BACKGROUND:Resveratrol (RES), a natural polyphenolic compound, has been reported to regulate cellular differentiation; however, its role in skeletal muscle development in ruminants remains unclear. OBJECTIVES:This study aimed to elucidate the molecular mechanism by which RES regulates myoblast differentiation in goats, with a focus on the role of PROX1 and its downstream signaling pathways. METHODS:Primary myoblasts isolated from a 3-mo-old fetal Nubian goat were used as an in vitro model and treated with 20 μmol/L RES, with untreated cells serving as controls. RNA sequencing was performed to identify differentially expressed genes, and RT-qPCR, molecular docking, as well as gain- and loss-of-function assays were conducted to investigate the role of PROX1 in myogenic differentiation. For in vivo validation, 20 healthy castrated male Nubian goats (180 ± 3 d of age; n = 10/group) were fed either a basal diet (CON) or a basal diet supplemented with 150 mg/kg RES for 120 d. Longissimus dorsi muscle samples were collected at the end of the experiment for subsequent analyses. Myogenic markers and signaling pathways were analyzed, and relative gene expression was calculated using the 2-ΔΔCt method. RESULTS:RNA-seq identified 221 differentially expressed genes after RES treatment, among which PROX1 was significantly upregulated (Log2Fold Change = 1.7, ∼3.25-fold compared with control, P < 0.0001). Molecular docking analysis indicated a stable interaction between RES and PROX1. Both in vitro and in vivo experiments showed that RES significantly increased PROX1 expression by ∼182% and 105%, respectively (P < 0.001). Functional analyses demonstrated that PROX1 overexpression promoted myogenic differentiation, increasing the mRNA expression levels of MyoD, MyoG, and MyHC to 2.70-, 1.75-, and 1.80-fold of control levels, respectively (P < 0.001), whereas MyoD protein expression increased by ∼80% (P < 0.001) and myotube formation was significantly enhanced (P < 0.001). In contrast, PROX1 knockdown markedly inhibited myogenic differentiation, reducing the mRNA expression of MyoD, MyoG, and MyHC by 75%, 48%, and 51%, respectively (P < 0.05), and decreasing MyoD protein expression by ∼43% (P < 0.001). Mechanistically, PROX1 promoted myogenic differentiation through suppression of the NOTCH1/HES1 signaling pathway (P < 0.05). Moreover, RES partially rescued the differentiation impairment induced by PROX1 deficiency through activation of PROX1 (P < 0.05). In vivo validation yielded results consistent with those observed in vitro. CONCLUSIONS:RES promotes myoblast differentiation in goats through PROX1 activation and modulation of NOTCH signaling. These findings identify a PROX1-associated regulatory mechanism in skeletal muscle development in goats.

The adaptation of complex, host-associated microbiomes to environmental perturbations is a critical determinant of ecosystem stability and resilience to climate change, as exemplified in ruminants. While single-microbe RNA sequencing advances community interrogation, complex microbial cell walls severely constrain unbiased single-cell transcriptomic profiling in the rumen. In this study, we developed an optimized 25 min time-resolved enzymatic lysis strategy using smRandom-seq to map the sheep rumen microbiome at single-cell resolution. By profiling 60 748 cells across 21 samples, we captured previously intractable lineages, resolving the transcriptional states of 213 genera and 662 species, achieving a physiologically relevant 0.303% recovery of methanogenic archaea. Unsupervised clustering partitioned the ecosystem into seven cross-species functional clusters, uncovering a spatial coupling between microbial lifestyle and metabolic specialization. Applying this framework to a model of host thermal adaptation demonstrated that host resilience was associated with rapid transcriptional activation of key energy-metabolism clusters. Notably, a lineage-specific metabolic shift toward a glycolytic phenotype in Anaerovibrio lipolyticus contributes to a compensatory "nutritional sparing" effect associated with host resilience. This dataset provides a foundational resource for rumen microbial ecology and establishes a technical framework for dissecting phenotypic plasticity within complex microbiomes.

Livestock farming is a major source of antibiotic resistance in the environment. Although supplementing selenium improves the GI-tract microecosystem and host metabolomes, nano-selenium effects on rumen microbiome and resistome remain limited. Here, multi-omics were performed to classify nano-selenium effects on rumen antibiotic resistance genes (ARGs) reduction, microbiome, metabolites, and host phenotypes on Hainan Black Goats. Increased growth performance, serum growth hormone, and antioxidant parameters by nano-selenium were observed. Nano-selenium significantly decreased the total ARG reads, MLS, and Tetracycline in the rumen. A strong correlation between the rumen resistome and microbiome was found. Nano-selenium increased the abundances of species of Prevotella and Fibrobacter. Moreover, nano-selenium enhanced carbohydrate metabolism and vitamin biosynthesis. Rumen fermentation parameters and metabolites related to carbohydrate utilization and antioxidant capacity were influenced by nano-selenium. Actinobacteria decreased by nano-selenium was associated with major ARGs related to Multidrug and Tetracycline. Structural Equation Modeling revealed that nano-selenium regulated MLS and Tetracycline for ARG reduction, and modulated the microbiome to improve rumen microbiome function. Overall, feeding proper concentrations of nano-selenium effectively reduces ARG pollution in vivo, and improves rumen microecosystem, growth, and antioxidant capacity in goats via microbiome modulation. These findings evidence that nano-selenium could benefit the goat industry, green food, and One Health.

Heat stress (HS) induced by high ambient temperatures markedly disrupts metabolic homeostasis and meat quality development in ruminants, with reduced intramuscular fat (IMF) deposition is considered a major contributor to meat quality deterioration. However, the roles and underlying mechanisms by which inflammatory responses and ferroptosis in the regulation of IMF deposition in Hu sheep under HS conditions remain unclear. This study showed that HS markedly increased the production of pro-inflammatory cytokines, such as TNF-α, IL-6, and IL-8, and induced activation of the NF-κB signaling cascade, thereby suppressing the expression of the anti-ferroptotic enzyme glutathione peroxidase 4 (GPX4). These changes resulted in excessive accumulation of reactive oxygen species, enhanced lipid peroxidation, elevated ferrous iron (Fe2+) levels, ultimately inducing ferroptosis. Further analyses demonstrated that blocking inflammatory responses or inhibiting NF-κB signaling restored GPX4 expression and alleviated ferroptosis, thereby improving fat deposition under HS conditions. Collectively, these findings demonstrate that HS modulates ferroptosis through the “inflammatory cytokine–NF-κB/GPX4 signaling axis,” thereby modulating IMF accumulation in Hu sheep. This study provides new mechanistic insights and potential intervention targets for improving meat quality in sheep under high-temperature conditions.

Hu sheep are highly prized for their tender meat, but heat stress (HS) caused by the high temperature and humidity in southern China severely impacts their performance. This study compared the alleviating effects of Mogroside V (Mog V), epigallocatechin gallate (EGCG), and resveratrol (RES) on HS in Hu sheep. Forty male Hu sheep were randomly divided into a control group and three treatment groups (n = 10), each with a pen. The sheep were housed under HS for 60 days. Body weight, feed conversion ratio (FCR), respiratory rate (RR), and rectal temperature (RT) were monitored. Blood physiological parameters, HSPs, antioxidant enzymes, and inflammatory factors were measured. 16S rRNA sequencing and targeted metabolomics were used to analyze the correlation between rumen microbiota and short-chain fatty acid (SCFA) metabolites. Results showed that all three extracts significantly increased final weight, total weight gain, and daily weight gain, while reducing FCR, RR, and RT. They also decreased HSP70/90, MDA, and the inflammatory factors TNF-α, IL-1β, and IL-6, and increased antioxidant enzyme activity. Microbiome and metabolome analysis revealed that RES increased Verrucomicrobia and Fibrobacterium, promoting propionic and butyric acid production; Mog V enriched Firmicutes and Clostridium succinate, promoting energy metabolism; and EGCG regulated acetate metabolism through Lactobacilli, inhibiting pathogenic bacteria. In summary, all three plant extracts alleviated the physiological damage caused by HS and improved production performance, with Mog V showing the most significant effect and possessing high potential for application.

