Effect of fenofibrate on residual beta cell function in adults and adolescents with newly diagnosed type 1 diabetes: a randomised clinical trial.

AIMS/HYPOTHESIS: Fenofibrate, a peroxisome proliferator-activated receptor alpha agonist, shows some promise in alleviating beta cell stress and preserving beta cell function in preclinical studies of type 1 diabetes. The aim of this phase 2, placebo-controlled, double-blinded, randomised clinical trial was to investigate the efficacy and safety of fenofibrate in adults and adolescents with newly diagnosed type 1 diabetes. METHODS: We enrolled 58 individuals (aged 16 to 40 years old) with newly diagnosed type 1 diabetes and randomised them to daily oral treatment with fenofibrate 160 mg or placebo for 52 weeks (in a block design with a block size of 4, assigned in a 1:1 ratio). Our primary outcome was change in beta cell function after 52 weeks of treatment, assessed by AUC for C-peptide levels following a 2 h mixed-meal tolerance test. Secondary outcomes included glycaemic control (assessed by HbA1c and continuous glucose monitoring), daily insulin use, and proinsulin/C-peptide (PI/C) ratio as a marker of beta cell stress. We assessed outcome measures before and after 4, 12, 26 and 52 weeks of treatment. Blinding was maintained for participants, their healthcare providers and all staff involved in handling outcome samples and assessment. RESULTS: The statistical analyses for the primary outcome included 56 participants (n=27 in the fenofibrate group, after two withdrawals, and n=29 in the placebo group). We found no significant differences between the groups in either 2 h C-peptide levels (mean difference of 0.08 nmol/l [95% CI -0.05, 0.23]), insulin use or glycaemic control after 52 weeks of treatment. On the contrary, the fenofibrate group showed a higher PI/C ratio at week 52 compared with placebo (mean difference of 0.024 [95% CI 0.000, 0.048], p<0.05). Blood lipidome analysis revealed that fenofibrate repressed pathways involved in sphingolipid metabolism and signalling at week 52 compared with placebo. The 52 week intervention evoked few adverse events and no serious adverse events. Follow-up in vitro experiments in human pancreatic islets demonstrated a stress-inducing effect of fenofibrate. CONCLUSIONS/INTERPRETATION: Contrary to the beneficial effects of fenofibrate found in preclinical studies, this longitudinal, randomised, placebo-controlled trial does not support the use of fenofibrate for preserving beta cell function in individuals with newly diagnosed type 1 diabetes. TRIAL REGISTRATION: EudraCT number: 2019-004434-41 FUNDING: This study was funded by the Sehested Hansens Foundation.

Liraglutide enhances insulin secretion and prolongs the remission period in adults with newly diagnosed type 1 diabetes (the NewLira study): A randomized, double-blind, placebo-controlled trial.

AIM: To test the effect of the glucagon-like peptide-1 receptor agonist, liraglutide, on residual beta-cell function in adults with newly diagnosed type 1 diabetes. MATERIALS AND METHODS: In a multicentre, double-blind, parallel-group trial, adults with newly diagnosed type 1 diabetes and stimulated C-peptide of more than 0.2 nmol/L were randomized (1:1) to 1.8-mg liraglutide (Victoza) or placebo once daily for 52 weeks with 6 weeks of follow-up with only insulin treatment. The primary endpoint was the between-group difference in C-peptide area under the curve (AUC) following a liquid mixed-meal test after 52 weeks of treatment. RESULTS: Sixty-eight individuals were randomized. After 52 weeks, the 4-hour AUC C-peptide response was maintained with liraglutide, but decreased with placebo (P = .002). Six weeks after end-of-treatment, C-peptide AUCs were similar for liraglutide and placebo. The average required total daily insulin dose decreased from 0.30 to 0.23 units/kg/day with liraglutide, but increased from 0.29 to 0.43 units/kg/day in the placebo group at week 52 (P < .001). Time without the need for insulin treatment was observed in 13 versus two patients and lasted for 22 weeks (from 3 to 52 weeks) versus 6 weeks (from 4 to 8 weeks) on average for liraglutide and placebo, respectively. Patients treated with liraglutide had fewer episodes of hypoglycaemia compared with placebo-treated patients. The adverse events with liraglutide were predominantly gastrointestinal and transient. CONCLUSIONS: Treatment with liraglutide improves residual beta-cell function and reduces the dose of insulin during the first year after diagnosis. Beta-cell function was similar at 6 weeks postliraglutide treatment.

