Inhibition of Propionibacterium acnes-induced mediators of inflammation by Indian herbs

Propionibacterium acnes, an anaerobic pathogen, plays an important role in the pathogenesis of acne by inducing certain inflammatory mediators. These mediators include reactive oxygen species (ROS) and pro-inflammatory cytokines. In the present study, ROS, interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-alpha) were used as the major criteria for the evaluation of anti-inflammatory activity. To prove the anti-inflammatory effects of herbs, polymorphonuclear leukocytes (PMNL) and monocytes were treated with culture supernatant of P acnes in the presence or absence of herbs. It was found that Rubia cordifolia, Curcuma longa, Hemidesmus indicus, and Azadirachta indica caused a statistically significant suppression of ROS from PMNL. Sphaeranthus indicus caused a smaller, still significant suppression of ROS. Aloe vera had no effect on ROS production. In the case of proinflammatory cytokine-induced monocytes, maximum suppression was shown by Azadirachta indica and Sphaeranthus indicus, followed by Hemidesmus indicus, Rubia cordifolia, and Curcuma longa. Aloe vera showed insignificant inhibitory activity. Thus, these herbs shows anti-inflammatory activity by suppressing the capacity of P acnes-induced ROS and pro-inflammatory cytokines, the two important inflammatory mediators in acne pathogenesis.