Oxidative enzyme activity, growth

Thyroid hormones affect a wide variety of peripheral tissues throughout the individual s life.8,55 In some situations, these hormones exert a direct effect on cellular function (e.g., T4 and T3 appear to increase cellular metabolism by directly increasing oxidative enzyme activity). In other instances, thyroid hormones appear to play a permissive role in facilitating the function of other hormones. For instance, thyroid hormones must be present for growth hormone to function properly. The principal effects of the thyroid hormones are listed below. 

Table IV. Effect of Oxidative Enzyme Activity on the Growth of...

Phenolic compounds naturally occurring in plants have induced many physiological responses that duplicate those reported for ozone and/or peroxyacetylnitrate (PAN). Chlorogenic acid is a competitive inhibitor of lAA-oxidase (35) and plant growth is adversely affected by increased concentrations of auxins (36). Concentrations of chlorogenic acid are increased in tobacco tissue exposed to ozone ( ) Phenols inhibit ATP synthesis (37), oxidative phosphorylation ( ) and SH enzyme activity (27) they increase respiration (38), reduce CO2 fixation (22), modify both membrane permeability (40) and oxidation rate of reduced NADH... 

Sodium chloride content is closely related to ham quality, not only because of its direct effect on taste but also because of its effect on flavour development (75). The influence of sodium chloride content on volatile compound generation could be related to its effect on lipid-oxidation reactions, enzyme activity and microbial growth. As expected, salt content affected significantly a number of compounds described previously as dry-cured odorants (Figure 1) seven aldehydes and two acids. 

TTA induces peroxisomal and mitochondrial P-oxidation enzymes in addition to several other enzymes in lipid metabolism. Furthermore, TTA functions as a ligand for PPAR-a and PPAR-y and it stimulates both peroxisomal and mitochondrial proliferation. An increasing amount of genes that are known to carry PPAR response elements (PPREs) is reported, and differential regulation by these receptors is likely to affect the growth potential. The result of TTA treatment is a reorganization of the cellular lipid metabolism towards an increased metabolic activity. 

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