Cardiovascular Effects of Different GLP-1 Receptor Agonists in Patients with Type 2 Diabetes

Glucagon-like peptide-1 receptor agonist treatment of high carbohydrate intake-induced metabolic syndrome provides pleiotropic effects on cardiac dysfunction through alleviations in electrical and intracellular Ca2+ abnormalities and mitochondrial dysfunction

The pleiotropic effects of glucagon-like peptide-1 receptor (GLP-1R) agonists on the heart have been recognised in obese or diabetic patients. However, little is known regarding the molecular mechanisms of these agonists in cardioprotective actions under metabolic disturbances. We evaluated the effects of GLP-1R agonist liraglutide treatment on left ventricular cardiomyocytes from high-carbohydrate induced metabolic syndrome rats (MetS rats), characterised with insulin resistance and cardiac dysfunction with a long-QT. Liraglutide (0.3 mg/kg for 4 weeks) treatment of MetS rats significantly reversed long-QT, through a shortening the prolonged action potential duration and recovering inhibited K⁺ -currents. We also determined a significant recovery in the leaky sarcoplasmic reticulum (SR) and high cytosolic Ca²⁺ -level, which are confirmed with a full recovery in activated Na⁺ /Ca²⁺ -exchanger currents (I_NCX ). Moreover, the liraglutide treatment significantly reversed the depolarised mitochondrial membrane potential (MMP), increased production of oxidant markers, and cellular acidification together with the depressed ATP production. Our light microscopy analysis of isolated cardiomyocytes showed marked recoveries in the liraglutide-treated MetS group such as marked reverses in highly dilated T-tubules and SR-mitochondria junctions. Moreover, we determined a significant increase in depressed GLUT4 protein level in liraglutide-treated MetS group, possibly associated with recovery in casein kinase 2α. Overall, the study demonstrated a molecular mechanism of liraglutide-induced cardioprotection in MetS rats, at most, via its pleiotropic effects, such as alleviation in the electrical abnormalities, Ca²⁺ -homeostasis, and mitochondrial dysfunction in ventricular cardiomyocytes.

Therapeutic potential of targeting intestinal bitter taste receptors in diabetes associated with dyslipidemia

Intestinal release of incretin hormones after food intake promotes glucose-dependent insulin secretion and regulates glucose homeostasis. The impaired incretin effects observed in the pathophysiologic abnormality of type 2 diabetes have triggered the pharmacological development of incretin-based therapy through the activation of glucagon-like peptide-1 (GLP-1) receptor, including GLP-1 receptor agonists (GLP-1 RAs) and dipeptidyl peptidase 4 (DPP4) inhibitors. In the light of the mechanisms involved in the stimulation of GLP-1 secretion, it is a fundamental question to explore whether glucose and lipid homeostasis can be manipulated by the digestive system in response to nutrient ingestion and taste perception along the gastrointestinal tract. While glucose is a potent stimulant of GLP-1 secretion, emerging evidence highlights the importance of bitter tastants in the enteroendocrine secretion of gut hormones through activation of bitter taste receptors. This review summarizes bitter chemosensation in the intestines for GLP-1 secretion and metabolic regulation based on recent advances in biological research of bitter taste receptors and preclinical and clinical investigation of bitter medicinal plants, including bitter melon, hops strobile, and berberine-containing herbs (e.g. coptis rhizome and barberry root). Multiple mechanisms of action of relevant bitter phytochemicals are discussed with the consideration of pharmacokinetic studies. Current evidence suggests that specific agonists targeting bitter taste receptors, such as human TAS2R1 and TAS2R38, may provide both metabolic benefits and anti-inflammatory effects with the modulation of the enteroendocrine hormone secretion and bile acid turnover in metabolic syndrome individuals or diabetic patients with dyslipidemia-related comorbidities.

