Pathological Relationship between Intracellular Superoxide Metabolism and p53 Signaling in Mice

Intracellular superoxide dismutases (SODs) maintain tissue homeostasis via superoxide metabolism. We previously reported that intracellular reactive oxygen species (ROS), including superoxide accumulation caused by cytoplasmic SOD (SOD1) or mitochondrial SOD (SOD2) insufficiency, induced p53 activation in cells. SOD1 loss also induced several age-related pathological changes associated with increased oxidative molecules in mice. To evaluate the contribution of p53 activation for SOD1 knockout (KO) (Sod1−/−) mice, we generated SOD1 and p53 KO (double-knockout (DKO)) mice. DKO fibroblasts showed increased cell viability with decreased apoptosis compared with Sod1−/− fibroblasts. In vivo experiments revealed that p53 insufficiency was not a great contributor to aging-like tissue changes but accelerated tumorigenesis in Sod1−/− mice. Furthermore, p53 loss failed to improve dilated cardiomyopathy or the survival in heart-specific SOD2 conditional KO mice. These data indicated that p53 regulated ROS-mediated apoptotic cell death and tumorigenesis but not ROS-mediated tissue degeneration in SOD-deficient models.

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Regorafenib-Attenuated, Bleomycin-Induced Pulmonary Fibrosis by Inhibiting the TGF-β1 Signaling Pathway

International Journal of Molecular Sciences ◽

10.3390/ijms22041985 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1985

Author(s):

Xiaohe Li ◽

Ling Ma ◽

Kai Huang ◽

Yuli Wei ◽

Shida Long ◽

...

Keyword(s):

Pulmonary Fibrosis ◽

Signaling Pathway ◽

Transforming Growth Factor ◽

Kinase Inhibitor ◽

In Vivo Experiments ◽

Age Related ◽

And Migration ◽

Tgf Β1

Idiopathic pulmonary fibrosis (IPF) is a fatal and age-related pulmonary disease. Nintedanib is a receptor tyrosine kinase inhibitor, and one of the only two listed drugs against IPF. Regorafenib is a novel, orally active, multi-kinase inhibitor that has similar targets to nintedanib and is applied to treat colorectal cancer and gastrointestinal stromal tumors in patients. In this study, we first identified that regorafenib could alleviate bleomycin-induced pulmonary fibrosis in mice. The in vivo experiments indicated that regorafenib suppresses collagen accumulation and myofibroblast activation. Further in vitro mechanism studies showed that regorafenib inhibits the activation and migration of myofibroblasts and extracellular matrix production, mainly through suppressing the transforming growth factor (TGF)-β1/Smad and non-Smad signaling pathways. In vitro studies have also indicated that regorafenib could augment autophagy in myofibroblasts by suppressing TGF-β1/mTOR (mechanistic target of rapamycin) signaling, and could promote apoptosis in myofibroblasts. In conclusion, regorafenib attenuates bleomycin-induced pulmonary fibrosis by suppressing the TGF-β1 signaling pathway.

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Targeting autophagy enhances atezolizumab-induced mitochondria-related apoptosis in osteosarcoma

Cell Death and Disease ◽

10.1038/s41419-021-03449-6 ◽

2021 ◽

Vol 12 (2) ◽

Author(s):

Zhuochao Liu ◽

Hongyi Wang ◽

Chuanzhen Hu ◽

Chuanlong Wu ◽

Jun Wang ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Antitumor Immunity ◽

