Aug 2026· Wetchasan sattawaphaet = The Thai journal of veterinary medicine· Vol 56, pp. 1-14· 0 citations
TL;DR
This study provides the first comprehensive temporal transcriptomic atlas of the donkey endometrium, revealing conserved endocrine–immune–metabolic regulatory networks comparable to those in mares and cattle.
Abstract
The endometrium undergoes extensive cyclical remodeling essential for reproductive success; however, the molecular mechanisms governing these processes in donkeys (Equus asinus) remain poorly characterized. To address this gap, we performed high-throughput RNA sequencing on endometrial tissues collected from Dezhou donkeys (n = 16) at four post-ovulation stages: Day 0 (ovulation), Day 3 (early luteal), Day 7 (mid-luteal), and Day 18 (late luteal/pre-luteolysis). Differential gene expression analysis, Gene Ontology enrichment, and KEGG pathway mapping were conducted to characterize temporal transcriptomic dynamics. We identified 2,474, 6,548, and 1,288 differentially expressed genes in Day 0 versus Day 3, Day 0 versus Day 7, and Day 0 versus Day 18 comparisons, respectively. A biphasic transcriptional pattern emerged: transient suppression of immune and cytokine signaling pathways at Day 3 was followed by robust activation of TNF, NF-κB, PI3K-Akt, and extracellular matrix–receptor interaction pathways by Day 7, consistent with progesterone-driven stromal proliferation and tissue remodeling. By Day 18, enrichment of cytochrome P450, steroid hormone biosynthesis, and amino acid metabolism pathways indicated metabolic reprogramming associated with luteal regression. This study provides the first comprehensive temporal transcriptomic atlas of the donkey endometrium, revealing conserved endocrine–immune–metabolic regulatory networks comparable to those in mares and cattle. These findings establish a molecular foundation for developing precision strategies to improve uterine health, fertility management, and assisted reproductive technologies in donkeys.
In cattle, the second week after estrus encompasses critical changes in uterine function. The endometrium will either prepare for the release of luteolytic pulses of prostaglandin-F2 alpha or for the support of an eventual pregnancy. We hypothesized that concentrations of amino acids and lipids in the uterine luminal fluid (ULF), and the gene expression in luminal epithelial cells (LE), change across the second week of the estrous cycle. The objective was to compare amino acid and lipid concentrations in ULF and target gene expression in LE 7 (D7), 10 and 14 d after estrus. The ULF and LE samples were collected from the uterine body of five primiparous, non-lactating, cyclic Bos indicus-influenced crossbred cows using a cytological brush on each day after synchronized estrus. Targeted metabolomics of ULF was performed using mass spectrometry, and gene expression in LE was assessed using RNA sequencing. Data were analyzed by uni- and multivariate statistics. Multivariate analyses separated D7, D10, and D14, with amino acid metabolism and lipid biosynthesis as enriched pathways. Luminal concentrations of amino acids (e.g., arginine, histidine) and lipids (e.g., CE(17:1), PC aa C34:1) increased from D7 to D10, but from D10 to D14 concentrations of amino acids (e.g., glutamine, glutamic acid) decreased while that of lipids (e.g., CE(18:2), SM C16:0) continued to increase. Transcriptomic profiling revealed temporal regulation of 186 amino acid-related and 133 lipid-related genes. Between D7 and D10, there was increased expression of genes for oxidative phosphorylation and extracellular secretion pathways supporting secretory capacity, while decreased expression of genes in arginine-proline metabolism and solute carrier-mediated transport pathways promoted luminal metabolite accumulation. From D10 to D14, there was increased expression of genes in fatty acid elongation and sphingolipid metabolism pathways likely driving lipid synthesis and amino acid catabolism, while decreased expression of genes in protein digestion/absorption and PI3K/AKT signaling pathways reduced nutrient export to the lumen. ULF composition and LE gene expression changed markedly during the second week of the estrous cycle. It is plausible that the dynamic shifts in amino acid and lipid metabolites in the uterine lumen reflect changing responses to sex steroids. The influence of such changes on embryo development and pregnancy success in cattle warrants investigation.
Abdul Waheed, C. C. Rocha, Alexandra Bennett Bastien et al.· Journal of Animal Science an...· 0 citations
The present study aimed to identify and characterize bovine endometrial miRNAs at different stages of the estrous cycle. Total RNA was extracted from endometrial tissue and subjected to small RNA sequencing. A total of 334 miRNAs were expressed in bovine endometrial tissue during the estrous cycle. Among them, 11 were differentially expressed miRNAs (DEMs) at the follicular stage (F-DEMs) and four at the luteal stage (L-DEMs) in comparison between F and L stages. Bioinformatic analysis of the target genes of these DEMs revealed that miR-2411-3p and miR-320a were the top-ranked hub miRNAs in F- and L-DEMs, respectively. These two miRNAs demonstrated the highest functional coverage in GO annotation. The analysis using cultured bovine endometrial cells showed that the expression level of miR-2411-3p was significantly high in the E2-treated group compared to the control (p < 0.05), whereas the expression level of miR-320a was significantly high in the P4-treated group (p < 0.05). The present study identified the endometrial DEMs during the estrous cycle and predicted their functions based on their target genes. The results demonstrated that miR-2411-3p and miR-320a were identified as characteristic endometrial miRNAs regulated by ovarian steroid hormones in bovine.
