REGULATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS BY PHYTOSTEROL: ACTIONS AND MECHANISM OF ACTION

Phytosterols (PS), commonly referred to as plant sterols, are naturally occurring chemicals found in plants that resemble cholesterol in structure but have an additional methyl (campesterol) or ethyl (β-sitosterol) group in the side chain. The present review was based on the regulation of the hypothalamic-pituitary-adrenal axis by phytosterol: actions and mechanism of action. PS have been shown to have endocrine-disrupting properties, and studies on humans, rats, mice, goldfish (Carassius auratus), and Japanese quail have all reported experiencing this effect. Dietary PS has been shown to accumulate in the brain lately. Dietary β-sitosterol has the ability to cross the blood–brain barrier (BBB) and build up permanently in the membranes of brain cells. The stress response, which consists of a complex interplay between elements of the central nervous system (CNS) and peripheral systems such the endocrine, immunological, and cardiovascular systems, is triggered by exposure to environmental, physical, or physiological stressors. Under stressful circumstances, the HPA axis mediates the physiological maintenance of homeostasis. In conclusion, adult male quails fed PS alone had lower testosterone concentrations in their plasma and pituitary without appreciably changing their levels of LH. Furthermore, LH release from the pituitary gland and testosterone release from the testes were both markedly increased by cGnRH-1 stimulation. In contrast to control animals, quails fed PS had lower amounts of testosterone and LH.