Fluctuating vs. continuous exposure to H₂O₂: the effects on mitochondrial membrane potential, intracellular calcium, and NF-κB in astroglia.
Using sorting protocol based on a simple staining method for mitochondrial membrane potential we were able to isolate subclones from an established monoclonal antibody production cell line with significantly altered physiological properties. The subclone sorted for lower mitochondrial membrane potential had a faster growth rate, attained higher final cell concentrations in batch cultures, had lower glucose and glutamine uptake and lactate production rates as well as a higher specific production rate. The subclone sorted for high mitochondrial membrane potential on the other hand had a lower growth rate and final cell count, increased glucose and glutamine consumption and lactate production rates. These subclones can now be used for genomic or proteomic analysis of properties that characterise a cell line with efficient or inefficient metabolism. In addition, the method described is a valuable tool for cell line development and optimisation, offering the possibility to isolate subclones with both ...
Purified JC-1 Mitochondrial Membrane Potential Assay Kit from Creative Biomart. JC-1 Mitochondrial Membrane Potential Assay Kit can be used for research.
NsPEF induce plasma membrane poration at lower electric fields than that required for loss of the mitochondria membrane potential (ΔΨm), indicating that nsPEFs affect plasma membranes more readily that intracellular membranes or organelles. High frequency components of nsPEFs (frequency in Hz=1/time in sec) are most effective to dissipate the mitochondria membrane potential (ΔΨm), but are less important for plasma membrane permeabilization using Ca2+ influx as a marker. Thus, the pulse waveform appears to selectively affect ΔΨm and possibly other intracellular components. Cell death is closely correlated with loss of ΔΨm; high intracellular Ca2+ is necessary, but not sufficient for cell death. Thus, nsPEF-induced cell death requires both influx of extracellular Ca2+ and dissipation of ΔΨm [20,21]. This is consistent with a "two hit" hypothesis for cell death [23,24]. At electric fields sufficient to induce cell death in 40-60% of cells, dissipation of ΔΨm is calcium-dependent. At ...
JC-10 Mitochondrial Membrane Potential Assay Kit (Flow Cytometry) (ab112133) has been cited in 2 publications. References for Rat in Flow Cyt
MitoPedia ,abbr=mtMP, Δψ [V] ,description=The mitochondrial membrane potential, mtMP, is the electric part of the protonmotive [[force]], Δp,sub>H+,/sub>. Δψ = Δp,sub>H+,/sub> - Δµ,sub>H+,/sub> / F mtMP or Δψ is the potential difference across the inner mitochondrial (mt) membrane, expressed in the electric unit of volt [V]. Electric force of the mitochondrial membrane potential is the electric energy change per motive electron or per electron moved across the transmembrane potential difference, with the number of motive electrons expressed in the unit coulomb [C]. ,info=[[Mitchell 1961 Nature]], [[Gnaiger 2014 Preface MiP2014]] }} Communicated by [[Gnaiger E]] 2012-10-05, edited 2016-02-06, 2017-09-05. :::: The chemical part of the protonmotive force, µ,sub>H+,/sub> / F stems from the difference of pH across the mt-membrane. It contains a factor that bridges the gap between the electric force [J/C] and the chemical force [J/mol]. This ...
BioAssay record AID 720637 submitted by 824: qHTS assay for small molecule disruptors of the mitochondrial membrane potential: Summary.
The amyloid beta (A beta) toxic fibrils is thought to play a central role in the onset and progression of Alzheimers disease (AD) because of it is a main formation of senile plaques. Diabetic patients are more vulnerable to caught Alzheimers disease. Vildagliptine, a novel anti diabetic agent, has been reported to exert protective effects on AD rat models in restricted study. We aimed to investigate any protective effects of vildagliptine against A beta fibrils on SH-SY5Y cell line. Vildagliptine decreased PSEN1 and PSEN2 mRNA levels which enroll A beta production. In addition, vildagliptin was downregulated caspase-3 and caspase-9 expression levels which were evoked by A beta. Also we confirmed cellular viability with real time cell analyzer and MTT assay. Our data exposed that vildagliptine has lowering effect on GSK3 beta and Tau phosphorylation. However we did not get protective effect of vildagliptine against A toxicity on mitochondrial membrane potential. These results indicate that ...
