Role of Glycosuria in SGLT2 Inhibitor-Induced Cardiorenal Protection: A Mechanistic Analysis of the CREDENCE Trial.

SGLT2 inhibitors have been shown to provide pronounced reductions in cardiorenal outcomes, including cardiovascular death, heart failure, and renal failure. The mechanisms underlying these benefits remain uncertain. We hypothesized that the effects could be attributed to the elevated glycosuria induced by these drugs. Urine concentrations of glucose, creatinine, and ketones were measured at baseline and after 1 year of treatment with either placebo or canagliflozin 100 mg/day, in approximately 2,600 individuals from the Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) trial (enrolling patients with type 2 diabetes, chronic kidney disease (CKD), and albuminuria). Associations between glycosuria and the primary composite end point from CREDENCE, and secondary outcomes were assessed using Cox proportional hazards models. Canagliflozin treatment increased fractional urinary glucose excretion (± SD) from 3 ± 9% at baseline to 30 ± 26% at year 1 (vs. 5 ± 19% with placebo; P < 0.001). Patients in the canagliflozin arm and in the top quartile of urine glucose to creatinine ratio at year 1 were significantly protected for the primary end point (hazard ratio [HR] 0.42; 95% CI 0.30-0.61); similar results were seen for cases of hospitalized heart failure (HR 0.45; 95% CI 0.27-0.73) and all-cause death (HR 0.56; 95% CI 0.39-0.80). These associations persisted when adjustments were made for multiple conventional risk factors. Among patients with type 2 diabetes and CKD treated with canagliflozin, individuals with the highest glycosuria levels had the strongest protection against multiple cardiorenal outcomes.

Renal and Cardiovascular Metabolic Impact Caused by Ketogenesis of the SGLT2 Inhibitors.

Sodium-glucose cotransporter type 2 inhibitors (SGLT2i) are glycosuric drugs that were originally developed for the treatment of type 2 diabetes mellitus (T2DM). There is a hypothesis that SGLT2i are drugs that are capable of increasing ketone bodies and free fatty acids. The idea is that they could serve as the necessary fuel, instead of glucose, for the purposes of cardiac muscle requirements and could explain antihypertensive effects, which are independent of renal function. The adult heart, under normal conditions, consumes around 60% to 90% of the cardiac energy that is derived from the oxidation of free fatty acids. In addition, a small proportion also comes from other available substrates. In order to meet energy demands with respect to achieving adequate cardiac function, the heart is known to possess metabolic flexibility. This allows it to switch between different available substrates in order to obtain the energy molecule adenosine triphosphate (ATP), thereby rendering it highly adaptive. It must be noted that oxidative phosphorylation in aerobic organisms is the main source of ATP, which is a result of reduced cofactors. These cofactors include nicotine adenine dinucleotide (NADH) and flavin adenine dinucleotide (FADH2), which are the result of electron transfer and are used as the enzymatic cofactors that are involved in the respiratory chain. When there is an excessive increase in energy nutrients-such as glucose and fatty acids-which occur in the absence of a parallel increase in demand, a state of nutrient surplus (which is better known as an excess in supply) is created. The use of SGLT2i at the renal level has also been shown to generate beneficial metabolic alterations, which are obtained by reducing the glucotoxicity that is induced by glycosuria. Together with the reduction in perivisceral fat in various organs, such alterations also lead to the use of free fatty acids in the initial stages of the affected heart. Subsequently, this results in an increase in production with respect to ketoacids, which are a more available energy fuel at the cellular level. In addition, even though their mechanism is not fully understood, their vast benefits render them of incredible importance for the purposes of further research.

Bittersweet: infective complications of drug-induced glycosuria in patients with diabetes mellitus on SGLT2-inhibitors: two case reports.

BACKGROUND: Sodium-glucose co-transporter 2 (SGLT2) inhibitors are novel hypoglycemic agents which reduce reabsorption of glucose at the renal proximal tubule, resulting in significant glycosuria and increased risk of genital mycotic infections (GMI). These infections are typically not severe as reported in large systematic reviews and meta-analyses of the medications. These reviews have also demonstrated significant cardiovascular benefits through other mechanisms of action, making them attractive options for the management of Type 2 diabetes mellitus (T2DM). We present two cases with underlying abnormalities of the urogenital tract in which the GMI were complicated and necessitated cessation of the SGLT2 inhibitor. CASE PRESENTATIONS: Both cases are patients with T2DM on empagliflozin, an SGLT2 inhibitor. The first case is a 64 year old man with Candida albicans balanitis and candidemia who was found to have an obstructing renal calculus and prostatic abscess requiring operative management. The second case describes a 72 year old man with Candida glabrata candidemia who was found to have prostatomegaly, balanitis xerotica obliterans with significant urethral stricture and bladder diverticulae. His treatment was more complex due to fluconazole resistance and concerns about urinary tract penetration of other antifungals. Both patients recovered following prolonged courses of antifungal therapy and in both cases the SGLT2 inhibitor was ceased. CONCLUSIONS: Despite their cardiovascular benefits, SGLT2 inhibitors can be associated with complicated fungal infections including candidemia and patients with anatomical abnormalities of the urogenital tract may be more susceptible to these infections as demonstrated in these cases. Clinicians should be aware of their mechanism of action and associated risk of infection and prior to prescription, assessment of urogenital anatomical abnormalities should be performed to identify patients who may be at risk of complicated infection.

