Exercise delays neutrophil apoptosis by a G-CSF-dependent mechanism

The aim of the study was to determine whether exercise affects neutrophil apoptosis and to characterize the underlying mechanisms. Using annexin V labeling, neutrophil apoptosis was measured using flow cytometry after various bouts of exercise (marathon run, concentric/eccentric treadmill exercise, moderate/intensive resistance training) and in vitro conditions. Similarly, apoptosis-related markers as death receptors/ligands and mitochondrial membrane potential were detected. Furthermore, concentrations of intracellular free calcium and glutathione were measured using spectrofluorometry. After both marathon run and intensive laboratory exercise tests, neutrophil apoptosis was delayed. Furthermore, neutrophils mitochondrial membrane potential and death receptor/ligand expression were not affected by exercise. Apoptosis delay was accompanied under some exercise conditions by enhanced intracellular calcium transients and decreased glutathione levels. A delay of spontaneous apoptosis in vitro could be induced by incubation of neutrophils in postexercise serum. Heating of postexercise serum abolished the apoptosis delaying effect. In vitro stimulation of resting neutrophils with granulocyte-colony-stimulating factor (G-CSF) and C-reactive protein resulted in apoptosis delay too. Addition of anti-G-CSF antibody to postexercise serum was also effective in reversing its apoptosis-delaying effect. Exercise-induced mobilization of neutrophils is associated with a delay of apoptosis. This fundamental process seems to maintain exercise-induced neutrophilia and to contribute to the alerting and activation of the nonadaptive immune system known from other inflammatory conditions. An important extracellular trigger of apoptosis delay during exercise conditions seems to be G-CSF; intracellular processes may include calcium and redox signaling.

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Does Cryopreservation of Ovarian Tissue Affect the Distribution and Function of Germinal Vesicle Oocytes Mitochondria?

BioMed Research International ◽

10.1155/2013/489032 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Mojdeh Salehnia ◽

Virpi Töhönen ◽

Saeed Zavareh ◽

Jose Inzunza

Keyword(s):

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Laser Scanning ◽

Ovarian Tissue ◽

Germinal Vesicle ◽

Free Calcium ◽

Atp Content ◽

Fertilization Rates

The aim of this study was to evaluate mitochondrial alteration and ATP content of germinal vesicle (GV) oocytes isolated from fresh and vitrified ovaries. After superovulation, the ovaries from adult mice were collected and divided into control and vitrified groups. GV oocytes were isolated mechanically from each group. Half were cultured for 24 hours and their maturation was assessed. Metaphase II oocytes were collected and submitted toin vitrofertilization and their fertilization rates and development to the blastocyst stage were evaluated. In the remaining GV oocytes, ATP levels were quantified, and mitochondrial distribution, mitochondrial membrane potential, and intracellular free calcium were detected with rhodamine 123, JC-1 and Flou-4 AM staining, using laser-scanning confocal microscopy. Maturation and fertilization rates of GV oocytes and the developmental rates of subsequent embryos were significantly lower in vitrified samples (P<0.05). The ATP content and Ca2+levels differed significantly in fresh and vitrified GV oocytes (P<0.05). Most mitochondria were seen as large and homogenous aggregates (66.6%) in fresh GV oocytes compared to vitrified oocytes (50%). No significant differences in mitochondrial membrane potential were found between the groups. The lower maturation and fertilization rates of GV oocytes from vitrified ovaries may be due to changes in their mitochondrial function and distribution.

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Flavopiridol Decreases Mcl-1 and Initiates Early Mitochondrial Damage in Chronic Lymphocytic Leukemia (CLL) Cells.

Blood ◽

10.1182/blood.v108.11.2098.2098 ◽

2006 ◽

Vol 108 (11) ◽

pp. 2098-2098

Author(s):

David M. Lucas ◽

Syed-Rehan A. Hussain ◽

Amy J. Johnson ◽

Lisa L. Smith ◽

Amy J. Wagner ◽

...

