正常老化过程中海马不同部位代谢物浓度与年龄的相关性

摘要

Objective To evaluate the metabolism change with aging brain in the different regions of the bilateral hippocampal using 1 H magnetic resonance spectroscopy(1 H-MRS),and to further investigate the correlation between metabolites,metabolite concentrations ratio and age. Methods Brain conventional MRI,MRS were employed in 121 right-handed healthy volunteers. After selecting the regions of interest artificially,the required parameters N-acetyl-aspartate (NAA),choline compounds(Cho),creatine(Cr)were measured by the machine automatically.The parameters between genders and ages were compared.Pearson correlation analysis was used to further investigate the correlation between the concentrations of NAA,Cho,Cr and age in different regions of the hippocampus.Results No significant gender effects were found in the concentrations of NAA,Cho,Cr(P >0.05 ).A significant age effects were found in the concentrations of NAA in the hippocampal head,body(body 1 area,body 2 area)and tail.The concentrations of NAA in the above regions of elderly group decreased significantly as compared with young and elderly group(P <0.05),while NAA showed significant changes between young and middle aged group in the hippocampal head,body(body 1 area,body 2 area)and tail(P >0.05 ).No significant age-associated changes were observed in Cho,Cr.Only the NAA concentrations were negatively correlated with age in bilateral hippocampal head,body(body 1 area,2 area),and tail(P <0.05).No significant age-associated changes were observed in Cho,Cr (P >0.05).Conclusion The NAA concentration decreased with age in the different regions of the hippocampus during normal brain aging.The NAA concentration in elderly group is significantly lower than that of young and middle aged group.No significant differences are found in the concentrations of NAA,Cho,Cr between genders.%目的：利用氢质子磁共振波谱分析（1 H magnetic resonance spectroscopy，1 H-MRS）技术，评价正常脑老化过程中双侧海马不同部位代谢物浓度的变化，并进一步探讨代谢物浓度与年龄的相关性。方法121例健康右利手志愿者，行颅脑常规磁共振成像（magnetic resonance imaging，MRI）、磁共振波谱（magnetic resonance spectroscopy，MRS）检查，人为确定 MRS 感兴趣区，机器自动测量海马不同部位浓度值参数：N-乙酰天门冬氨酸（N-acetyl-aspartate，NAA）、胆碱（choline compounds，Cho）、肌酸（creatine，Cr）。比较不同性别、不同年龄组间各参数的差异。分析海马各部位 NAA、Cho、Cr 与年龄的相关性。结果不同性别间海马各部位 NAA、Cho、Cr 比较差异无统计学意义（P ＞0．05）。不同年龄组间双侧海马头、体（体1、体2）、尾部 NAA 值差异有统计学意义，老年组双侧海马头、体（体1 区、体2 区）、尾部 NAA 显著低于青年组和中年组（P ＜0．05），青年组与中年组比较差异无统计学意义（P ＞0．05）；不同年龄组间 Cho、Cr 差异无统计学意义（P ＞0．05）。双侧海马头、体（体1、体2 区）、尾部仅NAA 与年龄呈负相关（P ＜0．05），Cho、Cr 与年龄无相关性（P ＞0．05）。结论正常脑老化过程中海马各部位 NAA值随年龄增长而降低，老年组明显低于青年组及中年组。海马各部位 NAA、Cho、Cr 值无性别差异。