维生素D及其受体基因多态性与儿童疾病的相关性

人体内的维生素D源于肠道吸收及皮肤合成，属于脂溶性维生素，它不仅参与机体钙磷代谢的调节，还与内分泌、免疫、呼吸等多系统代谢调节相关。而维生素D受体及其基因多态性是维生素D在人体内发挥生物学效应的重要组成部分。本文就近些年来国内外关于血清维生素D水平、维生素D受体基因多态性与儿童呼吸、免疫等系统以及儿童生长发育、代谢等相关疾病的研究进行综述，为维生素D及其受体基因多态性在儿童疾病方面的研究及疾病的预防、治疗起到积极作用。     

VDR基因多态性与HBV宫内感染的相关性

人类感染乙型肝炎病毒后的临床结局复杂多样,包括自限性感染、无症状慢性携带状态和慢性乙型肝炎.病毒本身的毒力和环境因子不能完全解释这些差异,故考虑可能与人类遗传易感性有关,特别是与决定抗原递呈系统和病毒清除系统的基因有关.1,25-二羟维生素D3 作为一种免疫调节激素可以通过对其靶细胞的作用进而调节机体的免疫水平,影响疾病结局.1,25-二羟维生素D3对靶细胞的调节必须依赖于靶细胞上维生素D受体的基因型及表达水平,维生素D受体基因多态性造成了维生素D受体信使RNA在转录和表达水平上的差异,造成维生素D受体活性的不同,进而影响1,25-二羟维生素D3对免疫系统的调节作用.研究已证实维生素D受体基因多态性与多种肝脏疾病存在相关性,本文旨在对维生素D受体基因多态性与乙型肝炎病毒宫内传播的相关性研究作以综述,有关这些基因多态性的功能差异机制还需扩大样本进一步研究.     

维生素D受体基因多态性及维生素D水平与神经发育障碍关系的研究进展

维生素D及其受体在人体不同区域有广泛表达，后者介导活性维生素D的所有分子功能，其基因多态性已被证实与多种发育障碍类疾病易感性相关。现对维生素D受体基因多态性及维生素D水平与神经发育障碍关系的研究进行综述，以期为患儿临床早期预防、干预和治疗提供理论参考。     

维生素D受体及维生素D作用进展

维生素D受体(vitamin D receptor,VDR)基因上存在多个多态性位点,与许多疾病的发生发展密切相关.维生素D在骨代谢、免疫性疾病、肿瘤、糖尿病等疾病中作用被进一步发现,并在治疗许多疾病中得到应用.本文对维生素D受体及维生素D作用的进展进行综述.     

中国人群维生素D营养状况

20世纪30年代人工合成维生素D后,维生素D一直被认定为是微量营养素,参与钙磷代谢,促进骨骼发育。但是近年来对维生素D代谢有了深入的研究,维生素D需要在体内转化成具有活性的维生素D,即25-OHD3和1,25-(OH)2D3后,才能发挥生理作用。几乎在身体各种器官组织内都有维生素D受体,维生素D通过这些受体发挥作用,因而维生素D被认定是激素类物质。维生素D具有广泛的作用:如提高免疫、预防自身免疫性疾病、骨关节炎、Ⅰ型糖尿病和Ⅱ型糖尿病、心血管病、抗肿瘤,甚至与改善肺功能、哮喘、脑发育及精神疾病有关[1],而调节钙磷代谢仅仅是它的一种营养功能。我国开展以血清25-OHD3水平评价维生素D营养的资     

维生素D与妊娠期高血压疾病的相关性研究进展

妊娠期高血压疾病(hypertensive disorder complicating pregnancy,HDP)是孕妇在妊娠期所患的一种特有疾病,严重危害母婴的健康,同时也是导致我国孕产妇和围生儿死亡的最重要原因之一。维生素D、维生素D受体和HDP关系密切。流行病学资料表明,妊娠期高血压、子痫前期患者妊娠晚期血清1,25(OH)_2D_3水平下降,胎盘维生素D受体低表达、与维生素D抵抗有关。本文总结了维生素D、维生素D受体、维生素D抵抗及其与HDP相关性的研究进展。     

