Glycyrrhizin administration ameliorates coxsackievirus B3-induced myocarditis in mice

Pentacyclic triterpenes, potential novel therapeutic approaches for cardiovascular diseases

Cardiovascular diseases (CVDs) involve dysfunction of the heart and blood vessels and have become major health concerns worldwide. Multiple mechanisms may be involved in the occurrence and development of CVDs. Although therapies for CVDs are constantly being developed and applied, the incidence and mortality of CVDs remain high. The roles of natural compounds in CVD treatment are being explored, providing new approaches for the treatment of CVD. Pentacyclic triterpenes are natural compounds with a basic nucleus of 30 carbon atoms, and they have been widely studied for their potential applications in the treatment of CVDs, to which various pharmacological activities contribute, including anti-inflammatory, antioxidant, and antitumor effects. This review introduces the roles of triterpenoids in the prevention and treatment of CVDs, summarizes their potential underlying mechanisms, and provides a comprehensive overview of the therapeutic potential of triterpenoids in the management of CVDs.

The State-of-the-Art Antibacterial Activities of Glycyrrhizin: A Comprehensive Review

Licorice (Glycyrrhiza glabra) is a plant of the genus Glycyrrhiza in the family Fabaceae/Leguminosae and is a renowned natural herb with a long history of medicinal use dating back to ancient times. Glycyrrhizin (GLY), the main active component of licorice, serves as a widely utilized therapeutic agent in clinical practice. GLY exhibits diverse medicinal properties, including anti-inflammatory, antibacterial, antiviral, antitumor, immunomodulatory, intestinal environment maintenance, and liver protection effects. However, current research primarily emphasizes GLY's antiviral activity, while providing limited insight into its antibacterial properties. GLY demonstrates a broad spectrum of antibacterial activity via inhibiting the growth of bacteria by targeting bacterial enzymes, impacting cell membrane formation, and altering membrane permeability. Moreover, GLY can also bolster host immunity by activating pertinent immune pathways, thereby enhancing pathogen clearance. This paper reviews GLY's inhibitory mechanisms against various pathogenic bacteria-induced pathological changes, its role as a high-mobility group box 1 inhibitor in immune regulation, and its efficacy in combating diseases caused by pathogenic bacteria. Furthermore, combining GLY with other antibiotics reduces the minimum inhibitory concentration, potentially aiding in the clinical development of combination therapies against drug-resistant bacteria. Sources of information were searched using PubMed, Web of Science, Science Direct, and GreenMedical for the keywords "licorice", "Glycyrrhizin", "antibacterial", "anti-inflammatory", "HMGB1", and combinations thereof, mainly from articles published from 1979 to 2024, with no language restrictions. Screening was carried out by one author and supplemented by others. Papers with experimental flaws in their experimental design and papers that did not meet expectations (antifungal papers, etc.) were excluded.

Natural products of pentacyclic triterpenoids: from discovery to heterologous biosynthesis

Covering: up to 2022Pentacyclic triterpenoids are important natural bioactive substances that are widely present in plants and fungi. They have significant medicinal efficacy, play an important role in reducing blood glucose and protecting the liver, and have anti-inflammatory, anti-oxidation, anti-fatigue, anti-viral, and anti-cancer activities. Pentacyclic triterpenoids are derived from the isoprenoid biosynthetic pathway, which generates common precursors of triterpenes and steroids, followed by cyclization with oxidosqualene cyclases (OSCs) and decoration via cytochrome P450 monooxygenases (CYP450s) and glycosyltransferases (GTs). Many biosynthetic pathways of triterpenoid saponins have been elucidated by studying their metabolic regulation network through the use of multiomics and identifying their functional genes. Unfortunately, natural resources of pentacyclic triterpenoids are limited due to their low content in plant tissues and the long growth cycle of plants. Based on the understanding of their biosynthetic pathway and transcriptional regulation, plant bioreactors and microbial cell factories are emerging as alternative means for the synthesis of desired triterpenoid saponins. The rapid development of synthetic biology, metabolic engineering, and fermentation technology has broadened channels for the accumulation of pentacyclic triterpenoid saponins. In this review, we summarize the classification, distribution, structural characteristics, and bioactivity of pentacyclic triterpenoids. We further discuss the biosynthetic pathways of pentacyclic triterpenoids and involved transcriptional regulation. Moreover, the recent progress and characteristics of heterologous biosynthesis in plants and microbial cell factories are discussed comparatively. Finally, we propose potential strategies to improve the accumulation of triterpenoid saponins, thereby providing a guide for their future biomanufacturing.

