Effect of GLP-1 mimetics on blood pressure and relationship to weight loss and glycemia lowering: results of a systematic meta-analysis and meta-regression

Emerging therapeutic landscape: Incretin agonists in chronic kidney disease management

The increasing incidence of chronic kidney disease (CKD) poses a significant public health concern, prompting heightened attention to its treatment. Incretins, including glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide, are intestinal peptides released after nutrient intake, known for their hypoglycemic effects in diabetes management. Recent advancements highlight the promising outcomes of GLP-1 receptor agonists in reducing CKD risk factors and improving renal outcomes. The multifaceted functions of GLP-1, such as its anti-obesity, anti-hypertensive, anti-hyperglycemic, anti-lipid, anti-inflammatory, and endothelial function protective properties, contribute to its potential as a therapeutic agent for CKD. Although experiments suggest the potential benefits of incretin in CKD, a comprehensive understanding of its specific mechanisms is still lacking. This review aims to provide a detailed examination of current evidence and potential future directions, emphasizing the promising yet evolving landscape of incretin agonists in the context of CKD.

Practice Patterns and Perspectives of the Off-Label Use of GLP-1 Agonists for Cosmetic Weight Loss

BACKGROUND

The off-label use of glucagon-like peptide 1 (GLP-1) agonists for cosmetic weight loss has captured the interest of the public. However, there is a paucity of published data on their utilization, implications, and management, particularly in the plastic surgery community.

OBJECTIVES

This study aims to explore the current practice patterns of aesthetic plastic surgeons regarding the off-label implementation of GLP-1 agonists.

METHODS

A 35-question survey was sent to the 2600 members of The Aesthetic Society in July 2023. The survey collected physician demographics, practice settings, patient population demographics, and the use and management of GLP-1 agonists in their practice. No identifying variables were collected; all responses were anonymous.

RESULTS

A total of 368 respondents were included. A quarter of respondents (25.3%) prescribed or utilized GLP-1 agonists in their practice. Nearly a third (29.9%) reported personal use of the medication, of which 71 (70.3%) indicated it was for cosmetic weight loss. Many aspects of the current treatment, counseling, and follow-up practices were similar among prescribing plastic surgeons. However, there were discrepancies in screening, nutrition counseling, and perioperative management. The majority believed that GLP-1 agonists were effective for weight loss (68.9%), profitable for business (57.8%), and would recommend its implementation to other plastic surgeons (68.5%).

CONCLUSIONS

As leaders in the aesthetic field, it behooves plastic surgeons to take charge of shaping public opinion surrounding the growing off-label use of GLP-1 agonists for cosmetic weight loss. Plastic surgeons' leadership is imperative in establishing safe and ethical guidelines and protocols for proper screening, management, and patient care.

LEVEL OF EVIDENCE: 4

The impact of GLP-1 receptor agonist liraglutide on blood pressure profile, hydration, natriuresis in diabetic patients with severely impaired kidney function

Chronic treatment with GLP-1R agonists may moderately lower blood pressure due to increased natriuresis and RAAS inhibition. Short-term effect of these drugs on blood pressure may be opposite and its mechanism remains unclear. We investigated the effect of a single dose of liraglutide on diurnal blood pressure profile, natriuresis, hydration and serum concentration of renin, aldosterone and atrial natriuretic peptide (ANP) in diabetic kidney disease (DKD). 17 patients with eGFR < 30 ml/min/1.73 m2 and 17 with > 60 ml/min/1.73 m2 received in a random order a single subcutaneous dose 1.2 mg liraglutide and placebo with subsequent 24 h blood pressure and natriuresis monitoring. Before and after each medication thoracic fluid index and plasma renin, aldosterone and ANP were also assessed. The blood pressure load in the daytime and nighttime were significantly increased after liraglutide compared to placebo in patients with eGFR < 30 ml/min/1.73 m2. In patients with eGFR > 60 ml/min/1.73 m2 the changes of arterial pressure were comparable, while the morning surge was significantly reduced after liraglutide compared to placebo. After liraglutide 24 h urine sodium excretion increased in both groups vs. placebo (p < 0.001), the effect was greatest in subjects with eGFR > 60 ml/min/1.73 m2. Plasma ANP increased after liraglutide in both groups, most in patients with eGFR < 30 ml/min/1.73 m2 group. Plasma aldosterone (p = 0.013) and thoracic fluid index (p = 0.01) decreased after liraglutide compared to placebo (p = 0.013 and p + 0.01, respectively. Plasma renin concentration remained unchanged. In severe chronic kidney disease liraglutide induces a transient increase of blood pressure due to reduced natriuresis. The natriuretic effect of liraglutide in DKD may be related to increased ANP and decreased aldosterone secretion.

Metabolic-Dysfunction-Associated Steatotic Liver Disease-Its Pathophysiology, Association with Atherosclerosis and Cardiovascular Disease, and Treatments

Metabolic-dysfunction-associated steatotic liver disease (MASLD) is a chronic liver disease that affects more than a quarter of the global population and whose prevalence is increasing worldwide due to the pandemic of obesity. Obesity, impaired glucose metabolism, high blood pressure and atherogenic dyslipidemia are risk factors for MASLD. Therefore, insulin resistance may be closely associated with the development and progression of MASLD. Hepatic entry of increased fatty acids released from adipose tissue, increase in fatty acid synthesis and reduced fatty acid oxidation in the liver and hepatic overproduction of triglyceride-rich lipoproteins may induce the development of MASLD. Since insulin resistance also induces atherosclerosis, the leading cause for death in MASLD patients is cardiovascular disease. Considering that the development of cardiovascular diseases determines the prognosis of MASLD patients, the therapeutic interventions for MASLD should reduce body weight and improve coronary risk factors, in addition to an improving in liver function. Lifestyle modifications, such as improved diet and increased exercise, and surgical interventions, such as bariatric surgery and intragastric balloons, have shown to improve MASLD by reducing body weight. Sodium glucose cotransporter 2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been shown to improve coronary risk factors and to suppress the occurrence of cardiovascular diseases. Both SGLT2i and GLP-1 have been reported to improve liver enzymes, hepatic steatosis and fibrosis. We recently reported that the selective peroxisome proliferator-activated receptor-alpha (PPARα) modulator pemafibrate improved liver function. PPARα agonists have multiple anti-atherogenic properties. Here, we consider the pathophysiology of MASLD and the mechanisms of action of such drugs and whether such drugs and the combination therapy of such drugs could be the treatments for MASLD.

Acute kidney injury in diabetes mellitus: Epidemiology, diagnostic, and therapeutic concepts

Acute kidney injury (AKI) and diabetes mellitus (DM) are public health problems that cause a high socioeconomic burden worldwide. In recent years, the landscape of AKI etiology has shifted: Emerging evidence has demonstrated that DM is an independent risk factor for the onset of AKI, while an alternative perspective considers AKI as a bona fide complication of DM. Therefore, it is necessary to systematically characterize the features of AKI in DM. In this review, we summarized the epidemiology of AKI in DM. While focusing on circulation- and tissue-specific microenvironment changes after DM, we described the active cellular and molecular mechanisms of increased kidney susceptibility to AKI under DM stress. We also reviewed the current diagnostic and therapeutic strategies for AKI in DM recommended in the clinic. Updated recognition of the epidemiology, pathophysiology, diagnosis, and medications of AKI in DM is believed to reveal a path to mitigate the frequency of AKI and DM comorbidity that will ultimately improve the quality of life in DM patients.

Systolic blood pressure reduction with tirzepatide in patients with type 2 diabetes: insights from SURPASS clinical program

BACKGROUND

Tirzepatide, a once-weekly glucose-dependent insulinotropic polypeptide/ glucagon-like peptide-1 receptor agonist, is approved in the United States, Europe and Japan for the treatment of type 2 diabetes. Across the SURPASS-1 to -5 clinical studies, tirzepatide 5, 10 and 15 mg demonstrated significant improvements in glycated haemoglobin A1c (HbA1c) (- 1.9 to - 2.6%), body weight (- 6.6 to - 13.9%) and systolic blood pressure (SBP) (- 2.8 to - 12.6 mmHg) at the end of study treatment.

