Phosphatidylcholine Synthesis Declines with Age to Contribute to Mitochondrial Dysfunction

Key Takeaways

• Phosphatidylcholine synthesis drops with age in worms and humans
• SAMS‑1, PMT‑1/2 downregulation drives mitochondrial fragmentation and reduced respiration
• Dietary choline or PC restores mitochondrial function in aged models
• Human GTEx and UK Biobank show PEMT and PC decline, especially post‑menopause

Pulse Analysis

Mitochondrial decline is widely recognized as a central hallmark of aging, yet the endogenous processes that trigger this deterioration remain elusive. Recent work uncovers a conserved reduction in phosphatidylcholine (PC) synthesis, driven by age‑related downregulation of key methylation enzymes such as SAMS‑1 in nematodes and PEMT in humans. By integrating longitudinal proteomics, RNAi screens, and metabolomics, the study demonstrates that impaired PC production precipitates mitochondrial fragmentation, lowered oxidative phosphorylation, and heightened reactive oxygen species—features that mirror natural aging across species.

The experimental narrative spans from C. elegans to cultured mammalian cells and human population datasets. In worms, knockdown of sams‑1, pmt‑1, or pmt‑2 reproduces age‑associated mitochondrial defects, while supplementation with choline or directly with PC reverses fragmentation and restores respiration. Parallel analyses of GTEx gene expression and UK Biobank metabolomics reveal that PEMT expression and circulating PC concentrations decline with chronological age, with a pronounced effect in post‑menopausal women, a group already vulnerable to mitochondrial insufficiency. Lipidomics confirms that the restorative impact of choline is largely mediated through its conversion to PC, underscoring the pathway’s therapeutic relevance.

These insights position PC synthesis as a tractable target for interventions aimed at bolstering mitochondrial health in later life. Dietary choline, already recognized for its role in liver function and neural development, could be repurposed as a low‑cost, widely accessible strategy to mitigate age‑related metabolic decline. However, dosage, long‑term safety, and tissue‑specific effects require rigorous clinical evaluation. If validated, this approach may complement existing anti‑aging modalities such as caloric restriction mimetics, offering a synergistic avenue to preserve metabolic plasticity and improve healthspan for the aging population.