Why Do SGLT2 inhibitors inhibit only 30-50% of renal glucose reabsorption in humans?

Mechanistic Modeling of Empagliflozin: Predicting Pharmacokinetics, Urinary Glucose Excretion, and Investigating Compensatory Role of SGLT1 in Renal Glucose Reabsorption

The aim of this study was to use a combination of physiologically based pharmacokinetic (PBPK) modeling and urinary glucose excretion (UGE) modeling to predict the time profiles of pharmacokinetics (PK) and UGE for the sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin (EMP). Additionally, the study aims to explore the compensatory effect of SGLT1 in renal glucose reabsorption (RGR) when SGLT2 is inhibited. The PBPK-UGE model was developed using physicochemical and biochemical properties, renal physiological parameters, binding kinetics, glucose, and Na+ reabsorption kinetics by SGLT1/2. For area under the plasma concentration-time curve, maximum plasma concentration, and cumulative EMP excretion in urine, the predicted values fell within a range of 0.5-2.0 when compared to observed data. Additionally, the simulated UGE data also matched well with the clinical data, further validating the accuracy of the model. According to the simulations, SGLT1 and SGLT2 contributed approximately 13% and 87%, respectively, to RGR in the absence of EMP. However, in the presence of EMP at doses of 2.5 and 10 mg, the contribution of SGLT1 to RGR significantly increased to approximately 76%-82% and 89%-93%, respectively, in patients with type 2 diabetes mellitus. Furthermore, the model supported the understanding that the compensatory effect of SGLT1 is the underlying mechanism behind the moderate inhibition observed in total RGR. The PBPK-UGE model has the capability to accurately predict the PK and UGE time profiles in humans. Furthermore, it provides a comprehensive analysis of the specific contributions of SGLT1 and SGLT2 to RGR in the presence or absence of EMP.

A kidney-hypothalamus axis promotes compensatory glucose production in response to glycosuria

The kidneys facilitate energy conservation through reabsorption of nutrients including glucose. Almost all the filtered blood glucose is reabsorbed by the kidneys. Loss of glucose in urine (glycosuria) is offset by an increase in endogenous glucose production to maintain normal energy supply in the body. How the body senses this glucose loss and consequently enhances glucose production is unclear. Using renal Glut2 knockout mice, we demonstrate that elevated glycosuria activates the hypothalamic-pituitary-adrenal axis, which in turn drives endogenous glucose production. This phenotype was attenuated by selective afferent renal denervation, indicating the involvement of the afferent nerves in promoting the compensatory increase in glucose production. In addition, through plasma proteomics analyses we observed that acute phase proteins - which are usually involved in body's defense mechanisms against a threat - were the top candidates which were either upregulated or downregulated in renal Glut2 KO mice. Overall, afferent renal nerves contribute to promoting endogenous glucose production in response to elevated glycosuria and loss of glucose in urine is sensed as a biological threat in mice. These findings may be useful in improving efficiency of drugs like SGLT2 inhibitors that are intended to treat hyperglycemia by enhancing glycosuria but are met with a compensatory increase in endogenous glucose production.

SGLT2 Inhibitors and Kidney Protection: Mechanisms Beyond Tubuloglomerular Feedback

Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce the risk for kidney failure and are a key component of guideline-directed therapy for CKD. While SGLT2 inhibitors' ability to activate tubuloglomerular feedback and reduce hyperfiltration-mediated kidney injury is considered to be the central mechanism for kidney protection, recent data from experimental studies raise questions on the primacy of this mechanism. This review examines SGLT2 inhibitors' role in tubuloglomerular feedback and summarizes emerging evidence on following of SGLT2 inhibitors' other putative mechanisms for kidney protection: optimization of kidney's energy substrate utilization and delivery, regulation of autophagy and maintenance of cellular homeostasis, attenuation of sympathetic hyperactivity, and improvement in vascular health and microvascular function. It is imperative to examine the effect of SGLT2 inhibition on these different physiologic processes to help our understanding of mechanisms underpinning kidney protection with this important class of drugs.

Transcellular Barriers to Glucose Delivery in the Body

Glucose is the universal fuel of most mammalian cells, and it is largely replenished through dietary intake. Glucose availability to tissues is paramount for the maintenance of homeostatic energetics and, hence, supply should match demand by the consuming organs. In its journey through the body, glucose encounters cellular barriers for transit at the levels of the absorbing intestinal epithelial wall, the renal epithelium mediating glucose reabsorption, and the tight capillary endothelia (especially in the brain). Glucose transiting through these cellular barriers must escape degradation to ensure optimal glucose delivery to the bloodstream or tissues. The liver, which stores glycogen and generates glucose de novo, must similarly be able to release it intact to the circulation. We present the most up-to-date knowledge on glucose handling by the gut, liver, brain endothelium, and kidney, and discuss underlying molecular mechanisms and open questions. Diseases associated with defects in glucose delivery and homeostasis are also briefly addressed. We propose that the universal problem of sparing glucose from catabolism in favor of translocation across the barriers posed by epithelia and endothelia is resolved through common mechanisms involving glucose transfer to the endoplasmic reticulum, from where glucose exits the cells via unconventional cellular mechanisms.

Insulin and the kidneys: a contemporary view on the molecular basis

Insulin is a hormone that is composed of 51 amino acids and structurally organized as a hexamer comprising three heterodimers. Insulin is the central hormone involved in the control of glucose and lipid metabolism, aiding in processes such as body homeostasis and cell growth. Insulin is synthesized as a large preprohormone and has a leader sequence or signal peptide that appears to be responsible for transport to the endoplasmic reticulum membranes. The interaction of insulin with the kidneys is a dynamic and multicenter process, as it acts in multiple sites throughout the nephron. Insulin acts on a range of tissues, from the glomerulus to the renal tubule, by modulating different functions such as glomerular filtration, gluconeogenesis, natriuresis, glucose uptake, regulation of ion transport, and the prevention of apoptosis. On the other hand, there is sufficient evidence showing the insulin receptor's involvement in renal functions and its responsibility for the regulation of glucose homeostasis, which enables us to understand its contribution to the insulin resistance phenomenon and its association with the progression of diabetic kidney disease.

Bibliometric and visualized analysis of sodium-Glucose cotransporter 2 inhibitors

Background: Sodium-glucose cotransporter 2 inhibitors have proved to be extremely effective and reliable in reducing hyperglycemia, and have also been used for the treatment of cardiovascular and renal disease in patients with or without type 2 diabetes. Thousands of research articles on SGLT2 inhibitors have been published in the past, but few bibliometric analyses have systematically been studied this field. We aimed to visualize the global research hotspots and trends of SGLT2 inhibitors using a bibliometric analysis to provide new evidence and ideas for researchers and clinicians in this field. Methods: We retrieved publications from Science Citation Index Expanded of Web of Science Core Collection in 2004-2022 on 1 July 2022. Microsoft Excel, CiteSpace and VOSviewer were employed to collect publication data, analyze publication trends, and visualize relevant results. Results: We identified 4,419 original research articles on SGLT2 inhibitors published between 2004 and the first half of 2022. Global SGLT2 inhibitors-related research increased rapidly from 2004 to 2022, especially recently. United States made the greatest contribution to the topic, with (1,629, 36.86%) publications and citations (88,892). AstraZeneca was the most prolific institutions (272, 6.16%). Heerspink HJL published the most related articles (98), whereas Zinman B was cited the most frequently (1,784 citations). Diabetes Obesity and Metabolism was the journal with the most studies (406, 9.19%), and The New England Journal of Medicine was the most commonly cited journal (11,617 citations), with nine of the top 10 co-cited references published in this journal. The emerging keywords "heart failure," "diabetic cardiomyopathy," "ejection fraction," "mortality," "biomarker," "fibrosis," "ampk," and "guideline" appeared the most recently as research frontiers. Conclusion: United States is the leader in SGLT2 inhibitor research. Recently, the research on SGLT2 inhibitors has focused on clinical trials, related mechanisms, and therapy. In the future, the research on SGLT2 inhibitors will delve into molecular mechanisms, especially those related to fibrosis and AMPK, revealing the link between SGLT2 inhibitors and heart failure and diabetic cardiomyopathy will be the next research hotspot.