Targeted Delivery of Butyrate Improves Glucose Homeostasis, Reduces Hepatic Lipid Accumulation and Inflammation in db/db Mice.

Butyrate produced by the gut microbiota has beneficial effects on metabolism and inflammation. Butyrate-producing bacteria are supported by diets with a high fiber content, such as high-amylose maize starch (HAMS). We investigated the effects of HAMS- and butyrylated HAMS (HAMSB)-supplemented diets on glucose metabolism and inflammation in diabetic db/db mice. Mice fed HAMSB had 8-fold higher fecal butyrate concentration compared to control diet-fed mice. Weekly analysis of fasting blood glucose showed a significant reduction in HAMSB-fed mice when the area under the curve for all five weeks was analyzed. Following treatment, fasting glucose and insulin analysis showed increased homeostatic model assessment (HOMA) insulin sensitivity in the HAMSB-fed mice. Glucose-stimulated insulin release from isolated islets did not differ between the groups, while insulin content was increased by 36% in islets of the HAMSB-fed mice. Expression of insulin 2 was also significantly increased in islets of the HAMSB-fed mice, while no difference in expression of insulin 1, pancreatic and duodenal homeobox 1, MAF bZIP transcription factor A and urocortin 3 between the groups was observed. Hepatic triglycerides in the livers of the HAMSB-fed mice were significantly reduced. Finally, mRNA markers of inflammation in liver and adipose tissue were reduced in mice fed HAMSB. These findings suggest that HAMSB-supplemented diet improves glucose metabolism in the db/db mice, and reduces inflammation in insulin-sensitive tissues.

Increased levels of inflammatory factors are associated with severity of polyneuropathy in type 1 diabetes.

OBJECTIVE: Distal symmetrical polyneuropathy (DSPN) is a severe common long-term complication of type 1 diabetes caused by impaired sensory-motor nerve function. As chronic low-grade inflammation may be involved in the pathogenesis of DSPN, we investigated the circulating levels of inflammatory markers in individuals with type 1 diabetes with and without DSPN. Furthermore, we determined to what extent these factors correlated with different peripheral sensory nerve functions. DESIGN: Cross-sectional study. PATIENTS: The study included 103 individuals with type 1 diabetes with (n = 50) and without DSPN (n = 53) as well as a cohort of healthy controls (n = 21). MEASUREMENTS: Circulating levels of various inflammatory markers (cytokines, chemokines and soluble adhesion molecules) were determined in serum samples by Luminex multiplexing technology. Peripheral sensory nerve testing, for example vibration, tactile and thermal perception, was assessed by standardized procedures. RESULTS: The cytokines IL-1α, IL-4, IL-12p70, IL-13, IL-17A and TNF-α; the chemokine MCP-1; and the adhesion molecule E-selectin were significantly increased in individuals with type 1 diabetes with DSPN compared to those without DSPN (P < .001). These observations were independent of age, sex, BMI, disease duration and blood pressure. Additionally, higher serum concentrations of cytokines and chemokines were associated with higher vibration and tactile perception thresholds, but not with heat tolerance threshold. CONCLUSIONS: Individuals with type 1 diabetes and concomitant DSPN display higher serum levels of several inflammatory markers. These findings support that systemic low-grade inflammation may play a role in the pathogenesis of DSPN.

Systemic TNFα correlates with residual ß-cell function in children and adolescents newly diagnosed with type 1 diabetes.

