scholarly journals p38 MAPK links oxidative stress to autophagy-related gene expression in cachectic muscle wasting

2010 ◽  
Vol 298 (3) ◽  
pp. C542-C549 ◽  
Author(s):  
J. M. McClung ◽  
A. R. Judge ◽  
S. K. Powers ◽  
Z. Yan

Oxidative stress is a primary trigger of cachectic muscle wasting, but the signaling pathway(s) that links it to the muscle wasting processes remains to be defined. Here, we report that activation of p38 mitogen-activated protein kinase (MAPK) (phosphorylation) and increased oxidative stress ( trans-4-hydroxy-2-nonenal protein modification) in skeletal muscle occur as early as 8 h after lipopolysaccharide (1 mg/kg) and 24 h after dexamethasone (25 mg/kg) injection (intraperitoneal) in mice, concurrent with upregulation of autophagy-related genes, Atg6, Atg7, and Atg12. Treating cultured C2C12 myotubes with oxidant hydrogen peroxide (4 h) resulted in increased p38 phosphorylation and reduced FoxO3 phosphorylation along with induced Atg7 mRNA expression without activation of NF-κ B or FoxO3a transcriptional activities. Furthermore, inhibition of p38α/β by SB202190 blocked hydrogen peroxide-induced atrophy with diminished upregulation of Atg7 and atrogenes [muscle atrophy F-box protein ( MAFbx/Atrogin-1) , muscle ring finger protein 1 ( MuRF-1), and Nedd4]. These findings provide direct evidence for p38α/β MAPK in mediating oxidative stress-induced autophagy-related genes, suggesting that p38α/β MAPK regulates both the ubiquitin-proteasome and the autophagy-lysosome systems in muscle wasting.

2011 ◽  
Vol 39 (01) ◽  
pp. 161-170 ◽  
Author(s):  
Ki Cheon Kim ◽  
In Kyung Lee ◽  
Kyoung Ah Kang ◽  
Bum Joon Kim ◽  
Daeshin Kim ◽  
...  

The ethylacetate fraction of Empetrum nigrum var. japonicum (ENE) was shown to reduce intracellular reactive oxygen species (ROS) generated by γ-radiation and activate antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and gluthathion peroxidase (GPx). ENE protected cells against radiation-induced cellular DNA damage, membrane lipid peroxidation, and protein modification, which are the main points of radiation-induced damage. In addition, ENE recovered cell viability by inhibiting apoptosis after cells were treated with radiation. ENE treatment also reduced γ-radiation induced Bax, and caspase 9 and 3 expression in irradiated cells. However, irradiated cells with ENE recovered Bcl-2 expression, which was reduced by radiation. This anti-apoptotic effect of ENE was due to the inhibition of mitogen-activated protein kinase kinase-4 (MKK4/SEK1)-c-Jun NH2-terminal kinase (JNK) cascades induced by γ-radiation. In summary, these results suggest that ENE protects cells against γ-radiation-induced oxidative stress via the reduction of ROS and attenuation of apoptosis.


2003 ◽  
Vol 2 (2) ◽  
pp. 351-361 ◽  
Author(s):  
Rebeca Alonso-Monge ◽  
Federico Navarro-García ◽  
Elvira Román ◽  
Ana I. Negredo ◽  
Blanca Eisman ◽  
...  

ABSTRACT Candida albicans mutants with mutations in mitogen-activated protein (MAP) kinase HOG1 displayed an increased sensitivity to agents producing reactive oxygen species, such as oxidants (menadione, hydrogen peroxide, or potassium superoxide), and UV light. Consistent with this finding, C. albicans Hog1 was activated not only in response to an increase in external osmolarity, as happens with its Saccharomyces cerevisiae homologue, but also in response to hydrogen peroxide. The Hog1-mediated response to oxidative stress was different from that of transcription factor Cap1, the homologue of S. cerevisiae Yap1, as shown by the different sensitivities to oxidants and the kinetics of cell death of cap1Δ, hog1, and hog1 cap1Δ mutants. Deletion of CAP1 did not influence the level of Hog1 phosphorylation, and deletion of HOG1 did not affect Cap1 nuclear localization. Moreover, we show that the HOG1 gene plays a role in chlamydospore formation, another oxygen-related morphogenetic event, as demonstrated by the fact that hog1 cells were unable to generate these thick-walled structures in several media through a mechanism different from that of the EFG1 regulator. This is the first demonstration of the role of the Hog1-mediated MAP kinase pathway in resistance to oxidative stress in pathogenic fungi, and it allows us to propose a molecular model for the oxidative stress response in C. albicans.


