Corticosteroids naturally occurring

Cholesterol (Section 26 11) The most abundant steroid in am mals and the biological precursor to other naturally occur ring steroids including the bile acids sex hormones and corticosteroids... 

The metabolism of the naturally occurring adrenal steroids has been discussed above. The synthetic corticosteroids (Table 39-1) are in most cases rapidly and completely absorbed when given by mouth. Although they are transported and metabolized in a fashion similar to that of the endogenous steroids, important differences exist. 

However, corticosteroids and their metabolites (1) were early recognized as possessing powerful antiinflammatory and immunomodulatory properties. Even prior to 1950, reports of the antiarthritic properties of cortisone (1) by Hench and co-workers (2) indicated the potential for these compounds to reduce the suffering of patients with inflammatory diseases. This awareness, combined with the first synthesis of naturally occurring glucocorticoids (11-desoxycorticosterone), led not only to the massive increase in research in the area of steroid synthesis and physiology, but to a Nobel prize in 1950 for early steroid pioneers Hench, Reichstein, and Kendall. 

Corlan hydrocortisone, corticoliberin corticotrophin-releasing factor, corticorelin corticotrophin-releasing factor. CORTICOSTEROIDS as a family are natural steroid hormones secreted by the adrenal cortex, or are synthetic substances that closely resemble them. There are two main types GLUCOCORTICOIDS (corticosterone. cortisone and hydrocortisone) are essential for utilization of carbohydrate, fat and protein in the body, and in the normal response to stress. Naturally occurring and synthetic glucocorticoids have a powerful antiinflammatory effect. 

Glucocorticoids also have antiallergic properties, as a result of and by an inhibition of the synthesis of histamine by mast cells and basophils. Of the naturally occurring corticosteroids, only cortisol and corticosterone possess glucocorticoid activity, with cortisol the most effective. Cortisone and 11-dehydrocorticosterone lack direct glucocorticoid activity, but have potential glucocorticoid activity because they can be metabolixed to cortisol and corticosterone, respectively. 

Systemic corticosteroids can increase the loss of potassium, particularly those that are naturally occurring (cortisone, deoxycortone, hydrocortisone) whereas the synthetic derivatives (betamethasone, dexametha-sone, methylprednisolone, prednisolone, prednisone, triamcinolone) have much less mineralocorticoid activity. There is therefore the possibility of potassium depletion, particularly when corticosteroids are used long-term, which may increase the risk of digitalis toxicity. These corticosteroids also cause sodium and water retention, resulting in oedema and hypertension, which can lead to cardiac failure in some individuals. 

The greatest potassium loss occurs with the naturally occurring corticosteroids such as cortisone and hydrocortisone. Corticotropin (ACTH), which is a pituitary hormone, and tetracosactrin (a synthetic polypeptide) stimulate corticosteroid secretion by the adrenal cortex and can thereby indirectly cause potassium loss. Fludrocortisone also causes potassium loss. The synthetic corticosteroids (glucocorticoids) have a less marked potassium-depleting effect and are therefore less likely to cause problems. These include betamethasone, dexamethasone, prednisolone, prednisone and triamcinolone. 

XI. Syntheses of Related Corticosteroids Although not intended to be complete, this section includes the synthesis of most of the naturally occurring C2i06 corticosteroids. 

It is important to remember that adverse effects of topical corticosteroids may be systemic in nature and hypothalamic-pituitary-adrenal axis suppression can occur, especially when high-potency corticosteroids are used. Infants and small children may be more susceptible due to their increased skin sur-face body mass ratio.18 Topical corticosteroids may also cause striae, skin atrophy, acne, telangiectasias, and rosacea.2,10,18 Atrophy can result in thin, fragile, easily lacerated skin. Striae are caused by tearing of dermal connective tissue and are irreversible.18 Due to their significant adverse-effect profile, it has been recommended that no topical corticosteroid be used regularly for more than 4 weeks without review and reassessment.2... 

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