Effects of sodium glucose cotransporter 2 inhibitors on mineral metabolism in type 2 diabetes mellitus

The associations of sodium-glucose cotransporter-2 inhibitors versus dipeptidyl peptidase-4 inhibitors as add-on to metformin with fracture risk in patients with type 2 diabetes mellitus

AIM

To investigate whether sodium-glucose cotransporter-2 (SGLT2) inhibitor use as compared to dipeptidyl peptidase-4 (DPP-4) inhibitor use as add-on to metformin is associated with the risk of any fracture or major osteoporotic fractures (MOFs).

METHODS

A cohort study using the Clinical Practice Research Datalink (CPRD) Aurum database was conducted. All patients aged 18 years and older with a first-ever prescription for a DPP-4 inhibitor or an SGLT2 inhibitor as add-on to metformin between January 1, 2013 and June 30, 2020 were selected. Patients starting with SGLT2 inhibitors were matched (up to 1:3) on propensity scores to patients starting with DPP-4 inhibitors. Propensity scores were calculated based on sex, age, body mass index, comorbidities, comedication and lifestyle factors. Cox proportional hazard models were used to estimate the risk of fracture with SGLT2 inhibitor use as compared to DPP-4 inhibitor use.

RESULTS

A total of 13 807 SGLT2 inhibitor users (age 55.4 ± 10.6 years, 36.7% female) were included in this study, matched with 28 524 DPP-4 inhibitor users (age 55.4 ± 8.0 years, 36.4% female). The risk of any fracture with current SGLT2 inhibitor use was similar compared with current DPP-4 inhibitor use (adjusted hazard ratio [aHR] 1.09, 95% confidence interval [CI] 0.91-1.31), as was the risk of MOFs (aHR 0.89, 95% CI 0.64-1.22) and the risk of fractures at any of the individual MOF sites. Additionally, no association was found with duration of SGLT2 inhibitor use (longest duration >811 days) for any of the individual SGLT2 inhibitor agents, or after stratification by sex and age.

CONCLUSION

Use of SGLT2 inhibitors was not associated with the risk of any fracture, MOFs or fracture at the individual MOF sites when compared to DPP-4 inhibitor use.

Cardiovascular Calcification Heterogeneity in Chronic Kidney Disease

Patients with chronic kidney disease (CKD) exhibit tremendously elevated risk for cardiovascular disease, particularly ischemic heart disease, due to premature vascular and cardiac aging and accelerated ectopic calcification. The presence of cardiovascular calcification associates with increased risk in patients with CKD. Disturbed mineral homeostasis and diverse comorbidities in these patients drive increased systemic cardiovascular calcification in different manifestations with diverse clinical consequences, like plaque instability, vessel stiffening, and aortic stenosis. This review outlines the heterogeneity in calcification patterning, including mineral type and location and potential implications on clinical outcomes. The advent of therapeutics currently in clinical trials may reduce CKD-associated morbidity. Development of therapeutics for cardiovascular calcification begins with the premise that less mineral is better. While restoring diseased tissues to a noncalcified homeostasis remains the ultimate goal, in some cases, calcific mineral may play a protective role, such as in atherosclerotic plaques. Therefore, developing treatments for ectopic calcification may require a nuanced approach that considers individual patient risk factors. Here, we discuss the most common cardiac and vascular calcification pathologies observed in CKD, how mineral in these tissues affects function, and the potential outcomes and considerations for therapeutic strategies that seek to disrupt the nucleation and growth of mineral. Finally, we discuss future patient-specific considerations for treating cardiac and vascular calcification in patients with CKD-a population in need of anticalcification therapies.

Mouse Models with SGLT2 Mutations: Toward Understanding the Role of SGLT2 beyond Glucose Reabsorption

The sodium–glucose cotransporter 2 (SGLT2) mainly carries out glucose reabsorption in the kidney. Familial renal glycosuria, which is a mutation of SGLT2, is known to excrete glucose in the urine, but blood glucose levels are almost normal. Therefore, SGLT2 inhibitors are attracting attention as a new therapeutic drug for diabetes, which is increasing worldwide. In fact, SGLT2 inhibitors not only suppress hyperglycemia but also reduce renal, heart, and cardiovascular diseases. However, whether long-term SGLT2 inhibition is completely harmless requires further investigation. In this context, mice with mutations in SGLT2 have been generated and detailed studies are being conducted, e.g., the SGLT2−/− mouse, Sweet Pee mouse, Jimbee mouse, and SAMP10-ΔSglt2 mouse. Biological changes associated with SGLT2 mutations have been reported in these model mice, suggesting that SGLT2 is not only responsible for sugar reabsorption but is also related to other functions, such as bone metabolism, longevity, and cognitive functions. In this review, we present the characteristics of these mutant mice. Moreover, because the relationship between diabetes and Alzheimer’s disease has been discussed, we examined the relationship between changes in glucose homeostasis and the amyloid precursor protein in SGLT2 mutant mice.