METHODS

Post-hoc mediation analyses were conducted to evaluate weight-loss dependent and weight-loss independent effects of tirzepatide on SBP reductions across the 5 SURPASS studies. The safety population (all randomized patients who took at least 1 dose of study drug) of each study was analyzed. Additional analyses were conducted at individual study level or pooled across 5 SURPASS trials.

RESULTS

The difference in mean SBP change from baseline at 40 weeks (total effect) between the tirzepatide and comparator groups was - 1.3 to - 5.1 mmHg (tirzepatide 5 mg), - 1.7 to - 6.5 mmHg (tirzepatide 10 mg) and - 3.1 to - 11.5 mmHg (tirzepatide 15 mg). These SBP reductions were primarily mediated through weight loss, with different degrees of contributions from weight-loss independent effects across the different trials. In the SURPASS-4 study, which enrolled patients with established cardiovascular disease, weight-loss independent effects explained 33% to 57% of difference in SBP change between tirzepatide and insulin glargine groups. In a pooled analysis of the SURPASS-1 to -5 studies, there was a significant (p < 0.001) but weak correlation (r = 0.18 to 0.22) between change in body weight and SBP. Reductions in SBP with tirzepatide were not dependent on concomitant antihypertensive medications at baseline as similar reductions were observed whether participants were receiving them or not (interaction p = 0.77). The largest SBP reductions were observed in the highest baseline category (> 140 mmHg), while those in the first quartile of baseline SBP category (< 122 mmHg) observed no further decrease in SBP.

CONCLUSIONS

Tirzepatide-induced SBP reduction was primarily mediated through weight loss, with different degrees of contributions from weight-loss independent effects across the different trials. SBP reduction was not dependent on antihypertensive medication use but dependent on baseline SBP value, alleviating theoretical concerns of hypotension.

Weight-dependent and weight-independent effects of dulaglutide on blood pressure in patients with type 2 diabetes

BACKGROUND

Patients with type 2 diabetes (T2D) treated with glucagon-like peptide-1 receptor agonists may experience reductions in weight and blood pressure. The primary objective of the current study was to determine the weight-dependent and weight-independent effects of ~ 6 months treatment with dulaglutide 1.5 mg treatment in participants with T2D.

METHODS

Mediation analysis was conducted for five randomized, placebo-controlled trials of dulaglutide 1.5 mg to estimate the weight-dependent (i.e., mediated by weight) and weight-independent effects from dulaglutide vs. placebo on change from baseline for systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure. A random-effects meta-analysis combined these results. To investigate a dose response between dulaglutide 4.5 mg and placebo, mediation analysis was first conducted in AWARD-11 to estimate the weight-dependent and weight-independent effects of dulaglutide 4.5 mg vs. 1.5 mg, followed by an indirect comparison with the mediation result for dulaglutide 1.5 mg vs. placebo.

RESULTS

Baseline characteristics were largely similar across the trials. In the mediation meta-analysis of placebo-controlled trials, the total treatment effect of dulaglutide 1.5 mg after placebo-adjustment on SBP was - 2.6 mmHg (95% CI - 3.8, - 1.5; p < 0.001) and was attributed to both a weight-dependent effect (- 0.9 mmHg; 95% CI: - 1.4, - 0.5; p < 0.001) and a weight-independent effect (- 1.5 mmHg; 95% CI: - 2.6, - 0.3; p = 0.01), accounting for 36% and 64% of the total effect, respectively. For pulse pressure, the total treatment effect of dulaglutide (- 2.5 mmHg; 95% CI: - 3.5, - 1.5; p < 0.001) was 14% weight-dependent and 86% weight-independent. For DBP there was limited impact of dulaglutide treatment, with only a small weight-mediated effect. Dulaglutide 4.5 mg demonstrated an effect on reduction in SBP and pulse pressure beyond that of dulaglutide 1.5 mg which was primarily weight mediated.

CONCLUSIONS

Dulaglutide 1.5 mg reduced SBP and pulse pressure in people with T2D across the placebo-controlled trials in the AWARD program. While up to one third of the effect of dulaglutide 1.5 mg on SBP and pulse pressure was due to weight reduction, the majority was independent of weight. A greater understanding of the pleotropic effects of GLP-1 RA that contribute to reduction in blood pressure could support developing future approaches for treating hypertension. Trial registrations (clinicaltrials.gov) NCT01064687, NCT00734474, NCT01769378, NCT02597049, NCT01149421, NCT03495102.

Glucagon-Like Peptide 1 Receptor Agonists Versus Sodium-Glucose Cotransporter 2 Inhibitors for Atherosclerotic Cardiovascular Disease in Patients With Type 2 Diabetes

Beyond improving hemoglobin A1c (HbA1c) in adults with type 2 diabetes, glucagon-like peptide 1 receptor agonists (GLP-1RA) have been approved for reducing risk of major adverse cardiovascular events (MACE) with established cardiovascular disease (CVD) or multiple CV risk factors. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) also reduced the risk for the primary composite CV outcome in patients with type 2 diabetes at high risk for CV events. In the American Diabetes Association (ADA) and European Association of Study in Diabetes (EASD) consensus report 2022, there is the description "In people with established atherosclerotic CVD (ASCVD) or with a high risk for ASCVD, GLP-1RA were prioritized over SGLT2i"; however, the evidence supporting such statement is limited. Therefore, we studied the superiority of GLP-1RA over SGLT2i for prevention of ASCVD from various viewpoints. We could not find a meaningful difference in the risk reduction in three-point MACE (3P-MACE), mortality due to any cause, mortality due to CV cause and nonfatal myocardial infarction between GLP-1RA and SGLT2i trials. The risk of nonfatal stroke decreased in all five GLP-1RA trials; however, two of three SGLT2i trials showed an increase in risk of nonfatal stroke. The risk of hospitalization for heart failure (HHF) decreased in all three SGLT2i trials, and one GLP-1RA trial showed an increase in risk of HHF. The risk reduction of HHF in SGLT2i trials was greater than that in GLP-1RA trials. These findings were consistent with current systematic reviews and meta-analyses. The risk reduction of 3P-MACE was significantly and negatively correlated with changes in HbA1c (R = -0.861, P = 0.006) and body weight (R = -0.895, P = 0.003) in GLP-1RA and SGLT2i trials. The studies using SGLT2i failed to reduce carotid intima media thickness (cIMT), the surrogate marker for atherosclerosis; however, several studies using GLP-1RA successfully reduced cIMT in patients with type 2 diabetes. Compared with SGLT2i, GLP-1RA had a higher probability of decreasing serum triglyceride. GLP-1RA have multiple vascular biological anti-atherogenic properties.

Effect of the Glucagon-Like Peptide-1 Receptor Agonists on Autonomic Function in Subjects with Diabetes: A Systematic Review and Meta-Analysis

BACKGROUND

In addition to the metabolic effects in diabetes, glucagon-like peptide 1 receptor (GLP-1R) agonists lead to a small but substantial increase in heart rate (HR). However, the GLP-1R actions on the autonomic nervous system (ANS) in diabetes remain debated. Therefore, this meta-analysis evaluates the effect of GLP-1R agonist on measures of ANS function in diabetes.

METHODS

According to the Cochrane Collaboration and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, we conducted a meta-analysis considering clinical trials in which the autonomic function was evaluated in diabetic subjects chronically treated with GLP-1R agonists. The outcomes were the change of ANS function measured by heart rate variability (HRV) and cardiac autonomic reflex tests (CARTs).

RESULTS

In the studies enrolled, HR significantly increased after treatment (P<0.001), whereas low frequency/high frequency ratio did not differ (P=0.410); no changes in other measures of HRV were detected. Considering CARTs, only the 30:15 value derived from lying-to-standing test was significantly lower after treatment (P=0.002), but only two studies reported this measurement. No differences in other CARTs outcome were observed.

CONCLUSION

The meta-analysis confirms the HR increase but seems to exclude an alteration of the sympatho-vagal balance due to chronic treatment with GLP-1R agonists in diabetes, considering the available measures of ANS function.