Anti-Obesity Drugs: Long-Term Efficacy and Safety: An Updated Review

As a chronic and relapsing disease, obesity negatively impacts the health of men to a greater extent than that of women, with a higher risk of cardiovascular disease. Since lifestyle modifications alone are often challenging and limited for the maintenance of weight reduction, pharmacotherapy should be considered in a timely manner for obese men or overweight patients with weight-related comorbidities. Recent advances in anti-obesity drugs have enabled the potential of achieving clinically significant weight loss. Increasing evidence has shown that behavior-based interventions with one of these medications can result in greater weight loss than that elicited by usual care conditions. Data from most recent meta-analyses showed that the overall placebo-subtracted weight reduction (%) with the use of anti-obesity drugs for at least 12 months ranges from 2.9% to 6.8%; phentermine/topiramate (-6.8%) liraglutide (-5.4%), naltrexone/bupropion (-4.0%), lorcaserin (-3.1%), and orlistat (-2.9%). However, they have a high cost and may cause adverse outcomes depending on the individual. Very recently, on February 13, 2020, the US Food and Drug Administration requested withdrawal of lorcaserin from the market because a safety clinical trial showed an increased occurrence of cancer. Therefore the decision to initiate drug therapy in obese individuals should be made after the benefits and risks are considered. Thereafter, treatment should be tailored to specific patient subpopulations depending on their chronic conditions, comorbidities, and preferences. Herein, we provide an overview of the latest developments in weight loss medications, which may serve as one of the strategies for long-term obesity control.

Long-Term Efficacy and Safety of Anti-Obesity Treatment: Where Do We Stand?

PURPOSE OF REVIEW

As a chronic and relapsing disease, obesity impairs metabolism and causes cardiovascular diseases. Although behavioral modification is important for the treatment of obesity, it is difficult to achieve an ideal weight or sustain the process of long-term weight loss. Therefore, the obesity control guidelines strongly recommend lifestyle interventions along with medical treatment for patients who are overweight. There is sufficient evidence supporting that pharmacotherapy in combination with behavior-based interventions can result in significant weight loss and improved cardiometabolism.

RECENT FINDINGS

Recent meta-analyses of new anti-obesity drugs and their weight-loss efficacy have shown that the overall placebo-subtracted weight reduction (%) for at least 12 months ranged from 2.9 to 6.8% for the following drugs: phentermine/topiramate (6.8%), liraglutide (5.4%), naltrexone/bupropion (4.0%), orlistat (2.9%), and lorcaserin (3.1%). However, very recently, on February 13, 2020, the US Food and Drug Administration (FDA) ordered the withdrawal of lorcaserin from markets, as a clinical trial to assess drug safety showed an increased risk of cancer. Currently, the anti-obesity medications that have been approved by the FDA for chronic weight management are orlistat, phentermine/topiramate, naltrexone/bupropion, and liraglutide. However, they are costly and may have adverse effects in some individuals. Therefore, drug therapy should be initiated in obese individuals after weighing its benefits and risks. One of the strategies for long-term obesity control is that anti-obesity medications should be tailored for specific patients depending on their chronic conditions, comorbidities, and preferences.

A narrative review of current trends in liraglutide: insights into the unmet needs in management of type 2 diabetes and obesity

Liraglutide is a long-acting human glucagon-like peptide-1 (GLP-1) analogue and an effective treatment for patients with metabolic diseases including type 2 diabetes mellitus (T2DM) and obesity. This review focuses on the mechanism of action of liraglutide as a well-known glucagon-like peptide-1 receptor agonist (GLP-1 RA) in patients with T2DM and obesity. The lower and the higher doses of GLP-1 RAs are used for glycaemic control in T2DM and in obesity respectively. GLP-1 RAs such as liraglutide enhance insulin secretion and inhibit glucagon release via the stimulation of glucagon-like peptide-1 receptors (GLP-1Rs). Liraglutide decreases hemoglobin A1c (HbA1c) in type 2 diabetes (T2D) patients when prescribes as monotherapy or in combination with one or more antidiabetic drugs. Usually, it is well tolerated with minor hypoglycemia in combination therapy. Liraglutide reduces cardiovascular events and related risk factors including improvement of lipid profile and control of blood pressure. Accordingly, it can be cost-effective and may be a budget neutral medication option by considering its protective effect on the cardiovascular system in long-term use in the health care plan. In the near future, by pharmacogenomics approach, prediction of the highest patient's response with the lowest adverse drug reactions and also rationality of drug development will be possible. Liraglutide can be used as a desirable medicine for glycemic control and obesity. It shows extensive evidence based benefits in diabetes complications. In this narrative review, we have summarized and evaluated studies related to the role of liraglutide in clinical practice.

