Bioaccessibility and Absorption Mechanism of Phenylethanoid Glycosides Using Simulated Digestion/Caco-2 Intestinal Cell Models

Abstract

Acteoside and salidroside are major phenylethanoid glycosides (PhGs) in Osmanthus fragrans Lour. flowers with extensive pharmacological activities and poor oral bioavailability. The absorption mechanisms of these two compounds remain unclear. This study aimed to investigate the bioaccessibility of these compounds using an in vitro gastrointestinal digestion model and to examine the absorption and transport mechanisms of PhGs using the Caco-2 cell model. The in vitro digestion model revealed that the bioaccessibility of salidroside (98.7 ± 1.35%) was higher than that of acteoside (50.1 ± 3.04%), and the superior bioaccessibility of salidroside can be attributed to its stability. The absorption percentages of total phenylethanoid glycoside, salidroside, and acteoside were 1.42-1.54%, 2.10-2.68%, and 0.461-0.698% in the Caco-2 model, respectively. Salidroside permeated Caco-2 cell monolayers through passive diffusion. At the concentration of 200 μg/mL, the apparent permeability ( P) of salidroside in the basolateral (BL)-to-apical (AP) direction was 23.7 ± 1.33 × 10 cm/s, which was 1.09-fold of that in the AP-to-BL direction (21.7 ± 1.38 × 10 cm/s). Acteoside was poorly absorbed with low P (AP to BL) (4.75 ± 0.251 × 10 cm/s), and its permeation mechanism was passive diffusion with active efflux mediated by P-glycoprotein (P-gp). This study clarified the bioaccessibility, absorption, and transport mechanisms of PhGs. It also demonstrated that the low bioavailability of acteoside might be attributed to its poor bioaccessibility, low absorption, and P-gp efflux transporter.

Salidroside ameliorates Adriamycin nephropathy in mice by inhibiting β‐catenin activity

“…Salidroside is a phenylpropanoid glycoside compound with various pharmacological activities, including anti‐oxidative stress, anti‐fatigue, anti‐inflammation, anti‐aging and anti‐diabetes . Salidroside has been found in food and traditional Chinese medicine, including Osmanthus fragrans flower, Olea europaea L. fruit, Striga asiatica , Cistanche deserticola Ma and Rhodiola rosea L . Current evidences indicate that salidroside has protective roles on early nephropathy in alloxan‐induced diabetic mice and db/db mice .…”

Fructosylation of Hydroxytyrosol by the β‐Fructofuranosidase from Xanthophyllomyces dendrorhous: Insights into the Molecular Basis of the Enzyme Specificity

“…Glucuronidated metabolites of HT have been also synthesized by chemical methods in order to analyze their bioactive properties . Interestingly, tyrosol and HT β‐glucosides are structural cores of several phenylethanoid‐based bioactive molecules present in medicinal plants …”

Exploring the compatibility mechanism of ShengDiHuang Decoction based on the in situ single‐pass intestinal perfusion model

“…When the transport of acteoside from a flower extract of Osmanthus fragrans Lour. in Caco‐2 cells was examined, acteoside was found to be a substrate for P‐gp, but not a substrate for BCRP and MRP2 (Zhou et al, ). This may be due to differences in the type and quantity of efflux transporter expression between the rat intestine and Caco‐2 cells.…”