Entorhinal deafferentation induces upregulation of SPARC in the mouse hippocampus.
SPARC is a matricellular protein that modulates cell-cell and cell-matrix interactions by virtue of its antiproliferative and counteradhesive properties. Here, we report the denervation-induced upregulation of SPARC mRNA and protein in the mouse hippocampus following transections of the entorhinal afferents. Northern blot analysis showed that SPARC mRNA was upregulated in a transient manner in the deafferented mouse hippocampus. In situ hybridization and immunohistochemistry confirmed the temporal upregulation of both SPARC mRNA and protein specifically in the denervated areas, which initiated at 7 days postlesion, reached the maximum at 15 as well as 30 days postlesion, and subsided towards normal levels by 60 days postlesion. Double labeling by either a combination of in situ hybridization for SPARC mRNA with immunohistochemistry for glial fibrillary acidic protein or double immunofluorescence staining for both proteins in the hippocampus revealed that SPARC-expressing cells are reactive astrocytes. In respect to the spatiotemporal alterations of SPARC expression in the denervated hippocampus, we suggest that SPARC may be involved in modulation of the denervation-induced plasticity processes such as glial cell proliferation, axonal sprouting and subsequent synaptogenesis in the hippocampus following entorhinal deafferentation.
Liu
Xin
X
Key Laboratory of Neurobiology, Shanghai Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Science, 320 Yue-Yang Road, Shanghai 200031, PR China.
Ying
Guoxin
G
Wang
Wenyuan
W
Dong
Jinghui
J
Wang
Yan
Y
Ni
Zimei
Z
Zhou
Changfu
C
D000344:Afferent Pathways / Q000378:metabolism / Q000473:pathology; D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism; D003714:Denervation; D018728:Entorhinal Cortex / Q000166:cytology / Q000502:physiology; D005260:Female; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D017403:In Situ Hybridization; D051379:Mice; D015676:Osteonectin / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D015854:Up-Regulation
D015676:Osteonectin; D012333:RNA, Messenger