Biochemical and Molecular Insights into Variation in Sesame Seed Antioxidant Capability as Revealed by Metabolomics and Transcriptomics Analysis.

Sesame seeds are important resources for relieving oxidation stress-related diseases. Although a significant variation in seeds' antioxidant capability is observed, the underlying biochemical and molecular basis remains elusive. Thus, this study aimed to reveal major seed components and key molecular mechanisms that drive the variability of seeds' antioxidant activity (AOA) using a panel of 400 sesame accessions. The seeds' AOA, total flavonoid, and phenolic contents varied from 2.03 to 78.5%, 0.072 to 3.104 mg CAE/g, and 2.717 to 21.98 mg GAE/g, respectively. Analyses revealed that flavonoids and phenolic acids are the main contributors to seeds' AOA variation, irrespective of seed coat color. LC-MS-based polyphenol profiling of high (HA) and low (LA) antioxidant seeds uncovered 320 differentially accumulated phenolic compounds (DAPs), including 311 up-regulated in HA seeds. Tricin, persicoside, 5,7,4',5'-tetrahydro-3',6-dimethoxyflavone, 8-methoxyapigenin, and 6,7,8-tetrahydroxy-5-methoxyflavone were the top five up-regulated in HA. Comparative transcriptome analysis at three seed developmental stages identified 627~2357 DEGs and unveiled that differential regulation of flavonoid biosynthesis, phenylpropanoid biosynthesis, and stilbene biosynthesis were the key underlying mechanisms of seed antioxidant capacity variation. Major differentially regulated phenylpropanoid structural genes and transcription factors were identified. SINPZ0000571 (MYB), SINPZ0401118 (NAC), and SINPZ0500871 (C3H) were the most highly induced TFs in HA. Our findings may enhance quality breeding.

Estrogen promotes gonadotropin-releasing hormone expression by regulating tachykinin 3 and prodynorphin systems in chicken.

The "KNDy neurons" located in the hypothalamic arcuate nucleus (ARC) of mammals are known to co-express kisspeptin, neurokinin B (NKB), and dynorphin (DYN), and have been identified as key mediators of the feedback regulation of steroid hormones on gonadotropin-releasing hormone (GnRH). However, in birds, the genes encoding kisspeptin and its receptor GPR54 are genomic lost, leaving unclear mechanisms for feedback regulation of GnRH by steroid hormones. Here, the genes tachykinin 3 (TAC3) and prodynorphin (PDYN) encoding chicken NKB and DYN neuropeptides were successfully cloned. Temporal expression profiling indicated that TAC3, PDYN and their receptor genes (TACR3, OPRK1) were mainly expressed in the hypothalamus, with significantly higher expression at 30W than at 15W. Furthermore, overexpression or interference of TAC3 and PDYN can regulate the GnRH mRNA expression. In addition, in vivo and in vitro assays showed that estrogen (E2) could promote the mRNA expression of TAC3, PDYN, and GnRH, as well as the secretion of GnRH/LH. Mechanistically, E2 could dimerize the nuclear estrogen receptor 1 (ESR1) to regulate the expression of TAC3 and PDYN, which promoted the mRNA and protein expression of GnRH gene as well as the secretion of GnRH. In conclusion, these results revealed that E2 could regulate the GnRH expression through TAC3 and PDYN systems, providing novel insights for reproductive regulation in chickens.

An association between PM2.5 components and respiratory infectious diseases: A China's mainland-based study.

The particulate matter with diameter of less than 2.5 µm (PM2.5) is an important risk factor for respiratory infectious diseases, such as scarlet fever, tuberculosis, and similar diseases. However, it is not clear which component of PM2.5 is more important for respiratory infectious diseases. Based on data from 31 provinces in mainland China obtained between 2013 and 2019, this study investigated the effects of different PM2.5 components, i.e., sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), and organic matter (OM), and black carbon (BC), on respiratory infectious diseases incidence [pulmonary tuberculosis (PTB), scarlet fever (SF), influenza, hand, foot, and mouth disease (HFMD), and mumps]. Geographical probes and the Bayesian kernel machine regression (BKMR) model were used to investigate correlations, single-component effects, joint effects, and interactions between components, and subgroup analysis was used to assess regional and temporal heterogeneity. The results of geographical probes showed that the chemical components of PM2.5 were associated with the incidence of respiratory infectious diseases. BKMR results showed that the five components of PM2.5 were the main factors affecting the incidence of respiratory infectious diseases (PIP>0.5). The joint effect of influenza and mumps by co-exposure to the components showed a significant positive correlation, and the exposure-response curve for a single component was approximately linear. And single-component modelling revealed that OM and BC may be the most important factors influencing the incidence of respiratory infections. Moreover, respiratory infectious diseases in southern and southwestern China may be less affected by the PM2.5 component. This study is the first to explore the relationship between different components of PM2.5 and the incidence of five common respiratory infectious diseases in 31 provinces of mainland China, which provides a certain theoretical basis for future research.

