Effects of Ipragliflozin on Diabetic Nephropathy and Blood Pressure in Patients With Type 2 Diabetes: An Open-Label Study

Renal outcomes with sodium-glucose cotransporters 2 inhibitors

Diabetic nephropathy (DN) is one of the most serious complications of diabetes. Therefore, delaying and preventing the progression of DN becomes an important goal in the clinical treatment of type 2 diabetes mellitus. Recent studies confirm that sodium-glucose cotransporters 2 inhibitors (SGLT2is) have been regarded as effective glucose-lowering drugs with renal protective effect. In this review, we summarize in detail the present knowledge of the effects of SGLT2is on renal outcomes by analyzing the experimental data in preclinical study, the effects of SGLT2is on estimated glomerular flitration rates (eGFRs) and urinary albumin-creatinine ratios (UACRs) from clinical trials and observational studies, and renal events (such as renal death or renal failure requiring renal replacement therapy) in some large prospective cardiovaslucar outcomes trials. The underlying mechanisms for renoprotective activity of SGLT2is have been demondtrated in multiple diabetic and nondiabetic animal models including kidney-specific effects and secondary kidney effects related to amelioration in blood glucose and blood pressure. In conclusion, these promising results show that SGLT2is act beneficially in terms of the kidney for diabetic patients.

Effects of Dapagliflozin Compared with Sitagliptin and Metformin in Drug-Naïve Japanese Patients with Type 2 Diabetes: A 12-Week, Open-Label, Randomized, Active-Controlled Trial

INTRODUCTION

To compare the efficacy and tolerability of dapagliflozin with those of sitagliptin and metformin in patients with type 2 diabetes who have never received glucose-lowering agents.

METHODS

In this randomized, 12-week, open-label, active-controlled trial, 32 patients were randomly assigned to receive dapagliflozin 5 mg, sitagliptin 50 mg, or metformin 1000 mg per day for 12 weeks. At baseline and at week 12, the patients underwent a meal tolerance test (MTT).

RESULTS

After 12 weeks of treatment, the changes in fasting and postprandial plasma glucose and plasma glucose area under the curve (AUC)_0-120 min levels during the MTT from baseline were significantly improved in the three study groups, and there were no significant differences among the three study groups (P < 0.05). The mean changes in glycated hemoglobin (HbA1c) from baseline to week 12 were - 0.96%, - 1.24%, and - 1.40% in the dapagliflozin, sitagliptin, and metformin groups, respectively. Although there was no significant difference among the three study groups, the lowering effect of HbA1c tended to be greater in the metformin group than in the dapagliflozin group. In contrast, the insulin AUC_0-120 min levels at week 12 significantly decreased only in the dapagliflozin group (P = 0.049). Similarly, body weight was significantly reduced only in the dapagliflozin group (- 2.1 kg [- 2.7%], P = 0.047). Moreover, dapagliflozin significantly improved serum adiponectin levels (P = 0.003). However, there were no significant differences in the changes in these glycemic and metabolic parameters among the three study groups. No serious adverse events were documented in any group.

CONCLUSIONS

Dapagliflozin exerted beneficial effects similar to sitagliptin and metformin on glycemic parameters. In addition, dapagliflozin significantly reduced body weight and insulin AUC levels and improved serum adiponectin levels. Therefore, we suggest that these three hypoglycemic agents could be viable first-line medications for drug-naïve Japanese patients with type 2 diabetes.

TRIAL REGISTRATION

University Hospital Medical Information Network (UMIN000024427).

Effects of ipragliflozin on the development and progression of kidney disease in patients with type 2 diabetes: An analysis from a multicenter prospective intervention study

AIMS/INTRODUCTION

Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available.

METHODS

This was an investigator-initiated multicenter prospective intervention study in which ipragliflozin (50 mg) was administered once daily, and glycemic control, estimated glomerular filtration rate (eGFR) and adverse events were evaluated until 104 weeks after starting research.

