Anonymous
Not logged in
Talk
Contributions
Create account
Log in
Search
Editing
Collagen
(section)
From MEpedia, a crowd-sourced encyclopedia of ME and CFS science and history
Namespaces
Page
Discussion
More
More
Page actions
Read
Edit
Edit source
History
Warning:
You are not logged in. Your IP address will be publicly visible if you make any edits. If you
log in
or
create an account
, your edits will be attributed to your username, along with other benefits.
Anti-spam check. Do
not
fill this in!
== Collagen-degrading factors == === Pathogens === Infection can degrade collagen via direct secretion<ref name=":1">{{Cite journal | last = Harrington | first = DJ | date = Jun 1996 | title = Bacterial collagenases and collagen-degrading enzymes and their potential role in human disease. | url = https://www.ncbi.nlm.nih.gov/pmc/articles/PMC174012/ | journal = Infection and Immunity|volume=64 | issue = 6 | pages = 1885–1891|issn=0019-9567|pmid=8675283}}</ref> of collagenases and other [[Enzyme|enzymes]] (in the case of [[bacteria]]) or increased host production of [[Matrix metalloproteinase|matrix metalloproteinases]] (MMPs) as part of the normal [[immune system|immune response]] (in the case of bacteria and [[Virus|viruses]]). Numerous bacteria secrete their own [[collagenase]]s.<ref name=":1" /><ref>{{Cite journal | last = Duarte | first = Ana Sofia | last2 = Correia | first2 = Antonio | last3 = Esteves | first3 = Ana Cristina | date = 2016 | title = Bacterial collagenases - A review | url =https://www.ncbi.nlm.nih.gov/pubmed/24754251 | journal = Critical Reviews in Microbiology|volume=42 | issue = 1 | pages = 106–126 |doi=10.3109/1040841X.2014.904270|issn=1549-7828|pmid=24754251}}</ref> [[Borrelia]] spirochetes upregulate production of human collagenase (MMP-1) and gelatinase B (MMP-9)<ref>{{Cite journal | last = Gebbia | first = Joseph A. | last2 = Coleman | first2 = James L. | last3 = Benach | first3 = Jorge L. | date = 2001-01-01 | title = Borrelia Spirochetes Upregulate Release and Activation of Matrix Metalloproteinase Gelatinase B (MMP-9) and Collagenase 1 (MMP-1) in Human Cells |url =https://iai.asm.org/content/69/1/456 | journal = Infection and Immunity|language=en|volume=69 | issue = 1 | pages = 456–462|doi=10.1128/IAI.69.1.456-462.2001|issn=0019-9567|pmid=11119537}}</ref>, an enzyme that can degrade both [[elastin]] and partially hydrolyzed collagen.<ref name="Baker2009">{{Cite book | title = Comprehensive Vascular and Endovascular Surgery | date = 2009 | url=https://www.sciencedirect.com/science/article/pii/B9780323057264000299 | pages = 465–472 | last = Baxter | first = B. Timothy | author-link= | last2 = MacTaggart | first2 = Jason | author-link2 = |isbn=978-0-323-05726-4|chapter=Pathogenesis of Aortic Aneurysms|language=en|edition=2nd|location=Philadelphia|publisher=Mosby|editor-last=Hallett|editor-first=John W.|editor2-last=Mills|editor2-first=Joseph L.|editor3-last=Earnshaw|editor3-first=Jonothan J.|editor4-last=Reekers|editor4-first=Jim A.|editor5-last=Rooke|editor5-first=Thom W.|doi=10.1016/b978-0-323-05726-4.00029-9|pmc=|pmid=|access-date=|quote=|via=}}</ref> Borrelia infection has been associated with damage to collagen and elastin fibres, causing "spontaneous ruptures of tendons after slight strain, dislocation of vertebrae and an accumulation of prolapsed intervertebral discs as well as ossification of tendon insertions."