Using a Mathematical Modeling To Simulate Pharmacokinetics and Urinary Glucose Excretion of Luseogliflozin and Explore the Role of SGLT1/2 in Renal Glucose Reabsorption

(1) Purpose: To develop a mathematical model combining physiologically based pharmacokinetic and urinary glucose excretion (PBPK-UGE) to simultaneously predict pharmacokinetic (PK) and UGE changes of luseogliflozin (LUS) as well as to explore the role of sodium-glucose cotransporters (SGLT1 and SGLT2) in renal glucose reabsorption (RGR) in humans. (2) Methods: The PBPK-UGE model was built using physicochemical and biochemical properties, binding kinetics data, affinity to SGLTs for glucose, and physiological parameters of renal tubules. (3) Results: The simulations using this model clarified that SGLT1/2 contributed 15 and 85%, respectively, to RGR in the absence of LUS. However, in the presence of LUS, the contribution proportion of SGLT1 rose to 52-76% in healthy individuals and 55-83% in T2DM patients, and that of SGLT2 reduced to 24-48 and 17-45%, respectively. Furthermore, this model supported the underlying mechanism that only 23-40% inhibition of the total RGR with 5 mg of LUS is resulted from SGLT1's compensatory effect and the reabsorption activity of unbound SGLT2. (4) Conclusion: This PBPK-UGE model can predict PK and UGE in healthy individuals and T2DM patients and can also analyze the contribution of SGLT1/2 to RGR with and without LUS.

Treatment of HFpEF beyond the SGLT2-Is: Does the Addition of GLP-1 RA Improve Cardiometabolic Risk and Outcomes in Diabetic Patients?

Heart failure with preserved ejection fraction (HFpEF) is a common clinical syndrome frequently seen in elderly patients, the incidence of which is steadily increasing due to an ageing population and the increasing incidence of diseases, such as diabetes, hypertension, obesity, chronic renal failure, and so on. It is a multifactorial disease with different phenotypic aspects that share left ventricular diastolic dysfunction, and is the cause of about 50% of hospitalizations for heart failure in the Western world. Due to the complexity of the disease, no specific therapies have been identified for a long time. Sodium-Glucose Co-Transporter 2 Inhibitors (SGLT2-Is) and Glucagon-Like Peptide Receptor Agonists (GLP-1 RAs) are antidiabetic drugs that have been shown to positively affect heart and kidney diseases. For SGLT2-Is, there are precise data on their potential benefits in heart failure with reduced ejection fraction (HFrEF) as well as in HFpEF; however, insufficient evidence is available for GLP-1 RAs. This review addresses the current knowledge on the cardiac effects and potential benefits of combined therapy with SGLT2-Is and GLP-1RAs in patients with HFpEF.

SGLT2 Inhibitors in Acute Heart Failure: A Meta-Analysis of Randomized Controlled Trials

Acute heart failure (AHF) is a major public health concern, affecting 26 million worldwide. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a class of glucose-lowering drugs, comprising canagliflozin, dapagliflozin, and empagliflozin that are being explored for AHF. We aim to meta-analyze the effectiveness of SGLT2 inhibitors compared to placebo for primary outcomes including all-cause and cardiovascular mortality, heart failure events, symptomatic improvement, and readmissions. Our secondary outcome is the risk of serious adverse events. This meta-analysis has been designed in accordance with the PRISMA Statement 2020. A systematic search across PubMed, Scopus, and Cochrane Library was conducted through August 13, 2022. The following keywords were utilized: sglt2, sodium-glucose transporter 2 inhibitors, sglt2 inhibitors, decompensated heart failure, de-novo heart failure, and/or acute heart failure. Only randomized controlled trials (RCTs) with adult patients (>18 years), hospitalized with de-novo AHF, acutely decompensated chronic heart failure with reduced, borderline, or preserved ejection, and receiving SGLT2 inhibitors were included. A quantitative analytical methodology was applied where the standardized mean difference (SMD) applying 95% confidence intervals (CI) for continuous outcomes and risk ratio (RR) with 95% CI was yielded. All tests were carried out on Review Manager 5.4 (Cochrane). In total, three RCTs were included pooling in a total of 1831 patients where 49.9% received SGLT2 inhibitors. The mean age was 72.9 years in the interventional group compared to 70.6 years in the placebo. Only 33.7% of the sample was female. The follow-up spanned 2−9 months. Heart failure events were reduced by 62% in the interventional group (RR = 0.66, p < 0.0001). readmissions had a reduced risk of 24% with SGLT2 inhibitors (RR = 0.76, p = 0.03). We assessed the efficacy and safety of SGLT2 inhibitors in preventing complications post-AHF. The odds of all-cause mortality, cardiovascular mortality, heart failure events, and re-admissions rates were substantially reduced within the first 1−9 months of hospitalization.

Changes in Serum Creatinine May Cause Hypoglycemia among Non-Critically Ill Patients Admitted to Internal Medicine Units

Background: The association between changes in serum creatinine levels and hypoglycemia during hospitalization was investigated. Methods: This was a retrospective analysis of medical charts. Patients were categorized as having significant change in creatinine (SCIC) when serum creatinine levels rose or dropped ≥ 0.3 mg/dL from admission values at any time during their hospitalization. Patients were considered hypoglycemic if they had at least one documented glucose level ≤ 70 mg/dL during the hospitalization. Multiple logistic, linear and Cox regression analyses were used to ascertain the association between incident SCIC, severity and timing with incident hypoglycemia. Results: Included were 25,400 (mean age 69.9 ± 18.0, 49.3% were males). The rate of SCIC was 22.2%, and 62.2% of them were diagnosed upon admission. Patients with SCIC had a higher incidence of hypoglycemia compared to patients without (13.1% vs. 4.1%, respectively, p < 0.001). Patients with SCIC had an increased risk of hypoglycemia (OR 1.853, 95% CI 1.586−2.166, p < 0.001). The magnitude of SCIC was associated with the incidence (OR 1.316, 95% CI 1.197−1.447, p < 0.001) and the number of events (HR 0.054, 95% CI 0.021−0.087, p = 0.001). More than 60% of patients with hypoglycemia had their first event documented during days 0−6 after SCIC occurrence. Of those, the majority of events occurred on day 0−1, and the rate showed a gradual decrease throughout the first 5 days from SCIC occurrence. The results were similar for patients with and without DM. Conclusions: Changes in creatinine during hospitalization may cause hypoglycemia among patients admitted to internal medicine departments, regardless of DM status.

Biomolecular Mechanisms of Cardiorenal Protection with Sodium-Glucose Co-Transporter 2 Inhibitors

Diabetes mellitus (DM) is a metabolic disorder characterized by chronic hyperglycemia and associated with an increased risk of morbidity and mortality, primarily from cardiovascular and renal diseases. Sodium-glucose cotransporter 2 inhibitors (SGLT2-Is) are novel drugs for the treatment of type 2 DM and heart failure (HF). SGLT2-Is mediate protective effects on both the renal and cardiovascular systems. This review addresses the current knowledge on the biomolecular mechanisms of the cardiorenal protective effects of SGLT2-Is, which appear to act mainly through non-glucose-mediated pathways. Cardiorenal protection mechanisms lead to reduced chronic renal disease progression and improved myocardial and coronary endothelial function. Concomitantly, it is possible to observe reflected changes in biomarkers linked with diabetic kidney disease and HF.

