Collagen abnormalities

A number of rare genetic diseases involve collagen abnormalities, including Marfan s syndrome and the Ehlers-Danlos syndromes, which result in hyperextensible joints and skin. The formation of atheroselerotie plaques, which cause arterial blockages in advanced stages, is due in part to the abnormal formation of collagenous structures in blood vessels. 

LH3 null mice are embryonic lethal at E9.5-14.5, show fragmentation of basement membrane and possibly some type IV collagen abnormalities... 

Collagen abnormalities, such as Ehlers-Damlos syndrome. Marfan s syndrome, pseudoxanthoma elasticum. and osteogenesis imperfecta... 

Coronary dissection (Figures 8.39-8.41) This is an ACS that occurs suddenly, usually in young multiparous women, during the postpartum period, and is due to a collagen abnormality that favours dissection. The LAD is the most frequently involved artery and it may be dissected from its origin, which commonly causes a quite large infarction. It is even more severe because it occurs in an area with no previous ischaemia and in which collateral circulation has not been developed. 

Hydroxyprolinemia hydroxyprolinuria, mental retardation, no obvious skeletal or collagen abnormality... 

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. 

Aminopropionitrile (present in sweet peas) covalently inactivates lysyl oxidase, preventing intramolecular cross-linking of collagen and causing abnormalities in joints, bones, and blood vessels. 

A Number of Genetic Diseases Result From Abnormalities in the Synthesis of Collagen... 

McLennan, S., Yue, D.K., Fisher, E., Capogreco, C., HefFernan, S., Ross, G.R. and Turtle, J.R, (1988). Deficiency of ascorbic acid in experimental diabetes relationship with collagen and polyol pathway abnormalities. Diabetes 37, 359-361. 

Endocrine abnormalities Hypothyroidism Adrenal insufficiency Pituitary insufficiency Chronic renal disease Chronic inflammatory disease Granulomatous diseases Collagen vascular diseases Hepatic disease... 

Genetically determined abnormalities in GAG or collagen synthesis lead to joints becoming easily dislocated, hyperextendable and hyperelastic ( double-jointed ),... 

P3h1 mice do not die prematurely but have abnormal collagen fibril morphology in tendon, decreased bone density, and abnormalities in skin and developing limbs lethal at El 1.5 basement membrane is not formed well by electron microscopy... 

Col Hal null mice have fibril diameter abnormalities in the early postnatal stage but the adult showed no significant differences. Type XIV collagen might function early in development regulating the entry of fibril intermediates into lateral fibril growth. ... 

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