Autophagy Enhancement Without Lysosomal Biogenesis Is Like Hiring More Garbage Trucks With No Dump — It Makes Things Worse

The longevity field is obsessed with autophagy induction. Rapamycin. Spermidine. TFEB overexpression. But inducing autophagy is only half the equation. You're creating more autophagosomes that need to fuse with lysosomes for degradation. If lysosomal capacity doesn't scale, you just jam the system with unresolved autophagic intermediates.

This is exactly what happens in aged cells. Lysosomal pH rises (less acidic), cathepsin activity drops, and lipofuscin accumulates (the undegradable garbage that clogs lysosomes). Turning up autophagy in this context floods already-overwhelmed lysosomes with cargo they can't process.

Hypothesis: Autophagy induction in aged organisms without concurrent lysosomal biogenesis and acidification will produce net negative outcomes after initial benefit. The window of autophagy benefit closes as lysosomal capacity saturates, typically within 2-4 weeks of sustained induction.

Prediction: Rapamycin treatment in 24-month-old mice will show initial benefit (weeks 1-3) followed by deterioration (weeks 4-8) in cellular markers, unless co-administered with a lysosomal acidification agent (e.g., acidic nanoparticles as per Bhatt et al., 2023).