c-Jun N-Terminal Kinase Inhibition Induces Mitochondrial Oxidative Stress and Decreases Survival in Human Neural Stem Progenitors

2018 ◽  
Vol 40 (4) ◽  
pp. 312-324
Author(s):  
Neha Sharma ◽  
Lisamarie Moore ◽  
Shravanthi Chidambaram ◽  
Nicholas W. Colangelo ◽  
Sonia M. de Toledo ◽  
...  
Keyword(s):  
Stem Cells ◽  
Membrane Potential ◽  
Neural Stem Cells ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Redox Homeostasis ◽  
Survivin Expression ◽  
Cell Functions ◽  
Brain Functions ◽  
Redox Environment

Neural stem cells are attracting enormous attention in regenerative medicine due to their ability to self-renew and differentiate into the cell lineages that constitute the central nervous system. However, little is known about the mechanism underlying the regulation of their redox environment, which is essential for homeostatic cellular functions. The redox-modulated c-Jun N-terminal kinases (JNK) are a molecular switch in stress signal transduction and are involved in numerous brain functions. Using a selective but broad-spectrum inhibitor of JNK 1/2/3, we investigated the role of JNK in regulating the levels of reactive oxygen species in mitochondria, mitochondrial membrane potential, viability, proliferation and lineage alterations in human H9-derived neural stem/progenitor cells (NSPs). Relative to diluent control, incubation of the NSPs for 24 h with SP600125, an anthrapyrazolone inhibitor of JNK, resulted in increased abundance of mitochondrial superoxide radicals (p < 0.05), concomitant with decreases in mitochondrial membrane potential (p < 0.001), while maintaining a consistent and stable mitochondrial mass. Whereas H9-derived NSPs collectively express Nestin, a marker for neural stem cells, a panel of cell surface markers analyzed by flow cytometry revealed that they are a heterogeneous population that sustains this diversity after JNK inhibition. In addition, the levels of nuclear forkhead homeobox type O3a (FoxO3a), a regulator of redox homeostasis, decreased, which was associated with a decrease in overall cell viability as measured by Annexin V staining (p < 0.001), and supported by an increased level of cleaved Poly-ADP-ribose polymerase and decreased survivin expression. However, staining with the proliferation marker, Ki67, revealed the presence of a significant percentage of proliferating cells in the treated population. Together, the results support a role for JNK in the redox-homeostasis and fate of NSPs. Identifying regulators of the cellular redox environment will enhance our understanding of the mechanisms that modulate neural stem cell functions and optimize therapeutic applications targeting JNK.

scholarly journals Globular Adiponectin Inhibits the Apoptosis of Mesenchymal Stem Cells Induced by Hypoxia and Serum Deprivation via the AdipoR1-Mediated Pathway

2016 ◽  
Vol 38 (3) ◽  
pp. 909-925 ◽  
Author(s):  
Xia-Qiu Tian ◽  
Yue-Jin Yang ◽  
Qing Li ◽  
Pei-Sen Huang ◽  
Xiang-Dong Li ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Caspase 3 ◽  
Serum Deprivation ◽  
Dependent Manner ◽  
Compound C ◽  
Globular Adiponectin

Background/Aims: Poor viability of transplanted mesenchymal stem cells (MSCs) within the ischemic heart limits their therapeutic potential for cardiac repair. Globular adiponectin (gAPN) exerts anti-apoptotic effects on several types of stem cells. Herein, we investigated the effect of gAPN on the MSCs against apoptosis induced by hypoxia and serum deprivation (H/SD). Methods: MSCs exposed to H/SD conditions were treated with different concentrations of gAPN. To identify the main type of receptor, MSCs were transfected with siRNA targeting adiponectin receptor 1 or 2 (AdipoR1 or AdipoR2). To elucidate the downstream pathway, MSCs were pre-incubated with AMPK inhibitor Compound C. Apoptosis, caspase-3 activity and mitochondrial membrane potential were evaluated. Results: H/SD-induced MSCs apoptosis and caspase-3 activation were attenuated by gAPN in a concentration-dependent manner. gAPN increased Bcl-2 and decreased Bax expressions. The loss of mitochondrial membrane potential induced by H/SD was also abolished by gAPN. The protective effect of gAPN was significantly attenuated after the knockdown of AdipoR1 rather than AdipoR2. Moreover, Compound C partly suppressed the anti-apoptotic effect of gAPN. Conclusions: gAPN inhibits H/SD-induced apoptosis in MSCs via AdipoR1-mediated pathway, possibly linked to the activation of AMPK. gAPN may be a novel survival factor for MSCs in the ischemic engraftment environment.

scholarly journals CoCl2 induces apoptosis via a ROS-dependent pathway and Drp1-mediated mitochondria fission in periodontal ligament stem cells