Acquired Disorders of Hypomagnesemia

Magnesium disorders are common in clinical practice and when present can manifest clinically as cardiovascular, neuromuscular, or other organ dysfunction. Hypomagnesemia is far more common than hypermagnesemia, which is largely seen in patients with reduced glomerular filtration rates receiving magnesium-containing medications. In addition to inherited disorders of magnesium handling, hypomagnesemia is also seen with excessive gastrointestinal or renal losses and due to medications such as amphotericin B, aminoglycosides, and cisplatin. Laboratory assessment of body magnesium stores largely relies on the measurement of serum magnesium levels that are a poor proxy for total body stores but does correlate with the development of symptoms. Replacement of magnesium can be challenging, with oral replacement strategies being generally more effective at slowly replacing body stores but intravenous replacement being more effective at treating the more life-threatening and severe cases of hypomagnesemia. We conducted a thorough review of the literature using PubMed (1970-2022) and the search terms magnesium, hypomagnesemia, drugs, medications, treatment, and therapy. In the absence of clear data on optimal management of hypomagnesemia, we have made recommendations on magnesium replacement based on our clinical experience.

Kidney-Protective Effects of SGLT2 Inhibitors

The sodium-glucose cotransporter 2 (SGLT2) inhibitors have become an integral part of clinical practice guidelines to slow the progression of CKD in patients with and without diabetes mellitus. Although initially developed as antihyperglycemic drugs, their effect on the kidney is multifactorial resulting from profuse glycosuria and natriuresis consequent to their primary site of action. Hemodynamic and metabolic changes ensue that mediate kidney-protective effects, including ( 1 ) decreased workload of proximal tubular cells and prevention of aberrant increases in glycolysis, contributing to a decreased risk of AKI; ( 2 ) lowering of intraglomerular pressure by activating tubular glomerular feedback and reductions in BP and tissue sodium content; ( 3 ) initiation of nutrient-sensing pathways reminiscent of starvation activating ketogenesis, increased autophagy, and restoration of carbon flow through the mitochondria without production of reactive oxygen species; ( 4 ) body weight loss without a reduction in basal metabolic rate due to increases in nonshivering thermogenesis; and ( 5 ) favorable changes in quantity and characteristics of perirenal fat leading to decreased release of adipokines, which adversely affect the glomerular capillary and signal increased sympathetic outflow. Additionally, these drugs stimulate phosphate and magnesium reabsorption and increase uric acid excretion. Familiarity with kidney-specific mechanisms of action, potential changes in kidney function, and/or alterations in electrolytes and volume status, which are induced by these widely prescribed drugs, will facilitate usage in the patients for whom they are indicated.

The Eucalcemic Patient With Elevated Parathyroid Hormone Levels

Primary hyperparathyroidism (PHPT) is classically characterized by hypercalcemia with elevated or inappropriately normal parathyroid hormone (PTH) levels. Elevated PTH levels in the presence of normal calcium levels are not infrequently found during the evaluation of metabolic bone disorders or kidney stone disease. This can be caused by secondary hyperparathyroidism (SHPT) or normocalcemic primary hyperparathyroidism (NPHPT). NPHPT is due to autonomous parathyroid function whereas SHPT is caused by a physiologic stimulation to PTH secretion. Many medical conditions and medications can contribute to SHPT, and differentiation between SHPT and NPHPT may be difficult. Cases are presented to illustrate examples. In this paper, we review the distinction between SHPT and NPHPT as well as end organ effects of NPHPT and outcomes of surgery in NPHPT. We suggest that the diagnosis of NPHPT be made only after careful exclusion of causes of SHPT and consideration of medications that can increase PTH secretion. Further, we advise a conservative approach to surgery in NPHPT.

