Sodium-dependent Glucose Co-transporter 2 Inhibitors Research Articles

Sodium-glucose cotransporter 2 inhibitors ameliorate ER stress-induced pro-inflammatory cytokine expression by inhibiting CD36 in NAFLD progression in vitro

Sodium-dependent glucose cotransporter-2 (SGLT2) inhibitors, antidiabetic drugs that reduce blood sugar levels by inhibiting glucose reabsorption in the renal proximal tubules, also ameliorate nonalcoholic fatty liver disease (NAFLD). This study aimed to examine the effects of SGLT2 inhibition on hepatic steatosis and nonalcoholic steatohepatitis (NASH) using an in vitro model of NAFLD progression. HepG2 cells and a coculture of Hepa1c1c7 and Raw 264.7 cells were treated with 400 μM palmitic acid (PA), followed by treatment with or without 10 μM empagliflozin and dapagliflozin. In HepG2 cells, PA increased hepatic lipid accumulation, the expression of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), exocytosis mediators (VAMP3 and SNAP23), and ER stress markers (GRP78, PERK, IRE1α, ATF6, ATF4, and CHOP), and the gene and protein expression of CD36. SGLT2 inhibitors reversed the effects of PA. SGLT2 inhibition via siRNA reduced proinflammatory-cytokine gene expression in thapsigargin-treated HepG2 cells. Transfection with CD36 siRNA reversed the elevated ATF4 and CHOP expression in PA-treated HepG2 cells. SGLT2 inhibition via an SGTL2 inhibitor and SGLT2 siRNA reduced CD36, Tnf-α, Il-6, Il-1β, Vamp2, Snap23, Atf4, and Chop expression in the PA-treated Hepa1c1c7–Raw 264.7 cell coculture and suppressed Tnf-α release in the Hepa1c1c7–Raw 264.7 cell coculture treated with lipopolysaccharide and PA. These findings indicate that SGLT2 inhibitors inhibited NAFLD progression by reducing hepatic lipid accumulation and inflammation.

Inhibition of Sodium-Glucose Cotransporter-2 during Serum Deprivation Increases Hepatic Gluconeogenesis via the AMPK/AKT/FOXO Signaling Pathway.

Sodium-dependent glucose cotransporter 2 (SGLT2) mediates glucose reabsorption in the renal proximal tubules, and SGLT2 inhibitors are used as therapeutic agents for treating type 2 diabetes mellitus. This study aimed to elucidate the effects and mechanisms of SGLT2 inhibition on hepatic glucose metabolism in both serum deprivation and serum supplementation states. Huh7 cells were treated with the SGLT2 inhibitors empagliflozin and dapagliflozin to examine the effect of SGLT2 on hepatic glucose uptake. To examine the modulation of glucose metabolism by SGLT2 inhibition under serum deprivation and serum supplementation conditions, HepG2 cells were transfected with SGLT2 small interfering RNA (siRNA), cultured in serum-free Dulbecco's modified Eagle's medium for 16 hours, and then cultured in media supplemented with or without 10% fetal bovine serum for 8 hours. SGLT2 inhibitors dose-dependently decreased hepatic glucose uptake. Serum deprivation increased the expression levels of the gluconeogenesis genes peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC-1α), glucose 6-phosphatase (G6pase), and phosphoenolpyruvate carboxykinase (PEPCK), and their expression levels during serum deprivation were further increased in cells transfected with SGLT2 siRNA. SGLT2 inhibition by siRNA during serum deprivation induces nuclear localization of the transcription factor forkhead box class O 1 (FOXO1), decreases nuclear phosphorylated-AKT (p-AKT), and p-FOXO1 protein expression, and increases phosphorylated-adenosine monophosphate-activated protein kinase (p-AMPK) protein expression. However, treatment with the AMPK inhibitor, compound C, reversed the reduction in the protein expression levels of nuclear p- AKT and p-FOXO1 and decreased the protein expression levels of p-AMPK and PEPCK in cells transfected with SGLT2 siRNA during serum deprivation. These data show that SGLT2 mediates glucose uptake in hepatocytes and that SGLT2 inhibition during serum deprivation increases gluconeogenesis via the AMPK/AKT/FOXO1 signaling pathway.

