Novel TRH analog improves motor and cognitive recovery after traumatic brain injury in rodents

Am J Physiol. 1999 Oct;277(4):R1196-204. doi: 10.1152/ajpregu.1999.277.4.R1196.

Abstract

Thyrotropin-releasing hormone (TRH) and certain TRH analogs show substantial neuroprotective effects in experimental brain or spinal cord trauma but also have other physiological actions (autonomic, analeptic, and endocrine) that may be undesirable for the treatment of neurotrauma in humans. We developed a novel TRH analog (2-ARA-53a), with substitutions at the NH(2)-terminus and imidazole ring, that preserves the neuroprotective action of TRH-like compounds while decreasing or eliminating their autonomic, analeptic, and endocrine effects. Rats administered 2-ARA-53a (1.0 mg/kg, n = 17) intravenously 30 min after lateral fluid percussion brain injury showed marked improvement in motor recovery compared with vehicle-treated controls (n = 14). Treatment of mice subjected to moderate controlled cortical impact brain injury, at the same dose and time after trauma (n = 8), improved both motor recovery and cognitive performance in a water maze place learning task compared with vehicle-treated controls (n = 8). In injured rats, no autonomic or analeptic effects were observed with this compound, and endocrine effects were significantly reduced with 2-ARA-53a, in contrast to those found with a typical NH(2)-terminal-substituted TRH analog (YM-14673). These findings demonstrate that the neuroprotective effects of TRH-related compounds can be dissociated from their other major physiological actions and suggest a potential role for dual-substituted TRH analogs in the treatment of clinical neurotrauma.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Autonomic Nervous System / drug effects
  • Autonomic Nervous System / physiopathology
  • Azetidines / pharmacology
  • Brain Injuries / mortality
  • Brain Injuries / physiopathology*
  • Brain Injuries / psychology*
  • Central Nervous System Stimulants / pharmacology
  • Cognition / drug effects*
  • Dipeptides / pharmacology
  • Endocrine Glands / drug effects
  • Endocrine Glands / physiopathology
  • Male
  • Maze Learning / drug effects
  • Mice
  • Mice, Inbred C57BL
  • Motor Activity / drug effects*
  • Nervous System / drug effects
  • Nervous System / physiopathology
  • Rats
  • Rats, Sprague-Dawley
  • Thyrotropin-Releasing Hormone / analogs & derivatives*

Substances

  • Azetidines
  • Central Nervous System Stimulants
  • Dipeptides
  • Thyrotropin-Releasing Hormone
  • azetirelin