BACKGROUND: Type 1 diabetes (T1D) is caused by immune-mediated destruction of the ß-cells. After initiation of insulin therapy many patients experience a period of improved residual ß-cell function leading to partial disease remission. Cytokines are important immune-modulatory molecules and contribute to ß-cell damage in T1D. The patterns of systemic circulating cytokines during T1D remission are not clear but may constitute biomarkers of disease status and progression. In this study, we investigated if the plasma levels of various pro- and anti-inflammatory cytokines around time of diagnosis were predictors of remission and residual ß-cell function in children with T1D followed for one year after disease onset. METHODS: In a cohort of 63 newly diagnosed children (33% females) with T1D with a mean age of 11.3 years (3.3-17.7), ten cytokines were measured of which eight were detectable in plasma samples by Mesoscale Discovery multiplex technology at study start and after 6 and 12 months. Linear regression models were used to evaluate association of cytokines with stimulated C-peptide. RESULTS: Systemic levels of tumor necrosis factor (TNF)-α, interleukin (IL)-2 and IL-6 inversely correlated with stimulated C-peptide levels over the entire study (P < 0.05). The concentrations of TNFα and IL-10 at study start predicted stimulated C-peptide level at 6 months (P = 0.011 and P = 0.043, respectively, adjusted for sex, age, HbA1c and stage of puberty). CONCLUSIONS: In recent-onset T1D, systemic cytokine levels, and in particular that of TNFα, correlate with residual ß-cell function and may serve as prognostic biomarkers of disease remission and progression to optimize treatment strategies. TRIAL REGISTRATION: The study was performed according to the criteria of the Helsinki II Declaration and was approved by the Danish Capital Region Ethics Committee on Biomedical Research Ethics (journal number H-3-2014-052). The parents of all participants gave written consent.

Circulating Inflammatory Markers Are Inversely Associated with Heart Rate Variability Measures in Type 1 Diabetes.

INTRODUCTION: A neuroimmune communication exists, and compelling evidence suggests that diabetic neuropathy and systemic inflammation are linked. Our aims were (1) to investigate biomarkers of the ongoing inflammation processes including cytokines, adhesion molecules, and chemokines and (2) to associate the findings with cardiovascular autonomic neuropathy in type 1 diabetes by measuring heart rate variability and cardiac vagal tone. MATERIALS AND METHODS: We included 104 adults with type 1 diabetes. Heart rate variability, time domain, and frequency domains were calculated from a 24-hour Holter electrocardiogram, while cardiac vagal tone was determined from a 5-minute electrocardiogram. Cytokines (interleukin- (IL-) 1α, IL-4, IL-12p70, IL-13, IL-17, and tumor necrosis factor- (TNF-) α), adhesion molecules (E-selectin, P-selectin, and intercellular adhesion molecule- (ICAM-) 1), and chemokines (chemokine (C-C motif) ligand (CCL)2, CCL3, CCL4, and C-X-C motif chemokine (CXCL)10) were assessed using a Luminex multiplexing technology. Associations between concentrations of inflammatory biomarkers and continuous variables of heart rate variability and cardiac vagal tone were estimated using multivariable linear regression adjusting for age, sex, disease duration, and smoking. RESULTS: Participants with the presence of cardiovascular autonomic neuropathy had higher systemic levels of IL-1α, IL-4, CCL2, and E-selectin than those without cardiovascular autonomic neuropathy. IL-1α, IL-4, IL-12, TNF-α, and E-selectin were inversely associated with both sympathetic and parasympathetic heart rate variability measures (p > 0.01). Discussion. Our results show that several pro- and anti-inflammatory factors, believed to be involved in the progression of diabetic polyneuropathy, are associated with cardiovascular autonomic neuropathy, suggesting that these factors may also contribute to the pathogenesis of cardiovascular autonomic neuropathy. Our findings emphasize the importance of the neuroimmune regulatory system in the pathogenesis of neuropathy in type 1 diabetes.

Low versus high carbohydrate diet in type 1 diabetes: A 12-week randomized open-label crossover study.

