoantibody-positive T1D individuals. The associations between rs13266634 and subtypes of T2D, T1D, autoantibody status and glycemic-related quantitative traits were performed by binary logistic regression analysis under the additive model and multiple linear regression with appropriate adjustment.We found that the T allele of rs13266634 was protectively associated with lean (OR = 0.810, P = 6.91E-04) but not obese T2D with considerable heterogeneity (P = 0.018). This allele also conferred significant protection with T1D of single (OR = 0.847, P = 9.76E-03), but not multi autoantibodies with substantial heterogeneity (P = 0.005). This variant significantly affected OGTT-related insulin release in lean (P = 2.66E-03, 3.88E-03 for CIR and DI, respectively) but not obese healthy individuals. Furthermore, rs13266634 T allele correlated with the risk of ZnT8A (OR = 1.440, P = 3.31E-05) and IA-2A (OR = 1.219, P = 1.32E-03) positivity, with more effect size in children/adolescents compared with adult-onset T1D subtypes.These suggested that the SLC30A8 rs13266634 variant might be put into genetic risk scores to assess the risk of the subtypes of T1D and T2D and their related clinical features.

It is estimated that ∼1% of European ancestry patients clinically diagnosed with type 1 diabetes (T1D) actually have monogenic forms of the disease. Because of the much lower incidence of true T1D in East Asians, we hypothesized that the percentage would be much higher. To test this, we sequenced the exome of 82 Chinese Han patients clinically diagnosed with T1D but negative for three autoantibodies. Analysis focused on established or proposed monogenic diabetes genes. We found credible mutations in 18 of the 82 autoantibody-negative patients (22%). All mutations had consensus pathogenicity support by five algorithms. As in Europeans, the most common gene was HNF1A (MODY3), in 6 of 18 cases. Surprisingly, almost as frequent were diallelic mutations in WFS1, known to cause Wolfram syndrome but also described in nonsyndromic cases. Fasting C-peptide varied widely and was not predictive. Given the 27.4% autoantibody negativity in Chinese and 22% mutation rate, we estimate that ∼6% of Chinese with a clinical T1D diagnosis have monogenic diabetes. Our findings support universal sequencing of autoantibody-negative cases as standard of care in East Asian patients with a clinical T1D diagnosis. Nonsyndromic diabetes with WSF1 mutations is not rare in Chinese. Its response to alternative treatments should be investigated.

OBJECTIVE Type 1 diabetes (T1D) is a highly heritable disease with much lower incidence but more adult-onset cases in the Chinese population. Although genome-wide association studies (GWAS) have identified >60 T1D loci in Caucasians, less is known in Asians. RESEARCH DESIGN AND METHODS We performed the first two-stage GWAS of T1D using 2,596 autoantibody-positive T1D case subjects and 5,082 control subjects in a Chinese Han population and evaluated the associations between the identified T1D risk loci and age and fasting C-peptide levels at T1D diagnosis. RESULTS We observed a high genetic correlation between children/adolescents and adult T1D case subjects (rg = 0.87), as well as subgroups of autoantibody status (rg ≥ 0.90). We identified four T1D risk loci reaching genome-wide significance in the Chinese Han population, including two novel loci, rs4320356 near BTN3A1 (odds ratio [OR] 1.26, P = 2.70 × 10−8) and rs3802604 in GATA3 (OR 1.24, P = 2.06 × 10−8), and two previously reported loci, rs1770 in MHC (OR 4.28, P = 2.25 × 10−232) and rs705699 in SUOX (OR 1.46, P = 7.48 × 10−20). Further fine mapping in the MHC region revealed five independent variants, including another novel locus, HLA-C position 275 (omnibus P = 9.78 × 10−12), specific to the Chinese population. Based on the identified eight variants, we achieved an area under the curve value of 0.86 (95% CI 0.85–0.88). By building a genetic risk score (GRS) with these variants, we observed that the higher GRS were associated with an earlier age of T1D diagnosis (P = 9.08 × 10−11) and lower fasting C-peptide levels (P = 7.19 × 10−3) in individuals newly diagnosed with T1D. CONCLUSIONS Our results extend current knowledge on genetic contributions to T1D risk. Further investigations in different populations are needed for genetic heterogeneity and subsequent precision medicine.

CD4 Tregs are involved in the regulation of various autoimmune diseases but believed to be highly heterogeneous. Studies have indicated that Helios controls a distinct subset of functional Tregs. However, the immunological changes in circulating Helios+ and Helios− Tregs are not fully explored in type 1 diabetes (T1D). Here, we elucidated the differences in maturation status and immune regulatory phenotypes of Helios+ and Helios− Tregs and their correlations with monocyte subsets in T1D individuals. As CD25−/low FOXP3+ Tregs also represent a subset of functional Tregs, we defined Tregs as FOXP3+CD127−/low and examined circulating Helios+ and Helios− Treg subpopulations in 68 autoantibody-positive T1D individuals and 68 age-matched healthy controls. We found that expression of both FOXP3 and CTLA4 diminished in Helios− Tregs, while the proportion of CD25−/low Tregs increased in Helios+ Tregs of T1D individuals. Although the frequencies of neither Helios+ nor Helios− Tregs were affected by investigated T1D genetic risk loci, Helios+ Tregs correlated with age at T1D diagnosis negatively and disease duration positively. Moreover, the negative correlation between central and effector memory proportions of Helios+ Tregs in healthy controls was disrupted in T1D individuals. Finally, regulatory non-classical and intermediate monocytes also decreased in T1D individuals, and positive correlations between these regulatory monocytes and Helios+/Helios− Treg subsets in healthy controls disappeared in T1D individuals. In conclusion, we demonstrated the alternations in maturation status and immune phenotypes in Helios+ and Helios− Treg subsets and revealed the missing association between these Treg subsets and monocyte subsets in T1D individuals, which might point out another option for elucidating T1D mechanisms.

