Free arachidonic acid source for PGE2 and TXB2 production in guinea pig peritoneal macrophages exposed to insoluble glucan from Streptococcus mutans.
1. Macrophages are an important source of the lipid mediators arachidonic acid (AA) and its metabolites that are produced during inflammation. 2. Previously, we reported that insoluble glucans from Streptococcus mutans in dental plaque could induce macrophages to secrete PGE2 and TXB2. 3. Studies were undertaken to identify the phospholipid substrates that can serve as a source of AA in macrophages exposed to the insoluble glucan. 4. When macrophage cell prelabelled with [3H]AA, stimulation with insoluble glucan resulted in a loss of label mainly from phosphatidylcholine (PC) and phosphatidylinositol (PI). 5. In addition, the PC-, and PI-specific phospholipase A2-mediated mechanisms for AA release may be activated in guinea peritoneal macrophages exposed to the insoluble glucan from S. mutans.
Shibata
Y
Y
Department of Biochemistry, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
Abiko
Y
Y
Ohishi
T
T
Tamaya
H
H
Takiguchi
H
H
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D002478:Cells, Cultured; D015232:Dinoprostone / Q000096:biosynthesis*; D005936:Glucans / Q000494:pharmacology*; D006168:Guinea Pigs; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D010743:Phospholipids / Q000378:metabolism; D011135:Polysaccharides, Bacterial / Q000494:pharmacology*; D012995:Solubility; D013295:Streptococcus mutans / Q000378:metabolism; D013929:Thromboxane B2 / Q000096:biosynthesis*
D001095:Arachidonic Acids; D005936:Glucans; D010743:Phospholipids; D011135:Polysaccharides, Bacterial; D016718:Arachidonic Acid; D013929:Thromboxane B2; D015232:Dinoprostone