來自肯塔基大學(xué)的研究者通過研究表明并齐，低維生素D的飲食可以引發(fā)個體出現(xiàn)腦部損傷侮穿，相關(guān)研究刊登于國際雜志Free Radical Biology and Medicine（FRBM）上。
除了具有保護骨骼健康的作用外蜕琴，新的研究證據(jù)揭示扰肌，維生素D對于其它器官和組織也非常重要，包括腦部等丢习。
文章中，研究者表示淮悼，對中年大鼠長達數(shù)月喂食低維生素D飲食會導(dǎo)致其腦部出現(xiàn)自由基損傷，而且也會使得大腦中許多不同的蛋白質(zhì)被損傷揽思。與此同時這些大鼠在學(xué)習和記憶能力上均出現(xiàn)了明顯的認知力降低的表現(xiàn)袜腥。
Allan Butterfield教授說道，維生素D缺失在老年個體中表現(xiàn)尤為明顯钉汗，我們的研究就揭示了低水平的維生素D為何會嚴重影響中老年個體大腦中的氧化狀態(tài)羹令；而血清中充足的維生素D對于阻斷大腦的自由基損傷以及更為惡劣的疾病則非常重要。
此前研究揭示低水平的維生素D和阿爾茲海默氏癥直接相關(guān)损痰，而且也和某些癌癥福侈、心臟疾病直接相關(guān)；如今人們的維生素D攝入水平依然很低卢未，研究者建議人們多食用一些富含維生素D的食物來補充維生素D肪凛，這樣對于保護個體的大腦健康非常有必要堰汉。
Dietary vitamin D deficiency in rats from middle to old age leads to elevated tyrosine nitration and proteomics changes in levels of key proteins in brain: Implications for low vitamin D-dependent age-related cognitive decline
Jeriel T.R. Keeneya, Sarah F?rstera, Rukhsana Sultanaa, Lawrence D. Brewerb, Caitlin S. Latimerb, Jian Caic, Jon B. Kleinc, Nada M. Porterb, D. Allan Butterfield
In addition to the well-known effects of vitamin D (VitD) in maintaining bone health, there is increasing appreciation that this vitamin may serve important roles in other organs and tissues, including the brain. Given that VitD deficiency is especially widespread among the elderly, it is important to understand how the range of serum VitD levels that mimic those found in humans (from low to high) affects the brain during aging from middle age to old age. To address this issue, 27 male F344 rats were split into three groups and fed isocaloric diets containing low (100 IU/kg food), control (1000 IU/kg food), or high (10,000 IU/kg food) VitD beginning at middle age (12 months) and continued for a period of 4–5months. We compared the effects of these dietary VitD manipulations on oxidative and nitrosative stress measures in posterior brain cortices. The low-VitD group showed global elevation of 3-nitrotyrosine compared to control and high-VitD-treated groups. Further investigation showed that this elevation may involve dysregulation of the nuclear factor κ-light-chain enhancer of activated B cells (NF-κB) pathway and NF-κB-mediated transcription of inducible nitric oxide synthase (iNOS) as indicated by translocation of NF-κB to the nucleus and elevation of iNOS levels. Proteomics techniques were used to provide insight into potential mechanisms underlying these effects. Several brain proteins were found at significantly elevated levels in the low-VitD group compared to the control and high-VitD groups. Three of these proteins, 6-phosphofructokinase, triose phosphate isomerase, and pyruvate kinase, are involved directly in glycolysis. Two others, peroxiredoxin-3 and DJ-1/PARK7, have peroxidase activity and are found in mitochondria. Peptidyl–prolyl cis–trans isomerase A (cyclophilin A) has been shown to have multiple roles, including protein folding, regulation of protein kinases and phosphatases, immunoregulation, cell signaling, and redox status. Together, these results suggest that dietary VitD deficiency contributes to significant nitrosative stress in brain and may promote cognitive decline in middle-aged and elderly adults.
