Glucagon-Like Peptide Receptor Agonist Inhibits Angiotensin II-Induced Proliferation and Migration in Vascular Smooth Muscle Cells and Ameliorates Phosphate-Induced Vascular Smooth Muscle Cells Calcification.

BACKGRUOUND: Glucagon-like peptide-1 receptor agonist (GLP-1RA), which is a therapeutic agent for the treatment of type 2 diabetes mellitus, has a beneficial effect on the cardiovascular system. METHODS: To examine the protective effects of GLP-1RAs on proliferation and migration of vascular smooth muscle cells (VSMCs), A-10 cells exposed to angiotensin II (Ang II) were treated with either exendin-4, liraglutide, or dulaglutide. To examine the effects of GLP-1RAs on vascular calcification, cells exposed to high concentration of inorganic phosphate (Pi) were treated with exendin-4, liraglutide, or dulaglutide. RESULTS: Ang II increased proliferation and migration of VSMCs, gene expression levels of Ang II receptors AT1 and AT2, proliferation marker of proliferation Ki-67 (Mki-67), proliferating cell nuclear antigen (Pcna), and cyclin D1 (Ccnd1), and the protein expression levels of phospho-extracellular signal-regulated kinase (p-Erk), phospho-c-JUN N-terminal kinase (p-JNK), and phospho-phosphatidylinositol 3-kinase (p-Pi3k). Exendin-4, liraglutide, and dulaglutide significantly decreased the proliferation and migration of VSMCs, the gene expression levels of Pcna, and the protein expression levels of p-Erk and p-JNK in the Ang II-treated VSMCs. Erk inhibitor PD98059 and JNK inhibitor SP600125 decreased the protein expression levels of Pcna and Ccnd1 and proliferation of VSMCs. Inhibition of GLP-1R by siRNA reversed the reduction of the protein expression levels of p-Erk and p-JNK by exendin-4, liraglutide, and dulaglutide in the Ang II-treated VSMCs. Moreover, GLP-1 (9-36) amide also decreased the proliferation and migration of the Ang II-treated VSMCs. In addition, these GLP-1RAs decreased calcium deposition by inhibiting activating transcription factor 4 (Atf4) in Pi-treated VSMCs. CONCLUSION: These data show that GLP-1RAs ameliorate aberrant proliferation and migration in VSMCs through both GLP-1Rdependent and independent pathways and inhibit Pi-induced vascular calcification.

At ObesityWeek, More Data and Questions About Semaglutide, Tirzepatide, and Retatrutide.

This Medical News article discusses weight-loss medications highlighted at ObesityWeek 2023.

[Efficacy of treatment with glucagon-like peptide receptor agonists-1 in Asian patients with type 2 diabetes mellitus].

BACKGROUND: The projected 68% increase in patients with type 2 diabetes mellitus (T2D) in the upcoming decades and the specific pathophysiological course of the disease are critical factors for the development of optimal disease management tactics in the Asian population. It is now known that ß-cell dysfunction is dominant in the pathogenesis of T2D in Asians. In a number of Asian countries, incretin therapy is the leading therapy. AIM: To review literature on glucagon-like peptide-1 (GLP-1) secretion and clinical trial results of GLP-1 receptor agonist class (GLP-1RA) drugs as well as to evaluate their effectiveness in Asian population with T2D. MATERIALS AND METHODS: A review of studies on pathophysiological aspects of GLP-1 secretion and evaluation of the efficacy of therapy with GLP-1RA preparations registered and used in clinical practice in Asian regions. RESULTS: Several studies in Asian countries have shown that intact GLP-1 levels were significantly lower in both T2D patients and healthy Japanese volunteers; as well as in patients with impaired glucose tolerance. It is suggested that either impaired secretion of GLP-1 in the gut, accelerated processing by dipeptidyl peptidase-4, or a combination of both are responsible for the decrease in GLP-1. The greater efficacy of GLP-1RA treatment in achieving glycemic control in Asian T2D patients was presented by Kim Y.G. et al. in a meta-analysis of 15 randomised controlled trials, the reduction in HbA1c on GLP-1RA treatment averaged -1.16% in Asian-dominated studies and -0.83% in non-Asian-dominated studies. In the PIONEER 9 clinical programme, similar results were obtained, with oral semaglutide having a more pronounced effect on glycaemic control in Japanese patients. Thus, the mean change in HbA 1c was -1.1%, 7 mg -1.5%, and 14 mg -1.7% at the 3 mg dose; whereas in the PIONEER 1 study in the global population, the mean change in HbA1c was -0.6%, -0.9% and -1.1% for 3, 7, 14 mg semaglutide, respectively. The PIONEER 10 study concluded that oral semaglutide was well tolerated by Japanese patients with T2D. Oral semaglutide reduced HbA1c (14 mg dose) and body weight (7 and 14 mg doses) more significantly compared to dulaglutide at 0.75 mg dose. Results of a pooled analysis of long-acting GLP-1RA showed a more significant reduction in cardiovascular event risk in the Asian subpopulation. CONCLUSION: The presented review describes benefits in glycemic control as well as in the reduction of relative cardiovascular event risks with GLP-1RA treatment in the Asian population, which requires further in-depth research and implies optimal management tactics in patients with T2DM.

