Department of Psychiatry, Tohoku University Hospital, Sendai, Japan.
Department of Neuropsychiatry, School of Medicine, Fukushima Medical University, Fukushima, Japan.
Neuropsychopharmacol Rep. 2024 Jun;44(2):399-409. doi: 10.1002/npr2.12430. Epub 2024 Apr 1.
Postmortem brain research is necessary for elucidating the pathology of schizophrenia; an increasing number of studies require a combination of suitable tissue samples preserved at multiple brain banks. In this study, we examined whether a comparative study of protein expression levels can be conducted using postmortem brain samples preserved in different facilities.
We compared the demographic factors of postmortem brain samples preserved in two institutions and measured and compared the expression levels of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and glial fibrillary acidic protein (GFAP) in the prefrontal cortex and superior temporal gyrus. GAPDH is generally used as a loading control for western blotting, and GFAP is considered as an astrocyte marker in the brain.
We found significant differences between the two institutions in postmortem interval, age at death, and preservation time. To reduce the effects of these differences on our measurements, the parameters were set as covariates in our analyses of covariance. Subsequently, no differences in GAPDH and GFAP expression were found between institutions.
When studies are conducted using brain samples preserved in different brain banks, differences in demographic factors should be carefully considered and taken into account by statistical methods to minimize their impact as much as possible. Since there was no significant difference in the protein expression levels of GAPDH and GFAP in either region between the two institutions that preserved the postmortem brains, we concluded that it is possible to perform protein quantitative analysis assuming that there is no effect of difference between two institutions.
死后大脑研究对于阐明精神分裂症的病理学是必要的；越来越多的研究需要结合多个脑库保存的合适组织样本。在这项研究中，我们研究了使用保存在不同机构的死后脑组织样本是否可以进行蛋白质表达水平的比较研究。
我们比较了保存在两个机构的死后脑组织样本的人口统计学因素，并测量和比较了前额叶皮层和颞上回中甘油醛-3-磷酸脱氢酶（GAPDH）和胶质纤维酸性蛋白（GFAP）的表达水平。GAPDH 通常用作 Western blot 的加载对照，而 GFAP 被认为是大脑中的星形胶质细胞标志物。
我们发现两个机构之间在死后间隔、死亡时年龄和保存时间方面存在显著差异。为了减少这些差异对我们测量的影响，我们在协方差分析中将这些参数设置为协变量。随后，我们没有发现机构之间 GAPDH 和 GFAP 表达的差异。
当使用保存在不同脑库的脑组织样本进行研究时，应仔细考虑人口统计学因素的差异，并通过统计学方法考虑这些差异的影响，以尽可能地最小化其影响。由于保存在死后脑组织的两个机构之间 GAPDH 和 GFAP 在两个区域的蛋白表达水平没有显著差异，我们得出结论，在假设两个机构之间没有差异的情况下，可以进行蛋白定量分析。
