Dexmedetomidine Inhibits TLR4/NF-κB Activation and Reduces Acute Kidney Injury after Orthotopic Autologous Liver Transplantation in Rats

Sci Rep. 2015 Nov 20:5:16849. doi: 10.1038/srep16849.

Abstract

Patients who undergo orthotopic liver transplantation often sustain acute kidney injury(AKI). The toll-like receptor 4(TLR4)/Nuclear factor-кB(NF-кB) pathway plays a role in AKI. Dexmedetomidine(Dex) has been shown to attenuate AKI. The current study aimed to determine whether liver transplantation-induced AKI is associated with inflammatory response, and to assess the effects of dexmedetomidine pretreatment on kidneys in rats following orthotopic autologous liver transplantation(OALT). Seventy-seven adult male rats were randomized into 11 groups. Kidney tissue histopathology and levels of blood urea nitrogen(BUN) and serum creatinine(SCr) were evaluated. Levels of TLR4, NF-κB, tumor necrosis factor-α, and interleukin-1β levels were measured in kidney tissues. OALT resulted in significant kidney functional impairment and tissue injury. Pre-treatment with dexmedetomidine decreased BUN and SCr levels and reduced kidney pathological injury, TLR4 expression, translocation of NF-κB, and cytokine production. The effects of dexmedetomidine were reversed by pre-treatment with atipamezole and BRL44408, but not ARC239. These results were confirmed by using α2A-adrenergic receptor siRNA which reversed the protective effect of dexmedetomidine on attenuating NRK-52E cells injury induced by hypoxia reoxygenation. In conclusion, Dexmedetomidine-pretreatment attenuates OALT-induced AKI in rats which may be contributable to its inhibition of TLR4/MyD88/NF-κB pathway activation. The renoprotective effects are related to α2A-adrenergic receptor subtypes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Kidney Injury / etiology
  • Acute Kidney Injury / metabolism
  • Acute Kidney Injury / prevention & control*
  • Adrenergic alpha-2 Receptor Agonists / pharmacology
  • Animals
  • Blood Urea Nitrogen
  • Cell Line
  • Creatinine / blood
  • Dexmedetomidine / pharmacology*
  • Enzyme-Linked Immunosorbent Assay
  • Interleukin-1beta / metabolism
  • Liver Transplantation / adverse effects
  • Liver Transplantation / methods*
  • Male
  • Microscopy, Confocal
  • Myeloid Differentiation Factor 88 / metabolism
  • NF-kappa B / metabolism*
  • RNA Interference
  • Random Allocation
  • Rats, Sprague-Dawley
  • Receptors, Adrenergic, alpha-2 / genetics
  • Receptors, Adrenergic, alpha-2 / metabolism
  • Signal Transduction / drug effects
  • Toll-Like Receptor 4 / metabolism*
  • Transplantation, Autologous
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Adrenergic alpha-2 Receptor Agonists
  • Interleukin-1beta
  • Myeloid Differentiation Factor 88
  • NF-kappa B
  • Receptors, Adrenergic, alpha-2
  • Toll-Like Receptor 4
  • Tumor Necrosis Factor-alpha
  • Dexmedetomidine
  • Creatinine