Nephroprotective Properties of the Glucose-Dependent Insulinotropic Polypeptide (GIP) and Glucagon-like Peptide-1 (GLP-1) Receptor Agonists

Diabetes mellitus is the leading cause of chronic kidney disease, and about 30–40% of patients with diabetes will develop kidney disease. Incretin hormones have received attention during the past three decades not only as a pharmacotherapy for the treatment of type 2 diabetes, but also for their cardiorenometabolic effects. The main incretins are glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Additional to the pancreas, receptors for GLP-1 are widely distributed in various organs, causing positive effects on endothelial function and vascular atherogenesis. Along with glycemic control and weight reduction, GLP-1 receptor agonists also strongly improve cardiovascular and renal outcomes in patients with type 2 diabetes. Recently, a dual GIP and GLP-1 receptor agonist has been approved for the treatment of type 2 diabetes. Compared to GLP-1 receptor agonist semaglutide, dual GIP and GLP-1 receptor agonist tirzepatide showed a superior reduction in hemoglobin A1c and body weight. Preliminary results also suggest that tirzepatide improves kidney outcomes in adults with type 2 diabetes with increased cardiovascular risk. In this review, we present the nephroprotective properties of dual GIP and GLP-1 receptor agonists as a new drug to treat type 2 diabetes.

Obesity-related vascular dysfunction persists after weight loss and is associated with decreased vascular glucagon-like peptide (GLP-1) 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. While 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 vasculo-protective properties, is decreased in plasma from obese patients. We hypothesize that obesity causes persistent vascular dysfunction in association with downregulation of vascular GLP-1R. Female Wistar rats were randomized into three groups: lean received a chow diet for 28 weeks, obese received a Western diet for 28 weeks, and reverse obese received a Western diet for 18 weeks followed by 12 weeks of standard chow diet. The obese group exhibited increased body weight and body mass index, while 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.

NAFLD in the Elderly

Non-alcoholic fatty liver disease (NAFLD) is an increasingly prevalent disease globally. Current estimates are that 24% of the adult population, thus, one billion individuals worldwide, are affected. Interestingly, the prevalence of fatty liver seems to peak between 40─50 years of age in males and 60─69 years in females, often slightly decreasing in older (>70 years) cohorts. Furthermore, several risk factors for NAFLD development, such as hypertension, diabetes, hyperlipidemia, and obesity are higher in older adults. The diagnosis and management strategies in older adults are sometimes challenging, and certain age-specific factors have to be taken into account by healthcare professionals. In this review, we provide an overview of considerations relevant to the management and diagnosis of NAFLD in older adults (age >65 years) and discuss the types of pharmacological interventions available for the management of non-alcoholic steatohepatitis (NASH) in the aging population.

Making a case for the combined use of SGLT2 inhibitors and GLP1 receptor agonists for cardiorenal protection

Sodium glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RA) were initially approved to improve glycemic control in the treatment of type 2 diabetes. Clinical trials have also demonstrated beneficial effects with regards to cardiovascular and renal parameters. Beyond improving glycemic control, these therapies promote weight loss and lower blood pressure when used individually, and in an additive manner when used together. Accordingly, taking advantage of complementary mechanisms of action with the combined use of these two classes of agents to further improve cardiorenal outcomes is conceptually appealing, but has yet to be explored in detail in clinical trials. In this review, we discuss proposed mechanisms for renal protection, clinical benefits, and adverse events associated with the individual and combined use of SGLT2 inhibitors and GLP-1RA. The management of type 2 diabetes has significantly changed over the last few years, moving away from solely glycemic control towards the concurrent management of associated comorbidities in a patient population at significant risk of cardiovascular disease and progression of chronic kidney disease. It is from this perspective that we seek to outline the rationale for the sequential and/or combined use of SGLT2 inhibitors and GLP-1RA in patients with type 2 diabetes.

A review of GLP-1 receptor agonists in type 2 diabetes: A focus on the mechanism of action of once-weekly agents

What is known and objective

Glucagon‐like peptide‐1 receptor agonists (GLP‐1 RAs) are one of the preferred approved treatment options for people with type 2 diabetes (T2D) and inadequate glycaemic control. The objective of this review is to provide a general clinical overview of the similarities and differences in the mechanisms of action (MoA) of the once‐weekly GLP‐1 RA class of medications, highlighting the role of pharmacists in providing optimal medication management, education and care for people with diabetes.

Methods

This is a narrative review of the published literature regarding the MoA of the currently available once‐weekly GLP‐1 RAs in T2D.

Results and discussion

GLP‐1 RAs have an established efficacy and safety profile. Their benefits derive from their blood glucose‐lowering effects, which include pancreatic beta‐cell‐mediated glucose‐dependent insulin secretion and suppressed glucagon release, and their ability to slow gastric emptying and promote satiety. GLP‐1 RAs may also exert beneficial effects on multiple organ systems in which GLP‐1 receptors are present, including the cardiovascular and renal systems. Differences between individual GLP‐1 RAs with regard to their molecular size, structure and duration of action (short or longer acting) have led to differing pharmacodynamics and clinical effects such as degree of glycaemic control, weight loss abilities, cardiovascular effects and tolerability profiles.

What is new and conclusion

From the literature, this appears to be the first review of the evidence base supporting the MoA of once‐weekly GLP‐1 RAs in T2D aimed at pharmacists, with a particular emphasis on the expanding role of pharmacists in team‐based diabetes management. As a class, GLP‐1 RAs are an effective treatment option for people with T2D, shown to achieve multi‐factorial clinical benefits. The results suggest that when selecting or advising about treatments, pharmacists should consider how the different once‐weekly GLP‐1 RAs and their MoA affect clinical outcomes in order to ensure optimal treatment for individuals.

Blood Pressure-Lowering Effect of Newer Antihyperglycemic Agents (SGLT-2 Inhibitors, GLP-1 Receptor Agonists, and DPP-4 Inhibitors)

The prevalence of arterial hypertension is high in patients with diabetes mellitus (DM). When DM and hypertension coexist, they constitute a dual cardiovascular threat and should be adequately controlled. Novel antihyperglycemic agents, including sodium-glucose co-transporter 2 (SGLT-2) inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1 RAs), and dipeptidyl peptidase-4 (DPP-4) inhibitors, have recently been used in the treatment of DM. Beyond their glucose-lowering effects, these drugs have shown beneficial pleiotropic cardiovascular effects, including lowering of arterial blood pressure (BP), as acknowledged in the 2019 European Society of Cardiology/European Association for the Study of Diabetes guidelines on diabetes, prediabetes, and cardiovascular diseases. The purpose of this review was to summarize the available information on the BP-reducing effects of these new glucose-lowering drug classes and provide a brief report on underlying pathophysiological mechanisms. We also compare the three drug classes (SGLT-2 inhibitors, GLP-1 RAs, and DPP-4 inhibitors) in terms of their BP-lowering effect and show that the greater BP reduction seems to be achieved with SGLT-2 inhibitors, whereas DPP-4 inhibitors have probably the mildest antihypertensive effect.

Cardiovascular Safety and Benefits of Noninsulin Antihyperglycemic Drugs for the Treatment of Type 2 Diabetes Mellitus-Part 1

Cardiovascular disease (CVD) is a major contributor to the morbidity and mortality associated with type 2 diabetes mellitus (T2DM). With T2DM growing in pandemic proportions, there will be profound healthcare implications of CVD in person with diabetes. The ideal drugs to improve outcomes in T2DM are those having antiglycemic efficacy in addition to cardiovascular (CV) safety, which has to be determined in appropriately designed CV outcome trials as mandated by regulatory agencies. Available evidence is largely supportive of metformin's CV safety and potential CVD risk reduction effects, whereas sulfonylureas are either CV risk neutral or are associated with variable CVD risk. Pioglitazone was also associated with improved CVD risk in patients with diabetes. The more recent antihyperglycemic medications have shown promise with regards to CVD risk reduction in T2DM patients at a high CV risk. Glucagon-like peptide-1 receptor agonists, a type of incretin-based therapy, were associated with better CV outcomes and mortality in T2DM patients, leading to the Food and Drug Administration approval of liraglutide to reduce CVD risk in high-risk T2DM patients. Ongoing and planned randomized controlled trials of the newer drugs should clarify the possibility of class effects, and of CVD risk reduction benefits in low-moderate CV risk patients. While metformin remains the first-line antiglycemic therapy in T2DM, glucagon-like peptide-1 receptor agonists should be appropriately prescribed in T2DM patients with baseline CVD or in those at a high CVD risk to improve CV outcomes. Dipeptidyl peptidase-4 inhibitors and sodium-glucose cotransporter-2 inhibitors are discussed in the second part of this review.