Keyword(s):

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mechanism Of Action ◽

Mitochondrial Membrane ◽

Tumor Lysis Syndrome ◽

Annexin V ◽

Caspase 8 ◽

Adapter Protein ◽

Tumor Lysis

Abstract We have noted impressive activity of the cyclin-dependent kinase inhibitor flavopiridol in advanced-stage CLL patients, including those with a deletion of chromosome 17p13. Using a novel, effective schedule of flavopiridol, substantial and sometimes dramatic evidence of tumor cell death is observed as early as 4–6 hours. This is accompanied by hyperkalemia, hyperphosphatemia, hypocalcemia, and dramatic elevation in LDH consistent with acute tumor lysis syndrome. Studies by several groups including our own have demonstrated that Mcl-1 protein and mRNA is down-regulated with flavopiridol. Mcl-1 is an important protein that contributes to mitochondrial membrane stability. We have therefore sought to determine the role of mitochondria disruption in the mechanism of action of flavopiridol. By flow cytometry using the voltage-sensitive dye JC-1, loss of mitochondrial membrane potential was detected in flavopiridol-treated whole blood as early as five hours, prior to the onset of annexin-V or propidium iodide staining. This is in contrast to in vitro studies using human serum, in which mitochondrial depolarization and annexin-V staining occurred simultaneously. In isolated CLL cells treated with flavopiridol in vitro, loss of mitochondrial membrane potential was not affected by inhibitors of caspases 8 or 9 or by the broad caspase inhibitor Z-VAD-fmk, although apoptosis was effectively blocked by Z-VAD-fmk and caspase-8 inhibitor, and to a lesser extent, caspase-9 inhibitor. Flavopiridol was also able to effectively induce apoptosis and mitochondrial membrane depolarization in Jurkat cell lines deficient in caspase-8 or its adapter protein FADD. Additionally, lymphoid cells overexpressing Bcl-2 are resistant to flavopiridol-mediated apoptosis relative to the vector control. This suggests there is not direct binding of flavopiridol or its metabolites to APAF-1 (cytosolic adapter protein) and apoptosome assembly, as this process is insensitive to Bcl-2 family proteins. Further mechanistic studies were undertaken using isolated liver mitochondria. While the electron transport system was not uncoupled in this system, potential mechanisms of mitochondrial injury in leukemic cells from CLL patients are currently under exploration. Taken together, these observations suggest that mitochondrial perturbation contributes significantly to the death process induced by flavopiridol. Further studies to identify the mechanism of mitochondrial perturbation will be essential to understanding flavopiridol’s mechanism of action and for predicting patients at risk for acute tumor lysis syndrome. (Support for this work was provided by the Samuel Waxman Foundation and the Leukemia & Lymphoma Society.)

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In vitro studies on the toxicity of isoniazid in different cell lines

Human & Experimental Toxicology ◽

10.1191/0960327103ht401oa ◽

2003 ◽

Vol 22 (11) ◽

pp. 607-615 ◽

Cited By ~ 31

Author(s):

Christina E Schwab ◽

Helga Tuschl

Keyword(s):

Cell Cycle ◽

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mammalian Cells ◽

Mitochondrial Membrane ◽

Annexin V ◽

Apoptotic Cells ◽

Lymphoma Cells ◽

Cytotoxicity Effects

The aim of the present study was to investigate in vitrothe mechanism of toxicity of isoniazid (-INH), the drug most widely used for treatment of tuberculosis. The human hepatoma line HepG2, the human lymphoblastoid line AHH-1 and the murine lymphoma cells YAC-1 were used as test systems. Active cell death (-apoptosis) and necrosis were detected by different flow cytometric methods: the binding of annexin V to the cell membrane and staining with propidium iodide (PI), the TUNEL assay for detection of DNA fragmentation and the occurrence of a sub G1 peak in cell cycle histograms. Mitochondrial membrane potential was analysed with the fluorescent probe JC-1. In addition to cytotoxicity, effects of INH on cell cycle were studied in HepG2 cells. The data of the present investigations indicate that INH induces cytotoxicity via apoptosis both in hepatoma and lymphoma cells. Twenty-four hours of application of INH in concentrations -26 mM led to a remarkable number of apoptotic cells positive for Annexin V. The induction of apoptosis was accompanied by a break down of the mitochondrial membrane potential and the occurrence of DNA strand breaks. At incubation times from 36 to 48 hours, a sub-G1 peak of late apoptotic cells was detected in cell cycle analysis. Furthermore, cell cycle studies showed a disruption of the cycle at low concentrations of INH which are only mildly cytotoxic. Thus the present study unequivocally demonstrated that INH induces cytotoxicity via apoptosis and can lead to a significant disturbance of the cell cycle in mammalian cells.