A Review of the Antiviral Activities of Glycyrrhizic Acid, Glycyrrhetinic Acid and Glycyrrhetinic Acid Monoglucuronide

Licorice, a natural medicine derived from the roots and rhizomes of Glycyrrhiza species, possesses a wide range of therapeutic applications, including antiviral properties. Glycyrrhizic acid (GL) and glycyrrhetinic acid (GA) are the most important active ingredients in licorice. Glycyrrhetinic acid 3-O-mono-β-d-glucuronide (GAMG) is the active metabolite of GL. GL and its metabolites have a wide range of antiviral activities against viruses, such as, the hepatitis virus, herpes virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and so on. Although their antiviral activity has been widely reported, the specific mechanism of action involving multiple links such as the virus itself, cells, and immunity are not clearly established. In this review, we will give an update on the role of GL and its metabolites as antiviral agents, and detail relevant evidence on the potential use and mechanisms of actions. Analyzing antivirals, their signaling, and the impacts of tissue and autoimmune protection may provide promising new therapeutic strategies.

Recent advances in glycyrrhizin metabolism, health benefits, clinical effects and drug delivery systems for efficacy improvement; a comprehensive review

BACKGROUND

Glycyrrhizin (GL) is a major active constituent of licorice root (Glycyrrhiza glabra) that is considered one of the oldest and most frequently employed botanicals in Chinese medicine and worldwide, with most effects attributed to its rich GL content. Structurally, GL a triterpene saponin that is widely used as a flavoring agent in foodstuffs and cosmetics, and also proposed for various clinical applications with a myriad of health benefits. Pharmacological and biological activities of GL include antiviral, anti-inflammatory, antioxidant, and anticancer activities (in vitro and in vivo). Currently, there is no comprehensive review on GL biological effects and its action mechanisms.

PURPOSE

This review summarizes GL pharmacological actions from a molecular biology perception, presented on its metabolism and side effects based on in vitro, in vitro and clinical studies. Moreover, the potential of GL as a nanomedicine delivery system is also summarized. The progress in drug delivery research using GL presented herein is expected to provide a theoretical basis for developing other novel drugs formulations.

METHODS

A systematic review was carried out in several electronic databases (Science Direct, SpringerLink, CNKI, PubMed, Web of Science, Elsevier, and Scopus), using the following key words: glycyrrhizin "AND" bioactivity "OR" clinic "OR" therapeutic "OR" drug delivery. This search included manuscripts published between 1989 and 2021.

RESULTS

126 researches were selected and summarized in this review. The analysis of these studies indicated that GL has antiviral activity against different viruses. Further, GL efficiently suppressed the respiratory manifestations associated with COVID-19 by reducing the expression of angiotensin converting enzyme 2 (ACE2) that employed by the virus as an entry point. Otherwise, GL was found to induce antioxidant, anti-inflammatory, immune-modulatory, and anticancer activity. Besides, diminution the particle size of GL to nanometer size significantly augments their action and biodistribution.

CONCLUSION

This article summarizes the pharmacological actions of GL. The potential of GL as a nanomedicine delivery system is also presented. Nevertheless, most studies reported provide no deep insight of GL health effects warranting for more future studies to elucidate its action mechanism and potential therapeutic benefits through preclinical and clinical trials.

Traditional Uses, Pharmacological Effects, and Molecular Mechanisms of Licorice in Potential Therapy of COVID-19

The current Coronavirus disease 2019 (COVID-19) pandemic has become a global challenge, and although vaccines have been developed, it is expected that mild to moderate patients will control their symptoms, especially in developing countries. Licorice, not only a food additive, but also a common traditional Chinese herbal medicine, which has several pharmacological effects, such as anti-inflammation, detoxification, antibacterial, antitussive, and immunomodulatory effects, especially in respiratory diseases. Since the outbreak of COVID-19, glycyrrhizin, glycyrrhizin diamine and glycyrrhizin extract have been widely studied and used in COVID-19 clinical trials. Therefore, it is a very interesting topic to explore the material basis, pharmacological characteristics and molecular mechanism of licorice in adjuvant treatment of COVID-19. In this paper, the material basis of licorice for the prevention and treatment of COVID-19 is deeply analyzed, and there are significant differences among different components in different pharmacological mechanisms. Glycyrrhizin and glycyrrhetinic acid inhibit the synthesis of inflammatory factors and inflammatory mediators by blocking the binding of ACE 2 to virus spike protein, and exert antiviral and antibacterial effects. Immune cells are stimulated by multiple targets and pathways to interfere with the pathogenesis of COVID-19. Liquiritin can prevent and cure COVID-19 by simulating type I interferon. It is suggested that licorice can exert its therapeutic advantage through multi-components and multi-targets. To sum up, licorice has the potential to adjuvant prevent and treat COVID-19. It not only plays a significant role in anti-inflammation and anti-ACE-2, but also significantly improves the clinical symptoms of fever, dry cough and shortness of breath, suggesting that licorice is expected to be a candidate drug for adjuvant treatment of patients with early / mild COVID-19.

