Dimethyloxalylglycine (DMOG) and the Caspase Inhibitor "Ac-LETD-CHO" Protect Neuronal ND7/23 Cells of Gluocotoxicity

Exp Clin Endocrinol Diabetes. 2021 Jun;129(6):420-428. doi: 10.1055/a-0919-4489. Epub 2019 Jun 11.

Abstract

It well known that long-lasting hyperglycaemia disrupts neuronal function and leads to neuropathy and other neurodegenerative diseases. The α-ketoglutarate analogue (DMOG) and the caspase-inhibitor "Ac-LETD-CHO are potential neuroprotective molecules. Whether their protections may also extend glucotoxicity-induced neuropathy is not known. Herein, we evaluated the possible cell-protective effects of DMOG and Ac-LETD-CHO against hyperglycaemia-induced reactive oxygen species and apoptosis in ND7/23 neuronal cells. The impact of glucotoxicity on the expression of HIF-1α and a panel of micro-RNAs of significance in hyperglycaemia and apoptosis was also investigated.ND7/23 cells cultured under hyperglycaemic conditions showed decreased cell viability and elevated levels of ROS production in a dose- and time-dependent manner. However, presence DMOG (500 µM) and/or Ac-LETD-CHO (50 µM) counteracted this effect and increase cell viability concomitant with reduction in ROS production, DNA damage and apoptosis. AcLETD-CHO suppressed hyperglycaemia-induced caspase 3 activation in ND7/23 cells. Both DMOG and Ac-LETD-CHO increased HIF-1α expression paralleled with the suppression of miR-126-5p, miR-128-3p and miR-181 expression and upregulation of miR-26b, 106a-5p, 106b-5p, 135a-5p, 135b-5p, 138-5p, 199a-5p, 200a-3p and 200c-3p expression.We demonstrate a mechanistic link for the DMOG and Ac-LETD-CHO protection against hyperglycaemia-induced neuronal dysfunction, DNA damage and apoptosis and thereby propose that pharmacological agents mimicking these effects may represent a promising novel therapy for the hyperglycaemia-induced neuropathy.

MeSH terms

  • Amino Acids, Dicarboxylic / pharmacology*
  • Apoptosis / drug effects*
  • Caspase Inhibitors / pharmacology*
  • Cells, Cultured
  • Diabetic Neuropathies / prevention & control*
  • Humans
  • Hyperglycemia / complications*
  • Hypoxia-Inducible Factor 1, alpha Subunit / drug effects*
  • Neurons / drug effects*
  • Neuroprotective Agents / pharmacology*

Substances

  • Amino Acids, Dicarboxylic
  • Caspase Inhibitors
  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Neuroprotective Agents
  • oxalylglycine