Sodium-glucose cotransporter 2 inhibition and glycemic control in type 1 diabetes: results of an 8-week open-label proof-of-concept trial

Cardioprotection of Canagliflozin, Dapagliflozin, and Empagliflozin: Lessons from preclinical studies

Clinical and preclinical studies have elucidated the favorable effects of Inhibitors of Sodium-Glucose Cotransporter-2 (iSGLT2) in patients and animal models with type 2 diabetes. Notably, these inhibitors have shown significant benefits in reducing hospitalizations and mortality among patients with heart failure. However, despite their incorporation into clinical practice for indications beyond diabetes, the decision-making process regarding their use often lacks a systematic approach. The selection of iSGLT2 remains arbitrary, with only a limited number of studies simultaneously exploring the different classes of them. Currently, no unique guideline establishes their application in both clinical and basic research. This review delves into the prevalent use of iSGLT2 in animal models previously subjected to induced cardiac stress. We have compiled key findings related to cardioprotection across various animal models, encompassing diverse dosages and routes of administration. Beyond their established role in diabetes management, iSGLT2 has demonstrated utility as agents for safeguarding heart health and cardioprotection can be class-dependent among the iSGLT2. These findings may serve as valuable references for other researchers. Preclinical studies play a pivotal role in ensuring the safety of novel compounds or treatments for potential human use. By assessing side effects, toxicity, and optimal dosages, these studies offer a robust foundation for informed decisions, identifying interventions with the highest likelihood of success and minimal risk to patients. The insights gleaned from preclinical studies, which play a crucial role in highlighting areas of knowledge deficiency, can guide the exploration of novel mechanisms and strategies involving iSGLT2.

Dapagliflozin administration for 1 year promoted kidney enlargement in patient with ADPKD

To date, there is insufficient evidence regarding use of sodium-glucose cotransporter-2 (SGLT2) inhibitors for patients with autosomal-dominant polycystic kidney disease (ADPKD), as such cases have been excluded from previous clinical trials exploring the kidney protection effects of such medications. Here, findings of an ADPKD patient who received dapagliflozin, a selective SGLT2 inhibitor, for 1 year are presented. A 38-year-old woman with a family history of ADPKD wished for treatment with dapagliflozin. After starting administration at 10 mg/day, total kidney volume (TKV) continued to increase, from 1641 to 1764 mL after 84 days and then to 2297 mL after 340 days. The estimated glomerular filtration rate (eGFR) was also decreased from 67.3 to 56.2 mL/min/1.73 m2, and then to 51.4 mL/min/1.73 m2 at those times. Immediately after discontinuation of dapagliflozin, TKV and eGFR were slightly improved to 2263 mL and 55.1 mL/min/1.73 m2, respectively. Following a review of basic research studies, we consider that increased intratubular urinary osmotic pressure, compensatory glucose reabsorption by sodium-glucose cotransporter-1 in the late proximal tubule, and hypertrophy shown in collected cells caused by increased vasopressin may be associated with ADPKD disease progression. Caution may be needed when administering dapagliflozin to patients with ADPKD.

Minireview: Understanding and targeting inflammatory, hemodynamic and injury markers for cardiorenal protection in type 1 diabetes

The coexistence of cardiovascular disease (CVD) and diabetic kidney disease (DKD) is common in people with type 1 diabetes (T1D) and is strongly associated with an increased risk of morbidity and mortality. Hence, it is imperative to explore robust tools that can accurately reflect the development and progression of cardiorenal complications. Several cardiovascular and kidney biomarkers have been identified to detect at-risk individuals with T1D. The primary aim of this review is to highlight biomarkers of injury, inflammation, or renal hemodynamic changes that may influence T1D susceptibility to CVD and DKD. We will also examine the impact of approved pharmacotherapies for type 2 diabetes, including renin-angiotensin-aldosterone system (RAAS) inhibitors, sodium-glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RAs) on candidate biomarkers for cardiorenal complications in people with T1D and discuss how these changes may potentially mediate kidney and cardiovascular protection. Identifying predictive and prognostic biomarkers for DKD and CVD may highlight potential drug targets to attenuate cardiorenal disease progression, implement novel risk stratification measures in clinical trials, and improve the assessment, diagnosis, and treatment of at-risk individuals with T1D.

Interactive Effects of Empagliflozin and Hyperglycemia on Urinary Amino Acids in Individuals With Type 1 Diabetes

Optimizing energy use in the kidney is critical for normal kidney function. Here, we investigate the effect of hyperglycemia and sodium-glucose cotransporter 2 (SGLT2) inhibition on urinary amino acid excretion in individuals with type 1 diabetes (T1D). The open-label ATIRMA trial assessed the impact of 8 weeks of 25 mg empagliflozin orally once per day in 40 normotensive normoalbuminuric young adults with T1D. A consecutive 2-day assessment of clamped euglycemia and hyperglycemia was evaluated at baseline and posttreatment visits. Principal component analysis was performed on urinary amino acids grouped into representative metabolic pathways using MetaboAnalyst. At baseline, acute hyperglycemia was associated with changes in 25 of the 33 urinary amino acids or their metabolites. The most significant amino acid metabolites affected by acute hyperglycemia were 3-hydroxykynurenine, serotonin, glycyl-histidine, and nicotinic acid. The changes in amino acid metabolites were reflected by the induction of four biosynthetic pathways: aminoacyl-tRNA; valine, leucine, and isoleucine; arginine; and phenylalanine, tyrosine, and tryptophan. In acute hyperglycemia, empagliflozin significantly attenuated the increases in aminoacyl-tRNA biosynthesis and valine, leucine, and isoleucine biosynthesis. Our findings using amino acid metabolomics indicate that hyperglycemia stimulates biosynthetic pathways in T1D. SGLT2 inhibition may attenuate the increase in biosynthetic pathways to optimize kidney energy metabolism.

ARTICLE HIGHLIGHTS

Ketone production and excretion even during mild hyperglycemia and the impact of sodium-glucose co-transporter inhibition in type 1 diabetes

AIMS

We aimed to determine if ketone production and excretion are increased even at mild fasting hyperglycemia in type 1 diabetes (T1D) and if these are modified by ketoacidosis risk factors, including sodium-glucose co-transporter inhibition (SGLTi) and female sex.

METHODS

In secondary analysis of an 8-week single-arm open-label trial of empagliflozin (NCT01392560) we evaluated ketone concentrations during extended fasting and clamped euglycemia (4-6 mmol/L) and mild hyperglycemia (9-11 mmol/L) prior to and after treatment. Plasma and urine beta-hydroxybutyrate (BHB) concentrations and fractional excretion were analyzed by metabolomic analysis.

RESULTS

Forty participants (50 % female), aged 24 ± 5 years, HbA1c 8.0 ± 0.9 % (64 ± 0.08 mmol/mol) with T1D duration of 17.5 ± 7 years, were studied. Increased BHB production even during mild hyperglycemia (median urine 6.3[3.5-13.6] vs. 3.5[2.2-7.0] µmol/mmol creatinine during euglycemia, p < 0.001) was compensated by increased fractional excretion (0.9 % [0.3-1.6] vs. 0.4 % [0.2-0.9], p < 0.001). SGLTi increased production and attenuated the increased BHB fractional excretion (decreased to 0.3 % during mild hyperglycemia, p < 0.001), resulting in higher plasma concentrations (increased to 0.21 [0.05-0.40] mmol/L, p < 0.001), particularly in females (interaction p < 0.001).

CONCLUSIONS

Even mild hyperglycemia is associated with greater ketone production, compensated by urinary excretion, in T1D. However, SGLTi exaggerates production and partially reduces compensatory excretion, particularly in women.

β Cell Stress and Endocrine Function During T1D: What Is Next to Discover?

Canonically, type 1 diabetes (T1D) is a disease characterized by autoreactive T cells as perpetrators of endocrine dysfunction and β cell death in the spiral toward loss of β cell mass, hyperglycemia, and insulin dependence. β Cells have mostly been considered as bystanders in a flurry of autoimmune processes. More recently, our framework for understanding and investigating T1D has evolved. It appears increasingly likely that intracellular β cell stress is an important component of T1D etiology/pathology that perpetuates autoimmunity during the progression to T1D. Here we discuss the emerging and complex role of β cell stress in initiating, provoking, and catalyzing T1D. We outline the bridges between hyperglycemia, endoplasmic reticulum stress, oxidative stress, and autoimmunity from the viewpoint of intrinsic β cell (dys)function, and we extend this discussion to the potential role for a therapeutic β cell stress-metabolism axis in T1D. Lastly, we mention research angles that may be pursued to improve β cell endocrine function during T1D. Biology gleaned from studying T1D will certainly overlap to innovate therapeutic strategies for T2D, and also enhance the pursuit of creating optimized stem cell-derived β cells as endocrine therapy.

