Assessment of the hepatocyte protective effects of gypenoside and its phosphorylated derivative against DHAV-1 infection on duck embryonic hepatocytes

Progress in phosphorylation of natural products

Natural medicines are a valuable resource for the development of new drugs. However, factors such as low solubility and poor bioavailability of certain constituents have hindered their efficacy and potential as pharmaceuticals. Structural modification of natural products has emerged as an important research area for drug development. Phosphorylation groups, as crucial endogenous active groups, have been extensively utilized for structural modification and development of new drugs based on natural molecules. Incorporating phosphate groups into natural molecules not only enhances their stability, bioavailability, and pharmacological properties, but also improves their biological activity by altering their charge, hydrogen bonding, and spatial structure. This review summarizes the phosphorylation mechanism, modification approaches, and biological activity enhancement of natural medicines. Notably, compounds such as polysaccharides, flavonoids, terpenoids, anthraquinones, and coumarins exhibit increased antioxidation, anticancer, antiviral, immune regulatory, Antiaging, enzyme inhibition, bacteriostasis, liver protection, and lipid-lowering effects following phosphorylation modification.

Anti-inflammatory, cardioprotective effect of gypenoside against isoproterenol-induced cardiac remodeling in rats via alteration of inflammation and gut microbiota

BACKGROUND

Myocardial infarction (MI), commonly referred to as a heart attack, occurs when the blood flow to a portion of the heart is blocked, causing damage to the heart muscle. In this study, we scrutinized the cardioprotective effect of gypenoside against the isoproterenol (ISO)-induced myocardial injury (MI) in the rats.

METHODS

Wistar rats were divided into four groups as follow: normal, gypenoside (10 mg/kg), ISO control, and ISO control treated with the gypenoside (2.5, 5, and 10 mg/kg). Various parameters were estimated such as infract size, hemodynamic, inflammatory, antioxidant, cardiac, cytokines, and apoptotic markers. We also estimated the gut microbiota in the faces of the experimental rats. Finally, heart tissue histopathology performed.

RESULT

Dose-dependent treatment of gypenoside significantly (P < 0.001) reduced the infracted size along with suppression of the heart weight and heart ratio along with enhance the body weight. Gypenoside treatment considerably altered the level of cardiac parameters, cardiac membrane stabilizing enzyme, hemodynamic parameters, antioxidant, lipid parameters, hepatic parameters, renal parameters, inflammatory cytokines, and mediators. Gypenoside significantly (P < 0.001) suppressed the level of apoptotic markers such as caspase-3, caspase-6, and caspase-9. Gypenoside significantly (P < 0.001) altered the relative abundance of unclassified bacteria, Tenericutes, Candidatus_Saccharibacteria, Verrucomicrobia, Actinobacteria, Bacteroidetes, Firmicutes and suppressed the ratio of F/B.

CONCLUSION

Gypenoside acts as a protective phytoconstituents against the ISO-induced myocardial infraction in the rats via alteration of gut microbiota, inflammatory, and oxidative stress.

Phosphorylated bush sophora root polysaccharides protect the liver in duck viral hepatitis by preserving mitochondrial function

In order to ascertain the mechanism underlying the therapeutic efficacy of Bush sophora root polysaccharides (BSRPS) and phosphorylated Bush sophora root polysaccharides (pBSRPS) in the treatment of in duck viral hepatitis (DVH), an investigation was conducted to assess the protective impact of BSRPS and pBSRPS against duck hepatitis A virus type 1 (DHAV-1) induced mitochondrial dysfunction both in vivo and vitro. The BSRPS underwent modification through the utilization of the sodium trimetaphosphate - sodium tripolyphosphate method, and was subsequently characterized though Fourier infrared spectroscopy and scanning electron microscopy. Following this, the degree of mitochondrial oxidative damage and dysfunction was described through the use of fluorescence probes and various antioxidative enzyme assay kits. Furthermore, the utilization of transmission electron microscopy facilitated the observation of alterations in the mitochondrial ultrastructure within the liver tissue. Our findings demonstrated that both BSRPS and pBSRPS effectively mitigated mitochondrial oxidative stress and conserved mitochondrial functionality, as evidenced by heightened antioxidant enzyme activity, augmented ATP production, and stabilized mitochondrial membrane potential. Meanwhile, the histological and biochemical examinations revealed that the administration of BSRPS and pBSRPS resulted in a reduction of focal necrosis and infiltration of inflammatory cells, thereby mitigating liver injury. Additionally, both BSRPS and pBSRPS exhibited the ability to maintain liver mitochondrial membrane integrity and enhance the survival rate of ducklings infected with DHAV-1. Notably, pBSRPS demonstrated superior performance in all aspects of mitochondrial function compared to BSRPS. The findings indicated that maintaining mitochondrial homeostasis is a crucial factor in DHAV-1 infections, and the administration of BSRPS and pBSRPS may mitigate mitochondrial dysfunction and safeguard liver function.

