Development and potential role of type-2 sodium-glucose transporter inhibitors for management of type 2 diabetes

SGLT2 inhibitors: Beyond glycemic control

Multiple randomized controlled trials have extensively examined the therapeutic effectiveness of sodium-glucose cotransporter 2 (SGLT2) inhibitors, ushering in a transformative approach to treating individuals with type 2 diabetes mellitus (DM). Notably, emerging reports have drawn attention to the potential positive impacts of SGLT2 inhibitors in nondiabetic patients. In an effort to delve into this phenomenon, a comprehensive systematic literature review spanning PubMed (NLM), Medline (Ovid), and Cochrane Library, covering publications from 2000 to 2024 was undertaken. This systematic review encompassed twenty-six randomized control trials (RCTs) involving 35,317 participants. The findings unveiled a multifaceted role for SGLT2 inhibitors, showcasing their ability to enhance metabolic control and yield cardioprotective effects through a reduction in cardiovascular death (CVD) and hospitalization related to heart failure (HF). Additionally, a renalprotective effect was observed, evidenced by a slowdown in chronic kidney disease (CKD) progression and a decrease in albuminuria. Importantly, these benefits were coupled with an acceptable safety profile. The literature also points to various biological plausibility and underlying mechanistic pathways, offering insights into the association between SGLT2 inhibitors and these positive outcomes in nondiabetic individuals. Current research trends indicate a continual exploration of additional role for SGLT2 inhibitors in. Nevertheless, further research is imperative to fully elucidate the mechanisms and long-term outcomes associated with the nondiabetic use of SGLT2 inhibitors.

Sotagliflozin attenuates cardiac dysfunction and remodeling in myocardial infarction rats

Objective

Sotagliflozin is a dual sodium-glucose co-transporter-1 and 2 (SGLT1/2) inhibitor with selectivity towards SGLT2. Previous studies showed that SGLT2 inhibitors can improve cardiac function and reduce myocardial infarction size in animal models of myocardial infarction (MI). However, it remains unknown whether the dual inhibition of SGLT1/2 by sotagliflozin has beneficial effects in this context. In this study, we investigated the potential cardioprotective effects of sotagliflozin in an animal model of MI.

Methods

Sprague Dawley (SD) rats underwent left anterior descending coronary artery ligation or sham ligation then were randomly assigned to receive either sotagliflozin (10 mg/kg) or vehicle via intraperitoneal injection. Fourteen days post-MI, we assessed cardiac function using echocardiography and evaluated histological and molecular markers of cardiac remodeling and inflammation in the left ventricle.

Results

Our findings indicate that sotagliflozin treatment resulted in improved cardiac function and reduced infarct size compared with the vehicle-treated group. Additionally, sotagliflozin improved cardiac remodeling as shown by the decreased cardiac hypertrophy and cardiac apoptosis in the post-MI heart. Mechanistically, an apparent reduction in the cardiac inflammatory response in sotagliflozin-treated hearts was observed in the post-MI rats.

Conclusion

Overall, our results suggest that sotagliflozin may have cardioprotective effects against myocardial infarction.

SGLT1: A Potential Drug Target for Cardiovascular Disease

SGLT1 and SGLT2 are the two main members of the sodium-glucose cotransporters (SGLTs), which are mainly responsible for glucose reabsorption in the body. In recent years, many large clinical trials have shown that SGLT2 inhibitors have cardiovascular protection for diabetic and non-diabetic patients independent of lowering blood glucose. However, SGLT2 was barely detected in the hearts of humans and animals, while SGLT1 was highly expressed in myocardium. As SGLT2 inhibitors also have a moderate inhibitory effect on SGLT1, the cardiovascular protection of SGLT2 inhibitors may be due to SGLT1 inhibition. SGLT1 expression is associated with pathological processes such as cardiac oxidative stress, inflammation, fibrosis, and cell apoptosis, as well as mitochondrial dysfunction. The purpose of this review is to summarize the protective effects of SGLT1 inhibition on hearts in various cell types, including cardiomyocytes, endothelial cells, and fibroblasts in preclinical studies, and to highlight the underlying molecular mechanisms of protection against cardiovascular diseases. Selective SGLT1 inhibitors could be considered a class of drugs for cardiac-specific therapy in the future.

A model-based meta analysis study of sodium glucose co-transporter-2 inhibitors

Type 2 diabetes mellitus (T2DM) agent sodium-glucose co-transporter 2 (SGLT2) inhibitors show special benefits in reducing body weight and heart failure risks. To accelerate clinical development for novel SGLT2 inhibitors, a quantitative relationship among pharmacokinetics, pharmacodynamics, and disease end points (PK/PD/end points) in healthy subjects and patients with T2DM was developed. PK/PD/end point data in published clinical studies for three globally marketed SGLT2 inhibitors (dapagliflozin, canagliflozin, and empagliflozin) were collected according to pre-set criteria. Overall, 80 papers with 880 PK, 27 PD, 848 fasting plasma glucose (FPG), and 1219 hemoglobin A1c (HbA1c) data were collected. A two-compartmental model with Hill's equation was utilized to capture PK/PD profiles. A novel translational biomarker, the change of urine glucose excretion (UGE) from baseline normalized by FPG (ΔUGE_c ) was identified to bridge healthy subjects and patients with T2DM with different disease statuses. ΔUGE_c was found to have a similar maximum increase with different half-maximal effective concentration values of 56.6, 2310, and 841 mg/mL·h for dapagliflozin, canagliflozin, and empagliflozin respectively. ΔUGE_c will change FPG based on linear function. HbA1c profiles were captured by indirect response model. Additional placebo effect was also considered for both end points. The PK/ΔUGE_c /FPG/HbA1c relationship was validated internally using diagnostic plots and visual assessment and further validated externally using the fourth globally approved same-in-class drug (ertugliflozin). This validated quantitative PK/PD/end point relationship offers novel insight into long-term efficacy prediction for SGLT2 inhibitors. The novelty identified ΔUGE_c could make the comparison of different SGLT2 inhibitors' efficacy characteristics easier, and achieve early prediction from healthy subjects to patients.