<ref>{{Cite journal | last = Müller | first = Kurt E | date = 2012-12-31 | title = Damage of Collagen and Elastic Fibres by Borrelia Burgdorferi – Known and New Clinical and Histopathological Aspects |url =https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3751012/ | journal = The Open Neurology Journal|volume=6 | pages = 179–186|doi=10.2174/1874205X01206010179|issn=1874-205X|pmc=3751012|pmid=23986790}}</ref> MMP-8 and MMP-9 are upregulated in bacterial [[meningitis]] and the latter is associated with an increased risk of [[blood-brain barrier]] breakdown and neurological sequale such as [[epilepsy]] and [[cognitive dysfunction]].<ref>{{Cite journal | last = Tiveron | first = Marcos Gradim | last2 = Pomerantzeff | first2 = Pablo Maria Alberto | last3 = de Lourdes Higuchi | first3 = Maria | last4 = Reis | first4 = Marcia Martins | last5 = de Jesus Pereira | first5 = Jaqueline | last6 = Kawakami | first6 = Joyce Tieko | last7 = Ikegami | first7 = Renata Nishiyama | last8 = de Almeida Brandao | first8 = Carlos Manuel | last9 = Jatene | first9 = Fabio Biscegli | date = 2017-04-21 | title = Infectious agents is a risk factor for myxomatous mitral valve degeneration: A case control study | url = https://www.ncbi.nlm.nih.gov/pubmed/28431520 | journal = BMC infectious diseases|volume=17 | issue = 1 | pages = 297|doi=10.1186/s12879-017-2387-8|issn=1471-2334|pmc=5399830|pmid=28431520}}</ref> [[Herpes simplex virus]]<ref name=":2">{{Cite journal | date = 2006-12-13 | title = Herpes-simplex virus encephalitis is characterized by an early MMP-9 increase and collagen type IV degradation | url =https://www.sciencedirect.com/science/article/pii/S0006899306029246 | journal = Brain Research|language=en|volume=1125 | issue = 1 | pages = 155–162|doi=10.1016/j.brainres.2006.09.093|issn=0006-8993}}</ref>, [[Human herpesvirus 6|HHV-6]]<ref>{{Cite journal | date = 2014-11-01 | title = Serum levels of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinases-1 in human herpesvirus-6–infected infants with or without febrile seizures |url =https://www.sciencedirect.com/science/article/pii/S1341321X14002682 | journal = Journal of Infection and Chemotherapy|language=en|volume=20 | issue = 11 | pages = 716–721|doi=10.1016/j.jiac.2014.07.017|issn=1341-321X}}</ref> and [[Coxsackie B]]<ref>{{Cite journal | last = De Palma | first = Armando M. | last2 = Verbeken | first2 = Erik | last3 = Van Aelst | first3 = Ilse | last4 = Van den Steen | first4 = Philippe E. | last5 = Opdenakker | first5 = Ghislain | last6 = Neyts | first6 = Johan | date = 2008-12-05 | title = Increased gelatinase B/matrix metalloproteinase 9 (MMP-9) activity in a murine model of acute coxsackievirus B4-induced pancreatitis |url =https://www.ncbi.nlm.nih.gov/pubmed/18929380 | journal = Virology|volume=382 | issue = 1 | pages = 20–27|doi=10.1016/j.virol.2008.08.046|issn=1096-0341|pmid=18929380}}</ref><ref>{{Cite journal | date = 2006-03-01 | title = Matrix metalloproteinases and tissue inhibitors of metalloproteinases in coxsackievirus-induced myocarditis |url =https://www.sciencedirect.com/science/article/pii/S1054880705001729 | journal = Cardiovascular Pathology|language=en|volume=15 | issue = 2 | pages = 63–74|doi=10.1016/j.carpath.2005.11.008|issn=1054-8807}}</ref> infection result in increased production of MMP-9, which is associated with Type IV and Type V collagen degradation.