Abstract 5379: Ciclopirox induces autophagy through reactive oxygen species-mediated inhibition of mTOR signaling pathway

8-gingerol (8-Gin) is the series of phenolic substance that is extracted from ginger. Although many studies have revealed that 8-Gin has multiple pharmacological properties, the possible underlying mechanisms of 8-Gin against myocardial fibrosis (MF) remains unclear. The study examined the exact role and potential mechanisms of 8-Gin against isoproterenol (ISO)-induced MF. Male mice were intraperitoneally injected with 8-Gin (10 and 20 mg/kg/d) and concurrently subcutaneously injected with ISO (10 mg/kg/d) for 2 weeks. Electrocardiography, pathological heart morphology, myocardial enzymes, reactive oxygen species (ROS) generation, degree of apoptosis, and autophagy pathway-related proteins were measured. Our study observed 8-Gin significantly reduced J-point elevation and heart rate. Besides, 8-Gin caused a marked decrease in cardiac weight index and left ventricle weight index, serum levels of creatine kinase and lactate dehydrogenase (CK and LDH, respectively), ROS generation, and attenuated ISO-induced pathological heart damage. Moreover, treatment with 8-Gin resulted in a marked decrease in the levels of collagen types I and III and TGF-β in the heart tissue. Our results showed 8-Gin exposure significantly suppressed ISO-induced autophagosome formation. 8-Gin also could lead to down-regulation of the activities of matrix metalloproteinases-9 (MMP-9), Caspase-9, and Bax protein, up-regulation of the activity of Bcl-2 protein, and alleviation of cardiomyocyte apoptosis. Furthermore, 8-Gin produced an obvious increase in the expressions of the PI3K/Akt/mTOR signaling pathway-related proteins. Our data showed that 8-Gin exerted cardioprotective effects on ISO-induced MF, which possibly occurred in connection with inhibition of ROS generation, apoptosis, and autophagy via modulation of the PI3K/Akt/mTOR signaling pathway.

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Nanoparticles induce autophagy via mTOR pathway inhibition and reactive oxygen species generation

Nanomedicine ◽

10.2217/nnm-2019-0387 ◽

2020 ◽

Vol 15 (14) ◽

pp. 1419-1435

Author(s):

Lu Jia ◽

Shuang-Li Hao ◽

Wan-Xi Yang

Keyword(s):

Reactive Oxygen Species ◽

Physicochemical Properties ◽

Signaling Pathway ◽

Human Body ◽

Reactive Oxygen Species Generation ◽

Reactive Oxygen ◽

Mtor Pathway ◽

Oxygen Species ◽

Mtor Signaling Pathway ◽

Pathway Inhibition

Due to their unique physicochemical properties, nanoparticles (NPs) have been increasingly developed for use in various fields. However, there has been both growing negative concerns with toxicity and positive realization of opportunities in nanomedicine, coming from the growing understanding of the associations between NPs and the human body, particularly relating to their cellular autophagic effects. This review summarizes NP-induced autophagy via the modulation of the mTOR signaling pathway and other associated signals including AMPK and ERK and also demonstrates how reactive oxygen species generation greatly underlies the regulation processes. The perspectives in this review aim to contribute to NP design, particularly in consideration of nanotoxicity and the potential for the precise application of NPs in nanomedicine.

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Reactive oxygen species rescue regeneration after silencing the MAPK–ERK signaling pathway in Schmidtea mediterranea

Scientific Reports ◽

10.1038/s41598-020-79588-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

V. Jaenen ◽

S. Fraguas ◽

K. Bijnens ◽

M. Heleven ◽

T. Artois ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Signaling Pathway ◽

Reactive Oxygen ◽

Light Therapy ◽

Erk Signaling ◽

Model Organisms ◽

Ros Production ◽

Oxygen Species ◽

Planarian Regeneration ◽

Egfr Signaling Pathway

AbstractDespite extensive research on molecular pathways controlling the process of regeneration in model organisms, little is known about the actual initiation signals necessary to induce regeneration. Recently, the activation of ERK signaling has been shown to be required to initiate regeneration in planarians. However, how ERK signaling is activated remains unknown. Reactive Oxygen Species (ROS) are well-known early signals necessary for regeneration in several models, including planarians. Still, the probable interplay between ROS and MAPK/ERK has not yet been described. Here, by interfering with major mediators (ROS, EGFR and MAPK/ERK), we were able to identify wound-induced ROS, and specifically H2O2, as upstream cues in the activation of regeneration. Our data demonstrate new relationships between regeneration-related ROS production and MAPK/ERK activation at the earliest regeneration stages, as well as the involvement of the EGFR-signaling pathway. Our results suggest that (1) ROS and/or H2O2 have the potential to rescue regeneration after MEK-inhibition, either by H2O2-treatment or light therapy, (2) ROS and/or H2O2 are required for the activation of MAPK/ERK signaling pathway, (3) the EGFR pathway can mediate ROS production and the activation of MAPK/ERK during planarian regeneration.