Bacitracin-resistant Staphylococcus aureus induced in chicken gut and in vitro under bacitracin exposure.

It is common knowledge that prolonged and excessive use of antibiotics can lead to antimicrobial resistance. However, the characteristics and mechanism of resistant-bacteria induced by clinically recommended and prophylactic dose drugs remain largely unclear. This study aimed to observe the trends of drug resistance of the bacitracin-susceptible Staphylococcus aureus strain FS127 under exposure to bacitracin (BAC), which were induced in vitro and in chicken gut. Antimicrobial susceptibility testing was used to detect the susceptibility of S. aureus induced in vitro and in the chicken gut to gentamicin, chloramphenicol, tetracycline, doxycycline, penicillin and chloramphenicol. The research results showed that bacitracin could induce drug resistance in S. aureus both in vitro and in vivo. The bacitracin-resistance rate of S. aureus isolated from chicken gut was positively correlated with the dose and time of bacitracin administration. The findings revealed that bacitracin-resistant S. aureus induced in vivo had enhanced susceptibility to chloramphenicol but no such change in vitro. Meanwhile, RT-qPCR assay was used to detect the expression levels of vraD, braD, braR and bacA in typical strains with different bacitracin-resistance levels. It was found that BacA may play a key role in the bacitracin resistance of S. aureus. In conclusion, this work reveals the characteristics and mechanism of bacitracin-resistant S. aureus induced by bacitracin in vivo and in vitro respectively.

Individual and joint associations of per- and polyfluoroalkyl substances (PFAS) with gallstone disease in adults: A cross-sectional study.

Disturbances in the enterohepatic circulation are important biological mechanisms for causing gallstones and also have important effects on the metabolism of Per- and polyfluoroalkyl substances (PFAS). Moreover, PFAS is associated with sex hormone disorder which is another important cause of gallstones. However, it remains unclear whether PFAS is associated with gallstones. In this study, we used logistic regression, restricted cubic spline (RCS), quantile g-computation (qg-comp), Bayesian kernel machine regression (BKMR), and subgroup analysis to assess the individual and joint associations of PFAS with gallstones and effect modifiers. We observed that the individual associations of perfluorodecanoic acid (PFDeA) (OR: 0.600, 95% CI: 0.444 to 0.811), perfluoroundecanoic acid (PFUA) (OR: 0.630, 95% CI: 0.453 to 0.877), n-perfluorooctane sulfonic acid (n-PFOS) (OR: 0.719, 95% CI: 0.571 to 0.906), and perfluoromethylheptane sulfonic acid isomers (Sm-PFOS) (OR: 0.768, 95% CI: 0.602 to 0.981) with gallstones were linearly negative. Qg-comp showed that the PFAS mixture (OR: 0.777, 95% CI: 0.514 to 1.175) was negatively associated with gallstones, but the difference was not statistically significant, and PFDeA had the highest negative association. Moreover, smoking modified the association of perfluorononanoic acid (PFNA) with gallstones. BKMR showed that PFDeA, PFNA, and PFUA had the highest groupPIP (groupPIP = 0.93); PFDeA (condPIP = 0.82), n-perfluorooctanoic acid (n-PFOA) (condPIP = 0.68), and n-PFOS (condPIP = 0.56) also had high condPIPs. Compared with the median level, the joint association of the PFAS mixture with gallstones showed a negative trend; when the PFAS mixture level was at the 70th percentile or higher, they were negatively associated with gallstones. Meanwhile, when other PFAS were fixed at the 25th, 50th, and 75th percentiles, PFDeA had negative associations with gallstones. Our evidence emphasizes that PFAS is negatively associated with gallstones, and more studies are needed in the future to definite the associations of PFAS with gallstones and explore the underlying biological mechanisms.

Plasma metabolites and risk of myocardial infarction: a bidirectional Mendelian randomization study.

