Liver collagen

Schuppan, D. Structure of the extracellular matrix in normal and fibrotic liver collagens and glycoproteins. Semin. Liver Dis. 1990 10 1-10... 

Chojkier, M., Houglum, K., Lee, K. S.. and Buck, M. (1998) Long- and short-term D-alpha-tocopherol supplementation inhibits liver collagen alpha 1(1) gene expression. Am J Phvsiol 275, G1480-5. 

M.p. 190-192 C. The enolic form of 3-oxo-L-gulofuranolactone. It can be prepared by synthesis from glucose, or extracted from plant sources such as rose hips, blackcurrants or citrus fruits. Easily oxidized. It is essential for the formation of collagen and intercellular material, bone and teeth, and for the healing of wounds. It is used in the treatment of scurvy. Man is one of the few mammals unable to manufacture ascorbic acid in his liver. Used as a photographic developing agent in alkaline solution. 

A complete physical examination and laboratory analysis are needed to rule out secondary causes and to assess kyphosis and back pain. Laboratory testing may include complete blood count, liver function tests, creatinine, urea nitrogen, calcium, phosphorus, alkaline phosphatase, albumin, thyroid-stimulating hormone, free testosterone, 25-hydroxyvitamin D, and 24-hour urine concentrations of calcium and phosphorus. Urine or serum biomarkers (e.g., cross-linked N-telopeptides of type 1 collagen, osteocalcin) are sometimes used. 

Most of the triacylglycerol is stored in adipose tissue depots. Smaller amounts are found in muscle and liver. Adipose tissue is connective tissue that contains adipocytes, blood vessels, collagen and lymphocytes. The last latter are present in lymph nodes, most of which are present within adipose tissue depots throughout the body. Indeed, there may be more lymphocytes in adipose... 

Protein turnover in an adult is about 4 to 5 g per kg body wt, equivalent to about 250 to 350 g of protein hydrolysed and resynthesised every day in the tissues of an adult human. This represents considerably more protein than is ingested in food. The rates of protein turnover vary enormously, depending on the nature of the protein, the condition of the subject and the tissue (Table 8.3). Proteins (mainly enzymes) in the liver are replaced every few hours or days whereas structural proteins (e.g. collagen, contractile proteins) are stable for several months. Contractile proteins can be degraded relatively rapidly in some conditions (see below). 

When the receptor binding domain is encoded in a small peptide sequence, the peptide hg-and can also be synthesized and conjugated chemically to the carrier protein. This approach was followed in our laboratory by Beljaars et al. for the development of carriers aimed at the hepatic stellate cell, a cell type involved in liver fibrosis [33] (see also Chapter 4). A peptide sequence derived from the receptor binding domains of collagen VI was incorporated into a cyclic peptide homing device, and subsequently conjugated to lysine residues of HSA. This carrier bound selectively to activated hepatic stellate cells and rapidly accumulated in the livers of fibrotic rats. 

Influence of acute carbon tetrachloride exposure on transcription of liver-specific versus general cellular genes relationship between chronic carbon tetrachloride exposure and collagen synthesis and hepatic fi brosi s. 

Ala-Kokko L, Stenback F, Ryhanen L. 1987. Preventive effect of malotilate on carbon tetrachloride-induced liver damage and collagen accumulation in the rat. Biochem J 246 503-509. 

Ascorbic acid or vitamin C is found in fruits, especially citrus fruits, and in fresh vegetables. Man is one of the few mammals unable to manufacture vitamin C in the liver. It is essential for the formation of collagen as it is a cofactor for the conversion of proline and lysine residues to hydroxyproline and hydroxylysine. It is also a cofactor for carnitine synthesis, for the conversion of folic acid to folinic acid and for the hydroxylation of dopamine to form norepinephrine. Being a lactone with two hydroxyl groups which can be oxidized to two keto groups forming dehydroascorbic acid, ascorbic acid is also an anti-oxidant. By reducing ferric iron to the ferrous state in the stomach, ascorbic acid promotes iron absorption. 

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