2018 ◽  
Vol 315 (3) ◽  
pp. C389-C397 ◽  
Author(s):  
Yuting He ◽  
Xueqi Gan ◽  
Ling Zhang ◽  
Beilei Liu ◽  
Zhuoli Zhu ◽  
...  
Keyword(s):  
Stem Cells ◽  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Periodontal Ligament ◽  
Mitochondrial Membrane ◽  
Mitochondrial Fission ◽  
Orthodontic Appliances ◽  
Dependent Manner ◽  
Periodontal Ligament Stem Cells ◽  
Atp Level

Oxygen deficiency is associated with various oral diseases, including chronic periodontitis, age-related alveolar bone loss, and mechanical stress-linked cell injury from orthodontic appliances. Nevertheless, our understanding of the impact of hypoxia on periodontal tissues and its biochemical mechanism is still rudimentary. The purpose of this research was to elucidate the effects of hypoxia on the apoptosis of human periodontal ligament stem cells (PDLSCs) in vitro and the underlying mechanism. Herein, we showed that cobalt chloride (CoCl2) triggered cell dysfunction in human PDLSCs in a concentration-dependent manner and resulted in cell apoptosis and oxidative stress overproduction and accumulation in PDLSCs. In addition, CoCl2 promoted mitochondrial fission in PDLSCs. Importantly, CoCl2 increased the expression of dynamin-related protein 1 (Drp1), the major regulator in mitochondrial fission, in PDLSCs. Mitochondrial division inhibitor-1, pharmacological inhibition of Drp1, not only inhibited mitochondrial fission but also protected against CoCl2-induced PDLSC dysfunction, as shown by increased mitochondrial membrane potential, increased ATP level, reduced reactive oxygen species (ROS) level, and decreased apoptosis. Furthermore, N-acety-l-cysteine, a pharmacological inhibitor of ROS, also abolished CoCl2-induced expression of Drp1 and protected against CoCl2-induced PDLSC dysfunction, as shown by restored mitochondrial membrane potential, ATP level, inhibited mitochondrial fission, and decreased apoptosis. Collectively, our data provide new insights into the role of the ROS-Drp1-dependent mitochondrial pathway in CoCl2-induced apoptosis in PDLSCs, indicating that ROS and Drp1 are promising therapeutic targets for the treatment of CoCl2-induced PDLSC dysfunction.

Abstract 335: Exercise Protects the Heart by Preserving Mitochondrial Membrane Potential During Early Reperfusion

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Rick J Alleman ◽  
Hetal D Patel ◽  
Fatiha Moukdar ◽  
David A Brown
Keyword(s):  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Fluorescence Intensity ◽  
Mitochondrial Membrane ◽  
Ischemia Reperfusion ◽  
Redox Homeostasis ◽  
Respiratory Control ◽  
Treadmill Running ◽  
Early Reperfusion

Exercise evokes adaptations intrinsic to the myocardium that protect against ventricular arrhythmia, yet the underlying mechanisms are not completely understood. We have previously shown that the transition to arrhythmia occurs concomitant with a collapse in mitochondrial membrane potential (ΔΨm). As our previous studies indicated that exercise preserves intracellular redox homeostasis, which directly influences mitochondrial energetics, we hypothesized that rats exposed to exercise (Ex, 10 d of treadmill running) would be protected against reperfusion arrhythmia via better maintenance of ΔΨm. To fully understand the temporal relationship between ΔΨm and cardiac electrical activity, two-photon microscopy images (using the fluorescent probe TMRM) and volume-conducted electrocardiogram were simultaneously recorded. Langendorff-perfused hearts underwent 40/30 min of ischemia/reperfusion. Exercise lowered the incidence of arrhythmia, with 3 of 8 Ex hearts experiencing tachycardia or fibrillation compared to 7 of 8 sedentary (Sed) hearts. Ex prevented the collapse of ΔΨm during the first 10 min of reperfusion (74±6.4% v 57±1.5% of baseline fluorescence intensity; P<0.05). To gain a more comprehensive understanding of energetics throughout the heterogeneous mitochondrial population, we then measured mean TMRM fluorescence intensity in isolated ventricular mitochondria harvested after reperfusion using flow cytometry (n=100,000 events per group). Interestingly, mean fluorescence intensity for ΔΨm was similar in Ex and Sed mitochondria (278±33 v 309 ±44 AU, respectively). Mitochondrial respiratory control ratios were also similar in Ex and Sed (9.03±0.70 v 9.00±0.92, respectively). Taken together, the isolated mitochondrial assessment did not reflect what was observed in vivo. This suggests that either intracellular factors influenced in vivo mitochondrial energetics, or our isolated mitochondria may have been enriched with predominantly healthy mitochondria. Our studies demonstrate for the first time that exercise prevents electrical dysfunction following an ischemic insult through better preservation of mitochondrial energetics, and that this preservation is only observed in the intact organ.

scholarly journals Shikonin Enhances the Antitumor Effect of Cabazitaxel in Prostate Cancer Stem Cells and Reverses Cabazitaxel Resistance by Inhibiting the Expression of ABCG2 and ALDH3A1

