Adipolin protects against renal injury via PPARα-dependent reduction of inflammasome activation

Lixin Fang1, Koji Ohashi2, Satoko Hayakawa1

  • 1Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.

Iscience
|May 30, 2023
PubMed

Insights

Adipolin protects against chronic kidney disease (CKD) by reducing kidney inflammation. This adipokine enhances ketone body production, mitigating renal injury and fibrosis through the PPARα/HMGCS2 pathway.

Area of Science:

  • Nephrology
  • Metabolic research
  • Molecular biology

Background:

  • Chronic kidney disease (CKD) is a significant global health issue with incompletely understood mechanisms.
  • Adipolin, an adipokine, has previously demonstrated benefits in cardiometabolic diseases.
  • The specific role of adipolin in the pathogenesis of CKD requires further investigation.

Purpose of the Study:

  • To elucidate the role of adipolin in the development and progression of chronic kidney disease.
  • To investigate the molecular pathways through which adipolin exerts its effects on renal tissue.
  • To determine if adipolin can serve as a therapeutic target for mitigating kidney injury.

Main Methods:

  • Utilized a mouse model of subtotal nephrectomy to induce remnant kidney injury.
  • Assessed the impact of adipolin deficiency and administration on markers of kidney damage, fibrosis, and oxidative stress.
  • Examined the regulation of ketone body production and inflammasome activation in renal tissue.
  • Investigated the involvement of the PPARα/HMGCS2 pathway in adipolin's protective effects.

Main Results:

  • Adipolin deficiency exacerbated kidney injury, including albuminuria, tubulointerstitial fibrosis, and oxidative stress, via inflammasome activation.
  • Adipolin treatment increased ketone body (β-hydroxybutyrate) production and HMGCS2 expression in the remnant kidney.
  • Adipolin attenuated inflammasome activation in proximal tubular cells through a PPARα/HMGCS2-dependent mechanism.
  • Systemic adipolin administration protected against renal injury in wild-type mice, an effect blunted in PPARα-deficient mice.

Conclusions:

  • Adipolin confers protection against renal injury in the context of CKD.
  • This protective effect is mediated by the reduction of renal inflammasome activation.
  • Adipolin induces HMGCS2-dependent ketone body production via PPARα activation, thereby mitigating kidney damage.

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