Super-enhancers (SEs) are critical epigenetic regulators of tissue regeneration, yet their interplay with cellular biomechanics during myogenic differentiation remains unexplored. Here, the TPM1 locus, encoding a core actin-stabilizing protein essential for skeletal muscle regeneration, harbors an evolutionarily conserved SE (TPM1_SE) that may bridge epigenetic control and mechanotransduction. In vitro, TPM1_SE deletion impaired myogenic differentiation and diminished expression of both TPM1 and its circular RNA (circRNA) isoform, CircTPM1. Conditional deletion of TPM1_SE significantly reduce muscle mass and delayed regenerative progression. Mechanistically, TPM1_SE drives expression of linear TPM1 mRNA (mice) and CircTPM1 (bovine) via TEAD4-mediated chromatin looping, coordinating cytoskeletal reorganization during myotube formation. These effects are mediated via activation of the canonical PI3K/AKT signaling pathway through interaction with NKX2.2-a pathway mechanosensitive to cellular tension. Loss of TPM1_SE disrupted NKX2.2-PI3K/AKT signaling. Crucially, CircTPM1 directly bound MYH10, enhancing MYL3-dependent actomyosin assembly, which potentiates cytoskeletal reorganization during myotube formation. Collectively, this findings establish TPM1_SE as an evolutionarily conserved hub integrating epigenetic regulation and biomechanical output. While the murine model underscores its therapeutic potential in muscle regenerative medicine, the bovine CircTPM1-mediated mechanism highlights TPM1_SE as a promising target for genetic improvement of meat quality in livestock.

BackgroundButyric acid deficiency is implicated in polycystic ovary syndrome (PCOS), as evidenced by reduced levels in both clinical and preclinical models. Sodium butyrate (NaBu),a butyric acid substitute, has demonstrated therapeutic potential through gut-brain axis modulation, anti-inflammatory effects, and reproductive function protection. This study investigates NaBu’s mechanistic role in PCOS pathophysiology.MethodsPCOS rats received lipo-coated NaBu diet for three weeks. Systemic and tissue analyses included: serum hormone profiling, lipid metabolism assessment, ovarian/colonic histopathology, Short-chain fatty acids (SCFAs) analysis, and proteomics analysis. Primary granulosa cell cultures with lentiviral transfection elucidated molecular mechanisms. Reproductive performance was evaluated longitudinally.ResultsTreatment with NaBu in PCOS rats resulted in reduced food intake, inhibited weight gain, improved abnormal lipid metabolism, restored estrus cycles and ovulation, lower serum levels of testosterone (T), insulin (INS), and luteinizing hormone (LH), and higher levels of estradiol (E2) and progesterone (P4). Additionally, NaBu treatment improved the morphology of polycystic ovaries, elevated colonic levels of G protein-coupled receptor 41 (GPR41), peptide tyrosine-tyrosine (PYY), and butyric acid, and enhanced reproductive performance in PCOS rats. Proteomic analysis and cell experiments suggested that upregulation of Cytochrome P450 1b1 (Cyp1b1) may play a crucial role in regulating E2 metabolism and P4 production, potentially contributing to the pathogenesis of PCOS and ovarian dysfunction.ConclusionThese findings indicate that NaBu may exert its regulatory effects on appetite and hormone levels in the hypothalamus through the gut-brain-ovary axis, modulating the expression of ovarian steroidogenic factors, thereby improving follicular development and granulosa cell function, and enhancing reproductive performance.

