Turtle peptide and its derivative peptide ameliorated DSS-induced ulcerative colitis by inhibiting inflammation and modulating the composition of the gut microbiota.

Ulcerative colitis (UC) is a recurrent intestinal disease with an increasing incidence worldwide that seriously affects the life of patients. Turtle peptide (TP) is a bioactive peptide extracted from turtles that has anti-inflammatory, antioxidant and anti-aging properties. However, studies investigating the effect of TP on the progression of UC are lacking. The aim of this study was to investigate effects and underlying mechanisms of TP and its derivative peptide GPAGPIGPV (GP-9) in alleviating UC in mice. The results showed that 500 mg/kg TP treatment significantly ameliorated colitis symptoms and oxidative stress in UC mice. TP alleviated intestinal barrier damage in UC mice by promoting mucosal repair and increasing the expression of tight junction proteins (ZO1, occludin and claudin-1). TP also modulated the composition of the gut microbiota by increasing the abundance of the beneficial bacteria Anaerotignum, Prevotellaceae_UCG-001, Alistipes, and Lachno-spiraceae_NK4A136_group and decreasing the abundance of the harmful bacteria Prevotella_9 and Parasutterella. Furthermore, we characterized the peptide composition of TP and found that GP-9 ameliorated the symptoms of dextran sodium sulfate (DSS)-induced colitis in mice by inhibiting the TLR4/NF-κB signaling pathway. In conclusion, TP and its derivative peptides ameliorated DSS-induced ulcerative colitis by inhibiting the expression of inflammatory factors and modulating the composition of the intestinal microbiota; this study provides a theoretical basis for the application of TP and its derivative peptides for their anti-inflammatory activity.

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Antibiotic resistance genes (ARGs) have attracted widespread attention as a new global pollutant, mainly due to the abuse of antibiotics. To investigate the diversity of ARGs in three rodent species, we used metagenomic sequencing analysis to analyze the diversity of antibiotic resistance genes of 17 individuals of Apodemus peninsulae and 17 individuals of Myodes rufocanus collected from Mudanfeng, and nine individuals of Apodemus agrarius collected from Sandaoguan. A total of 19 types and 248 subclasses of ARGs were detected in the three rodent species. Seven ARGs showed significant difference and five ARGs showed extremely significant difference between M. rufocanus and A. agrarius. Seven ARGs showed significant difference and four ARGs showed extremely significant difference between A. peninsulae and A. agrarius. Four ARGs showed significant difference and five ARGs showed extremely significant difference between M. rufocanus and A. peninsulae. ARGs showing high abundance in three rodents were macrolides, lincoamides, tetracyclines, and ß-lactams. ARGs were widely distributed in the three rodent species. The significant differences in ARGs among different species might be due to the different distribution areas and their diet differentiation. The study could provide a basis for further studies of ARGs in mice and improve the understanding of the harm of ARGs transmission.

Fabrication and characterization of shellac nanofibers with colon-targeted delivery of quercetin and its anticancer activity.

In this study, the feasibility of shellac nanofibers as carrier system for colonic delivery of quercetin was evaluated. Firstly, the nanofibers without and with different amounts (2.5 %, 5.0 %, and 7.5 %) of quercetin were fabricated using pure shellac as a carrier by electrospinning. The morphology of nanofibers was bead-shape confirmed by SEM. FTIR, XRD, and DSC analysis showed that quercetin was encapsulated into shellac nanofibers, forming an amorphous complex. The molecular docking simulation indicated quercetin bound well to shellac through hydrogen bonding and van der Waals forces. These nanofibers had higher thermal stability than pure quercetin, and their surface wettability exhibited a pH-responsive behavior. The loading capacity of quercetin varied from 2.25 % to 6.84 % with the increased amount of quercetin, and it affected the stability of nanofibers in food simulants by measuring the release profiles of quercetin. The shellac nanofibers had high gastrointestinal stability, with a minimum quercetin release of 16.87 % in simulated digestive fluids, while the remaining quercetin was delivered to the colon and was released gradually. Moreover, the nanofibers exerted enhanced anticancer activity against HCT-116 cells by arresting cell cycle in G0/G1 phase and inducing cell apoptosis. Overall, shellac nanofibers are promising materials for colon-targeted delivery of active compounds.

