The Protein Kinase R Inhibitor C16 Alleviates Sepsis-Induced Acute Kidney Injury Through Modulation of the NF-κB and NLR Family Pyrin Domain-Containing 3 (NLPR3) Pyroptosis Signal Pathways

Med Sci Monit. 2020 Oct 5:26:e926254. doi: 10.12659/MSM.926254.

Abstract

BACKGROUND Protein kinase R (PKR) is implicated in the inflammatory response to bacterial infection while the role of PKR in sepsis-induced acute kidney injury (AKI) is largely unknown. This study aimed to investigate the effects of the specific PKR inhibitor C16 (C13H8N4OS) on lipopolysaccharide (LPS)-induced AKI, and its mechanisms of action. MATERIAL AND METHODS C57BL/6J mice were injected intraperitoneally with C16 or vehicle 1 h before the LPS challenge and then injected intraperitoneally with LPS or 0.9% saline. After the LPS challenge, histopathological damage, renal function, and levels of proinflammatory cytokines were assessed. All the related signaling pathways were analyzed. RESULTS C16 effectively inhibited LPS-induced renal elevation of proinflammatory cytokines and chemokines. C16 prevented NF-kappaB activation and suppressed the PKR/eIF2alpha signaling pathway in AKI after the LPS challenge. Furthermore, C16 significantly inhibited pyroptosis during AKI, as evidenced by decreased renal levels of apoptosis-associated speck-like protein; NACHT, LRR, NLR Family Pyrin Domain-Containing 3; caspase-1; interleukin (IL)-1ß; and IL-18. CONCLUSIONS Our findings suggest that inhibition by C16 ameliorated LPS-induced renal inflammation and injury, at least partly through modulation of the pyroptosis signal pathway in the kidney.

MeSH terms

  • Acute Kidney Injury* / drug therapy
  • Acute Kidney Injury* / etiology
  • Acute Kidney Injury* / metabolism
  • Acute Kidney Injury* / pathology
  • Animals
  • Indoles / pharmacology*
  • Mice
  • NF-kappa B / metabolism*
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism*
  • Pyroptosis / drug effects*
  • Sepsis* / complications
  • Sepsis* / drug therapy
  • Sepsis* / metabolism
  • Sepsis* / pathology
  • Signal Transduction / drug effects*
  • Thiazoles / pharmacology*
  • eIF-2 Kinase / antagonists & inhibitors*
  • eIF-2 Kinase / metabolism

Substances

  • GW 506033X
  • Indoles
  • NF-kappa B
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Nlrp3 protein, mouse
  • Thiazoles
  • eIF-2 Kinase
  • protein kinase R, mouse