The establishment and maintenance of spermatogenesis is a complex process involving a vast of regulatory pathways. There is growing evidence revealing that long noncoding RNAs (lncRNA) play important roles in regulating testicular development and spermatogenesis in a stage-specific way. However, our understanding of how lncRNA regulates testicular development and spermatogenesis in black goats is quite limited. In the current study, we screened the transcriptomes (lncRNA and mRNA) of testicular from Guangxi black goats before puberty (3 days old, D3; 30 days old, D30), puberty (90 days old, D90) and postpuberty (180 days old, D180), in order to identify the lncRNA interaction with mRNAs contributes to goat spermatogenesis. The RNA-sequencing (RNA-seq) analysis showed that there were 1211, 12,180, 834 differential lncRNAs and 1196, 8838,269 differential mRNAs at the ages of D30 vs. D3, D90 vs. D30, and D180 vs. D90. The lncRNAs showed the most significantly changes from D30 to D90, which indicated that D90 was a key node of lncRNAs participated in the regulation of testicular development and spermatogenesis in black goat. According to functional enrichment analysis of GO and KEGG, we found that differentially expressed lncRNAs (DE lncRNAs) and their target genes regulated spermatogenesis through signal pathways including MAPK, Ras, and PI3K-Akt. Using cis- and trans-acting, 39 DE lncRNAs-targeted genes were found to be enriched for male reproduction. Of these, LOC108635509, which specific expressed in testis and upregulated the expression levels at D90, was found participated in the regulation of testicular development through promoting the proliferation of Sertoli cells (SCs). Overall, this study provides new insight into the regulatory mechanisms that support spermatogenesis and testicular development in black goats.

Cryopreservation is a common assisted reproductive technology in goat breeding, but it often impairs sperm quality and fertilizing ability. This study aimed to explore the effects of cryopreservation on sperm quality and protein abundance profiles in Nubian goat spermatozoa using TMT-based quantitative proteomics. Semen from six healthy adult bucks was divided into fresh and frozen-thawed groups. Key sperm quality parameters, including total motility, membrane integrity, acrosomal integrity, and abnormality rates, were evaluated. TMT-labeled proteomic analysis was performed, followed by GO, KEGG, and PPI network analyses. Results showed that cryopreservation significantly reduced total motility, membrane and acrosomal integrity, while increasing abnormality rates (P < 0.0001). A total of 204 differentially abundant proteins (DAPs) were identified, including 108 upregulated and 96 downregulated proteins. Functional enrichment revealed that these DAPs were mainly involved in glycolysis, cytoskeleton organization, lysosomal function, and oxidative stress. PPI analysis identified GAPDHS, ODF2, and ALB as key proteins potentially regulating sperm cryoinjury. This study provides new insights into the molecular mechanisms of sperm cryodamage in goats and suggests candidate biomarkers for improving cryopreservation strategies.

The growth and maturation of Sertoli cells (SCs) are important part of testicular development and miRNAs are considered as novel regulatory molecules involved in it. Here we systematically screened and analyzed the key miRNAs participating in testicular development of black goat, as well as identified underlying mechanism of candidate mRNAs that contributed to spermatogenesis. The miRNA transcriptional profiles of testicular tissues at 3 days old (D3), 30 days old (D30), 90 days old (D90), and 180 days old (D180) were constructed and comparative analyzed. Results showed that the most differentially expressed (DE) miRNAs were found between the testicular tissues of D30 and D90 black goats. Moreover, the predicted target genes of DE miRNAs were mainly enriched in biological processes including cell proliferation, cell composition and enriched in signaling pathways including p53, FoxO, and PI3K-Akt. The top one DE miRNA (miR-34c-5p), which significantly highly expressed in the testis of D90 when compared to that of D30, was mainly located within SCs and targeted to IGF1R. By performing miR-34c-5p overexpression and RNA interference, we found that the function of miR-34c-5p in SCs was inhibited cell proliferation, increased apoptosis rate, and significantly reduced the expression of growth factors (CXCL12, BMP4, GDNF, and IGF1). In summary, our study suggests that miR-34c-5p can serve as a potential target for regulation of testicular development and a reference marker of puberty applied to black goat genetic breeding.

