Inhibition of myeloid differentiation factor 88(MyD88) by ST2825 provides neuroprotection after experimental traumatic brain injury in mice

Brain Res. 2016 Jul 15:1643:130-9. doi: 10.1016/j.brainres.2016.05.003. Epub 2016 May 4.

Abstract

Myeloid differentiation factor 88(MyD88) is an endogenous adaptor protein that plays an important role in coordinating intracellular inflammatory responses induced by agonists of the Toll-like receptor and interleukin-1 receptor families. MyD88 has been reported to be essential for neuronal death in animal models and may represent a therapeutic target for pharmacologic inhibition following traumatic brain injury (TBI). The purpose of the current study was to investigate the neuroprotective effect of MyD88 specific inhibitor ST2825 in an experimental mouse model of TBI. Intracerebroventricular (ICV) injection of high concentration (20μg/μL) ST2825 (15min post TBI) attenuated the development of TBI in mice, markedly improved neurological function and reduced brain edema. Decreased neural apoptosis and increased neuronal survival were also observed. Biochemically, the high concentration of ST2825 significantly reduced the levels of MyD88, further decreased TAK1, p-TAK1, nuclear p65 and increased IκB-α. Additionally, ST2825 significantly reduced the levels of Iba-1 and inflammatory factors TNF-α and IL-1β. These data provide an experimental rationale for evaluation of MyD88 as a drug target and highlight the potential therapeutic implications of ST2825 in TBI.

Keywords: Apoptosis; Myeloid differentiation factor 88; ST2825; Traumatic brain injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Brain / drug effects
  • Brain / metabolism
  • Brain / pathology
  • Brain Edema / etiology
  • Brain Edema / prevention & control
  • Brain Injuries, Traumatic / complications
  • Brain Injuries, Traumatic / metabolism*
  • Brain Injuries, Traumatic / pathology
  • Brain Injuries, Traumatic / prevention & control*
  • Cytokines / metabolism
  • Disease Models, Animal
  • Encephalitis / etiology
  • Encephalitis / metabolism
  • Encephalitis / prevention & control
  • Heterocyclic Compounds, 2-Ring / administration & dosage*
  • MAP Kinase Kinase Kinases / metabolism
  • Male
  • Mice
  • Mice, Inbred ICR
  • Myeloid Differentiation Factor 88 / antagonists & inhibitors*
  • Myeloid Differentiation Factor 88 / metabolism
  • Neurons / drug effects
  • Neurons / metabolism
  • Neurons / pathology
  • Neuroprotective Agents / administration & dosage*
  • Spiro Compounds / administration & dosage*
  • Zonula Occludens-1 Protein / metabolism

Substances

  • Cytokines
  • Heterocyclic Compounds, 2-Ring
  • Myd88 protein, mouse
  • Myeloid Differentiation Factor 88
  • Neuroprotective Agents
  • ST2825
  • Spiro Compounds
  • Tjp1 protein, mouse
  • Zonula Occludens-1 Protein
  • MAP Kinase Kinase Kinases
  • MAP kinase kinase kinase 7