BACKGROUND: Myocardial infarction (MI) is a critical cardiovascular event with multifaceted etiology, involving several genetic and environmental factors. It is essential to understand the function of plasma metabolites in the development of MI and unravel its complex pathogenesis. METHODS: This study employed a bidirectional Mendelian randomization (MR) approach to investigate the causal relationships between plasma metabolites and MI risk. We used genetic instruments as proxies for plasma metabolites and MI and conducted MR analyses in both directions to assess the impact of metabolites on MI risk and vice versa. In addition, the large-scale genome-wide association studies datasets was used to identify genetic variants associated with plasma metabolite (1400 metabolites) and MI (20,917 individuals with MI and 440,906 individuals without MI) susceptibility. Inverse variance weighted was the primary method for estimating causal effects. MR estimates are expressed as beta coefficients or odds ratio (OR) with 95% CI. RESULTS: We identified 14 plasma metabolites associated with the occurrence of MI (P < 0.05), among which 8 plasma metabolites [propionylglycine levels (OR = 0.922, 95% CI: 0.881-0.965, P < 0.001), gamma-glutamylglycine levels (OR = 0.903, 95% CI: 0.861-0.948, P < 0.001), hexadecanedioate (C16-DC) levels (OR = 0.941, 95% CI: 0.911-0.973, P < 0.001), pentose acid levels (OR = 0.923, 95% CI: 0.877-0.972, P = 0.002), X-24546 levels (OR = 0.936, 95% CI: 0.902-0.971, P < 0.001), glycine levels (OR = 0.936, 95% CI: 0.909-0.964, P < 0.001), glycine to serine ratio (OR = 0.930, 95% CI: 0.888-0.974, P = 0.002), and mannose to trans-4-hydroxyproline ratio (OR = 0.912, 95% CI: 0.869-0.958, P < 0.001)] were correlated with a decreased risk of MI, whereas the remaining 6 plasma metabolites [1-palmitoyl-2-arachidonoyl-GPE (16:0/20:4) levels (OR = 1.051, 95% CI: 1.018-1.084, P = 0.002), behenoyl dihydrosphingomyelin (d18:0/22:0) levels (OR = 1.076, 95% CI: 1.027-1.128, P = 0.002), 1-stearoyl-2-docosahexaenoyl-GPE (18:0/22:6) levels (OR = 1.067, 95% CI: 1.027-1.109, P = 0.001), alpha-ketobutyrate levels (OR = 1.108, 95% CI: 1.041-1.180, P = 0.001), 5-acetylamino-6-formylamino-3-methyluracil levels (OR = 1.047, 95% CI: 1.019-1.076, P < 0.001), and N-acetylputrescine to (N (1) + N (8))-acetylspermidine ratio (OR = 1.045, 95% CI: 1.018-1.073, P < 0.001)] were associated with an increased risk of MI. Furthermore, we also observed that the mentioned relationships were unaffected by horizontal pleiotropy (P > 0.05). On the contrary, MI did not lead to significant alterations in the levels of the aforementioned 14 plasma metabolites (P > 0.05 for each comparison). CONCLUSIONS: Our bidirectional MR study identified 14 plasma metabolites associated with the occurrence of MI, among which 13 plasma metabolites have not been reported previously. These findings provide valuable insights for the early diagnosis of MI and potential therapeutic targets.

Whole-transcriptome sequencing reveals a melanin-related ceRNA regulatory network in the breast muscle of Xichuan black-bone chicken.

The economic losses incurred due to reduced muscle pigmentation highlight the crucial role of melanin-based coloration in the meat of black-bone chickens. Melanogenesis in the breast muscle of black-bone chickens is currently poorly understood in terms of molecular mechanisms. This study employed whole-transcriptome sequencing to analyze black and white breast muscle samples from black-bone chickens, leading to the identification of 367 differentially expressed (DE) mRNAs, 48 DElncRNAs, 104 DEcircRNAs, and 112 DEmiRNAs involved in melanin deposition. Based on these findings, a competitive endogenous RNA (ceRNA) network was developed to better understand the complex mechanisms of melanin deposition. Furthermore, our analysis revealed key DEmRNAs (TYR, DCT, EDNRB, MLPH and OCA2) regulated by DEmiRNAs (gga-miR-140-5p, gga-miR-1682, gga-miR-3529, gga-miR-499-3p, novel-m0012-3p, gga-miR-200b-5p, gga-miR-203a, gga-miR-6651-5p, gga-miR-7455-3p, gga-miR-31-5p, miR-140-x, miR-455-x, novel-m0065-3p, gga-miR-29b-1-5p, miR-455-y, novel-m0085-3p, and gga-miR-196-1-3p). These DEmiRNAs competitively interacted with DElncRNAs including MSTRG.2609.2, MSTRG.4185.1, LOC112530666, LOC112533366, LOC771030, LOC107054724, LOC121107411, LOC100859072, LOC101750037, LOC121108550, LOC121109224, LOC121110876, and LOC101749016, as well as DEcircRNAs, such as novel_circ_000158, novel_circ_000623, novel_001518, and novel_circ_003596. The findings from this study provide insight into the mechanisms that regulate lncRNA, circRNA, miRNA, and mRNA expression in chicken melanin deposition.

