Interaction of CuO nanoparticles with plant cells: internalization, oxidative stress, electron transport chain disruption, and toxicogenomic responses

2018 ◽  
Vol 5 (10) ◽  
pp. 2269-2281 ◽  
Author(s):  
Yanhui Dai ◽  
Zhenyu Wang ◽  
Jian Zhao ◽  
Lili Xu ◽  
Lina Xu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Electron Transport ◽  
Nicotiana Tabacum ◽  
Electron Transport Chain ◽  
Plant Cells ◽  
Cuo Nanoparticles ◽  
Bright Yellow ◽  
Transport Chain

This study investigated the toxicity of CuO nanoparticles (NPs) to Nicotiana tabacum L. cv. Bright Yellow-2 (BY-2) cells.

scholarly journals Tissue Factor Decryption By Oxidative Stress-Induced Lipid Peroxidation: Potential Mechanisms

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 125-125
Author(s):  
Shabbir Ansari ◽  
Usha R Pendurthi ◽  
L. Vijaya Mohan Rao
Keyword(s):  
Oxidative Stress ◽  
Electron Transport ◽  
P38 Mapk ◽  
Electron Transport Chain ◽  
Thioredoxin Reductase ◽  
Dependent Manner ◽  
Mapk Activation ◽  
Downstream Signaling ◽  
Transport Chain

Abstract Cellular lipid peroxidation is known to contribute to the initiation and propagation of atherothrombosis. Recently, we showed that 4-hydroxynonenal (HNE), one of the most abundant reactive aldehydes generated from the oxidation of ω-6 fatty acids, enhanced tissue factor (TF) activity on monocytic cells by externalizing phosphatidylserine (PS) in p38 MAPK activation-dependent manner. However, at present, the link between HNE-induced oxidative stress and p38 MAPK activation and the relation of p38 MAPK activation to PS externalization is not fully known. In the present study, we investigated the role of mitochondrial electron transport chain and reactive oxygen species (ROS) generation in HNE-mediated TF decryption. In addition, we also investigated the thioredoxin reductase-thioredoxin-ASK-1 axis in regulating p38 MAPK activation and PS externalization in decrypting TF. To elucidate potential mechanisms of HNE-induced TF decryption, we first determined the role of specific mitochondrial electron transport chain complexes in regulating TF activity. Since THP-1 cells used in the study had a measurable basal TF activity, they were not further treated with LPS or other agonists to induce TF synthesis. The electron transport chain in these cells was disrupted by specific inhibitors and cell surface TF activity was measured by factor X activation assay. Inhibition of complex I and complex IV by rotenone and sodium azide, respectively, enhanced the procoagulant activity of basal level TF. However, the inhibition of complex I and IV had no significant effect on the HNE-mediated increase in TF activity. Interestingly, inhibition of ATP synthase/complex V by oligomycin significantly inhibited the HNE-mediated enhanced TF activity, indicating that HNE-mediated TF decryption may involve the generation of ATP. In agreement with earlier published studies in monocytes/macrophages, stimulation of THP-1 cells with ATP increased cell surface TF activity. However, at present, it is yet to be shown that HNE treatment actually increased the production of ATP and that this ATP is responsible for the HNE-mediated TF decryption. It is also possible that HNE, either through a generation of ROS in mitochondria or directly, can affect the activity of thioredoxin either by intracellular signaling or by directly forming an adduct with it. Therefore, we next investigated the effect of HNE on the activity of thioredoxin reductase, the enzyme known to regulate thioredoxin activity in the cell. Our data showed that HNE treatment inhibited the activity of thioredoxin reductase in a concentration-dependent manner, 40 µM of HNE inhibiting 50% of the activity and a complete inhibition at 80µM of HNE. To further determine the downstream signaling cascade involved in the PS externalization and TF decryption on exposure to HNE, we analyzed the effect of HNE on the activation of MKK3 and MKK6, the protein kinases known to activate p38 MAPK and the downstream signaling activator of thioredoxin/thioredoxin reductase pathway. HNE treatment increased the phosphorylation of MKK3 and MKK6 in a time-dependent manner. In summary, our data suggest that HNE may mediate TF decryption via modulation of thioredoxin/thioredoxin reductase system, which results in activation of MKK3/MKK6, which in turn activates p38 MAPK that is responsible for PS externalization. The study highlights the potential role of oxidative stress in regulating TF activity in thrombotic disorders and provides a mechanistic link between disorders associated with cellular oxidative stress and thrombosis. Disclosures No relevant conflicts of interest to declare.

