Immunomodulatory potential of rhizome and seed extracts of Nelumbo nucifera Gaertn.

Abstract

Nelumbo nucifera Gaertn. (Nymphaeaceae) is a well-known aquatic plant which has been used for the treatment of several disorders including skin disease, cough, inflammation, fever and many other disorders. To explore the immunomodulatory activity of extract of rhizome (NNRE) and seed (NNSE) of the plant. The immunomodulatory activity of NNRE and NNSE was evaluated using various in vivo models including the total and differential leukocyte count (TLC and DLC), nitroblue-tetrazolium reduction (NBT) test, neutrophil adhesion test, phagocytic response and delayed type hypersensitivity (DTH) reaction. Sheep red blood cells (SRBC, 5 x 10(9)cells/ml) were used to immunize the animals. NNRE and NNSE at the doses of 100 and 300 mg/kg were administrated. The TLC and lymphocyte count increased significantly but the neutrophil count was decreased for NNRE and NNSE treated groups compared to the control. A dose-dependent potentiation of DTH reaction induced by SRBC was observed from the extracts. The percentage of neutrophil adhesion to the nylon fiber was increased in NNRE treated groups (63.22 and 62.91%) compared to the NNSE treated group (54.86 and 54.23%). A potential phagocytic response was seen on treatment of the extracts, and significant changes were observed in the formation of formazone crystals. This finding suggests that the extract of rhizome and seed Nelumbo nucifera stimulate defense system by modulating several immunological parameters.