Cardioprotective Effect of Gynostemma pentaphyllum against Streptozotocin Induced Cardiac Toxicity in Rats via Alteration of AMPK/Nrf2/HO-1 Pathway

Gynostemma pentaphyllum (GP) is a plant commonly used in diabetic therapy in China. GP having potent antioxidant effect against various free radicals. The purpose of the current investigation to identify the cardioprotective effect of GP against streptozotocin (STZ)/ high fat diet (HFD) induced cardiac dysfunction in rats via alteration of AMPK/Nrf2/HO-1 pathway. Wistar rats were used for the current protocol. The rats were received the intraperitoneal injection of STZ and HFD to induce the cardiac remodelling. Blood glucose level, insulin and lipid parameters were estimated. Blood pressure and heart rate were also estimated. Cardiac parameters, antioxidant, cytokines, total protein and inflammatory mediators were analysed. The mRNA expression was detected using the RT-qPCR, respectively. GP significantly (p < 0.001) decreased the BGL and improved the insulin level. GP altered the ratio of heart/BW, liver/BW, and lung/BW. GP treatment significantly (p < 0.001) suppressed the heart rate and blood pressure (diastolic, systolic and mean pressure). GP significantly (p < 0.001) reduced the level of TC, LDL, TG, VLDL and increased the level of HDL. DCM induced rats received the GP administration exhibited reduction in the level of CK and LDH. GP significantly (p < 0.001) reduced the levels of MDA, hydrogen peroxide, peroxynitrite, ROS and increased the level of GSH, SOD, CAT and GPx. GP significantly (p < 0.001) reduced the levels of cytokines (TNF-α, IL-6, IL-1β) and inflammatory parameters (COX-2 and NFκB). GP significantly (p < 0.001) suppressed the NLRP3 and NF-κB expression. GP also boosted mitochondrial biogenesis by boosting the PGC-1α, HO-1 and Nrf2 expression in cardiac tissue. GP treatment showed the cardioprotective effects against STZ induced diabetic cardiac dysfunction via alteration of AMPK/Nrf2/HO-1 pathway.

Protection of Ducklings from Duck Hepatitis A Virus Infection with ELPylated Duck Interferon-α

Duck viral hepatitis type I (DVH I) is a lethal disease in ducklings caused by duck hepatitis A virus (DHAV). Although the commercial vaccine is available for vaccination of one-day-old ducklings or breeder ducks, the disease is still prevalent due to the delayed immune response in ducklings and variable maternal antibody levels in breeder duck flocks. To explore the feasibility of duck interferon-α (DuIFN-α) for control of DVH I, DuIFN-α was expressed as an elastin-like polypeptide (ELP) fusion protein (ELP-DuIFN-α) in E. coli and purified by inverse phase transition cycling (ITC). After detection of its cytotoxicity, bioactivity, plasma stability and serum half-life, the protective efficacy of ELP-DuIFN-α against DHAV-1 infection of embryos or ducklings was evaluated using different treatment routes at different infection times. The results show that ELP-DuIFN-α was correctly expressed and purified to more than 90% purity after two cycles of ITC. The purified fusion protein had a specific anti-DHAV-1 activity of 6.0 × 104 IU/mg protein, significantly extended plasma stability and serum half-life without overt cytotoxicity. After allantoic injection with ELP-DuIFN-α pre-infection, co-infection or post-infection with DHAV-1, 5/5, 5/5 or 4/5 embryos survived from the virus challenge. After intramuscular injection or oral administration with ELP-DuIFN-α, 3/5 or 4/5 ducklings survived from co-infection with DHAV-1. After oral administration with ELP-DuIFN-α pre-infection, co-infection or post-infection with DHAV-1, 3/5, 4/5 or 4/5 ducklings survived from the virus challenge, and the relative transcription levels of interferon-stimulated genes were significantly higher than the normal control group and virus challenge control group (p < 0.01). These experimental data suggest that ELP-DuIFN-α can be used as a long-lasting anti-DHAV-1 reagent.

Analysis of Serum Biochemical Indexes, Egg Quality, and Liver Transcriptome in Laying Hens Fed Diets Supplemented with Gynostemma pentaphyllum Powder

Gynostemma pentaphyllum (GP), known as “southern ginseng”, can reduce the blood pressure and blood lipid levels. In this study, 300 layer chicks of one day old were divided randomly into three groups (control group (base diet), high addition group (base diet with 1% GP), and low addition group (base diet with 0.5% GP)). After 29 weeks, the growth performance, egg quality, and serum index were determined. Additionally, liver mRNA was identified using RNA-seq to investigate the molecular mechanisms. The results indicated that the serum total cholesterol and triglycerides decreased significantly in the GP addition group. The addition of GP increased the egg weight, Haugh unit and redness (a*) of the egg yolk color, and reduced the yolk cholesterol concentration. Moreover, 95 differentially expressed genes (DEGs) were screened between the control and GP addition group. GO and the KEGG analysis showed that the PPAR pathway was significantly enriched. Five fatty acid metabolism-related genes (FABP3, CYP7A1, ANKRD22, SCD1, and PCK1) were validated by qRT-PCR analysis, which confirmed the tendency of the expression. These DEGs in the PPAR pathway may be the key factors of GP affecting fatty acid metabolism. These results may provide a theoretical basis for further research and new insights into GP as a feed additive.