Unfavorable effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors on the skeletal system of nondiabetic rats

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of antidiabetic drugs, acting by inhibiting the reabsorption of glucose in the kidneys. They turned out to improve cardiovascular and renal outcomes not only in patients with type 2 diabetes but also in nondiabetic patients. At present, they are more and more widely used in patients without diabetes. Since there were concerns that SGLT2 inhibitors may increase fracture risk in diabetes, the aim of the study was to examine the effect of dapagliflozin and canagliflozin on the musculoskeletal system of nondiabetic, healthy rats. The experiments were carried out on mature female rats, divided into the control rats and rats treated with dapagliflozin (1.4 mg/kg p.o.) or canagliflozin (4.2 mg/kg p.o.) for 4 weeks. Serum bone turnover markers, skeletal muscle strength and mass, bone mass, density, histomorphometric parameters and mechanical properties were determined. Administration of the drugs did not affect the skeletal muscle mass and strength. There was no effect on serum bone turnover markers, and bone mass and composition. However, administration of both drugs resulted in disorders of cancellous bone microarchitecture and worsening of bone mechanical properties. In conclusion, both SGLT2 inhibitors unfavorably affected the skeletal system of healthy rats.

Use of sodium-glucose co-transporter 2 inhibitors, changes in body mass index and risk of fracture: A population-based cohort study

AIMS

Sodium-glucose co-transporter-2 (SGLT-2) inhibitor-induced weight loss might play a role in the debated elevated fracture risk with these agents. The aim of the current study was to investigate the association between SGLT-2 inhibitor use, changes in body mass index (BMI) and fracture risk.

METHODS

A retrospective cohort study was conducted using data from the UK Clinical Practice Research Datalink (CPRD) GOLD (2013-2018). The study population (N = 34,960) consisted of adults with diabetes initiating a sulphonylurea or SGLT-2 inhibitor. Cox proportional hazards models estimated hazard ratios (HRs) for major osteoporotic fracture with SGLT-2 inhibitor use versus sulphonylurea use, stratified by change in BMI, average daily dose and cumulative dose. Analyses were adjusted for age, sex, lifestyle variables, comorbidities, and concomitant drug use.

RESULTS

SGLT-2 inhibitor use was not associated with an increased fracture risk compared to sulphonylurea use (adjusted HR 1.19; 95% confidence interval (CI): 0.80-1.79). This finding remained consistent after stratification by BMI change. However, the highest cumulative dose category was associated with an increased fracture risk (adjusted HR: 2.10, 95 %CI: 1.11-3.99).

CONCLUSION

SGLT-2 inhibitor use was not associated with increased osteoporotic fracture risk, irrespective of change in BMI. However, a high cumulative dose could be an important risk factor.

Changes in Serum Intact Fibroblast Growth Factor 23 Concentrations From Midlife to Late Life and Their Predictors in the Community: The ARIC Study

Objective

To investigate longitudinal changes in the blood concentration of fibroblast growth factor 23 (FGF23) from midlife to late life and their major predictors in the general population.

Patients and Methods

In 14,444 participants of the Atherosclerosis Risk in Communities Study, we analyzed the association of 31,095 measurements of serum intact FGF23 with age using data from 3 visits (visit 2 [N=13,460; mean age, 57 years]; visit 3 [N=12,323; mean age, 60 years]; and visit 5 [N=6122; mean age, 76 years]) and a linear mixed-effects model. Among 5804 participants who had FGF23 measurements at both visits 3 and 5, we explored predictors of FGF23 change from midlife to late life using linear regression models. Prespecified risk factors were estimated glomerular filtration rate, body mass index, ever smoking, ever drinker, diabetes, hypertension, history of cardiovascular disease, total cholesterol, and high-density lipoprotein cholesterol.

Results

Median FGF23 concentrations were 41.9 pg/mL (interquartile interval [IQI], 33.9 to 51.8 pg/mL) at visit 2, 38.3 pg/mL (IQI, 30.6 to 48.3 pg/mL) at visit 3, and 55.0 pg/mL (IQI, 44.4 to 70.3 pg/mL) at visit 5. A linear mixed-effects model showed that the association of FGF23 with age was nonlinear, with a slight decline or no change in age 45-60 years and a monotonic increase in age greater than or equal to 65 years (FGF23, +10 to 15 pg/mL per 10 years of age). In a multivariable linear regression model, significantly greater increases in FGF23 were noted, with midlife estimated glomerular filtration rate less than 60 mL/min per 1.73 m2 vs more than or equal to 60 mL/min per 1.73 m2 (ΔFGF23, +4.4 pg/mL [95% CI, 0.9 to 8.0]), diabetes vs no diabetes (ΔFGF23, +6.2 pg/mL [95% CI, 4.1 to 8.3]), and hypertension vs no hypertension (ΔFGF23, +4.1 pg/mL [95% CI, 2.7 to 5.4]).

