ANTIBIOSIS, CHRONIC PHARYNGITIS MITIGATION AND TOXICOLOGY OF ASTRAGALUS BHOTANENSISI

Abstract

Background and aim: In China, AB has been used for thousands of years and widely used to treat chronic pharyngitis (CP). However, there is no scientific evidence to confirm this therapeutic claim. Here, we investigated the effects of AB extract on antibiosis, chronic pharyngitis mitigation and toxicology. Materials and methods: Disk diffusion method was used to assess the antibacterial activities of AB on four bacterial strains. A rat model of CP induced by β-hemolytic streptococcus (HS) was used to evaluate the ability of AB against CP and its underlying mechanism. Mice were administrated AB, and the survival status, organ index and histopathology, blood routine and biochemistry were measured to evaluate the toxicity of AB. Results: AB inhibited the growth of HS, diplococcus pneumoniae, Staphyloccocus aureus, and Escherichia coli. AB decreased the levels of IL-1β, TNF-α, MCP-1, ICAM-1, CRP, 5-HT, PEG2, IL-6, COX-2, and LTC4 in serum. AB also reduced infiltration and diffusion of pharyngeal inflammatory cells. At the dose of 20 g/kg of AB, the levels of blood routine and biochemistry had not significant abnormality. Additionally, AB increased significantly the spleen index of mice, but the other organ indexes of mice and histopathology of organs were not significantly pathologically changed. Conclusion: AB alleviated HS-induced CP by inhibiting inflammatory response, which may be related to the regulation of TLR4/p38MAPK/NFкB pathway. The dose of 20 g/kg of AB did not exhibit toxicity in mice except the potential toxic to spleen, and may be the maximum tolerance of mice.