Doxorubicin (DOXO)-induced cardiomyopathy (DIC) is a lethal complication in cancer patients. Major mechanisms of DIC involve oxidative stress in cardiomyocytes and hyperactivated immune response. Extracellular vesicles (EVs) mediate cell-cell communication during oxidative stress.
View Article and Find Full Text PDFWe have employed a redox-active MnP (MnTnBuOE-2-PyP, Mn(III) meso-tetrakis (N-n-butoxyethylpyridinium-2-yl) porphyrin) frequently identified as superoxide dismutase mimic or BMX-001, to explore the redox status of normal ovarian cell in relation to two ovarian cancer cell lines: OV90 human serous ovarian cancer cell and chemotherapy-resistant OV90 cell (OVCD). We identified that OVCD cells are under oxidative stress due to high hydrogen peroxide (HO) levels and low glutathione peroxidase and thioredoxin 1. Furthermore, OVCD cells have increased glycolysis activity and mitochondrial respiration when compared to immortalized ovarian cells (hTER7) and parental cancer cells (OV90).
View Article and Find Full Text PDFExtracellular vesicles (EVs) generated from redox active anticancer drugs are released into the extracellular environment. These EVs contain oxidized molecules and trigger inflammatory responses by macrophages. Using a mouse model of doxorubicin (DOX)-induced tissue injury, we previously found that the major sources of circulating EVs are from heart and liver, organs that are differentially affected by DOX.
View Article and Find Full Text PDFCardiac injury is a major cause of death in cancer survivors, and biomarkers for it are detectable only after tissue injury has occurred. Extracellular vesicles (EV) remove toxic biomolecules from tissues and can be detected in the blood. Here, we evaluate the potential of using circulating EVs as early diagnostic markers for long-term cardiac injury.
View Article and Find Full Text PDFThe short- and long-term side effects of chemotherapy limit the maximum therapeutic dose and impair quality of life of survivors. Injury to normal tissues, especially chemotherapy-induced cardiomyopathy, is an unintended outcome that presents devastating health impacts. Approximately half of the drugs approved by the Food and Drug Administration for cancer treatment are associated with the generation of reactive oxygen species, and Doxorubicin (Dox) is one of them.
View Article and Find Full Text PDFObjective: Current chemotherapy treatments available for treating high-grade brain tumors, Temozolomide (TMZ) or Bevacizumab (BEV), not only have specific anti-tumor mechanisms, but also have an effect on mitochondria. However, effects of both drugs on mitochondria isolated from human brain tumors have not been thoroughly investigated. This study determined the direct effects of TMZ and BEV as well as the neurotoxic condition (calcium overload), on the function of mitochondria and compared these effects on mitochondria isolated from low- and high-grade human brain tumors.
View Article and Find Full Text PDFIt has been demonstrated that cancer cells are under high levels of oxidative stress and express high levels of Manganese superoxide dismutase (MnSOD) to protect themselves and support the anabolic metabolism needed for growth and cell motility. The aim of this study was to identify proteins that may have a correlation with invasion and redox regulation by mitochondrial reactive oxygen species (ROS). MnSOD scavenges superoxide anions generated from mitochondria and is an important regulator of cellular redox status.
View Article and Find Full Text PDFBackground And Aims: Cardiac mitochondrial Ca(2+) overload plays a critical role in mechanical and electrical dysfunction leading to cardiac cell death and fatal arrhythmia. Because Ca(2+) overload is related to mitochondrial permeability transition, reactive oxygen species (ROS) production and membrane potential (ΔΨm) dissipation, we probed the mechanistic association between Ca(2+) overload, oxidative stress, mitochondrial permeability transition pore (mPTP) and mitochondrial calcium uniporter (MCU) in isolated cardiac mitochondria.
Methods: Various concentrations of Ca(2+) (5-200 μM) were used to induce mitochondrial dysfunction.
Aims: Since variety in response to Ca(2+)-induced mitochondrial dysfunction in different neuronal mitochondrial populations is associated with the pathogenesis of several neurological diseases, we investigated the effects of Ca(2+) overload on synaptic (SM) and nonsynaptic mitochondrial (NM) dysfunction and probed the effects of cyclosporin A (CsA), 4'-chlorodiazepam (CDP) and Ru360 on relieving mitochondrial damage.
Main Methods: SM and NM mitochondria were isolated from rats' brains (n=5/group) and treated with various concentrations (5, 10, 100, and 200 μM) of Ca(2+), with and without CsA (mPTP blocker), CDP (PBR/TSPO blocker) and Ru360 (MCU blocker) pretreatments. Mitochondrial function was determined by mitochondrial swelling, ROS production and mitochondrial membrane potential changes (ΔΨm).