ABSTRACT
The estrous cycle disruptor effect of an ethanolic extract (EMATst) from Buddleja globosa leaves and standardized in its main component (verbascoside) was determined in rats after the subcutaneous administration of EMATst. Binding of EMATst and verbascoside to the estrogen receptor (ER) of EMATst and verbacoside was also measuredestablished. EMATst produced a significant alteration inof the estrous cycle only at the highest dose (10-5 M), which could be attributed to an antiestrogenic effect. The Bbinding of EMATst and verbascoside to the ER was competitive and occurred in concentrations 1000 times greater than that of 17beta-estradiol.
El efecto disruptor del ciclo estral de un extracto etanólico (EMATst) obtenido a partir de las hojas de Buddleja globosa y estandarizado en su componente mayoritario (verbascósido) fue determinado en ratas después de la administración subcutánea de EMATst. Se estableció además la unión al receptor estrogénico (RE) tanto de EMATst como de verbascósido. EMATst sólo a la dosis más alta (10-5M) produjo una alteración significativa del ciclo estral, lo que podría atribuirse a un efecto antiestrogénico. La unión al RE de EMATst y verbascósido se produjo a concentraciones 1000 veces mayor que el 17beta-estradiol y de forma competitiva.
Subject(s)
Animals , Rats , Buddleja/chemistry , Estrous Cycle , Plant Extracts/pharmacology , Phenols/pharmacology , Glucosides/pharmacology , Ethanol , Plant Leaves/chemistry , Rats, Sprague-Dawley , Receptors, EstrogenABSTRACT
Aim To study the phytoestrogenic effect and its mechanism of isopsoralen in estrogen receptor (ER) positive T47D and ER negative MDA-MB231 breast cancer cell line.Methods The proliferation rate and cell cycle distribution of T47D and MDA-MB231 cells influenced by isopsoralen were analyzed by MTT and flow cytometry assay respectively.PS2 mRNA level in T47D cells was quantified by Real-time RT-PCR assay.PS2 expression was measured by flow cytometry.Estrogen receptor antagonist ICI180,782 was employed as a tool.Results The proliferation rates and indexes of T47D cells treated with 1?10-6 mol?L-1 and 1?10-7 mol?L-1 isopsoralen were increased.These effects could be blocked by ICI182,780.Meanwhile,isopsoralen didn't show stimulative effects on proliferation rate of MDA-MB231 cells.Real-time RT-PCR and flow cytometry results showed that isopsoralen at 1?10-6 mol?L-1 and 1?10-7 mol?L-1 could induce elevation of pS2 mRNA and protein expression level in T47D cells.These effects could be partly blocked by ICI182,780.Conclusion Isopsoralen has phytoestrogenic effect and its effect is attained mainly via ER pathway.