Isofraxidin ameliorated influenza viral inflammation in rodents via inhibiting platelet aggregation

Effect of Haoqin Qingdan Tang on influenza A virus through the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway

OBJECTIVE

Influenza, a viral respiratory illness, leads to seasonal epidemics and occasional pandemics. Given the rising resistance and adverse reactions associated with anti-influenza drugs, Traditional Chinese Medicine (TCM) emerges as a promising approach to counteract the influenza virus. Specifically, Haoqin Qingdan Tang (HQQDT), a TCM formula, has been employed as an adjuvant treatment for influenza in China. However, the active compounds and underlying mechanisms of HQQDT remain unknown.

AIM

The aim of this study was to investigate HQQDT's antiviral and anti-inflammatory activities in both in vivo and in vitro, and further reveal its active ingredients and mechanism.

METHODS

In vivo and in vitro experiments were conducted to verify the antiviral and anti-inflammatory activities of HQQDT. Subsequently, the active ingredients and mechanism of HQQDT were explored through combining high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS) analysis and network pharmacology. Finally, the examinations of cell cytokines and signaling pathways aimed to elucidate the predicted mechanisms.

RESULTS

The results indicated that HQQDT exhibited inhibitory effects on influenza viruses A/PR/8/34 (H1N1), A/HK/1/68 (H3N2), and A/California/4/2009 (H1N1) in vitro. Furthermore, HQQDT enhanced the survival rate of influenza-infected mice, reduced the lung index and lung virus titer, and mitigated lung tissue damage in vivo. The proinflammatory cytokine expression levels upon influenza virus infection in PR8-induced A549 cells or mice were suppressed by HQQDT, including IL-6, IL-1β, CCL2, CCL4, IP-10, interferon β1 (IFN-β1), the interferon regulatory factor 3 (IRF3), and hemagglutinin (HA). Twenty-two active components of HQQDT against influenza were identified using HPLC-Q-TOF-MS analysis. Based on network pharmacological predictions, the JAK/STAT signaling pathway is considered the most relevant for HQQDT's action against influenza. Finally, western blot assays revealed that HQQDT regulated the protein level of the JAK/STAT signaling pathway in PR8-infected A549 cells and lung tissue.

CONCLUSION

These findings verified the antiviral and anti-inflammatory effects of HQQDT through JAK-STAT signaling pathway in influenza infections, laying the foundation for its further development.

The coumarin component isofraxidin targets the G-protein-coupled receptor S1PR1 to modulate IL-17 signaling and alleviate ulcerative colitis

OBJECTIVE

The increasing global prevalence of ulcerative colitis (UC) underscores the imperative to explore novel therapeutic approaches. Traditional Chinese medicine has historically shown potential in addressing this ailment. The current study aimed to elucidate the functional attributes and underlying mechanisms of isofraxidin, a coumarin derivative from Acanthopanax, in the context of UC.

METHODS

A murine model of dextran sodium sulfate (DSS)-induced UC was established, and we conducted a comprehensive assessment of the influence of isofraxidin on UC symptomatology, colonic histopathological manifestations, the inflammatory response, and apoptosis. The potential receptor of isofraxidin was initially identified through the Target database and molecular docking analysis. Subsequent in vivo and in vitro experiments were conducted to determine the effects of isofraxidin on the identified receptor and associated signaling pathways. Transfection was used to examine the receptor's role in the regulatory mechanism of isofraxidin.

RESULTS

Isofraxidin reduced UC symptoms and colonic histopathological impairments. Furthermore, isofraxidin ameliorated the DSS-induced inflammatory response and apoptosis in tissues. S1PR1 was identified as a target of isofraxidin and effectively suppressed activation of the IL-17 signaling pathway. Intriguingly, cellular experiments indicated that overexpression of S1PR1 counteracted the protective effect of isofraxidin.

DISCUSSION

In summary, our investigation revealed that isofraxidin could modulate S1PR1 and regulate the IL-17 signaling pathway, thus ameliorating DSS-induced UC. These findings establish a robust foundation for considering isofraxidin as a prospective therapeutic intervention to treat UC.

