Current models often treat the aging cell as a closed system, or at least one where external variables stay fixed. But we should consider whether the Anthropocene is fundamentally shifting the thermodynamic grounds of the proteome.

We know Liquid-Liquid Phase Separation (LLPS) acts as a master regulator of cellular organization, governing everything from nucleolar assembly to the formation of stress granules. These phase transitions are remarkably sensitive to intracellular pH and ionic strength; a shift of only 0.1 pH units can be the tipping point between a functional liquid droplet and the terminal, solid aggregates found in ALS or Alzheimer’s.

Here’s the speculative part: are we failing to account for how rising atmospheric $CO_2$ affects the kinetic stability of the human proteome?

The blood’s bicarbonate buffer is robust, but maintaining that tight pH gradient comes with a metabolic cost that increases as ambient $CO_2$ levels climb. We’re effectively living in a state of chronic, low-grade respiratory acidosis. While the body compensates in the short term, over several decades this subtle shift may be lowering the Gibbs free energy barrier for protein misfolding.

What if the 'epidemic' of neurodegeneration isn't merely an artifact of longer lifespans, but a forced thermodynamic transition? If our intracellular environment is becoming slightly more acidic or ionically imbalanced because of external atmospheric shifts, we’re essentially 'salting' the solutions of our own cells. This makes it much easier for disordered proteins like $FUS$ or $TDP-43$ to crash out of solution.

This is a massive, uncontrolled experiment at the metabolic-atmospheric interface. If this hypothesis holds, our current longevity interventions are ignoring a primary external driver. We need high-resolution studies on environmental proteostasis—specifically comparing protein aggregation kinetics in controlled atmospheric chambers that mimic pre-industrial versus modern $CO_2$ levels.

It’s possible that to solve aging, we don't just need better drugs, but a different atmosphere. This is a blind spot in biogerontology that requires immediate collaboration between climate scientists and biophysicists. If the 'biological clock' is partially geared to the planet's chemistry, we’re in deeper trouble than we thought.