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Abstract Background Gonadotropin precisely controls mammalian reproductive activities. Systematic analysis of the mechanisms by which epigenetic modifications regulate the synthesis and secretion of gonadotropin can be useful for more precise regulation of the animal reproductive process. Previous studies have identified many differential m6A modifications in the GnRH-treated adenohypophysis. However, the molecular mechanism by which m6A modification regulates gonadotropin synthesis and secretion remains unclear. Results Herein, it was found that GnRH can promote gonadotropin synthesis and secretion by promoting the expression of FTO. Highly expressed FTO binds to Foxp2 mRNA in the nucleus, exerting a demethylation function and reducing m6A modification. After Foxp2 mRNA exits the nucleus, the lack of m6A modification prevents YTHDF3 from binding to it, resulting in increased stability and upregulation of Foxp2 mRNA expression, which activates the cAMP/PKA signaling pathway to promote gonadotropin synthesis and secretion. Conclusions Overall, the study reveals the molecular mechanism of GnRH regulating the gonadotropin synthesis and secretion through FTO-mediated m6A modification. The results of this study allow systematic interpretation of the regulatory mechanism of gonadotropin synthesis and secretion in the pituitary at the epigenetic level and provide a theoretical basis for the application of reproductive hormones in the regulation of animal artificial reproduction.

The incidence of ulcerative colitis (UC) is increasing each year, and its course is characterized by alternating remission-relapse; currently, there is no effective treatment for UC. Peptides produced from the hydrolysis of walnut proteins have physiological functions such as anti-inflammatory and antioxidant properties. The aim of this study was to analyze the preventive effect of walnut polypeptide (WP) on UC and to preliminarily screen bioactive peptides in WP. The results of in vitro experiments showed that WP was able to alleviate the LPS-induced inflammatory response by inhibiting M1 polarization in Raw 264.7 cells and thereby alleviating the LPS-induced inflammatory response. The results of in vivo experiments showed that dietary supplementation with 500 mg/kg WP significantly alleviated dextran sodium sulfate (DSS)-induced weight loss, colon shortening, and elevated DAI scores. WP treatment was able to suppress DSS-induced inflammatory responses in mice by inhibiting macrophage M1 polarization and NF-κB signaling pathway. WP intervention also helped maintain intestinal barrier integrity by promoting tight junction protein expression and mucus secretion. In addition, 16S rDNA sequencing showed that WP ameliorated gut microbial disorder induced by DSS, as evidenced by a decrease in the abundance of harmful bacteria (Erysipelatoclostridium, Helicobacter, and Parasutterella) and an increase in the abundance of beneficial bacteria (Flavonifractor, Anaerotignum, and Alistipes) after WP intervention. In conclusion, this study demonstrates that WP ameliorates DSS-induced colonic inflammation in mice by inhibiting inflammation, modulating the gut microbiota and repairing the intestinal barrier.

Summary: Milk fat is an important indicator for evaluating the quality of cow’s milk. In this study, we used bovine mammary epithelial cells (BMECs) to investigate the role and molecular mechanism of KLF4 in the regulation of milk fat synthesis. The results showed that KLF4 was more highly expressed in mammary tissues of high-fat cows compared with low-fat cows. KLF4 positively regulated the expression of genes related to milk fat synthesis in BMECs, increasing intracellular triglycerides content, and KLF4 promoted milk fat synthesis by activating the PI3K-AKT-mTOR signaling pathway. Furthermore, the results of animal experiments also confirmed that knockdown of KLF4 inhibited milk fat synthesis. In addition, yeast one-hybrid assays and dual-luciferase reporter gene assays confirmed that KLF4 directly targets and binds to the fatty acid synthase (FASN) promoter region to promote FASN transcription. These results demonstrate that KLF4 is a key transcription factor for milk fat synthesis in BMECs.

Abstract 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.