The incretin co-agonist tirzepatide requires GIPR for hormone secretion from human islets.

The incretins glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) mediate insulin responses that are proportionate to nutrient intake to facilitate glucose tolerance1. The GLP-1 receptor (GLP-1R) is an established drug target for the treatment of diabetes and obesity2, whereas the therapeutic potential of the GIP receptor (GIPR) is a subject of debate. Tirzepatide is an agonist at both the GIPR and GLP-1R and is a highly effective treatment for type 2 diabetes and obesity3,4. However, although tirzepatide activates GIPR in cell lines and mouse models, it is not clear whether or how dual agonism contributes to its therapeutic benefit. Islet beta cells express both the GLP-1R and the GIPR, and insulin secretion is an established mechanism by which incretin agonists improve glycemic control5. Here, we show that in mouse islets, tirzepatide stimulates insulin secretion predominantly through the GLP-1R, owing to reduced potency at the mouse GIPR. However, in human islets, antagonizing GIPR activity consistently decreases the insulin response to tirzepatide. Moreover, tirzepatide enhances glucagon secretion and somatostatin secretion in human islets. These data demonstrate that tirzepatide stimulates islet hormone secretion from human islets through both incretin receptors.

Eosinophil-related diseases during treatment with glucagon-like peptide one receptor (GLP-1 RA): a case report and review of the literature.

Glucagon-like peptide one-receptor agonists (GLP-1 RA) are drugs that differ in their pharmacological composition and homology to human GLP-1 and are used most frequently for the treatment of type 2 diabetes and weight loss. There are isolated reports of eosinophilic adverse reactions associated with GLP-1 RA. We present the case of a 42-year-old female patient who, after starting weekly subcutaneous semaglutide, developed eosinophilic fasciitis with favorable clinical evolution after the discontinuation of semaglutide and the initiation of immunosuppression. A review of the eosinophilic adverse events that have been previously reported with GLP-1 RA is provided.

Direct comparison two fixed-ratio combination glucagon-like peptide receptor agonist and basal insulin on glycemic and non glycemic parameters in type 2 diabetes.

BACKGROUND: Two types of fixed-ratio combinations of basal insulin and a glucagon-like peptide-1 receptor agonist (GLP-1RA) have been approved for use in type 2 diabetes. One is insulin degludec/liraglutide (iDergLira), and the other is insulin glargine/lixisenatide (iGlarLixi). Direct comparisons between these two combination is not available. METHODS: The retrospective study included 186 patients with type 2 diabetes mellitus (DM) with inadequate glycemic control on metformin and basal insulin (degludec, glargine 100, glargine 300) who were switched to fixed-ratio combination GLP-1 RA and basal insulin. Patients were divided into two groups based on the basal insulin before study: group I (n = 86) treated with degludec were switched to iDegLira and patients group II (n = 99), treated with glargine were switched to iGlarLixi. The aim of this study was to directly compare the effects between two fixed - ratio combination on glycemic parameters and non glycemic parameters. Follow up was 6 months. RESULTS: Mean HbA1c decreased similarly (- 1.2% vs.-1.1%). Higher percentage patients in iDegLira group had reached the HbA1c < 7% after 6 months (22% vs. 18.2%, p < 0.05). The mean change in fasting plasma glucose (FPG) was comparable for the two groups, while mean decrease postprandial plasma glucose (PPG) level were lower in iGlarLixi group (2 vs 1.8 mmol/l, p > 0.05). Change in body weight was significant in iDegLira group (1.8 kg vs. 0.7 kg, p < 0.001). At the end of the study patients showed decrease in total cholesterol (TC) and low-density lipoprotein (LDL) for 0.2 mmol/L in iDegLira, 0.1 mmol/l in iGlarLixi, triglycerides decreased 0.3 mmol/l in both groups, high-density lipoprotein(HDL) increased 0.1 mm/l in iGlarLixi. CONCLUSION: Our results showed that more patients with iDegLira had HbA1c less than 7% and these combination had better effect on weight loss. There was no difference observed in FPG and PPG, lipid profile and rate of hypoglycemia.

