What does sodium-glucose co-transporter 1 inhibition add: Prospects for dual inhibition

New functions and roles of the Na+-H+-exchanger NHE3

The sodium/proton exchanger isoform 3 (NHE3) is expressed in the intestine and the kidney, where it contributes to hydrogen secretion and sodium (re)absorption. The roles of this transporter have been studied by the use of the respective knockout mice and by using pharmacological inhibitors. Whole-body NHE3 knockout mice suffer from a high mortality rate (with only ∼30% of mice surviving into adulthood), and based on the expression of NHE3 in both intestine and kidney, some conclusions that were originally derived were based on this rather complex phenotype. In the last decade, more refined models have been developed that added temporal and spatial control of NHE3 expression. For example, novel mouse models have been developed with a knockout of NHE3 in intestinal epithelial cells, tubule/collecting duct of the kidney, proximal tubule of the kidney, and thick ascending limb of the kidney. These refined models have significantly contributed to our understanding of the role of NHE3 in a tissue/cell type-specific manner. In addition, tenapanor was developed, which is a non-absorbable, intestine-specific NHE3 inhibitor. In rat and human studies, tenapanor lowered intestinal Pi uptake and was effective in lowering plasma Pi levels in patients on hemodialysis. Of note, diarrhea is seen as a side effect of tenapanor (with its indication for the treatment of constipation) and in intestine-specific NHE3 knockout mice; however, effects on plasma Pi were not supported by this mouse model which showed enhanced and not reduced intestinal Pi uptake. Further studies indicated that the gut microbiome in mice lacking intestinal NHE3 resembles an intestinal environment favoring the competitive advantage of inflammophilic over anti-inflammatory species, something similar seen in patients with inflammatory bowel disease. This review will highlight recent developments and summarize newly gained insight from these refined models.

Differing Efficacy of Dapagliflozin Versus Empagliflozin on the Risk of Incident Atrial Fibrillation in Patients With Type 2 Diabetes: A Real-World Observation Using a Nationwide, Population-Based Cohort

BACKGROUND

Meta-analyses of large clinical trials investigating SGLT2 (sodium-glucose cotransporter-2) inhibitors have suggested their protective effects against atrial fibrillation in patients with type 2 diabetes. However, the results were predominantly driven from trials involving dapagliflozin.

METHODS AND RESULTS

We used a nationwide, population-based cohort of patients with type 2 diabetes who initiated either dapagliflozin or empagliflozin between May 2016 and December 2018. An active-comparator, new-user design was used, and the 2 groups of patients were matched using propensity scores. The primary outcome was incident nonvalvular atrial fibrillation, which was analyzed using both the main intention-to-treat and sensitivity analysis that censored patients who skipped their medications for ≥30 days. Men ≥55 years of age and women ≥60 years of age with ≥1 traditional risk factor or those with established cardiovascular disease were categorized as high cardiovascular risk group. Patients not included in the high-risk group were categorized as low risk. After 1:1 propensity-score matching, a total of 137 928 patients (mean age, 55 years; 58% men) were included and followed up for 2.2±0.6 years. The risk of incident atrial fibrillation was significantly lower in the dapagliflozin group in both the main (hazard ratio [HR], 0.885 [95% CI, 0.789-0.992]) and sensitivity analyses (HR, 0.835 [95% CI, 0.719-0.970]). Notably, this was consistent in both the low and high cardiovascular risk groups. There was no effect modification by age, sex, body mass index, duration of diabetes, or renal function.

CONCLUSIONS

This real-world, population-based study demonstrates that patients with type 2 diabetes using dapagliflozin may have a lower risk of developing nonvalvular atrial fibrillation than those using empagliflozin.

Effect of pharmacological selectivity of SGLT2 inhibitors on cardiovascular outcomes in patients with type 2 diabetes: a meta-analysis

Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce major adverse cardiovascular events (MACE) in type 2 diabetic (T2DM) patients. Pharmacological selectivity of these agents to SGLT2 over SGLT1 is highly variant, with unknown clinical relevance. Genetically reduced SGLT1-but not SGLT2-activity correlates with lower risk of heart failure and mortality, therefore additional non-selective SGLT1 inhibition might be beneficial. In this prespecified meta-analysis, we included 6 randomized, placebo-controlled cardiovascular outcome trials of SGLT2 inhibitors assessing MACE in 57,553 patients with T2DM. Mixed-effects meta-regression revealed that pharmacological selectivity of SGLT2 inhibitors (either as continuous or dichotomized variable) had no significant impact on most outcomes. However, lower SGLT2 selectivity correlated with significantly lower risk of stroke (pseudo-R2 = 78%; p = 0.011). Indeed, dual SGLT1/2 inhibitors significantly reduced the risk of stroke (hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.64-0.94), unlike selective agents (p for interaction = 0.018). The risk of diabetic ketoacidosis and genital infections was higher in both pharmacological groups versus placebo. However, hypotension occurred more often with non-selective SGLT2 inhibitors (odds ratio [OR], 1.87; 95% CI, 1.20-2.92) compared with selective agents (p for interaction = 0.044). In conclusion, dual SGLT1/2 inhibition reduces stroke in high-risk T2DM patients but has limited additional effect on other clinical outcomes.

SGLT2 Inhibitors: Paradigm Shift from Diabetes Care to Metabolic Care-An Indian Perspective

The prevalence and burden of diabetes are on the rise in India, making it 'the diabetes capital of the world'. Comorbidities such as obesity, cardiovascular (CV) complications, chronic kidney disease (CKD), non-alcoholic fatty liver disease (NAFLD), and neurodegenerative diseases are common in patients with diabetes. Recent breakthroughs in diabetes medications and continuous glucose monitoring have resulted in a paradigm shift in diabetes care. Hence, a review in the Indian context is warranted. This review focuses on the existing evidence (gathered by a systematic literature search utilising online databases such as PubMed) on the metabolic, cardio-renoprotective, and hepatoprotective effects of sodium-glucose co-transporter 2 (SGLT2) inhibition, particularly in the Indian setting. The study revealed that the SGLT2 inhibitors (SGLT2i), with their numerous pleiotropic benefits, have received considerable attention recently as a novel class of antihyperglycaemic agents (AHAs) for the management of diabetes. SGLT2i play a crucial role in the transition from glycaemic control to metabolic care, particularly in the context of obesity, CV disease and renal disease. In addition to improving glycaemic control, SGLT2i have been shown to promote weight loss, reduce blood pressure and improve lipid profiles, which are key components of metabolic health. Moreover, SGLT2i have demonstrated renal protective effects, including a reduction in albuminuria and a slower decline in the estimated glomerular filtration rate (eGFR), suggesting a potential role in the management of renal dysfunction.

Empagliflozin reduces endoplasmic reticulum stress associated TXNIP/NLRP3 activation in tunicamycin-stimulated aortic endothelial cells

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have proven to be of therapeutic significance for cardiovascular diseases beyond the treatment of type 2 diabetes. Recent studies have demonstrated the beneficial effects of SGLT2i on endothelial cell (EC) dysfunction, but the underlying cellular mechanisms remain to be clarified. In this study, we sought to understand the effect of empagliflozin (EMPA; Jardiance®) on cell homeostasis and endoplasmic reticulum (ER) stress signaling. ER stress was induced by tunicamycin (Tm) in human abdominal aortic ECs treated with EMPA over 24 h. Tm-induced ER stress caused increases in the protein expression of thioredoxin interacting protein (TXNIP), NLR-family pyrin domain-containing protein 3 (NLRP3), C/EBP homologous protein (CHOP), and in the ratio of phospho-eIF2α/eIF2α. EMPA (50-100 µM) resulted in a dampened downstream activation of ER stress as seen by the reduced expression of CHOP and TXNIP/NLRP3 in a dose-dependent manner. Nuclear factor erythroid 2-related factor 2 (nrf2) translocation was also attenuated in EMPA-treated ECs. These results suggest that EMPA improves redox signaling under ER stress which in turn attenuates the activation of TXNIP/NLRP3.