Plant-Derived Natural Compounds as an Emerging Antiviral in Combating COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a human virus that burst at Wuhan in China and spread quickly over the world, leading to millions of deaths globally. The journey of this deadly virus to different mutant strains is still ongoing. The plethora of drugs and vaccines have been tested to cope up this pandemic. The herbal plants and different spices have received great attention during pandemic, because of their anti-inflammatory, and immunomodulatory properties in treating viruses and their symptoms. Also, it has been shown that nano-formulation of phytochemicals has potential therapeutic effect against COVID-19. Furthermore, the plant derived compound nano-formulation specifically increases its antiviral property by enhancing its bioavailability, solubility, and target-specific delivery system. This review highlights the potentiality of herbal plants and their phytochemical against SARS-CoV-2 utilizing different mechanisms such as blocking the ACE-2 receptors, inhibiting the main proteases, binding spike proteins and reducing the cytokine storms.

A comprehensive review on the chemical constituents, sesquiterpenoid biosynthesis and biological activities of Sarcandra glabra

Sarcandra glabra (Thunb.) Nakai is a perennial evergreen herb categorised within the Sarcandra Gardner genus under the Chloranthaceae family. Indigenous to tropical and subtropical regions of East Asia and India, this species is extensively distributed across China, particularly in the southern regions (Sichuan, Yunnan, and Jiangxi). In addition to its high ornamental value, S. glabra has a rich history of use in traditional Chinese medicine, evident through its empirical prescriptions for various ailments like pneumonia, dysentery, fractures, bruises, numbness, amenorrhea, rheumatism, and other diseases. Besides, modern pharmacological studies have revealed various biological activities, such as antitumour, anti-bacterial, anti-viral anti-inflammatory and immunomodulatory effects. The diverse chemical constituents of S. glabra have fascinated natural product researchers since the 1900s. To date, over 400 compounds including terpenoids, coumarins, lignans, flavonoids, sterols, anthraquinones, organic acids, and organic esters have been isolated and characterised, some featuring unprecedented structures. This review comprehensively examines the current understanding of S. glabra's phytochemistry and pharmacology, with emphasis on the chemistry and biosynthesis of its unique chemotaxonomic marker, the lindenane-type sesquiterpenoids.

The efficacy and mechanism of salmeterol against influenza A virus in vitro and in vivo

Influenza A virus (IAV) is the most harmful pathogen to human beings among the various subtypes of influenza virus, which can lead to immune response, cause serious inflammation and damage to the lung. Salmeterol is a candidate compound with anti-IAV activity screened by virtual network proximity predication. In this paper, we further evaluated the pharmacodynamics of salmeterol against IAV in vivo and in vitro. The results showed that salmeterol could inhibit the activity of three IAV strains (H1N1, H3N2 and H1N1 strain resistant to oseltamivir and amantadine) in the MDCK cells. In vivo, salmeterol could improve the survival state of infected mice, and further mechanism studies shown that salmeterol could improve the pathological characteristics of the lungs, reduce the loads of virus and the expression of M2 and IFITM3 proteins in the lungs of mice. In addition, salmeterol could inhibit the formation of NLRP3 inflammasome, thus reducing the production of the TNF-α, IL-6 and MCP-1 and alleviating inflammatory symptoms. Further results showed that salmeterol can protect A549 cells from cytopathic effect caused by IAV and reduce the production of inflammasome by decreasing the expression of RIG-1 in A549 cells. Finally, salmeterol could improve the spleen morphology and significantly increase the ratio of lymphocyte CD4⁺/CD8⁺ to improve immune function of infected mice. In our study, it is confirmed that salmeterol has certain anti-IAV activity through pharmacodynamic study in vivo and in vitro, which lays an important research foundation for the new indication of salmeterol and discovery of new drug against IAV.

Specialized metabolites from plants as a source of new multi-target antiviral drugs: a systematic review

Viral infections have always been the main global health challenge, as several potentially lethal viruses, including the hepatitis virus, herpes virus, and influenza virus, have affected human health for decades. Unfortunately, most licensed antiviral drugs are characterized by many adverse reactions and, in the long-term therapy, also develop viral resistance; for these reasons, researchers have focused their attention on investigating potential antiviral molecules from plants. Natural resources indeed offer a variety of specialized therapeutic metabolites that have been demonstrated to inhibit viral entry into the host cells and replication through the regulation of viral absorption, cell receptor binding, and competition for the activation of intracellular signaling pathways. Many active phytochemicals, including flavonoids, lignans, terpenoids, coumarins, saponins, alkaloids, etc., have been identified as potential candidates for preventing and treating viral infections. Using a systematic approach, this review summarises the knowledge obtained to date on the in vivo antiviral activity of specialized metabolites extracted from plant matrices by focusing on their mechanism of action.

