Diabetes Mellitus (DM) is a chronic metabolic disease consisting of Type 1 or Type 2 diabetes. Although treatment of Type 1 diabetes primarily involves insulin therapy, inhibitors of sodium glucose co-transporters (SGLT’s) are a promising new therapeutic. Of particular interest are the two family members, SGLT1 and SGLT2 that collectively contribute to 100% of filtered glucose reabsorption within the kidneys. Consequently, sole SGLT2 inhibitors (SGLT2i) and dual SGLT1/2 inhibitors (SGLT1/2i) contribute to reducing blood glucose levels by reducing glucose reabsorption and promoting glucosuria and natriuresis. Research from our team on SGLT2i, showed that there is a compensatory mechanism whereby SGLT1 is upregulated. This therefore may warrant the combined use of SGLT1/2i. Our in vitro results demonstrated that whilst both the sole SGLT2i empagliflozin (EMPA) and dual SGLT1/2i sotagliflozin (SOTAG) significantly reduce glucose uptake within HK2 cells, the latter was more effective. In addition, our in vitro results indicate significantly more pronounced upregulation of SGLT1 protein with EMPA compared to SOTAG. Our in vivo mechanistic findings demonstrated that SGLT1/2i significantly increased renal SOD1 levels, whilst SGLT2i significantly elevated renal SOD2 levels. Therefore, our study highlighted that SGLT2i and SGLT1/2i differentially regulate protective anti-oxidant proteins in the kidney.

Background: Inhibition of sodium-glucose co-transporter 2 (SGLT-2) has been shown to be beneficial in the treatment of diabetic and non-diabetic patients with heart failure with reduced ejection fraction (HFrEF). The underlying mechanisms are incompletely understood. The present prospective study investigates for the first time the effect of empagliflozin on various soluble markers of inflammation in HFrEF. Methods: We included 50 inpatients with HFrEF and diabetes mellitus type 2. Half of the patients received a therapy with the SGLT-2-inhibitor empagliflozin in addition to standard medication, the other half of the patients did not receive empagliflozin and were considered as control group. Quality of life, functional status and soluble immunological parameters in serum were assessed at baseline and after 3 months. Results: Baseline characteristics of both groups revealed no significant differences. Patients on empagliflozin demonstrated a significant improvement in the Minnesota living with heart failure questionnaire (baseline 44.2 ± 20.2 vs. 24 ± 17.7; p<0.001), in distance in the 6-minute walk test (baseline 343 ± 145 m vs. 450 ± 115 m; p<0.001) and in soluble interleukin-6 level (baseline 21.7 ± 21.8 pg/ml vs. 13.7 ± 15.8 pg/ml; p=0.008). There was no significant change of these or other parameters in the control group (p>0.05 each). Conclusions: The empagliflozin-induced improvement of quality of life and functional capacity in patients with HFrEF and type 2 diabetes mellitus is accompanied by a substantial reduction of interleukin-6 levels. Thus, antiinflammatory effects may contribute to the benefits of SGLT2-inhibitors in heart failure.

Diabetes mellitus leads to cardiovascular complications including impaired cardiac β-adrenoceptor (β-AR) function. Sodium-glucose cotransporter-2 (SGLT2) inhibitors, such as empagliflozin (EMPA) improve outcomes in heart failure patients and animal models thereof. Therefore, we have investigated the effects of EMPA on in vivo cardiac function (pressure-volume loop analysis) and β-AR-mediated contractile responses (papillary strips) in streptozotocin (STZ; 40 mg/kg, i.p.)-induced diabes in male Sprague Dawley rats (control, EMPA-treated control, diabetic, EMPA-treated diabetic) in a design reflecting late-onset treatment. 13-16 weeks after STZ injection treatment with a low dose of EMPA (10 mg/kg/day, daily oral gavage) or vehicle was administered for another 8 weeks. EMPA did not change cardiac function in control rats. Diabetic rats had a reduced heart rate, cardiac output, stroke work, rate of contration and rate of relaxation and increased isovolumic relaxation, whereas in vitro responses were not markedly attenuated. Treatment with EMPA showed a trend for improvement of some but not all parameters. Our results indicate that low dose EMPA treatment had limited effects on cardiac impairment despite reducing blood glucose when initiated after diabetes is manifest. Future studies with a higher dose and greater sample sizes could help to clarify the possible benefits of EMPA on the diabetic heart.

