Sirtuin 6 affects glucose reabsorption and gluconeogenesis in type 1 diabetes via FoxO1

Mol Cell Endocrinol. 2022 May 1:547:111597. doi: 10.1016/j.mce.2022.111597. Epub 2022 Feb 11.

Abstract

Aim: The purpose of this study was to explore the expression changes of Sirtuin 6 in diabetic renal tissues and the molecular mechanisms affecting renal tubular gluconeogenesis and reabsorption.

Methods: The type 1 diabetic C57BL/6 mice model as well as high glucose cultured proximal tubular cells and cell lines were established. Sirt6 siRNA, the SGLT2 inhibitor (dapagliflozin), and insulin were pre-treated to make Sirtuin 6 levels, gluconeogenesis, and reabsorption changes. Immunofluorescence was used for Sirtuin 6 renal localization, and molecular biological detection was adopted for transcription factors, FoxO1, transporters (SGLT2 and GLUT2) as well as rate-limiting enzyme. Nuclear/plasma proteins were extracted to detect Sirtuin 6 and FoxO1 levels in the subcellular structure.

Results: Sirtuin 6 was decreased in STZ-induced diabetic renal outer medulla, and lower both in high glucose-induced primary proximal tubular cells and cell lines. Sirtuin 6 reversed the glucose reabsorption and gluconeogenesis effect via regulating FoxO1 and affecting nuclear translocation of FoxO1 in high glucose-induced proximal tubular cells.

Conclusion: Sirtuin 6 affects renal glucose reabsorption and gluconeogenesis in type 1 diabetes by regulating FoxO1 nuclear import.

Keywords: Gluconeogenesis; Glucose reabsorption; Sirtuin 6; Type 1 diabetes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Diabetes Mellitus, Type 1* / metabolism
  • Forkhead Box Protein O1* / metabolism
  • Gluconeogenesis
  • Glucose* / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Sirtuins* / genetics

Substances

  • Forkhead Box Protein O1
  • Foxo1 protein, mouse
  • Sirt6 protein, mouse
  • Sirtuins
  • Glucose