<ref name=":2" /><ref>{{Cite journal | last = Zeng|first = Z.S. | last2 = Cohen | first2 = A.M. | last3 = Guillem | first3 = J.G. | date = May 1999 | title = Loss of basement membrane type IV collagen is associated with increased expression of metalloproteinases 2 and 9 (MMP-2 and MMP-9) during human colorectal tumorigenesis |url =https://www.ncbi.nlm.nih.gov/pubmed/10334190 | journal = Carcinogenesis|volume=20 | issue = 5 | pages = 749–755|issn=0143-3334|pmid=10334190}}</ref><ref>{{Cite journal | last = Van den Steen | first = Philippe E. | last2 = Dubois | first2 = Bénédicte | last3 = Nelissen | first3 = Inge | last4 = Rudd | first4 = Pauline M. | last5 = Dwek | first5 = Raymond A. | last6 = Opdenakker | first6 = Ghislain | date = Jan 2002 | title = Biochemistry and Molecular Biology of Gelatinase B or Matrix Metalloproteinase-9 (MMP-9) | url = https://www.tandfonline.com/doi/abs/10.1080/10409230290771546 | journal = Critical Reviews in Biochemistry and Molecular Biology|language=en|volume=37 | issue = 6 | pages = 375–536|doi=10.1080/10409230290771546|issn=1040-9238}}</ref> Coxsackie B infection induces immune cells to secrete MMP-2, MMP-3, MMP-8, MMP-9 and MMP-12.<ref>{{Cite journal | last = Cheung|first = Caroline | last2 = Luo | first2 = Honglin | last3 = Yanagawa | first3 = Bobby | last4 = Leong | first4 = Hon Sing | last5 = Samarasekera | first5 = Dinesh | last6 = Lai | first6 = John C.K. | last7 = Suarez | first7 = Agripina | last8 = Zhang | first8 = Jingchun | last9 = McManus | first9 = Bruce M. | date = Mar 2006 | title = Matrix metalloproteinases and tissue inhibitors of metalloproteinases in coxsackievirus-induced myocarditis |url =https://www.ncbi.nlm.nih.gov/pubmed/16533694 | journal = Cardiovascular Pathology: The Official Journal of the Society for Cardiovascular Pathology|volume=15 | issue = 2 | pages = 63–74|doi=10.1016/j.carpath.2005.11.008|issn=1054-8807|pmid=16533694}}</ref><ref>{{Cite journal | last = Meng|first = Xiao-hui | last2 = Wang | first2 = Yi | last3 = Zhuang | first3 = Jian-xin | last4 = Han | first4 = Xiu-zhen | last5 = Chen | first5 = Yao | last6 = Jin | first6 = You-peng | last7 = Wang | first7 = Yu-lin | last8 = Yu | first8 = Yong-hui | last9 = Spires | first9 = James P. | date = Aug 2004 | title = Dynamic changes in myocardial matrix metalloproteinase activity in mice with viral myocarditis |url =https://www.ncbi.nlm.nih.gov/pubmed/15361294 | journal = Chinese Medical Journal|volume=117 | issue = 8 | pages = 1195–1199|issn=0366-6999|pmid=15361294}}</ref><ref>{{Cite journal | last = Rutschow|first = Susanne | last2 = Leschka | first2 = Sebastian | last3 = Westermann | first3 = Dirk | last4 = Puhl | first4 = Kerstin | last5 = Weitz | first5 = Anneke | last6 = Ladyszenskij | first6 = Leonid | last7 = Jaeger | first7 = Sebastian | last8 = Zeichhardt | first8 = Heinz | last9 = Noutsias | first9 = Michel | date = 2010-03-25 | title = Left ventricular enlargement in coxsackievirus-B3 induced chronic myocarditis--ongoing inflammation and an imbalance of the matrix degrading system | url = https://www.ncbi.nlm.nih.gov/pubmed/20035743 | journal = European Journal of Pharmacology|volume=630 | issue = 1-3 | pages = 145–151|doi=10.1016/j.ejphar.2009.12.019|issn=1879-0712|pmid=20035743}}</ref> ==== Infection and Ehlers-Danlos Syndromes ==== [[Ehlers-Danlos syndrome|Ehlers-Danlos Syndromes]] are a group connective tissue disorders caused by genetic defects in the production of collagen. Type III, [[hypermobile EDS]] (hEDS), is also thought to be genetic but as a genetic marker has not yet been identified; it is diagnosed via signs and symptoms. A 2018 case study of a patient who met the diagnostic criteria for hEDS and had a chronic Bartonella infection found their hEDS symptoms resolved with antibiotic treatment for Bartonella.