Department of Radiology, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA.
Autism Res. 2013 Feb;6(1):1-10. doi: 10.1002/aur.1260. Epub 2012 Nov 16.
Increased glutamate levels have been reported in the hippocampal and frontal regions of persons with autism using proton magnetic resonance spectroscopy ((1)H-MRS). Although autism spectrum disorders (ASDs) are highly heritable, MRS studies have not included relatives of persons with ASD. We therefore conducted a study to determine if glutamate levels are elevated in people with autism and parents of children with autism. Single-voxel, point-resolved spectroscopy data were acquired at 3T for left and right hemisphere auditory cortical voxels in 13 adults with autism, 15 parents of children with autism, and 15 adult control subjects. The primary measure was glutamate + glutamine (Glx). Additional measures included n-acetyl-aspartate (NAA), choline (Cho), myoinositol (mI), and creatine (Cr). The autism group had significantly higher Glx, NAA, and Cr concentrations than the control subjects. Parents did not differ from control subjects on any measures. No significant differences in Cho or mI levels were seen among groups. No reliable correlations between autism symptom measures, and MRS variables were seen after Bonferroni correction for multiple comparisons. The elevation in Glx in autism is consistent with prior MRS data in the hippocampus and frontal lobe and may suggest increased cortical excitability. Increased NAA and Cr may indicate brain metabolism disturbances in autism. In the current study, we found no reliable evidence of a familial effect for any spectroscopy measure. This may indicate that these metabolites have no heritable component in autism, the presence of a compensatory factor in parents, or sample-specific limitations such as the participation of singleton families.
使用质子磁共振波谱（1H-MRS）的研究报告称，自闭症患者的海马体和额叶区域谷氨酸水平升高。尽管自闭症谱系障碍（ASD）具有高度遗传性，但 MRS 研究并未包括 ASD 患者的亲属。因此，我们进行了一项研究，以确定自闭症患者和自闭症儿童的父母的谷氨酸水平是否升高。在 13 名自闭症成年人、15 名自闭症儿童的父母和 15 名成年对照组中，在 3T 上采集了左、右半球听觉皮质体素的单体分辨光谱数据。主要测量指标为谷氨酸+谷氨酰胺（Glx）。其他测量指标包括 N-乙酰天冬氨酸（NAA）、胆碱（Cho）、肌醇（mI）和肌酸（Cr）。自闭症组的 Glx、NAA 和 Cr 浓度明显高于对照组。父母在任何指标上均与对照组无差异。各组间 Cho 或 mI 水平无显著差异。在经过多次比较的 Bonferroni 校正后，自闭症症状测量值与 MRS 变量之间未见可靠相关性。自闭症中的 Glx 升高与先前在海马体和额叶的 MRS 数据一致，可能表明皮质兴奋性增加。NAA 和 Cr 的增加可能表明自闭症中存在脑代谢紊乱。在本研究中，我们没有发现任何与光谱测量值相关的家族效应的可靠证据。这可能表明这些代谢物在自闭症中没有遗传成分，父母中存在补偿因素，或者是样本特异性限制，如单亲家庭的参与。
