Astragalus polysaccharides inhibit avian infectious bronchitis virus infection by regulating viral replication

Abstract

The avian coronavirus causes infectious bronchitis (IB), which is one of the most serious diseases affecting the avian industry worldwide. However, there are no effective strategies for controlling the IB virus (IBV) at present. Therefore, development of novel antiviral treatment strategies is urgently required. As reported, astragalus polysaccharides (APS) have potential antiviral effects against several viruses; however, the antiviral effect of APS against IBV remains unclear. In this study, we explored whether APS had the potential to inhibit IBV infectionby utilizing several in vitro experimental approaches. To this end, the effect of APS on the replication of IBV was examined in chicken embryo kidney (CEK) cells. Viral titers were calculated by using the plaque formation assay, and the cytotoxicity of APS was tested by utilizing a Cell Counting Kit-8 assay. The expression of viral mRNA and cytokine (IL-1β, IL-6, IL-8 and TNF-α) mRNA transcripts was determined by real-time quantitative RT-PCR(qRT-PCR). IBV titers in infected CEK cells treated with APS were significantly reduced in a dose-dependent manner, indicating that APS inhibited IBV replication in vitro. We also found that the decreased viral replication after APS treatment was associated with reduced mRNA levels of the cytokines IL-1B, IL-6, IL-8 and TNF-α. In conclusion, these results suggest that APS exhibit antiviral activities against IBV and it may represent a potential therapeutic agent for inhibiting the replication of IBV.

Fermented Astragalus in diet altered the composition of fecal microbiota in broiler chickens

“…The major flavonoids of Astragalus are 3-O-β- d -glucoside, 2′-hydroxy-3′,4′-dimethoxyisoflavane-7-O-β- d -glycoside, 7,3′-dihydroxy-4′-methoxyisoflavone, 7,3-dimer-capto-4,1-methoxyisoflavone, 3-dimercapto-7,4,1-methoxyisoflavone, and kumatakenin (Lv et al 2011 ; Xiao et al 2004 ). A recent study showed that crude extracts of Astragalus are anti-inflammatory (Kim et al 2013 ), anti-viral (Zhang et al 2018 ), immunostimulatory (Zhang et al 2017 ), promote growth performance (Li et al 2018 ) and affects fecal microbiota of young hens (Qiao et al 2018a ). In recent years, fermentation has become a powerful tool for producing biological materials, degrading macromolecular material into small molecules, reducing the side effects associated with herbs such as Aristolochia plants, and introducing medicinal effects through biological modification (Lin and Chiang.…”

Cellulase-Assisted Extraction, Characterization, and Bioactivity against Rheumatoid Arthritis of Astragalus Polysaccharides

“…Astragalus membranaceus is the main component of Fangji Huangqi decoction. Pharmacological studies have shown that APS, as the main ingredient of Astragalus membranaceus, has various therapeutic functions, such as immune regulation [20,21], anti-inflammation [7,22], antioxidation [23], antivirus [24,25], antibacterial [26], lowering blood sugar [27], and protecting the liver [28] and kidney [29]. Furthermore, it has been reported that APS could prevent RA progression [8,30].…”

Yixintongmai Inhibits Proliferation, Migration and Promotes Apoptosis of Vascular Smooth Muscle Cells Cultured with High Glucose

“…As a potent ROS scavenger, Salvia miltiorrhiza Bunge inhibited high glucose-induced oxidative stress, reduced the generation of ROS and mitochondrial depolarization (Sun, et al, 2018). Astragalus polysaccharide had antioxidant, antiviral activities and promoted pro-apoptosis (Zhang, et al, 2018). These may partially explain the mechanisms of anti-atherosclerotic effects of yixintongmai.…”