{"title":"mTOR 信号的减少导致初级纤毛的丧失,这与髁状突软骨与年龄相关的退化有关。","authors":"Megumi Kitami, Masaru Kaku, Lay Thant, Takeyasu Maeda","doi":"10.1007/s11357-024-01143-x","DOIUrl":null,"url":null,"abstract":"<p><p>Age-related deterioration of condylar cartilage is an etiological factor in temporomandibular joint-osteoarthritis (TMJ-OA). However, its underlying mechanism remains unknown. Therefore, we examined age-related changes and the relationship between mTOR signaling and primary cilia in condylar cartilage to determine the intrinsic mechanisms of age-related TMJ-OA. Age-related morphological changes were analyzed using micro-computed tomography and safranin O-stained histological samples of the mandibular condyle of C57BL/6J mice (up to 78 weeks old). Immunohistochemistry was used to assess the activity of mTOR signaling, primary cilia frequency, and Golgi size of condylar chondrocytes. Four-week-old mice receiving an 11-week series of intraperitoneal injections of rapamycin, a potent mTOR signaling inhibitor, were used for the histological evaluation of the condylar cartilage. The condylar cartilage demonstrated an age-related reduction in cartilage area, including chondrocyte size, cell density, and cell size distribution. The Golgi size, primary cilia frequency, and mTOR signaling also decreased with age. Rapamycin injections resulted in both diminished cartilage area and cell size, resembling the phenotypes observed in aged mice. Rapamycin-injected mice also exhibited a smaller Golgi size and lower primary cilia frequency in condylar cartilage. We demonstrated that a loss of primary cilia due to a decline in mTOR signaling was correlated with age-related deteriorations in condylar cartilage. Our findings provide new insights into the tissue homeostasis of condylar cartilage, contributing to understanding the etiology of age-related TMJ-OA.</p>","PeriodicalId":12730,"journal":{"name":"GeroScience","volume":" ","pages":"5995-6007"},"PeriodicalIF":5.3000,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11493995/pdf/","citationCount":"0","resultStr":"{\"title\":\"A loss of primary cilia by a reduction in mTOR signaling correlates with age-related deteriorations in condylar cartilage.\",\"authors\":\"Megumi Kitami, Masaru Kaku, Lay Thant, Takeyasu Maeda\",\"doi\":\"10.1007/s11357-024-01143-x\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Age-related deterioration of condylar cartilage is an etiological factor in temporomandibular joint-osteoarthritis (TMJ-OA). However, its underlying mechanism remains unknown. Therefore, we examined age-related changes and the relationship between mTOR signaling and primary cilia in condylar cartilage to determine the intrinsic mechanisms of age-related TMJ-OA. Age-related morphological changes were analyzed using micro-computed tomography and safranin O-stained histological samples of the mandibular condyle of C57BL/6J mice (up to 78 weeks old). Immunohistochemistry was used to assess the activity of mTOR signaling, primary cilia frequency, and Golgi size of condylar chondrocytes. Four-week-old mice receiving an 11-week series of intraperitoneal injections of rapamycin, a potent mTOR signaling inhibitor, were used for the histological evaluation of the condylar cartilage. The condylar cartilage demonstrated an age-related reduction in cartilage area, including chondrocyte size, cell density, and cell size distribution. The Golgi size, primary cilia frequency, and mTOR signaling also decreased with age. Rapamycin injections resulted in both diminished cartilage area and cell size, resembling the phenotypes observed in aged mice. Rapamycin-injected mice also exhibited a smaller Golgi size and lower primary cilia frequency in condylar cartilage. We demonstrated that a loss of primary cilia due to a decline in mTOR signaling was correlated with age-related deteriorations in condylar cartilage. Our findings provide new insights into the tissue homeostasis of condylar cartilage, contributing to understanding the etiology of age-related TMJ-OA.</p>\",\"PeriodicalId\":12730,\"journal\":{\"name\":\"GeroScience\",\"volume\":\" \",\"pages\":\"5995-6007\"},\"PeriodicalIF\":5.3000,\"publicationDate\":\"2024-12-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11493995/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"GeroScience\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1007/s11357-024-01143-x\",\"RegionNum\":2,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2024/3/25 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q1\",\"JCRName\":\"GERIATRICS & GERONTOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"GeroScience","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1007/s11357-024-01143-x","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/3/25 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"GERIATRICS & GERONTOLOGY","Score":null,"Total":0}
A loss of primary cilia by a reduction in mTOR signaling correlates with age-related deteriorations in condylar cartilage.
Age-related deterioration of condylar cartilage is an etiological factor in temporomandibular joint-osteoarthritis (TMJ-OA). However, its underlying mechanism remains unknown. Therefore, we examined age-related changes and the relationship between mTOR signaling and primary cilia in condylar cartilage to determine the intrinsic mechanisms of age-related TMJ-OA. Age-related morphological changes were analyzed using micro-computed tomography and safranin O-stained histological samples of the mandibular condyle of C57BL/6J mice (up to 78 weeks old). Immunohistochemistry was used to assess the activity of mTOR signaling, primary cilia frequency, and Golgi size of condylar chondrocytes. Four-week-old mice receiving an 11-week series of intraperitoneal injections of rapamycin, a potent mTOR signaling inhibitor, were used for the histological evaluation of the condylar cartilage. The condylar cartilage demonstrated an age-related reduction in cartilage area, including chondrocyte size, cell density, and cell size distribution. The Golgi size, primary cilia frequency, and mTOR signaling also decreased with age. Rapamycin injections resulted in both diminished cartilage area and cell size, resembling the phenotypes observed in aged mice. Rapamycin-injected mice also exhibited a smaller Golgi size and lower primary cilia frequency in condylar cartilage. We demonstrated that a loss of primary cilia due to a decline in mTOR signaling was correlated with age-related deteriorations in condylar cartilage. Our findings provide new insights into the tissue homeostasis of condylar cartilage, contributing to understanding the etiology of age-related TMJ-OA.
GeroScienceMedicine-Complementary and Alternative Medicine
CiteScore
10.50
自引率
5.40%
发文量
182
期刊介绍:
GeroScience is a bi-monthly, international, peer-reviewed journal that publishes articles related to research in the biology of aging and research on biomedical applications that impact aging. The scope of articles to be considered include evolutionary biology, biophysics, genetics, genomics, proteomics, molecular biology, cell biology, biochemistry, endocrinology, immunology, physiology, pharmacology, neuroscience, and psychology.