Reactive Oxygen ◽

Oxygen Species ◽

Specific Monoclonal Antibody ◽

Osteosarcoma Cells ◽

Jnk Pathway ◽

In Vivo Experiments

AbstractIn this study, we identified the multifaceted effects of atezolizumab, a specific monoclonal antibody against PD-L1, in tumor suppression except for restoring antitumor immunity, and investigated the promising ways to improve its efficacy. Atezolizumab could inhibit the proliferation and induce immune-independent apoptosis of osteosarcoma cells. With further exploration, we found that atezolizumab could impair mitochondria of osteosarcoma cells, resulting in increased release of reactive oxygen species and cytochrome-c, eventually leading to mitochondrial-related apoptosis via activating JNK pathway. Nevertheless, the excessive release of reactive oxygen species also activated the protective autophagy of osteosarcoma cells. Therefore, when we combined atezolizumab with autophagy inhibitors, the cytotoxic effect of atezolizumab on osteosarcoma cells was significantly enhanced in vitro. Further in vivo experiments also confirmed that atezolizumab combined with chloroquine achieved the most significant antitumor effect. Taken together, our study indicates that atezolizumab can induce mitochondrial-related apoptosis and protective autophagy independently of the immune system, and targeting autophagy is a promising combinatorial approach to amplify its cytotoxicity.

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Abstract 123: Age-Related Endothelial Senescence is Driven by Thrombospondin-1-Activated NADPH Oxidase Nox1

Hypertension ◽

10.1161/hyp.66.suppl_1.123 ◽

2015 ◽

Vol 66 (suppl_1) ◽

Author(s):

Daniel N Meijles ◽

Imad Al Ghouleh ◽

Sanghamitra Sahoo ◽

Jefferson H Amaral ◽

Heather Knupp ◽

...

Keyword(s):

Oxidative Stress ◽

Nadph Oxidase ◽

Vascular Diseases ◽

Dependent Manner ◽

Wild Type ◽

Molecular Control ◽

Redox Biology ◽

Age Related ◽

P53 Activation

Organismal aging represents an independent risk factor underlying many vascular diseases, including systemic and pulmonary hypertension, and atherosclerosis. While the mechanisms driving aging are largely elusive, a steady persistent increase in tissue oxidative stress has been associated with senescence. Previously we showed TSP1 elicits NADPH oxidase (Nox)-dependent vascular smooth muscle cell oxidative stress. However mechanisms by which TSP1 affects endothelial redox biology are unknown. Here, we tested the hypothesis that TSP1 induces endothelial oxidative stress-linked senescence in aging. Using rapid autopsy disease-free human pulmonary (PA) artery, we identified a significant positive correlation between age, protein levels of TSP1, Nox1 and the cell-cycle repressor p21cip (p<0.05). Age also positively associated with increased Amplex Red-detected PA hydrogen peroxide levels (p<0.05). Moreover, treatment of human PA endothelial cells (HPAEC) with TSP1 (2.2nM; 24h) increased expression (~1.9 fold; p<0.05) and activation of Nox1 (~1.7 fold; p<0.05) compared to control, as assessed by Western blot and SOD-inhibitable cytochrome c reduction. Western blotting and immunofluorescence showed a TSP1-mediated increase in p53 activation, indicative of the DNA damage response. Moreover, TSP1 significantly increased HPAEC senescence in a p53/p21cip/Rb-dependent manner, as assessed by immunofluorescent detection of subcellular localization and senescence-associated β-galactosidase staining. To explore this pathway in vivo, middle-aged (8-10 month) wild-type and TSP1-null mice were utilized. In the TSP1-null, reduced lung senescence, oxidative stress, Nox1 levels and p21cip expression were observed compared to wild-type supporting findings in human samples and cell experiments. Finally, prophylactic treatment with specific Nox1 inhibitor NoxA1ds (10μM) attenuated TSP1-induced HPAEC ROS, p53 activation, p21cip expression and senescence. Taken together, our results provide molecular insight into the functional interplay between TSP1 and Nox1 in the regulation of endothelial senescence, with implications for molecular control of the aging process.

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The Role of BDNF on Aging-Modulation Markers

Brain Sciences ◽

10.3390/brainsci10050285 ◽

2020 ◽

Vol 10 (5) ◽

pp. 285

Author(s):

Claudio Molinari ◽

Vera Morsanuto ◽

Sara Ruga ◽

Felice Notte ◽

Mahitab Farghali ◽

...

