VITAMINS The potential protective role of vitamin K in diabetic neuropathy DILIP MEHTA Viridis Biopharma 6/10 Jogani Industrial Complex ew cases of diabetes are symptomatic pain relief (3-5). V. N. Purav Marg, Chunabhatti increasing worldwide at a rapid Mumbai 400022, India The etiopathology of peripheral pace, with the total number of neuropathy is poorly understood and many [email protected] people with diabetes was projected factors, including dietary deficiencies, may www.viridisbiopharma.com Nto rise from 171 million in 2000 to 366 million contribute to the clinical manifestation of the in 2030 – an increase of nearly 200 million in condition. Deficiency of vitamin B12 (also only three decades. There are more cases of known as cobalamin), which results in a lack diabetes in women and urban populations, of a related compound, methylcobalamin, is with diabetes in developing countries projected manifested by megaloblastic anemia, and to double in the coming years (1). has been associated with significant Based on reports from the Centers for neurological pathology, especially peripheral Disease Control and Prevention, type 2 neuropathy (6-8). Vitamin B12 is also diabetes dult onset diabetes affects associated with the onset of diabetic approximately 9.3% of the general neuropathy. In patients with diabetic population in the United States in contrast to neuropathy, vitamin B12 deficiency may be 25.9% among those 65 years or older (2). aggravated by the use of antidiabetic agents Diabetes mellitus accounts for 90% of the such as metformin (9-11). Even short-term cases of diabetes patients (3,4). treatment with metformin causes a decrease The prevalence of type 2 diabetes in serum cobalamin, folic acid and an increases with age, higher then 25 body increase in homocysteine, which leads to mass index and the presence of the disease peripheral neuropathy in patients with in family history. The onset of symptoms is Dilip Mehta diabetes. Therefore, diabetic patients are gradual, often masked by chronic tiredness often advised to consume vitamin B12 and and stress of daily life (3,4). folic acid supplements as a prophylactic and have their blood levels monitored regularly. One of the most common and debilitating However, review of the epidemiological manifestations of diabetes is diabetic data to find the prevalence of vitamin B12 neuropathy or an inflammatory condition deficiency in early type 2 diabetic patients affecting the function and structure of the and the relationship with severity of peripheral nerves. This condition may peripheral neuropathy, found no evidence precede by years the formal diagnosis of that the use of oral vitamin B12 supplements diabetes. At least 50% of patients with is associated with improvement in the clinical diabetes have some form of neuropathy (5). symptoms of diabetic neuropathy. Currently, Early signs of peripheral neuropathy there is no effective treatment of diabetic manifest through what is colloquially neuropathy and persistence of the neurological described as “pins and needles” pain, symptoms, despite routine treatment, is a well paresthesia, loss of sensation in the feet and identified unmet medical need. loss of deep tendon reflexes at the ankles. The risk of developing peripheral neuropathy A recent clinical observation by two increases with the duration of diabetes and researchers, Dr. Dilip Mehta from Viridis Inc. deteriorating glycemic control. Some patients and Dr. Vaydia Ashok from Medical Research with neuropathy may experience extremely Center-Kasturba Health Society, Mumbai, is painful symptoms, whereas others may have that vitamin K2 relieves idiopathic muscle objectively marked neurological deficit cramps as well as symptoms of diabetic without significant painful neurological neuropathy; this illuminating observation led symptoms. Current clinical management to a pioneering human study evaluating the guidelines for diabetic peripheral neuropathy effects of vitamin K2 (menaquinone-7 or are limited to adequate glucose control and K2-7) in peripheral neuropathy caused by 20 MARCH/APRIL 2017 VITAMINS vitamin B12 deficiency and/or type 2 THE ROLE OF VITAMIN K myelin and repair of peripheral nerves diabetes. An open-labeled clinical study after demyelinating injury. Furthermore, was conducted in 30 patients clinically The etiology of diabetic neuropathy has research conducted in recent years linked presenting with peripheral neuropathy and been debated and one of the emerging alterations in sphingolipid metabolism to suffering from either megaloblastic anemia possibilities is neuropathy as an the aging process and neurodegenerative due to vitamin B12 deficiency and/or type 2 inflammatory autoimmune condition that disorders such as Alzheimer’s disease and diabetes. The Ethics Committee Approval for damages the myelin sheet of peripheral Parkinson’s disease. the study was obtained from the Ethics nerves and the potential role of vitamin K Committee of T.N.M.C.&B.Y.L. Nair Ch. in alleviating this condition. Chronic Hospital, and the trial was registered with inflammatory demyelinating REFERENCES Clinical Trial Registry of India (CTRI). polyneuropathy (CIDP) is a relapsing– Out of 30 patients enrolled for the remitting, immune system-mediated 1) Wild S., Roglic G., Green A., Sicree R., King study 23, 13 male and 10 female, patients disorder of the peripheral nervous system. H. “Global prevalence of diabetes: estimates were suffering from megaloblastic anemia There is an increasing body of literature for the year 2000 and projections for 2030” and 7, 3 male and 4 female, patients had Diabetes Care 2004, 27 (5), 1047-53. suggesting that the prevalence of CIDP 2) type 2 diabetes mellitus. The patients tends to be higher in diabetic patients, National Diabetes Statistics Report: Estimates were divided in two groups based upon of Diabetes and Its Burden in the United States especially in those of older age. 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Ed.; Springer, New York, 2010, in view of reported role of this vitamin in pp.357-70. mg/capsule, twice a day) was given orally myelin synthesis and myelin repair in 5) Russell J.W., Zilliox L.A. “Diabetic for 8 weeks. Patients kept a regular record central and peripheral nervous systems neuropathies” of the intensity of the symptoms during Continuum: Lifelong Learning (15). Myelin belongs to a group of in Neurology 2014, 20, 1226-40. the baseline and throughout the study. complex lipids called sphingolipids, 6) Head K.A. “Peripheral neuropathy: At the baseline group A had VAS score present in all mammalian cells where they pathogenic mechanisms and alternative of 8-9, and group B had VAS score of 6-8. are major components of cell membranes. therapies” Altern. Med. Rev. 2006, 11, 294-329. 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