Evaluation of the Anticancer, Anti-Inflammatory, and Antioxidant Properties of Various Extracts of Annona Squamosa L.

Background: Screening medicinal plants for their biological activities and phytochemicals is important for finding safe and potent new compounds for therapeutic use. The current investigation was conducted in extracts of Lebanese A. squamosa (leaves and bark) to evaluate the antioxidant, anticancer, and anti-inflammatory activities. Methods: Seven extracts were prepared by ultrasound-assisted extraction (UAE) or microwave-assisted extraction (MAE), and using various solvents. The evaluation of antioxidant activity was done using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the anticancer activity assessed on the colon cancer HCT116 cell line was determined by water-soluble tetrazolium-1 (WST-1) viability assay. Finally, the anti-inflammatory activity was investigated by measuring the secreted amounts of prostaglandin E2 (PGE2) and interleukin 6 (IL-6) using. Results: The total phenolic contents were in the range between 27.3 to 179.5 mg GAE/g of plant extract, while total flavonoid contents were between 8.3 to 150.8 mg RE/g of plant extract. DPPH assay showed high antioxidant activity for the methanolic extracts obtained by UAE in both natural dried leaves and bark with IC50 values of 9.3 and 12.6 μg.mL-1, respectively. For WST-1 assay, methanolic extracts obtained by UAE showed a potent anti-proliferative effect against the HCT116 cell line with IC50 values ranged from 0.18 to 0.88 μg.mL-1. Also, the western blot assay suggested that these extracts may inhibit the proliferation of the HCT 116 cell line by causing cell cycle arrest through activation of the p21 pathway. Significant anti-inflammatory activity was observed due to the decrease in the secretion of IL-6 in lipopolysaccharide (LPS)-stimulated THP-1 cells. Conclusion: Therefore, the present study revealed that the dried leaves and bark of Lebanese A. squamosa methanolic extracts obtained by UAE possess effective bioactivities, and thus hold the potential application in the pharmacological field

Effet différentiel des produits finaux de glycosylation avancée ou AGE (Advanced Glycation End products) sur l infection par le virus de l immunodéficience humaine de type 1 (VIH-1) (évaluation des molécules à visée microbicides)

La formation des AGEs ( Advanced Glycation End products ) figure parmi les modifications irréversibles causées par l hyperglycémie observée chez les patients sous HAART. Les AGEs constituent un groupe hétérogène de molécules formées par la glycosylation non enzymatique de protéines, d ADN et de lipides. Nous avons étudié le rôle des AGEs sur l infection des cellules dendritiques et des macrophages. Nous avons montré que les AGEs sont capables d inhiber l infection des cellules dendritiques et des macrophages par Le VIH-1. En effet, les AGEs diminuent l expression de CD4, CXCR4 et CCR5 à la surface des cellules dendritiques alors qu ils diminuent seulement l expression de CD4 sur les macrophages. Les AGEs sont capables d induire une augmentation de la production virale par une lignée chroniquement infectée par le VIH. L ensemble de ces résultats montre que les AGE ont un rôle à la fois comme activateur et comme inhibiteur de la réplication virale. Ensuite, nous avons évalué l activité anti-VIH-1 des lectines dérivées des plantes Hippeastrum hybrid et Galanthus nivalis agglutinin sur les cellules dendritiques et les cellules épithéliales.The formation of Advanced Glycation End products (AGE) appears as one of the irreversible modifications caused by hyperglycaemia observed in patients controlled by antiretroviral combination therapies (HAART). AGE forms a heterogeneous group of complex molecules generated by the non enzymatic glycosylation between reducing sugar and the amino groups of proteins. We studied the impact of AGE on the susceptibility of dendritic cells and macrophages to HIV infection. AGE are able to inhibit in vitro HIV infection of dendritic cells and macrophages. In fact, the AGEs reduced CD4, CXCR4, and CCR5 membrane expression on dendritic cells, while CD4 expression is the only one reduced on macrophages. AGEs are able to activate HIV-1 replication in persistently infected cell lines of monocytic. All these results show that AGE play a role both as an activator and as an inhibitor of viral replication. Then, we evaluated anti-HIV-1 activity of the lectines derived from the plants Hippeastrum hybrid and Galanthus nivalis agglutinin on dendritic cells and epithelial cells.PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF