Connective tissue breakdown

L. Wright, and A. Churg. Acute cigarette smoke-induced connective tissue breakdown is mediated by neutrophils and prevented by alphal-antitrypsin. Am J Respir Cell Mol Biol 2000 22(2) 244-252. 

Cawston, T.E. (1996) Metalloproteinase inhibitors and the prevention of connective tissue breakdown. Pharmacol. Then. 70.163-182. 

Golub LM, Lee HM, Ryan ME, et al. Tetracyclines inhibit connective tissue breakdown by multiple non-antimicrobial mechanisms. Adv Dent... 

Assisting in breakdown of connective tissue and muscle fibers within ingested food... 

Conversely, the connective tissues and cartilage are much more resistant to proteolysis and will survive for a longer period of time, although they too will eventually succumb to the effects of putrefaction. Reticulin, epidermis, and muscle protein will resist breakdown for some time, whereas collagen and keratin may survive for longer periods (Linch and Prahlow 2001). Keratin is an insoluble fibrous protein found in the skin, hair, and nails, and its resistance to attack by most proteolytic enzymes (Gupta and Ramnani 2006) is the reason it is often found intact amongst skeletal remains, particularly in burial environments (Macko et al. 1999). 

The immune system is a complex network of checks and balances designed to discriminate self from nonself (foreign) tissues. It helps rid the body of infectious agents, tumor cells, and products associated with the breakdown of cells. In rheumatoid arthritis this system no longer can differentiate self from nonself tissues and attacks the synovial tissue and other connective tissues. 

Morphologically, emphysema is associated with a destruction of the alveolar septum, which results in a dilation and consequent enlargement of the alveolar spaces (Fig. 19). This is apparently caused by a breakdown of the interstitial connective tissue proteins (primarily elastin) that provide the major structural framework of the lung parenchyma. Two types of emphysema have been defined on the basis of the types of destruction of the alveolar septa observed and the type of dilation of the terminal respiratory unit (the acini) that is observed. A typical acinus branches from a terminal bronchiole and consists of the respiratory bronchioles that have alveolated walls and lead to the alveolar ducts and ultimately to the alveolar sacs (see Fig. 3). In centrilobular (or centriacinar) emphysema, the sites of degradation and dilation are limited to the region of the terminal and respiratory bronchioles. In panlobular (or panacinar) emphysema, the entire acinus (including the alveolar ducts and sacs) is more uniformly affected. 

Cortisol is an important hormone with effects on many tissues in the body. It plays a major role in metabolism by promoting protein breakdown in muscle and connective tissue and the release of glycerol and free fatty acids from adipose (issue. Thus, cortisol provides... 

Enzymes have also been used in the preparation of protein ingredients from animal wastes. Mohr (1980) described the use of proteolytic enzymes in the preparation of protein concentrates from fish offal. Fish protein waste was ground with protease and incubated to yield a concentrated fish protein, which was then dried. Generally, the contractile and connective tissue proteins are hydrolysed most efficiently. Sarcoplasmic proteins tend to aggregate and resist enzyme attack. The proteins are broken down into peptides and individual amino acids, and the longer the hydrolysis continues the higher the yield of hydrolysates but the greater the peptide breakdown. For many food applications peptide breakdown needs to be carefully controlled. 

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