scholarly journals Toxins in Botanical Dietary Supplements: Blue Cohosh Components Disrupt Cellular Respiration and Mitochondrial Membrane Potential

2013 ◽  
Vol 77 (1) ◽  
pp. 111-117 ◽  
Author(s):  
Sandipan Datta ◽  
Fakhri Mahdi ◽  
Zulfiqar Ali ◽  
Mika B. Jekabsons ◽  
Ikhlas A. Khan ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Dietary Supplements ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Cellular Respiration ◽  
Botanical Dietary Supplements

scholarly journals Depletion of cardiolipin induces major changes in energy metabolism in Trypanosoma brucei bloodstream forms

2020 ◽  
Author(s):  
Mauro Serricchio ◽  
Carolina Hierro-Yap ◽  
David Schädeli ◽  
Hisham Ben Hamidane ◽  
Andrew Hemphill ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Trypanosoma Brucei ◽  
Mitochondrial Membrane Potential ◽  
Atp Synthase ◽  
Mitochondrial Membrane ◽  
Alternative Oxidase ◽  
Mitochondrial Proteins ◽  
Cellular Respiration ◽  
Atp Levels ◽  
Glycerol 3 Phosphate Dehydrogenase

AbstractCardiolipin (CL) is a mitochondrial inner membrane glycerophospholipid that associates with mitochondrial proteins to promote their activities and to facilitate protein complex and super-complex formation. Loss of CL leads to destabilized respiratory complexes and mitochondrial dysfunction. The role of CL in an organism lacking a conventional electron transport chain (ETC) has not been elucidated so far. We now report that in Trypanosoma brucei bloodstream forms, in which the ETC is truncated and composed of alternative oxidase and glycerol-3-phosphate dehydrogenase, and the mitochondrial membrane potential is generated by the hydrolytic action of the FoF1-ATP synthase, the inducible depletion of cardiolipin synthase (TbCls) is essential for parasite survival. Loss of TbCls and CL caused a rapid drop in ATP levels and a decline in the mitochondrial membrane potential. Unbiased proteomic analyses revealed a reduction in the levels of many mitochondrial proteins, most notably of FoF1-ATP synthase subunits and of the alternative oxidase, resulting in a strong decline of glycerol-3-phosphate-stimulated oxygen consumption. Interestingly, the changes in cellular respiration preceded the observed decrease in FoF1-ATPase stability, suggesting that the truncated ETC is the first pathway responding to the decline in CL. In addition, proteomic and metabolomic analyses revealed that select proteins and pathways involved in glucose and amino acid transport and metabolism are up-regulated during CL depletion, possibly as a stress response to restore cellular ATP levels.

scholarly journals Maintenance of Respiration Capacity Is an Early Predictor of Drug Resistance in Cancer Cells

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 2157-2157
Author(s):  
Cornelia A Brendel ◽  
Katharina Henkenius ◽  
Melanie Maerken ◽  
Tom Kaiser ◽  
Larissa Greif ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Membrane Potential ◽  
Cancer Therapy ◽  
Cancer Cells ◽  
Mitochondrial Membrane Potential ◽  
Mtt Assay ◽  
Mitochondrial Function ◽  
Mitochondrial Membrane ◽  
Drug Exposure ◽  
Cellular Respiration

