Gypenoside XLIX protects against acute kidney injury by suppressing IGFBP7/IGF1R-mediated programmed cell death and inflammation

Phytomedicine. 2021 May:85:153541. doi: 10.1016/j.phymed.2021.153541. Epub 2021 Mar 5.

Abstract

Background: Acute kidney injury (AKI), characterised by excessive inflammatory cell recruitment and programmed cell death, has a high morbidity and mortality; however, effective and specific therapies for AKI are still lacking.

Objective: This study aimed to evaluate the renoprotective effects of gypenoside XLIX (Gyp XLIX) in AKI.

Methods: The protective effects of Gyp XLIX were tested in two AKI mouse models established using male C57BL/6 mice (aged 6-8 weeks) by a single intraperitoneal injection of cisplatin (20 mg/kg) or renal ischemia-reperfusion for 40 min. Gyp XLIX was administered intraperitoneally before cisplatin administration or renal ischemia-reperfusion. Renal function, tubular injury, renal inflammation and programmed cell death were evaluated. In addition, the renoprotective effects of Gyp XLIX were also evaluated in cisplatin- or hypoxia-treated tubular epithelial cells. The mechanisms underlying these effects were then explored using RNA sequencing.

Results: In vivo, Gyp XLIX substantially suppressed the increase in serum creatinine and blood urea nitrogen levels. Moreover, tubular damage was alleviated by Gyp XLIX as shown by periodic acid-Schiff staining, electron microscopy and molecular analysis of KIM-1. Consistently, we found that Gyp XLIX suppressed renal necroptosis though the RIPK1/RIPK3/MLKL pathway. The anti-inflammatory and antinecroptotic effects were further confirmed in vitro. Mechanistically, RNA sequencing showed that Gyp XLIX markedly suppressed the levels of IGF binding protein 7 (IGFBP7). Co-immunoprecipitation and western blot analysis further showed that Gyp XLIX reduced the binding of IGFBP7 to IGF1 receptor (IGF1R). Additionally, picropodophyllin, an inhibitor of IGF1R, abrogated the therapeutic effects of Gyp XLIX on cisplatin-induced renal cell injury; this finding indicated that Gyp XLIX may function by activating IGF1R-mediated downstream signalling Additionally, we also detected the metabolic distribution of Gyp XLIX after injection; Gyp XLIX had a high concentration in the kidney and exhibited a long retention time. These findings may shed light on the application of Gyp XLIX for AKI treatment clinically.

Conclusion: Gyp XLIX may serve as a potential therapeutic agent for AKI treatment via IGFBP7/ IGF1R-dependent mechanisms.

Keywords: Acute kidney injury; Cisplatin; Gypenoside XLIX; IGFBP7; Inflammation; Necroptosis; Renal ischemia/reperfusion injury.

MeSH terms

  • Acute Kidney Injury / chemically induced
  • Acute Kidney Injury / drug therapy*
  • Animals
  • Apoptosis / drug effects
  • Cell Line
  • Cisplatin
  • Humans
  • Inflammation / metabolism
  • Insulin-Like Growth Factor Binding Proteins / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Necroptosis
  • Protective Agents / pharmacology*
  • Receptor, IGF Type 1 / metabolism*
  • Saponins / pharmacology*

Substances

  • 3-((O-6-deoxymannopyranosyl-1-2-O-(xylopyranosyl-1-3)arabinopyranosyl)oxy)-21-glucopyranosyloxy-20-hydroxydammar-24-en-19-al
  • Igf1r protein, mouse
  • Insulin-Like Growth Factor Binding Proteins
  • Protective Agents
  • Saponins
  • insulin-like growth factor binding protein-related protein 1
  • Receptor, IGF Type 1
  • Cisplatin