Comparison of SGLT1, SGLT2, and Dual Inhibitor biological activity in treating Type 2 Diabetes Mellitus

Diabetes Mellitus Type 2 (T2D) is an emerging health burden in the USand worldwide, impacting approximately 15% of Americans. Current front-line therapeutics for T2D patients include sulfonylureas that act to reduce A1C and/or fasting blood glucose levels, or Metformin that antagonizes the action of glucagon to reduce hepatic glucose production. Next generation glucomodulatory therapeutics target members of the high-affinity glucose transporter Sodium-Glucose-Linked-Transporter (SGLT) family. SGLT1 is primarily expressed in intestinal epithelium, whose inhibition reduces dietary glucose uptake, whilst SGLT2 is highly expressed in kidney - regulating glucose reabsorption. A number of SGLT2 inhibitors are FDA approved whilst SGLT1 and dual SGLT1 & 2 inhibitor are currently in clinical trials. Here, we discuss and compare SGLT2, SGLT1, and dual inhibitors' biochemical mechanism and physiological effects.

Sotagliflozin: Efficacy, Safety, and Potential Therapeutic Applications in Heart Failure

OBJECTIVE

To describe the pharmacology, clinical efficacy, and safety evidence of sotagliflozin, the first approved dual inhibitor of sodium-glucose cotransporter (SGLT) 1 and SGLT2, in heart failure (HF) management.

DATA SOURCES

A literature search of studies published between January 2012 and September 2023 were identified using PubMed, MEDLINE, and clinicaltrials.gov with search terms of "sotagliflozin," "Inpefa," or "LX4211."

STUDY SELECTION AND DATA EXTRACTION

All available studies in English were considered. Studies were included if they investigated drug pharmacology, efficacy, or safety information.

DATA SYNTHESIS

Two phase 3 trials of sotagliflozin, SOLOIST-WHF and SCORED, evaluated sotagliflozin compared with placebo in patients with type 2 diabetes mellitus (T2DM). SOLOIST-WHF reported a statistically decreased rate of cardiovascular and HF events with sotagliflozin (hazard ratio [HR] = 0.67, 95% CI = 0.52-0.85), while SCORED found a statistically significant decrease in incidence of cardiovascular events in patients with T2DM, chronic kidney disease (CKD), and risk factors for cardiovascular disease in patients in the sotagliflozin group (HR = 0.74, 95% CI = 0.63-0.88).

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON TO EXISTING AGENTS

While approval of sotagliflozin expands treatment options for patients with HF, the SGLT2 inhibitors, dapagliflozin and empagliflozin, have more data supporting their use in HF, additional risk reduction benefits in patients with CKD, and approval for use in T2DM. Landmark trials of sotagliflozin required a previous diagnosis of T2DM, despite the broader approved indication. Where sotagliflozin will be adopted into the treatment of HF is unclear due to the evidence and benefits of already established SGLT2 inhibitors and the need for comparison with SGLT2 inhibitors.

CONCLUSION

Given the limitations of currently available evidence, including difficulty in fully interpreting the trial results due to changes in primary endpoints, not adjudicating the events, and not reaching the original power calculations, more investigation is warranted to determine the benefit of sotagliflozin compared with SGLT2 inhibitors.

Efficacy of Sotagliflozin in Adults With Type 2 Diabetes in Relation to Baseline Hemoglobin A1c

BACKGROUND

The SCORED (Effect of Sotagliflozin on Cardiovascular and Renal Events in Patients with Type 2 Diabetes and Moderate Renal Impairment Who Are at Cardiovascular Risk) and SOLOIST-WHF (Effect of Sotagliflozin on Cardiovascular Events in Patients with Type 2 Diabetes Post Worsening Heart Failure) trials demonstrated that sotagliflozin, an SGLT1 and SGLT2 inhibitor, improves outcomes in individuals with type 2 diabetes who have heart failure (HF) or kidney disease.

OBJECTIVES

We assessed the efficacy of sotagliflozin on HF clinical outcomes in individuals with differing baseline glycosylated hemoglobin (HbA1c) levels.

METHODS

We included all adults from SCORED and SOLOIST-WHF. The primary outcome was a composite of cardiovascular death, hospitalizations for HF, and urgent visits for HF. The efficacy of sotagliflozin compared with placebo was evaluated by baseline HbA1c using competing-risk marginal proportional hazards models.

RESULTS

We identified 11,744 adults. Individuals with HbA1c ≤7.5% experienced the primary outcome at a lower rate in the sotagliflozin group (11.2 per 100 person-years) than the placebo group (15.5 per 100 person-years) (HR: 0.73; 95% CI: 0.57-0.93). Similarly, individuals with HbA1c of 7.6% to 9.0% experienced the primary outcome at a lower rate in the sotagliflozin group (7.3 per 100 person-years) than the placebo group (9.4 per 100 person-years) (HR: 0.77; 95% CI: 0.63-0.96). These findings were also consistent among individuals with HbA1c >9.0%, with a primary outcome rate in the sotagliflozin group (7.8 per 100 person-years) that was lower than the placebo group (11.6 per 100 person-years) (HR: 0.65; 95% CI: 0.50-0.84). The efficacy of sotagliflozin was consistent by baseline HbA1c level (P for interaction = 0.58).

CONCLUSIONS

In individuals with type 2 diabetes and either HF or kidney disease, sotagliflozin reduced HF outcomes irrespective of baseline HbA1c.

A pharmacokinetic study to correlate the hypoglycemic effect of phlorizin in rats: Identification of metabolites as inhibitors of sodium/glucose cotransporters

Phlorizin (PRZ) is a natural product that belongs to a class of dihydrochalcones. The unique pharmacological property of PRZ is to block glucose absorption or reabsorption through specific and competitive inhibitors of the sodium/glucose cotransporters (SGLTs) in the intestine (SGLT1) and kidney (SGLT2). This results in glycosuria by inhibiting renal reabsorption of glucose and can be used as an adjuvant treatment for type 2 diabetes. The pharmacokinetic profile, metabolites of the PRZ, and efficacy of metabolites towards SGLTs are unknown. Therefore, the present study on the characterization of hitherto unknown in vivo metabolites of PRZ and pharmacokinetic profiling using liquid chromatography-electrospray ionization tandem mass spectrometry (LC/ESI/MS/MS) and accurate mass measurements is undertaken. Plasma, urine, and feces samples were collected after oral administration of PRZ to Sprague-Dawley rats to identify in vivo metabolites. Furthermore, in silico efficacy of the identified metabolites was evaluated by docking study. PRZ at an intraperitoneal dose of 400 mg/kg showed maximum concentration in the blood to 439.32 ± 8.84 ng/mL at 1 h, while phloretin showed 14.38 ± 0.33 ng/mL at 6 h. The pharmacokinetic profile of PRZ showed that the maximum concentration lies between 1 and 2 h after dosing. Decreased blood glucose levels and maximum excretion of glucose in the urine were observed when the PRZ and metabolites were observed in plasma. The identification and characterization of PRZ metabolites by LC/ESI/MS/MS further revealed that the phase I metabolites of PRZ are hydroxy (mono-, di-, and tri-) and reduction. Phase II metabolites are O-methylated, O-acetylated, O-sulfated, and glucuronide metabolites of PRZ. Further docking study revealed that the metabolites diglucuronide metabolite of mono-hydroxylated PRZ and mono-glucuronidation of PRZ could be considered novel inhibitors of SGLT1 and SGLT2, respectively, which show better binding affinities than their parent compound PRZ and the known inhibitors.

Comparative cardiovascular outcomes in type 2 diabetes patients taking dapagliflozin versus empagliflozin: a nationwide population-based cohort study

BACKGROUND

Sodium-glucose co-transporter-2 inhibitors displayed cardiovascular benefits in type 2 diabetes mellitus in previous studies; however, there were some heterogeneities regarding respective cardiovascular outcomes within the class. Furthermore, their efficacies in Asians, females, and those with low cardiovascular risks were under-represented. Thus, we compared the cardiovascular outcomes between new users of dapagliflozin and empagliflozin in a broad range of patients with type 2 diabetes mellitus using a nationwide population-based real-world cohort from Korea.

METHODS

Korean National Health Insurance registry data between May 2016 and December 2018 were extracted, and an active-comparator new-user design was applied. The primary outcome was a composite of heart failure (HF)-related events (i.e., hospitalization for HF and HF-related death), myocardial infarction, ischemic stroke, and cardiovascular death. The secondary outcomes were individual components of the primary outcome.

