TY - JOUR
T1 - Temporal changes in innate immune signals in a rat model of alcohol withdrawal in emotional and cardiorespiratory homeostatic nuclei
AU - Freeman, Kate
AU - Brureau, Anthony
AU - Vadigepalli, Rajanikanth
AU - Staehle, Mary M.
AU - Brureau, Melanie M.
AU - Gonye, Gregory E.
AU - Hoek, Jan B.
AU - Hooper, D. C.
AU - Schwaber, James S.
N1 - Funding Information:
This work was supported by grants from the National Institutes of Health (NIH) (R01 AA-015601, R01 GM-076495 and R33 HL-087361 to JSS; GM-083108 to JSS and RV; R33 HL088283 to RV; R24 AA-014986 to JBH; and T32 AA-007463 support of KF and MMS). The qRT-PCR was performed with generous help from Carmen N. Nichols, PhD and Haisun Zhu, PhD. We also wish to thank Prudhvi Mummaneni and James Park for their assistance with analysis and the TJU Alcohol Research Center, especially Dr. Biddanda Ponnappa, John Mullen, and Permelia Mullen, for their support with the animal model.
PY - 2012/5/24
Y1 - 2012/5/24
N2 - Background: Chronic alcohol use changes the brain's inflammatory state. However, there is little work examining the progression of the cytokine response during alcohol withdrawal, a period of profound autonomic and emotional upset. This study examines the inflammatory response in the central nucleus of the amygdala (CeA) and dorsal vagal complex (DVC), brain regions neuroanatomically associated with affective and cardiorespiratory regulation in an in vivo rat model of withdrawal following a single chronic exposure.Methods: For qRT-PCR studies, we measured the expression of TNF-α, NOS-2, Ccl2 (MCP-1), MHC II invariant chain CD74, and the TNF receptor Tnfrsf1a in CeA and DVC samples from adult male rats exposed to a liquid alcohol diet for thirty-five days and in similarly treated animals at four hours and forty-eight hours following alcohol withdrawal. ANOVA was used to identify statistically significant treatment effects. Immunohistochemistry (IHC) and confocal microscopy were performed in a second set of animals during chronic alcohol exposure and subsequent 48-hour withdrawal.Results: Following a chronic alcohol exposure, withdrawal resulted in a statistically significant increase in the expression of mRNAs specific for innate immune markers Ccl2, TNF-α, NOS-2, Tnfrsf1a, and CD74. This response was present in both the CeA and DVC and most prominent at 48 hours. Confocal IHC of samples taken 48 hours into withdrawal demonstrate the presence of TNF-α staining surrounding cells expressing the neural marker NeuN and endothelial cells colabeled with ICAM-1 (CD54) and RECA-1, markers associated with an inflammatory response. Again, findings were consistent in both brain regions.Conclusions: This study demonstrates the rapid induction of Ccl2, TNF-α, NOS-2, Tnfrsf1a and CD74 expression during alcohol withdrawal in both the CeA and DVC. IHC dual labeling showed an increase in TNF-α surrounding neurons and ICAM-1 on vascular endothelial cells 48 hours into withdrawal, confirming the inflammatory response at the protein level. These findings suggest that an abrupt cessation of alcohol intake leads to an acute central nervous system (CNS) inflammatory response in these regions that regulate autonomic and emotional state.
AB - Background: Chronic alcohol use changes the brain's inflammatory state. However, there is little work examining the progression of the cytokine response during alcohol withdrawal, a period of profound autonomic and emotional upset. This study examines the inflammatory response in the central nucleus of the amygdala (CeA) and dorsal vagal complex (DVC), brain regions neuroanatomically associated with affective and cardiorespiratory regulation in an in vivo rat model of withdrawal following a single chronic exposure.Methods: For qRT-PCR studies, we measured the expression of TNF-α, NOS-2, Ccl2 (MCP-1), MHC II invariant chain CD74, and the TNF receptor Tnfrsf1a in CeA and DVC samples from adult male rats exposed to a liquid alcohol diet for thirty-five days and in similarly treated animals at four hours and forty-eight hours following alcohol withdrawal. ANOVA was used to identify statistically significant treatment effects. Immunohistochemistry (IHC) and confocal microscopy were performed in a second set of animals during chronic alcohol exposure and subsequent 48-hour withdrawal.Results: Following a chronic alcohol exposure, withdrawal resulted in a statistically significant increase in the expression of mRNAs specific for innate immune markers Ccl2, TNF-α, NOS-2, Tnfrsf1a, and CD74. This response was present in both the CeA and DVC and most prominent at 48 hours. Confocal IHC of samples taken 48 hours into withdrawal demonstrate the presence of TNF-α staining surrounding cells expressing the neural marker NeuN and endothelial cells colabeled with ICAM-1 (CD54) and RECA-1, markers associated with an inflammatory response. Again, findings were consistent in both brain regions.Conclusions: This study demonstrates the rapid induction of Ccl2, TNF-α, NOS-2, Tnfrsf1a and CD74 expression during alcohol withdrawal in both the CeA and DVC. IHC dual labeling showed an increase in TNF-α surrounding neurons and ICAM-1 on vascular endothelial cells 48 hours into withdrawal, confirming the inflammatory response at the protein level. These findings suggest that an abrupt cessation of alcohol intake leads to an acute central nervous system (CNS) inflammatory response in these regions that regulate autonomic and emotional state.
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U2 - 10.1186/1742-2094-9-97
DO - 10.1186/1742-2094-9-97
M3 - Article
C2 - 22626265
AN - SCOPUS:84861329347
SN - 1742-2094
VL - 9
JO - Journal of Neuroinflammation
JF - Journal of Neuroinflammation
M1 - 598
ER -