<ref name=":0">{{Cite journal | last = Mozayeni|first = Bobak Robert | last2 = Maggi | first2 = Ricardo Guillermo | last3 = Bradley | first3 = Julie Meredith | last4 = Breitschwerdt | first4 = Edward Bealmear | date = Apr 2018 | title = Rheumatological presentation of Bartonella koehlerae and Bartonella henselae bacteremias |url =https://journals.lww.com/md-journal/Pages/articleviewer.aspx?year=2018&issue=04270&article=00032&type=Fulltext | journal = Medicine|language=en-US|volume=97 | issue = 17| pages = e0465|doi=10.1097/MD.0000000000010465|issn=0025-7974}}</ref> [[Mycoplasma pneumoniae]] has been associated with mitral valve degeneration, a complication of EDS.<ref>{{Cite journal | last = Tiveron | first = Marcos Gradim | last2 = Pomerantzeff | first2 = Pablo Maria Alberto | last3 = de Lourdes Higuchi | first3 = Maria | last4 = Reis | first4 = Marcia Martins | last5 = de Jesus Pereira | first5 = Jaqueline | last6 = Kawakami | first6 = Joyce Tieko | last7 = Ikegami | first7 = Renata Nishiyama | last8 = de Almeida Brandao | first8 = Carlos Manuel | last9 = Jatene | first9 = Fabio Biscegli | date = 2017-04-21 | title = Infectious agents is a risk factor for myxomatous mitral valve degeneration: A case control study | url = https://www.ncbi.nlm.nih.gov/pubmed/28431520 | journal = BMC infectious diseases|volume=17 | issue = 1 | pages = 297|doi=10.1186/s12879-017-2387-8|issn=1471-2334|pmc=5399830|pmid=28431520}}</ref> === Fluoroquinolone antibiotics === “Fluoroquinolones upregulate cell matrix metalloproteinases, resulting in a reduction of collagen fibrils of types I and III collagen.”<ref>{{Cite web | url = https://www.jwatch.org/na48248/2019/02/13/adverse-effects-fluoroquinolones-where-do-we-stand | title = NEJM Journal Watch: Summaries of and commentary on original medical and scientific articles from key medical journals | website = jwatch.org|access-date=2019-06-18}}</ref> A longitudinal study found Fluoroquinolones increased the risk of collagen-related adverse events like tendon ruptured and detached retinas.<ref>{{Cite journal | last = Redelmeier | first = Donald A. | last2 = Lu | first2 = Hong | last3 = Daneman | first3 = Nick | date = 2015-11-01 | title = Fluoroquinolones and collagen associated severe adverse events: a longitudinal cohort study | url = https://bmjopen.bmj.com/content/5/11/e010077 | journal = BMJ Open|language=en|volume=5 | issue = 11| pages = e010077|doi=10.1136/bmjopen-2015-010077|issn=2044-6055|pmid=26582407}}</ref> In December 2018, the FDA recommended against its use in patients with connective tissue disorders like [[Ehlers-Danlos Syndrome]] and Marfan Syndrome.<ref>{{Cite journal | last = Research|first = Center for Drug Evaluation and | date = 2019-04-15 | title = FDA warns about increased risk of ruptures or tears in the aorta blood vessel with fluoroquinolone antibiotics in certain patients |url =http://www.fda.gov/drugs/drug-safety-and-availability/fda-warns-about-increased-risk-ruptures-or-tears-aorta-blood-vessel-fluoroquinolone-antibiotics | journal = FDA|language=en}}</ref> [[Doxycycline]], by contrast, inhibits MMP production.