Collagen connective tissue disorders

Defects in collagen synthesis, structure, or assembly Into fibers are the principal basis for a group of connective tissue disorders called Ehlers-Danlos syndrome (EDS). 

Persikov, A. V., Pillitteri, R. J., Amin, P., Schwarze, U., Byers, P. H., and Brodsky, B. (2004). Stability related bias in residues replacing glycines within the collagen triple helix (Gly-Xaa-Yaa) in inherited connective tissue disorders. Hum. Mut. 24, 330-337. 

CONNECTIVE TISSUE DISORDERS (COLLAGEN VASCULAR DISEASES) ... 

Other mutations of fibrillar collagen, or mutations that affect collagen-processing, cause Ehlers-Danlos syndrome (EDS), a group of heritable connective tissue disorders causing skin hyperextensibility, articular hypermobility, and tissue fragility. The 3 major types are classic (EDS-I and EDS-II), hypermobility (EDS-III) and vascular (EDS-IV). 

Since all copper-dependent enzymes and metabolism are affected, biosynthesis of elastin and collagen is defective. Menkes victims usually die before 3 years of age, frequently from neurodegenerative defects or connective tissue disorders (Danks 1989). Identification of the Menkes gene or the Wilson s gene will not provide a cure. However, as with other hereditary diseases, early diagnosis gives promise for a major reduction in the frequencies of these diseases. 

Yet another connective tissue disorder which may result from a collagen abnormality is osteogenesis imperfecta where there is disruption of the normal collagen-apatite relationship. Among its most frequent manifestations are brittle bones, deafness, a thin skin, loose-jointedness and hernia. The teeth often have an abnormal coloration and, although the enamel is essentially normal, the dentine is defective and soft, and the root canals and pulp chambers tend to become obliterated. 

Kielty, C.M., Hopkinson, 1., Grant, M.E. Collagen structure, assembly and organization in the extracellular matrix. In Connective Tissue and its Heritable Disorders Wiley-Liss, Chichester, pp. 103-147, 1993. 

Collagen-vascular disorders Giant cell arteritis, lupus erythematosus, mixed connective tissue syndromes, polymyositis, polymyalgia rheumatica, rheumatoid arthritis, temporal arteritis... 

Kielty, C. M., and Grant, M. E. (2002). The Collagen Family Structure Assembly and Organization in the Extracellular Matrix. In Connective Tissue and its Heritable Disorders, (P. M. Royce andB. Steinmann, Eds.), pp. 159-222. Wiley-Liss, New York. 

Pulmonary fibrosis is the medical term given to an end-stage restrictive lung disorder characterized by excessive deposition of connective tissue (predominantly collagen) in the lung interstitium. This deposition is caused by some type of acute or subacute injury to the lung that triggers inflam-... 

Medical concern with collagen is derived from its importance as a constituent of tissues intimately involved in aspects of the aging process, in neoplastic growth, in diseases connected with vitamin deficiencies or hormonal imbalances, and, indeed, in many general systemic disorders involving the connective tissues in a diffuse or inflammatory way (124). 

Osteogenesis imperfecta (01) is an inherited disorder of connective tissue resulting from abnormal quantity and/or quality of type I collagen, the major protein of bone. The phenotypic presentation is enormously varied, ranging from perinatal death to normal lifespan complicated by only a few fractures. Because fractures are a feature of the condition it must be given serious consideration in any child with unexplained fractures. There are four major types in the Sillence classification (Sillence et al. 1979), but it should be noted that there are no strict boundaries. Type IV is an uncommon type of 01 (only 5% of the patients in the Sillence study) with mild to severe bone disease. Patients with this type... 

Alterations of the connective tissue composition of the extracellular matrix are an important feature of various inherited and acquired disorders of soft tissue (Miller 1976). This phenomenon is particularly important in the lung in which elasticity is a vital determinant of function. Interstitial collagen is composed of at least two distinct trimeric polypeptide molecules designated as type 1 and type 111 collagens. Type 1 contains two ai(I) chains and one 02 chain, whereas type 111 contains 3 identical a, (HI) chains. Pulmonary fibroblasts produce more type I... 

Autoimmune disorders are characterized by the breakdown of various connective tissues (the collagen diseeises), such as lupus erythematosus, polyarteritis nodosa, rheumatoid arthritis, and rheumatic fever. Also, it is suspected that autoimmune reactions may be responsible in part for certain abnormalities associated with (1) diabetes, when there heis been an unexplainable deterioration of the cells of the pancreas that secrete insulin (2) insufficient secretion of adrenal cortical hormones (Addison s diseeise) due to weisting of the glandular tissue (3) lack of stomach acid (achlorhydria) and/or lack of intrinsic factor resulting in pernicious anemia, because antibodies have attacked the cells of the stomach which secrete the deficient substances and (4) ulcerative colitis, when the lesions are much more severe than might be expected under the circumstances. 

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