Astragaloside IV ameliorates radiation-induced nerve cell damage by activating the BDNF/TrkB signaling pathway.

Radiation can induce nerve cell damage. Synapse connectivity and functionality are thought to be the essential foundation of all cognitive functions. Therefore, treating and preventing damage to synaptic structure and function is an urgent challenge. Astragaloside IV (AS-IV) is a glycoside extracted from Astragalus membranaceus (Fisch.). Bunge is a widely used traditional Chinese medicine in China with various pharmacological properties, including protective effects on the central nervous system (CNS). In this study, the effect of AS-IV on synapse damage and BDNF/TrkB signaling pathway in radiated C57BL/6 mice with X-rays was investigated. PC12 cells and primary cortical neurons were exposed to UVA in vitro. Open field test and rotarod test were used to observe the effects of AS-IV on the motor and explore the abilities of radiated mice. The pathological changes in the brain were observed by hematoxylin and eosin and Nissl staining. Immunofluorescence analysis was used to detect the synapse damage. The expressions of the BDNF/TrkB pathway and neuroprotection-related molecules were detected by Western blotting and Quantitative-RTPCR, respectively. The results showed that AS-IV could improve the motor and explore abilities of radiated mice, reduce pathological damage to the cortex, enhance neuroprotection functions, and activate BDNF/TrkB pathway. In conclusion, AS-IV could relieve radiation-induced synapse damage, at least partly through the BDNF/TrkB pathway.

Preliminary study on the anti-apoptotic mechanism of Astragaloside IV on radiation-induced brain cells.

With multiple targets and low cytotoxicity, natural medicines can be used as potential neuroprotective agents. The increase in oxidative stress levels and inflammatory responses in the brain caused by radiation affects cognitive function and neuronal structure, and ultimately leads to abnormal changes in neurogenesis, differentiation, and apoptosis. Astragaloside Ⅳ (AS-Ⅳ), one of the main active constituents of astragalus, is known for its antioxidant, antihypertensive, antidiabetic, anti-infarction, anti-inflammatory, anti-apoptotic and wound healing, angiogenesis, and other protective effects. In this study, the mechanism of AS-IV against radiation-induced apoptosis of brain cells in vitro and in vivo was explored by radiation modeling, which provided a theoretical basis for the development of anti-radiation Chinese herbal active molecules and brain health products. In order to study the protective mechanism of AS-IV on radiation-induced brain cell apoptosis in mice, the paper constructed a radiation-induced brain cell apoptosis model, using TUNEL staining, flow cytometry, Western blotting to analyze AS-IV resistance mechanism to radiation-induced brain cell apoptosis. The results of TUNEL staining and flow cytometry showed that the apoptosis rate of radiation group was significantly increased. The results of Western blotting indicated that the expression levels of p-JNK, p-p38, p53, Caspase-9 and Caspase-3 protein, and the ratio of Bax to Bcl-2 in radiation group were significantly increased. There was no significant difference in the expression levels of JNK and p38. After AS-IV treatment, the apoptosis was reduced and the expression of apoptosis related proteins was changed. These data suggested that AS-IV can effectively reduce radiation-induced apoptosis of brain cells, and its mechanism may be related to the phosphorylation regulation of JNK-p38.