Keyword(s):

Brain Aging ◽

Cerebral Atrophy ◽

Sirtuin 1 ◽

In Vivo Experiments ◽

Endogenous Production ◽

Age Related ◽

Protection Mechanisms ◽

Endogenous Protection

An important link between brain aging and a class of growth/survival factors called neurotrophins has recently been demonstrated. In particular, brain-derived neurotrophic factor (BDNF) plays a fundamental role during age-related synaptic loss, preventing cerebral atrophy and cognitive decline. The aim of the present study was to investigate whether the use of low dose BDNF sequentially kinetic activated (SKA) was able to counteract some mechanisms underlying the degeneration and aging of nervous tissue by increasing endogenous protection mechanisms. Both in vitro and in vivo experiments were performed to assess the ability of BDNF SKA to protect and regenerate survival-related molecular pathways, studying intestinal absorption in vitro and brain function in vivo. Our pioneering results show that BDNF SKA is able to induce the endogenous production of BDNF, using its receptor TrkB and influencing the apolipoprotein E expression. Moreover, BDNF SKA exerted effects on β-Amyloid and Sirtuin 1 proteins, confirming the hypothesis of a fine endogenous regulatory effect exerted by BDNF SKA in maintaining the health of both neurons and astrocytes. For this reason, a change in BDNF turnover is considered as a positive factor against brain aging.

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Grade-targeted nanoparticles for improved hypoxic tumor microenvironment and enhanced photodynamic cancer therapy

Nanomedicine ◽

10.2217/nnm-2020-0096 ◽

2021 ◽

Vol 16 (3) ◽

pp. 221-235 ◽

Cited By ~ 1

Author(s):

Ying-kai Tao ◽

Xiao-yang Hou ◽

Huan Gao ◽

Xin Zhang ◽

Feng-mei Zuo ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Tumor Microenvironment ◽

Aminolevulinic Acid ◽

Double Emulsion ◽

Reactive Oxygen ◽

Oxygen Species ◽

In Vivo Experiments ◽

Limited Diffusion

Background: The hypoxia of the tumor microenvironment (TME), low transfer efficiency of photosensitizers and limited diffusion distance of reactive oxygen species restrict the application of photodynamic therapy (PDT). Aim: To produce TME-responsive and effective nanoparticles for sensitizing PDT. Materials & methods: CD44 and mitochondria grade-targeted hyaluronic acid (HA)-triphenylphosphine (TPP)-aminolevulinic acid (ALA)-catalase (CAT) nanoparticles (HTACNPs) were synthesized via a modified double-emulsion method. In vitro and in vivo experiments were performed to investigate the antitumor efficacy of HTACNP-mediated PDT. Results: HTACNPs specifically targeted MV3 cells and the mitochondria and produced O2 to relieve TME hypoxia. HTACNP-mediated PDT produced reactive oxygen species to induce irreversible cell apoptosis. HTACNP-PDT inhibited melanoma growth effectively in vivo. Conclusion: HTACNP-mediated PDT improved TME hypoxia and effectively enhanced PDT for cancer.

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The Role of Reactive Oxygen Species in the Light-Induced Deformation of DNA

Zeitschrift für Naturforschung B ◽

10.1515/znb-1984-0922 ◽

1984 ◽

Vol 39 (9) ◽

pp. 1276-1280 ◽

Cited By ~ 1

Author(s):

R. Baumann ◽

M. Herrmann ◽

H. Parlar

Keyword(s):

Reactive Oxygen Species ◽

Excited States ◽

Reactive Oxygen ◽

Oxygen Species ◽

In Vivo Experiments ◽

Pyrimidine Bases ◽

Effect Of Oxygen

Dimerizations and reactions with water of pyrimidine bases are the primary steps held responsible for the deformation of DNA at short wavelengths in vitro and in vivo experiments. However the influence of oxygen in combination with water on the UV deformation at wavelengths representative for troposphere is evident from the observed data and both together are needed to change the DNA structure. The only plausible explanation for the effect of oxygen is the formation of reactive oxygen species during the UV irradiation of DNA. In the present work the deformation of DNA by different oxygen species like singlet oxygen (1O2), superoxideanion (O2-), hydroxyradical (·OH), ozone (O3) and hydrogenperoxide (H2O2) is excluded with the help of chemical-trapping experiments. The photo-induced transformation proceeds via excited states of DNA. which react with groundstate oxygen to afford peroxide.