In Vitro Alpha-Glucosidase and Alpha-Amylase Inhibitory Activities and Antioxidant Capacity of Helichrysum cymosum and Helichrysum pandurifolium Schrank Constituents

Diabetes mellitus (DM) is a group of systemic metabolic disorders with a high rate of morbidity and mortality worldwide. Due to the detrimental side effects of the current treatment, there is a great need to develop more effective antidiabetic drugs with fewer side effects. Natural products are a well-known source for the discovery of new scaffolds for drug discovery, including new antidiabetic drugs. The genus Helichrysum has been shown to produce antidiabetic natural products. In this investigation, the methanolic extract of H. cymosum and H. pandurifolium resulted in the isolation and identification of eleven known compounds viz 5,8-dihydroxy-7-methoxy-2-phenyl flavanone (1), pinostrobin (2), dihydrobaicalein (3), glabranin (4), allopatuletin (5), pinostrobin chalcone (6), helichrysetin (7), 5-hydroxy-3,7-dimethoxyflavone (8), 3,5-dihydroxy-6,7,8-trimethoxyflavone (9), 3-O-methylquercetin (10), and 3-methylethergalangin (11). The in vitro bio-evaluation of isolated compounds against alpha-glucosidase showed that 10, 5, and 11 demonstrated the highest alpha-glucosidase inhibitory activity with IC50 values of 9.24 ± 0.4, 12.94 ± 0.2, and 16.00 ± 2.4 μM respectively, followed by 7 and 3 with IC50 values of 18.16 ± 1.2 and 44.44 ± 0.2 μM respectively. However, none of these compounds showed a measurable inhibitory effect on alpha-amylase under the experimental conditions used except compound 10 which showed a poor alpha-amylase inhibitory activity with an IC50 value of 230.66 ± 15.8 μM. Additionally, strong total antioxidant capacities were demonstrated by 10, 5 and 7 in ferric-ion reducing antioxidant power assay (374.34 ± 69.7; 334.37 ± 1.7; 279.93 ± 0.8) µmol AAE/mmol. This is the first scientific report to be carried out on alpha-glucosidase inhibitory activities and antioxidant capacities of H. cymosum constituents and a first report on the isolation and identification of methoxyflavanoids from H. pandurifolium. Our findings suggest that these compounds are promising candidates to inhibit alpha-glucosidase as well as oxidative stress related to diabetes. Results from molecular docking provided insight into the observed in vitro alpha-glucosidase inhibitory activities for 5, 7, 10, and 11. It is envisaged that the isolated phytochemicals from these plants may contribute to the development of hypoglycemic lead compounds with anti-diabetic potential.

Loss of function of renal Glut2 reverses hyperglycaemia and normalises body weight in mouse models of diabetes and obesity

AIMS/HYPOTHESIS

Renal GLUT2 is increased in diabetes, thereby enhancing glucose reabsorption and worsening hyperglycaemia. Here, we determined whether loss of Glut2 (also known as Slc2a2) specifically in the kidneys would reverse hyperglycaemia and normalise body weight in mouse models of diabetes and obesity.

METHODS

We used the tamoxifen-inducible CreERT2-Lox system in mice to knockout Glut2 specifically in the kidneys (Ks-Glut2 KO) to establish the contribution of renal GLUT2 to systemic glucose homeostasis in health and in insulin-dependent as well as non-insulin-dependent diabetes. We measured circulating glucose and insulin levels in response to OGTT or IVGTT under different experimental conditions in the Ks-Glut2 KO and their control mice. Moreover, we quantified urine glucose levels to explain the phenotype of the mice independently of insulin actions. We also used a transcription factor array to identify mechanisms underlying the crosstalk between renal GLUT2 and sodium-glucose cotransporter 2 (SGLT2).

RESULTS

The Ks-Glut2 KO mice exhibited improved glucose tolerance and massive glucosuria. Interestingly, this improvement in blood glucose control was eliminated when we knocked out Glut2 in the liver in addition to the kidneys, suggesting that the improvement is attributable to the lack of renal GLUT2. Remarkably, induction of renal Glut2 deficiency reversed hyperglycaemia and normalised body weight in mouse models of diabetes and obesity. Longitudinal monitoring of renal glucose transporters revealed that Sglt2 (also known as Slc5a2) expression was almost abolished 3 weeks after inducing renal Glut2 deficiency. To identify a molecular basis for this crosstalk, we screened for renal transcription factors that were downregulated in the Ks-Glut2 KO mice. Hnf1α (also known as Hnf1a) was among the genes most downregulated and its recovery restored Sglt2 expression in primary renal proximal tubular cells isolated from the Ks-Glut2 KO mice.

CONCLUSIONS/INTERPRETATION

Altogether, these results demonstrate a novel crosstalk between renal GLUT2 and SGLT2 in regulating systemic glucose homeostasis via glucose reabsorption. Our findings also indicate that inhibiting renal GLUT2 is a potential therapy for diabetes and obesity.

Effects of Sodium-Glucose Cotransporter 2 Inhibitors on Water and Sodium Metabolism

Sodium-glucose cotransporter 2 (SGLT2) inhibitors exert hypoglycemic and diuretic effects by inhibiting the absorption of sodium and glucose from the proximal tubule. Currently available data indicate that SGLT2 inhibitors transiently enhance urinary sodium excretion and urinary volume. When combined with loop diuretics, SGLT2 inhibitors exert a synergistic natriuretic effect. The favorable diuretic profile of SGLT2 inhibitors may confer benefits to volume management in patients with heart failure but this natriuretic effect may not be the dominant mechanism for the superior long-term outcomes observed with these agents in patients with heart failure. The first part of this review explores the causes of transient natriuresis and the diuretic mechanisms of SGLT2 inhibitors. The second part provides an overview of the synergistic effects of combining SGLT2 inhibitors with loop diuretics, and the third part summarizes the mechanisms of cardiovascular protection associated with the diuretic effects of SGLT2 inhibitors.

Glucose Metabolism in Acute Kidney Injury and Kidney Repair

The kidneys play an indispensable role in glucose homeostasis via glucose reabsorption, production, and utilization. Conversely, aberrant glucose metabolism is involved in the onset, progression, and prognosis of kidney diseases, including acute kidney injury (AKI). In this review, we describe the regulation of glucose homeostasis and related molecular factors in kidneys under normal physiological conditions. Furthermore, we summarize recent investigations about the relationship between glucose metabolism and different types of AKI. We also analyze the involvement of glucose metabolism in kidney repair after injury, including renal fibrosis. Further research on glucose metabolism in kidney injury and repair may lead to the identification of novel therapeutic targets for the prevention and treatment of kidney diseases.

Human Glucose Transporters in Renal Glucose Homeostasis

The kidney plays an important role in glucose homeostasis by releasing glucose into the blood stream to prevent hypoglycemia. It is also responsible for the filtration and subsequent reabsorption or excretion of glucose. As glucose is hydrophilic and soluble in water, it is unable to pass through the lipid bilayer on its own; therefore, transport takes place using carrier proteins localized to the plasma membrane. Both sodium-independent glucose transporters (GLUT proteins) and sodium-dependent glucose transporters (SGLT proteins) are expressed in kidney tissue, and mutations of the genes coding for these glucose transporters lead to renal disorders and diseases, including renal cancers. In addition, several diseases may disturb the expression and/or function of renal glucose transporters. The aim of this review is to describe the role of the kidney in glucose homeostasis and the contribution of glucose transporters in renal physiology and renal diseases.

SGLT2 Inhibition for Cardiovascular Diseases, Chronic Kidney Disease, and NAFLD

Sodium glucose cotransporter 2 (SGLT-2) inhibitors are the latest class of antidiabetic medications. They prevent glucose reabsorption in the proximal convoluted tubule to decrease blood sugar. Several animal studies revealed that SGLT-2 is profoundly involved in the inflammatory response, fibrogenesis, and regulation of numerous intracellular signaling pathways. Likewise, SGLT-2 inhibitors markedly attenuated inflammation and fibrogenesis and improved the function of damaged organ in animal studies, observational studies, and clinical trials. SGLT-2 inhibitors can decrease blood pressure and ameliorate hypertriglyceridemia and obesity. Likewise, they improve the outcome of cardiovascular diseases such as heart failure, arrhythmias, and ischemic heart disease. SGLT-2 inhibitors are associated with lower cardiovascular and all-cause mortality as well. Meanwhile, they protect against nonalcoholic fatty liver disease (NAFLD), chronic kidney disease, acute kidney injury, and improve micro- and macroalbuminuria. SGLT-2 inhibitors can reprogram numerous signaling pathways to improve NAFLD, cardiovascular diseases, and renal diseases. For instance, they enhance lipolysis, ketogenesis, mitochondrial biogenesis, and autophagy while they attenuate the renin-angiotensin-aldosterone system, lipogenesis, endoplasmic reticulum stress, oxidative stress, apoptosis, and fibrogenesis. This review explains the beneficial effects of SGLT-2 inhibitors on NAFLD and cardiovascular and renal diseases and dissects the underlying molecular mechanisms in detail. This narrative review explains the beneficial effects of SGLT-2 inhibitors on NAFLD and cardiovascular and renal diseases using the results of latest observational studies, clinical trials, and meta-analyses. Thereafter, it dissects the underlying molecular mechanisms involved in the clinical effects of SGLT-2 inhibitors on these diseases.

