The major molecular mechanisms mediating the renoprotective effects of SGLT2 inhibitors: An update

Peter WL, Shubrook JH. Type 2 Diabetes and Chronic Kidney Disease: An Opportunity for Pharmacists to Improve Outcomes

Chronic kidney disease (CKD) is an important contributor to end-stage kidney disease, cardiovascular disease, and death in people with type 2 diabetes (T2D), but current evidence suggests that diagnosis and treatment are often not optimized. This review examines gaps in care for patients with CKD and how pharmacist interventions can mitigate these gaps. We conducted a PubMed search for published articles reporting on real-world CKD management practice and compared the findings with current recommendations. We find that adherence to guidelines on screening for CKD in patients with T2D is poor with particularly low rates of testing for albuminuria. When CKD is diagnosed, the prescription of recommended heart-kidney protective therapies is underutilized, possibly due to issues around treatment complexity and safety concerns. Cost and access are barriers to the prescription of newer therapies and treatment is dependent on racial, ethnic, and socioeconomic factors. Rates of nephrologist referrals for difficult cases are low in part due to limitations of information and communication between specialties. We believe that pharmacists can play a vital role in improving outcomes for patients with CKD and T2D and support the cost-effective use of healthcare resources through the provision of comprehensive medication management as part of a multidisciplinary team. The Advancing Kidney Health through Optimal Medication Management initiative supports the involvement of pharmacists across healthcare systems to ensure that comprehensive medication management can be optimally implemented.

Nanoparticles with SGLT2 inhibitory activity: Possible benefits and future

AIM

Nano-drug delivery is a rapidly growing approach in medicine that helps design and develop newer forms of drugs with more efficacy and lower adverse effects. Sodium-glucose cotransporter-2 inhibitors are an emerging class of antidiabetic agents that reduce the blood glucose levels by damping glucose reabsorption in renal proximal tubules.

METHODS AND RESULTS

This mechanism might be followed by some adverse effects that could be prevented by nano-drug delivery. Although we have still limited evidence about nanoforms of sodium-glucose cotransporter-2 inhibitors, current knowledge strongly suggests that nanotechnology can help us design more effective drugs with lower side effects. In recent years, several studies have explored the possible benefits of nanoforms of sodium-glucose cotransporter-2 inhibitors. However, clinical trials are yet to be conducted.

CONCLUSION

In the current review, we present the latest findings on the development and benefits of nanoforms of sodium-glucose cotransporter-2 inhibitors.

Impact of sodium-glucose cotransporter-2 inhibitors on kidney outcomes in type 2 diabetes: A tertiary center experience

BACKGROUND

Diabetic nephropathy (DN) is a complication of chronic hyperglycemia associated with diabetes mellitus (DM). Several studies have demonstrated the positive impact of sodium-glucose cotransporter-2 (SGLT2) inhibitors on kidney outcomes. The objective of the study was to evaluate the effects of dapagliflozin, an SGLT2 inhibitor, on kidney outcomes in Saudi patients with type 2 DM.

MATERIALS AND METHODS

Study included all Saudi patients with type 2 DM who visited our center from August 1, 2021, to July 31, 2022, and had been on dapagliflozin for at least 3 months. Data was abstracted through chart review for all patients included in the study. Paired t-test or Wilcoxon signed-rank test were used to compare the results before and after treatment for continuous variables and the McNemar test was used to compare the results for categorical data.

RESULTS

Study included 184 Saudi patients with type 2 diabetes with a mean age of 61.32 years (SD=9.37). Dapagliflozin 10 mg/day significantly reduced hemoglobin A1C (HbA1C) from a mean (SD) of 9.00 to 8.40 (P < 0.001). Among a subgroup of patients with significant proteinuria (n = 83), dapagliflozin significantly reduced ACR from a median of 93.1 to 64.9 mg/g (P = 0.001). Following treatment, the estimated glomerular filtration rate improved from a mean of 69.83 to 71.68 mL/min and the mean arterial pressure (MAP) fell from 90.03 to 89.06 mmHg, both were not statistically significant. Despite a statistically insignificant increase in the episodes of urinary tract infections (UTIs), the hospitalization rate declined. No episodes of amputations or ketoacidosis occurred during the study period.

