RT Journal Article
SR Electronic
T1 Distribution Features and Potential Effects of Serotonin in the Cerebrum of SOD1 G93A Transgenic Mice
JF eneuro
JO eNeuro
FD Society for Neuroscience
SP ENEURO.0001-22.2022
DO 10.1523/ENEURO.0001-22.2022
VO 9
IS 6
A1 Pei He
A1 Binjun He
A1 Shu Li
A1 Wen Chai
A1 Wei Rao
A1 Yu Zhu
A1 Wenzhi Chen
A1 Ping Zhang
A1 Xiong Zhang
A1 Haili Pan
A1 Renshi Xu
YR 2022
UL http://www.eneuro.org/content/9/6/ENEURO.0001-22.2022.abstract
AB Serotonin (5-HT) participates in the pathogenesis of amyotrophic lateral sclerosis (ALS), but its effects have not been completely clarified. Therefore, we observed the distribution features and potential effects of 5-HT in the cerebrum of G93A SOD1 transgenic (TG) and wild-type (WT) mice by fluorescence immunohistochemistry, Western blotting, ELISA, as well as motor function measurements. Both 5-HT and tryptophan hydroxylase-2 (TPH2) were mainly present in the limbic systems of the cerebrum, such as the glomerular layer of the olfactory bulb, nucleus accumbens, cingulate, fimbria of the hippocampus, mediodorsal thalamic nucleus, habenular nucleus, ventromedial hypothalamus nucleus, lateral hypothalamus area, dorsal raphe nucleus, and piriform cortex. TPH2 and 5-HT were expressed in cell bodies in the dorsal raphe nucleus and piriform cortex, while in other regions they were distributed as filaments and clump shapes in axons. The TPH2 distribution in the cerebrum of TG was significantly lower than that in WT in preset, onset, and progression stages. TPH2 expression in the fimbria of the hippocampus, mediodorsal thalamic nucleus, habenular nucleus, ventromedial hypothalamus nucleus and lateral hypothalamus area was increased in the onset stage and decreased in the progression stage, gradually decreased in the cingulate with disease progression and significantly decreased in the glomerular layer of the olfactory bulb and nucleus accumbens in the onset stage in TG. The number of mammalian achaete-scute homolog-1 in the subventricular zone (SVZ) in TG was significantly lower than that in WT, which was correlated with the TPH2 distribution. Double immunofluorescence staining showed that TPH2, mammalian achaete-scute homolog-1 and 5-HT were mainly expressed in neurons but rarely expressed in microglia or astrocytes in the piriform cortex. The relative fluorescence density of TPH2 in the cingulate region was negatively correlated with the disease severity. Our findings suggest that 5-HT plays a protective role in ALS, likely by regulating neural stem cells in the subventricular zone that might be involved in neuron development in the piriform cortex.