Intestinal glucagon-like peptide-1:A new regulator of impaired counterregulatory responses to hypoglycemia in type 1 diabetes mellitus

In this article,we review the study by Jin et al,which examined the role of intestinal glucagon-like peptide-1(GLP-1)in counterregulatory responses to hypoglycemia in patients with type 1 diabetes mellitus(T1DM).With the global rise of T1DM,there is an increased burden on society and healthcare systems.Due to insulin therapy and islet dysfunction,T1DM patients are highly vulnerable to severe hypoglycemia,a leading cause of mortality.In healthy individuals,counterregulatory mechanisms restore blood glucose during hypoglycemia,but repeated episodes impair these responses.Jin et al demonstrated that overexpression of GLP-1 attenuates the sympathetic-adrenal reflex and disrupts the secretion of counterregulatory hormones such as glucagon during hypoglycemia,leading to counterregulatory dysfunction.These findings highlight the critical role of GLP-1 in the impaired counterregulatory response to hypoglycemia in T1DM patients and provide new insights into the potential application of GLP-1-related therapies in T1DM patients.

Role of gut-liver axis and glucagon-like peptide-1 receptor agonists in the treatment of metabolic dysfunction-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease(MAFLD)is a hepatic manifestation of the metabolic syndrome.It is one of the most common liver diseases worldwide and shows increasing prevalence rates in most countries.MAFLD is a progressive disease with the most severe cases presenting as advanced fibrosis or cirrhosis with an increased risk of hepatocellular carcinoma.Gut microbiota play a significant role in the pathogenesis and progression of MAFLD by disrupting the gut-liver axis.The mechanisms involved in maintaining gut-liver axis homeostasis are complex.One critical aspect involves preserving an appropriate intestinal barrier permeability and levels of intestinal lumen metabolites to ensure gutliver axis functionality.An increase in intestinal barrier permeability induces metabolic endotoxemia that leads to steatohepatitis.Moreover,alterations in the absorption of various metabolites can affect liver metabolism and induce liver steatosis and fibrosis.Glucagon-like peptide-1 receptor agonists(GLP-1 RAs)are a class of drugs developed for the treatment of type 2 diabetes mellitus.They are also commonly used to combat obesity and have been proven to be effective in reversing hepatic steatosis.The mechanisms reported to be involved in this effect include an improved regulation of glycemia,reduced lipid synthesis,β-oxidation of free fatty acids,and induction of autophagy in hepatic cells.Recently,multiple peptide receptor agonists have been introduced and are expected to increase the effectiveness of the treatment.A modulation of gut microbiota has also been observed with the use of these drugs that may contribute to the amelioration of MAFLD.This review presents the current understanding of the role of the gutliver axis in the development of MAFLD and use of members of the GLP-1 RA family as pleiotropic agents in the treatment of MAFLD.

Intestinal glucagon-like peptide-1:A new player associated with impaired counterregulatory responses to hypoglycaemia in type 1 diabetic mice

BACKGROUND Impaired hypoglycaemic counterregulation has emerged as a critical concern for diabetic patients who may be hesitant to medically lower their blood glucose levels due to the fear of potential hypoglycaemic reactions.However,the pathogenesis of hypoglycaemic counterregulation is still unclear.Glucagon-like peptide-1(GLP-1)and its analogues have been used as adjunctive therapies for type 1 diabetes mellitus(T1DM).The role of GLP-1 in counterregulatory dysfunction during hypoglycaemia in patients with T1DM has not been reported.AIM To explore the impact of intestinal GLP-1 on impaired hypoglycaemic counterregulation in type 1 diabetic mice.METHODS T1DM was induced in C57BL/6J mice using streptozotocin,followed by intraperitoneal insulin injections to create T1DM models with either a single episode of hypoglycaemia or recurrent episodes of hypoglycaemia(DH5).Immunofluorescence,Western blot,and enzyme-linked immunosorbent assay were employed to evaluate the influence of intestinal GLP-1 on the sympathetic-adrenal reflex and glucagon(GCG)secretion.The GLP-1 receptor agonist GLP-1(7-36)or the antagonist exendin(9-39)were infused into the terminal ileum or injected intraperitoneally to further investigate the role of intestinal GLP-1 in hypoglycaemic counterregulation in the model mice.RESULTS The expression levels of intestinal GLP-1 and its receptor(GLP-1R)were significantly increased in DH5 mice.Consecutive instances of excess of intestinal GLP-1 weakens the sympathetic-adrenal reflex,leading to dysfunction of adrenal counterregulation during hypoglycaemia.DH5 mice showed increased pancreaticδ-cell mass,cAMP levels inδcells,and plasma somatostatin concentrations,while cAMP levels in pancreaticαcells and plasma GCG levels decreased.Furthermore,GLP-1R expression in islet cells and plasma active GLP-1 levels were significantly increased in the DH5 group.Further experiments involving terminal ileal infusion and intraperitoneal injection in the model mice demonstrated that intestinal GLP-1 during recurrent hypoglycaemia hindered the secretion of the counterregulatory hormone GCG via the endocrine pathway.CONCLUSION Excessive intestinal GLP-1 is strongly associated with impaired counterregulatory responses to hypoglycaemia,leading to reduced appetite and compromised secretion of adrenaline,noradrenaline,and GCG during hypoglycaemia.

