Dihydroandrostenedione (Androstanedione) is a steroid metabolite and a precursor of both testosterone and estrone normally produced by the adrenal gland and gonads and is converted to testosterone through the action of 17β-hydroxysteroid dehydrogenase, which is found in most body tissues. Androstenedione is also produced by some plants and has recently been marketed as a product for increasing blood testosterone concentrations to be used as a natural alternative to anabolic steroid use. However, androstenedione administration during resistance training did not significantly alter the serum testosterone concentration in normotestosterogenic young men. The increased muscle size and strength observed with resistance training were also not augmented with androstenedione administration. The use of androstenedione increased the serum concentrations of estradiol and estrone, suggesting an increased aromatization of the ingested androstenedione and/or testosterone derived from the exogenous androstenedione. The use of androstenedione was associated with decreased levels of HDL-C. These data provide evidence that androstenedione does not enhance adaptations to resistance training and may result in potentially serious adverse health consequences in young men.

The 17-ketosteroid epiandrosterone is a metabolite of testosterone precursor dehydroepiandrosterone (DHEA). Epiandrosterone have been considered to be merely inactive end product of DHEA, but may in fact be physiological effectors in their own right. It is formed in peripheral tissues, from which it is released into the circulation and is ultimately excreted in the urine. Epiandrosterone is only a weak androgen, but it is widely recognized to inhibit the pentose phosphate pathway and to decrease intracellular NADPH levels. Epiandrosterone may act as a L-type Ca2+ channel antagonist. Epiandrosterone mainly transformed into 17beta-hydroxylated derivatives, 7- or 16alpha-hydroxylated metabolites under NAD(P)H conditions, and 5alpha-androstane-3,17-dione under NAD(P)+ conditions. Epiandrosterone is used as an anabolic agent (dietary supplement, a precursor to dihydrotestosterone) to increase strength, muscle hardness and also improves libido.

Abietic acid (AA), a diterpene produced by conifer species, such as grand fir and lodgepole pine, has been reported to have anti-inflammatory and immunomodulatory effects and can be used as a wound-healing agent. Its treatment elevates cell migration and tube formation in human umbilical vein vascular endothelial cells by the activation of ERK and p38 MAPKs. In addition was shown, that abietic acid could be used as an antimetastatic agent or as an adjuvant for anticancer therapy. AA acts as a PPARα/γ dual activator to inhibit age-related inflammation by suppressing NF-κB and the MAPK/AP-1 pathway and can be a useful agent for improving skin photoaging.