Prolonged ketosis and glycosuria secondary to SGLT2 inhibitor therapy

Clinicians should be aware of the potential for the pharmacologic activity of SGLT2 inhibitors to persist long after the standard drug clearance period of five half-lives, the typical duration used to guide pre-operative medication recommendations.

Do sodium-glucose co-transporter-2 inhibitors increase plasma glucagon by direct actions on the alpha cell? And does the increase matter for the associated increase in endogenous glucose production?

Sodium-glucose co-transporter-2 inhibitors (SGLT2is) lower blood glucose and are used for treatment of type 2 diabetes. However, SGLT2is have been associated with increases in endogenous glucose production (EGP) by mechanisms that have been proposed to result from SGLT2i-mediated increases in circulating glucagon concentrations, but the relative importance of this effect is debated, and mechanisms possibly coupling SGLT2is to increased plasma glucagon are unclear. A direct effect on alpha-cell activity has been proposed, but data on alpha-cell SGLT2 expression are inconsistent, and studies investigating the direct effects of SGLT2 inhibition on glucagon secretion are conflicting. By contrast, alpha-cell sodium-glucose co-transporter-1 (SGLT1) expression has been found more consistently and appears to be more prominent, pointing to an underappreciated role for this transporter. Nevertheless, the selectivity of most SGLT2is does not support interference with SGLT1 during therapy. Paracrine effects mediated by secretion of glucagonotropic/static molecules from beta and/or delta cells have also been suggested to be involved in SGLT2i-induced increase in plasma glucagon, but studies are few and arrive at different conclusions. It is also possible that the effect on glucagon is secondary to drug-induced increases in urinary glucose excretion and lowering of blood glucose, as shown in experiments with glucose clamping where SGLT2i-associated increases in plasma glucagon are prevented. However, regardless of the mechanisms involved, the current balance of evidence does not support that SGLT2 plays a crucial role for alpha-cell physiology or that SGLT2i-induced glucagon secretion is important for the associated increased EGP, particularly because the increase in EGP occurs before any rise in plasma glucagon.

Recent Advances in the Development of Type 2 Sodium-Glucose Cotransporter Inhibitors for the Treatment of Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) is one of the most serious and prevalent diseases worldwide. In the last decade, type 2 sodium-glucose cotransporter inhibitors (iSGLT2) were approved as alternative drugs for the pharmacological treatment of T2DM. The anti-hyperglycemic mechanism of action of these drugs involves glycosuria. In addition, SGLT2 inhibitors cause beneficial effects such as weight loss, a decrease in blood pressure, and others.

OBJECTIVE

This review aimed to describe the origin of SGLT2 inhibitors and analyze their recent development in preclinical and clinical trials.

RESULTS

In 2013, the FDA approved SGLT2 inhibitors as a new alternative for the treatment of T2DM. These drugs have shown good tolerance with few adverse effects in clinical trials. Additionally, new potential anti-T2DM agents based on iSGLT2 (O-, C-, and N-glucosides) have exhibited a favorable profile in preclinical evaluations, making them candidates for advanced clinical trials.

CONCLUSION

The clinical results of SGLT2 inhibitors show the importance of this drug class as new anti-T2DM agents with a potential dual effect. Additionally, the preclinical results of SGLT2 inhibitors favor the design and development of more selective new agents. However, several adverse effects could be a potential risk for patients.

Profile of Ipragliflozin, an Oral SGLT-2 Inhibitor for the Treatment of Type 2 Diabetes: The Evidence to Date

Background

Sodium-glucose cotransporter-2 (SGLT-2) inhibitors are a novel class of pharmacotherapeutics for type 2 diabetes management that work by reducing renal reabsorption of glucose. Ipragliflozin is a potent, selective SGLT-2 inhibitor used for the management of type 2 diabetes.

Objective

The primary aim of this review is to summarize the available evidence on the efficacy and safety of ipragliflozin for the management of type 2 diabetes. We also review the discovery, pharmacokinetic, and pharmacodynamic profile of ipragliflozin.

Methods

To inform our review, we searched MEDLINE, International Pharmaceutical Abstracts, and Embase to identify relevant papers to ipragliflozin use in type 2 diabetes. Clinical trial registries were also searched.

Results

Findings from randomized clinical trials demonstrate that compared to placebo, ipragliflozin significantly reduces glucose as measured via Hemoglobin A1c and fasting plasma glucose levels. Ipragliflozin is also associated with weight reduction and an improvement in some, but not all, cardiovascular risk markers. Ipragliflozin has a favourable safety profile with a low risk of hypoglycemia and the rates of common adverse events are not significantly different than placebo. Limited data are available to assess rare and long-term adverse effects.

Conclusion

Current evidence shows that ipragliflozin is an effective therapeutic option for the management of glucose control in type 2 diabetes. However, no cardiovascular outcome trials have been conducted to date. Real-world observational studies are still needed to accurately capture any possible rare or long-term adverse events.

Sodium-Glucose Co-transporter-2 Inhibitors and Nephroprotection in Diabetic Patients: More Than a Challenge

Diabetic nephropathy is the most common cause of end-stage renal disease worldwide. Control of blood glucose and blood pressure (BP) reduces the risk of developing this complication, but once diabetic nephropathy is established, it is then only possible to slow its progression. Sodium-glucose cotransporter-2 inhibitors (SGLT2is) are a novel class of oral hypoglycemic agents that increase urinary glucose excretion by suppressing glucose reabsorption at the renal proximal tubule. SGLT2is lower glycated hemoglobin (HbA1c) without increasing the risk of hypoglycemia, induce weight loss and improve various metabolic parameters including BP, lipid profile, albuminuria and uric acid. Several clinical trials have shown that SGLT2is (empagliflozin, dapagliflozin canagliflozin, and ertugliflozin) improve cardiovascular and renal outcomes and mortality in patients with type 2 diabetes. Effects of SGLT2is on the kidney can be explained by multiple pathways. SGLT2is may improve renal oxygenation and intra-renal inflammation thereby slowing the progression of kidney function decline. Additionally, SGLT2is are associated with a reduction in glomerular hyperfiltration, an effect which is mediated by the increase in natriuresis, the re-activation of tubule-glomerular feedback and independent of glycemic control. In this review, we will focus on renal results of major cardiovascular and renal outcome trials and we will describe direct and indirect mechanisms through which SGLT2is confer renal protection.

Intestinal Excretion, Intestinal Recirculation, and Renal Tubule Reabsorption Are Underappreciated Mechanisms That Drive the Distribution and Pharmacokinetic Behavior of Small Molecule Drugs

Drug reabsorption following biliary excretion is well-known as enterohepatic recirculation (EHR). Renal tubular reabsorption (RTR) following renal excretion is also common but not easily assessed. Intestinal excretion (IE) and enteroenteric recirculation (EER) have not been recognized as common disposition mechanisms for metabolically stable and permeable drugs. IE and intestinal reabsorption (IR:EHR/EER), as well as RTR, are governed by dug concentration gradients, passive diffusion, active transport, and metabolism, and together they markedly impact disposition and pharmacokinetics (PK) of small molecule drugs. Disruption of IE, IR, or RTR through applications of active charcoal (AC), transporter knockout (KO), and transporter inhibitors can lead to changes in PK parameters. The impacts of intestinal and renal reabsorption on PK are under-appreciated. Although IE and EER/RTR can be an intrinsic drug property, there is no apparent strategy to optimize compounds based on this property. This review seeks to improve understanding and applications of IE, IR, and RTR mechanisms.

