Cyanocobalamin promotes muscle development through the TGF-ß signaling pathway.

Cyanocobalamin (CNCbl, the compound name of Vitamin B12) is the only mineral vitamin that is essential for growth and development and cannot be produced by animals. Some studies have found that CNCbl can promote the proliferation and migration of C2C12 cells, but the mechanism by which it affects muscle development is still unknown. In this study, we elucidated the effect of CNCbl on muscle development and studied its underlying mechanism. CNCbl could promote the differentiation of C2C12 cells and upregulate Acvr1, p-Smad2 and p-Smad3 in the TGF-ß signaling pathway in vitro. CD320 (the receptor in cell surface for binding with CNCbl transporter transcobalamin II) inhibition could reduce the uptake of CNCbl and significantly downregulate the expression of differentiation marker proteins MyoG and MYH2. Furthermore, the levels of p-Smad2 and p-Smad3 were also reduced with the inhibition of CD320, even though CNCbl was added to the C2C12 culture medium. In addition, the injection of CNCbl could accelerate the process of mouse muscle injury repair, enlarge the diameter of newly formed myofibers and upregulate the expression of MYH2, PAX7, CD320, Acvr1, p-Smad2 and p-Smad3 in vivo. These results suggest that CNCbl can promote muscle development and may play its role by regulating the expression of Acvr1, p-Smad2 and p-Smad3 related to the TGF-ß signaling pathway.

Allyl phenyl selenides as H2O2 acceptors to develop ROS-responsive theranostic prodrugs.

Reactive oxygen species (ROS)-responsive prodrugs have received significant attention due to their capacity to target tumors to relieve the side effects caused by chemotherapy. Herein, a series of novel H2O2-activated theranostic prodrugs (CPTSe1-CPTSe7) were developed containing allyl phenyl selenide moieties as H2O2 acceptors. Compared with conventional boronate ester-based prodrug CPT-B, CPTSe1 was more stable in human plasma and showed a more complete release of camptothecin (CPT) in H2O2 inducing experiment. The selectively activated fluorescence signals of CPTSe1 in tumor cells make it useful for real-time monitoring of CPT release and H2O2 detection. Furthermore, excellent selectivity of CPTSe1 was achieved for tumor cells over normal cells. Our results provide a new platform for the development of H2O2-responsive theranostic prodrugs.

Metal-free photo-induced sulfidation of aryl iodide and other chalcogenation.

A photo-induced C-S radical cross-coupling of aryl iodides and disulfides under transition-metal and external photosensitizer free conditions for the synthesis of aryl sulfides at room temperature has been presented, which features mild reaction conditions, broad substrate scope, high efficiency, and good functional group compatibility. The developed methodology could be readily applied to forge C-S bond in the field of pharmaceutical and material science.

Vitamin C Promotes Muscle Development Mediated by the Interaction of CSRP3 with MyoD and MyoG.

Previous studies have reported that vitamin C (VC), an essential nutrient, exerts beneficial effects on muscle health. However, the molecular mechanism involved in the VC-mediated regulation of muscle development is still unclear. The roles of VC in muscle development and the underlying molecular mechanisms were examined using cell and molecular biology, transcriptomics, proteomics, and animal experiments in this study. VC upregulated the expression of sodium-dependent vitamin C transporter 2 (SVCT2) and cysteine rich protein 3 (CSRP3). Additionally, VC promoted the differentiation of C2C12 cells and the repair of mouse muscle injury by upregulating the nuclear translocation of CSRP3, which subsequently interacted with MyoD and MyoG. This study provided a theoretical basis for elucidating the mechanism underlying the VC-mediated regulation of muscle development, as well as for developing animal nutritional supplements and therapeutic drugs for muscle diseases.

Triazene as the Directing Group Achieving Highly Ortho-Selective Diborylation and Sequential Functionalization.

This study describes a regioselective ortho,ortho'-diborylation of aromatic triazenes catalyzed by [Ir(OMe)(cod)]2 in near-quantitative yields without an additional ligand. Aromatic triazenes act as both substrates and ligands. The X-ray structures of 2a and 2p indicate that the monoborylation products could promote the occurrence of diborylation. The synthesized triazene-substituted diboronate esters could undergo a variety of transformations including directing group removal. One-pot sequential modification provides a short entry to densely functionalized arenes.

Molybdenum disulfide nanosheets vertically grown on self-supported titanium dioxide/nitrogen-doped carbon nanofiber film for effective hydrogen peroxide decomposition and "memory catalysis".

A self-supporting catalyst consisting of 1D/2D vertical molybdenum disulfide@titanium dioxide/nitrogen-doped carbon nanofiber (MoS2@TiO2/NCNFs) was prepared and tested. It showed efficient hydrogen peroxide (H2O2) decomposition to generate hydroxyl radical (OH) and degradation of various pollutants under solar irradiation. The contribution of the increase in MoS2 edges for decomposing H2O2 was 0.0698 min-1. That is 9.83 times the rate of the original MoS2 edges resulting from the vertical structure. Specially, the catalyst degraded various aromatic pollutants even in the dark by releasing electrons stored in its graphite component to realize "memory catalysis". Also, it exhibited high degradation efficiency under outdoor solar irradiation. The catalyst was easily separated from the treated water, avoiding complex separation processes. All these features suggest this catalyst has great potential in practical water and sewage treatment applications.