Melatonin regulates chicken granulosa cell proliferation and apoptosis by activating the mTOR signaling pathway via its receptors

Melatonin in animal husbandry: functions and applications

Melatonin (N-acetyl-5-methoxytryptamine) is an essential small molecule with diverse biological functions. It plays several key roles, including regulating the secretion of reproductive hormones and the reproductive cycle, enhancing the functionality of reproductive organs, improving the quality of sperm and eggs, and mitigating oxidative stress in the reproductive system. Melatonin effectively inhibits and scavenges excess free radicals while activating the antioxidant enzyme system and reduces the production of inflammatory factors and alleviates tissue damage caused by inflammation by regulating inflammatory pathways. Additionally, melatonin contributes to repairing the intestinal barrier and regulating the gut microbiota, thereby reducing bacterial and toxin permeation. The use of melatonin as an endogenous hormone in animal husbandry has garnered considerable attention because of its positive effects on animal production performance, reproductive outcomes, stress adaptation, disease treatment, and environmental sustainability. This review explores the characteristics and biological functions of melatonin, along with its current applications in animal production. Our findings may serve as a reference for the use of melatonin in animal farming and future developmental directions.

CircRAB11A act as miR-24-5p sponge promotes proliferation and resists apoptosis of chicken granulosa cell via EGFR/ERK1/2 and RAB11A/ PI3K/AKT pathways

Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs that have been implicated in mediating granulosa cell (GC) proliferation and apoptosis. CircRAB11A was found to have a significantly higher expression in normal follicles compared to atrophic follicles. In this study, we determined that the knockdown of circRAB11A resulted in the inhibition of proliferation and promotion of apoptosis in GCs of chicken. Moreover, circRAB11A was found to act as a sponge for miR-24-5p, both member RAS oncogene family (RAB11A) and epidermal growth factor receptor (EGFR) were revealed to be targets of miR-24-5p through a dual-luciferase reporter assay. RAB11A or EGFR promoted proliferation and suppressed apoptosis in GCs through the phosphatidylinositol-kinase (PI3K)/AKT or extracellular signal-regulated kinase (ERK)1/2 pathway. These findings suggest that circRAB11A may function as a competing endogenous RNA (ceRNA) by targeting the miR-24-5p/RAB11A and miR-24-5p/EGFR axes and activating the ERK1/2 and PI3K/AKT pathways, offering a potential avenue for exploring the mechanism of follicle development.

Integrating genomics and transcriptomics to identify candidate genes for high-altitude adaptation and egg production in Nixi chicken

1. This study combined genome-wide selection signal analysis with RNA-sequencing to identify candidate genes associated with high altitude adaptation and egg production performance in Nixi chickens (NXC).2. Based on the whole-genome data from 20 NXC (♂:10; ♀:10), the population selection signal was analysed by sliding window analysis. The selected genes were screened by combination with the population differentiation statistic (FST). The sequence diversity statistic (θπ). RNA-seq was performed on the ovarian tissues of NXC (n = 6) and Lohmann laying hens (n = 6) to analyse the differentially expressed genes (DEGs) between the two groups. The functional enrichment analysis of the selected genes and differentially expressed genes was performed.3. There were 742 genes under strong positive selection and 509 differentially expressed genes screened in NXC. Integrated analysis of the genome and transcriptome revealing 26 overlapping genes. The candidate genes for adaptation to a high-altitude environment, as well as for egg production, disease resistance, vision and pigmentation in NXC were preliminarily screened.4. The results provided theoretical guidance for further research on the genetic resource protection and utilisation of NXC.

Huayu Qutan Recipe promotes lipophagy and cholesterol efflux through the mTORC1/TFEB/ABCA1-SCARB1 signal axis