MitoMark Red I is a red fluorescent mitochondrial stain. Fluorescence intensity is dependent on mitochondrial membrane potential. Excitation/emission maxima λ ~ 578/599 nm. - Mechanism of Action & Protocol.
What is the relationship between cardiac mitochondrial metabolism and the mitochondrial membrane potential? Listen as Associate Editor Gary Lopaschuk interviews lead author Matthew Sulkin (Washington University), and expert Elaine Wan (Columbia University) about the innovative work by Sulkin and colleagues combining two different optical mapping techniques. What did the authors discover when they looked directly at the mitochondrial membrane potential during ischemia-reperfusion, and how might this inform potential therapies for ventricular arrhythmias? Listen and learn more…. ...
What is the relationship between cardiac mitochondrial metabolism and the mitochondrial membrane potential? Listen as Associate Editor Gary Lopaschuk interviews lead author Matthew Sulkin (Washington University), and expert Elaine Wan (Columbia University) about the innovative work by Sulkin and colleagues combining two different optical mapping techniques. What did the authors discover when they looked directly at the mitochondrial membrane potential during ischemia-reperfusion, and how might this inform potential therapies for ventricular arrhythmias? Listen and learn more…. ...
This web site uses cookies to optimize the user experience. You can get more information about cookie policy or know how to change the settings in our cookie policy. If you continue browsing, we assume that you accept its use.PRIVACY POLICIES - LEGAL NOTICE ...
Oxygen, Cells, Autophagy, Cell, Apoptosis, Inhibition, Treatment, Reactive Oxygen Species, Death, Growth, Cell Death, Kinase, Human, Superoxide, Role, Membrane, Membrane Potential, Mitochondrial Membrane, Mitochondrial Membrane Potential, Time
PINK1 is specifically activated by inducers of mitochondrial membrane depolarization. (a) Table of agonists tested. (b) PINK1 phosphorylation of Parkin at Ser65
TY - JOUR. T1 - Formosanin C-induced apoptosis requires activation of caspase-2 and change of mitochondrial membrane potential. AU - Lee, Jenq Chang. AU - Su, Chun Li. AU - Chen, Lin Lin. AU - Won, Shen Jeu. PY - 2009/4/30. Y1 - 2009/4/30. N2 - Formosanin C is a pure compound isolated from Paris formosana Hayata (Liliaceae). The antitumor efficacy of formosanin C has been observed in cultured cells and animal systems. However, the molecular mechanisms of formosanin C remain unknown. The results of the present study indicate that formosanin C induced apoptosis of HT-29 cells characterized by exposure of phosphatidylserine, accumulation of cells at the sub-G1 phase, fragmentation of DNA, and change of nuclear morphology in a time- and dose-related manner. The apoptotic signaling cascades may proceed via proteolytic activation of caspase-2, change of mitochondrial membrane potential (Δεm), release of cytochrome c and second mitochondria-derived activator of caspase/direct IAP binding protein with ...
The mitochondrial membrane potential, mtMP, is the electric part of the protonmotive force, ΔpH+. Δψ = ΔpH+ - ΔµH+ / F mtMP or Δψ is the potential difference across the inner mitochondrial (mt) membrane, expressed in the electric unit of volt [V]. Electric force of the mitochondrial membrane potential is the electric energy change per motive electron or per electron moved across the transmembrane potential difference, with the number of motive electrons expressed in the unit coulomb [C]. The chemical part of the protonmotive force, µH+ / F stems from the difference of pH across the mt-membrane. It contains a factor that bridges the gap between the electric force [J/C] and the chemical force [J/mol]. This factor is the Faraday constant, F, for conversion between electric force expressed in joules per coulomb or Volt [V=J/C] and chemical force with the unit joules per mole or Jol [Jol=J/mol], F = 96.4853 kJol/V = 96,485.3 C/mol Abbreviation: mtMP, Δψ [V] Reference: Mitchell 1961 ...