Obesity-related vascular dysfunction persists after weight loss and is associated with decreased vascular glucagon-like peptide receptor in female rats.

Obesity-related cardiovascular complications are a major health problem worldwide. Overconsumption of the Western diet is a well-known culprit for the development of obesity. Although short-term weight loss through switching from a Western diet to a normal diet is known to promote metabolic improvement, its short-term effects on vascular parameters are not well characterized. Glucagon-like peptide 1 (GLP-1), an incretin with vasculoprotective properties, is decreased in plasma from patients who are obese. We hypothesize that obesity causes persistent vascular dysfunction in association with the downregulation of vascular glucagon-like peptide 1 receptor (GLP-1R). Female Wistar rats were randomized into three groups: lean received a chow diet for 28 wk, obese received a Western diet for 28 wk, and reverse obese received a Western diet for 18 wk followed by 12 wk of standard chow diet. The obese group exhibited increased body weight and body mass index, whereas the reverse obese group lost weight. Weight loss failed to reverse impaired vasodilation and high systolic blood pressure in obese rats. Strikingly, our results show that obese rats exhibit decreased serum levels of GLP-1 accompanied by decreased vascular GLP-1R expression. Weight loss recovered GLP-1 serum levels, however GLP-1R expression remained downregulated. Decreased Akt phosphorylation was observed in the obese and reverse obese group, suggesting that GLP-1/Akt signaling is persistently downregulated. Our results support that GLP-1 signaling is associated with obesity-related vascular dysfunction in females, and short-term weight loss does not guarantee recovery of vascular function. This study suggests that GLP-1R may be a potential target for therapeutic intervention in obesity-related hypertension in females.NEW & NOTEWORTHY Although short-term weight loss successfully improved metabolic parameters, it failed to correct vascular dysfunction present in obese female rats. Vascular GLP-1/Akt signaling was decreased in both obese rats and those with short-term weight loss, suggesting it may be a potential target for therapeutic intervention in obesity-related persistent vascular dysfunction in obese females.

Sleeve Gastrectomy Improves High-Fat Diet-Associated Hepatic Steatosis Independent of the Glucagon-like-Petpide-1 Receptor in Rats.

BACKGROUND: The gastrointestinal hormone glucagon-like peptide-1 (GLP-1) is increased after sleeve gastrectomy (SG). Rat and clinical studies support, while mouse studies refute, a role for GLP-1R signaling after SG. Therefore, we developed a global GLP-1R knockout (KO) rat to test the hypothesis that a functional GLP-1R is critical to induce weight loss and metabolic disease improvement after SG. METHODOLOGY: A 4 bp deletion was created in exon 2 of the GLP-1R gene on a Lewis strain background to create a global GLP-1R KO rat. KO and Lewis rats were placed on a high-fat or low-fat diet and phenotyped followed by SG or Sham surgery and assessed for the effect of GLP-1R KO on surgical and metabolic efficacy. RESULTS: Loss of the GLP-1R created an obesity-prone rodent without changes in energy expenditure. Both male and female KO rats had significantly greater insulin concentrations after an oral glucose gavage, augmented by a high-fat diet, compared to Lewis rats despite similar glucose concentrations. GLP-1R KO caused hepatomegaly and increased triglyceride deposition compared to Lewis rats. We found no difference between SG GLP-1R KO and Lewis groups when considering efficacy on body weight, glucose tolerance, and a robustly preserved improvement in fatty liver disease. CONCLUSIONS: Loss of the GLP-1R in rats resulted in increased adiposity, insulin resistance, and severe steatosis. A functional GLP-1R is not critical to the metabolic efficacy of SG in Lewis rats, similar to mouse studies, but importantly including steatosis, supporting a GLP-1R-independent mechanism for the improvement in fatty liver disease after SG.