This study aims to investigate the mechanism of the anti-atherosclerosis effect of Huayu Qutan Recipe (HYQT) on the inhibition of foam cell formation. In vivo, the mice were randomly divided into three groups: CTRL group, MOD group and HYQT group. The HYQT group received HYQT oral administration twice a day (20.54 g/kg/d), and the plaque formation in ApoE-/- mice was observed using haematoxylin-eosin (HE) staining and oil red O (ORO) staining. The co-localization of aortic macrophages and lipid droplets (LDs) was examined using fluorescent labelling of CD11b and BODIPY fluorescence probe. In vitro, RAW 264.7 cells were exposed to 50 μg/mL ox-LDL for 48 h and then treated with HYQT for 24 h. The accumulation of LDs was evaluated using ORO and BODIPY. Cell viability was assessed using the CCK-8 assay. The co-localization of LC3b and BODIPY was detected via immunofluorescence and fluorescence probe. LysoTracker Red and BODIPY 493/503 were used as markers for lysosomes and LDs, respectively. Autophagosome formation were observed via transmission electron microscopy. The levels of LC3A/B II/LC3A/B I, p-mTOR/mTOR, p-4EBP1/4EBP1, p-P70S6K/P70S6K and TFEB protein level were examined via western blotting, while SQSTM1/p62, Beclin1, ABCA1, ABCG1 and SCARB1 were examined via qRT-PCR and western blotting. The nuclear translocation of TFEB was detected using immunofluorescence. The components of HYQT medicated serum were determined using Q-Orbitrap high-resolution MS analysis. Molecular docking was employed to identify the components of HYQT medicated serum responsible for the mTOR signalling pathway. The mechanism of taurine was illustrated. HYQT has a remarkable effect on atherosclerotic plaque formation and blood lipid level in ApoE-/- mice. HYQT decreased the co-localization of CD11b and BODIPY. HYQT (10% medicated serum) reduced the LDs accumulation in RAW 264.7 cells. HYQT and RAPA (rapamycin, a mTOR inhibitor) could promote cholesterol efflux, while chloroquine (CQ, an autophagy inhibitor) weakened the effect of HYQT. Moreover, MHY1485 (a mTOR agonist) also mitigated the effects of HYQT by reduced cholesterol efflux. qRT-PCR and WB results suggested that HYQT improved the expression of the proteins ABCA1, ABCG1 and SCARB1.HYQT regulates ABCA1 and SCARB1 protein depending on the mTORC1/TFEB signalling pathway. However, the activation of ABCG1 does not depend on this pathway. Q-Orbitrap high-resolution MS analysis results demonstrated that seven core compounds have good binding ability to the mTOR protein. Taurine may play an important role in the mechanism regulation. HYQT may reduce cardiovascular risk by promoting cholesterol efflux and degrading macrophage-derived foam cell formation. It has been observed that HYQT and ox-LDL regulate lipophagy through the mTOR/TFEB signalling pathway, rather than the mTOR/4EBP1/P70S6K pathway. Additionally, HYQT is found to regulate cholesterol efflux through the mTORC1/TFEB/ABCA1-SCARB1 signal axis, while taurine plays a significant role in lipophagy.

Copper exposure induces ovarian granulosa cell apoptosis by activating the caspase-dependent apoptosis signaling pathway and corresponding changes in microRNA patterns

Environmental copper (Cu) contamination is a complex worldwide public health problem. However, information on the effects of Cu pollution on human reproduction is limited. Although our previous studies have indicated that Cu exposure disrupts ovarian folliculogenesis, the underlying mechanism needs to be further explored. In this study, human luteinized ovarian granulosa cells and a rat animal model were used to investigate whether Cu exposure affects ovarian follicle development by inducing apoptosis and to elucidate the possible mechanisms. The results showed that Cu exposure from weaning to sexual maturity significantly decreased the proportion of preantral follicles but increased the proportion of atretic follicles (P < 0.05). In addition, 6 mg/kg Cu increased the proportion of antral follicles, while 12 and 25 mg/kg Cu decreased it (P < 0.05). We also found that 6 mg/kg Cu exposure inhibited apoptosis of ovarian granulosa cells, while 12 and 25 mg/kg Cu promoted apoptosis (P < 0.05). Experiments on primary human luteinized ovarian granulosa cells suggested that higher levels of Cu exposure induced a significant increase in the mRNA levels of Bcl2 Bax , Fas, Caspase8, and Caspase3 (P < 0.05), and the protein levels of BAX, BCL2, CASPASE3, CASPASE8, CLE-CASPASE3, CLE-CASPASE8 and BAX/BCL2 were also increased (P < 0.05). miRNA chip analyses identified a total of 95 upregulated and 10 downregulated miRNAs in human luteinized granulosa cells exposed to Cu. Hsa-miR-19b-3p, hsa-miR-19a-3p, miR-548ar-3p, hsa-miR-652-5p, and hsa-miR-29b-5p were decreased after Cu exposure (P < 0.05). Additionally, the level of hsa-miR-144-5p was increased (P < 0.05). Together, our results reveal that Cu exposure induces abnormal ovarian folliculogenesis by inducing ovarian granulosa cell apoptosis, which is triggered by the caspase-dependent apoptosis signaling pathway, and that miRNAs may be involved in this process.