AIMS: To compare the effects of a low carbohydrate diet (LCD < 100 g carbohydrate/d) and a high carbohydrate diet (HCD > 250 g carbohydrate/d) on glycaemic control and cardiovascular risk factors in adults with type 1 diabetes. MATERIALS AND METHODS: In a randomized crossover study with two 12-week intervention arms separated by a 12-week washout, 14 participants using sensor-augmented insulin pumps were included. Individual meal plans meeting the carbohydrate criteria were made for each study participant. Actual carbohydrate intake was entered into the insulin pumps throughout the study. RESULTS: Ten participants completed the study. Daily carbohydrate intake during the two intervention periods was (mean ± standard deviation) 98 ± 11 g and 246 ± 34 g, respectively. Time spent in the range 3.9-10.0 mmol/L (primary outcome) did not differ between groups (LCD 68.6 ± 8.9% vs. HCD 65.3 ± 6.5%, P = 0.316). However, time spent <3.9 mmol/L was less (1.9 vs. 3.6%, P < 0.001) and glycaemic variability (assessed by coefficient of variation) was lower (32.7 vs. 37.5%, P = 0.013) during LCD. No events of severe hypoglycaemia were reported. Participants lost 2.0 ± 2.1 kg during LCD and gained 2.6 ± 1.8 kg during HCD (P = 0.001). No other cardiovascular risk factors, including fasting levels of lipids and inflammatory markers, were significantly affected. CONCLUSIONS: Compared with an intake of 250 g of carbohydrate per day, restriction of carbohydrate intake to 100 g per day in adults with type 1 diabetes reduced time spent in hypoglycaemia, glycaemic variability and weight with no effect on cardiovascular risk factors.

Hepatitis B virus upregulates host microRNAs that target apoptosis-regulatory genes in an in vitro cell model.

Chronic hepatitis B (CHB) infection increases the risk of developing severe liver disease including cirrhosis and hepatocellular carcinoma (HCC). As microRNAs may modulate host - virus interactions, we here investigated if hepatitis B virus (HBV) infection modulate microRNA expression using an in vitro HepG2 cell model system with inducible HBV replication. We found that HBV replication was associated with upregulation of miR-192-5p, miR-194-5p and miR-215-5p, of which miR-192-5p and miR-215-5p have identical seed sequences. Bioinformatics analyses revealed a significant enrichment of potential target genes involved in apoptosis signaling of all three microRNAs. In line with this, transfection with a mimic of miR-192-5p suppressed the protein level of pro-apoptotic BIM and reduced endoplasmic reticulum (ER) stress-induced apoptosis in HepG2 cells. In contrast, transfection with a mimic of miR-194-5p downregulated the anti-apoptotic proteins SODD and cFLIP, and sensitized HepG2 cells to both ER stress- and cytokine-induced apoptosis. In conclusion, our study suggests that HBV upregulates the expression of miR-192-5p and miR-194-5p in the host cell. These microRNAs target important apoptosis-regulatory proteins, and may thus contribute to the development of HBV-related liver disease.

Hepatitis B virus suppresses the secretion of insulin-like growth factor binding protein 1 to facilitate anti-apoptotic IGF-1 effects in HepG2 cells.

Hepatitis B virus (HBV) infection is a major global health burden as chronic hepatitis B (CHB) is associated with the development of liver diseases including hepatocellular carcinoma (HCC). To gain insight into the mechanisms causing HBV-related HCC, we investigated the effects of HBV replication on global host cell gene expression using human HepG2 liver cells. By microarray analysis, we identified 54 differentially expressed genes in HBV-replicating HepG2 cells. One of the differentially-expressed genes was insulin-like growth factor binding protein 1 (IGFBP1) which was downregulated in HBV-replicating cells. Consistent with the gene expression data, IGFBP1 was suppressed at both the cellular and secreted protein levels in the presence of HBV replication. Transient transfection experiments with an inducible plasmid encoding the HBV X protein (HBx) revealed that HBx alone was sufficient to modulate IGFBP1 expression. Small interference RNA (siRNA)-mediated loss of function studies revealed that knockdown of IGFBP1 reduced apoptosis induced by either thapsigargin (TG) or staurosporine (STS). Treatment of cells with recombinant insulin-like growth factor 1 (IGF-1) decreased both TG- or STS-induced apoptosis. Interestingly, addition of recombinant IGFBP1 reversed the anti-apoptotic effect of IGF-1 on TG-induced, but not STS-induced, apoptosis. In conclusion, our results suggest an anti-apoptotic autocrine function of HBV-mediated downregulation of IGFBP1 in HepG2 cells. Such an effect may contribute to the development of HBV-mediated HCC by increasing pro-survival and anti-apoptotic IGF-1 effects.

CTSH regulates ß-cell function and disease progression in newly diagnosed type 1 diabetes patients.