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Eye Vessel Compliance as a Function of Intraocular and Arterial Pressure and Eye Compliance

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80245 ◽

2012 ◽

Author(s):

Adan Villamarin ◽

Sylvain Roy ◽

Nikolaos Stergiopulos

Keyword(s):

Arterial Pressure ◽

Vascular Network ◽

Age Related Macular Degeneration ◽

Pressure Amplitude ◽

Vascular Compliance ◽

In Vivo Experiments ◽

Age Related ◽

Volume Curve

Age-related macular degeneration (AMD) is a disease affecting the eye and is likely related to an increase in eye vascular rigidity. Developing methodologies to measure eye vessels compliance is of interest, as this may prove useful in diagnosing retinal diseases such as AMD. In vitro and in vivo experiments were conducted on rabbit eyes to validate the methodology proposed. Therefore the compliance of the eye vessels was estimated indirectly from the measurements of intraocular pressure (IOP), blood pressure and the compliance of the eyeball (OC) and compared to the pressure-volume curve. The method to estimate the vascular compliance of the eye was then tested under normal conditions and after administration of norepinephrine in vivo, which induced a vasoconstriction leading to reduction in vascular compliance. In vitro comparison of direct versus indirect estimates of compliance showed a difference that was not significant (0.075 vs. 0.077 μl/mmHg, p = 0.86). Results from the in vivo study indicated that norepinephrine significantly increased the arterial pulse pressure amplitude while compliance of vascular network of the eye decreased from 0.18 ± 0.12 μl/mmHg to 0.10 ± 0.08 μl/mmHg (p = 0.001). These results indicate that the compliance of the vascular network can be predicted using the IOP, the arterial pressure and the OC of the eyeball.

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A Simple and a Reliable Method to Quantify Antioxidant Activity In Vivo

Antioxidants ◽

10.3390/antiox8050142 ◽

2019 ◽

Vol 8 (5) ◽

pp. 142 ◽

Cited By ~ 6

Author(s):

María Pilar de Torre ◽

Rita Yolanda Cavero ◽

María Isabel Calvo ◽

José Luis Vizmanos

Keyword(s):

Antioxidant Activity ◽

Green Tea ◽

Reliable Method ◽

Positive Control ◽

Negative Control ◽

In Vivo Model ◽

In Vivo Experiments ◽

Age Related

The characterization of compounds with antioxidant activity is of great interest due to their ability to reduce reactive oxygen species production and, therefore, prevent some age-related diseases. Its antioxidant capacity can be analyzed by different methods both in vitro and in vivo. Caenorhabditis elegans is an in vivo model widely used in ageing research. Until now, available tests analyze functional effects in the worms, so the antioxidant activity of the compound is indirectly monitored. We have developed a simple and a reliable method to quantify internal antioxidant activity in vivo. To validate this method, we analyzed an aqueous green tea extract and two other compounds with a well-known antioxidant activity and without this activity. The results obtained (EC50 green tea = 21.76 ± 1.28 µg/mL; EC50 positive control = 8.50 ± 0.33 µg/mL; negative control EC50 > 500 µg/mL) can help in the design of further in vivo experiments. Thus, our method can be used as a previous screening capable of reducing the gap between in vitro and in vivo assays.

