Malignant Cells in the Marrow and Blood of Patients with Hematopoietic Malignancies Have Higher Mitochondrial Membrane Potential as Measured with the Potentiometric Dye JC-1.

Abstract Background: Immunophenotyping is an important method to define hematopoietic malignancies, but used alone, its ability to provide functional information about the malignant cells is limited. JC-1 is a fluorescent dye used to measure mitochondrial membrane potential in cells. We have developed a flow cytometric assay using JC-1 in conjunction with standard cell surface markers to characterize clinical samples from patients with hematologic malignancies. Methods: Ficoll-purified cells derived from the blood or marrow were stained with JC-1, and analyzed at 530 nm and 590nm to assess mitochondrial mass and mitochondrial membrane potential, respectively. Malignant and normal cell populations were assigned and gated by analysis of forward scatter and side scatter. Gating in this manner identified energetically discrete cell populations confirmed by back gating analysis. Results: To date we have measured the mitochondrial membrane potential from the bone marrow or peripheral blood of 3 normal individuals and 22 patients with acute and chronic leukemias and lymphoma involving the marrow. Samples have been analyzed from AML (6), ALL (3), CML- chronic phase (2), CLL (5), mantle cell lymphoma (3), diffuse large B-cell lymphoma (1) and acute biphenotypic leukemia (2). Compared with samples derived from normal individuals, malignant cells have a different energetic signature, and in nearly all instances, a substantially higher mitochondrial membrane potential. The mitochondrial membrane potential of malignant cells was 5.5 times higher (range 2.15–12) than normal cells within the same samples in 19 of 20 specimens (given the overlap in cell populations, CML samples were excluded and 1 CLL sample had a mitochondrial membrane potential that was the same as the normal population). Mitochondrial membrane potential is also higher in malignant cells compared with peripheral blood and marrow cells from normal individuals. While cells derived from patients with acute leukemias appear to be energetically homogeneous, cells from both patients with CML and 4 of 5 patients with CLL had at least 2 energetically discrete subpopulations despite being cytogenetically homogeneous (in the case of the CML samples) or immunophenotypically homogenous (in the case of the CLL samples). Conclusions: JC-1 staining can be performed reliably in concert with immunocytochemistry and provides insight into the metabolism of malignant hematopoietic cells. Preliminary data indicate that malignant cells from patients with leukemia and lymphoma have a high mitochondrial membrane potential which may reflect altered oxidative metabolism. This may serve as a metabolic signature for monitoring minimal residual disease or assessing the effect of therapeutic agents on functional status of malignant populations.

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Alpha-Tocotrienol Prevents Oxidative Stress-Mediated Post-Translational Cleavage of Bcl-xL in Primary Hippocampal Neurons

International Journal of Molecular Sciences ◽

10.3390/ijms21010220 ◽

2019 ◽

Vol 21 (1) ◽

pp. 220 ◽

Cited By ~ 4

Author(s):

Han-A Park ◽

Nelli Mnatsakanyan ◽

Katheryn Broman ◽

Abigail U. Davis ◽

Jordan May ◽

...

Keyword(s):

Membrane Potential ◽

Mitochondrial Dysfunction ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Function ◽

Hippocampal Neurons ◽

Mitochondrial Membrane ◽

Antioxidant Properties ◽

B Cell Lymphoma ◽

Atp Depletion ◽

Primary Hippocampal Neurons

B-cell lymphoma-extra large (Bcl-xL) is an anti-apoptotic member of the Bcl2 family of proteins, which supports neurite outgrowth and neurotransmission by improving mitochondrial function. During excitotoxic stimulation, however, Bcl-xL undergoes post-translational cleavage to ∆N-Bcl-xL, and accumulation of ∆N-Bcl-xL causes mitochondrial dysfunction and neuronal death. In this study, we hypothesized that the generation of reactive oxygen species (ROS) during excitotoxicity leads to formation of ∆N-Bcl-xL. We further proposed that the application of an antioxidant with neuroprotective properties such as α-tocotrienol (TCT) will prevent ∆N-Bcl-xL-induced mitochondrial dysfunction via its antioxidant properties. Primary hippocampal neurons were treated with α-TCT, glutamate, or a combination of both. Glutamate challenge significantly increased cytosolic and mitochondrial ROS and ∆N-Bcl-xL levels. ∆N-Bcl-xL accumulation was accompanied by intracellular ATP depletion, loss of mitochondrial membrane potential, and cell death. α-TCT prevented loss of mitochondrial membrane potential in hippocampal neurons overexpressing ∆N-Bcl-xL, suggesting that ∆N-Bcl-xL caused the loss of mitochondrial function under excitotoxic conditions. Our data suggest that production of ROS is an important cause of ∆N-Bcl-xL formation and that preventing ROS production may be an effective strategy to prevent ∆N-Bcl-xL-mediated mitochondrial dysfunction and thus promote neuronal survival.