Metabolic and cardiovascular benefits of GLP-1 agonists, besides the hypoglycemic effect (Review)

Patients with type 2 diabetes exhibit higher cardiovascular risk than normal individuals. Optimal blood glucose levels are rarely achieved in diabetic patients. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have emerged as a new antidiabetic drug class with multiple metabolic effects. Some trials have evaluated their safety, but it has been recently demonstrated that this new class has cardiovascular benefits, through other mechanisms than glycemic control. The use of GLP-1RAs was associated with a significant reduction of cardiovascular and all-cause mortality, with a safe profile related to pancreatitis or thyroid cancer, as compared with placebo. This review presents the cardiovascular and metabolic benefits of GLP-1 RAs versus placebo, in patients with type 2 diabetes. Semaglutide and liraglutide demonstrated a reduction in cardiovascular events, with similar rates on cardiovascular mortality. Ongoing trials assess the cardiovascular benefits and side effects of dulaglutide treatment. Exenatide and liraglutide demonstrated the decrease of blood pressure values, weight reduction and improvement of dyslipidemia. Liraglutide induced, both in vivo and in vitro, an improvement of blood circulation, increasing the nitric oxide level and inhibiting the adhesion and procoagulant factors. Also, liraglutide demonstrated beneficial effects on cardiac remodeling after myocardial infarction, but more large trials are required. However, the international guidelines recommend using GLP-1 RAs as first-line therapy in type 2 diabetes patients with high cardiovascular risk or as first-line agents in patients intolerant to metformin.

Suitable Use of Injectable Agents to Overcome Hypoglycemia Risk, Barriers, and Clinical Inertia in Community-Dwelling Older Adults with Type 2 Diabetes Mellitus

The management of type 2 diabetes mellitus in older adults requires a comprehensive understanding of the relationship between the disease (medical) and the functional, psychological/cognitive, and social geriatric domains, to individualize both glycemic targets and therapeutic approaches. Prevention of hypoglycemia is a major priority that should be addressed as soon as its presence or risk is detected, adjusting the target and therapeutics accordingly. Nonetheless, treatment intensification should not be neglected when applicable, consistent with recommendations from organizations such as the American Geriatrics Society and the American Diabetes Association, to reduce not only long-term macrovascular and microvascular complications (individualization), but also short-term complications from hyperglycemia (polyuria, volume depletion, urinary incontinence). Such complications can negatively impact the physical and cognitive function of older adults, worsen their quality of life, and additionally affect their families and society. We emphasize individualization, utilizing the multiple classes of antihyperglycemic agents available. Metformin remains as first-line therapy, and additional agents offer advantages and disadvantages that ought to be considered when developing a patient-centric plan of care. For selected cases, injectable therapies such as long-acting basal insulin analogs and glucagon-like peptide-1 receptor agonists can offer advantages to counter hypoglycemia risk, patient-related barriers, and clinical inertia. Furthermore, some injectable agents could potentially simplify regimens while providing safe and effective glycemic control. In this review, we discuss the use of injectable therapies for selected community-dwelling older adults, barriers to transition to injectable therapy, and measures aimed at removing these barriers and assisting physicians and their teams to transition older patients to injectable therapies when appropriate.

Treatment With Liraglutide Exerts Neuroprotection After Hypoxic-Ischemic Brain Injury in Neonatal Rats via the PI3K/AKT/GSK3β Pathway

Neonatal hypoxic–ischemic (HI) brain injury is a detrimental disease, which results in high mortality and long-term neurological deficits. Nevertheless, the treatment options for this disease are limited. Thus, the aim of the present study was to assess the role of liraglutide in neonatal HI brain injury in rats and investigate the associated mechanisms. The results showed that treatment with liraglutide significantly reduced infarct volume and ameliorated cerebral edema, decreased inflammatory response, promoted the recovery of tissue structure, and improved prognosis following HI brain injury. Moreover, treatment with liraglutide inhibited apoptosis and promoted neuronal survival both in the rat model and following oxygen-glucose deprivation (OGD) insult. LY294002, an inhibitor of phosphoinositide 3-kinase (PI3K), partially reversed these therapeutic effects, suggesting that the PI3K/protein kinase B (Akt) pathway was involved. In conclusion, our data revealed that treatment with liraglutide exerts neuroprotection after neonatal HI brain injury via the PI3K/Akt/glycogen synthase kinase-3β (GSK3β) pathway and may be a promising therapy for this disease.