Corazón y riñón en la diabetes: efectos de los glucosúricos / The heart and kidney in diabetes: Heart and kidney in diabetes

El riñón del diabético presenta un exceso de expresión y actividad del trasportador SGLT2 del túbulo proximal. Esta situación aumenta la reabsorción renal de Na y glucosa, y reduce la oferta distal de los mismos. Además de los efectos metabólicos sobre el medio interno de este exceso de glucosa reabsorbida, el túbulo renal se ve sometido a un estrés glicosilativo capaz de activar localmente tanto apoptosis como inflamasoma. El resultado es la pérdida progresiva de unidades nefronales, la activación de la transición epitelio mensangial y del depósito de colágeno. Se produce la activación de la señalización de insulina por la vía de la MAP kinasa y la resistencia a los efectos metabólicos de la insulina. Simultáneamente se superpone una vasodilatación aferente por la hiperglucemia, una inhibición del feed-back túbulo-glomerular por la reducción en la oferta distal de fluido, la desdiferenciación de los podocitos y la reducción en su número, estos últimos efectos debidos a la resistencia a la insulina. El resultado es un daño renal autoalimentado, con hiperpresión intraglomerular, desdiferenciación podocitaria, apoptosis tubular y activación local y a distancia del inflamasoma. Todos estos efectos son susceptibles de corregirse total o parcialmente al inhibir el trasporte de glucosa a través de los SGLT2

The diabetic kidney presents excess expression and activity of the SGLT2 transporter of the proximal tubule. This situation increases the renal reabsorption of Na and glucose and reduces their distal supply. In addition to the metabolic effects on the internal environment of this excess reabsorbed glucose, the renal tubule is subjected to glycosylated stress capable of locally activating both apoptosis and inflammasome. The result is a progressive loss of nephron units, activation of transition of mesangial epithelium and collagen deposition. Activation of insulin signalling by the MAP kinase pathway and resistance to the metabolic effects of insulin take place. This is simultaneously combined with afferent vasodilation due to hyperglycaemia, tubuloglomerular feedback inhibition due to reduced distal fluid supply, podocyte dedifferentiation and reduction in their number, the latter effects being due to insulin resistance. The result is self-feeding renal damage, with intraglomerular hyper-pressure, podocyte dedifferentiation, tubular apoptosis, and local and distant activation of inflammasome. All these effects are susceptible to be totally or partially corrected by inhibiting glucose transport via the SGLT transporters

Amelioration of diabetic nephropathy by SGLT2 inhibitors independent of its glucose-lowering effect: A possible role of SGLT2 in mesangial cells.

Several clinical studies have shown the beneficial effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors on diabetic nephropathy. The underlying mechanisms are not fully understood. We found that administration of canagliflozin at a low dose (0.01 mg/kg/day) did not affect either blood glucose levels or glycosuria, but it improved albuminuria and mesangial expansion in db/db mice to a similar extent as at a high dose (3.0 mg/kg/day) that lowered blood glucose levels. This indicated the existence of a tubular SGLT2-independent reno-protective mechanism. Here we focused on the potential role of SGLT2 in mesangial cells (MCs). Western blot analysis revealed the expression of SGLT2 in cultured mouse MCs. Exposure of MCs to high glucose levels for 72 h significantly increased the expression of SGLT2. Canagliflozin or ipragliflozin (both 100 nM) treatment inhibited glucose consumption in the medium under high-glucose conditions but not under normal-glucose conditions. Furthermore, canagliflozin inhibited high-glucose-induced activation of the protein kinase C (PKC)-NAD(P)H oxidase pathway and increases in reactive oxygen species (ROS) production. Thus, the inhibition of mesangial SGLT2 may cause an inhibition of PKC activation and ROS overproduction in diabetic nephropathy, and this may at least in part account for the reno-protective effect of SGLT2 inhibitors.

Diuretic Effects of Sodium Glucose Cotransporter 2 Inhibitors and Their Influence on the Renin-Angiotensin System.

The renin-angiotensin system (RAS) plays an important role in regulating body fluids and blood pressure. However, inappropriate activation of the RAS contributes to the pathogenesis of cardiovascular and renal diseases. Recently, sodium glucose cotransporter 2 (SGLT2) inhibitors have been used as anti-diabetic agents. SGLT2 inhibitors induce glycosuria and improve hyperglycemia by inhibiting urinary reabsorption of glucose. However, in the early stages of treatment, these inhibitors frequently cause polyuria and natriuresis, which potentially activate the RAS. Nevertheless, the effects of SGLT2 inhibitors on RAS activity are not straightforward. Available data indicate that treatment with SGLT2 inhibitors transiently activates the systemic RAS in type 2 diabetic patients, but not the intrarenal RAS. In this review article, we summarize current evidence of the diuretic effects of SGLT2 inhibitors and their influence on RAS activity.

