Drug-Initiated Synthesis of Cladribine-Based Polymer Prodrug Nanoparticles: Biological Evaluation and Structure Activity Relationships

International audienceBy using two reversible deactivation radical polymerization techniques, either nitroxide-mediated polymerization or reversible addition-fragmentation chain transfer polymerization, the "drug-initiated" approach was applied to cladribine (CdA) as an anticancer drug to synthesize small libraries of well-defined and self-stabilized CdA-based polymer prodrug nanoparticles, differing from the nature and the molar mass of the grown polymer, and the nature of the linker between CdA and the polymer, thus allowing structure-cytotoxicity relationships to be determined. Their biological evaluation was investigated in vitro on L1210 cancer cells. The preparation of fluorescent CdA-based nanoparticles with excellent imaging ability was also reported by applying the "drug-initiated" approach to an aggregation-induced emission-active dye

Leaf-buds of Pistacia atlantica: a novel source of bioactive molecules with high anti-inflammatory, antioxidant, anti-tyrosinase and antimicrobial properties

In this study, for the first time, the anti-inflammatory, antioxidant, anti-tyrosinase and antimicrobial property of P. atlantica Desf. subsp. atlantica leaf-bud extract have been investigated. The anti-inflammatory activity was determined in vivo by reducing carrageenan-induced hind paw edema in mice, while the antiradical function was evaluated using DPPH, total antioxidant capacity (TAC) and reduction power assays. The extract induced a significant reduction of the edema, from 1 to 6 h in a dose-dependent manner (150, 200 and 300 mg/kg). Histological observations of the inflamed tissues also confirmed this. An effective antioxidant activity of the plant samples was demonstrated, showing an EC50 = 0.183 ± 0.005 mg/mL for the DPPH test, a value of 28.776 ± 2.541 mg AAE/g for the TAC and an EC50 = 0.136 ± 0.003 mg/mL for reducing power. The leaf-bud extract also revealed a good antimicrobial activity against S. aureus and L. monocytogenes (mean diameter of inhibition zones of 13.2 and 17.0 mm, respectively), while a slight antifungal effect was observed. The plant preparation was then documented to inhibit tyrosinase activity, with an EC50 value of 0.098 ± 0.00 mg/mL in a dose-dependent manner. HPLC–DAD analysis revealed that dimethyl-allyl caffeic acid and rutin were the most abundant molecules. The current data documented that P. atlantica leaf-bud extract has strong biological properties and constitutes a potential source of pharmacological molecules

Echinops spinosissimus Turra Root Methanolic Extract: Characterization of the Bioactive Components and Relative Wound Healing, Antimicrobial and Antioxidant Properties

Echinops spinosissimus Turra subsp. bovei (Asteraceae) is a medicinal plant in western Algeria. Traditionally, roots and inflorescences are employed as hypertensive agents and in the treatment of hemorrhoids. The current study evaluates the chemical composition, antioxidant, antimicrobial, and wound-healing properties of the root methanolic extract from E. spinosissimus subsp. bovei. The content of total phenolics, flavonoids, and tannins was determined. In addition, the phenolic profile was typified. The studied plant extract resulted in being primarily composed of Apigenin, Kaempferol, and their derivatives. The total phenolic content was equal to 95.31 ± 2.90 mg GAE/g DW, while the number of flavonoids and condensed tannins was 16.01 ± 0.16 mg CE/g DW and 8.30 ± 0.65 mg CE/g DW, respectively. The methanolic extract was found to exhibit antioxidant activity towards the DPPH radical, with an IC50 of 7.99 ± 0.28 mg/mL and a TAC of 30.30 ± 0.54 mg AAE/g DW, as well as an antibacterial effect, especially against P. aeruginosa. No significant wound-healing property was observed, even though the histopathological observations showed enhanced wound-healing quality. According to our evidence, E. spinosissimus could represent a source of phytochemicals with potential beneficial effects for human health in terms of antioxidant and antibiotic properties, although further investigations on this species are needed

Antimicrobial and anti-inflammatory activities of three halophyte plants from Algeria and detection of some biomolecules by HPLC-DAD

Antimicrobial activity of hydroalcoholic extracts (30/70) from leaves and stems of three halophytes (Tamarix africana, Arthrocnemum macrostachyum and Suaeda fruticose) was investigated. In vivo toxicological study and anti-inflammatory activity of leaf extract of T. africana were tested on carrageenan-induced inflammatory paw edema. T. africana possessed significant anti-inflammatory activity at 150 and 300 mg/kg confirmed by histological study of inflamed tissues. Six phenolic acids and 10 flavonoids where identified by HPLC–DAD. Gallic acid, Rutin and Kaempferol-3-O-glucoside were the major compounds. For the antibiotic assays, S. fruticosa leaf extract exhibited strong bactericidal power against S. aureus with MBC of 1.25 mg/mL whereas T. africana leaf and stem samples exhibited a significant bactericidal activity against S. aureus and B. subtilis compared to the negative control (Ampicillin and Chloramphenicol). Crude leaf and stem extracts from T. africana and stem extract from S. fruticosa exhibited a strong antifungal effect against C. albicans