RESULTS

A total of 366,031 new users of dapagliflozin or empagliflozin were identified. After 1:1 nearest-neighbor propensity score matching, 72,752 individuals (mean age approximately 56 years, 42% women) from each group were included in the final analysis, with a follow-up of 150,000 ~ person-years. Approximately 40% of the patients included in the study had type 2 diabetes mellitus as their sole cardiovascular risk factor, with no other risk factors. The risk of the primary outcome was not different significantly between dapagliflozin and empagliflozin users (hazard ratio [HR] 0.93, 95% confidence interval [CI] 0.855-1.006). The risks of secondary outcomes were also similar, with the exception of the risks of HF-related events (HR 0.84, 95% CI 0.714-0.989) and cardiovascular death (HR 0.76, 95% CI 0.618-0.921), which were significantly lower in the dapagliflozin users.

CONCLUSIONS

This large-scale nationwide population-based real-world cohort study revealed no significant difference in composite cardiovascular outcomes between new users of dapagliflozin and empagliflozin. However, dapagliflozin might be associated with lower risks of hospitalization or death due to HF and cardiovascular death than empagliflozin in Asian patients with type 2 diabetes mellitus.

Influence of SGLT1 Sugar Uptake Inhibitors on Water Transport

Sodium glucose cotransporters (SGLTs) are cotransporters located in the cell membrane of various epithelia that uptake glucose or galactose and sodium into the cell. Its founding member, SGLT1, represents a major pharmaceutically relevant target protein for development of new antidiabetic drugs, in addition to being the target protein of the oral rehydration therapy. Previous studies focused primarily on the transport of substrates and ions, while our study focuses on the effect of water transport. SGLT1 is implicated in the absorption of water, yet the exact mechanism of how the water absorption occurs or how inhibitors of SGLT1, such as phlorizin, are able to inhibit it is still unclear. Here we present a comprehensive study based on molecular dynamics simulations with the aim of determining the influence of the energetic and dynamic properties of SGLT1, which are influenced by selected sugar uptake inhibitors on water permeation.

Mechanistic evaluation of the inhibitory effect of four SGLT-2 inhibitors on SGLT 1 and SGLT 2 using physiologically based pharmacokinetic (PBPK) modeling approaches

Sodium-glucose co-transporter type 2 (SGLT 2, gliflozins) inhibitors are potent orally active drugs approved for managing type 2 diabetes. SGLT 2 inhibitors exert a glucose-lowering effect by suppressing sodium-glucose co-transporters 1 and 2 in the intestinal and kidney proximal tubules. In this study, we developed a physiologically based pharmacokinetic (PBPK) model and simulated the concentrations of ertugliflozin, empagliflozin, henagliflozin, and sotagliflozin in target tissues. We used the perfusion-limited model to illustrate the disposition of SGLT 2 inhibitors in vivo. The modeling parameters were obtained from the references. Simulated steady-state plasma concentration-time curves of the ertugliflozin, empagliflozin, henagliflozin, and sotagliflozin are similar to the clinically observed curves. The 90% prediction interval of simulated excretion of drugs in urine captured the observed data well. Furthermore, all corresponding model-predicted pharmacokinetic parameters fell within a 2-fold prediction error. At the approved doses, we estimated the effective concentrations in intestinal and kidney proximal tubules and calculated the inhibition ratio of SGLT transporters to differentiate the relative inhibition capacities of SGLT1 and 2 in each gliflozin. According to simulation results, four SGLT 2 inhibitors can nearly completely inhibit SGLT 2 transporter at the approved dosages. Sotagliflozin exhibited the highest inhibition activity on SGLT1, followed by ertugliflozin, empagliflozin, and henagliflozin, which showed a lower SGLT 1 inhibitory effect. The PBPK model successfully simulates the specific target tissue concentration that cannot be measured directly and quantifies the relative contribution toward SGLT 1 and 2 for each gliflozin.

From Kidney Protection to Stroke Prevention: The Potential Role of Sodium Glucose Cotransporter-2 Inhibitors

Chronic kidney disease (CKD) is an independent risk factor for stroke and covert cerebrovascular disease, and up to 40% of stroke patients have concomitant CKD. However, the so-called "cerebrorenal interaction" attracted less attention compared to its cardiorenal counterpart. Diabetes is the leading cause of CKD. The sodium-glucose cotransporter (SGLT) 2 inhibitor is a relatively new class of oral anti-diabetic drugs and has cardiorenal benefits in addition to glucose-lowering effects. In the present perspective, we would like to review the current status and future potential of the SGLT2 inhibitor in cerebro-renal interactions and strokes regardless of the status of diabetes. We propose the potential roles of baseline renal functions and SGLT1/2 dual inhibition in stroke prevention, as well as the additional benefits of reducing atrial fibrillation and hemorrhagic stroke for SGLT2 inhibitors. Further clinical trials are anticipated to test whether SGLT2 inhibitors can fulfill the long-standing unmet clinical need and stop such a vicious cycle of cerebro-renal interaction.

Development and optimization of amphiphilic self-assembly into nanostructured liquid crystals for transdermal delivery of an antidiabetic SGLT2 inhibitor

The anti-hyperglycemic sodium glucose co-transporter 2 inhibitor Canagliflozin (CFZ) represents a recent antihyperglycemic modality, yet it suffers from low oral bioavailability. The current work aims to formulate CFZ-loaded transdermal nanostructured liquid crystal gel matrix (NLCG) to improve its therapeutic efficiency. Pre-formulation study included the construction of pseudoternary phase diagrams to explore the effect of two conventional amphiphiles against amphiphilic tri-block copolymer in the formulation of NLCG. The influence of different co-solvents was also investigated with the use of monooleine as the oil. Physical characterization, morphological examination and skin permeation were performed for the optimized formulations. The formula of choice was further investigated for skin irritation and chemical stability. Pharmacodynamic evaluation of the successful formula was conducted on hyperglycemic as well as normoglycemic mice. In addition, oral glucose tolerance test was conducted. Results revealed the supremacy of Poloxamer for stabilizing and maximizing liquid crystal gel (LCG) area percentage that reached up to 12.6%. CFZ-NLCG2 isotropic formula showed the highest permeation parameters; maximum flux value of 7460 μg/cm² h and Q₂₄ of 5327 μg/cm². Pharmacodynamic evaluation revealed the superiority of the antihyperglycemic activity of CFZ-NLCG2 in fasting mice and its equivalence in the oral glucose tolerance test (OGTT) compared to the oral one. The obtained results confirmed the success of CFZ-NLCG2 in the transdermal delivery of CFZ in therapeutically effective concentration compared to the oral route, bypassing first pass effect; in addition, eliminates the possible gastrointestinal side effects related to the inhibition of intestinal sodium glucose co-transporter (SGLT) and maximizes its selectivity to the desired inhibition of renal SGLT.

Dose-dependent efficacy and safety of licogliflozin on obese adults: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Licogliflozin is a dual SGLT1/2 inhibitor acting on the intestine and kidney by reducing glycemic and calorie content. We aimed to determine the efficacy and safety of licogliflozin on Anthropometric measurements and cardiometabolic parameters in obese participants.

METHODS

We systematically searched the PubMed, Cochrane Library, Scopus, and Web of Science databases for randomized controlled trials (RCTs) relevant to our eligibility criteria. We performed a subgroup analysis based on licogliflozin doses and the diabetic state of participants. This meta-analysis was registered on PROSPERO (CRD42021286936).

RESULTS

We identified five RCTs with a total of 905 obese and overweight participants. All participants had a weight reduction of 2.43 kg (95% CI: -3.17 to -1.69, p < 0.00001) compared with placebo. The mean difference in HbA1c of obese diabetic patients was (MD: -0.30%; 95% CI: -0.45, -0.16); I2 = 46% in favor of licogliflozin. The incidence of serious adverse events, all-cause mortality, headache, nausea, and vomiting were similar between licogliflozin and placebo (p = 0.72, 0.97, 0.09, 0.53, and 0.89, respectively). However, there was a higher incidence of diarrhea in the licogliflozin group.

CONCLUSION

We found that licogliflozin was safe and tolerable. It reduces body weight significantly. Moreover, it improves glycemic control and other cardiometabolic parameters.