Glucagon-like peptide-1 receptor agonists as a possible intervention to delay the onset of type 1 diabetes:A new horizon

Type 1 diabetes(T1D)is a chronic autoimmune condition that destroys insulinproducing beta cells in the pancreas,leading to insulin deficiency and hyperglycemia.The management of T1D primarily focuses on exogenous insulin replacement to control blood glucose levels.However,this approach does not address the underlying autoimmune process or prevent the progressive loss of beta cells.Recent research has explored the potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)as a novel intervention to modify the disease course and delay the onset of T1D.GLP-1RAs are medications initially developed for treating type 2 diabetes.They exert their effects by enhancing glucose-dependent insulin secretion,suppressing glucagon secretion,and slowing gastric emptying.Emerging evidence suggests that GLP-1RAs may also benefit the treatment of newly diagnosed patients with T1D.This article aims to highlight the potential of GLP-1RAs as an intervention to delay the onset of T1D,possibly through their potential immunomodulatory and anti-inflammatory effects and preservation of beta-cells.This article aims to explore the potential of shifting the paradigm of T1D management from reactive insulin replacement to proactive disease modification,which should open new avenues for preventing and treating T1D,improving the quality of life and long-term outcomes for individuals at risk of T1D.

Is it necessary to stop glucagon-like peptide-1 receptor agonists prior to endoscopic procedure? A retrospective study

BACKGROUND Glucagon-like peptide-1 receptor agonists(GLP-1 RA)are effective in diabetes and obesity,reducing hyperglycemia by increasing insulin release and delaying gastric emptying.However,they can cause gastroparesis,raising concerns about aspiration during procedures.Recent guidelines advise discontinuing GLP-1 RA before surgery to reduce the risk of pulmonary aspiration.AIM To evaluate the effect of GLP-1 RAs on gastric residual contents during endosco-pic procedures.METHODS A retrospective chart review at BronxCare Health System,New York,from January 2019 to October 2023,assessed gastric residue and aspiration in GLP-1 RA patients undergoing endoscopic procedures.Two groups were compared based on dietary status before the procedure.Data included demographics,symptoms of gastroparesis,opiate use,hemoglobin A1c,GLP-1 agonist indication,endo-scopic details,and aspiration occurrence.IBM SPSS was used for analysis,cal-culating means,standard deviations,and applying Pearson’s chi-square and t-tests for associations,with P<0.05 as being significant.RESULTS During the study,306 patients were included,with 41.2%on a clear liquid/low residue diet and 58.8%on a regular diet before endoscopy.Most patients(63.1%)were male,with a mean age of 60±12 years.The majority(85.6%)were on GLP-1 RAs for diabetes,and 10.1%reported digestive symptoms before endoscopy.Among those on a clear liquid diet,1.5%had residual food at endoscopy compared to 10%on a regular diet,which was statistically significant(P=0.03).Out of 31 patients with digestive symptoms,13%had residual food,all from the regular diet group(P=0.130).No complications were reported during or after the procedures.CONCLUSION The study reflects a significant rise in GLP-1 RA use for diabetes and obesity.A 24-hour liquid diet seems safe for endoscopic procedures without aspiration.Patients with upper gastrointestinal symptoms might have a higher residual food risk,though not statistically significant.Further research is needed to assess risks based on diabetes duration,gastroparesis,and GLP-1 RA dosing,aiming to minimize interruptions in therapy during procedures.

