Title:Inhibition of Histone Deacetylase 6 Protects Hippocampal Cells Against Mitochondria-mediated Apoptosis in a Model of Severe Oxygen-glucose Deprivation
Volume: 19
Issue: 9
Author(s): Panpan Chang, Yuzi Tian, Aaron M. Williams, Umar F. Bhatti, Baoling Liu, Yongqing Li*Hasan B. Alam*
Affiliation:
- Department of Surgery, University of Michigan, Ann Arbor, Michigan,United States
- Department of Surgery, University of Michigan, Ann Arbor, Michigan,United States
Keywords:
Histone deacetylase 6, oxygen-glucose deprivation, neurons, mitochondria membrane potential,
apoptosis, HT22 cells.
Abstract:
Background: Histone deacetylase (HDAC) 6 inhibitors have demonstrated
significant protective effects in traumatic injuries. However, their roles in neuroprotection
and underlying mechanisms are poorly understood. This study sought to investigate the
neuroprotective effects of Tubastatin A (Tub-A), an HDAC6 inhibitor, during oxygenglucose
deprivation (OGD) in HT22 hippocampal cells.
Methods: HT22 hippocampal cells were exposed to OGD. Cell viability and cytotoxicity
were assessed by cell counting kit-8 (CCK-8) and lactate dehydrogenase (LDH) release
assay. Cellular apoptosis was assessed by Terminal deoxynucleotidyl transferase dUTP
nick end labeling (TUNEL) assay. Mitochondria membrane potential was detected using
JC-1 dye. Expressions of acetylated α-tubulin, α-tubulin, cytochrome c, VDAC, Bax, Bcl-
2, cleaved caspase 3, phosphorylated Akt, Akt, phosphorylated GSK3β and GSK3β
were analyzed by Western blot analysis.
Results: Tub-A induced acetylation of α-tubulin, demonstrating appropriate efficacy.
Tub-A significantly increased cell viability and attenuated LDH release after exposure to
OGD. Furthermore, Tub-A treatment blunted the increase in TUNEL-positive cells
following OGD and preserved the mitochondrial membrane potential. Tub-A also
attenuated the release of cytochrome c from the mitochondria into the cytoplasm and
suppressed the ratio of Bax/Bcl-2 and cleaved caspase 3. This was mediated, in part, by
the increased phosphorylation of Akt and GSK3β signaling pathways.
Conclusion: HDAC 6 inhibition, using Tub-A, protects against OGD-induced injury in
HT22 cells by modulating Akt/GSK3β signaling and inhibiting mitochondria-mediated
apoptosis.
