title: Methylene blue protection against hypoxic injury in primary cultures of rat hepatocyte monolayers.
abstract: Mitochondrial respiration is inhibited in cells exposed to hypoxia, and the oxidation of NADH to NAD(+) is blocked. As a result, oxidation reactions requiring NAD(+) are blocked, disrupting cellular metabolism. We studied the influence of methylene blue, which oxidizes NADH, on hypoxic damage to primary cultures of rat hepatocyte monolayers. During hypoxic treatment of hepatocytes, aspartate aminotransferase leaked out of the cells into the culture medium. However, addition of methylene blue to the medium repressed the hypoxic leakage of the enzyme. The exposure of hepatocytes to hypoxia decreased the acetoacetate/beta-hydroxybutyrate ratio which reflects the redox state of the cell. The level of the acetoacetate/beta-hydroxybutyrate ratio in hypoxic cells was increased by the addition of methylene blue. These results suggest that methylene blue protects against hypoxic injury due to its oxidation of NADH.
authors.affiliation: Department of Clinical Biochemistry, School of Health Sciences, Kyorin University, Hachioji, Tokyo, Japan. mhypoxia@kyorin-u.ac.jp
authors.forename: Haruhiro
authors.initials: H
authors.lastname: Muratsubaki
authors.forename: Nozomi
authors.initials: N
authors.lastname: Yajima
authors.forename: Hitomi
authors.initials: H
authors.lastname: Yoneda
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Enomoto
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Tezuka
mesh_terms: D000818:Animals; D015687:Cell Hypoxia / Q000187:drug effects* / Q000502:physiology*; D002478:Cells, Cultured; D019610:Cytoprotection / Q000187:drug effects*; D022781:Hepatocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D008751:Methylene Blue / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D008751:Methylene Blue