The Impact of SGLT2 Inhibitors in the Heart and Kidneys Regardless of Diabetes Status.

Chronic Kidney Disease (CKD) and Cardiovascular Disease (CVD) are two devastating diseases that may occur in nondiabetics or individuals with diabetes and, when combined, it is referred to as cardiorenal disease. The impact of cardiorenal disease on society, the economy and the healthcare system is enormous. Although there are numerous therapies for cardiorenal disease, one therapy showing a great deal of promise is sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors. The SGLT family member, SGLT2, is often implicated in the pathogenesis of a range of diseases, and the dysregulation of the activity of SGLT2 markedly effects the transport of glucose and sodium across the luminal membrane of renal cells. Inhibitors of SGLT2 were developed based on the antidiabetic action initiated by inhibiting renal glucose reabsorption, thereby increasing glucosuria. Of great medical significance, large-scale clinical trials utilizing a range of SGLT2 inhibitors have demonstrated both metabolic and biochemical benefits via numerous novel mechanisms, such as sympathoinhibition, which will be discussed in this review. In summary, SGLT2 inhibitors clearly exert cardio-renal protection in people with and without diabetes in both preclinical and clinical settings. This exciting class of inhibitors improve hyperglycemia, high blood pressure, hyperlipidemia and diabetic retinopathy via multiple mechanisms, of which many are yet to be elucidated.

Sodium-dependent glucose co-transporter-2 inhibitor empagliflozin exerts neuroprotective effects in rotenone-induced Parkinson’s disease model in zebrafish; mechanism involving ketogenesis and autophagy

Sodium-dependent glucose co-transporter-2 (SGLT2) inhibitor empagliflozin (EMP), is the new class of oral hypoglycemic agent approved as a treatment for Type 2 diabetes. SGLT2 inhibitors may induce ketogenesis through inhibiting the renal reabsorption of glucose. In recent years, positive effects of ketogenic diets on neurodegenerative diseases such as Parkinson's disease (PD) have been reported by improving autophagy. We aimed to evaluate the effects of EMP treatment as a SGLT2 inhibitor that can mimic the effects of ketogenic diet, in rotenone induced PD model in zebrafish focusing on ketogenesis, autophagy, and molecular pathways related with PD progression including oxidative stress and inflammation. Adult zebrafish were exposed to rotenone and EMP for 30 days. Y-Maze task and locomotor analysis were performed. Neurotransmitter levels were determined by liquid chromatography tandem- mass spectrometry (LC-MS/MS). Lipid peroxidation (LPO), nitric oxide (No), alkaline phosphatase, superoxide dismutase, glutathione, glutathione S-transferase (GST), sialic acid, acetylcholinesterase, and the expressions of autophagy, ketogenesis and PD-related genes were determined. Immunohistochemical staining was performed for the microglial marker L-plastin (Lcp1) and tyrosine hydroxylase (Th). EMP treatment improved DOPAC/DA ratio, Y-Maze task, locomotor activity, expressions of Th and Lcp-1, autophagy and inflammation related (mTor, atg5, tnfα, sirt1, il6, tnfα); PD-related (lrrk2, park2, park7, pink1), and ketone metabolism-related genes (slc16a1b, pparag, and pparab), and oxidant-damage in brain in the rotenone group as evidenced by decreased LPO, No, and improved antioxidant molecules. Our results showed benefical effects of EMP as a SGLT2 inhibitor in neurotoxin-induced PD model in zebrafish. We believe our study, will shed light on the mechanism of the effects of SGLT2 inhibitors, ketogenesis and autopahgy in PD.