Structural mechanism of SGLT1 inhibitors

Sodium glucose co-transporters (SGLT) harness the electrochemical gradient of sodium to drive the uphill transport of glucose across the plasma membrane. Human SGLT1 (hSGLT1) plays a key role in sugar uptake from food and its inhibitors show promise in the treatment of several diseases. However, the inhibition mechanism for hSGLT1 remains elusive. Here, we present the cryo-EM structure of the hSGLT1-MAP17 hetero-dimeric complex in the presence of the high-affinity inhibitor LX2761. LX2761 locks the transporter in an outward-open conformation by wedging inside the substrate-binding site and the extracellular vestibule of hSGLT1. LX2761 blocks the putative water permeation pathway of hSGLT1. The structure also uncovers the conformational changes of hSGLT1 during transitions from outward-open to inward-open states.

Enterocyte HKDC1 Modulates Intestinal Glucose Absorption in Male Mice Fed a High-fat Diet

Hexokinase domain containing protein-1, or HKDC1, is a widely expressed hexokinase that is genetically associated with elevated 2-hour gestational blood glucose levels during an oral glucose tolerance test, suggesting a role for HKDC1 in postprandial glucose regulation during pregnancy. Our earlier studies utilizing mice containing global HKDC1 knockdown, as well as hepatic HKDC1 overexpression and knockout, indicated that HKDC1 is important for whole-body glucose homeostasis in aging and pregnancy, through modulation of glucose tolerance, peripheral tissue glucose utilization, and hepatic energy storage. However, our knowledge of the precise role(s) of HKDC1 in regulating postprandial glucose homeostasis under normal and diabetic conditions is lacking. Since the intestine is the main entry portal for dietary glucose, here we have developed an intestine-specific HKDC1 knockout mouse model, HKDC1Int-/-, to determine the in vivo role of intestinal HKDC1 in regulating glucose homeostasis. While no overt glycemic phenotype was observed, aged HKDC1Int-/- mice fed a high-fat diet exhibited an increased glucose excursion following an oral glucose load compared with mice expressing intestinal HKDC1. This finding resulted from glucose entry via the intestinal epithelium and is not due to differences in insulin levels, enterocyte glucose utilization, or reduction in peripheral skeletal muscle glucose uptake. Assessment of intestinal glucose transporters in high-fat diet-fed HKDC1Int-/- mice suggested increased apical GLUT2 expression in the fasting state. Taken together, our results indicate that intestinal HKDC1 contributes to the modulation of postprandial dietary glucose transport across the intestinal epithelium under conditions of enhanced metabolic stress, such as high-fat diet.

Cognitive impairment and type 2 diabetes mellitus: Focus of SGLT2 inhibitors treatment

Gliflozins are a novel class of oral anti-diabetic drugs, acting as inhibitors of sodium-glucose co-transporters (SGLTs) through the proximal convoluted tubules (PCT) and intestinal epithelium. The sodium-glucose co-transporters 2 (SGLT2) are mainly expressed in S1 and S2 segments of the proximal convoluted tubule in the kidneys. Clinical guidelines recommend their use especially in Type 2 Diabetes mellitus (T2DM) patients with vascular complications and/or heart failure highlighting the importance of sodium-glucose co-transporter 2 inhibitors (SGLT2i) pleiotropic effects. Interestingly, cognitive decline is a widely recognized complication of T2DM and, in addition, to clarify its pathophysiology, there is an urgent need to understand how and if diabetes therapies can control diabetes-related cognitive dysfunction. At the time, although SGLT2 proteins are present in the Central Nervous System (CNS), the SGLT2i effects on cognitive impairments remain partly unknown. In pre-clinical studies, SGLT2i ameliorates cognitive dysfunction in obese and T2DM mice, reducing oxidative stress, neuroinflammation and improving neuronal plasticity and mitochondrial brain pathway. In addition, SGLT2i could bring back mTOR to a physiological state of activation, stopping neurodegenerative diseases' onset or progression. Instead, clinical studies on T2DM-related cognitive dysfunction treated by SGLT2i are much more limited. For these reasons, further studies are needed to better elucidate if SGLT2i therapy can affect T2DM-related cognitive decline. In this scenario, this review aims to summarize the state of knowledge on the role of SGLT2i in T2DM-related cognitive dysfunction and stimulate new clinical trials.

Update on Pathogenesis of Glomerular Hyperfiltration in Early Diabetic Kidney Disease

In the existing stages of diabetic kidney disease (DKD), the first stage of DKD is called the preclinical stage, characterized by glomerular hyperfiltration, an abnormally elevated glomerular filtration rate. Glomerular hyperfiltration is an independent risk factor for accelerated deterioration of renal function and progression of nephropathy, which is associated with a high risk for metabolic and cardiovascular disease. It is imperative to understand hyperfiltration and identify potential treatments to delay DKD progress. This paper summarizes the current mechanisms of hyperfiltration in early DKD. We pay close attention to the effect of glucose reabsorption mediated by sodium-glucose cotransporters and renal growth on hyperfiltration in DKD patients, as well as the mechanisms of nitric oxide and adenosine actions on renal afferent arterioles via tubuloglomerular feedback. Furthermore, we also focus on the contribution of the atrial natriuretic peptide, cyclooxygenase, renin-angiotensin-aldosterone system, and endothelin on hyperfiltration. Proposing potential treatments based on these mechanisms may offer new therapeutic opportunities to reduce the renal burden in this population.

New Insights into the Efficacy of Aspalathin and Other Related Phytochemicals in Type 2 Diabetes-A Review

In the pursuit of bioactive phytochemicals as a therapeutic strategy to manage metabolic risk factors for type 2 diabetes (T2D), aspalathin, C-glucosyl dihydrochalcone from rooibos (Aspalathus linearis), has received much attention, along with its C-glucosyl flavone derivatives and phlorizin, the apple O-glucosyl dihydrochalcone well-known for its antidiabetic properties. We provided context for dietary exposure by highlighting dietary sources, compound stability during processing, bioavailability and microbial biotransformation. The review covered the role of these compounds in attenuating insulin resistance and enhancing glucose metabolism, alleviating gut dysbiosis and associated oxidative stress and inflammation, and hyperuricemia associated with T2D, focusing largely on the literature of the past 5 years. A key focus of this review was on emerging targets in the management of T2D, as highlighted in the recent literature, including enhancing of the insulin receptor and insulin receptor substrate 1 signaling via protein tyrosine phosphatase inhibition, increasing glycolysis with suppression of gluconeogenesis by sirtuin modulation, and reducing renal glucose reabsorption via sodium-glucose co-transporter 2. We conclude that biotransformation in the gut is most likely responsible for enhancing therapeutic effects observed for the C-glycosyl parent compounds, including aspalathin, and that these compounds and their derivatives have the potential to regulate multiple factors associated with the development and progression of T2D.

Crosstalk between Sodium-Glucose Cotransporter Inhibitors and Sodium-Hydrogen Exchanger 1 and 3 in Cardiometabolic Diseases

Abnormality in glucose homeostasis due to hyperglycemia or insulin resistance is the hallmark of type 2 diabetes mellitus (T2DM). These metabolic abnormalities in T2DM lead to cellular dysfunction and the development of diabetic cardiomyopathy leading to heart failure. New antihyperglycemic agents including glucagon-like peptide-1 receptor agonists and the sodium-glucose cotransporter-2 inhibitors (SGLT2i) have been shown to attenuate endothelial dysfunction at the cellular level. In addition, they improved cardiovascular safety by exhibiting cardioprotective effects. The mechanism by which these drugs exert their cardioprotective effects is unknown, although recent studies have shown that cardiovascular homeostasis occurs through the interplay of the sodium-hydrogen exchangers (NHE), specifically NHE1 and NHE3, with SGLT2i. Another theoretical explanation for the cardioprotective effects of SGLT2i is through natriuresis by the kidney. This theory highlights the possible involvement of renal NHE transporters in the management of heart failure. This review outlines the possible mechanisms responsible for causing diabetic cardiomyopathy and discusses the interaction between NHE and SGLT2i in cardiovascular diseases.

