Division of Human Anatomy, Department of Biomedical Sciences and Biotechnologies, University of Brescia, Brescia, Italy.
Histol Histopathol. 2012 Aug;27(8):1055-66. doi: 10.14670/HH-27.1055.
Silicon is not generally considered an essential nutrient for mammals and, to date, whether it has a biological role or beneficial effects in humans is not known. The results of a number of studies suggest that dietary silicon supplementation might have a protective effect both for limiting aluminium absorption across the gut and for the removal of systemic aluminium via the urine, hence, preventing potential accumulation of aluminium in the brain. Since our previous studies demonstrated that aluminium exposure reduces the number of nitrergic neurons, the aim of the present study was to compare the distribution and the morphology of NO-containing neurons in brain cortex of mice exposed to aluminium sulphate dissolved in silicic acid-rich or poor drinking water to assess the potential protective role of silicon against aluminium toxicity in the brain. NADPH-d histochemistry and nNOS immunohistochemistry showed that high concentrations of silicon in drinking water were able to minimize the impairment of the function of nitrergic neurons induced by aluminium administration. We found that silicon protected against aluminium-induced damage to the nitrergic system: in particular, we demonstrated that silicon maintains the number of nitrergic neurons and their expression of nitrergic enzymes at physiological levels, even after a 12 and 15 month exposure to aluminium.
硅通常不被认为是哺乳动物的必需营养素，迄今为止，尚不清楚它在人类中是否具有生物学作用或有益影响。许多研究的结果表明，饮食中补充硅可能具有保护作用，可以限制肠道对铝的吸收，并通过尿液去除系统中的铝，从而防止铝在大脑中的潜在积累。由于我们之前的研究表明铝暴露会减少氮能神经元的数量，因此本研究的目的是比较暴露于溶解在富含硅酸或贫硅饮水中的硫酸铝的小鼠大脑皮层中含氮神经元的分布和形态，以评估硅对大脑中铝毒性的潜在保护作用。NADPH-d 组织化学和 nNOS 免疫组织化学显示，饮用水中高浓度的硅能够最大限度地减少铝给药引起的氮能神经元功能障碍。我们发现硅可以防止铝对氮能系统造成损害：特别是，我们证明硅即使在 12 个月和 15 个月暴露于铝后，也能维持氮能神经元的数量及其氮能酶的表达处于生理水平。