The Hippo signaling pathway contributes to the 2,5-Hexadion-induced apoptosis of ovarian granulosa cells

Although n-hexane can induce ovarian damage by inducing ovarian granulosa cell (GC) apoptosis, the mechanism underlying this induction of apoptosis has not been fully elucidated. In this study, rat ovarian GCs were exposed to different concentrations of 2,5-hexanedione (2,5-HD) (the main metabolite of n-hexane) in vitro to observe apoptosis, and the mechanism was further explored via mRNA microarray analysis. Hoechst 33258 staining and flow cytometry suggested that the apoptosis rate of ovarian GC apoptosis was significantly increased in the 2,5-HD-treated group. Subsequently, microarray analysis revealed that a total of 5677 mRNAs were differentially expressed, and further GO and KEGG analyses revealed that the differentially expressed genes were significantly enriched in many signaling pathways, including the Hippo pathway. A total of 7 differentially expressed genes that function upstream of the Hippo signaling pathway (Nf2, Wwc1, Ajuba, Llgl1, Dlg3, Rassf6 and Rassf1) were selected to confirm the microarray results by qRT-PCR, and the expression of these genes did change. Subsequently, the expression of key effector genes (Yap1, Mst1 and Lats1) and target genes (Ctgf and Puma) of the Hippo signaling was measured, and the results suggested that the mRNA and protein levels of Yap1, Mst1, Lats1, and Ctgf were significantly decreased while those of Puma were significantly increased after 2,5-HD treatment. Further CO-IP analysis suggested that the interaction between YAP1 and TEAD was significantly reduced after 2,5-HD treatment, while the interaction between YAP1 and P73 was not affected. In summary, during the 2,5-HD-induced apoptosis of ovarian GCs, the Hippo signaling pathway is inhibited, and downregulation of the pro-proliferation gene Ctgf and upregulated of the pro-apoptosis gene Puma are important. Decreased Ctgf expression was associated with decreased binding of YAP1 to TEAD. However, increased PUMA expression was not associated with YAP1 binding to P73.

Hsa_circ_0002348 regulates trophoblast proliferation and apoptosis through miR-126-3p/BAK1 axis in preeclampsia

BACKGROUND

Preeclampsia is a common pregnancy complication characterized by high blood pressure and damage to organs. Abnormal placenta and vascular function can lead to preeclampsia. Accumulating evidence has suggested a potential link between circular RNAs (circRNAs) and preeclampsia. As a placenta and endothelial-expressed circRNA, hsa_circ_0002348, may be promising to be the novel molecular target for preeclampsia. However, the function and mechanism of hsa_circ_0002348 in preeclampsia has not been elucidated.

MATERIALS AND METHODS

An overlap analysis of two circRNA profiles from placenta and endothelial cells was used to identify a functionally unknown circRNA, hsa_circ_0002348. Quantitative real-time PCR (qRT-PCR) and in situ hybridization (ISH) were used to detect its expression in the trophoblast cells and placental tissues. The mouse model of lipopolysaccharide (LPS)-induced preeclampsia was established to determine the in vivo role of hsa_circ_0002348. RNA immunoprecipitation (RIP), Luciferase reporter assay, qRT-PCR, western blot, gain- and loss-of-function and rescue experiments were conducted to uncover the role of hsa_circ_0002348 and its interaction with miR-126-3p and BAK1 in regulating trophoblast proliferation and apoptosis. Fluorescence in situ hybridization (FISH) and Immunohistochemistry (IHC) were performed to examine the expression of miR-126-3p and BAK1 in mice and human placentas, respectively.

RESULTS

Hsa_circ_0002348 was significantly increased in the preeclampsia placentas, and positively correlated with the severity of preeclampsia patients' clinical manifestations. Its overexpression exacerbated preeclampsia-like features in the mouse model of LPS-induced preeclampsia. Functionally, hsa_circ_0002348 was found to inhibit trophoblast proliferation and promote trophoblast apoptosis. Mechanistically, hsa_circ_0002348, as an endogenous miR-126-3p sponge, upregulated the expression of BAK1. Additionally, both hsa_circ_0002348 knockdown and miR-126-3p overexpression enhanced the mammalian target of rapamycin (mTOR) and ERK1/2 signaling pathway.

CONCLUSIONS

Hsa_circ_0002348 might be a novel regulator of trophoblast proliferation and apoptosis through miR-126-3p/BAK1 axis in preeclampsia, which may serve as a potential target for detecting and treating preeclampsia.

