Tinospora tuberculata suppresses nitric oxide synthesis in mouse macrophages.

We have obtained evidence that co-incubation of thioglycollate-elicited peritoneal macrophages with an aqueous extract of Tinospora tuberculata inhibits lipopolysaccharide-stimulated excessive production of nitric oxide (NO) in vitro. This effect is concentration-dependent and appears to involve suppression of both inducible nitric oxide synthase (iNOS) activity and NADPH-diaphorase activity, thus altering NO production. As NO is one of the critical mediators in various disorders and iNOS inhibitors may have therapeutic potential, these results may explain some aspects of the multifunctional properties of Tinospora tuberculata, which has been used in various folk remedies in southeast Asia and China.