The critical role of IL-10–producing B cells (B10 cells) with a unique CD1dhiCD5+ phenotype in suppressing autoimmune responses and relieving inflammation has been demonstrated in several models of autoimmune diseases. However, the regulatory role of B10 cells in T cell–mediated autoimmune responses during the natural history of type 1 diabetes is unclear. In this study, we used the NOD mouse model of autoimmune diabetes to clarify the changes and potential mechanisms of B10 cells for disease. Compared with B10 cells present in the 4-wk-old normoglycemic NOD mice, the frequency of B10 cells was increased in the insulitis and diabetic NOD mice, with the highest proportion in the insulitis NOD mice. The changes in the relative number of B10 cells were most pronounced in the pancreas-draining lymph nodes. The pathogenic T cells, including Th1 and Th17 cells, remarkably increased. The assays in vitro showed that B10 cells in the NOD mice did not inhibit the proliferation of CD4+CD25− T cells. They also had no regulatory effect on IFN-γ and IL-4 secretion or on Foxp3 expression of T cells. B10 cells suppressed T cell–mediated autoimmune responses via an IL-10–dependent pathway. In contrast, B10 cells in the NOD mice exhibited a significant reduction in IL-10 production. In summary, a defect in the number and function of B10 cells may participate in the development and progression of type 1 diabetes.

CD4 Tregs are involved in the regulation of various autoimmune diseases but believed to be highly heterogeneous. Studies have indicated that Helios controls a distinct subset of functional Tregs. However, the immunological changes in circulating Helios+ and Helios− Tregs are not fully explored in type 1 diabetes (T1D). Here, we elucidated the differences in maturation status and immune regulatory phenotypes of Helios+ and Helios− Tregs and their correlations with monocyte subsets in T1D individuals. As CD25−/low FOXP3+ Tregs also represent a subset of functional Tregs, we defined Tregs as FOXP3+CD127−/low and examined circulating Helios+ and Helios− Treg subpopulations in 68 autoantibody-positive T1D individuals and 68 age-matched healthy controls. We found that expression of both FOXP3 and CTLA4 diminished in Helios− Tregs, while the proportion of CD25−/low Tregs increased in Helios+ Tregs of T1D individuals. Although the frequencies of neither Helios+ nor Helios− Tregs were affected by investigated T1D genetic risk loci, Helios+ Tregs correlated with age at T1D diagnosis negatively and disease duration positively. Moreover, the negative correlation between central and effector memory proportions of Helios+ Tregs in healthy controls was disrupted in T1D individuals. Finally, regulatory non-classical and intermediate monocytes also decreased in T1D individuals, and positive correlations between these regulatory monocytes and Helios+/Helios− Treg subsets in healthy controls disappeared in T1D individuals. In conclusion, we demonstrated the alternations in maturation status and immune phenotypes in Helios+ and Helios− Treg subsets and revealed the missing association between these Treg subsets and monocyte subsets in T1D individuals, which might point out another option for elucidating T1D mechanisms.

ObjectiveHyperinsulinemia and insulin resistance are co-existing characteristics of type 2 diabetes, whereas the molecular mechanism underlying this deleterious cycle remains elusive. The temporal transcriptomic landscape of core organs responsible for insulin secretion (islets) and insulin action (liver) could provide new insights.MethodsThe longitudinal profiling of glucose metabolism, insulin sensitivity, islet architecture and secretion were conducted in C57BL/6N mice fed a high-fat diet (HFD) or chow diet for 24 weeks. RNA-sequencing of islets and liver were performed once every 4 weeks. Weighted gene co-expression network analysis and Ingenuity Pathway Analysis were applied to construct networks and evaluate co-ordinated molecular interactions between islets and liver.ResultsMice exhibited progressively deteriorated glucose homeostasis with hyperinsulinemia but impaired first-phase insulin secretion after 4 weeks on HFD. Insulin, glucagon and somatostatin secretion in response to glucose with or without palmitate gradually deteriorated from dysregulation to failure. Systemic insulin resistance developed over 24 weeks with variable time course in tissue-specific insulin action. Our transcriptomic datasets outlined the impact of HFD on dynamics of islet and liver molecular network at different stages. Correlation analyses revealed that both organs jointly programmed β-cell compensatory adaption via cell proliferation at early phase and irreversible islet dysfunction by inappropriate immune response at later stage. Alternations of T cell subpopulations validated the participation of adaptive immune response through priming and amplification phases in diabetic progression.ConclusionOur data provide a comprehensive landscape of crosstalk between islets and liver in diet-induced diabetes, elucidating the development of islet dysfunction and insulin resistance.HighlightsDiet-induced diabetes is featured by transition from islet dysfunction to failureInsulin resistance develops with variable time course in different tissuesDynamics of islet and liver molecular network interplay at different stagesCell proliferation and improper immune reaction mediated interorgan crosstalkAdaptive immune response participated via priming and amplification phases