Hormonal, Metabolic and Hemodynamic Adaptations to Glycosuria in Type 2 Diabetes Patients Treated with Sodium-Glucose Co-Transporter Inhibitors.

Background & Introduction: The advent of the sodium-glucose cotransporter-2 inhibitors [SGLT-2i] provides an additional tool to combat diabetes and complications. The use of SGLT-2i leads to effective and durable glycemic control with important reductions in body weight/fat and blood pressure. These agents may delay beta-cell deterioration and improve tissue insulin sensitivity, which might slow the progression of the disease. Methods & Results: In response to glycosuria, a compensatory rise in endogenous glucose production, sustained by a decrease in plasma insulin with an increase in glucagon has been described. Other possible mediators have been implicated and preliminary findings suggest that a sympathoadrenal discharge and/or rapid elevation in circulating substrates (i.e., fatty acids) or some yet unidentified humoral factors may have a role in a renal-hepatic inter-organ relationship. A possible contribution of enhanced renal gluconeogenesis to glucose entry into the systemic circulation has not yet been ruled out. Additionally, tissue glucose utilization decreases, whereas adipose tissue lipolysis is stimulated and, there is a switch to lipid oxidation with the formation of ketone bodies; the risk for keto-acidosis may limit the use of SGLT-2i. These metabolic adaptations are part of a counter-regulatory response to avoid hypoglycemia and, as a result, limit the SGLT-2i therapeutic efficacy. Recent trials revealed important cardiovascular [CV] beneficial effects of SGLT-2i drugs when used in T2DM patients with CV disease. Although the underlying mechanisms are not fully understood, there appears to be "class effect". Changes in hemodynamics and electrolyte/body fluid distribution are likely involved, but there is no evidence for anti-atherosclerotic effects. Conclusion: It is anticipated that, by providing durable diabetes control and reducing CV morbidity and mortality, the SGLT-2i class of drugs is destined to become a priority choice in diabetes management.

Effect of Dapagliflozin Treatment on Fluid and Electrolyte Balance in Diabetic Rats.

AIM: This study evaluates the effect of dapagliflozin, a SGLT2 inhibitor, on fluid or electrolyte balance and its effect on urea transporter-A1 (UT-A1), aquaporin-2 (AQP2) and Na-K-2Cl cotransporter (NKCC2) protein abundance in diabetic rats. METHODS: Diabetes mellitus (DM) was induced by injection of streptozotocin into the tail vein. Serum Na+, K+, Cl- concentration, urine Na+, K+, Cl- excretion, blood glucose, urine glucose excretion, urine volume, urine osmolality and urine urea excretion were analyzed after the administration of dapagliflozin. UT-A1, AQP2 and NKCC2 proteins were detected by western blot. RESULTS: Dapagliflozin treatment decreased blood glucose concentration by 38% at day 7 and by 47% at day 14 and increased the urinary glucose excretion rate compared with the untreated diabetic animals. Increased 24-hour urine volume, decreased urine osmolality and hyponatremia, hypokalemia and hypochloremia observed in diabetic rats were attenuated by dapagliflozin treatment. Western blot analysis showed that UT-A1, AQP2 and NKCC2 proteins are upregulated in DM rats over control rats; dapagliflozin treatment results in a further increase in inner medulla tip UT-A1 protein abundance by 42% at day 7 and by 46% at day 14, but it did not affect the DM-induced upregulation of AQP2 and NKCC2 proteins. CONCLUSION: Dapagliflozin treatment augmented the compensatory changes in medullary transport proteins in DM. These changes would tend to conserve solute and water even with persistent glycosuria. Therefore, diabetic rats treated with dapagliflozin have a mild osmotic diuresis compared to nondiabetic animals, but this does not result in an electrolyte disorder or significant volume depletion.

Implicaciones hemodinámicas y renales de los inhibidores del cotransportador sodio-glucosa tipo 2 en el contexto de la diabetes mellitus tipo 2 / Hemodynamic and renal implications of sodium-glucose cotransporter-2 inhibitors in type 2 diabetes mellitus