SGLT2 Inhibitors in the Management of Type 1 Diabetes (T1D): An Update on Current Evidence and Recommendations

SGLT2i (sodium glucose transporter type 2 inhibitors) are pharmacological agents that act by inhibiting the SGLT2, by reducing the renal plasma glucose threshold and inducing glycosuria, resulting in a blood glucose lowering effect. In recent years, studies demonstrating some additional positive effects of SGLT2i also in the treatment of T1D have increased progressively. The SGLT2i dapagliflozin and sotagliflozin have been temporarily licensed for use by the European Medical Agency (EMA) as an adjunct to insulin therapy in adults with T1D with a body mass index of 27 kg/m2 or higher. However, in the meantime, the US Food and Drug Administration (FDA) Endocrinologic and Metabolic Drugs Advisory Committee was divided, citing concerns about the main side effects of SGLT2i, especially diabetic ketoacidosis (DKA). The aim of this manuscript was to conduct an update on current evidence and recommendations of the reported use of SGLT2i in the treatment of T1D in humans. Preclinical studies, clinical trial and real world data suggest benefits in glycaemia control and nefro-cardiovascular protection, even though several studies have documented an important increase in the risk of DKA, a serious and life-threatening adverse event of these agents. SGLT2i potentially addresses some of the unmet needs associated with T1D by improving glycaemic control with weight loss and without increasing hypoglycemia, by reducing glycaemic variability. However, due to side effects, EMA recommendation for SGLT2 use on T1D was withdrawn. Further studies will be needed to determine the safety of this therapy in T1D and to define the type of patient who can benefit most from these medications.

Glucagon-like peptide-1 agonists combined with sodium-glucose cotransporter-2 inhibitors reduce weight in type 1 diabetes

OBJECTIVE

This study evaluated whether adding sodium-glucose cotransporter-2 inhibitors (SGLT2i) and/or glucagon-like peptide-1 receptor agonists (GLP1-RA) to insulin reduced weight and glycemia in people with type 1 diabetes.

METHODS

This retrospective analysis of electronic health records evaluated 296 people with type 1 diabetes over 12 months after medications were first prescribed. Four groups were defined: control n = 80, SGLT2i n = 94, GLP1-RA n = 82, and combination of drugs (Combo) n = 40. We measured changes at 1 year in weight and glycated hemoglobin (HbA1c).

RESULTS

The control group did not have changes in weight or glycemic control. The mean (SD) percentage weight loss after 12 months was 4.4% (6.0%), 8.2%  (8.5%), and 9.0% (8.4%) in the SGLT2i, GLP1-RA, and Combo groups, respectively (p < 0.001). The Combo group lost the most weight (p < 0.001). The HbA1c reduction was 0.4%  (0.7%), 0.3% (0.7%), and 0.6% (0.8%) in the SGLT2i, GLP1-RA, and Combo groups, respectively (p < 0.001). The Combo group had the biggest improvements in glycemic control and total and low-density lipoprotein cholesterol compared with baseline (all p < 0.01). Severe adverse events were similar between all the groups, with no increased risk of diabetic ketoacidosis.

CONCLUSIONS

The SGLT2i and GLP1-RA agents on their own improved body weight and glycemia, but combining the medications resulted in more weight loss. Treatment intensification appears to result in benefits with no difference in severe adverse events.

Effect of empagliflozin in patients with type 2 diabetes during Ramadan on volume status, ketonaemia, and hypoglycaemia

BACKGROUND AND AIMS

Patients with type 2 diabetes (T2D) carry higher risk of glycaemic variability during Ramadan. Glucose-lowering medications such as SGLT2 inhibitors are also associated with genitourinary infection, acute kidney injury, and euglycaemic diabetic ketoacidosis. Limited data is available on the effects of SGLT2 inhibitors on T2D patients during Ramadan. We investigated effects of empagliflozin use in fasting T2D patients.

METHODS

This was a prospective cohort study in a single diabetes centre in Malaysia. Empagliflozin group were on study drug for at least three months. For control group, subjects not receiving SGLT2 inhibitors were recruited. Follow-up were performed before and during Ramadan fasting. Anthropometric measurements, blood pressure, renal profile, and blood ketone were recorded during visits. Hypoglycaemia symptoms were assessed via hypoglycaemia symptom rating questionnaire (HypoSRQ).

RESULTS

We recruited a total of 98 subjects. Baseline anthropometry, blood pressure, and renal parameters were similar in two groups. No significant changes in blood pressure, weight, urea, creatinine, eGFR, or haemoglobin levels during Ramadan was found in either group. Likewise, no difference was detected in blood ketone levels (empagliflozin vs control, 0.17 ± 0.247 mmol/L vs 0.13 ± 0.082 mmol/L, p = 0.304) or hypoglycaemia indices (empagliflozin vs control, 19.1% vs 16%, p = 0.684).

CONCLUSIONS

Ramadan fasting resulted in weight loss and reduction in eGFR levels in patients with T2D. Empagliflozin use during Ramadan is safe and not associated with increased risk of dehydration, ketosis, or hypoglycaemia. Therefore, empagliflozin is a viable glucose-lowering drug for patients with T2D planning for Ramadan fasting.

Efficacy of Low-dose Dapagliflozin in Young People with Type 1 Diabetes

Objective Young people with type 1 diabetes are likely to gain body weight and not achieve optimal glycemic control with only high doses of insulin. This study examined the efficacy of the sodium-glucose cotransporter 2 (SGLT2) inhibitor dapagliflozin as an adjunct-to-insulin therapy in young Japanese subjects with type 1 diabetes who had been diagnosed before 15 years old, were overweight, and had inadequate control despitereceiving intensive insulin therapy. Methods Twenty-two patients with type 1 diabetes (12 boys and 10 girls 16.0-33.9 years old) were involved in the study. All patients had a body mass index (BMI) >25 kg/m², glycated hemoglobin (HbA1c) level >7.0%, and daily insulin dose >0.5 units/kg. They were treated with a low dose of dapagliflozin (5.0 mg/day) as an adjunctive therapy to insulin. Fourteen patients were treated with multiple daily injections of insulin, while eight used an insulin pump. Results The body weights and BMIs were significantly reduced during the 12-month study period (change of -4.4 kg and -1.7 kg/m², p<0.001, respectively). Their insulin dose was significantly decreased (-0.17 units/kg, P <0.001), and glycemic control was significantly improved (fasting plasma glucose: -18.7 mg/dL, HbA1c: -0.62%, p<0.001) during the study period. There was one episode of diabetic ketoacidosis, with no other problematic adverse events, including severe hypoglycemia, observed. Conclusion The use of low-dose dapagliflozin as an adjunct therapy may be beneficial in overweight young people with poorly controlled type 1 diabetes.

Knowledge domain and emerging trends in empagliflozin for heart failure: A bibliometric and visualized analysis

Objective

Empagliflozin (EMPA), a sodium-glucose cotransporter 2 inhibitor (SGLT2i), is recommended for all patients with Heart failure (HF) to reduce the risk of Cardiovascular death, hospitalization, and HF exacerbation. Qualitative and quantitative evaluation was conducted by searching relevant literatures of EMPA for Heart Failure from 2013 to 2022, and visual analysis in this field was conducted.

Methods

The data were from the Web of Science Core Collection database (WOSCC). The bibliometric tools, CiteSpace and VOSviewer, were used for econometric analysis to probe the evolvement of disciplines and research hotspots in the field of EMPA for Heart Failure.

Results

A total of 1461 literatures with 43861 references about EMPA for Heart Failure in the decade were extracted from WOSCC, and the number of manuscripts were on a rise. In the terms of co-authorship, USA leads the field in research maturity and exerts a crucial role in the field of EMPA for Heart Failure. Multidisciplinary research is conducive to future development. With regards to literatures, we obtained 9 hot paper, 93 highly cited literatures, and 10 co-cited references. The current research focuses on the following three aspects: EMPA improves left ventricular remodeling, exert renal protection, and increases heart rate variability.

Conclusion

Based on methods such as bibliometrics, citation analysis and knowledge graph, this study analyzed the current situation and trend of EMPA for Heart Failure, sorted out the knowledge context in this field, and provided reference for current and future prevention and scientific research.

Sodium-Glucose Co-Transporter-2 Inhibitors in Type 1 Diabetes: A Scoping Review

BACKGROUND

With recent developments in diabetes technology, attaining adequate glucose control is more achievable than ever. Despite these improvements, a significant proportion of individuals with type 1 diabetes do not reach recommended glycaemic goals. Sodium-glucose co-transporter-2 (SGLT2) inhibitors are glucose-lowering agents that inhibit the reabsorption of filtered glucose in the kidneys, thus promoting glucosuria. Because the glucose-lowering effect of SGLT2 inhibitors is achieved independently of insulin secretion, it has been speculated whether they could bridge the gap towards achieving glycaemic targets in individuals with type 1 diabetes.

SUMMARY

Our main goal was to systematically map the current knowledge on the efficacy and safety of SGLT2 inhibitor use in adults with type 1 diabetes and present recent studies regarding the use of SGLT2 inhibitors in youth with type 1 diabetes. Using a scoping review approach, we searched MEDLINE to identify relevant clinical trials of SGLT2 inhibitors as adjunctive therapy to insulin in type 1 diabetes published from January 31, 2012, to January 31, 2022. We included the most relevant, large-scale, and long placebo-controlled clinical trials of SGLT2 inhibitors as an add-on therapy to insulin in adults with type 1 diabetes. Additionally, we included all relevant pilot studies evaluating the use of SGLT2 inhibitors as add-on therapy to insulin in youth with type 1 diabetes. We identified eight placebo-controlled clinical trials in adults with type 1 diabetes meeting our inclusion criteria and two relevant pilot studies in youth with type 1 diabetes. The clinical trials in adults with type 1 diabetes confirmed the efficacy of SGLT2 inhibitors as add-on therapy to insulin. However, this was associated with an increased incidence of diabetic ketoacidosis (DKA) versus placebo in all identified clinical trials. The two relevant pilot studies in youth with type 1 diabetes showed promising results of SGLT2 inhibitor use as an add-on therapy to insulin, especially when combined with a fully closed-loop system.

