ABSTRACT
The cytotoxic effects of seven constituents isolated from Duguetia glabriuscula were evaluated against Hep2 human larynx carcinoma cells. The cytotoxicity exhibited by beta-sitosterol was as strong as that of cis-platin. (+)-Alloaromadendran-10,14beta-diol caused inhibition of cellular growth with IC50 values lower than 25 microg/ml, a feature that was considered as revealing significant activity. Polycarpol showed borderline cytotoxicity, whereas the other compounds were inactive.
Subject(s)
Annonaceae/chemistry , Antineoplastic Agents, Phytogenic/toxicity , Sitosterols/toxicity , Cell Line, Tumor , Cisplatin/toxicity , Humans , Inhibitory Concentration 50 , Plant Bark/chemistry , Plant Extracts/chemistry , Plant Extracts/toxicity , Plant Leaves/chemistry , Polycyclic Aromatic Hydrocarbons/toxicity , Toxicity Tests/methodsABSTRACT
Physalis angulata is a solanaceae widely used in folk medicine in various tropical countries in the world. We have previously described that seco-steroids (physalins) purified from P. angulata are potent inhibitors of macrophage activation, blocking the production of pro-inflammatory cytokines and LPS-induced lethality. Herein we investigated the immunomodulatory activities of these substances in lymphocyte proliferation and cytokine production and in transplantation. The addition of physalins B, F or G to concanavalin A-activated splenocyte cultures induced a concentration-dependent inhibition of proliferation. Physalin B also inhibited IL-2 production by Con A-activated spleen cells. The addition of 2 mug/ml physalin B to mixed lymphocyte reaction (MLR) caused a 100% inhibition of proliferation. More importantly, treatment of mice with physalin B, F or G prevented the rejection of allogeneic heterotopic heart transplant. Our results demonstrate the suppressive activity of physalins B, F and G in lymphocyte function and indicate the potential use of physalins as immunosuppressive agents for treatments of pathologies in which inhibition of immune responses is desired.