GLP-1 Receptor Agonists and SGLT2 Inhibitors for the Treatment of Type 2 Diabetes: New Insights and Opportunities for Cardiovascular Protection

The risk of cardiovascular disease (CVD) (myocardial infarction, stroke, peripheral vascular disease) is twice in type 2 diabetes (T2D) patients compared to non-diabetic subjects. Furthermore, cardiovascular disease (CV) is the leading cause of death in patients with T2D.In the last years several clinical intervention studies with new anti-hyperglycaemic drugs have been published, and they have shown a positive effect on the reduction of mortality and cardiovascular risk in T2D patients. In particular, these studies evaluated sodium/glucose-2 cotransporter inhibitors (SGLT2i) and Glucagon-like peptide-1 receptor agonists (GLP-1RA).In secondary prevention, it was clearly demonstrated that SGLT2i and GLP-1RA drugs reduce CV events and mortality, and new guidelines consider now these drugs as first choice (after metformin) in the treatment of T2D; there are also some signs that they may be effective also in primary prevention of CVD. However, the mechanisms involved in cardiovascular protection are not yet fully understood, but they appear to be both "glycaemic" and "extra-glycaemic".In this review, we will examine the fundamental results of the clinical trials on SGLT2i and GLP-1RA, their clinical relevance in term of treatment of T2D, and we will discuss the mechanisms that may explain how these drugs exert their cardiovascular protective effects.

Effects of liraglutide on diastolic function parameters in patients with type 2 diabetes and coronary artery disease: a randomized crossover study

Background

Diastolic dysfunction is highly prevalent in patients with type 2 diabetes mellitus (T2DM) and is associated with overweight, glucose dysregulation and coronary artery disease (CAD). The GLP-1 receptor agonist, liraglutide, has shown to induce weight loss and improve metabolic factors, thus modulating factors associated with diastolic dysfunction. We have previously reported the effects of liraglutide on systolic function, and in this current study we explore the effects of liraglutide on diastolic function parameters in patients with stable CAD, preserved left ventricular ejection fraction (LVEF), and newly diagnosed T2DM.

Methods

Thirty subjects were randomized to liraglutide or placebo intervention for 12 + 12-weeks in this double-blind cross-over study. 2D-echocardiography using tissue velocity imaging was used for assessment of diastolic function parameters. Early diastolic filling velocity (E), late atrial filling velocity (A), E-wave deceleration time (EDT) and E/A ratio was assessed from the pulse wave (PW)-Doppler velocity recording of the mitral inflow. Peak early diastolic annular velocities (e′) was measured from color tissue doppler images.

Results

Liraglutide, when compared to placebo, induced a significant reduction in average e′ and lateral e′ velocities (– 0.57 cm/s [– 1.05 to − 0.08] and –0.74 cm/s [–1.32 to –0.15], respectively). Adjusted for the concomitant increase in HR (+ 6.16 bpm [0.79 to 11.54], the changes were not significant. No significant changes in other diastolic function parameters were observed.

Conclusions

Liraglutide therapy did not improve any diastolic function parameters in subjects with T2DM, CAD, and preserved LVEF. Instead, a deterioration in e’ was observed, which was associated to an increase in heart rate induced by liraglutide therapy.

Trial registration Clinical Trial Registration: http://www.clinicaltrials.gov (unique identifier: NCT01595789) (first submitted May 8, 2012)

New hypoglycaemic therapy in frail older people with diabetes mellitus-phenotypic status likely to be more important than functional status

Frail older people are largely excluded from clinical trials and therefore glycaemic targets and optimum hypoglycaemic therapy in this group has not been fully investigated. Guidelines generally recommend tight glycaemic control in functionally fit individuals and relaxed targets in frail ones mainly due to the fear of hypoglycaemia. The newly introduced sodium glucose cotransporter-2 inhibitors and the glucagon like peptide-1 receptor agonists have shown benefit that is independent of glycaemic control and a minimal risk of hypoglycaemia. However, guidelines still express caution about its use in frail older people due to fear of other side effects such as weight loss, hypotension and falls. Some frail older people will miss out on the benefits of this new therapy if frailty is considered as a one entity with a blanket application of guidelines. We propose that frailty should be viewed as two distinct metabolically different phenotypes, the sarcopenic-obese, in which new therapy will improve their metabolic profile and should be liberally used if no contraindications, and the anorexic-malnourished phenotype in which the new therapy should be cautiously considered. In other words, glycaemic targets should be driven by individual's overall function but the use of new therapy should be driven by frailty phenotype.

Semaglutide for the treatment of non-alcoholic steatohepatitis: Trial design and comparison of non-invasive biomarkers

Non-alcoholic steatohepatitis (NASH) is a chronic liver disease. There is a clear need to develop pharmacological treatment for patients with NASH as well as biomarkers that can diagnose the disease. We describe a trial of semaglutide treatment for NASH, identify key patient characteristics and compare the relationship of patient characteristics and non-invasive biomarkers/scores. NCT02970942 is a randomised, double-blind, placebo-controlled, multi-national Phase 2 trial of daily subcutaneous semaglutide (0.1 mg, 0.2 mg, 0.4 mg) in patients with biopsy-confirmed NASH, F1-F3 fibrosis, NAFLD Activity Score ≥ 4, and body mass index (BMI) > 25 kg/m². Exploratory analyses were performed to evaluate correlations between baseline parameters and biomarkers in NASH. Mean (standard deviation [SD]) age of 320 randomised patients was 55 (11) years, mean BMI was 36 (6) kg/m², and 199 (62%) had type 2 diabetes. Of the total patients, 28% had F1 fibrosis, 23% had F2 fibrosis and 49% had F3 fibrosis. The highest area under the receiver operating characteristic curve (0.69) for accuracy in classifying fibrosis stage, F2-3 versus F1, was observed for Fib-4 and Enhanced Liver Fibrosis (ELF). No substantial correlation between BMI or other clinical or biochemical parameters and fibrosis stage was observed. In this large Phase 2 trial of semaglutide treatment for NASH, the clinical profile of enrolled patients was typical for patients with NASH. Of the investigated biomarkers/scores, ELF and Fib-4 showed the most apparent correlation in classifying fibrosis stage, but had only moderate predictive value.

Antidiabetic drugs and blood pressure changes

New era antidiabetic drugs are characterized by cardiovascular safety, including specific outcome benefits observed in randomized clinical trials (RCTs). It has been postulated that the favorable effects of new antidiabetic agents are related both to better control of blood pressure (BP) levels and to activation of multiple anti-atherosclerotic properties. In this review, we aimed to assess whether antidiabetic drugs have a pressor effect in glucose control and outcome-oriented RCTs, and to summarize the activated pathophysiological mechanisms relevant to BP control following the use of different antidiabetic drug classes. We also tried to determine which, if any, are the BP-lowering effects of more intense vs less intense glucose-lowering strategy irrespectively of trial antidiabetic regimen. To provide more robust results and evidence-based argumentation, a meta-analysis of placebo-controlled antidiabetic drug RCTs was undertaken to estimate the ongoing BP reduction for all considered and each separate drug class alone. This quantitative synthesis might be helpful for the clinician 1) to select or avoid the use of some classes of antidiabetic agents with a potential favorable or adverse pressor effect, respectively 2) to organize the overall drug regimen in patients with diabetes mellitus and minimize side effects because of concomitant use of drugs with established pressor effect (i.e. antihypertensive agents). This review was also organized to indicate whether BP change associated with different antidiabetic treatments may explain the specific macrovascular outcome benefits. Between all antidiabetic drugs including exogenous insulin, only sodium-glucose cotransporter 2 inhibitors produce a clinically important BP-lowering effect, but this BP reduction alone cannot explain the observed cardiovascular benefit.

