Effects of low temperatures on proliferation-related signaling pathways in the hippocampus after traumatic brain injury.
To evaluate the influence of low temperatures on the proliferation of neural stem cells (NSCs) and the regulation of their signaling pathways after brain trauma, we examined changes in the expression levels of specific miRNAs and their target genes. We also evaluated NSC proliferation in the hippocampus after brain trauma under low-temperature conditions. We found that the expression profile of miRNAs in the hippocampus after trauma changed at both normal and low temperatures, and the expression of miR-34a decreased significantly lower in rats exposed to low temperatures. There was significant proliferation of endogenous NSCs in the hippocampus after brain trauma at both temperatures, but NSC proliferation was slower at low temperatures. In addition, the expression of Notch1 significantly increased in the hippocampus after brain trauma at both temperatures. However, at low temperatures, the degree of up-regulation of Notch signaling molecules was significantly lower. We conclude that low-temperature environments can inhibit the proliferation of endogenous NSCs in the hippocampus, possibly by alleviating the effects of miR-34a down-regulation and Notch signaling up-regulation induced by traumatic brain injury.
Institute of Orthopaedic Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, China.
Yang
Y
Wang
Fei
F
Guo
Changfu
C
Pan
Yuanlei
Y
Lou
Pengqi
P
Zhang
Shangchun
S
Guo
Junhui
J
Yin
Zhifeng
Z
Deng
D000818:Animals; D001930:Brain Injuries / Q000378:metabolism* / Q000473:pathology; D049109:Cell Proliferation; D003080:Cold Temperature; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D035683:MicroRNAs / Q000096:biosynthesis; D058953:Neural Stem Cells / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D051881:Receptor, Notch1 / Q000378:metabolism; D015398:Signal Transduction
C551848:MIRN34a microRNA, mouse; D035683:MicroRNAs; C497762:Notch1 protein, mouse; D051881:Receptor, Notch1