The androgens

While these steroids can be extracted directly from human tissue, in most instances they can also be synthesized chemically. Direct chemical synthesis methodology has also facilitated the development of synthetic steroid analogues. Many such analogues exhibit therapeutic advantages over the native hormone, e.g. they may be more potent, be absorbed intact from the digestive tract, or exhibit a longer duration of action in the body. The majority of sex steroid hormones now used clinically are chemically synthesized. 

Testosterone is transported in the blood bound to transport proteins, the most important of which are albumin (a non-specific carrier) and testosterone-oestradiol binding globulin (TEBG), a 40kDa polypeptide which binds testosterone and oestrogens with high affinity. 

Testosterone and other androgens induce their characteristic biological effects via binding to a specific intracellular receptor. These hormones promote  

Androgens are used medically as replacement therapy in male hypogonadal disorders (i.e. impaired functioning of the testes). They are administered to adolescent males displaying delayed puberty to promote an increase in the size of the scrotum and other sexual organs. Androgens are also sometimes administered to females, particularly in the management of some 

Danazol Synthetic androgen. Suppresses gonadotrophin production. Exhibits some weak androgenic activity Oral administration in the treatment of endometriosis, benign breast disorders, menorrhagia, premenstrual syndrome and hereditary angioedema 

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The mechanism by which TBT causes these effects has been extensively stiidied. The androgenic effects of TBT appear to be caused by interference with steroid biosynthesis rather than by mimicking the action of testosterone at the androgen receptor. Exposure of female molluscs to TBT leads to an elevation in testosterone in the haemolymph. " Much of the experimental evidence... 

In the case of androgens as with estrogens there is occasionally need for treatment of patients with chronic sustained doses of these drugs. Resort is made to esters of the androgen with long-chain fatty acids in order to provide oil-soluble agents ... 

Halogenation of steroid 3-ketones can lead to complicated mixtures by virtue of the fact that the kinetic enol leads to 3 halo products, whereas the thermodynamic product is that halogenated at the 4 position. Carefully controlled reaction of the 5a-androstanolone with chlorine thus leads to the 2a-chloro derivative (29). Reaction of that intermediate with O(p-nitrophenyl)-hydroxylamine affords the androgenic agent ni stremine acetate (30). ... 

Hormone antagonists (tamoxifen and toremifen bind to the estradiol receptor, flutamide binds to the androgen receptor) are used for treating breast and prostate cancer. 

Sex steroid receptors are members of the steroid hormone receptor (SHR) family that ligand-dependently regulate functions of the sexual organs. Sex steroid receptors are the androgen receptor [1] (AR), the estrogen receptor a [2] and (3 [3] (ERa, ER 3), and the progesterone receptor [4] (PR). 

Aromatase inhibitors that inhibit the androgen aromatization in estrogens and thus block estrogen synthesis. 

The anabolic steroids are synthetic dragp chemically related to the androgens. Like the androgens, they promote tissue-building processes. Given in normal doses,... 

Virilization in the woman is the most common reaction associated with anabolic steroids, especially when higher doses are used. Acne occurs frequently in all age groups and both sexes. Nausea, vomiting, diarrhea, fluid and electrolyte imbalances (the same as for the androgens, discussed previously), testicular atrophy,... 

Older adults with cardiac problems or kidney disease are at increased risk for sodium and water retention when taking the androgens or anabolic steroids. 

P. acnes is an anaerobic diphteroid that populates the androgen-stimulated sebaceous follicles and is a normal constituent of the cutaneous microflora even if acne is not infectious, the commensal P. acnes acts in acne pathogenesis. Three pieces of evidence support the role of P. acnes in acne 1) higher counts of P. acnes in individuals with acne than in those without acne 2) correlation between the reduction of P. acnes counts and the clinical improvement of the disease and 3) correlation between development of acne and presence of antibiotic-resistant P. acnes organisms. P. acnes products mediate the formation of comedones and contribute to their rupture, leading to extrusion of... 

Cyproterone acetate (CPA) is a progestational antiandrogen that blocks the androgen receptors. It is combined with ethinyl estradiol in an oral contraceptive formulation, which is indicated in female acne patients with a high level of seborrhea, therapy resistant papulo-pustular acne or acne conglobata not responding to other treatments. 

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