The treament of hyperglycemia in acute ischemic stroke with incretin-based drugs

Stroke is a major cause of mortality and morbidity worldwide. Considerable experimental and clinical evidence suggests that both diabetes mellitus (DM) and post-stroke hyperglycemia are associated with increased mortality rate and worsened clinical conditions in acute ischemic stroke (AIS) patients. Insulin treatment does not seem to provide convincing benefits for these patients, therefore prompting a change of strategy. The selective agonists of Glucagon-Like Peptide-1 Receptors (GLP-1Ras) and the Inhibitors of Dipeptidyl Peptidase-IV (DPP-IVIs, gliptins) are two newer classes of glucose-lowering drugs used for the treatment of DM. This review examines in detail the rationale for their development and the physicochemical, pharmacokinetic and pharmacodynamic properties and clinical activities. Emphasis will be placed on their neuroprotective effects at cellular and molecular levels in experimental models of acute cerebral ischemia. In perspective, an adequate basis does exist for a novel therapeutic approach to hyperglycemia in AIS patients through the additive treatment with GLP-1Ras plus DPP-IVIs.

GLP-1 Receptor Agonists and Diabetic Kidney Disease: A Call of Attention to Nephrologists

Type 2 diabetes mellitus (T2DM) represents the main cause of chronic kidney disease (CKD) and end-stage renal disease (ESKD), and diabetic kidney disease (DKD) is a major cause of morbidity and mortality in diabetes. Despite advances in the nephroprotective treatment of T2DM, DKD remains the most common complication, driving the need for renal replacement therapies (RRT) worldwide, and its incidence is increasing. Until recently, prevention of DKD progression was based around strict blood pressure (BP) control, using renin-angiotensin system blockers that simultaneously reduce BP and proteinuria, adequate glycemic control and control of cardiovascular risk factors. Glucagon-like peptide-1 receptor agonists (GLP-1RA) are a new class of anti-hyperglycemic drugs shown to improve cardiovascular and renal events in DKD. In this regard, GLP-1RA offer the potential for adequate glycemic control in multiple stages of DKD without an increased risk of hypoglycemia, preventing the onset of macroalbuminuria and slowing the decline of glomerular filtration rate (GFR) in diabetic patients, also bringing additional benefit in weight reduction, cardiovascular and other kidney outcomes. Results from ongoing trials are pending to assess the impact of GLP-1RA treatments on primary kidney endpoints in DKD.

Effect of Hemoglobin A1c Reduction or Weight Reduction on Blood Pressure in Glucagon-Like Peptide-1 Receptor Agonist and Sodium-Glucose Cotransporter-2 Inhibitor Treatment in Type 2 Diabetes Mellitus: A Meta-Analysis

Background Glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2is) have shown their beneficial effects on cardiovascular outcomes and multiple cardiovascular risk factors, including hypertension. However, the mechanism of blood pressure (BP)-lowering effects of these agents has not been elucidated. This study aims to evaluate the effect of hemoglobin A1c reduction or body weight reduction with GLP-1RA treatment and SGLT2i treatment on BP changes in patients with type 2 diabetes mellitus. Methods and Results Studies were identified by a search of MEDLINE, EMBASE, and the Cochrane Central Register until June 2019. Meta-regression analysis was performed to evaluate the association between hemoglobin A1c reduction or body weight reduction and changes of BP. A total of 184 trials were included. Both GLP-1RA and SGLT2i led to significant reductions in systolic BP (weighted mean difference, -2.856 and -4.331 mm Hg, respectively; P<0.001 for both) and diastolic BP (weighted mean difference, -0.898 and -2.279 mm Hg, respectively; P<0.001 for both). For both drug classes, hemoglobin A1c reduction was not independently associated with systolic BP reduction or diastolic BP reduction. In GLP-1RA treatment, weight reduction was positively associated with systolic BP reduction and diastolic BP reduction (β=0.821 and β=0.287, respectively; P<0.001 for both). In SGLT2i treatment, weight loss was significantly associated with systolic BP reduction (β=0.820; P=0.001) but was not associated with diastolic BP reduction. Conclusions Treatment with GLP-1RA and SGLT2i led to significant reductions in BP in patients with type 2 diabetes mellitus. Weight reduction was significantly and independently associated with BP reductions in GLP-1RA treatment and SGLT2i treatment.

Conceptualization of a Parasympathetic Endocrine System

We here propose a parasympathetic endocrine system (PES) comprised of circulating peptides released from secretory cells in the gut, significantly modulated by vagal projections from the dorsal motor nucleus of the vagus (DMV). While most of these gut peptides mediate well-described satiety and digestive effects that increase parasympathetic control of digestion (Lee et al., 1994; Gutzwiller et al., 1999; Klok et al., 2007), they also have actions that are far-reaching and increase parasympathetic signaling broadly throughout the body. The actions beyond satiety that peptides like somatostatin, cholecystokinin, glucagon-like peptide 1, and vasoactive intestinal peptide have been well-examined, but not in a systematic way. Consideration has been given to the idea that these and other gut-derived peptides are part of an endocrine system has been partially considered (Rehfeld, 2012; Drucker, 2016), but that it is coordinated through parasympathetic control and may act to increase the actions of parasympathetic projections has not been formalized before. Here only gut-derived hormones are included although there are potentially other parasympathetically mediated factors released from other sites like lung and liver (Drucker, 2016). The case for the existence of the PES with the DMV as its integrative controller will be made through examination of an anatomical substrate and evidence of physiological control mechanisms as well as direct examples of PES antagonism of sympathetic signaling in mammals, including humans. The implications for this conceptual understanding of a PES reframe diseases like metabolic syndrome and may help underscore the role of the autonomic nervous system in the associated symptoms.

Development of therapeutic options on type 2 diabetes in years: Glucagon-like peptide-1 receptor agonist’s role intreatment; from the past to future

Diabetes mellitus (DM) is a chronic metabolic disease characterized by hypergly-cemia. Type 2 diabetes (T2DM) accounting for 90% of cases globally. The worldwide prevalence of DM is rising dramatically over the last decades, from 30 million cases in 1985 to 382 million cases in 2013. It’s estimated that 451 million people had diabetes in 2017. As the pathophysiology was understood over the years, treatment options for diabetes increased. Incretin-based therapy is one of them. Glucagon-like peptide-1 receptor agonist (GLP-1 RA) not only significantly lower glucose level with minimal risk of hypoglycemia but also, they have an important advantage in themanagement of cardiovascular risk and obesity. Thus, we will review here GLP-1 RAsrole in the treatment of diabetes.

Effects of glucagon-like peptide 1 receptor agonists on comorbidities in older patients with diabetes mellitus

Elderly patients with diabetes are at high risk of polypharmacy because of multiple coexisting diseases and syndromes. Polypharmacy increases the risk of drug–drug and drug–disease interactions in these patients, who may already have age-related sensory and cognitive deficits; such deficits may delay timely communication of early symptoms of adverse drug events. Several glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have been approved for diabetes: liraglutide, exenatide, lixisenatide, dulagluatide, semaglutide, and albiglutide. Some are also approved for treatment of obesity. The current review of literature along with clinical case discussion provides evidence supporting GLP-1 RAs as diabetes medications for polypharmacy reduction in older diabetes patients because of their multiple pleiotropic effects on comorbidities (e.g. hyperlipidemia, hypertension, and fatty liver) and syndromes (e.g. osteoporosis and sleep apnea) that commonly co-occur with diabetes. Using one medication (in this case, GLP-1 RAs) to address multiple conditions may help reduce costs, medication burden, adverse drug events, and medication nonadherence.

Effect of semaglutide on liver enzymes and markers of inflammation in subjects with type 2 diabetes and/or obesity

BACKGROUND

Obesity and type 2 diabetes are drivers of non-alcoholic fatty liver disease (NAFLD). Glucagon-like peptide-1 analogues effectively treat obesity and type 2 diabetes and may offer potential for NAFLD treatment.

AIM

To evaluate the effect of the glucagon-like peptide-1 analogue, semaglutide, on alanine aminotransferase (ALT) and high-sensitivity C-reactive protein (hsCRP) in subjects at risk of NAFLD.

METHODS

Data from a 104-week cardiovascular outcomes trial in type 2 diabetes (semaglutide 0.5 or 1.0 mg/week) and a 52-week weight management trial (semaglutide 0.05-0.4 mg/day) were analysed. Treatment ratios vs placebo were estimated for ALT (both trials) and hsCRP (weight management trial only) using a mixed model for repeated measurements, with or without adjustment for change in body weight.