<ref name=":02">{{Cite journal | last = De Paiva | first = Cintia S. | last2 = Corrales | first2 = Rosa M. | last3 = Villarreal | first3 = Arturo L. | last4 = Farley | first4 = William J. | last5 = Li | first5 = De-Quan | last6 = Stern | first6 = Michael E. | last7 = Pflugfelder | first7 = Stephen C. | date = 2006-09-01 | title = Corticosteroid and doxycycline suppress MMP-9 and inflammatory cytokine expression, MAPK activation in the corneal epithelium in experimental dry eye | url =http://www.sciencedirect.com/science/article/pii/S0014483506001709 | journal = Experimental Eye Research|volume=83 | issue = 3 | pages = 526–535|doi=10.1016/j.exer.2006.02.004|issn=0014-4835}}</ref><ref>{{Cite journal | last = Roach|first = D. M | last2 = Fitridge | first2 = R. A | last3 = Laws | first3 = P. E | last4 = Millard | first4 = S. H | last5 = Varelias | first5 = A | last6 = Cowled | first6 = P. A | date = 2002-03-01 | title = Up-regulation of MMP-2 and MMP-9 Leads to Degradation of Type IV Collagen During Skeletal Muscle Reperfusion Injury; Protection by the MMP Inhibitor, Doxycycline | url =http://www.sciencedirect.com/science/article/pii/S1078588402915984 | journal = European Journal of Vascular and Endovascular Surgery|volume=23 | issue = 3 | pages = 260–269|doi=10.1053/ejvs.2002.1598|issn=1078-5884}}</ref><ref>{{Cite journal | last = Niedzwiecki|first = A. | last2 = Rath | first2 = M. | last3 = Kalinovsky | first3 = T. | last4 = Monterrey | first4 = J.C. | last5 = Roomi | first5 = M.W. | date = 2010-03-01 | title = In vitro modulation of MMP-2 and MMP-9 in human cervical and ovarian cancer cell lines by cytokines, inducers and inhibitors |url =http://www.spandidos-publications.com/or/23/3/605/abstract | journal = Oncology Reports|volume=23 | issue = 3 | pages = 605–614|doi=10.3892/or_00000675|issn=1021-335X}}</ref><ref>{{Cite journal | last = Choi|first = Dong-Hoon | last2 = Moon | first2 = Ik-Sang | last3 = Choi | first3 = Bong-Kyu | last4 = Paik | first4 = Jeong-Won | last5 = Kim | first5 = Yoon-Sik | last6 = Choi | first6 = Seong-Ho | last7 = Kim | first7 = Chong-Kwan | date = 2004 | title = Effects of sub-antimicrobial dose doxycycline therapy on crevicular fluid MMP-8, and gingival tissue MMP-9, TIMP-1 and IL-6 levels in chronic periodontitis |url =https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1600-0765.2004.00696.x | journal = Journal of Periodontal Research|language=en|volume=39 | issue = 1 | pages = 20–26|doi=10.1111/j.1600-0765.2004.00696.x|issn=1600-0765}}</ref><ref>{{Cite journal | last = Li|first = De-Quan | last2 = Lokeshwar | first2 = Balakrishna L | last3 = Solomon | first3 = Abraham | last4 = Monroy | first4 = Dagoberto | last5 = Ji | first5 = Zhonghua | last6 = Pflugfelder | first6 = Stephen C | date = 2001-10-01 | title = Regulation of MMP-9 Production by Human Corneal Epithelial Cells |url =http://www.sciencedirect.com/science/article/pii/S0014483501910541 | journal = Experimental Eye Research|volume=73 | issue = 4 | pages = 449–459|doi=10.1006/exer.2001.1054|issn=0014-4835}}</ref><ref>{{Cite journal | last = Brown David L. | last2 = Desai Kavita K. | last3 = Vakili Babak A. | last4 = Nouneh Chadi | last5 = Lee Hsi-Ming | last6 = Golub Lorne M. | date = 2004-04-01 | title = Clinical and Biochemical Results of the Metalloproteinase Inhibition with Subantimicrobial Doses of Doxycycline to Prevent Acute Coronary Syndromes (MIDAS) Pilot Trial | url = https://www.ahajournals.org/doi/full/10.1161/01.ATV.0000121571.78696.dc | journal = Arteriosclerosis, Thrombosis, and Vascular Biology|volume=24 | issue = 4 | pages = 733–738|doi=10.1161/01.ATV.0000121571.78696.dc}}</ref> === Mold === ''[[Stachybotrys chartarum]]'' (black [[mold]]) release proteinases that can hydrolyze gelatin and collagen I and IV.