Sodium-glucose cotransporter 2 inhibition in non-diabetic kidney disease

Cardio-renal protective effect and safety of sodium-glucose cotransporter 2 inhibitors for chronic kidney disease patients with eGFR < 60 mL/min/1.73 m2: a systematic review and meta-analysis

OBJECTIVE

This meta-analysis was designed to investigate cardio-renal outcomes and safety of sodium-glucose cotransporter-2 inhibitors (SGLT2i) as a therapeutic option among chronic kidney disease(CKD) patients with GFR < 60 mL/min/1.73 m2, regardless of their diabetic status.

METHOD

We conducted a full-scale search from MEDLINE, EMBASE and the Cochrane Library database to identify eligible studies up to Jun 2024. All randomized controlled trials (RCTs) comparing cardio-renal outcomes and/or safety of SGLT2i in CKD patients with eGFR < 60 mL/min/1.73 m2 were involved. The relative risk (RR) and 95% confidence interval (CI) for primary outcomes and adverse events were computed by random-effects mode. We used I2 statistic to analyze heterogeneity. Publication bias was assessed by Egger's test.

RESULTS

Our study incorporated 17 RCTS, including 27,928 patients. In CKD patients with eGFR < 60 mL/min/1.73 m2, SGLT2i decreased risks of cardiovascular events (seven studies, 17,355 participants, RR 0.77, 95% CI 0.70-0.84), hospitalization for heart failure (HHF) (seven studies, 17,869 participants, RR 0.73, 95% CI 0.65-0.82), cardiovascular death (eight studies, 23,079 participants, RR 0.81, 95% CI 0.74 to 0.88) and renal composite outcomes (eight studies, 22,525 participants, RR 0.70, 95% CI 0.61-0.80) with lower risks of any serious adverse effects(fourteen studies, 19,654 participants, RR 0.91, 95% CI 0.87-0.95), hypoglycemia (nine studies, 16,412 participants, RR 0.91, 95% CI 0.84-0.98), hyperkalemia (four studies, 2693 participants, RR 0.68, 95% CI 0.51-0.93) and acute renal injury (five studies, 5424 participants, RR 0.79, 95% CI 0.65-0.95) compared to placebo. SGLT2i also slowed eGFR decline (total slopes: five studies, 10,370 participants, mean difference 1.17, 95%CI 0.86-1.49; chronic slopes: four studies, 8459 participants, mean difference 2.12, 95%CI 1.64-2.61). Further subgroup analyses revealed that SGLT2i decreased relative risks of cardiovascular outcomes(three studies, 1075 participants, RR 0.76, 95% CI 0.54-0.82), HHF(four studies, 1280 participants, RR 0.74, 95% CI 0.55-1.00) and renal composite outcomes (six studies,4375 participants, RR 0.78, 95% CI 0.68-0.88) with no increased adverse events in the CKD 4 patients.

CONCLUSIONS

SGLT2i significantly improved cardio-renal outcomes and were generally safe in CKD patients with eGFR < 60 mL/min/1.73 m2 and with eGFR < 30 mL/min/1.73 m2. Future large-scale RCTs are needed to confirm the robustness of these results.

SGLT2 inhibitors in peritoneal dialysis: a promising frontier toward improved patient outcomes

Peritoneal dialysis (PD) stands as an important modality among kidney replacement therapies for end-stage kidney disease, offering patients remarkable flexibility and autonomy. Despite its widespread use, challenges such as glucose-related complications, peritoneal membrane fibrosis, declining renal function, and cardiovascular risks persist, necessitating innovative therapeutic approaches. Sodium–glucose cotransporter 2 (SGLT2) inhibitors, originally developed for treating type 2 diabetes mellitus, have recently shown promise as add-on therapy for patients with diabetic and non-diabetic chronic kidney disease (CKD), even in advanced stages. This review describes the potential role of SGLT2 inhibitors as a breakthrough therapeutic option in PD, emphasizing their ability to address unmet clinical needs and improve patient outcomes. The multiple effects of SGLT2 inhibitors in CKD, including metabolic modulation, antihypertensive, diuretic, anemia-reducing, antioxidant, and antiinflammatory properties, are reviewed in the context of PD challenges. Additionally, the potentially protective influence of SGLT2 inhibitors on the integrity of the peritoneal membrane and the transport of solutes and water in the peritoneum are emphasized. Despite these encouraging results, the paper highlights the potential risks associated with SGLT2 inhibitors in PD and emphasizes the need for cautious and thorough investigation of dosing, long-term safety considerations, and patient-specific factors through comprehensive clinical trials. Looking forward, the review argues for well-designed studies to evaluate the expanded safety profile of SGLT2 inhibitors in PD, with particular attention paid to peritoneal membrane integrity and overall patient outcomes.

Sex-dependent effects of Canagliflozin on kidney protection in mice with combined hypertension-type 1 diabetes