CONCLUSION

SGLT2 inhibitors had beneficial effects among Saudi patients with type 2 diabetes by improving diabetic control and lowering proteinuria. Dapagliflozin did not result in significant harm, including UTIs, amputations, and ketoacidosis.

Impact of tofogliflozin on hepatic outcomes: a systematic review

PURPOSE

Studies have demonstrated a high prevalence of non-alcoholic fatty liver disease (NAFLD) in type 2 diabetes mellitus (T2DM) patients. The aim was to review the effect of tofogliflozin on hepatic outcomes in T2DM patients.

METHODS

A literature search in PubMed, Science Direct and Cochrane Central Register of Controlled Trials was conducted for randomised clinical trials of tofogliflozin by applying predetermined inclusion and exclusion criteria.

RESULTS

A total number of four randomised clinical trials, including 226 subjects, were included in the review. There was a significant decrease in aspartate aminotransferase (AST) and alanine transaminase (ALT) levels in the tofogliflozin group as compared to the control or active comparator groups. Additionally, gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP) and magnetic resonance imaging proton density fat fraction (MRI-PDFF) levels were also significantly decreased in the tofogliflozin group. However, no significant difference was observed in levels of adiponectin.

CONCLUSION

Overall, an improvement in levels of hepatic parameters was observed in T2DM patients with concurrent liver disorders. However, a large number of clinical trials are needed to prove the efficacy of tofogliflozin on hepatic outcomes in patients with T2DM.

Mechanistic View on the Effects of SGLT2 Inhibitors on Lipid Metabolism in Diabetic Milieu

Chronic hyperglycemia induces pathophysiologic pathways with negative effects on the metabolism of most substrates as well as lipids and lipoproteins, and thereby induces dyslipidemia. Thus, the diabetic milieu is commonly accompanied by different levels of atherogenic dyslipidemia, which is per se a major risk factor for subsequent complications such as atherosclerosis, coronary heart disease, acute myocardial infarction, ischemic stroke, and nephropathy. Therefore, readjusting lipid metabolism in the diabetic milieu is a major goal for preventing dyslipidemia-induced complications. Sodium-glucose cotransporter-2 (SGLT2) inhibitors are a class of relatively newly introduced antidiabetes drugs (including empagliflozin, canagliflozin, dapagliflozin, etc.) with potent hypoglycemic effects and can reduce blood glucose by inducing glycosuria. However, recent evidence suggests that they could also provide extra-glycemic benefits in lipid metabolism. It seems that they can increase fat burning and lipolysis, normalizing the lipid metabolism and preventing or improving dyslipidemia. Nevertheless, the exact mechanisms involved in this process are not well-understood. In this review, we tried to explain how these drugs could regulate lipid homeostasis and we presented the possible involved cellular pathways supported by clinical evidence.

Mechanisms of antidiabetic drugs and cholesterol efflux: a clinical perspective

Reverse cholesterol transport (RCT) is a physiological process that reduces excess cholesterol in the body. Cholesterol efflux (CE), an important step in RCT, is mainly mediated by ATP-binding cassette transporters A1 and G1 and has a significant role in atheroprotection. Moreover, impairments in CE can lead to the development of diabetes and fatty liver disease. In this review, we summarize the possible effects of hypoglycemic agents on CE and how this might influence atherosclerosis and dyslipidemia-related pathologies. Newer antidiabetic agents could have significant potential for targeting CE and preventing or alleviating atherosclerosis, obesity, and liver steatosis, and simultaneously improving insulin secretion. However, more research is warranted to interpret the clinical relevance of these data.

