BACKGROUND: Quercetin, a flavonoid found in plant-based foods, has a range of biological activities that may be beneficial for human health. The pharmacokinetic profile of quercetin remains, however, a limiting factor for its use as a nutritional supplement. Quercetin LipoMicel®-a novel delivery system encapsulating quercetin into a liquid micelle matrix-has been designed to address the low bioavailability issue associated with non-conjugated forms by improving the absorption of quercetin. OBJECTIVE: The purpose of this study was to evaluate the solubility and gastrointestinal absorption of quercetin in a novel Quercetin LipoMicel delivery system in healthy adult volunteers by comparing it with free quercetin and another commercial quercetin product. Several pharmacokinetic parameters were compared between these three formulations. METHODS: Twelve healthy adult male and female volunteers aged between 21 and 65, with BMIs under 30, participated in a non-blinded, crossover bioavailability study conducted with three quercetin products. Each treatment contained a total dose of 500 mg quercetin. Capillary whole blood samples from participants were collected serially at intervals from 0-24 hours. Quercetin concentrations were detected and measured by ultra-performance liquid chromatography (UHPLC) coupled to a Thermo QExactive Orbitrap Mass Spectrometer. Solubility of quercetin in water and simulated gastrointestinal media was determined by UHPLC. RESULTS: Oral absorption of quercetin was significantly enhanced with the LipoMicel delivery system compared to free quercetin. Improvements in in vitro gastric stability and intestinal solubility were observed with LipoMicel, leading to significantly higher blood concentration and enhanced duration of a stable concentration of quercetin in the body. Compared to free quercetin, 8- and 9-fold increases in AUC and Cmax were attained with the LipoMicel delivery system, and 10-fold higher quercetin plasma concentrations detected at 12 hours after administration. CONCLUSIONS: Quercetin LipoMicel represents an efficient delivery system for augmenting the bioavailability of quercetin in vivo . Significantly higher blood concentrations and a sustained release of quercetin over the study period was achieved following the administration of quercetin via the LipoMicel technology. Optimization in the in vivo bioavailability of quercetin may promote its salutary effects.
INTRODUCTION: Aponogeton madagascariensis (lace plant) is a freshwater aquatic flowering plant belonging to the family Aponogetonaceae that forms leaf perforations via programmed cell death (PCD). The lace plant has emerged as a novel model system for studying PCD in planta due to the predictability and accessibility of this process. Anthocyanins, and the balance between ROS and antioxidants, play a central role in regulating PCD in lace plant leaves. Aponogetonaceae family members have shown medicinal properties, including antioxidant and anticancer activities; however, nothing is known about the lace plant’s potential for medicinal use. Therefore, this study evaluated the anticancer activities of lace plant anthocyanin extracts. METHODS: Cell line growth and viability were assessed following exposure to lace plant leaf anthocyanin extracts. This study utilized a triple-negative breast cancer cell line, MDA-MB-231, two human ovarian epithelial cancer cell lines, OVCAR-8 and SKOV-3, along with a normal mammary epithelial cell line, MCF-10A. Furthermore, crude anthocyanin extracts were fractionated into anthocyanin and non-anthocyanin containing fractions and tested only on MDA-MB-231 cells. RESULTS AND DISCUSSION: The crude anthocyanin extracts from lace plant leaves inhibited the growth of MDA-MB-231, OVCAR-8, and SKOV-3 cells in a concentration-dependent manner and had no effect on MCF-10A cells. Lace plant crude anthocyanin extracts appeared to induce apoptosis in MDA-MB-231 cells. Interestingly, treatment with anthocyanin and non-anthocyanin fractions decreased the growth of MDA-MB-231, similarly to crude anthocyanin extracts, suggesting the presence of other anticancer compounds in the lace plant extracts. CONCLUSIONS: Lace plant crude anthocyanin extracts and corresponding fractions have in vitro anticancer activities.