Licorice (Glycyrrhiza glabra) Extracts-Suitable Pharmacological Interventions for COVID-19? A Review

Even though vaccination has started against COVID-19, people should continue maintaining personal and social caution as it takes months or years to get everyone vaccinated, and we are not sure how long the vaccine remains efficacious. In order to contribute to the mitigation of COVID-19 symptoms, the pharmaceutical industry aims to develop antiviral drugs to inhibit the SARS-CoV-2 replication and produce anti-inflammatory medications that will inhibit the acute respiratory distress syndrome (ARDS), which is the primary cause of mortality among the COVID-19 patients. In reference to these tasks, this article considers the properties of a medicinal plant named licorice (Glycyrrhiza glabra), whose phytochemicals have shown both antiviral and anti-inflammatory tendencies through previous studies. All the literature was selected through extensive search in various databases such as google scholar, Scopus, the Web of Science, and PubMed. In addition to the antiviral and anti-inflammatory properties, one of the licorice components has an autophagy-enhancing mechanism that studies have suggested to be necessary for COVID-19 treatment. Based on reviewing relevant professional and historical literature regarding the medicinal properties of licorice, it is suggested that it may be worthwhile to conduct in vitro and in vivo studies, including clinical trials with glycyrrhizic and glycyrrhetinic acids together with other flavonoids found in licorice, as there is the potentiality to provide natural interventions against COVID-19 symptoms.

Effect of glycyrrhizic acid and 18β-glycyrrhetinic acid on the differentiation of human umbilical cord-mesenchymal stem cells into hepatocytes

BACKGROUND

End-stage liver disease is a global health complication with high prevalence and limited treatment options. Cell-based therapies using mesenchymal stem cells (MSCs) emerged as an alternative approach to support hepatic regeneration. In vitro preconditioning strategies have been employed to strengthen the regenerative and differentiation potential of MSCs towards hepatic lineage. Chemical compounds of the triterpene class; glycyrrhizic acid (GA) and 18β-glycyrrhetinic acid (GT) possess diverse therapeutic properties including hepato-protection and anti-fibrosis characteristics. They are capable of modulating several signaling pathways that are crucial in hepatic regeneration. Preconditioning with hepato-protective triterpenes may stimulate MSC fate transition towards hepatocytes.

AIM

To explore the effect of GA and GT on hepatic differentiation of human umbilical cord-MSCs (hUC-MSCs).

METHODS

hUC-MSCs were isolated and characterized phenotypically by flow cytometry and immunocytochemistry for the expression of MSC-associated surface molecules. Isolated cells were treated with GA, GT, and their combination for 24 h and then analyzed at three time points; day 7, 14, and 21. qRT-PCR was performed for the expression of hepatic genes. Expression of hepatic proteins was analyzed by immunocytochemistry at day 21. Periodic acid Schiff staining was performed to determine the functional ability of treated cells.

RESULTS

The fusiform-shaped morphology of MSCs in the treatment groups in comparison with the untreated control, eventually progressed towards the polygonal morphology of hepatocytes with the passage of time. The temporal transcriptional profile of preconditioned MSCs displayed significant expression of hepatic genes with increasing time of differentiation. Preconditioned cells showed positive expression of hepatocyte-specific proteins. The results were further corroborated by positive periodic acid Schiff staining, indicating the presence of glycogen in their cytoplasm. Moreover, bi-nucleated cells, which is the typical feature of hepatocytes, were also seen in the preconditioned cells.

CONCLUSION

Preconditioning with glycyrrhizic acid, 18β-glycyrrhetinic acid and their combination, successfully differentiates hUC-MSCs into hepatic-like cells. These MSCs may serve as a better therapeutic option for degenerative liver diseases in future.