Impacts of Sodium/Glucose Cotransporter-2 Inhibitors on Circulating Uric Acid Concentrations: A Systematic Review and Meta-Analysis

BACKGROUND

Several trials have assessed the antihyperglycemic effects of sodium/glucose cotransporter-2 inhibitors (SGLT2i) in patients with type 2 diabetes mellitus (T2DM). We conducted a quantitative analysis to assess the impact of SGLT2is on serum uric acid (SUA) in patients with T2DM.

METHODS

Placebo-controlled trials published before 13 August 2021 were identified by searching PubMed, Embase, Web of Science, and Scopus. The intervention group received SGLT2i as monotherapy or add-on treatment, and the control group received a placebo that was replaced with SGLT2i. Clinical trials providing changes in SUA were included. The mean change of SUA, glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), and body weight were calculated (PROSPERO CRD42021287019).

RESULTS

After screening of 1172 papers, 59 papers were included in the systematic review. A total of 55 trials (122 groups) of 7 types of SGLT2i on patients with T2DM were eligible for meta-analysis. All SGLT2is significantly decreased SUA levels compared with the placebo groups: empagliflozin mean difference (MD) = -40.98 μmol/L, 95% CI [-47.63, -34.32], dapagliflozin MD = -35.17 μmol/L, 95% CI [-39.68, -30.66], canagliflozin MD = -36.27 μmol/L, 95% CI [-41.62, -30.93], luseogliflozin MD = -24.269 μmol/L, 95% CI [-33.31, -15.22], tofogliflozin MD = -19.47 μmol/L, 95% CI [-27.40, -11.55], and ipragliflozin MD = -18.85 μmol/L, 95% CI [-27.20, -10.49]. SGLT2i also decreased FPG, body weight, and HbA1c levels. SUA reduction persisted during long-term treatment with SGLT2i (except for empagliflozin), while the SUA reduction was affected by the duration of diabetes.

CONCLUSIONS

SGLT2i can be a valid therapeutic strategy for patients with T2DM and comorbid hyperuricemia. Besides reducing FPG, body weight, and HbA1c, SGLT2i can significantly decrease SUA levels compared to placebo (Total MD = -34.07 μmol/L, 95% CI [-37.00, -31.14]).

Management of chronic kidney disease in type 2 diabetes: screening, diagnosis and treatment goals, and recommendations

Patients with chronic kidney disease (CKD) and type 2 diabetes (T2D) are at high risk of CKD progression and cardiovascular (CV) disease. Prevalence of CKD in patients with T2D is currently around 40% and continues to grow. The increasing number of people with CKD and T2D will ultimately have a significant impact upon health resource use and costs of care for people with T2D. Management of CKD in patients with T2D aims to preserve kidney function to reduce the risk of end-stage kidney disease, CV events, and mortality. Evidence-based recommendations for the treatment of patients with CKD and T2D are provided by several international and national organizations and recommend several lifestyle and pharmacological approaches to help prevent or delay the progression of CKD in patients with T2D. Guidelines include regular screening of patients with T2D for CKD using spot urine albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (at least annually and at least twice a year if UACR >300 mg/g). Additionally, assessment of vascular complications, together with interventions designed to improve glycemic control and lipid levels, maintain healthy body weight, and optimize blood pressure should be performed. Medications shown to slow progression of CKD include renin-angiotensin system inhibitors, sodium-glucose cotransporter-2 inhibitors, glucagon-like peptide 1 receptor agonists, and, more recently, selective, non-steroidal mineralocorticoid receptor antagonists. This review highlights the ongoing challenges facing primary care providers in the management of CKD in patients with T2D including the consideration of comorbidities, adoption of new treatment options, and implementation of individualized care. Achieving consensus for optimal treatment of this disease is critical in providing consistent and appropriate care for all patients. Strategies to improve outcomes should also include use of clear referral criteria, use of a multi-disciplinary approach, and patient education.

