Loss of serine/threonine protein kinase 25 in retinal ganglion cells ameliorates high glucose-elicited damage through regulation of the AKT-GSK-3β/Nrf2 pathway

Biochem Biophys Res Commun. 2022 Apr 16:600:87-93. doi: 10.1016/j.bbrc.2022.02.044. Epub 2022 Feb 12.

Abstract

Serine/threonine protein kinase 25 (STK25) has critical importance for diabetic complications. However, whether STK25 has a link with diabetic retinopathy is not clearly understood. The damages of retinal ganglion cells (RGCs) caused by high glucose (HG) is a critical determinant for the onset of diabetic retinopathy. Herein, this work focused on assessing the possible role of STK25 in HG-evoked damage to RGCs. An expression abundance of STK25 was occurred in RGCs challenged with HG. STK25 loss lowered the deleterious effects on RGCs, including apoptosis, oxidative stress and inflammation. SKT25 silencing strengthened the activation of nuclear factor erythroid-2-related factor 2 (Nrf2) pathway in HG-challenged RGCs. Moreover, the inhibition of STK25 restored the phosphorylation of AKT and glycogen synthase kinase-3β (GSK-3β) in HG-challenged RGCs, whereas limiting AKT decreased the motivating effects of STK25 inhibition on the Nrf2 pathway. Additionally, the beneficial effects of STK25 inhibition on HG injuries were also reversed via the inhibition of Nrf2. Based on these observations, our work suggests that the inhibition of STK25 is protective for RGCs suffering HG injuries, which is achieved by effects on the AKT-GSK-3β/Nrf2 pathway. STK25 may participate in the onset of diabetic retinopathy by affecting HG-evoked damages of RGCs.

Keywords: Diabetes; High glucose; Inflammation; Nrf2; Oxidative stress; Retinal ganglion cells.

MeSH terms

  • Apoptosis
  • Diabetic Retinopathy* / metabolism
  • Diabetic Retinopathy* / pathology
  • Glucose / administration & dosage
  • Glucose / metabolism
  • Glycogen Synthase Kinase 3 beta* / metabolism
  • Humans
  • Intracellular Signaling Peptides and Proteins* / metabolism
  • NF-E2-Related Factor 2* / metabolism
  • Oxidative Stress
  • Protein Serine-Threonine Kinases*
  • Proto-Oncogene Proteins c-akt* / metabolism
  • Retinal Ganglion Cells* / metabolism
  • Retinal Ganglion Cells* / pathology
  • Signal Transduction

Substances

  • Glucose
  • Glycogen Synthase Kinase 3 beta
  • Intracellular Signaling Peptides and Proteins
  • NF-E2-Related Factor 2
  • NFE2L2 protein, human
  • Protein Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt
  • STK25 protein, human