Ramos Patrícia, Santos Agostinho, Pinto Edgar, Pinto Nair Rosas, Mendes Ricardo, Magalhães Teresa, Almeida Agostinho
LAQV/REQUIMTE, Department of Chemical Sciences, Laboratory of Applied Chemistry, Faculty of Pharmacy, Porto University, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
National Institute of Legal Medicine and Forensic Sciences - North Branch, Jardim Carrilho Videira, 4050-167 Porto, Portugal; CENCIFOR - Forensic Science Center, Largo da Sé Nova, s/n, 3000-213 Coimbra, Portugal; Faculty of Medicine, Porto University, Al. Prof. Hernâni Monteiro, 4200-319 Porto, Portugal; School of Health Sciences, Minho University, Campus of Gualtar, 4710-057 Braga, Portugal.
J Trace Elem Med Biol. 2016 Dec;38:174-182. doi: 10.1016/j.jtemb.2016.03.018. Epub 2016 Apr 7.
The link between trace elements imbalances (both "toxic" and "essential") in the human brain and neurodegenerative disease has been subject of extensive research. More recently, some studies have highlighted the potential role of the homeostasis deregulation of alkali metals in specific brain regions as key factor in the pathogenesis of neurodegenerative diseases such as multiple sclerosis and Alzheimer's disease. Using flame atomic emission spectrometry and inductively coupled plasma-mass spectrometry after microwave-assisted acid digestion of the samples, alkali metals (Na, K, Li, Rb and Cs) were determined in 14 different areas of the human brain (frontal cortex, superior and middle temporal gyri, caudate nucleus, putamen, globus pallidus, cingulated gyrus, hippocampus, inferior parietal lobule, visual cortex of the occipital lobe, midbrain, pons, medulla and cerebellum) of adult individuals (n=42; 71±12, range: 50-101 years old) with no known history and evidence of neurodegenerative, neurological or psychiatric disorder. Potassium was found as the most abundant alkali metal, followed by Na, Rb, Cs and Li. Lithium, K and Cs distribution showed to be quite heterogeneous. On the contrary, Rb and Na appeared quite homogeneously distributed within the human brain tissue. The lowest levels of Na, K, Rb and Li were found in the brainstem (midbrain, medulla and pons) and cerebellum, while the lowest levels of Cs were found in the frontal cortex. The highest levels of K (mean±sd; range 15.5±2.5; 8.9-21.8mg/g) Rb (17.2±6.1; 3.9-32.4μg/g and Cs (83.4±48.6; 17.3-220.5ng/g) were found in putamen. The highest levels of Na and Li were found in the frontal cortex (11.6±2.4; 6.6-17.1mg/g) and caudate nucleus (7.6±4.6 2.2-21.3ng/g), respectively. Although K, Cs and Li levels appear to remain largely unchanged with age, some age-related changes were observed for Na and Rb levels in particular brain regions (namely in the hippocampus).
人脑中微量元素失衡（包括“有毒”和“必需”元素）与神经退行性疾病之间的联系一直是广泛研究的主题。最近，一些研究强调了特定脑区碱金属稳态失调作为多发性硬化症和阿尔茨海默病等神经退行性疾病发病机制中的关键因素的潜在作用。通过火焰原子发射光谱法和电感耦合等离子体质谱法对样品进行微波辅助酸消解后，测定了42名（年龄71±12岁，范围50 - 101岁）无神经退行性、神经或精神疾病病史及证据的成年个体人脑14个不同区域（额叶皮质、颞上回和颞中回、尾状核、壳核、苍白球、扣带回、海马体、顶下小叶、枕叶视觉皮质、中脑、脑桥、延髓和小脑）中的碱金属（钠、钾、锂、铷和铯）。发现钾是含量最丰富的碱金属，其次是钠、铷、铯和锂。锂、钾和铯的分布显示出相当的异质性。相反，铷和钠在人脑组织中分布较为均匀。钠、钾、铷和锂的最低水平出现在脑干（中脑、延髓和脑桥）和小脑中，而铯的最低水平出现在额叶皮质中。壳核中钾（均值±标准差；范围15.5±2.5；8.9 - 21.8mg/g）、铷（17.2±6.1；3.9 - 32.4μg/g）和铯（83.4±48.6；17.3 - 220.5ng/g）的水平最高。钠和锂的最高水平分别出现在额叶皮质（11.6±2.4；6.6 - 17.1mg/g）和尾状核（7.6±4.6；2.2 - 21.3ng/g）中。尽管钾、铯和锂的水平似乎在很大程度上不随年龄变化，但在特定脑区（即海马体）中观察到了钠和铷水平的一些与年龄相关的变化。