Gypenoside Inhibits Bovine Viral Diarrhea Virus Replication by Interfering with Viral Attachment and Internalization and Activating Apoptosis of Infected Cells

Bovine viral diarrhea virus (BVDV) causes a severe threat to the cattle industry due to ineffective control measures. Gypenoside is the primary component of Gynostemma pentaphyllum, which has potential medicinal value and has been widely applied as a food additive and herbal supplement. However, little is known about the antiviral effects of gypenoside. The present study aimed to explore the antiviral activities of gypenoside against BVDV infection. The inhibitory activity of gypenoside against BVDV was assessed by using virus titration and performing Western blotting, quantitative reverse transcription PCR (RT-qPCR), and immunofluorescence assays in MDBK cells. We found that gypenoside exhibited high anti-BVDV activity by interfering with the viral attachment to and internalization in cells. The study showed that BVDV infection inhibits apoptosis of infected cells from escaping the innate defense of host cells. Our data further demonstrated that gypenoside inhibited BVDV infection by electively activating the apoptosis of BVDV-infected cells for execution, as evidenced by the regulation of the expression of the apoptosis-related protein, promotion of caspase-3 activation, and display of positive TUNEL staining; no toxicity was observed in non-infected cells. Collectively, the data identified that gypenoside exerts an anti-BVDV-infection role by inhibiting viral attachment and internalization and selectively purging virally infected cells. Therefore, our study will contribute to the development of a novel prophylactic and therapeutic strategy against BVDV infection.

Triterpenoids from the genus Gynostemma: Chemistry and pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

G. pentaphyllum, also known as Jiao-Gu-Lan, has been used traditionally as folk remedies for many diseases, including diabetes mellitus, metabolic syndrome, aging, and neurodegenerative diseases in China and some countries in East and Southeast Asia. It is considered as an "immortality herb" in Guizhou Province, because it was consumed regularly by the elderly native inhabitants. Other species of the same genus Gynostemma such as G. longipes and G. laxum have been used as alternatives to G. pentaphyllum in ethno-medicine in Vietnam and other Asian countries.

AIM OF THE REVIEW

The review aims to summarize up-to-date study results on Gynostemma species, including traditional usage, phytochemical profile, pharmacological activities, and toxicological studies, in order to suggest future research orientation and therapeutic applications on acute and chronic diseases.

MATERIALS AND METHODS

The relevant literature on the genus Gynostemma was gathered from secondary databases (Web of Science and PubMed), books, and official websites. The latest literature cited in this review was published in February 2020.

RESULTS

The genus Gynostemma has been widely used in traditional medicine, mainly for treatment of diabetes, hypertension, obesity, and hepatosteatosis. To date, 328 dammarane-type saponins were isolated and structurally elucidated from Gynostemma species. Crude extracts, saponin-rich fractions (gypenosides), and pure compounds were reported to show a wide range of pharmacological activities in both in vitro and in vivo experiments. The most notable pharmacological effects were anti-cancer, cardioprotective, hepatoprotective, neuroprotective, anti-diabetic, anti-obesity, and anti-inflammatory activities. Toxicological studies were conducted only on G. pentaphyllum, showing that the plant extracts were relatively safe in both acute and long-term toxicity experiments at the given dosage while no toxicological studies were reported for the other species.

CONCLUSIONS

The review summarizes current studies on traditional uses, phytochemistry, biological properties, and toxicology of medicinal Gynostemma species. Till now, the majority of publications still focused only on G. pentaphyllum. However, the promising preliminary data of other Gynostemma species indicated the research potential of this genus, both in phytochemical and pharmacological aspects. Furthermore, clinical data are required to evaluate the efficacy and undesired effects of crude extracts, standard saponin fractions, and pure compounds prepared from Gynostemma medicinal plants.

Mutations in VP0 and 2C Proteins of Duck Hepatitis A Virus Type 3 Attenuate Viral Infection and Virulence

Duck hepatitis A virus (DHAV) is prevalent worldwide and has caused significant economic losses. As the predominant serotype in China, DHAV-3 has become a major challenge to the local duck industry. Here the genetics and pathogenesis of a virulent DHAV-3 strain and its embryo-passaged strain were assessed. There were only two amino acid substitutions (Y164N in VP0 protein and L71I in 2C protein) introduced during the adaptation process. The pathogenicity of these strains was further evaluated in vivo. Clinical signs, gross pathology, and histopathological analysis showed that the embryo-passaged strain was attenuated. Meanwhile, the viral RNA loads were significantly lower in the liver tissues of the ducklings infected with the attenuated strain. As expected, infection with the virulent and attenuated strains led to the activation of different innate immune genes. We suspected that the loss of replication efficiency in ducklings was responsible for the attenuation phenotype of the embryo-passaged strain. In addition, different innate immune responses in the liver of ducklings were at least partly responsible for the differential infectivity phenotype. These findings provide new insights into the genetics and pathogenesis of DHAV-3, which may aid the development of new vaccines and the implementation of immunization strategies.