The Antioxidant Action of Astragali radix: Its Active Components and Molecular Basis.

Astragali radix is a traditional medicinal herb with a long history and wide application. It is frequently used in prescriptions with other medicinal materials to replenish Qi. According to the classics of traditional Chinese medicine, Astragali radix is attributed with properties such as Qi replenishing and surface solidifying, sore healing and muscle generating, and inducing diuresis to reduce edema. Modern pharmacological studies have demonstrated that some extracts and active ingredients in Astragali radix function as antioxidants. The polysaccharides, saponins, and flavonoids in Astragali radix offer beneficial effects in preventing and controlling diseases caused by oxidative stress. However, there is still a lack of comprehensive research on the effective components and molecular mechanisms through which Astragali radix exerts antioxidant activity. In this paper, we review the active components with antioxidant effects in Astragali radix; summarize the content, bioavailability, and antioxidant mechanisms; and offer a reference for the clinical application of Astragalus and the future development of novel antioxidants.

PECAM-1 drives ß-catenin-mediated EndMT via internalization in colon cancer with diabetes mellitus.

BACKGROUND: Diabetes mellitus (DM) is considered to be a risk factor in carcinogenesis and progression, although the biological mechanisms are not well understood. Here we demonstrate that platelet-endothelial cell adhesion molecule 1 (PECAM-1) internalization drives ß-catenin-mediated endothelial-mesenchymal transition (EndMT) to link DM to cancer. METHODS: The tumor microenvironment (TME) was investigated for differences between colon cancer with and without DM by mRNA-microarray analysis. The effect of DM on colon cancer was determined in clinical patients and animal models. Furthermore, EndMT, PECAM-1 and Akt/GSK-3ß/ß-catenin signaling were analyzed under high glucose (HG) and human colon cancer cell (HCCC) supernatant (SN) or coculture conditions by western and immunofluorescence tests. RESULTS: DM promoted the progression and EndMT occurrence of colon cancer (CC). Regarding the mechanism, DM induced PECAM-1 defection from the cytomembrane, internalization and subsequent accumulation around the cell nucleus in endothelial cells, which promoted ß-catenin entry into the nucleus, leading to EndMT occurrence in CC with DM. Additionally, Akt/GSK-3ß signaling was enhanced to inhibit the degradation of ß-catenin, which regulates the process of EndMT. CONCLUSIONS: PECAM-1 defects and/or internalization are key events for ß-catenin-mediated EndMT, which is significantly boosted by enhanced Akt/GSK-3ß signaling in the DM-associated TME. This contributes to the mechanism by which DM promotes the carcinogenesis and progression of CC. Video Abstract.