The silibinin-loaded Zein-β cyclodextrin nano-carriers (SZBC-NCs) as a novel selective cancer cell drug delivery system in HT-29 cell line

Entrapping phytochemical bioactive compounds into nano-structured biocompatible polymers has been successfully utilized for improving cancer treatment efficiency. Silibinin is a potent compound that shows promising anticancer properties. In the present study, the Zein-β-cyclodextrin complex was used to encapsulate silibinin and evaluate the induced cell death type and cytotoxic impacts on human cancer cells. The silibinin-loaded Zein-β cyclodextrin nano-carriers (SZBC-NCs) were synthesized utilizing a gradual ultrasound-mediated homogenization technique and characterized by Zeta potential, DLS, FESEM, and FTIR analysis. The SZBC-NCs' antioxidant activity was studied by conducting ABTS and DPPH radical scavenging assays. Finally, the SZBC-NCs selective toxicity and cellular death induction mechanism were studied on the HT-29 and AGS cancer cells by measuring the cell survival and apoptotic gene (Caspase 3, 9), respectively, which were verified by conducting the DAPI staining analysis. The negatively charged (- 27.47 mV) nanoparticles (286.55 nm) showed significant ABTS and DPPH radical scavenging activity. Moreover, the remarkable decrease in the IC50 concentrations of the SZBC-NCs among the HT-29 and AGS cancer cell lines exhibited their selective cytotoxic potential. Also, the overexpressed apoptotic (Caspases 3 and 9) and down-regulated necrotic (NFKB) gene expressions following the SZBC-NCs treatment doses indicated the apoptotic activity of SZBC-NCs, which were verified by the increased apoptotic morphology of the DAPI-stained HT-29 cancer cells. The antioxidant and colon cancer cell-related apoptotic activity of the SZBC-NCs make it an appropriate anti-colon cancer nano delivery system. Therefore, they can potentially be used as a safe efficient colon cancer treatment strategy. However, further in vivo experiments including animal cancer models have to be studied.

A Multifunctional Scaffold for Bone Infection Treatment by Delivery of microRNA Therapeutics Combined With Antimicrobial Nanoparticles

Treating bone infections and ensuring bone repair is one of the greatest global challenges of modern orthopedics, made complex by antimicrobial resistance (AMR) risks due to long-term antibiotic treatment and debilitating large bone defects following infected tissue removal. An ideal multi-faceted solution would will eradicate bacterial infection without long-term antibiotic use, simultaneously stimulating osteogenesis and angiogenesis. Here, a multifunctional collagen-based scaffold that addresses these needs by leveraging the potential of antibiotic-free antimicrobial nanoparticles (copper-doped bioactive glass, CuBG) to combat infection without contributing to AMR in conjunction with microRNA-based gene therapy (utilizing an inhibitor of microRNA-138) to stimulate both osteogenesis and angiogenesis, is developed. CuBG scaffolds reduce the attachment of gram-positive bacteria by over 80%, showcasing antimicrobial functionality. The antagomiR-138 nanoparticles induce osteogenesis of human mesenchymal stem cells in vitro and heal a large load-bearing defect in a rat femur when delivered on the scaffold. Combining both promising technologies results in a multifunctional antagomiR-138-activated CuBG scaffold inducing hMSC-mediated osteogenesis and stimulating vasculogenesis in an in vivo chick chorioallantoic membrane model. Overall, this multifunctional scaffold catalyzes killing mechanisms in bacteria while inducing bone repair through osteogenic and angiogenic coupling, making this platform a promising multi-functional strategy for treating and repairing complex bone infections.

Salicylate induces reactive oxygen species and reduces ultraviolet C susceptibility in Staphylococcus aureus

This study demonstrates that growth of Staphylococcus aureus in the presence of salicylate reduces ultraviolet C (UVC)-induced cell death and increases the generation of reactive oxygen species (ROS). In addition, compounds that scavenge ROS (N-acetylcysteine, glutathione, catalase and superoxide dismutase) reverse the increased UVC survival induced by growth in the presence of salicylate, while ROS donors (tert-butylhydroperoxide, H2O2 and NaClO) enhance survival of salicylate challenged cultures. Collectively, these findings suggest that ROS production induced by growth in the presence of salicylate protects S. aureus from UVC-induced cell death.