Effect of SGLT2 inhibitor on renal function in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials

Renal, cardiovascular, and safety outcomes of adding sodium-glucose cotransporter-2 inhibitors to insulin therapy in patients with type-2 diabetes: a meta-analysis

AIMS

To investigate the renal, cardiovascular, and safety outcomes when sodium-glucose cotransporter-2 inhibitors (SGLT2is) were added to insulin therapy in patients with type-2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

We searched Embase, PubMed, and Cochrane libraries for reports published up to Feb 2023. Randomized controlled trials (RCTs) comparing SGLT2is and insulin combination therapy (SGLT2is + INS group) with insulin therapy alone (INS group) in T2DM were included.

RESULTS

Fourteen RCTs involving six thousand one hundred twenty subjects with durations of 12-104 weeks were included. Compared with the insulin group, the SGLT2is + INS group showed decreased glycosylated hemoglobin values and insulin dosages (P < 0.00001). Meanwhile, the SGLT2is + INS group had a reduced urinary albumin/creatinine ratio (UACR) by 25.42 mg/g and uric acid concentration (P = 0.030; P = 0.001, respectively) but the estimated glomerular filtration rate (eGFR) and renal-related adverse events were unaffected (P = 0.070; P = 0.880, respectively). Blood pressure and body weight were lower in the SGLT2is + INS group (P < 0.01). However, the risk of genital infection was bigger when SGLT2is were added to insulin therapy (P < 0.00001), but the risks of severe hypoglycemia or urinary tract infection were equal between the two groups (P > 0.05).

CONCLUSION

Adding SGLT2is to insulin therapy in T2DM patients showed better glucose control and decreased albuminuria, uric acid, blood pressure, and body weight without a reduction in the eGFR.

A systematic review of sodium-glucose cotransporter 2 inhibitors and renal profiles among Japanese patients with type 2 diabetes mellitus

BACKGROUND

We conducted a systematic review and meta-analysis to summarize the available literature and comprehensively appraise the renal profiles of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in Japanese patients with type 2 diabetes mellitus (T2DM).

METHODS

The electronic databases MEDLINE, Ichushi-web, and ClinicalTrials.gov were searched for studies without language restrictions from their inception until 20 July 2023 and CENTRAL until 21 September 2021. Studies were included if they were double-masked randomized controlled trials (RCTs) (1) including Japanese patients with T2DM aged > 18 years who received SGLT2i or a placebo, (2) reporting at least one renal outcome of serum creatinine or the estimated glomerular filtration rate (eGFR), and (3) with a follow-up of > 12 weeks. Cross-over and open label trials were excluded. The risk of bias based on the Cochrane risk-of-bias tool for randomized trials (RoB 2) was appraised. We computed the weighed mean difference with 95%CI for each renal outcome and used a random-effects model (inverse variance method).

RESULTS

We ultimately retrieved 13 RCTs including 2687 individuals in our review. The durations of RCTs ranged between 12 and 104 weeks. Only one trial had a longer duration of more than one year. Ten out of 13 RCTs reported serum creatinine, while nine included eGFR. Serum creatinine and eGFR were slightly worse with SGLT2i than with a placebo [mean difference 0.01 (95%CI 0.00 to 0.02) mg/dL, p = 0.002, mean difference - 1.30 (95%CI -2.23 to -0.37) mL/min/1.73 m2, p = 0.006, respectively]. Merged results revealed insignificant heterogeneity (I2 < 30%).

CONCLUSION

These results suggest that SGLT2i slightly worsens serum creatinine and eGFR in Japanese patients with T2DM. However, since the durations of most RCTs were short, the effects of eGFR in particular may be transient. Further evidence is needed from rigorous studies that focus on renal outcomes with a longer duration to confirm the present results.

Sodium-glucose cotransporter-2 inhibitors for type 2 diabetes mellitus in adults: An overview of 46 systematic reviews

AIMS

To summarize the evidence from systematic reviews (SRs) of randomized controlled trials (RCTs) evaluating the efficacy and safety of sodium-glucose cotransporter-2 (SGLT2) inhibitors versus placebo or active comparators for type 2 diabetes mellitus.

