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

Efficient glycyrrhetinic acid biomanufacturing through protein engineering and dual-GUS combination strategy with novel β-glucuronidase from Aspergillus calidoustus CLH-22

Glycyrrhetinicacid (GA) is a high-value pentacyclic triterpenoid with broad applications. However, the industrial production of GA is hindered by low yield and the accumulation of the intermediate product GlycyrrhetinicAcid3-O-Mono-β-D-Glucuronide (GAMG). This study first identified a novel β-glucuronidase (AcGUS) from Aspergillus calidoustus CLH-22 through transcriptomic analysis, demonstrating a substrate preference for GAMG. Subsequently, mutant AcGUS3G461C/Q462H/I575K with significantly improved activity (kcat/Km of 11.02-fold) was obtained via computer-aided engineering. Furthermore, the dual-GUS combination strategy was employed for the first timeto construct engineered Pichia pastoris for GA production, offering multiple advantages of enhanced conversion efficiency and reduced fermentation viscosity. Finally, under systematically optimized conditions and employing Glycyrrhizin (GL) as the substrate, the final concentration of GA was 48.73 g/L with a conversion of 97.26 % in a 1000-L fermenter, representing the optimal biocatalytic performance reported to date. This study provides new ideas and insights for industrial GA production.

One-Step Organic Synthesis of 18β-Glycyrrhetinic Acid-Anthraquinone Ester Products: Exploration of Antibacterial Activity and Structure-Activity Relationship, Toxicity Evaluation in Zebrafish

To combine the activity characteristics of 18β-glycyrrhetinic acid (18β-GA) and anthraquinone compounds (rhein and emodin), reduce toxicity, and explore the structure-activity relationship (SAR) of anthraquinones, 18β-GA-anthraquinone ester compounds were synthesized by one-step organic synthesis. The products were separated and purified by HPLC and characterized by NMR and EI-MS. It was finally determined as di-18β-GA-3-rhein ester (1, New), GA dimer (2, known), 18β-GA-3-emodin ester (3, known), and di-18β-GA-1-emodin ester (4, new). The MIC of three reactants and four products against Escherichia coli and Staphylococcus aureus were detected in vitro. Its developmental toxicity and cardiotoxicity were assessed using zebrafish embryos. The experimental results showed that rhein had the best antibacterial activity against Staphylococcus aureus with MIC50 of 2.4 mM, and it was speculated that -COOH, -OH, and intramolecular hydrogen bonds in anthraquinone compounds would enhance the antibacterial effect, while the presence of-CH3 might weaken the antibacterial activity. Product 1 increased the hatching rate and survival rate of zebrafish embryos and reduced the malformation rate and cardiomyocyte apoptosis. This experiment lays the foundation for further studying the SAR of anthraquinones and providing new drug candidates.

Crosstalk between ROS-inflammatory gene expression axis in the progression of lung disorders

A significant number of deaths and disabilities worldwide are brought on by inflammatory lung diseases. Many inflammatory lung disorders, including chronic respiratory emphysema, resistant asthma, resistance to steroids, and coronavirus-infected lung infections, have severe variants for which there are no viable treatments; as a result, new treatment alternatives are needed. Here, we emphasize how oxidative imbalance contributes to the emergence of provocative lung problems that are challenging to treat. Endogenic antioxidant systems are not enough to avert free radical-mediated damage due to the induced overproduction of ROS. Pro-inflammatory mediators are then produced due to intracellular signaling events, which can harm the tissue and worsen the inflammatory response. Overproduction of ROS causes oxidative stress, which causes lung damage and various disease conditions. Invasive microorganisms or hazardous substances that are inhaled repeatedly can cause an excessive amount of ROS to be produced. By starting signal transduction pathways, increased ROS generation during inflammation may cause recurrent DNA damage and apoptosis and activate proto-oncogenes. This review provides information about new targets for conducting research in related domains or target factors to prevent, control, or treat such inflammatory oxidative stress-induced inflammatory lung disorders.

