ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on X

Kidney Week

Abstract: TH-PO784

Defects in CLVS1 Gene Increase Glycolytic Activity in Cultured Human Podocytes

Session Information

Category: Glomerular Diseases

  • 1403 Podocyte Biology

Authors

  • Lane, Brandon M., Duke University School of Medicine, Durham, North Carolina, United States
  • Moore, Adolya M., Duke University, Durham, North Carolina, United States
  • Zhang, Sue, Duke University, Durham, North Carolina, United States
  • Peters, Hariel G., Duke University, Durham, North Carolina, United States
  • Wu, Guanghong, Duke University School of Medicine, Durham, North Carolina, United States
  • Chryst-Stangl, Megan, Duke University School of Medicine, Durham, North Carolina, United States
  • Gbadegesin, Rasheed A., Duke University School of Medicine, Durham, North Carolina, United States
Background

Increased oxidative stress is a common feature of chronic kidney disease. We have shown that the homozygous H310Y variant in the gene encoding clavesin-1 (CLVS1) is a cause of steroid sensitive nephrotic syndrome and disrupts podocyte endocytosis as well as binding of clavesin-1 to an antioxidant transporter. Human podocyte cells lines with CLVS1 knockout (KO) and homozygous H310Y knockin (KI) displayed increased levels of reactive oxygen species (ROS) and apoptosis that could be rescued by treatment with corticosteroids as well as ROS inhibitors. However, the precise effects of CLVS1 deficiencies on the metabolic profile of podocytes is unknown.

Methods

To identify differences in podocyte metabolic function due to deficiencies in CLVS1, we used an Agilent Seahorse XF Analyzer to examine CLVS1 KO, homozygous CLVS1 H310Y KI, corticosteroid treated CLVS1 H310Y KI, and control podocytes. Assays designed to measure ATP production, mitochondrial respiration, and glycolysis were used to examine differences between cell groups (N=15 for each).

Results

CLVS1 KO and H310Y KI podocytes displayed a more energetic cell phenotype compared to controls that included a higher level of overall ATP production and increased glycolytic activity (p<0.0001 for each). An almost two-fold increase in glycolysis, glycolytic capacity and glycolytic reserves were observed in KO and KI podocytes compared to controls (p<0.0001 for each). These levels were unaffected by steroid treatment. Differences in mitochondrial respiration were relatively minimal between control and CLVS1 KO or KI podocytes. However, increases in non-glycolytic acidification and non-mitochondrial oxygen consumption were observed in KO and KI podocytes (p<0.0001 for each), suggesting that additional physiological abnormalities may be present as well.

Conclusion

Defects in CLVS1 increase glycolysis-mediated ATP production in podocytes. Glycolysis is a key component of podocyte metabolic activity, particularly in foot process regulation and elevated ROS levels can induce a shift towards increased glycolytic activity. However, further studies are required to determine if this altered metabolic activity contributes to podocyte dysfunction due to deficiencies in CLVS1 or if it is a survival response to other cellular abnormalities including increased ROS levels.

Funding

  • Other NIH Support