Role of Sodium-Glucose Co-Transporter 2 Inhibitors in the Regulation of Inflammatory Processes in Animal Models

Sodium-glucose co-transporter 2 inhibitors, also known as gliflozins, were developed as a novel class of anti-diabetic agents that promote glycosuria through the prevention of glucose reabsorption in the proximal tubule by sodium-glucose co-transporter 2. Beyond the regulation of glucose homeostasis, they resulted as being effective in different clinical trials in patients with heart failure, showing a strong cardio-renal protective effect in diabetic, but also in non-diabetic patients, which highlights the possible existence of other mechanisms through which gliflozins could be exerting their action. So far, different gliflozins have been approved for their therapeutic use in T2DM, heart failure, and diabetic kidney disease in different countries, all of them being diseases that have in common a deregulation of the inflammatory process associated with the pathology, which perpetuates and worsens the disease. This inflammatory deregulation has been observed in many other diseases, which led the scientific community to have a growing interest in the understanding of the biological processes that lead to or control inflammation deregulation in order to be able to identify potential therapeutic targets that could revert this situation and contribute to the amelioration of the disease. In this line, recent studies showed that gliflozins also act as an anti-inflammatory drug, and have been proposed as a useful strategy to treat other diseases linked to inflammation in addition to cardio-renal diseases, such as diabetes, obesity, atherosclerosis, or non-alcoholic fatty liver disease. In this work, we will review recent studies regarding the role of the main sodium-glucose co-transporter 2 inhibitors in the control of inflammation.

Comparison of New Oral Hypoglycemic Agents on Risk of Urinary Tract and Genital Infections in Type 2 Diabetes: A Network Meta-analysis

INTRODUCTION

Dipeptidyl peptidase 4 (DPP4) inhibitors and sodium-glucose co-transporter 2 (SGLT2) inhibitors have often been used for patients with T2DM because of the reduced risk of hypoglycemia. However, DPP4 inhibitors and SGLT2 inhibitors may increase the risk of infectious diseases. This network meta-analysis (NMA) was performed to investigate the risk of urinary tract and genital infections associated with the use of two new glucose-lowering drug classes in patients with type 2 diabetes.

METHODS

PubMed, Web of Science, Embase, and the Cochrane Library were comprehensively searched for articles from the date of database inception until September 8, 2020. Placebo-controlled or head-to-head trials of the two new drug classes used for treatment of adults with type 2 diabetes were included. The primary outcome was the incidence of any confirmed urinary tract infection; genital infection was also used as an important outcome indicator.

RESULTS

Fifty-five studies were identified, covering 29,574 participants. Regarding urinary tract infections, SGLT2 inhibitors were not associated with increased risk, and among all drugs, sitagliptin, ipragliflozin, and linagliptin were the safest according to probability ranking. Regarding genital infections, saxagliptin was associated with significantly reduced risk in pairwise comparisons with placebo (RR 0.12, 95% CI 0.00-0.78), linagliptin (RR 0.09, 95% CI 0.00-0.78), canagliflozin (RR 0.04, 95% CI 0.00-0.31), dapagliflozin (RR 0.04, 95% CI 0.00-0.26), empagliflozin (RR 0.03, 95% CI 0.00-0.25), and ertugliflozin (RR 0.03, 95% CI 0.00-0.24). Among all drugs, saxagliptin, sitagliptin, and ipragliflozin were the safest according to probability ranking. Considering both urinary tract and genital infection risks, DPP4 inhibitors showed greater reductions than SGLT2 inhibitors and placebo. Saxagliptin was the safest drug according to probability ranking for both infection risks.

CONCLUSIONS

This NMA showed that, to reduce genital infection risk, current evidence favors DPP4 inhibitors over SGLT2 inhibitors. Most SGLT2 inhibitors may not be associated with the risk of urinary tract infections. Considering both infection risks, saxagliptin may be the safest drug. Finally, mechanistic studies are needed to better understand the physiological basis for these effects.

Diabetes and Its Complications: Therapies Available, Anticipated and Aspired

Worldwide, diabetes ranks among the ten leading causes of mortality. Prevalence of diabetes is growing rapidly in low and middle income countries. It is a progressive disease leading to serious co-morbidities, which results in increased cost of treatment and over-all health system of the country. Pathophysiological alterations in Type 2 Diabetes (T2D) progressed from a simple disturbance in the functioning of the pancreas to triumvirate to ominous octet to egregious eleven to dirty dozen model. Due to complex interplay of multiple hormones in T2D, there may be multifaceted approach in its management. The 'long-term secondary complications' in uncontrolled diabetes may affect almost every organ of the body, and finally may lead to multi-organ dysfunction. Available therapies are inconsistent in maintaining long term glycemic control and their long term use may be associated with adverse effects. There is need for newer drugs, not only for glycemic control but also for prevention or mitigation of secondary microvascular and macrovascular complications. Increased knowledge of the pathophysiology of diabetes has contributed to the development of novel treatments. Several new agents like Glucagon Like Peptide - 1 (GLP-1) agonists, Dipeptidyl Peptidase IV (DPP-4) inhibitors, amylin analogues, Sodium-Glucose transport -2 (SGLT- 2) inhibitors and dual Peroxisome Proliferator-Activated Receptor (PPAR) agonists are available or will be available soon, thus extending the range of therapy for T2D, thereby preventing its long term complications. The article discusses the pathophysiology of diabetes along with its comorbidities, with a focus on existing and novel upcoming antidiabetic drugs which are under investigation. It also dives deep to deliberate upon the novel therapies that are in various stages of development. Adding new options with new mechanisms of action to the treatment armamentarium of diabetes may eventually help improve outcomes and reduce its economic burden.