Physiologically Based Pharmacokinetic Modelling to Predict Pharmacokinetics of Enavogliflozin, a Sodium-Dependent Glucose Transporter 2 Inhibitor, in Humans.

Enavogliflozin is a sodium-dependent glucose cotransporter 2 (SGLT2) inhibitor approved for clinical use in South Korea. As SGLT2 inhibitors are a treatment option for patients with diabetes, enavogliflozin is expected to be prescribed in various populations. Physiologically based pharmacokinetic (PBPK) modelling can rationally predict the concentration-time profiles under altered physiological conditions. In previous studies, one of the metabolites (M1) appeared to have a metabolic ratio between 0.20 and 0.25. In this study, PBPK models for enavogliflozin and M1 were developed using published clinical trial data. The PBPK model for enavogliflozin incorporated a non-linear urinary excretion in a mechanistically arranged kidney model and a non-linear formation of M1 in the liver. The PBPK model was evaluated, and the simulated pharmacokinetic characteristics were in a two-fold range from those of the observations. The pharmacokinetic parameters of enavogliflozin were predicted using the PBPK model under pathophysiological conditions. PBPK models for enavogliflozin and M1 were developed and validated, and they seemed useful for logical prediction.

Angiotensin receptor-neprilysin inhibitor and sodium-dependent glucose cotransporter-2 inhibitor-associated renal injury: a pharmacovigilance study

ABSTRACT Background Angiotensin receptor-neprilysin inhibitor (ARNI) and sodium-dependent glucose cotransporter-2 inhibitors (SGLT-2Is) had a certain risk of renal injury. However, overlapping nephrotoxicity of combination therapy was unclear. Research design and methods We performed a disproportionality analysis based on the Food and Drug Administration Adverse Event Reporting System from 1 January 2004 to 31 December 2020. Renal injury cases were defined as acute kidney injury (AKI) and chronic kidney disease (CKD) cases. Results We detected a significant association between ARNI, SGLT-2Is, the combination therapy and AKI as well as CKD, in which the combination therapy generated the highest strength association with both AKI (ROR: 8.06, 95% CI 5.41–12.01) and CKD (ROR: 2.69, 95% CI 1.27–5.71). Compared with ARNI or SGLT-2I alone, the combination therapy generated AKI signals. There were no differences in the onset time of renal injury cases between the combination therapy and monotherapy. Compared to cases without renal injury, the combination therapy did not increase the proportion of fatality and hospitalizations in cases with AKI or CKD. Conclusion The combination of ARNI and SGLT-2Is was associated with a significantly increased reporting proportion of AKI. However, due to the limitations of the FAERS database, our results required further studies to assess our findings.

Clinical Benefit of Switching from Low-Dose to High-Dose Empagliflozin in Patients with Type 2 Diabetes.