Rafikul Islam, Manamu Takenouchi, Amir Salama et al.· Animal science journal = Nih...· 0 citations
We explored the potential functions of differentially expressed miRNAs, mRNAs, lncRNAs, and circRNAs identified in the ovaries of gilts with normal estrus (NE) and follicular cyst-associated anestrus (AE), as well as their putative competing endogenous RNA (ceRNA) regulatory networks. Ovarian morphology was assessed via ultrasonography, and serum concentrations of Follicle-stimulating hormone (FSH), (Estradiol) E2, and Progesterone(P4) were measured. Ovarian tissues were harvested after slaughter for whole-transcriptome sequencing. Bioinformatic tools were used to screen differentially expressed RNAs(DERNAs) between NE and AE gilts. We further predicted target interactions among these transcripts, conducted functional enrichment analysis on target genes, and constructed candidate ceRNA regulatory networks potentially associated with gilt estrus. Phenotypic verification confirmed that ovarian ultrasonographic characteristics, histological morphology, and serum reproductive hormone levels were consistent with the physiological status of NE and AE gilts. Under the screening thresholds of p < 0.05 and |log2FC| ≥ 1, we identified 22 lncRNAs that may interact with 21 mRNAs via 50 miRNAs, alongside 39 circRNAs predicted to regulate 26 mRNAs through 72 miRNAs. Functional enrichment analysis indicated that target genes of these differentially expressed transcripts were predominantly enriched in the lysosome pathway, PPAR signaling pathway, chemokine signaling pathway, cholesterol metabolism and NOD-like receptor signaling pathway. Hub molecules including FGF1, GHR, TLR2, ssc-miR-370, and miR-21-5p were shared in lncRNA/circRNA-miRNA-mRNA regulatory networks; these molecules have been reported to participate in progesterone synthesis, estrus modulation, and endocrine homeostasis. Of particular interest, two non-coding RNAs, MSTRG.1285.1 and novel_circ_056113, were predicted to act as candidate ceRNAs that may sponge ssc-miR-370 and miR-21-5p, which could in turn modulate the expression of estrus-associated mRNAs including FGF1, GHR, and TLR2. The expression trends of MSTRG.1285.1, novel_circ_056113, miR-370, miR-21-5p, GHR, TLR2, and FGF1 were validated by qRT-PCR, and the quantification results agreed with transcriptome sequencing data. Collectively, this study constructed a predicted ceRNA regulatory network of ovarian transcripts comparing NE and AE gilts and uncovered multiple RNA molecules potentially involved in estrus regulation. These findings offer preliminary theoretical clues for exploring the onset of puberty in gilts.
Ling-Yan Lv, Jiaqing Zhang, Xianhua Wu et al.· International Journal of Mol...· 0 citations
Effective reproductive management in cattle, such as cows and buffaloes, requires early and accurate pregnancy detection. Early identification of pregnancy enables farmers to promptly identify non-pregnant animals for treatment and/or rebreeding, thereby reducing the calving interval. This study aimed to standardize the expression of the CCL8 and CXCL10 genes as markers for early pregnancy detection in Murrah buffaloes. Blood samples were collected on the 16th day post-artificial insemination for gene expression analysis and on days zero, seven, 14, and 21 post-artificial insemination for progesterone concentration measurement. Buffaloes were categorized as pregnant (n = 6) or non-pregnant (n = 6) based on the resumption of estrus. Gene expression levels in peripheral blood leukocytes were analyzed using Quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) with SYBR green dye. Amplicons of CCL8, CXCL10, and GAPDH genes were measured 108, 117, and 158 bp, respectively. Results showed that CCL8 mRNA expression in pregnant buffaloes was 5.13 and 12.21 times higher compared to non-pregnant buffaloes, while CXCL10 mRNA expression was 4.19 and 22.17 times higher. These findings indicated significantly elevated CCL8 and CXCL10 mRNA expression levels in peripheral blood leukocytes of pregnant buffaloes on the 16th day. Progesterone levels in the pregnant group were increased significantly from day zero to day 21, while no significant differences were observed between groups on days zero, seven and 14. Pregnancy was further confirmed via per-rectal examination on the 45th day post-artificial insemination Therefore, CCL8 and CXCL10 gene expression profiling on the 16th day could serve as reliable early pregnancy markers in Murrah buffaloes.
Aman Srivastav, V. Singh, Riyaj Ahmed Siddique et al.· Veterinary Research Forum· 0 citations
Folliculogenesis is a complex process essential to female fertility, characterized by multifaceted communication between oocytes and granulosa cells (GCs). While transcriptional regulation during folliculogenesis has been extensively studied, the proteomic landscape remains largely unexplored. Here, we profiled both the proteomic and transcriptomic landscapes of single oocytes and their surrounding mini-bulk GCs across four consecutive stages, from secondary to preovulatory follicles. Integrated dual-omics analysis provided a high-resolution characterization of cell type-specific transcriptional and proteomic changes. Proteomic profiling revealed coordinated metabolic programs, in which oocytes shift toward lipid storage while GCs enhance energy production and steroidogenic metabolism to support oocyte maturation. These metabolic changes in oocytes were accompanied by dynamic remodeling of mitochondrial organization. In addition, we identified novel transcription factors involved in regulating folliculogenesis, as well as a SATB1-centered regulatory network that may reflect preparatory chromatin remodeling preceding zygotic genome activation. Furthermore, GDF9-BMPR2 signaling progressively increased from the secondary stage to the preovulatory stage, indicating strengthened intercellular communication between oocytes and GCs. Together, these findings provide mechanistic insights into oocyte development and follicle growth, with potential implications for novel fertility treatments and diagnostic strategies.
Hongchao Li, Xinshuai Zhang, Huimin Kang et al.· Genomics, Proteomics & Bioin...· 0 citations
This study attempted to investigate the pathogenic mechanism of endometritis and discover potential biomarkers for diagnosing and treating endometritis, finding hub genes (ALDH3A2 and ACSS3) play critical roles in the pathogenesis of endometritis by interacting with different metabolites.