TY - JOUR. T1 - Exogenous adenosine Reduces the mitochondrial membrane potential of murine oocytes during the latter half of in vitro maturation and pronuclear formation following chemical activation. AU - Fujii, Wataru. AU - Funahashi, Hiroaki. PY - 2009/5/13. Y1 - 2009/5/13. N2 - The present study was undertaken to determine the effect of nucleosides on nuclear and cytoplasmic maturation of mouse oocytes. Oocyte-cumulus complexes (OCCs) were collected from large antral follicles 4 h after eCG-hCG treatment and cultured in maturation medium with or without nucleosides (4 ribo- and 4 deoxyribonucleosides) for 12 h. A majority of the oocytes examined developed to the metaphase-II stage, and the same result was found with in-vivo matured oocytes. However, mitochondrial membrane potential (MMP) was significantly lower in the oocytes matured in the presence of nucleosides than in the nucleoside-free controls. Oocyte MMP increased in vivo between 8 to 12 h after hCG injection, whereas no increases in ...
Purified Mitochondrial Membrane Potential Assay Kit (Orange Fluorescence) from Creative Biomart. Mitochondrial Membrane Potential Assay Kit (Orange Fluorescence) can be used for research.
PAN Czytelnia Czasopism, Motility, mitochondrial membrane potential and ATP content of rabbit spermatozoa stored in extender supplemented with GnRH analogue [des-Gly10, D-Ala6]-LH-RH ethylamide - Polish Journal of Veterinary Sciences
Diabetes is closely associated with increased oxidative stress, especially originating from the mitochondria. A mechanism to reduce increased mitochondria superoxide production is to reduce the mitochondria membrane potential by releasing protons across the mitochondria membrane. This phenomenon is referred to as mitochondria uncoupling since oxygen is consumed independently of ATP being produced and can be mediated by Uncoupling Proteins (UCPs). However, increased oxygen consumption is potentially detrimental for the kidney since it can cause tissue hypoxia. Therefore, this thesis aimed to investigate the role of mitochondria uncoupling for development of diabetic nephropathy.. UCP-2 was demonstrated to be the only isoform expressed in the kidney, and localized to tubular segments performing the majority of tubular electrolyte transport. Streptozotocin-induced diabetes in rats increased UCP-2 protein expression and correlated to increased non-transport dependent oxygen consumption in isolated ...
Questo indirizzo email è protetto dagli spambots. È necessario abilitare JavaScript per vederlo.. BACKGROUND. Emy Basso graduated from the University of Padova with a B.S. Degree in Biology in 1994. From the same University she earned a M.S. Degree in Biochemistry and Clinical Chemistry, in 1998. She then went to the Vollum Institute at the Oregon Health & Sciences University for three years of postgraduate research in Molecular Biology. From 2001 until 2011 she worked as staff scientist at the University of Padova. She joined the CNR in December 2011 with a researcher position.. Research summary. Over the years Ive been involved in studying mitochondrial physiology, and specifically the occurrence of a sudden increase in permeability of the mitochondrial inner membrane known as permeability transition (PT), which participates in the mechanisms of cell death through the loss of mitochondria membrane potential and the release of proapoptotic molecules. I was involved in the production of a ...
Since the discovery of the mitochondrial cristae in the mid-20th century (Palade, 1953), imaging these structures in real time has remained a formidable challenge. Because of the necessity of freezing or fixing samples before imaging, EM is incompatible with probing cristae in living cells. Conversely, whereas conventional optical microscopy has permitted live-cell imaging of mitochondria, the Abbe diffraction limit has wholly obscured the intricacies of the IMM. Recent advancements in high- and super-resolution imaging technologies, however, have enabled the visualization of cristae in living cells, leading to an appreciation that cristae are not static structures but appear to possess their own dynamics comparable with the fusion and fission that regulate the plasticity of the larger mitochondrial network (Huang X et al, 2018; Stephan et al, 2019; Giacomello et al, 2020; Kondadi et al, 2020). Furthermore, we recently showed that cristae are functionally independent bioenergetic compartments, ...
Image Analyst MKII back-calculates mitochondrial and plasma membrane potentials in millivolts that drive changes in the fluorescence intensities.