Bio-active metabolites from Chinese Medicinal Herbs for treatment of skin diseases

Skin diseases have become serious issues to human health and affect one-third of the world's population according to the World Health Organisation (WHO). These consist of internal (endogenous) and external (exogenous) factors referring to genetics, hormones, and the body's immune system, as well as environmental situations, UV radiation, or environmental pollution respectively. Generally, Western Medicines (WMs) are usually treated with topical creams or strong medications for skin diseases that help superficially, and often do not treat the root cause. The relief may be instant and strong, sometimes these medicines have adverse reactions that are too strong to be able and sustained over a long period, especially steroid drug type. Chinese Medicinal Herbs (CMHs) are natural resources and relatively mild in the treatment of both manifestation and the root cause of disease. Nowadays, CMHs are attractive to many scientists, especially in studying their formulations for the treatment of skin diseases.

METHODS

The methodology of this review was searched in nine electronic databases including WanFang Data, PubMed, Science Direct, Scopus, Web of Science, Springer Link, SciFinder, and China National Knowledge Infrastructure (CNKI), without regard to language constraints. All eligible studies are analysed and summarised.

RESULTS

Based on the literature findings, some extracts or active metabolites divided from CMHs, including Curcumin, Resveratrol, Liquorice, Dandelions, Cortex Moutan, and Calendula officinalis L., are effective for the treatment and prevention of skin diseases because of a wide range of pharmacological activities, e.g. anti-bacterial, anti-microbial, anti-virus, and anti-inflammation to enhance the body's immune system. It is also responsible for skin whitening to prevent pigmentation and premature ageing through several mechanisms, such as regulation or inhibition of nuclear factor kappa B (IκB/NF-κB) signalling pathways.

CONCLUSION

This is possible to develop CMHs, such as Curcumin, Resveratrol, Liquorice, Dandelions, Cortex Moutan and Calendula officinalis L. The ratio of multiple CMH formulations and safety assessments on human skin diseases required studying to achieve better pharmacological activities. Nano formulations are the future investigation for CMHs to combat skin diseases.

Influence of Habitat and Effects of Salt Stress on Biochemical and Physiological Parameters of Glycyrrhiza uralensis

The seeds of Glycyrrhiza uralensis Fisch. used for cultivating are primarily sourced from wild populations. However, the types of habitats where wild G. uralensis grow are diverse. We studied the effects of salinity on the growth, antioxidant capacity, and photosynthetic physiology of two-month-old licorice seedlings from different habitats to evaluate their salt tolerance. With the increasing NaCl concentration, compared with non-salinized habitats, seedlings originating from seeds collected from salinized habitats showed milder inhibition in root biomass and root volume. Also, the crown diameter increased more significantly. Activities of superoxide dismutase, catalase, and peroxidase are higher. Correspondingly, the electrolyte leakage rate of the leaves is low. Their leaves had a higher photoprotection capacity and potential maximum photochemical efficiency of PSII. Net photosynthetic rate, transpiration rate, and stomatal conductance showed less inhibition under 4 and 6 g/kg NaCl treatment. The content of glycyrrhizic acid and glycyrrhetinic acid in their roots was significantly increased under 2 g/kg NaCl treatment and was significantly higher than that of seedlings from non-salinized habitats under the same NaCl treatment. In conclusion, seeds from salinized habitats show improved tolerance to salt stress at the seedling stage, which is attributed to their superior phenotypic adaptability, strong antioxidant, and especially high light protection ability.

18-β-glycyrrhetinic acid-loaded polymeric nanoparticles attenuate cigarette smoke-induced markers of impaired antiviral response in vitro

Tobacco smoking is a leading cause of preventable mortality, and it is the major contributor to diseases such as COPD and lung cancer. Cigarette smoke compromises the pulmonary antiviral immune response, increasing susceptibility to viral infections. There is currently no therapy that specifically addresses the problem of impaired antiviral response in cigarette smokers and COPD patients, highlighting the necessity to develop novel treatment strategies. 18-β-glycyrrhetinic acid (18-β-gly) is a phytoceutical derived from licorice with promising anti-inflammatory, antioxidant, and antiviral activities whose clinical application is hampered by poor solubility. This study explores the therapeutic potential of an advanced drug delivery system encapsulating 18-β-gly in poly lactic-co-glycolic acid (PLGA) nanoparticles in addressing the impaired antiviral immunity observed in smokers and COPD patients. Exposure of BCi-NS1.1 human bronchial epithelial cells to cigarette smoke extract (CSE) resulted in reduced expression of critical antiviral chemokines (IP-10, I-TAC, MIP-1α/1β), mimicking what happens in smokers and COPD patients. Treatment with 18-β-gly-PLGA nanoparticles partially restored the expression of these chemokines, demonstrating promising therapeutic impact. The nanoparticles increased IP-10, I-TAC, and MIP-1α/1β levels, exhibiting potential in attenuating the negative effects of cigarette smoke on the antiviral response. This study provides a novel approach to address the impaired antiviral immune response in vulnerable populations, offering a foundation for further investigations and potential therapeutic interventions. Further studies, including a comprehensive in vitro characterization and in vivo testing, are warranted to validate the therapeutic efficacy of 18-β-gly-PLGA nanoparticles in respiratory disorders associated with compromised antiviral immunity.

