Effect of the sGC activator BAY 60-2770 on human proximal tubular (HK-2) cells under hypoxia and after TGF-β1 treatment

Increasing cGMP levels by modulating soluble guanylyl cyclase (sGC) can be renoprotective. While sGC stimulators can modulate cGMP levels, their application is limited as they require native sGC to function. sGC activators on the other hand can function with heme-free sGC. Therefore, we tested the renoprotective effects of the sGC activator BAY 60-2770 that also functions with oxidized sGC in an acute kidney injury (AKI) model with transition to chronic kidney disease (CKD). In order to study the effects of BAY 60-2770 on gene expression in tubular cells, we used the proximal tubular cell line HK-2 as a model. To mimic the ischemia and fibrosis observed in vivo, we subjected HK-2 cells to hypoxia and TGF-β1 treatment, respectively. RNASeq analysis showed that BAY 60-2770 had a significant influence on the expression of genes involved in fibrosis, inflammation and tissue damage after both hypoxia and TGF-β1 treatments. HK-2 cells were treated with BAY 60-2770 or solvent control and incubated for 24h either under hypoxia (0.3% oxygen) or normoxia. In another set of experiments, HK-2 cells were treated with TGF-β1 alone or in combination with BAY 60-2770 and incubated for 24h under normoxia. Analysis of RNA-seq data was performed using DESeq2 with a multifactor design within two experiments, comparing both treatment effects and sGC activator status to the respective controls.