Canagliflozin (CANA) is a sodium-glucose cotransporter 2 (SGLT2) inhibitor with blood glucose lowering effects. CANA also promotes kidney protection in patients with cardiovascular diseases and type 2 diabetes (T2D), as well as in normoglycemic patients with hypertension or heart failure. Clinical studies, although conduct in both sexes, do not report sex-dependent differences in T2DM treated with CANA. However, the impact of CANA in type 1 diabetes, as well in sex-dependent outcomes in such cohort needs further understanding. To analyze the effects of CANA in mice with combined hypertension and type 1 diabetes, diabetes was induced by STZ injection (5 days, 50mg/kg/day) in both male and female 8 weeks old genetic hypertensive mice (Lin), whereas the control (Lin) received 0.1M sodium citrate injections. 8 weeks after STZ. Mice were fed either regular or CANA-infused diet for 4 weeks. 8 weeks after STZ, hyperglycemia was present in both male and female mice. CANA reversed BG increase mice fed regular diet. Male LinSTZ mice had elevated water intake, urine output, urinary albumin to creatinine ratio (ACR), kidney lesion score, and creatinine clearance compared to the Lin control group. Kidney injury was improved in male LinSTZ + CANA group in male mice. Water intake and urine output were not statistically significantly different in female LinSTZ compared to female LinSTZ+ CANA. Moreover, CANA did not improve kidney injury in female mice, showing no effect in creatinine clearance, lesion score and fibrosis when compared to LinSTZ fed regular diet. Here we show that Canagliflozin might exert different kidney protection effects in male compared to female mice with hypertension and type 1 diabetes. Sex-dimorphisms were previously found in the pathophysiology of diabetes induced by STZ. Therefore, we highlight the importance of in-depth investigation on sex-dependent effects of CANA, taking in consideration the unique characteristics of disease progression for each sex.

SGLT2 Inhibitors: The Sweet Success for Kidneys

Sodium-glucose cotransporter-2 inhibitors (SGLT2 inhibitors) were originally developed as antidiabetic agents, with cardiovascular (CV) outcome trials demonstrating improved CV outcomes in patients with type 2 diabetes mellitus (T2D). Secondary analyses of CV outcome trials and later dedicated kidney outcome trials consistently reported improved kidney-related outcomes independent of T2D status and across a range of kidney function and albuminuria. Importantly, SGLT2 inhibitors are generally safe and well tolerated, with clinical trials and real-world analyses demonstrating a decrease in the risk of acute kidney injury. The kidney protective effects of SGLT2 inhibitors generally extend across different members of the class, possibly on the basis of hemodynamic, metabolic, anti-inflammatory, and antifibrotic mechanisms. In this review, we summarize the effects of SGLT2 inhibitors on kidney outcomes in diverse patient populations.

Cardiorenal protection of SGLT2 inhibitors—Perspectives from metabolic reprogramming

Sodium-glucose co-transporter 2 (SGLT2) inhibitors, initially developed as a novel class of anti-hyperglycaemic drugs, have been shown to significantly improve metabolic indicators and protect the kidneys and heart of patients with or without type 2 diabetes mellitus. The possible mechanisms mediating these unexpected cardiorenal benefits are being extensively investigated because they cannot solely be attributed to improvements in glycaemic control. Notably, emerging data indicate that metabolic reprogramming is involved in the progression of cardiorenal metabolic diseases. SGLT2 inhibitors reprogram systemic metabolism to a fasting-like metabolic paradigm, involving the metabolic switch from carbohydrates to other energetic substrates and regulation of the related nutrient-sensing pathways, which might explain some of their cardiorenal protective effects. In this review, we will focus on the current understanding of cardiorenal protection by SGLT2 inhibitors, specifically its relevance to metabolic reprogramming.

The Pathophysiological Basis of Diabetic Kidney Protection by Inhibition of SGLT2 and SGLT1

SGLT2 inhibitors can protect the kidneys of patients with and without type 2 diabetes mellitus and slow the progression towards end-stage kidney disease. Blocking tubular SGLT2 and spilling glucose into the urine, which triggers a metabolic counter-regulation similar to fasting, provides unique benefits, not only as an anti-hyperglycemic strategy. These include a low hypoglycemia risk and a shift from carbohydrate to lipid utilization and mild ketogenesis, thereby reducing body weight and providing an additional energy source. SGLT2 inhibitors counteract hyperreabsorption in the early proximal tubule, which acutely lowers glomerular pressure and filtration and thereby reduces the physical stress on the filtration barrier, the filtration of tubule-toxic compounds, and the oxygen demand for tubular reabsorption. This improves cortical oxygenation, which, together with lesser tubular gluco-toxicity and improved mitochondrial function and autophagy, can reduce pro-inflammatory, pro-senescence, and pro-fibrotic signaling and preserve tubular function and GFR in the long-term. By shifting transport downstream, SGLT2 inhibitors more equally distribute the transport burden along the nephron and may mimic systemic hypoxia to stimulate erythropoiesis, which improves oxygen delivery to the kidney and other organs. SGLT1 inhibition improves glucose homeostasis by delaying intestinal glucose absorption and by increasing the release of gastrointestinal incretins. Combined SGLT1 and SGLT2 inhibition has additive effects on renal glucose excretion and blood glucose control. SGLT1 in the macula densa senses luminal glucose, which affects glomerular hemodynamics and has implications for blood pressure control. More studies are needed to better define the therapeutic potential of SGLT1 inhibition to protect the kidney, alone or in combination with SGLT2 inhibition.

Aryl Hydrocarbon Receptor Mechanisms Affecting Chronic Kidney Disease

The aryl hydrocarbon receptor (AHR) is a basic helix-loop-helix transcription factor that binds diverse endogenous and xenobiotic ligands, which regulate AHR stability, transcriptional activity, and cell signaling. AHR activity is strongly implicated throughout the course of chronic kidney disease (CKD). Many diverse organic molecules bind and activate AHR and these ligands are reported to either promote glomerular and tubular damage or protect against kidney injury. AHR crosstalk with estrogen, peroxisome proliferator-activated receptor-γ, and NF-κB pathways may contribute to the diversity of AHR responses during the various forms and stages of CKD. The roles of AHR in kidney fibrosis, metabolism and the renin angiotensin system are described to offer insight into CKD pathogenesis and therapies.