Conclusion

FGF23 did not show any major changes in midlife but increased linearly in late life. Reduced kidney function, diabetes, and hypertension were robustly associated with a greater increase in FGF23. Further investigations are needed to understand the potential mechanisms linking these conditions to an increase in FGF23 concentrations.

Assessment of Proximal Tubular Function by Tubular Maximum Phosphate Reabsorption Capacity in Heart Failure

BACKGROUND AND OBJECTIVES

The estimated glomerular filtration rate (eGFR) is a crucial parameter in heart failure. Much less is known about the importance of tubular function. We addressed the effect of tubular maximum phosphate reabsorption capacity (TmP/GFR), a parameter of proximal tubular function, in patients with heart failure.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We established TmP/GFR (Bijvoet formula) in 2085 patients with heart failure and studied its association with deterioration of kidney function (>25% eGFR decrease from baseline) and plasma neutrophil gelatinase-associated lipocalin (NGAL) doubling (baseline to 9 months) using logistic regression analysis and clinical outcomes using Cox proportional hazards regression. Additionally, we evaluated the effect of sodium-glucose transport protein 2 (SGLT2) inhibition by empagliflozin on tubular maximum phosphate reabsorption capacity in 78 patients with acute heart failure using analysis of covariance.

RESULTS

Low TmP/GFR (<0.80 mmol/L) was observed in 1392 (67%) and 21 (27%) patients. Patients with lower TmP/GFR had more advanced heart failure, lower eGFR, and higher levels of tubular damage markers. The main determinant of lower TmP/GFR was higher fractional excretion of urea (P<0.001). Lower TmP/GFR was independently associated with higher risk of plasma NGAL doubling (odds ratio, 2.20; 95% confidence interval, 1.05 to 4.66; P=0.04) but not with deterioration of kidney function. Lower TmP/GFR was associated with higher risk of all-cause mortality (hazard ratio, 2.80; 95% confidence interval, 1.37 to 5.73; P=0.005), heart failure hospitalization (hazard ratio, 2.29; 95% confidence interval, 1.08 to 4.88; P=0.03), and their combination (hazard ratio, 1.89; 95% confidence interval, 1.07 to 3.36; P=0.03) after multivariable adjustment. Empagliflozin significantly increased TmP/GFR compared with placebo after 1 day (P=0.004) but not after adjustment for eGFR change.

CONCLUSIONS

TmP/GFR, a measure of proximal tubular function, is frequently reduced in heart failure, especially in patients with more advanced heart failure. Lower TmP/GFR is furthermore associated with future risk of plasma NGAL doubling and worse clinical outcomes, independent of glomerular function.

Phosphate and fibroblast growth factor 23 in diabetes

Diabetes is associated with a strongly elevated risk of cardiovascular disease, which is even more pronounced in patients with diabetic nephropathy. Currently available guideline-based efforts to correct traditional risk factors are only partly able to attenuate this risk, underlining the urge to identify novel treatment targets. Emerging data point towards a role for disturbances in phosphate metabolism in diabetes. In this review, we discuss the role of phosphate and the phosphate-regulating hormone fibroblast growth factor 23 (FGF23) in diabetes. We address deregulations of phosphate metabolism in patients with diabetes, including diabetic ketoacidosis. Moreover, we discuss potential adverse consequences of these deregulations, including the role of deregulated phosphate and glucose as drivers of vascular calcification propensity. Finally, we highlight potential treatment options to correct abnormalities in phosphate and FGF23. While further studies are needed to more precisely assess their clinical impact, deregulations in phosphate and FGF23 are promising potential target in diabetes and diabetic nephropathy.

Effects of ipragliflozin versus metformin in combination with sitagliptin on bone and muscle in Japanese patients with type 2 diabetes mellitus: Subanalysis of a prospective, randomized, controlled study (PRIME-V study)

AIMS/INTRODUCTION

Recent randomized clinical trials have suggested that sodium-glucose cotransporter 2 inhibitors might reduce cardiovascular events and heart failure, and have renal protective effects. Despite these remarkable benefits, the effects of sodium-glucose cotransporter 2 inhibitors on bone and muscle are unclear.