Ulcerative colitis (UC) is incurable, and rational dietary interventions are important in preventing UC. Kombucha is a fermented beverage that originated in China and has a variety of activities, including antioxidant, antibacterial and hypoglycemic activities. The aim of this study was to analyze the protective effect of Kombucha polysaccharide (KP) against UC and determine its mechanism of action. The results showed that KP intervention was effective in alleviating dextran sulfate sodium salt (DSS)-induced colitis symptoms and inhibiting DSS-induced inflammation and oxidative stress. Moreover, KP was able to reduce intestinal permeability, promote the expression of tight junction proteins, and help maintain thrush cell numbers and promote mucus secretion. The 16S rDNA results indicated that KP intervention increased the abundance of Rikenellaceae_RC9_gut_group and Clostridiales_unclassified. Untargeted metabolomics techniques revealed that KP can reverse DSS-induced disorders in intestinal metabolism. This study demonstrated that KP alleviated DSS-induced colitis by helping maintain intestinal barrier integrity, regulating the gut microbiota and remodeling metabolism pathways. The findings provide a theoretical basis for the application of KP as a dietary supplement for the prevention of UC.

The incidence of kidney renal clear cell carcinoma (KIRC) is rising worldwide, and the prognosis is poor. Cuproptosis is a new form of cell death that is dependent on and regulated by copper ions. The relationship between cuproptosis and KIRC remains unclear. In the current study, changes in cuproptosis-related genes (CRGs) in TCGA-KIRC transcriptional datasets were characterized, and the expression patterns of these genes were analyzed. We identified three main molecular subtypes and discovered that multilayer CRG changes were associated with patient clinicopathological traits, prognosis, elesclomol sensitivity, and tumor microenvironment (TME) cell infiltration characteristics. Then, a CRG score was created to predict overall survival (OS). The CRG score was found to be strongly linked to the TME. These findings may help elucidate the roles of CRGs in KIRC, potentially enhancing understanding of cuproptosis and supporting the development of more effective immunotherapy strategies.

Mastitis, which affects milk quality and yield, is one of the most common diseases in dairy cows, causing large economic losses. Cow mastitis is classified into clinical and subclinical types. Subclinical mastitis presents without obvious lesions in the udder or noticeable change in milk samples, indicating persistent chronic infection that is difficult to detect and treat. Therefore, finding specific biomarkers is of great significance for the early diagnosis and treatment of subclinical mastitis. As mediators of intercellular communication, exosomes have been shown to be extensively involved in various physiological and pathological processes in the body. Exosomes in milk, blood, and cell supernatant can carry stable cell source-specific nucleic acids, proteins, and metabolites. Hence, exosomes show great application prospects for early diagnosis, targeted therapy, and disease mechanism analysis. In this review, we summarize the biogenesis, biological functions, and methods of isolating and identifying exosomes and review the current status of exosome research related to mastitis. Finally, in view of the application of exosomes to diagnose, treat, and perform disease mechanism analysis in mastitis, deficiencies in recent research on mastitis exosomes are described, and the direction of future exosome research efforts in mastitis is proposed.

Abstract Background With the widespread use of rifampicin and isoniazid, bacterial resistance has become a growing problem. Additionally, the lack of relevant baseline information for the frequency of drug-resistant tuberculosis (TB) gene mutations is a critical issue, and the incidence of this infection in the city of Changchun has not investigated to date. However, compared with the slow traditional methods of drug susceptibility testing, recently developed detection methods, such as rifampicin and isoniazid resistance-related gene chip techniques, allow for rapid, easy detection and simultaneous testing for mutation frequency and drug resistance. Methods In this study, the rifampicin and isoniazid resistance-related gene mutation chip method was employed for an epidemiological investigation. To assess the gene mutation characteristics of drug-resistant TB and evaluate the chip method, we tested 2143 clinical specimens from patients from the infectious diseases hospital of Changchun city from January to December 2016. The drug sensitivity test method was used as the reference standard. Results The following mutation frequencies of sites in the rifampicin resistance gene rpoB were found: Ser531Leu (52.6%), His526Tyr (12.3%), and Leu511Pro (8.8%). The multidrug-resistance (MDR)-TB mutation frequency was 34.7% for rpoB Ser531Leu and katG Ser315Thr, 26.4% for rpoB Ser531Leu and inhA promoter − 15 (C → T), and 10.7% for rpoB His526Tyr and katG Ser315Thr. In addition, drug susceptibility testing served as a reference standard. In previously treated clinical cases, the sensitivity and specificity of GeneChip were 83.1 and 98.7% for rifampicin resistance, 79.9 and 99.6% for isoniazid resistance, and 74.1 and 99.8% for MDR-TB. Conclusions Our experimental results show that the chip method is accurate and reliable; it can be used to detect the type of drug-resistant gene mutation in clinical specimens. Moreover, this study can be used as a reference for future research on TB resistance baselines.

