Biochemically active substances from microorganisms IV. Establishment of several in vitro anti-inflammatory probes applicable to microbial broths and the effects of non-steroidal anti-inflammatory drugs and antibiotics on them.

Abstract

Assay systems (4), i.e., membrane stabilization, inhibition of protein denaturation, and inhibition of collagen- and ADP-induced bovine platelet aggregation, were examined for possible use as in vitro antiinflammatory screening probes applicable to microbial metabolites. All these systems were simple and reasonably selective for known platelet antiaggregants or nonsteroidal antiinflammatory agents. As regards sensitivity, detection should be possible at levels of several to several hundred .mu.g/ml for an indomethacin class substance existing in the broth; such concentrations are attainable in the broth in the case of useful antibiotic production. Each system was hardly disturbed by medium components in the broth and the procedures were successfully applied to actinomycetes cultures. Upon examination of typical nonsteroidal antiinflammatory drugs to determine their effects on these systems, it was found that they could be classified into 4 distinct types in terms of their mode of action. The correlation of these effects with results in several in vivo models is discussed. The effects of various antibiotics including several types of ionophores on these probes were thoroughly studied.