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Xiaoyaosan Decoction, a Traditional Chinese Medicine, Inhibits Oxidative-Stress-Induced Hippocampus Neuron Apoptosis In Vitro

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2012/489254 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 10

Author(s):

Zhen-zhi Meng ◽

Jing-hong Hu ◽

Jia-xu Chen ◽

Guang-xin Yue

Keyword(s):

Oxidative Stress ◽

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Low Dose ◽

Free Calcium ◽

High Dose ◽

Hippocampus Neuron ◽

Neuron Apoptosis

Xiaoyaosan (XYS) decoction is a famous prescription for the treatment of mental disorders in China. In this experiment, we explored the way in which XYS decoction-reverse hippocampus neuron apoptosis in vitro. We used XYS decoction-containing serum to treat oxidative-stress-induced hippocampus neuron apoptosis and used immunofluorescence to determine the concentration of free calcium, mitochondrial membrane potential, and apoptotic rate of neuron. Results showed that 3-hour oxidative stress decrease mitochondrial membrane potential, increase the concentration of free calcium and apoptotic rate of neuron via triggering pathological changes of nucleus such as karyorrhexis, karyopyknosis. Low, medium, high dose of XYS-decoction-containing serum could reverse these phenomenon, and the effect of low-dose XYS-decoction-containing serum was significant in improving mitochondrial membrane potential and apoptotic rate of neuron. These findings suggest that XYS decoction may be helpful in reducing oxidative-stress-induced hippocampus neuron apoptosis.

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Anti-Apoptotic Effect of Angelica Polysaccharide (APS) on Cryopreservation of Platelets

Blood ◽

10.1182/blood-2021-151963 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 3250-3250

Author(s):

Mo Yang ◽

Weiqing Su ◽

Liuming Yang ◽

Huimin Kong ◽

Huiling Wei ◽

...

Keyword(s):

