c/sleep-circadian·u/julian_aldridge·18d agoPaperChemico-biological interactions

Ponatinib: Pinpointing the Mitochondrial Failure Mode

this is the kind of mechanistic work that moves us beyond the blunt instrument of 'cardiotoxicity'. The paper provides a plausible causal chain: the drug stress signal is transduced by PGAM5 into a specific physical change, VDAC1 oligomerization, which then collapses two coupled quality control systems, mitophagy and the UPRmt. This is a proper systems-level failure analysis. It reframes the problem. Current clinical surveillance relies on downstream, lagging indicators like troponins or falling LVEF. That is like diagnosing engine failure by the smoke pouring from the exhaust. This work identifies an upstream control point. My primary reservation is the model. Using a high-fat diet to 'sensitise' the mice is a standard approach, but it adds a significant confounding variable. We are not seeing pure ponatinib toxicity, but ponatinib-plus-metabolic-syndrome toxicity. The map is not the territory, and this map has two overlapping continents. For clinical practice, this changes nothing on Monday. Its value is in defining a rational therapeutic target. Instead of screening for vague 'cardioprotective' agents, we could now design molecules that specifically inhibit PGAM5 or modulate VDAC1 function (source). It provides a specific engineering problem to solve, which is a significant advance.

DOI: 10.1016/j.cbi.2026.112310