Dual regulatory effect of plant extracts of Forsythia suspense on RANTES and MCP-1 secretion in influenza A virus-infected human bronchial epithelial cells

Targeting chemokine-receptor mediated molecular signaling by ethnopharmacological approaches

ETHNOPHARMACOLOGICAL RELEVANCE

Infection and inflammation are critical to global human health status and the goal of current pharmacological interventions intends formulating medications/preventives as a measure to deal with this situation. Chemokines and their cognate receptors are major regulatory molecules in many of these ailments. Natural products have been a keen source to the drug development industry, every year contributing significantly to the growing list of FDA approved drugs. A multiverse of natural resource is employed as a part of curative regimen in folk/traditional/ethnomedicine which can be employed to discover, repurpose, and design potent medications for the diseases of clinical concern.

AIM OF THE STUDY

This review aims to systematically document the ethnopharmacologically active agents targeting the infectious-inflammatory diseases through the chemokine-receptor nexus.

MATERIALS AND METHODS

Articles related to chemokine/receptor modulating ethnopharmacological anti-inflammatory, anti-infectious natural sources, bioactive compounds, and formulations have been examined with special emphasis on women related diseases. The available literature has been thoroughly scrutinized for the application of traditional medicines in chemokine associated experimental methods, their regulatory outcomes, and pertinence to women's health wherever applicable. Moreover, the potential traditional regimens under clinical trials have been critically assessed.

RESULTS

A systematic and comprehensive review on the chemokine-receptor targeting ethnopharmaceutics from the available literature has been provided. The article discusses the implication of traditional medicine in the chemokine system dynamics in diverse infectious-inflammatory disorders such as cardiovascular diseases, allergic diseases, inflammatory diseases, neuroinflammation, and cancer. On this note, critical evaluation of the available data surfaced multiple diseases prevalent in women such as osteoporosis, rheumatoid arthritis, breast cancer, cervical cancer and urinary tract infection. Currently there is no available literature highlighting chemokine-receptor targeting using traditional medicinal approach from women's health perspective. Moreover, despite being potent in vitro and in vivo setups there remains a gap in clinical translation of these formulations, which needs to be strategically and scientifically addressed to pave the way for their successful industrial translation.

CONCLUSIONS

The review provides an optimistic global perspective towards the applicability of ethnopharmacology in chemokine-receptor regulated infectious and inflammatory diseases with special emphasis on ailments prevalent in women, consecutively addressing their current status of clinical translation and future directions.

Forsythoside A regulates autophagy and apoptosis through the AMPK/mTOR/ULK1 pathway and alleviates inflammatory damage in MAC-T cells

Dairy cow mastitis is the most common disease encountered in dairy farming. Lipopolysaccharides (LPS), among the major virulence-related factors produced by Escherichia coli, stimulate mammary gland inflammation and cause its damage, thereby affecting milk yield and quality. Forsythoside A (FTA) is among the main active components of forsythia. Recent pharmacological studies have demonstrated that FTA possesses anti-inflammatory, antiviral, antioxidant, and other biological activities. This study investigated the effects of the FTA-activated AMP-activated protein kinase (AMPK) signaling pathway on LPS-induced autophagy, apoptosis, and inflammatory damage in bovine mammary epithelial (MAC-T) cells. Cell activity was measured using the Cell Counting Kit 8. Moreover, real-time quantitative polymerase chain reaction and western blot analyses were used to detect expression levels of autophagic, apoptotic, and inflammatory factors, as well as those of oxidative stress-related genes and proteins. The annexin-FITC/PI assay and immunofluorescence assay were used to detect the apoptosis rate and LC3B expression, respectively. We found that FTA attenuated LPS-induced inhibition of MAC-T cell proliferation, reduced mRNA expression of related inflammatory factors, relieved oxidative stress, and exerted protective effects on MAC-T cells. Additionally, FTA activated autophagy, attenuated inhibition of autophagy flow, and inhibited apoptosis. Autophagy and apoptosis were mainly regulated through the AMPK/mTOR/ULK1 pathway. The aforementioned FTA-induced effects were inhibited by the administration of Compound C (CC; an AMPK inhibitor). Taken together, these results indicate that FTA can alleviate LPS-induced inflammation and oxidative stress in MAC-T cells, attenuate impairments in autophagy, and inhibit apoptosis. However, these effects were blocked by CC, which suggests that FTA inhibits LPS-induced autophagy, apoptosis, and inflammatory damage in MAC-T cells by activating the AMPK pathway.

