title: Group IVA phospholipase A2 is associated with the storage of lipids in adipose tissue and liver.
abstract: Prostaglandin (PG) E(2) is considered to participate in the storage of fat in adipocytes and hepatocytes, but roles of group IVA phospholipase A(2) (PLA(2)), a key PLA(2) isozyme in the arachidonic acid cascade, remain unclear. The present study examined the possible involvement of the enzyme using group IVA PLA(2)-deficient mice (C57BL/6 background, 22 weeks of age) fed a normal diet (5.3% fat). The ratio of epididymal fat pad weight to body weight was significantly reduced in group IVA PLA(2)-deficient mice compared to wild-type mice. Histological analysis revealed that in group IVA PLA(2)-deficient mice, the adipocytes were smaller, and hepatocytes bearing cytoplasmic vacuolation were scarce. Hepatic triglyceride content and the serum levels of PGE(2) in the deficient mice were also lower. However, there was no difference in the serum levels of insulin, glucose, non-esterified free fatty acid, or total cholesterol between the deficient and wild-type mice. Our findings suggest that group IVA PLA(2) is involved in the storage of lipids in the adipose tissue and liver and in determining circulating PGE(2) levels.
authors.affiliation: Department of Pathological Biochemistry, Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Ii
authors.forename: Shinji
authors.initials: S
authors.lastname: Hatakeyama
authors.forename: Kae
authors.initials: K
authors.lastname: Tsutsumi
authors.forename: Takashi
authors.initials: T
authors.lastname: Sato
authors.forename: Satoshi
authors.initials: S
authors.lastname: Akiba
mesh_terms: D017667:Adipocytes / Q000166:cytology / Q000378:metabolism; D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D015153:Blotting, Western; D001835:Body Weight; D015232:Dinoprostone / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005230:Fatty Acids, Nonesterified / Q000097:blood; D054513:Group IV Phospholipases A2 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D007328:Insulin / Q000097:blood; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis*; D008099:Liver / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D014280:Triglycerides / Q000097:blood
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D008055:Lipids; D014280:Triglycerides; D054513:Group IV Phospholipases A2; D015232:Dinoprostone