MATERIALS AND METHODS

A subanalysis of a randomized controlled study was carried out to evaluate the effects of the sodium-glucose cotransporter 2 inhibitor, ipragliflozin, versus metformin on bone and muscle in Japanese patients with type 2 diabetes mellitus (baseline body mass index ≥22 kg/m2 and hemoglobin A1c 7-10%) who were already receiving sitagliptin. These patients were randomly administered ipragliflozin 50 mg or metformin 1,000-1,500 mg daily. The effects of these medications on the bone formation marker, bone alkali phosphatase; the bone resorption marker, tartrate-resistant acid phosphatase 5b (TRACP-5b); handgrip strength; abdominal cross-sectional muscle area; and bone density of the fourth lumbar vertebra were evaluated.

RESULTS

After 24 weeks of treatment, the changes in bone density of the fourth lumbar vertebra, handgrip strength and abdominal cross-sectional muscle area were not significantly different between the two groups. However, TRACP-5b levels increased in patients treated with ipragliflozin compared with patients treated with metformin (median 11.94 vs -10.30%, P < 0.0001), showing that ipragliflozin can promote bone resorption.

CONCLUSIONS

There were no adverse effects on bone or muscle when sitagliptin was used in combination with either ipragliflozin or metformin. However, ipragliflozin combination increased the levels of TRACP-5b. A long-term study is required to further understand the effects of this TRACP-5b increase caused by ipragliflozin.

Canagliflozin, an SGLT2 inhibitor, corrects glycemic dysregulation in TallyHO model of T2D but only partially prevents bone deficits

Higher fracture risk in type 2 diabetes (T2D) is attributed to disease-specific deficits in micro-structural and material properties of bone, although the primary cause is not yet established. The TallyHO (TH) mouse is a polygenic model of early-onset T2D and obesity analogous to adolescent-onset T2D in humans. Due to incomplete penetrance of the phenotype, ~25% of male TH mice never develop hyperglycemia, providing a strain-matched, non-diabetic control. Utilizing this model of T2D, we examined the impact of glucose-lowering therapy with canagliflozin (CANA) on diabetic bone. Male TH mice with or without hyperglycemia (High BG, Low BG) were monitored from ~8 to 20 weeks of age, and compared to age-matched, male, TH mice treated with CANA from ~8 to 20 weeks of age. At 20 weeks, untreated TH mice with high BG [High BG: 687 ± 106 mg/dL] exhibited lower body mass, decrements in cortical bone of the femur (decreased cross-sectional area and thickness; increased porosity) and in trabecular bone of the femur metaphysis and L6 vertebra (decreased bone volume fraction, thickness, and tissue mineral density), as well as decrements in cortical and vertebral bone strength (decreased yield force and ultimate force) when compared to untreated TH mice with low BG [Low BG: 290 ± 98 mg/dL; p < 0.0001]. CANA treatment was metabolically advantageous, normalizing body mass, BG and HbA1c to values comparable to the Low BG group. With drug-induced glycemic improvement, cortical area and thickness were significantly higher in the CANA than in the High BG group, but deficits in strength persisted with lower yield force and yield stress (partially independent of bone geometry) in the CANA group. Additionally, CANA only partially prevented the T2D-related loss in trabecular bone volume fraction. Taken together, these findings suggest that the ability of CANA to lower glucose and normalized glycemic control ameliorates diabetic bone disease but not fully.

Potential Safety Issues with Use of Sodium-Glucose Cotransporter 2 Inhibitors, Particularly in People with Type 2 Diabetes and Chronic Kidney Disease

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a major advance in the fields of diabetology, nephrology, and cardiology. The cardiovascular and renal benefits of SGLT2 inhibitors are likely largely independent of their glycaemic effects, and this understanding is central to the use of these agents in the high-risk population of people with type 2 diabetes and chronic kidney disease. There are a number of potential safety issues associated with the use of SGLT2 inhibitors. These include the rare but serious risks of diabetic ketoacidosis and necrotising fasciitis of the perineum. The data regarding a possibly increased risk of lower limb amputation and fracture with SGLT2 inhibitor therapy are conflicting. This article aims to explore the potential safety issues associated with the use of SGLT2 inhibitors, with a particular focus on the safety of these drugs in people with type 2 diabetes and chronic kidney disease. We discuss strategies that clinicians can implement to minimise the risk of adverse effects including diabetic ketoacidosis and volume depletion. Risk mitigation strategies with respect to SGLT2 inhibitor-associated diabetic ketoacidosis are of particular importance during the current coronavirus disease 2019 (COVID-19) pandemic.

