Proteins derived from in vitro culture of the callus and roots of Calotropis procera ameliorate acute inflammation in the rat paw

The callus and roots developed from the hypocotyl and cotyledon explants of the germinating seeds of Calotropis procera were grown in culture, and the proteins isolated from them (CP and RP) were evaluated for their efficacy in inhibiting edema formation induced by sub-plantar injection of carrageenan in the hind paw of rat. Intravenous administration of both CP and RP 30 min before inducing inflammation produced a dose-dependent inhibition of edema formation at 1 and 5 mg/kg doses. The extents of inhibition with these proteins ranged between 40 and 70 % at the doses included while the anti-inflammatory drug diclofenac produced 50 to 60 % inhibition at 5 mg/kg dose. The inhibitory effect with these proteins was accompanied by a dose-dependent reduction in the tissue levels of inflammatory mediators, tumor necrosis factor alpha (TNF-α) and prostaglandin E2 (PGE2), and oxidative stress markers namely glutathione and thiobarbituric acid-reactive substances and maintenance of tissue architecture. The present study shows that the proteins isolated from the differentiated and undifferentiated tissues derived from the germinating seeds have therapeutic application in the treatment of inflammatory conditions, and these tissues could be used as an alternative source to minimize variability of plant-derived formulations.