SGLT1 inhibition boon or bane for diabetes-associated cardiomyopathy

Chronic hyperglycaemia is a peculiar feature of diabetes mellitus (DM). Sequential metabolic abnormalities accompanying glucotoxicity are some of its implications. Glucotoxicity most likely corresponds to the vascular intricacy and metabolic alterations, such as increased oxidation of free fatty acids and reduced glucose oxidation. More than half of those with diabetes also develop cardiac abnormalities due to unknown causes, posing a major threat to the currently available marketed preparations which are being used for treating these cardiac complications. Even though impairment in cardiac functioning is the principal cause of death in individuals with type 2 diabetes (T2D), reducing plasma glucose levels has little effect on cardiovascular disease (CVD) risk. In vitro and in vivo studies have demonstrated that inhibitors of sodium glucose transporter (SGLT) represent a putative therapeutic intervention for these pathological conditions. Several clinical trials have reported the efficacy of SGLT inhibitors as a novel and potent antidiabetic agent which along with its antihyperglycaemic activity possesses the potential of effectively treating its associated cardiac abnormalities. Thus, hereby, the present review highlights the role of SGLT inhibitors as a successful drug candidate for correcting the shifts in deregulation of cardiac energy substrate metabolism together with its role in treating diabetes-related cardiac perturbations.

A Strength-Weaknesses-Opportunities-Threats (SWOT) Analysis of Cheminformatics in Natural Product Research

Cheminformatics-based techniques, such as molecular modeling, docking, virtual screening, and machine learning, are well accepted for their usefulness in drug discovery and development of therapeutically relevant small molecules. Although delayed by several decades, their application in natural product research has led to outstanding findings. Combining information obtained from different sources, i.e., virtual predictions, traditional medicine, structural, biochemical, and biological data, and handling big data effectively will open up new possibilities, but also challenges in the future. Strategies and examples will be presented on how to integrate cheminformatics in pharmacognostic workflows to benefit from these two highly complementary disciplines toward streamlining experimental efforts. While considering their limits and pitfalls and by exploiting their potential, computer-aided strategies should successfully guide future studies and thereby augment our knowledge of bioactive natural lead structures.

SGLT-2 Inhibitors and Cardiovascular Protection: Lessons and Gaps in Understanding the Current Outcome Trials and Possible Benefits of Combining SGLT-2 Inhibitors With GLP-1 Agonists

Landmark trials on diabetes control have shown variable results in terms of cardiovascular benefits, with the majority showing a favorable effect of glycemic control on microvascular and, more recently, macrovascular complications. However, some trials pointed out a CV hazard with tight diabetes mellitus (DM) control. Most of those trials were assessing the impact of glycemic control, more than evaluating the effect of a certain medication. In the last decade, food and drugs administration (FDA) has mandated that all new hypoglycemic agents run a CV outcome trial (CVOT) for safety in order to grant and sustain approval. The most stunning results came from relatively new agents in the field of diabetes management, sodium-glucose cotransporter-2 inhibitors (SGLT2i) and the glucagon-like peptide-1 agonists (GLP-1 agonists), details of these CVOTs will be addressed later in this document. SGLT2i effect on the cardiovascular system remains an area of extensive research. We aimed in this review to summarize what is the current evidence of cardiovascular protection upon using SGLT2i. Moreover, we wanted to raise a point that may be strongly adopted in the future, combining SGLT2i plus GLP-1 agonists, having a cardiovascular privilege in both molecules.

Tolerability and Efficacy of Ipragliflozin in The Management of Inadequately Controlled Type 2 Diabetes mellitus: A Systematic Review and Meta-analysis

AIM

Ipragliflozin is a new antidiabetic agent that works through enhancing renal glucose excretion. We aim to synthesize evidence from published randomized controlled trials (RCTs) on the safety and efficacy of ipragliflozin in the management of type 2 diabetes mellitus (T2DM).

METHODS

We searched PubMed, Scopus, Web of Science, and Cochrane Central register of clinical trials using relevant keywords. Records were screened for eligible studies and data were extracted and synthesized using Review Manager Version 5.3 for windows. Subgroup and sensitivity analyses were conducted.

RESULTS

We included 13 RCTs (N=2535 patients) in the final analysis. The overall effect estimates favoured ipragliflozin 50mg monotherapy group over placebo in terms of: HbA1c (Standardized mean difference (SMD)=-1.20%, 95% Confidence interval (95% CI)=[-1.47, -0.93]; p<0.001), fasting plasma glucose (SMD=-1.30 mg/dL, 95% CI [-1.93, -0.67]; p<0.001), fasting serum insulin (SMD=-1.64 μU/mL, 95% CI [-2.70, -0.59]; p=0.002), and body weight (SMD=-0.85 kg, 95% CI [-1.19, -0.51]; p<0.001). Similarly, better glycemic control and significant body weight reduction compared to placebo were attained in ipragliflozin 50 mg combination with metformin, insulin with/without dipeptidyl peptidase-4 inhibitor, sulfonylurea, and pioglitazone. Ipragliflozin, either alone or in combination, exhibits acceptable safety profile.

CONCLUSION

The presented meta-analysis provides class one evidence that ipragliflozin is safe and effective in the management of T2DM either as monotherapy or an add-on.