GLP2-GLP2R signal affects the viability and EGFR-TKIs sensitivity of PC9 and HCC827 cells.

BACKGROUND: The resistance to epidermal growth factor receptor (EGFR)- tyrosine kinase inhibitors (TKIs) therapy is currently the major clinical challenge in the treatment of lung cancer. This study aims to reveal the role of glucagon-like peptide (GLP) 2 and GLP-2 receptor (GLP2R) signaling on the EGFR-TKIs and cisplatin resistance of lung cancer cells. METHODS: The common differentially expressed genes in PC9 and HCC827 cells that were individually resistant to one of the three EGFR-TKIs (dacomitinib, osimertinib and afatinib) were screened. The data were from GSE168043 and GSE163913. The expression of GLP2R in drug-resistant cells was detected by western blot. The effect of GLP2R expression down- or up-regulation on resistance to dacomitinib, osimertinib, afatinib or cisplatin was measured by CCK-8 and flow cytometry assays. The long-acting analog of GLP-2, teduglutide, treated the parental cells. RESULTS: A total of 143 common differentially expressed genes were identified. Compared with the parent cells, the GLP2R expression in drug-resistant cell lines was significantly up-regulated. The exogenous expression of GLP2R in parental cells enhanced cell viability, while knockdown of GLP2R levels in drug-resistant cell lines inhibited cell viability. In addition, teduglutide treatment also enhanced the viability of lung cancer cells. CONCLUSION: GLP2-GLP2R signal may change the sensitivity of cells to EGFR-TKIs and cisplatin. The development of GLP-2 or GLP2R inhibitors may be beneficial to the clinical treatment of lung cancer.

Divergent Effect of Central Incretin Receptors Inhibition in a Rat Model of Sporadic Alzheimer's Disease.

The incretin system is an emerging new field that might provide valuable contributions to the research of both the pathophysiology and therapeutic strategies in the treatment of diabetes, obesity, and neurodegenerative disorders. This study aimed to explore the roles of central glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP) on cell metabolism and energy in the brain, as well as on the levels of these incretins, insulin, and glucose via inhibition of the central incretin receptors following intracerebroventricular administration of the respective antagonists in healthy rats and a streptozotocin-induced rat model of sporadic Alzheimer's disease (sAD). Chemical ablation of the central GIP receptor (GIPR) or GLP-1 receptor (GLP-1R) in healthy and diseased animals indicated a region-dependent role of incretins in brain cell energy and metabolism and central incretin-dependent modulation of peripheral hormone secretion, markedly after GIPR inhibition, as well as a dysregulation of the GLP-1 system in experimental sAD.

Comparison of Sodium-Glucose Cotransporter 2 Inhibitors and Glucagon-like Peptide Receptor Agonists for Atrial Fibrillation in Type 2 Diabetes Mellitus: Systematic Review With Network Meta-analysis of Randomized Controlled Trials.

ABSTRACT: Atrial fibrillation (AF) is a major public health concern with a rising prevalence. Although sodium-glucose cotransporter 2 inhibitors (SGLT2is) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) have shown the respective favorable effects on reducing the occurrence of AF/atrial flutter (AFL), comparative protective AF/AFL effects between above 2 novel antidiabetic agents remain unavailable. Thus, we aimed to evaluate the comparative efficacy of SGLT2is and GLP-1RAs in reducing the risk of AF/AFL in patients with type 2 diabetes and estimate relative rankings of interventions. PubMed, Embase, and ClinicalTrials.gov were searched up to December 1, 2020. All available randomized controlled trials comparing SGLT2is and GLP-1RAs with one another or placebo in patients with type 2 diabetes were included. Pooled results were shown as risk ratios (RRs) with 95% confidence intervals (CIs). We used a frequentist network meta-analysis to evaluate the outcomes of interests. Thirty-six randomized controlled trials including 85,701 participants with type 2 diabetes were identified. Compared with placebo, both SGLT2is (RR: 0.82, 95% CI, 0.68-0.99) and GLP-1RAs (RR: 0.86, 95% CI, 0.76-0.97; RR long-acting ones: 0.87, 95% CI, 0.76-0.99; RR short-acting ones: 0.72, 95% CI, 0.45-1.14) significantly reduced AF/AFL risk. No significant difference between SGLT2is and GLP-1RAs was noted (RR: 0.95, 95% CI, 0.76-1.2). Compared with placebo, results from the analysis showed an RR of 0.72 (95% CI, 0.45-1.14) for short-acting GLP-1RAs and 0.87 (95% CI, 0.76-0.99) for long-acting GLP-1RAs in reducing the risk of AF/AFL. Compared with placebo, both SGLT2is and GLP-1RAs possessed favorable effects on reducing the risk of AF/AFL. However, no difference was observed when comparisons were made between them. In addition, long-acting ones may confer a more pronounced AF/AFL reduction benefit compared with placebo.

