Mycoplasma fermentans - Induced inflammatory response of astrocytes: Selective modulation by aminoguanidine, thalidomide, pentoxifylline and IL-10

Exposure of primary rat glial cells, mostly astrocytes, to heat- inactivated Mycoplasma fermentans triggers the production of tumor necrosis factor a (TNFα) nitric oxide (NO) and prostaglandin E₂ (PGE₂). To attenuate the production of these proinflammatory mediators, four agents: aminoguanidine, pentoxifylline, thalidomide and IL-10 were added to astrocyte cultures. Aminoguanidine (1 and 3 mM), an inhibitor of inducible nitric oxide synthase (iNOS), suppressed the production of the three mediators. TNFα was the most sensitive to thalidomide, showing dose-response inhibition at concentrations of 20 μg/ml, 50 μg/ml and 250 μg/ml. PGE₂ was affected only by concentrations of 50 μg/ml and 250 μg/ml, whereas NO responded solely to the highest amount of this inhibitor. The cytokine IL-10, at 10 U and 50 U, inhibited only TNFα production. Our results imply that selective suppression of proinflammatory mediators by various agents may prove feasible for amelioration of central nervous system inflammatory diseases.