KEY MESSAGES

SGLT2 inhibitors, as an add-on therapy to insulin, improve glycaemic outcomes in adults with type 1 diabetes with a potential cost of increasing DKA risk. The use of add-on SGLT2 inhibitors to insulin shows promising results in youth with type 1 diabetes. Moreover, SGLT2 inhibitors as add-on therapy in combination with closed-loop insulin therapy could provide additional benefits in improving glycaemic control. The current role of SGLT2 inhibitors as an adjunct therapy to insulin in individuals with type 1 diabetes is yet to be determined.

Empagliflozin induces apoptotic-signaling pathway in embryonic vasculature: In vivo and in silico approaches via chick’s yolk sac membrane model

The present investigation was conducted to evaluate the vascular-toxicity of empagliflozin (EMP) in embryonic vasculature. Firstly, the vascular-toxicity of the drug as well as its interaction with apoptotic regulator proteins was predicted via in silico approach. In the next step, the apoptotic-signaling pathway in embryonic vasculature was evaluated using a chick’s YSM model. In silico simulation confirmed vascular-toxicity of EMP. There was also an accurate affinity between EMP, Bax and Bcl-2 (−7.9 kcal/mol). Molecular dynamics assay revealed complex stability in the human body conditions. Furthermore, EMP is suggested to alter Bcl-2 more than BAX. Morphometric quantification of the vessels showed that the apoptotic activity of EMP in embryonic vasculature was related to a marked reduction in vessel area, vessel diameter and mean capillary area. Based on the qPCR and immunohistochemistry assays, enhanced expression level of BAX and reduced expression level of Bcl-2 confirmed apoptotic responses in the vessels of the YSM. We observed that induction of an apoptotic signal can cause the embryonic defect of the vascular system following EMP treatment. The acquired data also raised suspicions that alteration in apoptotic genes and proteins in the vasculature are two critical pathways in vascular-toxicity of EMP.

Effects of Dapagliflozin and Combination Therapy With Exenatide on Food-Cue Induced Brain Activation in Patients With Type 2 Diabetes

CONTEXT

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) cause less weight loss than expected based on urinary calorie excretion. This may be explained by SGLT2i-induced alterations in central reward and satiety circuits, leading to increased appetite and food intake. Glucagon-like peptide-1 receptor agonists are associated with reduced appetite and body weight, mediated by direct and indirect central nervous system (CNS) effects.

OBJECTIVE

We investigated the separate and combined effects of dapagliflozin and exenatide on the CNS in participants with obesity and type 2 diabetes.

METHODS

This was a 16-week, double-blind, randomized, placebo-controlled trial. Obese participants with type 2 diabetes (n = 64, age 63.5 ± 0.9 years, BMI 31.7 ± 0.6 kg/m2) were randomized (1:1:1:1) to dapagliflozin 10 mg with exenatide-matched placebo, exenatide twice daily 10 µg with dapagliflozin-matched placebo, dapagliflozin and exenatide, or double placebo. Using functional MRI, the effects of treatments on CNS responses to viewing food pictures were assessed after 10 days and 16 weeks of treatment.

RESULTS

After 10 days, dapagliflozin increased, whereas exenatide decreased CNS activation in the left putamen. Combination therapy had no effect on responses to food pictures. After 16 weeks, no changes in CNS activation were observed with dapagliflozin, but CNS activation was reduced with dapagliflozin-exenatide in right amygdala.

CONCLUSION

The early increase in CNS activation with dapagliflozin may contribute to the discrepancy between observed and expected weight loss. In combination therapy, exenatide blunted the increased CNS activation observed with dapagliflozin. These findings provide further insights into the weight-lowering mechanisms of SGLT2i and GLP-1 receptor agonists.

Efficacy and Safety of SGLT2 Inhibitors as Adjunctive Treatment in Type 1 Diabetes in a Tertiary Care Center in Saudi Arabia

Background  Adjunctive treatment with sodium-glucose co-transporters 2 inhibitors (SGLT2- I) has been successfully used in patients with type 1 diabetes mellitus (T1DM) in recent years to improve glycemic control and reduce body weight without increasing the risk of hypoglycemia; however, there is a scarcity of evidence for real-world experience in their use in T1DM Saudi patients. The purpose of this study was to evaluate the efficacy and safety of empagliflozin as off-label adjunctive therapy in Saudi patients with T1DM. Methods  This study was a retrospective study for T1DM patients, who were prescribed empagliflozin as an adjunctive therapy. Baseline characteristics including age, changes in HbA1c, body weight, total daily insulin dose, lipid profile, and well as side effects such as urinary tract infections (UTIs) and diabetes ketoacidosis (DKA) were evaluated before and after initiation empagliflozin in 37 T1DM patients. Results  The mean age was 25.8 ± 8.0 years, mean weight was 75.3 ± 14.8 kg, mean body mass index (BMI) was 28.1 ± 6.7 kg/m 2 , mean duration of diabetes was 10.1 ± 6.5 years, and mean HbA1c was 9.4 ± 1.4%. After a mean follow-up duration of 15.8 ± 6.0 months, the mean reduction in the HbA1c% from baseline was 0.82% ( p  = 0.001) and mean weight reduction from baseline was 1.7 kg ( p  = 0.097). The total daily insulin dose was decreased by 2.9 units. UTIs and DKA episodes were reported among 2.7% and 10.8% of the participants, respectively. Conclusion  Empagliflozin in combination with insulin in overweight Saudi T1DM subjects resulted in a significant improvement in glycemic control, mild non-significant reduction in body weight, and a small but statistically significant reduction in the total daily insulin dose with a slight increase in the risk of DKA and UTIs. Further larger prospective studies are needed for better evaluation of the efficacy and safety of these agents in Saudi T1DM patients.

Brain Activation in Response to Low-Calorie Food Pictures: An Explorative Analysis of a Randomized Trial With Dapagliflozin and Exenatide

BACKGROUND AND AIM

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) induce less weight loss than expected. This may be explained by SGLT2i-induced alterations in central reward and satiety circuits, contributing to increased appetite and food intake. This hyperphagia may be specific to high-calorie foods. Glucagon-like peptide-1 receptor agonists (GLP-1RA) are associated with lower preferences for high-calorie foods, and with decreased activation in areas regulating satiety and reward in response to high-calorie food pictures, which may reflect this lower preference for energy-dense foods. To optimize treatment, we need a better understanding of how intake is controlled, and how [(un)healthy] food choices are made. The aim of the study was to investigate the effects of dapagliflozin, exenatide, and their combination on brain activation in response to low-calorie food pictures.

METHODS

We performed an exploratory analysis of a larger, 16-week, double-blind, randomized, placebo-controlled trial. Sixty-eight subjects with obesity and type 2 diabetes were randomized to dapagliflozin, exenatide, dapagliflozin plus exenatide, or double placebo. Using functional MRI, the effects of treatments on brain responses to low-calorie food pictures were assessed after 10 days and 16 weeks.

RESULTS

Dapagliflozin versus placebo decreased activity in response to low-calorie food pictures, in the caudate nucleus, insula, and amygdala after 10 days, and in the insula after 16 weeks. Exenatide versus placebo increased activation in the putamen in response to low-calorie food pictures after 10 days, but not after 16 weeks. Dapagliflozin plus exenatide versus placebo had no effect on brain responses, but after 10 days dapagliflozin plus exenatide versus dapagliflozin increased activity in the insula and amygdala in response to low-calorie food pictures.

CONCLUSION

Dapagliflozin decreased activation in response to low-calorie food pictures, which may reflect a specific decreased preference for low-calorie foods, in combination with the previously found increased activation in response to high-calorie foods, which may reflect a specific preference for high-calorie foods, and may hamper SGLT2i-induced weight loss. Exenatide treatment increased activation in response to low-calorie foods. Combination treatment may lead to more favorable brain responses to low-calorie food cues, as we observed that the dapagliflozin-induced decreased response to low-calorie food pictures had disappeared.

