Effects of the Chinese traditional medicines "mao-bushi-saishin-to" and "yokuinin" on the antimycobacterial activity of murine macrophages against Mycobacterium avium complex infection

Abstract

We previously examined the effects of two Chinese traditional medicines "Mao-Bushi-Saishin-To" (MBST) and "Yokuinin", on the therapeutic efficacies of a benzoxazinorifamycin, KRM-1648, against Mycobacterium avium complex (MAC) infection induced in mice. MBST but not Yokuinin potentiated the therapeutic activity of KRM-1648 against MAC infection. In the present study, we examined the effects of these traditional medicines on some M phi cell functions. First, MBST significantly potentiated M phi anti-MAC antimicrobial activity, while Yokuinin did so to a much lesser extent. Secondly, MBST and Yokuinin each strongly inhibited production of nitric oxide (NO) in MAC-infected M phi s. Thirdly, treatment of M phi s with MBST or Yokuinin caused reductions in the accumulation of IL-10 in culture fluids by MAC-infected M phi s during the first 2-days cultivation. On the other hand, in the separate experiment, treatment of M phi s with these drugs caused no significant change in the accumulation of TGF-beta by MAC-infected M phi s at day 7. These findings suggest that these Chinese traditional medicines, particularly MBST, potentiate M phi anti-MAC antimicrobial activity, however, NO do not appear to be crucial effectors in the anti-MAC activity of MBST- or Yokuinin-treated M phi s. Moreover, MBST- and Yokuinin-mediated down-regulation of the production of IL-10 in MAC-infected M phi s may be related to their potentiating effects on M phi anti-MAC activity.