Practical guide:Glucagon-like peptide-1 and dual glucosedependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonists in diabetes mellitus

Practical guide:Glucagon-like peptide-1 and dual glucosedependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonists in diabetes mellitus common second-line choice after metformin for treating T2DM.Various considerations can make selecting and switching between different GLP-1 RAs challenging.Our study aims to provide a comprehensive guide for the usage of GLP-1 RAs and dual GIP and GLP-1 RAs for the management of T2DM.

Role of intestinal glucagon-like peptide-1 in impaired counterregulatory responses to hypoglycemia

Patients with type 1 diabetes mellitus(T1DM)experience multiple episodes of hypoglycemia,resulting in dysfunctional counter-regulatory responses with time.The recent experimental study by Jin et al explored the role of intestinal glucagon-like peptide-1(GLP-1)in impaired counter-regulatory responses to hypoglycemia.They identified intestinal GLP-1 along with GLP-1 receptor(GLP-1R)as the new key players linked with impaired counter-regulatory responses to hypoglycemia in type 1 diabetic mice.They also demonstrated that excessive expression of GLP-1 and GLP-1R was associated with attenuated sympathoadrenal responses and decreased glucagon secretion.The study has enormous clinical relevance as de-fective counter regulation and hypoglycemia unawareness negatively impacts the intensive glycemic management approach in this group of patients.However,the physiological processes must be validated in dedicated human studies to compre-hensively understand the pathophysiology of this complex relationship,and to clarify the true extent of impaired hypoglycemia counter regulation by intestinal GLP-1.For now,following the results of the index study and other similar studies,GLP-1 analogues usage in T1DM must be carefully monitored,as there is an inherent risk of worsening the already impaired counter-regulatory responses in these patients.Further studies in the future could identify other key players in-volved in this clinically relevant interaction.

Intestinal glucagon-like peptide-1 in hypoglycemic counterregulation for type 1 diabetes management

Type 1 diabetes(T1D)is characterized by the autoimmune destruction of pan-creatic beta cells,leading to absolute insulin deficiency and the need for exoge-nous insulin.A significant concern in T1D management is hypoglycemia,which is worsened by impaired counterregulatory mechanisms.Effective counterregu-lation involves hormones such as glucagon and adrenaline,which work to restore normal blood glucose levels.However,in T1D,these mechanisms often fail,par-ticularly after recurrent hypoglycemia,resulting in hypoglycemia-associated au-tonomic failure.Recent research indicates that elevated levels of intestinal glu-cagon-like peptide-1(GLP-1)impair counterregulatory responses by reducing the secretion of glucagon and adrenaline.This editorial underscores GLP-1’s role be-yond its incretin effects,contributing to impaired hypoglycemic counterregu-lation.This understanding necessitates a nuanced approach to GLP-1-based the-rapies in T1D,balancing the benefits of glycemic control with potential risks.Future research should delve into the mechanisms behind GLP-1’s effects and explore potential interventions to improve hypoglycemic counterregulation.The goal is to enhance the safety and quality of life for T1D patients.

Role of intestinal glucagon-like peptide-1 in hypoglycemia response impairment in type 1 diabetes

This study critically examines the novel findings presented by Jin et al,which explores the role of intestinal glucagon-like peptide-1(GLP-1)in impaired counterregulatory responses to hypoglycemia in mice with type 1 diabetes.The study identifies intestinal GLP-1 as a significant determinant in the physiological responses to hypoglycemia,offering new insights into its potential implications for diabetes management.The editorial synthesizes these findings,discusses their relevance in the context of current diabetes research,and outlines potential avenues for future investigation of intestinal GLP-1 as a therapeutic target.This analysis underscores the need for continued research into the complex mechanisms underlying impaired hypoglycemia responses and highlights the potential of targeting intestinal GLP-1 pathways in therapeutic strategies for type 1 diabetes.