Saponins: Extraction, bio-medicinal properties and way forward to anti-viral representatives

Medicinal or herbal plants are widely used for their many favourable properties and are generally safe without any side effects. Saponins are sugar conjugated natural compounds which possess a multitude of biological activities such as medicinal properties, antimicrobial activity, antiviral activity, etc. Saponin production is a part of the normal growth and development process in a lot of plants and plant extracts such as liquorice and ginseng which are exploited as potential drug sources. Herbal compounds have shown a great potential against a wide variety of infectious agents, including viruses such as the SARS-CoV; these are all-natural products and do not show any adverse side effects. This article reviews the various aspects of saponin biosynthesis and extraction, the need for their integration into more mainstream medicinal therapies and how they could be potentially useful in treating viral diseases such as COVID-19, HIV, HSV, rotavirus etc. The literature presents a close review on the saponin efficacy in targeting mentioned viral diseases that occupy a high mortality rate worldwide. This manuscript indicates the role of saponins as a source of dynamic plant based anti-viral remedies and their various methods for extraction from different sources.

Traditional foods with their constituent's antiviral and immune system modulating properties

Background

Viruses are responsible for several diseases, including severe acute respiratory syndrome, a condition caused by today's pandemic coronavirus disease (COVID-19). A negotiated immune system is a common risk factor for all viral infections, including COVID-19. To date, no specific therapies or vaccines have been approved for coronavirus. In these circumstances, antiviral and immune boosting foods may ensure protection against viral infections, especially SARS-CoV-2 by reducing risk and ensuring fast healing of SARS-CoV-2 illness.

Scope and approach

In this review, we have conducted an online search using several search engines (Google Scholar, PubMed, Web of Science and Science Direct) to find out some traditional foods (plant, animal and fungi species), which have antiviral and immune-boosting properties against numerous viral infections, particularly coronaviruses (CoVs) and others RNA-virus infections. Our review indicated some foods to be considered as potential immune enhancers, which may help individuals to overcome viral infections like COVID-19 by modulating immune systems and reducing respiratory problems. Furthermore, this review will provide information regarding biological properties of conventional foods and their ingredients to uphold general health.

Key Findings and Conclusions

We observed some foods with antiviral and immune-boosting properties, which possess bioactive compounds that showed significant antiviral properties against different viruses, particularly RNA viruses such as CoVs. Interestingly, some antiviral and immune-boosting mechanisms were very much similar to the antiviral drug of COVID-19 homologous SARS (Severe Acute Respiratory Syndrome Coronavirus) and MERS (Middle East Respiratory Syndrome Coronavirus). The transient nature and the devastating spreading capability of COVID-19 lead to ineffectiveness of many curative therapies. Therefore, body shielding and immune-modulating foods, which have previous scientific recognition, have been discussed in this review to discern the efficacy of these foods against viral infections, especially SARS-CoV-2.

Exploring the Pivotal Immunomodulatory and Anti-Inflammatory Potentials of Glycyrrhizic and Glycyrrhetinic Acids

Licorice extract is a Chinese herbal medication most often used as a demulcent or elixir. The extract usually consists of many components but the key ingredients are glycyrrhizic (GL) and glycyrrhetinic acid (GA). GL and GA function as potent antioxidants, anti-inflammatory, antiviral, antitumor agents, and immuneregulators. GL and GA have potent activities against hepatitis A, B, and C viruses, human immunodeficiency virus type 1, vesicular stomatitis virus, herpes simplex virus, influenza A, severe acute respiratory syndrome-related coronavirus, respiratory syncytial virus, vaccinia virus, and arboviruses. Also, GA was observed to be of therapeutic valve in human enterovirus 71, which was recognized as the utmost regular virus responsible for hand, foot, and mouth disease. The anti-inflammatory mechanism of GL and GA is realized via cytokines like interferon-γ, tumor necrotizing factor-α, interleukin- (IL-) 1β, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, and IL-17. They also modulate anti-inflammatory mechanisms like intercellular cell adhesion molecule 1 and P-selectin, enzymes like inducible nitric oxide synthase (iNOS), and transcription factors such as nuclear factor-kappa B, signal transducer and activator of transcription- (STAT-) 3, and STAT-6. Furthermore, DCs treated with GL were capable of influencing T-cell differentiation toward Th1 subset. Moreover, GA is capable of blocking prostaglandin-E2 synthesis via blockade of cyclooxygenase- (COX-) 2 resulting in concurrent augmentation nitric oxide production through the enhancement of iNOS2 mRNA secretion in Leishmania-infected macrophages. GA is capable of inhibiting toll-like receptors as well as high-mobility group box 1.

