Intrathecal lentivirus-mediated RNA interference targeting nerve growth factor attenuates myocardial ischaemia-reperfusion injury in rat

Br J Anaesth. 2019 Oct;123(4):439-449. doi: 10.1016/j.bja.2019.06.024. Epub 2019 Aug 2.

Abstract

Background: Nerve growth factor (NGF) has been implicated in hyperalgesia by sensitising nociceptors. A role for NGF in modulating myocardial injury through ischaemic nociceptive signalling is plausible. We examined whether inhibition of spinal NGF attenuates myocardial ischaemia-reperfusion injury and explored the underlying mechanisms.

Methods: In adult rats, lentivirus-mediated short-hairpin RNA targeted at reducing NGF gene expression (NGF-shRNA) or a transient receptor potential vanilloid 1 (TRPV1) antagonist (capsazepine) was injected intrathecally before myocardial ischaemia-reperfusion. Infarct size (expressed as the ratio of area at risk) and risk of arrhythmias were quantified. Whole-cell clamp patch electrophysiology was used to record capsaicin currents in primary dorsal root ganglion neurones. The co-expression of substance P (SP) and calcitonin gene-related peptide (CGRP), plus activation of TRPV1, protein kinase B (Akt) and extracellular signal-regulated kinase (ERK) were also quantified.

Results: NGF levels increased by 2.95 (0.34)-fold in dorsal root ganglion and 2.12 (0.27)-fold in spinal cord after myocardial ischaemia-reperfusion injury. Intrathecal injection of NGF-shRNA reduced infarct area at risk from 0.58 (0.02) to 0.37 (0.02) (P<0.01) and reduced arrhythmia score from 3.67 (0.33) to 1.67 (0.33) (P<0.01). Intrathecal capsazepine was similarly cardioprotective. NGF-shRNA suppressed expression of SP/CGRP and activation of Akt/ERK and TRPV1 in spinal cord. NGF increased capsaicin current amplitude from 144 (42) to 840 (132) pA (P<0.05), which was blocked by the TRPV1 antagonist 5'-iodoresiniferatoxin. Exogenous NGF enhanced capsaicin-induced Akt/ERK and TRPV1 activation in PC12 neuroendocrine tumour cells in culture.

Conclusions: Spinal NGF contributes to myocardial ischaemia-reperfusion injury by mediating nociceptive signal transmission.

Keywords: lentivirus; myocardial ischaemia–reperfusion; nerve growth factor; nociceptive signal; transient receptor potential vanilloid 1.

MeSH terms

  • Animals
  • Arrhythmias, Cardiac / prevention & control
  • Capsaicin / analogs & derivatives
  • Capsaicin / pharmacology
  • Cardiotonic Agents / administration & dosage
  • Cardiotonic Agents / therapeutic use
  • Ganglia, Spinal / drug effects
  • Ganglia, Spinal / metabolism
  • Genetic Therapy / methods*
  • Injections, Spinal
  • Lentivirus / genetics*
  • MAP Kinase Signaling System / drug effects
  • Myocardial Infarction / diagnostic imaging
  • Myocardial Infarction / prevention & control
  • Myocardial Reperfusion Injury / genetics*
  • Myocardial Reperfusion Injury / prevention & control*
  • Nerve Growth Factor / biosynthesis
  • Nerve Growth Factor / genetics*
  • PC12 Cells
  • Patch-Clamp Techniques
  • RNA, Small Interfering / administration & dosage*
  • RNA, Small Interfering / therapeutic use*
  • Rats
  • Rats, Sprague-Dawley
  • TRPV Cation Channels / antagonists & inhibitors
  • TRPV Cation Channels / metabolism

Substances

  • Cardiotonic Agents
  • RNA, Small Interfering
  • TRPV Cation Channels
  • Trpv1 protein, rat
  • Nerve Growth Factor
  • capsazepine
  • Capsaicin