Systematic review and meta-analysis for prevention of cardiovascular complications using GLP-1 receptor agonists and SGLT-2 inhibitors in obese diabetic patients

Patients with type 2 diabetes mellitus (T2DM) and obesity are at high risk of developing cardiovascular disease (CVD). Both glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter (SGLT-2) inhibitors have been shown to prevent CVD in T2DM patients. Additionally, the two drugs reduce body mass. However, it is unknown which drug is more effective at reducing the risk of CVD in such patients. We searched Medline, EMBASE, and Cochrane Library records to February 20, 2021 and performed a network meta-analysis to compare the efficacy with which the drugs reduced the risk of major adverse cardiovascular events (MACE). We included 102,728 patients in 12 studies containing data of obesity subgroup analyses. In T2DM patients with obesity, GLP-1 RAs significantly reduced the risk of MACE versus placebo (relative risk, RR [95% confidence interval, CI]: 0.88 [0.81–0.96]), whereas SGLT-2 inhibitors showed a tendency (RR [95% CI]: 0.91 [0.83–1.00]). In an indirect comparison, GLP-1 RAs were not associated with a significant difference in MACE compared with SGLT-2 inhibitors (RR [95% CI]: 0.97 [0.85–1.09]). Thus, GLP-1 RAs are effective at preventing MACE than placebo in T2DM patients with obesity, although further studies are warranted to conclude their superiority to SGLT-2 inhibitors.

Dapagliflozin reverses the imbalance of T helper 17 and T regulatory cells by inhibiting SGK1 in a mouse model of diabetic kidney disease

An imbalance between T helper 17 (Th17) and T regulatory (Treg) cell subsets contributes to the pathogenesis of diabetic kidney disease (DKD). However, the underlying regulatory mechanisms that cause this imbalance are unknown. Serum/glucocorticoid‐regulated kinase 1 (SGK1) has been suggested to affect Th17 polarization in a salt‐dependent manner, and sodium/glucose cotransporter 2 inhibitors (SGLT2i) have been demonstrated to regulate sodium‐mediated transportation in the renal tubules. This study aimed to evaluate the potential benefits of dapagliflozin (Dap) on DKD, as well as its influence on shifting renal T‐cell polarization and related cytokine secretion. We treated male db/db mice with Dap or voglibose (Vog) and measured blood and kidney levels of Th17 and Treg cells using flow cytometry. We found that Th17 cells were significantly increased, while Treg cells were significantly decreased in diabetic mice. Moreover, Dap suppressed the polarization of Th17/Treg cells by inhibiting SGK1 in diabetic kidneys, and this was accompanied by attenuation of albuminuria and tubulointerstitial fibrosis independent of glycemic control. Taken together, these results demonstrate that the imbalance of Th17/Treg cells plays an important role in the progression of DKD. Moreover, Dap protects against DKD by inhibiting SGK1 and reversing the T‐cell imbalance.

Sodium-Glucose Cotransporter 2 Inhibitors in Patients with Non-Diabetic Chronic Kidney Disease

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors can reduce cardiovascular morbidity and mortality in patients with type 2 diabetes. Furthermore, recent clinical studies have revealed that SGLT2 inhibitors decrease the risk of renal function impairment in patients with type 2 diabetes. However, the effects of SGLT2 inhibitors on non-diabetic chronic kidney disease (CKD) remains unclear. Regarding long-term clinical outcomes, the Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure (DAPA-HF) trial explicitly showed improvements in cardiovascular outcomes in patients presenting with heart failure, even in the absence of diabetes. The reduction in heart failure in patients without diabetes was confirmed following empagliflozin administration in the EMPagliflozin outcomE tRial in patients with chrOnic heart failure with Reduced ejection fraction (EMPEROR-Reduced) trial. A recent systematic review and meta-analysis of DAPA-HF and EMPEROR-Reduced showed improvements in the composite renal endpoint regardless of the presence of diabetes or baseline estimated glomerular filtration rate. The Dapagliflozin and Prevention of Adverse outcomes in Chronic Kidney Disease (DAPA-CKD) trial evaluated patients with CKD with or without type 2 diabetes, irrespective of whether SGLT2 inhibitor dapagliflozin was added for renin-angiotensin system blockade as background renoprotective therapy. In this trial, dapagliflozin reduced the hazard ratio for a composite renal and cardiovascular death endpoint in patients with CKD attributed to various causes, with or without type 2 diabetes.

Cardiovascular benefits of sodium-glucose cotransporter 2 inhibitors in diabetic and nondiabetic patients

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) were developed as antidiabetic agents, but accumulating evidence has shown their beneficial effects on the cardiovascular system. Analyses of the EMPA-REG OUTCOME trial (Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients) suggested that these benefits are independent of glycemic control. Several large-scale outcome trials of SGLT2i also showed cardiovascular benefits in nondiabetic patients, strengthening this perspective. Extensive animal and clinical studies have likewise shown that mechanisms other than the antihyperglycemic effect underlie the cardiovascular benefits. Recent clinical guidelines recommend the use of SGLT2i in patients with type 2 diabetes mellitus and cardiovascular diseases because of the proven cardiovascular protective effects. Since the cardiovascular benefits are independent of glycemic control, the therapeutic spectrum of SGLT2i will likely be extended to nondiabetic patients.

Association of antidiabetic therapies with lower extremity amputation, mortality and healthcare cost from a nationwide retrospective cohort study in Taiwan

We compared risks of clinical outcomes, mortality and healthcare costs among new users of different classes of anti-diabetic medications. This is a population-based, retrospective, new-user design cohort study using the Taiwan National Health Insurance Database between May 2, 2015 and September 30, 2017. An individual was assigned to a medication group based on the first anti-diabetic prescription on or after May 1, 2016: SGLT-2 inhibitors, DPP-4 inhibitors, GLP-1 agonists or older agents (metformin, etc.). Clinical outcomes included lower extremity amputation, peripheral vascular disease, critical limb ischemia, osteomyelitis, and ulcer. We built three Cox proportional hazards models for clinical outcomes and mortality, and three regression models with a log-link function and gamma distribution for healthcare costs, all with propensity-score weighting and covariates. We identified 1,222,436 eligible individuals. After adjustment, new users of SGLT-2 inhibitors were associated with 73% lower mortality compared to those of DPP-4 inhibitors or users of older agents, while 36% lower total costs against those of GLP-1 agonists. However, there was no statistically significant difference in the risk of lower extremity amputation across medication groups. Our study suggested that SGLT-2 inhibitors is associated with lower mortality compared to DPP 4 inhibitors and lower costs compared to GLP-1 agonists.

Effect of sodium-glucose cotransporter-2 inhibitors on aldosterone-to-renin ratio in diabetic patients with hypertension: a retrospective observational study

BACKGROUND

Plasma aldosterone-to-renin ratio (ARR) is popularly used for screening primary aldosteronism (PA). Some medications, including diuretics, are known to have an effect on ARR and cause false-negative and false-positive results in PA screening. Currently, there are no studies on the effects of sodium-glucose cotransporter-2 (SGLT2) inhibitors, which are known to have diuretic effects, on ARR. We aimed to investigate the effects of SGLT2 inhibitors on ARR.

METHODS

We employed a retrospective design; the study was conducted from April 2016 to December 2018 and carried out in three hospitals. Forty patients with diabetes and hypertension were administered SGLT2 inhibitors. ARR was evaluated before 2 to 6 months after the administration of SGLT2 inhibitors to determine their effects on ARR.

RESULTS

No significant changes in the levels of ARR (90.9 ± 51.6 vs. 81.4 ± 62.9) were found. Body mass index, diastolic blood pressure, heart rate, fasting plasma glucose, and hemoglobin A1c were significantly decreased by SGLT2 inhibitors. Serum creatinine was significantly increased.

CONCLUSION

SGLT2 inhibitor administration yielded minimal effects on ARR and did not increase false-negative results in PA screening in patients with diabetes and hypertension more than 2 months after administration.

