Mitigating the skin phototoxicity of sonodynamic therapy via singlet oxygen-consuming metal-organic frameworks.

Sonodynamic anti-cancer therapy relies on the highly active singlet oxygen to induce potent cell death. However, the non-specific biodistribution of sonosensitizers post systemic administration results in a significant accumulation in the skin, and hence the daylight-induced phototoxicity. Here, we report a smart metal-organic framework-based nanocarrier with titanium dioxide (TiO) as the sonosensitizer for reduced phototoxicity in the skin.

Molecular Dynamics Study of the Effect of Charge and Glycosyl on Superoxide Anion Distribution near Lipid Membrane.

To examine the effects of membrane charge, the electrolyte species and glycosyl on the distribution of negatively charged radical of superoxide anion (·O) around the cell membrane, different phospholipid bilayer systems containing ·O radicals, different electrolytes and phospholipid bilayers were constructed through Charmm-GUI and Amber16. These systems were equilibrated with molecular dynamics by using Gromacs 5.0.

Stimuli-responsive cancer nanomedicines inhibit glycolysis and impair redox homeostasis.

The solid tumors are characterized with oxidative stress and metabolic reprogramming, which has been independently used for targeted tumor monotherapy. However, the potential of targeting metabolism-redox circuit in tumor therapy has long been neglected. Herein, we report a hybrid nanocarrier for concurrent targeting of glycolysis and redox balance in the current work.

Synthesis, molecular docking, and binding Gibbs free energy calculation of β-nitrostyrene derivatives: Potential inhibitors of SARS-CoV-2 3CL protease.

The outbreak of novel coronavirus disease 2019 (COVID-19), caused by the novel coronavirus (SARS-CoV-2), has had a significant impact on human health and the economic development. SARS-CoV-2 3CL protease (3CLpro) is highly conserved and plays a key role in mediating the transcription of virus replication. It is an ideal target for the design and screening of anti-coronavirus drugs.

Site-Directed Mutation of Salicylate Decarboxylase Gene and Mechanism of Ginkgo Acid Decarboxylation.

Ginkgo seed is an important Chinese medicine and food resource in China, but the toxicity of ginkgo acid in it limits its application. Previous studies have found that salicylic acid decarboxylase (Sdc) has a decarboxylation degradation effect on ginkgo acid. In order to improve the decarboxylation ability of Sdc to Ginkgo acid, 11 residues of the Sdc around the substrate (salicylic acid) were determined as mutation targets according to the analysis of crystal structure of Sdc (PDB ID:6JQX), from Trichosporon moniliiforme WU-0401, and a total of 30 single point mutant enzymes and one compound mutant enzyme were obtained.

DFT investigation on the carbonate radical formation in the system containing carbon dioxide and hydroxyl free radical.

A density functional theory (DFT) study was performed to explore the reaction mechanisms of CO-containing systems(CO,HCO,HCO) with hydroxyl radical using UM06-2X/aug-cc-pVTZ for geometry optimization and UCCSD(T)-F12/cc-pVDZ-F12 for electronic energies, the effect of solvation is considered using the implicit solvent model with two explicit water molecule. The final transformation of hydroxyl radical into carbonate anion radical by reaction with CO-containing system was studied. The energy barriers, Gibbs free energy, reaction enthalpy changes and reaction rate constants for reaction of CO-containing systems by hydroxyl radical are calculated.

Triggered All-Active Metal Organic Framework: Ferroptosis Machinery Contributes to the Apoptotic Photodynamic Antitumor Therapy.

Nanoscale photodynamic therapy (PDT) is an appealing antitumor modality for which apoptosis is the major mechanism of toxicity induction. It was postulated that the highly reactive singlet oxygen in PDT could deplete glutathione (GSH) and activate ferroptosis, the extent to which could be further manipulated by a redox-responsive nanocarrier. To validate this, a disulfide-bearing imidazole ligand coordinated with zinc to form an all-active metal organic framework (MOF) nanocarrier where a photosensitizer (chlorin e6/Ce6) was encapsulated.

Gated Mesoporous Silica Nanocarriers for Hypoxia-Responsive Cargo Release.

Mesoporous silica nanocarriers (MSNs) are appealing in terms of their large cavity surface area and high loading capacity, but they have been suffering from premature cargo release. Herein, we report a gated smart MSN that is sensitive to low oxygen concentration (i.e.