Glucagon-like peptide-1 agonists:Role of the gut in hypoglycemia unawareness,and the rationale in type 1 diabetes

Type 1 diabetes is increasing and the majority of patients have poor glycemic control.Although advanced technology and nanoparticle use have greatly enhanced insulin delivery and glucose monitoring,weight gain and hypoglycemia remain major challenges and a constant source of concern for patients with type 1 diabetes.Type 1 diabetes shares some pathophysiology with type 2 diabetes,and an overlap has been reported.The above observation created great interest in glucagon-like peptide-1 receptor agonists(GLP-1)as adjuvants for type 1 diabetes.Previous trials confirmed the positive influence of GLP-1 agonists onβcell function.However,hypoglycemia unawareness and dysregulated glucagon response have been previously reported in patients with recurrent hypoglycemia using GLP-1 agonists.Jin et al found that the source of glucagon dysregulation due to GLP-1 agonists resides in the gut.Plausible explanations could be gut nervous system dysregulation or gut microbiota disruption.This review evaluates the potential of GLP-1 agonists in managing type 1 diabetes,particularly focusing on their impact on glycemic control,weight management,and glucagon dysregulation.We provide a broader insight into the problem of type 1 diabetes mellitus management in the light of recent findings and provide future research directions.

Glucagon-like peptide-1 receptor agonists:Exploring the mechanisms from glycemic control to treatment of multisystemic diseases

This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associated fatty liver disease.We provide supplementary insights to their research,highlighting the broader systemic implications of GLP-1RAs,synthesizing the current understanding of their mechanisms and the trajectory of research in this field.GLP-1RAs are revolutionizing the treatment of type 2 diabetes mellitus and beyond.Beyond glycemic control,GLP-1RAs demonstrate cardiovascular and renal protective effects,offering potential in managing diabetic kidney disease alongside renin–angiotensin–aldosterone system inhibitors.Their role in bone metabolism hints at benefits for diabetic osteoporosis,while the neuroprotective properties of GLP-1RAs show promise in Alzheimer's disease treatment by modulating neuronal insulin signaling.Additionally,they improve hormonal and metabolic profiles in polycystic ovary syndrome.This editorial highlights the multifaceted mechanisms of GLP-1RAs,emphasizing the need for ongoing research to fully realize their therapeutic potential across a range of multisystemic diseases.

Cardioprotective effects of glucagon-like peptide 1 receptor agonists in heart failure: Myth or truth?

Therapy with glucagon-like peptide 1(GLP1)receptor agonists has raised great interest for its beneficial cardiovascular effects in preventing atherosclerosis and heart failure-related outcomes.However,while evidence about atherosclerosis consistently suggests a cardioprotective potential with class effect,controversies remain on its impact on heart failure.GLP1 receptor agonists appear to prevent hospitalization for new-onset heart failure and reduce symptoms in heart failure with preserved ejection fraction(as demonstrated by the recent STEP-HFpEF Trial).Still,GLP1 agonism has resulted in neutral or even harmful effects in patients with established heart failure with reduced ejection fraction(the LIVE trial).GLP1 receptor agonists benefit the cardiovascular system indirectly through their marked metabolic effects(improved weight management,glycemic control,blood pressure,systemic and tissue inflammation),while direct effects on the heart have been questioned.Nonetheless,weight loss alone achieved through GLP1 receptor agonists has failed in improving left ventricular functions.Tirzepatide is a dual agonist of GLP1 and glucose-dependent insulinotropic polypeptide,representing an innovative treatment option in diabetes with a major impact on weight loss and promising cardiovascular benefits.Whether this class of therapies is going to change the history of heart failure is an ongoing debate.

Effects of glucagon-like peptide-1 receptor agonists on non-alcoholic fatty liver disease and inflammation

Glucagon-like peptide1 (GLP-1) is secreted from Langerhans cells in response to oral nutrient intake. Glucagon- like peptide-1 receptor agonists (GLP-1RAs) are a new class of incretin-based anti-diabetic drugs. They function to stimulate insulin secretion while suppressing glucagon secretion. GLP-1-based therapies are now well established in the management of type 2 diabetes mellitus (T2DM), and recent literature has suggested potential applications of these drugs in the treatment of obesity and for protection against cardiovascular and neurological diseases. As we know, along with change in lifestyles, the prevalence of non-alcoholic fatty liver disease (NAFLD) in China is rising more than that of viral hepatitis and alcoholic fatty liver disease, and NAFLD has become the most common chronic liver disease in recent years. Recent studies further suggest that GLP-1RAs can reduce transaminase levels to improve NAFLD by improving blood lipid levels, cutting down the fat content to promote fat redistribution, directly decreasing fatty degeneration of the liver, reducing the degree of liver fibrosis and improving inflammation. This review shows the NAFLD-associated effects of GLP-1RAs in animal models and in patients with T2DM or obesity who are participants in clinical trials. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.

