Investigation of TRPM2 cation channel activation in PTZ-induced SH-SY5Y cells by patch-clamp technique: Regulatory role of valproic acid


Creative Commons License

Ahlatcı A., Bektaş M., Tülüce Y., Yıldızhan K.

7th International Brain Research School, Isparta, Turkey, 27 June - 03 July 2022, vol.14, no.4, pp.19

  • Publication Type: Conference Paper / Summary Text
  • Volume: 14
  • City: Isparta
  • Country: Turkey
  • Page Numbers: pp.19
  • Istanbul University Affiliated: Yes

Abstract

Investigation of TRPM2 cation channel activation in PTZ-induced SH-SY5Y cells by

patch-clamp technique: Regulatory role of valproic acid.

Adem AHLATCI1

, Muhammet BEKTAŞ1

, Yasin TÜLÜCE2

, Kenan YILDIZHAN3

1Department of Biophysics, Istanbul Faculty of Medicine, Istanbul University, Istanbul,

Turkey.

2Department of Medical Biology, Faculty of Medicine, Van Yuzuncu Yil University, Van,

Turkey.

3Department of Biophysics, Faculty of Medicine, Van Yuzuncu Yil University, Van, Turkey.

Abstract

Neurotoxicity is the event that neurons are damaged by natural or artificial toxic substances.

Pentylenetetrazole (PTZ) is a neurotoxic substance and is used to produce experimental

neurotoxicity. Transient Receptor Potential Melastatin 2 (TRPM2) Channel is a non-selective

cation channel activated by adenosine diphosphoribose (ADPR), calcium ion (Ca2+) and

reactive oxygen species and nitrogen species. It is inactivated by N-(p-amylcinnamoyl)

anthranilic acid (ACA). Valproic acid (VPA) is a short-chain fatty acid in the chemical structure

of N-dipropyl acetic acid, it is used as various anticonvulsants and mood stabilizers, especially

in psychiatric and neurological cases. Studies have shown that valproic acid blocks voltagegated sodium or calcium channels (Bowden 2003), but its effect on the TRPM2 channel in the

neuron cell line has not yet been clarified.

SH-SY5Y cells were divided into five groups; control, control + ADPR, PTZ (30 µM for 24

hours), VPA (1 mM for 24 hours), and PTZ + VPA (30 µM for 24 hours and 1 mM for 24

hours) (Taskiran et. al., 2021). The patch-clamp technique was used to observe the activation

of the TRPM2 channel and the protective effect of VPA in the neurotoxicity model created by

PTZ. In the study, ADPR was used as an agonist and ACA as an antagonist for TRPM2

stimulation in SH-SY5Y cells (Yıldızhan and Nazıroğlu 2020). The whole-cell mode patchclamp record showed us that in the ADPR-stimulated groups, the intracellular Ca2+ flow was

highest in the PTZ group compared to the other groups. While no intracellular Ca2+ flow was

observed in the VPA group, intracellular Ca2+ flow was significantly inhibited in the PTZ+VPA

group compared to the PTZ group.

In conclusion, in the electrophysiological study using the patch-clamp technique, we observed

that VPA has a regulatory effect on TRPM2 channel currents in PTZ-induced SH-SY5Y cells.