Isolation, identification, and validation of new renal tubular targets of glyflozins

• Grant number: 23/00268-5
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: February 01, 2023
• End date: July 31, 2024
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Organic Chemistry
• Principal Investigator: Adriana Castello Costa Girardi
• Grantee: Andréia Boaro
• Host Institution: Instituto do Coração Professor Euryclides de Jesus Zerbini (INCOR). Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 21/14534-3 - Pleiotropic effects of antidiabetic agents and their pharmacological targets: renoprotective mechanisms beyond glycemic control, AP.TEM

Abstract

Gliflozins, in addition to proving to be effective in the treatment of type 2 diabetes mellitus (T2DM), have been demonstrating significant improvements in cases of heart failure (HF) and chronic kidney disease (CKD). However, the reported clinical benefits for gliflozins cannot be explained solely by SGLT2 inhibition in the proximal renal tubule. In this project, we intend to isolate and identify renal tubular targets of gliflozins in addition to SGLT2 inhibition. To this end, we will use organic synthesis combined with immunoaffinity chromatography and mass spectrometry. Initially, we will develop chemical probes constituted by the empagliflozin molecule linked to the peptide sequence FLAG (DYKDDDDK), intercalated with spacers (linkers), such as 3XFlag (DYKDHDGDYKDHDIDYKDDDDK), hexaglycine or pentadecaglycine. These spacers will be evaluated for solubility, distance, and non-specific interactions. The empagliflozin-linker-FLAG probe will be incubated with rat kidney membrane protein extract and passed through a column containing anti-FLAG. Then, the eluate will be submitted to mass spectrometry to identify potential targets. Data obtained through this project may provide a greater understanding of the mechanisms of action of the renal benefits of gliflozins in T2DM, HF, and CKD.