Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 176
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 176
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 250
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 1034
Function: getPubMedXML
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3152
Function: GetPubMedArticleOutput_2016
File: /var/www/html/application/controllers/Detail.php
Line: 575
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 489
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Oxidative stress is a key factor in stimulating the expression of atrogenes, which are muscle atrophy-related ubiquitin ligases, in skeletal muscle, and it induces muscle atrophy during unloading. However, the effects of antioxidative nutrients on atrogene expression have not been demonstrated. We report on the inhibitory effects of polyphenols, such as epicatechin (EC), epicatechin gallate (ECg) and epigallocatechin gallate (EGCg) and quercetin, on atrogene expression up-regulated by three dimensional (3D)-clinorotation or glucocorticoid. These treatments markedly elevated the expression of atrogenes, including atrogin-1 and MuRF-1, in mouse C2C12 myoblasts and myotubes. Interestingly, EC, ECg, EGCg and quercetin significantly decreased the expression of atrogin-1 and MuRF-1 up-regulated by 3D-clinorotation, whereas they hardly affected atrogene expression induced by dexamethasone. ERK signaling is a well known MAPK pathway to mediate oxidative stress. Therefore, we also investigated the effect of these polyphenols on phosphorylation of ERK in C2C12 myotubes. As expected, EC, ECg, EGCg, and quercetin significantly suppressed phosphorylation of ERK, corresponding to the up-regulation of atrogenes induced by 3D-clinorotation. These results suggest that antioxidative nutrients, such as catechins and quercetin, suppress atrogene expression in skeletal muscle cells, possibly through the inhibition of ERK signaling. Thus, catechins and quercetin may prevent unloading-mediated muscle atrophy.
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Source |
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http://dx.doi.org/10.2152/jmi.56.26 | DOI Listing |
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