IntroductionSodium-dependent glucose cotransporter 2 (SGLT2) inhibitors ameliorate blood glucose levels in patients with type 2 diabetes mellitus (T2DM) by inhibiting the reabsorption of glucose from the kidneys, thus increasing urinary glucose excretion. Most SGLT2 inhibitors have been reported to exert dose-dependent effects. However, little is known about the benefits of increasing the dose of SGLT2 inhibitors in clinical use. The aim of the present study was to investigate the effect of increasing the dose of the SGLT2 inhibitor empagliflozin in T2DM.MethodsWe collected 52 subjects with T2DM with inadequate glycemic control. The dose of empagliflozin was increased from 10 to 25 mg, taken once daily, and the alterations in glycemic control and several other clinical parameters were evaluated.ResultsThe increased dose of empagliflozin significantly ameliorated glycemic control. In addition, body weight (BW), body mass index (BMI), triglyceride (TG), and γ-glutamyltranspeptidase (GGT) were significantly decreased and hematocrit (Hct) was increased. Multivariate logistic regression analyses revealed that baseline diastolic blood pressure (DBP) (odds ratio 1.093, 95% CI 1.019–1.156, P = 0.012) and baseline TG (odds ratio 1.012, 95% CI 1.001–1.023, P = 0.026) were retained as independent predictors for the improvement of hemoglobin A1c (HbA1c) levels. Moreover, multivariate stepwise regression analyses revealed that changes in high-density lipoprotein cholesterol (β − 0.264, 95% CI − 1.217 to 0.000, P = 0.049) and HbA1c (β 0.302, 95% CI 0.077–1.096, P = 0.025) were retained as independent predictors for changes in BMI.ConclusionIncreasing the dose of empagliflozin significantly ameliorated BW, BMI, GGT, TG, fasting plasma glucose and HbA1c and increased Hct in patients with T2DM. Moreover, baseline DBP and TG were independent predictors for the improvement of HbA1c. These findings may provide useful information when considering increasing the dosage of SGLT2 inhibitors in patients with T2DM who have inadequate glycemic control.Trial RegistrationUMIN Clinical Trials Registry (UMIN000041543).

Dapagliflozin for the treatment of chronic kidney disease

ABSTRACT Introduction Sodium-dependent glucose cotransporter 2 (SGLT2) is a glucose transporter expressed on the proximal tubular cells, where it reabsorbs glucose from the glomerular filtrate. SGLT2 inhibitors (SGLT2is), initially developed as an antidiabetic drug, have recently attracted considerable attention because they have cardiorenal protective effects. Among SGLT2is, dapagliflozin was the first to demonstrate the renoprotective effect in patients with and without diabetes and has been approved for chronic kidney disease (CKD) treatment. Areas covered This review covers the pharmacological characteristics and the clinical efficacy and safety profiles of dapagliflozin, including comparison with other SGLT2is and risk modification strategies. Expert opinion In DAPA-CKD, dapagliflozin reduced the primary outcome (≥50% estimated glomerular filtration rate [eGFR] decline, end-stage kidney disease [ESKD], or renal or cardiovascular [CV] death) by 39% in CKD patients. This beneficial effect was consistent across prespecified subgroups, including those based on the presence of diabetes. Dapagliflozin also decreased the CV composite outcome and all-cause death by 29% and 31%, respectively. Although an increased risk of adverse events such as ketoacidosis and volume depletion has been reported, the robust renal and CV benefits of dapagliflozin are expected to outweigh potential risks. SGLT2is, including dapagliflozin, will constitute the mainstay of CKD treatment.

Discovery of GCC5694A: A potent and selective sodium glucose co-transporter 2 inhibitor for the treatment of type 2 diabetes

Sodium-dependent glucose co-transporter 2 (SGLT2) has emerged as a promising drug target for the treatment of type 2 diabetes, and recently, several SGLT2 inhibitors have been approved for clinical use. A series of molecules with a C-aryl glucoside scaffold was designed and synthesized for biological evaluation. Among the molecules tested, a dihydrobenzofuran-containing analog, 14g (GCC5694A), exhibited excellentin vitro activity against SGLT2 (IC50 = 0.460 nM), good selectivity for SGLT1, and good metabolic stability. Data from further evaluation of the compound in animal models showed that this molecule is a promising candidate for development as an anti-diabetic agent.

Low Phosphate Diet Exacerbates Hypercalciuria in the Jimbee Mouse Model of SGLT2 Loss-of Function

