Phytochemical Composition and Cytoprotective Properties of the Endemic Sideritis sipylea Boiss Greek Species: A Valorization Study

Abstract

Sideritis sipylea Boiss. (Fam. Lamiaceae) is an endemic plant of the North Aegean Islands (Greece), commonly known as ironwort. Traditionally, its aerial parts have been used to relieve several ailments, especially gastrointestinal disorders, however, with scant knowledge about the pharmacological basis. In the present study, an endemic S. sipylea Greek species from Lesvos Island has been characterized for phytochemical composition and biological activities, in order to give a possible scientific basis to its traditional use and to highlight a further nutraceutical interest as a source of bioactive phytochemicals and extracts. Three different fractions obtained from a methanolic extract of S. sipylea aerial parts by using ethyl acetate with 10 (S10), 20 (S20), and 50% (S50) methanol as fractionation solvents were phytochemically characterized. Moreover, their antioxidant power and cytoprotective activity in different human cell lines were evaluated. The phytochemical analysis highlighted the presence of flavonoids, iridoids, and phenolic acids in all the tested samples. Particularly, the S10 fraction mainly contained iridoids, while S20 and S50 lavandulifolioside and chlorogenic acid, respectively. The fractions also showed antioxidant properties, S10 and S20 being the most potent. When assessed in human cholangiocytes, they counteracted the cytotoxicity of the tBOOH pro-oxidant agent, by reducing ROS levels and affecting GSH antioxidant system. The present findings highlight a possible interest in S10 and S20 fractions from S. sipylea as sources of bioactive molecules and stimulate further studies in order to characterize their possible application for nutraceutical and pharmaceutical purposes.

Identification of Volatile Molecules and Bioactivity of Gruyt Craft Beer Enriched with Citrus aurantium var. dulcis L. Essential Oil

“…Chelating activity of the tested samples towards both ferrous and ferric ions was evaluated by the ferrozine assay, according to previously published spectrophotometric methods and using quercetin and trolox as positive controls, respectively [ 41 ]. The percentage of activity was calculated as follows: 100 × (Acontrol − Asample)/Acontrol, where Acontrol is the absorbance of the vehicle while Asample is that of the tested sample.…”

“…The ferric ion reducing activity of the tested samples was evaluated by the ferrozine assay, using trolox as a positive control [ 41 ]. The levels of reduced iron were calculated as a percentage of the vehicle control as follows: 100 × (Asample)/Acontrol, where Asample is that of the tested sample while Acontrol is the absorbance of the vehicle.…”

Interaction of Garcinia cambogia (Gaertn.) Desr. and Drugs as a Possible Mechanism of Liver Injury: The Case of Montelukast

“…This cell line was a kind gift from Romina Mancinelli (Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Rome, Italy). Normal cholangiocytes were grown under standard conditions (37 °C and 5% CO 2 ) according to previously published methods [ 38 ]. In particular, RPMI-1640 medium supplemented with 10% fetal bovine serum (FBS), 100 U/mL penicillin, 100 µg/mL streptomycin, and 1% L-glutamine was used for H69 cultivation.…”

Characterization of the Chemopreventive Properties of Cannabis sativa L. Inflorescences from Monoecious Cultivars Grown in Central Italy

“…In particular, a protocol consisting of a 24 h treatment for the samples was applied. Conversely, an exposure schedule of 3 h was used for the positive control tBOOH (500 µM), due to its marked oxidative activity [30].…”

“…Intracellular levels of reduced (GSH) and oxidized (GSSG) glutathione were measured using a standardized HPLC-UV method, as previously described [30]. In particular, after the treatment of the HepG2 cells with a subtoxic concentration of hemp extracts (50 µg/mL) for 24 h, the GSH and GSSG levels were evaluated in cell lysates, calculated with respect to the corresponding calibration curves and normalized regarding cell viability.…”