Incretins in the Therapy of Diabetic Kidney Disease.

Diabetic kidney disease is a microvascular complication that occurs in patients with diabetes. It is strongly associated with increased risk of kidney replacement therapy and all-cause mortality. Incretins are peptide hormones derived from the gastrointestinal tract, that besides causing enhancement of insulin secretion after oral glucose intake, participate in many other metabolic processes. Antidiabetic drug classes, such as dipeptidyl peptidase 4 inhibitors and glucagon-like peptide receptor agonists, which way of action is based on incretins facility, not only show glucose-lowering properties but also have nephroprotective functions. The aim of this article is to present the latest information about incretin-based therapy and its influence on diabetic kidney disease appearance and progression, point its potential mechanisms of kidney protection and focus on future therapeutic possibilities bound with these two antidiabetic drug classes.

Uso de terapia antihiperglucemiante con beneficio cardiovascular en pacientes con diabetes tipo 2 que requieren hospitalización: un estudio transversal / Use of antihyperglycaemic therapy with cardiovascular benefit in patients with type 2 diabetes who require hospitalisation: A cross-sectional study

Objetivo Evaluar el uso de la terapia con beneficio cardiovascular en pacientes con DM tipo 2 previo al ingreso en servicios de medicina interna. Métodos Estudio transversal en un día de los pacientes con DM tipo 2 hospitalizados en servicios de medicina interna. Se recogieron variables demográficas y antropométricas, datos de laboratorio y utilización de fármacos antihiperglucemiantes. La variable desenlace fue la proporción y los determinantes de uso de inhibidores del cotransportador sodio-glucosa 2 (iSGLT2) y de agonistas del receptor del péptido similar al glucagón tipo 1 (AR-GLP1). Resultados Se incluyeron 928 pacientes pertenecientes a 74 hospitales. La edad media fue 78,9 años (DE: 10,86), un 50% varones. Un total de 557 (60%) presentaba cardiopatía isquémica, 189 (20,4%) enfermedad cerebrovascular, 293 (31,6%) insuficiencia cardiaca, 274 (29,5%) enfermedad renal crónica y 129 (13,9%) enfermedad arterial periférica. Los antihiperglucemiantes utilizados previo al ingreso fueron: sulfonilureas (5.7%), biguanidas (49.1%), inhibidores de la alfa-glucosidasa (0,2%), pioglitazona (0%), iDPP4 (39%), iSGLT2 (5,8%), AR-GLP1 (2,6%) y análogos de insulina basal (24%). La edad mayor de 75 años fue el factor determinante principal para no utilizar iSGLT2 (OR ajustada 0,28; intervalo de confianza al 95%: 0,10-0,74; p=0,039) o AR-GLP1 (OR ajustada 0,09; intervalo de confianza al 95%: 0,02-0,46; p=0,006). Discusión Una gran proporción de pacientes ancianos con DM tipo 2 de muy alto riesgo cardiovascular no recibe terapia antihiperglucemiante con fármacos de probado beneficio cardiovascular. El tratamiento más frecuentemente utilizado fue metformina e iDPP4. Existe un margen de mejora en el tratamiento en esta población de muy alto riesgo (AU)