Over 40 susceptibility loci have been identified for type 1 diabetes (T1D). Little is known about how these variants modify disease risk and progression. Here, we combined in vitro and in vivo experiments with clinical studies to determine how genetic variation of the candidate gene cathepsin H (CTSH) affects disease mechanisms and progression in T1D. The T allele of rs3825932 was associated with lower CTSH expression in human lymphoblastoid cell lines and pancreatic tissue. Proinflammatory cytokines decreased the expression of CTSH in human islets and primary rat ß-cells, and overexpression of CTSH protected insulin-secreting cells against cytokine-induced apoptosis. Mechanistic studies indicated that CTSH exerts its antiapoptotic effects through decreased JNK and p38 signaling and reduced expression of the proapoptotic factors Bim, DP5, and c-Myc. CTSH overexpression also up-regulated Ins2 expression and increased insulin secretion. Additionally, islets from Ctsh(-/-) mice contained less insulin than islets from WT mice. Importantly, the TT genotype was associated with higher daily insulin dose and faster disease progression in newly diagnosed T1D patients, indicating agreement between the experimental and clinical data. In line with these observations, healthy human subjects carrying the T allele have lower ß-cell function, which was evaluated by glucose tolerance testing. The data provide strong evidence that CTSH is an important regulator of ß-cell function during progression of T1D and reinforce the concept that candidate genes for T1D may affect disease progression by modulating survival and function of pancreatic ß-cells, the target cells of the autoimmune assault.

Temporal profiling of cytokine-induced genes in pancreatic ß-cells by meta-analysis and network inference.

Type 1 Diabetes (T1D) is an autoimmune disease where local release of cytokines such as IL-1ß and IFN-γ contributes to ß-cell apoptosis. To identify relevant genes regulating this process we performed a meta-analysis of 8 datasets of ß-cell gene expression after exposure to IL-1ß and IFN-γ. Two of these datasets are novel and contain time-series expressions in human islet cells and rat INS-1E cells. Genes were ranked according to their differential expression within and after 24 h from exposure, and characterized by function and prior knowledge in the literature. A regulatory network was then inferred from the human time expression datasets, using a time-series extension of a network inference method. The two most differentially expressed genes previously unknown in T1D literature (RIPK2 and ELF3) were found to modulate cytokine-induced apoptosis. The inferred regulatory network is thus supported by the experimental validation, providing a proof-of-concept for the proposed statistical inference approach.

Skeletal muscle apolipoprotein B expression reduces muscular triglyceride accumulation.

BACKGROUND: Lipid accumulation in skeletal muscle is associated with impaired insulin sensitivity in type 2 diabetes. In cardiac myocytes, lipoprotein secretion controlled by apolipoproteinB (apoB) and microsomal triglyceride transfer protein (MTP) affects lipid homeostasis. DESIGN: In this study, we investigated whether expression of a human apoB transgene affects triglyceride accumulation and insulin sensitivity in skeletal muscle in fat fed obese mice. RESULTS: Expression of apoB and MTP mRNA and the human apoB transgene was seen in skeletal muscle of the transgene mice. Human apoB transgenic mice accumulated 28% less triglycerides in skeletal myocytes after one year of fat-feeding as compared with WT mice (32 ± 5, n = 10 vs. 44 ± 4 nmol/mg ww, n = 13, p = 0.04). Moreover, expression of human apoB in fat-fed mice was associated with 32% (p = 0.02) and 37% (p = 0.01) lower plasma insulin levels after 9 and 12 months, respectively, improved intra peritoneal glucose tolerance after 6 months, and a trend towards increased insulin-stimulated glucose uptake in isolated skeletal muscle. CONCLUSIONS: The data suggests that overexpression of apoB decreases skeletal muscle lipid accumulation and attenuates peripheral insulin resistance in obese mice.

Huntingtin-interacting protein 14 is a type 1 diabetes candidate protein regulating insulin secretion and beta-cell apoptosis.