Treatment of cells with a proteosome inhibitor stabilizes a 52-kD PINK1 fragment (Lin and Kang, 2008; Zhou et al., 2008), suggesting that proteosome-independent proteolysis yields a 52-kD form of PINK1 that is subsequently degraded by the proteosome (Narendra et al., 2010). When we treated PARL KO MEFs transiently overexpressing PINK1-V5/His with MG132, the 52-kD fragment of PINK1 (Fig. 1 c, red arrowhead) was absent, and a 60-kD predicted ΔMTS-PINK1 (Fig. 1 c, orange arrowhead) was stabilized, suggesting that PARL-mediated proteolysis normally generates the 52-kD fragment. Rhomboid proteases such as PARL cleave proteins in and around membrane-spanning domains (Urban et al., 2001; Sík et al., 2004; Strisovsky et al., 2009). PARL-mediated cleavage of PINK1 in the predicted membrane-spanning domain between residues 94 and 110 would yield a protein fragment of 52 kD, which is consistent with the molecular mass of the fragment stabilized by MG132 and absent in the PARL KO MEFs.. To further analyze ...
Cell surface blebbing is an early consequence of hypoxic and toxic injury to cells. A rise in cytosolic free Ca2+ has been suggested as the stimulus for bleb formation and the final common pathway to irreversible cell injury. Here, using digitized low-light video microscopy, we examine blebbing, c …
Methods The model of hypoxia/reoxygenation (H/R) injury was established through hypoxia for 6 h and reoxygenation for 4 h in cardiomyocytes of H9c2, We measured the survival rate by Typan blue exclusion, apoptosis rate of cardiomyocytes by FACS analysis, and mitochondrial membrane potential by JC-1 fluorescent probe. All measurement data were expressed as mean±SD of mean, and statistically analysed using one-way ANOVA analysis and Dunnett test. Differences were considered significant when P was,0.05.. ...
NIR Mitochondrial Membrane Potential Assay Kit (Flow Cytometry) (ab112149). MOMP detection in FL4 channel. Ex/Em: 635/660 nm. Ideal for multi-parameter studies.
TCL1A Enhances the phosphorylation and activation of AKT1, AKT2 and AKT3. Promotes nuclear translocation of AKT1. Enhances cell proliferation, stabilizes mitochondrial membrane potential and promotes cell survival. Homodimer. Interacts with AKT1, AKT2 and AKT3 (via PH domain). Interacts with PNPT1; the interaction has no effect on PNPT1 exonuclease activity. Restricted in the T-cell lineage to immature thymocytes and activated peripheral lymphocytes. Preferentially expressed early in T- and B-lymphocyte differentiation. Belongs to the TCL1 family. Note: This description may include information from UniProtKB ...
Congrats to How - he successfully completed his master studies with the analysis of mitochondrial membrane potentials in the Bergami Lab. He disappeared for hours to get live cell imaging running and put a lot efforts in the analysis of the obtained signals. Unfortunately there are rumors that he might leave us to start his…
Video created by 杜克大学 for the course 人体生理学导论. We hope you are enjoying the course! Last weeks lectures can be challenging because we introduce many concepts that may be new to you. This module will allow you to apply some of the concepts that ...
Video created by Университет Дьюка for the course Введение в физиологию человека. We hope you are enjoying the course! Last weeks lectures can be challenging because we introduce many concepts that may be new to you. This module will allow you ...
The lipophilic cation JC‐1 (5,5′,6,6′‐tetrachloro‐1,1′,3,3′‐tetraethyl‐benzimidazolyl carbocyanine iodide) has been used for more than 20 years as a specific dye for measuring mitochondrial membrane potential (ΔΨm)
Diabetes is closely associated with increased oxidative stress, especially originating from the mitochondria. A mechanism to reduce increased mitochondria superoxide production is to reduce the mitochondria membrane potential by releasing protons across the mitochondria membrane. This phenomenon is referred to as mitochondria uncoupling since oxygen is consumed independently of ATP being produced and can be mediated by Uncoupling Proteins (UCPs). However, increased oxygen consumption is potentially detrimental for the kidney since it can cause tissue hypoxia. Therefore, this thesis aimed to investigate the role of mitochondria uncoupling for development of diabetic nephropathy.. UCP-2 was demonstrated to be the only isoform expressed in the kidney, and localized to tubular segments performing the majority of tubular electrolyte transport. Streptozotocin-induced diabetes in rats increased UCP-2 protein expression and correlated to increased non-transport dependent oxygen consumption in isolated ...
Effect of arsenic, amla and their co-treatment on mitochondrial membrane potential of thymocytes of mice. Cells were incubated with Rh 123 and fluorescence was
Close The Infona portal uses cookies, i.e. strings of text saved by a browser on the users device. The portal can access those files and use them to remember the users data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser. ...