Antiviral effect and mechanism of Phillyrin and its reformulated FS21 against influenza

Background

Influenza virus causes significant morbidity and mortality with pandemic threat. Oleaceae Fructus Forsythiae is a medicinal herb. This study aimed to investigate antiviral effect of Phillyrin, a purified bioactive compound from this herb, and its reformulated preparation FS21 against influenza and its mechanism.

Methods

Madin-Darby Canine Kidney (MDCK) cells were infected by one of six influenza viruses: five influenza A viruses (IAVs: three H1N1 and two H3N2) and one influenza B virus (IBV). Virus-induced cytopathic effects were observed and recorded under microscope. Viral replication and mRNA transcription were evaluated by quantitative polymerase chain reaction (qPCR) and protein expression by Western blot. Infectious virus production was assessed using TCID50 assay, and IC50 was calculated accordingly. Pretreatment and time-of-addition experiments with Phillyrin or FS21 added 1 h before or in early (0-3 h), mid (3-6 h), or late (6-9 h) stages of viral infection were performed to assess their antiviral effects. Mechanistic studies included hemagglutination and neuraminidase inhibition, viral binding and entry, endosomal acidification, and plasmid-based influenza RNA polymerase activity.

Results

Phillyrin and FS21 had potent antiviral effects against all six IAV and IBV in a dose-dependent manner. Mechanistic studies showed that both suppressed influenza viral RNA polymerase with no effect on virus-mediated hemagglutination inhibition, viral binding or entry, endosomal acidification, or neuraminidase activity.

Conclusions

Phillyrin and FS21 have broad and potent antiviral effects against influenza viruses with inhibition of viral RNA polymerase as the distinct antiviral mechanism.

Immunomodulatory and antiviral effects of Lycium barbarum glycopeptide on influenza a virus infection

Influenza is caused by a respiratory virus and has a major global impact on human health. Influenza A viruses in particular are highly pathogenic to humans and have caused multiple pandemics. An important consequence of infection is viral pneumonia, and with serious complications of excessive inflammation and tissue damage. Therefore, simultaneously reducing direct damage caused by virus infection and relieving indirect damage caused by excessive inflammation would be an effective treatment strategy. Lycium barbarum glycopeptide (LbGp) is a mixture of five highly branched polysaccharide-protein conjuncts (LbGp1-5) isolated from Lycium barbarum fruit. LbGp has pro-immune activity that is 1-2 orders of magnitude stronger than that of other plant polysaccharides. However, there are few reports on the immunomodulatory and antiviral activities of LbGp. In this study, we evaluated the antiviral and immunomodulatory effects of LbGp in vivo and in vitro and investigated its therapeutic effect on H1N1-induced viral pneumonia and mechanisms of action. In vitro, cytokine secretion, NF-κB p65 nuclear translocation, and CD86 mRNA expression in LPS-stimulated RAW264.7 cells were constrained by LbGp treatment. In A549 cells, LbGp can inhibit H1N1 infection by blocking virus attachment and entry action. In vivo experiments confirmed that administration of LbGp can effectively increase the survival rate, body weight and decrease the lung index of mice infected with H1N1. Compared to the model group, pulmonary histopathologic symptoms in lung sections of mice treated with LbGp were obviously alleviated. Further investigation revealed that the mechanism of LbGp in the treatment of H1N1-induced viral pneumonia includes reducing the viral load in lung, regulating the phenotype of pulmonary macrophages, and inhibiting excessive inflammation. In conclusion, LbGp exhibits potential curative effects against H1N1-induced viral pneumonia in mice, and these effects are associated with its good immuno-regulatory and antiviral activities.