Mice with spontaneous coat mutations are ideal animal models for studying skin development and tumorigenesis. In this study, skin hair growth cycle abnormalities were examined in NIH hairless mice 42 days after birth (P42) by using hematoxylin-eosin (H&E) staining. To examine the gene expression patterns in the skin of mutant mice, the dorsal skin of P42 female NIH mice and NIH hairless mice was sequenced by RNA-Seq, and 5,068 differentially expressed genes (DEGs) were identified (false discovery rate [FDR] ≥ 2, P < 0.05). A pathway analysis showed that basal cell carcinoma, the cell cycle and the Hippo, Hedgehog and Wnt signaling pathways were up-regulated in NIH hairless mice. Previous studies have shown that these pathways are closely associated with cell proliferation, cell cycle, organ size and cancer development. In contrast, signal transduction, bacterial and parasitic infection, and receptor-mediated pathways, including calcium signaling, were down-regulated in NIH hairless mice. A gene interaction network analysis was performed to identify genes related to hair follicle development. To verify the reliability of the RNA-Seq results, we used q-PCR to analyze 12 key genes identified from the gene interaction network analysis, including eight down-regulated and four up-regulated genes, and the results confirmed the reliability of the RNA-Seq results. Finally, we constructed the differential gene expression profiles of mutant mice by RNA-Seq. NIH hairless mice exhibited abnormalities in hair development and immune-related pathways. Pik3r1 and Pik3r3 were identified as key genes, laying the foundation for additional in-depth studies of hairless mice.

ObjectiveNasopharyngeal carcinoma (NPC) is a common malignant tumour in Southeast Asia, especially in southern China. ABO blood groups have been proven to play an important role in many cancers. However, it is still controversial whether the ABO blood group has a definite relationship to susceptibility to NPC and the prognosis of NPC patients. This meta-analysis was performed to elucidate the correlation between ABO blood group and NPC to provide more data for clinical practice.MethodsA systematic search was performed of the Chinese National Knowledge Infrastructure (CNKI), Wanfang, Web of Science, EMBASE, and PubMed databases up to December 31, 2020. Stata 11.0 statistical software was used for this meta-analysis.ResultsAccording to the inclusion and exclusion criteria, a total of 6 studies including 6938 patients with NPC were selected. Blood group O was relevant to Chinese NPC patients, and patients with blood group O had a significantly lower incidence of NPC, while blood group A had no correlation with susceptibility to NPC. There was no difference in the 3-year overall survival (OS), locoregional relapse-free survival (LRRFS) or distant metastasis-free survival (DMFS) rates between patients with blood group O and those with non-O blood groups; worse 5-year OS, LRRFS and DMFS rates were found in patients with blood group O, whereas blood group A was not related to prognosis.ConclusionBlood group O in Chinese patients with NPC seems to be a protective factor for morbidity. However, once patients with blood group O are diagnosed with NPC, this blood group often indicates unfavourable OS, LRRFS and DMFS rates. It is recommended that more attention should be paid to the influence of blood group factor on patients in the treatment of NPC.