Lnc001209 Participates in aluminium-induced apoptosis of PC12 cells by regulating PI3K-AKT-mTOR signalling pathway

Aluminium (Al) is a common environmental neurotoxin, but the molecular mechanism underlying its toxic effects remains unclear. Many studies have shown that aluminium exposure leads to increased neuronal apoptosis. This study aimed to investigate the mechanisms and signalling pathways involved in aluminium exposure-induced neuronal apoptosis. The results showed a decrease in the number of PC12 cells and changes in cell morphology in the aluminium maltol exposure group. The viability of PC12 cells decreased gradually with increasing of exposure doses, and the apoptosis rate increased. The expression of Lnc001209 decreased gradually with an increase in the aluminium exposure dose. After transfection of Lnc001209 siRNA in aluminium-exposed PC12 cells, the protein expression levels of p-Akt Ser473, p-Akt Thr308, p-P85 Tyr467, p-mTOR Ser2448 and CD36 were increased. RNA pull-down MS showed that Lnc001209 interacts with the CD36 protein. Expression of the CD36 protein was increased in PC12 cells exposed to aluminium. The results of the CD36 intervention experiment showed that the protein expression levels of p-Akt Ser473, p-Akt Thr308, p-P85 Tyr467, and p-mTOR Ser2448 likely increased after CD36 overexpression. In addition, the phosphorylation level of AKT had the most significant increase. The enhancement of p-Akt activity promotes neuronal apoptosis.

Melatonin Protects the Apoptosis of Sheep Granulosa Cells by Suppressing Oxidative Stress via MAP3K8 and FOS Pathway

Melatonin is not only a highly effective active oxygen scavenger but also an important reproductive hormone. Melatonin has a regulatory effect on animal reproduction, especially on the ovaries. It can affect the proliferation and apoptosis of cells in follicles. However, the mechanisms of the dual antioxidation and anti-apoptosis effects of melatonin on granulosa cells are still not clear, especially in sheep. Therefore, we investigated the mechanisms of the protective effect of melatonin against oxidative damage in granulosa cells. At a concentration of 250 µmol/L, H₂O₂ promoted granulosa cell apoptosis; however, 10 ng/mL melatonin effectively alleviated the pro-apoptotic effect of H₂O₂. Furthermore, through the application of high-throughput sequencing technology, we identified 109 significantly differentially expressed genes (35 upregulated and 74 downregulated genes) involved in the protective effect of melatonin against apoptosis. The expression levels of nine related genes, i.e., ATF3, FIBIN, FOS, HSPA6, MAP3K8, FOSB, PET117, DLX2, and TRIB1, changed significantly. MAP3K8 and FOS gene overexpression impacted the protective effect of melatonin in granulosa cells; the two genes exhibited an upstream and downstream regulatory relationship. Our findings indicated that melatonin alleviated H₂O₂-induced apoptosis in sheep granulosa cells through the MAP3K8-FOS pathway.

Synergistic actions of Alpelisib and Melatonin in breast cancer cell lines with PIK3CA gene mutation

AIMS

Breast cancer (BC) presents high mortality rate and about 25-46 % have mutation in the PIK3CA gene. Alpelisib is a PI3K inhibitor that acts on p110α, which is a subunit of the PI3K protein. The melatonin shown important anti-neoplastic effects and may increase the effectiveness of chemotherapy. This study evaluated the synergistic action of Alpelisib and Melatonin in BC lines carrying the H1047R mutation in PIK3CA, relative to the cellular dynamics and the PI3K/AKT/mTOR pathway.

MAIN METHODS

MDA-MB-468 (triple-ernegative), MDA-MB-453 (H1047R PIK3CA, HER2+) and T-47D cells (H1047R PIK3CA, ER+/PR+) were divided into four treatment groups: control; Melatonin (1 mM); Alpelisib (1 μM); and Alpelisib (1 μM) + Melatonin (1 mM). Cell viability and migration were investigated using the MTT assay and Transwell assay, respectively. Protein expression of PI3K, p-AKT, mTOR, HIF-1α, and caspase-3, was verified using immunocytochemistry.

KEY FINDINGS

MTT assay revealed that MDA-MB-453 and T-47D showed reduction in cell viability in all groups, especially in the MDA-MB-453 treated with Melatonin + Alpelisib. MDA-MB-468 presents reduction in cell migration only with Melatonin, while in the lines with mutation, the treatment of Melatonin + Alpelisib caused inhibition of cell migration. PI3K, p-AKT, mTOR and HIF-1α were inhibited after treatment with Melatonin + Alpelisib in MDA-MB-453 and T-47D lines. The expression of caspase-3 increased in all groups in MDA-MB-453 and T-47D cells, being the increase more pronounced in the Melatonin + Alpelisib group.

SIGNIFICANCE

These results indicate that the combined use of Melatonin and Alpelisib may be more effective in inhibiting BC in women carrying the PIK3CA gene mutation than either treatment alone.

Transcriptomic screening to identify hub genes and drug signatures for PCOS based on RNA-Seq data in granulosa cells

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the most incident reproductive diseases, and remains the main cause of female infertility. Granulosa cells play a critical role in normal follicle development and steroid hormones synthesis. In spite of extensive research, no sole medication has been approved by FDA to treat PCOS. This study aimed to investigate the novel therapeutics targets in PCOS, focusing on granulosa cells transcriptome functional analysis with a drug repositioning approach.