维生素D营养状况与儿童疾病

血清25-(OH)D 水平可以作为维生素D营养状况的客观指标,一般认为血清25-(OH)D≥75 nmol/L是维生素D较为理想的水平。儿童是维生素 D缺乏的潜在高危人群,维生素 D缺乏不仅可使儿童患佝偻病,而且还与心脑血管疾病、呼吸系统疾病、自身免疫性疾病、肾脏疾病、神经精神疾病、肿瘤、糖尿病等密切相关。本文就此方面的研究进展进行系统综述。     

维生素A、D、E与妊娠期高血压疾病患者的相关性及其对预后的评估价值

目的探究维生素A、D、E与妊娠期高血压疾病患者病情严重程度及预后相关性及其对预后的评估价值。方法选取2017年5月-2019年5月该院收治的149例妊娠期高血压疾病孕妇为研究组,同期在该院进行健康体检的50例孕妇为对照组,检测并比较研究组与对照组血清维生素A、D、E水平,比较病情严重程度不同的妊娠期高血压疾病孕妇血清维生素A、D、E水平,比较围生儿预后情况不同的妊娠期高血压疾病孕妇血清维生素A、D、E水平,分析维生素A、D、E检测对妊娠期高血压疾病孕妇预后的预测价值。结果研究组血清维生素A、D、E水平显著低于对照组(P0. 05);中度妊娠期高血压疾病孕妇血清维生素A、D、E水平显著低于轻度妊娠期高血压疾病孕妇(P0. 05);重度妊娠期高血压疾病孕妇血清维生素A、D、E水平显著低于中度妊娠期高血压疾病孕妇(P0. 05);围生儿预后不良的妊娠期高血压疾病孕妇血清维生素A、D、E水平显著低于围生儿预后良好的妊娠期高血压疾病孕妇(P0. 05);维生素A、D、E联合检测对妊娠期高血压疾病孕妇预后的预测价值明显优于各项指标单独检测(P0. 05),维生素A、D、E预测界值分别为35. 3 ng/ml、40. 5 ng/ml、45. 6 ng/ml。结论维生素A、D、E在妊娠期高血压疾病患者血清中呈低水平状态,且与患者病情严重程度及预后相关,维生素A、D、E联合检测对评估妊娠期高血压疾病孕妇预后有较高准确度,可能成为妊娠期高血压疾病预后的预测指标。     

维生素D缺乏与儿童疾病表观遗传学研究

维生素D不仅对骨代谢有着经典的作用,同时在免疫、细胞增殖和分化中有重要的作用。最近的研究发现,孕期维生素D水平也可能通过表观遗传修饰影响到后代儿童期非骨骼系统疾病的易感性,如哮喘,自身免疫性疾病和神经精神疾病等。本文将综述维生素D缺乏与儿童疾病表观遗传学的研究进展。     

铜陵市婴儿维生素D制剂服用情况调查分析

正维生素D是维持机体正常功能所必须一类脂溶性维生素,维生素D的缺乏在全世界范围内非常普遍,已成为公共卫生问题[1],维生素D缺乏不仅可使小儿患佝偻病,而且还与心血管疾病、呼吸系统疾病、自身免疫性疾病、肾脏、精神疾病等密切相关[2]。合理补充维生素D,对维持体内维生素D水平有重要意义。由于维生素D的应用在不同人群都存在不合理情况,为了解铜陵市婴儿维生素D服用情况,促进维生素D的合理服用,本文对铜陵市     

维生素D缺乏与女性生殖关系的研究进展

维生素D在体内不止作为维生素，也可以作为激素发挥作用。它是一种可以调节钙磷代谢的固醇类衍生物，在心血管疾病、免疫调节、抗炎、癌症、生殖等各方面都能发挥一定的生物学作用。该生物学作用通常通过可溶性蛋白维生素D受体（VDR）来实现。VDR是一种位于靶细胞核内的转录因子，分布在人类各种系统组织中，包括女性生殖系统。近年有关维生素D与女性生殖系统的关系引起人们关注。维生素D一定程度上影响卵巢生理功能及女性生育力，同时与一些女性生殖系统疾病有关，如多囊卵巢综合征、子痫前期、子宫内膜异位症、妊娠期糖尿病等。现就维生素D缺乏与女性生殖系统关系的相关研究进行综述。     

