Humanin analogue, HNG, inhibits platelet activation and thrombus formation by stabilizing platelet microtubules

J Cell Mol Med. 2020 Apr;24(8):4773-4783. doi: 10.1111/jcmm.15151. Epub 2020 Mar 16.

Abstract

HNG, a highly potent mutant of the anti-Alzheimer peptide-humanin, has been shown to protect against ischaemia-reperfusion (I/R) injury. However, the underlying mechanism related to platelet activation remains unknown. We proposed that HNG has an effect on platelet function and thrombus formation. In this study, platelet aggregation, granule secretion, clot retraction, integrin activation and adhesion under flow conditions were evaluated. In mice receiving HNG or saline, cremaster arterial thrombus formation induced by laser injury, tail bleeding time and blood loss were recorded. Platelet microtubule depolymerization was evaluated using immunofluorescence staining. Results showed that HNG inhibited platelet aggregation, P-selectin expression, ATP release, and αIIb β3 activation and adhesion under flow conditions. Mice receiving HNG had attenuated cremaster arterial thrombus formation, although the bleeding time was not prolonged. Moreover, HNG significantly inhibited microtubule depolymerization, enhanced tubulin acetylation in platelets stimulated by fibrinogen or microtubule depolymerization reagent, nocodazole, and inhibited AKT and ERK phosphorylation downstream of HDAC6 by collagen stimulation. Therefore, our results identified a novel role of HNG in platelet function and thrombus formation potentially through stabilizing platelet microtubules via tubulin acetylation. These findings suggest a potential benefit of HNG in the management of cardiovascular diseases.

Keywords: humanin; microtubule; platelet activation; platelet aggregation; thrombus formation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / genetics
  • Animals
  • Blood Coagulation / drug effects
  • Blood Coagulation / genetics
  • Blood Platelets / drug effects
  • Blood Platelets / metabolism
  • Histone Deacetylase 6 / genetics*
  • Humans
  • Intracellular Signaling Peptides and Proteins / genetics*
  • Intracellular Signaling Peptides and Proteins / pharmacology
  • Mice
  • Microtubules / genetics
  • Microtubules / metabolism
  • P-Selectin / genetics
  • Platelet Activation / drug effects
  • Platelet Activation / genetics
  • Platelet Aggregation / drug effects
  • Signal Transduction / drug effects
  • Thrombosis / drug therapy*
  • Thrombosis / genetics
  • Thrombosis / pathology

Substances

  • HNG peptide
  • Intracellular Signaling Peptides and Proteins
  • P-Selectin
  • humanin
  • Adenosine Triphosphate
  • Hdac6 protein, mouse
  • Histone Deacetylase 6