Phloretin exhibits potential food-drug interactions by inhibiting human UDP-glucuronosyltransferases in vitro

Phloretin Transfersomes for Transdermal Delivery: Design, Optimization, and In Vivo Evaluation

BACKGROUND

Phloretin (Phl) is a flavonoid compound that contains multiple phenolic hydroxyl groups. It is found in many plants, such as apple leaves, lychee pericarp, and begonia, and has various biological activities, such as antioxidant and anticancer effects. The strong hydrogen bonding between Phl molecules results in poor water solubility and low bioavailability, and thus the scope of the clinical application of Phl is limited. Therefore, it is particularly important to improve the water solubility of Phl for its use to further combat or alleviate skin aging and oxidative damage and develop antioxidant products for the skin. The purpose of this study was to develop and evaluate a phloretin transfersome gel (PTG) preparation for transdermal drug delivery to improve the bioavailability of the drug and delay aging.

METHODS

Phloretin transfersomes (Phl-TFs) were prepared and optimized by the thin-film dispersion-ultrasonication method. Phl-TFs were characterized by transmission electron microscopy (TEM), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). The Log P method was used to determine the solubility of the Phl-TFs. The skin penetration ability of the prepared PTG was evaluated using the Franz diffusion cell method. In addition, the in vivo pharmacokinetics of PTG were studied in rats, and an antioxidant activity investigation was conducted using a D-gal rat model.

RESULTS

Phl-TFs were successfully prepared with a Soybean Phosphatidylcholine (SPC)/CHOL ratio of 2.7:1 w/v, a phloretin concentration of 1.3 mg/mL, a hydration time of 46 min, an ultrasound time of 5 min, and an ultrasound power of 180 W. The Log P was 2.26, which was significantly higher than that of phloretin (p < 0.05, paired t test). The results of the in vitro penetration test demonstrated that the cumulative skin penetration of the Phl-TFs after 24 h was 842.73 ± 20.86 μg/cm2. The data from an in vivo pharmacokinetic study showed that the Cmax and AUC of PTG were 1.39- and 1.97-fold higher than those of the phloretin solution gel (PSG), respectively (p < 0.05, paired t test). The experimental results in aging rats showed that PTG had a better antioxidant effect.

CONCLUSIONS

Phl-TFs and PTG preparations with a good shape, safety, and stability were successfully prepared. In vivo pharmacokinetics and preliminary antioxidant experiments further verified the transdermal penetration and antioxidant activity of the phloretin transdermal drug delivery preparation, providing an experimental basis for its further development.

Functionalization of Polyhydroxyalkanoates (PHA)-Based Bioplastic with Phloretin for Active Food Packaging: Characterization of Its Mechanical, Antioxidant, and Antimicrobial Activities

The formulation of eco-friendly biodegradable packaging has received great attention during the last decades as an alternative to traditional widespread petroleum-based food packaging. With this aim, we designed and tested the properties of polyhydroxyalkanoates (PHA)-based bioplastics functionalized with phloretin as far as antioxidant, antimicrobial, and morpho-mechanic features are concerned. Mechanical and hydrophilicity features investigations revealed a mild influence of phloretin on the novel materials as a function of the concentration utilized (5, 7.5, 10, and 20 mg) with variation in FTIR e RAMAN spectra as well as in mechanical properties. Functionalization of PHA-based polymers resulted in the acquisition of the antioxidant activity (in a dose-dependent manner) tested by DPPH, TEAC, FRAR, and chelating assays, and in a decrease in the growth of food-borne pathogens (Listeria monocytogenes ATCC 13932). Finally, apple samples were packed in the functionalized PHA films for 24, 48, and 72 h, observing remarkable effects on the stabilization of apple samples. The results open the possibility to utilize phloretin as a functionalizing agent for bioplastic formulation, especially in relation to food packaging.

Assessment of the inhibition risk of chlorophenol substances on cytochrome P450 via cocktail inhibition assays

Chlorophenols (CPs) are widespread pollutants in nature. CPs have raised significant concern due to their potential hepatotoxic effects on humans. This research aimed to ascertain the inhibitory potential of eleven CPs (2-CP, 3-CP, 4-CP, 2,4-DCP, 2,3,4-TCP, 2,4,5-TCP, 2,4,6-TCP, 2,3,4,5-TeCP, 2,3,4,6-TeCP, 2,3,5,6-TeCP, and PCP) on nine human CYP isoforms (CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4). The CPs that inhibit the activity of CYP isoforms were detected with human liver microsomes (HLM) using a cocktail approach in vitro. The results demonstrated that trichlorophenols, tetrachlorophenols, and PCP strongly inhibited CYP2C8 and CYP2C9. The half inhibition concentration (IC₅₀) value of 2,3,4,6-TeCP and PCP for CYP2C8 inhibition was 27.3 μM and 12.3 μM, respectively. The IC₅₀ for the inhibition of 2,4,6-TCP, 2,3,4,6-TeCP and PCP towards CYP2C9 were calculated to be 30.3 μM, 5.8 μM and 2.2 μM, respectively. 2,3,4,6-TeCP, and PCP exhibited non-competitive inhibition towards CYP2C8. 2,4,6-TCP, 2,3,4,6-TeCP, and PCP exhibited competitive inhibition towards CYP2C9. The inhibition kinetics parameters (Ki) were 51.51 μM, 22.28 μM, 37.86 μM, 7.27 μM, 0.68 μM for 2,3,4,6-TeCP-CYP2C8, PCP-CYP2C8, 2,4,6-TCP-CYP2C9, 2,3,4,6-TeCP-CYP2C9, PCP-CYP2C9, respectively. This study also defined clear structure-activity relationships (SAR) of CPs on CYP2C8, supported by molecular docking studies. Overall, CPs were found to cause inhibitory effects on CYP isoforms in vitro, and this finding may provide a basis for CPs focused on CYP isoforms inhibition endpoints.