The potential crosstalk genes and molecular mechanisms between glioblastoma and periodontitis.

Despite clinical and epidemiological evidence suggestive of a link between glioblastoma (GBM) and periodontitis (PD), the shared mechanisms of gene regulation remain elusive. In this study, we identify differentially expressed genes (DEGs) that overlap between the GEO datasets GSE4290 [GBM] and GSE10334 [PD]. Functional enrichment analysis was conducted, and key modules were identified using protein-protein interaction (PPI) network and weighted gene co-expression network analysis (WGCNA). The expression levels of CXCR4, LY96, and C3 were found to be significantly elevated in both the test dataset and external validation dataset, making them key crosstalk genes. Additionally, immune cell landscape analysis revealed elevated expression levels of multiple immune cells in GBM and PD compared to controls, with the key crosstalk genes negatively associated with Macrophages M2. FLI1 was identified as a potential key transcription factor (TF) regulating the three key crosstalk genes, with increased expression in the full dataset. These findings contribute to our understanding of the immune and inflammatory aspects of the comorbidity mechanism between GBM and PD.

CGA alleviates LPS-induced inflammation and milk fat reduction in BMECs through the NF-κB signaling pathway.

Mastitis is an easy clinical disease in dairy cows, which seriously affects the milk yield and quality of dairy cows. Chlorogenic acid (CGA), a polyphenolic substance, is abundant in Eucommia ulmoides leaves and has anti-inflammatory and anti-oxidative stress effects. Here, we explore whether CGA attenuated lipopolysaccharide (LPS)-induced inflammation and decreased milk fat in bovine mammary epithelial cells (BMECs). 10 µg/mL LPS was used to induce mastitis in BMECs. QRT-PCR, Western blotting, oil red O staining, and triglyceride (TG) assay were used to examine the effects of CGA on BMECs, including inflammatory response, oxidative stress response, and milk fat synthesis. The results showed that CGA repaired LPS-induced inflammation in BMECs. The expression of IL-6, IL-8, TNF-α, IL-1ß, and iNOS was decreased, and the expression levels of CHOP, XCT, NRF2, and HO-1 were increased, which reduced the oxidative stress level of cells and alleviated the reduction of milk fat synthesis. In addition, the regulation of P65 phosphorylation by CGA suggests that CGA may exert its anti-inflammatory and anti-oxidative effects through the NF-κB signaling pathway. Our study showed that CGA attenuated LPS-induced inflammation and oxidative stress, and restored the decrease in milk fat content in BMECs by regulating the NF-κB signaling pathway.

EGF-driven EGFR/miR-27b-3p/FOXO1 promotes rat FSH synthesis and secretion.

The adenopituitary secretes follicle-stimulating hormone (FSH), which plays a crucial role in regulating the growth, development, and reproductive functions of organisms. Investigating the process of FSH synthesis and secretion can offer valuable insights into potential areas of focus for reproductive research. Epidermal growth factor (EGF) is a significant paracrine/autocrine factor within the body, and studies have demonstrated its ability to stimulate FSH secretion in animals. However, the precise mechanisms that regulate this action are still poorly understood. In this research, in vivo and in vitro experiments showed that the activation of epidermal growth factor receptor (EGFR) by EGF induces the upregulation of miR-27b-3p and that miR-27b-3p targets and inhibits Foxo1 mRNA expression, resulting in increased FSH synthesis and secretion. In summary, this study elucidates the precise molecular mechanism through which EGF governs the synthesis and secretion of FSH via the EGFR/miR-27b-3p/FOXO1 pathway.

Phase-equilibrium characteristics of methane hydrate in clay mineral suspensions: Differential scanning calorimetry experiments and density functional theory studies.