Integrative role of traditional and modern technologies to combat COVID-19

INTRODUCTION

With the development of various branches of sciences, we will be able to resolve different clinical aspects of various diseases better. The convergence of these sciences can potentially tackle the new corona crisis.

AREAS COVERED

In this review, we attempted to explore and describe various scientific branches studying COVID-19. We have reviewed the literature focusing on the prevention, diagnosis, and treatment of COVID-19. The primary databases targeted were Science Direct, Scopus and PubMed. The most relevant reports from the recent two decades were collected utilizing keywords including SARS-CoV, MERS-CoV, COVID-19, epidemiology, therapeutics and diagnosis.

EXPERT OPINION

Based on this literature review, both traditional and emerging approaches are vital for the prevention, diagnosis and treatment of COVID-19. The traditional sciences play an essential role in the preventive and supportive care of corona infection, and modern technologies appear to be useful in the development of precise diagnosis and powerful treatment approaches for this disease. Indeed, the integration of these sciences will help us to fight COVID-19 disease more efficiently.

Battling COVID-19: using old weapons for a new enemy

Coronavirus disease-19 (COVID-19) has reached pandemic proportions. Most of the drugs that are being tried for the treatment have not been evaluated in any randomized controlled trials. The purpose of this review was to summarize the in-vitro and in-vivo efficacy of these drugs on Severe Acute Respiratory Syndrome (SARS-CoV-2) and related viruses (SARS and Middle East Respiratory Syndrome) and evaluate their potential for re-purposing them in the management of COVID-19.

Akt inhibitor deguelin aggravates inflammation and fibrosis in myocarditis

OBJECTIVES

Myocarditis is characterized by inflammatory cell infiltration in myocardial stroma. Attenuation of tumor necrosis factor (TNF)-α and interleukin (IL)-1β is a reliable mark for improving the prognosis. Protein kinase B (Akt) plays an important role in the development and progression of myocarditis. The specific role of the natural inhibitor of Akt, Deguelin, on myocarditis has not been reported. In this study, we used deguelin to investigate the effects of natural Akt inhibitor on myocarditis in experimental autoimmune myocarditis (EAM) rats.

MATERIALS AND METHODS

EAM rat models were made by using Lewis rats and Deguelin was injected intraperitoneally on day 3, 6, 9, 12 and 15 after successful modeling. On day 18, rats were sacrificed and the heart weight (HW)/ body weight (BW) ratio were measured. The pathological changes, pathological scores and fibrosis area were evaluated after H.&E. and Masson's trichrome staining. The mRNA levels of TNF-α and IL-1β were measured by RT-qPCR, while the protein expressions of TNF-α and IL-1β were detected by immunohistochemical staining and Western bolt. The protein expressions of Akt, Akt1, phosphorylated (p-) Akt and nuclear factor (NF)-κB were detected by Western bolt.

RESULTS

We found that the TNF-α and IL-1β levels, inflammatory scores and fibrosis areas were markedly increased after 18 days deguelin administration.

CONCLUSION

Akt inhibition with deguelin may aggravate myocarditis of EAM rats.

Research Progress of Glycyrrhizic Acid on Antiviral Activity

Glycyrrhizic acid (GA), a triterpene isolated from the roots and rhizomes of licorice, named Glycyrrhiza glabra, is the principal bioactive ingredient of anti-viral, anti-inflammatory and hepatoprotective effects. GA has been used in the clinical treatment of hepatitis, bronchitis, gastric ulcer, AIDS (acquired immunodeficiency syndrome), certain cancers and skin diseases. It has a direct effect on anti-HBV (hepatitis B virus) via affecting the HBsAg (hepatitis B surface antigen) to extracellular secretion, improving liver dysfunction in patients with chronic hepatitis B, and ultimately improving the immune status of HBV. GA can significantly inhibit the proliferation of HIV, showing an immune activation. The clinical application of GA on the prevention and treatments of various diseases may derive from its numerous pharmacological properties. This review provides the summary of the antiviral effects of GA on research progress and mechanism in recent years.

