Expression characteristics and regulatory mechanism of Apela gene in liver of chicken (Gallus gallus)

The Diverse Roles of 17β-Estradiol in Non-Gonadal Tissues and Its Consequential Impact on Reproduction in Laying and Broiler Breeder Hens

Estradiol-17β (E2) has long been studied as the primary estrogen involved in sexual maturation of hens. Due to the oviparous nature of avian species, ovarian production of E2 has been indicated as the key steroid responsible for activating the formation of the eggshell and internal egg components in hens. This involves the integration and coordination between ovarian follicular development, liver metabolism and bone physiology to produce the follicle, yolk and albumen, and shell, respectively. However, the ability of E2 to be synthesized by non-gonadal tissues such as the skin, heart, muscle, liver, brain, adipose tissue, pancreas, and adrenal glands demonstrates the capability of this hormone to influence a variety of physiological processes. Thus, in this review, we intend to re-establish the role of E2 within these tissues and identify direct and indirect integration between the control of reproduction, metabolism, and bone physiology. Specifically, the sources of E2 and its activity in these tissues via the estrogen receptors (ERα, ERβ, GPR30) is described. This is followed by an update on the role of E2 during sexual differentiation of the embryo and maturation of the hen. We then also consider the implications of the recent discovery of additional E2 elevations during an extended laying cycle. Next, the specific roles of E2 in yolk formation and skeletal development are outlined. Finally, the consequences of altered E2 production in mature hens and the associated disorders are discussed. While these areas of study have been previously independently considered, this comprehensive review intends to highlight the critical roles played by E2 to alter and coordinate physiological processes in preparation for the laying cycle.

Growth performance and meat quality from broiler chickens reared with zeolite and halloysite in feed and straw pellet

The study's aim was to analyze the effects of different levels of halloysite (H) and zeolite (Z) in feed and pellets on the growth and meat quality in chickens; 500 Ross 308 broilers were assigned to five groups (1 g, control; 2-5 g, experimental). In Groups 2-5, different proportions of Z and H in feed (25:75 ratio; 0.5% to 2%) and pellet in kg/m² (2, 0.650H; 3, 0.325H and 0.325Z; 4, 0.650Z; 5, 0.160H and 0.490Z) were used. Body weight was higher than 1 in all experimental groups, and carcass weight was higher, except for Group 2. The feed consumption was lower in Groups 3 and 5 than in Group 4. The breast muscle weight was higher in Group 3 than in the control group. In Groups 2, 3, and 5, the water holding capacity in the breast muscles was better than in Group 4 and in the leg muscles in Groups 3 and 4 than in Groups 1 and 5. Most of the tested characteristics indicate a beneficial effect of aluminosilicates in feed and litter on the growth and quality of meat.

Regulation of Apelin-13 on Bcl-2 and Caspase-3 and Its Effects on Adipocyte Apoptosis

OBJECTIVE

The effects of apelin-13 on the expression of Bcl-2 and caspase-3 factors and the apoptosis of adipocytes were studied at the cellular and animal levels.

METHODS

3T3-L1 preadipocytes were cultured and grouped. The third-generation cells were added to the control DMSO solvent and amidation-modified apelin-13. The expression of Bcl-2 and caspase-3 were detected. The cell growth viability and cell apoptosis were detected. DOI model rats were established. The effects of apelin-13 on DOI rat biochemical indicators, the expression of Bcl-2, caspase-3, and cell apoptosis were investigated by injecting amidation-modified apelin-13 through the tail vein.

RESULT

In in vitro experiments, amidation-modified apelin-13 can significantly reduce the growth viability of adipocytes and the expression of Bcl-2, increase the expression of caspase-3, and promote the apoptosis of adipocytes. Animal experiments also show that apelin-13 modified by amidation can adjust the abnormal biochemical indicators of DOI rats, decrease the expression of Bcl-2 in adipose tissue, increase the expression of caspase-3, and promote the apoptosis of adipocytes.

CONCLUSION

Amidation of apelin-13 can promote fat cell apoptosis and reduce the incidence of obesity. The mechanism may be accomplished by inhibiting Bcl-2 and caspase-3 factors. This study helps us understand the effect of apelin-13 on fat cell apoptosis and hopes to provide a basis for the development of antiobesity drugs.

Roles of Estrogens in the Healthy and Diseased Oviparous Vertebrate Liver

The liver is a vital organ that sustains multiple functions beneficial for the whole organism. It is sexually dimorphic, presenting sex-biased gene expression with implications for the phenotypic differences between males and females. Estrogens are involved in this sex dimorphism and their actions in the liver of several reptiles, fishes, amphibians, and birds are discussed. The liver participates in reproduction by producing vitellogenins (yolk proteins) and eggshell proteins under the control of estrogens that act via two types of receptors active either mainly in the cell nucleus (ESR) or the cell membrane (GPER1). Estrogens also control hepatic lipid and lipoprotein metabolisms, with a triglyceride carrier role for VLDL from the liver to the ovaries during oogenesis. Moreover, the activation of the vitellogenin genes is used as a robust biomarker for exposure to xenoestrogens. In the context of liver diseases, high plasma estrogen levels are observed in fatty liver hemorrhagic syndrome (FLHS) in chicken implicating estrogens in the disease progression. Fishes are also used to investigate liver diseases, including models generated by mutation and transgenesis. In conclusion, studies on the roles of estrogens in the non-mammalian oviparous vertebrate liver have contributed enormously to unveil hormone-dependent physiological and physiopathological processes.