Anderson Joel G, Cooney Paula T, Erikson Keith M
Department of Nutrition, The University of North Carolina at Greensboro, Greensboro, North Carolina 27402, USA.
Toxicol Sci. 2007 Jan;95(1):188-95. doi: 10.1093/toxsci/kfl130. Epub 2006 Oct 10.
Iron (Fe) is an essential trace metal involved in numerous cellular processes. Iron deficiency (ID) is reported as the most prevalent nutritional problem worldwide. Increasing evidence suggests that ID is associated with altered neurotransmitter metabolism and a risk factor for manganese (Mn) neurotoxicity. Though recent studies have established differences in which the female brain responds to ID-related neurochemical alterations versus the male brain, little is known about the interactions of dietary ID, Mn exposure, and sex on gamma-amino butyric acid (GABA). Male and female Sprague-Dawley rats were randomly divided into four dietary treatment groups: control (CN), control/Mn supplemented, ID, and ID/Mn supplemented. After 6 weeks of treatment, both ID diets caused a highly significant decrease in Fe concentrations across all brain regions compared to CN in both sexes. Both ID and Mn supplementation led to significant accumulation of Mn across all brain regions in both sexes. There was no main effect of sex on Fe or Mn accumulation. Striatal synaptosomes were utilized to examine the effect of dietary intervention on (3)H-GABA uptake. At 4 weeks, there was a significant correlation between Fe concentration and (3)H-GABA uptake in male rats (p < 0.05). At 6 weeks, there was a significant inverse correlation between Mn concentration and (3)H-GABA uptake in male and female rats and a postitive correlation between Fe concentration and (3)H-GABA uptake in female rats (p < 0.05). In conclusion, ID-associated Mn accumulation is similar in both sexes, with Mn levels affecting GABA uptake in both sexes in a comparable fashion.
铁（Fe）是一种参与众多细胞过程的必需微量元素。据报道，缺铁（ID）是全球最普遍的营养问题。越来越多的证据表明，缺铁与神经递质代谢改变以及锰（Mn）神经毒性的危险因素有关。尽管最近的研究已经确定了雌性大脑与雄性大脑对缺铁相关神经化学改变的反应存在差异，但关于饮食缺铁、锰暴露和性别对γ-氨基丁酸（GABA）的相互作用知之甚少。将雄性和雌性Sprague-Dawley大鼠随机分为四个饮食治疗组：对照组（CN）、补充对照/Mn组、缺铁组和补充缺铁/Mn组。治疗6周后，与两性的对照组相比，两种缺铁饮食均导致所有脑区的铁浓度显著降低。缺铁和补充锰均导致两性所有脑区的锰显著积累。性别对铁或锰的积累没有主要影响。利用纹状体突触体来检测饮食干预对（3）H-GABA摄取的影响。在4周时，雄性大鼠的铁浓度与（3）H-GABA摄取之间存在显著相关性（p < 0.05）。在6周时，雄性和雌性大鼠的锰浓度与（3）H-GABA摄取之间存在显著负相关，而雌性大鼠的铁浓度与（3）H-GABA摄取之间存在正相关（p < 0.05）。总之，缺铁相关的锰积累在两性中相似，锰水平以类似方式影响两性的GABA摄取。