METHODS

PCOS microarray and RNA-Seq datasets in granulosa cells were screened and reanalyzed. KEGG pathway enrichment and interaction network analyses were performed and followed by a set of drug signature screening and Poly-pharmacology survey.

RESULTS

545 deregulated genes were identified via filters including p_adj < 0.05 and |log2FC| > 1. Amongst the top 15 KEGG pathways significantly enriched, metabolism of xenobiotics by cytochrome P450, steroid hormone biosynthesis and ovarian steroidogenesis were observed. The Protein-Protein Interaction network identified 18 hub genes amongst this set. Interestingly, most candidate drug signatures have been introduced by databases are either FDA approved or entered into clinical trials, including melatonin, resveratrol and raloxifene. Investigational or experimental introduced drugs obey rules of drug-likeness with almost safe and acceptable ADMET properties. Notably, 21 top target genes of the final drug set were also included in the granulosa significant differentially expressed genes.

CONCLUSION

Results of the current study represent approved, investigational and experimental drug signatures according to the differentially expressed genes in granulosa cells with supported literature reviews. This data might be useful for researchers and clinicians to pave the way for better management of PCOS.

Se-Enriched Cardamine violifolia Improves Laying Performance and Regulates Ovarian Antioxidative Function in Aging Laying Hens

As a selenium-enriched plant, Cardamine violifolia (SEC) has an excellent antioxidant function. The edibility of SEC is expected to develop new sources of organic Se supplementation for human and animal nutrition. This study was conducted to investigate the effects of SEC on laying performance and ovarian antioxidant capacity in aging laying hens. A total of 450 laying hens were assigned to five treatments. Dietary treatments included the following: a basal diet (diet without Se supplementation, CON) and basal diets supplemented with 0.3 mg/kg Se from sodium selenite (SS), 0.3 mg/kg Se from Se-enriched yeast (SEY), 0.3 mg/kg Se from SEC, or 0.3 mg/kg Se from SEC and 0.3 mg/kg Se from SEY (SEC + SEY). Results showed that supplementation with SEC tended to increase the laying rate, increased the Haugh unit of eggs, and reduced the FCR. SEC promoted ovarian cell proliferation, inhibited apoptosis, and ameliorated the maintenance of follicles. SEC, SEY, or SEC + SEY increased ovarian T-AOC and decreased MDA levels. SEC increased the mRNA abundance of ovarian selenoproteins. SEC and SEC + SEY increased the mRNA abundance of Nrf2, HO-1, and NQO1, and decreased the mRNA abundance of Keap1. These results indicate that SEC could potentially to improve laying performance and egg quality via the enhancement of ovarian antioxidant capacity. SEC exerts an antioxidant function through the modulation of the Nrf2/Keap1 signaling pathway.

Melatonin: A potential adjuvant therapy for septic myopathy

Septic myopathy, also known as ICU acquired weakness (ICU-AW), is a characteristic clinical symptom of patients with sepsis, mainly manifested as skeletal muscle weakness and muscular atrophy, which affects the respiratory and motor systems of patients, reduces the quality of life, and even threatens the survival of patients. Melatonin is one of the hormones secreted by the pineal gland. Previous studies have found that melatonin has anti-inflammatory, free radical scavenging, antioxidant stress, autophagic lysosome regulation, mitochondrial protection, and other multiple biological functions and plays a protective role in sepsis-related multiple organ dysfunction. Given the results of previous studies, we believe that melatonin may play an excellent regulatory role in the repair and regeneration of skeletal muscle atrophy in septic myopathy. Melatonin, as an over-the-counter drug, has the potential to be an early, complementary treatment for clinical trials. Based on previous research results, this article aims to critically discuss and review the effects of melatonin on sepsis and skeletal muscle depletion.

Phosphoproteomics Profile of Chicken Cecum in the Response to Salmonella enterica Serovar Enteritidis Inoculation