Comparative Evaluation of Forsythiae Fructus From Different Harvest Seasons and Regions by HPLC/NIR Analysis and Anti-inflammatory and Antioxidant Assays

Forsythiae Fructus (FF), the dry fruit of Forsythia suspensa (Thunb.) Vahl, has a long history of use in traditional Chinese Medicine for its heat-clearing and detoxifying properties. It possesses clinical therapeutic effects and biological functions showing efficacy in handling different diseases. To investigate the FF differences in Henan, Shanxi, and Shaanxi in August and October, the surface morphology, mid-infrared and near-infrared spectrums, and HPLC were analyzed. Concurrently, the anti-inflammatory and antioxidant effects on LPS-induced J774A.1 cells were evaluated by western blot and RT-qPCR. The results showed that FF from different Harvest Seasons and Regions are provided with different microstructures and mid-infrared and near-infrared spectrums, and the levels of forsythiaside A and phillyrin of FF from Shanxi in August and phillygenin of FF from Shaanxi in August were the highest. Meanwhile, FF from Shanxi and Shaanxi in August markedly reduced the levels of inflammatory cytokines and mediators (TNF-α, IL-1β, NF-κB, and iNOS) and the protein expression levels of phosphorylated total IKKα/β and nuclear NF-κB. In August, SXFF and SAXFF also promoted the mRNA expression levels of HO-1 and NQO1 and the protein expression levels of HO-1 and nuclear Nrf2 and suppressed the protein expression levels of KEAP1. Spearman correlation analysis showed that phillygenin had a strong correlation with the protein expression on LPS-induced J774A.1 cells. In summary, our results showed that FF from harvest seasons and regions contributed to the distinct differences in microstructure, the mid-infrared and near-infrared spectrums, and compound content. More importantly, FF from Shanxi and Shaanxi in August showed marked anti-inflammatory and antioxidant activities, but with some differences, which may be because of different contents of phillygenin and phillyrin of lignans in FF.

Phillygenin inhibits the inflammation and apoptosis of pulmonary epithelial cells by activating PPARγ signaling via downregulation of MMP8

Acute lung injury (ALI) is often responsible for the high morbidity of critically ill patients. The present study aimed to investigate whether phillygenin (PHI) can inhibit inflammation and apoptosis of pulmonary epithelial cells by activating peroxisome proliferator-activated receptor γ (PPARγ) signaling. The in vitro model of ALI was established using lipopolysaccharide (LPS) and PHI was used to treat the LPS-induced cells. Cell viability was assessed using the MTT assay and the concentration levels of the inflammatory factors were detected by ELISA. Western blotting and reverse transcription-quantitative PCR were conducted to measure the expression levels of the inflammation- and apoptosis-associated proteins. The MMP8-overexpression plasmid was transfected into LPS-induced cells, which were treated with PHI treatment and the expression levels of PPARγ were detected via western blotting. PHI treatment suppressed the induction of inflammation and apoptosis of LPS-induced BEAS-2B cells. Furthermore, the expression levels of MMP8 in BEAS-2B cells induced by LPS were decreased following PHI treatment. Following transfection of the MMP8 overexpression plasmid into the LPS-induced BEAS-2B cells and subsequent treatment of these cells with PHI, the expression levels of PPARγ were decreased. In conclusion, it was shown that PHI inhibited the inflammation and apoptosis of pulmonary epithelial cells by activating PPARγ signaling via downregulating MMP8. These data may provide valuable information for future studies exploring the therapeutic effects of PHI for ALI.

Trinorlabdane diterpenoid alkaloids featuring an unprecedented skeleton with anti-inflammatory and anti-viral activities from Forsythia suspensa

Two unique trinorlabdane diterpenoid alkaloids, forsyqinlingines A (1) and B (2), were isolated from the ripe fruits of Forsythia suspensa. Their structures, including absolute stereochemical configurations, were fully elucidated from extensive spectroscopy experiments, single-crystal X-ray diffraction, and electronic circular dichroism (ECD). In addition, a plausible biosynthetic pathway for the formation of compounds 1 and 2 in Forsythia suspensa was also proposed. In vitro, the two C₁₇-labdane diterpenoid alkaloids exhibited anti-inflammatory activities by inhibiting the release of β-glucuronidase in rat polymorphonuclear leukocytes (PMNs), and antiviral activities against influenza A (H1N1) virus and respiratory syncytial virus (RSV).

