Phosphorylation of Icariin Can Alleviate the Oxidative Stress Caused by the Duck Hepatitis Virus A through Mitogen-Activated Protein Kinases Signaling Pathways

The duck virus hepatitis (DVH) caused by the duck hepatitis virus A (DHAV) has produced extensive economic losses to the duck industry. The currently licensed commercial vaccine has shown some defects and does not completely prevent the DVH. Accordingly, a new alternative treatment for this disease is urgently needed. Previous studies have shown that icariin (ICA) and its phosphorylated derivative (pICA) possessed good anti-DHAV effects through direct and indirect antiviral pathways, such as antioxidative stress. But the antioxidant activity showed some differences between ICA and pICA. The aim of this study is to prove that ICA and pICA attenuate oxidative stress caused by DHAV in vitro and in vivo, and to investigate their mechanism of action to explain their differences in antioxidant activities. In vivo, the dynamic deaths, oxidative evaluation indexes and hepatic pathological change scores were detected. When was added the hinokitiol which showed the pro-oxidative effect as an intervention method, pICA still possessed more treatment effect than ICA. The strong correlation between mortality and oxidative stress proves that ICA and pICA alleviate oxidative stress caused by DHAV. This was also demonstrated by the addition of hydrogen peroxide (H2O2) as an intervention method in vitro. pICA can be more effective than ICA to improve duck embryonic hepatocytes (DEHs) viability and reduce the virulence of DHAV. The strong correlation between TCID50 and oxidative stress demonstrates that ICA and pICA can achieve anti-DHAV effects by inhibiting oxidative stress. In addition, the superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of ICA and pICA showed significant difference. pICA could significantly inhibit the phosphorylation of p38, extra cellular signal regulated Kinase (ERK 1/2) and c-Jun N-terminal kinase (JNK), which were related to mitogen-activated protein kinases (MAPKs) signaling pathways. Ultimately, compared to ICA, pICA exhibited more antioxidant activity that could regulate oxidative stress-related indicators, and inhibited the phosphorylation of MAPKs signaling pathway

Polysaccharides from Traditional Chinese Medicines: Extraction, Purification, Modification, and Biological Activity

Traditional Chinese Medicine (TCM) has been used to treat diseases in China for thousands of years. TCM compositions are complex, using as their various sources plants, animals, fungi, and minerals. Polysaccharides are one of the active and important ingredients of TCMs. Polysaccharides from TCMs exhibit a wide range of biological activities in terms of immunity- modifying, antiviral, anti-inflammatory, anti-oxidative, and anti-tumor properties. With their widespread biological activities, polysaccharides consistently attract scientist's interests, and the studies often concentrate on the extraction, purification, and biological activity of TCM polysaccharides. Currently, numerous studies have shown that the modification of polysaccharides can heighten or change the biological activities, which is a new angle of polysaccharide research. This review highlights the current knowledge of TCM polysaccharides, including their extraction, purification, modification, and biological activity, which will hopefully provide profound insights facilitating further research and development

Paneth cells in farm animals: current status and future direction

Abstract A healthy intestine plays an important role in the growth and development of farm animals. In small intestine, Paneth cells are well known for their regulation of intestinal microbiota and intestinal stem cells (ISCs). Although there has been a lot of studies and reviews on human and murine Paneth cells under intestinal homeostasis or disorders, little is known about Paneth cells in farm animals. Most farm animals possess Paneth cells in their small intestine, as identified by various staining methods, and Paneth cells of various livestock species exhibit noticeable differences in cell shape, granule number, and intestinal distribution. Paneth cells in farm animals and their antimicrobial peptides (AMPs) are susceptible to multiple factors such as dietary nutrients and intestinal infection. Thus, the comprehensive understanding of Paneth cells in different livestock species will contribute to the improvement of intestinal health. This review first summarizes the current status of Paneth cells in pig, cattle, sheep, horse, chicken and rabbit, and points out future directions for the investigation of Paneth cells in the reviewed animals

Anti-DHAV-1 reproduction and immuno-regulatory effects of a flavonoid prescription on duck virus hepatitis