RESULTS

Elevated baseline ALT (men >30 IU/L; women >19 IU/L) was present in 52% (499/957) of weight management trial subjects. In this group with elevated ALT, end-of-treatment ALT reductions were 6%-21% (P<0.05 for doses≥0.2 mg/day) and hsCRP reductions 25%-43% vs placebo (P < 0.05 for 0.2 and 0.4 mg/day). Normalisation of elevated baseline ALT occurred in 25%-46% of weight management trial subjects, vs 18% on placebo. Elevated baseline ALT was present in 41% (1325/3268) of cardiovascular outcomes trial subjects. In this group with elevated ALT, no significant ALT reduction was noted at end-of-treatment for 0.5 mg/week, while a 9% reduction vs placebo was seen for 1.0 mg/week (P = 0.0024). Treatment ratios for changes in ALT and hsCRP were not statistically significant after adjustment for weight change.

CONCLUSIONS

Semaglutide significantly reduced ALT and hsCRP in clinical trials in subjects with obesity and/or type 2 diabetes.

Novel pharmacological therapy in type 2 diabetes mellitus with established cardiovascular disease: Current evidence

Cardiovascular diseases (CVDs) remain the leading cause of death in the world and in most developed countries. Patients with type 2 diabetes mellitus (T2DM) suffer from both microvascular and macrovascular diseases and therefore have higher rates of morbidity and mortality compared to those without T2DM. If current trends continue, the Center for Disease Control and Prevention estimates that 1 in 3 Americans will have T2DM by year 2050. As a consequence of the controversy surrounding rosiglitazone and the increasing prevalence of diabetes and CVDs, in 2008 the Food and Drug Administration (FDA) established new expectations for the evaluation of new antidiabetic agents, advising for pre and, in some cases, post-marketing data on major cardiovascular events. As a direct consequence, there has been a paradigm shift in new antidiabetic agents that has given birth to the recently published American Diabetes Association/European Association for the Study of Diabetes consensus statement recommending sodium-glucose cotransporter-2 inhibitors (SGLT2i) and glucagon like peptide-1 receptor agonists (GLP-1RA) in patients with T2DM and established CVD. As a result of over a decade of randomized placebo controlled cardiovascular outcome trials, the aforementioned drugs have received FDA approval for risk reduction of cardiovascular (CV) events in patients with T2DM and established CV disease. SGLT2i have been shown to have a stronger benefit in patients with congestive heart failure and diabetic kidney disease when compared to their GLP-1RA counterparts. These benefits are not withstanding additional considerations such as cost and the multiple FDA Black Box warnings. This topic is currently an emerging research area and this mini-review paper examines the role of these two novel classes of drugs in patients with T2DM with both confirmed, and at risk for, CVD.

DPP-4 Inhibitors as Potential Candidates for Antihypertensive Therapy: Improving Vascular Inflammation and Assisting the Action of Traditional Antihypertensive Drugs

Dipeptidyl peptidase-4 (DPP-4) is an important protease that is widely expressed on the surface of human cells and plays a key role in immune-regulation, inflammation, oxidative stress, cell adhesion, and apoptosis by targeting different substrates. DPP-4 inhibitors (DPP-4i) are commonly used as hypoglycemic agents. However, in addition to their hypoglycemic effect, DPP-4i have also shown potent activities in the cardiovascular system, particularly in the regulation of blood pressure (BP). Previous studies have shown that the regulatory actions of DPP-4i in controlling BP are complex and that the mechanisms involved include the functional activities of the nerves, kidneys, hormones, blood vessels, and insulin. Recent work has also shown that inflammation is closely associated with the elevation of BP, and that the inhibition of DPP-4 can reduce BP by regulating the function of the immune system, by reducing inflammatory reactions and by improving oxidative stress. In this review, we describe the potential anti-hypertensive effects of DPP-4i and discuss potential new anti-hypertensive therapies. Our analysis indicated that DPP-4i treatment has a mild anti-hypertensive effect as a monotherapy and causes a significant reduction in BP when used in combined treatments. However, the combination of DPP-4i with high-dose angiotensin converting enzyme inhibitors (ACEI) can lead to increased BP. We suggest that DPP-4i improves vascular endothelial function in hypertensive patients by suppressing inflammatory responses and by alleviating oxidative stress. In addition, DPP-4i can also regulate BP by activating the sympathetic nervous system, interfering with the renin angiotensin aldosterone system (RAAS), regulating Na/H₂O metabolism, and attenuating insulin resistance (IR).

Hypertension in Obesity: Novel Insights

BACKGROUND

The relationship between obesity and hypertension has been established in both adults and children. The combination of obesity, hypertension and other cardiovascular risk factors significantly increases the likelihood of adverse cardiovascular effects and raises concerns about aggressive treatment strategies.

OBJECTIVE

Despite the impressive elements which indicate an important role for excessive weight gain in increasing blood pressure, not all obese patients are hypertensive. A subgroup of obese people may not develop hypertension. Furthermore, masked hypertension occurs more common among obese patients, and body fat distribution has a major role in the development of hypertension.

METHOD

We conducted a research of the relevant literature regarding obesity-induced hypertension and possible treatment strategies.

RESULTS

Successful weight loss is correlated with blood pressure reduction and requires a multidisciplinary approach that includes personalized dietary interventions combined with regular exercise and cognitive behavioral therapy.

CONCLUSION

Pharmacological therapy may be considered as part of a comprehensive obesity management strategy. More research and new treatment therapies are required in this field.

Effect of liraglutide on ambulatory blood pressure in patients with hypertension and type 2 diabetes: A randomized, double-blind, placebo-controlled trial

AIMS

To assess the effect of liraglutide on 24-hour ambulatory blood pressure and heart rate in patients with hypertension (pre- and stage 1 hypertension) and inadequately controlled Type 2 diabetes (glycated haemoglobin 7%-10% [53-86 mmol/mol]).

MATERIALS AND METHODS

Eligible patients for this investigator-initiated, parallel-group, randomized, double-blind trial were on stable background antihyperglycaemic therapy excluding insulin, glucagon-like peptide-1 receptor agonists and dipeptidyl-peptidase-4 inhibitors. Participants were centrally randomized in a 1:1 ratio to daily liraglutide 0.6 mg, titrated to 1.2 mg after the first week, or placebo for 5 weeks. The primary outcome was change in 24-hour ambulatory systolic blood pressure (SBP), and secondary outcomes included change in ambulatory diastolic blood pressure (DBP) and heart rate. We also assessed renal sodium handling.

RESULTS

Of 87 patients assessed for eligibility, 62 (66.1% men) with a mean age of 60.2 years were randomized to liraglutide (n = 31) or placebo (n = 31). All participants received background therapy with metformin, whilst 35.5% were treated concomitantly with sulphonylureas and 14.5% with pioglitazone. Compared with placebo, liraglutide reduced 24-hour SBP by -5.73 mm Hg (95% confidence interval [CI] -9.81 to -1.65) and had a neutral effect on 24-hour DBP (mean difference - 1.42 mm Hg; 95% CI -4.25 to 1.40), whilst increasing 24-hour heart rate by 6.16 beats/min (95% CI 3.25 to 9.07). Findings were consistent for daytime and night-time measurements. Liraglutide did not increase urine sodium excretion.

CONCLUSION

Based on 24-hour ambulatory measurements, short-term treatment with liraglutide had a favourable effect on SBP whilst increasing heart rate.

Exenatide once-weekly improves metabolic parameters, endothelial dysfunction and carotid intima-media thickness in patients with type-2 diabetes: An 8-month prospective study

AIM

To evaluate the effect of exenatide long acting release (LAR) on carotid intima-media thickness (IMT) and endothelial function in patients with type 2 diabetes mellitus.

METHODS

Sixty subjects with type 2 diabetes mellitus were treated with exenatide LAR as add-on to stable doses of metformin for 8 months in an open label study. Anthropometric variables, lipid profile and glycemic parameters were assessed by routine analysis. Carotid IMT by Doppler ultrasound and endothelial function by flow-mediated dilation of the brachial artery were also assessed.