Two unique trinorlabdane diterpenoid alkaloids, forsyqinlingines A (1) and B (2), were isolated from the ripe fruits of Forsythia suspensa, and found to show significant anti-inflammatory activities and anti-viral activities.

Insights into forsythia honeysuckle (Lianhuaqingwen) capsules: A Chinese herbal medicine repurposed for COVID-19 pandemic

Background

In December 2019, a novel coronavirus, SARS-CoV-2 caused a series of acute atypical respiratory diseases worldwide. However, there is still a lack of drugs with clear curative effects, and the clinical trial research of vaccines has not been completely finished.

Purpose

LH capsules are approved TCM patent medicine that are widely used for the treatment of respiratory tract infectious diseases caused by colds and flu. On April 12, 2020, LH capsules and granules were officially repurposed by the China Food and Drug Administration (CFDA) for patients with mild COVID-19 based on their safety and efficacy demonstrated through multicentre, randomized, controlled clinical trials. We hope to conduct a comprehensive review of it through modern pharmacy methods, and try to explain its possible mechanism.

Methods

Using the full names of LH capsules Lianhuaqingwen, Lianhua Qingwen andSARS-COV-2, COVID-19 as the keywords of the search terms, systemically search for existing related papers in various databases such as Web of Science and PubMed. And completed the collection of clinical data in ClinicalTrials.gov and Chinese Clinical Trial Registry. Last but not least, we have sorted out the anti-inflammatory and antiviral mechanisms of LH capsules through literature and Selleck.

Results

This review systematically sorted out the active ingredients in LH capsules. Furthermore, the related pharmacological and clinical trials of LH capsule on SARS-CoV-2, IAV and IBV were discussed in detail. Moreover, the present review provides the first summary of the potential molecular mechanism of specific substances in LH capsules involved in resistance to SARS-COV-2 infection and the inhibition of cytokine storm syndrome (CSS) caused by IL-6.

Conclusion

This review summarizes the available reports and evidence that support the use of LH capsules as potential drug candidates for the prevention and treatment of COVID-19. However, TCM exerts its effects through multiple targets and multiple pathways, and LH capsules are not an exception. Therefore, the relevant mechanisms need to be further improved and experimentally verified.

Forsythoside A inhibits adhesion and migration of monocytes to type II alveolar epithelial cells in lipopolysaccharide-induced acute lung injury through upregulating miR-124

Acute lung injury (ALI) is a severe disease for which effective drugs are still lacking at present. Forsythia suspensa is a traditional Chinese medicine commonly used to relieve respiratory symptoms in China, but its functional mechanisms remain unclear. Therefore, forsythoside A (FA), the active constituent of F. suspensa, was studied in the present study. Inflammation models of type II alveolar epithelial MLE-12 cells and BALB/c mice stimulated by lipopolysaccharide (LPS) were established to explore the effects of FA on ALI and the underlying mechanisms. We found that FA inhibited the production of monocyte chemoattractant protein-1 (MCP-1/CCL2) in LPS-stimulated MLE-12 cells in a dose-dependent manner. Moreover, FA decreased the adhesion and migration of monocytes to MLE-12 cells. Furthermore, miR-124 expression was upregulated after FA treatment. The luciferase report assay showed that miR-124 mimic reduced the activity of CCL2 in MLE-12 cells. However, the inhibitory effects of FA on CCL2 expression and monocyte adhesion and migration to MLE-12 cells were counteracted by treatment with a miR-124 inhibitor. Critically, FA ameliorated LPS-induced pathological damage, decreased the serum levels of tumor necrosis factor-α and interleukin-6, and inhibited CCL2 secretion and macrophage infiltration in lungs in ALI mice. Meanwhile, administration of miR-124 inhibitor attenuated the protective effects of FA. The present study suggests that FA attenuates LPS-induced adhesion and migration of monocytes to type II alveolar epithelial cells though upregulating miR-124, thereby inhibiting the expression of CCL2. These findings indicate that the potential application of FA is promising and that miR-124 mimics could also be used in the treatment of ALI.