Prolonged Glucosuria With Sodium-Glucose Cotransporter-2 (SGLT2) Inhibitors: A Case Report and Review of Literature

Sodium-glucose cotransporter-2 (SGLT2) inhibitors assert their role as an anti-diabetic medication by reversibly inhibiting sodium-glucose cotransporters in the renal proximal tubules and resulting in enhanced glucose excretion. Due to their reversible effect on the transporters in the proximal tubule, it is expected that all their metabolic effects, including glucose excretion, should also cease in two to three days, as per their half-life of 10-15 hours. However, it is increasingly being observed that the glycosuric effect of SGLT2 inhibitors persists beyond this duration and, in many cases, exceeds their other known metabolic effects, which resolve sooner. We present a case report of a 53-year-old diabetic male who developed SGLT2 inhibitor-related euglycemic diabetic ketoacidosis (EuDKA) two days after being discharged post a laparoscopic appendectomy procedure. The patient was treated as per the recommended protocols, after which ongoing metabolic acidosis abated, but the patient’s urinary glucose remained on the higher end. We present an up-to-date review of existing evidence on this rare but serious side effect of SGLT2 inhibitors.

Glucose Metabolism in the Kidney: Neurohormonal Activation and Heart Failure Development

The liver is not the exclusive site of glucose production in humans in the postabsorptive state. Robust data support that the kidney is capable of gluconeogenesis and studies have demonstrated that renal glucose production can increase systemic glucose production. The kidney has a role in maintaining glucose body balance, not only as an organ for gluconeogenesis but by using glucose as a metabolic substrate. The kidneys reabsorb filtered glucose through the sodium‐glucose cotransporters sodium‐glucose cotransporter (SGLT) 1 and SGLT2, which are localized on the brush border membrane of the early proximal tubule with immune detection of their expression in the tubularized Bowman capsule. In patients with diabetes mellitus, the renal maximum glucose reabsorptive capacity, and the threshold for glucose passage into the urine, are higher and contribute to the hyperglycemic state. The administration of SGLT2 inhibitors to patients with diabetes mellitus enhances sodium and glucose excretion, leading to a reduction of the glycosuria threshold and tubular maximal transport of glucose. The net effects of SGLT2 inhibition are to drive a reduction in plasma glucose levels, improving insulin secretion and sensitivity. The benefit of SGLT2 inhibitors goes beyond glycemic control, since inhibition of renal glucose reabsorption affects blood pressure and improves the hemodynamic profile and the tubule glomerular feedback. This action acts to rebalance the dense macula response by restoring adenosine production and restraining renin‐angiotensin‐aldosterone activation. By improving renal and cardiovascular function, we explain the impressive reduction in adverse outcomes associated with heart failure supporting the current clinical perspective.

Neural tone and cardio-renal outcomes in patients with type 2 diabetes mellitus: a review of the literature with a focus on SGLT2 inhibitors

Recent clinical trials involving the systemic effects of sodium-glucose cotransporter 2 inhibitors (SGLT2i) have revealed beneficial outcomes pertaining to the microvascular sequelae of type 2 diabetes mellitus (T2DM) such as nephropathy, as well as macrovascular effects such as major adverse cardiovascular effects (MACE). Such findings have spurred the elevation of these agents to level A-tiers of recommendation within clinical guidelines addressing the management of complicated T2DM. While the mechanisms of SGLTi (-flozin drugs) are still being elucidated, a paucity of data exists within the literature appraising the role of neuromodulation and associated mechanisms in the aforementioned outcome studies. Given the role of the nervous system in orchestrating the pathologic processes that hamper cardio-renal status, insight into this topic offers an expanded perspective on T2DM. In this review we investigate the mechanisms by which SGLTi improve cardio-renal function in T2DM patients with emphases on neural tone and nervous system physiology.

Best practices for safe use of SGLT-2 inhibitors developed from an expert panel Delphi consensus process

PURPOSE

Sodium-glucose cotransporter 2 (SGLT-2) inhibitors have demonstrated glycemic efficacy and cardiovascular and renal benefits in people with type 2 diabetes mellitus (T2DM). However, they are also associated with serious adverse events (AEs), but little consensus exists for clinicians regarding AE management. This study aimed to develop a list of best practices for the safe use and monitoring of SGLT-2 inhibitors in people with T2DM.

METHODS

A 15-member interprofessional panel was surveyed in a four-round Delphi process. Panelists were asked to comment on and rank statements regarding initial prescribing considerations and actions for minimizing and managing eight specific AEs and a broad category for other AEs. In the final round, panelists selected if the statements should be considered a best practice specific to SGLT-2 inhibitors, a best practice for general safe medication use in T2DM, or if the statement should not be considered as a best practice for safe medication use.

RESULTS

Consensus was achieved for 36 best practice statements specific to SGLT-2 inhibitors and 24 statements as general best practices for safe medication use. Fifty-six percent of the best practice statements for SGLT-2 inhibitors related to managing and/or preventing hypotension, urinary tract infections, and genital infections. The general best practices for safe medication use primarily focused on medication histories, past medical history considerations, physical exam components, and patient education.

CONCLUSION

A list of best practice statements was developed using the Delphi method, which can be utilized by clinicians to guide the safe use and monitoring of SGLT-2 inhibitors in people with T2DM.

Real-World Clinical Experience with SGLT2 Inhibitors: Use of Special Screening Tool for Type 2 Diabetes Patients to Avoid Serious Adverse Events: A Single-Centre Prospective Study

<b><i>Background:</i></b> Promising results of clinical trials involving SGLT2 inhibitors urge every clinician managing diabetes to use them. However, upcoming real-world data still show increased incidence of adverse events, but efficacy is comparable to clinical trials. <b><i>Objectives:</i></b> Genitourinary infection is the most commonly reported adverse effect with SGLT2 inhibitors. We evaluated effectiveness of patient screening protocol and advice of hygiene and hydration to avoid adverse effects of SGLT2 inhibitors in real-world setting. <b><i>Method:</i></b> This was a prospective observational longitudinal study which included consecutive subjects with uncontrolled T2DM recommended with SGLT2i after a simple screening protocol from December 2017 to November 2018. The adverse effects and metabolic parameters were evaluated at 1st, 3rd, 6th, and 12th months for each patient. <b><i>Results:</i></b> Of 413 patients recommended for SGLT2 inhibitors, 335 patients started the medication. At baseline, average age, glycosylated haemoglobin (HbA1c), and weight were 53 years, 9.5%, and 82 kg, respectively. Data of 332, 299, 270, and 231 patients were available at the 1st, 3rd, 6th, and 12th months for safety follow-up, respectively. Genitourinary tract infection was the most common adverse effect (8%) followed by ketosis (4%). Two patients needed to stop the drug permanently due to recurrent transient ischaemic attack and emphysematous pyelonephritis. Significant reduction in mean weight and HbA1c was observed at 6 months (<i>n</i> = 270): 2.9 kg and 1.1%, respectively, and at 12 months (<i>n</i> = 231): 3.8 kg and 1.6%, respectively. <b><i>Conclusion:</i></b> Simple screening protocol for patients considered for SGLT2i significantly reduced incidence of genitourinary adverse events.

SGLT2 inhibitors: mechanisms of cardiovascular benefit beyond glycaemic control

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are effective antidiabetic therapies in patients with type 2 diabetes mellitus and are associated with improved glycaemic control as well as with reductions in body mass and blood pressure. In large cardiovascular outcome trials in patients with diabetes, SGLT2 inhibitors improve cardiovascular and renal outcomes, including hospitalization for heart failure, with this benefit extending to patients without diabetes who have heart failure with reduced ejection fraction. The possible mechanisms of benefit are being extensively investigated because they are unlikely to be related to improved glycaemic control. Early natriuresis with a reduction in plasma volume, a consequent rise in haematocrit, improved vascular function, a reduction in blood pressure and changes in tissue sodium handling are all likely to have a role. Additional mechanisms of SGLT2 inhibitors that might be beneficial include a reduction in adipose tissue-mediated inflammation and pro-inflammatory cytokine production, a shift towards ketone bodies as the metabolic substrate for the heart and kidneys, reduced oxidative stress, lowered serum uric acid level, reduced glomerular hyperfiltration and albuminuria, and suppression of advanced glycation end-product signalling. Further outcome trials and mechanistic studies, including in patients with heart failure with preserved ejection fraction or non-diabetic kidney disease, might identify other possible mechanisms of benefit of SGLT2-inhibitor therapy.