Durante la diabetes mellitus tipo 2 se produce un aumento en la expresión del transportador proximal de glucosa SGLT2. Este aumento indebido de la recuperación de glucosa filtrada desde la orina hacia el túbulo proximal y, posteriormente, hacia el torrente sanguíneo tiene 3 repercusiones directas sobre el pronóstico del paciente con diabetes mellitus tipo 2: a) aumento de la carga diaria de glucosa al elevar el umbral de reabsorción. Como consecuencia aumentan los requerimientos de antidiabéticos orales y de insulina. Este aumento es progresivo a lo largo de la enfermedad y va a la par con el aumento de masa renal (hipertrofia renal); b) la mayor reabsorción de glucosa hace que la glucosuria sea menor de la correspondiente al valor de glucemia, disminuyendo el estímulo sobre el «feed-back» tubuloglomerular de la nefrona distal. Como resultado, no se contrarresta la vasodilatación glomerular causada por la hiperglucemia, perpetuándose la hiperfiltración glomerular, y c) el exceso de glucosa transportado a la célula del túbulo proximal modifica el estado redox de esta, aumentando la producción local de productos con capacidad glucosilativa y activando la producción local de mediadores proliferativos proinflamatorios y profibróticos. Estos mediadores son responsables del daño directo por radicales libres a la célula tubular proximal, del aumento de expresión de SGLT2, del aumento de producción de colágeno IV y de matriz extracelular, y de la activación de monocitosmacrófagos con capacidad lesiva endotelial. La utilización de inhibidores del transporte proximal de glucosa SGLT2 no solo reduce la reinyección de la glucosa ya filtrada desde la orina hacia la sangre, mejorando el control metabólico de la diabetes, sino que además restaura el «feed-back» tubuloglomerular al aumentar la glucosuria y el flujo urinario distal. Pero el efecto más notable se debe a la inhibición de la entrada de glucosa en la célula tubular proximal. La glucosuria es tóxica para el riñón: lo es para las células capaces de transportar glucosa, es decir, las células proximales dotadas de SGLT2. En modelos animales, al inhibir SGLT2 se reduce la producción local de radicales de oxígeno, disminuye la formación de matriz mesangial y de colágeno IV, hay menor infiltración glomerular por células inflamatorias y se reduce la arteriosclerosis dependiente de monocito-macrófago. En clínica humana, los iSGLT2 han mostrado su capacidad para reducir el daño renal y el riesgo cardiovascular de los pacientes con diabetes mellitus tipo 2 (AU)

In DM2, there is increased expression of the proximal glucose transporter SGLT2. The increased glucose reabsorption from the urine to the proximal tubule and subsequently to the bloodstream, has three direct effects on the prognosis of patients with DM2: a) it increases the daily glucose load by raising the renal threshold for glucose, thus augmenting requirements for oral antidiabetics and insulin. This progressive increase occurs throughout the course of the disease and in parallel with the increase in renal mass (renal hypertrophy); b) because of the greater glucose reabsorption, glycosuria is lower than the level corresponding to glycaemia, decreasing the stimulus on the tubuloglomerular feedback system of the distal nephron. As a result, the glomerular vasodilation caused by hyperglycaemia is not arrested, maintaining glomerular hyperfiltration, and c) the excess glucose transported to the proximal tubular cells modifies their redox status, increasing local production of glycosylating products and activating local production of proinflammatory and profibrotic proliferative mediators. These mediators are responsible for the direct free radical damage to proximal tubular cells, for increased SGLT2 expression, increased production of collagen IV and extracellular matrix, and activation of monocyte/macrophages able to cause endothelial injury. The use of SGLT2 inhibitors not only reduces the reabsorption of glucose from the glomerular filtrate back into the circulationthus improving metabolic control in diabetesbut also restores tubuloglomerular feedback by increasing glycosuria and distal urinary flow. However, the most notable effect is due to inhibition of glucose entry to the proximal tubular cells. Glycosuria is toxic to the kidney: it harms glucosetransporting cells, that is, the proximal cells, which contain SGLT2. In animal models, SGLT2 inhibition reduces local production of oxygen-free radicals, the formation of mesangial matrix and collagen IV, glomerular infiltration by inflammatory cells and monocyte/macrophage-dependent arteriosclerosis. In humans, SGLT2 have a demonstrated ability to reduce renal injury and cardiovascular risk in patients with type 2 diabetes mellitus (AU)

8-Aminoguanosine and 8-Aminoguanine Exert Diuretic, Natriuretic, Glucosuric, and Antihypertensive Activity.