Effects of glycyrrhizin on lipopolysaccharide-induced acute lung injury in a mouse model

Background

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are serious clinical disease entities characterized by inflammatory pulmonary edema, which lead to acute hypoxic respiratory failure through various etiologies. According to the studies to date, ALI/ARDS has been recognized as a form of multiorgan failure related to overactive immune response, and overproduction of proinflammatory cytokines released from activated inflammatory cells are considered to play a key role in the development of ALI. Glycyrrhizin (GL) is an extractive component derived from Glycyrrhiza glabra (licorice), which has recently been reported to have various pharmacological effects like anti-inflammatory, anti-tumor, hepato-protective, and anti-viral activities. Nevertheless, the therapeutic effect of GL in ALI is still unclear. The aim of this study was to investigate therapeutic effects of GL on lipopolysaccharide (LPS)-induced ALI in a mouse model and to elucidate explicable mechanisms involved.

Methods

A total of 36 BALB/c mice (6-week-old, 27.7±1.9-gram body weight) were randomly divided into 3 groups: the control group (normal saline was administered intravenously, n=10), the LPS group (LPS 50 mg/kg was intraperitoneally administered, n=13), and the LPS + GL group (GL was administered intravenously immediately and 12 hours after LPS injection, n=13). Mice were sacrificed after 24 hours, and bronchoalveolar lavage fluid (BALF) was collected for the estimation of protein content, inflammatory cell counts, proinflammatory cytokines, myeloperoxidase (MPO) activity, and expressions of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and nuclear factor kappa B (NF-κB). Then, the lungs were excised for molecular target, histopathological, and immunohistochemical examinations.

Results

Compared to the LPS group, GL significantly decreased protein content, inflammatory cell counts, tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), IL-6, MPO activity, and expressions of COX-2, iNOS, and NF-κB in the LPS + GL group. GL attenuated migration and infiltration of inflammatory cells, showing a marked decrease in CD 11b-positive cells (26.77%±0.83% vs. 41.77%±0.81% vs. 23.23%±1.92%, P<0.05) as well as CXCR4-/CXCR1-positive cells (CXCR4: 37.23%±1.00% vs. 59.37%±2.37% vs. 47.45%±4.36%; CXCR1: 32.10%±1.56% vs. 47.03%±1.99% vs. 21.70%±6.50%; all P<0.05) in the control, LPS, and LPS + GL groups. Additionally, immunohistochemistry showed that the expression of Toll-like receptor 4 (TLR-4) was inhibited by GL.

Conclusions

The results of this study indicate that GL may have anti-inflammatory and protective effects on LPS-induced ALI in mice. GL inhibited proinflammatory cytokines playing a key role in the initial phase of inflammatory response, which suggests that inhibition of the TLR-4/NF-κB signal pathway would be a possible mechanism underlying the action of GL. Thus, GL can be used as a novel therapeutic strategy for pulmonary inflammation.

Glycyrrhizin administration ameliorates Streptococcus aureus-induced acute lung injury

Streptococcus aureus (S. aureus)-induced acute lung injury (ALI) has a high incidence of mortality clinically. Glycyrrhizin (GL) is a traditional Chinese medicine for anti-inflammatory. However, the role of GL in S. aureus-induced ALI has not previously been elucidated. GL (25 mg/kg i.p.) administration exerts potent anti-inflammatory effect in this model. GL administration significantly alleviated inflammation via reduction of multiple cytokines (serum and lung tissue IL-6, TNF-α, IL-8, IL-1β and HMGB1) and immune cells (lung tissue neutrophil and macrophage infiltration). Additionally, we measured the signaling pathways (NF-kB and MARKs) and inflammasome dependent pyroptosis. The results suggest that GL inhibits NF-kB, p38/ERK pathways and pyroptosis. Furthermore, we used different inhibitors to treat infected-A549 cells and found that BMS-582949 (a p38 inhibitor) is the most effective inhibitor for inhibiting pro-inflammatory cytokines (IL-6, TNF-α and IL-1β) production, which suggests that p38 signaling pathway might be the main pathway for S. aureus-induced inflammation. Collectively, the data demonstrates that GL could mitigate inflammation after S. aureus infection.

Liquorice (Glycyrrhiza glabra): A phytochemical and pharmacological review

In the last years, consumers are paying much more attention to natural medicines and principles, mainly due to the general sense that natural compounds are safe. On the other hand, there is a growing demand by industry for plants used in traditional medicine that could be incorporated in foods, nutraceuticals, cosmetics, or even pharmaceuticals. Glycyrrhiza glabra Linn. belongs to the Fabaceae family and has been recognized since ancient times for its ethnopharmacological values. This plant contains different phytocompounds, such as glycyrrhizin, 18β-glycyrrhetinic acid, glabrin A and B, and isoflavones, that have demonstrated various pharmacological activities. Pharmacological experiments have demonstrated that different extracts and pure compounds from this species exhibit a broad range of biological properties, including antibacterial, anti-inflammatory, antiviral, antioxidant, and antidiabetic activities. A few toxicological studies have reported some concerns. This review addresses all those issues and focuses on the pharmacological activities reported for G. glabra. Therefore, an updated, critical, and extensive overview on the current knowledge of G. glabra composition and biological activities is provided here in order to explore its therapeutic potential and future challenges to be utilized for the formulation of new products that will contribute to human well-being.