RESULTS

There were 407 patients analyzed. In the eGFR ≥90 group and eGFR ≥60 to <90 group, eGFR had significantly decreased compared with baseline at all time points from 4 to 104 weeks. There were significant increases in the eGFR ≥45 to <60 groups compared with baseline at 36 weeks (2.3 ± 1.0) and 52 weeks (2.6 ± 1.2). Comparison between the eGFR <60, urine albumin-to-creatinine ratio >300 group and the eGFR <60, urine albumin-to-creatinine ratio <300 group showed a greater reduction in eGFR in the former (-5.4 ± 2.4 vs 3.3 ± 1.1) at 12 weeks and was maintained to 104 weeks. In any group, eGFR did not significantly decrease until 104 weeks compared with 4 weeks. The urine albumin-to-creatinine ratio after 52 weeks and after 104 weeks was significantly decreased compared with baseline in the eGFR ≥90 group.

CONCLUSIONS

Ipragliflozin lowers eGFR and corrects hyperfiltration in patients with high eGFR (eGFR ≥60). In patients with low eGFR (eGFR ≥30 to <60), ipragliflozin has the possibility of increasing eGFR and exerting a renoprotective effect.

Control of 24-hour blood pressure with SGLT2 inhibitors to prevent cardiovascular disease

The presence of hypertension (HTN) in patients with diabetes mellitus (DM) further worsens cardiovascular disease (CVD) prognosis. In addition, masked HTN and abnormal circadian blood pressure (BP) variability are common among patients with DM. Clinical trial data show that sodium-glucose cotransporter 2 inhibitors (SGLT2i) improve CVD prognosis and prevent progression of renal dysfunction in high-risk patients with type 2 DM (T2DM). Consistent reductions in 24-hour, daytime and nocturnal BP have been documented during treatment with SGLT2i in patients with DM and HTN, and these reductions are of a magnitude that is likely to be clinically significant. SGLT2i agents also appear to have beneficial effects on morning, evening and nocturnal home BP. Greater reductions in BP during treatment with SGLT2i have been reported in patient subgroups with higher body mass index, and in those with higher baseline BP. Other documented beneficial effects of SGLT2i include reductions in arterial stiffness and the potential to decrease the apnea-hypopnea index in patients with DM and obstructive sleep apnea. Recent guidelines highlight the important role of SGLT2i as part of the pharmacological management of patients with DM and HTN, and recommend consideration of SGLT2i early in the clinical course to reduce all-cause and CVD mortality in patients with T2DM and CVD. Overall, available data support a role for SGLT2i as effective BP-lowering agents in patients with T2DM and poorly controlled HTN, irrespective of baseline glucose control status. Sustained improvements in 24-hour BP and the 24-hour BP profile are likely to contribute to the CVD benefits of SGLT2i treatment.

Beneficial Effects of Ipragliflozin on the Renal Function and Serum Uric Acid Levels in Japanese Patients with Type 2 Diabetes: A Randomized, 12-week, Open-label, Active-controlled Trial

Objective To examine the add-on effects, compared to the existing antidiabetes treatment, of the sodium-glucose cotransporter 2 inhibitor ipragliflozin on glycemic control and the risk factors of cardiovascular disease (CVD) and chronic kidney disease (CKD) in patients with inadequately controlled type 2 diabetes. Methods This 12-week, randomized, open-label, active-controlled trial included 30 patients with type 2 diabetes who were randomized 1:1 to ipragliflozin and control groups (n=15 each). The ipragliflozin group received 50 mg of ipragliflozin once daily in addition to conventional therapy. The primary outcome was the change in hemoglobin A1c (HbA1c) from the baseline. Secondary outcomes were changes from the baseline in indices of glycemic control, uric acid (UA), renal function, and arterial stiffness. Results The patients' diminished estimated glomerular filtration rate (eGFR) was alleviated in the ipragliflozin group compared to the control group [difference between groups (Δ) =4.6 (95% confidence interval (CI): 1.5-7.7) mL/min/1.73 m², p=0.006] prior to significant improvements in HbA1c and other parameters, including anthropometric indices and arterial stiffness. Furthermore, ipragliflozin add-on therapy resulted in a greater reduction in serum UA levels than control therapy [Δ=-52.3 (95% CI: -85.5-19.1) μmol/L, p=0.003]. The changes in the eGFR with ipragliflozin treatment were associated with ipragliflozin-mediated changes in the UA, even after adjusting for the age, sex, baseline HbA1c, baseline UA, and baseline eGFR (standardized regression coefficient=-0.535, p=0.010). Conclusion Ipragliflozin add-on therapy was associated with beneficial renal effects in parallel with reducing serum UA levels.