In vivo, guanine moieties in DNA, RNA, guanine nucleotides, or guanosine or guanine per se can undergo nitration (for example, by peroxynitrite) or hydroxylation (for example, by superoxide anion) on position 8 of the purine ring. Subsequent catabolism of these modified biomolecules leads to the production of a diverse group of 8-nitro, 8-amino, and 8-hydroxy guanosine and guanine compounds. Indeed, studies suggest the in vivo existence of 8-nitroguanosine, 8-nitroguanine, 8-aminoguanosine, 8-aminoguanine, 8-hydroxyguanosine, 8-hydroxy-2'-deoxyguanosine, and 8-hydroxyguanine. Since a multitude of these compounds exist in vivo, and since the renal effects of 8-substituted guanosine and guanine compounds are entirely unknown, we examined the effects of guanosine, guanine, 8-nitroguanosine, 8-nitroguanine, 8-hydroxyguanosine, 8-hydroxyguanine, 8-hydroxy-2'-deoxyguanosine, 8-aminoguanosine, and 8-aminoguanine (33.5 µmol/kg/min; intravenous infusion for 115 minutes) on excretion of sodium, potassium, and glucose in rats. Guanosine, 8-nitroguanosine, and 8-hydroxy-2'-deoxyguanosine had minimal natriuretic activity. Guanine, 8-nitroguanine, 8-hydroxyguanosine, and 8-hydroxyguanine had moderate natriuretic activity (increased sodium excretion by 9.4-, 7.8-, 7.1-, and 8.6-fold, respectively). In comparison with all other compounds, 8-aminoguanosine and 8-aminoguanine were highly efficacious and increased sodium excretion by 26.6- and 17.2-fold, respectively, exceeding that of a matched dose of amiloride (13.6-fold increase). 8-Aminoguanosine and 8-aminoguanine also increased glucose excretion by 12.1- and 12.2-fold, respectively, and decreased potassium excretion by 69.1 and 71.0%, respectively. Long-term radiotelemetry studies demonstrated that oral 8-aminoguanosine and 8-aminoguanine (5 mg/kg/day) suppressed deoxycorticosterone/salt-induced hypertension. These experiments demonstrate that some naturally occurring 8-substitued guanosine and guanine compounds, particularly 8-aminoguanosine and 8-aminoguanine, are potent and efficacious potassium-sparing diuretics/natriuretics that may represent a novel class of antihypertensive diuretics.

Effect of canagliflozin and metformin on cortical neurotransmitters in a diabetic rat model.

BACKGROUND: The rapid economic development in the Arabian Gulf has resulted in lifestyle changes that have increased the prevalence of obesity and type 2 diabetes, with the greatest increases observed in Kuwait. Dyslipidemia and diabetes are risk factors for disruptions in cortical neurotransmitter homeostasis. This study investigated the effect of the antidiabetic medications canagliflozin (CAN) and metformin (MET) on the levels of cortical neurotransmitters in a diabetic rat model. MATERIALS AND METHODS: The rats were assigned to the control (C) group, the diabetic group that did not receive treatment (D) or the diabetic group treated with either CAN (10 mg/kg) or MET (100 mg/kg) for 2 or 4 weeks. Blood and urine glucose levels and cortical acetylcholinesterase (AChE) activity were assayed, and amino acid and monoamine levels were measured using HPLC. RESULTS: The diabetic group exhibited a significant increase in AChE activity and a decrease in monoamine and amino acid neurotransmitter levels. In the CAN group, AChE was significantly lower than that in the D and D + MET groups after 2 weeks of treatment. In addition, a significant increase in some cortical monoamines and amino acids was observed in the D + MET and D + CAN groups compared with the D group. Histopathological analysis revealed the presence of severe focal hemorrhage, neuronal degeneration, and cerebral blood vessel congestion, with gliosis in the cerebrum of rats in the D group. The CAN-treated group exhibited severe cerebral blood vessel congestion after 2 weeks of treatment and focal gliosis in the cerebrum after 4 weeks of treatment. Focal gliosis in the cerebrum of rats in the MET-treated group was observed after 2 and 4 weeks of treatment. CONCLUSIONS: We conclude that the effect of CAN and MET on neurotransmitters is potentially mediated by their antihyperglycemic and antihyperlipidemic effects. In addition, the effects of CAN on neurotransmitters might be associated with its receptor activity, and the effect of MET on neurotransmitters might be associated with cerebral metabolism.

Sodium-Glucose Linked Cotransporter-2 Inhibition Does Not Attenuate Disease Progression in the Rat Remnant Kidney Model of Chronic Kidney Disease.

Pharmacological inhibition of the proximal tubular sodium-glucose linked cotransporter-2 (SGLT2) leads to glycosuria in both diabetic and non-diabetic settings. As a consequence of their ability to modulate tubuloglomerular feedback, SGLT2 inhibitors, like agents that block the renin-angiotensin system, reduce intraglomerular pressure and single nephron GFR, potentially affording renoprotection. To examine this further we administered the SGLT2 inhibitor, dapagliflozin, to 5/6 (subtotally) nephrectomised rats, a model of progressive chronic kidney disease (CKD) that like CKD in humans is characterised by single nephron hyperfiltration and intraglomerular hypertension and where angiotensin converting enzyme inhibitors and angiotensin receptor blockers are demonstrably beneficial. When compared with untreated rats, both sham surgery and 5/6 nephrectomised rats that had received dapagliflozin experienced substantial glycosuria. Nephrectomised rats developed hypertension, heavy proteinuria and declining GFR that was unaffected by the administration of dapagliflozin. Similarly, SGLT2 inhibition did not attenuate the extent of glomerulosclerosis, tubulointerstitial fibrosis or overexpression of the profibrotic cytokine, transforming growth factor-ß1 mRNA in the kidneys of 5/6 nephrectomised rats. While not precluding beneficial effects in the diabetic setting, these findings indicate that SGLT2 inhibition does not have renoprotective effects in this classical model of progressive non-diabetic CKD.