Renal Tubular Handling of Glucose and Fructose in Health and Disease

The proximal tubule of the kidney is programmed to reabsorb all filtered glucose and fructose. Glucose is taken up by apical sodium-glucose cotransporters SGLT2 and SGLT1 whereas SGLT5 and potentially SGLT4 and GLUT5 have been implicated in apical fructose uptake. The glucose taken up by the proximal tubule is typically not metabolized but leaves via the basolateral facilitative glucose transporter GLUT2 and is returned to the systemic circulation or used as an energy source by distal tubular segments after basolateral uptake via GLUT1. The proximal tubule generates new glucose in metabolic acidosis and the postabsorptive phase, and fructose serves as an important substrate. In fact, under physiological conditions and intake, fructose taken up by proximal tubules is primarily utilized for gluconeogenesis. In the diabetic kidney, glucose is retained and gluconeogenesis enhanced, the latter in part driven by fructose. This is maladaptive as it sustains hyperglycemia. Moreover, renal glucose retention is coupled to sodium retention through SGLT2 and SGLT1, which induces secondary deleterious effects. SGLT2 inhibitors are new anti-hyperglycemic drugs that can protect the kidneys and heart from failing independent of kidney function and diabetes. Dietary excess of fructose also induces tubular injury. This can be magnified by kidney formation of fructose under pathological conditions. Fructose metabolism is linked to urate formation, which partially accounts for fructose-induced tubular injury, inflammation, and hemodynamic alterations. Fructose metabolism favors glycolysis over mitochondrial respiration as urate suppresses aconitase in the tricarboxylic acid cycle, and has been linked to potentially detrimental aerobic glycolysis (Warburg effect). © 2022 American Physiological Society. Compr Physiol 12:2995-3044, 2022.

Effect of short-term use of dapagliflozin on impaired awareness of hypoglycaemia in people with type 1 diabetes

AIM

Impaired awareness of hypoglycaemia (IAH) affects about 25% of patients with type 1 diabetes (T1DM). IAH can be reversed by strict avoidance of hypoglycaemia for at least 3 weeks. Adjunctive treatment with sodium glucose cotransporter 2 inhibitors may reduce the risk of hypoglycaemia through reduction of glucose variability. We tested the hypothesis that short-term use of dapagliflozin may improve awareness of hypoglycaemia in people with T1DM and IAH.

MATERIALS AND METHODS

Fifteen patients with T1DM and IAH were included in this randomized double-blind, placebo-controlled cross-over trial (age 49.7 ± 14.6 years, 40% men, disease duration 24.1 ± 14.2 years, glycated haemoglobin 7.5 ± 0.8% (58.6 ± 8.4 mmol/mol). They were treated with dapagliflozin 10 mg once daily or matching placebo, with a washout period of 2 weeks. At the end of each treatment period, participants underwent a modified hyperinsulinaemic normoglycaemic-hypoglycaemic glucose clamp (glucose nadir 2.5 mmol/L). Blinded continuous glucose monitors were used in the final treatment weeks.

RESULTS

Treatment with dapagliflozin significantly improved glycated haemoglobin [-0.32 ± 0.10 vs. 0.22 ± 0.13% (-4.1 ± 0.9 vs. 2.3 ± 1.4 mmol/mol), dapagliflozin vs. placebo, p = .007] and glucose variability (standard deviation, 2.6 ± 0.2 vs. 3.1 ± 0.3 mmol/L, p = .029), but did not affect the frequency of hypoglycaemia. During the hypoglycaemic clamp, dapagliflozin did not affect symptom responses (8.0 ± 3.4 vs. 5.2 ± 1.6, p = .31), but significantly reduced the need for exogenous glucose to maintain hypoglycaemia (3.2 ± 0.3 vs. 4.1 ± 0.4 mg/kg/min, p = .022).

CONCLUSIONS

Eight weeks of treatment with dapagliflozin did not restore hypoglycaemic awareness in people with T1DM and impaired awareness of hypoglycaemia, but ameliorated some clinical aspects.

Changes in plasma and urine metabolites associated with empagliflozin in patients with type 1 diabetes

AIM

To examine the impact of the sodium-glucose co-transporter-2 inhibitor, empagliflozin, on plasma and urine metabolites in participants with type 1 diabetes.

MATERIAL AND METHODS

Participants (n = 40, 50% male, mean age 24.3 years) with type 1 diabetes and without overt evidence of diabetic kidney disease had baseline assessments performed under clamped euglycaemia and hyperglycaemia, on two consecutive days. Participants then proceeded to an 8-week, open-label treatment period with empagliflozin 25 mg/day, followed by repeat assessments under clamped euglycaemia and hyperglycaemia. Plasma and urine metabolites were first grouped into metabolic pathways using MetaboAnalyst software. Principal component analysis was performed to create a representative value for each sufficiently represented metabolic group (false discovery rate ≤ 0.1) for further analysis.

RESULTS

Of the plasma metabolite groups, tricarboxylic acid (TCA) cycle (P < .0001), biosynthesis of unsaturated fatty acids (P = .0045), butanoate (P < .0001), propanoate (P = .0053), and alanine, aspartate and glutamate (P < .0050) metabolites were increased after empagliflozin treatment under clamped euglycaemia. Of the urine metabolite groups, only butanoate metabolites (P = .0005) were significantly increased. Empagliflozin treatment also attenuated the increase in a number of urine metabolites observed with acute hyperglycaemia.

CONCLUSIONS

Empagliflozin was associated with increased lipid and TCA cycle metabolites in participants with type 1 diabetes, suggesting a shift in metabolic substrate use and improved mitochondrial function. These effects result in more efficient energy production and may contribute to end-organ protection by alleviating local hypoxia and oxidative stress.

Sodium/glucose cotransporter 2 inhibitors for the treatment of type 1 diabetes: what are the latest developments?

Despite the improvements in insulin therapy, many patients with type 1 diabetes mellitus (T1DM) do not achieve glycemic targets. Hypoglycemia and weight gain are important barriers in reaching these targets. Sodium/glucose cotransporter 2 (SGLT2) inhibitors lack these side effects and have an insulin-independent mechanism of action. Therefore, they might be useful in patients with T1DM. The authors discuss the safety and efficacy of SGLT2 inhibitors in T1DM. Several randomized controlled trials have evaluated dapagliflozin, sotagliflozin and empagliflozin in this population whereas fewer data are available for other members of this class. In these studies, SGLT2 inhibitors reduced HbA1c levels and body weight without a greater risk of hypoglycemia. However, a higher incidence of diabetic ketoacidosis (DKA) was observed in patients treated with these agents. SGLT2 inhibitors improve glycemic control in patients with T1DM but this effect is modest. Even though weight loss and the neutral effect on the incidence of hypoglycemia are advantages of these agents, the increased risk of DKA is a cause of concern. Overall, SGLT2 inhibitors should be used with caution and only in carefully selected patients with T1DM who are motivated, adherent to treatment, well-trained in recognizing DKA and are closely followed-up.

Comparative efficacy of empagliflozin versus placebo in the treatment of type 1 diabetes mellitus: a meta-analysis of randomized controlled trials

The objective of this meta-analysis study was to evaluate the comparative efficacy of empagliflozin (25 mg) with placebo in the treatment and management of type 1 diabetes mellitus. This study is a meta-analysis, so an ethical statement is not required. Different databases and individual journal websites like SCOPUS, Science direct, Cochrane review library etc. were used. The articles were evaluated based on the search and eligibility criteria. A total of five RCTs were incorporated in this meta-analysis. These studies contained a total of 1058 patients, including 526 patients with placebo (or control-treated patients), and 532 patients with empagliflozin (25 mg) treated combination. The mean follow-up time ranged from 7 days to 6 months. Overall, mean reduction in placebo was -0.50% and empa-treated was -0.85%, while the pooled WMD was 3.82 995% CI 1.20 – 5.88, p=0.0001). Regarding urinary glucose excretion, that the pooled WMD was 6.67 (95% CI 4.87-10.14, p=0.001) indicated a significant increase in empa-arm compared to placebo. No heterogeneity was found (I2 – 15.03%). This meta-analysis underlined the therapeutic benefit of empagliflozin as an adjunctive therapy for patients with type 1 diabetes.

Sodium-glucose cotransporter 2 inhibitors as an add-on therapy to insulin for type 1 diabetes mellitus: Meta-analysis of randomized controlled trials

AIMS

The aim was to systematically review the efficacy and safety of sodium-glucose cotransporter inhibitor (SGLT2i) as an adjunct to insulin at different follow-up durations in randomized, double-blind clinical trials in patients with type 1 diabetes.

METHODS

We conducted a search on Medline, Embase, and the Cochrane Library for relevant studies published before May 2020. According to the duration of follow-up, the subgroup analysis included four periods: 1-4, 12-18, 24-26, and 52 weeks. In the five trials included both 24-26 and 52 weeks of follow-up, we compared the efficacy by the placebo-subtracted difference and changes in SGLT2i groups.

RESULTS

Fifteen trials including 7109 participants were analyzed. The combination of SGLT2i and insulin improved hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), daily insulin dose, body weight, and blood pressure, which varied greatly by different follow-ups. Compared with %HbA1c at 24-26 weeks, placebo-subtracted differences and changes in the SGLT2i groups slightly increased. SGLT2i plus insulin treatment showed no difference in the occurrence of urinary tract infections (UTIs), hypoglycemia, or severe hypoglycemia but increased the risk of genital tract infections (GTIs) in a duration-dependent manner. SGLT2i treatment was associated with a significantly higher rate of ketone-related SAEs and diabetic ketoacidosis (DKA) at 52 weeks.

CONCLUSION

SGLT2i as an add-on therapy to insulin improved glycemic control and body weight and decreased the required dose of insulin without increasing the risk of hypoglycemia. However, after 6 months the benefits of SGLT2is on glycemic control may weaken and the risks of GTIs and DKA increased.