Isomangiferin Attenuates Renal Injury in Diabetic Mice via Inhibiting Inflammation

AIM

Renal injury induced by diabetes is reported to be associated with inflammation. Isomangiferin (ISO), a xanthone C-glucoside from the Cyclopia subfamily, exhibits many pharmacological properties. This study aimed to evaluate the protection of ISO against renal damage in diabetic mice.

METHODS

Serum glucose, insulin, uric acid, creatinine, total cholesterol (TC), triglyceride (TG), and inflammatory cytokines in serum and the kidney of db/db diabetes model mice were detected. The components of high mobility group protein B1 (HMGB1)/NACHT leucine-rich repeat- and PYD-containing 3 (NLRP3)/nuclear factor kappa-B (NF-κB) pathway in the kidney were detected by Western blot and immunohistochemical analysis.

RESULTS

ISO improved lipid profile and glucose tolerance, and inhibited the production of inflammatory cytokines in a db/db model mice. Moreover, ISO decreased biochemical indexes in the serum and inhibited the activation of HMGB1/NLRP3/NF-κB signaling in the kidney of db/db model mice.

CONCLUSION

ISO provides protection against renal injury via inhibiting HMGB1/NLRP3/NF-κB signaling in a diabetic mouse model.

Long-Term Effects of Ipragliflozin on Diabetic Nephropathy and Blood Pressure in Patients With Type 2 Diabetes: 104-Week Follow-up of an Open-Label Study

Background

In our previous study, we investigated the efficacy of ipragliflozin, a sodium-glucose cotransporter (SGLT) 2 inhibitor on diabetic nephropathy in patients with type 2 diabetes and demonstrated that ipragliflozin significantly improved diabetic nephropathy in addition to reducing HbA1c and body weight. Herein, we conducted post-trial monitoring to determine whether these lowering effects on blood glucose and body weight or the beneficial effects on diabetic nephropathy were maintained long-term (104 weeks) after starting ipragliflozin treatment.

Methods

Initially, during a 24-week interventional trial period, a 50 mg dose of ipragliflozin was administered to 50 patients with type 2 diabetes without changing other treatments. During the post-trial monitoring period, these patients returned to hospital-based diabetes care according to their clinical needs. We continued monitoring their clinical data for 104 weeks in each hospital and analyzed the results on an intention-to-treat basis.

Results

The improvements in glycemic control and body weight reduction provided by 24-week ipragliflozin administration were maintained for 104 weeks. Despite a transient decrease during the intervention period, the estimated glomerular filtration rate (eGFR) was restored to near the baseline level at 104 weeks. Notably, in patients with diabetic nephropathy, the median urinary albumin-to-creatinine ratio (UACR) was significantly decreased from 119.2 (98.9 - 201.8) at baseline to 36.9 (19.7 - 204.7) mg/gCr at 104 weeks. In addition, eGFR was stable for 104 weeks, showing no decrease. In contrast, a significant positive correlation between UACR and blood pressure observed at 24 weeks disappeared after discontinuation of the intervention therapy.

Conclusions

The well-controlled HbA1c and body weight reductions were maintained for 104 weeks of post-trial follow-up. Moreover, ipragliflozin significantly reduced urinary albumin excretion in patients with diabetic nephropathy without decreasing eGFR.