Glycyrrhizinic Acid as an Antiviral and Anticancer Agent in the Treatment of Human Papillomavirus

Human papillomavirus (HPV), like any other virus, needs to penetrate the host cell and make use of its machinery to replicate. From there, HPV infection can be asymptomatic or lead to benign and premalignant lesions or even different types of cancer. HPV oncogenesis is due to the ability of the viral oncoproteins E6 and E7 to alter the control mechanisms for the growth and proliferation of host cell. Therefore, the use of agents with the ability to control these processes is essential in the search for effective treatments against HPV infections. Glycyrrhizinic acid (Gly), the active ingredient in liquorice, has been shown in numerous preclinical studies to have an antiviral and anticancer activity, reducing the expression of E6 and E7 and inducing apoptosis in cervical cancer cells. In addition, it also has antioxidant, anti-inflammatory, immunomodulatory or re-epithelializing properties that can be useful in HPV infections. This review includes the different antiviral and anticancer mechanisms described for Gly, as well as the clinical studies carried out that position it as a potential therapeutic strategy against HPV both through its topical application and by oral administration.

Plant-Derived Epi-Nutraceuticals as Potential Broad-Spectrum Anti-Viral Agents

Although the COVID-19 pandemic appears to be diminishing, the emergence of SARS-CoV-2 variants represents a threat to humans due to their inherent transmissibility, immunological evasion, virulence, and invulnerability to existing therapies. The COVID-19 pandemic affected more than 500 million people and caused over 6 million deaths. Vaccines are essential, but in circumstances in which vaccination is not accessible or in individuals with compromised immune systems, drugs can provide additional protection. Targeting host signaling pathways is recommended due to their genomic stability and resistance barriers. Moreover, targeting host factors allows us to develop compounds that are effective against different viral variants as well as against newly emerging virus strains. In recent years, the globe has experienced climate change, which may contribute to the emergence and spread of infectious diseases through a variety of factors. Warmer temperatures and changing precipitation patterns can increase the geographic range of disease-carrying vectors, increasing the risk of diseases spreading to new areas. Climate change may also affect vector behavior, leading to a longer breeding season and more breeding sites for disease vectors. Climate change may also disrupt ecosystems, bringing humans closer to wildlife that transmits zoonotic diseases. All the above factors may accelerate the emergence of new viral epidemics. Plant-derived products, which have been used in traditional medicine for treating pathological conditions, offer structurally novel therapeutic compounds, including those with anti-viral activity. In addition, plant-derived bioactive substances might serve as the ideal basis for developing sustainable/efficient/cost-effective anti-viral alternatives. Interest in herbal antiviral products has increased. More than 50% of approved drugs originate from herbal sources. Plant-derived compounds offer diverse structures and bioactive molecules that are candidates for new drug development. Combining these therapies with conventional drugs could improve patient outcomes. Epigenetics modifications in the genome can affect gene expression without altering DNA sequences. Host cells can use epigenetic gene regulation as a mechanism to silence incoming viral DNA molecules, while viruses recruit cellular epitranscriptomic (covalent modifications of RNAs) modifiers to increase the translational efficiency and transcript stability of viral transcripts to enhance viral gene expression and replication. Moreover, viruses manipulate host cells' epigenetic machinery to ensure productive viral infections. Environmental factors, such as natural products, may influence epigenetic modifications. In this review, we explore the potential of plant-derived substances as epigenetic modifiers for broad-spectrum anti-viral activity, reviewing their modulation processes and anti-viral effects on DNA and RNA viruses, as well as addressing future research objectives in this rapidly emerging field.