Plasma Pharmacokinetic Determination of Canagliflozin and Its Metabolites in a Type 2 Diabetic Rat Model by UPLC-MS/MS

Canagliflozin is a novel, orally selective inhibitor of sodium-dependent glucose co-transporter-2 (SGLT2) for the treatment of patients with type 2 diabetes mellitus. In this study, a sensitive and efficient UPLC-MS/MS method for the quantification of canagliflozin and its metabolites in rat plasma was established and applied to pharmacokinetics in a type 2 diabetic rat model. We firstly investigated the pharmacokinetic changes of canagliflozin and its metabolites in type 2 diabetic rats in order to use canagliflozin more safely, reasonably and effectively. We identified three types of O-glucuronide metabolites (M5, M7 and M17), two kinds of oxidation metabolites (M8 and M9) and one oxidation and glucuronide metabolite (M16) using API 5600 triple-TOF-MS/MS. Following liquid–liquid extraction by tert-butyl methyl ether, chromatographic separation of canagliflozin and its metabolites were performed on a Waters XBridge BEH C18 column (100 × 2.1 mm, 2.5 μm) using 0.1% acetonitrile–formic acid (75:15, v/v) as the mobile phase at a flow rate of 0.7 mL/min. Selected ion monitoring transitions of m/z 462.00→191.10, 451.20→153.10, 638.10→191.10 and 478.00→267.00 were chosen to quantify canagliflozin, empagliflozin (IS), O-glucuronide metabolites (M5, M7 and M17), and oxidation metabolites (M9) using an API 5500-triple-MS/MS in the positive electrospray ionization mode. The validation of the method was found to be of sufficient specificity, accuracy and precision. The pathological condition of diabetes could result in altered pharmacokinetic behaviors of canagliflozin and its metabolites. The pharmacokinetic parameters (AUC_0–t, AUC_0–∞, CL_z/F, and V_z/F) of canagliflozin were significantly different between the CTRL and DM group rats (p < 0.05 or p < 0.01), which may subsequently cause different therapeutic effects.

Use of SGLT-2 inhibitors in the treatment of type 2 diabetes mellitus

INTRODUCTION

Diabetes mellitus is one of the most common chronic diseases in the world, with high morbidity and mortality rates, resulting in a greatly negative socioeconomic impact. Although there are several classes of oral antidiabetic agents, most of the patients are outside the therapeutic goal range.

OBJECTIVE

To review the use of SGLT-2 inhibitors in the treatment of type 2 diabetes mellitus, focusing on their favorable and unfavorable effects, as well as on cardiovascular profile.

METHOD

A literature search on Pubmed database was performed using the following keywords: "SGLT-2 inhibitors," "dapagliflozin," "empagliflozin," "canagliflozin."

RESULTS

SGLT-2 inhibitors are a class of oral antidiabetic drugs directed to the kidney. Their mechanism of action is to reduce blood glucose by inducing glycosuria. Extra-glycemic benefits have been described, such as weight loss, decline in blood pressure and levels of triglycerides and uric acid, and they can slow the progression of kidney disease. Genitourinary infections are the main side effects. There is a low risk of hypotension and hypoglycemia. Diabetic ketoacidosis is a serious adverse effect, although rare. Empagliflozin has already had its cardiovascular benefit demonstrated and studies with other drugs are currently being performed.

CONCLUSION

SGLT-2 inhibitors are a new treatment option for type 2 diabetes mellitus, acting independently of insulin. They have potential benefits other than the reduction of blood glucose, but also carry a risk for adverse effects.

Comparisons of weight changes between sodium-glucose cotransporter 2 inhibitors treatment and glucagon-like peptide-1 analogs treatment in type 2 diabetes patients: A meta-analysis

AIMS/INTRODUCTION

To evaluate the efficacy of weight changes from baseline of the sodium-glucose cotransporter 2 (SGLT2) inhibitors treatment and glucagon-like peptide-1 (GLP-1) analogs treatment after comparisons with a placebo in type 2 diabetes patients, and the associated factors.

MATERIALS AND METHODS

Studies were searched from when recording began, June 2004, until June 2015, and re-searched in July 2016, and placebo-controlled randomized trials in type 2 diabetes patients with a study length of ≥12 weeks were included.

RESULTS

A total of 97 randomized controlled trials were included. Compared with a placebo, treatment with SGLT2 inhibitors was associated with a significantly greater decrease in weight change from baseline (weighted mean differences -2.01 kg, 95% confidence interval -2.18 to -1.83 kg, P < 0.001). Compared with a placebo, changes with GLP -1 treatment were also associated with a comparable decrease in weight change from baseline (weighted mean differences -1.59 kg, 95% confidence interval -1.86 to -1.32 kg, P < 0.001). Meta-regression analysis showed that the baseline age, sex, baseline glycated hemoglobin, diabetes duration or baseline body mass index were not associated with the weight change from baseline in SGLT2 inhibitors or in GLP-1 treatment corrected by placebo. Comparisons of weight changes from baseline corrected by placebo between SGLT2 inhibitors and GLP-1 treatment showed that the difference was not significant (P > 0.05).

CONCLUSIONS

According to the present meta-analysis, treatment with SGLT2 inhibitors and treatment with GLP-1 analogs led to comparable weight changes from baseline, which are both with significance when compared with placebo treatment.

Long-term efficacy and safety of sodium-glucose cotransporter-2 inhibitors as add-on to metformin treatment in the management of type 2 diabetes mellitus: A meta-analysis

BACKGROUND

Drug intensification is often required for patients with type 2 diabetes mellitus on stable metformin therapy. Among the potential candidates for a combination therapy, sodium-glucose transporter-2 (SGLT2) inhibitors have shown promising outcomes. This meta-analysis was performed to compare the efficacy and safety of SGLT2 inhibitors with non-SGLT2 combinations as add-on treatment to metformin.