Potential roles of glucagon-like peptide-1-based therapies in treating non-alcoholic fatty liver disease

Glucagon-like peptide-1(GLP-1)-based therapies have demonstrated efficacy and safety in treating type 2 diabetes, which shares a similar pathophysiological mechanism with non-alcoholic fatty liver disease(NAFLD). Recent studies showed that glucose-induced GLP-1 secretion was decreased in patients with NAFLD and that the level of dipeptidyl peptidase-4, which inactivates intact GLP-1, was upregulated. Moreover, the expression of the GLP-1 receptor was downregulated in livers from patients with NAFLD, indicating an association of defective GLP-1 signalling with NAFLD. Notably, GLP-1-based therapies are reported to be effective in improving hepatic endpoints in patients with NAFLD, such as reducing hepatic fat content, hepatic steatosis and plasma transaminase levels, and preventing fibrosis. GLP-1-based therapies are beneficial for body weight control and glycaemic normalisation, which are important for the management of NAFLD. Moreover, clinical and preclinical studies showed that GLP-1-based agents might directly exert their actions on the liver through activation of functional GLP-1 receptors in hepatocytes.The possible mechanisms involve regulating gene expression that is associated with insulin resistance and lipid metabolism, and suppressing oxidative stress in the liver cells, thus preventing the development and progression of NAFLD. Based on these promising data, large-scale randomised controlled trials are warranted to assess the efficacy and safety of GLP-1-based therapies in treating NAFLD.

Coagonist of glucagon-like peptide-1 and glucagon receptors ameliorates kidney injury in murine models of obesity and diabetes mellitus

AIM To investigate the role of glucagon-like peptide-1(GLP-1)/glucagon receptors coagonist on renal dysfunction associated with diabetes and obesity. METHODS Chronic high-fat diet fed C57 BL/6 J mice, streptozotocintreated high-fat diet fed C57 BL/6 J mice and diabeticC57 BLKS/J db/db mice were used as models of diabetes-induced renal dysfunction. The streptozotocintreated high-fat diet fed mice and db/db mice were treated with the GLP-1 and glucagon receptors coagonist(Aib2 C24 Chimera2, 150 μg/kg, sc) for twelve weeks, while in chronic high-fat diet fed mice, coagonist(Aib2 C24 Chimera2, 150 μg/kg, sc) treatment was continued for forty weeks. Kidney function, histology, fibrosis, inflammation, and plasma biochemistry were assessed at the end of the treatment. RESULTS Coagonist treatment decreased body weight, plasma lipids, insulin resistance, creatinine, blood urea nitrogen, urinary albumin excretion rate and renal lipids. In kidney, expression of lipogenic genes(SREBP-1 C, FAS, and SCD-1) was decreased, and expression of genes involved in β-oxidation(CPT-1 and PPAR-α) was increased due to coagonist treatment. In plasma, coagonist treatment increased adiponectin and FGF21 and decreased IL-6 and TNF-?. Coagonist treatment reduced expression of inflammatory(TNF-α, MCP-1, and MMP-9) and pro-fibrotic(TGF-β, COL1 A1, and α-SMA) genes and also improved histological derangement in renal tissue.CONCLUSION Coagonist of GLP-1 and glucagon receptors alleviated diabetes and obesity-induced renal dysfunction by reducing glucose intolerance, obesity, and hyperlipidemia.