Salmonella enterica serovar Enteritidis (S. Enteritidis) is a foodborne pathogen, which can cause great threats to human health through the consumption of contaminated poultry products. This research combines TMT labeling, HPLC and mass-spectrometry-based phosphoproteomics on cecum of the F1 cross of Guangxi Yao chicken and Jining Bairi chicken. The treated group was inoculated with 0.3 mL inoculum S. Enteritidis, and the control group was inoculated with 0.3 mL phosphate-buffered saline (PBS). A total of 338 differentially phosphorylated modification sites in 243 differentially phosphorylated proteins (DPPs) were chosen for downstream analyses. A total of 213 sites in 146 DPPs were up-regulated and 125 sites in 97 DPPs were down-regulated. Functional analysis was performed for DPPs based on gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and the protein domain. The DPPs were mainly enriched in immune- and metabolic-related GO-BP (biological process) and KEGG pathways. We predicted and classified the subcellular structure and COG/KOG of DPPs. Furthermore, protein-protein interaction network analyses were performed by using multiple algorithms. We identified 71 motifs of the phosphorylated modification sites and selected 18 sites randomly to detect the expression level through parallel reaction monitoring (PRM). S. Enteritidis inoculation caused phosphorylation alteration in immune- and metabolic-related proteins. The invasion of S. Enteritidis may be actualized by inducing cecum cell apoptosis through the endoplasmic reticulum pathway, and chickens could resist the invasion of S. Enteritidis by affecting the function of ECM receptors. The findings herein provide a crucial theoretical foundation to understand the molecular mechanism and epigenetic regulation in response to S. Enteritidis inoculation in chickens.

Totipotency of miR-184 in porcine granulosa cells

Estradiol (E₂) synthesis, cell proliferation and the apoptosis of porcine granulosa cells (GCs) affect follicular growth and development. The miR-184 level in ovary tissues of Yorkshire × Landrace sows was significantly higher in high-yielding sows than that in low-yielding sows, which was the same as in Yorkshire sows. However, the roles of miR-184 on E₂ granulosa cells (GCs) are still unclear. We found that miR-184 promoted E₂ synthesis and proliferation but inhibited apoptosis in GCs by targeting nuclear receptor subfamily 1 group D member 1 (NR1D1), cyclin dependent kinase inhibitor 1A (P21,CDKN1A) and homeodomain interacting protein kinase 2 (HIPK2) respectively. These findings indicated that miR-184 is a novel key factor that regulates the physiological functions of GCs.

mTORC1 Mediates the Processes of Lysine Regulating Satellite Cells Proliferation, Apoptosis, and Autophagy

Lysine (Lys) is essential for skeletal muscle growth and protein synthesis in mammals. However, the regulatory network underlying Lys-regulated skeletal muscle development is unknown. To determine whether any cross-talk occurs among mammalian targets of rapamycin complex 1 (mTORC1) and Lys in the regulation of muscle satellite cells (SCs) proliferation, we applied the treatment rapamycin (a mTORC1 inhibitor) and MHY1485 (a mTORC1 activator) on Lys-added or -deficient SCs. The results show Lys deprivation significantly decreases SCs viability, protein synthesis, and cell cycling, increases autophagy and apoptosis, and inhibits the mTORC1 signaling pathway. Restoration of Lys content significantly attenuates this effect. mTORC1 signaling pathway activation during Lys deprivation or mTORC1 signaling pathway inhibition during Lys addition attenuates the effect of Lys deprivation or addition on SCs viability, protein synthesis, cell cycling, autophagy, and apoptosis. In conclusion, Lys could improve SCs proliferation, and inhibit SCs apoptosis and autophagy, via the mTORC1 signaling pathway.

Hand2os1 Regulates the Secretion of Progesterone in Mice Corpus Luteum

The corpus luteum plays a key role in pregnancy maintenance and estrous cycle regulation by secreting progesterone. Hand2os1 is an lncRNA located upstream of Hand2, with which a bidirectional promoter is shared and is involved in the regulation of cardiac development and embryo implantation in mice. The aim of this study was to investigate the expression and regulation of Hand2os1 in the ovaries. Here, we used RNAscope to detect differential expression of Hand2os1 in the ovaries of cycling and pregnant mice. Hand2os1 was specifically detected in luteal cells during the proestrus and estrus phases, showing its highest expression in the corpus luteum at estrus. Additionally, Hand2os1 was strongly expressed in the corpus luteum on day 4 of pregnancy, but the positive signal progressively disappeared after day 8, was detected again on day 18, and gradually decreased after delivery. Hand2os1 significantly promoted the synthesis of progesterone and the expression of StAR and Cyp11a1. The decreased progesterone levels caused by Hand2os1 interference were rescued by the overexpression of StAR. Our findings suggest that Hand2os1 may regulate the secretion of progesterone in the mouse corpus luteum by affecting the key rate-limiting enzyme StAR, which may have an impact on the maintenance of pregnancy.