TRAF6: A player in CVB3-induced myocarditis?

Coxsackievirus B3 (CVB3) is an important inducer of myocarditis, which, in susceptible individuals, can chronify and eventually lead to the development of dilated cardiomyopathy and heart failure. The respective mechanisms are not completely understood. Here, we analyzed expression of the TRAF6 gene, encoding TNF receptor-associated factor 6 (TRAF6), a signal transduction scaffold protein that acts downstream of cytokine receptors, in heart tissue of susceptible and non-susceptible mouse strains. We found that after infection, TRAF6 expression was upregulated in both non-susceptible C57BL/6 wildtype and susceptible A.BY/SnJ and C57BL/6-TLR3 (-/-) mice, however, to different degrees. In infected HeLa cells, we also found moderately elevated TRAF6 levels after infection, in addition, activity of the transcription factor nuclear factor kappa B (NFκB), which can be activated downstream of TRAF6, was strongly enhanced in infected cells. To functionally analyze the role of TRAF6 with regard to infection progression, TRAF6 expression was knocked down in cultured HeLa cells using specific siRNAs. We found that reduction of TRAF6 expression had no effect on NFκB activation in response to infection. Taken together, our data suggest that CVB3 infection enhances TRAF6 levels, however, this induction might not be necessary for infection-induced NFκB activation.

Characteristics of Chinese herbal medicine usage in ischemic heart disease patients among type 2 diabetes and their protection against hydrogen peroxide-mediated apoptosis in H9C2 cardiomyoblasts

Evidence for long-term use of Chinese herbal medicine (CHM) as an adjuvant treatment in patients with type 2 diabetes (T2D) remains limited. This study aimed to assess the frequency of use, utilization patterns, and therapeutic effects of adjuvant CHM for ischemic heart disease (IHD) in patients with T2D in Taiwan. We identified 4620 IHD patients with T2D. After matching for age, gender, and insulin use, 988 subjects each were allocated to a CHM group and a non-CHM group. There were no differences in baseline characteristics except for comorbidities. The CHM group contained more cases with chronic obstructive pulmonary disease, hepatitis, ulcer disease, and hyperlipidemia. The cumulative survival probability was higher in CHM users than in matched non-CHM users aged 60 years or older (P < .0001, log rank test) regardless of gender (P = .0046 for men, P = .0010 for women, log rank test). Among the top 12 CHM combinations, Shu-Jing-Huo-Xue-Tang and Shao-Yao-Gan-Cao-Tang (13.6%) were the most common. This dual combination improved antiapoptotic activity in H₂O₂-exposed H9C2 cells by enhancing phosphorylation of glycogen synthase kinase-3β and p38 mitogen-activated protein kinase and could increase the survival of myocardial cells. Our study suggests that adjuvant CHM therapy may increase the survival probability and provides a comprehensive list for future investigations of the safety and efficacy of CHM for IHD patients with T2D.

Oleuropein prevents the development of experimental autoimmune myocarditis in rats

Oleuropein (OLE) is a natural secoiridoid that is derived from Olea europaea. OLE possesses cardioprotective effects in experimental models of hypertension, myocardial infarction, atherosclerosis and hyperlipidaemia. In the present study, the effects of OLE on experimental autoimmune myocarditis (EAM) were evaluated. EAM in rats were induced by subcutaneous injections of porcine cardiac myosin. Cardiac function parameters, myocardial pathology, myocardial inflammatory cell infiltration and nuclear factor kappa-B (NF-κB) expression were measured. Our data showed that the postmyocarditis rats exhibited increased left ventricular end systolic diameters, left ventricular end diastolic diameters, left ventricular end-diastolic pressures (LVEDP), and decreased ejection fractions. However, OLE significantly suppressed these changes in EAM rats. Histological analysis revealed that myosin induced miliary foci of discolouration on endocardial surfaces and extensive myocardial injuries with inflammatory cell infiltration were significantly improved by OLE therapy. A definitive positive correlation between the histological scores and LVEDP was observed. Moreover, OLE inhibited CD4⁺, CD8⁺ cells and macrophage infiltration in myocardium and decreased the serum production of tumour necrosis factor-a (TNF-a), interleukin-1β (IL-1β) and IL-6 in EAM rats. Expectedly, the myocardial levels of NF-κB p65, p-IκBa, IKKa were significantly attenuated by OLE, indicating the inhibitory effects of OLE on the NF-κB pathway. Furthermore, OLE decreased the myocardial expressions of phosphorylated-p38 MAPK, phosphorylated-ERK, and did not change the levels of p38 MAPK and ERK in EAM rats. Collectively, our results suggest that OLE effectively prevents the development of myocarditis, at least in part, by inhibiting the MAPKs and NF-κB mediated inflammatory responses.

