Conjugated linoleic acids can change phagocytosis of human monocytes/macrophages by reduction in Cox-2 expression.
Prostaglandin E2 produced endogenously (by cyclooxygenases) can regulate macrophage phagocytosis. Cyclooxygenase activity reduction (mainly through inhibition of inducible Cox-2) can induce PGE2 synthesis depression and can activate the phagocytosis process. There are no reports in the literature explaining whether conjugated linoleic acid dienes (trans-10, cis-12 CLA and cis-9, trans-11 CLA) modify the phagocytic activity of human macrophages. For the purpose of this study, monocytes were isolated from venous blood, incubated for 7 days with 30 microM CLAs, and then (in some experiments) LPS (1 microg/mL) was added to the medium. Subsequently, monocyte/macrophage phagocytosis, NF-kappaB transcription factor activity, Cox-2 and PPARgamma mRNA expression (and the amounts of Cox-2 and PPARgamma proteins) and PGE2 synthesis were determined. Both CLA isomers increased macrophage phagocytosis through inhibition of Cox-2 expression (might by inactivation the NF-kappaB pathway). The inhibition of mRNA Cox-2 expression contributed (particularly with respect to trans-10, cis-12 CLA) to a decrease in protein Cox-2 synthesis and to reduction of prostaglandin E2 content in the cell. The inhibition of PGE2 synthesis (by CLA treatment) enhanced the phagocytosis process in macrophages.
Stachowska
Ewa
E
Department of Biochemistry, Pomeranian Medical University, Szczecin, Poland. ewast@sci.pam.szczecin.pl
Baśkiewicz-Masiuk
Magdalena
M
Dziedziejko
Violetta
V
Adler
Grazyna
G
Bober
Joanna
J
Machaliński
Bogusław
B
Chlubek
Dariusz
D
D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism*; D015232:Dinoprostone / Q000096:biosynthesis; D005260:Female; D006801:Humans; D044243:Linoleic Acids, Conjugated / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D016328:NF-kappa B / Q000378:metabolism; D047495:PPAR gamma / Q000235:genetics / Q000378:metabolism; D010587:Phagocytosis; D012333:RNA, Messenger / Q000378:metabolism
D044243:Linoleic Acids, Conjugated; D016328:NF-kappa B; D047495:PPAR gamma; D012333:RNA, Messenger; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D015232:Dinoprostone