Comparison of the pharmacokinetics and pharmacodynamics of dapagliflozin in patients with type 1 versus type 2 diabetes mellitus.

AIMS: To compare the pharmacokinetics and pharmacodynamics of dapagliflozin in patients with type 1 diabetes mellitus (T1DM) versus type 2 diabetes mellitus (T2DM) in order to explore the potential of dapagliflozin as add-on therapy to insulin in patients with T1DM. METHODS: Steady-state pharmacokinetics and pharmacodynamics of dapagliflozin (1-100 mg) were evaluated in a meta-analysis of patients with T1DM or T2DM. A model was constructed of the relationship between dapagliflozin systemic exposure and urinary glucose excretion (UGE) in patients with T1DM versus those with T2DM. RESULTS: Data were analysed from 160 patients (T1DM, n = 70; T2DM, n = 90). Dapagliflozin systemic exposure (maximum concentration and area under the curve) increased similarly in a dose-related manner in both patient populations. Dose-dependent increases in 24-h UGE were observed with dapagliflozin in both populations. Unadjusted results showed that with regard to UGE response, dapagliflozin was more potent in patients with T1DM {mean half-maximum effective concentration [EC50 ] = 2.72 ng/ml [95% confidence interval (CI) 1.14, 5.08]} than in patients with T2DM [EC50 = 12.2 ng/ml (95% CI 4.91, 21.1)]. After normalization for baseline fasting plasma glucose, estimated glomerular filtration rate and UGE, however, the UGE potency of dapagliflozin was similar between the two populations [T1DM: mean EC50 , 8.12 ng/ml (95% CI 2.95, 14.6); T2DM: mean EC50 , 7.75 ng/ml (95% CI 1.35, 18.1)]. CONCLUSIONS: Dapagliflozin pharmacokinetics and the predicted UGE dose exposure response to dapagliflozin were similar in patients with T1DM and those with T2DM and suggest that the dapagliflozin dosages currently used for the treatment of T2DM may provide benefit as add-on therapy to insulin in patients with T1DM.

Mixed-effects modelling to quantify the effect of empagliflozin on renal glucose reabsorption in patients with type 2 diabetes.

AIMS: To quantify the effect of the sodium-glucose co-transporter 2 inhibitor, empagliflozin, on renal glucose reabsorption in patients with type 2 diabetes, and to evaluate covariate effects, using a mechanistic population pharmacokinetic-pharmacodynamic (PK-PD) model. METHODS: Four phase I/II trials were used for model development. Empagliflozin's PK characteristics were characterized by a two-compartmental model with sequential zero- and first-order absorption. Urinary glucose excretion (UGE) was described as dependent on renal glucose filtration and reabsorption; splay of the glucose reabsorption/excretion curves was considered. The modelling assumed that empagliflozin lowers the maximum renal glucose reabsorption capacity and, thereby, the renal threshold for glucose (RTg). Covariate effects were investigated using a full covariate modelling approach, emphasizing parameter estimation. RESULTS: The PK-PD model provided a reasonable description of the PK characteristics of empagliflozin and its effects on UGE across a range of renal function levels. Its parameters are consistent with reported values for renal physiology. Using this model, the effect of empagliflozin on renal glucose reabsorption was quantified. Steady-state empagliflozin doses (1, 5, 10 and 25 mg) reduced RTg from 12.5 mmol/L [95% confidence interval (CI) 12.0, 13.1] to 5.66 (95% CI 4.62, 6.72), 3.01 (95% CI 2.33, 3.69), 2.53 (95% CI 1.83, 3.14) and 2.21 (95% CI 1.47, 2.84) mg/dl, respectively. Covariate analysis showed the effect of empagliflozin on UGE was not influenced, to a clinically relevant extent, by sex, age or race. CONCLUSIONS: A method for characterizing renal glucose reabsorption was developed that does not require complex glucose clamp experiments. These analyses indicate that empagliflozin provided concentration-dependent RTg reductions, with 10 and 25 mg providing near-maximum RTg-lowering.

Pharmacokinetic and Pharmacodynamic Properties and Tolerability of Single- and multiple-dose Once-daily Empagliflozin, a Sodium Glucose Cotransporter 2 Inhibitor, in Chinese Patients With Type 2 Diabetes Mellitus.