[The effect of combination of glycyrrhizic acid with alpha-glutamyl-tryptophan on the experimental adenoviral infection]

In this work, the activity of glycyrrhizic acid (GL) and dipeptide alpha-glutamyl-tryptophane (EW) as single preparations or in combination (GL+EW) against experimental adenoviral infection in the syrian hamsters was studied. Application of gl and GL+EW was shown to decrease the level of the adenovirus replication in liver tissue by 0.6 - 1.2 lgTCID50 depending on the composition and time point of the post infection. It was also demonstrated that normalization of the structure of the liver tissue was required, which was shown on the level of both optical and electron microscopy. The results obtained in this work suggest that gl and GL+EW may be considered as potential component of the complex therapy of adenoviral infection.

The antiviral and antimicrobial activities of licorice, a widely-used Chinese herb

Licorice is a common herb which has been used in traditional Chinese medicine for centuries. More than 20 triterpenoids and nearly 300 flavonoids have been isolated from licorice. Recent studies have shown that these metabolites possess many pharmacological activities, such as antiviral, antimicrobial, anti-inflammatory, antitumor and other activities. This paper provides a summary of the antiviral and antimicrobial activities of licorice. The active components and the possible mechanisms for these activities are summarized in detail. This review will be helpful for the further studies of licorice for its potential therapeutic effects as an antiviral or an antimicrobial agent.

Glycyrrhizic acid in the treatment of liver diseases: literature review

Glycyrrhizic acid (GA) is a triterpene glycoside found in the roots of licorice plants (Glycyrrhiza glabra). GA is the most important active ingredient in the licorice root, and possesses a wide range of pharmacological and biological activities. GA coupled with glycyrrhetinic acid and 18-beta-glycyrrhetic acid was developed in China or Japan as an anti-inflammatory, antiviral, and antiallergic drug for liver disease. This review summarizes the current biological activities of GA and its medical applications in liver diseases. The pharmacological actions of GA include inhibition of hepatic apoptosis and necrosis; anti-inflammatory and immune regulatory actions; antiviral effects; and antitumor effects. This paper will be a useful reference for physicians and biologists researching GA and will open the door to novel agents in drug discovery and development from Chinese herbs. With additional research, GA may be more widely used in the treatment of liver diseases or other conditions.

Curcumin Protects Mice From Coxsackievirus B3-Induced Myocarditis by Inhibiting the Phosphatidylinositol 3 kinase/Akt/Nuclear Factor-κB Pathway

Viral myocarditis is an inflammation of the myocardium, and coxsackievirus B3 (CVB3) is one of the most important etiologic agents. Curcumin is an active ingredient of Curcumin longa, which has been used as a traditional Chinese herb for the treatment of various inflammatory diseases. The aim of this study was to explore the therapeutic effect of curcumin on CVB3-induced myocarditis and the underlying mechanism. Our results showed that treatment with curcumin could significantly attenuate CVB3-induced myocarditis, as demonstrated by improved weight loss, increased survival rate, reduced serological level cardiac enzymes, and improved heart histopathology. Of importance, curcumin administration was revealed to significantly reduce the systemic and local myocardial expression of proinflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL) 6, and IL-1β, in the CVB3-infected mice. Further study showed that curcumin treatment significantly inhibited the CVB3-induced activation of nuclear factor-κB (NF-κB), a key transcription factor in the pathogenesis of inflammation, in a phosphatidylinositol 3 kinase (PI3K)/Akt pathway-dependent manner. These data indicate that curcumin has protective effect against CVB3-induced myocarditis by inhibiting PI3K/Akt/NF-κB signaling pathway and thus reducing the inflammatory response.