Renal gluconeogenesis in insulin resistance: A culprit for hyperglycemia in diabetes

Renal gluconeogenesis is one of the major pathways for endogenous glucose production. Impairment in this process may contribute to hyperglycemia in cases with insulin resistance and diabetes. We reviewed pertinent studies to elucidate the role of renal gluconeogenesis regulation in insulin resistance and diabetes. A consensus on the suppressive effect of insulin on kidney gluconeogenesis has started to build up. Insulin-resistant models exhibit reduced insulin receptor (IR) expression and/or post-receptor signaling in their kidney tissue. Reduced IR expression or post-receptor signaling can cause impairment in insulin’s action on kidneys, which may increase renal gluconeogenesis in the state of insulin resistance. It is now established that the kidney contributes up to 20% of all glucose production via gluconeogenesis in the post-absorptive phase. However, the rate of renal glucose release excessively increases in diabetes. The rise in renal glucose release in diabetes may contribute to fasting hyperglycemia and increased postprandial glucose levels. Enhanced glucose release by the kidneys and renal expression of the gluconeogenic-enzyme in diabetic rodents and humans further point towards the significance of renal gluconeogenesis. Overall, the available literature suggests that impairment in renal gluconeogenesis in an insulin-resistant state may contribute to hyperglycemia in type 2 diabetes.

Dapagliflozin elevates plasma high-density lipoprotein levels and influences visceral fat gene expression in streptozotocin-induced diabetes mellitus

OBJECTIVES

Dapagliflozin (Dapa) could potentially be used to treat type 1 diabetes mellitus. We tested the hypothesis that it would influence blood lipid levels and visceral fat accumulation in a rodent diabetic model.

METHODS

We used three groups of male Wistar rats: Controls, streptozotocin (STZ)-treated rats and STZ-treated orally with Dapa (STZ+Dapa), 10 mg/kg/day for six weeks. Blood glucose and serum lipids levels were determined. Plasma levels of lipases (hormone-sensitive lipase, HSL and lipoprotein lipase, LPL), adipokines (leptin and adiponectin) and proinflammatory cytokines [tumour necrosis factor-alpha (TNFα) and interleukin-6 (IL-6)] were determined by ELISA assays. mRNA levels in the perirenal fat were determined by real-time PCR.

KEY FINDINGS

Dapa suppressed STZ-related hyperglycemia by 20% (P < 0.05) and increased serum HDL when compared to the controls and the STZ-only treated rats (both P < 0.05). STZ treatment caused elevations of other serum lipids that were resistant to Dapa treatment. Dapa treatment also increased both plasma and visceral fat mRNA levels of leptin, LPL and IL-6, while decreasing plasma and fat expressions of HSL and TNFα compared to the STZ-only treated rats (all P < 0.05).

CONCLUSIONS

Our results suggest that Dapa, in addition to its antidiabetic effect, also influences the function of adipose tissue which could be beneficial in the treatment of diabetes.

Sodium-glucose cotransporter-2-induced euglycemic diabetic ketoacidosis unmasks latent autoimmune diabetes in a patient misdiagnosed with type 2 diabetes mellitus: a case report

BACKGROUND

Euglycemic diabetic ketoacidosis is an uncommon but life-threatening complication associated with the use of sodium-glucose cotransporter 2 inhibitors that causes lower than expected blood glucose levels typically seen in diabetic ketoacidosis.

CASE PRESENTATION

We present a case of 64-year-old Caucasian male patient previously diagnosed with type 2 diabetes treated with a sodium-glucose cotransporter 2 inhibitor who developed severe ketoacidosis. Serum glucose levels on initial presentation were slightly above normal baseline level. The patient was revealed to have latent autoimmune diabetes in adults.

CONCLUSION

This case highlights the importance of prescribing sodium-glucose cotransporter 2 inhibitors to the correct patient population and the significance of accurately differentiating between various types of diabetes.

Association of British Clinical Diabetologists (ABCD) and Diabetes UK joint position statement and recommendations on the use of sodium-glucose cotransporter inhibitors with insulin for treatment of type 1 diabetes (Updated October 2020)

Dapagliflozin (SGLT-2 inhibitor) and sotagliflozin (SGLT1/2 inhibitor) are two of the drugs of SGLT inhibitor class which have been recommended by the National Institute for Health and Care Excellence (NICE) in people with type 1 diabetes with BMI ≥27 kg/m² . Dapagliflozin is licensed in the UK for use in the NHS while sotagliflozin may be available in future. These and possibly other SGLT inhibitors may be increasingly used in people with type 1 diabetes as new licences are obtained. These drugs have the potential to improve glycaemic control in people with type 1 diabetes with the added benefit of weight loss, better control of blood pressure and more time in optimal glucose range. However, SGLT inhibitors are associated with a higher incidence of diabetic ketoacidosis without significant hyperglycaemia. The present ABCD/Diabetes UK joint updated position statement is to guide people with type 1 diabetes and clinicians using these drugs help mitigate this risk and other potential complications. Particularly, caution needs to be exercised in people who are at risk of diabetic ketoacidosis due to low calorie diets, illnesses, injuries, starvation, excessive exercise, excessive alcohol consumption and reduced insulin administration among other precipitating factors for diabetic ketoacidosis.

A systematic review and dose-response meta-analysis on the efficacy of dapagliflozin in patients with type 1 diabetes mellitus

Formulation of insulin analogs and its delivery are developed in over recent years but glycemic control in most patients with type-1 diabetes mellitus (DM) is not adequate yet. The aim of this meta-analysis is to evaluate the efficacy of dapagliflozin in patients with type-1 DM. The MEDLINE/PubMed, Scopus, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases were searched up to Aug 2020 to identify the potential literature. Random-effects model (DerSimonian and Laird method) was used to estimate the pooled effect size as weighted mean difference (WMD) with 95 % confidence interval (CI). Five randomized placebo-controlled trials with 11 arms were included in the quantitative analysis. The pooled results suggested a significant reduction in glycated hemoglobin A1C (HbA1C; WMD: -0.36 %, 95 % CI: -0.55, -0.18), body weight (WMD: -4.02 kg, 95 % CI: -4.78, -3.25), and total daily insulin dose (TDID; WMD: -10.36 %, 95 % CI: -13.42, -7.29), as well as an increase in 24-h urinary glucose excretion (24-h UGE; WMD: 90.02 g/24-h, 95 % CI: 72.96, 107.09) in dapagliflozin group compared to control group. Dose of dapagliflozin had a significant effect on body weight reduction (Coef = -3.7, p = 0.01) and 24-h UGE (coef = 0.85, p = 0.005). Pooled results of this meta-analysis identified a significant reduction in HbA1c levels, body weight, and TDID, and a substantial increase in 24-h UGE in patients who received dapagliflozin versus placebo.

Adjunct therapies in treatment of type 1 diabetes

In spite of developments with novel insulin preparations, novel modes of insulin delivery with insulin infusion pumps, and the facility of continuous glucose monitoring, only 20% of patients with type 1 diabetes are under adequate control. The need for innovation is clear, and, therefore, the use of adjunct therapies with other pharmacological agents currently in use for type 2 diabetes, has been tried. Currently, pramlintide is the only agent licensed for use in this condition in addition to insulin. Global trials have been conducted with liraglutide, a glucagon-like peptide 1 receptor agonist (GLP-1RA), dapagliflozin, a sodium glucose cotransporter 2 (SGLT2) inhibitor, and sotagliflozin, an inhibitor of both SGLT1 and SGLT2 transporters. While dapagliflozin and sotagliflozin have now been licensed for clinical use in this condition in Europe and Japan, they have hitherto not been licensed in the United States due to a small increase in the risk of diabetic ketoacidosis. However, these agents reduce glycosylated hemoglobin (HbA1c) by 0.4%, reduce glycemic oscillations, and do not increase the risk of hypoglycemia. Liraglutide, on the other hand, induced a smaller reduction in HbA1c and thus was not considered for a license. However, further trials are currently being conducted with a combination of semaglutide, the most potent GLP-1RA, and dapagliflozin to determine whether this approach would yield better outcomes.

Renal physiology of glucose handling and therapeutic implications

The rationale for using sodium-glucose cotransporter 2 (SGLT2) inhibitors in patients with type 2 diabetes (T2D) has evolved over the last decade. Due to the effects on glucosuria and body weight loss, SGLT2 inhibitors were originally approved for glycemic control in T2D. Since glucosuria is attenuated in chronic kidney disease (CKD) Stages 3–5, initial regulatory approval for SGLT2 inhibitor use was limited to patients with T2D and preserved estimated glomerular filtration rate. Over time, however, it has become increasingly apparent that these therapies have a variety of important pharmacodynamic and clinical effects beyond glycemic lowering, including antihypertensive and antialbuminuric properties, and the ability to reduce glomerular hypertension. Importantly, these sodium-related effects are preserved across CKD stages, despite attenuated glycemic effects, which are lost at CKD Stage 4. With the completion of cardiovascular (CV) outcome safety trials—EMPA-REG OUTCOME, CANVAS Program and DECLARE TIMI-58—in addition to reductions in CV events, SGLT2 inhibition consistently reduces hard renal endpoints. Importantly, these CV and renal effects are independent of glycemic control. Subsequent data from the recent CREDENCE trial—the first dedicated renal protection trial with SGLT-2 inhibition—demonstrated renal and CV benefits in albuminuric T2D patients, pivotal results that have expanded the clinical importance of these therapies. Ongoing trials will ultimately determine whether SGLT2 inhibition will have a role in renal protection in other clinical settings, including nondiabetic CKD and type 1 diabetes.