CD4 Tregs are involved in the regulation of various autoimmune diseases, but believed to be highly heterogeneous. Studies have indicated that Helios controls a distinct subset of functional Tregs. However, the immunological changes in circulating Helios+ and Helios- Tregs and contributing factors for these two Treg subsets are not fully understood in type 1 diabetes (T1D). Here, we elucidated the differences in maturation status and immune regulatory phenotypes of Helios+ and Helios- Tregs and their correlations with monocyte subsets in T1D individuals. As CD25-/low Foxp3+ Tregs also represent a subset of functional Tregs, we defined Tregs as Foxp3+CD127-/low and examined circulating Helios+ and Helios- Treg subpopulations in 68 islet-specific autoantibody-positive T1D individuals and 68 age-matched autoantibody-negative healthy controls. We found that Foxp3 and CTLA4 expression diminished in Helios- Tregs, while the proportion of CD25-/low Tregs increased in Helios+ Tregs of T1D individuals. Although the frequencies of neither Helios+ nor Helios- Tregs were affected by T1D genetic risk loci, Helios+ Tregs correlated with age at T1D diagnosis negatively and disease duration positively. Moreover, for Helios+ Tregs identified by CD45RA/CCR7 expression, the negative correlation between central and effector memory proportions in healthy controls disrupted in T1D individuals. Finally, regulatory non-classical and intermediate monocytes also decreased in T1D individuals, and positive correlations between regulatory monocytes and Helios+/Helios- Treg subsets in healthy controls disappeared in T1D individuals. These findings shed new light on the immunological changes on Helios+ and Helios- Treg subsets and their correlations with other regulatory immune cells underlying T1D, which may help stratify patients for clinical trials and for monitoring immunotherapy outcomes. Funding Statement: This study was supported by grants from the National Natural Science Foundation of China (81670715), Jiangsu Province Youth Medical Talents Project (QNRC2016584), the Natural Science Foundation of Jiangsu Province (BK2012486), Jiangsu Government Scholarship for Overseas Studies (JS-2013-260), and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD). Declaration of Interests: The authors declare that there is no duality of interest associated with this manuscript. Ethics Approval Statement: The study was approved by the Ethics Committee from the First Affiliated Hospital of Nanjing Medical University and conducted according to the principles of the Declaration of Helsinki.

Induction of antigen-specific immunological tolerance may provide an attractive immunotherapy in the NOD mouse model but the conditions that lead to the successful translation to human type 1 diabetes are limited. In this study, we covalently linked 500 nm carboxylated polystyrene beads (PSB) with a mixture of immunodominant HLA-A*02:01-restricted epitopes (peptides-PSB) that may have high clinical relevance in humans as they promote immune tolerance; we then investigated the effect of the nanoparticle–peptide complexes on T cell tolerance. PSB-coupled mixtures of HLA-A*02:01-restricted epitopes were administered to HHD II mice via intravenous injection. The effects on delaying the course of the disease were verified in NOD.β2m null HHD mice. The diabetogenic HLA-A*02:01-restricted cytotoxic lymphocyte (CTL) responses to treatment with peptides-PSB were validated in individuals with type 1 diabetes. We showed that peptides-PSB could induce antigen-specific tolerance in HHD II mice. The protective immunological mechanisms were mediated through the function of CD4+CD25+ regulatory T cells, suppressive T cell activation and T cell anergy. Furthermore, the peptides-PSB induced an activation and accumulation of regulatory T cells and CD11c+ dendritic cells through a rapid production of CD169+ macrophage-derived C-C motif chemokine 22 (CCL22). Peptides-PSB also prevented diabetes in ‘humanised’ NOD.β2m null HHD mice and suppressed pathogenic CTL responses in people with type 1 diabetes. Our findings demonstrate for the first time the potential for using multipeptide-PSB complexes to induce T cell tolerance and halt the autoimmune process. These findings represent a promising platform for an antigen-specific tolerance strategy in type 1 diabetes and highlight a mechanism through which metallophilic macrophages mediate the early cell–cell interactions required for peptides-PSB-induced immune tolerance.

Recent meta-genome-wide association studies identified several genetic variants associated with beta-cell function in type 1 diabetes (T1D). The aim of this study was to investigate the associations between these variants and T1D risk, C-peptide levels, islet-specific autoantibodies, and lipid levels in Chinese Han population.A total of 1005 unrelated autoantibody-positive T1D cases and 1417 healthy controls were included, which were genotyped for rs559047, rs9260151, and rs3135002. T1D individuals were measured for both C-peptide and lipid levels. Logistic regression models were used to examine these associations.We found that rs3135002 A allele showed a genome-wide significant association with T1D risk (OR = 0.22, 95% CI = 0.17-0.30; P = 7.49 × 10Our results indicate that there are both similarities and differences for the associations of genetic variants among T1D development, progression, and related autoimmunity, metabolic traits.

Liver secretes proliferative factors participating compensatory hyperplasia of islets during obesity and insulin resistance. Extracellular vesicles (EVs) mediate intercellular communication by delivering inner factors to recipient cells. This study explored the biological effects of hepatocellular EVs on islet β cells during obesity. Compared with standard chow diet (CD), hepatocellular EVs derived from high-fat diet (HFD) induced obese mice promoted proliferation of β cell line-MIN6 cells, but didn't influence their insulin secretion. Microarray analysis found 13 miRNAs with significantly differential expression in hepatocellular EVs between HFD with CD group. Meanwhile, RNA-sequencing detected 80 genes with significantly differential expression in MIN6 cells treated with HFD and CD hepatocellular EVs respectively. Six miRNAs and 11 potential target genes were pre-screened by synthesizing TargetScan prediction and RNA-sequencing results. After miRNA mimic transfection and testing the expressions of target genes and cell vitality, miR-7218-5p was verified to affect MIN6 cell proliferation through targeting CD74 gene. SiRNA transfection and dual luciferase reporter assay further confirmed the binding and regulation of miRNA-7218-5p on CD74. These findings suggest HFD induced obesity could change miRNA profiles in hepatocellular EVs, which modulate expression of multiple genes and proliferation of MIN6 cells and maybe mediate compensatory hyperplasia of islets.