Type 1 diabetes (T1D) is a complex disease characterized by the loss of insulin-secreting ß-cells. Although the disease has a strong genetic component, and several loci are known to increase T1D susceptibility risk, only few causal genes have currently been identified. To identify disease-causing genes in T1D, we performed an in silico "phenome-interactome analysis" on a genome-wide linkage scan dataset. This method prioritizes candidates according to their physical interactions at the protein level with other proteins involved in diabetes. A total of 11 genes were predicted to be likely disease genes in T1D, including the INS gene. An unexpected top-scoring candidate gene was huntingtin-interacting protein (HIP)-14/ZDHHC17. Immunohistochemical analysis of pancreatic sections demonstrated that HIP14 is almost exclusively expressed in insulin-positive cells in islets of Langerhans. RNAi knockdown experiments established that HIP14 is an antiapoptotic protein required for ß-cell survival and glucose-stimulated insulin secretion. Proinflammatory cytokines (IL-1ß and IFN-γ) that mediate ß-cell dysfunction in T1D down-regulated HIP14 expression in insulin-secreting INS-1 cells and in isolated rat and human islets. Overexpression of HIP14 was associated with a decrease in IL-1ß-induced NF-κB activity and protection against IL-1ß-mediated apoptosis. Our study demonstrates that the current network biology approach is a valid method to identify genes of importance for T1D and may therefore embody the basis for more rational and targeted therapeutic approaches.

Elevated Cathepsin S Serum Levels in New-Onset Type 1 Diabetes and Autoantibody-Positive Siblings.

Accumulating data suggest a role for the lysosomal protease cathepsin S (CTSS) in type 1 diabetes. Circulating CTSS is increased in type 1 diabetes; however, whether CTSS has protective or deleterious effects is unclear. The study's objectives were to examine the biomarker potential of CTSS in new-onset type 1 diabetes, and to investigate the expression and secretion of CTSS in human islets and ß-cells. The CTSS level was analyzed in serum from children with new-onset type 1 diabetes and autoantibody-positive and -negative siblings by ELISA. The expression and secretion of CTSS were evaluated in isolated human islets and EndoC-ßH5 cells by real-time qPCR, immunoblotting, and ELISA. The CTSS serum level was elevated in children with new-onset type 1 diabetes and positively associated with autoantibody status in healthy siblings. Human islets and EndoC-ßH5 cells demonstrated induction and secretion of CTSS after exposure to proinflammatory cytokines, a model system of islet inflammation. Analysis of publicly available single-cell RNA sequencing data on human islets showed that elevated CTSS expression was exclusive for the ß-cells in donors with type 1 diabetes as compared with nondiabetic donors. These findings suggest a potential of CTSS as a diagnostic biomarker in type 1 diabetes.

Transcutaneous vagus nerve stimulation has no anti-inflammatory effect in diabetes.

Chronic inflammation is associated with diabetes and contributes to the development and progression of micro- and macrovascular complications. Transcutaneous vagus nerve stimulation (tVNS) has been proposed to reduce levels of circulating inflammatory cytokines in non-diabetics by activating the cholinergic anti-inflammatory pathway. We investigated the anti-inflammatory potential of tVNS as a secondary endpoint of a randomized controlled trial in people with diabetes (NCT04143269). 131 people with diabetes (type 1: n = 63; type 2: n = 68), gastrointestinal symptoms and various degrees of autonomic neuropathy were included and randomly assigned to self-administer active (n = 63) or sham (n = 68) tVNS over two successive study periods: (1) Seven days with four daily administrations and, (2) 56 days with two daily administrations. Levels of systemic inflammatory cytokines (IL-6, IL-8, IL-10, TNF-α, IFN-γ) were quantified from blood samples by multiplex technology. Information regarding age, sex, diabetes type, and the presence of cardiac autonomic neuropathy (CAN) was included in the analysis as possible confounders. No differences in either cytokine were seen after study period 1 and 2 between active and sham tVNS (all p-values > 0.08). Age, sex, diabetes type, presence of CAN, and baseline levels of inflammatory cytokines were not associated with changes after treatment (all p-values > 0.07). A tendency towards slight reductions in TNF-α levels after active treatment was observed in those with no CAN compared to those with early or manifest CAN (p = 0.052). In conclusion, tVNS did not influence the level of systemic inflammation in people with diabetes.

Effects of probiotics and fibers on markers of nephropathy, inflammation, intestinal barrier dysfunction and endothelial dysfunction in individuals with type 1 diabetes and albuminuria. The ProFOS Study.