Blood pressure control in type 2 diabetes mellitus with arterial hypertension. The important ancillary role of SGLT2-inhibitors and GLP1-receptor agonists

Type 2 diabetes mellitus and arterial hypertension are major cardiovascular risks factors which shares metabolic and haemodynamic abnormalities as well as pathophysiological mechanisms. The simultaneous presence of diabetes and arterial hypertension increases the risk of left ventricular hypertrophy, congestive heart failure, and stroke, as compared to either condition alone. A number of guidelines recommend lifestyle measures such as salt restriction, weight reduction and ideal body weight mainteinance, regular physical activity and smoking cessation, together with moderation of alcohol consumption and high intake of vegetables and fruits, as the basis for reduction of blood pressure and prevention of CV diseases. Despite the availability of multiple drugs effective for hypertension, BP targets are reached in only 50 % of patients, with even fewer individuals with T2DM-achieving goals. It is established that new emerging classes of type 2 diabetes mellitus treatment, SGLT2 inhibitors and GLP1-receptor agonists, are efficacious on glucose control, and safe in reducing HbA1c significantly, without increasing hypoglycemic episodes. Furthermore, in recent years, many CVOT trials have demonstrated, using GLP1-RA or SGLT2-inihibitors compared to placebo (in combination with the usual diabetes medications) important benefits on reducing MACE (cardio-cerebral vascular events) in the diabetic population. In this hypothesis-driven review, we have examined the anti-hypertensive effects of these novel molecules of the two different classes, in the diabetic population, and suggest that they could have an interesting ancillary role in controlling blood pressure in type 2 diabetic patients.

Sodium-glucose cotransporters: Functional properties and pharmaceutical potential

Glucose is the most abundant monosaccharide, and an essential source of energy for most living cells. Glucose transport across the cell membrane is mediated by two types of transporters: facilitative glucose transporters (gene name: solute carrier 2A) and sodium-glucose cotransporters (SGLTs; gene name: solute carrier 5A). Each transporter has its own substrate specificity, distribution, and regulatory mechanisms. Recently, SGLT1 and SGLT2 have attracted much attention as therapeutic targets for various diseases. This review addresses the basal and functional properties of glucose transporters and SGLTs, and describes the pharmaceutical potential of SGLT1 and SGLT2.

Effects of ertugliflozin on renal function over 104 weeks of treatment: a post hoc analysis of two randomised controlled trials

AIMS/HYPOTHESIS

This study aimed to evaluate the effect of ertugliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, on eGFR and albuminuria (urine albumin/creatinine ratio [UACR]) vs glimepiride or placebo/glimepiride (non-ertugliflozin) over 104 weeks of treatment in participants with type 2 diabetes mellitus, using pooled data from two randomised controlled, active comparator studies from the eValuation of ERTugliflozin effIcacy and Safety (VERTIS) programme (Clinicaltrials.gov NCT01999218 [VERTIS SU] and NCT02033889 [VERTIS MET]). In the VERTIS SU study, ertugliflozin was evaluated vs glimepiride over 104 weeks. In the VERTIS MET study, ertugliflozin was evaluated vs placebo over 26 weeks; eligible participants were switched from placebo to blinded glimepiride from week 26 to week 104. The glycaemic efficacy of ertugliflozin vs non-ertugliflozin was also assessed in the pooled population.

METHODS

Post hoc, exploratory analysis was used to investigate mean changes from baseline in eGFR and UACR over 104 weeks.

RESULTS

Overall, mean (SD) baseline eGFR was 88.2 (18.8) ml min^-1 (1.73 m)^-2 and geometric mean (95% CI) of baseline UACR was 1.31 mg/mmol (1.23, 1.38). At week 6, the changes in eGFR from baseline were -2.3, -2.7 and -0.7 ml min^-1 (1.73 m)^-2 for the ertugliflozin 5 mg, ertugliflozin 15 mg and non-ertugliflozin groups, respectively. Mean eGFR in the ertugliflozin groups increased over time thereafter, while it decreased in the non-ertugliflozin group. Week 104 changes in eGFR from baseline were -0.2, 0.1 and -2.0 ml min^-1 (1.73 m)^-2 for the ertugliflozin 5 mg, ertugliflozin 15 mg and non-ertugliflozin groups, respectively. Among 415 patients (21.4% of the cohort) with albuminuria at baseline, the ertugliflozin groups had greater reductions in UACR at all measured time points up to week 104. At week 104, the non-ertugliflozin-corrected difference in UACR (95% CI) was -29.5% (-44.8, -9.8; p < 0.01) for ertugliflozin 5 mg and -37.6% (-51.8, -19.2; p < 0.001) for ertugliflozin 15 mg. Least squares mean changes from baseline in HbA_1c (mmol/mol [95% CI]) at week 104 were similar between treatment groups: -6.84 (-7.64, -6.03), -7.74 (-8.54, -6.94) and -6.84 (-7.65, -6.03) in the ertugliflozin 5 mg, ertugliflozin 15 mg and non-ertugliflozin groups, respectively. Least squares mean changes from baseline in HbA1_c (% [95% CI]) at week 104 were: -0.63 (-0.70, -0.55), -0.71 (-0.78, -0.64) and -0.63 (-0.70, -0.55) in the ertugliflozin 5 mg, ertugliflozin 15 mg and non-ertugliflozin groups, respectively.

CONCLUSIONS/INTERPRETATION

Ertugliflozin reduced eGFR at week 6, consistent with the known pharmacodynamic effects of SGLT2 inhibitors on renal function. Over 104 weeks, eGFR values returned to baseline and were higher with ertugliflozin compared with non-ertugliflozin treatment, even though changes in HbA_1c did not differ between the groups. Ertugliflozin reduced UACR in patients with baseline albuminuria.

TRIAL REGISTRATION

clinicaltrials.gov NCT01999218 and NCT02033889.

Type 2 Diabetes Mellitus: A Review of Multi-Target Drugs

Diabetes Mellitus (DM) is a multi-factorial chronic health condition that affects a large part of population and according to the World Health Organization (WHO) the number of adults living with diabetes is expected to increase. Since type 2 diabetes mellitus (T2DM) is suffered by the majority of diabetic patients (around 90-95%) and often the mono-target therapy fails in managing blood glucose levels and the other comorbidities, this review focuses on the potential drugs acting on multi-targets involved in the treatment of this type of diabetes. In particular, the review considers the main systems directly involved in T2DM or involved in diabetes comorbidities. Agonists acting on incretin, glucagon systems, as well as on peroxisome proliferation activated receptors are considered. Inhibitors which target either aldose reductase and tyrosine phosphatase 1B or sodium glucose transporters 1 and 2 are taken into account. Moreover, with a view at the multi-target approaches for T2DM some phytocomplexes are also discussed.

Glucose and Blood Pressure-Dependent Pathways-The Progression of Diabetic Kidney Disease

The major clinical associations with the progression of diabetic kidney disease (DKD) are glycemic control and systemic hypertension. Recent studies have continued to emphasize vasoactive hormone pathways including aldosterone and endothelin which suggest a key role for vasoconstrictor pathways in promoting renal damage in diabetes. The role of glucose per se remains difficult to define in DKD but appears to involve key intermediates including reactive oxygen species (ROS) and dicarbonyls such as methylglyoxal which activate intracellular pathways to promote fibrosis and inflammation in the kidney. Recent studies have identified a novel molecular interaction between hemodynamic and metabolic pathways which could lead to new treatments for DKD. This should lead to a further improvement in the outlook of DKD building on positive results from RAAS blockade and more recently newer classes of glucose-lowering agents such as SGLT2 inhibitors and GLP1 receptor agonists.