It is estimated that ∼1% of European ancestry patients clinically diagnosed with type 1 diabetes (T1D) actually have monogenic forms of the disease. Because of the much lower incidence of true T1D in East Asians, we hypothesized that the percentage would be much higher. To test this, we sequenced the exome of 82 Chinese Han patients clinically diagnosed with T1D but negative for three autoantibodies. Analysis focused on established or proposed monogenic diabetes genes. We found credible mutations in 18 of the 82 autoantibody-negative patients (22%). All mutations had consensus pathogenicity support by five algorithms. As in Europeans, the most common gene was

ObjectiveImpaired follicular regulatory T (Tfr) cells enhance T follicular helper cells activity, resulting in the expansion of autoreactive B cells and autoantibody production. However, the role of Tfr cells in the pathogenesis of type 1 diabetes (T1D) is unclear.DesignWe evaluated the expression and changes in function of circulating Tfr cells by studying patients with T1D alongside those with type 2 diabetes (T2D), first-degree relatives of T1D patients, and healthy controls. We also investigated the effects of Tfr cells on disease development in nonobese diabetic (NOD) mice and in an adoptive transfer model.ResultsTfr cells were significantly decreased in both patient groups. However, they showed different correlations with fasting C-peptide (C-P) and the area under the curve of blood C-P in patients with T1D and T2D. The frequency of Tfr cells was associated with the number of positive autoantibodies and the titer of glutamic acid decarboxylase autoantibody in T1D patients. Furthermore, Tfr cells decreased significantly after 1 year of follow-up. We also observed Tfr cells in four T1D patients treated with rituximab. After rituximab therapy, the frequency of C-X-C motif chemokine receptor 5 (CXCR5)+ programmed death 1+ Tfr cells was decreased and of CXCR5+ inducible costimulator+ Tfr cells was increased in three patients. We also found that Tfr cells were associated with the development of diabetes in NOD mice and an adoptive transfer model.ConclusionsTfr cell deficiency could be involved in the pathogenesis of T1D. Therapy with Tfr cells has potential value for T1D. Modulation of these cells may enhance protective immunity to inhibit autoimmune diabetes.

Objective: To investigate the association between polymorphisms in PTPN2 (rs1893217 and rs478582) and type 1 diabetes (T1D) risk with different diagnosed age, as well as related clinical characteristics in Chinese Han population. Methods: A total of 2270 Chinese Han individuals (1023 T1D patients and 1247 healthy controls) were genotyped for rs1893217 and rs478582. And 306 newly diagnosed T1D patients were measured for C-peptide levels based on a standard mixed-meal tolerance test. In addition, 40 healthy controls were analyzed for different T cell subsets by multi-color flow cytometry. Results: Neither rs1893217 nor rs478582 showed any association with T1D risk under an additive model. Stratified analysis for T1D diagnosed age revealed that rs1893217, but not rs478582, was significantly associated with T1D patients diagnosed age ≤18 (OR =0.80, 95% CI: 0.67–0.97, p = 0.02). For those diagnosed age >18, neither of them showed any association. We also found that rs1893217 had a higher positive rate of ZnT8A (CC vs. TT carrier, OR = 2.07, 95% CI: 1.07–4.03, p = 0.026) and IA-2A (CT vs. TT carrier, OR = 1.36, 95% CI: 1.02–1.80, p = 0.038). Furthermore, for rs478582, compared with TT, healthy individuals carrying CC/CT carriers had significantly lower frequency and Helios expression of naive Treg subsets (p = 0.049 and 0.048 respectively), but not secreting or activating Treg subsets. In addition, we did not find any association between these two polymorphisms and residual β-cell function in newly diagnosed T1D patients. Conclusions: Our results suggest that rs1893217 may increase the risk of early-onset T1D and affect humoral immunity, while rs478582 may affect Treg subsets.

Summary To investigate the molecular mechanisms underlying islet dysfunction and insulin resistance in diet-induced diabetes, we conducted temporal RNA sequencing of tissues responsible for insulin secretion (islets) and action (liver) every 4 weeks in mice on high-fat (HFD) or chow diet for 24 weeks, linking to longitudinal profile of metabolic characteristics. The diverse responses of α, β, and δ cells to glucose and palmitate indicated HFD-induced dynamic deterioration of islet function from dysregulation to failure. Insulin resistance developed with variable time course in different tissues. Weighted gene co-expression network analysis and Ingenuity Pathway Analysis implicated islets and liver jointly programmed β-cell compensatory adaption via cell proliferation at early phase and irreversible islet dysfunction by inappropriate immune response at later stage, and identified interconnected molecules including growth differentiation factor 15. Frequencies of T cell subpopulation showed an early decrement in Tregs followed by increases in Th1 and Th17 cells during progression to diabetes., Graphical abstract, Highlights • Diet-induced diabetes is featured by transition from islet dysfunction to failure • Insulin resistance develops with variable time course in different tissues • Dynamics of islet and liver molecular network interplay at different stages • T-cell-mediated immune response participates via priming and amplification phases, Animal Physiology ; Diabetology ; Transcriptomics