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Caspase 3 ◽

Conflicts Of Interest ◽

Annexin V ◽

Control Group ◽

Apoptotic Effect ◽

Vitro Effect

Abstract Background: Angelica Polysaccharide (APS) is from the root of Radix Angelicae Sinensis (Danggui). Danggui has been used for centuries to treat blood-deficiency related diseases. The hematopoietic effect of Danggui may be related to its constituent, polysaccharide. The effects of angelica polysaccharide on cryopreservation of platelets and megakaryocytes have not been well studied. This study focused on anti-apoptotic effect of APS and TPO on cryopreservation of platelets and megakaryocytes and provided new methods for prolonging the preservation time of platelets in vitro. Methods: The expression of platelet membrane glycoprotein CD41 and CD61, as well as the platelet apoptotic rate, Caspase 3 expression and mitochondrial membrane potential (MMP) were detected by flow cytometry; the anti-apoptotic mechanism of APS by PI3K /AKT signaling pathway was analyzed by Western blot assay. CFU assays were used to determine the effects of APS on megakaryocytic progenitor cells. Analyses of Annexin V, Caspase-3, and Mitochondrial Membrane Potential were conducted in megakaryocytic cell line M-07e. The effects of APS on cells treated with Ly294002, PI3K inhibitor and the effect of APS on the p-AKT were also studied. Results: The platelets were divided into 4 group: control group (4 ℃ stored platelets), APS group (APS-treated platelets stored at 4 ℃), LY294002 group (LY294002-treated platelets stored at 4 ℃) and LY294002+APS group (LY294002+APS treated platelets stored at 4 ℃). The apoptotic rate of platelets in LY294002 group was obviously increased. Compared with control group, the expression of CD41 and CD61 gradually decreased along with the enhancement of LY294002 concentrations (r=-0.953). The apoptotic rate of platelets in LY294002 group was enhanced significantly (P<0.05). While in LY294002+APS group, the apoptotic rate of platelets was significantly reduced (P<0.05) as compare with LY294002 group, which suggest that APS has an anti-apoptotic effect on the cryopreserved platelets. APS decreased the expression of Caspase-3 and inhibited the reduction of mitochondrial membrane potential induced by LY294002. Moreover, APS increased the activation of PI3K /AKT pathway in Platelets . We further analyzed the in vitro effect of APS on CFU-MK formation. APS (50 ug/ml) enhanced TPO (50 ng/ml) -induced CFU-MK formation (p=0.06, n=4). APS also significantly enhanced PDGF, bFGF and VEGF-induced CFU-MK formation (n=4). Moreover, the anti-apoptotic effect of APS in M-07e cells was also demonstrated by Annexin-V, Caspase-3, and JC-1 assays. Adding LY294002 alone increased the percentage of cells undergoing apoptosis. However, additional of APS to LY294002-treated cells reversed the percentage of cells undergoing apoptosis. Furthermore, addition of APS significantly increased the p-AKT. Conclusion: APS, like TPO, has an anti-apoptotic effect on the cryopreserved platelets and megakaryocytes through activating PI3K/AKT, decreasing the expression of Caspase-3 and inhibiting the reduction of MMP. Disclosures No relevant conflicts of interest to declare.

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Synthesis and Biological Evaluation of Novel Heterocyclic Imines Linked Coumarin- Thiazole Hybrids as Anticancer Agents

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520619666190207140120 ◽

2019 ◽

Vol 19 (4) ◽

pp. 557-566 ◽

Cited By ~ 7

Author(s):

Nerella S. Goud ◽

Mahammad S. Ghouse ◽

Jatoth Vishnu ◽

Jakkula Pranay ◽

Ravi Alvala ◽

...

Keyword(s):

Cell Cycle ◽

Membrane Potential ◽

Fluorescence Spectroscopy ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Annexin V ◽

Biological Evaluation ◽

Dependent Manner ◽

Dapi Staining ◽

Dose Dependent

Background: Human Galectin-1, a protein of lectin family showing affinity towards β-galactosides has emerged as a critical regulator of tumor progression and metastasis, by modulating diverse biological events including homotypic cell aggregation, migration, apoptosis, angiogenesis and immune escape. Therefore, galectin-1 inhibitors might represent novel therapeutic agents for cancer. Methods: A new series of heterocyclic imines linked coumarin-thiazole hybrids (6a-6r) was synthesized and evaluated for its cytotoxic potential against a panel of six human cancer cell lines namely, lung (A549), prostate (DU-145), breast (MCF-7 & MDA-MB-231), colon (HCT-15 & HT-29) using MTT assay. Characteristic apoptotic assays like DAPI staining, cell cycle, annexin V and Mitochondrial membrane potential studies were performed for the most active compound. Furthermore, Gal-1 inhibition was confirmed by ELISA and fluorescence spectroscopy. Results: Among all, compound 6g 3-(2-(2-(pyridin-2-ylmethylene) hydrazineyl) thiazol-4-yl)-2H-chromen-2- one exhibited promising growth inhibition against HCT-15 colorectal cancer cells with an IC50 value of 1.28 ± 0.14 µM. The characteristic apoptotic morphological features like chromatin condensation, membrane blebbing and apoptotic body formation were clearly observed with compound 6g on HCT-15 cells using DAPI staining studies. Further, annexin V-FITC/PI assay confirmed effective early apoptosis induction by treatment with compound 6g. Loss of mitochondrial membrane potential and enhanced ROS generation were confirmed with JC-1 and DCFDA staining method, respectively by treatment with compound 6g, suggesting a possible mechanism for inducing apoptosis. Moreover, flow cytometric analysis revealed that compound 6g blocked G0/G1 phase of the cell cycle in a dose-dependent manner. Compound 6g effectively reduced the levels of Gal-1 protein in a dose-dependent manner. The binding constant (Ka) of 6g with Gal-1 was calculated from the intercept value which was observed as 1.9 x 107 M-1 by Fluorescence spectroscopy. Molecular docking studies showed strong interactions of compound 6g with Gal-1 protein. Conclusion: Our studies demonstrate the anticancer potential and Gal-1 inhibition of heterocyclic imines linked coumarin-thiazole hybrids.

