Cardiovascular disease deficiency effect

GH synthesis and secretion does not disappear when linear growth is complete. In fact isolation of hGH from cadaver pituitary glands would not have been possible if it did. Physicians caring for adult patients with pituitary disease began to realize that even with optimum replacement of other hormones, patients who acquired GH deficiency in adulthood complained bitterly about diminished quality of life. Studies from Europe also documented increased cardiovascular morbidity and mortality in these patients [13], Because it was no longer necessary to conserve scarce supplies of hGH for use in children, physicians were able to study GH effects in adults with growth hormone deficiency. These studies have shown that GH improves body composition (decreases fat mass and increases lean body mass) and decreases risk factors for cardiovascular disease [14]. 

NO also reduces endothelial adhesion of monocytes and leukocytes, key features of the early development of atheromatous plaques. This effect is due to the inhibitory effect of NO on the expression of adhesion molecules on the endothelial surface. In addition, NO may act as an antioxidant, blocking the oxidation of low-density lipoproteins and thus preventing or reducing the formation of foam cells in the vascular wall. Plaque formation is also affected by NO-dependent reduction in endothelial cell permeability to lipoproteins. The importance of eNOS in cardiovascular disease is supported by experiments showing increased atherosclerosis in animals deficient in eNOS by pharmacologic inhibition. Atherosclerosis risk factors, such as smoking, hyperlipidemia, diabetes, and hypertension, are associated with decreased endothelial NO production, and thus enhance atherogenesis. 

Niacin deficiency leads to unwanted multisystemic problems that are often associated with dermatological changes. Pellagra is a condition in which niacin deficiency causes a symmetrical pigmented rash, thickened skin and superficial scaling which are found in sun-exposed body areas. The classic triad of niacin deficiency are the three D s—dermatitis, diarrhoea and dementia (Hegyi et al. 2004). Some of the effects on the central nervous system include depression, anxiety, restlessness and poor concentration. In addition, alcoholic individuals with poor nutrition can develop pellagroid encephalopathy (Cook et al. 1998). The role of niadn deficiency in cardiovascular disease and lipid metabolism remains to be fully explored. 

Niacin is a water-soluble vitamin that has been available as a lipid-lowering medication and in prevention of atherosclerosis for half a century (Ganji et al. 2003 Olsson 2010). Numerous studies have documented its beneficial effects on reducing cardiovascular disease (CVD) (Olsson 2010). Clinically, the most well-known effect of niacin deficiency is pellagra which, as noted above, is manifested by dermatitis, diarrhoea and dementia (Bodor and Offermanns 2008 Ganji, et al. 2003). In this chapter we look at the effects of niacin on human physiology and its consequent effects on disease states. 

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