2005 ◽  
Vol 41 ◽  
pp. 173-186 ◽  
Author(s):  
Didier Attaix ◽  
Sophie Ventadour ◽  
Audrey Codran ◽  
Daniel Béchet ◽  
Daniel Taillandier ◽  
...  

The ubiquitin–proteasome system (UPS) is believed to degrade the major contractile skeletal muscle proteins and plays a major role in muscle wasting. Different and multiple events in the ubiquitination, deubiquitination and proteolytic machineries are responsible for the activation of the system and subsequent muscle wasting. However, other proteolytic enzymes act upstream (possibly m-calpain, cathepsin L, and/or caspase 3) and downstream (tripeptidyl-peptidase II and aminopeptidases) of the UPS, for the complete breakdown of the myofibrillar proteins into free amino acids. Recent studies have identified a few critical proteins that seem necessary for muscle wasting {i.e. the MAFbx (muscle atrophy F-box protein, also called atrogin-1) and MuRF-1 [muscle-specific RING (really interesting new gene) finger 1] ubiquitin–protein ligases}. The characterization of their signalling pathways is leading to new pharmacological approaches that can be useful to block or partially prevent muscle wasting in human patients.


1998 ◽  
Vol 3 (1) ◽  
pp. 23-27 ◽  
Author(s):  
Kathryn Z Guyton ◽  
Myriani Gorospe ◽  
Xiantao Wang ◽  
Yolanda D Mock ◽  
Gertrude C Kokkonen ◽  
...  

2018 ◽  
Vol 9 (1) ◽  
pp. 147-153 ◽  
Author(s):  
Jianying He ◽  
Wenwen Zhong ◽  
Ming Zhang ◽  
Rongping Zhang ◽  
Weiyan Hu

AbstractParkinson’s disease, the second major neurodegenerative disease, has created a great impact on the elder people. Although the mechanisms underlying Parkinson’s disease are not fully understood, considerable evidence suggests that neuro-inflammation, oxidative stress, mitochondrial dysfunction, cell proliferation, differentiation and apoptosis are involved in the disease. p38MAPK, an important member of the mitogen-activated protein family, controls several important functions in the cell, suggesting a potential pathogenic role in PD. This review provides a brief description of the role and mechanism of p38MAPK in Parkinson’s disease.


Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2611
Author(s):  
Jong Hee Im ◽  
Seungmin Son ◽  
Jae-Heung Ko ◽  
Kyung-Hwan Kim ◽  
Chung Sun An ◽  
...  

The plant mitogen-activated protein kinase (MPK) cascade, a highly conserved signal transduction system in eukaryotes, plays a crucial role in the plant’s response to environmental stimuli and phytohormones. It is well-known that nuclear translocation of MPKs is necessary for their activities in mammalian cells. However, the mechanism underlying nuclear translocation of plant MPKs is not well elucidated. In the previous study, it has been shown that soybean MPK6 (GmMPK6) is activated by phosphatidic acid (PA) and hydrogen peroxide (H2O2), which are two signaling molecules generated during salt stress. Using the two signaling molecules, we investigated how salt stress triggers its translocation to the nucleus. Our results show that the translocation of GmMPK6 to the nucleus is mediated by H2O2, but not by PA. Furthermore, the translocation was interrupted by diphenylene iodonium (DPI) (an inhibitor of RBOH), confirming that H2O2 is the signaling molecule for the nuclear translocation of GmMPK6 during salt stress.


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