Assessment of the Properties and Mechanism of Three Lotus ( Nelumbo nucifera Gaertn.) Parts for Sleep Improvement

Lotus leaves (LL), petals (LP), and seeds (LS) are believed to have properties that can potentially improve sleep. However, their efficacy in improving sleep has not yet been fully validated. This study aimed to investigate the multitarget mechanisms of extracts from these lotus parts for sleep improvement using chemical analysis, bioactivity assessment, meta-analysis, network pharmacology evaluation, and molecular docking studies. The chemical components in LL, LP, and LS were qualitatively detected using ultra-high-performance liquid chromatography-ultraviolet-quadrupole time-of-flight tandem mass spectrometry, their total flavonoid and phenolic contents were determined, and their 2,2-diphenyl-1-picrylhydrazyl scavenging activity was estimated. Subsequently, relevant literature was collected for meta-analysis. Finally, potential targets were predicted using network pharmacology, and the results were validated by molecular docking studies. A total of 48 compounds, including 16 flavonoids, 26 alkaloids, 2 amino acids, and 4 other compounds, were identified from the lotus extracts. LL had the highest total flavonoid content, while LS had the highest total phenolic content. Extracts from both parts exerted significant antioxidant effects. A meta-analysis identified the potential of lotus to improve sleep. Armepavine, asimilobine, nuciferin, and luteolin were identified as key components, and AKT1, EGFR, DRD2, and PIK3R1 were revealed as key targets. PI3K-Akt was identified as a key signaling pathway. This study provides an important reference for studying the role of the lotus in improving sleep quality.