{"id":23062,"date":"2022-07-23T11:42:12","date_gmt":"2022-07-23T05:57:12","guid":{"rendered":"https:\/\/www.revoscience.com\/en\/?p=23062"},"modified":"2022-07-23T11:42:15","modified_gmt":"2022-07-23T05:57:15","slug":"researchers-discover-hibernation-power-in-bear-blood-what-next","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/researchers-discover-hibernation-power-in-bear-blood-what-next\/","title":{"rendered":"Researchers Discover Hibernation Power in Bear Blood: What Next?"},"content":{"rendered":"\n

Japanese scientists have observed \u201cmuscle gain\u201d in cultured human skeletal muscle cells infused with serum from hibernating black bears, confirming that unique factors activated in these creatures\u2019 blood during winter trigger their remarkable ability to prevent muscular atrophy despite months of inactivity.<\/p>\n\n\n\n

But what these key blood components remain unknown.<\/p>\n\n\n\n

Hibernating bears can lie still for 5-7 months a year inside their dens without eating or drinking. In humans, just three weeks of inactivity is enough to lose muscle mass. Prolong it and it could lead to sedentary lifestyle-related diseases like obesity and diabetes \u2014 and even early death. Bears, however, survive their hibernation with limited muscle loss, minimal metabolic dysfunction, and unharmed physical functions.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

\u201cThe \u2018use it or lose it\u2019 phenomenon is a well-accepted physiological principle for the skeletal muscle, which is highly plastic in response to functional demands. Disuse typically leads to skeletal muscle loss and metabolic dysfunction in many animal species, including humans,\u201d study first-author Mitsunori Miyazaki<\/a>, associate professor at Hiroshima University\u2019s Graduate School of Biomedical and Health Sciences<\/a>, explained.<\/p>\n\n\n\n

\u201cIn contrast, hibernating animals are likely better described to be under the \u2018no use, but no lose\u2019 phenomenon, in that there is potential resistance to muscle atrophy during continued disuse conditions.\u201d<\/p>\n\n\n\n

The study<\/a> jointly conducted with researchers from Hokkaido University found that the serum drawn from the blood of hibernating Japanese black bears weakened the \u201cdestruction mechanism\u201d controlling muscular degradation. Their findings were published in the journal PLOS ONE.<\/p>\n\n\n\n

Muscle mass is generally determined by the dynamic balance between the \u201csynthesis\u201d and \u201cdegradation\u201d of proteins. But since this balance is altered by the hibernating bears\u2019 serum, the cultured muscle cells showed significant protein content growth following 24 hours of treatment. This notable increase in protein was not seen in cultured muscle cells infused with serum collected during the bears\u2019 active summer season.<\/p>\n\n\n\n

The researchers attributed the diminished capacity of the muscles\u2019 \u201cdestruction mechanism\u201d to the suppressed expression of MuRF1 (Muscle RING-finger protein-1), the switch triggering the shredding of unused muscles. According to them, it is likely that suppression of MuRF1 expression was mediated by the activation of the Akt\/FOXO3a (protein kinase B\/Forkhead box class O 3a) axis responsible for the elevation of protein synthesis.<\/p>\n\n\n\n

They also observed increased levels of the growth factor hormone IGF-1 (insulin-like growth factor-1) in the hibernating bear serum. The researchers identified it as a candidate upstream factor that induces activation of the Akt\/FOXO3a axis. Previous studies have reported seasonal variations of IGF-1 concentrations in bear serum. These studies found IGF-1 concentrations were highest during the active summer period and lowest in early hibernation and then increased again near the end of hibernation.<\/p>\n\n\n\n

But Miyazaki and his co-researchers later redirected their attention elsewhere after correcting their calculations on IGF-1 concentration levels in the hibernating bear serum. They said it is a possibility that the higher IGF-1 concentrations observed in the study were simply due to a decrease in the serum\u2019s water content brought about by other causes, such as dehydration.  <\/p>\n\n\n\n

\u201cWe have indicated that \u2018some factor\u2019 present in hibernating bear serum may regulate protein metabolism in cultured human skeletal muscle cells and contribute to the maintenance of muscle mass. However, the identification of this \u2018factor\u2019 has not yet been achieved,\u201d Miyazaki said.<\/p>\n\n\n\n

Originally a physical therapist, the associate professor said he wondered why it is not possible to build muscles that do not weaken in the first place rather than restore deteriorated muscles. <\/p>\n\n\n\n

\u201cI wanted to do research that would lead to the development of effective rehabilitation and training methods,\u201d Miyazaki said, adding that this is the reason he got interested in exploring hibernation\u2019s secrets.<\/p>\n\n\n\n

\u201cBy identifying this \u2018factor\u2019 in hibernating bear serum and clarifying the unexplored mechanism behind \u2018muscles that do not weaken even without use\u2019 in hibernating animals, it is possible to develop effective rehabilitation strategies in humans and prevent becoming bedridden in the future.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"

Japanese scientists have observed \u201cmuscle gain\u201d in cultured human skeletal muscle cells infused with serum from hibernating black bears,<\/p>\n","protected":false},"author":2,"featured_media":23063,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17,138],"tags":[],"class_list":["post-23062","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research","category-wildlife"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",1100,825,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear-200x200.png",200,200,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear-533x400.png",533,400,true],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear-768x576.png",750,563,true],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear-675x506.png",675,506,true],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",1100,825,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",1100,825,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",1067,800,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",760,570,false],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",600,450,false],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",600,450,false],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear-760x490.png",760,490,true],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear-550x360.png",550,360,true],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear-95x65.png",95,65,true],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",640,480,false],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",96,72,false],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2022\/07\/hibernation-study-Japanese-black-bear.png",150,113,false]},"author_info":{"info":["RevoScience"]},"category_info":"Research<\/a> Wildlife<\/a>","tag_info":"Wildlife","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/23062","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=23062"}],"version-history":[{"count":0,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/23062\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/23063"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=23062"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=23062"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=23062"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}