Objective To evaluate the use of therapy with cardiovascular benefit in patients with type 2 diabetes mellitus admitted to internal medicine departments. Methods One day, cross-sectional study of patients with type 2 diabetes mellitus hospitalised in internal medicine departments. We recorded demographic and anthropometric variables, laboratory data and use of antihyperglycaemic drugs. The endpoint was the proportion and determinants of the use of sodium-glucose cotransporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP1-RA). Results We included 928 patients belonging to 74 hospitals, with a mean age of 78.9 years (SD, 10.86 years), 50% of whom were men. A total of 557 (60%) patients had ischaemic heart disease, 189 (20.4%) had cerebrovascular disease, 293 (31.6%) had heart failure, 274 (29.5%) had chronic kidney disease, and 129 (13.9%) had peripheral arterial disease. Prior to their hospital admission, the patients were taking sulfonylureas (5.7%), biguanides (49.1%), alpha-glucosidase inhibitors (0.2%), pioglitazone (0%), dipeptidyl peptidase 4 inhibitors (39%), SGLT2i (5.8%), GLP1-RA (2.6%) and basal insulin analogues (24%). An age over 75 years was the main determinant for not taking SGLT2i (adjusted OR, 0.28; 95% CI 0.10-0.74; P=.039) or GLP1-RA (adjusted OR, 0.09; 95% CI 0.02-0.46; P=.006). Discussion A large proportion of elderly patients with type 2 diabetes mellitus at very high cardiovascular risk are not treated with antihyperglycemic drugs with proven cardiovascular benefit. The most commonly used drugs were metformin and DPP4i. There is room for improvement in the treatment of this very high-risk population (AU)

Predictive models for cardiovascular and kidney outcomes in patients with type 2 diabetes: systematic review and meta-analyses.

OBJECTIVE: To inform a clinical practice guideline (BMJ Rapid Recommendations) considering sodium glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists for treatment of adults with type 2 diabetes, we summarised the available evidence regarding the performance of validated risk models on cardiovascular and kidney outcomes in these patients. METHODS: We systematically searched bibliographic databases in January 2020 to identify observational studies evaluating risk models for all-cause and cardiovascular mortality, heart failure (HF) hospitalisations, end-stage kidney disease (ESKD), myocardial infarction (MI) and ischaemic stroke in ambulatory adults with type 2 diabetes. Using a random effects model, we pooled discrimination measures for each model and outcome, separately, and descriptively summarised calibration plots, when available. We used the Prediction Model Risk of Bias Assessment Tool to assess risk of bias of each included study and the Grading of Recommendations, Assessment, Development, and Evaluation approach to evaluate our certainty in the evidence. RESULTS: Of 22 589 publications identified, 15 observational studies reporting on seven risk models proved eligible. Among the seven models with >1 validation cohort, the Risk Equations for Complications of Type 2 Diabetes (RECODe) had the best calibration in primary studies and the highest pooled discrimination measures for the following outcomes: all-cause mortality (C-statistics 0.75, 95% CI 0.70 to 0.80; high certainty), cardiovascular mortality (0.79, 95% CI 0.75 to 0.84; low certainty), ESKD (0.73, 95% CI 0.52 to 0.94; low certainty), MI (0.72, 95% CI 0.69 to 0.74; moderate certainty) and stroke (0.71, 95% CI 0.68 to 0.74; moderate certainty). This model does not, however, predict risk of HF hospitalisations. CONCLUSION: Of available risk models, RECODe proved to have satisfactory calibration in primary validation studies and acceptable discrimination superior to other models, though with high risk of bias in most primary studies. TRIAL REGISTRATION NUMBER: CRD42020168351.

Exendin-4, a glucagon-like peptide receptor agonist, facilitates osteoblast differentiation via connexin43.

PURPOSE: To investigate whether exendin-4 (Ex-4), a glucagon-like peptide 1 receptor (GLP-1R) agonist, affects connexin 43 (Cx43) expression in osteoblasts, and determine the specific mechanism underlying Cx43 modulation by Ex-4. METHODS: Osteoblast-like MC3T3-E1 cells were treated with Ex-4 with or without GLP-1R antagonist. We assessed Cx43 expression using RT-PCR, western blotting, and confocal microscopy; visualized intercellular communication using Lucifer yellow dye transfer assay; evaluated osteoblast differentiation using alkaline phosphatase and Alizarin red S (ARS) staining. Cx43 silencing or overexpression was investigated via RNA-interference or adenovirus infection. The mechanism underlying Cx43 regulation by Ex-4 was determined via treatment with either Src kinase inhibitor, KX2-391, Akt activator, sc79, or inhibitor, LY294002. RESULTS: Ex-4 treatment enhanced Cx43 expression and gap junctional intercellular communication in MC3T3-E1 cells. GLP-1R antagonist pretreatment abrogated the induction of Cx43 expression. Cx43 silencing significantly decreased ARS staining intensity in Ex-4-treated cells, whereas overexpression enhanced cell differentiation. Treatment with KX2-391 reduced both the Ex-4-induced increase of Cx43 expression and p-Akt protein levels. sc79 upregulated Cx43 expression, while LY294002 attenuated Cx43 upregulation by Ex-4. CONCLUSIONS: Induced Cx43 expression in osteoblasts via the Src-Akt signaling pathway illustrates the underlying mechanism for promoting osteoblast differentiation by Ex-4.

