Antioxidant effect of a phytoestrogen equol on cultured muscle cells of embryonic broilers.

Previous studies have shown that the in ovo injection of equol can markedly improve the water-holding capacity of muscles of broilers chickens at 7 wk of age through promotion of the antioxidant status. We aimed to investigate directly the antioxidant effects of equol on muscle cells in broilers. Muscle cells were separated from leg muscle of embryos on the 11th day of incubation and treated with equol and H(2)O(2), either alone or together.

Effect of glucocorticoids pretreatment on steroidogenic capacity of adrenocortical cells isolated from Meishan piglets.

The present in vitro experiment was designed to test whether 48 h of pretreatment with glucocorticoids, cortisol, or dexamethasone (DEX), would affect basal and corticotrophin (ACTH) stimulated (24 h) cortisol secretion from primary cultures of pig adrenocortical cells. Cells were divided into six groups: control pretreatment with or without ACTH challenge, cortisol pretreatment with or without ACTH challenge, and DEX pretreatment with or without ACTH. The culture medium and cells were collected at the end of treatment.

Dual effects of daidzein on chicken hepatic vitellogenin II expression and estrogen receptor-mediated transactivation in vitro.

Two in vitro systems were employed to delineate the estrogenic activity of daidzein (Da), alone or in combination with high or low concentrations of estrogen in two cell types possessing different estrogen-receptor (ER) isoforms, ERalpha and/or ERbeta: (1) vitellogenin II (VTG), the egg yolk precursor protein and the endpoint biomarker for estrogenicity, in chicken primary hepatocytes, and (2) CHO-K1 cells transiently co-transfected with ERalpha or ERbeta and estrogen-response elements (ERE) linked to a luciferase reporter gene. Da (100 microM) alone induced VTG mRNA expression in chicken hepatocytes, albeit with much less potency compared to estradiol (E(2)). Da exhibited different effects in the presence of 1 microM and 10 microM E(2).

[Isolation and expression of novel expressed sequence tags (ESTs) from ovarian follicles of Shaoxing ducks].

Three expressed sequence tags ( ESTs), SXDF0201 (271 bp), SXDF0202 (200 bp) and SXDF0203 (173 bp), were isolated from ovarian follicles of Shaoxing ducks by using silver staining mRNA differential display. GenBank/BLAST analysis revealed that SXDF0201 was not homologous to any of the published sequences from all species, indicating that it was a novel EST and was then registered in GenBank (GenBank Accession No.: CB072629), while SXDF0202 and SXDF0203 were found to be highly homologous to seven known chicken ESTs and chicken mRNA for gizzard smooth muscle myosin heavy chain.

[Expression of mRNAs for GHR, IGF-IR, FSHR and LHR in granulosa and theca layers of ovarian follicles of Shaoxing ducks].

Expression of genes encoding growth hormone receptor (GHR), type I insulin-like growth factor receptor (IGF-IR), follicle-stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) was measured in granulosa and theca layers of the largest (F1), third largest (F3), fifth largest (F5) preovulatory follicles and large white follicles (LWF) in the ovary of Shaoxing ducks, with relative quantitative reverse transcription-polymerase chain reaction (RT-PCR) using beta-actin as an internal standard. The results showed that GHR mRNA was more abundant in theca layer than in granulosa layer in all the follicles investigated, in theca layer, the LWF follicle expressed highest the level of GHR mRNA, while no differences in granulosa layer were observed among follicles at different stages of development. In contrast, the expression of IGF-IR mRNA in theca layer was evidently lower than that in granulosa layer, but no significant changes were found among different stages of follicles in either layers, except that LWF trended to express higher IGF-IR mRNA in the theca layer compared to other preovulatory follicles.