METHODS

Literature search was carried out in multiple electronic databases for the acquisition of relevant randomized controlled trials (RCTs) by following a priori eligibility criteria. After the assessment of quality of the included RCTs, meta-analyses of mean differences or odds ratios (OR) were performed to achieve overall effect sizes of the changes from baseline in selected efficacy and safety endpoints reported in the individual studies. Between-studies heterogeneity was estimated with between-studies statistical heterogeneity (I) index.

RESULTS

Six RCTs fulfilled the eligibility criteria. SGLT2 inhibitors as add-on to metformin treatment reduced % HbA1c significantly more than non-SGLT2 combinations after 52 weeks (P = .002) as well as after 104 weeks (P < .00001). Among other endpoints, SGLT2 inhibitors also reduced fasting plasma glucose levels, body weight, systolic, and diastolic blood pressures after 52 weeks and 104 weeks significantly (P < .00001) more than non-SGLT2 combinations. Incidence of hypoglycemia was significantly lower (P = .02) but incidence of suspected or confirmed genital tract infections was significantly higher (P < .00001) in SGLT2 inhibitors treated in comparison with non-SGLT2 combinations.

CONCLUSION

As add-on to metformin treatment, SGLT2 inhibitors are found significantly more efficacious than non-SGLT2 inhibitor combinations in the management of type 2 diabetes mellitus, although, SGLT2 inhibitor therapy is associated with significantly higher incidence of suspected or confirmed genital tract infections.

Basal insulin treatment intensification in patients with type 2 diabetes mellitus: A comprehensive systematic review of current options

AIM

As type 2 diabetes mellitus progresses, most patients require treatment with basal insulin in combination with another agent to achieve recommended glycaemic targets. The purpose of this systematic review was to examine the evidence supporting the use of the available add-on treatments [rapid-acting insulin (RAI), glucagon-like peptide-1 receptor agonists (GLP-1 RAs), dipeptidyl peptidase (DPP)-4 inhibitors and sodium-glucose cotransporter-2 (SGLT-2) inhibitors] to basal insulin.

METHODS

MEDLINE, EMBASE and EBSCOhost were searched for English-language articles, and all those captured were original articles (case studies and narrative reviews were omitted). Data on study design, population demographics, interventions and outcomes were tabulated. The extracted outcome data included changes in glycated haemoglobin (HbA_1c), fasting plasma glucose (FPG) and postprandial plasma glucose (PPG), as well as body weight and safety data.

RESULTS

A total of 88 publications were deemed relevant. All treatments reduced HbA_1c and FPG. The most pronounced reductions in PPG, an unmet need in patients not controlled by basal insulin, were seen following administration of RAIs and short-acting GLP-1 RAs, although data for this outcome are generally lacking. Body weight benefits were observed with GLP-1 RAs and SGLT-2 inhibitors. However, as only articles in English were included, the result was a possible publication bias, while the diversity of study designs and drug combinations limited comparisons between studies.

CONCLUSION

The evidence supports effectiveness of the available add-on treatments to basal insulin. However, other factors, such as potential body-weight increases, convenience/compliance and adverse events, particularly hypoglycaemia, should be considered on a patient-by-patient basis to optimalize treatment outcomes.

Targeting glucose metabolism for healthy aging

Advancing age is the greatest single risk factor for numerous chronic diseases. Thus, the ability to target the aging process can facilitate improved healthspan and potentially lifespan. Lack of adequate glucoregulatory control remains a recurrent theme accompanying aging and chronic disease, while numerous longevity interventions result in maintenance of glucoregulatory control. In this review, we propose targeting glucose metabolism to enhance regulatory control as a means to ameliorate the aging process. We highlight that calorie restriction improves glucoregulatory control and extends both lifespan and healthspan in model organisms, but we also indicate more practical interventions (i.e., calorie restriction mimetics) are desirable for clinical application in humans. Of the calorie restriction mimetics being investigated, we focus on the type 2 diabetes drug acarbose, an α-glucosidase inhibitor that when taken with a meal, results in reduced enzymatic degradation and absorption of glucose from complex carbohydrates. We discuss alternatives to acarbose that yield similar physiologic effects and describe dietary sources (e.g., sweet potatoes, legumes, and berries) of bioactive compounds with α-glucosidase inhibitory activity. We indicate future research should include exploration of how non-caloric compounds like α-glucosidase inhibitors modify macronutrient metabolism prior to disease onset, which may guide nutritional/lifestyle interventions to support health and reduce age-related disease risk.

Treatment intensification in patients with inadequate glycemic control on basal insulin: rationale and clinical evidence for the use of short-acting and other glucagon-like peptide-1 receptor agonists

A substantial proportion of patients with type 2 diabetes mellitus do not reach glycemic targets, despite treatment with oral anti-diabetic drugs and basal insulin therapy. Several options exist for treatment intensification beyond basal insulin, and the treatment paradigm is complex. In this review, the options for treatment intensification will be explored, focusing on drug classes that act via the incretin system and paying particular attention to the short-acting glucagon-like peptide-1 receptor agonists exenatide and lixisenatide. Current treatment guidelines will be summarized and discussed. © 2016 The Authors. Diabetes/Metabolism Research and Reviews Published by John Wiley & Sons Ltd.

Efficacy and safety of sodium-glucose cotransporter 2 inhibitors in type 2 diabetes: a meta-analysis of randomized controlled trials for 1 to 2years

AIMS

To evaluate the mid long-term efficacy and safety of sodium-glucose cotransporter 2 (SGLT2) inhibitors in adults with type 2 diabetes mellitus (T2DM).