Peucedanum ostruthium Inhibits E-Selectin and VCAM-1 Expression in Endothelial Cells through Interference with NF-κB Signaling

Twenty natural remedies traditionally used against different inflammatory diseases were probed for their potential to suppress the expression of the inflammatory markers E-selectin and VCAM-1 in a model system of IL-1 stimulated human umbilical vein endothelial cells (HUVEC). One third of the tested extracts showed in vitro inhibitory effects comparable to the positive control oxozeaenol, an inhibitor of TAK1. Among them, the extract derived from the roots and rhizomes of Peucedanum ostruthium (i.e., Radix Imperatoriae), also known as masterwort, showed a pronounced and dose-dependent inhibitory effect. Reporter gene analysis demonstrated that inhibition takes place on the transcriptional level and involves the transcription factor NF-κB. A more detailed analysis revealed that the P. ostruthium extract (PO) affected the phosphorylation, degradation, and resynthesis of IκBα, the activation of IKKs, and the nuclear translocation of the NF-κB subunit RelA. Strikingly, early effects on this pathway were less affected as compared to later ones, suggesting that PO may act on mechanism(s) that are downstream of nuclear translocation. As the majority of cognate NF-κB inhibitors affect upstream events such as IKK2, these findings could indicate the existence of targetable signaling events at later stages of NF-κB activation.

Characterization of lignans in Forsythiae Fructus and their metabolites in rats by ultra-performance liquid chromatography coupled time-of-flight mass spectrometry

Objectives

This study was designed to profile the chemical information of Forsythiae Fructus (FF) and investigate the in-vivo FF-related xenobiotics, especially for lignans.

Methods

Rats were oral administrated of FF and pinoresinol-4-O-glucoside, respectively. Blood and urine samples were collected after ingestion, and xenobiotics was profiled by an UPLC/Qtof MS method.

Key findings

A total of 19 lignans were identified or tentatively characterized in FF, and 63 lignan-related xenobiotics were found in rat plasma and urine after ingestion of FF. It was found that lignans could be transformed into metabolites by furan ring opening, hydrogenation, demethylation, dehydration and phase II reactions (sulfation and glucuronidation). The whole metabolic behaviour of bisepoxylignan was revealed by evaluating the metabolism of pinoresinol-4-O-glucoside in vivo. It was found that the configuration of C-8/C-8ʹ was retained after furan ring opening and metabolic reactions always occurred at position of C-3/C-4/C-5 or C-3ʹ/C-4ʹ/C-5ʹ. Additionally, other types components in FF and in vivo were also characterized.

Conclusions

This work revealed the in-vivo metabolism of FF, and reported the characteristic metabolic reactions of lignans for the first time. It was also provided the foundation for the further investigation on pharmacodynamic components of FF or TCMs containing FF.

Labdane diterpenoids from Forsythia suspensa with anti-inflammatory and anti-viral activities

Five previously undescribed labdane diterpenoids, named Forsypensins A-E, were isolated from the fruits of Forsythia suspensa. The structures and relative configurations of the compounds were elucidated via extensive spectroscopic methods, and their absolute configurations were fully confirmed by single crystal X-ray diffraction analyses using Cu Kα radiation and electronic circular dichroism data. The five labdane diterpenoids showed in vitro anti-inflammatory activity in rat polymorphonuclear leukocytes, inhibiting the rates of β-glucuronidase release by 43.6%-49.2% at concentrations of 10 μM. The compounds also had anti-viral activity against influenza A (H1N1) virus and respiratory syncytial virus (RSV), with IC₅₀ values in the range 21.8-27.4 μM, and EC₅₀ values in the range 10.5-15.4 μM, respectively.

Probing the degradation mechanism of forsythiaside A and simultaneous determination of three forsythiasides in Forsythia preparations by a single marker

Forsythiaside A is the major component of Forsythia suspensa. This study investigated the degradation mechanism of forsythiaside A. Eight degraded components including forsythiaside I, forsythiaside H, forsythiaside E, caffeic acid, suspensaside A, β-hydroxy forsythiaside I, β-hydroxy forsythiaside H, and β-hydroxy forsythiaside A were identified by using ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry. Then, the quantitative analysis of multi-components by a single-marker was performed with ultra-high performance liquid chromatography to simultaneously determine forsythiaside A, forsythiaside H, and forsythiaside I in Forsythia suspensa preparations. The result showed good linear relationships within 2.871-287.1, 0.231-23.1, and 0.983-98.3 μg/mL (r > 0.9998), with average recoveries of 97.7, 95.7, and 95.8% and relative standard deviations of 1.4, 2.4, and 1.8%, respectively. Using forsythiaside A as an internal reference, the relative retention values of forsythiaside H and forsythiaside I to forsythiaside A were calculated to be 0.89 and 0.61, respectively, and the relative correction factors were 0.816 and 0.799, respectively. The method for quantitative analysis of multi-components by a single-marker was applied to evaluate the overall quality of forsythia preparations. There was no significant difference in the measurement results of the method developed and the method of external standard.