The Effects of Sodium-Glucose Cotransporter 2 Inhibitors on Sympathetic Nervous Activity

The EMPA-REG OUTCOME study revealed that a sodium-glucose cotransporter 2 (SGLT2) inhibitor, empagliflozin, can remarkably reduce cardiovascular (CV) mortality and heart failure in patients with high-risk type 2 diabetes. Recently, the CANVAS program also showed that canagliflozin, another SGLT2 inhibitor, induces a lower risk of CV events. However, the precise mechanism by which an SGLT2 inhibitor elicits CV protective effects is still unclear. Possible sympathoinhibitory effects of SGLT2 inhibitor have been suggested, as significant blood pressure (BP) reduction, following treatment with an SGLT2 inhibitor, did not induce compensatory changes in heart rate (HR). We have begun to characterize the effects of SGLT2 inhibitor on BP and sympathetic nervous activity (SNA) in salt-treated obese and metabolic syndrome rats, who develop hypertension with an abnormal circadian rhythm of BP, a non-dipper type of hypertension, and do not exhibit a circadian rhythm of SNA. Treatment with SGLT2 inhibitors significantly decreased BP and normalized circadian rhythms of both BP and SNA, but did not change HR; this treatment was also associated with an increase in urinary sodium excretion. Taken together, these data suggest that an SGLT2 inhibitor decreases BP by normalizing the circadian rhythms of BP and SNA, which may be the source of its beneficial effects on CV outcome in high-risk patients with type 2 diabetes. In this review, we briefly summarize the effects of SGLT2 inhibitors on BP and HR, with a special emphasis on SNA.

Cinaciguat ameliorates glomerular damage by reducing ERK1/2 activity and TGF-ß expression in type-1 diabetic rats

Decreased soluble guanylate cyclase activity and cGMP levels in diabetic kidneys were shown to influence the progression of nephropathy. The regulatory effects of soluble guanylate cyclase activators on renal signaling pathways are still unknown, we therefore investigated the renal molecular effects of the soluble guanylate cyclase activator cinaciguat in type-1 diabetic (T1DM) rats. Male adult Sprague-Dawley rats were divided into 2 groups after induction of T1DM with 60 mg/kg streptozotocin: DM, untreated (DM, n = 8) and 2) DM + cinaciguat (10 mg/kg per os daily, DM-Cin, n = 8). Non-diabetic untreated and cinaciguat treated rats served as controls (Co (n = 10) and Co-Cin (n = 10), respectively). Rats were treated for eight weeks, when renal functional and molecular analyses were performed. Cinaciguat attenuated the diabetes induced proteinuria, glomerulosclerosis and renal collagen-IV expression accompanied by 50% reduction of TIMP-1 expression. Cinaciguat treatment restored the glomerular cGMP content and soluble guanylate cyclase expression, and ameliorated the glomerular apoptosis (TUNEL positive cell number) and podocyte injury. These effects were accompanied by significantly reduced TGF-ß overexpression and ERK1/2 phosphorylation in cinaciguat treated diabetic kidneys. We conclude that the soluble guanylate cyclase activator cinaciguat ameliorated diabetes induced glomerular damage, apoptosis, podocyte injury and TIMP-1 overexpression by suppressing TGF-ß and ERK1/2 signaling.

SGLT2 Inhibitors as a Therapeutic Option for Diabetic Nephropathy

Diabetic nephropathy (DN) is a major cause of end-stage renal disease (ESRD) worldwide. Glycemic and blood pressure (BP) control are important but not sufficient to attenuate the incidence and progression of DN. Sodium–glucose cotransporter (SGLT) 2 inhibitors are a new class of glucose-lowering agent suggested to exert renoprotective effects in glucose lowering-dependent and independent fashions. Experimental studies have shown that SGLT2 inhibitors attenuate DN in animal models of both type 1 diabetes (T1D) and type 2 diabetes (T2D), indicating a potential renoprotective effect beyond glucose reduction. Renoprotection by SGLT2 inhibitors has been demonstrated in T2D patients with a high cardiovascular risk in randomized controlled trials (RCTs). These favorable effects of SGLT2 inhibitors are explained by several potential mechanisms, including the attenuation of glomerular hyperfiltration, inflammation and oxidative stress. In this review article, we discuss the renoprotective effects of SGLT2 inhibitors by integrating experimental findings with the available clinical data.