Objective ZnT8-specific CD8+ T cells in human type 1 diabetes (T1D) have been reported recently, although the results from different laboratories are inconsistent. We aimed to characterize these ZnT8 specific CD8+ T cells and validate assays to screen peptide libraries. Methods We screened HLA-A2-restricted T cell candidate peptides of ZnT8 with different methods including computer algorithms, MHC-peptide binding and dissociation assays in T2 cell line, identification in HLA-A2 transgenic (Tg) mice and in vivo CTL assays. Then ELISpot assay was used to measure peptide-reactive T cell responses in 49 HLA-A2-restricted T1D patients. Results We demonstrated that ZnT8 107–116(115) , ZnT8 110–118 , and ZnT8 177–186 were novel HLA-A*0201-restricted CTL epitopes in T1D patients. ZnT8 107–116(115) , ZnT8 115–123 , ZnT8 153–161 , ZnT8 177–186 and ZnT8 291–300 represent potentially major biomarkers for T1D. T cell responses against these epitopes showed different distributions between recently diagnosed and long-standing patients. Furthermore, they displayed discriminating performance among different ethnicities. We also compared the performance of the epitope identification strategies used herein. The epitopes which exhibited strong immunogenicity in HLA-A2 Tg mice were also well recognized by T1D patients. Conclusions The differences in autoimmune T cell responses among T1D individuals may open new avenues toward T1D prediction and prevention. It also provides efficient strategies for immune intervention.

To investigate whether CTLA-4 +49 G/A (rs231775), a tagSNP in Asian, is a functional T1D SNP, we genotyped this SNP with 1035 T1D patients and 2575 controls in Chinese Han population. And 1280 controls measured insulin release and sensitivity based on an oral glucose tolerance test; 283 newly diagnosed T1D patients assayed C-peptide level based on a mixed-meal tolerance test. 31 controls were analyzed for different T cell subsets by multi-color flow cytometry. Under additive model, we found that CTLA-4 +49 G/A was significantly associated with T1D (P = 2.82E-04, OR = 1.25, 95% CI: 1.12–1.41), which was further confirmed by meta-analysis (P = 1.19E-08, OR = 1.65, 95% CI: 1.38–1.96) in Chinese Han population. Although we did not find any association between this SNP and beta-cell function in either healthy individuals or newly diagnosed T1D patients, healthy individuals carrying GG/GA genotypes had lower CTLA-4 expression in naïve or activated CD4 Treg subsets (P = 0.0046 and 0.0317 respectively). A higher positive rate of IA-2A was observed among T1D patients with GG genotype compared with AA (OR = 0.51, 95% CI: 0.30–0.84, p = 0.008). Collectively, CTLA-4 +49 G/A reached a GWAS significant association with T1D risk in Chinese Han population, affects CTLA-4 expression in Treg subsets and subsequently humoral immunity in T1D patients.

Type 1 diabetes (T1D) is a highly heritable autoimmune disease. Although more than 50 non-HLA risk loci have been identified, the strongest associations were observed in HLA regions in Caucasian populations. The aim of this study is to identify T1D risk HLA loci in Chinese Han population and explore the risk prediction models based on these loci. A two-stage genome-wide association study (GWAS) of T1D (at least one autoantibody positive) was performed in Chinese Han population, the GWAS scan was conducted by the Illumina Human OmniZhongHua platform and included 1,045 T1D cases and 1,3controls, and the replication included 1,378 cases and 3,774 controls. Promising associations were further validated by combining with the data from the Wellcome Trust Case Control Consortium (WTCCC). Association analyses for T1D used logistic regression models assuming additive effects. Results from different stages were combined with fixed effects model in meta-analysis. In the GWAS scan stage, we identified 18 distinct genomic regions with P-values Disclosure K. Xu: None. Y. Chen: None. Y. Gu: None. M. Zhu: None. M. Zhang: None. M. Sun: None. X. Xu: None. H. Hsu: None. H. Chen: None. Y. Shi: None. Y. Cai: None. H. Dai: None. S. Zheng: None. X. Zheng: None. H. Zhou: None. L. Yu: None. Z. Hu: None. Z. Zhou: None. J. Weng: None. H. Shen: None. T. Yang: None.

To investigate whether PDCD1 gene polymorphisms are functional, and their associations with T1D risk and related clinical characteristics. A total of 3060 Chinese Han individuals (1019 T1D patients and 2041 healthy controls) were genotyped for 4 tag single nucleotide polymorphisms (SNPs) within the PDCD1 region (rs2227982, rs7421861, rs10204525, and rs6710479) and another most studied synonymous SNP, rs2227981. In addition, 251 healthy individuals underwent an oral glucose tolerance test (OGTT); measures of insulin release and sensitivity were estimated from insulinogenic, BIGTT, Matsuda. Further, we performed in silico bioinformatics analysis to explore potential functional annotation of the investigated SNPs in PDCD1 gene. Both rs2227982 and rs2227981 polymorphisms were associated with T1D risk in Chinese Han population under additive model (OR = 0.84, 95% CI 0.75–0.93 and OR = 1.23, 95% CI 1.08–1.40, respectively), but not the other three SNPs in PDCD1 gene. Our meta-analysis revealed that rs2227982 and rs2227981 polymorphisms also have significant associations with T1D risk in East Asians (OR = 0.82, 95% CI 0.74–0.90 and OR = 1.23, 95% CI 1.12–1.36, respectively), but not Europeans. And the T allele of rs2227982 polymorphism is associated with increased 30 min post OGTT glucose level (P = 0.023) and 120 min post OGTT insulin level (P = 0.033). Furthermore, the genetic and regulatory architecture suggested all the 5 investigated SNPs in PDCD1 are putatively functional. Both rs2227982 and rs2227981 polymorphisms were associated with T1D risk in East Asians, and rs2227982 also had a significant association with glycemic traits, which suggested PDCD1 gene polymorphisms might participate in facilitating T1D risk.