METHODS

Three databases including Pubmed, Embase, and Cochrane Library were searched for randomized controlled trials (RCTs) of SGLT2 inhibitors that lasted for at least 52weeks. Two reviewers retrieved the literature and evaluated study quality using the Modified Jadad Score Scale. The outcome measures were pooled using random or fixed effects models.

RESULTS

Fourteen articles of 13 RCTs were included in this meta-analysis. Compared to a placebo, the SGLT2 inhibitors significantly reduced glycated hemoglobin (HbA1c) [for 1year result, weighted mean differences (WMDs): -0.491%; 95% confidence intervals (CIs): -0.573 to -0.410; I(2)=39.9%, for 2years result, WMD: -0.503%; 95% CI: -0.742 to -0.265; I(2)=70.7%], fasting plasma glucose (FPG) (for 1year result, WMD: -0.809; 95% CI: -0.858 to -0.761; I(2)=56.4%; for 2years result, WMD: -0.764; 95% CI: -1.026 to -0.501; I(2)=39.4%), body weight (BW) (for 1year result, WMD: -2.477; 95% CI: -2.568 to -2.385; I(2)=0.0%; for 2years result, WMD: -2.990; 95% CI: -3.642 to -2.337; I(2)=0.0%), systolic blood pressure (SBP) (for 1year result, WMD: -2.874; 95% CI: -4.528 to -1.220; I(2)=98.1%; for 2years result, WMD: -7.500; 95% CI: -7.698 to -7.302) and diastolic blood pressure (DBP) (for 1year result, WMD: -1.950; 95% CI: -2.890 to -1.010; I(2)=98.0%; for 2years result, WMD: -2.197; 95% CI: -3.112 to -1.283). Compared to oral antidiabetic drugs (OADs), the SGLT2 inhibitors also reduced HbA1c, FPG, BW, SBP and DBP significantly. Compared to a placebo, the SGLT2 inhibitors increase the risk of hypoglycemia [odds ratios (ORs): 1.214; 95% CI: 1.036 to 1.423; I(2)=47.7%], urinary infection (OR: 1.477; 95% CI: 1.172 to 1.861; I(2)=46.6%) and genital tract infections (OR: 4.196; 95% CI: 2.332 to 7.549; I(2)=52.7%). Compared to OADs, SGLT2 inhibitors showed a remarkable reduction of hypoglycemia incidence (OR: 0.202; 95% CI: 0.059 to 0.691; I(2)=97.8%), but increased the incidence of genital tract infections (OR: 5.715; 95% CI: 4.339 to 7.528; I(2)=0.0%) and urinary infection (OR: 1.192; 95% CI: 0.990 to 1.434; I(2)=45.3%). SGLT2 inhibitors did not decrease estimated glomerular filtration rate (eGFR) when comparing with placebos [(for absolute value change, WMD: 0.629mL/min/1.73m(2); 95% CI: -1.250 to 2.508; I(2)=0.0%); (for percent change, WMD: -2.274%; 95% CI: -5.410 to 0.861; I(2)=54.5%)] and OADs (for percent change, WMD: 0.356%; 95% CI: -0.967 to 1.679; I(2)=0.0%).

CONCLUSION

SGLT2 inhibitors have favorable effects on combating hyperglycemia for mid long-term; likewise, they have additional benefits beyond glycemic control such as reducing body weight and lowering blood pressure.

Addressing unmet medical needs in type 2 diabetes: a narrative review of drugs under development

The global burden of type 2 diabetes is increasing worldwide, and successful treatment of this disease needs constant provision of new drugs. Twelve classes of antidiabetic drugs are currently available, and many new drugs are under clinical development. These include compounds with known mechanisms of action but unique properties, such as once-weekly DPP4 inhibitors or oral insulin. They also include drugs with new mechanisms of action, the focus of this review. Most of these compounds are in Phase 1 and 2, with only a small number having made it to Phase 3 at this time. The new drug classes described include PPAR agonists/modulators, glucokinase activators, glucagon receptor antagonists, anti-inflammatory compounds, G-protein coupled receptor agonists, gastrointestinal peptide agonists other than GLP-1, apical sodium-dependent bile acid transporter (ASBT) inhibitors, SGLT1 and dual SGLT1/SGLT2 inhibitors, and 11beta- HSD1 inhibitors.

Phenolic composition and antioxidant activity of Malus domestica leaves

The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts. The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas. The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated. The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides.

Update on developments with SGLT2 inhibitors in the management of type 2 diabetes

The importance of the kidney's role in glucose homeostasis has gained wider understanding in recent years. Consequently, the development of a new pharmacological class of anti-diabetes agents targeting the kidney has provided new treatment options for the management of type 2 diabetes mellitus (T2DM). Sodium glucose co-transporter type 2 (SGLT2) inhibitors, such as dapagliflozin, canagliflozin, and empagliflozin, decrease renal glucose reabsorption, which results in enhanced urinary glucose excretion and subsequent reductions in plasma glucose and glycosylated hemoglobin concentrations. Modest reductions in body weight and blood pressure have also been observed following treatment with SGLT2 inhibitors. SGLT2 inhibitors appear to be generally well tolerated, and have been used safely when given as monotherapy or in combination with other oral anti-diabetes agents and insulin. The risk of hypoglycemia is low with SGLT2 inhibitors. Typical adverse events appear to be related to the presence of glucose in the urine, namely genital mycotic infection and lower urinary tract infection, and are more often observed in women than in men. Data from long-term safety studies with SGLT2 inhibitors and from head-to-head SGLT2 inhibitor comparator studies are needed to fully determine their benefit-risk profile, and to identify any differences between individual agents. However, given current safety and efficacy data, SGLT2 inhibitors may present an attractive option for T2DM patients who are failing with metformin monotherapy, especially if weight is part of the underlying treatment consideration.

