RESUMO
The phytosterols, beta-sitosterol (BSS), and its glucoside (BSSG) enhance the in vitro proliferative response of T-cells stimulated by sub-optimal concentrations of phytohaemagglutinin (PHA) several fold at extremely low concentrations (femtogram level). A 100:1 (mass:mass) ratio of BSS:BSSG (termed essential sterolin formulation, ESF) showed higher stimulation than the individual sterols at the same concentration. In vivo activity of ESF was also demonstrated when volunteers ingested ESF for 4 weeks. Proliferation of their T-cells, stimulated maximally with PHA, was significantly enhanced (20-920%) when compared to baseline values. In vitro, ESF (1 microgram.ml) was able to significantly enhance the expression of CD25 and HLA-Dr activation antigens on T-cells and increased the secretion, into the medium, of IL-2 and gamma interferon. NK-cell activity was also increased by BSS and BSSG alone, but with EST a higher activity was always found at different effector:target ratios (100:1 12:1).
Assuntos
Sitosteroides/farmacologia , Linfócitos T/imunologia , Adjuvantes Imunológicos/farmacologia , Adulto , Antineoplásicos/farmacologia , Relação Dose-Resposta Imunológica , Combinação de Medicamentos , Feminino , Antígenos HLA-DR/fisiologia , Humanos , Interferon gama/metabolismo , Interleucina-2/metabolismo , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/fisiologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Linfócitos T/metabolismoRESUMO
The characterisation of two new thymol derivatives, found in the rootstock of CALLILEPIS LAUREOLA D C (Asteraceae), is reported together with that of a new ketol which was formed as a degradation product during the investigations.
