RESUMO
AIMS: To estimate the effects of the sodium-glucose cotransporter 2 inhibitor (SGLT2i) on proteinuria and oxidative stress expression in type 2 diabetes patients. MATERIALS AND METHODS: 68 patients with type 2 diabetes mellitus (T2DM) were divided into three groups according urinary albumin-to-creatinine ratio (UACR), including T2DM with non-albuminuria group (UACR < 30 mg/g), T2DM with microalbuminuria group (30 ≤ UACR ≤ 300 mg/g), T2DM with macroalbuminuria group (UACR>300 mg/g). They all received SGLT2 inhibitors (SGLT2i) treatment for 12 weeks. The expression of advanced glycation end products (AGEs) in plasma and 8-hydroxy-2-deoxyguanosine (8-OHdG) in urine were measured as indications of oxidative stress. The 24-hour urine samples were collected to measure the concentration of proteinuria and 8-OHdG before and after 12 weeks SGLT2i treatment. Plasma renin activity (PRA), angiotensin II (Ang II) and Aldosterone (ALD) were measured to evaluate renin angiotensin aldosterone system (RASS) levels. RESULTS: After 12 weeks SGLT2 inhibitors treatment, the median values of 24-hour proteinuria decreased in macroalbuminuria compared to baseline (970 vs. 821 mg/d, P = 0.006). The median values of AGEs and 8-OHdG decreased in microalbuminuria and macroalbuminuria groups when compared to baseline, AGEs (777 vs. 136 ug/ml, P = 0.003) and (755 vs. 210 ug/ml, P = 0.001), 8-OHdG (8.00 vs. 1.88 ng/ml, P = 0.001) and (11.18 vs. 1.90 ng/ml, P < 0.001), respectively. Partial correlations showed that 8-OHdG were relevant to the baseline 24-h proteinuria (r = 0.389, p = 0.001), the reduction of OHdG (Δ8-OHdG) were positively correlated with the decrease of 24-h proteinuria (Δ24-h proteinuria) after 12 weeks of SGLT2i treatment (r = 0.283, P = 0.031). There was no significant correlation between 24-h proteinuria and AGEs in baseline (r = -0.059, p = 0.640) as well as between ΔAGEs and Δ24-h proteinuria (r = 0.022, p = 0.872) after12 weeks of SGLT2i treatment in T2DM patients. CONCLUSIONS: SGLT2i may reduce proteinuria in diabetic nephropathy patients, potentially by inhibiting renal oxidative stress, but not through the AGEs pathway and does not induce RAAS activation. TRIAL REGISTRATION: This clinical trial was registered on 15/10/2019, in ClinicalTrials.gov, and the registry number is NCT04127084.
RESUMO
To evaluate the effect of SGLT2 inhibitor (SGLT2i) on albuminuria, nephrin (NPH) and transforming-growth-factor-beta1 (TGF-ß1) levels in urine and low-grade inflammation in type 2 diabetes (T2D) patients. A randomized, blank-controlled clinical trial included 68 T2D patients and 10 controls. Based on the urinary albumin-to-creatinine ratio (UACR), 68 diabetic patients were stratified into three levels, UACR < 30 mg/g, UACR ⧠30 mg/g to ⦠300 mg/g and UACR Ë 300 mg/g, who were randomized (1:1:1) to receive SGLT2i treatment for 12 weeks. The concentrations of NPH and TGF-ß1 in urine were measured as indications of podocyte injury and renal fibrosis. Low-grade inflammation was assessed by the levels of IL-6, TNFα and hsCRP. After 12 weeks of SGLT2i treatment, the levels of UACR and NPH decreased, UTGF-ß1 increased in the T2D with microalbuminuria and macroalbuminuria groups, NPH (1.12 [0.59, 1.29] vs. 0.71 [0.41, 1.07] µg/ml, P = 0.022) and (1.29 [0.99, 1.96] vs. 0.93 [0.57, 1.31] µg/ml, P = 0.002), UTGF-ß1 (4.88 ± 1.31 vs. 7.27 ± 1.21 pg/ml, P < 0.001) and (4.30 ± 1.34 vs. 6.78 ± 2.59 pg/ml, P < 0.001), respectively. The changes in NPH were positively correlated with the UACR and negatively correlated with UTGF-ß1 in T2D with albuminuria. SGLT2i alleviate nephrin loss and enhance TGF-ß1 excretion in urine in T2DM with albuminuria. The anti-albuminuric effect of SGLT2i could be attributed to mitigating podocyte apoptosis and attenuating renal fibrosis.Trial registration This clinical trial was registered on 15/10/2019, in ClinicalTrials.gov, and the registry number is NCT04127084.