AIMS: To estimate whether a mix of pre- and probiotics would strengthen the gut barrier and protect the kidneys in individuals with type 1 diabetes and albuminuria. METHODS: Randomized, placebo-controlled, crossover study. Forty-one participants received synbiotic (pre- and probiotics) mix or placebo for 12 weeks with 6 weeks washout. Primary endpoint was change from baseline to end-of-period in UACR. Secondary endpoints were changes in endothelial glycocalyx thickness, inflammatory and intestinal barrier dysfunction markers, glomerular filtration rate (GFR) and ambulatory systolic blood pressure. RESULTS: Thirty-five participants completed the study. Mean age was 58 (SD 10) years, 73 % (n = 30) were male, median UACR was 134 (IQR 63-293) mg/g, estimated GFR was 75 (30) ml/min/1.73m2. There was no significant difference in UACR with a mean relative change (CI 95 %) from baseline to end-of-treatment of -3.0 (-18.4; 15.5) % in the synbiotic group and -12.0 (-29.6; 9.6) % in the placebo group with no significant difference between treatment periods (9.37 (-25.2; 44.0) percentage points; p = 0.60). No significant beneficial difference in the secondary end points was demonstrated. CONCLUSION: Twelve weeks treatment with synbiotic mix had no effect on UACR or on any of the secondary endpoints in subjects with type 1 diabetes and albuminuria.

Loss of electrical ß-cell to δ-cell coupling underlies impaired hypoglycaemia-induced glucagon secretion in type-1 diabetes.

Diabetes mellitus involves both insufficient insulin secretion and dysregulation of glucagon secretion1. In healthy people, a fall in plasma glucose stimulates glucagon release and thereby increases counter-regulatory hepatic glucose production. This response is absent in many patients with type-1 diabetes (T1D)2, which predisposes to severe hypoglycaemia that may be fatal and accounts for up to 10% of the mortality in patients with T1D3. In rats with chemically induced or autoimmune diabetes, counter-regulatory glucagon secretion can be restored by SSTR antagonists4-7 but both the underlying cellular mechanism and whether it can be extended to humans remain unestablished. Here, we show that glucagon secretion is not stimulated by low glucose in isolated human islets from donors with T1D, a defect recapitulated in non-obese diabetic mice with T1D. This occurs because of hypersecretion of somatostatin, leading to aberrant paracrine inhibition of glucagon secretion. Normally, KATP channel-dependent hyperpolarization of ß-cells at low glucose extends into the δ-cells through gap junctions, culminating in suppression of action potential firing and inhibition of somatostatin secretion. This 'electric brake' is lost following autoimmune destruction of the ß-cells, resulting in impaired counter-regulation. This scenario accounts for the clinical observation that residual ß-cell function correlates with reduced hypoglycaemia risk8.

Effects of 3 months of 10-h per-day time-restricted eating and 3 months of follow-up on bodyweight and cardiometabolic health in Danish individuals at high risk of type 2 diabetes: the RESET single-centre, parallel, superiority, open-label, randomised controlled trial.

BACKGROUND: Time-restricted eating (TRE) has been suggested to be a simple, feasible, and effective dietary strategy for individuals with overweight or obesity. We aimed to investigate the effects of 3 months of 10-h per-day TRE and 3 months of follow-up on bodyweight and cardiometabolic risk factors in individuals at high risk of type 2 diabetes. METHODS: This was a single-centre, parallel, superiority, open-label randomised controlled clinical trial conducted at Steno Diabetes Center Copenhagen (Denmark). The inclusion criteria were age 30-70 years with either overweight (ie, BMI ≥25 kg/m2) and concomitant prediabetes (ie, glycated haemoglobin [HbA1c] 39-47 mmol/mol) or obesity (ie, BMI ≥30 kg/m2) with or without prediabetes and a habitual self-reported eating window (eating and drinking [except for water]) of 12 h per day or more every day and of 14 h per day or more at least 1 day per week. Individuals were randomly assigned 1:1 to 3 months of habitual living (hereafter referred to as the control group) or TRE, which was a self-selected 10-h per-day eating window placed between 0600 h and 2000 h. Randomisation was done in blocks varying in size and was open for participants and research staff, but outcome assessors were masked during statistical analyses. The randomisation list was generated by an external statistician. The primary outcome was change in bodyweight, assessed after 3 months (12 weeks) of the intervention and after 3 months (13 weeks) of follow-up. Adverse events were reported and registered at study visits or if participants contacted study staff to report events between visits. This trial is registered on ClinicalTrials.gov (NCT03854656). FINDINGS: Between March 12, 2019, and March 2, 2022, 100 participants (66 [66%] were female and 34 [34%] were male; median age 59 years [IQR 52-65]) were enrolled and randomly assigned (50 to each group). Of those 100, 46 (92%) in the TRE group and 46 (92%) in the control group completed the intervention period. After 3 months of the intervention, there was no difference in bodyweight between the TRE group and the control group (-0·8 kg, 95% CI -1·7 to 0·2; p=0·099). Being in the TRE group was not associated with a lower bodyweight compared with the control group after subsequent 3-month follow-up (-0·2 kg, -1·6 to 1·2). In the per-protocol analysis, participants who completed the intervention in the TRE group lost 1·0 kg (-1·9 to -0·0; p=0·040) bodyweight compared with the control group after 3 months of intervention, which was not maintained after the 3-month follow-up period (-0·4 kg, -1·8 to 1·0). During the trial and follow-up period, one participant in the TRE group reported a severe adverse event: development of a subcutaneous nodule and pain when the arm was in use. This side-effect was evaluated to be related to the trial procedures. INTERPRETATION: 3 months of 10-h per-day TRE did not lead to clinically relevant effects on bodyweight in middle-aged to older individuals at high risk of type 2 diabetes. FUNDING: Novo Nordisk Foundation, Aalborg University, Helsefonden, and Innovation Fund Denmark.