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Protective Effects of Gintonin on Reactive Oxygen Species-Induced HT22 Cell Damages: Involvement of LPA1 Receptor-BDNF-AKT Signaling Pathway

Molecules ◽

10.3390/molecules26144138 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4138

Author(s):

Yeon-Jin Cho ◽

Sun-Hye Choi ◽

Ra-Mi Lee ◽

Han-Sung Cho ◽

Hyewhon Rhim ◽

...

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Signaling Pathway ◽

Reactive Oxygen ◽

Akt Signaling ◽

Atp Depletion ◽

Oxygen Species ◽

Akt Signaling Pathway ◽

Neuroprotective Effects ◽

Lpa1 Receptor

Gintonin is a kind of ginseng-derived glycolipoprotein that acts as an exogenous LPA receptor ligand. Gintonin has in vitro and in vivo neuroprotective effects; however, little is known about the cellular mechanisms underlying the neuroprotection. In the present study, we aimed to clarify how gintonin attenuates iodoacetic acid (IAA)-induced oxidative stress. The mouse hippocampal cell line HT22 was used. Gintonin treatment significantly attenuated IAA-induced reactive oxygen species (ROS) overproduction, ATP depletion, and cell death. However, treatment with Ki16425, an LPA1/3 receptor antagonist, suppressed the neuroprotective effects of gintonin. Gintonin elicited [Ca2⁺]i transients in HT22 cells. Gintonin-mediated [Ca2⁺]i transients through the LPA1 receptor-PLC-IP3 signaling pathway were coupled to increase both the expression and release of BDNF. The released BDNF activated the TrkB receptor. Induction of TrkB phosphorylation was further linked to Akt activation. Phosphorylated Akt reduced IAA-induced oxidative stress and increased cell survival. Our results indicate that gintonin attenuated IAA-induced oxidative stress in neuronal cells by activating the LPA1 receptor-BDNF-TrkB-Akt signaling pathway. One of the gintonin-mediated neuroprotective effects may be achieved via anti-oxidative stress in nervous systems.

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Bioglass promotes wound healing by inhibiting endothelial cell pyroptosis through regulation of the connexin 43/reactive oxygen species (ROS) signaling pathway

Laboratory Investigation ◽

10.1038/s41374-021-00675-6 ◽

2021 ◽

Author(s):

Kailun Zhang ◽

Bo Chai ◽

Hao Ji ◽

liuqing Chen ◽

Yanbing Ma ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Wound Healing ◽

Endothelial Cell ◽

Signaling Pathway ◽

Connexin 43 ◽

Reactive Oxygen ◽

Oxygen Species ◽

Ros Signaling

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Oxidative Stressors Modify the Response of Streptococcus mutans to Its Competence Signal Peptides

Applied and Environmental Microbiology ◽

10.1128/aem.01345-17 ◽

2017 ◽

Vol 83 (22) ◽

Cited By ~ 9

Author(s):

Matthew De Furio ◽

Sang Joon Ahn ◽

Robert A. Burne ◽

Stephen J. Hagen

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Dental Caries ◽

Signaling Pathway ◽

Streptococcus Mutans ◽

Reactive Oxygen ◽

Oxygen Species ◽

Oral Biofilm ◽

Genetic Competence ◽

Content Type

ABSTRACTThe dental caries pathogenStreptococcus mutansis continually exposed to several types of stress in the oral biofilm environment. Oxidative stress generated by reactive oxygen species has a major impact on the establishment, persistence, and virulence ofS. mutans. Here, we combined fluorescent reporter-promoter fusions with single-cell imaging to study the effects of reactive oxygen species on activation of genetic competence inS. mutans. Exposure to paraquat, which generates superoxide anion, produced a qualitatively different effect on activation of expression of the gene for the master competence regulator, ComX, than did treatment with hydrogen peroxide (H2O2), which can yield hydroxyl radical. Paraquat suppressed peptide-mediated induction ofcomXin a progressive and cumulative fashion, whereas the response to H2O2displayed a strong threshold behavior. Low concentrations of H2O2had little effect on induction ofcomXor the bacteriocin genecipB, but expression of these genes declined sharply if extracellular H2O2exceeded a threshold concentration. These effects were not due to decreased reporter gene fluorescence. Two different threshold concentrations were observed in the response to H2O2, depending on the gene promoter that was analyzed and the pathway by which the competence regulon was stimulated. The results show that paraquat and H2O2affect theS. mutanscompetence signaling pathway differently, and that some portions of the competence signaling pathway are more sensitive to oxidative stress than others.IMPORTANCEStreptococcus mutansinhabits the oral biofilm, where it plays an important role in the development of dental caries. Environmental stresses such as oxidative stress influence the growth ofS. mutansand its important virulence-associated behaviors, such as genetic competence.S. mutanscompetence development is a complex behavior that involves two different signaling peptides and can exhibit cell-to-cell heterogeneity. Although oxidative stress is known to influenceS. mutanscompetence, it is not understood how oxidative stress interacts with the peptide signaling or affects heterogeneity. In this study, we used fluorescent reporters to probe the effect of reactive oxygen species on competence signaling at the single-cell level. Our data show that different reactive oxygen species have different effects onS. mutanscompetence, and that some portions of the signaling pathway are more acutely sensitive to oxidative stress than others.

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