[Research Progress of Circular RNA in Acute Myeloid Leukemia --Review].

Acute myeloid leukemia(AML) is a malignant tumor of the blood system that is highly heterogeneous in terms of pathogenesis, genetic background and prognostic outcome, with an extremely high fatality rate and recurrence rate. Therefore, exploring new treatment methods and diagnostic strategies is one of the ways to improve the survival rate of patients with acute myeloid leukemia. Circular RNA (circRNA) is a special kind of noncoding RNA, which plays an important role in gene transcription, translation and epigenetic modification, and participates in the disease progression and prognosis of multiple solid tumors. At present, it has found that the abnormal expression of circRNA is closely related to the occurrence, development, drug resistance and prognosis of acute myeloid leukemia.Clinically, it can be used as a new biomarker and potential therapeutic target for AML. This article briefly reviews the research progress of circRNA in acute myeloid leukemia, aiming to provide new strategies for optimizing the diagnosis, treatment and prognosis of leukemia.

Therapeutic effect of yinchenhao decoction on cholelithiasis via mucin in the gallbladder and intestine.

Cholelithiasis is a common and frequently occurring disease worldwide that belongs to the category of jaundice in traditional Chinese medicine. Yinchenhao decoction (YD) consists of Artemisia capillaris Thunb., Gardenia jasminoides J.Ellis, and Rheum palmatum L., and is traditionally used to treat jaundice, which has a significant therapeutic effect on cholelithiasis. Our study aimed to investigate the pathological mechanism of cholelithiasis and the therapeutic mechanism of YD via mucin in the gallbladder and intestine. YD was prepared and analyzed using HPLC. The supersaturation stability experiment was designed by the solvent-shift method. The cell transport experiment was conducted by coculture monolayers. The animal experiment was performed using a cholelithiasis model with a high-cholesterol diet. The related indicators were detected by automatic biochemical analyzer, PCR, western blot, or ELISA. Statistics were analyzed using χ2-tests and t-tests. As the results, in cholelithiasis, MUC5AC highly expressed in the gallbladder shortened cholesterol supersaturation and promoted cholesterol crystallization via the inflammatory cytokine signaling pathway; MUC2 highly expressed in the small intestine prolonged cholesterol supersaturation and promoted cholesterol absorption via the inflammatory cytokine signaling pathway. YD inhibited mucin expression in the gallbladder and intestine in a concentration-dependent manner for cholelithiasis treatment by inhibiting the inflammatory cytokine signaling pathway, which was attributed to the active components, including chlorogenic acid, geniposide, and rhein.

miR-19b-3p regulated by estrogen controls lipid synthesis through targeting MSMO1 and ELOVL5 in LMH cells.

miR-19b-3p is reported to undertake various biological role, while its function and action mechanism in chicken hepatic lipid metabolism is unclear. Conservation analysis and tissue expression pattern of miR-19b-3p and its target gene were evaluated, respectively. Dual luciferase reporter system and Western blot technologies were adopted to validate miR-19b-3p target gene. Overexpression and knockdown assays were done to explore the biological functions of miR-19b-3p and target gene in Leghorn Male Hepatoma cell line (LMH). Regulatory approaches of estrogen on miR-19b-3p and target gene expressions are analyzed through site-directed mutation combined with estrogen receptors antagonist treatment assays. The results showed that chicken miR-19b-3p mature sequences are highly conserved among Capra hircus, Columba livia, Rattus norvegicus, Mus musculus, Cricetulus griseus, Danio rerio, Danio novaehollandiae, Orycodylus porosus, Crocodylus porosus, Gadus morhua, and widely expressed in lung, ovary, spleen, duodenum, kidney, heart, liver, leg muscle, and pectoral muscle tissues. miR-19b-3p could significantly increase intracellular triglyceride (TG) content and decrease intracellular cholesterol (TC) content via targeting methylsterol monooxygenase 1 (MSMO1) and elongase of very long chain fatty acids 5 (ELOVL5), which are highly conserved among species, in both mRNA and protein levels. Estrogen could inhibit miR-19b-3p expression, but directly promoted MSMO1 transcription via estrogen receptor α (ERα) and indirectly regulated ELOVL5 expression at the transcription level. Meanwhile, estrogen could also upregulate MSMO1 and ELOVL5 expression through inhibiting miR-19b-3p expression at the post-transcription level. Taken together, these results highlight the role and regulatory mechanism of miR-19b-3p in hepatic lipid metabolism in chicken, and might produce useful comparative information for human obesity studies and biomedical research.