As an indigenous goat breed unique to southern China, Leizhou Black Goats (LZBGs) are highly valued for their rapid growth, high reproductive performance, and superior meat quality. However, their offspring frequently exhibit symptoms of muscle atrophy and malnutrition, suggesting potential genetic defects underlying these adverse phenotypes. As a unique extracellular matrix component, collagen Q (COLQ) is specifically enriched within the synaptic basal lamina at vertebrate neuromuscular junctions (NMJs), where it anchors acetylcholinesterase (AChE) to facilitate efficient acetylcholine hydrolysis, ensuring precise neuromuscular signaling. The current investigation sought to characterize the spectrum of genetic polymorphisms within the COLQ gene and assess their correlation with key production traits, including growth performance and meat quality parameters, in the LZBG population. Previously, through whole-genome sequencing and transcriptome sequencing analyses of an LZBG population, we identified four SNPs in the COLQ gene, namely, two missense mutations (SNP1: p.238A/S and SNP3: p.47G/S), one intronic variant (SNP2), and one synonymous mutation (SNP4: p.101P/P). Population genetic analysis revealed strong linkage disequilibrium between SNP1 and SNP2. Computational modeling of protein structures predicted that the identified missense mutations may lead to alterations in protein conformation. Association analyses demonstrated significant correlations of SNP1 and SNP3 with growth and meat quality traits (p < 0.05), where SNP3 reduced COLQ expression by 0.64-fold in homozygotes. Association analysis revealed that both SNP1 and SNP3 showed significant correlations with growth and meat quality traits in LZBGs (p < 0.05). Notably, SNP3 (p.47G/S) was found to regulate COLQ gene expression, reducing its levels by 0.64-fold in homozygous individuals, suggesting its potential as a genetic marker for selecting goats with superior growth performance and muscular development characteristics. The identified genetic variants establish a foundation for marker-assisted selection in LZBG breeding programs with particular relevance to growth performance enhancement, while also advancing the understanding of COLQ’s functional mechanisms in muscle development.

Climate change poses an increasing threat to livestock reproduction, with heat stress (HS) known to significantly impair ovarian function. This study aimed to elucidate the impact of HS on ovarian function and circRNA expression profiles in Hu sheep. Twelve ewes were randomly assigned to a control (Con, n = 6) or HS group (n = 6) and exposed to different temperatures for 68 days. Compared with the Con group, HS significantly increased the respiratory rate (108.33 ± 3.72 vs. 63.58 ± 2.42 breaths/min), pulse rate (121.17 ± 3.98 vs. 78.08 ± 3.31 beats/min), and rectal temperature (40.17 ± 0.14 °C vs. 39.02 ± 0.21 °C; p < 0.05). Concurrently, serum antioxidant levels were markedly decreased, including total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), and glutathione peroxidase (GSH-Px) (p < 0.05). Histological analysis revealed a significant reduction in the numbers of primordial, primary, secondary, and mature follicles, alongside an increase in antral follicles (p < 0.05). TUNEL staining demonstrated enhanced granulosa cell apoptosis (p < 0.05), accompanied by the upregulation of pro-apoptotic genes Bax and Caspase-3 and downregulation of the anti-apoptotic gene Bcl-2, as confirmed by qPCR (p < 0.05). CircRNA sequencing identified 152 differentially expressed circRNAs (120 upregulated, 32 downregulated), and enrichment analyses indicated their involvement in apoptosis, mitophagy, and the FoxO signaling pathway. Collectively, these findings demonstrate that HS impairs ovarian physiology and antioxidant defense, induces follicular damage and cell apoptosis, and alters circRNA expression profiles, providing new insights into the molecular mechanisms underlying HS-induced reproductive dysfunction in Hu sheep.

