Clinical implications of a possible role of vitamin D in multiple sclerosis

Hypovitaminosis D is currently one of the most studied environmental risk factors for multiple sclerosis (MS) and is potentially the most promising in terms of new clinical implications. These practical consequences, which could be applied to MS patients without further delay, constitute the main purpose of this review. Vitamin D is involved in a number of important general actions, which were not even suspected until quite recently. In particular, this vitamin could play an immunomodulatory role in the central nervous system. Many and varied arguments support a significant role for vitamin D in MS. In animal studies, vitamin D prevents and improves experimental autoimmune encephalomyelitis. Epidemiologically, latitude, past exposure to sun and the serum level of vitamin D influence the risk of MS, with, furthermore, significant links existing between these different factors. Clinically, most MS patients have low serum levels of vitamin D and are in a state of insufficiency or even deficiency compared to the international norm, which has been established on a metabolic basis. Large therapeutic trials using vitamin D are still lacking but the first results of phase I/II studies are promising. In the meantime, while awaiting the results of future therapeutic trials, it can no longer be ignored that many MS patients have a lack of vitamin D, which could be detected by a serum titration and corrected using an appropriate vitamin D supplementation in order to restore their serum level to within the normal range. From a purely medical point of view, vitamin D supplementation appears in this light to be unavoidable in order to improve the general state of these patients. Furthermore, it cannot currently be ruled out that this supplementation could also be neurologically beneficial

Prevalence of Vitamin D insufficiency and low bone mineral density in elderly Thai nursing home residents

<p>Abstract</p> <p>Background</p> <p>Numerous emerging data from research on osteoporosis among Asians found differences from Caucasians. Therefore, the aim of this study was to determine the prevalence of vitamin D insufficiency and osteoporosis in elderly participants from two nursing homes in Thailand, a country located near the equator.</p> <p>Methods</p> <p>The subjects of this cross-sectional study comprised 93 elderly Thai women who were living in institutional long-term nursing homes for the aged. Demographic data, daily food and calcium intake, physical activity, and sunlight exposure were measured. Lumbar spine and femoral neck bone mineral density (BMD) and biochemical levels including serum 25 hydroxyvitamin D [25(OH)D] and bone turnover markers were assessed. Vitamin D insufficiency was defined as 25(OH)D level < 70 nmol/l.</p> <p>Results</p> <p>The mean age of subjects was 75.2 ± 6.0 (SD) years. Dietary calcium intake was low (322 ± 158 mg/day) The mean 25(OH)D level was 64.3 ± 14.9 nmol/L and the prevalence of vitamin D insufficiency was 38.7% (95% CI: 28.8%, 49.4%). There was no correlation between serum 25(OH)D concentrations and age (r = −.11, p = 0.3). The mean BMD of lumbar spine and femoral neck were 0.92 ± 0.19 and 0.65 ± 0.10 g/cm², respectively. Nearly a half of the subjects had osteopenia (44.1%, 95% CI: 33.8%, 54.8%) and osteoporosis (47.3%, 95% CI: 36.9%, 57.9%). Circulating C-terminal telopeptide of type I collagen (CTx) level correlated significantly with both lumbar spine (r = −0.26, p = 0.01) and femoral neck BMD (r = −0.25, p = 0.02).</p> <p>Conclusions</p> <p>More than one-third of Thai elderly women residing in nursing homes had vitamin D insufficiency. Almost all nursing home residents had osteoporosis and/or osteopenia.</p

Global vitamin D status and determinants of hypovitaminosis D

The aim of the study was to compare the structural and functional parameters of the myocardium in different genotypes of polymorphic markers BsmI (B/b) (rs1544410) and FokI (F/f) (rs2228570) of the vitamin D receptor gene (VDR) in individuals with cardiovascular diseases (CVD). Materials and Methods. We examined 198 patients with CVD. BsmI and FokI of the VDR gene were determined by the polymerase chain reaction. The blood levels of parathyroid hormone, 25(OH)D total, endothelin-1, plasma renin activity were revealed by the method of enzyme immunoassay. The calcium and phosphorus level in the blood was defined by the colorimetric method. Echocardiography was performed by GE Logic P5 Premium (Korea) with a phased sector sensor with a frequency of 2–4 MHz in the modes M-, B-, PW, CW. Results. All participants were divided into groups according to genotypes of FokI and BsmI of the VDR gene. For each polymorphism, the groups were comparable in age, CVD, blood pressure, heart rate, body mass index and levels of the estimated biomarkers. Significant differences (p &lt; 0.05) in the sizes of the aorta and the left atrium (LA), in the sizes and volumes of the left ventricle (LV) and its walls, the diameter of the LV outlet tract and the ejection fraction between the groups with the genotypes of FF and ff were established. In addition, differences (p &lt; 0.05) were found in the aorta size, LA and interventricular septum between the groups with the genotypes of ff and Ff. According to the genotypes of BsmI of the VDR gene, the groups did not differ significantly in the estimated structural and functional parameters of the myocardium and aorta. Hypertrophy of the LV is diagnosed in 78.6 % of participants. Conclusions. Polymorphism of FokI, but not of BsmI of the VDR gene is associated with structural and functional parameters of the myocardium and aorta in individuals with CVD in the Grodno region of Belarus. With the greatest frequency, LV hypertrophy occurs with Ff (37.9 %) and Bb (33.8 %).Цель исследования – сравнение структурно-функциональных показателей миокарда при разных генотипах полиморфных маркеров BsmI (B/b) (rs1544410) и FokI (F/f) (rs2228570) гена рецептора витамина D (VDR) у лиц с сердечно-сосудистыми заболеваниями (ССЗ). Материалы и методы. Обследовано 198 пациентов с ССЗ. Определение BsmI и FokI гена VDR проводили методом полимеразной цепной реакции. Содержание в крови паратиреоидного гормона, 25(OH)D общего, эндотелина-1, активность ренина плазмы определяли методом иммунофер- ментного анализа. Определение в крови уровня кальция и фосфора проводилось колориметрическим методом. Эхо- кардиография выполнялась аппаратом GE Logic P5 Premium (Корея) фазированным секторным датчиком с частотой 2–4 мГц в режимах М-, В-, PW, CW. Результаты. Все обследованные были разделены на группы по генотипам FokI и BsmI гена VDR. При каждом полиморфизме группы были сопоставимы по возрасту, ССЗ, значениям артериального давления, частоте сердечных сокращений, индексу массы тела и уровням оцененных биомаркеров. Установлены достоверные (p &lt; 0,05) отличия по размерам отделов аорты, левого предсердия (ЛП), размерам и объемам левого желудочка (ЛЖ) и его стенок, диаметром выходного тракта ЛЖ и фракцией выброса между группами с генотипом FF и ff. Кроме того, установлены отличия (p &lt; 0,05) по размерам отделов аорты, ЛП и толщиной межжелудочковой перегородки между группами с генотипом ff и Ff. По генотипам BsmI гена VDR группы достоверно не отличались по оцененным структурно-функциональным показателям миокарда и аорты. Гипертрофия ЛЖ диагностирована у 78,6 % обследованных. Заключение. Полиморфизм FokI, но не BsmI гена VDR ассоциирован со структурно-функциональными показателями миокарда и аорты у лиц с ССЗ у жителей Гродненского региона Беларуси. С наибольшей частотой гипертрофия ЛЖ встречается при Ff (37,9 %) и Bb (33,8 %) генотипах.