Comparison of the anti-duck hepatitis A virus activities of phosphorylated and sulfated Astragalus polysaccharides

Abstract

Duck hepatitis A virus (DHAV) (Picornaviridae) causes an infectious disease in ducks which results in severe losses in duck industry. However, the proper antiviral supportive drugs for this disease have not been discovered. Polysaccharide is the main ingredient of Astragalus that has been demonstrated to directly and indirectly inhibit RNA of viruses replication. In this study, the antiviral activities of Astragalus polysaccharide (APS) and its derivatives against DHAV were evaluated and compared. APS was modified via the sodium trimetaphosphate and sodium tripolyphosphate (STMP-STPP) method and chlorosulfonic acid-pyridine method to obtain its phosphate (pAPS) and sulfate (sAPS), respectively. The infrared structures of APS, pAPS, and sAPS were analyzed with the potassium bromide disc method. Additionally, the antiviral activities were evaluated with the MTT ((4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) method in vitro and the artificial inoculation method in vivo. The clinical therapy effects were evaluated by mortality rate, liver function-related biochemical indicators, and visual changes in pathological anatomy. The anti-DHAV proliferation effects of APS, pAPS, and sAPS on the viral multiplication process in cell and blood were observed with the reverse transcription-polymerase chain reaction method. The results revealed that pAPS inhibited DHAV proliferation more efficiently in the entire process of viral multiplication than APS and sAPS. Moreover, only pAPS significantly improved the survival rate to 33.5% and reduced the DHAV particle titer in the blood as well as liver lesions in clinical trials. The results indicated that pAPS exhibited greater anti-DHAV activity than APS and sAPS both in vitro and in vivo.

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

“…APS, active ingredients extracted from Astragalus, possess a wide range of medicinal benefits, such as immunomodulatory [9][10][11], antioxidant [21], antidiabetic [22], antitumor [23], and anti-inflammatory . APS inhibits IBV production.…”

“…effects [24]. Recent studies have shown that APS have an antiviral effect on several viruses [9][10][11][12][13][14][15], suggesting that APS have the potential to be developed and used as antiviral drugs. Our group recently reported that APS could be used as an adjuvants in IBV vaccine preparations, and provide better protection against IBV by stimulating both humoral andcellular immunity [25].…”

“…Cytotoxicity was determined by using a Cell Counting Kit-8 (CCK8; Donjindo, Japan) according to the manufacturer's instructions. Briefly, the CEK cells were seeded into96-well culture plates, at a density of 1 × 10 4 cells/well, and incubated at 37°C in a 5% CO 2 incubator for 24 h. After washing with PBS, three times, APS at various concentrations (1,5,10,20,30, or 50 μg/mL) were added to the wells. The cells were then cultured for a further 48 h. Mock-treated cells served as controls.…”

“…Several reports have confirmed that traditional Chinese herbs effectively inhibit the replication of various viruses [6][7][8]. Astragalus polysaccharides (APS), isolated from a traditional Chinese medicinal herb, Astragalus mongholicus, have been widely used immunopotentiators [9][10][11]. Recently, several studies have shown that supplementation with APS can inhibit replication of several animal viruses, including H9N2 avian influenza virus [12], foot and mouth disease virus [13], Newcastle disease virus [14], and infectious bursal disease virus [15].…”

Astragalus diphtherites FENZL var. diphtherites and Astragalus gymnalopecias RECH. FIL’in gövde ve kök kısımlarından farklı çözücüler ile elde edilen özütlerin invitro antioksidan ve antimikrobiyal özelliklerinin belirlenmesi

“…Moreover Astragalus is known with its feature that protects the liver against to fibrosis. (Gui et al, 2006;Wang et al, 2016;Lai et al, 2017b).…”