In this article, we conducted an updated meta-analysis with trial sequential analysis (TSA) to refine the associations between three common single nucleotide polymorphisms (SNPs) in the CTLA-4 gene (+49A/G, CT60, and -318C/T) and Hashimoto's thyroiditis (HT).Statistical association analyses were performed using four genetic models, including the allelic, codominant, dominant, and recessive models with the Revman 5.3, Stata 14.0, and TSA 0.9 software. For quality evaluation, the Newcastle-Ottawa Scale was used.Our meta-analysis included 29 independent studies with low risk of bias that involved 3614 cases and 8839 controls. The pooled results indicated a significant association between the +49A/G polymorphism and an increased risk of HT in all four genetic models. Furthermore, the TSA demonstrated that the evidence of this association was robust and credible. Subgroup analysis revealed a significantly higher risk of HT in Asians compared with Caucasians associated with the +49A/G polymorphism. Surprisingly, in contrast to the results with adults, we did not find any significant association when analyzing the pediatric subgroup. For the CT60 polymorphism, a significant association with risk of HT was detected overall, and subgroup analysis revealed that this association was significant in the Asian subgroup, but not in the Caucasian subgroup. No statistically significant associations were detected in any of the investigated genetic models for the -318C/T polymorphism. However, the results of the TSA suggested that the sample sizes used for the CTLA-4 CT60 and -318C/T SNPs were insufficient.Our meta-analysis showed significant associations between the risk of HT and both the +49A/G and CT60 polymorphisms, but not the -318C/T polymorphism. In addition, the TSA results indicated that CTLA-4 +49A/G should be considered as a biomarker for HT, whereas both the CT60 and -318C/T SNPs warrant confirmation by further studies.

Single nucleotide polymorphisms (SNPs) in the interleukin 2 receptor alpha (IL2RA) gene have been suggested to be associated with type 1 diabetes (T1D) susceptibility. However, the results from individual studies are inconsistent. To explore the association of IL2RA polymorphisms with T1D, including rs11594656, rs2104286, rs3118470, rs41295061 and rs706778, a meta-analysis involving 10 independent studies with 19 outcomes was conducted: five studies with a total of 10,572 cases and 12,956 controls were analysed for rs11594656 with T1D risk, three studies with 7300 cases and 8331 controls for rs2104286, three studies with 3880 cases and 5409 controls for rs3118470, five studies with 11,253 cases and 13,834 controls for rs41295061 and three studies with 1896 cases and 1709 controls for rs706778 respectively. Using minor allelic comparison, the five investigated SNPs were all observed to have a significant association with T1D: For rs11594656, fixed effect model (FEM) odds ratio (OR) 0.87, 95% confidence interval (CI) 0.83, 0.91; rs2104286, FEM OR 0.81, 95% CI 0.77, 0.85; rs3118470, FEM OR 1.23, 95% CI 1.16, 1.31; rs41295061, random effect model (REM) OR 0.67, 95% CI 0.60, 0.76 and rs706778 FEM OR 1.20, 95% CI 1.08, 1.33. Similar results were obtained when all the included studies were calculated by a REM. Our meta-analysis suggests that all five SNPs in the IL2RA gene are risk factors for T1D risk, and rs11594656, rs2104286 and rs41295061 are the most associated SNPs in the populations investigated. This conclusion warrants confirmation by further studies.

The aim of this study was to investigate physiological factors that affect serum insulin levels and to establish insulin reference intervals for healthy Chinese Han adults. A total of 4401 subjects with normal glucose tolerance (NGT) were screened from 10,027 individuals in an epidemiological study. Based on the exclusion criteria, 2414 apparently healthy adults (healthy) were selected as reference individuals. Serum insulin levels of the reference individuals were measured at fasting, 30 min and 120 min after oral glucose tolerance test (OGTT). Significant correlations were found between serum insulin levels and physiological factors in healthy subjects, including body mass index (BMI), weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), etc. (p0.05). No increase or decrease was found in age-dependent insulin levels by ANOVA (p0.05). There was also no substantial difference in fasting serum insulin levels between males and females (p0.05). However, we detected notable differences in serum insulin levels between males and females at 30 min (p0.01), which became more pronounced at 120 min (p0.001). According to our data, BMI/gender-related insulin reference intervals were defined by calculating 2.5th and 97.5th percentiles. The insulin reference intervals, determined after assessing the relationship between physiological factors and serum insulin levels in Chinese adults, will provide valuable information for physicians in their interpretation of insulin levels.

Induction of antigen-specific immunological tolerance may provide an attractive immunotherapy in the NOD mouse model but the conditions that lead to the successful translation to human type 1 diabetes are limited. In this study, we covalently linked 500 nm carboxylated polystyrene beads (PSB) with a mixture of immunodominant HLA-A*02:01-restricted epitopes (peptides-PSB) that may have high clinical relevance in humans as they promote immune tolerance; we then investigated the effect of the nanoparticle-peptide complexes on T cell tolerance.PSB-coupled mixtures of HLA-A*02:01-restricted epitopes were administered to HHD II mice via intravenous injection. The effects on delaying the course of the disease were verified in NOD.β2mWe showed that peptides-PSB could induce antigen-specific tolerance in HHD II mice. The protective immunological mechanisms were mediated through the function of CD4Our findings demonstrate for the first time the potential for using multipeptide-PSB complexes to induce T cell tolerance and halt the autoimmune process. These findings represent a promising platform for an antigen-specific tolerance strategy in type 1 diabetes and highlight a mechanism through which metallophilic macrophages mediate the early cell-cell interactions required for peptides-PSB-induced immune tolerance.

