Human shoulder tendon biopsy samples in organ culture produce procollagenase and tissue inhibitor of metalloproteinases.
Journal - Annals of the rheumatic diseases (ENGLAND )
OBJECTIVE--To investigate the production of the matrix metalloproteinase (MMP), collagenase (MMP-1), and its natural inhibitor, the tissue inhibitor of metalloproteinases (TIMP) by diseased human tendon samples in organ culture. METHODS--Portions of tendons were excised from the shoulders of patients undergoing shoulder surgery, classified as either proximal to the lesion (abnormal) or distal to the lesion (normal) according to their macroscopic appearance at surgery, and placed in organ culture for periods of up to 28 days. The release of collagenase and TIMP activity in the conditioned culture medium was measured. RESULTS--Procollagenase and TIMP were both produced by all the tendon samples for an extended period of time. The levels of enzyme and inhibitor varied between patients, but in most of them TIMP levels were greater than collagenase levels. In one sample of calcified tendon, procollagenase levels were greater than those of TIMP. The mean level of collagenase produced by tendon proximal to the lesion and tendon distal to the lesion were not significantly different (95.2 (SD 106.8) U/g and 34.0 (45.3) U/g, respectively), while the corresponding figures for TIMP were 109.7 (62.3) U/g and 53.0 (27.9) U/g (p = < 0.05), although there was considerable variation in some samples. Western blotting and collagen fragment analysis confirmed that the collagenolytic activity detected was attributable to the metalloproteinase fibroblast collagenase (MMP-1). CONCLUSIONS--Tendon tissue can actively secrete procollagenase, an enzyme that, once activated, is capable of remodelling collagen, the major connective tissue component of tendon. Collagenase is produced even in unstimulated cultures, although the concentrations of TIMP are usually greater than that of collagenase in most samples. Some activation of collagenase appeared to have occurred. These results indicate that tendon tissue cells are capable of producing a remodelling response, even in end stage tendon disease.
|ISSN : ||0003-4967|
|Mesh Heading : ||Adult Aged Blotting, Western Chronic Disease Collagenases Culture Techniques Enzyme Precursors Female Glycoproteins Humans Male Middle Aged Muscular Diseases Rotator Cuff Shoulder Joint Tissue Inhibitor of Metalloproteinases enzymology|
|Mesh Heading Relevant : ||biosynthesis biosynthesis biosynthesis enzymology enzymology|
The conservative management of rotator cuff disorders.
Journal - British journal of rheumatology (ENGLAND )
A process of progressive tendon failure leads to rotator cuff rupture in a significant percentage of the ageing population but many individuals remain asymptomatic. Aetiological factors are varied and not completely understood but greater knowledge of shoulder function and mechanics allows for improved non-operative and operative management. There is a definite role for comprehensive conservative treatment of rotator cuff disorders in those cases where surgery is not clearly indicated. Successful rehabilitation depends largely on proper clinical assessment and individualized treatment. This requires a good understanding of the biomechanics of shoulder, and especially rotator cuff, function. Few recent studies have properly evaluated the results of such non-operative treatment.
|ISSN : ||0263-7103|
|Mesh Heading : ||Biomechanics Humans Muscular Diseases Rotator Cuff pathology physiopathology therapy pathology|
|Mesh Heading Relevant : ||physiopathology|
Overuse injuries in adolescent athletes.
Journal - Sports medicine (Auckland, N.Z.) (NEW ZEALAND )
As sports participation increases so too does the incidence of injuries, both acute and overuse. The growing skeleton is particularly susceptible due to the presence of growth cartilage at 3 locations; the epiphyseal plate, the joint surface and the apophysis. The risk of injury is most pronounced during the rapid growth spurt of adolescence when other factors, such as muscle tightness across joints, also become important in the aetiology of sporting injury. Overuse injuries seen in this age group may reflect the growth characteristics of the immature skeleton or may be of the type seen in adult athletes undergoing rigorous training schedules. Recent developments in organised competitive sport have seen growing individuals undertake prolonged and intensive training programmes when they are particularly at risk of sustaining an overuse injury. The training programme is one of a number of risk factors important in the generation of injury, many of which can be modified or controlled to an extent. Other factors such as growth deformities or malalignments are peculiar to the individual and preparticipation evaluation of the young athlete helps to identify those at risk. Whilst long term disability rarely eventuates, the loss of enjoyment and temporary incapacity resulting from this type of injury is significant. It is apparent that many of these injuries are preventable, and given the information available concerning the factors involved in their aetiology, it is the responsibility of coaches and health professionals alike to become involved in their early diagnosis, treatment and prevention.
|ISSN : ||0112-1642|
|Mesh Heading : ||Adolescent Athletic Injuries Cumulative Trauma Disorders Female Humans Male Physical Education and Training Risk Factors epidemiology prevention & control epidemiology prevention & control|
|Mesh Heading Relevant : ||etiology etiology|