Changes in cytosolic Ca2+ concentration ([Ca2+]c) provide signals to control crucial events such as muscle contraction, neurotransmitter release, alterations in gene transcription and cell death (Berridge et al., 2003; Bootman et al., 2001; Orrenius et al., 2003). Ca2+ signals, physiological and pathological, are modulated by the activity of mitochondria (Berridge, 2002; Hajnoczky et al., 2000; Jacobson and Duchen, 2004). These organelles accumulate Ca2+ via an electrogenic uniporter when [Ca2+]c exceeds ∼100 nM, using the potential, ΔΨm, generated across the inner mitochondrial membrane by the activity of the electron-transport chain (Becker et al., 1980; Nicholls and Crompton, 1980). Mitochondria release Ca2+ more slowly back to the cytosol via a Na+- or H+-antiporter (Crompton et al., 1978; Rottenberg and Marbach, 1990). In this way, mitochondria act as localized [Ca2+]c buffering units and might modulate Ca2+ feedback-inhibition or activation mechanisms (Collins et al., 2000; Hajnoczky ...
Programmed cell death: regulated necrosis. During regulated necrosis, different stimuli are recognized or sensed by specific receptors on the cell surface or inside cells. The activation of the necrosome stimulates different signaling pathways leading to mitochondrial hyperpolarization, lysosomal membrane permeabilization, and generation of reactive oxygen species (ROS), leading to cellular disintegration. A recent study revealed that germanium nanoparticles trigger necrostatin-1-inhibitable cell death with a reduction of the mitochondrial membrane potential ...
Measles is caused by measles virus which is single-stranded, negative sense enveloped RNA virus. It is well known to be highly contagious. Its airborne but is spread also via direct contact with secretions. The only host of this virus is human. Each year it infects 20-40 million people around the world, one to two millions ...
The mutual relationship between mitochondrial structure and function is an emerging focus of biology and medicine. In the muscle, the Ca2+-driven contractile activity has to be dynamically matched by energy supply. Both Ca2+ homeostasis and energy metabolism rely on mitochondrial function. Based on recent evidence mitochondrial activity in ATP generation, in Ca2+ handling and even in cell death depends on continuous restructuring of the individual mitochondria in several cell types. Furthermore, Ca2+ the central regulator of muscle contraction emerges as a key signaling molecule in organellar dynamics. However, it has been difficult to study the mitochondrial fusion, fission and positioning in skeletal or cardiac muscle. Excitingly, recent advances in live cell microscopy and in the fluorescent protein technology provide a means to study mitochondrial dynamics and its signaling mechanisms in the muscle. The significance of these studies is further emphasized by the data on the possible ...
The prediction of impending collapse of deep tunnel is one of the most difficult problems. Collapse mechanism of deep tunnel in layered soils is derived using a new curved failure mechanism within the framework of upper bound theorem, and effects of seepage forces are considered. Nonlinear failure criterion is adopted in the present analysis, and the possible collapse shape of deep tunnel in the layered soils is discussed in this paper. In the layered soils, the internal energy dissipations along velocity discontinuity are calculated, and the external work rates are produced by weight, seepage forces and supporting pressure. With upper bound theorem of limit analysis, two different curve functions are proposed for the two different soil stratums. The specific shape of collapse surface is discussed, using the proposed curve functions. Effects of nonlinear coefficient, initial cohesion, pore water pressure and unit weight on potential collapse are analyzed. According to the numerical results, with ...
We have developed a molecular model to describe the structural changes and potential collapse of weak polyelectrolyte layers end-tethered to planar surfaces and spherical nanoparticles as a function of pH and divalent ion concentration. In particular, we describe the structural changes of polymer-coated nano
In this issue of Circulation Research, Das et al19 report that GSK-3 inhibitors induce dephosphorylation of VDAC, thereby reducing adenine nucleotide (such as ATP) transport across the outer mitochondrial membrane. The action of the GSK-3 inhibitors on VDAC not only preserves ATP by blocking mitochondrial consumption of ATP generated through anaerobic glycolysis but also prevents mitochondrial Ca2+ overloading and oxidative stress by reducing mitochondrial membrane potential. Interestingly, this effect of GSK-3 inhibition appears to be independent of mPTP opening.. The findings of Das et al19 suggest that inhibition of GSK-3 may facilitate hypoxic adaptation during ischemia through dephosphorylation of VDAC. Under hypoxic conditions, generation of ATP shifts from oxidative phosphorylation in the mitochondria to glycolysis in the cytoplasm, a phenomenon known as metabolic adaptation described by Louis Pasteur in the 19th century. This process is controlled by transcription factors, such as ...