Phytochemistry, pharmacology, quality control and future research of Forsythia suspensa (Thunb.) Vahl: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Forsythiae Fructus (called Lianqiao in Chinese), the fruit of Forsythia suspensa (Thunb.) Vahl, is utilized as a common traditional medicine in China, Japan and Korea. It is traditionally used to treat pyrexia, inflammation, gonorrhea, carbuncle and erysipelas. Depending on the different harvest time, Forsythiae Fructus can be classified into two forms, namely Qingqiao and Laoqiao. The greenish fruits that start to ripen are collected as Qingqiao, while the yellow fruits that are fully ripe are collected as Laoqiao. Both are applied to medical use. This review aims to provide a systematic summary of F. suspensa (Forsythia suspensa (Thunb.) Vahl) and to reveal the correlation between the traditional uses and pharmacological activities so as to offer inspiration for future research.

MATERIALS AND METHODS

All corresponding information about F. suspensa was searched by Scifinder and obtained from scientific databases including Springer, Science Direct, Wiley, Pubmed and China Knowledge Resource Integrated (CNKI). Local dissertations and books were searched as well.

RESULTS

According to classical Chinese herbal texts and Chinese Pharmacopoeia, Forsythiae Fructus dominantly displays heat-clearing and detoxifying effects in TCM prescriptions. In modern research, more than 230 compounds were separated and identified from F. suspensa. 211 Of them were isolated from fruits. Lignans and phenylethanoid glycosides are considered as the characteristic and active constituents of this herb, such as forsythiaside, phillyrin, rutin and phillygenin. They exhibited anti-inflammatory, antioxidant, antibacterial, anti-virus, anti-cancer and anti-allergy effects, etc. Currently, there is no report on the toxicity of Forsythiae Fructus, despite slight toxicity of forsythiaside reported in local publications. Compared to Laoqiao, Qingqiao contains higher levels of forsythiaside, forsythoside C, cornoside, rutin, phillyrin, gallic acid and chlorogenic acid and lower levels of rengyol, β-glucose and S-suspensaside methyl ether.

CONCLUSION

Heat-clearing actions of Forsythiae Fructus are based on the anti-inflammatory and antioxidant properties of lignans and phenylethanoid glycosides. Detoxifying effects attribute to the antibacterial, antiviral and anti-cancer activities of Forsythiae Fructus. And traditional Chinese medicine (TCM) characteristics of Forsythiae Fructus (bitter flavor, slightly cold nature and lung meridian) supported its strong anti-inflammatory effects. In addition, the remarkable anti-inflammatory and antioxidant capacities of Forsythiae Fructus contribute to its anti-cancer and neuroprotective activities. The higher proportion of lignans and phenylethanoid glycosides in Qingqiao than Laoqiao might explain the better antioxidant ability of Qingqiao and more frequent uses of Qingqiao in TCM prescriptions. For future research, more in vivo experiments and clinical studies are encouraged to further clarify the relation between traditional uses and modern applications. Regarding to Qingqiao and Laoqiao, they remain to be differentiated by all-round quality control methods, and the chemical compositions and clinical effects between them should be compared.

