scholarly journals Drosophila Histone Deacetylase 6 Protects Dopaminergic Neurons against α-Synuclein Toxicity by Promoting Inclusion Formation

2010 ◽  
Vol 21 (13) ◽  
pp. 2128-2137 ◽  
Author(s):  
Guiping Du ◽  
Xiang Liu ◽  
Xinping Chen ◽  
Mei Song ◽  
Yan Yan ◽  
...  
Keyword(s):  
Retinal Degeneration ◽  
Histone Deacetylase ◽  
Dopaminergic Neurons ◽  
Critical Role ◽  
Ectopic Expression ◽  
Common Mechanism ◽  
Histone Deacetylase 6 ◽  
Inclusion Formation ◽  
Progressive Degeneration ◽  
First Time

Parkinson's disease (PD) is associated with progressive degeneration of dopaminergic (DA) neurons. We report for the first time that the Drosophila histone deacetylase 6 (dHDAC6) plays a critical role in the protection of DA neurons and the formation of α-synuclein inclusions by using a Drosophila PD model constructed by ectopic expression of human α-synuclein. Depletion of dHDAC6 significantly enhances the effects caused by ectopic expression of α-synuclein, namely, loss of DA neurons, retinal degeneration, and locomotor dysfunction. Expression of α-synuclein in the DA neurons leads to fewer inclusions in the brains of dHDAC6 mutant flies than in wild-type flies. Conversely, overexpression of dHDAC6 is able to suppress the α-synuclein–induced DA neuron loss and retinal degeneration and promote inclusion formation. Furthermore, mutation of dHDAC6 reinforces the accumulation of oligomers that are suggested to be a toxic form of α-synuclein. We propose that α-synuclein inclusion formation in the presence of dHDAC6 protects DA neurons from being damaged by oligomers, which may uncover a common mechanism for synucleinopathies.

Abstract 502: Inhibition of Histone Deacetylase 6 Protects Human Induced Pluripotent Stem Cells-derived Cardiomyocytes Through Inhibition of Autophagy

2020 ◽  
Vol 127 (Suppl_1) ◽  
Author(s):  
Narasimman Gurusamy ◽  
SHEEJA RAJASINGH ◽  
Vinoth Sigamani ◽  
Shivaani Kirankumar ◽  
Jayavardini Vasanthan ◽  
...  
Keyword(s):  
Stem Cells ◽  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Induced Pluripotent Stem Cells ◽  
Histone Deacetylase ◽  
Pluripotent Stem Cells ◽  
Histone Deacetylase 6 ◽  
Hdac6 Inhibitor ◽  
Induced Pluripotent ◽  
First Time

Introduction: Autophagy is known to play an important role in mediating cardiac hypertrophy. However, the mechanism is poorly understood. Since the protein histone deacetylase 6 (HDAC6) contributes to cardiac dysfunction in response to angiotensin II (AngII) signaling, we have examined the role of HDAC6 inhibitor tubastatin A (TBA) in AngII-induced remodeling in human induced pluripotent stem cells-derived cardiomyocytes (iCMCs). Hypothesis: We hypothesize that the inhibition of HDAC6 protects iCMCs from AngII-induced cardiac hypertrophy through inhibition of autophagy. Methods and Results: We have generated and characterized induced pluripotent stem cells from human adult skin fibroblasts and subsequently differentiated them into iCMCs. Treatment with 10 μM angiotensin II for 24 hrs increased the HDAC6 activity and lead to hypertrophy in iCMCs. The AngII-induced hypertrophy, and the excessive contractility in iCMCs were reversed by the inhibition of HDAC6 with TBA (1 μM for 24 hours). The number of LC3-positive iCMCs, and the mRNA and the protein expression of autophagic genes Beclin-1, LC3, and p62 were increased by the presence of AngII, and the anti-autophagic gene Bcl2 was decreased by AngII. The inhibition of HDAC6 with TBA reversed the AngII-mediated changes in the autophagic genes expressions in iCMCs. Autophagic vacuoles were identified with monodansylcadaverine (MDC, green) and lysosomes with LysoTracker (red) (Fig. 1A) . The number of autophagolysosomes were increased by AngII, and this was decreased with TBA in iCMCs (Fig. 1B) . Conclusions: Our report indicates for the first time that the AngII-induced cardiac hypertrophy-mediated autophagy is effectively inhibited by the suppression of HDAC6 in human iCMCs.