Selective sodium-dependent glucose co-transporter 2 inhibitors (SGLT2is) are a class of anti-hyperglycemic drugs that lower blood glucose in an insulin-independent manner by inhibiting renal glucose reabsorption and promoting glucosuria. In persons with chronic kidney disease, a potential therapeutic target group for such SGLT2i treatment, dietary phosphate restriction is a mainstay of treatment for metabolic bone disease. We investigated the impact of a low phosphate (LP) diet on the physiology of Jimbee mice which, via deletion in exon 10 of the sglt2 gene, provide a model of SGLT2 loss-of-function, albeit with otherwise normal renal function. Male (M) and female (F), 12-week (wk) old, C57BL/6J (genetic control) and Jimbee mice were randomized 1:1 to a kcal/g equivalent 0.1% phosphate (LP) or 0.4% phosphate (normal P = NP) diet and monitored for 12 wks (n=9–12 per group x 8 groups). At study end (~24 wks of age), male Jimbee vs. C57BL/6J mice had lower body mass (BM: p<0.0001), more-so on LP diet (C57BL/6J vs. Jimbee; (M) NP: 31.4 ± 2.1 vs. 28.6 ± 2.0. LP: 30.8 ± 2.0 vs. 26.0 ± 1.6 g). Female mice exhibited no differences in BM. By MRI, male mice demonstrated proportionate decrements in body composition of Jimbees, as the % fat vs. lean mass and % total body water were comparable between genotypes. HbA1c and random blood glucose were no different between groups, while glucosuria was increased in M and F Jimbee mice (p<0.0001) on either diet [C57BL/6J vs. Jimbee; (M) NP: 0.2 ± 0.2 vs. 10.2 ± 4.5. LP: 0.2 ± 0.2 vs. 7.8 ± 2.0 mg/g (body weight)/day. (F) NP: 0.5 ± 0.5 vs. 8.2 ± 2.7. LP: 0.4 ± 0.3 vs. 7.0 ± 2.9 mg/g/day]. Serum calcium and phosphorus were no different between any groups. However, Jimbee mice also exhibited hypercalciuria and hyperphosphaturia (p<0.001 for both). Hypercalciuria was amplified by LP diet in both strains, with a significant diet x strain interaction in males (p=0.01) [C57BL/6J vs. Jimbee; (M) NP: 4.7 ± 2.3 vs. 15.5 ± 8.2. LP: 27.8 ± 31.5 vs. 73.4 ± 25.8 µg/g/day of urine calcium (Ca2+). (F) NP: 4.9 ± 2.8 vs. 22.7 ± 16.9. LP: 45.8 ± 29.5 vs. 62.6 ± 39.8 µg/g/day]. In contrast, hyperphosphaturia was attenuated by LP diet [C57BL/6J vs. Jimbee; (M) NP: 8.7 ± 8.5 vs. 14.7 ± 10.4. LP: 0.9 ± 0.5 vs. 3.2 ± 2.9 µg/g/day of urine phosphate (PO4). (F) NP: 4.4 ± 6.1 vs. 16.3 ± 9.7. LP: 1.2 ± 0.8 vs. 2.9 ± 1.0 µg/g/day]. Plasma PTH levels were significantly lower (p<0.001) in male Jimbee mice on either diet (C57BL/6J vs. Jimbee; NP: 81.1 ± 31.0 vs. 41.3 ± 10.7. LP: 38.2 ± 1.9 vs. 24.1 ± 6.2 pg/mL) and negatively correlated with daily urine Ca2+ (r = -0.62; p=0.006). Consistent with PTH, renal 1-α hydroxylase gene expression was decreased by ~60% in Jimbee males, specifically on LP diet (p=0.02). Together, these data suggest that, in mice, dietary phosphate restriction might exacerbate SGLT2i-related hypercalciuria during prolonged treatment, independent of PTH, becoming potentially detrimental to bone mineralization and growth over time.

Dual-Target Compounds against Type 2 Diabetes Mellitus: Proof of Concept for Sodium Dependent Glucose Transporter (SGLT) and Glycogen Phosphorylase (GP) Inhibitors.