PURPOSE: The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties and tolerability of the oral once-daily sodium glucose cotransporter 2 inhibitor empagliflozin, given in single and multiple 10 and 25 mg doses in Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: In a double-blind, placebo-controlled, parallel-group study, Chinese patients with T2DM were randomly assigned to receive a single dose of empagliflozin 10 or 25 mg or placebo on day 1 and once daily on days 3 to 9. FINDINGS: A total of 24 patients were enrolled (14 men, 10 women; median age, 53.5 years; empagliflozin 10 mg, n = 9; empagliflozin 25 mg, n = 9; and placebo, n = 6). After both single- and multiple-dose administration, empagliflozin 10 and 25 mg were rapidly absorbed, reaching peak plasma concentrations within 1 to 1.5 hours (median), with plasma levels declining biphasically. Empagliflozin exposure increased roughly dose proportionally between 10 and 25 mg. Mean terminal elimination half-life values at steady state were 13.9 and 12.1 hours with empagliflozin 10 and 25 mg, respectively. Mean (SD) changes from baseline in 24-hour urinary glucose excretion (UGE) on day 1 were +87.7 (22.9) and +82.8 (18.8) g with empagliflozin 10 and 25 mg, respectively, compared with -1.0 (2.8) g with placebo, and on day 9 were +95.8 (24.1), +82.6 (34.8) g with empagliflozin 10 and 25 mg, respectively, compared with -4.1 (6.4) g with placebo. Mean (SD) changes from baseline in fasting plasma glucose (FPG) on day 2 were -18.7 (17.2) mg/dL and -25.8 (19.6) mg/dL with empagliflozin 10 and 25 mg, respectively, compared with -4.2 (15.2) mg/dL with placebo, and on day 9, were -25.6 (20.7) mg/dL and -31.4 (26.9) mg/dL with empagliflozin 10 and 25 mg, respectively, compared to -3.7 (7.5) mg/dL with placebo. On day 10, mean changes in weight were -1.1, -1.6, and +0.5 kg with empagliflozin 10 and 25 mg and placebo, respectively. Overall, empagliflozin 10 and 25 mg had safety profiles similar to that of placebo. There were no reports of hypoglycemia, urinary tract infections, or genital infections. IMPLICATIONS: Results with single and multiple doses of empagliflozin 10 and 25 mg suggest linear pharmacokinetic properties in Chinese patients with T2DM, with a safety profile similar to that of placebo. Empagliflozin treatment was associated with increases in UGE and reductions in FPG compared with placebo. ClinicalTrials.gov identifier: NCT01316341.

Glycosuria medicated with ipragliflozin and nifedipine or ipragliflozin and candesartan: a case report.

INTRODUCTION: Animal studies have reported that treatment with angiotensin II receptor blockers reduced kidney sodium-dependent glucose cotransporter expression. We therefore hypothesized that patients with hypertension treated with an angiotensin II receptor blocker (candesartan) would probably have an increased response to sodium-dependent glucose cotransporter inhibitor therapy (ipragliflozin) compared with patients treated with alternative hypertensive medications such as calcium channel blockers (nifedipine). Although sodium-dependent glucose cotransporter inhibitor (ipragliflozin) is a new anti-diabetic medicine, the clinical efficacy in the Japanese population has not been fully evaluated. We compared the combined effect of angiotensin II receptor blocker candesartan plus ipragliflozin with nifedipine plus ipragliflozin therapy and found that the combination of candesartan plus ipragliflozin was more effective in increasing glycosuria and lowering plasma glucose. CASE PRESENTATION: A 57-year-old Japanese man with essential hypertension was treated with candesartan. Candesartan was switched to nifedipine for the initial 10 days of an observation period and 5 days later he was started on ipragliflozin (day 6 of nifedipine treatment) with nifedipine for the next 5 days. Thereafter (from day 11 to day 20), candesartan was started instead of nifedipine and ipragliflozin was continued. In the last 5 days ipragliflozin was stopped and he was treated with candesartan alone. Neither nifedipine alone (0.038+/-0.004) nor candesartan alone (0.048+/-0.006) produce any trace amount of glycosuria. However, the extent of glycosuria under ipragliflozin with candesartan treatment (37.5+/-8.45) was significantly greater than that of ipragliflozin with nifedipine (23.75+/-0.35; P<0.05). CONCLUSION: Candesartan demonstrated additive actions with ipragliflozin to increase glycosuria compared to ipragliflozin with nifedipine treatment.

Inhibition of the intestinal sodium-coupled glucose transporter 1 (SGLT1) by extracts and polyphenols from apple reduces postprandial blood glucose levels in mice and humans.

SCOPE: There is a growing interest in food constituents that could reduce intestinal glucose absorption to prevent overshooting plasma glucose and insulin levels in patients with prediabetes and diabetes mellitus type 2. METHODS AND RESULTS: We here demonstrate that an extract and individual polyphenols from apple diminish sodium-coupled glucose transporter 1 (SGLT1) mediated glucose uptake in vitro and in vivo. Inhibition of transport of sugars by SGLT1 was shown in Xenopus oocytes and in mice jejunal segments. Strongest inhibition was observed for phlorizin with IC50 values for transport inhibition of 0.46 ± 0.19 and 4.1 ± 0.6 µM in oocytes and intestinal segments, respectively. An oral glucose tolerance test performed in volunteers with prior administration of the apple extract reduced venous blood glucose and plasma insulin levels, similar to findings obtained in C57BL/6N mice. Analysis of human urine samples revealed that the extract increased modestly renal glucose loss that is most likely a result of inhibition of renal glucose reabsorption by phloretin derivatives found in plasma of the volunteers. CONCLUSION: Although the apple extract substantially decreased intestinal glucose absorption in all test systems, the finding that there are systemic effects that relate to inhibition of glucose transport processes beyond the intestine addresses safety issues that need further exploitation.