<ref>{{Cite journal | last = Yike | first = Iwona | last2 = Rand | first2 = Thomas | last3 = Dearborn | first3 = Dorr G. | date = 2007-07-03 | title = The role of fungal proteinases in pathophysiology of Stachybotrys chartarum | url = https://doi.org/10.1007/s11046-007-9037-4 | journal = Mycopathologia|language=en|volume=164 | issue = 4 | pages = 171|doi=10.1007/s11046-007-9037-4|issn=1573-0832}}</ref> Three Mycotoxins, deoxynivalenol (DON), nivalenol (NIV) and T-2 toxin, were study in an the context of an experimental cartilage model. They were found to increase the expression of MMPs and result in the loss of [[aggrecan]] and type II collagen. Selenium partially inhibited the effects of these mycotoxins.<ref>{{Cite journal | last = Caterson | first = Bruce | last2 = Li | first2 = Jin | last3 = Wang | first3 = Jiali | last4 = Luo | first4 = Mingxiu | last5 = Liu | first5 = Jiayuan | last6 = Zhang | first6 = Zengtie | last7 = Fu | first7 = Qiang | last8 = Chen | first8 = Jinghong | last9 = Li | first9 = Siyuan | date = 2012 | title = The Effects of Mycotoxins and Selenium Deficiency on Tissue-Engineered Cartilage | url =https://www.karger.com/Article/FullText/335046 | journal = Cells Tissues Organs|language=en|volume=196 | issue = 3 | pages = 241–250|doi=10.1159/000335046|issn=1422-6405|pmid=22538829}}</ref> === Sex hormones === Several animal studies of collagen in muscle and the aorta have found that [[estrogen]] decreases and [[testosterone]] increases collagen and elastin.<ref>{{Cite journal | last = Fischer | first = G.M. | last2 = Swain | first2 = M.L. | date = 1977-06-01 | title = Effect of sex hormones on blood pressure and vascular connective tissue in castrated and noncastrated male rats |url =https://www.physiology.org/doi/abs/10.1152/ajpheart.1977.232.6.H617 | journal = American Journal of Physiology-Heart and Circulatory Physiology|volume=232 | issue = 6| pages=H617–H621|doi=10.1152/ajpheart.1977.232.6.H617|issn=0363-6135}}</ref><ref>{{Cite journal | last = Cembrano|first = JosÉ | last2 = Lillo | first2 = Manuel | last3 = Val | first3 = JosÉ | last4 = Mardones | first4 = Jorge | date = 1960-05-01 | title = Influence of Sex Difference and Hormones on Elastine and Collagen in the Aorta of Chickens |url =http://insights.ovid.com/ | journal = Circulation Research|language=ENGLISH|volume=8 | issue = 3 | pages = 527–529|issn=0009-7330|pmid=13808759}}</ref><ref>{{Cite journal | last = Fischer | first = Grace M. | last2 = Swain | first2 = Margaret L. | date = 1980-08-01 | title = Influence of contraceptive and other sex steroids on aortic collagen and elastin | url =http://www.sciencedirect.com/science/article/pii/0014480080900039 | journal = Experimental and Molecular Pathology|volume=33 | issue = 1 | pages = 15–24|doi=10.1016/0014-4800(80)90003-9|issn=0014-4800}}</ref><ref>{{Cite journal | last = Fischer | first = G.M. | last2 = Swain | first2 = M.L. | date = 1985-02-01 | title = Effects of