Identification of cognate peptides recognized by human leucocyte antigen (HLA)/T cell receptor (TCR) complex provides insight into the pathogenic process of type 1 diabetes (T1D). We hypothesize that HLA-binding assays alone are inadequate metrics for the affinity of peptides. Zinc transporter-8 (ZnT8) has emerged in recent years as a novel, major, human autoantigen. Therefore, we aim to identify the HLA-A2-restricted ZnT8 epitopes using both binding and dissociation assays. HLA class I peptide affinity algorithms were used to predict candidate ZnT8 peptides that bind to HLA-A2. We analyzed 15 reported epitopes of seven β-cell candidate autoantigens and eight predicted candidate ZnT8 peptides using binding and dissociation assays. Using IFN-γ ELISpot assay, we tested peripheral blood mononuclear cells (PBMCs) from recent-onset T1D patients and healthy controls for reactivity to seven reported epitopes and eight candidate ZnT8 peptides directly ex vivo. We found five of seven recently reported epitopes in Chinese T1D patients. Of the eight predicted ZnT8 peptides, ZnT8(153-161) had a strong binding affinity and the lowest dissociation rate to HLA-A*0201. We identified it as a novel HLA-A*0201-restricted T-cell epitope in three of eight T1D patients. We conclude that ZnT8(153-161) is a novel HLA-A*0201-restricted T-cell epitope. We did not observe a significant correlation (P = 0.3, R = - 0.5) between cytotoxic T cell (CTL) response and peptide/HLA*0201 complex stability. However, selection of peptides based on affinity and their dissociation rate may be helpful for the identification of candidate CTL epitopes. Thus, we can minimize the number of experiments for the identification of T-cell epitopes from interesting antigens.

The evaluation of susceptibility loci is an important addition to the current predictive and screening models in type 1 diabetes of Chinese Han population. Therefore, the aim of this study is to provide evidence for the association between type 1 diabetes and two polymorphisms (rs3747517, rs1990760) from interferon induced with helicase C domain 1 (IFIH1). Here, 464 Type 1 diabetespatients and 465 control subjects were genotyped for these 2 polymorphisms. The results indicated that the allelic frequencies of rs3747517 revealed a strong association with type 1 diabetes risk (P < 0.001); yet, no significant association was observed on rs1990760(P = 0.76). Furthermore, IFIH1 rs3747517 polymorphism had no influence on the positive rates of pancreatic auto-antibodies, and both of the polymorphisms had no interaction with HLA class I-linked risk or phenotypes. In conclusion, IFIH1 rs3747517, but not rs1990760 polymorphism, plays an important role in type 1 diabetes risk in Chinese Han population.

Aims To investigate the association of solute carrier family 30 member 8 (SLC30A8) rs13266634 C/T polymorphism with type 2 diabetes (T2DM), impaired glucose tolerance (IGT), and type 1 diabetes (T1DM). Methods We searched all the publications about the association between SLC30A8 and diabetes from PubMed, and evaluated the association between SLC30A8 rs13266634 C/T polymorphism and T2DM, IGT and T1DM, respectively, by meta-analysis of all the validated studies. Allelic and genotypic comparisons between cases and controls were evaluated. Results Thirty six studies were included in the meta-analysis: 31 studies were analysed for rs13266634 C/T polymorphism with T2DM, 3 studies with IGT and 4 studies with T1DM. The pooled odds ratios (ORs) for allelic and genotypic comparisons (including additive model, co-dominant model, dominant model and recessive model) showed that rs13266634 C/T polymorphism was significantly associated with increased T2DM risk: OR=1.15, 95% confidence interval (CI)=1.13–1.17, P P heterogeneity =0.041, OR=1.34, 95% CI=1.26–1.41, P P heterogeneity =0.908, OR=1.20, 95% CI=1.16–1.24, P P heterogeneity =0.699, and OR=1.23, 95% CI=1.17–1.30, P P heterogeneity =0.801, respectively. In subgroup analyses, we found that rs13266634 C/T polymorphism was associated with T2DM risk both in Asian and European subgroup ( P P >0.05). And the pooled odds ratio (OR) for allelic frequency comparison showed that rs13266634 C/T polymorphism was also significantly associated with IGT: OR=1.15, 95% CI=1.06–1.26, P P heterogeneity =0.364. Meanwhile, our meta-analysis did not suggest that rs13266634 C/T polymorphism was associated with T1DM risk ( P >0.05): OR=1.02, 95% CI=0.98–1.06, P =0.328, P heterogeneity =0.488 for allelic frequency comparison. Conclusions Our meta-analysis results revealed the significant association between rs13266634 C/T polymorphism and T2DM and IGT, but did not support the association between this polymorphism and T1DM.

There is a widespread interest in defining factors and mechanisms that stimulate proliferation of pancreatic islet β-cells. Pregnancy is a special period when the pancreatic islet displays a highly reproducible physiological proliferation. However, the molecular mechanism of β-cell proliferation during pregnancy is unclear. Here, we used cDNA expression array to explore gene expression profiles of islet at various stages of pregnancy in rats. Differentially expressed genes related to islet proliferation were screened by bioinformatics methods, and further verified by real-time PCR, RT-PCR, and Western blotting. Compared with control group, expressions of hundreds of genes were changed during pregnancy. The differentially expressed genes related to islet proliferation were mainly distributed in three groups: genes involved in transcription regulator activity, genes involved in apoptosis or tumor, and genes for Wnt signaling pathway. Among these genes, expressions of Nupr1, Atf3, Btg2, β-catenin, and c-Myc mRNA were up-regulated during pregnancy. A prominent expression of Nupr1 and Atf3 protein was observed in islets on day 10.5 of pregnancy, i.e., with earlier time phases than proliferation peak. Moreover, we found that prolactin (PRL) can increase the proliferation of β-cell in vitro, which is accompanied by up-regulation of Atf3 and Nupr1, indicating that they may play a crucial role in PRL-induced pancreatic β-cell growth. In conclusion, our results suggest that the transcription factor Nupr1, Atf3, and Wnt pathway may play an important role in adaptive proliferation of pancreatic islets during pregnancy in rats.