Context: The flavonoid prescription baicalin-linarin-icariin-notoginsenoside R1 (BLIN) has a curative effect on duck virus hepatitis (DVH) caused by duck hepatitis A virus type 1 (DHAV-1). However, the mechanism of this curative effect is not understood. Objective: This study investigates the mechanism of the curative effect of BLIN on DVH caused by DHAV-1. We analyzed the anti-DHAV-1 reproduction mechanism and immuno-regulatory effect of BLIN. Materials and methods: The anti-DHAV-1 reproduction effects of BLIN at 20, 10, 5 and 2.5 μg/mL in vitro, as well as the influence of BLIN at 20 μg/mL on DHAV-1 adsorption, replication and release were tested using the qRT-PCR method. The promotion abilities of BLIN at 20, 10, 5 and 2.5 μg/mL on T- and B-lymphocyte proliferation were investigated by the MTT method. IL-2 and IFN-γ levels and total anti-DHAV-1 antibody secretion after treatment with DHAV-1 for 4, 8 and 54 h were determined by ELISA. Results: BLIN showed a dose-dependent DHAV-1 reproduction inhibitory effect. The inhibitory effect was highest at 20 μg/mL, where DHAV-1 adsorption and release were significantly lower. Meanwhile, BLIN at 5 μg/mL significantly increased T and B lymphocyte proliferation. BLIN stimulated total anti-DHAV-1 antibody secretion in ducklings at the dosage of 4 mg per duckling, but did not stimulate IL-2 and IFN-γ secretion significantly. Conclusions: BLIN inhibits DHAV-1 reproduction by suppressing its adsorption and release. Additionally, BLIN promoted the duckling antiviral response

Assessment of a Flavone-Polysaccharide Based Prescription for Treating Duck Virus Hepatitis.

Because polysaccharide and flavone ingredients display good antiviral activity, we developed a flavone/polysaccharide-containing prescription that would be effective against duck viral hepatitis (DVH) and investigated its hepatoprotective effects. Flavones were derived from Hypericum japonicum (HJF) (entire herb of Hypericum japonicum Thunb) and Salvia plebeia (SPF) (entire herb of Salvia plebeia R. Br.), and polysaccharides were derived from Radix Rehmanniae Recens (RRRP) (dried root of Rehmannia glutinosa Libosch). This prescription combination was based on the theory of syndrome differentiation and treatment in traditional Chinese veterinary medicine. In vitro and in vivo experiments were conducted using the three single ingredients compared to the combined HRS prescription to determine their anti-duck hepatitis A viral (anti-DHAV) activity. The results showed that all experimental conditions displayed anti-DHAV activity, but the HRS prescription presented the best effect. To further investigate the hepatoprotective effect of the HRS prescription on DHAV-induced hepatic injury, we tested the mortality rate, the hepatic pathological severity score, plasma biochemical indexes of hepatic function, blood DHAV gene expression levels and peroxidation damage evaluation indexes and then analyzed correlations among these indexes. The results demonstrated that the HRS prescription significantly decreased the mortality rate, reduced the severity of hepatic injury, decreased the hepatic pathological severity score, depressed blood DHAV gene expression levels, and returned the indexes of hepatic function and peroxidation almost to a normal level. These results indicate that the HRS prescription confers an outstanding hepatoprotective effect, and we expect that it will be developed into a new candidate anti-DHAV drug

A flavone-polysaccharide based prescription attenuates the mitochondrial dysfunction induced by duck hepatitis A virus type 1.

The principal target organ of duck hepatitis A virus type 1 (DHAV-1) is duckling liver, which is an energy-intensive organ and plays important roles in body's energy metabolism and conversion. As the "power house" of the hepatocytes, mitochondria provide more than 90% of the energy. However, mitochondria are much vulnerable to the oxidative stress for their rich in polyunsaturated fatty acids. Although previous researches have demonstrated that DHAV-1 could induce the oxidative stress in the serum of the infected ducklings, no related study on the mitochondria during the pathological process of DVH has been reported by far. To address this issue, we examined the HE stained tissue pathological slices, detected the hepatic SOD, CAT and GPX activities and MDA contents and analyzed the ATP content, mitochondrial ultrastructure and the mitochondrial SOD, GPX activities and MDA content in the liver tissues. The results showed that the hepatic redox status was significantly disturbed so that causing the mitochondrial dysfunction, ATP depletion and mitochondrial oxidative stress during the process of the DHAV-1 infection, and a prescription formulated with Hypericum japonicum flavone, Radix Rehmanniae Recens polysaccharide and Salvia plebeia flavone (HRS), which had been demonstrated with good anti-oxidative activity in serum, could effectively alleviate the hepatic injury and the oxidative stress in liver tissue induced by DHAV-1 thus alleviating the mitochondrial injury and oxidative stress. In a word, this research discovers the oxidative stress induced mitochondrial dysfunction and oxidative stress during the DVH pathological process and demonstrates HRS exerts good anti-oxidative activity in liver tissue to protect mitochondria against reactive oxygen species (ROS)

Relative DHAV gene expression levels in each group.

<p>Viral gene expression level in the VC group at 4 hpi was set to 1. ^a-c Bars at the same time point without the same superscripts differ significantly (<i>p</i> < 0.05). hpi: hours post-injection.</p