TY - JOUR
T1 - Serum Amyloid A is Expressed in the Brain After Traumatic Brain Injury in a Sex-Dependent Manner
AU - Soriano, Sirena
AU - Moffet, Bridget
AU - Wicker, Evan
AU - Villapol, Sonia
N1 - Funding Information:
This work was supported by R03NS095038 (SV) grant from the National Institute for Neurological Disorders and Stroke (NINDS), and funds from Houston Methodist Research Institute.
Funding Information:
We thank the master?s degree in Biochemistry and Molecular Biology Program at Georgetown University for the support.
Publisher Copyright:
© 2020, Springer Science+Business Media, LLC, part of Springer Nature.
PY - 2020/10/1
Y1 - 2020/10/1
N2 - Serum amyloid A (SAA) is an acute phase protein upregulated in the liver after traumatic brain injury (TBI). So far, it has not been investigated whether SAA expression also occurs in the brain in response to TBI. For this, we performed a moderate controlled cortical impact injury in adult male and female mice and analyzed brain, blood, and liver samples at 6 h, 1, 3, and 10 days post-injury (dpi). We measured the levels of SAA in serum, brain and liver by western blot. We also used immunohistochemical techniques combined with in situ hybridization to determine SAA mRNA and protein expression in the brain. Our results revealed higher levels of SAA in the bloodstream in males compared to females at 6 h post-TBI. Liver and serum SAA protein showed a peak of expression at 1 dpi followed by a decrease at 3 to 10 dpi in both sexes. Both SAA mRNA and protein expression colocalize with astrocytes and macrophages/microglia in the cortex, corpus callosum, thalamus, and hippocampus after TBI. For the first time, here we show that SAA is expressed in the brain in response to TBI. Collectively, SAA expression was higher in males compared to females, and in association with the sex-dependent neuroinflammatory response after brain injury. We suggest that SAA could be a crucial protein associated to the acute neuroinflammation following TBI, not only for its hepatic upregulation but also for its expression in the injured brain.
AB - Serum amyloid A (SAA) is an acute phase protein upregulated in the liver after traumatic brain injury (TBI). So far, it has not been investigated whether SAA expression also occurs in the brain in response to TBI. For this, we performed a moderate controlled cortical impact injury in adult male and female mice and analyzed brain, blood, and liver samples at 6 h, 1, 3, and 10 days post-injury (dpi). We measured the levels of SAA in serum, brain and liver by western blot. We also used immunohistochemical techniques combined with in situ hybridization to determine SAA mRNA and protein expression in the brain. Our results revealed higher levels of SAA in the bloodstream in males compared to females at 6 h post-TBI. Liver and serum SAA protein showed a peak of expression at 1 dpi followed by a decrease at 3 to 10 dpi in both sexes. Both SAA mRNA and protein expression colocalize with astrocytes and macrophages/microglia in the cortex, corpus callosum, thalamus, and hippocampus after TBI. For the first time, here we show that SAA is expressed in the brain in response to TBI. Collectively, SAA expression was higher in males compared to females, and in association with the sex-dependent neuroinflammatory response after brain injury. We suggest that SAA could be a crucial protein associated to the acute neuroinflammation following TBI, not only for its hepatic upregulation but also for its expression in the injured brain.
KW - Acute phase response
KW - Brain trauma
KW - Microglia
KW - Neuroinflammation
KW - Neutrophil accumulation
UR - http://www.scopus.com/inward/record.url?scp=85079464732&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85079464732&partnerID=8YFLogxK
U2 - 10.1007/s10571-020-00808-3
DO - 10.1007/s10571-020-00808-3
M3 - Article
C2 - 32060858
AN - SCOPUS:85079464732
SN - 0272-4340
VL - 40
SP - 1199
EP - 1211
JO - Cellular and Molecular Neurobiology
JF - Cellular and Molecular Neurobiology
IS - 7
ER -