Nephrology Dialysis Transplant has published findings from an experimental kidney failure animal model showing vitamin K2, when combined with phosphate binders (PBs), could potentially be a useful therapy for chronic kidney disease (CKD) patients. NattoPharma, now part of Gnosis by Lesaffre, supported the study by providing MenaQ7 K2 as MK-7 as the source material and funding through a Norwegian Research Council grant.
The paper, "Combining phosphate binder therapy with vitamin K2 inhibits vascular calcification in an experimental animal model of kidney failure", presents evidence furthering the understanding of the role of vitamin K deficiency, specifically highlighting its potential as a cardiovascular therapy for an at-risk population, according to Prof Leon Schurgers, Professor of Biochemistry of Vascular Calcification and Vice-Chair of Biochemistry at the Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, and corresponding author to this paper.
"CKD patients often express intense vascular calcification as a symptom of their condition. People with chronic kidney failure are often prescribed phosphate binders to reduce the absorption of dietary phosphate, to lower their serum phosphate which is a major risk factor for vascular calcification. However, PBs also bind vitamin K, thereby potentially aggravating vitamin K deficiency,” Schurgers said. “This vitamin K binding by PBs may offset beneficial effects of phosphate level reduction on reducing vascular calcification. With this study, we wanted to assess whether combining PBs with K2 supplementation inhibited vascular calcification.”
In this experimental animal model of kidney failure, researchers induced K deficiency in rats, and then fed them a high phosphate diet in the presence of low or high vitamin K2. The animals were randomised to either control or one of four different phosphate binders for eight weeks. Vitamin K status was measured by plasma MK7 levels and immunohistochemically analysed in vasculature using ucMGP specific antibodies.
Results showed the combination of high vitamin K2 diet and PB treatment significantly reduced vascular calcification (VC) as measured by µ-CT compared to MK7 or PB treatment alone. Inactive MGP was significantly more present in the low vitamin K2 treated groups as compared to high K2 treated groups. Moreover, high vitamin K diet and PBs led to reduced vascular oxidative stress.
The authors concluded: "In an animal model of kidney failure with vitamin K-deficiency, neither phosphate binder therapy nor vitamin K2 supplementation alone prevented VC. However, the combination of high vitamin K2 with PB treatment significantly attenuated VC. Our findings might provide a combination therapy to combat VC in CKD. These findings should be translated to human research.”
“While this is early research, it is still significant in furthering our understanding of the K2 mechanism and its potential for improving cardiovascular health for the global population, but specifically at-risk populations like those suffering from CKD,” explains Dr. Hogne Vik, Chief Medical Officer with NattoPharma – Gnosis by Lesaffre, which supported this study through funding and supplying the K2 used in the study. “K2 is the only known compound to date shown to impact vascular calcification. We are proud to continue driving our understanding of Vitamin K2, building on the already substantial body of evidence showing it is a safe and effective cardiovascular protector.”