RESULTS

Exenatide significantly improved fasting glycaemia (from 8.8 ± 2.8 to 7.3 ± 2.2 mmol/L, p < 0.0001), HbA1c (from 8.0 ± 0.4 to 6.9 ± 1.1%, p < 0.0001), body mass index (from 33 ± 9 to 31 ± 6 kg/m², p = 0.0348) and waist circumference (from 109 ± 13 to 106 ± 13 cm, p = 0.0105). There was a significant improvement of the lipid profile, except in triglyceride level where no changes were observed. Carotid IMT and flow-mediated dilation were also improved (from 0.98 ± 0.14 to 0.87 ± 0.15 mm and from 5.8 ± 1.3 to 6.8 ± 1.7%, respectively; p < 0.0001 for both).

CONCLUSIONS

Treatment with exenatide LAR led to improved cardio-metabolic parameters, including carotid IMT and flow-mediated dilation, independently of glucometabolic control. These results may help to explain, at least in part, the cardiovascular safety of exenatide LAR, as recently reported in cardiovascular outcome trials.

A Prospective Single-Arm Trial of Modified Long Biliopancreatic and Short Alimentary Limbs Roux-En-Y Gastric Bypass in Type 2 Diabetes Patients with Mild Obesity

BACKGROUND

Type-2 diabetes (T2D) patients with body mass index (BMI) below 35 kg/m² carry lower remission rates than severely obese T2D individuals submitted to "standard limb lengths" Roux-en-Y gastric bypass (RYGB). Mild-obese patients appear to have more severe forms of T2D, where the mechanisms of glycemic control after a standard-RYGB may be insufficient. The elongation of the biliopancreatic limb may lead to greater stimulation of the distal intestine, alterations in bile acids and intestinal microbiota, among other mechanisms, leading to better metabolic outcomes. The aim of this study is to evaluate the safety and efficacy of the RYGB with a biliopancreatic limb of 200 cm in the control of T2D in patients with BMI 30-35 kg/m².

METHODS

From January 2011 to May 2015, 102 T2D patients with BMI from 30 to 34.9 kg/m² underwent laparoscopic RYGB with the biliopancreatic-limb of 200 cm and the alimentary-limb of 50 cm.

RESULTS

There were no deaths or reoperations. The mean follow-up was 28.1 months. The mean BMI dropped from 32.5 to 25.1 kg/m², while the mean fasting glucose decreased from 182.9 to 89.8 mg/dl and the mean glycated hemoglobin (HbA1c) went from 8.7 to 5.2%. During follow-up, 92.2% had their T2D under complete control (HbA1c < 6%, no anti-diabetic medications), while 7.8% were under partial control. Control of hypertension and dyslipidemia were 89.4 and 85.5%, respectively. No patient developed hypoalbuminemia, and there were mild micronutrient deficiencies.

CONCLUSIONS

RYGB with long-biliopancreatic and short-alimentary limbs is safe and seems effective in achieving complete control of T2D in patients with BMIs between 30 and 35 kg/m².

The Ascending GLP-1 Road From Clinical Safety to Reduction of Cardiovascular Complications

Glucagon-like peptide 1 (GLP-1) was originally identified as a gut-derived incretin hormone that lowered glycemia through potentiation of glucose-dependent insulin secretion. Subsequent studies expanded the actions of GLP-1 to include inhibition of glucagon secretion, gastric emptying, and appetite, collectively useful attributes for a glucose-lowering agent. The introduction of GLP-1 receptor (GLP-1R) agonists for the treatment of diabetes was associated with questions surrounding their safety, principally with regard to medullary thyroid cancer, pancreatitis, and pancreatic cancer, yet cardiovascular outcome trials subsequently revealed reductions in rates of stroke, myocardial infarction, and cardiovascular death with a paucity of major safety signals. We discuss the controversies, unanswered questions, and established use of GLP-1R agonists from a mechanistic and clinical perspective. We highlight methods for detection and cellular sites of GLP-1R expression, key uncertainties, recent insights, and experimental caveats surrounding the use of GLP-1R agonists for the treatment of diabetes and the reduction of diabetes-related complications.

Liraglutide protects cardiac function in diabetic rats through the PPARα pathway

Increasing evidence shows that diabetes causes cardiac dysfunction. We hypothesized that a glucagon-like peptide-1 analogue, liraglutide, would attenuate cardiac dysfunction in diabetic rats. Twenty-four Sprague Dawley (SD) rats were divided into 2 groups fed either a normal diet (normal, n = 6) or a high-fat diet (HFD, n = 18) for 4 weeks. Then, the HFD rats were injected with streptozotocin (STZ) to create a diabetic rat model. Diabetic rats were divided into 3 subgroups receiving vehicle (diabetic, n = 6), a low dose of liraglutide (Llirag, 0.2 mg/kg/day, n = 6) or a high dose of liraglutide (Hlirag, 0.4 mg/kg/day, n = 6). Metabolic parameters, systolic blood pressure, heart rate, left ventricular (LV) function, and whole genome expression of the heart were determined. Diabetic rats developed insulin resistance, increased blood lipid levels and oxidative stress, and impaired LV function, serum adiponectin, NO. Liraglutide improved insulin resistance, serum adiponectin, NO, heart rate and LV function and reduced blood triglyceride, total cholesterol levels and oxidative stress. Moreover, liraglutide increased heart Nr1h3 , Ppar-α and Srebp expression and reduced Dgat , and Angptl3 expression. Liraglutide prevented in cardiac dysfunction by activating the PPARα pathway to inhibit Dgat expression and oxidative stress in diabetic rats.

Incretins: Beyond type 2 diabetes

While the use of incretins, including GLP-1 receptor agonists and PDD-IV inhibitors, is well established in the treatment of type 2 diabetes, many other aspects of these agents are yet to be discovered and utilized for their potential clinical benefit. These include the potential role of GLP-1 receptor agonists in the induction of weight loss, blood pressure reduction, anti-inflammatory and nephro- and cardio-protective actions. Their potential benefit in type 1 diabetes is also being investigated. This review will attempt to comprehensively describe novel discoveries in the field of incretin pathophysiology and pharmacology beyond their classical role in the treatment of type 2 diabetes.

A comparative safety review between GLP-1 receptor agonists and SGLT2 inhibitors for diabetes treatment

INTRODUCTION

Glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium glucose cotransporter 2 inhibitors (SGLT2i) are of particular interest in type 2 diabetes treatment strategies, due to their efficacy in reducing HbA1c with a low risk of hypoglycaemia, to their positive effects on body weight and blood pressure and in light of their effects on cardiovascular risk and on nephroprotection emerged from the most recent cardiovascular outcome trials. Since it is therefore very likely that GLP-1RA and SGLT2i use will become more and more common, it is more and more important to gather and discuss information about their safety profile.

AREAS COVERED

Adverse events and the safety concerns most often emerged in trials with GLP-1RA namely, exenatide long acting release (LAR), dulaglutide, liraglutide, semaglutide, lixisenatide or SGLT2i, namely empagliflozin, dapagliflozin, canagliflozin and SGLT2i with an attempt at comparing the safety profiles of molecules of these two classes.

EXPERT OPINION

GLP-1RA and SGLT2i, although each associated with different specific side effects, share a 'similar' safety profile and are both drugs relatively easy to handle. The potentially complementary mechanisms of action, the cardio and nephroprotective effects demonstrated by molecules of both classes, make these drugs potentially useful even in add on to each other.

Long-term effects of sitagliptin in patients with type 2 diabetes mellitus and hypertension: results from the PROLOGUE study

Background

The effects of sitagliptin in patients with type 2 diabetes mellitus and hypertension are unclear. Therefore, we evaluated the long-term effects of sitagliptin in those patients.

Methods

In the PROLOGUE study, 365 patients were diagnosed as type 2 diabetes mellitus and hypertension, and 189 patients in the sitagliptin group, 176 patients in the conventional group. Fasting blood glucose (FBG), HbA1c, systolic pressure (SP), diastolic pressure (DP), serum urea nitrogen (BUN) and serum creatinine (SCR) were measured at the beginning of the study and after 12 and 24 months of treatment.