Physicochemical, Nutritional Properties and Metabolomics Analysis Fat Deposition Mechanism of Chahua Chicken No. 2 and Yao Chicken

Poultry is an important dietary source of animal protein, accounting for approximately 30% of global meat consumption. Because of its low price, low fat and cholesterol content, and no religious restrictions, chicken is considered a widely available healthy meat. Chahua chicken No. 2 is a synthetic breed of Chahua chicken derived from five generations of specialized strain breeding. In this study, Chahua chicken No. 2 (CH) and Yao chicken (Y) were used as the research objects to compare the differences in physicochemical and nutritional indicators of meat quality between the two chicken breeds, and metabolomics was used to analyze the differences in metabolites and lipid metabolism pathways and to explore the expression of genes involved in adipogenesis. The physical index and nutritional value of CH are better than that of Y, and the chemical index of Y is better than that of CH. However, the chemical index results of CH are also within the normal theoretical value range. Comprehensive comparison shows that the meat quality of CH is relatively good. Metabolomics analysis showed that CH and Y had 85 different metabolites, and the differential metabolites were mainly classified into eight categories. KEGG pathway enrichment analysis revealed 13 different metabolic pathways. The screened PPARG, FABP3, ACSL5, FASN, UCP3 and SC5D were negatively correlated with muscle fat deposition, while PPARα, ACACA and ACOX1 were positively correlated with muscle fat deposition. The meat quality of CH was better than Y. The metabolites and metabolic pathways obtained by metabonomics analysis mainly involved the metabolism of amino acids and fatty acids, which were consistent with the differences in meat quality between the two breeds and the contents of precursors affecting flavor. The screened genes were associated with fatty deposition in poultry.

Resveratrol Alleviating the Ovarian Function Under Oxidative Stress by Alternating Microbiota Related Tryptophan-Kynurenine Pathway

Oxidative stress (OS) is a key factor regulating the systemic pathophysiological effects and one of the fundamental mechanisms associated with aging and fertility deterioration. Previous studies revealed that resveratrol (RV) exhibits a preventive effect against oxidative stress in the ovary. However, it remains unknown whether gut microbiota respond to resveratrol during an OS challenge. In Exp. 1, layers received intraperitoneal injection of tert-butyl hydroperoxide (tBHP) (0 or 800 μmol/kg BW) or received resveratrol diets (0 or 600 mg/kg) for 28 days. In Exp. 2, the role of intestinal microbiota on the effects of resveratrol on tBHP-induced oxidative stress was assessed through fecal microbiota transplantation (FMT). The OS challenge reduced the egg-laying rate and exhibited lower pre-hierarchical follicles and higher atretic follicles. Oral RV supplementation ameliorated the egg-laying rate reduction and gut microbiota dysbiosis. RV also reversed the tryptphan-kynurenine pathway, upregulated nuclear factor E2-related factor 2 (Nrf2) and silent information regulator 1(SIRT1) levels, and decreased the expression of forkhead box O1 (FoxO1) and P53. These findings indicated that the intestinal microbiota-related tryptophan-kynurenine pathway is involved in the resveratrol-induced amelioration of ovary oxidative stress induced by tBHP in the layer model, while SIRT1-P53/FoxO1 and Nrf2-ARE signaling pathway were involved in this process.

Grade follicles transcriptional profiling analysis in different laying stages in chicken

During follicular development, a series of key events such as follicular recruitment and selection are crucially governed by strict complex regulation. However, its molecular mechanisms remain obscure. To identify the dominant genes controlling chicken follicular development, the small white follicle (SWF), the small yellow follicle (SYF), and the large yellow follicle (LYF) in different laying stages (W22, W31, W51) were collected for RNA sequencing and bioinformatics analysis. There were 1866, 1211, and 1515 differentially expressed genes (DEGs) between SWF and SYF in W22, W31, and W51, respectively. 4021, 2295, and 2902 DEGs were respectively identified between SYF and LYF in W22, W31, and W51. 5618, 4016, and 4809 DEGs were respectively identified between SWF and LYF in W22, W31, and W51. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that extracellular matrix, extracellular region, extracellular region part, ECM-receptor interaction, collagen extracellular matrix, and collagen trimer were significantly enriched (P < 0.05). Protein–protein interaction analysis revealed that COL4A2, COL1A2, COL4A1, COL5A2, COL12A1, ELN, ALB, and MMP10 might be key candidate genes for follicular development in chicken. The current study identified dominant genes and pathways contributing to our understanding of chicken follicular development. 

Polymorphism in the 5' regulatory region of CTNNB1 gene and association with age at first lay and egg production

1. The Wnt signalling pathway is centred on the fact that catenin beta-1(CTNNB1) participates in the regulation of ovarian follicle development. The aim of the following study was to identify the polymorphism in the 5' regulatory region of the chicken CTNNB1 gene and evaluate the association between SNPs and egg production traits.2. The study demonstrated that the 5' regulatory region of the CTNNB1 gene has ten SNPs in the chicken flock. After Bonferroni correction for multiple testing, five SNPs (rs315692306, 2:g43385123, rs735854102, 2:g43385457 and rs737907370) were significantly correlated with egg laying traits.3. An association study of the haplotypes with egg laying traits revealed that both haplotypes in block 1 (consisting of rs735052881, rs740662190, rs315692306, and 2:43385123) and block 2 (consisting of rs735854102 and 2:g43385457) were associated with point of lay age and the number of eggs laid at 18-23 weeks. Prediction of transcription factor binding sites showed that transcription factors changed after mutation in block 2. The luciferase assay revealed that the priming activity of the CA haplotype in block2 was the highest.4. Taken together, the rs315692306, 2:g43385123, rs735854102, 2:g43385457 and rs737907370 in the 5' regulatory region of the CTNNB1 gene have significant impacts on egg production.