Effectiveness of ayurvedic formulation, NAOQ19 along with standard care in the treatment of mild-moderate COVID-19 patients: A double blind, randomized, placebo-controlled, multicentric trial

BACKGROUND

Medicines in indigenous systems such as Ayurveda have strong antimicrobial activity but double-blind randomized control trials are infrequent in this system of medicine. The efficacy of a new ayurvedic formulation was evaluated during the pandemic.

METHODS

150 mild-moderate COVID-19 patients were enrolled and randomized in 1:1 to NAOQ19 and placebo group. RT-PCR was done on Day 3, 5 and 7. CBC, CRP, LFT, and KFT were assessed at baseline and exit. Duration of hospital stay was noted and clinical assessment was also performed.

RESULT

The results demonstrated more people turning RT-PCR negative in the NAOQ19 group compared to the placebo group on day 3 (p-value = 0.033). The mean time duration to turn RT-PCR negative was significantly lower in the NAOQ19 group (4.6 days) compared to placebo group (5.2 days) (p-value = 0.018). There was significant reduction in hospital stay among patients in the NAOQ19 arm who were discharged earlier (5.6 days) compared to placebo group (6.4 days) (p-value = 0.046). Patients in NAOQ19 arm did not show any adverse life-threatening events.

CONCLUSION

The ayurvedic preparation given along with standard of care therapy reduced the duration of hospital stay and there was earlier conversion to RT-PCR negative.The integrated approach can help to reduce patient workload in the hospitals as well as limit the transmission of the virus in the community.

STUDY REGISTRATION

CTRI/2021/05/033790.

Synergistic and Long-Lasting Wound Dressings Promote Multidrug-Resistant Staphylococcus Aureus-Infected Wound Healing

Background

Multidrug-resistant staphylococcus aureus infected wounds can lead to nonhealing, systemic infections, and even death. Although advanced dressings are effective in protecting, disinfecting, and maintaining moist microenvironments, they often have limitations such as single functionality, inadequate drug release, poor biosafety, or high rates of drug resistance.

Methods

Here, a novel wound dressing comprising glycyrrhizic acid (GA) and tryptophan-sorbitol carbon quantum dots (WS-CQDs) was developed, which exhibit synergistic and long-lasting antibacterial and anti-inflammatory effects. We investigated the characterization, mechanical properties, synergistic antibacterial effects, sustained-release properties, and cytotoxicity of GA/WS-CQDs hydrogels in vitro. Additionally, we performed transcriptome sequence analysis to elucidate the antibacterial mechanism. Furthermore, we evaluated the biosafety, anti-inflammatory effects, and wound healing ability of GA/WS-CQDs dressings using an in vivo mouse model of methicillin-resistant staphylococcus aureus (MRSA)-infected wounds.

Results

The prepared GA/WS-CQDs hydrogels demonstrated superior anti-MRSA effects compared to common antibiotics in vitro. Furthermore, the sustained release of WS-CQDs from GA/WS-CQDs hydrogels lasted for up to 60 h, with a cumulative release of exceeding 90%. The sustained-released WS-CQDs exhibited excellent anti-MRSA effects, with low drug resistance attributed to DNA damage and inhibition of bacterial biofilm formation. Notably, in vivo experiments showed that GA/WS-CQDs dressings reduced the expression of inflammatory factors (TNF-α, IL-1β, and IL-6) and significantly promoted the healing of MRSA-infected wounds with almost no systemic toxicity. Importantly, the dressings did not require replacement during the treatment process.

Conclusion

These findings emphasize the high suitability of GA/WS-CQDs dressings for MRSA-infected wound healing and their potential for clinical translation.

Advances in the roles of glycyrrhizic acid in cancer therapy

Since the first 70 years of reporting cancer chemotherapy, malignant tumors have been the second most common cause of death in children and adults. Currently, the commonly used anti-cancer methods include surgery, chemotherapy, radiotherapy, and immunotherapy. Although these treatment methods could alleviate cancer, they lead to different forms of side effects and have no particularly significant effect on prolonging the patients' life span. Glycyrrhizic acid (GL), a native Chinese herbal extract, has a wide range of pharmacological effects, such as anti-cancer, anti-inflammatory, antioxidant, and immune regulation. In this review, the anti-cancer effects and mechanisms of GL are summarized in various cancers. The inhibition of GL on chemotherapy-induced side effects, including hepatotoxicity, nephrotoxicity, genotoxicity, neurotoxicity and pulmonary toxicity, is highlighted. Therefore, GL may be a promising and ideal drug for cancer therapy.