Renoprotective mechanisms of sodium-glucose co-transporter 2 (SGLT2) inhibitors against the progression of diabetic kidney disease

Sodium-glucose co-transporter 2 inhibitors (SGLT2-Is) have emerged as a promising class of antidiabetic drugs with cardioprotective and renoprotective effects in patients with type 2 diabetes (T2D). The sodium-glucose co-transporters 1 and 2 (SGLT 1 and SGLT2) located in the renal proximal tubules are responsible for glucose reabsorption from the glomerular filtrate back into the systemic circulation. Inhibition of SGLT2, which accounts for about 90% of the glucose reabsorption, leads to a significant reduction in blood glucose levels and a concomitant increase in the urinary excretion of glucose (glycosuria). Multiple mechanisms contribute to the nephroprotective effects of SGLT2-Is in T2D patients. These include: (1) Restoration of the tubuloglomerular feedback by increasing sodium delivery at macula densa, leading to afferent arteriolar constriction and reduced glomerular hyperfiltration, (2) Decreased activation of the intra-renal renin-angiotensin-aldosterone system, which also contributes to reducing glomerular hyperfiltration, (3) Increased production of ketone bodies, which serves as an alternate fuel for adenosine triphosphate production in mitochondria, which helps in attenuating inflammation, and (4) Protection against hypoxia, oxidative stress, and fibrosis. This review elaborates on the key mechanisms that underlie the nephroprotective effects and the adverse effects of SGLT2-Is in T2D patients with progressive diabetic kidney disease.

Dapagliflozin, an SGLT2 inhibitor, ameliorates acetic acid-induced colitis in rats by targeting NFκB/AMPK/NLRP3 axis

The development of effective treatment strategies has been hindered by the complex pathogenesis of ulcerative colitis (UC). UC patients treated with current therapeutic approaches experienced either treatment failure or suffered excessive adverse reactions. Overactivity of NLRP3 inflammasome enhances inflammation, resulting in aggravation of colonic damage. We were interested in exploring, for the first time, the potential coloprotective effect of dapagliflozin (DPZ) on acetic acid-induced UC in rats in comparison with 5-ASA. DPZ improved histologic and macroscopic features of colon tissues and prolonged survival of UC rats. DPZ also prevented colon shortening and declined disease activity. Additionally, DPZ lessened colon tissue neutrophil content and improved antioxidant defense machinery. Further, DPZ specifically declined the colonic inflammatory marker IL-6 and upregulated the anti-inflammatory cytokine IL-10. The pyroptosis process is constrained in consequence of the repressed caspase-1 activity and caspase-1-dependent release of the bioactive cytokines IL-1β and IL-18. These protective effects might be attributed to that DPZ on the one hand, prevented the priming step (signal 1) of NLRP3 inflammasome activation as revealed by modulating NFκB/AMPK interplay and on the other hand, inhibited the activation step (signal 2) as indicated by interrupting NLRP3/caspase-1 signaling. Since DPZ was found to be safe and well tolerated by healthy volunteers with no evidence of hypoglycemia, it might show promise in the future management of UC. However, further investigations are warranted to confirm the reversal of injury and that the coloprotective effect is substantial.

Diabetic proximal tubulopathy: Can we mimic the disease for in vitro screening of SGLT inhibitors?

Diabetic kidney disease (DKD) is the foremost cause of renal failure. While the glomeruli are severely affected in the course of the disease, the main determinant for disease progression is the tubulointerstitial compartment. DKD does not develop in the absence of hyperglycemia. Since the proximal tubule is the major player in glucose reabsorption, it has been widely studied as a therapeutic target for the development of new therapies. Currently, there are several proximal tubule cell lines available, being the human kidney-2 (HK-2) and human kidney clone-8 (HKC-8) cell lines the ones widely used for studying mechanisms of DKD. Studies in these models have pushed forward the understanding on how DKD unravels, however, these cell culture models possess limitations that hamper research, including lack of transporters and dedifferentiation. The sodium-glucose cotransporters (SGLT) are identified as key players in glucose reabsorption and pharmacological inhibitors have shown to be beneficial for the long-term clinical outcome in DKD. However, their mechanism of action has, as of yet, not been fully elucidated. To comprehend the protective effects of SGLT inhibitors, it is essential to understand the complete functional, structural, and molecular features of the disease, which until now have been difficult to recapitulate. This review addresses the molecular events of diabetic proximal tubulopathy. In addition, we evaluate the protective role of SGLT inhibitors in cardiovascular and renal outcomes, and provide an overview of various in vitro models mimicking diabetic proximal tubulopathy used so far. Finally, new insights on advanced in vitro systems to surpass past limitations are postulated.

