Small but big leaps towards neuroglycomics:exploring N-glycome in the brain to advance the understanding of brain development and function

Glycosylation is a process that involves the addition of sugar moieties or glycans to different types of molecules,including proteins,lipids,and nucleic acids.Among these,protein glycosylation is one of the most prevalent forms of post-translational modification,playing a crucial role in biological complexity.With more than ten monosaccharides identified within mammalian brain cells and more than 1×1012 possible combinations,the heterogeneity of glycosylation is extensive(Conroy et al.,2021).The diversity of glycans and the complexity of their structures allow for a wide range of protein functions.N-glycans are one of the most abundant forms of glycans and are involved in various cellular functions.N-glycans can be added to proteins at specific sequons,Asn-X-Ser/Thr,and are classified into three main types in mature glycoproteins:high mannose,complex,and hybrid.High mannose N-glycans consist of 5-9 mannose residues linked to a chitobiose core and undergo processing into complex or hybrid forms in the Golgi apparatus(Varki et al.,2017).Complex N-glycans are more diverse and contain various branched structures such as antennae with fucose,galactose,and sialic acid residues.Hybrid N-glycans contain one or more complex branches in conjunction with an oligomannose branch(Fisher and Ungar,2016).Understanding the specific functions of these different types of N-glycans in protein regulation,folding,and function is an active area of research in the life sciences,including glycobiology.

Anti-Proliferative Effects of Ginsenosides Extracted from Mountain Ginseng on Lung Cancer

Objective： To investigate the effect of three major ginsenosides from mountain ginseng as anti- cancer substance and explore the underlying mechanism involved in lung cancer. Methods： The inhibitory proliferation of lung cancer by major five ginsenosides （Rbl, Rb2, Rgl, Rc, and Re） was examined using 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrazolium bromide assay. Calculated 50% inhibition （IC50） values of five ginsenosides were determined and compared each other. Apoptosis by the treatment of single ginsenoside was performed by fluorescence-assisted cytometric spectroscopy. The alterations of apoptosis-related proteins were evaluated by Western blot analysis. Results： The abundance of ginsenosides in butanol extract of mountain ginseng （BX-MG） was revealed in the order of Rbl, Rgl, Re, Rc and Rb2. Among them, Rbl was the most effective to lung cancer cell, followed by Rb2 and Rgl on the basis of relative IC50 values of IMR90 versus A549 cell. The alterations of apoptotic proteins were confirmed in lung cancer A549 cells according to the administration of Rbl, Rb2 and Rgl. The expression levels of caspase-3 and caspase-8 were increased upon the treatment of three ginsenosides, however, the levels of caspase-9 and anti-apoptotic protein Bax were not changed. Conclusion： Major ginsenosides such as Rbl, Rb2 and Rgl comprising BX-MG induced apoptosis in lung cancer cells via extrinsic apoptotic pathway rather than intrinsic mitochondrial pathway.