A current trend in the quest for new therapies for complex, multifactorial diseases, such as diabetes mellitus (DM), is to find dual or even multi-target inhibitors. In DM, the sodium dependent glucose cotransporter 2 (SGLT2) in the kidneys and the glycogen phosphorylase (GP) in the liver are validated targets. Several (β-D-glucopyranosylaryl)methyl (het)arene type compounds, called gliflozins, are marketed drugs that target SGLT2. For GP, low nanomolar glucose analogue inhibitors exist. The purpose of this study was to identify dual acting compounds which inhibit both SGLTs and GP. To this end, we have extended the structure-activity relationships of SGLT2 and GP inhibitors to scarcely known (C-β-D-glucopyranosylhetaryl)methyl arene type compounds and studied several (C-β-D-glucopyranosylhetaryl)arene type GP inhibitors against SGLT. New compounds, such as 5-arylmethyl-3-(β-D-glucopyranosyl)-1,2,4-oxadiazoles, 5-arylmethyl-2-(β-D-glucopyranosyl)-1,3,4-oxadiazoles, 4-arylmethyl-2-(β-D-glucopyranosyl)pyrimidines and 4(5)-benzyl-2-(β-D-glucopyranosyl)imidazole were prepared by adapting our previous synthetic methods. None of the studied compounds exhibited cytotoxicity and all of them were assayed for their SGLT1 and 2 inhibitory potentials in a SGLT-overexpressing TSA201 cell system. GP inhibition was also determined by known methods. Several newly synthesized (C-β-D-glucopyranosylhetaryl)methyl arene derivatives had low micromolar SGLT2 inhibitory activity; however, none of these compounds inhibited GP. On the other hand, several (C-β-D-glucopyranosylhetaryl)arene type GP inhibitor compounds with low micromolar efficacy against SGLT2 were identified. The best dual inhibitor, 2-(β-D-glucopyranosyl)-4(5)-(2-naphthyl)-imidazole, had a Ki of 31 nM for GP and IC50 of 3.5 μM for SGLT2. This first example of an SGLT-GP dual inhibitor can prospectively be developed into even more efficient dual-target compounds with potential applications in future antidiabetic therapy.

Protective effects of sodium-dependent glucose cotransporter-2 inhibitors on cardiovascular system

Protective effects of sodium-dependent glucose cotransporter-2 inhibitors on cardiovascular system

Design, synthesis and biological evaluation of 6-deoxy O-spiroketal C-arylglucosides as novel renal sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors for the treatment of type 2 diabetes

In this work, aiming at finding a novel, potent, and selective sodium-dependent glucose cotransporter 2 (SGLT2) inhibitor with good pharmacokinetic profiles for the treatment of diabetes, we focus on modifying the sugar moiety of SGLT2 inhibitors, which dominates the binding with glucose binding site of hSGLT, via removing the C-6 hydroxy group to adjust the physicochemical properties and target-recognition manners of SGLT2 inhibitors. In addition, tofogliflozin containing a special O-spiroketal C-arylglucoside scaffold, displayed good efficacy and bioavailability both in animals and in humans. Therefore, a series of 6-deoxy O-spiroketal C-arylglucosides as novel SGLT2 inhibitors were designed, synthesized, and evaluated in this work. The structure-activity relationship (SAR) research on this novel series and a comprehensive in vitro and in vivo biological evaluation afforded compound 39 with high in vitro hSGLT2 inhibitory activity (IC50 = 4.5 nM), good pharmacokinetic profiles, and more remarkable efficacy in C57BL/6J mice and Sprague-Dawley rats than marketed drug tofogliflozin.

Synthesis and biological evaluation of N-glucosyl indole derivatives as sodium-dependent glucose co-transporter 2 inhibitors

Sodium-dependent glucose co-transporter 2 (SGLT2) inhibition has been demonstrated to efficiently control hyperglycemia via an insulin secretion-independent pathway. The unique mode of action eliminates the risk of hypoglycemia and makes SGLT2 inhibitors an attractive option for the treatment of type 2 diabetes. In a continuation of our previous studies on SGLT2 inhibitors bearing different sugar moieties, sixteen new N-glucosyl indole derivatives were designed, synthesized, and evaluated for their inhibitory activity against hSGLT2. Of these sixteen, acethydrazide-containing N-glucosyl indole 9d was found to be the most potent SGLT2 inhibitor, and caused a significant elevation in urine glucose excretion in rats at 50 mg/kg, relative to the vehicle control.