Platelet caspase-1 and Bruton tyrosine kinase activation in patients with COVID-19 is associated with disease severity and reversed in vitro by ibrutinib

Background

Severity of coronavirus disease 2019 (COVID-19) is often associated with thrombotic complications and cytokine storm leading to intensive are unit (ICU) admission. Platelets are known to be responsible for abnormal hemostasis parameters (thrombocytopenia, raised D-dimers, and prolonged prothrombin time) in other viral infections through the activation of the nucleotide-binding domain leucine repeat rich containing protein 3 inflammasome induced by signaling pathways driven by Bruton tyrosine kinase (BTK) and leading to caspase-1 activation.

Objectives

We hypothesized that caspase-1 activation and the phosphorylation of BTK could be associated with the severity of the disease and that ibrutinib, a BTK inhibitor, could inhibit platelet activation.

Methods and Results

We studied caspase-1 activation by flow cytometry and the phosphorylation of BTK by Western blot in a cohort of 51 Afro-Carribean patients with COVID-19 disease (19 not treated in ICU and 32 treated in ICU). Patients with a platelet count of 286.7 × 10⁹/L (69-642 × 10⁹/L) were treated by steroids and heparin preventive anticoagulation. Caspase-1 and BTK activation were associated with the severity of the disease and with the procoagulant state of the patients. Furthermore, we showed in vitro that the plasma of ICU patients with COVID-19 was able to increase CD62P expression and caspase-1 activity of healthy platelets and that ibrutinib could prevent it.

Conclusions

Our results show that caspase-1 and BTK activation are related to disease severity and suggest the therapeutic hope raised by ibrutinib in the treatment of COVID-19 by reducing the procoagulant state of the patients.

Coumarins from Sarcandra glabra (Thunb.) Nakai and Acetylcholinesterase Inhibiting Activity

Nine coumarins including a pair of new enantiomers ( 1a / 1b ) and seven known compounds ( 2-8 ) were isolated from Sarcandra glabra (Thunb.) Nakai. Among them, compounds 1a and 1b were naturally occurring coumarin-phenylpropanoid conjugate enantiomers. Their structures were identified by NMR and ECD calculations. Compounds 1-8 were tested for acetylcholinesterase (AchE) inhibiting activity. The results of the enzymology experiment showed that compound 3 demonstrated obvious AchE inhibitory activity which showed an IC 50 value of 1.982 ± 0.003 μ M, and the binding sites were predicted by molecular docking.

Lignans from Mosla scabra Ameliorated Influenza A Virus-Induced Pneumonia via Inhibiting Macrophage Activation

The lower respiratory tract infection, induced by influenza virus, coronaviruses, and respiratory syncytial virus, remains a serious threat to human health that can cause a global pandemic. Thus, finding effective chemicals and therapeutic measures to advance the functional restoration of the respiratory tract after infection has been the emphasis of the studies on the subjects. Mosla scabra is a natural medicinal plant used for treating various lung and gastrointestinal diseases, including viral infection, cough, chronic obstructive pulmonary disease, acute gastroenteritis, and diarrhoea. In this study, the antiviral and anti-inflammatory effects of total lignans (MSTL) extracted from the plant were investigated in influenza A virus (IAV)-infected mice and RAW 264.7 macrophages. MSTL could not only protect the macrophages against IAV-induced pyroptosis but also could lighten the lung inflammation induced by IAV in vivo and in vitro. The network pharmacology analysis revealed that differentially expressed genes, mainly involving in EGFR tyrosine kinase inhibitor resistance, endocrine resistance, HIF-1 signaling pathway, C-type lectin receptor signaling pathway, and FOXO signaling pathway, contributed to the IAV-induced alveolar macrophage dysfunction. It indicated that MSTL enhanced the function of alveolar macrophages and improved IAV-induced lung injury in mice.

COVID-19, cytokines, inflammation, and spices: How are they related?

BACKGROUND

Cytokine storm is the exaggerated immune response often observed in viral infections. It is also intimately linked with the progression of COVID-19 disease as well as associated complications and mortality. Therefore, targeting the cytokine storm might help in reducing COVID-19-associated health complications. The number of COVID-19 associated deaths (as of January 15, 2021; https://www.worldometers.info/coronavirus/) in the USA is high (1199/million) as compared to countries like India (110/million). Although the reason behind this is not clear, spices may have some role in explaining this difference. Spices and herbs are used in different traditional medicines, especially in countries such as India to treat various chronic diseases due to their potent antioxidant and anti-inflammatory properties.

AIM

To evaluate the literature available on the anti-inflammatory properties of spices which might prove beneficial in the prevention and treatment of COVID-19 associated cytokine storm.