The Role of Combined SGLT1/SGLT2 Inhibition in Reducing the Incidence of Stroke and Myocardial Infarction in Patients with Type 2 Diabetes Mellitus

PURPOSE

In patients with type 2 diabetes mellitus (T2DM), both sodium-glucose cotransporter 2 inhibitors (SGLT2is) and glucagon-like peptide receptor agonists (GLP-1 RAs) have demonstrated significant improvements in cardiovascular and kidney outcomes independent of their glycemic benefits. This paper will briefly compare the effect of SGLT2is and GLP-1 RAs to that of the SGLT1/2 inhibitor sotagliflozin on the incidence of myocardial infarction (MI) and stroke in patients with T2DM and further postulate mechanisms to account for these findings.

METHODS AND RESULTS

Thus far, the results from SCORED and SOLOIST (trials studying the SGLT1/2 inhibitor sotagliflozin) suggest that an increase in SGLT1 inhibition when added to SGLT2 inhibition may contribute to reductions in MI and stroke in patients with T2DM. This benefit is beyond what SGLT2is alone can accomplish and at least similar to GLP-1 RAs but with the added benefit of a reduction in hospitalizations and urgent visits for HF. Larger and longer studies are required to confirm the effectiveness of SGLT1/SGLT2 inhibition in reducing MI and stroke in patients with T2DM and elucidate the mechanisms associated with this finding.

CONCLUSIONS

The role of SGLT1/2 inhibition as an addition to GLP-1 RAs in patients with and without T2DM at increased risk for MI and stroke requires further study. Regardless, the finding that a relative increase in SGLT1/2 inhibition reduces the risk of MI and stroke as well as hospitalizations and urgent visits for heart failure could improve quality of life and reduce the healthcare burden associated with T2DM.

One-hour post-load hyperglycemia combined with HbA1c identifies individuals with augmented duodenal levels of sodium/glucose co-transporter 1

AIMS

Individuals with HbA1c-defined prediabetes (HbA1c 5.7-6.4%) and 1-hour post-load plasma glucose (1hPG) ≥ 155 mg/dl have an increased risk to develop type 2 diabetes (T2DM). T2DM is associated with a higher intestinal expression of sodium/glucose co-transporter 1 (SGLT-1) and glucose transporter 2 (GLUT-2). It is currently unsettled whether HbA1c-defined dysglycemic conditions combined to 1hPG ≥ 155 mg/dl are associated with changes in SGLT-1 and GLUT-2 duodenal abundance.

METHODS

SGLT-1 and GLUT-2 protein levels were assessed by western blot on duodenal mucosa biopsies of 57 individuals underwent an upper gastrointestinal endoscopy.

RESULTS

Compared with the normal group (HbA1c < 5.7%), individuals with HbA1c-defined pre-diabetes and diabetes exhibit no significant change in duodenal SGLT-1 abundance. Conversely, duodenal GLUT-2 levels were progressively increased in subjects with prediabetes and diabetes. Stratifying participants according to HbA1c and 1hPG we found that amongst subjects with HbA1c-defined normal or prediabetes condition those having 1hPG ≥ 155 mg/dl displayed higher duodenal levels of SGLT-1 as compared to their counterparts with 1hPG < 155 mg/dl; in contrast to GLUT-2 levels, which were similar between normal and with prediabetes subjects, regardless of 1hPG value.

CONCLUSION

A value of 1hPG ≥ 155 mg/dl may identify a subset of individuals within HbA1c-defined glycemic categories having a higher duodenal abundance of SGLT-1.

Polypharmacology of clinical sodium glucose co-transport protein 2 inhibitors and relationship to suspected adverse drug reactions

Sodium glucose co-transporter 2 inhibitors (SGLT2i) are a promising second-line treatment strategy for type 2 diabetes mellitus (T2DM) with a developing landscape of both beneficial cardio- and nephroprotective properties and emerging adverse drug reactions (ADRs) including diabetic ketoacidosis (DKA), genetic mycotic infections, and amputations among others. A national register study (MHRA Yellow Card, UK) was used to quantify the SGLT2i's suspected ADRs relative to their Rx rate (OpenPrescribing, UK). The polypharmacology profiles of SGLT2i were data-mined (ChEMBL) for the first time. The ADR reports (n = 3629) and prescribing numbers (Rx n = 5,813,325) for each SGLT2i in the United Kingdom (from launch date to the beginning December 2019) were determined. Empagliflozin possesses the most selective SGLT2/SGLT1 inhibition profile at ~2500-fold, ~10-fold more selective than cangliflozin (~260-fold). Canagliflozin was found to also inhibit CYP at clinically achievable concentrations. We find that for overall ADR rates, empagliflozin versus dapagliflozin and empagliflozin versus canagliflozin are statistically significant (χ2 , p < .05), while dapagliflozin versus canagliflozin is not. In terms of overall ADRs, there is a greater relative rate for canagliflozin > dapagliflozin > empagliflozin. For fatalities, there is a greater relative rate for dapagliflozin > canagliflozin > empagliflozin. An organ classification that resulted in a statistically significant difference between SGLT2i was suspected infection/infestation ADRs between empagliflozin and dapagliflozin. Our findings at this stage of SGLT2i usage in the United Kingdom suggest that empagliflozin, the most selective SGLT2i, had the lowest suspected ADR incident rate (relative to prescribing) and in all reported classes of ADRs identified including infections, amputations, and DKA.

Molecular Docking and Simulation Studies of Antidiabetic Agents Devised from Hypoglycemic Polypeptide-P of Momordica charantia

Diabetes mellitus termed as metabolic disorder is a collection of interlinked diseases and mainly body's inability to manage glucose level which leads to cardiovascular diseases, renal failure, neurological disorders, and many others. The drugs contemporarily used for diabetes have many inevitable side effects, and many of them have become less responsive to this multifactorial disorder. Momordica charantia commonly known as bitter gourd has many bioactive compounds with antidiabetic properties. The current study was designed to use computational methods to discover the best antidiabetic peptides devised from hypoglycemic polypeptide-P of M. charantia. The binding affinity and interaction patterns of peptides were evaluated against four receptor proteins (i.e., as agonists of insulin receptor and inhibitors of sodium-glucose cotransporter 1, dipeptidyl peptidase-IV, and glucose transporter 2) using molecular docking approach. A total of thirty-seven peptides were docked against these receptors. Out of which, top five peptides against each receptor were shortlisted based on their S-scores and binding affinities. Finally, the eight best ligands (i.e., LIVA, TSEP, EKAI, LKHA, EALF, VAEK, DFGAS, and EPGGGG) were selected as these ligands strictly followed Lipinski's rule of five and exhibited good ADMET profiling. One peptide EPGGGG showed activity towards insulin and SGLT1 receptor proteins. The top complex for both these targets was subjected to 50 ns of molecular dynamics simulations and MM-GBSA binding energy test that concluded both complexes as highly stable, and the intermolecular interactions were dominated by van der Waals and electrostatic energies. Overall, the selected ligands strongly fulfilled the drug-like evaluation criterion and proved to have good antidiabetic properties.

Changes in Glycolytic Pathway in SARS-COV 2 Infection and Their Importance in Understanding the Severity of COVID-19

COVID-19 is an infectious disease caused by Coronavirus 2 (SARS-CoV-2) that may lead to a severe acute respiratory syndrome. Such syndrome is thought to be related, at least in part, to a dysregulation of the immune system which involves three main components: hyperactivity of the innate immune system; decreased production of type 1 Interferons (IFN) by SARS-CoV-2-infected cells, namely respiratory epithelial cells and macrophages; and decreased numbers of both CD4+ and particularly CD8+ T cells. Herein, we describe how excessive activation of the innate immune system and the need for viral replication in several cells of the infected organism promote significant alterations in cells' energy metabolism (glucose metabolism), which may underlie the poor prognosis of the disease in severe situations. When activated, cells of the innate immune system reprogram their metabolism, and increase glucose uptake to ensure secretion of pro-inflammatory cytokines. Changes in glucose metabolism are also observed in pulmonary epithelial cells, contributing to dysregulation of cytokine synthesis and inflammation of the pulmonary epithelium. Controlling hyperglycolysis in critically ill patients may help to reduce the exaggerated production of pro-inflammatory cytokines and optimise the actions of the adaptive immune system. In this review, we suggest that the administration of non-toxic concentrations of 2-deoxy-D-glucose, the use of GLUT 1 inhibitors, of antioxidants such as vitamin C in high doses, as well as the administration of N-acetylcysteine in high doses, may be useful complementary therapeutic strategies for these patients, as suggested by some clinical trials and/ or reports. Overall, understanding changes in the glycolytic pathway associated with COVID-19 infection can help to find new forms of treatment for this disease.