Do post-translational beta cell protein modifications trigger type 1 diabetes?

Type 1 diabetes is considered an autoimmune disease characterised by specific T cell-mediated destruction of the insulin-producing beta cells. Yet, except for insulin, no beta cell-specific antigens have been discovered. This may imply that the autoantigens in type 1 diabetes exist in modified forms capable of specifically triggering beta cell destruction. In other immune-mediated diseases, autoantigens targeted by the immune system have undergone post-translational modification (PTM), thereby creating tissue-specific neo-epitopes. In a similar manner, PTM of beta cell proteins might create beta cell-specific neo-epitopes. We suggest that the current paradigm of type 1 diabetes as a classical autoimmune disease should be reconsidered since the immune response may not be directed against native beta cell proteins. A modified model for the pathogenetic events taking place in islets leading to the T cell attack against beta cells is presented. In this model, PTM plays a prominent role in triggering beta cell destruction. We discuss literature of relevance and perform genetic and human islet gene expression analyses. Both direct and circumstantial support for the involvement of PTM in type 1 diabetes exists in the published literature. Furthermore, we report that cytokines change the expression levels of several genes encoding proteins involved in PTM processes in human islets, and that there are type 1 diabetes-associated polymorphisms in a number of these. In conclusion, data from the literature and presented experimental data support the notion that PTM of beta cell proteins may be involved in triggering beta cell destruction in type 1 diabetes. If the beta cell antigens recognised by the immune system foremost come from modified proteins rather than native ones, the concept of type 1 diabetes as a classical autoimmune disease is open for debate.

Candidate genes expressed in human islets and their role in the pathogenesis of type 1 diabetes.

In type 1 diabetes (T1D), the insulin-producing ß cells are destroyed by an immune-mediated process leading to complete insulin deficiency. There is a strong genetic component in T1D. Genes located in the human leukocyte antigen (HLA) region are the most important genetic determinants of disease, but more than 40 additional loci are known to significantly affect T1D risk. Since most of the currently known genetic candidates have annotated immune cell functions, it is generally considered that most of the genetic susceptibility in T1D is caused by variation in genes affecting immune cell function. Recent studies, however, indicate that most T1D candidate genes are expressed in human islets suggesting that the functions of the genes are not restricted to immune cells, but also play roles in the islets and possibly the ß cells. Several candidates change expression levels within the islets following exposure to proinflammatory cytokines highlighting that these genes may be involved in the response of ß cells to immune attack. In this review, the compiling evidence that many of the candidate genes are expressed in islets and ß cells will be presented. Further, we perform the first systematic human islet expression analysis of all genes located in 50 T1D-associated GWAS loci using a published RNA sequencing dataset. We find that 336 out of 857 genes are expressed in human islets and that many of these interact in protein networks. Finally, the potential pathogenetic roles of some candidate genes will be discussed.