Prenatal exposure to fine particulate matter chemical constituents and the risk of stillbirth and the mediating role of pregnancy complications: A cohort study.

Evidence on the association of fine particulate matter (PM2.5) exposure with stillbirth is limited and inconsistent, which is largely attributed to differences in PM2.5 constituents. Studies have found that the hazards of certain PM2.5 constituents to the fetus are comparable to or even higher than total PM2.5 mass. However, few studies have linked PM2.5 constituents to stillbirth. Moreover, the mediating role of pregnancy complications in PM2.5-related stillbirth remains unclear. To our knowledge, this study was the first to explore the individual and mixed associations of PM2.5 and its constituents with stillbirth in China. After matching the concentrations of PM2.5 and its constituents (sulfate [SO42-], nitrate [NO3-], ammonium [NH4+], organic matter [OM], and black carbon [BC]) for participants according to their geographical location, there were 170,507 participants included in this study. We found that stillbirth was associated with exposure to PM2.5 and its constituents in the year before pregnancy and during the entire pregnancy, and the associations in trimester 1 were strongest. The risk of stillbirth increased sharply when PM2.5 and its constituents during pregnancy exceeded the median concentrations. Moreover, stillbirth was associated with exposure to the mixtures of SO42-, NO3-, NH4+, OM, and BC before and during pregnancy (trimesters 1 and 2). Meanwhile, two-pollutant models also suggested stillbirth was associated with PM2.5 and its constituents in the year before and during pregnancy. The associations of PM2.5 and its constituents with stillbirth were stronger in mothers with advanced age and without cesarean delivery history. Additionally, hypertensive disorders in pregnancy, gestational diabetes, and placental abruption mediated the association of PM2.5 with stillbirth. Therefore, enhanced protection against PM2.5 for pregnant women before and during pregnancy and targeted interventions for pregnancy complications and anthropogenic sources of PM2.5 constituents are important to reduce stillbirth risk.

Research Note: Development and application of specific molecular identity cards for "Yufen 1" H line chickens.

The "Yufen 1" H line chicken (YF) has excellent characteristics including early sexual maturity and high egg production, and the conservation of its genetic diversity is the core of the breeding activity. To overcome misrepresented breeds and protect the integrity of the germplasm genetic resources, it is important to develop accurate and convenient methods to identify YF. In this study, whole genome resequencing was performed on the YF population, and bioinformatics analysis was conducted by combining the data from different breeds. Linkage disequilibrium (LD) analysis revealed that YF had the slowest LD-decay rate, suggesting strong natural and artificial selection in its history. Through selective sweep analysis, 1,126 selected regions in YF were identified, which contained 163,661 single nucleotide polymorphisms (SNPs). In particular, 5 specific SNPs (SNP1: Chr2:45509616, SNP2: Chr2:45510792, SNP3: Chr9:13788193, SNP4: Chr9:13795646, SNP5: Chr9:13798154) were found exclusively in the YF population. Subsequently, PCR amplification and Sanger sequencing confirmed the presence of these 5 SNPs in YF. Finally, 4 SNPs (SNP1, SNP2, SNP4, SNP5) were screened and verified using the Kompetitive Allele Specific PCR (KASP) typing technique. These SNPs can be used as specific molecular identity cards (IDs) for YF authentication. The present study is of great significance to ensure sustainable conservation and promotion of YF germplasm resources.

Widely targeted metabolic profiling provides insights into variations in bioactive compounds and antioxidant activity of sesame, soybean, peanut, and perilla.