Significance of serum glucagon-like peptide-1 and matrix Gla protein levels in patients with diabetes and osteoporosis

BACKGROUND Osteoporosis is a systemic bone disease characterized by decreased bone mass,impaired bone mass,and reduced bone strength that leads to increased bone fragility and fracture.Type 2 diabetes mellitus(T2DM)complicated with osteoporosis is a common systemic metabolic bone disease,and reduced bone mass and bone strength are considered the main clinical features;however,the pathogenesis of this disease has not been fully clarified.Its occurrence is considered related to sex,age,and genetic factors.There are many risk factors for diabetes complicated with osteoporosis.Therefore,exploring these risk factors will help prevent it.AIM To investigate the relationships among serum glucagon-like peptide-1(GLP-1)levels,matrix Gla protein(MGP)levels,and diabetes with osteoporosis.METHODS Sixty patients with T2DM complicated with osteoporosis confirmed by the endocrinology department of our hospital were selected as the case group.Sixty T2DM patients with bone loss were selected as the control group.Sixty healthy participants were selected as the healthy group.The general data,bone mineral density index,and bone metabolic markers of the three groups were compared.The relationships among GLP-1 levels,MGP levels,and the bone mineral density index of the case group were analyzed using linear correlation analysis and a logistic regression model.RESULTS Differences in sex,smoking,and drinking among the case group,control group,and healthy group were not statistically significant(P>0.05).The mean age of the case group was older than those of the control and healthy groups(P<0.05).The body mass index,fasting plasma glucose level,HbA1c level,hypertension rate,and coronary heart disease rate of the case and control groups were higher than those of the healthy group(P<0.05).The serum GLP-1 and MGP levels of the case group were lower than those of the control and healthy groups;these differences were statistically significant(P<0.05).The serum GLP-1 and MGP levels of the control group were lower than those of the healthy group;these differences were statistically significant(P<0.05).The serum GLP-1 and MGP levels of the case group were significantly positively correlated with the bone mineral density values of the hip and lumbar spine(P<0.05).The results of the logistic regression model showed that age and duration of diabetes were independent risk factors for osteoporosis in diabetic patients(P<0.05)and that increased GLP-1 and MGP values were protective factors against osteoporosis in diabetic patients(P<0.05).CONCLUSION Serum GLP-1 and MGP levels of diabetic patients with osteoporosis were significantly decreased and positively correlated with bone mineral density and were independent risk factors for osteoporosis in diabetic patients.

Glucagon-like peptide-1 receptor agonists in non-alcoholic fatty liver disease: An update

Non-alcoholic fatty liver disease(NAFLD)is the predominant cause of chronic liver disease worldwide.NAFLD progresses in some cases to non-alcoholic steatohepatitis(NASH),which is characterized,in addition to liver fat deposition,by hepatocyte ballooning,inflammation and liver fibrosis,and in some cases may lead to hepatocellular carcinoma.NAFLD prevalence increases along with the rising incidence of type 2 diabetes mellitus(T2DM).Currently,lifestyle interventions and weight loss are used as the major therapeutic strategy in the vast majority of patients with NAFLD.Glucagon-like peptide-1 receptor agonists(GLP-1RAs)are used in the management of T2DM and do not have major side effects like hypoglycemia.In patients with NAFLD,the GLP-1 receptor production is down-regulated.Recently,several animal and human studies have emphasized the role of GLP-1RAs in ameliorating liver fat accumulation,alleviating the inflammatory environment and preventing NAFLD progression to NASH.In this review,we summarize the updated literature data on the beneficial effects of GLP-1RAs in NAFLD/NASH.Finally,as GLP-1RAs seem to be an attractive therapeutic option for T2DM patients with concomitant NAFLD,we discuss whether GLP-1RAs should represent the first line pharmacotherapy for these patients.