Glucose transporters in the kidney in health and disease

The kidneys filter large amounts of glucose. To prevent the loss of this valuable fuel, the tubular system of the kidney, particularly the proximal tubule, has been programmed to reabsorb all filtered glucose. The machinery involves the sodium-glucose cotransporters SGLT2 and SGLT1 on the apical membrane and the facilitative glucose transporter GLUT2 on the basolateral membrane. The proximal tubule also generates new glucose, particularly in the post-absorptive phase but also to enhance bicarbonate formation and maintain acid-base balance. The glucose reabsorbed or formed by the proximal tubule is primarily taken up into peritubular capillaries and returned to the systemic circulation or provided as an energy source to further distal tubular segments that take up glucose by basolateral GLUT1. Recent studies provided insights on the coordination of renal glucose reabsorption, formation, and usage. Moreover, a better understanding of renal glucose transport in disease states is emerging. This includes the kidney in diabetes mellitus, when renal glucose retention becomes maladaptive and contributes to hyperglycemia. Furthermore, enhanced glucose reabsorption is coupled to sodium retention through the sodium-glucose cotransporter SGLT2, which induces secondary deleterious effects. As a consequence, SGLT2 inhibitors are new anti-hyperglycemic drugs that can protect the kidneys and heart from failing. Recent studies discovered unique roles for SGLT1 with implications in acute kidney injury and glucose sensing at the macula densa. This review discusses established and emerging concepts of renal glucose transport, and outlines the need for a better understanding of renal glucose handling in health and disease.

Sodium glucose co-transporter 2 inhibition reduces succinate levels in diabetic mice

BACKGROUND

Type 1 diabetes (T1D) is associated with major chronic microvascular complications which contribute significantly to diabetes associated morbidity. The protein primarily responsible for glucose reabsorption in the kidney is sodium glucose co-transporter 2 (SGLT2). Presently, SGLT2 inhibitors are widely used in diabetic patients to improve blood glucose levels and prevent cardiovascular and renal complications. Given the broad therapeutic application of SGLT2 inhibitors, we hypothesised that SGLT2 inhibition may exert its protective effects via alterations of the gut microbiome and tested this in a type 1 diabetic mouse model of diabetic retinopathy.

AIM

To determine whether the treatment with two independent SGLT2 inhibitors affects gut health in a type 1 diabetic mouse model.

METHODS

The SGLT2 inhibitors empagliflozin or dapagliflozin (25 mg/kg/d) or vehicle dimethylsulfoxide (DMSO) were administered to C57BL/6J, Akita, Kimba and Akimba mice at 10 wk of age for 8 wk via their drinking water. Serum samples were collected and the concentration of succinate and the short chain fatty acid (SCFA) butyric acid was measured using gas chromatography-mass spectrometry. Enzyme-linked immunosorbent assay (ELISA) was performed to determine the concentration of insulin and leptin. Furthermore, the norepinephrine content in kidney tissue was determined using ELISA. Pancreatic tissue was collected and stained with haematoxylin and eosin and analysed using brightfield microscopy.

RESULTS

Due to the presence of the Akita allele, both Akita and Akimba mice showed a reduction in insulin production compared to C57BL/6J and Kimba mice. Furthermore, Akita mice also showed the presence of apoptotic bodies within the pancreatic islets. The acinar cells of Akita and Akimba mice showed swelling which is indicative of acute injury or pancreatitis. After 8 wk of SGLT2 inhibition with dapagliflozin, the intermediate metabolite of gut metabolism known as succinate was significantly reduced in Akimba mice when compared to DMSO treated mice. In addition, empagliflozin resulted in suppression of succinate levels in Akimba mice. The beneficial SCFA known as butyric acid was significantly increased in Akita mice after treatment with dapagliflozin when compared to vehicle treated mice. The norepinephrine content in the kidney was significantly reduced with both dapagliflozin and empagliflozin therapy in Akita mice and was significantly reduced in Akimba mice treated with empagliflozin. In non-diabetic C57BL/6J and Kimba mice, serum leptin levels were significantly reduced after dapagliflozin therapy.

CONCLUSION

The inhibition of SGLT2 reduces the intermediate metabolite succinate, increases SCFA butyric acid levels and reduces norepinephrine content in mouse models of T1D. Collectively, these improvements may represent an important mechanism underlying the potential benefits of SGLT2 inhibition in T1D and its complications.

The comparison of efficacy and safety between different doses of empagliflozin in insulin-treated type 1 diabetes mellitus patients: a systematic review and meta-analysis protocol

OBJECTIVES

The proposed review aims to compare the efficacy and safety profile of empagliflozin 25 mg with its lower dosages and placebo, respectively, in insulin-treated type 1 diabetes mellitus (T1DM) patients.

METHODS

Double-blinded randomized controlled trials comparing the above outcomes will be searched primarily in three electronic databases (PubMed, Embase, and Scopus) and eligible trials will be included in the proposed review. Then, from the trials recruited in the review, data of the study design, participants, interventions compared, and outcomes of interest will be extracted. Subsequently, the trials' risk of bias will be assessed using the Cochrane Collaboration's tool. The meta-analysis will be conducted with a fixed-effect or a random-effect model to estimate the mean differences (weighted or standardized) and risk ratios for the efficacy and safety-related comparable outcome data, respectively. Statistical heterogeneity will be assessed by the p-value of chi-squared statistics and I2 statistics and explained by subgroup analysis and meta-regression. Publication bias will be assessed by funnel plots and Egger's test. The sensitivity analysis will repeat the meta-analysis for respective outcomes using assumptions alternative to that used in the preliminary meta-analysis and by dropping each study at a time.

RESULTS

A narrative reporting will ensue if a meta-analytic comparison is not possible.

CONCLUSIONS

Based on the contemporary literature, the proposed review will synthesize the evidence on how the efficacy and safety profile of high dose empagliflozin varies with its lower doses and placebo, respectively, in insulin-treated T1DM patients.

The Limited Role of Glucagon for Ketogenesis During Fasting or in Response to SGLT2 Inhibition

Glucagon is classically described as a counterregulatory hormone that plays an essential role in the protection against hypoglycemia. In addition to its role in the regulation of glucose metabolism, glucagon has been described to promote ketosis in the fasted state. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are a new class of glucose-lowering drugs that act primarily in the kidney, but some reports have described direct effects of SGLT2i on α-cells to stimulate glucagon secretion. Interestingly, SGLT2 inhibition also results in increased endogenous glucose production and ketone production, features common to glucagon action. Here, we directly test the ketogenic role of glucagon in mice, demonstrating that neither fasting- nor SGLT2i-induced ketosis is altered by interruption of glucagon signaling. Moreover, any effect of glucagon to stimulate ketogenesis is severely limited by its insulinotropic actions. Collectively, our data suggest that fasting-associated ketosis and the ketogenic effects of SGLT2 inhibitors occur almost entirely independent of glucagon.

Genetic ablation of SGLT2 function in mice impairs tissue mineral density but does not affect fracture resistance of bone

Selective sodium-dependent glucose co-transporter 2 inhibitors (SGLT2Is) are oral hypoglycemic medications utilized increasingly in the medical management of hyperglycemia among persons with type 2 diabetes (T2D). Despite favorable effects on cardiovascular events, specific SGLT2Is have been associated with an increased risk for atypical fracture and amputation in subgroups of the T2D population, a population that already has a higher risk for typical fragility fractures than the general population. To better understand the effect of SGLT2 blockade on skeletal integrity, independent of diabetes and its co-morbidities, we utilized the "Jimbee" mouse model of slc5a2 gene mutation to investigate the impact of lifelong SGLT2 loss-of-function on metabolic and skeletal phenotype. Jimbee mice maintained normal glucose homeostasis, but exhibited chronic polyuria, glucosuria and hypercalciuria. The Jimbee mutation negatively impacted appendicular growth of the femur and resulted in lower tissue mineral density of both cortical and trabecular bone of the femur mid-shaft and distal femur metaphysis, respectively. Several components of the Jimbee phenotype were characteristic only of male mice compared with female mice, including reductions: in body weight; in cortical area of the mid-shaft; and in trabecular thickness within the metaphysis. Despite these decrements, the strength of femur diaphysis in bending (cortical bone), which increased with age, and the strength of L6 vertebra in compression (primarily trabecular bone), which decreased with age, were not affected by the mutation. Moreover, the age-related decline in bone toughness was less for Jimbee mice, compared with control mice, such that by 49-50 weeks of age, Jimbee mice had significantly tougher femurs in bending than C57BL/6J mice. These results suggest that chronic blockade of SGLT2 in this model reduces the mineralization of bone but does not reduce its fracture resistance.

What have we learned about renal protection from the cardiovascular outcome trials and observational analyses with SGLT2 inhibitors?