The Metabolodiuretic Promise of Sodium-Dependent Glucose Cotransporter 2 Inhibition

Clinical trials often yield surprising results, and in the contemporary era, undoubtedly, the Empagliflozin Removal of Excess of Glucose Outcome (EMPA-REG OUTCOME) trial stands out as one such example.1,2 No one could have predicted that a sodium-dependent glucose cotransporter 2 (SGLT2) inhibitor, which works to promote urinary glucose excretion as a treatment approach to hyperglycemia, would cut all-cause mortality by about one-third in patients with type 2 diabetes. Just as surprising were the observations that the reductions in mortality were possibly driven by a reduction in heart failure as opposed to atherothrombotic events. Despite these salutary clinical effects, the physiological mechanisms responsible for these benefits are not yet known. The time frame of the effect precludes a glucose-mediated effect, and furthermore, many other equally or more effective antihyperglycemic therapies are not associated with reduced heart failure. The remarkable renal benefits noted in the trial were also surprising.2 Because the glycosuric effects of SGLT2 inhibition are dependent on the amount of filtered glucose and therefore diminished in participants with low glomerular filtration rate, it was surprising to note that treatment with empagliflozin resulted in a marked approximately 40% reduction in proteinuria and doubling of serum creatinine in the absence of marked differences in glycemia. While the scientific community struggles to understand the biologic basis and clinical implications of these observations, several questions related to EMPA-REG OUTCOME have come into focus: can SGLT2 inhibitors be used to treat heart failure as opposed to prevent heart failure in diabetes? Can SGLT2 inhibitors be a treatment for heart failure in patients without type 2 diabetes? It is also tempting to ask whether SGLT2 inhibitors will emerge as primary renoprotective strategies irrespective of glycemic or baseline renal status.

Cardioprotective effects of SGLT2 inhibitors are possibly associated with normalization of the circadian rhythm of blood pressure.

Improvement in cardiovascular (CV) morbidity and mortality in the EMPA-REG OUTCOME study provides new insight into the therapeutic use of sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors in patients with type 2 diabetes. Although SGLT2 inhibitors have several pleiotropic effects, the underlying mechanism responsible for their cardioprotective effects remains undetermined. In this regard, the absence of a nocturnal fall in blood pressure (BP), that is, non-dipping BP, is a common phenomenon in type 2 diabetes and has a crucial role in the pathogenesis of CV morbidity and mortality. In most clinical trials, SGLT2 inhibitors reduce both systolic BP (~3-5 mm Hg) and diastolic BP (~2 mm Hg) in patients with type 2 diabetes. In addition, recent clinical and animal studies have revealed that SGLT2 inhibitors enable the change in BP circadian rhythm from a non-dipper to a dipper type, which is possibly associated with the improvement in CV outcomes in patients with type 2 diabetes. In this review, recent data on the effect of SGLT2 inhibitors on the circadian rhythm of BP will be summarized. The possible underlying mechanisms responsible for the SGLT2 inhibitor-induced improvement in the circadian rhythm of BP will also be discussed.