2020 ◽  
Author(s):  
Lili Wang ◽  
Birgit Stadlbauer ◽  
Chen Lyu ◽  
Alexander Buchner ◽  
Heike Pohla
Keyword(s):  
Prostate Cancer ◽  
Stem Cells ◽  
Membrane Potential ◽  
Cancer Stem Cells ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Antitumor Effect ◽  
Migration And Invasion ◽  
Drug Resistant ◽  
Resistant Cells

Abstract Background: Cancer stem cells (CSCs) are a small population among cancer cells, defined as capable of self-renewal, and driving tumor growth, metastasis, and therapeutic relapse. The development of therapeutic strategies to target CSCs is of great importance to prevent tumor metastasis and relapse. Increasing evidence shows that shikonin has inhibiting effects on CSCs. This study was to determine the effect of shikonin on prostate CSCs, and on drug resistant cells.Methods: Sphere formation assay was used to enrich prostate CSCs. The effect of shikonin on viability, proliferation, migration, and invasion was studied. Typical CSCs markers were analyzed by flow cytometry and RT-qPCR. The cytotoxic mechanism of shikonin was analyzed by staining for annexin V, reactive oxygen species (ROS) and mitochondrial membrane potential. To study the effect of shikonin on drug resistant cells a cabazitaxel resistant cell line was established.Results: Shikonin inhibited the viability, proliferation, migration, and invasion of prostate CSCs. Shikonin enhanced the antitumor effect of cabazitaxel, which is a second-line chemotherapeutic drug in advanced prostate cancer. Shikonin induced apoptosis through generating ROS and disrupting the mitochondrial membrane potential. Furthermore, shikonin suppressed the expression of ALDH3A1 and ABCG2 in prostate CSCs, which are two markers related to drug-resistance. When inhibiting the expression of ABCG2 and ALDH3A1, the cabazitaxel resistant cells acquired more sensibility to cabazitaxel. Conclusions: Shikonin enhances the cytotoxic activity of cabazitaxel in prostate CSCs and reverses the cabazitaxel-resistant state.

Heterogeneity of Mitochondrial Membrane Potential: A Novel Tool to Isolate and Identify Cancer Stem Cells from a Tumor Mass?

2010 ◽  
Vol 7 (1) ◽  
pp. 153-160 ◽  
Author(s):  
Xiao-Qun Ye ◽  
Guang-Hui Wang ◽  
Gui-Jun Huang ◽  
Xiu-Wu Bian ◽  
Gui-Sheng Qian ◽  
...  
Keyword(s):  
Stem Cells ◽  
Membrane Potential ◽  
Cancer Stem Cells ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Tumor Mass

scholarly journals Inhibition of phosphodiesterase - 10A by Papaverine protects human cortical neurons from quinolinic acid induced oxidative stress and synaptic proteins alterations

2020 ◽  
Author(s):  
Abid Bhat ◽  
Vanessa Tan ◽  
Benjamin Heng ◽  
Musthafa M. Essa ◽  
Saravana B. Chidambaram ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Quinolinic Acid ◽  
Cortical Neurons ◽  
Mitochondrial Membrane ◽  
Critical Role ◽  
Synaptic Proteins ◽  
Intracellular Camp ◽  
Brain Functions

AbstractPhosphodi esterase-10A (PDE10A) hydrolyse the secondary messengers cGMP and cAMP which play critical role in neurodevelopment and brain functions. PDE10A is linked to progression of neurodegenerative diseases like Alzheimer’s, Parkinson’s, Huntington’s diseases etc and a critical role in cognitive functions. The present study was undertaken to determine the possible neuroprotective effects and the associated mechanism of papaverine (PAP) against quinolinic acid (QUIN) induced excitotoxicity using human primary cortical neurons. Cytotoxicity potential of PAP was analysed using MTS assay. Reactive oxygen species (ROS) and mitochondrial membrane potential were measured by DCF-DA and JC10 staining, respectively. Caspase 3/7 and cAMP levels using ELISA kits. Effect of PAP on the CREB, BNDF and synaptic proteins such as SAP-97, synaptophysin, synapsin-I, PSD-95 expression was analysed by Western blotting technique. Pre-treatment with PAP increased intracellular cAMP and nicotinamide adenine dinucleotide (NAD+) levels, restored mitochondrial membrane potential (ΔΨm), and decreased ROS and caspase3/7 content in QUIN exposed neurons. PAP up-regulated CREB and BDNF, and synaptic proteins expression. In summary, these data indicate that PDE10A involves in QUIN mediated neurotoxicity and its inhibition can elicit neuroprotection by reducing the oxidative stress and protecting synaptic proteins via upregulation of cAMP signalling cascade.

scholarly journals Biochemical re-programming of human dermal stem cells to neurons by increasing mitochondrial membrane potential

2018 ◽  
Vol 26 (6) ◽  
pp. 1048-1061 ◽  
Author(s):  
He Liu ◽  
Zhaoyue He ◽  
Simon Leonhard April ◽  
Marcel Philipp Trefny ◽  
Jean-Sébastien Rougier ◽  
...  
Keyword(s):  
Stem Cells ◽  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane
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