7th International Brain Research School, Isparta, Turkey, 27 June - 03 July 2022, vol.14, no.4, pp.19
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, Türkiye.
2Department of Medical Biology, Faculty of Medicine,
Van Yuzuncu Yil University, Van, Türkiye.
3Department of Biophysics, Faculty of Medicine, Van
Yuzuncu Yil University, Van, Türkiye.
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 voltage-gated
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
patch-clamp record showed us that in the ADPRstimulated
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.
Keywords: Epilepsy; TRPM2 channel: Valproic acid;
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Taskiran AS, Ergul M, Gunes H, Ozturk A, Sahin B, Ozdemir E. 2021.
The Effects of Proton Pump Inhibitors (Pantoprazole) on
Pentylenetetrazole-Induced Epileptic Seizures in Rats and
Neurotoxicity in the SH-SY5Y Human Neuroblastoma Cell
Line. Cell Mol Neurobiol. 41(1):173-183. doi: 10.1007/s10571-
Yıldızhan K, Nazıroğlu M. 2020. Glutathione Depletion and
Parkinsonian Neurotoxin MPP+-Induced TRPM2 Channel
Activation Play Central Roles in Oxidative Cytotoxicity and
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