METHOD

A detailed literature search has been conducted on PubMed for collecting information pertaining to the COVID-19; the history, origin, key structural features, and mechanism of infection of SARS-CoV-2; the repurposed drugs in use for the management of COVID-19, and the anti-inflammatory role of spices to combat COVID-19 associated cytokine storm.

KEY FINDINGS

The literature search resulted in numerous in vitro, in vivo and clinical trials that have reported the potency of spices to exert anti-inflammatory effects by regulating crucial molecular targets for inflammation.

SIGNIFICANCE

As spices are derived from Mother Nature and are inexpensive, they are relatively safer to consume. Therefore, their anti-inflammatory property can be exploited to combat the cytokine storm in COVID-19 patients. This review thus focuses on the current knowledge on the role of spices for the treatment of COVID-19 through suppression of inflammation-linked cytokine storm.

A Biological Insight into the Susceptibility to Influenza Infection in Junior Rats by Comprehensive Analysis of lncRNA Profiles

Long noncoding RNAs (lncRNAs) have been reported to participate in regulating many biological processes, including immune response to influenza A virus (IAV). However, the association between lncRNA expression profiles and influenza infection susceptibility has not been well elucidated. Here, we analyzed the expression profiles of lncRNAs, miRNAs, and mRNAs among IAV-infected adult rat (IAR), normal adult rat (AR), IAV-infected junior rat (IJR), and normal junior rat (JR) by RNA sequencing. Compared with differently expressed lncRNAs (DElncRNAs) between AR and IAR, 24 specific DElncRNAs were found between IJR and JR. Then, based on the fold changes and P value, the top 5 DElncRNAs, including 3 upregulated and 2 downregulated lncRNAs, were chosen to establish a ceRNA network for further disclosing their regulatory mechanisms. To visualize the differentially expressed genes in the ceRNA network, GO and KEGG pathway analysis was performed to further explore their roles in influenza infection of junior rats. The results showed that the downregulated DElncRNA-target genes were mostly enriched in the IL-17 signaling pathway. It indicated that the downregulated lncRNAs conferred the susceptibility of junior rats to IAV via mediating the IL-17 signaling pathway.

Pimpinellin Inhibits Collagen-induced Platelet Aggregation and Activation Through Inhibiting Granule Secretion and PI3K/Akt Pathway

Pimpinellin is a coumarin-like compound extracted from the root of Toddalia asiatica. Its effects on platelet function has not been investigated. This study found that pimpinellin pretreatment effectively inhibited collagen-induced platelet aggregation, but did not alter ADP- and thrombin-induced aggregation. Platelets pretreated with pimpinellin showed reduced α granule (CD62) level and secretion of dense granule (ATP release). Pimpinellin-treated platelets also exhibited decreased clot reaction and TxB2 production. Pimpinellin pretreatment suppressed adhesion and spreading of human platelets on the fibrinogen coated surface. Analysis of tail bleeding time of mice administered with pimpinellin (40 mg/kg) revealed that pimpinellin did not change tail bleeding time significantly, number of blood cells, and APTT and PT levels. Pimpinellin inhibited collagen-induced ex vivo aggregation of mice platelets. Immunoblotting results showed that pimpinellin suppressed collagen-induced phosphorylation of PI3K-Akt-Gsk3β and PKC/MAPK in platelets.

The Traditional Uses, Phytochemistry and Pharmacology of Sarcandra glabra (Thunb.) Nakai, a Chinese Herb With Potential for Development: Review

Sarcandra glabra (Thunb.) Nakai is a folk medicine with a long history in China, which has been applied to treat sore throat, abscess, even tumor and so on. Meanwhile, it is also used as tea in some areas. At present, more than 200 chemical compounds have been isolated and identified from it, such as, sesquiterpenes, flavonoids, phenolic acids, coumarins and so on. Pharmacological studies have already confirmed that the extracts of S. glabra have many effects, such as antibacterial, antiviral, anti-inflammatory, anti-tumor, and anti-thrombocytopenia, especially the effects of anti-tumor and anti-thrombocytopenia are confirmed in clinic. Therefore, this paper systematically summarized the traditional uses, botany, phytochemistry, pharmacology, and toxicity of S. glabra, in order to provide a beneficial reference of its further research.