Over the past 5 years, sodium-glucose cotransport 2 (SGLT2) inhibitors have been increasingly regarded as glycaemic agents with cardiovascular (CV) and renal protective effects. The CV benefits of SGLT2 inhibitors have been well established in patients with type 2 diabetes (T2D) and a range of CV comorbidities at baseline. Subsequently, the renal benefits of SGLT2 inhibitors were established in the CREDENCE trial, a dedicated renal outcome trial where canagliflozin reduced the primary composite renal outcome by 30%. In light of these trials, clinical practice guidelines have rapidly evolved, recommending the use of SGLT2 inhibitors as renal and cardioprotective agents in appropriate patient populations. Accordingly, it is important to have an in-depth understanding of the evidence underlying the use of SGLT2 inhibitors in patients with T2D based on published clinical trials and real-world evidence (RWE) studies, as well as information related to potential safety concerns. To accomplish this, we reviewed the evidence for renal protection and safety with SGLT2 inhibitors in the EMPA-REG OUTCOME, CANVAS Program and DECLARE-TIMI 58 CV safety trials, and in the growing body of evidence emerging from real-world studies. This body of work has shown that SGLT2 inhibitors reduce the risk of surrogate renal endpoints such as albuminuria and mitigate the risk of hard renal endpoints including doubling of serum creatinine and end-stage kidney disease in patients with T2D.

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

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

Efficacy and Safety of SGLT2 Inhibitors in Type 1 Diabetes After the Introduction of an Off-Label Use Protocol for Clinical Practice

Aims: We evaluated the real-life efficacy and safety of empagliflozin in combination with optimized insulin therapy in patients with type 1 diabetes (T1D). Methods: This was a prospective study, including 27 patients with T1D treated with insulin therapy to whom empagliflozin was added according to an off-label protocol approved for use in clinical practice. The primary end point was the change in HbA_1c 52 weeks after the addition of empagliflozin to insulin therapy. Blood pressure (BP), weight, and safety were also assessed. Results: At week 52, the addition of empagliflozin significantly reduced HbA_1c from 8.0% ± 0.7% to 7.2% ± 0.8% (P < 0.001). The mean percentage of time in range for capillary glucose monitoring increased from 50% to 62% (P = 0.008) in parallel to a -0.08 IU/(kg·day) reduction in insulin requirements (P = 0.031). There was also a reduction in the body weight (-8 kg) and in systolic BP from 134 to 127 mmHg (P < 0.001). The most commonly reported adverse events were genitourinary infections (10 episodes in 52 weeks of follow-up). One patient developed an episode of mild diabetic ketoacidosis that motivated empagliflozin withdrawal. No severe hypoglycemic events were registered. Conclusions: Our results suggested that the use of empagliflozin following a strict off-label protocol may represent an effective and safe option in real life among patients with T1D, improving metabolic control, and ameliorating some cardiovascular risk factors.

A potential diagnostic problem on the ICU: Euglycaemic diabetic Ketoacidosis associated with SGLT2 inhibition

Sodium glucose cotransporter 2 (SGLT2) inhibitors are the latest class of oral hypoglycaemic agents approved to treat type II diabetes. Their use is increasing and as such more patients will present to critical care whilst on this treatment. However, there have been several case reports of euglycaemic diabetic ketoacidosis associated with the use of these agents. Under such circumstances the blood glucose is often normal or only moderately elevated and hence the diagnosis may be delayed resulting in inappropriate therapy. In this review we describe a case of SGLT2 mediated ketoacidosis who presented to our intensive care unit, discuss the proposed pathophysiology behind this development of ketoacidosis as well as its potential prevention, management and treatment.

Adoption of New Glucose-Lowering Medications in the U.S.-The Case of SGLT2 Inhibitors: Nationwide Cohort Study

Background: High-quality diabetes care is evidence-based, timely, and equitable. Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are the most recently approved class of glucose-lowering medications with additional cardio- and renal-protective benefits and low risk of hypoglycemia. Cardiovascular and kidney disease are among the most common chronic diabetes complications, whereas hypoglycemia is the most prevalent adverse effect of glucose-lowering therapy. We examine the sociodemographic and clinical factors associated with early SGLT2i initiation and appropriateness of use based on contemporaneous scientific evidence. Materials and Methods: Retrospective analysis of medical and pharmacy claims data from OptumLabs® Data Warehouse for commercially insured and Medicare Advantage adult beneficiaries with diabetes types 1 and 2, who filled any glucose-lowering medication between January 1, 2013 and December 31, 2016. Demographic (age, sex, race, income), clinical (comorbidities), and insurance-related factors affecting first prescription for a SGLT2i were examined using multivariable logistic regression. Results: Among 1,054,727 adults with pharmacologically treated diabetes, 7.2% (n = 75,500) initiated a SGLT2i. Patients with prior myocardial infarction (MI) (odds ratio [OR]: 0.94, 95% confidence interval [CI]: 0.91-0.96), heart failure (HF) (OR: 0.93, 95% CI: 0.91-0.94), kidney disease (OR: 0.80, 95% CI: 0.78-0.81), and severe hypoglycemia (OR: 0.96, 95% CI: 0.94-0.98) were all less likely to start a SGLT2i; P < 0.001 for all. SGLT2i were also less likely to be started by patients ≥75 years (OR: 0.57, 95% CI: 0.55-0.59, vs. 18-44 years), Black patients (OR: 0.93, 95% CI: 0.91-0.95, vs. White), and those with Medicare Advantage insurance (OR: 0.63, 95% CI: 0.62-0.64, vs. commercial). Conclusions: Younger, healthier, non-Black patients with commercial health insurance were most likely to start taking SGLT2i. Patients with MI, HF, kidney disease, and prior hypoglycemia were less likely to use SGLT2i, despite evidence supporting their preferential use in these patients. Efforts to address this treatment-risk paradox may help improve health outcomes among patients with type 2 diabetes.

Efficacy and safety of ipragliflozin add-on therapy to insulin in Japanese patients with type 1 diabetes mellitus: A randomized, double-blind, phase 3 trial

AIM

To assess the efficacy and safety of once-daily ipragliflozin 50 mg versus placebo in Japanese people with type 1 diabetes mellitus (T1DM) inadequately controlled with insulin.

MATERIALS AND METHODS

We conducted a multicentre, double-blind, parallel-group, placebo-controlled phase 3 study. Participants (N = 175) were randomized (2:1) to receive once-daily ipragliflozin 50 mg (n = 115) or placebo (n = 60), combined with insulin, for 24 weeks. The primary endpoint was change in glycated haemoglobin (HbA1c); key secondary endpoints included change in insulin dose and body weight. Treatment-emergent adverse events (TEAEs) were evaluated.

RESULTS

The ipragliflozin group demonstrated a significant decrease in HbA1c from baseline to end of treatment versus the placebo group: adjusted mean difference (AMD) -3.8 mmol/mol (95% confidence interval [CI] -6.2, -1.5) or - 0.36% (95% CI -0.57, -0.14; P = 0.001). Significant reductions in total daily insulin dose (AMD -7.35 IU [95% CI -9.09, -5.61]; P < 0.001) and body weight (AMD -2.87 kg [95% CI -3.58, -2.16]; P < 0.001) were observed for the ipragliflozin group versus placebo. Two serious TEAEs occurred (major hypoglycaemia and abdominal abscess); both were in the placebo group. All other TEAEs were mild or moderate in severity. Four cases of study discontinuation occurred; three in the placebo group and one in the ipragliflozin group. No diabetic ketoacidosis was reported for any participant in this study.

CONCLUSIONS

Daily ipragliflozin 50 mg in combination with insulin significantly reduced HbA1c, daily insulin dose and body weight versus placebo in people with T1DM. No safety concerns were identified after 24 weeks of treatment. Overall, once-daily ipragliflozin 50 mg was both efficacious and well tolerated.

The Impact of Sotagliflozin on Renal Function, Albuminuria, Blood Pressure, and Hematocrit in Adults With Type 1 Diabetes

OBJECTIVE

In people with type 2 diabetes, sodium-glucose cotransporter 2 inhibitors (SGLT2i) reduce cardiovascular risk and progression of diabetic kidney disease. Our aim was to determine whether sotagliflozin (SOTA), a dual SGLT1i and SGLT2i, had favorable effects on clinical biomarkers suggestive of kidney protection in adults with type 1 diabetes.

RESEARCH DESIGN AND METHODS

In this 52-week pooled analysis, 1,575 adults enrolled in the inTandem1 and inTandem2 trials were randomized to SOTA 200 mg, 400 mg, or placebo in addition to optimized insulin therapy. Changes in cardiorenal biomarkers were assessed.

RESULTS

At 52 weeks, in response to SOTA 200 and 400 mg, the placebo-corrected least squares mean change from baseline in estimated glomerular filtration rate was -2.0 mL/min/1.73 m² (P = 0.010) and -0.5 mL/min/1.73 m² (P = 0.52), respectively. Systolic blood pressure difference was -2.9 and -3.6 mmHg (P < 0.0001 for both); diastolic blood pressure changed by -1.4 (P = 0.0033) and -1.6 mmHg (P = 0.0008). In participants with baseline urinary albumin-to-creatinine ratio (UACR) ≥30 mg/g, UACR decreased by 23.7% (P = 0.054) and 18.3% (P = 0.18) for SOTA 200 and SOTA 400 mg, respectively, versus placebo. Increases in serum albumin and hematocrit and reductions in uric acid were observed throughout 52 weeks with both SOTA doses.