MATERIALS AND METHODS

We searched six databases between 2014 and 2021. We assessed the quality of evidence using Assessment of Multiple Systematic Reviews (AMSTAR 2) and Grading of Recommendations Assessment, Development and Evaluation (GRADE) and summarized the main outcome results according to their evidence of benefit (PROSPERO ID: CRD42019132431).

RESULTS

We included 46 SRs, comprising 175 RCTs and 136 096 participants. The results showed "clear evidence of benefit" in relation to: myocardial infarction (odds ratio [OR]/hazard ratio [HR] 0.85 to 0.91); cardiovascular mortality (OR/HR 0.67 to 0.86); heart failure (OR/HR 0.64 to 0.69); albuminuria progression and composite renal outcome (relative risk [RR]/HR 0.55 to 0.63); glycated haemoglobin (HbA1c) versus placebo (mean difference [MD] -0.49% to -0.77% [5.4 to 8.4 mmol/mol]); and weight versus placebo (MD -1.09 kg to -2.99 kg). "Possible benefit" was observed in relation to major adverse cardiovascular events (OR/HR 0.80 to 0.89), all-cause mortality and nonalcoholic fatty liver disease. SGLT2 inhibitors showed "clear evidence of no effect or equivalence" in relation to stroke and fractures. "Clear evidence of harm" was observed in relation to genital infections (RR/OR 2.06 to 5.25) and ketoacidosis (HR/OR 1.36 to 2.20). Regarding amputation risk and urinary tract infections, we found "no conclusions possible due to lack of evidence".

CONCLUSIONS

Our results showed that SGLT2 inhibitors have beneficial effects in relation to renal and cardiovascular outcomes (except for stroke), HbA1c and weight. Further studies are needed to assess urinary infections and amputation risk.

Efficacy and safety of Combination Therapy with Sodium-glucose Transporter 2 Inhibitors and Renin-Angiotensin System Blockers in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis

BACKGROUND

This study was designed to evaluate the efficiency and safety of combination therapy with SGLT2 inhibitors and RAS blockers, such as ACEI/ARB, in patients with T2DM.

METHODS

We searched PubMed, EMBASE, Web of Science and Cochrane Library from their inception to May 2020. Two authors independently performed study selection, risk of bias assessment and data extraction. The quality and risk of bias were assessed by the Cochrane Risk of Bias Tool. Statistical heterogeneity was qualified by the I-squared statistics.

RESULTS

Seven studies including 1757 patients were analyzed. Compared with ACEI/ARB alone, combination therapy with SGLT2 inhibitors and ACEI/ARB produced reduction in SBP (WMD -3.84 mmHg), DBP (WMD -1.06 mmHg), 24 h ambulatory SBP (WMD -4.59 mmHg), 24 h ambulatory DBP (WMD -2.08 mmHg), UACR(WMD -29.70%), eGFR (WMD -3.46 mL/min per 1·73 m2), HbA1c (SMD -0.48), FPG (SMD -0.28), uric acid (SMD -0.35), and body weight (SMD -0.29). The risk of hypoglycemia with combination therapy was higher than the control group (RR 1.37). As for the risk of total AEs, genital infection and urinary tract infection, no significant difference was revealed.

CONCLUSION

Compared with ACEI/ARB alone, the combination therapy with SGLT2 inhibitors and ACEI/ARB in T2DM was effective and well-tolerated, and could achieve additional effects, including better control of blood pressure, improvement of renal outcomes, alleviation of long-term renal function, and decrease of blood glucose and body weight. The combination therapy showed an increased risk of hypoglycemia.