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In vitro effect of N-acetylcysteine on hepatocyte injury caused by dichlorodiphenyltrichloroethane and its metabolites

Human & Experimental Toxicology ◽

10.1177/0960327113482954 ◽

2013 ◽

Vol 33 (1) ◽

pp. 41-53 ◽

Cited By ~ 6

Author(s):

J J van Tonder ◽

M Gulumian ◽

A D Cromarty ◽

V Steenkamp

Keyword(s):

Apoptotic Cell ◽

Ros Generation ◽

Oxygen Species ◽

Cellular Viability ◽

Cytotoxic Effects ◽

Hepatocyte Injury ◽

Intracellular Changes ◽

Vitro Effect

The organochlorine pesticide, dichlorodiphenyltrichloroethane (DDT), is still used to combat the spread of malaria in several developing countries despite its accumulation and known hepatotoxic effects that have been demonstrated both in vitro and in vivo. N-Acetylcysteine (NAC) is a recognized hepatoprotective agent that has been reported to reduce hepatotoxicity initiated by many different compounds. The aim of this study was to determine whether NAC could counter in vitro hepatocyte injury induced by DDT or its two major metabolites, dichlorodiphenyldichloroethylene and dichlorodiphenyldichloroethane. HepG2 cell cultures were used to assess the following parameters of toxicity: cellular viability, intracellular levels of reactive oxygen species (ROS), mitochondrial membrane potential and initiation of apoptosis. None of the three test compounds induced ROS generation, yet exposure to any of the three compounds produced mitochondrial hyperpolarization, which was countered by NAC pretreatment. All three test compounds also induced apoptotic cell death, which was inhibited by NAC. Despite NAC counteracting some adverse intracellular changes due to organochlorine exposure, it appeared to aggravate the cytotoxic effects of the organochlorine compounds at low test concentrations. As the same outcome may also occur in vivo, results from the present study raise concern about the use of NAC as treatment for DDT-induced hepatotoxicity.

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Natural extract and its fractions isolated from the marine bacterium Pseudoalteromonas flavipulchra STILL-33 have antioxidant and antiaging activities in Schizosaccharomyces pombe

FEMS Yeast Research ◽

10.1093/femsyr/foaa014 ◽

2020 ◽

Vol 20 (3) ◽

Cited By ~ 1

Author(s):

Muhammad Eka Prastya ◽

Rika Indri Astuti ◽

Irmanida Batubara ◽

Hiroshi Takagi ◽

Aris Tri Wahyudi

Keyword(s):

Schizosaccharomyces Pombe ◽

Fission Yeast ◽

Aging Process ◽

Marine Bacterium ◽

Mitochondrial Activity ◽

Oxygen Species ◽

Related Disease ◽

Age Related

ABSTRACT Investigations into the potential for pharmacological inhibition of the aging process and the onset of age-related disease are increasingly garnering attention. Here, we analyzed the antiaging properties of natural compounds derived from several marine bacteria in vitro and in vivo using the fission yeast Schizosaccharomyces pombe. The Pseudoalteromonas flavipulchra STILL-33 extract exhibited high antioxidant and antiglycation activities in vitro. We then characterized two antioxidant active fractions isolated from this extract. In addition, we showed that the P. flavipulchra STILL-33 extract or either of its two active fractions (Fractions 1 and 2) could extend the longevity of fission yeast. Moreover, the particular extract and two active fractions were found to induce mitochondrial activity and to delay the G1 phase of the fission yeast cell cycle, perhaps by improving the aging process. The P. flavipulchra STILL-33 extract and Fraction 1 also increased the expression of the catalase-encoding ctt1+ gene and thereby decreased the reactive oxygen species level. Structural analysis showed that Fraction 1 was dominated by l-arginine and ipriflavone, and we showed indeed that the two corresponding commercial products increase the fission yeast lifespan. As for Fraction 2 was identified as the putative structure of butamben. Together, these results should facilitate the discovery of additional antiaging compounds from P. flavipulchra and ultimately the development of novel antiaging compounds for pharmaceutical use.

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