The investigation of methane hydrate equilibrium conditions is crucial for comprehending the occurrence of methane hydrate in marine sediments. In this study, the liquid-hydrate-vapor equilibrium condition of methane hydrate in montmorillonite and kaolinite suspensions in the presence of glycine was investigated through differential scanning calorimetry experiments. The results indicated that glycine inhibited the phase equilibrium of methane hydrate. The phase equilibrium conditions of methane hydrate in kaolinite suspension closely resembled those in pure water. In contrast, calcium montmorillonite hindered the phase equilibrium of methane hydrate owing to the presence of Ca2+. The phase equilibrium conditions of methane hydrate in kaolinite suspension with the addition of glycine were similar to those in glycine solution. The inhibitory effect of calcium montmorillonite on the phase equilibrium condition of methane hydrate intensified with the addition of glycine. Furthermore, density functional theory simulations indicated that glycine significantly reduced the binding energy between montmorillonite layers and Ca2+, potentially mitigating the inhibitory effect of Ca2+ on methane hydrate formation under suitable glycine concentrations. The diverse equilibrium conditions of methane hydrate, influenced by the types of clay minerals, salt ions, and organic matters, may play a critical role in the formation and occurrence of natural gas hydrates in marine environments, warranting exploration in future studies.

Fimbrin associated with Pmk1 to regulate the actin assembly during Magnaporthe oryzae hyphal growth and infection.

The dynamic assembly of the actin cytoskeleton is vital for Magnaporthe oryzae development and host infection. The actin-related protein MoFim1 is a key factor for organizing the M. oryzae actin cytoskeleton. Currently, how MoFim1 is regulated in M. oryzae to precisely rearrange the actin cytoskeleton is unclear. In this study, we found that MoFim1 associates with the M. oryzae mitogen-activated protein (MAP) kinase Pmk1 to regulate actin assembly. MoFim1 directly interacted with Pmk1, and the phosphorylation level of MoFim1 was decreased in Δpmk1, which led to a change in the subcellular distribution of MoFim1 in the hyphae of Δpmk1. Moreover, the actin cytoskeleton was aberrantly organized at the hyphal tip in the Δpmk1, which was similar to what was observed in the Δmofim1 during hyphal growth. Furthermore, phosphorylation analysis revealed that Pmk1 could phosphorylate MoFim1 at serine 94. Loss of phosphorylation of MoFim1 at serine 94 decreased actin bundling activity. Additionally, the expression of the site mutant of MoFim1 S94D (in which serine 94 was replaced with aspartate to mimic phosphorylation) in Δpmk1 could reverse the defects in actin organization and hyphal growth in Δpmk1. It also partially rescues the formation of appressorium failure in Δpmk1. Taken together, these findings suggest a regulatory mechanism in which Pmk1 phosphorylates MoFim1 to regulate the assembly of the actin cytoskeleton during hyphal development and pathogenesis.

Initial Upper Palaeolithic material culture by 45,000 years ago at Shiyu in northern China.

The geographic expansion of Homo sapiens populations into southeastern Europe occurred by ∼47,000 years ago (∼47 ka), marked by Initial Upper Palaeolithic (IUP) technology. H. sapiens was present in western Siberia by ∼45 ka, and IUP industries indicate early entries by ∼50 ka in the Russian Altai and 46-45 ka in northern Mongolia. H. sapiens was in northeastern Asia by ∼40 ka, with a single IUP site in China dating to 43-41 ka. Here we describe an IUP assemblage from Shiyu in northern China, dating to ∼45 ka. Shiyu contains a stone tool assemblage produced by Levallois and Volumetric Blade Reduction methods, the long-distance transfer of obsidian from sources in China and the Russian Far East (800-1,000 km away), increased hunting skills denoted by the selective culling of adult equids and the recovery of tanged and hafted projectile points with evidence of impact fractures, and the presence of a worked bone tool and a shaped graphite disc. Shiyu exhibits a set of advanced cultural behaviours, and together with the recovery of a now-lost human cranial bone, the record supports an expansion of H. sapiens into eastern Asia by about 45 ka.