Forsythiae Fructus: A Review on its Phytochemistry, Quality Control, Pharmacology and Pharmacokinetics

Forsythiae Fructus, as a traditional Chinese medicine, has been widely used both as a single herb and in compound prescriptions in Asia, mainly due to its heat-clearing and detoxifying effects. Modern pharmacology has proved Forsythiae Fructus possesses various therapeutic effects, both in vitro and in vivo, such as anti-inflammatory, antibacterial and antiviral activities. Up to now, three hundred and twenty-one compounds have been identified and sensitive analytical methods have been established for its quality control. Recently, the pharmacokinetics of Forsythiae Fructus and its bioactive compounds have been reported, providing valuable information for its clinical application. Therefore, this systematic review focused on the newest scientific reports on Forsythiae Fructus and extensively summarizes its phytochemistry, pharmacology, pharmacokinetics and standardization procedures, especially the difference between the two applied types—unripe Forsythiae Fructus and ripe Forsythiae Fructus—in the hope of providing a helpful reference and guide for its clinical applications and further studies.

Forsythoside A Inhibits BVDV Replication via TRAF2-Dependent CD28-4-1BB Signaling in Bovine PBMCs

Bovine viral diarrhea virus (BVDV), the causative agent of bovine viral diarrhea/mucosal disease (BVD/MD), is an important pathogen of cattle and other wild animals throughout the world. BVDV infection typically leads to an impaired immune response in cattle. In the present study, we investigated the effect of Forsythoside A (FTA) on BVDV infection of bovine peripheral blood mononuclear cells (PBMCs). We found that Forsythoside A could not only promote proliferation of PBMCs and T cells activation but also inhibit the replication of BVDV as well as apoptosis induced by BVDV. FTA treatment could counteract the BVDV-induced overproduction of IFN-γ to maintain the immune homeostasis in bovine PBMCs. At same time, FTA can enhance the secretion of IL-2. What's more, BVDV promotes the expression of CD28, 4-1BB and TRAF-2, which can be modulated by FTA. Our data suggest that FTA protects PBMCs from BVDV infection possibly via TRAF2-dependent CD28-4-1BB signaling, which may activate PBMCs in response to BVDV infection. Therefore, this aids in the development of an effective adjuvant for vaccines against BVDV and other specific FTA-based therapies for preventing BVDV infection.

Protective effects of phillyrin against influenza A virus in vivo

Influenza A virus infection represents a great threat to public health. However, owing to side effects and the emergence of resistant virus strains, the use of currently available anti-influenza drugs may be limited. In order to identify novel anti-influenza drugs, we investigated the antiviral effects of phillyrin against influenza A virus infection in vivo. The mean survival time, lung index, viral titers, influenza hemagglutinin (HA) protein and serum cytokines levels, and histopathological changes in lung tissue were examined. Administration of phillyrin at a dose of 20 mg/kg/day for 3 days significantly prolonged the mean survival time, reduced the lung index, decreased the virus titers and interleukin-6 levels, reduced the expression of HA, and attenuated lung tissue damage in mice infected with influenza A virus. Taken together, these data showed that phillyrin had potential protective effects against infection caused by influenza A virus.

8-Prenylkaempferol Suppresses Influenza A Virus-Induced RANTES Production in A549 Cells via Blocking PI3K-Mediated Transcriptional Activation of NF-κB and IRF3

8-Prenylkaempferol (8-PK) is a prenylflavonoid isolated from Sophora flavescens, a Chinese herb with antiviral and anti-inflammatory properties. In this study, we investigated its effect on regulated activation, normal T cell expressed and secreted (RANTES) secretion by influenza A virus (H1N1)-infected A549 alveolar epithelial cells. Cell inoculation with H1N1 evoked a significant induction in RANTES accumulation accompanied with time-related increase in nuclear translocation of nuclear factor-κB (NF-κB) and interferon regulatory factor 3 (IRF-3), but showed no effect on c-Jun phosphorylation. 8-PK could significantly inhibit not only RANTES production but also NF-κB and IRF-3 nuclear translocation. We had proved that both NF-κB and IRF-3 participated in H1N1-induced RANTES production since NF-κB inhibitor pyrrolidinedithio carbamate (PDTC) and IRF-3 siRNA attenuated significantly RANTES accumulation. H1N1 inoculation also increased PI3K activity as well as Akt phosphorylation and such responsiveness were attenuated by 8-PK. In the presence of wortmannin, nuclear translocation of NF-κB and IRF3 as well as RANTES production by H1N1 infection were all reversed, demonstrating that PI3K-Akt pathway is essential for NF-κB- and IRF-3-mediated RANTES production in A549 cells. Furthermore, 8-PK but not wortmannin, prevented effectively H1N1-evoked IκB degradation. In conclusion, 8-PK might be an anti-inflammatory agent for suppressing influenza A virus-induced RANTES production acts by blocking PI3K-mediated transcriptional activation of NF-κB and IRF-3 and in part by interfering with IκB degradation which subsequently decreases NF-κB translocation.