Sodium-glucose cotransporter type 2 inhibitors for the treatment of type 2 diabetes mellitus

The management of type 2 diabetes mellitus (T2DM) is becoming increasingly complex. Sodium-glucose cotransporter type 2 inhibitors (SGLT2is) are the newest antidiabetic agents for T2DM. By targeting the kidney, they have a unique mechanism of action, which results in enhanced glucosuria, osmotic diuresis and natriuresis, thereby improving glucose control with a limited risk of hypoglycaemia and exerting additional positive effects such as weight loss and the lowering of blood pressure. Several outcome studies with canagliflozin, dapagliflozin or empagliflozin reported a statistically significant reduction in major cardiovascular events, hospitalization for heart failure and progression to advanced renal disease in patients with T2DM who have established atherosclerotic cardiovascular disease, several cardiovascular risk factors, albuminuric mild to moderate chronic kidney disease or heart failure. Current guidelines proposed a new paradigm in the management of T2DM, with a preferential place for SGLT2is, after metformin, in patients with atherosclerotic cardiovascular disease, heart failure and progressive kidney disease. Ongoing trials might extend the therapeutic potential of SGLT2is in patients with, but also without, T2DM. This Review provides an update of the current knowledge on SGLT2is, moving from their use as glucose-lowering medications to their new positioning as cardiovascular and renal protective agents.

Fibroblast Growth Factor 23 and Adverse Clinical Outcomes in Type 2 Diabetes: a Bitter-Sweet Symphony

PURPOSE OF REVIEW

Fibroblast growth factor 23 (FGF23) is a key phosphate-regulating hormone that has been associated with adverse outcomes in patients with chronic kidney disease (CKD). Emerging data suggest that FGF23 plays a specific role in type 2 diabetes, partly independent of kidney function. We aimed to summarize current literature on the associations between FGF23 and outcomes in patients with type 2 diabetes with or without CKD.

RECENT FINDINGS

Several cohort studies have shown strong associations between plasma FGF23 and cardiovascular outcomes in diabetic CKD. Moreover, recent data suggest that FGF23 are elevated and may also be a risk factor for cardiovascular disease and mortality in type 2 diabetes patients without CKD, although the magnitude of the association is smaller than in CKD patients. Diabetes-related factors may influence plasma FGF23 levels, and a higher FGF23 levels seem to contribute to a higher cardiovascular and mortality risk in patients with type 2 diabetes. Although this risk may be relevant in diabetic individuals with preserved kidney function, it is strongly accentuated in diabetic nephropathy. Future studies should clarify if FGF23 is merely a disease severity marker or a contributor to adverse outcomes in type 2 diabetes and establish if antidiabetic medication can modify FGF23 levels.

Sodium-coupled glucose transport, the SLC5 family, and therapeutically relevant inhibitors: from molecular discovery to clinical application

Sodium glucose transporters (SGLTs) belong to the mammalian solute carrier family SLC5. This family includes 12 different members in human that mediate the transport of sugars, vitamins, amino acids, or smaller organic ions such as choline. The SLC5 family belongs to the sodium symporter family (SSS), which encompasses transporters from all kingdoms of life. It furthermore shares similarity to the structural fold of the APC (amino acid-polyamine-organocation) transporter family. Three decades after the first molecular identification of the intestinal Na⁺-glucose cotransporter SGLT1 by expression cloning, many new discoveries have evolved, from mechanistic analysis to molecular genetics, structural biology, drug discovery, and clinical applications. All of these advances have greatly influenced physiology and medicine. While SGLT1 is essential for fast absorption of glucose and galactose in the intestine, the expression of SGLT2 is largely confined to the early part of the kidney proximal tubules, where it reabsorbs the bulk part of filtered glucose. SGLT2 has been successfully exploited by the pharmaceutical industry to develop effective new drugs for the treatment of diabetic patients. These SGLT2 inhibitors, termed gliflozins, also exhibit favorable nephroprotective effects and likely also cardioprotective effects. In addition, given the recent finding that SGLT2 is also expressed in tumors of pancreas and prostate and in glioblastoma, this opens the door to potential new therapeutic strategies for cancer treatment by specifically targeting SGLT2. Likewise, further discoveries related to the functional association of other SGLTs of the SLC5 family to human pathologies will open the door to potential new therapeutic strategies. We furthermore hope that the herein summarized information about the physiological roles of SGLTs and the therapeutic benefits of the gliflozins will be useful for our readers to better understand the molecular basis of the beneficial effects of these inhibitors, also in the context of the tubuloglomerular feedback (TGF), and the renin-angiotensin system (RAS). The detailed mechanisms underlying the clinical benefits of SGLT2 inhibition by gliflozins still warrant further investigation that may serve as a basis for future drug development.