MSI2 Modulates Unsaturated Fatty Acid Metabolism by Binding FASN in Bovine Mammary Epithelial Cells.

The regulation of fatty acid metabolism is crucial for milk flavor and quality. Therefore, it is important to explore the genes that play a role in fatty acid metabolism and their mechanisms of action. The RNA-binding protein Musashi2 (MSI2) is involved in the regulation of numerous biological processes and plays a regulatory role in post-transcriptional translation. However, its role in the mammary glands of dairy cows has not been reported. The present study examined MSI2 expression in mammary glands from lactating and dry milk cows. Experimental results in bovine mammary epithelial cells (BMECs) showed that MSI2 was negatively correlated with the ability to synthesize milk fat and that MSI2 decreased the content of unsaturated fatty acids (UFAs) in BMECs. Silencing of Msi2 increased triglyceride accumulation in BMECs and increased the proportion of UFAs. MSI2 affects TAG synthesis and milk fat synthesis by regulating fatty acid synthase (FASN). In addition, RNA immunoprecipitation experiments in BMECs demonstrated for the first time that MSI2 can bind to the 3'-UTR of FASN mRNA to exert a regulatory effect. In conclusion, MSI2 affects milk fat synthesis and fatty acid metabolism by regulating the triglyceride synthesis and UFA content through binding FASN.

Agaricus blazei Polysaccharide Alleviates DSS-Induced Colitis in Mice by Modulating Intestinal Barrier and Remodeling Metabolism.

Ulcerative colitis (UC) is a chronic noninfectious intestinal disease that severely affects patients' quality of life. Agaricus blazei Murrill polysaccharide (ABP) is an effective active ingredient extracted from Agaricus blazei Murrill (ABM). It has good efficacy in inhibiting tumor cell growth, lowering blood pressure, and improving atherosclerosis. However, its effect on colitis is unclear. The aim of this study was to analyze the protective effects and potential mechanisms of ABP against dextran sulfate sodium (DSS)-induced acute colitis in mice. The results showed that dietary supplementation with ABP significantly alleviated DSS-induced colitis symptoms, inflammatory responses, and oxidative stress. Meanwhile, ABP intervention was able to maintain the integrity of the intestinal mechanical barrier by promoting the expression of ZO-1 and Occludin tight junction proteins and facilitating mucus secretion. Moreover, 16S rRNA sequencing results suggested that ABP intervention was able to alleviate DSS-induced gut microbiota disruption, and nontargeted metabolomics results indicated that ABP was able to remodel metabolism. In conclusion, these results demonstrate that dietary supplementation with ABP alleviated DSS-induced acute colitis by maintaining intestinal barrier integrity and remodeling metabolism. These results improve our understanding of ABP function and provide a theoretical basis for the use of dietary supplementation with ABP for the prevention of ulcerative colitis.

miR-302d Targeting of CDKN1A Regulates DNA Damage and Steroid Hormone Secretion in Bovine Cumulus Cells.

(1) Background: DNA damage in cumulus cells hinders oocyte maturation and affects steroid hormone secretion. It is crucial to identify the key factors that regulate cellular DNA damage and steroid hormone secretion. (2) Methods: Treatment of bovine cumulus cells with bleomycin to induce DNA damage. The effects of DNA damage on cell biology were determined by detecting changes in DNA damage degree, cell cycle, viability, apoptosis, and steroid hormones. It was verified that mir-302d targeted regulation of CDKN1A expression, and then affected DNA damage and steroid hormone secretion in cumulus cells. (3) Results: Bleomycin induced increased DNA damage, decreased G1-phase cells, increased S-phase cells, inhibited proliferation, promoted apoptosis, affected E2 and P4 secretion, increased CDKN1A expression, and decreased miR-302d expression. Knockdown of CDKN1A reduced DNA damage, increased G1-phase cells, decreased G2-phase cells, promoted proliferation, inhibited apoptosis, increased E2 and P4 secretion, and increased the expression of BRCA1, MRE11, ATM, CDK1, CDK2, CCNE2, STAR, CYP11A1, and HSD3B1. The expression of RAD51, CCND1, p53, and FAS was decreased. Overexpression of CDKN1A resulted in the opposite results. miR-302d targets CDKN1A expression to regulate DNA damage and then affects the cell cycle, proliferation, apoptosis, steroid hormone secretion, and the expression of related genes. (4) Conclusions: miR-302d and CDKN1A were candidate molecular markers for the diagnosis of DNA damage in bovine cumulus cells.