Histone deacetylase 6– HDAC6– a new regulator of glucocorticoid receptor-mediated metabolic processes

2010 ◽  
Vol 5 (S 01) ◽  
Author(s):  
R Winkler ◽  
M Clemenz ◽  
M Bloch ◽  
A Foryst-Ludwig ◽  
C Böhm ◽  
...  
Keyword(s):  
Glucocorticoid Receptor ◽  
Histone Deacetylase ◽  
Histone Deacetylase 6 ◽  
Metabolic Processes

Non-Plasmonic SERS with Silicon: Is It Really Safe? New Insights into Opto-Thermics of Core/Shell Microbeads

2018 ◽  
Author(s):  
Nicolò Bontempi ◽  
Irene Vassalini ◽  
Stefano Danesi ◽  
Matteo Ferroni ◽  
Paolo Colombi ◽  
...  
Keyword(s):  
Critical Role ◽  
Raman Laser ◽  
Core Shell ◽  
Thermal Coupling ◽  
Melting Points ◽  
Experimental Proof ◽  
Weakly Coupled ◽  
Light Management ◽  
Laser Sources ◽  
First Time

<p>Here we investigate for the first time the opto-thermal behavior of SiO<sub>2</sub>/Si core/shell microbeads (Si-rex) irradiated with three common Raman laser sources (lambda=532, 633, 785 nm) under real working conditions. We obtained an experimental proof of the critical role played by bead size and aggregation in heat and light management, demonstrating that in the case of strong opto-thermal coupling the temperature can exceed that of the melting points of both core and shell components. In addition, we also show that weakly coupled beads can be utilized as stable substrates for plasmon-free SERS experiments.</p>

Inhibition of Histone Deacetylase 6 Protects Hippocampal Cells Against Mitochondria-mediated Apoptosis in a Model of Severe Oxygen-glucose Deprivation

2019 ◽  
Vol 19 (9) ◽  
pp. 673-682 ◽  
Author(s):  
Panpan Chang ◽  
Yuzi Tian ◽  
Aaron M. Williams ◽  
Umar F. Bhatti ◽  
Baoling Liu ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Cytochrome C ◽  
Cell Viability ◽  
Histone Deacetylase ◽  
Caspase 3 ◽  
Cell Counting ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Histone Deacetylase 6 ◽  
Phosphorylated Akt ◽  
Ldh Release

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.

scholarly journals Nutraceutical Supplementation Ameliorates Visual Function, Retinal Degeneration, and Redox Status in rd10 Mice

Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1033
Author(s):  
Lorena Olivares-González ◽  
Sheyla Velasco ◽  
Isabel Campillo ◽  
David Salom ◽  
Emilio González-García ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Retinal Degeneration ◽  
Antioxidant Properties ◽  
Photoreceptor Cells ◽  
Redox Status ◽  
Inherited Retinal Dystrophies ◽  
Stress Markers ◽  
Retinal Dystrophies ◽  
Progressive Degeneration ◽  
Light Stimuli

Background: Retinitis pigmentosa (RP) is a group of inherited retinal dystrophies characterized by progressive degeneration of photoreceptor cells. Ocular redox status is altered in RP suggesting oxidative stress could contribute to their progression. In this study, we investigated the effect of a mixture of nutraceuticals with antioxidant properties (NUT) on retinal degeneration in rd10 mice, a model of RP. Methods: NUT was orally administered to rd10 mice from postnatal day (PD) 9 to PD18. At PD18 retinal function and morphology were examined by electroretinography (ERG) and histology including TUNEL assay, immunolabeling of microglia, Müller cells, and poly ADP ribose polymers. Retinal redox status was determined by measuring the activity of antioxidant enzymes and some oxidative stress markers. Gene expression of the cytokines IL-6, TNFα, and IL-1β was assessed by real-time PCR. Results: NUT treatment delayed the loss of photoreceptors in rd10 mice partially preserving their electrical responses to light stimuli. Moreover, it ameliorated redox status and reduced inflammation including microglia activation, upregulation of cytokines, reactive gliosis, and PARP overactivation. Conclusions: NUT ameliorated retinal functionality and morphology at early stages of RP in rd10 mice. This formulation could be useful as a neuroprotective approach for patients with RP in the future.

Synthesis of an azadioxa-planar triphenylborane and investigation of its structural and photophysical properties

2021 ◽  
Author(s):  
Y. Kitamoto ◽  
K. Oda ◽  
K. Ogino ◽  
K. Hiyama ◽  
H. Kita ◽  
...  
Keyword(s):  
Photophysical Properties ◽  
Critical Role ◽  
Molecular Properties ◽  
Bridging Groups ◽  
First Time

An azadioxa-planar triphenylborane was synthesized for the first time and it was found that bridging groups have a critical role in changing its molecular properties.

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