ABSTRACT
Objective:To evaluate the effect of canagliflozin on intrarenal fat content and oxygenation in newly-diagnosed type 2 diabetes patients.Methods:Twenty-three newly-diagnosed type 2 diabetes patients were divided into canagliflozin( n=11) and glimepiride control( n=12) groups .Both groups received MRI scanning with Dixon MRI and BOLD MRI sequence to assess patients′ intrarenal fat content, oxygenation level before treatment and 24 weeks after treatment. Fasting blood glucose, glycosylated hemoglobin, blood uric acid, blood lipids, blood pressure, weight, and other metabolic index were also tested before and after treatment. Furthermore, the relationship between body mass index(BMI) and intrarenal fat content and the correlation between changes in intrarenal fat content and improvement in renal hypoxia were analyzed. Results:No significant differences were found in baseline age, body weight, fasting blood glucose, glycosylated hemoglobin, blood lipid, and serum uric acid between the two groups. There was no significant difference in fasting blood glucose, glycosylated hemoglobin, cholesterol(CHO), low-density lipoprotein-cholesterol(LDL-C), and triglycerides(TG) levels in both groups after 12 and 24 weeks of treatment. The decrease in body weight, blood uric acid level, and diastolic blood pressure from baseline in the canagliflozin group was greater than those in the control group( P<0.05). Two groups of patients with type 2 diabetes at baseline had no obvious difference in intrarenal fat content, and the patients′ BMI showed no obvious correlation with degree of intrarenal fat accumulation. Canagliflozin treatment for 24 weeks could reduce intrarenal fat content, which was higher than that of control group. The R2 * values of renal cortex and medulla in the canagliflozin group decreased from baseline by 19.22% and 22.63% respectively( P<0.05), whereas no significant difference was seen in the glimepiride control group. The decrease of intrarenal fat content in the canagliflozin group was related to the improvement of renal cortex and medulla oxygenation. Conclusion:Canagliflozin can reduce intrarenal fat accumulation and improve renal cortical hypoxia in newly diagnosed type 2 diabetes patients with normal renal function.
ABSTRACT
VEGF-NO axis uncoupling is an important pathogenesis for DN. Reduced ß2GPI could play a part in VEGF signaling pathway and has a protective effect on diabetic vascular disease. This study investigates the effect of reduced ß2GPI on glomerular mesangial cells VEGF-NO axis uncoupling induced by high glucose. Compared to control group, glomerular mesangial cell line HBZY-1 cells treated with high glucose expressed higher levels of VEGF mRNA and protein and produced more ROS but less NO. The related proteins related to VEGF-NO axis were assayed. High glucose could significantly increase the expression of the level of VEGFR2 and obviously increase phosphorylation of Akt and eNOS but significantly decrease the expression of GTP cyclohydrolase 1 (GCH-1), reducing the production of eNOS dimer. Both ß2GPI and reduced ß2GPI partly reverse these effects caused by high glucose. Reduced ß2GPI had stronger effect than ß2GPI. GCH-1 is the speed limit of tetrahydrobiopterin (BH4) synthesis enzyme. As the key part of eNOS cofactors, BH4 could partly restore eNOS dimer induced by high glucose. Our results indicated that high glucose could interfere with eNOS dimer formation. ß2GPI and reduced ß2GPI can partly reverse the VEGF-NO axis uncoupling by restoring the GCH-1 expression level and then promote eNOS dimer formation.
Subject(s)
Glucose/physiology , Nitric Oxide Synthase Type III/metabolism , Vascular Endothelial Growth Factor A/physiology , Animals , Humans , Mesangial Cells , Rabbits , Rats , beta 2-Glycoprotein IABSTRACT
Rhesus retinal vascular endothelial cell line RF/6A cells were treated with human insulin. Cell proliferation, migration, and lumen formation, as well as the expressions of vascular endothelial growth factor-A ( VEGF-A ), VEGF-A receptors, and phosphorylated receptors were measured. Insulin promoted RF/6A cell proliferation, migration, and lumen formation ( all P＜0. 01 ). Insulin increased the expression of VEGF-A mRNA and improved its protein activity ( all P＜0. 05 ), and promoted the expression of VEGFR2 mRNA and its phosphorylation ( both P＜0. 01 ). There was no significant difference in the expression of VEGFR1 mRNA among the groups ( P＞0. 05 ).
