Mycoplasma fermentans glycolipid triggers inflammatory response in rat astrocytes.
Mycoplasma fermentans glycolipid (MfGL-II) is a major lipid in the membranes of this AIDS-associated mycoplasma and constituting up to 20% of the total phospholipids of this organism. It was recently shown that MfGL-II, mainly through its phosphocholine moiety, is responsible for the attachment of M. fermentans to host cells. We now show that MfGL-II is also associated with the secretion of inflammatory mediators by cells of the central nervous system. Stimulation of primary rat astrocytes by MfGL-II caused activation of protein kinase C, secretion of nitric oxide (NO) and prostaglandin E2, and augmented glucose utilization and lactate formation in a dose-dependent manner. In an attempt to define the minimal structural requirements for MfGL-II activity, the two O-acylated fatty acids in the molecule were removed. Deacylation pronouncedly reduced the stimulatory activity of the glycolipid, suggesting that the fatty acyl residues are essential. Incubation of MfGL-II with polyclonal anti-MfGL-II antiserum or with monoclonal anti-phosphocholine antibody diminished NO release, whereas incubation of MfGL-II with normal rabbit serum had no effect. It is, therefore, likely that the terminal phosphocholine moiety plays an important role in MfGL-IIs stimulation of glial cells.
Ben-Menachem
G
G
Department of Membrane and Ultrastructure Research, The Hebrew University-Hadassah Medical School, P.O. Box 12272, Jerusalem, Israel.
Rottem
S
S
Tarshis
M
M
Barash
V
V
Brenner
T
T
D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*; D001921:Brain / Q000166:cytology / Q000201:enzymology; D002478:Cells, Cultured; D015232:Dinoprostone / Q000096:biosynthesis / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects / Q000276:immunology; D005333:Fetus; D005947:Glucose / Q000378:metabolism; D006017:Glycolipids / Q000276:immunology* / Q000494:pharmacology*; D007249:Inflammation / Q000276:immunology*; D019344:Lactic Acid / Q000096:biosynthesis; D016858:Mycoplasma fermentans / Q000737:chemistry / Q000276:immunology*; D009457:Neuroglia / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D009569:Nitric Oxide / Q000096:biosynthesis; D011493:Protein Kinase C / Q000032:analysis / Q000378:metabolism; D051381:Rats
D006017:Glycolipids; D009569:Nitric Oxide; D019344:Lactic Acid; D011493:Protein Kinase C; D005947:Glucose; D015232:Dinoprostone