CONCLUSIONS

SOTA was associated with short- and long-term renal hemodynamic changes, which were similar to those seen with SGLT2i in type 2 diabetes. Further investigation around cardiorenal effects of SOTA in people with type 1 diabetes is justified.

Effects of sodium-glucose cotransporter (SGLT) inhibitors in addition to insulin therapy on glucose control and safety outcomes in adults with type 1 diabetes: A meta-analysis of randomized controlled trials

Sodium-glucose cotransporter (SGLT) inhibitors added to insulin therapy have been proposed as treatment strategy for type 1 diabetes (T1D). We thus conducted a meta-analysis of randomized controlled trials (RCTs) to assess the efficacy and adverse effects of this combination in T1D. We searched the PubMed, EMBASE, and Cochrane Library databases and ClinicalTrials.gov for RCTs. Statistical analyses were performed using STATA 15. Ten eligible placebo-controlled trials involving 5961 patients were included. Compared with placebo, SGLT inhibitors were associated with a reduction in HbA1c of -0.39% (95% CI, -0.43 to -0.36), an improved mean amplitude of glucose excursion (MAGE) of -14.81 mg/dL (95% CI, -19.08 to -10.54), and a reduction in body weight of -3.47% (95% CI, -3.78 to -3.16), as well as no increased relative risk of hypoglycaemia (1.01; 95% CI, 0.99-1.02) or severe hypoglycaemia (0.91; 95% CI, 0.77-1.07). SGLT inhibitors decreased fasting plasma glucose and insulin requirement but increased the risk of genital infection (3.57; 95% CI, 2.97-4.29) and diabetic ketoacidosis (3.11; 95% CI, 2.11-4.58). However, the very low dose empagliflozin (2.5 mg) did not increase the risk of diabetic ketoacidosis (risk ratio [RR] 0.67; 95% CI, 0.11-3.95). SGLT inhibitors had no effect on overall adverse events, urinary tract infection, or bone fracture but slightly increased the risk of serious adverse events (1.35; 95% CI, 1.16-1.58), severe adverse events (1.84; 95% CI, 1.20-2.84), adverse events leading to discontinuation (1.50; 95% CI, 1.22-1.84), drug-related adverse events (1.78; 95% CI, 1.44-2.19), and diarrhoea (1.54; 95% CI, 1.15-2.05). Although adverse events exist, the available data provide evidence that the combination of SGLT inhibitors with basal insulin treatment is beneficial in patients with T1D.

Dapagliflozin (SGLT2-i) induced euglycaemic diabetic ketoacidosis

Sodium glucose co-transporter-2 inhibitors (SGLT2-i) have become a popular therapeutic strategy in the management of hyperglycaemia in type 2 diabetes mellitus. The primary site of action of SGLT2-i is at the proximal renal convoluted tubule. They work by blocking SGLT2 receptors, sodium-dependent glucose co-transport molecules, which in turn prevents glucose reabsorption, facilitating glucosuria, improving glycaemic control as well as a moderate degree of weight loss. We report the case of a 51-year-old woman admitted to the acute medical unit with abdominal pain and vomiting, who was diagnosed with euglycaemic diabetic ketoacidosis secondary to recent initiation of an SGLT2-i medication (dapagliflozin). Clinicians should be aware of this rare side effect of SGLT2-i, to circumvent delays in patient management.

Effects of sodium-glucose cotransporter 2 inhibitor (dapagliflozin) on food intake and plasma fibroblast growth factor 21 levels in type 2 diabetes patients

The objective of this study was to investigate whether sodium-glucose cotransporter 2 inhibitors (SGLT2i) treatment in patients with type 2 diabetes induced compensatory hyperphagia by reducing fibroblast growth factor 21 (FGF21) secretion. This prospective study was performed in 26 type 2 diabetes patients treated with dapagliflozin (5 mg/day). Hormonal factors associated with glucose metabolism, dietary intakes estimated by brief self-administered diet-history questionnaire (BDHQ), body weight (BW), and body composition were measured at baseline, and 4 and 12 weeks after dapagliflozin. At 12 weeks, HbA1c levels and BW decreased significantly (both p < 0.0001). BMI at baseline was predictive to baseline log₁₀ (FGF21) (p = 0.037). This study showed no change in FGF21, but insulin and glucagon levels decreased significantly (both p < 0.05). Although hyperphagia was found in 10 patients (38.5%), defining hyperphagia as >20% increase in carbohydrate intake, dapagliflozin treatment induced no hyperphagia, when analyzed by all subjects, and there was no significant association between changes in FGF21 levels and carbohydrate intake. On the other hand, a positive correlation between changes in FGF21 levels or carbohydrate intake and BW was observed (both p < 0.005). Taken together, this study demonstrates that the intervention to maintain the reduced levels in FGF21 is beneficial for BW reduction in type 2 diabetes patients treated with SGLT2i.

Sustained fasting glucose oxidation and postprandial lipid oxidation associated with reduced insulin dose in type 2 diabetes with sodium-glucose cotransporter 2 inhibitor: A randomized, open-label, prospective study

AIMS/INTRODUCTION

Hyperglycemia impairs energy substrate oxidation as a result of glucotoxicity. We examined whether the reduction of plasma glucose using a sodium-glucose cotransporter 2 inhibitor, in inpatient diabetes management, has any effect on: (i) treatment period and basal-bolus dosage of insulin that achieve euglycemia; (ii) fasting/postprandial energy expenditure (EE); and (iii) energy substrate oxidation.

MATERIALS AND METHODS

This was a randomized, open-label, 7-day prospective study. Participants were type 2 diabetes patients with hyperglycemia, aged >20 years, with glycated hemoglobin >10%, daily mean preprandial blood glucose >11 mmol/L (200 mg/dL) and no previous antidiabetic medication. A total of 18 type 2 diabetes patients were randomized (1:1) to basal-bolus insulin titration algorithm (INS) alone or INS + dapagliflozin 5 mg/day (INS/DAPA). The main outcome measures were total daily insulin dose to achieve euglycemia, as well as EE and respiratory quotient during fasting and postprandial states, measured by indirect calorimetry.

RESULTS

The rate of euglycemia was higher in the INS/DAPA compared with INS group (100 vs 55.6%, P = 0.04), whereas the total daily dose of insulin was 19% lower and was accompanied by a decreased basal-bolus ratio (P = 0.02). Fasting and postprandial EE elevation were similar in both groups. The post-treatment fasting respiratory quotient significantly increased in the INS/DAPA group (0.72 ± 0.05 vs 0.79 ± 0.08, P = 0.04), and the postprandial respiratory quotient elevation was abolished; the opposite trend was observed in the INS group (P < 0.02).

CONCLUSIONS

INS/DAPA sustained fasting carbohydrate oxidation, postprandial lipid-derived EE (failed to increase carbohydrate-derived EE) and reduced basal insulin requirement might be related to further bodyweight loss.

CLINICAL TRIAL REGISTRY

National University Hospital Medical Information Network UMIN000018997.

Sodium-Glucose Cotransporters as Potential Therapeutic Targets in Patients With Type 1 Diabetes Mellitus: An Update on Phase 3 Clinical Trial Data

Objective: To review phase 3 trials of sodium-glucose cotransporter (SGLT) inhibitors in type 1 diabetes mellitus (T1DM) patients. Data Sources: A literature search of Ovid MEDLINE databases (1946 through May 17, 2019) limited to English-language human clinical trials was conducted using the following terms: sodium-glucose transporter 2 inhibitors, canagliflozin, dapagliflozin, empagliflozin, sotagliflozin, ertugliflozin, ipragliflozin, or remogliflozin combined with type 1 diabetes mellitus. Results were verified via Google Scholar and clinicaltrials.gov. Study Selection and Data Extraction: Articles were included if they were phase 3 trials in adults with T1DM. Data Synthesis: Phase 3 trials are available for dapagliflozin, empagliflozin, and sotagliflozin. All 3 drugs demonstrated statistically significant reductions in hemoglobin A1C, weight, and total daily insulin dose without an increased risk of hypoglycemia in up to 52 weeks of therapy. The incidence of diabetic ketoacidosis (DKA) was higher in patients on a SGLT inhibitor at all doses, with the exception of empagliflozin 2.5 mg (0.8% vs 1.2% with placebo). Relevance to Patient Care and Clinical Practice: SGLT inhibitors are potential adjuncts to insulin in T1DM patients, providing clinically meaningful benefits. Regulatory bodies have either approved or are reviewing these agents for use in T1DM. Clinicians should be familiar with the DKA risk associated with SGLT inhibitors and utilize DKA risk-mitigation strategies. Empagliflozin 2.5 mg warrants additional investigation given its efficacy without an increased incidence of DKA. Conclusions: Phase 3 trial data of SGLT inhibitors provide evidence for sustained efficacy in T1DM patients. Appropriate patient selection for therapy and routine monitoring are essential to minimize associated risks.