The results of an in-vitro study showed that the secretion of TNF-α and NO was significantly suppressed by aqueous extract of Nigella sativa indicating that anti-inflammatory effects of the extract of this plant (Majdalawieh et al., 2010 ▶).A link between inflammation and bone homeostasis has been attributed to the effects of cytokines such as IL-1β, TNF- α, expressed in patients with RA and in the arthritic joints of rat with collagen-induced arthritis (Umar et al., 2012 ▶; Schett et al., 2008 ▶). Here, TNF is linked to rheumatoid arthritis.