Combinational therapy with metformin and sodium-glucose cotransporter inhibitors in management of type 2 diabetes: systematic review and meta-analyses

AIMS

In search of add-on treatments to metformin, sodium-glucose cotransporter-2 (SGLT-2) inhibitors are potential candidates. This meta-analysis examines the potential use of SGLT-2 inhibitors in combination with metformin as a therapeutic option for type 2 diabetes management in patients with inadequate control with metformin.

METHODS

A literature search was made in several databases for randomized controlled trials (RCTs) utilizing metformin therapy combined with SGLT-2 inhibitors or placebo. Heterogeneity was estimated with I(2) statistics and random effect model was chosen for the meta-analyses of mean differences in changes from baseline in both SGLT-2 inhibitor treated and control groups.

RESULTS

Seven RCTs were selected for the meta-analysis. In comparison with placebo-MET, the SGLT-2 inhibitor-MET combination therapy resulted in significant HbA1c decline in 12-24 week duration, to less extent after 1 year (-0.37 [-0.77, 0.03]; P=0.07) but not by 2 year (-0.41 [-1.09, 0.28]; P=0.24) duration. SGLT-2 inhibitor-MET significantly lowered FPG and body weight after 24 weeks, 1 year, and 2 years. Systolic and diastolic blood pressure declined only in the short-term (12-24 weeks). After 2 years, neither systolic (-1.80 [-6.18, 2.58]; P=0.42) nor diastolic blood pressure (-0.20 [-2.94, 2.54]; P=0.89) declined significantly more than control. Incidence of suspected genital infections was slightly more in SGLT-2 inhibitor-MET group.

CONCLUSION

SGLT-2 inhibition in combination with metformin is a potential therapeutic option based on its effects on glycemic control, body weight, and blood pressure, but further trials are required to refine this evidence.

SGLT2 inhibitors to control glycemia in type 2 diabetes mellitus: a new approach to an old problem

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of antidiabetic agents with a novel insulin-independent mechanism of action. The SGLT2 is a transporter found in the proximal tubule of the kidney and is responsible for approximately 90% of renal glucose reabsorption. The SGLT2 inhibitors reduce reabsorption of glucose in the kidney, resulting in glucose excretion in the urine (50-90 g of ~180 g filtered by the kidneys daily), which in turn lowers plasma glucose levels in people with diabetes. The insulin-independent mechanism of action of SGLT2 inhibitors dictates that they are associated with a very low risk of hypoglycemia and can be used in patients with any degree of β-cell function or insulin sensitivity. Clinical trials have shown that SGLT2 inhibitors are effective at reducing blood glucose levels, body weight, and blood pressure when used as monotherapy or in combination with other antidiabetic agents in patients with type 2 diabetes mellitus. Treatment with SGLT2 inhibitors is generally well tolerated, although these agents have been associated with an increased incidence of genital infections. The SGLT2 inhibitors have become a valuable addition to the armory of drugs used to treat patients with type 2 diabetes mellitus, and several agents within the class are currently under investigation in phase III clinical trials.

Metabolism and excretion of canagliflozin in mice, rats, dogs, and humans

Canagliflozin is an oral antihyperglycemic agent used for the treatment of type 2 diabetes mellitus. It blocks the reabsorption of glucose in the proximal renal tubule by inhibiting the sodium-glucose cotransporter 2. This article describes the in vivo biotransformation and disposition of canagliflozin after a single oral dose of [(14)C]canagliflozin to intact and bile duct-cannulated (BDC) mice and rats and to intact dogs and humans. Fecal excretion was the primary route of elimination of drug-derived radioactivity in both animals and humans. In BDC mice and rats, most radioactivity was excreted in bile. The extent of radioactivity excreted in urine as a percentage of the administered [(14)C]canagliflozin dose was 1.2%-7.6% in animals and approximately 33% in humans. The primary pathways contributing to the metabolic clearance of canagliflozin were oxidation in animals and direct glucuronidation of canagliflozin in humans. Unchanged canagliflozin was the major component in systemic circulation in all species. In human plasma, two pharmacologically inactive O-glucuronide conjugates of canagliflozin, M5 and M7, represented 19% and 14% of total drug-related exposure and were considered major human metabolites. Plasma concentrations of M5 and M7 in mice and rats from repeated dose safety studies were lower than those in humans given canagliflozin at the maximum recommended dose of 300 mg. However, biliary metabolite profiling in rodents indicated that mouse and rat livers had significant exposure to M5 and M7. Pharmacologic inactivity and high water solubility of M5 and M7 support glucuronidation of canagliflozin as a safe detoxification pathway.

Sodium Glucose Co-transporter Type 2 (SGLT2) Inhibitors: Targeting the Kidney to Improve Glycemic Control in Diabetes Mellitus

Although hyperglycemia is a key therapeutic focus in the management of patients with type 2 diabetes mellitus (T2DM), many patients experience sub-optimal glycemic control. Current glucose-lowering agents involve the targeting of various body organs. Sodium glucose co-transporter type 2 (SGLT2) inhibitors target the kidney, reduce renal glucose reabsorption, and increase urinary glucose elimination, thus lowering glucose blood levels. This review examines some of the key efficacy and safety data from clinical trials of the main SGLT2 inhibitors approved or currently in development, and provides a rationale for the use of SGLT2 inhibitors in the treatment of T2DM.

