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Vitamin K2 (VK2) belongs to the vitamin K family and comprises a number of subtypes differing in length of side chains consisting of isoprenoid groups (menaquinone-n, MK-n). It is essential for a number of physiological functions although the full spectrum of activity has not yet been elucidated. Due to its role in protection of mitochondrial damage, VK2 could be relevant in preventing disease progress in multiple sclerosis (MS).
We measured VK2 serum levels by the double antibody sandwich Enzyme-linked Immunosorbent Assay (ELISA) technique in MS patients and age and sex matched controls, both under vitamin D supplementation, and related it to disease characteristics and treatment.
Overall, 45 MS patients (31 females and 39 of the relapsing-remitting type) and 29 healthy controls (19 females) were included in the analysis. The MS patients had vastly lower VK2 blood levels than controls (235 ± 100 ng/ml vs. 812 ± 154 ng/ml, respectively). Female patients had significantly lower VK2 levels than males and a decrease with age by approximately 10% per decade was found. The VK2 levels were lower with increasing numbers of attacks per year and were higher in patients with optic nerve lesions. No consistent relationship with medications was detected.
The substantially lower levels of VK2 in MS patients could be due to depletion, lower production in the gut, diminished absorption or, less likely, reduced intake of precursor vitamin K1. The role of VK2 in MS development and progress deserves further study.