Long-Term Treatment with the Sodium Glucose Cotransporter 2 Inhibitor, Dapagliflozin, Ameliorates Glucose Homeostasis and Diabetic Nephropathy in db/db Mice

Abstract

Inhibition of sodium glucose cotransporter 2 (SGLT2) has been reported as a new therapeutic strategy for treating diabetes. However, the effect of SGLT2 inhibitors on the kidney is unknown. In addition, whether SGLT2 inhibitors have an anti-inflammatory or antioxidative stress effect is still unclear. In this study, to resolve these issues, we evaluated the effects of the SGLT2 inhibitor, dapagliflozin, using a mouse model of type 2 diabetes and cultured proximal tubular epithelial (mProx24) cells. Male db/db mice were administered 0.1 or 1.0 mg/kg of dapagliflozin for 12 weeks. Body weight, blood pressure, blood glucose, hemoglobin A1c, albuminuria and creatinine clearance were measured. Mesangial matrix accumulation and interstitial fibrosis in the kidney and pancreatic β-cell mass were evaluated by histological analysis. Furthermore, gene expression of inflammatory mediators, such as osteopontin, monocyte chemoattractant protein-1 and transforming growth factor-β, was evaluated by quantitative reverse transcriptase-PCR. In addition, oxidative stress was evaluated by dihydroethidium and NADPH oxidase 4 staining. Administration of 0.1 or 1.0 mg/kg of dapagliflozin ameliorated hyperglycemia, β-cell damage and albuminuria in db/db mice. Serum creatinine, creatinine clearance and blood pressure were not affected by administration of dapagliflozin, but glomerular mesangial expansion and interstitial fibrosis were suppressed in a dose-dependent manner. Dapagliflozin treatment markedly decreased macrophage infiltration and the gene expression of inflammation and oxidative stress in the kidney of db/db mice. Moreover, dapagliflozin suppressed the high-glucose-induced gene expression of inflammatory cytokines and oxidative stress in cultured mProx24 cells. These data suggest that dapagliflozin ameliorates diabetic nephropathy by improving hyperglycemia along with inhibiting inflammation and oxidative stress.

Functional expression of sodium-glucose transporters in cancer

“…S6 shows the time course of Me4FDG excretion into the urinary bladder with and without dapagliflozin (see also Movies S3 and S4). In general, dapagliflozin at this dosage inhibited Me4FDG uptake into pancreatic and prostate tumors by 40-50%, which compared well with the 50% reduction in the reabsorption of glucose from the glomerular filtrate (27). As in human tumors, Me4FDG uptake into in vitro slices of mouse tumors was blocked by dapagliflozin.…”

“…In the dapagliflozin trial, the mice were subjected to microCT the day before the beginning of treatment and then weekly until the end of the trial; the efficacy of the treatment in blocking SGLT was confirmed by microPET/CT with Me4FDG in a subset of the animals involved in the study. The PET/CT scans allowed us to measure the excretion of Me4FDG into the urinary bladder as a positive control of drug efficacy; in the control mice, no Me4FDG was excreted into the bladder, whereas about 50% of the filtered glucose load was excreted in mice treated with the SGLT2 inhibitor (27). After the end of the trials, the mice were killed and the tumors were harvested for morphologic analysis, fixed in 4% paraformaldehyde in PBS (pH 7.4), and then sliced into 7-μm-thick slices on Superfrost microscope slides (Fisher Scientific).…”

“…Subcutaneous ASPC-1 tumors produced in the upper thigh or lower flank of NSG mice were monitored for up to 4 wk during treatment with 30 mg/kg canagliflozin or dapagliflozin. The protocol for SGLT2 inhibitors was the one developed for inhibiting renal SGLT2 in mice and patients with diabetes (27)(28)(29)(30). As a positive control, we included treatment with the anticancer drug gemcitabine.…”

The effect of sodium glucose cotransporter 2 inhibition with empagliflozin on microalbuminuria and macroalbuminuria in patients with type 2 diabetes

“…In vitro and in vivo work has suggested that sodium glucose cotransport inhibition reduces markers of inflammation and fibrosis [18,19,[29][30][31]. Although we did not measure inflammatory markers in the present trials, future studies should assess the effect of SGLT2 inhibition on pro-inflammatory and pro-fibrotic mechanisms in diabetes and associated kidney disease.…”

The SGLT2 Inhibitor Empagliflozin Improves the Primary Diabetic Complications in ZDF Rats

“…This phenomenon is mostly explained by progression of β-cell apoptosis and dysfunction in the setting of diabetes, which is efficiently prevented by empagliflozin and other SGLT2i therapy [27,42,43]. SGLT2i therapy preserves β-cell integrity and functional capacity as shown by our immunohistological and -histochemical analysis.…”