Abstract

Background

Undernutrition disrupts pregnant ewe’s metabolic homeostasis and severely inhibits fetal growth and development. In this study, undernourished and nutrition-recovery pregnant sheep models and rumen epithelial cells were utilized to investigate the mechanisms behind undernutrition-induced disruptions in male fetal rumen metabolism and development.

Results

Maternal undernutrition significantly reduced male fetal rumen weight and papilla length, width and surface area. Maternal undernutrition extremely suppressed nutrient metabolism and energy production in male fetal rumen via JAK3/STAT3 signaling to inhibit cell cycle progression and male fetal rumen development, while maternal nutritional recovery partially restored metabolic inhibition but failed to alleviate male fetal rumen development. Meanwhile, 64 differentially expressed miRNAs (DEMs) were identified in male fetal rumen between undernourished ewes and controls. Novel miR-736 was overexpressed both in male fetal rumen of undernourished and nutrition-recovery models. E2F transcription factor 2 (E2F2) and MYB proto-oncogene like 2 (MYBL2) were the intersection of male fetal rumen differentially expressed genes (DEGs) and DEMs target genes integrated analysis and were predicted as novel miR-736 target genes. Further, we confirmed that novel miR-736 targeted and downregulatedE2F2andMYBL2expression levels. SilencingE2F2andMYBL2promoted apoptosis and inhibited S-phase entry in rumen epithelial cells.

Conclusions

In summary, maternal undernutrition disrupted male fetal rumen metabolism and elevated novel miR-736, which targeted and downregulatedE2F2andMYBL2to inhibit cell cycle progression and promote apoptosis, finally inhibited male fetal rumen development. This study provides new insights into the epigenetic mechanisms underlying maternal undernutrition-induced male fetal rumen developmental deficits.

Data Availability

The raw sequencing data supporting this study have been deposited in the Gene Expression Omnibus (GEO) under controlled access, with rumen transcriptome data available through accession number GSE284288 (security token: qdqbggywvpehjif; direct link: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE284288&token=qdqbggywvpehjif ) and rumen miRNA sequencing data accessible via accession number GSE285445 (security token: wlqxqkmwbtoxtml; direct link: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE285445&token=wlqxqkmwbtoxtml ).

Abbreviations

  • BHBA:: β-Hydroxybutyrate
  • DEGs:: Differentially expressed genes
  • DEMs:: Differentially expressed miRNAs
  • E2F2:: E2F transcription factor 2
  • FC:: Fold change
  • MYBL2:: MYB proto-oncogene like 2
  • NC:: Negative control
  • NEFAs:: Non-esterified fatty acids
  • PCA:: Principal component analysis
  • PI:: Propidium iodide
  • PLS-DA:: Partial least squares discriminant analysis
  • PS:: Phosphatidylserine
  • TC:: Total cholesterol
  • TG:: Triglyceride

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Acknowledgements

We thank Biomarker Biotechnology Co., Ltd. (Beijing, China) for technical assistance on transcriptome sequencing and miRNA sequencing. Rumen epithelial cells were generously provided by Zhu Wen's team at Anhui Agricultural University.

Funding

This work was supported by the National Natural Science Foundation of China (32402767), National Key Research and Development Program of China (2022YFD1301102), Anhui Province Natural Science Foundation Youth Project (2308085QC104), and AAU Introduction of High-level Talent Funds (RC392107), Key Laboratory of Utilization of Livestock and Forage Resources in Circum-Tarim Region (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs (BSGJSYS202502), the China Agriculture Research System (CARS-38).

Ethics Declaration

Ethics approval and consent to participate

The animal experiments were approved by the Institutional Animal Care and Use Committee of Anhui Agricultural University (AHAUXMSQ2024073).

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

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