[Extranuclear p53 suppresses autophagy through AMPK/mTOR signaling to promote heat stress-induced vascular endothelial cell damage]

OBJECTIVE

To explore the role of extranuclear p53-mediated autophagy suppression by regulating AMPK/mTOR signaling pathway in heat stress (HS)-induced injury of mouse aortic endothelial cells (MAECs).

METHODS

Primary cultures of MAECs were pretreated with compound C (an AMPK inhibitor), rapamycin (a mTOR inhibitor) or pifithrin-α (PFT, a selective p53 inhibitor) for 1 h before exposure to HS (43 ℃) for 2 h. The changes in cell viability at different time points after HS were examined using CCK-8 assay, and the protein expressions of P53, LC3-II, Beclin-1, p62 and the AMPK/mTOR signaling proteins were detected using Western blotting. In the animal experiment, C57 mice were pretreated with compound C, rapamycin or PFT and exposed to a high temperature at 40 ℃ to induce HS. The pathological changes in the aorta of the mice were observed with HE staining, and cell apoptosis was detected using TUNEL staining.

RESULTS

In cultured MAECs, the cell viability was significantly reduced (P < 0.05) and the mitochondrial fraction of p53 increased while its cytoplasmic fraction decreased progressively over time following HS. HS significantly lowered the expressions of LC3-II and Beclin-1, increased p62 level, suppressed AMPK phosphorylation, and increased mTOR phosphorylation and the expressions of its downstream proteins at 6 h after the exposure (P < 0.05). Pretreatment with compound C significantly inhibited LC3-II and Beclin- 1 expression, enhanced p62 expression, and aggravated HS-induced cell injury and apoptosis in MAECs; rapamycin treatment produced the opposite effects (P < 0.05). PFT treatment significantly enhanced the viability of MAECs and alleviated HSinduced injury and apoptosis; PFT also significantly promoted activation of AMPK phosphorylation, inhibited mTOR phosphorylation and its downstream proteins (P < 0.05), enhanced the expressions of LC3-II and Beclin 1, and inhibited p62 expression in the MAECs (P < 0.05). In C57 mice, HS resulted in swelling, shedding and apoptosis of aortic vascular endothelial cells. Pretreatment with compound C obviously aggravated HS-induced vascular injury and endothelial cell apoptosis, while pretreatment with either rapamycin or PFT significantly alleviated these injuries.

CONCLUSION

Autophagy inhibition mediated by extranuclear p53 via inhibiting AMPK activity and activating mTOR signaling participates in HS-induced injury of MAECs.

The Effect of Oxidative Stress on the Chicken Ovary: Involvement of Microbiota and Melatonin Interventions

The poultry ovary is used as a classic model to study ovarian biology and ovarian cancer. Stress factors induced oxidative stress to cause follicle atresia, which may be a fundamental reason for the reduction in fertility in older laying hens or in aging women. In the present study, we set out to characterize the relationships between oxidative stress and ovarian function. Layers (62 weeks of age; BW = 1.42 ± 0.12 kg) were injected with tert-butyl hydroperoxide (tBHP) at 0 (CON) and 800 μmol/kg BW (oxidative stress group, OS) for 24 days and the role of melatonin (Mel) on tBHP-induced ovary oxidative stress was assessed through ovary culture in vitro. The OS (800 μmol/kg BW tert-butyl hydroperoxide) treatment decreased the reproduction performance and ovarian follicle numbers. OS decreased the expression of SIRT1 and increased the P53 and FoxO1 expression of the ovary. A decreased Firmicutes to Bacteroidetes ratio, enriched Marinifilaceae (family), Odoribacter (genus) and Bacteroides_plebeius (species) were observed in the cecum of the OS group. Using Mel in vitro enhanced the follicle numbers and decreased the ovary cell apoptosis induced by tBHP. In addition, it increased the expression of SIRT1 and decreased the P53 and FoxO1 expression. These findings indicated that oxidative stress could decrease the laying performance, ovarian function and influence gut microbiota and body metabolites in the layer model, while the melatonin exerts an amelioration the ovary oxidative stress through SIRT1-P53/FoxO1 pathway.