Hypoglycemic action of vitamin K1 protects against early-onset diabetic nephropathy in streptozotocin-induced rats

Abstract Objectives Vitamin K is a potent regulator of vascular dynamics and prevents vascular calcification. Vitamin K is increasingly being recognized for its antioxidant and antiinflammatory properties. Recently we demonstrated that vitamin K1 (5 mg/kg) protects against streptozotocin-induced type 1 diabetes and diabetic cataract. The aim of this study was to determine whether the hypoglycemic action of vitamin K1 could inhibit early-onset diabetic nephropathy in a streptozotocin-induced rat kidney. Methods Male Wistar rats were administered with 35 mg/kg STZ and after 3 days were treated with vitamin K1 (5 mg/kg, twice a week) for 3 months. Blood glucose was monitored once a month. At the end of the study, animals were sacrificed and kidney was dissected out and analysed for free radicals, antioxidants, aldose reductase, membrane ATPases, histopathology evaluation and expression of pro- and anti-inflammatory cytokines. Urea, uric acid, creatinine, albumin and insulin levels were also estimated. Results Treatment of diabetic rats with vitamin K1 resulted in a decrease in blood glucose and prevented microalbuminuria. Vitamin K1 also reduced oxidative stress and protected renal physiology by modulating Ca 2+ and Na + /K + -ATPases. Vitamin K1 inhibited renal inflammation by reducing nuclear factor-κB and inducible nitric oxide synthase. Interleukin-10 levels were increased in renal tissues, suggesting the ability of vitamin K1 to trigger antiinflammatory state. The hypoglycemic action of vitamin K1 could have an indirect effect by inhibiting early-onset diabetic nephropathy triggered by high blood glucose. Conclusion Vitamin K1 could be an important nutrient based interventional strategy for early onset diabetic nephropathy.