Oat Peptides Alleviate Dextran Sulfate Sodium Salt-Induced Colitis by Maintaining the Intestinal Barrier and Modulating the Keap1-Nrf2 Axis.

The prevalence of inflammatory bowel disease (IBD) is progressively rising each year, emphasizing the significance of implementing rational dietary interventions for disease prevention. Oats, being a staple agricultural product, are abundant in protein content. This study aimed to investigate the protective effects and underlying mechanisms of oat peptides (OPs) in a mouse model of acute colitis induced by dextran sulfate sodium salt (DSS) and a Caco-2 cell model. The findings demonstrated that intervention with OPs effectively mitigated the symptoms associated with DSS-induced colitis. The physicochemical characterization analysis demonstrated that the molecular weight of the OPs was predominantly below 5 kDa, with a predominant composition of 266 peptides. This study provides further evidence of the regulatory impact of OPs on the Keap1-Nrf2 signaling axis and elucidates the potential role of WGVGVRAERDA as the primary bioactive peptide responsible for the functional effects of OPs. Ultimately, the results of this investigation demonstrate that OPs effectively mitigate DSS-induced colitis by preserving the integrity of the intestinal barrier and modulating the Keap1-Nrf2 axis. Consequently, these findings establish a theoretical foundation for the utilization of OPs as dietary supplements to prevent the onset of IBD.

Sea Cucumber Peptides Ameliorate DSS-Induced Ulcerative Colitis: The Role of the Gut Microbiota, the Intestinal Barrier, and Macrophage Polarization.

The incidence of ulcerative colitis (UC) is increasing annually. There are few treatments for UC patients, and some drugs have serious side effects. Sea cucumber peptide (SCP) has anti-inflammatory, antioxidant and other biological activities, and various sea cucumber species are in pharmaceutical development. However, relevant studies on the effects of SCP on UC progression are still lacking. In this study, a mouse model of acute colitis was induced by 3% dextran sulfate (DSS), and the effect of 500 mg/kg SCP on colitis was investigated. The results showed that SCP can alleviate DSS-induced colon damage and intestinal barrier damage. SCP significantly inhibited the expression of inflammatory factors and oxidative stress in UC mice. SCP reversed the intestinal microbiota dysregulation induced by DSS, inhibited the growth of Sutterella, Prevotella_9 and Escherichia-Shigella harmful bacteria, and increased the abundance of Lachnospiraceae_NK4A136_group. At the same time, SCP treatment significantly inhibited the LPS-induced polarization of M1 macrophages, which may be mediated by two monopeptides, IPGAPGVP and TGPIGPPGSP, via FPR2. In conclusion, SCP can protect against colitis by modulating the intestinal microbiota composition and the intestinal barrier and inhibiting the polarization of M1 macrophages.

Ferulic acid ameliorates the quality of in vitro-aged bovine oocytes by suppressing oxidative stress and apoptosis.

Ferulic acid (FA) is a well-known natural antioxidant that scavenges oxygen free radicals and alleviates oxidative stress. This study investigated the chemopreventive potential of FA against bovine oocyte quality decline during in vitro aging. The results showed that 5 µM FA supplementation decreased the abnormality rate of in vitro-aged bovine oocytes. In addition, FA supplementation effectively improved antioxidant capacity by removing excessive ROS and maintaining intracellular GSH levels and antioxidant enzyme activity. The mitochondrial activity, mitochondrial membrane potential and intracellular ATP levels in aged bovine oocytes were obviously enhanced by FA supplementation. Furthermore, FA supplementation reduced in vitro aging-induced DNA damage and maintained DNA stability in bovine oocytes. Moreover, sperm binding assay showed the number of sperm that bound to the zona pellucida on aged bovine oocytes was significantly higher in the FA supplemented group than in the Aged group. Therefore, FA is beneficial for maintaining in vitro-aged bovine oocyte quality and could become a potential antioxidant for preventing bovine oocyte in vitro aging during in vitro maturation.

