Pregnenolone is an endogenous steroid hormone synthesized from cholesterol. As a -Ïparent hormone-�, pregnenolone can be converted to other hormones, including the sex hormones. For example, pregnenolone can be converted to progesterone, which can then be converted to DHEA, the precursor of androstenedion, the precursor to testosterone and estrone. Pregnenolone is also a neurosteroid having anxiolytic properties. It is found in high concentrations in the brain, where along with other neurosteroids, it impacts synaptic function, is neuroprotective, and enhances myelinization.