The stimulation and inhibition of beta-2 adrenergic receptor on the inflammatory responses of ovary and immune system in the aged laying hens

Evolutionarily conserved mechanisms regulating stress-induced neutrophil redistribution in fish

Introduction

Stress may pose a serious challenge to immune homeostasis. Stress however also may prepare the immune system for challenges such as wounding or infection, which are likely to happen during a fight or flight stress response.

Methods

In common carp (Cyprinus carpio L.) we studied the stress-induced redistribution of neutrophils into circulation, and the expression of genes encoding CXC chemokines known to be involved in the regulation of neutrophil retention (CXCL12) and redistribution (CXCL8), and their receptors (CXCR4 and CXCR1-2, respectively) in blood leukocytes and in the fish hematopoietic organ - the head kidney. The potential involvement of CXC receptors and stress hormone receptors in stress-induced neutrophil redistribution was determined by an in vivo study with selective CXCR inhibitors and antagonists of the receptors involved in stress regulation: glucocorticoid/mineralocorticoid receptors (GRs/MRs), adrenergic receptors (ADRs) and the melanocortin 2 receptor (MC2R).

Results

The stress-induced increase of blood neutrophils was accompanied by a neutrophil decrease in the hematopoietic organs. This increase was cortisol-induced and GR-dependent. Moreover, stress upregulated the expression of genes encoding CXCL12 and CXCL8 chemokines, their receptors, and the receptor for granulocytes colony-stimulation factor (GCSFR) and matrix metalloproteinase 9 (MMP9). Blocking of the CXCR4 and CXCR1 and 2 receptors with selective inhibitors inhibited the stress-induced neutrophil redistribution and affected the expression of genes encoding CXC chemokines and CXCRs as well as GCSFR and MMP9.

Discussion

Our data demonstrate that acute stress leads to the mobilization of the immune system, characterized by neutrophilia. CXC chemokines and CXC receptors are involved in this stress-induced redistribution of neutrophils from the hematopoietic tissue into the peripheral blood. This phenomenon is directly regulated by interactions between cortisol and the GR/MR. Considering the pivotal importance of neutrophilic granulocytes in the first line of defense, this knowledge is important for aquaculture, but will also contribute to the mechanisms involved in the stress-induced perturbation in neutrophil redistribution as often observed in clinical practice.

Mechanisms of β-adrenergic receptors agonists in mediating pro and anti-apoptotic pathways in hyperglycemic Müller cells

BACKGROUND

The current study aimed to investigate the stimulatory effect of beta-adrenergic receptors (β-ARs) on brain derived neurotropic factor (BDNF) and cAMP response element binding protein (CREB).

METHODS

Human Müller cells were cultured in low and high glucose conditions. Cells were treated with xamoterol (selective agonist for β1-AR), salmeterol (selective agonist for β2-AR), isoproterenol (β-ARs agonist) and propranolol (β-ARs antagonist), at 20 µM concentration for 24 h. Western Blotting assay was performed for the gene expression analysis. DNA damage was evaluated by TUNEL assay. DCFH-DA assay was used to check the level of reactive oxygen species (ROS). Cytochrome C release was measured by ELISA.

RESULTS

Xamoterol, salmeterol and isoproterenol showed no effect on Caspase-8 but it reduced the apoptosis and increased the expression of BDNF in Müller cells. A significant change in the expression of caspase-3 was observed in cells treated with xamoterol and salmeterol as compared to isoproterenol. Xamoterol, salmeterol and isoproterenol significantly decreased the reactive oxygen species (ROS) when treated for 24 hours. Glucose-induced cytochrome c release was disrupted in Müller cells.

CONCLUSION

β-ARs, stimulated by agonist play a protective role in hyperglycemic Müller cells, with the suppression of glucose-induced caspase-3 and cytochrome c release. B-Ars may directly mediate the gene expression of BDNF.

Dietary naringin supplementation on laying performance and antioxidant capacity of Three-Yellow breeder hens during the late laying period

In this study, the effects of 3 graded dietary levels (0.1%, 0.2%, and 0.4%) of naringin were studied in Three-Yellow breeder hens during the late laying period (55–62 wk). A total of 480 Three-Yellow breeder hens (54-wk-old) were randomly divided into 4 groups (6 replicates of 20 hens): basal diet group (C), and basal diets supplemented with 0.1%, 0.2%, and 0.4% of naringin (N1, N2, and N3), respectively. Results showed that dietary supplementation with 0.1%, 0.2%, and 0.4% of naringin for 8 wk increased the laying rate and egg mass, enhanced egg yolk color, and decreased the feed egg ratio (P < 0.05). Meanwhile, compared with hens in C group, there were more preovulatory follicles and higher ovarian index as well as an enhanced ovarian somatic cell proliferation in hens of N2 and N3 groups (P < 0.05). With 0.2% and 0.4% naringin, glutathione concentration, the activity of catalase and total superoxide dismutase, and the total antioxidant capacity of ovarian tissues and serum increased (P < 0.05), while the contents of malondialdehyde and hydrogen peroxide decreased (P < 0.05). Moreover, compared to C group, the transcription levels of antioxidant genes in ovarian tissues increased in hens from N2 and N3 groups (P < 0.05). In conclusion, supplementation with 0.2% and 0.4% naringin both could improve the laying rate, ovarian and serum antioxidant capacity of Three-Yellow breeder hens during the late laying period.

Transcriptome comparative analysis of ovarian follicles reveals the key genes and signaling pathways implicated in hen egg production

Background

Ovarian follicle development plays an important role in determination of poultry egg production. The follicles at the various developmental stages possess their own distinct molecular genetic characteristics and have different biological roles in chicken ovary development and function. In the each stage, several genes of follicle-specific expression and biological pathways are involved in the vary-sized follicular development and physiological events. Identification of the pivotal genes and signaling pathways that control the follicular development is helpful for understanding their exact regulatory functions and molecular mechanisms underlying egg-laying traits of laying hens.

Results

The comparative mRNA transcriptomic analysis of ovarian follicles at three key developmental stages including slow growing white follicles (GWF), small yellow follicles (SYF) of recruitment into the hierarchy, and differentiated large yellow follicles (LYF), was accomplished in the layers with lower and higher egg production. Totally, 137, 447, and 229 of up-regulated differentially expressed genes (DEGs), and 99, 97, and 157 of down-regulated DEGs in the GWF, SYF and LYF follicles, including VIPR1, VIPR2, ADRB2, and HSD17B1 were identified, respectively. Moreover, NDUFAB1 and GABRA1 genes, two most promising candidates potentially associated with egg-laying performance were screened out from the 13 co-expressed DEGs in the GWF, SYF and LYF samples. We further investigated the biological effects of NDUFAB1 and GABRA1 on ovarian follicular development and found that NDUFAB1 promotes follicle development by stimulating granulosa cell (GC) proliferation and decreasing cell apoptosis, increases the expression of CCND1 and BCL-2 but attenuates the expression of caspase-3, and facilitates steroidogenesis by enhancing the expression of STAR and CYP11A1. In contrast, GABRA1 inhibits GC proliferation and stimulates cell apoptosis, decreases the expression of CCND1, BCL-2, STAR, and CYP11A1 but elevates the expression of caspase-3. Furthermore, the three crucial signaling pathways such as PPAR signaling pathway, cAMP signaling pathway and neuroactive ligand-receptor interaction were significantly enriched, which may play essential roles in ovarian follicle growth, differentiation, follicle selection, and maturation.

Conclusions

The current study provided new molecular data for insight into the regulatory mechanism underlying ovarian follicle development associated with egg production in chicken.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-08213-w.