SGLT2 inhibitors act to induce glucosuria and have been shown to be efficacious in the treatment of type II diabetes mellitus but have also been shown to positively affect cardiovascular conditions and some benefitting kidney function. SGLT2i have shown to be effective in more advanced conditions but may eventually be a treatment in more general metabolic dysfunction. Metabolic syndrome is a clinical diagnosis for establishing risk for ischemic heart disease and diabetes. The prevalence of type II diabetes mellitus, heart disease, and severe vascular events steadily increased over recent decades. In addition to the established benefits of diet and exercise, SGLT2 inhibitor therapy may be able to aid in the treatment of metabolic syndrome from its proven cardiovascular and anti-hyperglycemic benefits. Pharmacologic modeling in canines is also considered, as they present with similar diagnoses and offer a model that shares many of the characteristics of humans in metabolic dysfunction.

Objective: Aims to investigate the effects of empagliflozin (EMPA), a sodium-glucose co-transporter 2 (SGLT2) inhibitor, on renal fibrosis in male diabetic Sprague-Dawley (SD) rat model. Methods: Streptozotocin(STZ) were injected to establish diabetes model, EMPA (10 mg/kg·d) or normal saline (NS) were administered for four weeks. The changes in renal fibrosis-related biomarkers, include vimentin (VIM), collagen types I(Col-I), collagen types III(Col-III), fibroblast-specific protein 1(FSP-1), connective tissue growth factor (CTGF), fibronectin (FN) were evaluated. Renal pathology, serum glucose levels and urinary protein excretion were also assessed. Results: Biomarkers of renal fibrosis were significantly reduced in the EMPA group compared to those in the NS group after 4-week treatment, including VIM (519.84±83.37 vs. 663.27±91.84 ng/ml, P<0.05), Col-I (21.27±1.46 vs. 25.71±2.82 ng/ml , P<0.05) and Col-III (7.06±1.12 vs. 9.43±1.36 ng/ml, P<0.05), FSP-1 (4.38±0.81 vs. 5.70±0.78 ng/ml, P<0.05), and CTGF (1147±217 vs. 1556±235 pg/ml, P<0.05),respectively. Nevertheless, compared to normal control (NC) group, the levels of renal fibrosis-related biomarkers in the EMPA group showed no significant differences except for VIM, which was VIM (336.66±28.87 vs. 519.84±83.37 ng/mL, P<0.001). NS group rats showed notable renal tubular dilation and casts, EMPA group exhibited only mild tubular dilation. Conclusion: These findings suggest that empagliflozin reverse renal fibrosis potentially through inhibiting CTGF-mediated epithelial-mesenchymal transition.

Vascular calcification (VC) is associated with increased cardiovascular risks in patients with chronic kidney disease (CKD). Sodium-glucose cotransporter 2 inhibitors, like empagliflozin, can improve cardiovascular and renal outcomes. We assessed the expression of Runt-related transcription factor 2 (Runx2), interleukin (IL)-1β, IL-6, AMP-activated protein kinase (AMPK), nuclear factor erythroid-2-related factor (Nrf2), and heme oxygenase 1 (HO-1) in inorganic phosphate–induced VC in mouse VSMCs to investigate the mechanisms underlying empagliflozin’s therapeutic effects. We evaluated biochemical parameters, mean artery pressure (MAP), pulse wave velocity (PWV), transcutaneous glomerular filtration rate (GFR), and histology in an in vivo mouse model with VC induced by an oral high-phosphorus diet following a 5/6 nephrectomy in ApoE−/− mice. Compared to the control group, empagliflozin-treated mice showed significant reductions in blood glucose, MAP, PWV, and calcification, as well as increased calcium and GFR levels. Empagliflozin inhibited osteogenic trans-differentiation by decreasing inflammatory cytokine expression and increasing AMPK, Nrf2, and HO-1 levels. Empagliflozin mitigates high phosphate–induced calcification in mouse VSMCs through the Nrf2/HO-1 anti-inflammatory pathway by activating AMPK. Animal experiments suggested that empagliflozin reduces VC in CKD ApoE−/− mice on a high-phosphate diet.