This figure shows how the membrane potential can be measured by using a special voltmeter that is electrically connected to the interior of the cell via a glass microelectrode.
Goldman Sachs isnt the only trading firm facing potential losses after the bank on Tuesday flooded the U.S. stock-options market with erroneous orders. Jacob Bunge reports on The News Hub. Photo: AP.
Video created by Universidade Duke for the course Introdução à fisiologia humana. We hope you are enjoying the course! Last weeks lectures can be challenging because we introduce many concepts that may be new to you. This module will allow you ...
Physiology Test Question - A change in the membrane potential (Vm) from the resting value of -50 mV to a new value of -90 mV is referred to as:
Arsenic exposure mainly through food and water has been shown to be associated with increased incidence of numerous cancers and non-cancer harmful health. It is also used in cancer chemotherapy and treatment of several cancer types due to its apoptogenic effects in the various cancer and normal cell lines. We have already reported that liver is the storage site and important target organ in As (III) toxicity and recently, it has been suggested that hepatic toxicity of arsenic could be resulted from impairment of the liver mitochondria. In this study, interaction of As (III) with freshly isolated rat mitochondria was investigated. We determined different mitochondrial toxicity factors as well as mitochondrial sources of ROS formation using specific substrates and inhibitors following addition of As (III) to the mitochondria. Our results showed that arsenic (III) increased mitochondrial ROS formation, lipid peroxidation and mitochondrial membrane potential collapse, cytochrome c release and mitochondrial
Free Online Library: Induction of apoptosis in human pancreatic MiaPaCa-2 cells through the loss of mitochondrial membrane potential ([DELTA][[PSI].sub.m]) by Gentiana kurroo root extract and LC-ESI-MS analysis of its principal constituents.(Report) by Phytomedicine: International Journal of Phytotherapy & Phytopharmacology; Health, general Biological sciences Science and technology, general Apoptosis Analysis Research Asteridae Health aspects Lamiales Lipid peroxidation Mass spectrometry Methods Materia medica, Vegetable Pancreas Physiological aspects Plant extracts Roots (Botany) Tocopherols
Tyloxapol is reported to prevent macrophages from reacting to endotoxin. However, the intracellular responses that tyloxapol induces in macrophages are still not fully explored. Hence, the objective of this study was to evaluate the intracellular events in macrophages treated with tyloxapol and assess the antioxidant properties of tyloxapolin endotoxin-activated macrophages. Using flow cytometry, we examined intracellular responses in macrophages: reactive oxygen species (ROS) content, mitochondria membrane potential, and cell cycle profiles. We also assessed the antioxidant properties of tyloxapol in endotoxin-activated macrophages. Kinetic hydrogen peroxide production tended to decline with increasing doses. Tyloxapol produced a progressive increase followed by a decline in superoxide anion production in macrophages with increasing doses. Tyloxapol also caused unstable fluctuations in mitochondrial membrane potential. Apoptosis had developed at higher doses after 4h of incubation time. After 2 ...
This gives a simple picture of insulin resistance as a metabolic technique to limit caloric entry in to an individual cell under conditions of excess availability. NADH, tending to come from glucose, drives complex I to generate a decent inner mitochondrial membrane potential (delta psi). Feeding substrate in at other access points to the electron transport chains CoQ couple, be that electron transporting flavoprotein dehydrogenase, mtG3Pdehydrogease, NADPH dehydrogenase or others, reduces that CoQ couple and promotes reverse electron flow through complex I, superoxide generation and insulin resistance. This is the insulin resistance seen so clearly when you pay folks to over-eat, assuming you feed them crapinabag. The exact mechanism of this failure of insulin to act is not clear, but large amounts of H2O2 act at several points to inhibit the activation pathway. Of course an intramitochondrial mechanism would be really neat, or some sort of complexing of the insulin/receptor with ETC proteins. ...