Abstract Inherent or acquired drug resistance is the major obstacle in cancer therapy. An individual prediction of response to cancer therapy would be highly appreciated. It has been reported that the mitochondrial function of cancer cells correlates with the treatment response in different cancer entities (Chonghaile et al., Science 2011 and Vo et al., Cell 2012). However, as the method of BCL-2 peptide priming measurement (“BH3 profiling”) seemed to be rather complicated and error-prone in our hand we sought to determine mitochondrial function by analyzing cellular respiration. We established three different drug resistant human cancer cell lines (MV4-11, HL-60 and NCl-H82) by continuous exposure to Sorafenib, Cytarabine (Ara-C) or Etoposid (VP-16) respectively. Cellular respiration was measured as oxygen consumption rate (OCR) 24h after drug exposure employing the XF96 extracellular Flux Analyzer. Viability, reduction equivalents NADH/NADPH and mitochondrial membrane potential of the cells were concomitantly determined by flow cytometry via 4’, 6-diamidino-2-phenylindole (DAPI) exclusion, (4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Tetramethylrhodamine ethyl ester (TMRE) staining with flow cytometric analysis, respectively. All resistant cancer cells maintained their respiration capacity upon exposure to tyrosine kinase inhibitors, chemotherapeutics or topoisomerase inhibitors, whereas the respiration of drug sensitive cancer cells decreased significantly. Moreover, resistant MV4-11 and HL-60 cells exhibited a metabolic shift towards glycolysis after drug treatment. In contrast sensitive cancer cells showed a decline in respiration and glycolysis in a dose dependent manner. Decrease of respiration was evident at 24h post treatment, while the onset of apoptosis was measurable 48-120h later. Reduction equivalents NADH/NADPH but not mitochondrial membrane potential were diminished in sensitive cells after 24h drug exposure, but dose dependency was more distinct with OCR analysis. The increase of glycolysis in resistant cell lines was also not detectable with the MTT assay. Our data indicate cellular metabolism and in particular respiration as an early, sensitive and reliable surrogate parameter of drug sensitivity in viable cells that might therefore be applicable in order to determine drug responsiveness in primary cancer cells in a prospective manner. Disclosures No relevant conflicts of interest to declare.

Platelets apoptosis in rats after global brain ischemia

2018 ◽  
pp. 27-35
Author(s):  
А.А. Соколовская ◽  
Э.Д. Вирюс ◽  
В.В. Александрин ◽  
А.С. Роткина ◽  
К.А. Никифорова ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Ischemic Stroke ◽  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Brain Ischemia ◽  
Mitochondrial Membrane ◽  
Male Rats ◽  
Global Brain Ischemia ◽  
Platelet Apoptosis ◽  
Global Brain