Predicting the biological activities of triazole derivatives as SGLT2 inhibitors using multilayer perceptron neural network, support vector machine, and projection pursuit regression models

Quantitative structure–activity relationship (QSAR) studies were performed in this work to predict the pIC50 of non-glycoside sodium-dependent glucose cotransporter-2 (SGLT2) inhibitors (46 triazole derivatives). Four descriptors were selected from the pool of DRAGON descriptors using the enhanced replacement method. Three nonlinear regression methods—multilayer perceptron neural network (MLP NN), support vector machine (SVM), and projection pursuit regression (PPR)—were then used to build the QSAR models. The performance of the obtained models was assessed through the cross-validation and external validation of the test set. PPR produced a better model than MLP NN and SVM with coefficients of determination of 0.962 and 0.871 and root mean square errors of 0.162 and 0.471 for the training and test sets, respectively. This study developed simple and efficient approaches to predict the pIC50 of triazole derivatives and provided some insights into their structural features for the development of more potential SGLT2 inhibitors.

Development and validation of an LC-MS/MS method for the determination of tofogliflozin in plasma and its application to a pharmacokinetic study in rats.

Tofogliflozin is a novel selective inhibitor of sodium-dependent glucose co-transporter-2 (SGLT2) and has been developed for the treatment of patients with type 2 diabetes mellitus. In this study, a highly sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantitation of tofogliflozin in rat plasma was developed and validated. The detection was performed using an API 3200 triple-quadrupole mass spectrometer with selected reaction monitoring (SRM) in the positive electrospray ionization mode. The SRM transitions were m/z=387.1 [M+H](+)→267.1 for tofogliflozin and m/z=451.2 [M+H](+)→71.0 for empagliflozin (internal standard: I.S.). Chromatographic separation was performed on a Quicksorb ODS (2.1mm i.d.×150mm, 5μm size) using isocratic elution with acetonitrile/10mM ammonium acetate (50:50, v/v) as the mobile phase at a flow rate of 0.2mL/min and the total run time was 4.0min. The lower limit of quantification (LLOQ) for tofogliflozin was 0.5ng/mL with sufficient specificity, accuracy, and precision. The validated method was successfully applied to the pharmacokinetic studies of tofogliflozin in rats. This assay method could be a valuable tool for future studies including pharmacokinetic and pharmacodynamic studies of SGLT2 inhibitors.

N-Indolylglycosides bearing modifications at the glucose C6-position as sodium-dependent glucose co-transporter 2 inhibitors

Suppression of glucose reabsorption through the inhibition of sodium-dependent glucose co-transporter 2 (SGLT2) is a promising therapeutic approach for the treatment of type 2 diabetes. To investigate the effect of C6-substitution on inhibition of SGLT2 by N-indolylglucosides, a small library of 6-triazole, 6-amide, 6-urea, and 6-thiourea N-indolylglycosides were synthesized and tested. A detailed structure–activity relationship (SAR) study culminated in the identification of 6-amide derivatives 6a and 6o as potent SGLT2 inhibitors, which were further tested for inhibitory activity against SGLT1. The data obtained indicated that 6a and 6o are mildly to moderately selective for SGLT2 over SGLT1. Both compounds were also evaluated in a urinary glucose excretion test and pharmacokinetic study; 6a was found capable of inducing urinary glucose excretion in normal SD rats.

Design of SGLT2 Inhibitors for the Treatment of Type 2 Diabetes: A History Driven by Biology to Chemistry

A brief history of the design of sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors is reviewed. The design of O-glucoside SGLT2 inhibitors by structural modification of phlorizin, a naturally occurring O-glucoside, in the early stage was a process mainly driven by biology with anticipation of improving SGLT2/SGLT1 selectivity and increasing metabolic stability. Discovery of dapagliflozin, a pioneering C-glucoside SGLT2 inhibitor developed by Bristol-Myers Squibb, represents an important milestone in this history. In the second stage, the design of C-glycoside SGLT2 inhibitors by modifications of the aglycone and glucose moiety of dapagliflozin, an original structural template for almost all C-glycoside SGLT2 inhibitors, was mainly driven by synthetic organic chemistry due to the challenge of designing dapagliflozin derivatives that are patentable, biologically active and synthetically accessible. Structure-activity relationships (SAR) of the SGLT2 inhibitors are also discussed.