Alzheimer’s disease (AD) is a progressive, multifactorial, and unremitting neurodegenerative disease characterized by memory loss, personality changes, and cognitive impairment. It has become more prevalent in recent years. Therefore, understanding the pathophysiology of AD and developing efficient therapeutic strategies are essential. Moreover, the progression of the disease is unaffected by the pharmaceutical approaches discovered to date. Additionally, the failure of over 200 potential drug candidates in clinical trials over the past decade suggests the complexity and difficulty of both the disease and its underlying causes. Therefore, research focused on medicinal plant-based natural products in the search for novel neuroprotective therapeutic candidates for AD is essential. Indeed, several scientific investigations have demonstrated the efficacy of many medicinal plants and their principal phytochemicals in the treatment of AD. This review article covered the pathophysiological mechanisms of AD, the necessity for natural products as anti-AD treatments, and the most recent preclinical studies revealing the function of neuroprotective medicinal plants and their bioactive compounds in the effective management of AD. In addition, the review also presents clinical trial data of promising anti-AD formulations/agents of plant origin. Revealing recent findings and highlighting the clinical trial data related to the development of new treatments for AD would promote further research in this field and pave the way for the development of more effective and safe treatments for this debilitating disease.

Ghrelin is a peptide released by the endocrine cells of the stomach and the neurons in the arcuate nucleus of the hypothalamus. It modulates both peripheral and central functions. Although ghrelin has emerged as a potent stimulator of growth hormone release and as an orexigenic neuropeptide, the wealth of literature suggests its involvement in the pathophysiology of affective disorders including depression. Ghrelin exhibits a dual role through the advancement and reduction of depressive behavior with nervousness in the experimental animals. It modulates depression-related signals by forming neuronal networks with various neuropeptides and classical neurotransmitter systems. The present review emphasizes the integration and signaling of ghrelin with other neuromodulatory systems concerning depressive disorders. The role of ghrelin in the regulation of neurosynaptic transmission and depressive illnesses implies that the ghrelin system modulation can yield promising antidepressive therapies.