Цель исследования. Ишемические повреждения головного мозга, являются одной из наиболее частой причин инвалидности и смертности во всем мире. Недавно была установлена роль апоптоза тромбоцитов в патофизиологии инсульта, однако его механизмы до сих пор остаются невыясненными. Несмотря на различные экспериментальные модели, направленные на мониторинг апоптоза тромбоцитов, результаты, относительно изучения и выявления апоптоза тромбоцитов при ишемии головного мозга у крыс, весьма немногочисленны. Цель исследования - анализ апоптоза тромбоцитов с помощью метода проточной цитофлуориметрии на модели глобальной ишемии мозга у крыс. Методика. В экспериментах использовано 6 крыс-самцов Вистар в возрасте от 5 до 6 мес., разделенных на 2 группы: интактный контроль (К) и глобальная ишемия головного мозга. Модель глобальной ишемии головного мозга у крыс воспроизводилась путём билатеральной окклюзии общих сонных артерий на фоне гипотензии. Уровень системного артериального давления снижали посредством кровопотери до 40-45 мм рт. ст. Суспензию тромбоцитов крыс получали методом гельфильтрации с использованием сефарозы 2B. Для анализа экстернализации фосфатидилсерина (ФС) тромбоциты крыс инкубировали с Аннексином V-PE в связывающем буфере. Для оценки митохондриального мембранного потенциала (ММП) тромбоциты инкубировали с катионным красителем JC-1. После инкубации образцы немедленно анализировали на проточном цитофлуориметре FACSCalibur (Becton Dickinson, США). Результаты. Согласно полученным данным, экстернализация ФС на тромбоцитах крыс, перенесших инсульт, была значительно выше (53,45 ± 4,21%), чем в контрольной группе крыс (5,27 ± 2,40%). Данный эффект подтверждается выраженной деполяризацией митохондриальных мембран (DYm). После экспериментальной ишемии мозга почти 40% тромбоцитов было деполяризовано. Заключение. Использованный в работе подбор методов и маркеров обеспечивает понимание механизмов апоптоза тромбоцитов как в экспериментальных, так и в клинических условиях. Полученные данные позволяют сделать заключение, что апоптоз тромбоцитов является одним из факторов развития глобальной ишемии головного мозга у крыс. Результаты могут быть использованы для понимания механизмов, участвующих в развитии ишемического повреждения, что, в свою очередь, может быть использовано при разработке новых терапевтических стратегий. Aim. Stroke is one of the most common causes of disability and mortality worldwide. Multiple experimental models of stroke have focused on monitoring of platelet apoptosis. However, studies on and detection of platelet apoptosis in rats with ischemic stroke are very scarce. We investigated platelet apoptosis in rats with global brain ischemia using flow cytometry. Methods. Experiments were carried out on healthy, adult Wistar male rats weighing 300-350 g. The rats were divided into the following 2 groups: intact rats and rats with global brain ischemia. Global brain ischemia was induced by two-vessel (2-VO) carotid occlusion in combination with hypotension. Systemic blood pressure was reduced by 40-45 mm Hg by inducing haemorrhage. Platelets were isolated by gel filtration on Sepharose 2B. For evaluation of phosphatidylserine (PS) externalization, platelets were incubated with Annexin V-PE and analyzed on FACSCalibur (BD Biosciences). Mitochondrial membrane potential (DY) was measured during platelets apoptosis using JC-1, a mitochondrial membrane potential indicator. Platelets were analyzed by flow cytometry immediately after the incubation. Results. PS externalization on platelets was significantly greater after global brain ischemia (53.45 ± 4.21%) than in the control group (5.27 ± 2.40%). Pronounced depolarization of mitochondrial membrane potential (DYm) confirmed this finding. In the rat group with experimental brain ischemia, almost 40% (35.24 ± 5.21%) of platelets were depolarized. Conclusion. Our results provide insight into mechanisms involved in platelet apoptosis during ischemic stroke and can be used in further development of new therapeutic strategies.

Reserpine Induces Apoptosis and Cell Cycle Arrest in Hormone Independent Prostate Cancer Cells through Mitochondrial Membrane Potential Failure

2019 ◽  
Vol 18 (9) ◽  
pp. 1313-1322 ◽  
Author(s):  
Manjula Devi Ramamoorthy ◽  
Ashok Kumar ◽  
Mahesh Ayyavu ◽  
Kannan Narayanan Dhiraviam
Keyword(s):  
Prostate Cancer ◽  
Reactive Oxygen Species ◽  
Cell Cycle ◽  
Membrane Potential ◽  
Cancer Cells ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Prostate Cancer Cells

Background: Reserpine, an indole alkaloid commonly used for hypertension, is found in the roots of Rauwolfia serpentina. Although the root extract has been used for the treatment of cancer, the molecular mechanism of its anti-cancer activity on hormonal independent prostate cancer remains elusive. Methods: we evaluated the cytotoxicity of reserpine and other indole alkaloids, yohimbine and ajmaline on Prostate Cancer cells (PC3) using MTT assay. We investigated the mechanism of apoptosis using a combination of techniques including acridine orange/ethidium bromide staining, high content imaging of Annexin V-FITC staining, flow cytometric quantification of the mitochondrial membrane potential and Reactive Oxygen Species (ROS) and cell cycle analysis. Results: Our results indicate that reserpine inhibits DNA synthesis by arresting the cells at the G2 phase and showed all standard sequential features of apoptosis including, destabilization of mitochondrial membrane potential, reduced production of reactive oxygen species and DNA ladder formation. Our in silico analysis further confirmed that indeed reserpine docks to the catalytic cleft of anti-apoptotic proteins substantiating our results. Conclusion: Collectively, our findings suggest that reserpine can be a novel therapeutic agent for the treatment of androgen-independent prostate cancer.

Sign in / Sign up

Export Citation Format

Share Document