Therapeutic Targeting of SGLT2: A New Era in the Treatment of Diabetes and Diabetic Kidney Disease

As the prevalence of diabetic kidney disease (DKD) continues to rise, so does the need for a novel therapeutic modality that can control and slow its progression to end-stage renal disease. The advent of sodium-glucose cotransporter-2 (SGLT2) inhibitors has provided a major advancement for the treatment of DKD. However, there still remains insufficient understanding of the mechanism of action and effectiveness of this drug, and as a result, its use has been very limited. Burgeoning evidence suggests that the SGLT2 inhibitors possess renal protective activities that are able to lower glycemic levels, improve blood pressure/hemodynamics, cause bodyweight loss, mitigate oxidative stress, exert anti-inflammatory and anti-fibrotic effects, reduce urinary albumin excretion, lower uric acid levels, diminish the activity of intrarenal renin-angiotensin-aldosterone system, and reduce natriuretic peptide levels. SGLT2 inhibitors have been shown to be safe and beneficial for use in patients with a GFR ≥30mL/min/1.73m², associated with a constellation of signs of metabolic reprogramming, including enhanced ketogenesis, which may be responsible for the correction of metabolic reprogramming that underlies DKD. This article aims to provide a comprehensive overview and better understanding of the SGLT2 inhibitor and its benefits as it pertains to renal pathophysiology. It summarizes our recent understanding on the mechanisms of action of SGLT2 inhibitors, discusses the effects of SGLT2 inhibitors on diabetes and DKD, and presents future research directions and therapeutic potential.

Efficacy and Safety of SGLT-2 Inhibitors for Treatment of Diabetes Mellitus among Kidney Transplant Patients: A Systematic Review and Meta-Analysis

BACKGROUND

The objective of this systematic review was to evaluate the efficacy and safety profiles of sodium-glucose co-transporter 2 (SGLT-2) inhibitors for treatment of diabetes mellitus (DM) among kidney transplant patients.

METHODS

We conducted electronic searches in Medline, Embase, Scopus, and Cochrane databases from inception through April 2020 to identify studies that investigated the efficacy and safety of SGLT-2 inhibitors in kidney transplant patients with DM. Study results were pooled and analyzed utilizing random-effects model.

RESULTS

Eight studies with 132 patients (baseline estimated glomerular filtration rate (eGFR) of 64.5 ± 19.9 mL/min/1.73m2) treated with SGLT-2 inhibitors were included in our meta-analysis. SGLT-2 inhibitors demonstrated significantly lower hemoglobin A1c (HbA1c) (WMD = -0.56% [95%CI: -0.97, -0.16]; p = 0.007) and body weight (WMD = -2.16 kg [95%CI: -3.08, -1.24]; p < 0.001) at end of study compared to baseline level. There were no significant changes in eGFR, serum creatinine, urine protein creatinine ratio, and blood pressure. By subgroup analysis, empagliflozin demonstrated a significant reduction in body mass index (BMI) and body weight. Canagliflozin revealed a significant decrease in HbA1C and systolic blood pressure. In terms of safety profiles, fourteen patients had urinary tract infection. Only one had genital mycosis, one had acute kidney injury, and one had cellulitis. There were no reported cases of euglycemic ketoacidosis or acute rejection during the treatment.

CONCLUSION

Among kidney transplant patients with excellent kidney function, SGLT-2 inhibitors for treatment of DM are effective in lowering HbA1C, reducing body weight, and preserving kidney function without reporting of serious adverse events, including euglycemic ketoacidosis and acute rejection.