A missense mutation in Lama3 causes androgen alopecia.

Hair loss disorders such as androgenetic alopecia have caused serious disturbances to normal human life. Animal models play an important role in exploring pathogenesis of disease and evaluating new therapies. NIH hairless mice are a spontaneous hairless mouse discovered and bred in our laboratory. In this study, we resequenced the genomes of NIH normal mice and NIH hairless mice and obtained 3,575,560 high-quality, plausible SNP loci and 995,475 InDels. The Euclidean distance algorithm was used to assess the association of SNP loci with the hairless phenotype, at a threshold of 0.62. Two regions of chromosome 18 having the highest association with the phenotype contained 345 genes with a total length of 13.98 Mb. The same algorithm was used to assess the association of InDels with the hairless phenotype at a threshold of 0.54 and revealed a region of 25.45 Mb in length, containing 518 genes. The mutation candidate gene Lama3 (NM_010680.2: c.652C>T; NP_034810.1: p. Arg217Cys) was selected based on the results of functional gene analysis and mutation prediction screening. Lama3 (R217C) mutant mice were further constructed using CRISPR/Cas9 technology, and the relationship between Lama3 point mutations and the hairless phenotype were clarified by phenotypic observation. The results showed that male Lama3 point mutation mice started to lose hair on the 80th day after birth, and the hair loss area gradually expanded over time. H&E staining of skin sections showed that the point mutation mice had increased sebaceous glands in the dermis and missing hair follicle structure (i.e., typical symptoms of androgenetic alopecia). This study is a good extension of the current body of knowledge about the function of Lama3, and the constructed Lama3 (R217C) mutant mice may be a good animal model for studying androgenetic alopecia.

miR-146a-5p Alleviates Radiation-Induced Liver Fibrosis by Regulating PTPRA-SRC Signaling in Mice.

Patients with hepatobiliary tumors who accept radiotherapy are at risk for radiation-induced liver fibrosis. MicroRNAs (miRNAs) have been implicated in the pathogenesis of radiation-induced liver damage and possess potential as novel biomarkers and therapeutic targets. However, the role of miR-146a-5p in radiation-induced liver fibrosis is less well understood. The current study was designed to evaluate the role of miR-146a-5p in radiation-induced liver fibrosis in mice and to investigate the possible mechanisms involved in miR-146a-5p-mediated effects. The experiments were performed on Institute of Cancer Research (ICR) mice which received fractionated radiation (30 Gy in 5 fractions) to the liver. The results show radiation could induce histopathological changes, liver dysfunction and fibrosis accompanied with decreased miR-146a-5p expression. miR-146a-5p agomir treatment resulted in recovery of liver function and reduced the amount of alpha-smooth muscle actin (α-SMA), collagen 1, protein tyrosine phosphatase receptor type A (PTPRA) and phosphorylated SRC in the livers of irradiated mice. Therefore, our study reveals that miR-146a-5p inhibits the progression of hepatic fibrosis after radiation treatment. And the beneficial role of miR-146a-5p may be relevant to PTPRA-SRC signaling pathway.

Development of Nested Polymerase Chain Reaction with Novel Specific Primers for Detection of Tritrichomonas muris Infection in Laboratory Mice.