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Alterations in mitochondrial membrane potential in peripheral blood mononuclear cells in Parkinson’s Disease: Potential for a novel biomarker

Restorative Neurology and Neuroscience ◽

10.3233/rnn-180852 ◽

2018 ◽

Vol 36 (6) ◽

pp. 719-727 ◽

Cited By ~ 2

Author(s):

Rizwana Qadri ◽

Manju Namdeo ◽

Madhuri Behari ◽

Vinay Goyal ◽

Subhadra Sharma ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Peripheral Blood Mononuclear Cells ◽

Peripheral Blood ◽

Mitochondrial Membrane ◽

Mononuclear Cells ◽

Peripheral Blood Mononuclear ◽

Blood Mononuclear Cells

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Mitochondrial Membrane Potential and Apoptosis Peripheral Blood Monocytes in Severe Human Sepsis

American Journal of Respiratory and Critical Care Medicine ◽

10.1164/ajrccm.164.3.2009088 ◽

2001 ◽

Vol 164 (3) ◽

pp. 389-395 ◽

Cited By ~ 127

Author(s):

CHRISTOPHE ADRIE ◽

MARIA BACHELET ◽

MURIEL VAYSSIER-TAUSSAT ◽

FRANÇOISE RUSSO-MARIE ◽

ISABELLE BOUCHAERT ◽

...

Keyword(s):

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Peripheral Blood ◽

Mitochondrial Membrane ◽

Blood Monocytes ◽

Peripheral Blood Monocytes ◽

Human Sepsis

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Stable Differences in Intrinsic Mitochondrial Membrane Potential of Tumor Cell Subpopulations Reflect Phenotypic Heterogeneity

International Journal of Cell Biology ◽

10.1155/2011/978583 ◽

2011 ◽

Vol 2011 ◽

pp. 1-11 ◽

Cited By ~ 24

Author(s):

Michele A. Houston ◽

Leonard H. Augenlicht ◽

Barbara G. Heerdt

Keyword(s):

Membrane Potential ◽

Tumor Cell ◽

Disease Progression ◽

Mitochondrial Membrane Potential ◽

Mammary Tumor ◽

Mitochondrial Membrane ◽

Cell Populations ◽

Mammary Tumor Cell ◽

Colonic Tumor ◽

Primary Mammary Tumor

Heterogeneity among cells that constitute a solid tumor is important in determining disease progression. Our previous work established that, within a population of metastatic colonic tumor cells, there are minor subpopulations of cells with stable differences in their intrinsic mitochondrial membrane potential (ΔΨm), and that these differences in ΔΨm are linked to tumorigenic phenotype. Here we expanded this work to investigate primary mammary, as well as colonic, tumor cell lines. We show that within a primary mammary tumor cell population, and in both primary and metastatic colonic tumor cell populations, there are subpopulations of cells with significant stable variations in intrinsic ΔΨm. In each of these 3 tumor cell populations, cells with relatively higher intrinsic ΔΨm exhibit phenotypic properties consistent with promotion of tumor cell survival and expansion. However, additional properties associated with invasive potential appear in cells with higher intrinsic ΔΨm only from the metastatic colonic tumor cell line. Thus, it is likely that differences in the intrinsic ΔΨm among cells that constitute primary mammary tumor populations, as well as primary and metastatic colonic tumor populations, are markers of an acquired tumor phenotype which, within the context of the tumor, influence the probability that particular cells will contribute to disease progression.

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