Emergence of SGLT2 Inhibitors as Powerful Antioxidants in Human Diseases

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of oral glucose-lowering agents. Apart from their glucose-lowering effects, large clinical trials assessing certain SGLT2 inhibitors have revealed cardiac and renal protective effects in non-diabetic patients. These excellent outcomes motivated scientists and clinical professionals to revisit their underlying mechanisms. In addition to the heart and kidney, redox homeostasis is crucial in several human diseases, including liver diseases, neural disorders, and cancers, with accumulating preclinical studies demonstrating the therapeutic benefits of SGLT2 inhibitors. In the present review, we aimed to update recent advances in the antioxidant roles of SGLT2 inhibitors in common but debilitating human diseases. We anticipate that this review will guide new research directions and novel therapeutic strategies for diabetes, cardiovascular diseases, nephropathies, liver diseases, neural disorders, and cancers in the era of SGLT2 inhibitors.

Mechanisms of Glucose Absorption in the Small Intestine in Health and Metabolic Diseases and Their Role in Appetite Regulation

The worldwide prevalence of metabolic diseases such as obesity, metabolic syndrome and type 2 diabetes shows an upward trend in recent decades. A characteristic feature of these diseases is hyperglycemia which can be associated with hyperphagia. Absorption of glucose in the small intestine physiologically contributes to the regulation of blood glucose levels, and hence, appears as a putative target for treatment of hyperglycemia. In fact, recent progress in understanding the molecular and cellular mechanisms of glucose absorption in the gut and its reabsorption in the kidney helped to develop a new strategy of diabetes treatment. Changes in blood glucose levels are also involved in regulation of appetite, suggesting that glucose absorption may be relevant to hyperphagia in metabolic diseases. In this review we discuss the mechanisms of glucose absorption in the small intestine in physiological conditions and their alterations in metabolic diseases as well as their relevance to the regulation of appetite. The key role of SGLT1 transporter in intestinal glucose absorption in both physiological conditions and in diabetes was clearly established. We conclude that although inhibition of small intestinal glucose absorption represents a valuable target for the treatment of hyperglycemia, it is not always suitable for the treatment of hyperphagia. In fact, independent regulation of glucose absorption and appetite requires a more complex approach for the treatment of metabolic diseases.

Insights Into the Results of Sotagliflozin Cardiovascular Outcome Trials: Is Dual Inhibition the Cherry on the Cake of Cardiorenal Protection?

Sotagliflozin is a dual sodium-glucose co-transporter (SGLT) 2 inhibitor, manifesting a 20-fold higher inhibitory activity for SGLT2 than for SGLT1. Differences in SGLT2 over SGLT1 selectivity of the available agents have been proposed to relate to variability in efficacy and safety characteristics. In contrast to other SGLT2 inhibitors, the cardiorenal effects of sotagliflozin in type 2 diabetes had not been explored until recently, when the results of SOLOIST-WHF (focusing on heart failure [HF] outcomes) and SCORED (focusing on renal outcomes) were published. In SOLOIST-WHF, sotagliflozin reduced the risk of the primary composite outcome of cardiovascular (CV) death and hospitalizations and urgent visits for HF. The findings showed that the risk reduction was consistent in people with reduced but also in those with preserved ejection fraction (EF). In SCORED, sotagliflozin significantly reduced the primary end point of CV deaths, hospitalizations for HF, and urgent visits for HF. A reduction in glycated hemoglobin was evident even in participants with estimated glomerular filtration rate values below 30 mL/min/1.73 m². SCORED is also the first trial to illustrate the benefits of the class across the full range of albuminuria. Moreover, the endpoint of stroke was significantly reduced by 34% in the sotagliflozin compared with the placebo group. The findings of the two studies provide novel insights into the clinical utility of SGLT2 inhibitors, particularly with respect to the early initiation in stable HF, the benefits in HF with preserved EF, the glucose-lowering efficacy in people with severe renal impairment and their potential to improve atherosclerotic vascular disease, including stroke, outcomes.

Pleiotropic Effects of Sodium-Glucose Cotransporter-2 Inhibitors: Renoprotective Mechanisms beyond Glycemic Control

Diabetes mellitus is a major cause of chronic kidney disease and end-stage renal disease. However, the management of chronic kidney disease, particularly diabetes, requires vast improvements. Recently, sodium-glucose cotransporter-2 (SGLT2) inhibitors, originally developed for the treatment of diabetes, have been shown to protect against kidney injury via glycemic control, as well as various other mechanisms, including blood pressure and hemodynamic regulation, protection from lipotoxicity, and uric acid control. As such, regulation of these mechanisms is recommended as an effective multidisciplinary approach for the treatment of diabetic patients with kidney disease. Thus, SGLT2 inhibitors are expected to become key drugs for treating diabetic kidney disease. This review summarizes the recent clinical evidence pertaining to SGLT2 inhibitors as well as the mechanisms underlying their renoprotective effects. Hence, the information contained herein will advance the current understanding regarding the pleiotropic effects of SGLT2 inhibitors, while promoting future research in the field.

Fructose malabsorption: causes, diagnosis and treatment

This review intends to act as an overview of fructose malabsorption (FM) and its role in the aetiology of diseases including, but not limited to, irritable bowel syndrome (IBS) and infantile colic and the relationship between fructose absorption and the propagation of some cancers. IBS results in a variety of symptoms including stomach pains, cramps and bloating. Patients can be categorised into two groups, depending on whether the patients’ experiences either constipation (IBS-C) or diarrhoea (IBS-D). FM has been proposed as a potential cause of IBS-D and other diseases, such as infantile colic. However, our knowledge of FM is limited by our understanding of the biochemistry related to the absorption of fructose in the small intestine and FM’s relationship with small intestinal bacterial overgrowth. It is important to consider the dietary effects on FM and most importantly, the quantity of excess free fructose consumed. The diagnosis of FM is difficult and often requires indirect means that may result in false positives. Current treatments of FM include dietary intervention, such as low fermentable oligo-, di-, monosaccharides and polyols diets and enzymatic treatments, such as the use of xylose isomerase. More research is needed to accurately diagnose and effectively treat FM. This review is designed with the goal of providing a detailed outline of the issues regarding the causes, diagnosis and treatment of FM.

Altered intestinal epithelial nutrient transport: an underappreciated factor in obesity modulated by diet and microbiota

Dietary nutrients absorbed in the proximal small intestine and assimilated in different tissues have a profound effect on overall energy homeostasis, determined by a balance between body's energy intake and expenditure. In obesity, altered intestinal absorption and consequently tissue assimilation of nutrients may disturb the energy balance leading to metabolic abnormalities at the cellular level. The absorption of nutrients such as sugars, amino acids and fatty acids released from food digestion require high-capacity transporter proteins expressed in the intestinal epithelial absorptive cells. Furthermore, nutrient sensing by specific transporters/receptors expressed in the epithelial enteroendocrine cells triggers release of gut hormones involved in regulating energy homeostasis via their effects on appetite and food intake. Therefore, the intestinal epithelial cells play a pivotal role in the pathophysiology of obesity and associated complications. Over the past decade, gut microbiota has emerged as a key factor contributing to obesity via its effects on digestion and absorption of nutrients in the small intestine, and energy harvest from dietary fiber, undigested component of food, in the large intestine. Various mechanisms of microbiota effects on obesity have been implicated. However, the impact of obesity-associated microbiota on the intestinal nutrient transporters needs extensive investigation. This review marshals the limited studies addressing the altered structure and function of the gut epithelium in obesity with special emphasis on nutrient transporters and role of diet and microbiota. The review also discusses the thoughts and controversies and research gaps in this field.