Oilseeds are important sources of diversified nutraceuticals with marked health attributes. Thus, a better understanding of metabolome differences between common oilseeds will be conducive to the food pharmacy. This study aimed to compare the metabolite profiles and antioxidant activity of sesame, soybean, peanut, and perilla seeds and reveal the variation in bioactive compounds. LC-MS-based widely targeted metabolic profiling identified a total of 975 metabolites, of which 753 were common to the four crops. Multivariate analyses unveiled a crop-specific accumulation of metabolites, with 298-388 DAMs (differentially accumulated metabolites) identified. Amino acid metabolism, phenylpropanoid biosynthesis, flavonoid biosynthesis, and lipid metabolism were the most differentially regulated pathways. Furthermore, we revealed the variation in the relative content of 48, 20, 18, 9, 18, 11, and 6 differentially accumulated bioactive flavonoids, phenolic acids, amino acids, vitamins, terpenoids, alkaloids, and coumarins, respectively. Most of the flavonoids accumulated highly in soybean, followed by perilla. Sesame exhibited a better amino acid profile than other oilseeds. DPPH and FRAP assays showed that the antioxidant activity of perilla seed extracts was the highest, followed by soybean, peanut, and sesame. Our results provide data support for the comprehensive use of sesame, perilla, soybean, and peanut seeds in food, and pharmaceutical industries.

Comparative analyses of dynamic transcriptome profiles highlight key response genes and dominant isoforms for muscle development and growth in chicken.

BACKGROUND: Modern breeding strategies have resulted in significant differences in muscle mass between indigenous chicken and specialized broiler. However, the molecular regulatory mechanisms that underlie these differences remain elusive. The aim of this study was to identify key genes and regulatory mechanisms underlying differences in breast muscle development between indigenous chicken and specialized broiler. RESULTS: Two time-series RNA-sequencing profiles of breast muscles were generated from commercial Arbor Acres (AA) broiler (fast-growing) and Chinese indigenous Lushi blue-shelled-egg (LS) chicken (slow-growing) at embryonic days 10, 14, and 18, and post-hatching day 1 and weeks 1, 3, and 5. Principal component analysis of the transcriptome profiles showed that the top four principal components accounted for more than 80% of the total variance in each breed. The developmental axes between the AA and LS chicken overlapped at the embryonic stages but gradually separated at the adult stages. Integrative investigation of differentially-expressed transcripts contained in the top four principal components identified 44 genes that formed a molecular network associated with differences in breast muscle mass between the two breeds. In addition, alternative splicing analysis revealed that genes with multiple isoforms always had one dominant transcript that exhibited a significantly higher expression level than the others. Among the 44 genes, the TNFRSF6B gene, a mediator of signal transduction pathways and cell proliferation, harbored two alternative splicing isoforms, TNFRSF6B-X1 and TNFRSF6B-X2. TNFRSF6B-X1 was the dominant isoform in both breeds before the age of one week. A switching event of the dominant isoform occurred at one week of age, resulting in TNFRSF6B-X2 being the dominant isoform in AA broiler, whereas TNFRSF6B-X1 remained the dominant isoform in LS chicken. Gain-of-function assays demonstrated that both isoforms promoted the proliferation of chicken primary myoblasts, but only TNFRSF6B-X2 augmented the differentiation and intracellular protein content of chicken primary myoblasts. CONCLUSIONS: For the first time, we identified several key genes and dominant isoforms that may be responsible for differences in muscle mass between slow-growing indigenous chicken and fast-growing commercial broiler. These findings provide new insights into the regulatory mechanisms underlying breast muscle development in chicken.

Adiponectin inhibits GnRH secretion via activating AMPK and PI3K signaling pathways in chicken hypothalamic neuron cells.

It has been reported that adiponectin (AdipoQ), an adipokine secreted by white adipose tissue, plays an important role in the control of animal reproduction in addition to its function in energy homeostasis by binding to its receptors AdipoR1/2. However, the molecular mechanisms of AdipoQ in the regulation of animal reproduction remain elusive. In this study, we investigated the effects of AdipoQ on hypothalamic reproductive hormone (GnRH) secretion and reproduction-related receptor gene (estrogen receptor [ER] and progesterone receptor [PR]) expression in hypothalamic neuronal cells (HNCs) of chickens by using real-time fluorescent quantitative PCR (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), Western blot (WB) and cell counting kit-8 (CCK-8) assays and found that overexpression of AdipoQ could increase the expression levels of AdipoR1/2 and reproduction-related receptor genes (P < 0.05) while decreasing the expression level of GnRH. In contrast, interference with AdipoQ mRNA showed the opposite results in HNCs. Furthermore, we demonstrated that AdipoQ exerts its functions through the AMPK and PI3K signaling pathways. Finally, our in vitro experiments found that AdipoRon (a synthetic substitute for AdipoQ) treatment and AdipoR1/2 RNAi interference co-treatment resulted in no effect on GnRH secretion, suggesting that the inhibition of GnRH secretion by AdipoQ is mediated by the AdipoR1/2 signaling axis. In summary, we uncovered, for the first time, the molecular mechanism of AdipoQ in the regulation of reproductive hormone secretion in hypothalamic neurons in chickens.