Endothelial dysfunction in diabetes: pathogenesis, significance, and treatment

Type 2 diabetes (T2D) markedly increases the risk of cardiovascular disease. Endothelial dysfunction (ED), an early indicator of diabetic vascular disease, is common in T2D and independently predicts cardiovascular risk. Although the precise pathogenic mechanisms for ED in T2D remain unclear, at inception they probably involve uncoupling of both endothelial nitric oxide synthase activity and mitochondrial oxidative phosphorylation, as well as the activation of vascular nicotinamide adenine dinucleotide phosphate oxidase. The major contributing factors include dyslipoproteinemia, oxidative stress, and inflammation. Therapeutic interventions are designed to target these pathophysiological factors that underlie ED. Therapeutic interventions, including lifestyle changes, antiglycemic agents and lipid-regulating therapies, aim to correct hyperglycemia and atherogenic dyslipidemia and to improve ED. However, high residual cardiovascular risk is seen in both research and clinical practice settings. Well-designed studies of endothelial function in appropriately selected volunteers afford a good opportunity to test new therapeutic interventions, paving the way for clinical trials and utilization in the care of the diabetic patient. However, based on the results from a recent clinical trial, niacin should not be added to a statin in individuals with low high-density lipoprotein cholesterol and very well controlled low-density lipoprotein cholesterol.

Active- and placebo-controlled dose-finding study to assess the efficacy, safety, and tolerability of multiple doses of ipragliflozin in patients with type 2 diabetes mellitus

AIM

To evaluate the efficacy, safety, and tolerability of multiple doses of ipragliflozin. This novel selective inhibitor of sodium glucose co-transporter 2 is in clinical development for the treatment of patients with type 2 diabetes mellitus (T2DM).

METHODS

In a 12-week, multicenter, double-blind, randomized, active- and placebo-controlled dose-finding study, patients were randomized to one of four ipragliflozin treatment groups (12.5, 50, 150, and 300 mg once daily), placebo, or active control (metformin). The primary efficacy outcome was the mean change from baseline to Week 12 of glycosylated hemoglobin (HbA1c) compared with placebo.

RESULTS

Ipragliflozin showed a dose-dependent decrease in HbA1c of -0.49% to -0.81% at Week 12 compared with placebo (P<0.001); a decrease of -0.72% was seen with metformin. Among the ipragliflozin groups there was also a dose-dependent reduction in body weight of up to 1.7 kg. Proportions of patients experiencing treatment-emergent adverse events were similar across all groups: ipragliflozin (45.7-58.8%), placebo (62.3%), and metformin (59.4%). No clinically relevant effects were observed for other safety measures.

CONCLUSIONS

After 12 weeks of treatment, ipragliflozin dose-dependently decreased HbA1c, with ipragliflozin ≥50 mg/day in patients with T2DM; an effect comparable to metformin. No safety or tolerability concerns were identified.

Evolving therapeutic options for type 2 diabetes mellitus: an overview

INTRODUCTION

Many oral antidiabetic drugs (OADs) are available for patients with type 2 diabetes mellitus (T2DM). However, it is recognized that additional therapies are needed and several new compounds are in advanced stages of development.

PURPOSE

This narrative review considers the essential features of a successful OAD, the main classes of OADs that are currently used, and the therapies that may be available in the upcoming years.

RESULTS AND CONCLUSIONS

The first OADs (sulfonylureas and biguanides) were discovered by chance. Although effective in reducing blood glucose levels, early sulfonylureas were associated with significant off-target effects, and the biguanide phenformin was discontinued due to adverse events. Although metformin is in the same drug class, it has a better safety profile and is now recommended as first-line treatment, except when contraindicated. Nonetheless, many patients require additional glucose control (even on metformin) with an agent that has a complementary mechanism of action. Developments in bench science have facilitated the selection of agents for specific therapeutic targets, with the thiazolidinediones providing an interesting example. This OAD class initially appeared encouraging, yet in clinical practice was associated with safety concerns. As a result, newer agents, such as dipeptidyl peptidase-4 inhibitors, are undergoing more rigorous safety evaluations than OADs of previous generations. Promising compounds with novel mechanisms of action include the sodium-glucose co-transporter 2 inhibitors, the G-protein-coupled receptor agonists, and the balanced dual peroxisome proliferator-activated receptor-α/γ agonists. There is optimism that in the next few years, novel classes of OADs that are currently under development will offer additional blood glucose control options via complementary mechanisms of action. However, history has shown that compounds of the same class can have different safety profiles and treatment effects. Therefore, high-quality clinical trial evidence is needed for every compound.

A novel SGLT is expressed in the human kidney

Selective inhibitors of sodium-glucose cotransporter 2 (SGLT2)-mediated reabsorption of glucose in the proximal tubule of the kidney are being developed for the treatment of diabetes. SGLT2 shares high degree of homology with SGLT3; however, very little is known about the expression and functional role of SGLT3 in the human kidney. Indeed, the SGLT2 inhibitors that are currently in clinical trials might affect the expression and/or the activity of SGLT3. Therefore, the present study examined the expression of SGLT3 mRNA and protein in human kidney and in a human proximal tubule HK-2 cell line. The results indicated that human SGLT3 (hSGLT3) message and protein are expressed both in vivo and in vitro. We also studied the activity of hSGLT3 protein following its over-expression in mammalian kidney-derived COS-7 cells and in HK-2 cells treated with the imino sugar deoxynojirimycin (DNJ), a potent agonist of hSGLT3. Over-expression of hSGLT3 in COS-7 cells increased intracellular sodium concentration by 3-fold without affecting glucose transport. Activation of hSGLT3 with DNJ (50μM) increased sodium uptake in HK-2 cells by 5.5 fold and this effect could be completely blocked with SGLT inhibitor phlorizin (50μM). These results suggest that SGLT3 is expressed in human proximal tubular cells where it serves as a novel sodium transporter. Up-regulation of the expression of SGLT3 in the proximal tubule in diabetic patients may contribute to the elevated sodium transport in this segment of the nephron that has been postulated to promote hyperfiltration and renal injury.