The sodium-glucose cotransporter 2 inhibitor tofogliflozin prevents diabetic kidney disease progression in type 2 diabetic mice

Trials on cardiovascular and renal outcomes in patients with type 2 diabetes have consistently demonstrated that sodium–glucose cotransporter 2 (SGLT2) inhibitors reduce the risk of diabetic kidney disease (DKD) progression. However, their renal protective mechanisms have yet to be completely understood and the effect on albuminuria reduction in animal models is controversial. We investigated these issues using KK and KK‐A^y mice as a control (CTRL) and as a model for type 2 diabetes (DKD), respectively. KK‐A^y mice were treated with 0.015% tofogliflozin, which is an SGLT2 inhibitor, starting at seven weeks of age for eight weeks. Compared with the CTRL mice, the DKD mice had higher HbA1c levels and albuminuria. Although tofogliflozin treatment significantly lowered HbA1c levels, it did not reverse albuminuria. Tofogliflozin treatment enhanced damage in both the glomerular (i.e., enlarged mesangial area, increased foot process effacement rate, and decreased number of WT‐1‐positive cells) and tubulointerstitial (increased protein levels of KIM‐1 and MCP‐1, increased number of macrophages, and abnormal mitochondrial morphology) areas. Our results suggest that tofogliflozin may prevent glomerular and tubulointerstitial damage, partly by ameliorating hyperglycemia, renal inflammation, and abnormal mitochondrial morphology.

Antihypertensive and Renal Mechanisms of SGLT2 (Sodium-Glucose Linked Transporter 2) Inhibitors

Empaglifolzin, canagliflozin, and dapagliflozin are SGLT2 (sodium-glucose linked transporter type 2) inhibitors for treatment of type 2 diabetes mellitus that also reduce blood pressure, mortality, and cardiovascular disease and slow the loss of glomerular filtration rate. SGLT2 inhibitors inhibit the coupled reabsorption of sodium and glucose from the proximal tubules, thereby increasing renal glucose and sodium excretion, but they have more widespread renal effects, including inhibition of the sodium:proton exchanger. They increase the delivery of sodium to the loop of Henle and can thereby activate the tubuloglomerular feedback response to correct glomerular hyperfiltration. There are multiple potential mechanisms whereby these drugs lower blood pressure and preserve kidney function that are the focus of this review.

Possible involvement of normalized Pin1 expression level and AMPK activation in the molecular mechanisms underlying renal protective effects of SGLT2 inhibitors in mice

BACKGROUND

Recently, clinical studies have shown the protective effects of sodium glucose co-transporter2 (SGLT2) inhibitors against progression of diabetic nephropathy, but the underlying molecular mechanisms remain unclear.

METHODS

Diabetic mice were prepared by injecting nicotinamide and streptozotocin, followed by high-sucrose diet feeding (NA/STZ/Suc mice). The SGLT2 inhibitor canagliflozin was administered as a 0.03% (w/w) mixture in the diet for 4 weeks. Then, various parameters and effects of canagliflozin on diabetic nephropathy were investigated.

RESULTS

Canagliflozin administration to NA/STZ/Suc mice normalized hyperglycemia as well as elevated renal mRNA of collagen 1a1, 1a2, CTGF, TNFα and MCP-1. Microscopic observation revealed reduced fibrotic deposition in the kidneys of canagliflozin-treated NA/STZ/Suc mice. Interestingly, the protein level of Pin1, reportedly involved in the inflammation and fibrosis affecting several tissues, was markedly increased in the NA/STZ/Suc mouse kidney, but this was normalized with canagliflozin treatment. The cells showing increased Pin1 expression in the kidney were mainly mesangial cells, along with podocytes, based on immunohistochemical analysis. Furthermore, it was revealed that canagliflozin induced AMP-activated kinase (AMPK) activation concentration-dependently in CRL1927 mesangial as well as THP-1 macrophage cell lines. AMPK activation was speculated to suppress mesangial cell proliferation and exert anti-inflammatory effects in hematopoietic cells.

CONCLUSION

Therefore, we can reasonably suggest that normalized Pin1 expression and AMPK activation contribute to the molecular mechanisms underlying SGLT2 inhibitor-induced suppression of diabetic nephropathy, possibly at least in part by reducing inflammation and fibrotic change.