Intestinal SGLT1 as a therapeutic target in COVID-19-related diabetes: A "two-edged sword" hypothesis

Emerging data are linking coronavirus disease 2019 (COVID‐19) with an increased risk of developing new‐onset diabetes. The gut has been so far out of the frame of the discussion on the pathophysiology of COVID‐19‐induced diabetes, with the pancreas, liver, and adipose tissue being under the spotlight of medical research. Sodium‐glucose co‐transporters (SGLT) 1 represent important regulators of glucose absorption, expressed in the small intestine where they mediate almost all sodium‐dependent glucose uptake. Similar to what happens in diabetes and other viral infections, SGLT1 upregulation could result in increased intestinal glucose absorption and subsequently promote the development of hyperglycaemia in COVID‐19. Considering the above, the question whether dual SGLT (1 and 2) inhibition could contribute to improved outcomes in such cases sounds challenging, deserving further evaluation. Future studies need to clarify whether putative benefits of dual SGLT inhibition in COVID‐19 outweigh potential risks, particularly with respect to drug‐induced euglycaemic diabetic ketoacidosis, gastrointestinal side effects, and compromised host response to pathogens.

Shift of conventional paradigm of heart failure treatment: from angiotensin receptor neprilysin inhibitor to sodium-glucose co-transporter 2 inhibitors?

Current clinical guidelines for heart failure (HF) contain a brand new therapeutic strategy for HF with reduced ejection fraction (HFrEF), which is based on neurohumoral modulation through the use of angiotensin receptor neprilysin inhibitors. There is a large body of evidence for the fact that sodium-glucose co-transporter 2 inhibitors may significantly improve all-cause mortality, cardiovascular mortality and hospitalization for HF in patients with HFrEF who received renin-angiotensin system blockers including angiotensin receptor neprilysin inhibitors, β-blockers and mineralocorticoid receptor antagonists. The review discusses that sodium-glucose co-transporter 2 inhibitors have a wide spectrum of favorable molecular effects and contribute to tissue protection, improving survival in HFrEF patients.

Canagliflozin: metabolic, cardiovascular and renal protection

Patients with Type 2 Diabetes (T2D) are at risk of developing macrovascular (cardiac, cerebrovascular, peripheral arterial disease) and microvascular (nephropathy, neuropathy, retinopathy) complications. Glycemic control improves only microvascular outcomes. However, some SGLT-2 inhibitors and GLP1-R agonists have proven beneficial in macrovascular conditions. Canagliflozin is an SGLT2 inhibitor that provides sustained reductions in HbA1c, blood pressure and weight. Remarkably, as CANVAS program and CREDENCE trial demonstrated, canagliflozin promotes significant reductions in the frequency of atherosclerotic cardiovascular events, hospitalizations for heart failure and renal outcomes. In addition, real-world studies have confirmed the results of clinical trials in clinical practice. Therefore, canagliflozin should be considered a first-line therapy in the management of T2D patients in order to reduce both micro- and macrovascular complications.

Sodium-Glucose Co-Transporter 2 (SGLT2) Inhibitors: Are They All the Same? A Narrative Review of Cardiovascular Outcome Trials

Clinically important improvements in cardiovascular risk factors and adverse cardiovascular, heart failure and renal outcomes have been observed in numerous cardiovascular outcome trials (CVOTs) investigating the use of sodium-glucose co-transporter 2 (SGLT2) inhibitors over the last 5 years. However, differences in study outcomes between the various SGLT2 inhibitor CVOTs are often challenging to interpret because of differences in the study design, participant characteristics and primary outcomes of the various trials. In clinical practice, this frequently challenges the clinician when choosing between the different SGLT2 inhibitors for a patient with type 2 diabetes and various cardiovascular or renal comorbidities. Discussion around the choice of SGLT2 inhibitor has been again revived by the recent publication of results from the VERTIS-CV, EMPEROR-reduced and DAPA-CKD trials investigating cardiovascular, heart failure and renal outcomes associated with various SGLT2 inhibitors.This narrative review gives an overview of the mechanism of action and differences in the underlying pharmacology of the various SGLT2 inhibitors and discusses the key cardiovascular, heart failure and renal outcomes from completed CVOTs for SGLT2 inhibitors. Discussion highlights important differences in the study design and participant characteristics which limit the comparison of trials and medications within this drug class.

Intestinal sodium/glucose cotransporter 3 expression is epithelial and downregulated in obesity

AIM

We aimed to determine whether the sodium/glucose cotransporter family member SGLT3, a proposed glucose sensor, is expressed in the intestine and/or kidney, and if its expression is altered in mouse models of obesity and in humans before and after weight-loss surgery.

MAIN METHODS

We used in-situ hybridization and quantitative PCR to determine whether the Sglt3 isoforms 3a and 3b were expressed in the intestine and kidney of C57, leptin-deficient ob/ob, and diabetic BTBR ob/ob mice. Western blotting and immunohistochemistry were also used to assess SGLT3 protein levels in jejunal biopsies from obese patients before and after weight-loss Roux-en-Y gastric bypass surgery (RYGB), and in lean healthy controls.

KEY FINDINGS

Sglt3a/3b mRNA was detected in the small intestine (duodenum, jejunum and ileum), but not in the large intestine or kidneys of mice. Both isoforms were detected in epithelial cells (confirmed using intestinal organoids). Expression of Sglt3a/3b mRNA in duodenum and jejunum was significantly lower in ob/ob and BTBR ob/ob mice than in normal-weight littermates. Jejunal SGLT3 protein levels in aged obese patients before RYGB were lower than in lean individuals, but substantially upregulated 6 months post-RYGB.

SIGNIFICANCE

Our study shows that Sglt3a/3b is expressed primarily in epithelial cells of the small intestine in mice. Furthermore, we observed an association between intestinal mRNA Sglt3a/3b expression and obesity in mice, and between jejunal SGLT3 protein levels and obesity in humans. Further studies are required to determine the possible role of SGLT3 in obesity.

The nephrological perspective on SGLT-2 inhibitors in type 1 diabetes

Prevalence of type 1 diabetes mellitus (T1DM) is globally continuously increasing. T1DM is accompanied by a high risk of developing cardiovascular and renal comorbidities and is one of the leading causes of end-stage renal disease (ESRD). However, current therapeutic approaches for chronic and/or diabetic kidney disease (CKD/DKD) existed for a long time, and offer room for improvement, particularly in T1DM. In 2019, the European Medicines Agency (EMA) approved a first sodium/glucose co-transporter 2 inhibitor (SGLT-2i) and a first dual SGLT-1/-2i to improve glycaemic control, as an adjunctive treatment to insulin in persons with T1DM and a body mass index ≥27 kg/m². Of note, SGLT-1/2is and SGLT-2is are not approved by the Food and Drug Administration (FDA) as an adjunct treatment in T1DM, nor approved for the treatment of CKD or DKD by EMA and FDA. SGLT is have shown to mediate different renoprotective effects in type 2 diabetes mellitus in corresponding cardiovascular and renal outcome trials. First efficacy trials offer insights into potential positive effects on renal function and kidney disease of SGLTis in T1DM. This review summarizes and discusses latest available data on SGLT inhibition and provides an update on the nephrological perspective on SGLTis, specifically in T1DM.

Tubular effects of sodium-glucose cotransporter 2 inhibitors: intended and unintended consequences

PURPOSE OF REVIEW

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are antihyperglycemic drugs that act by inhibiting renal sodium-glucose cotransport. Here we present new insights into 'off target', or indirect, effects of SGLT2 inhibitors.

RECENT FINDINGS

SGLT2 inhibition causes an acute increase in urinary glucose excretion. In addition to lowering blood glucose, there are several other effects that contribute to the overall beneficial renal and cardiovascular effects. Reabsorption of about 66% of sodium is accomplished in the proximal tubule and dependent on the sodium-hydrogen exchanger isoform 3 (NHE3). SGLT2 colocalizes with NHE3, and high glucose levels reduce NHE3 activity. The proximal tubule is also responsible for the majority of phosphate (Pi) reabsorption. SGLT2 inhibition is associated with increases in plasma Pi, fibroblast growth factor 23 and parathyroid hormone levels in nondiabetics and type 2 diabetes mellitus. Studies in humans identified a urate-lowering effect by SGLT2 inhibition which is possibly mediated by urate transporter 1 (URAT1) and/or glucose transporter member 9 in the proximal tubule. Of note, magnesium levels were also found to increase under SGLT2 inhibition, an effect that was preserved in nondiabetic patients with hypomagnesemia.