Uncoupling protein 2 regulates glucagon-like peptide-1 secretion in L-cells

AIM:To investigate whether uncoupling protein 2(UCP2) affects oleic acid-induced secretion of glucagonlike peptide-1(GLP-1) in L-cells.METHODS:mRNA and protein expression of UCP2 were analyzed in human NCI-H716 cells,which serve as a model for enteroendocrine L-cells,by quantitative reverse transcription-polymerase chain reaction and Western blotting before and after treatment with oleic acid.Localization of UCP2 and GLP-1 in NCI-H716 cells was assessed by immunofluorescence labeling.NCI-H716 cells were transiently transfected with a small interfering RNA(siRNA) that targets UCP2(siUCP2) or with a nonspecific siRNA using Lipofectamine 2000.The concentrations of bioactive GLP-1 in the medium were measured by enzyme linked immunosorbent assay.RESULTS:Both GLP-1 and UCP2 granules were expressed mainly in the cytoplasm of NCI-H716 cells.NCI-H716 cells that secreted GLP-1 also expressed UCP2.Time-course experiments revealed that release of GLP-1 from NCI-H716 cells into the medium reached a maximum at 120 min and remained stable until at least 180 min after treatment with oleic acid(the level of GLP-1 increased about 2.3-fold as compared with the level of GLP-1 in the control cells,P < 0.05).In an experiment to determine dose dependence,stimulation of NCI-H716 cells with ≤ 8 mmol oleic acid led to a concentration-dependent release of GLP-1 into the medium;10 mmol oleic acid diminished the release of GLP-1.Furthermore,GLP-1 secretion induced by oleic acid from NCI-H716 cells that were transfected with siUCP2 decreased to 41.8%,as compared with NCI-H716 cells that were transfected with a non-specific siRNA(P < 0.01).CONCLUSION:UCP2 affected GLP-1 secretion induced by oleic acid.UCP2 plays an important role in L-cell secretion that is induced by free fatty acids.

Is there a role for glucagon-like peptide-1 receptor agonists in the management of diabetic nephropathy?

Chronic kidney disease constitutes a major microvascular complication of diabetes mellitus.Accumulating data suggest that glucagon-like peptide-1 receptor agonists(GLP-1 RAs)might have a role in the management of diabetic kidney disease(DKD).GLP-1 RAs appear to reduce the incidence of persistent macro-albuminuria in patients with type 2 diabetes mellitus.This beneficial effect appears to be mediated not only by the glucose-lowering action of these agents but also on their blood pressure lowering,anti-inflammatory and antioxidant effects.On the other hand,GLP-1 RAs do not appear to affect the rate of decline of glomerular filtration rate.However,this might be due to the relatively short duration of the trials that evaluated their effects on DKD.Moreover,these trials were not designed nor powered to assess renal outcomes.Given than macrolbuminuria is a strong risk factor for the progression of DKD,it might be expected that GLP-1 RAs will prevent the deterioration in renal function in the long term.Nevertheless,this remains to be shown in appropriately designed randomized controlled trials in patients with DKD.

Correlation between gut microbiota and glucagon-like peptide-1 in patients with gestational diabetes mellitus

BACKGROUND Gestational diabetes mellitus(GDM)places both the mother and offspring at high risk of complications.Increasing evidence suggests that the gut microbiota plays a role in the pathogenesis of GDM.However,it is still unclear whether the gut microbiota is related to blood biochemical traits,particularly glucagon-like peptide-1(GLP-1),in GDM patients.AIM To explore the correlation between the gut microbiota and blood biochemical traits,particularly GLP-1,in GDM patients.METHODS The V4 region of the 16S ribosomal ribonucleic acid(rRNA)gene was sequenced based on the fecal samples of 35 pregnant women with GDM and was compared to that of 25 pregnant women with normal glucose tolerance(NGT).RESULTS The results showed that Ruminococcaceae_UCG-002,Ruminococcaceae_UCG-005,Clostridium_sensu_stricto_1,and Streptococcus were more abundant in the NGT group than in the GDM group.Bacteroides and Lachnoclostridium were more abundant in the GDM group than in the NGT group.Spearman’s correlation analysis was performed to identify the relationships between microbiota genera and blood biochemical traits.Paraprevotella,Roseburia,Faecalibacterium,and Ruminococcaceae_UCG-002 were significantly negatively correlated with glucose.Ruminococcaceae_UCG-002 was significantly negatively correlated with hemoglobin A1c.Bacteroides was significantly positively correlated with glucose.Sutterella,Oscillibacter,and Bifidobacterium were significantly positively correlated with GLP-1.A random forest model showed that 20 specific genera plus glucose provided the best discriminatory power,as indicated by the area under the receiver operating characteristic curve(0.94).CONCLUSION The results of this study reveal novel relationships between the gut microbiome,blood biochemical traits,particularly GLP-1,and GDM status.These findings suggest that some genera are crucial for controlling blood glucose-related indices and may be beneficial for GDM treatment.Alteration in the microbial composition of the gut may potentially serve as a marker for identifying individuals at risk of GDM.