What is the Origin of Protein Synthesis Response Blunting?

This concept is derived from muscle physiology, combining 'protein synthesis' (the anabolic process) with 'blunting' (a reduction in the expected magnitude of response).

What is the Mechanism of Protein Synthesis Response Blunting?

Blunting often involves impaired signaling through the mTOR pathway, which acts as the central sensor for anabolic stimuli. This impairment can stem from chronic activation of inhibitory kinases, often triggered by systemic inflammation or excessive glucocorticoid signaling. Additionally, reduced tissue sensitivity to insulin or reduced availability of key signaling intermediates can prevent the necessary phosphorylation events required for efficient ribosomal translation initiation.

Protein Synthesis Response Blunting ∞ Area

Protein Synthesis Response Blunting

Meaning

Protein Synthesis Response Blunting is a state where skeletal muscle or other anabolic tissues exhibit a diminished capacity to increase the rate of protein synthesis following normally potent stimuli, such as resistance exercise or high-quality amino acid ingestion. This phenomenon is a hallmark of anabolic resistance and contributes significantly to sarcopenia. Clinically, we observe a reduced post-prandial or post-exercise nitrogen retention.