Vitamin D, invariant natural killer T-cells and experimental autoimmune disease

Vitamin D is an important regulator of the immune system in general and multiple sclerosis in particular. Experimentally (i), invariant natural killer T (iNKT) cells have been shown to be important suppressors of autoimmune diseases such as experimental autoimmune encephalomyelitis (EAE; an animal model of multiple sclerosis). Conversely, in experimental allergic asthma iNKT cells are required for disease induction and are therefore pathogenic. The active form of vitamin D (calcitriol) suppresses EAE. The development of EAE symptoms is accelerated in vitamin D deficiency. Interestingly experimental asthma is less severe in vitamin D deficiency although there is no effect of calcitriol on disease severity. The data suggest that an important target of vitamin D in EAE and asthma are the iNKT cells. Vitamin D and/or vitamin D receptor deficiency results in the impaired development of iNKT cells. Vitamin D is critical very early during development of the immune system. Low levels of vitamin D in utero resulted in significantly reduced numbers of iNKT cells that failed to recover when calcitriol was used to supplement neonatal or adult mice. The data suggest that one of the consequences of early vitamin D deficiency is a reduction in the numbers of iNKT cells that develop. The iNKT cells are required for the beneficial effects of calcitriol in EAE. The important role of vitamin D on iNKT cells could impact the development of human immune-mediated diseases including multiple sclerosis and asthma.     

Vitamin d and its role in cancer and immunity: a prescription for sunlight.

Vitamin D has been recognized for more than a century as essential for the normal development and mineralization of a healthy skeleton. More extensive roles for vitamin D were suggested by the discovery of the vitamin D receptor (VDR) in tissues that are not involved in calcium and phosphate metabolism. VDR has been discovered in most tissues and cells in the body and is able to elicit a wide variety of biologic responses. These observations have been the impetus for a reevaluation of the physiologic and pharmacologic actions of vitamin D. Here, we review the role of vitamin D in regulation of the immune system and its possible role in the prevention and treatment of cancer and immune-mediated diseases.     

Vitamin D and respiratory infection in adults

Vitamin D insufficiency is a global issue that has significant implications for health. The classical role of vitamin D in bone mineralisation is well known; vitamin D deficiency leads to rickets, osteomalacia or osteoporosis. The role of vitamin D in an immune system is less known. Vitamin D is not an actual vitamin but a secosteroid hormone produced in the skin from 7-dehydrocholesterol after exposure to sunlight UVB radiation. Nutrition and supplements are main sources of vitamin D in wintertime in northern countries as sunlight exposure is inadequate for the production. For activation vitamin D needs to be hydroxylated in liver to form 25-hydroxyvitamin D and in kidney to 1,25-dihydroxyvitamin D, the most active hormone in Ca absorption in the gut. For determination of vitamin D status serum 25-hydroxyvitamin D level, the major circulating form of the hormone is to be measured. Vitamin D regulates gene expression through binding with vitamin D receptors, which dimerises with retinoid X receptor. This complex binds to vitamin D-responsive elements inside the promoter regions of vitamin D-responsive genes. Vitamin D has a key role in innate immunity activation; the production of antimicrobial peptides (cathelicidin and defensins) following Toll-like receptor stimulation by pathogen lipopeptides is dependent on sufficient level of 25-hydroxyvitamin D. Clinically, there is evidence of the association of vitamin D insufficiency and respiratory tract infections. There is also some evidence of the prevention of infections by vitamin D supplementation. Randomised controlled trials are warranted to explore this preventive effect.     

Understanding the role of vitamin A and its precursors in the immune system

Vitamin A is the first defined vitamin and is also known as an anti-inflammatory micronutrient. Although the primary biological function is preservation of epithelial tissue integrity, vision and growth, vitamin A also plays a role in immune system regulation. It is known that susceptibility to infections increases in developing countries due to vitamin A deficiency. Therefore, the purpose of this review is to evaluate the role of vitamin A on the immune system in line with current studies. In this review, we focused on the immunobiological effects of vitamin A and its precursors. Vitamin A refers to retinoids and carotenoids, but both function in the body through the most active form, all trans retinoic acid. All trans retinoic acid has the highest affinity of nuclear retinoic acid receptor. Reports from in-vivo and in-vitro studies shown that the formation of retinoic acid/retinoic acid receptor complex is important in the generation of innate and adaptive immune cell response. In addition to immune cell response, vitamin A also plays an important role in mucus secretion, morphological formation and functional maturation of epithelial cells. In this way, vitamin A appears to contribute to immune development by regulating immune cell response and providing mechanistic defense. Vitamin A has received particular attention in recent years as the vitamin have been shown to have a crucial effect on the immune response. Although more randomized controlled studies are needed, data from observational human studies have shown that vitamin A is associated with infectious, inflammatory, allergic diseases and cancers.     

