Rama Satya Sri Kotipalli

Background: Alzheimer’s Disease (AD) involves Amyloid-Beta (Aβ) plaque accumulation, endothelial dysfunction, and cerebral hypoperfusion, with Ginkgo biloba flavonoids (e.g., quercetin, kaempferol glycosides in EGb761) emerging as nutraceuticals that enhance endothelial Nitric Oxide (NO) pathways for vasodilation while inhibiting Aβ fibrillisation. Aim: To review the dual mechanisms of Ginkgo flavonoids in boosting cerebral blood flow via endothelial Nitric Oxide Synthase (eNOS) activation and preventing Aβ aggregation, alongside their nutraceutical applications, preclinical/clinical evidence, and safety profile for AD management. Methods: Comprehensive literature synthesis from in vitro (e.g., DPPH, Thioflavin T (ThT) assays), animal models (e.g., hippocampal perfusion in AD rodents), clinical trials (e.g., EGb761 with donepezil), and network pharmacology analyses, structured around phytochemical profiles, mechanistic pathways, formulations, and future directions. Results: Flavonoids upregulate eNOS via PI3K/Akt (20-50% NO increase, 15-25% flow enhancement), scavenge Reactive Oxygen Species (ROS), inhibit arginase, and promote glymphatic clearance; They bind Aβ1-42 (Kd 1-5 μM), reduce fibril formation (40-82% ThT inhibition), downregulate Beta site Amyloid Precursor Protein Cleaving Enzyme 1 (BACE1), and suppress neuroinflammation. Clinical data show cognitive gains (+2.4 Korean Mini-Mental State Examination (K-MMSE) points) and Aβ oligomer reduction in adjunct therapy, with safe dosing (120-240 mg/day EGb761). Major Findings: Ginkgo flavonoids offer multifaceted AD benefits through NO-mediated perfusion and anti-amyloid actions, ideal for functional foods and supplements.

Essential oils (EOs) extracted from spices have been integral to traditional medicine and culinary applications for millennia, known for their multifaceted pharmacological properties. This chapter delves into a comprehensive overview of the chemical composition and pharmacological evaluation of EOs derived from commonly used spices, focusing on key constituents such as terpenes, esters, phenolic, coumarins, oxides, aldehydes, and aromatic compounds. The antimicrobial, anti-inflammatory, antibiotic, antifungal, analgesic, antispasmodic, antiseptic, antiviral, aromatherapy, antioxidant, and anticancer properties of these oils are reviewed in detail, substantiated by treatment modalities and extensive in vitro and in vivo research studies. The mechanism of action, such as modulation of signalling pathways and interaction with cellular targets, along with their structure activity relationships (SARs), are discussed to elucidate how these natural compounds showcase their promising therapeutic effects. Furthermore, the chapter addresses the extraction methods, drug development processes, quality control measures, regulatory guidelines, safety considerations, challenges, and future perspectives that are essential for the development of EO-based therapeutics. By integrating traditional knowledge with modern scientific research, this chapter emphasizes the importance of essential oils from spices in pharmacology and medicinal chemistry, highlighting their key potential for developing advanced and novel therapeutic agents.