Histopathological Impact of Exogenous Chemicals on the Pituitary Gland and Neuroprotective Role of Natural Plant Extracts (NPEs)

This chapter provides a comprehensive review of the histopathological impacts of exogenous chemicals on the pituitary gland and explores the ameliorative potential of Natural Plant Extracts (NPEs) as the neuroprotective agents. The pituitary gland functions as a critical link between the nervous and endocrine systems and anatomically comprises two major parts: the adenohypophysis and the neurohypophysis. The adenohypophysis is a highly vascular region composed of epithelial cells or follicles separated by sinusoids and supported by reticular tissue. Its specialized cells, acidophils and basophils, secrete key hormones essential for maintaining endocrine homeostasis. The pituitary gland is also a principal target of various exogenous chemicals, including insecticides, xenobiotics, environmental pollutants, flame retardants, pesticides, pyrethroids, and aerosols. Bioaccumulation of these agents leads to structural and functional impairments, lipid peroxidation, and oxidative stress, thereby disrupting hormone synthesis and secretion. Recent studies have investigated the neuroprotective efficacy of diverse NPEs in mitigating these toxic effects. These extracts enhance neuronal function by modulating molecular pathways, scavenging free radicals, and activating antioxidant enzymes that reduce neuronal stress. For example, Nigella sativa extract demonstrates significant rehabilitative effects against histopathological damage in the pituitary and hypothalamus, while Vitex agnus-castus extract improves the pituitary-gonadal axis. Overall, NPEs play a pivotal role in enhancing antioxidant defenses and supporting pituitary recovery. Pituitary rehabilitation remains a complex and underexplored area in histopathology due to limited available data. This review emphasizes the therapeutic potential of NPEs as the promising agents for restoring pituitary integrity following exposure to exogenous toxicants.