TNF-α impairs platelet function by inhibiting autophagy and disrupting metabolism via syntaxin 17 downregulation

J Clin Invest. 2025 Jun 10;135(15):e186065. doi: 10.1172/JCI186065. eCollection 2025 Aug 1.

Abstract

Platelets play a dual role in hemostasis and inflammation-associated thrombosis and hemorrhage. Although the mechanisms linking inflammation to platelet dysfunction remain poorly understood, our previous work demonstrated that TNF-α alters mitochondrial mass, platelet activation, and autophagy-related pathways in megakaryocytes. Here, we hypothesized that TNF-α impairs platelet function by disrupting autophagy, a process critical for mitochondrial health and cellular metabolism. Using human and murine models of TNF-α-driven diseases, including myeloproliferative neoplasms and rheumatoid arthritis, we found that TNF-α downregulates syntaxin 17 (STX17), a key mediator of autophagosome-lysosome fusion. This disruption inhibited autophagy, leading to the accumulation of dysfunctional mitochondria and reduced mitochondrial respiration. These metabolic alterations compromised platelet-driven clot contraction, a process linked to thrombotic and hemorrhagic complications. Our findings reveal a mechanism by which TNF-α disrupts hemostasis through autophagy inhibition, highlighting TNF-α as a critical regulator of platelet metabolism and function. This study provides potentially new insights into inflammation-associated pathologies and suggests autophagy-targeting strategies as potential therapeutic avenues to restore hemostatic balance.

Keywords: Autophagy; Hematology; Metabolism; Mitochondria; Platelets.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autophagy*
  • Blood Platelets* / metabolism
  • Blood Platelets* / pathology
  • Down-Regulation*
  • Humans
  • Mice
  • Mice, Knockout
  • Mitochondria / genetics
  • Mitochondria / metabolism
  • Mitochondria / pathology
  • Qa-SNARE Proteins* / genetics
  • Qa-SNARE Proteins* / metabolism
  • Tumor Necrosis Factor-alpha* / genetics
  • Tumor Necrosis Factor-alpha* / metabolism

Substances

  • Tumor Necrosis Factor-alpha
  • Qa-SNARE Proteins
  • STX17 protein, human