Prospect of Sodium-Glucose Co-transporter 2 Inhibitors Combined With Insulin for the Treatment of Type 2 Diabetes

Sodium-glucose co-transporter 2 (SGLT2) inhibitors are a new family of antidiabetic drugs that reduce blood glucose independent of insulin. In this review, we present the advantages and adverse effects of SGLT2 inhibitors plus insulin therapy as a treatment regimen for patients with type 2 diabetes (T2D). Compared with placebo, SGLT2 inhibitors plus insulin therapy could significantly decrease fasting blood glucose and HbA1c, thereby reducing the daily required dose of insulin. A reduction in body weight and improvements in insulin resistance and β-cell function have also been widely reported with this therapy, and other potential advantages, including the reduction in blood pressure, adverse cardiovascular outcomes, and visceral adipose tissue volume, have been revealed. SGLT2 inhibitors cause a greater reduction than dipeptidyl peptidase-4 (DPP-4) inhibitors in body weight and the risk of cardiovascular disease. Furthermore, compared with glucagon-like peptide-1 (GLP-1) agonists, SGLT2 inhibitors reduce blood pressure, and heart failure. As this therapy is an oral preparation, an improvement in patient compliance is also achieved. Despite these advantages, however, combination therapy with SGLT2 inhibitors and insulin has several risks. Although no difference has been found in the incidence of hypoglycemic events and urinary tract infection between the administration of this combination and that of placebo, the risk of genital tract infections was reported to increase with the combination therapy. Additionally, bone adverse effects, euglycemic diabetic ketoacidosis, and volume depletion-and osmotic diuresis-related adverse effects have been observed. Altogether, we could conclude that SGLT2 inhibitors plus insulin therapy is an efficient treatment option for patients with T2D, especially those requiring high daily insulin doses and those with insulin resistance, obesity, and a high risk of cardiovascular events. However, careful monitoring of the adverse effects of this combination is also warranted.

Comparison of the urinary glucose excretion contributions of SGLT2 and SGLT1: A quantitative systems pharmacology analysis in healthy individuals and patients with type 2 diabetes treated with SGLT2 inhibitors

AIM

To develop a quantitative drug-disease systems model to investigate the paradox that sodium-glucose co-transporter (SGLT)2 is responsible for >80% of proximal tubule glucose reabsorption, yet SGLT2 inhibitor treatment results in only 30% to 50% less reabsorption in patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

A physiologically based four-compartment model of renal glucose filtration, reabsorption and excretion via SGLT1 and SGLT2 was developed as a system of ordinary differential equations using R/IQRtools. SGLT2 inhibitor pharmacokinetics and pharmacodynamics were estimated from published concentration-time profiles in plasma and urine and from urinary glucose excretion (UGE) in healthy people and people with T2DM.

RESULTS

The final model showed that higher renal glucose reabsorption in people with T2DM versus healthy people was associated with 54% and 28% greater transporter capacity for SGLT1 and SGLT2, respectively. Additionally, the analysis showed that UGE is highly dependent on mean plasma glucose and estimated glomerular filtration rate (eGFR) and that their consideration is critical for interpreting clinical UGE findings.

CONCLUSIONS

Quantitative drug-disease system modelling revealed mechanistic differences in renal glucose reabsorption and UGE between healthy people and those with T2DM, and clearly showed that SGLT2 inhibition significantly increased glucose available to SGLT1 downstream in the tubule. Importantly, we found that the findings of lower than expected UGE with SGLT2 inhibition are explained by the shift to SGLT1, which recovered additional glucose (~30% of total).

Delayed intervention with a novel SGLT2 inhibitor NGI001 suppresses diet-induced metabolic dysfunction and non-alcoholic fatty liver disease in mice

BACKGROUND AND PURPOSE

Non-alcoholic fatty liver disease (NAFLD), including non-alcoholic steatohepatitis, is closely related to metabolic diseases such as obesity and diabetes. Despite an accumulating number of studies, no pharmacotherapy that targets NAFLD has received general approval for clinical use.

EXPERIMENTAL APPROACH

Inhibition of the sodium-glucose cotransporter 2 (SGLT2) is a promising approach to treat diabetes, obesity, and associated metabolic disorders. In this study, we investigated the effect of a novel SGLT2 inhibitor, NGI001, on NAFLD and obesity-associated metabolic symptoms in high-fat diet (HFD)-induced obese mice.

KEY RESULTS

Delayed intervention with NGI001 protected against body weight gain, hyperglycaemia, hyperlipidaemia, and hyperinsulinaemia, compared with HFD alone. Adipocyte hypertrophy was prevented by administering NGI001. NGI001 inhibited impaired glucose metabolism and regulated the secretion of adipokines associated with insulin resistance. In addition, NGI001 supplementation suppressed hepatic lipid accumulation and inflammation but had little effect on kidney function. In-depth investigations showed that NGI001 ameliorated fat deposition and increased AMPK phosphorylation, resulting in phosphorylation of its major downstream target, acetyl-CoA carboxylase, in human hepatocyte HuS-E/2 cells. This cascade ultimately led to the down-regulation of downstream fatty acid synthesis-related molecules and the up-regulation of downstream β oxidation-associated molecules. Surprisingly, NGI001 decreased gene and protein expression of SGLT1 and SGLT2 and glucose uptake in oleic acid-treated HuS-E/2 cells.

CONCLUSION AND IMPLICATIONS

Our findings suggest the novel SGLT2 inhibitor, NGI001 has therapeutic potential to attenuate or delay the onset of diet-induced metabolic diseases and NAFLD.

Dapagliflozin-induced Late-onset Euglycemic Diabetic Ketoacidosis

Sodium-glucose co-transporter-2 (SGLT2) inhibitors are a class of oral hypoglycemics that improve glycemic control by increasing the urinary excretion of glucose. They gained widespread popularity because they not only showed improved glycemic control but also had a favorable effect on weight loss, blood pressure, and cardiovascular mortality. One of their rare side effects is euglycemic diabetic ketoacidosis (eDKA) although the diagnosis is sometimes difficult to make due to near-normal glucose levels. We present a case of eDKA in a patient who presented with confusion, acute kidney injury (AKI), and metabolic acidosis after having an influenza-like illness with a minimally elevated blood glucose of 187 mg/dL. She had already stopped taking dapagliflozin (an SGLT-2 inhibitor) two weeks before the presentation. She was initially treated as sepsis and required hemodialysis. Later on, metabolic acidosis was attributed to eDKA from dapagliflozin, which resolved after the administration of intravenous insulin. Her eDKA developed while she had already stopped dapagliflozin two weeks ago, which makes this an interesting case finding. It is one of those rare cases where dapagliflozin led to a delayed complication of eDKA.

Diabetic nephropathy: an insight into molecular mechanisms and emerging therapies

Introduction: Diabetic kidney disease (DKD) is a major cause of morbidity and mortality in diabetes and is the most common cause of proteinuric and non-proteinuric forms of end-stage renal disease (ESRD). Control of risk factors such as blood glucose and blood pressure is not always achievable or effective. Significant research efforts have attempted to understand the pathophysiology of DKD and develop new therapies. Areas covered: We review DKD pathophysiology in the context of existing and emerging therapies that affect hemodynamic and metabolic pathways. Renin-angiotensin system (RAS) inhibition has become standard care. Recent evidence for renoprotective activity of SGLT2 inhibitors and GLP-1 agonists is an exciting step forward while endothelin receptor blockade shows promise. Multiple metabolic pathways of DKD have been evaluated with varying success; including mitochondrial function, reactive oxygen species, NADPH oxidase (NOX), transcription factors (NF-B and Nrf2), advanced glycation, protein kinase C (PKC), aldose reductase, JAK-STAT, autophagy, apoptosis-signaling kinase 1 (ASK1), fibrosis and epigenetics. Expert opinion: There have been major advances in the understanding and treatment of DKD. SGLT2i and GLP-1 agonists have demonstrated renoprotection, with novel therapies under evaluation. Addressing the interaction between hemodynamic and metabolic pathways may help achieve prevention, attenuation or even reversal of DKD.

Development of sodium glucose co-transporter 2 (SGLT2) inhibitors with novel structure by molecular docking and dynamics simulation

In this study, molecular docking studies were carried out to explore the binding interactions of sodium glucose co-transporter 2 (SGLT2) with its inhibitors. A correlation between the docking scores and the experimental bioactivity was observed (R² = 0.8368, N = 24). The new inhibitors were designed using the 3D quantitative structure activity relationship (3D-QSAR) method, and the activities were predicted by the docking method. In order to understand the structure-activity correlation of compound 1 m (the highest score of docking) and compound 1 t (the lowest score), we carried out a combined molecular dynamics simulation and MM-GBSA method. It was found that, in the system of SGLT2-1 m, the interaction between Gln271 and Val272 exhibited significant effects, which were absent in the SGLT2-1 t system. This study is expected to shed light on the mechanism of action of compound 1 m, leading to development of active drug candidates targeting SGLT2.