Medications for the treatment of obesity in adolescents

While there are eight medications/combinations approved for the treatment of obesity in adults, the options for the treatment of obesity in adolescents remain limited. Evidence for obesity medication use in adolescents is limited due to the relatively small number of clinical trials that have been completed and the few adolescents that have been included in many of the trials. The goal of this review will be to present the current evidence for the medications approved for adolescents, medications not approved for adolescents but have adolescent data, and medications approved for adults with the prospect for use in adolescents. We will also discuss current limitations and next steps in the exploration of future treatment options.

Glucagon-Like Peptide-1 Receptor Analogues in Type 2 Diabetes: Their Use and Differential Features

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are well established as effective adjuncts to lifestyle modification in the treatment of type 2 diabetes (T2D) as monotherapy or in combination with oral glucose-lowering drugs ± insulin. The six subcutaneous GLP-1RA formulations (i.e. twice-daily exenatide, once-daily liraglutide and lixisenatide, and once-weekly dulaglutide, exenatide and semaglutide) currently available in the EU and USA have many similarities, but also some unique features and properties. By stimulating GLP-1 receptors, GLP-1RAs increase insulin secretion and suppress glucagon release in a glucose-dependent manner, thereby improving clinical and patient-reported outcomes related to glycaemic control and weight. They also have been shown to reduce, or at least not increase, the risk of major cardiovascular outcomes. GLP-1RAs are generally well tolerated, with gastrointestinal and injection-site reactions being the most troublesome drug-related adverse events, and are associated with a very low intrinsic risk of hypoglycaemia. Treatment with GLP-1RAs should be customized to meet the clinical needs and personal preferences of the individual.

Heterogeneity and Similarities in GLP-1 Receptor Agonist Cardiovascular Outcomes Trials

The latest recommendations from the American Diabetes Association and the European Association for the Study of Diabetes prioritize the use of drugs with proven cardiovascular (CV) benefit in patients with established CV disease. Especially among the glucagon-like peptide (GLP)-1 receptor agonists (GLP-1RA) class, results of cardiovascular outcomes trials (CVOT) have been heterogeneous. Baseline characteristics of the population, study design, drugs in the control arm, modifications of CV risk factors, including glycemic control, reduction of hypoglycemia, and the GLP-1RA direct effects on CV cells and tissues, were considered. Ultimately, the time of exposure to the GLP-1RA appears to be the factor most prominently explaining trial heterogeneity. Thus, the CV benefit should be regarded as a class effect of GLP-1RA, as largely similar results are seen for drugs sharing a common mechanism of action.

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.

Cigarette smoking, type 2 diabetes mellitus, and glucagon-like peptide-1 receptor agonists as a potential treatment for smokers with diabetes: An integrative review

Tobacco use disorder (TUD), in particular cigarette smoking, contributes significantly to the macro- and micro-vascular complications of type 2 diabetes mellitus (DM). Persons with DM who regularly use tobacco products are twice as likely to experience mortality and negative health outcomes. Despite these risks, TUD remains prevalent in persons with DM. The objective of this integrative review is to summarize the relationship between TUD and DM based on epidemiological and preclinical biological evidence. We conclude with a review of the literature on the glucagon-like peptide-1 (GLP-1) as a potential treatment target for addressing comorbid TUD in smokers with DM.

Pharmacotherapy of obesity: Available medications and drugs under investigation

Obesity is a chronic disease with a continuously rising prevalence that currently affects more than half a billion people worldwide. Energy balance and appetite are highly regulated via central and peripheral mechanisms, and weight loss triggers a homeostatic response leading to weight regain. Lifestyle and behavioral modifications are the cornerstones of obesity management; however, they often fail to achieve or sustain long-term weight loss. Pharmacotherapy added onto lifestyle modifications results in an additional, albeit limited, weight reduction. Regardless, this weight reduction of 5-10% conveys multiple cardiovascular and metabolic benefits. In this review, evidence on the food and drug administration (FDA)-approved medications, i.e., orlistat, lorcaserin, phentermine/topiramate, liraglutide and naltrexone/bupropion, is summarized. Furthermore, anti-obesity agents in the pipeline for potential future therapeutic use are presented.