Heart saver: Comprehensive investigation of (redox-) proteomic and thiol metabolite changes induced by Cana-, Dapa-, Empagliflozin treatment in 2D and 3D heart cell models reveals increased mitochondrial activity and glutathione redox defense and involvement of redox signaling

Abstract

Aims Antidiabetic drugs, sodium-glucose co-transporter-2 inhibitors (SGLT-2i), have demonstrated heart-saving properties independently of the diabetes status of a patient. We aimed to discover SGLT-2i-specific cardiac targets. Materials and methods Two cardiac cell lines (AC16 and HCM) were treated with low-end therapeutic and 100- or 1000-fold dose of cana-, dapa and empagliflozin to investigate their influence on the (redox) proteome and thiol metabolome. Furthermore, we mimicked reperfusion injury (RI) on stem-cell derived cardioids to examine if and how SGLT-2i help to cope with RI. Key findings We show that gliflozins increase glutathione synthesis and trigger autophagy already at low drug concentration, visible through increase in ATG13. On the (redox) proteome level, several potential targets could be identified: 10 proteins affected by low concentration across all three drugs (including TXN and NAPRT) in HCM cells and 16 downregulated proteins shared between all high drug treatments in HCM cells and cardioids. Among the latter were GSR, PRDX2, LAMTOR5 and the catalytic subunit of PP2A. On the redox proteome level, we found among others, PKM, PPP1CA, PRDX5 and MDH2 with redox affected cysteine sites in both HCM and AC16 cells, and additionally, PKM, MDH2 and PPP2CA in both HCM and cardioids. Significance Our data suggest that gliflozin treatments affect the cells' capacity to buffer redox stress by increasing glutathione and altering redox state of key cysteine residues of proteins involved in the cellular defense against oxidative stress.