Uterine microbiome shifts from stochastic to deterministic assembly in aged laying hens, with Rhodococcus ruber spermidine production rescuing oxidative phosphorylation impairment (microbiomejournal.biomedcentral.com)

• Uterine aging in laying hens shifts microbiota assembly from stochastic to deterministic, enriching Rhodococcus.
• Multi-omics (single-cell transcriptomics, metabolomics) identified spermidine as a key microbial metabolite.
• Spermidine rescues oxidative phosphorylation by inducing mitophagy via PINK1/Parkin pathway.
• PARP1-mediated NAD+ depletion drives energy impairment; Rhodococcus ruber colonization restores ATP production.
• Study funded by Chinese national grants; collaboration between Chinese and Canadian institutions.

"A study in Microbiome reports that reproductive aging in laying hens drives a shift from stochastic to deterministic microbial community assembly in the uterus, selecting for Rhodococcus. Multi-omics analyses showed that this deterministic shift compensates for age-related energy decline. The aged uterus suffered oxidative phosphorylation impairment due to PARP1-mediated NAD+ depletion from DNA damage. Colonization by Rhodococcus ruber or administration of its metabolite spermidine rescued this phenotype by inducing PINK1/Parkin-mediated mitophagy, restoring ATP production for eggshell biomineralization. The research was funded by Chinese national grants and involved institutions from China and Canada."