Mitogenic stimulation of primary cultures of lung epithelial cells by linoleic acid.
The role of linoleic acid (18:2 n-6) in stimulating proliferation of normal lung epithelial cells in vitro is investigated. When 18:2 n-6 is present with insulin (I) and cholera toxin (CT), growth is stimulated synergistically. In the presence of indomethacin (10 mu M), an inhibition of proliferation is observed in I,CT, and 18:2 n-6, which can be reversed by the addition of exogenous prostaglandin E(2) (PGE(2)). Incorporation of [(14)C]18:2 n-6 with lipid-independent I, CT, and cortisol and lipid-dependent I, CT, and 18:2 n-6 conditions suggests differences in mobilization of 18:2 n-6 from the phospholipid (PL) fractions between 2 and 8 days. The decline of [(14)C]18:2 n-6 in PL fractions with lipid-dependent condition suggests that free 18:2 n-6 may be available for metabolism by the cyclooxygenase pathway. In non-proliferative cultures, an accumulation of the label in the PL fraction is observed. Proliferation in lipid-dependent conditions appears to be due to the mobilization of 18:2 n-6 whereas proliferation in lipid-independent conditions appears to be independently controlled.
Usha
S
S
Centre for Biotechnology, Anna University, Madras, India.
Maya
A
A
Balakrishnan
A
A
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects; D002772:Cholera Toxin / Q000494:pharmacology; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D004041:Dietary Fats / Q000494:pharmacology; D015232:Dinoprostone / Q000494:pharmacology; D004357:Drug Synergism; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects; D006131:Growth Inhibitors / Q000494:pharmacology; D006133:Growth Substances / Q000494:pharmacology; D006854:Hydrocortisone / Q000494:pharmacology; D007213:Indomethacin / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000494:pharmacology*; D008168:Lung / Q000166:cytology / Q000187:drug effects*; D008934:Mitogens / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013047:Specific Pathogen-Free Organisms
D016895:Culture Media, Serum-Free; D004041:Dietary Fats; D006131:Growth Inhibitors; D006133:Growth Substances; D007328:Insulin; D008041:Linoleic Acids; D008934:Mitogens; D002772:Cholera Toxin; D019787:Linoleic Acid; D015232:Dinoprostone; D006854:Hydrocortisone; D007213:Indomethacin