estradiol and progesterone on the increased synthesis of collagen in atherosclerotic rabbit aortas |url =http://www.sciencedirect.com/science/article/pii/0021915085901777 | journal = Atherosclerosis|volume=54 | issue = 2 | pages = 177–185|doi=10.1016/0021-9150(85)90177-7|issn=0021-9150}}</ref><ref>{{Cite journal | last = Fischer | first = Grace M. | date = 1972-11-01 | title = In Vivo EflEects of Estradiol on Collagen and Elastin Dynamics in Rat Aorta | url = https://academic.oup.com/endo/article/91/5/1227/2621144 | journal = Endocrinology|language=en|volume=91 | issue = 5 | pages = 1227–1232|doi=10.1210/endo-91-5-1227|issn=0013-7227}}</ref> A study of collagen in male cattle found that collagen synthesis increased with puberty, possibly as a result of testosterone.<ref>{{Cite journal | last = Cross | first = H.R. | last2 = Schanbacher | first2 = B.D. | last3 = Crouse | first3 = J.D. | date = 1984-01-01 | title = Sex, age and breed related changes in bovine testosterone and intramuscular collagen | url =http://www.sciencedirect.com/science/article/pii/0309174084900214 | journal = Meat Science|volume=10 | issue = 3 | pages = 187–195|doi=10.1016/0309-1740(84)90021-4|issn=0309-1740}}</ref> Another, that intramuscular collagen was higher in bulls than in steers (castrated cattle).<ref>{{Cite journal | last = Judge | first = M.D. | last2 = Diekman | first2 = M.A. | last3 = Lemenager | first3 = R.P. | last4 = Aberle | first4 = E.D. | last5 = Jones | first5 = S.J. | last6 = Gerrard | first6 = D.E. | date = 1987-11-01 | title = Collagen Stability, Testosterone Secretion and Meat Tenderness in Growing Bulls and Steers |url =https://academic.oup.com/jas/article/65/5/1236/4662470 | journal = Journal of Animal Science|language=en|volume=65 | issue = 5 | pages = 1236–1242|doi=10.2527/jas1987.6551236x|issn=0021-8812}}</ref> An ''in vitro'' study of rat cartilage cells found that testosterone stimulated collagen synthesis, but only in male cells.<ref>{{Cite journal | last = Boyan | first = B.D. | last2 = Soskolne | first2 = W.A. | last3 = Brooks | first3 = B.P. | last4 = Ornoy | first4 = A. | last5 = Nasatzky | first5 = E. | last6 = Schwartz | first6 = Z. | date = 1994-04-01 | title = Gender-specific, maturation-dependent effects of testosterone on chondrocytes in culture | url =https://academic.oup.com/endo/article/134/4/1640/3035468 | journal = Endocrinology|language=en|volume=134 | issue = 4 | pages = 1640–1647|doi=10.1210/endo.134.4.8137726|issn=0013-7227}}</ref>
Summary:
Please make sure your edits are consistent with
MEpedia's guidelines
.
By saving changes, you agree to the
Terms of use
, and you irrevocably agree to release your contribution under the
CC BY-SA 3.0 License
and the
GFDL
. You agree that a hyperlink or URL is sufficient attribution under the Creative Commons license.
Cancel
Editing help
(opens in new window)
This page is a member of 3 hidden categories:
Category:All articles with unsourced statements
Category:Articles with unsourced statements from unknown year
Category:CS1 日本語-language sources (ja)
Navigation
Navigation
Skip to content
Main page
Browse
Become an editor
Random page
Popular pages
Abbreviations
Glossary
About MEpedia
Links for editors
Contents
Guidelines
Recent changes
Pages in need
Search
Help
Wiki tools
Wiki tools
Special pages
Page tools
Page tools
User page tools
More
What links here
Related changes
Page information
Page logs