The Relationship Between Female Reproductive Functions and Vitamin D

Nonclassical target organs recently defined for vitamin D, a major regulator of calcium phosphorus homeostasis and bone health, include reproductive ones. This compilation study focuses on the potential effects of vitamin D on female reproductive functions. Vitamin D receptor enzymes that metabolize vitamin D are expressed in both central and peripheral reproductive organs. Most studies suggest that vitamin D may be directly or indirectly related to gonadal functions. Vitamin D's effects on reproductive functions may be indirectly related to diseases such as polycystic ovary syndrome (PCOS), uterine leiomyomas, and endometriosis. In case of vitamin D deficiency during infertility treatment, vitamin D supplementation can be recommended especially for women who have PCOS, insulin resistance, or low anti-Mullerian hormone levels. Supplementation, however, should take into account possible toxic effects of high-dose vitamin D. To be able to recommend measuring vitamin D as a routine screening test and to better understand the effects of vitamin D and its supplementation on female reproductive functions, larger randomized controlled prospective studies are needed.     

Vitamin D and the Athlete: Risks,Recommendations, and Benefits

Vitamin D is well known for its role in calcium regulation and bone health, but emerging literature tells of vitamin D’s central role in other vital body processes, such as: signaling gene response, protein synthesis, hormone synthesis, immune response, plus, cell turnover and regeneration. The discovery of the vitamin D receptor within the muscle suggested a significant role for vitamin D in muscle tissue function. This discovery led researchers to question the impact that vitamin D deficiency could have on athletic performance and injury. With over 77% of the general population considered vitamin D insufficient, it’s likely that many athletes fall into the same category. Research has suggested vitamin D to have a significant effect on muscle weakness, pain, balance, and fractures in the aging population; still, the athletic population is yet to be fully examined. There are few studies to date that have examined the relationship between vitamin D status and performance, therefore, this review will focus on the bodily roles of vitamin D, recommended 25(OH)D levels, vitamin D intake guidelines and risk factors for vitamin D insufficiency in athletes. In addition, the preliminary findings regarding vitamin D’s impact on athletic performance will be examined.     

Immune Modulation by Vitamin D and Its Relevance to Food Allergy

Apart from its classical function in bone and calcium metabolism, vitamin D is also involved in immune regulation and has been linked to various cancers, immune disorders and allergic diseases. Within the innate and adaptive immune systems, the vitamin D receptor and enzymes in monocytes, dendritic cells, epithelial cells, T lymphocytes and B lymphocytes mediate the immune modulatory actions of vitamin D. Vitamin D insufficiency/deficiency early in life has been identified as one of the risk factors for food allergy. Several studies have observed an association between increasing latitude and food allergy prevalence, plausibly linked to lower ultraviolet radiation (UVR) exposure and vitamin D synthesis in the skin. Along with mounting epidemiological evidence of a link between vitamin D status and food allergy, mice and human studies have shed light on the modulatory properties of vitamin D on the innate and adaptive immune systems. This review will summarize the literature on the metabolism and immune modulatory properties of vitamin D, with particular reference to food allergy.     

Current perspectives on vitamin D, immune system, and chronic diseases

Accumulating data support that vitamin D possesses several biological and molecular actions apart from its role in calcium homeostasis. Immune cells express vitamin D receptor and are capable of metabolizing vitamin D. Within this context, experimental studies show that vitamin D modulates immune and inflammatory responses. Epidemiologic evidence linking poor vitamin D status to autoimmune diseases, type 2 diabetes, and cardiovascular disease suggests that insufficient vitamin D may be involved in the etiology of such disorders. Given the impact of immune and inflammatory abnormalities in the development of chronic diseases, including autoimmune disorders, it is possible that vitamin D might reduce chronic disease risk by modulating the immune system.