Heat stress (HS) is a major environmental factor negatively impacting the reproductive performance of livestock. This study investigates the molecular mechanisms of heat stress on the hypothalamic–pituitary–ovarian (HPO) axis in Hu sheep. A heat-stressed animal model was established, and high-throughput RNA sequencing (RNA-seq) was employed to analyze gene expression in the hypothalamus, pituitary, and ovarian tissues of both control and heat-stressed groups. The results revealed significant changes in estrus behavior, hormone secretion, and reproductive health in heat-stressed sheep, with a shortened estrus duration, prolonged estrous cycles, and decreased levels of FSH, LH, E2, and P4. A total of 520, 649, and 482 differentially expressed genes (DEGs) were identified in the hypothalamus, pituitary, and ovary, respectively. The DEGs were enriched in pathways related to hormone secretion, neurotransmission, cell proliferation, and immune response, with significant involvement of the p53 and cAMP signaling pathways. Tissue-specific responses to heat stress were observed, with distinct regulatory roles in each organ, including GPCR activity and cytokine signaling in the hypothalamus, calcium-regulated exocytosis in the pituitary, and cilium assembly and ATP binding in the ovary. Key genes such as SYN3, RPH3A, and IGFBP2 were identified as central to the coordinated regulation of the HPO axis. These findings provide new insights into the molecular basis of heat stress-induced impairments in reproductive function—manifested by altered estrous behavior, reduced hormone secretion (FSH, LH, E2, and P4), and disrupted gene expression in the hypothalamic–pituitary–ovarian (HPO) axis—and offer potential targets for improving heat tolerance and reproductive regulation in sheep.

With the rapid development of intensive animal husbandry in the livestock industry, large quantities of manure waste containing phytate phosphorus are being generated. Phytase can effectively solve the problem of high phosphorus pollution in the feces of monogastric animals. Enviropig, which produces phytase in the salivary glands and secretes the enzyme in the saliva, were first generated in 1999. However, phytase is easily inactivated during digestion. To address this problem, cleavage-resistant phytase transgenic pigs were generated using handmade cloning in this study. Transgene construction was improved and three cell lines carrying Cafp were obtained. In total, 810 blastocysts were generated and 712 good-quality were transferred into six recipients. Fourteen piglets were born, of which six survived after weaning. Polymerase chain reaction and sequencing results showed that seven (three live and four dead) of the fourteen piglets carried Cafp. Phytase activity in the saliva of the six live cloned pigs was tested at four months of age, and only one pig had 0.155 FTU/mL enzyme activity. The other five pigs may not have been activated in the transgenic parotid gland. Among all the transgenic pigs, the highest phosphorus digestion rate was 59.2% of intake, representing a 25.4% decrease in fecal emission compared to the average of controls. Immunohistochemical results on the three Cafp-positive pigs that died after six months of age showed that the transgene was only expressed in parotid glands, confirming tissue-specific gene expression. In conclusion, cleavage-resistant phytase transgenic pigs were successfully produced through handmade cloning. The cloned pigs offer a unique biological approach to managing phosphorus nutrition and environmental pollution in animal husbandry.

Increases in litter size, which are influenced by ovulation, are responsible for between 74% and 96% of the economic value of genetic progress, which influences selection. For the selection and breeding of highly prolific goats, genetic mechanisms underlying variations in litter size should be elucidated. Here, we used single-nucleus RNA sequencing to analyze 44,605 single nuclei from the ovaries of polytocous and monotocous goats during the follicular phase. Utilizing known reference marker genes, we identified 10 ovarian cell types characterized by distinct gene expression profiles, transcription factor networks, and reciprocal interaction signatures. An in-depth analysis of the granulosa cells revealed three subtypes exhibiting distinct gene expression patterns and dynamic regulatory mechanisms. Further investigation of cell-type-specific prolificacy-associated transcriptional changes elucidated that “downregulation of apoptosis”, “increased anabolism”, and “upstream responsiveness to hormonal stimulation” are associated with prolificacy. This study provides a comprehensive understanding of the cell-type-specific mechanisms and regulatory networks in the goat ovary, providing insights into the molecular mechanisms underlying goat prolificacy. These findings establish a vital foundation for furthering understanding of the molecular mechanisms governing folliculogenesis and for improving the litter size in goats via molecular design breeding.