Effect of LX4211 on glucose homeostasis and body composition in preclinical models.

Treatments that lower blood glucose levels and body weight should benefit patients with type 2 diabetes mellitus (T2DM). We developed LX4211 [(2S,3R,4R,5S,6R)-2-(4-chloro-3-(4-ethoxybenzyl)phenyl)-6-(methylthio)tetrahydro-2H-pyran-3,4,5-triol], an orally available small molecule that decreases postprandial glucose excursions by inhibiting intestinal sodium/glucose cotransporter 1 (SGLT1) and increases urinary glucose excretion (UGE) by inhibiting renal SGLT2. In clinical studies of patients with T2DM, LX4211 appears to act through dual SGLT1/SGLT2 inhibition to improve glycemic control and promote weight loss. Here, we present preclinical studies that explored the ability of LX4211 to improve glycemic control and promote weight loss. We found that 1) LX4211 inhibited in vitro glucose transport mediated by mouse, rat, and dog SGLT1 and SGLT2; 2) a single daily LX4211 dose markedly increased UGE for >24 hours in mice, rats, and dogs; and 3) in the KK.Cg-Ay/J heterozygous (KKA(y)) mouse model of T2DM, LX4211 lowered A1C and postprandial glucose concentrations while increasing postprandial glucagon-like peptide 1 concentrations. Also, long-term LX4211 treatment 1) decreased oral glucose tolerance test (OGTT) glucose excursions, increased OGTT 30-minute insulin concentrations and increased pancreatic insulin content in KKA(y) mice; and 2) decreased weight gain in dogs and rats but not in KKA(y) mice while increasing food consumption in dogs, rats, and KKA(y) mice; in these KKA(y) mice, calories lost through UGE were completely offset by calories gained through hyperphagia. These findings suggest that LX4211 improves glycemic control by dual SGLT1/SGLT2 inhibition in mice as in humans, and that the LX4211-mediated weight loss observed in patients with T2DM may be attenuated by LX4211-mediated hyperphagia in some of these individuals.

Novel hypothesis to explain why SGLT2 inhibitors inhibit only 30-50% of filtered glucose load in humans.

Inhibitors of sodium-glucose cotransporter 2 (SGLT2) are a novel class of antidiabetes drugs, and members of this class are under various stages of clinical development for the management of type 2 diabetes mellitus (T2DM). It is widely accepted that SGLT2 is responsible for >80% of the reabsorption of the renal filtered glucose load. However, maximal doses of SGLT2 inhibitors fail to inhibit >50% of the filtered glucose load. Because the clinical efficacy of this group of drugs is entirely dependent on the amount of glucosuria produced, it is important to understand why SGLT2 inhibitors inhibit <50% of the filtered glucose load. In this Perspective, we provide a novel hypothesis that explains this apparent puzzle and discuss some of the clinical implications inherent in this hypothesis.

Effects of SGLT2 selective inhibitor ipragliflozin on hyperglycemia, hyperlipidemia, hepatic steatosis, oxidative stress, inflammation, and obesity in type 2 diabetic mice.

The sodium-glucose cotransporter 2 (SGLT2) is responsible for most glucose reabsorption in the kidney and has been proposed as a novel therapeutic target for the treatment of type 2 diabetes. In the present study, the therapeutic effects of SGLT2 selective inhibitor ipragliflozin were examined in high-fat diet and streptozotocin-nicotinamide-induced type 2 diabetic mice which exhibit impaired insulin secretion, insulin resistance, hyperlipidemia, hepatic steatosis, and obesity. Single administration of ipragliflozin dose-dependently increased urinary glucose excretion, reduced blood glucose and plasma insulin levels, and improved glucose intolerance. Four-week repeated administration of ipragliflozin improved not only glucose tolerance, hyperglycemia, and hyperinsulinemia but also impaired insulin secretion, hyperlipidemia, hepatic steatosis, and obesity with a concomitant increase in urinary glucose excretion. In addition, ipragliflozin reduced plasma and liver levels of oxidative stress biomarkers (thiobarbituric acid reactive substances and protein carbonyl) and inflammatory markers (interleukin 6, tumor necrosis factor α, monocyte chemotactic protein-1, and c-reactive protein), and improved liver injury as assessed by plasma levels of aminotransferases. These results demonstrate that SGLT2 selective inhibitor ipragliflozin improves not only hyperglycemia but also diabetes/obesity-associated metabolic abnormalities in type 2 diabetic mice and suggest that ipragliflozin may be useful in treating type 2 diabetes with metabolic syndrome.