Man made (synthetic) corticosteriods are used to treat a large number of conditions and symptoms. Corticosteriods are used as a replacement therapy when the body is not naturally producing enough of its own of natural corticosteriods. They are also used to treat conditions where there is inflammation, autoimmune conditions or allergy symptoms. Corticosteriod can be taken orally as a systemic treatment to treat the body as a whole or it can be applied to the affected area for a local effect as creams, inhalations, nasal sprays, eye drops, ear drops or injections. Examples of conditions they treat are allergies, asthma, COPD, dermatitis, ulcerative colitis, Crohn’s disease, multiple sclerosis, nephrotic syndrome, adrenal insufficiency, inflammation, Addison’s disease, rheumatic conditions such as arthritis, fibromyalgia and lupus.
The human genome includes approximately 20,000 protein coding genes and 70% of these genes are expressed in the normal, adult adrenal glands.   Only some 250 genes are more specifically expressed in the adrenal glands compared to other organs and tissues. The adrenal gland specific genes with highest level of expression include members of the cytochrome P450 superfamily of enzymes. Corresponding proteins are expressed in the different compartments of the adrenal gland, such as CYP11A1 , HSD3B2 and FDX1 involved in steroid hormone synthesis and expressed in cortical cell layers, and PNMT and DBH involved in noradrenalin and adrenalin synthesis and expressed in the medulla.