Anabolic steroids, known technically as anabolic-androgen steroids or colloquially as "steroids" (or even "roids"), are drugs that mimic the effects of testosterone and dihydrotestosterone in the body. They increase protein synthesis within cells, which results in the buildup of cellular tissue (anabolism), especially in muscles. Anabolic steroids also have androgenic and masculinity-enhancing properties, including the development and maintenance of masculine characteristics such as the growth of the vocal cords, testicles and body hair (secondary sexual characteristics). Anabolic-androgenic steroids were first isolated, identified and synthesized in the 1930's, and are now used therapeutically in medicine to induce bone growth, stimulate appetite, induce male puberty and treat chronic wasting conditions, such as cancer and AIDS. Anabolic steroids also increase muscle mass and physical strength, and are therefore used by athletes and bodybuilders alike to enhance strength or physique. Known side effects include harmful changes in cholesterol levels (increased Low density lipoprotein and decreased High density lipoprotein), acne, high blood pressure and liver damage. Some of these effects can be mitigated by taking supplemental drugs.
Mechanism of action
The pharmacodynamics of anabolic steroids are unlike peptide hormones. Water-soluble peptide hormones cannot penetrate the fatty cell membrane, and only indirectly affect the nucleus of target cells through their interaction with the cell’s surface receptors. However, as fat-soluble hormones, anabolic steroids are membrane-permeable, and influence the nucleus of cells by direct action. The pharmacodynamic action of anabolic steroids begins when the exogenous hormone penetrates the membrane of the target cell and binds to an androgen receptor located in the cytoplasm of that cell. From there, the compound hormone-receptor diffuses into the nucleus, where it either alters the expression of genes or activates processes that send signals to other parts of the cell. Different types of anabolic steroids bind to the androgen receptor with different affinities, depending on their chemical structure. Some anabolic steroids such as methandrostenolone bind weakly to this receptor in vitro, but still exhibit androgenic effects in vivo. The reason for this discrepancy is not known. The effect of anabolic steroids on muscle mass is caused in at least two ways: first, they increase the production of proteins; second, they reduce recovery time by blocking the effects of the stress hormone cortisol on muscle tissue, so that catabolism of muscle is greatly reduced. Some hypothesize that this reduction in muscle breakdown may occur by way of anabolic steroids inhibiting the action of other steroid hormones called glucocorticoids, which promote the breakdown of muscles. Anabolic steroids also affect the number of cells that develop into fat-storage cells by instead favoring cellular differentiation into muscle cells. Additionally, anabolic steroids can decrease fat by increasing basal metabolic rate (BMR), since an increase in muscle mass increases BMR.
Physical effects
Anabolic steroids are testosterone and dihydrotestosterone hormone mimics that stimulate anabolism, specifically protein synthesis and muscle hypertrophy. Due to its similarity to the male sex hormones, using anabolic steroids can result in masculinization of women and changes to secondary sex characteristics of men. This makes steroids attractive to those wishing to alter their appearance, particularly for body building. Further negative side effects of anabolic steroids include stunted growth in adolescents, increase in cholesterol levels, high blood pressure, acne, liver damage and changes to the left ventricle of the heart, not to mention potential psychiatric issues. Despite these side effects, anabolic steroids can be used therapeutically to stimulate bone growth and appetite, and treat chronic wasting conditions associated with cancer and AIDS, though at much lower dosages than those used for performance enhancement.
Steroid abuse
Abuse of anabolic steroids differs from the abuse of other illicit substances, because the initial use of anabolic steroids is motivated not by the immediate euphoria that accompanies other abused drugs such as cocaine, heroin and marijuana, but by the user's desire to change their appearance and performance, characteristics of great importance to adolescents. These effects can boost confidence and strength, leading the user to overlook the potential serious long-term damage that these substances can cause. Due to the unfair advantage given to athletes and competitors who use anabolic steroids, all major sports associations have banned their use.
While anabolic steroids can enhance certain types of performance or appearance, they are dangerous drugs, and when used inappropriately, they can cause a host of severe, long-lasting and often irreversible negative health consequences. For example, they can stunt the height of growing adolescents, masculinize women and alter sex characteristics of men. Anabolic steroids can also lead to premature heart attacks, strokes, liver tumors, kidney failure and serious psychiatric problems. In addition, because steroids are often injected, users risk contracting or transmitting HIV or hepatitis.
Mechanism of action
The pharmacodynamics of anabolic steroids are unlike peptide hormones. Water-soluble peptide hormones cannot penetrate the fatty cell membrane, and only indirectly affect the nucleus of target cells through their interaction with the cell’s surface receptors. However, as fat-soluble hormones, anabolic steroids are membrane-permeable, and influence the nucleus of cells by direct action. The pharmacodynamic action of anabolic steroids begins when the exogenous hormone penetrates the membrane of the target cell and binds to an androgen receptor located in the cytoplasm of that cell. From there, the compound hormone-receptor diffuses into the nucleus, where it either alters the expression of genes or activates processes that send signals to other parts of the cell. Different types of anabolic steroids bind to the androgen receptor with different affinities, depending on their chemical structure. Some anabolic steroids such as methandrostenolone bind weakly to this receptor in vitro, but still exhibit androgenic effects in vivo. The reason for this discrepancy is not known. The effect of anabolic steroids on muscle mass is caused in at least two ways: first, they increase the production of proteins; second, they reduce recovery time by blocking the effects of the stress hormone cortisol on muscle tissue, so that catabolism of muscle is greatly reduced. Some hypothesize that this reduction in muscle breakdown may occur by way of anabolic steroids inhibiting the action of other steroid hormones called glucocorticoids, which promote the breakdown of muscles. Anabolic steroids also affect the number of cells that develop into fat-storage cells by instead favoring cellular differentiation into muscle cells. Additionally, anabolic steroids can decrease fat by increasing basal metabolic rate (BMR), since an increase in muscle mass increases BMR.
Physical effects
Anabolic steroids are testosterone and dihydrotestosterone hormone mimics that stimulate anabolism, specifically protein synthesis and muscle hypertrophy. Due to its similarity to the male sex hormones, using anabolic steroids can result in masculinization of women and changes to secondary sex characteristics of men. This makes steroids attractive to those wishing to alter their appearance, particularly for body building. Further negative side effects of anabolic steroids include stunted growth in adolescents, increase in cholesterol levels, high blood pressure, acne, liver damage and changes to the left ventricle of the heart, not to mention potential psychiatric issues. Despite these side effects, anabolic steroids can be used therapeutically to stimulate bone growth and appetite, and treat chronic wasting conditions associated with cancer and AIDS, though at much lower dosages than those used for performance enhancement.
Steroid abuse
Abuse of anabolic steroids differs from the abuse of other illicit substances, because the initial use of anabolic steroids is motivated not by the immediate euphoria that accompanies other abused drugs such as cocaine, heroin and marijuana, but by the user's desire to change their appearance and performance, characteristics of great importance to adolescents. These effects can boost confidence and strength, leading the user to overlook the potential serious long-term damage that these substances can cause. Due to the unfair advantage given to athletes and competitors who use anabolic steroids, all major sports associations have banned their use.
While anabolic steroids can enhance certain types of performance or appearance, they are dangerous drugs, and when used inappropriately, they can cause a host of severe, long-lasting and often irreversible negative health consequences. For example, they can stunt the height of growing adolescents, masculinize women and alter sex characteristics of men. Anabolic steroids can also lead to premature heart attacks, strokes, liver tumors, kidney failure and serious psychiatric problems. In addition, because steroids are often injected, users risk contracting or transmitting HIV or hepatitis.
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