Dexmedetomidine ameliorates acute kidney injury by regulating mitochondrial dynamics via the α2-AR/SIRT1/PGC-1α pathway activation in rats

Mol Med. 2024 Oct 25;30(1):184. doi: 10.1186/s10020-024-00964-y.

Abstract

Background: Sepsis-associated acute kidney injury (AKI) is a serious complication of systemic infection with high morbidity and mortality in patients. However, no effective drugs are available for AKI treatment. Dexmedetomidine (DEX) is an alpha 2 adrenal receptor agonist with antioxidant and anti-apoptotic effects. This study aimed to investigate the therapeutic effects of DEX on sepsis-associated AKI and to elucidate the role of mitochondrial dynamics during this process.

Methods: A lipopolysaccharide (LPS)-induced AKI rat model and an NRK-52E cell model were used in the study. This study investigated the effects of DEX on sepsis-associated AKI and the molecular mechanisms using histologic assessment, biochemical analyses, ultrastructural observation, western blotting, immunofluorescence, immunohistochemistry, qRT-PCR, flow cytometry, and si-mRNA transfection.

Results: In rats, the results showed that administration of DEX protected kidney structure and function from LPS-induced septic AKI. In addition, we found that DEX upregulated the α2-AR/SIRT1/PGC-1α pathway, protected mitochondrial structure and function, and decreased oxidative stress and apoptosis compared to the LPS group. In NRK-52E cells, DEX regulated the mitochondrial dynamic balance by preventing intracellular Ca2+ overloading and activating CaMKII.

Conclusions: DEX ameliorated septic AKI by reducing oxidative stress and apoptosis in addition to modulating mitochondrial dynamics via upregulation of the α2-AR/SIRT1/PGC-1α pathway. This is a confirmatory study about DEX pre-treatment to ameliorate septic AKI. Our research reveals a novel mechanistic molecular pathway by which DEX provides nephroprotection.

Keywords: Acute kidney injury; Apoptosis; Dexmedetomidine; Mitochondrial dynamics; α2-AR/SIRT1/PGC-1α.

MeSH terms

  • Acute Kidney Injury* / drug therapy
  • Acute Kidney Injury* / etiology
  • Acute Kidney Injury* / metabolism
  • Adrenergic alpha-2 Receptor Agonists / pharmacology
  • Adrenergic alpha-2 Receptor Agonists / therapeutic use
  • Animals
  • Apoptosis / drug effects
  • Cell Line
  • Dexmedetomidine* / pharmacology
  • Dexmedetomidine* / therapeutic use
  • Disease Models, Animal
  • Lipopolysaccharides / adverse effects
  • Male
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • Mitochondrial Dynamics* / drug effects
  • Oxidative Stress / drug effects
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha* / genetics
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha* / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Adrenergic, alpha-2 / genetics
  • Receptors, Adrenergic, alpha-2 / metabolism
  • Sepsis / complications
  • Sepsis / drug therapy
  • Sepsis / metabolism
  • Signal Transduction* / drug effects
  • Sirtuin 1* / genetics
  • Sirtuin 1* / metabolism

Substances

  • Dexmedetomidine
  • Sirtuin 1
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Receptors, Adrenergic, alpha-2
  • Sirt1 protein, rat
  • Ppargc1a protein, rat
  • Lipopolysaccharides
  • Adrenergic alpha-2 Receptor Agonists