A variety of rodent ceca are parasitized by Tritrichomonas muris (T. muris), a flagellated protozoan. To date, there are no ideal methods for the detection of T. muris infections in laboratory mice; thus, new molecular methodologies for its specific detection need to be developed. In this study, using staining and SEM, it was observed that T. muris has a pear-shaped body and contains three anterior flagella. A nested PCR system with novel specific primers was designed based on the conserved regions of the SSU rRNA gene of T. muris. The nested PCR system for T. muris showed good specificity and high sensitivity for at least 100 T. muris trophozoites/mL and 0.1 ng/µL of fecal genomic DNA, which means that 176 trophozoites per gram of mouse feces could be detected. When using this nested PCR system, the detection rate was 18.96% (58/306), which was higher than the detection rate of 14.05% (43/306) detected via smear microscopy in fecal samples from five mouse strains. The sensitivity and specificity of nested PCR in detecting T. muris was found to be 100%, and it demonstrated a 26% increase in diagnostic sensitivity compared to the smear microscopy method in the present study. In conclusion, the nested PCR developed with novel primers based on the SSU rRNA gene of T. muris has good accuracy, specificity, and sensitivity for the detection of T. muris infections in laboratory mice.

Ferulic Acid Enhances Oocyte Maturation and the Subsequent Development of Bovine Oocytes.

Improving the quality of oocytes matured in vitro is integral to enhancing the efficacy of in vitro embryo production. Oxidative stress is one of the primary causes of quality decline in oocytes matured in vitro. In this study, ferulic acid (FA), a natural antioxidant found in plant cell walls, was investigated to evaluate its impact on bovine oocyte maturation and subsequent embryonic development. Bovine cumulus-oocyte complexes (COCs) were treated with different concentrations of FA (0, 2.5, 5, 10, 20 µM) during in vitro maturation (IVM). Compared to the control group, supplementation with 5 µM FA significantly enhanced the maturation rates of bovine oocytes and the expansion of the cumulus cells area, as well as the subsequent cleavage and blastocyst formation rates after in vitro fertilization (IVF) and somatic cell nuclear transfer (SCNT). Furthermore, FA supplementation was observed to effectively decrease the levels of ROS in bovine oocytes and improve their mitochondrial function. Our experiments demonstrate that FA can maintain the levels of antioxidants (GSH, SOD, CAT) in oocytes, thereby alleviating the oxidative stress induced by H2O2. RT-qPCR results revealed that, after FA treatment, the relative mRNA expression levels of genes related to oocyte maturation (GDF-9 and BMP-15), cumulus cell expansion (HAS2, PTX3, CX37, and CX43), and embryo pluripotency (OCT4, SOX2, and CDX2) were significantly increased. In conclusion, these findings demonstrate that FA supplementation during bovine oocyte IVM can enhance oocyte quality and the developmental potential of subsequent embryos.

Mammary Epithelial Cell-Derived Exosomal miR-221-3p Regulates Macrophage Polarization by Targeting Igf2bp2 during Mastitis.

Mastitis affects the milk quality and yield and is the most expensive disease in dairy cows. Elucidation of the pathogenesis of mastitis is of great importance for disease control. As a medium of intercellular communication, exosomes play key roles in various inflammatory diseases by regulating macrophage polarization. However, the molecular factors in exosomes that mediate the intercellular communication between mammary epithelial cells and macrophages during mastitis remain to be further explored. In this study, we isolated and identified mammary epithelial cell-derived exosomes from a lipopolysaccharide (LPS)/lipoteichoic acid (LTA)-induced mastitis cell model, and we demonstrated that exosomes from LPS/LTA-stimulated mammary epithelial cells promote M1-type macrophage polarization in vivo and in vitro. Based on the results of high-throughput sequencing, we constructed a differential miRNA (microRNA) expression profile of exosomes and demonstrated that miR-221-3p was highly expressed. Furthermore, in vivo and in vitro experiments, combined with coculture experiments and fluorescence tracing, showed that high miR-221-3p expression promoted M1-type macrophage polarization, demonstrating the transcellular role of miR-221-3p. Mechanistically, dual luciferase reporter gene assays and rescue assays showed that miR-221-3p regulated macrophage polarization by targeting Igf2bp2. The results of this study will deepen our understanding of the pathogenesis of mastitis, and the molecular regulatory axis that was established in this study is expected to be a target for mastitis treatment.