Abstract: TH-PO383

Protein Bound Uremic Toxins p-Cresyl Sulfate and Indoxyl Sulfate Modulate the Human Endothelial Cells’ Transcriptome

Session Information

Category: Cell Biology

  • 201 Cell Signaling, Oxidative Stress

Authors

  • Cunha, Regiane Stafim da, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
  • Favretto, Giane, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
  • Gregório, Paulo Cézar, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
  • Maciel, Rayana Ariane Pereira, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
  • Busato, Valentina, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
  • Pecoits-Filho, Roberto, Pontifícia Universidade Católica do Paraná, Curitiba, Paraná, Brazil
  • Barreto, Fellype C., Universidade Federal do Paraná, Curitiba, Paraná, Brazil
  • Souza, Wesley M., Universidade Federal do Paraná, Curitiba, Paraná, Brazil
  • Stinghen, Andréa Marques, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
Background

p-Cresyl sulfate (PCS) and indoxyl sulfate (IS) are protein bound uremic toxins associated with endothelial dysfunction in chronic kidney disease (CKD). Thus, PCS and IS could activate signaling pathways leading to changes in the cellular transcriptome. This study evaluated the effect of PCS and IS on the expression of Organic Anion Transporter (OAT) 1 and 3 and their transcription factors cAMP responsive element binding protein-1 (CREB1), activating transcription factor-1 (ATF1) and hepatocyte nuclear factor-4α (HNF4α).

Methods

Human endothelial cells were treated for 24 h at normal, uremic and maximal uremic concentration of PCS (0.08, 1.75 and 2.6 mg/L) and IS (0.6, 53 and 236 mg/L). Probenecid (Pb) and benzilpenicilin (Bp) were used as OATs inhibitors, vitamin C (Vit C) as antioxidant and the N-nitro-Larginine methyl ester (L-NAME) as the inhibitor of nitric oxide (NO) synthase in order to evaluate the NO pathway production. Cell viability was assessed by MTT. The protein levels of OAT1 and OAT3 was evaluated by Western blotting. CREB1, ATF-1 and HNF4α expression were evaluated by RT-qPCR.

Results

The cell viability was reduced (P<0.001) after PCS and IS treatments in dose-dependent manner, being restored with Pb or Bp (P<0.001). An increased OAT1 and OAT3 protein expression was observed after PCS treatment at maximal uremic concentration (P<0.05). The RT-qPCR analysis showed an increase (P<0.01) in the CREB1 and ATF1 expression in cells treated with PCS and IS, which was restored with Pb, Bp, Vit C and L-NAME (P<0.05). The HNF4α expression was increased (P<0.05) only after PCS treatments at maximal uremic concentration.

Conclusion

PCS and IS are able to modulate differentially the gene expression of transcription factors which could affect the OATs expression. These changes in the cellular transcriptome could lead to the pathological phenotype found in CKD.