Integrative analyses of the mRNA expression profile reveal the involvement of STC1 in chicken folliculogenesis.

Efficient ovarian follicle development, maturation, and ovulation are critical for egg production performance. Previous research has underscored the importance of messenger RNAs (mRNAs) in regulating development and folliculogenesis in chicken ovarians. However, the molecular mechanism is not fully understood, especially in the late period of the laying cycle. In the present study, ovarian tissues from 80-week-old Hy-Line Brown layers (three with high and three with low rates of egg laying) were collected for transcriptome sequencing. A total of 306 differentially expressed genes (DEGs) were identified in this study, at a false discovery rate (FDR)-corrected P-value < 0.05 and a log2|fold change| (log2|FC|) ≥1.5. Among these DEGs, stanniocalcin 1 (STC1) was mainly related to cellular processes, single-organism processes, biological regulation, metabolic processes, developmental processes, and reproductive processes. Then, we further investigated the regulation of STC1 during chicken follicle development and found that STC1 inhibited the proliferation and stimulated the apoptosis of follicular granulosa cells (GCs), and decreased the expression of progesterone (P4) and estradiol (E2). Collectively, these results suggest that STC1 plays an important role in chicken follicle development by decreasing GC proliferation and steroidogenesis and stimulating GC apoptosis. This study contributes to the understanding of the reproductive biology of laying hens in the late period of the laying cycle and further lays a foundation for the improvement of egg production in poultry breeding.

The egg production performance of chickens is an essential economic trait that differs significantly between high- and low-egg-laying breeds. In addition to external factors such as feeding, light, and environment, the periodic recruitment of pre-hierarchical follicles and the normal development of hierarchical follicles affect this difference. Thus, we used high-throughput sequencing technology to perform transcriptome analysis of ovarian tissues from 80-wk-old Hy-Line Brown layers with high- and low-egg-laying rates (HH and HL), and an association with the laying performance gene stanniocalcin 1 (STC1) was found. The proliferation and apoptosis of granulosa cells (GCs), as the basic functional cells of ovarian follicles, are highly correlated with the normal development and regression of follicles. Therefore, this study used ovarian follicular GCs cultured in vitro to study the effects of the STC1 gene on the proliferation, apoptosis, and secretion function of GCs and to explore its mechanism of action, laying a foundation for the study of the regulation of the STC1 gene on follicular development.

miR-128-3p inhibits intramuscular adipocytes differentiation in chickens by downregulating FDPS.

BACKGROUND: Intramuscular fat (IMF) content is the major indicator for evaluating chicken meat quality due to its positive correlation with tenderness, juiciness, and flavor. An increasing number of studies are focusing on the functions of microRNAs (miRNAs) in intramuscular adipocyte differentiation. However, little is known about the association of miR-128-3p with intramuscular adipocyte differentiation. Our previous RNA-seq results indicated that miR-128-3p was differentially expressed at different periods in chicken intramuscular adipocytes, revealing a possible association with intramuscular adipogenesis. The purpose of this research was to investigate the biological functions and regulatory mechanism of miR-128-3p in chicken intramuscular adipogenesis. RESULTS: The results of a series of assays confirmed that miR-128-3p could promote the proliferation and inhibit the differentiation of intramuscular adipocytes. A total of 223 and 1,050 differentially expressed genes (DEGs) were identified in the mimic treatment group and inhibitor treatment group, respectively, compared with the control group. Functional enrichment analysis revealed that the DEGs were involved in lipid metabolism-related pathways, such as the MAPK and TGF-ß signaling pathways. Furthermore, target gene prediction analysis showed that miR-128-3p can target many of the DEGs, such as FDPS, GGT5, TMEM37, and ASL2. The luciferase assay results showed that miR-128-3p targeted the 3' UTR of FDPS. The results of subsequent functional assays demonstrated that miR-128-3p acted as an inhibitor of intramuscular adipocyte differentiation by targeting FDPS. CONCLUSION: miR-128-3p inhibits chicken intramuscular adipocyte differentiation by downregulating FDPS. Our findings provide a theoretical basis for the study of lipid metabolism and reveal a potential target for molecular breeding to improve meat quality.

Transcriptomic analysis of mechanism underlying the effect of induced molting on semen quality and reproductive performance in aged Houdan roosters.

