{"id":180,"date":"2012-01-05T16:26:00","date_gmt":"2012-01-05T16:26:00","guid":{"rendered":"http:\/\/lucasgferreira.wordpress.com\/2012\/01\/05\/chronic-hypobaric-hypoxia-mediated-skeletal-muscle-atrophy-role-of-ubiquitin-proteasome-pathway-and-calpains"},"modified":"2012-01-05T16:26:00","modified_gmt":"2012-01-05T16:26:00","slug":"chronic-hypobaric-hypoxia-mediated-skeletal-muscle-atrophy-role-of-ubiquitin-proteasome-pathway-and-calpains","status":"publish","type":"post","link":"https:\/\/blog.ufes.br\/lucasgf\/?p=180","title":{"rendered":"Chronic hypobaric hypoxia mediated skeletal muscle atrophy: role of ubiquitin-proteasome pathway and calpains"},"content":{"rendered":"
Este trabalho de Chaudhary et al. auxilia na compreens\u00e3o dos efeitos da altitude sobre a musculatura esquel\u00e9tica. Apesar do aumento da taxa de s\u00edntese prot\u00e9ica em ~1,5 vezes, a prote\u00f3lise aumento cerca de 5 vezes. Os sistemas ubiquitina proteassoma e dependente das calpa\u00ednas paracem atuar de forma importante para estes efeitos. Tais efeitos ocorreram em paralelo \u00e0 perda de massa muscular dos animais e degrada\u00e7\u00e3o de prote\u00ednas, especialmente prote\u00ednas miofibrilares.<\/i><\/div>\n

<\/i><\/div>\n
Chronic hypobaric hypoxia mediated skeletal muscle atrophy: role of ubiquitin-proteasome pathway and calpains<\/b><\/span><\/p>\n
<\/div>\n<\/div>\n
Mol Cell Biochem.<\/a> 2012 Jan 4. [Epub ahead of print]<\/div>\n

<\/h1>\n

Chaudhary P<\/a>,<\/span> <\/span>Suryakumar G<\/a>,<\/span> <\/span>Prasad R<\/a>,<\/span> <\/span>Singh SN<\/a>,<\/span> <\/span>Ali S<\/a>,<\/span> <\/span>Ilavazhagan G<\/a>.<\/span><\/h1>\n
\n

Source<\/h3>\n
Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, New Delhi, 110054, India.<\/div>\n<\/div>\n
\n

Abstract<\/h3>\n
<\/div>\n
The most frequently reported symptom of exposure to high altitude is loss of body mass and decreased performance which has been attributed to altered protein metabolism affecting skeletal muscles mass. The present study explores the mechanism of chronic hypobaric hypoxia mediated skeletal muscle wasting by evaluating changes in protein turnover and various proteolytic pathways. Male Sprague-Dawley rats weighing about 200 g were exposed to hypobaric hypoxia (7,620 m) for different durations of exposure. Physical performance of rats was measured by treadmill running experiments. Protein synthesis, protein degradation rates were determined by (14)C-Leucine incorporation and tyrosine release, respectively. Chymotrypsin-like enzyme activity of the ubiquitin-proteasome pathway and calpains were studied fluorimetrically as well as using western blots. Declined physical performance by more than 20%, in terms of time taken in exhaustion on treadmill, following chronic hypobaric hypoxia was observed. Compared to 1.5-fold increase in protein synthesis, the increase in protein degradation was much higher (five-folds), which consequently resulted in skeletal muscle mass loss. Myofibrillar protein level declined from 46.79 \u00b1 1.49 mg\/g tissue at sea level to 37.36 \u00b1 1.153 (P < 0.05) at high altitude. However, the reduction in sarcoplasmic proteins was less as compared to myofibrillar protein. Upregulation of Ub-proteasome pathway (five-fold over control) and calpains (three-fold) has been found to be important factors for the enhanced protein degradation rate. The study provided strong evidences suggesting that elevated protein turnover rate lead to skeletal muscle atrophy under chronic hypobaric hypoxia via ubiquitin-proteasome pathway and calpains.<\/div>\n
<\/div>\n
Pubmed: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/22215202<\/a><\/div>\n<\/div>\n
<\/div>\n","protected":false},"excerpt":{"rendered":"

Este trabalho de Chaudhary et al. auxilia na compreens\u00e3o dos efeitos da altitude sobre a musculatura esquel\u00e9tica. Apesar do aumento da taxa de s\u00edntese prot\u00e9ica em ~1,5 vezes, a prote\u00f3lise aumento cerca de 5 vezes. Os sistemas ubiquitina proteassoma e … Continue lendo →<\/span><\/a><\/p>\n","protected":false},"author":9,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"_uag_custom_page_level_css":"","footnotes":""},"categories":[21,27,34,36],"tags":[],"class_list":["post-180","post","type-post","status-publish","format-standard","hentry","category-fisiologia","category-musculo","category-paper","category-plasticidade-muscular"],"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false,"post-thumbnail":false},"uagb_author_info":{"display_name":"Lucas Guimar\u00e3es Ferreira","author_link":"https:\/\/blog.ufes.br\/lucasgf\/?author=9"},"uagb_comment_info":8,"uagb_excerpt":"Este trabalho de Chaudhary et al. auxilia na compreens\u00e3o dos efeitos da altitude sobre a musculatura esquel\u00e9tica. Apesar do aumento da taxa de s\u00edntese prot\u00e9ica em ~1,5 vezes, a prote\u00f3lise aumento cerca de 5 vezes. Os sistemas ubiquitina proteassoma e … Continue lendo →","_links":{"self":[{"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=\/wp\/v2\/posts\/180","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=180"}],"version-history":[{"count":0,"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=\/wp\/v2\/posts\/180\/revisions"}],"wp:attachment":[{"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=180"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=180"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.ufes.br\/lucasgf\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=180"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}