Results

FBS and HbA1c levels were not significantly decreased after treatment [12 months: OR: -3.1, 95% CI (-11.3, 5.0); OR: 0.1, 95% CI (0.0, 0.3); 24 months: OR: -0.1, 95% CI (-9.1, 8.8); OR: 0.1, 95% CI (0.0, 0.3), respectively]. BP and DP levels were not significantly decreased after treatment (12 months: OR: 0.9, 95% CI (-2.8, 4.6); OR: 0.6, 95% CI (-2.0, 3.2); 24 months: OR: -0.5, 95% CI (-4.2, 3.1); OR: -1.6, 95% CI (-41, 0.9), respectively]. Furthermore, BUN and SCR levels were not significantly decreased after treatment (12 months: OR: 0.0, 95%CI (-1.2, 1.2); OR: 0.0, 95% CI (-0.1, 0.0); 24 months: OR: 0.4, 95% CI (-1.0, 1.8); OR: -80.8, 95% CI (-201.3, 39.8), respectively]. After adjusting for confounding factors, our results did not change.

Conclusions

In our study, there was no evidence that treatment with sitagliptin can improve FBS, BP, DP, BUN or SCR in patients with type 2 diabetes mellitus and hypertension.

Trial Registration

University Hospital Medical Information Network Clinical Trials Registry UMIN000004490.

Pharmacokinetic Properties of Liraglutide as Adjunct to Insulin in Subjects with Type 1 Diabetes Mellitus

Background

The pharmacokinetic properties of liraglutide, a glucagon-like peptide-1 receptor agonist approved for the treatment of type 2 diabetes mellitus (T2D), have been established in healthy individuals and subjects with T2D. Liraglutide has been under investigation as adjunct treatment to insulin in type 1 diabetes mellitus (T1D). This single-center, double-blind, placebo-controlled, crossover, clinical pharmacology trial is the first to analyze the pharmacokinetic properties of liraglutide as add-on to insulin in T1D.

Methods

Subjects (18–64 years; body mass index 20.0–28.0 kg/m²; glycated hemoglobin ≤9.5 %) were randomized 1:1:1 to 0.6, 1.2, or 1.8 mg liraglutide/placebo. Each group underwent two 4-week treatment periods (liraglutide then placebo or placebo then liraglutide) separated by a 2- to 3-week washout. Both trial drugs were administered subcutaneously, once daily, as adjunct to insulin. A stepwise hypoglycemic clamp was performed at the end of each treatment period (data reported previously). Pharmacokinetic endpoints were derived from liraglutide concentration–time curves after the final dose and exposure was compared with data from previous trials in healthy volunteers and subjects with T2D.

Results

The pharmacokinetic properties of liraglutide in T1D were comparable with those observed in healthy volunteers and subjects with T2D. Area under the steady-state concentration–time curve (AUC) and maximum plasma concentration data were consistent with dose proportionality of liraglutide. Comparison of dose-normalized liraglutide AUC suggested that exposure in T1D, when administered with insulin, is comparable with that observed in T2D.

Conclusions

Liraglutide, administered as adjunct to insulin in subjects with T1D, shows comparable pharmacokinetics to those in subjects with T2D.

ClinicalTrials.gov Identifier: NCT01536665.

Effects of the glucagon-like peptide-1 receptor agonist liraglutide on 24-h ambulatory blood pressure in patients with type 2 diabetes and stable coronary artery disease: a randomized, double-blind, placebo-controlled, crossover study

OBJECTIVE

The glucagon-like peptide-1 receptor agonist liraglutide has been shown to reduce blood pressure (BP) in clinical trials using office BP measurements. However, the effects of liraglutide on 24-h BP and on the diurnal variation in BP have not been explored sufficiently.

METHODS

Forty-one patients with type 2 diabetes and stable coronary artery disease were randomized to receive liraglutide or placebo to a backbone therapy of metformin in this double-blind, placebo-controlled 12 along with 12 weeks crossover study. Ambulatory blood pressure monitoring (ABPM) was performed at the start and end of each intervention.

RESULTS

Twenty-four individuals completed all 24-h BP measurements. Liraglutide, when compared with placebo, did not induce any significant changes in mean 24-h SBP [difference +1.8 mmHg (95% confidence interval, 95% CI: -4.33 to 7.93)] or DBP [+4.2 mmHg (-0.74 to 9.17)]. Twenty-four-hour BP profiles revealed a trend for increase in evening SBP and DBP [+9.2 mmHg (95% CI: 1.1-17.2) and +9.7 mmHg (95% CI: 3.9-15.5), respectively]. Mean heart rate significantly increased after liraglutide [+7.6 bpm (95% CI: 2.56-12.62)]. Liraglutide did not affect the BP variability or the nocturnal BP dipping.

CONCLUSIONS

We could not demonstrate any BP-lowering effect of liraglutide when using 24-h ABPM. Liraglutide exhibited diurnal variation in the effect on BP without affecting the BP variability or nocturnal BP dipping.

A Review of the Long-Term Efficacy, Tolerability, and Safety of Exenatide Once Weekly for Type 2 Diabetes

Introduction

Exenatide once weekly (ExeOW, Bydureon^®, Astra Zeneca), a drug belonging to the class of glucagon-like peptide-1 (GLP-1) receptor agonists, is the first agent approved for treatment of type 2 diabetes (T2D) that can be administered on a weekly basis.

Methods

Data concerning treatment of T2D with ExeOW are reviewed with special reference to its long-term efficacy, tolerability, and safety. Relevant literature was identified through the PubMed database from inception to January 2015.

Results

In randomized clinical trials ExeOW, as add-on to oral antidiabetics, achieved significantly improved glycemic control compared to maximum recommended doses of exenatide twice daily, sitagliptin, pioglitazone, and insulin glargine, as measured by HbA1c. In drug-naïve patients ExeOW was superior to sitagliptin and non-inferior to metformin, whereas non-inferiority to pioglitazone and liraglutide was not proven. In different trials reductions in HbA1c ranged from −1.1% to −2.0%. ExeOW therapy over 6 months was also associated with a mean weight loss of −2 to −4 kg, improved systolic blood pressure and lipid profile, and no hypoglycemia unless associated to sulfonylurea. ExeOW long-term therapy up to 3–6 years allowed persistent glycemic control (HbA1c −1.6%), sustained decreases in blood pressure (−2 mmHg), and improvements of lipid profile. ExeOW tolerability was comparable to that of the other GLP-1 receptor agonists, with better gastrointestinal tolerability when direct comparison was done (namely liraglutide and exenatide BID), but higher incidence of injection site reactions and few treatment discontinuations mainly due to gastrointestinal events.

Conclusion

ExeOW is a well-tolerated and convenient option for long-term treatment of T2D allowing significant and persistent glycemic control with moderate weight loss and low risk of hypoglycemia unless associated with sulfonylureas.

Cardiovascular benefits and safety of non-insulin medications used in the treatment of type 2 diabetes mellitus

Diabetes mellitus is a growing in exponential proportions. If the current growth trend continues, it may result in every third adult in the United States having diabetes mellitus by 2050, and every 10^th adult worldwide. Type 2 diabetes mellitus (T2DM) confers a 2- to 3-fold increased risk of cardiovascular (CV) events compared with non-diabetic patients, and CV mortality is responsible for around 80% mortality in this population. Patients with T2DM can have other features of insulin resistance-metabolic syndrome like hypertension, lipid abnormalities, and obesity which are all associated with increased CV disease and stroke risk even in the absence of T2DM. The management of a T2DM calls for employing a holistic risk factor control approach. Metformin is the first line therapy for T2DM and has been shown to have cardiovascular beneficial effects. Intense debate regarding the risk of myocardial infarction with rosiglitazone led to regulatory agencies necessitating cardiovascular outcome trials with upcoming anti-diabetic medications. Glucagon like peptide-1 agonists and sodium glucose co-transporter-2 inhibitors have shown promising CV safety and additional CV benefit in recent clinical trials. These drugs have favorable effects on traditional CV risk factors. The findings from these studies further support that fact that CV risk factor control plays an important role in reducing morbidity and mortality in T2DM patients. This review article will discuss briefly the cardiovascular safety and benefits of the oral medications which are currently being used for T2DM and will then discuss in detail about the newer medications being investigated for the treatment of T2DM.