SUMMARY

Cardiorenal effects of SGLT2 inhibition might involve, in addition to direct effects on glucose homeostasis, effects on NHE3, phosphate, urate, and magnesium homeostasis.

5,5-Difluoro- and 5-Fluoro-5-methyl-hexose-based C-Glucosides as potent and orally bioavailable SGLT1 and SGLT2 dual inhibitors

(2S,3R,4R,5S,6R)-2-Aryl-5,5-difluoro-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4-diols and (2S,3R,4R,5S,6R)-2-aryl-5-fluoro-5-methyl-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4-diols were discovered as dual inhibitors of sodium glucose co-transporter proteins (e.g. SGLT1 and SGLT2) through rational drug design, efficient synthesis, and in vitro and in vivo evaluation. Compound 6g demonstrated potent dual inhibitory activities (IC₅₀ = 96 nM for SGLT1 and IC₅₀ = 1.3 nM for SGLT2). It showed robust inhibition of blood glucose excursion in an oral glucose tolerance test (OGTT) in Sprague Dawley (SD) rats when dosed at both 1 mg/kg and 10 mg/kg orally. It also demonstrated postprandial glucose control in db/db mice when dosed orally at 10 mg/kg.

Comparison of mechanisms and transferability of outcomes of SGLT2 inhibition between type 1 and type 2 diabetes

Diabetes mellitus (DM) is a major chronic disease with ever-increasing prevalence and a variety of serious complications for persons with DM, such as cardiovascular and/or renal complications. New glucose-lowering therapies like DPP-4 inhibitors, GLP-1 receptor agonists, and SGLT-2 inhibitors have undergone cardiovascular outcome trials (CVOTs) for type 2 diabetes (T2DM), as by the guidance of the FDA. However, CVOTs for type 1 diabetes (T1DM) are generally lacking. Both, persons with T1DM and T2DM, are burdened with a high incidence of cardiovascular and renal disease such as atherosclerotic cardiovascular disease (ASCVD) and diabetic kidney disease (DKD). Although pathologies of the two types of diabetes cannot be compared, similar mechanisms and risk factors like sex, hyperglycaemia, hypertension, endothelial damage and (background) inflammation have been identified in the development of CVD and DKD in T1DM and T2DM. Recent CVOTs in T2DM demonstrated that SGLT-2 inhibitors, besides exerting a glucose-lowering effect, have beneficial effects on cardiovascular and renal mechanisms. These mechanisms are reviewed in detail in this manuscript and evaluated for possible transferability to, and thus efficacy in, T1DM. Our review of current literature suggests that SGLT-2 inhibitors have cardioprotective benefits beyond their glucose-lowering effects. As this mainly has been observed in CVOTs in T2DM, further investigation in the adjunctive therapy for type 1 diabetes is suggested.

Clinical Benefit of Cardiorenal Effects of Sodium-Glucose Cotransporter 2 Inhibitors: JACC State-of-the-Art Review

Changes in the regulatory guidelines by the U.S. Food and Drug Administration and the European Medical Agency requiring large-scale trials that study the cardiovascular safety of new glucose-lowering drugs have improved our understanding of type 2 diabetes mellitus. Unexpectedly, these trials demonstrated that sodium-glucose cotransporter 2 inhibitors reduce adverse cardiovascular outcomes. This second part of this 2-part review summarizes the findings of recent clinical trials and their clinical implications and describes ongoing trials and future areas of research.

Effects of Sodium-Glucose Cotransporter Inhibitor/Glucagon-Like Peptide-1 Receptor Agonist Add-On to Insulin Therapy on Glucose Homeostasis and Body Weight in Patients With Type 1 Diabetes: A Network Meta-Analysis

Many patients with type 1 diabetes (T1D) do not achieve the glycemic target goal with insulin treatment. In this study, we aimed to evaluate the efficacy and safety of add-on to insulin therapy in patients with T1D. We conducted direct and indirect network meta-analyses using Bayesian models and ranked hypoglycemic agents via mixed treatment comparison, using data from the CENTRAL, MEDLINE, EMBASE, and Science Citation Index Expanded databases. Randomized controlled trials (RCTs) involving patients with T1D treated with insulin and add-on metformin or sodium-glucose cotransporter inhibitors or glucagon-like peptide-1 receptor agonists from January 1970 to September 2019 were included in this study. Twenty-three RCTs with 5,151 subjects were divided into the following groups: insulin alone, insulin+metformin, insulin+canagliflozin, insulin+dapagliflozin, insulin+empagliflozin, insulin+sotagliflozin, insulin+liraglutide, and insulin+exenatide. HbA1c level in the insulin+sotagliflozin group was significantly lower than that in the insulin alone group (mean difference: -0.43, 95% credible interval: -0.62 to -0.23). Total daily insulin dose in the insulin+sotagliflozin group was significantly lower than that in the insulin alone group. Compared with that in the insulin alone group, body weight in the groups treated with insulin+add-on canagliflozin, sotagliflozin, and exenatide was significantly decreased by 4.5, 2.8, and 5.1 kg, respectively. Hypoglycemic episodes did not differ among the groups. In patients with T1D, insulin+sotagliflozin decreased the HbA1c level, daily insulin dose, and body weight without hypoglycemia compared with insulin monotherapy. Insulin+canagliflozin or insulin+exenatide was effective in reducing body weight compared with insulin alone. In conclusion, sotagliflozin treatment decreased not only the HbA1c levels and insulin dose but also the body weight without causing hypoglycemia in patients with T1D. Treatment with canagliflozin and exenatide effectively reduced body weight in patients with T1D. However, ketoacidosis associated with the use of SGLT inhibitors should be considered in these patients. Thus, our results suggest that sotagliflozin has a high probability of being ranked first as an adjunctive therapy to insulin in patients with T1D.

Effects of sodium-glucose cotransporter inhibitors on cardiorenal and metabolic systems: Latest perspectives from the outcome trials

Diabetes mellitus is strongly linked to high risk of cardiovascular and renal disorders. Diabetes management requires coordinated efforts to manage multiple cardiometabolic risk factors. Diabetes mellitus is also associated with poor outcome in patients after cardiovascular events and renal complications. However, whether specific antidiabetic agents are safer and more efficacious than other drugs for preventing and treating these cardiometabolic and renal diseases is debated. To date, results are available from 12 cardiovascular outcome trials focusing mainly on major adverse cardiovascular events and renal outcomes with new antidiabetic agents (4 with dipeptidyl peptidase-4 inhibitors, 3 with sodium-glucose cotransporter-2 (SGLT2) inhibitors, and 5 with glucagon-like peptide-1 analogues). Among them, the studies of SGLT2 inhibitors showed favourable results both for cardiovascular and renal outcomes. It would be crucial to dissect the effects of SGLT2 inhibitors on cardiorenal and metabolic systems, to determine whether it is better to prescribe SGLT2 inhibitors compared with other antidiabetic medications.

Sodium-Glucose Cotransporter-2 (SGLT2) Inhibitors: A Clinician's Guide

This comprehensive review covers the historical background, physiology, application in type 2 diabetes, novel uses, cardiovascular benefits, side effects and contraindications of sodium-glucose cotransporter-2 (SGLT2) inhibitors. SGLT2 inhibitors are an insulin-independent class of oral antihyperglycemic medication that clinicians use in the treatment of type 2 diabetes. Multiple landmark clinical trials support the effectiveness of SGLT2 inhibitors in reducing blood glucose levels, but it is important to understand when to properly utilize them. SGLT2 inhibitors are the most beneficial as an adjunct medication in addition to metformin in patients with a history of cardiovascular or renal disease who need further hemoglobin A1c reduction. The novel mechanism of action also demands clinicians be aware of the side effects not typically experienced with other oral antihyperglycemic drugs, such as genital tract infections, lower leg amputations, electrolyte disturbances and bone fractures. On top of their benefits in type 2 diabetes, novel uses for SGLT2 inhibitors are being uncovered. Diabetic patients with non-alcoholic fatty liver disease, who are at an increased risk of cirrhosis and hepatocellular carcinoma, experience a clinically significant reduction in serum alanine aminotransferase levels. SGLT2 inhibitors are also effective at lowering body weight in obese individuals and decreasing systolic blood pressure. Dual SGLT1/SGLT2 inhibitors are currently being investigated as possibly the first oral medication for type 1 diabetes.