Overexpression of the histidine triad nucleotide-binding protein 2 protects cardiac function in the adult mice after acute myocardial infarction

Acta Physiol (Oxf). 2020 Apr;228(4):e13439. doi: 10.1111/apha.13439. Epub 2020 Jan 21.


Aim: To explore the role of the histidine triad nucleotide-binding 2 (HINT2) protein in heart failure.

Methods: Neonatal mouse ventricle myocytes (NMVMs) and myocardial infarction-induced heart failure mice were used for in vitro or in vivo experiments. Adenovirus (ADV) and adeno-associated virus serum type 9 (AAV9) vectors were used to regulate HINT2 expression. The expression of HINT2 was determined by quantifying the mRNA and protein levels. Cell survival was analysed using the CCK-8 kit and TUNEL staining. Mitochondrial function was determined by the mitochondrial membrane potential and oxygen consumption rates. AAV9-HINT2 was injected 24 h post-myocardial infarction following which transthoracic echocardiography and histological analyses were performed after 4 weeks. Positron emission tomography tomography-computed tomography (PET/CT) and targeted metabolomics analyses were used to explore the metabolic status in vivo. NAD levels were measured using a colorimetric kit. Computer-simulated rigid body molecular docking was performed using AUTODOCK4. Molecule binding kinetics assays were performed using biolayer interferometry.

Results: HINT2 was down-regulated in NMVMs in hypoxia. ADV-HINT2-induced HINT2 overexpression improved NMVM survival after exposure to hypoxia. Mitochondrial function was preserved in the ADV-HINT2 group under hypoxic conditions. In vivo experiments showed that cardiac function and metabolic status was preserved by HINT2 overexpression. HINT2 overexpression restored mitochondrial NAD levels; this was dependent on nicotinamide mononucleotide (NMN). Using computer-simulated molecular docking analysis and biolayer interferometry, we observed that HINT2 potentially binds and associates with NMN.

Conclusion: HINT2 overexpression protects cardiac function in adult mice after myocardial infarction by maintaining mitochondrial NAD homeostasis.

Keywords: heart failure; mitochondrial function; myocardial infarction; nicotinamide adenine dinucleotide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Heart / physiology*
  • Hydrolases / metabolism*
  • Male
  • Membrane Potential, Mitochondrial
  • Mice
  • Mice, Inbred C57BL
  • Mitochondrial Proteins / metabolism*
  • Molecular Docking Simulation
  • Myocardial Infarction / metabolism*
  • Myocytes, Cardiac / metabolism
  • NAD / metabolism
  • Oxygen Consumption
  • Positron Emission Tomography Computed Tomography


  • Mitochondrial Proteins
  • NAD
  • Hydrolases
  • HINT2 protein, mouse