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Leishmanicidal Activity of Betulin Derivatives in Leishmania amazonensis; Effect on Plasma and Mitochondrial Membrane Potential, and Macrophage Nitric Oxide and Superoxide Production

Microorganisms ◽

10.3390/microorganisms9020320 ◽

2021 ◽

Vol 9 (2) ◽

pp. 320

Author(s):

Wilmer Alcazar ◽

Sami Alakurtti ◽

Maritza Padrón-Nieves ◽

Maija Liisa Tuononen ◽

Noris Rodríguez ◽

...

Keyword(s):

Nitric Oxide ◽

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Leishmania Amazonensis ◽

Superoxide Production ◽

In Vitro Susceptibility ◽

Intracellular Parasites ◽

Betulin Derivatives

Herein, we evaluated in vitro the anti-leishmanial activity of betulin derivatives in Venezuelan isolates of Leishmania amazonensis, isolated from patients with therapeutic failure. Methods: We analyzed promastigote in vitro susceptibility as well as the cytotoxicity and selectivity of the evaluated compounds. Additionally, the activity of selected compounds was determined in intracellular amastigotes. Finally, to gain hints on their potential mechanism of action, the effect of the most promising compounds on plasma and mitochondrial membrane potential, and nitric oxide and superoxide production by infected macrophages was determined. Results: From the tested 28 compounds, those numbered 18 and 22 were chosen for additional studies. Both 18 and 22 were active (GI50 ≤ 2 µM, cytotoxic CC50 > 45 µM, SI > 20) for the reference strain LTB0016 and for patient isolates. The results suggest that 18 significantly depolarized the plasma membrane potential (p < 0.05) and the mitochondrial membrane potential (p < 0.05) when compared to untreated cells. Although neither 18 nor 22 induced nitric oxide production in infected macrophages, 18 induced superoxide production in infected macrophages. Conclusion: Our results suggest that due to their efficacy and selectivity against intracellular parasites and the potential mechanisms underlying their leishmanicidal effect, the compounds 18 and 22 could be used as tools for designing new chemotherapies against leishmaniasis.

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Review of T-2307, an Investigational Agent That Causes Collapse of Fungal Mitochondrial Membrane Potential

Journal of Fungi ◽

10.3390/jof7020130 ◽

2021 ◽

Vol 7 (2) ◽

pp. 130

Author(s):

Nathan P. Wiederhold

Keyword(s):

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Candida Species ◽

Mammalian Cells ◽

Mitochondrial Membrane ◽

Fungal Infections ◽

Published Data ◽

Candida Auris

Invasive infections caused by Candida that are resistant to clinically available antifungals are of increasing concern. Increasing rates of fluconazole resistance in non-albicans Candida species have been documented in multiple countries on several continents. This situation has been further exacerbated over the last several years by Candida auris, as isolates of this emerging pathogen that are often resistant to multiple antifungals. T-2307 is an aromatic diamidine currently in development for the treatment of invasive fungal infections. This agent has been shown to selectively cause the collapse of the mitochondrial membrane potential in yeasts when compared to mammalian cells. In vitro activity has been demonstrated against Candida species, including C. albicans, C. glabrata, and C. auris strains, which are resistant to azole and echinocandin antifungals. Activity has also been reported against Cryptococcus species, and this has translated into in vivo efficacy in experimental models of invasive candidiasis and cryptococcosis. However, little is known regarding the clinical efficacy and safety of this agent, as published data from studies involving humans are not currently available.

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