This research aims at uncovering the effects and investigating the molecular mechanisms of dietary resveratrol (RES) supplementation on antioxidant capacity and meat quality of pigs. In this study, 20 mu M RES could activate the KEAP1-NRF2 antioxidant defense pathway in response to oxidative stress in porcine skeletal muscle satellite cells was firstly found. Then, twenty-four healthy crossbred castrated boars were allocated to 4 treatments that were fed with a basal diet (control) and a basal diet supplemented with 200 mg, 400 mg or 600 mg RES per Kilogram (kg) of feed for 41 days, respectively. 400 and 600 mg/kg RES-supplemented diet can effectively improve the meat quality traits and activities of antioxidizing enzymes via the KEAP1-NRF2 signaling pathway of pigs. The molecular dynamic simulation further revealed that RES could directly binding to KEAP1 to reduce the tightness of KEAP1-NRF2 protein-protein interaction. More importantly, dietary supplementation of RES also improves antioxidant capacity through a series of KEAP1-NRF2 pathway-related lncRNAs were found by RNA sequencing (RNA-seq). Altogether, this study demonstrated that RES improves meat quality traits by effectively increasing antioxidant levels via the lncRNA-KEAP1-NRF2 axis in vivo and/or in vitro. These results provide new insights into the molecular mechanisms by which RES, as a nutritional agent, regulates antioxidant capacity and improves meat quality in pigs.

The heat stress (HS) induced by high temperatures can result in oxidative damage to muscles, thereby compromising both muscle growth and immune function within the organism. Mitophagy serves as a pivotal pathway in alleviating excessive ROS production and subsequent oxidative damage. However, the potential role of epigallocatechin-3-gallate (EGCG), a natural antioxidant found in tea, in mitophagy under HS remains unexplored. Here, we present evidence of EGCG mitigating the oxidative-redox imbalance in porcine skeletal muscles induced by HS involving the antioxidant enzyme system mediated by the Keap1/Nrf2 pathway and mitophagy mediated by the PINK1/Parkin pathway. Importantly, we identified phosphate mutase 5 (PGAM5) for the first time as a key protein modulated by EGCG under HS conditions, regulating mitophagy. Inhibition of PGAM5 significantly attenuated the activation of mitophagy by EGCG. Molecular docking and dynamics simulations further suggested that EGCG directly binds to Keap1, disrupting the Keap1-PGAM5 protein interaction and thus promoting the release of PGAM5 and subsequently activating mitophagy. In summary, this study represents the first discovery of EGCG directly targeting Keap1/PGAM5-mediated mitophagy, which serves as a potential functional supplement for regulating the antioxidant capacity in pigs.

MiR-486-5p has been identified as a crucial regulator of the PI3K/AKT signalling pathway, which plays a significant role in skeletal muscle development. Its host gene, sANK1, is also essential for skeletal muscle development. However, the understanding of porcine miR-486-5p and sANK1 has been limited. In this study, PCR analyses revealed a positive correlation between the expression of miR-486-5p and sANK1 in the longissimus dorsi muscle of the Bama mini-pig and Landrace-pig, as well as during myoblast differentiation. Furthermore, the expression of miR-486-5p/sANK1 was higher in the Bama mini-pig compared to the Landrace-pig. There was a total of 18 single nucleotide polymorphisms (SNP) present in the sANK1 promoter region. Among these SNPs, 14 of them resulted in alterations in transcription factor binding sites (TFBs). Additionally, the promoter fluorescence assay demonstrated that the activity of the sANK1 promoter derived from the Bama mini-pig was significantly higher compared to Landrace-pig. It is worth noting that ten regulatory SNPs have the potential to influence the activity of the sANK1 promoter. A nuclear mutation A-G located at position − 401 (relative to the transcription start site) in the Bama mini-pig was identified, which creates a putative TFB motif for MyoD. The findings presented in this study offer fundamental molecular knowledge and expression patterns of miR-486-5p/sANK1, which can be valuable for gaining a deeper understanding of the gene’s involvement in porcine skeletal muscle development, and meat quality.

