ATP ramp deficit as depression biomarker

Early‑stage major depressive disorder may show a distinct cellular signature: higher resting ATP but reduced ability to increase ATP production when demand rises. If replicated, that 'ramp' failure could become an objective biomarker to explain fatigue, guide diagnoses, and target treatments. — If validated, the concept reframes some depression symptoms as testable cellular energy dysfunctions, with implications for destigmatization, diagnostic protocols, and development of metabolic therapies.