TY - JOUR
T1 - Brain oxylipin concentrations following hypercapnia/ ischemia
T2 - Effects of brain dissection and dissection time
AU - Hennebelle, Marie
AU - Metherel, Adam H.
AU - Kitson, Alex P.
AU - Otoki, Yurika
AU - Yang, Jun
AU - Lee, Kin Sing Stephen
AU - Hammock, Bruce D.
AU - Bazinet, Richard P.
AU - Taha, Ameer Y.
N1 - Funding Information:
This study was supported by USDA National Institute of Food and Agriculture Hatch Project 1008787; the University of California, Davis Department of Food Science and Technology and College of Agriculture and Environmental Sciences (A.Y.T.); Natural Sciences and Engineering Research Council of Canada Grant 482597 (R.P.B.); National Institute of Environmental Health Sciences Grant R01 ES002710; and National Institute of Environmental Health Sciences Superfund Research Program Grant P42 ES004699 (B.D.H.); and National Institute of Environmental Health Sciences Grant R00 ES024806 (K.S.S.L.). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The authors declare no conflict of interest. Manuscript received 8 February 2018 and in revised form 12 October 2018. Published, JLR Papers in Press, November 21, 2018 DOI https://doi.org/10.1194/jlr.D084228
Funding Information:
This study was supported by USDA National Institute of Food and Agriculture Hatch Project 1008787; the University of California, Davis Department of Food Science and Technology and College of Agriculture and Environmental Sciences (A.Y.T.); Natural Sciences and Engineering Research Council of Canada Grant 482597 (R.P.B.); National Institute of Environmental Health Sciences Grant R01 ES002710; and National Institute of Environmental Health Sciences Superfund Research Program Grant P42 ES004699 (B.D.H.); and National Institute of Environmental Health Sciences Grant R00 ES024806 (K.S.S.L.). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The authors declare no conflict of interest.
Publisher Copyright:
© 2019 Hennebelle et al.
PY - 2019
Y1 - 2019
N2 - PUFAs are precursors to bioactive oxylipin metabolites that increase in the brain following CO2-induced hypercapnia/ischemia. It is not known whether the brain-dissection process and its duration also alter these metabolites. We applied CO2 with or without head-focused microwave fixation for 2 min to evaluate the effects of CO2-induced asphyxiation, dissection, and dissection time on brain oxylipin concentrations. Compared with head-focused microwave fixation (control), CO2 followed by microwave fixation prior to dissection increased oxylipins derived from lipoxygenase (LOX), 15-hydroxyprostaglandin dehydrogenase (PGDH), cytochrome P450 (CYP), and soluble epoxide hydrolase (sEH) enzymatic pathways. This effect was enhanced when the duration of postmortem ischemia was prolonged by 6.4 min prior to microwave fixation. Brains dissected from rats subjected to CO2 without microwave fixation showed greater increases in LOX, PGDH, CYP and sEH metabolites compared with all other groups, as well as increased cyclooxygenase metabolites. In nonmicrowave-irradiated brains, sEH metabolites and one CYP metabolite correlated positively and negatively with dissection time, respectively. This study presents new evidence that the dissection process and its duration increase brain oxylipin concentrations, and that this is preventable by microwave fixation. When microwave fixation is not available, lipidomic studies should account for dissection time to reduce these artifacts.
AB - PUFAs are precursors to bioactive oxylipin metabolites that increase in the brain following CO2-induced hypercapnia/ischemia. It is not known whether the brain-dissection process and its duration also alter these metabolites. We applied CO2 with or without head-focused microwave fixation for 2 min to evaluate the effects of CO2-induced asphyxiation, dissection, and dissection time on brain oxylipin concentrations. Compared with head-focused microwave fixation (control), CO2 followed by microwave fixation prior to dissection increased oxylipins derived from lipoxygenase (LOX), 15-hydroxyprostaglandin dehydrogenase (PGDH), cytochrome P450 (CYP), and soluble epoxide hydrolase (sEH) enzymatic pathways. This effect was enhanced when the duration of postmortem ischemia was prolonged by 6.4 min prior to microwave fixation. Brains dissected from rats subjected to CO2 without microwave fixation showed greater increases in LOX, PGDH, CYP and sEH metabolites compared with all other groups, as well as increased cyclooxygenase metabolites. In nonmicrowave-irradiated brains, sEH metabolites and one CYP metabolite correlated positively and negatively with dissection time, respectively. This study presents new evidence that the dissection process and its duration increase brain oxylipin concentrations, and that this is preventable by microwave fixation. When microwave fixation is not available, lipidomic studies should account for dissection time to reduce these artifacts.
KW - Brain lipids
KW - Lipid mediators
KW - Polyunsaturated fatty acid metabolites
UR - http://www.scopus.com/inward/record.url?scp=85064282504&partnerID=8YFLogxK
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U2 - 10.1194/jlr.D084228
DO - 10.1194/jlr.D084228
M3 - Article
C2 - 30463986
AN - SCOPUS:85064282504
SN - 0022-2275
VL - 60
SP - 671
EP - 682
JO - Journal of Lipid Research
JF - Journal of Lipid Research
IS - 3
ER -