The Role of Hypothalamic Inflammation in Diet-Induced Obesity and Its Association with Cognitive and Mood Disorders.

Obesity is often associated with cognitive and mood disorders. Recent evidence suggests that obesity may cause hypothalamic inflammation. Our aim was to investigate the hypothesis that there is a causal link between obesity-induced hypothalamic inflammation and cognitive and mood disorders. Inflammation may influence hypothalamic inter-connections with regions important for cognition and mood, while it may cause dysregulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis and influence monoaminergic systems. Exercise, healthy diet, and glucagon-like peptide receptor agonists, which can reduce hypothalamic inflammation in obese models, could improve the deleterious effects on cognition and mood.

Semaglutide: A Novel Oral Glucagon-Like Peptide Receptor Agonist for the Treatment of Type 2 Diabetes Mellitus.

Diabetes mellitus (DM) is a complex and chronic condition that requires continuous medical care. Uncontrolled hyperglycemia can lead to serious microvascular and macrovascular complications, such as coronary artery disease, peripheral arterial disease, and stroke. Type 2 DM occurs when the pancreas is unable to produce adequate insulin to regulate glucose levels and when there is a decrease in sensitivity to insulin in the body. Insufficient glucagon-like peptide (GLP-1), a normal body hormone, plays an important role in the pathophysiology of DM. The introduction of the GLP-1 receptor agonists expanded therapeutic options in achieving glycemic control in adult patients. In 2005, the US Food and Drug Administration approved exenatide as the first injectable formulation, which led to the advancement of other injectable formulations within the class of GLP-1 receptor agonists. In 2019, semaglutide was approved as the first oral GLP-1 receptor agonist addressing the unmet needs in patients who benefit from therapy with this therapeutic class yet are unwilling to use an injectable drug. This article will provide an overview of the GLP-1 receptor agonists, including the pharmacology of semaglutide, its clinical evidence and role in therapy in type 2 DM.

Systematic Review of Glucagon-Like Peptide One Receptor Agonist Liraglutide of Subjects with Heart Failure with Reduced Left Ventricular Ejection Fraction.

BACKGROUND: The major cardiovascular outcome trials on glucagon-like peptide one-receptor agonists have examined its effect on hospitalization of subjects with heart failure; however, very limited trials have been conducted on subjects with reduced left ventricular ejection fraction (r- LVEF) as a primary outcome. OBJECTIVE: We have conducted a systematic review of two major (FIGHT and LIVE) placebo-controlled trials of liraglutide and its clinical effect on the ejection fraction of subjects with heart failure. METHODS: Medline data was retrieved for trials involving liraglutide from 2012 to 2020. The inclusion criteria for trials were: subjects with or without type 2 diabetes mellitus (T2DM), subjects with heart failure with rLVEF, major trials (phase II or III) on liraglutide, trials included liraglutide with defined efficacy primary outcome of patients with heart failure with rLVEF. The search was limited to the English language, whereby two trials [FIGHT and LIVE] had been included and two trials were excluded due to different primary outcomes. Participants (541) had been randomized for either liraglutide or placebo for 24 weeks. RESULTS: In the FIGHT trial the primary intention-to-treat, sensitivity, and diabetes subgroup analyses have shown no significant between-group difference in the global rank scores (mean rank of 146 in the liraglutide group versus 156 in the placebo group; Wilcoxon rank-sum P=.31), number of deaths, re-hospitalizations for heart failure, or the composite of death or change in NT-pro BNP level (P= .94). In the LIVE trial, the change in the left ventricular ejection fraction (LVEF) from baseline to week 24 was not significantly different between treatment groups. The overall discontinuation rate of liraglutide was high in the FIGHT trial (29%, 86) as compared to that in the LIVE trial (11.6%, 28). CONCLUSION: FIGHT and LIVE trials have demonstrated that liraglutide use in subjects with heart failure and rLVEF was implicated with an increased adverse risk of heart failure-related outcomes.