Immunomodulatory effects of agents of plant origin

The immunomodulatory properties of amla (Emblica officinalis) and shankhpushpi (Evolvulus alsinoides) were evaluated in adjuvant induced arthritic (AIA) rat model. Injecting Complete Freund's Adjuvant (CFA) in right hind paw of the animals induced inflammation. The crude extracts of both the herbs were administered intraperitonially following a repeated treatment profile. The anti-inflammatory response of both the extracts was determined by lymphocyte proliferation activity and histopathological severity of synovial hyperplasia. Both the extracts showed a marked reduction in inflammation and edema. At cellular level immunosuppression occurred during the early phase of the disease. There was mild, synovial hyperplasia and infiltration of few mononuclear cells in amla or shankhpushpi treated animals. The induction of nitric oxide synthase (NOS) was significantly decreased in treated animals as compared to controls. These observations suggest that both the herbal extracts caused immunosuppression in AIA rats, indicating that they may provide an alternative approach to the treatment of arthritis. (C) 2003 Editions scientifiques et medicales Elsevier SAS. All rights reserved.