The reproductive performance of breeder roosters has significant economic importance in the poultry industry. Breeder roosters have severely reduced semen quality with age and will be at risk of culling in the following years. In order to extend the use of breeder roosters, we drew on the induced molting model of hens and selected 35 Houdan roosters aged 50 wk for induced molting. By comparing the body weight, testicular weight, semen quality, and reproductive performance before and after induced molting, we found that induced molting could restore the body weight and testicular weight to the levels before molting (P > 0.05). At the same time, it significantly improved sperm motility (P < 0.05) and also improved reproductive performance such as fertilization rate and hatching rate. To further reveal the mechanism underlying the effects of induced molting on semen quality and reproductive performance in aged Houdan roosters, we collected testes from 3 periods: 1 d before fasting (F0), 15 d after fasting (F15), and 32 d after recovery feeding (R32) for transcriptome sequencing analysis. A total of 5,671 genes were detected in F0, F15, and R32, and trend analysis of the 5,671 differential genes showed 2 significant trends (profile 5 and profile 2). KEGG enrichment analysis of the genes in the 2 profiles, revealed significantly enriched pathway regulation of actin cytoskeleton. In the regulation of actin cytoskeleton pathway, we found a protein kinase gene (SRC) and a senescence gene (ROCK2). SRC was highly expressed at F15, leading to the phosphorylation of key substrates, which in turn disrupted the Sertoli cell spermatid connection and the spermiogenesis process, resulting in no mature spermatozoa produced from F15, SRC expression was inhibited at R32, the expression level was reduced, and mature spermatozoa reappeared. The senescence gene ROCK2 was highly expressed at F15 compared to F0 and R32, which may have been responsible for inducing senescence atrophy in the testes.

Effects of SLC45A2 and GPNMB on Melanin Deposition Based on Transcriptome Sequencing in Chicken Feather Follicles.

As an essential genetic and economic trait, chicken feather color has long been an important research topic. To further understand the mechanism of melanin deposition associated with coloration in chicken feathers, we selected feather follicle tissues from the neck and wings of chickens with differently colored feathers (yellow, sub-Columbian, and silver) for transcriptome analysis. We focused on genes that were expressed in both the wings and neck and were expressed with the same trends in breeds with two different plumage colors, specifically, SLC45A2, GPNMB, MLPH, TYR, KIT, WNT11, and FZD1. GO and KEGG enrichment analyses showed the DEGs were enriched in melanin-related pathways, such as tyrosine metabolic pathway and melanogenesis, and PPI analysis highlighted the genes SLC45A2 and GPNMB as associated with melanin deposition. Verification experiments in chicken melanocytes demonstrated that these two genes promote melanocyte melanin deposition. These data enrich our knowledge of the mechanisms that regulate chicken feather color.

Immediate and long-term changes in infectious diseases in China at the "First-level-response", "Normalized-control" and "Dynamic-COVID-zero" stages from 2020 to 2022: a multistage interrupted-time-series-analysis.

BACKGROUND: From January 2020 to December 2022, China implemented "First-level-response", "Normalized-control" and "Dynamic-COVID-zero" to block the COVID-19 epidemic; however, the immediate and long-term impact of three strategies on other infectious diseases and the difference in their impact is currently unknown. We aim to provide a more comprehensive understanding of the impact of non-pharmacological interventions (NPIs) on infectious diseases in China. METHODS: We collected data on the monthly case count of infectious diseases in China from January 2015 to July 2022. After considering long-term trends using the Cox-Stuart test, we performed the two ratio Z tests to preliminary analyze the impact of three strategies on infectious diseases. Next, we used a multistage interrupted-time-series analysis fitted by the Poisson regression to evaluate and compare the immediate and long-term impact of three strategies on infectious diseases in China. RESULTS: Compared to before COVID-19, the incidence of almost all infectious diseases decreased immediately at stages 1, 2, and 3; meanwhile, the slope in the incidence of many infectious diseases also decreased at the three stages. However, the slope in the incidence of all sexually transmitted diseases increased at stage 1, the slope in the incidence of all gastrointestinal infectious diseases increased at stage 2, and the slope in the incidence of some diseases such as pertussis, influenza, and brucellosis increased at stage 3. The immediate and long-term limiting effects of "Normalized-control" on respiratory-transmitted diseases were weaker than "First-level-response" and the long-term limiting effects of "Dynamic-COVID-zero" on pertussis, influenza, and hydatid disease were weaker than "Normalized-control". CONCLUSIONS: Three COVID-19 control strategies in China have immediate and long-term limiting effects on many infectious diseases, but there are differences in their limiting effects. Evidence from this study shows that pertussis, influenza, brucellosis, and hydatid disease began to recover at stage 3, and relaxation of NPIs may lead to the resurgence of respiratory-transmitted diseases and vector-borne diseases.