Evodia rutaecarpa and Three Major Alkaloids Abrogate Influenza A Virus (H1N1)-Induced Chemokines Production and Cell Migration

Evodia rutaecarpa is commonly used as an anti-inflammatory herbal remedy in traditional Chinese medicine. In this study, the ethanol extract of E. rutaecarpa (ER) and three major quinazoline alkaloids dehydroevodiamine (DeHE), evodiamine (Evo) and rutaecarpine (Rut), isolated from ER were employed to study their inhibitory effects against influenza A virus (H1N1)-induced chemokines production in A549 lung epithelial cells as well as on chemokines-evoked cell recruitment in HL-60-differentiated macrophages. The results showed that ER was a potent inhibitor of RANTES secretion by H1N1-inoculated A549 cells (IC(50): 1.9 ± 0.4 μg ml(-1)). Three alkaloids, although to differing extents, all concentration dependent, inhibited H1N1-induced RANTES production with Evo consistently being the most potent among these active components. ER also moderately and significantly inhibited H1N1-stimulated MCP-1 production in A549 cells. This was mimicked by Evo and Rut, but not DeHE. In the macrophage recruitment assay, both RANTES and MCP-1 markedly evoked cell migration and this phenomenon was significantly suppressed by ER. Evo and Rut, but not DeHE, also had the ability to inhibit cell migration toward RANTES and MCP-1, respectively. In summary, three major alkaloids displayed different potentials for inhibiting chemokines secretion and subsequently cell migration, which could partially explain the activity of ER. As an effective agent to suppress H1N1-induced chemokines production and block chemokine-attracted leukocytes recruitment, E. rutaecarpa and its active components may be useful in influenza virus infection-related inflammatory disorders.

Pinoresinol from the fruits of Forsythia koreana inhibits inflammatory responses in LPS-activated microglia

The activation of microglia plays an important role in a variety of brain disorders by the excessive production of inflammatory mediators such as nitric oxide (NO), prostaglandin E(2) (PGE(2)) and proinflammatory cytokines. We investigated here whether pinoresinol isolated from the fruits of Forsythia koreana Nakai inhibits the inflammatory responses in LPS-activated microglia. Pinoresinol inhibited the production of NO, PGE(2), TNF-alpha, IL-1beta and IL-6 in LPS-activated primary microglia. Also, pinoresinol attenuated mRNA and protein levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and proinflammatory cytokines in LPS-activation. However, most of these inhibitory effects of pinoresinol have been mediated by extracellular-signal-regulated kinase (ERK) 1/2 mitogen-activated protein kinase (MAPK) phosphorylation and the NF-kappaB dependent. The results suggest that pinoresinol attenuates inflammatory responses of microglia and could be potentially useful in modulation of inflammatory status in brain disorders.

An LC-MS/MS method for determination of forsythiaside in rat plasma and application to a pharmacokinetic study

A highly sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the determination of forsythiaside in rat plasma using epicatechin as internal standard. The analytes were extracted by solid-phase extraction and chromatographied on a C(18) column eluted with a gradient mobile phase of acetonitrile and water both containing 0.2% formic acid. The detection was performed by negative ion electrospray ionization in multiple reaction monitoring mode, monitoring the transitions m/z 623-->161 and m/z 289-->109 for forsythiaside and epicatechin, respectively. The assay was linear over the concentration ranges of 2.0-50.0 and 50.0-5000.0ng/mL with limits of detection and quantification of 0.2 and 1.0ng/mL, respectively. The precision was <10.8% and the accuracy was >91.9%, and extraction recovery ranged from 81.3% to 85.0%. This method was successfully applied to a pharmacokinetic study of forsythiaside in rats after intravenous (20mg/kg) and oral (100mg/kg) administration, and the result showed that the compound was poorly absorbed with an absolute bioavailability being approximately 0.5%.