Antioxidant, Anti-Inflammatory and Antiproliferative Effects of Osmanthus fragrans (Thunb.) Lour. Flower Extracts

Abstract

Osmanthus fragrans (Thunb.) Lour. flowers (OF-F) have been traditionally consumed as a functional food and utilized as folk medicine. This study evaluated the antioxidant, anti-inflammatory and cytotoxic effects of OF-F extracts on prostate cancer cells (DU-145) and determined possible protein-ligand interactions of its compounds in silico. The crude OF-F extracts—water (W) and ethanol (E) were tested for phytochemical screening, antioxidant, anti-inflammatory, and anti-cancer. Network and molecular docking analyses of chemical markers were executed to establish their application for anticancer drug development. OF-F-E possessed higher total polyphenols (233.360 ± 3.613 g/kg) and tannin (93.350 ± 1.003 g/kg) contents than OF-F-W. In addition, OF-F-E extract demonstrated effective DPPH scavenging activity (IC50 = 0.173 ± 0.004 kg/L) and contained a high FRAP value (830.620 ± 6.843 g Trolox/kg). In cell culture experiments, OF-F-E significantly reduced NO levels and inhibited cell proliferation of RAW-264.7 and DU-145 cell lines, respectively. Network analysis revealed O. fragrans (Thunb.) Lour. metabolites could affect thirteen molecular functions and thirteen biological processes in four cellular components. These metabolites inhibited key proteins of DU-145 prostate cancer using molecular docking with rutin owning the highest binding affinity with PIKR31 and AR. Hence, this study offered a new rationale for O. fragrans (Thunb.) Lour. metabolites as a medicinal herb for anticancer drug development.

Osmanthus fragrans Flavonoid Extract Inhibits Adipogenesis and Induces Beiging in 3T3-L1 Adipocytes

“…In addition, the floral aroma of O. fragrans has been found to directly inhibit appetite neuropeptides in the hypothalamus, which can contribute to reducing food intake and ultimately aiding in weight management [30]. It was shown that intragastric administration of cinnamon extract to mice for 15 consecutive days effectively inhibited acetaminopheninduced elevation of glutamine aminotransferase, ameliorated lipid peroxidation in the liver and lungs, and significantly reduced vacuolization in liver tissue [31]. Loganic acid, a major secondary metabolite of O. fragrans, reduces the expression of key lipogenesis-related genes, such as lipocalin and lipoprotein lipase, and has anti-adipogenic and anti-osteoporotic effects [32,33].…”