In Southern Africa, the medicinal plant Warburgia salutaris is commonly used for the treatment of inflammatory and other diseases. The methanol extracts of W. salutaris were investigated with regard to a) production of proinflammatory cytokines tumor necrosis factor-α, interleukin-1β, and interferon-γ; b) activation of the transcription factor nuclear factor kappa B; and c) induction of deoxyribonucleic acid (DNA) damage and lipid peroxidation in the presence of crystalline silica particles. Due to its antioxidant properties, extracts of W. salutaris showed protective effects against crystalline silica-induced inflammatory cytokine expression, activation of nuclear transcription factor-κB, DNA strand breakage, and lipid peroxidation. Hence, W. salutaris may be a potential therapeutic agent against the fibrogenic and carcinogenic effects of crystalline silica.
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