Oral Presentation ESA-SRB-NZSE-CaSR 2026 in conjunction with ENSA

Proteomic mapping of preconception environmental and endocrine stress signalling in the mouse caput epididymis (144071)

Jess E. Mulhall 1 2 , Natalie A. Trigg 1 2 , Amanda L. Anderson 1 2 , Anne-Louise Gannon 1 2 , David A. Skerrett-Byrne 3 4 5 6 , Brett Nixon 1 2
  1. Centre for Reproductive Science, School of Environmental and Life Sciences, University of Newcastle, Callaghan , NSW, Australia
  2. Reproductive and Family Health Research Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
  3. Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Bavaria, Germany
  4. German Center for Diabetes Research (DZD), Neuherberg, Bavaria, Germany
  5. Mercy Hospital for Women, Mercy Perinatal, Heidelberg, VIC, Australia
  6. Therapeutics Discovery and Vascular Function in Pregnancy Group, Department of Obstetrics, Gynaecology and Newborn Health, Melbourne Medical School, The University of Melbourne, , Heidelberg, VIC, Australia

Background

Paternal health before conception can influence offspring disease risk by shaping the sperm epigenome and the developmental trajectory of the next generation. We have identified the caput epididymis as a key site of soma-sperm communication during which the sperm epigenome (i.e., small non-coding RNA (sncRNA) profile) is extensively remodelled. However, the mechanisms through which distinct paternal stressors alter epididymal signalling remain poorly defined. Here, we investigated how environmental and endocrine stress impact the proteome of caput epididymal epithelial cells.

 

Methods

Adult male Swiss mice were exposed for 7-days to either corticosterone (CORT; 25 mg/kg body weight/day via drinking water) or thermal stress (Heat; 8h at 35°C, 16h at 25°C) alongside matched controls (n = 4 biological replicates/treatment). Caput epididymides were collected and subjected to proteomic analysis using label-free nLC-MS/MS.

 

Results

We achieved unprecedented proteome depth of the caput epididymal epithelial cells in both Heat (n = 6,466) and CORT (n = 6,168) exposure groups, with 6,088 proteins shared. Relative to matched controls, 17 and 23 proteins were significantly dysregulated following Heat and CORT exposures, respectively (-1.5≤FC≥1.5, p-value≤0.05). Ingenuity Pathway Analysis revealed shared pathways implicating RNA processing, vesicular trafficking and inositol signalling. CORT, however, preferentially affected Rho/Rab regulation, protein trafficking, mitochondrial-redox metabolism, and antigen-presenting-cell activation, suggesting coordinated changes in stress sensing and cargo handling. Whereas, Heat engaged PI3K-AKT-mTOR, COPI/COPII transport, cytoskeletal and microtubule organisation processes, which may regulate extracellular vesicle biogenesis and cargo loading.

 

Conclusion

These findings provide a detailed proteomic map illustrating how paternal stressors remodel the biochemistry of caput epididymal cells; revealing patterns of common and stressor-specific molecular responses and establishing a framework for identifying where environmental/endocrine stressors converge and differ in terms of shaping the sperm sncRNA cargo. Such data will help define soma-sperm signalling pathways that may be prioritised for therapeutic intervention.