Abstract
Background: Decalepis hamiltonii Wight and Arn (Asclepiadaceae) commonly known as 'nannari' is an Indian medicinal plant which is having ethno-medicinal uses as antioxidant, tonic and blood purifier. It is used in many Ayurvedic preparations like Drakshadi churna (general vitalizer), Shatavari rasayana (adaptogenic), and Yeshtimadhu taila (mild analgesic, rheumatism). Aim of the present study is to evaluate the immunomodulatory activity of D. hamiltoni roots aqueous extract in rodents. Methods: D. hamiltoni aqueous extract (DHAE) was prepared by cold maceration. Two doses of DHAE (100 and 200 mg/kg, per os) were used to evaluate immunomodulatory activity in vivo and ex vivo through assessments of hemagglutination antibody titers, hematological profiles (Hb, WBC, RBC), delayed-type hypersensitivity (DTH), neutrophil adhesion, and carbon clearance. Results: DHAE at both dose levels evoked significant dose-dependent increases in antibody titers and DTH reactions induced by SRBC, and potentiated percentage neutrophil adhesion to nylon fibers as well as phagocytosis of carbon particles in situ. Conclusion: The evidence collected here lends support to traditional claims behind the use of D. hamiltonii for medicinal purposes. The study also affirmed that DHAE imparts immunomodulatory activity. The DHAE not only potentiated non-specific immune responses, but also was effective in improving immune responses in cyclophos-phamide-immunosuppressed hosts. The results here indicate that D. hamiltonii root extracts stimulates both cellular and humoral immune responses.