During pregnancy, the pancreatic islets undergo major structural and functional changes in response to increased peripheral resistance to insulin. In this study, we investigated the adaptive changes of the pancreatic islet beta-cell mass during pregnancy in rats, and explored profiles of islet gene expression at various stages of pregnancy. Some differentially expressed genes were verified by RT-PCR and Real-time PCR. Our results showed that compared with the non-pregnant control group, insulin synthesis, glucose-stimulated insulin secretion, islet beta-cell proliferation, and islet size were all increased in pregnant rats. The study also demonstrated that expression of several-hundred islet genes were changed during pregnancy, especially at day 14.5. The differentially expressed genes identified were distributed into eight main categories according to their biological functions: (1) genes involved in apoptosis or tumor; (2) genes related to binding; (3) genes involved in metabolism; (4) genes related to cell cycle; (5) genes for signal transducer activity; (6) genes related to structural molecule activity; (7) genes involved in transcription regulator activity; (8) genes for transporter activity. Among these genes, regenerating islet-derived 3 alpha (Reg3a) was remarkably increased during pregnancy. We hypothesize that differentially expressed genes may play an important role in adaptation of pancreatic islets during pregnancy in rats. In addition, the markedly increased expression of gene Reg3a is probably related to islet regeneration.

Chronic low-grade inflammation characterized by adipose tissue macrophage accumulation and abnormal cytokine production is a key feature of obesity and type 2 diabetes. Adipose-tissue-derived monocyte chemoattractant protein (MCP)-1, induced by cytokines, has been shown to play an essential role in the early events during macrophage infiltration into adipose tissue. In this study we investigated the effects of resveratrol upon both tumor necrosis factor (TNF)-a-induced MCP-1 gene expression and its underlying signaling pathways in 3T3-L1 adipoctyes. Resveratrol was found to inhibit TNF-a-induced MCP-1 secretion and gene transcription, as well as promoter activity, which based on down-regulation of TNF-a-induced MCP-1 transcription. Nuclear factor (NF)-jB was determined to play a major role in the TNF-a-induced MCP-1 expression. Further analysis showed that resveratrol inhibited DNA binding activity of the NF-jB complex and subsequently suppressed NF-jB transcriptional activity in TNF-a-stimulated cells. Finally, the inhibition of MCP-1 may represent a novel mechanism of resveratrol in preventing obesity-related pathologies. 2008 Elsevier Inc. All rights reserved.

Aim: To investigate the activity and expression of neutral ceramidase (N-CDase) in the insulin-secreting cell line INS-1 and its role in the cellular response to cytokines. Methods: HPLC, Western blotting, and quantitative real-time PCR were performed to detect the activity and expression of N-CDase in INS-1 cells treated with a cytokine mixture (5 ng/mL interleukin-1β, 10 ng/mL TNF-α, and 50 ng/mL interferon-γ). The expression and activity of N-CDase in the INS-1 cells were specifically inhibited using N-CDase-siRNA transfection. Annexin V-fluorescein-isothiocyanate/propidium iodide flow cytometry was used to assess apoptosis in the INS-1 cells. Results: The INS-1 cells exhibited some basal N-CDase activity, and cytokines induced a time-dependent delay in the activation of N-CDase. As a result, the activation of N-CDase was first detectable at 8 h after stimulation. It peaked at 16 h and remained elevated at 24 h. Cytokines also upregulated the mRNA and protein expression of N-CDase in the INS-1 cells. Furthermore, when N-CDase activity was inhibited by RNA interference, cytokine-induced apoptosis in the INS-1 cells was markedly increased. Conclusion: The N-CDase pathway is active in INS-1 cells, and the chronic activation of N-CDase is involved in the pathological response of β-cells to cytokines, potentially providing protection against cytokine toxicity.

FTO (Fat mass and obesity-associated) is associated with increased risk of obesity and type 2 diabetes incurrence. Pancreas islet β cells dysfunction and insulin resistance are major causes of type 2 diabetes. However, whether FTO plays an important functional role in pancreatic β cells as well as the related molecular mechanism is still unclear. In the present study, the tissue expression profile of FTO was firstly determined using quantitative PCR and western blot. FTO is widely expressed in various tissues and presented with relative high expression in pancreas tissue, especially in endocrine pancreas. FTO overexpression in MIN6 cells achieved by lentivirus delivery significantly inhibits insulin secretion in the presence of glucose stimulus as well as KCl. FTO silence has no effect on insulin secretion of MIN6 cells. However, FTO overexpression doesn't affect the transcription of insulin gene. Furthermore, reactive oxygen species (ROS) production and NF-κB activation are significantly promoted by FTO overexpression. Inhibition of intracellular ROS production by N-acetyl-L-cysteine (NAC) can alleviate NF-κB activation and restore the insulin secretion mediated by FTO overexpression. A whole transcript-microarray is employed to analyze the differential gene expression mediated by FTO overexpression. The genes which are modulated by FTO are involved in many important biological pathways such as G-protein coupled receptor signaling and NF-κB signaling. Therefore, our study indicates that FTO may contribute to pancreas islet β cells dysfunction and the inhibition of FTO activity is a potential target for the treatment of diabetes.