Obesity has emerged as a prominent global health concern, with heat stress posing a significant challenge to both human health and animal well-being. Despite a growing interest in environmental determinants of obesity, very few studies have examined the associations between heat stress-related environmental factors and adiposity. Consequently, there exists a clear need to understand the molecular mechanisms underlying the obesogenic effects of heat stress and to formulate preventive strategies. This study focused on culturing porcine subcutaneous preadipocytes at 41.5 ℃ to induce heat stress, revealing that this stressor triggered apoptosis and fat deposition. Analysis demonstrated an upregulation in the expression of HSP70, BAX, adipogenesis-related genes (PPARγ, AP2, CEBPα and FAS), the p-AMPK/AMPK ratio and SIRT1, PGC-1α in the heat stress group compared to the control group (P < 0.05). Conversely, the expression of lipid lysis-related genes (ATGL, HSL and LPL) and Bcl-2 decreased in the heat stress group compared to the control group (P < 0.05). Furthermore, subsequent activator and/or inhibitor experiments validated that heat stress modulated HSP70 and AMPK signalling pathways to enhance lipogenesis and inhibit lipolysis in porcine subcutaneous preadipocytes. Importantly, this study reveals, for the first time, that EGCG mitigates heat-stress-induced fat deposition by targeting HSP70 through the activation of AMPK-SIRT1-PGC-1α in porcine subcutaneous preadipocytes. These findings elucidate the molecular mechanisms contributing to heat stress-induced obesity and provide a foundation for the potential clinical utilisation of EGCG as a preventive measure against both heat stress and obesity.

This study examined the effect of dietary supplementation of nano-selenium (nano-Se) on the average daily gain (ADG), fecal bacteria community, and concentrations of fecal minerals and volatile fatty acids in feedlot Hainan black goats. Eighteen goats (18.6 ± 0.69 kg) were divided randomly into three groups, with each group receiving a different level of supplementary nano-Se (n = six goats per treatment) as follows: (1) 0.0 mg (CON); (2) 0.2 mg; and (3) 0.4 mg nano-Se/kg dry matter intake (DMI). The final body weight (p = 0.012) and ADG increased linearly (p < 0.01), whereas the ratio of DMI to ADG decreased linearly (p < 0.01) with increasing dietary nano-Se levels. Fecal concentrations of Se increased linearly (p < 0.001), whereas Cu (p < 0.01), Zn (p = 0.020), and Fe (p = 0.010) decreased linearly with increasing dietary nano-Se levels. The relative abundances of Treponema (p = 0.046), norank_f__norank_o__Clostridia_UCG-014 (p < 0.01), norank_ f_norank_o__RF39 (p < 0.01), Eubacterium_siraeum_group (p < 0.001), and Family_XIII_AD3011_group (p = 0.040) increased linearly, and unclassified_f__Lachnospiraceae (p < 0.001), Rikenellaceae_RC9_gut_group (p < 0.01), Eubacterium_ruminantium_group (p = 0.021), and Prevotella (p < 0.001) decreased linearly with increasing dietary nano-Se levels. It was concluded that supplementary nano-Se could improve ADG and reduce the DMI to ADG ratio and fecal heavy metals by altering the bacterial community in feedlot goats. We recommend a dietary supplementation of approximately 0.4 mg nano-Se/kg DM for feedlot Hainan black goats, but further research is warranted to determine the precise dose and the possible contamination risks of Se.