Citations

ABSTRACT As a principal metabolite of ginsenosides, compound K (CK) exhibits remarkable antioxidant, anti‐inflammatory, antidiabetic, and anticancer bioactivities. However, CK is naturally scarce in ginseng and its industrial application is limited by the lack of efficient deglycosylating enzymes for large‐scale CK bioproduction. Here, we report a synthetic biology‐driven approach for high‐yield CK production via recombinant β‐glycosidase‐mediated bioconversion of the polar ginsenoside Rb1. The β‑glycosidase‐encoding gene was introduced into Escherichia coli BL21 (DE3), and the resulting engineered strain produced 2.1 g/L β‑glycosidase in shake flasks and 10.1 g/L in a 5‐L fermentor. The crude β‐glycosidase exhibited excellent enzymatic activity; at a concentration of 1.5 g/L, it converted 95% of the Rb1 substrate (initial concentration 10 g/L) to CK within 4 h. In vitro studies demonstrated CK's high cytocompatibility and potent anti‐aging effects, including suppression of reactive oxygen species ( via upregulation of superoxide dismutase, catalase, and glutathione peroxidase), enhanced collagen I, Ⅲ and elastin synthesis, and matrix metalloproteinase‐1 inhibition. These findings highlight CK as a promising candidate for anti‐wrinkle formulations, supported by the feasibility of scalable bioproduction.

We describes the development of a poly-lactic-coglycolic acid (PLGA) nanoparticle-based system for conjugation of targeting peptides to PLGA nanoparticles and delivery of the therapeutic gene SOX9 to damaged astrocytes in a mouse stroke model.

Abstract Sialic acid-binding immunoglobulin-like lectin (Siglec)-8 is a human cell surface protein expressed exclusively on eosinophils, mast cells, and basophils that, when engaged, induces eosinophil apoptosis and inhibits mast cell mediator release. This makes Siglec-8 a promising therapeutic target to treat diseases involving these cell types. However, preclinical studies of Siglec-8 targeting in vivo are lacking because this protein is only found in humans, apes, and some monkeys. Therefore, we have developed a mouse strain in which SIGLEC8 transcription is activated by Cre recombinase and have crossed this mouse with the eoCre mouse to achieve eosinophil-specific expression. We confirmed that Siglec-8 is expressed exclusively on the surface of mature eosinophils in multiple tissues at levels comparable to those on human blood eosinophils. Following ovalbumin sensitization and airway challenge, Siglec-8 knock-in mice generated a pattern of allergic lung inflammation indistinguishable from that of littermate controls, suggesting that Siglec-8 expression within the eosinophil compartment does not alter allergic eosinophilic inflammation. Using bone marrow from these mice, we demonstrated that, during maturation, Siglec-8 expression occurs well before the late eosinophil developmental marker C-C motif chemokine receptor 3, consistent with eoCre expression. Antibody ligation of the receptor induces Siglec-8 endocytosis and alters the phosphotyrosine profile of these cells, indicative of productive signaling. Finally, we demonstrated that mouse eosinophils expressing Siglec-8 undergo cell death when the receptor is engaged, further evidence that Siglec-8 is functional on these cells. These mice should prove useful to investigate Siglec-8 biology and targeting in vivo in a variety of eosinophilic disease models. We have developed a novel eosinophil-specific Siglec-8 knock-in mouse strain that facilitates the in vivo study of Siglec-8 targeting and biology.