Steroid sex hormones, such as estradiol-17β （E2） and testosterone （T）, are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gon...Steroid sex hormones, such as estradiol-17β （E2） and testosterone （T）, are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichtbys olivaceus using histology and radioimmunoassay （RIA）. Flounder larvae were divided into five groups （G0~G4）, and fed with 0 （control）, 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching （dph）. Fish growth in the G1 and G2 groups was not significantly different from that of the control group （P〉0.05）, while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P olivaceus.展开更多
OBJECTIVE:To investigate the mechanism underlying the anticancer effect of Artemisia species through the inhibition of cell growth and induction of apoptosis in breast carcinoma cells.METHODS:To evaluate the anticance...OBJECTIVE:To investigate the mechanism underlying the anticancer effect of Artemisia species through the inhibition of cell growth and induction of apoptosis in breast carcinoma cells.METHODS:To evaluate the anticancer activity of methanol extracts of eight Artemisia species(Artemisia stolonifera,Artemisia selengensis,Artemisia japonica,Artemisia Montana,Artemisia capillaris,Artemisia sylvatica,Artemisia keiskeana,and Artemisia scoparia),we first investigated the proliferation of estrogen receptor(ER)-positive MCF-7breast carcinoma cells exposed to 5 or 200 g/mL for72 h.Apoptosis induction was assessed by an Annexin V binding assay in cells exposed to extracts at a high concentration(200 g/mL).To verify the mechanism of apoptosis,ER expression and its related signaling was investigated using an immunoblot assay under the same conditions.RESULTS:MCF-7 cells showed the strongest antiproliferative response to the tested extracts.Howev-er,a biphasic effect was observed:the extracts inhibited proliferation at high concentrations whereas they stimulated it at low ones.ER expression was similarly modulated by the extracts.However,all of the extracts induced apoptosis at a high concentration(200 g/mL).Compared to the control level,exposure to the extracts resulted in a remarkable increase in the shift of cell populations.CONCLUSION:The present study suggests that the tested Artemisia species exerted their anticancer effects through the induction of apoptosis via an ER-related pathway.展开更多
基金Supported by the National Natural Science Foundation of China(No.30571445)the National High Technology Research and Development Program of China(863 Program)(No.2006AA10A404)the Earmarked Fund for Modern Agro-Industry Technology Research System,China(No.nycytx-50)
文摘Steroid sex hormones, such as estradiol-17β （E2） and testosterone （T）, are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichtbys olivaceus using histology and radioimmunoassay （RIA）. Flounder larvae were divided into five groups （G0~G4）, and fed with 0 （control）, 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching （dph）. Fish growth in the G1 and G2 groups was not significantly different from that of the control group （P〉0.05）, while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P olivaceus.
基金Supported by Priority Research Centers Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(NRF-2009-0094017 and NRF-2011-0017017)
文摘OBJECTIVE:To investigate the mechanism underlying the anticancer effect of Artemisia species through the inhibition of cell growth and induction of apoptosis in breast carcinoma cells.METHODS:To evaluate the anticancer activity of methanol extracts of eight Artemisia species(Artemisia stolonifera,Artemisia selengensis,Artemisia japonica,Artemisia Montana,Artemisia capillaris,Artemisia sylvatica,Artemisia keiskeana,and Artemisia scoparia),we first investigated the proliferation of estrogen receptor(ER)-positive MCF-7breast carcinoma cells exposed to 5 or 200 g/mL for72 h.Apoptosis induction was assessed by an Annexin V binding assay in cells exposed to extracts at a high concentration(200 g/mL).To verify the mechanism of apoptosis,ER expression and its related signaling was investigated using an immunoblot assay under the same conditions.RESULTS:MCF-7 cells showed the strongest antiproliferative response to the tested extracts.Howev-er,a biphasic effect was observed:the extracts inhibited proliferation at high concentrations whereas they stimulated it at low ones.ER expression was similarly modulated by the extracts.However,all of the extracts induced apoptosis at a high concentration(200 g/mL).Compared to the control level,exposure to the extracts resulted in a remarkable increase in the shift of cell populations.CONCLUSION:The present study suggests that the tested Artemisia species exerted their anticancer effects through the induction of apoptosis via an ER-related pathway.