Isofraxidin Inhibits Receptor Activator of Nuclear Factor-κB Ligand-Induced Osteoclastogenesis in Bone Marrow-Derived Macrophages Isolated from Sprague-Dawley Rats by Regulating NF-κB/NFATc1 and Akt/NFATc1 Signaling Pathways

Osteoporosis is a common bone disease that is characterized by decreased bone mass and fragility fractures. Isofraxidin is a hydroxy coumarin with several biological and pharmacological activities including an anti-osteoarthritis effect. However, the role of isofraxidin in osteoporosis has not yet been investigated. In the present study, we used receptor activator of nuclear factor-κB ligand (RANKL) to induce osteoclast formation in primary bone marrow macrophages (BMMs). Our results showed that RANKL treatment significantly increased tartrate-resistant acid phosphatase (TRAP) activity, as well as the expression of osteoclastogenesis-related markers including MMP-9, c-Src, and cathepsin K at both mRNA and protein levels; however, these effects were inhibited by isofraxidin in BMMs. In addition, luciferase reporter assay demonstrated that isofraxidin treatment suppressed the RANKL-induced an increase in nuclear factor of activated T-cells cytoplasmic 1 (NFATc1) transcriptional activity. Besides, the decreased expression level of IκBα and increased levels of p-p65, p-IκBα, and p-Akt in RANKL-induced BMMs were attenuated by isofraxidin. Moreover, NFATc1 overexpression rescued the anti-osteoclastogenic effect of isofraxidin with increased expression levels of MMP-9, c-Src, and cathepsin K. Taken together, these findings indicated that isofraxidin inhibited RANKL-induced osteoclast formation in BMMs via inhibiting the activation of NF-κB/NFATc1 and Akt/NFATc1 signaling pathways. Thus, isofraxidin might be a therapeutic agent for the treatment of osteoporosis.

Interactions of Influenza and SARS-CoV-2 with the Lung Endothelium: Similarities, Differences, and Implications for Therapy

Respiratory viruses such as influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are a constant threat to public health given their ability to cause global pandemics. Infection with either virus may lead to aberrant host responses, such as excessive immune cell recruitment and activation, dysregulated inflammation, and coagulopathy. These may contribute to the development of lung edema and respiratory failure. An increasing amount of evidence suggests that lung endothelial cells play a critical role in the pathogenesis of both viruses. In this review, we discuss how infection with influenza or SARS-CoV-2 may induce endothelial dysfunction. We compare the effects of infection of these two viruses, how they may contribute to pathogenesis, and discuss the implications for potential treatment. Understanding the differences between the effects of these two viruses on lung endothelial cells will provide important insight to guide the development of therapeutics.

Natural product derived phytochemicals in managing acute lung injury by multiple mechanisms

Acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS) as common life-threatening lung diseases with high mortality rates are mostly associated with acute and severe inflammation in lungs. With increasing in-depth studies of ALI/ARDS, significant breakthroughs have been made, however, there are still no effective pharmacological therapies for treatment of ALI/ARDS. Especially, the novel coronavirus pneumonia (COVID-19) is ravaging the globe, and causes severe respiratory distress syndrome. Therefore, developing new drugs for therapy of ALI/ARDS is in great demand, which might also be helpful for treatment of COVID-19. Natural compounds have always inspired drug development, and numerous natural products have shown potential therapeutic effects on ALI/ARDS. Therefore, this review focuses on the potential therapeutic effects of natural compounds on ALI and the underlying mechanisms. Overall, the review discusses 159 compounds and summarizes more than 400 references to present the protective effects of natural compounds against ALI and the underlying mechanism.

Phytochemicals: Potential Therapeutic Interventions Against Coronavirus-Associated Lung Injury

Since the outbreak of coronavirus disease 2019 (COVID-19) in December 2019, millions of people have been infected and died worldwide. However, no drug has been approved for the treatment of this disease and its complications, which urges the need for finding novel therapeutic agents to combat. Among the complications due to COVID-19, lung injury has attained special attention. Besides, phytochemicals have shown prominent anti-inflammatory effects and thus possess significant effects in reducing lung injury caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Also, the prevailing evidence reveales the antiviral effects of those phytochemicals, including anti-SARS-CoV activity, which could pave the road in providing suitable lead compounds in the treatment of COVID-19. In the present study, candidate phytochemicals and related mechanisms of action have been shown in the treatment/protection of lung injuries induced by various methods. In terms of pharmacological mechanism, phytochemicals have shown potential inhibitory effects on inflammatory and oxidative pathways/mediators, involved in the pathogenesis of lung injury during COVID-19 infection. Also, a brief overview of phytochemicals with anti-SARS-CoV-2 compounds has been presented.