Abstract 665: Cryofluorescence 3D Imaging Shows Mutation of p67phox Improves Metabolic Function and Reduces Oxidative Stress in the Renal Medulla of the Dahl Salt-sensitive Rat

Hypertension ◽  
2014 ◽  
Vol 64 (suppl_1) ◽  
Author(s):  
Allen W Cowley ◽  
Fahimeh Salehpour ◽  
Chun Yang ◽  
Theresa Kurth ◽  
Mahsa Ranji
Keyword(s):  
Oxidative Stress ◽  
Electron Transport ◽  
Electron Transport Chain ◽  
Substantial Reduction ◽  
Renal Medulla ◽  
Metabolic Function ◽  
Protective Effects ◽  
3D Images ◽  
Transport Chain ◽  
And Oxidative Stress

The Dahl salt-sensitive (SS) rat exhibits increased renal production of reactive oxygen species (ROS) especially in the renal outer medulla (OM) which is known to contribute importantly to the salt-induced hypertension. We have identified increased expression of the p67 phox cytosolic subunit of NAD(P)H oxidase and enhanced enzyme activity in the OM of Dahl salt-sensitive (SS). We found that ZFN knock down of the NADPH-oxidase cytosolic subunit p67 phox in SS rats (SS p67phox-/- ) resulted in a 40% reduction of hypertension and a substantial reduction of renal injury. To determine whether these protective effects were associated with alterations of regional metabolism and oxidative stress, a custom designed cryoimager was used to acquire multi-channel fluorescent images of sequential serial sections with a z-resolution of 30 μm yielding 400 slices per kidney. Computer reconstruction of the stacked sections provided a 3D image of regional changes of metabolic function and oxidative stress within the kidney. Kidneys obtained from SS and SS p67phox-/- rats fed a high salt diet (4% NaCl) for 21 days were flash frozen in liquid N 2 and fluorescent images of the mitochondrial electron transport chain carriers NADH and FAD were acquired. The naturally fluorescent NADH and FAD levels were acquired to provide a 3D representation of the metabolic state of the tissue and oxidative stress. The mean NADH redox ratio (NADH/FAD RR) was significantly higher in kidneys of SS p67phox-/- rats (1.46 ± 0.11 NADH/FAD RR; n=7) compared to SS kidneys (1.00 ± 0.07 NADH/FAD RR; n=4). This represents an average 46% increase in the electron transport chain metabolic activity and a reduction of oxidative stress in kidneys of SS p67phox-/- rats compared to the SS kidneys. Importantly, this was observed only in the region of the renal medulla as revealed by the 3D images of these kidneys. We conclude that p67(phox) is critically involved in cell energetics and ROS production in the renal medulla.

scholarly journals Electron transport chain dysfunction in neonatal pressure-overload hypertrophy precedes cardiomyocyte apoptosis independent of oxidative stress

2010 ◽  
Vol 139 (6) ◽  
pp. 1609-1617 ◽  
Author(s):  
Eric R. Griffiths ◽  
Ingeborg Friehs ◽  
Elisabeth Scherr ◽  
Dimitrios Poutias ◽  
Francis X. McGowan ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Electron Transport ◽  
Electron Transport Chain ◽  
Pressure Overload ◽  
Cardiomyocyte Apoptosis ◽  
Transport Chain

scholarly journals Transcriptomic and Functional Analyses of Mitochondrial Dysfunction in Pressure Overload‐Induced Right Ventricular Failure

2021 ◽  
Vol 10 (4) ◽  
Author(s):  
HyunTae V. Hwang ◽  
Nefthi Sandeep ◽  
Ramesh V. Nair ◽  
Dong‐Qing Hu ◽  
Mingming Zhao ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Electron Transport ◽  
Mitochondrial Dysfunction ◽  
Electron Transport Chain ◽  
Mitochondrial Fission ◽  
Pressure Overload ◽  
Energy Generation ◽  
Complex Congenital Heart Disease ◽  
Chain Complexes ◽  
Transport Chain

Background In complex congenital heart disease patients such as those with tetralogy of Fallot, the right ventricle (RV) is subject to pressure overload, leading to RV hypertrophy and eventually RV failure. The mechanisms that promote the transition from stable RV hypertrophy to RV failure are unknown. We evaluated the role of mitochondrial bioenergetics in the development of RV failure. Methods and Results We created a murine model of RV pressure overload by pulmonary artery banding and compared with sham‐operated controls. Gene expression by RNA‐sequencing, oxidative stress, mitochondrial respiration, dynamics, and structure were assessed in pressure overload‐induced RV failure. RV failure was characterized by decreased expression of electron transport chain genes and mitochondrial antioxidant genes (aldehyde dehydrogenase 2 and superoxide dismutase 2) and increased expression of oxidant stress markers (heme oxygenase, 4‐hydroxynonenal). The activities of all electron transport chain complexes decreased with RV hypertrophy and further with RV failure (oxidative phosphorylation: sham 552.3±43.07 versus RV hypertrophy 334.3±30.65 versus RV failure 165.4±36.72 pmol/(s×mL), P <0.0001). Mitochondrial fission protein DRP1 (dynamin 1‐like) trended toward an increase, while MFF (mitochondrial fission factor) decreased and fusion protein OPA1 (mitochondrial dynamin like GTPase) decreased. In contrast, transcription of electron transport chain genes increased in the left ventricle of RV failure. Conclusions Pressure overload‐induced RV failure is characterized by decreased transcription and activity of electron transport chain complexes and increased oxidative stress which are associated with decreased energy generation. An improved understanding of the complex processes of energy generation could aid in developing novel therapies to mitigate mitochondrial dysfunction and delay the onset of RV failure.

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