Tetrahydrocurcumin provides neuroprotection in rats after traumatic brain injury: autophagy and the PI3K/AKT pathways as a potential mechanism

J Surg Res. 2016 Nov;206(1):67-76. doi: 10.1016/j.jss.2016.07.014. Epub 2016 Jul 15.

Abstract

Background: Tetrahydrocurcumin provides neuroprotection in multiple neurologic disorders by modulating oxidative stress, inflammatory responses, and autophagy. However, in traumatic brain injury (TBI), it is unclear whether a beneficial effect of tetrahydrocurcumin exists. In this study, we hypothesized that administration of tetrahydrocurcumin provides neuroprotection in a rat model of TBI.

Material and methods: Behavioral studies were performed by recording and analyzing beam-walking scores. The role of tetrahydrocurcumin on neurons death was assessed via Nissl staining. We then performed Western blot analyses, terminal deoxynucleotidyl transferase 2'-deoxyuridine-5'-triphosphate (dUTP) nick end labeling assays and immunofluorescence staining to evaluate autophagy and apoptosis. Phospho-protein kinase B (p-AKT) was also assessed via Western blotting.

Results: Our data indicated that administration of tetrahydrocurcumin alleviated brain edema, attenuated TBI-induced neuron cell death, decreased the degree of apoptosis and improved neurobehavioral function, which were accompanied by enhanced autophagy and phospho-AKT after TBI. Moreover, the autophagy inhibitor 3-methyladenine and the PI3K kinase inhibitor LY294002 partially reversed the neuroprotection of tetrahydrocurcumin after TBI.

Conclusions: This study indicates that tetrahydrocurcumin protects neurons from TBI-induced apoptotic neuronal death, which may be through modulation autophagy and PI3K/AKT pathways. Thus, tetrahydrocurcumin may be an attractive therapeutic agent for TBI.

Keywords: Apoptosis; Autophagy; PI3K/AKT signaling pathway; Tetrahydrocurcumin; Traumatic brain injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Autophagy / drug effects
  • Biomarkers / metabolism
  • Blotting, Western
  • Brain Injuries, Traumatic / drug therapy*
  • Brain Injuries, Traumatic / metabolism
  • Brain Injuries, Traumatic / physiopathology
  • Curcumin / analogs & derivatives*
  • Curcumin / pharmacology
  • Curcumin / therapeutic use
  • Fluorescent Antibody Technique
  • In Situ Nick-End Labeling
  • Male
  • Neuroprotective Agents / pharmacology
  • Neuroprotective Agents / therapeutic use*
  • Phosphatidylinositol 3-Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Random Allocation
  • Rats
  • Rats, Sprague-Dawley
  • Treatment Outcome

Substances

  • Biomarkers
  • Neuroprotective Agents
  • tetrahydrocurcumin
  • Phosphatidylinositol 3-Kinases
  • Proto-Oncogene Proteins c-akt
  • Curcumin