Korean Red Ginseng, a regulator of NLRP3 inflammasome, in the COVID-19 pandemic

Amino Sugar-Enriched Fraction of Korean Red Ginseng Extract Induces the Priming Step of NLRP3 Inflammasome

Intracellular protein complexes, known as inflammasomes, activate caspase-1 and induce the secretion of pro-inflammatory cytokines, namely interleukin (IL)-1β and -18. Korean Red Ginseng extract (RGE) is a known immunomodulator and a potential candidate for the regulation of inflammasomes. The saponins, such as ginsenosides, of RGE inhibit inflammasome signaling, while non-saponin substances containing amino sugars promote the priming step, up-regulating inflammasome components (pro-IL-1β, NLRP3, caspase-1, and Asc). In this study, the amino sugar-enriched fraction (ASEF), which increases only non-saponin components, including amino sugars, without changing the concentration of saponin substances, was used to investigate whether saponin or non-saponin components of RGE would have a greater impact on the priming step. When murine macrophages were treated with ASEF, the gene expression of inflammatory cytokines (IL-1α, TNFα, IL-6, and IL-10) increased. Additionally, ASEF induced the priming step but did not affect the inflammasome activation step, such as the secretion of IL-1β, cleavage of caspase-1, and formation of Asc pyroptosome. Furthermore, the upregulation of gene expression of inflammasome components by ASEF was blocked by inhibitors of Toll-like receptor 4 signaling. Maltol, the main constituent of ASEF, promoted the priming step but inhibited the activation step of the inflammasome, while arginine, sugars, arginine-fructose-glucose, and fructose-arginine, the other main constituents of ASEF, had no effect on either step. Thus, certain amino sugars in RGE, excluding maltol, are believed to be the components that induce the priming step. The priming step that prepares the NLRP3 inflammasome for activation appears to be induced by amino sugars in RGE, thereby contributing to the immune-boosting effects of RGE.

Apolipoprotein C3 (ApoC3) facilitates NLRP3 mediated pyroptosis of macrophages through mitochondrial damage by accelerating of the interaction between SCIMP and SYK pathway in acute lung injury

Respiratory failure caused by severe acute lung injury (ALI) is the main cause of mortality in patients with COVID-19.This study aimed to investigate the effects and underlying biological mechanism of Apolipoprotein C3 (ApoC3) in ALI. To establish an in vivo model, C57BL/6 mice were exposed by lipopolysaccharide (LPS). For the in vitro model, murine bone marrow-derived macrophages (BMDMs) or RAW264.7 cells were stimulated with LPS + adenosine triphosphate (ATP). Serum levels of ApoC3 were found to be upregulated in patients with COVID-19 or pneumonia-induced ALI. Inhibition of ApoC3 reduced lung injury in an ALI model, while overexpression of ApoC3 promoted lung injury. ApoC3 induced mitochondrial damage-mediated pyroptosis in ALI through the activation of the NOD-like receptorprotein 3 (NLRP3) inflammasome. ApoC3 recombinant protein significantly increased SCIMP expression in the lung tissue of mice models with ALI. ApoC3 also facilitated the interaction between the SLP adapter and CSK-interacting membrane protein (SCIMP) protein and Spleen tyrosine kinase (SYK) protein in the ALI model. Moreover, ApoC3 accelerated calcium-dependent reactive oxygen species (ROS) production in the ALI model. The effects of ApoC3 on pyroptosis were mitigated by the use of a pyroptosis inhibitor or an ROS inhibitor in the ALI model. Furthermore, ApoC3 activated the expression of SYK, which in turn induced NLRP3 inflammasome-regulated pyroptosis in the ALI model. METTL3 was found to mediate the m6A mRNA expression of ApoC3. Overall, our study highlights the crucial role of ApoC3 in promoting macrophage pyroptosis in ALI through calcium-dependent ROS production and NLRP3 inflammasome activation via the SCIMP-SYK pathway, providing a potential therapeutic strategy for ALI and other inflammatory diseases.

Therapeutic potential and possible mechanisms of ginseng for depression associated with COVID-19

Recently, a global outbreak of COVID-19 has rapidly spread to various national regions. As the number of COVID-19 patients has increased, some of those infected with SARS-CoV-2 have developed a variety of psychiatric symptoms, including depression, cognitive impairment, and fatigue. A distinct storm of inflammatory factors that contribute to the initial disease but also a persistent post-acute phase syndrome has been reported in patients with COVID-19. Neuropsychological symptoms including depression, cognitive impairment, and fatigue are closely related to circulating and local (brain) inflammatory factors. Natural products are currently being examined for their ability to treat numerous complications caused by COVID-19. Among them, ginseng has anti-inflammatory, immune system stimulating, neuroendocrine modulating, and other effects, which may help improve psychiatric symptoms. This review summarizes the basic mechanisms of COVID-19 pneumonia, psychiatric symptoms following coronavirus infections, effects of ginseng on depression, restlessness, and other psychiatric symptoms associated with post-COVID syn-dromes, as well as possible mechanisms underlying these effects.

In silico and in vitro inhibition of host-based viral entry targets and cytokine storm in COVID-19 by ginsenoside compound K

SARS-CoV-2 is a novel coronavirus that emerged as an epidemic, causing a respiratory disease with multiple severe symptoms and deadly consequences. ACE-2 and TMPRSS2 play crucial and synergistic roles in the membrane fusion and viral entry of SARS-CoV-2 (COVID-19). The spike (S) protein of SARS-CoV-2 binds to the ACE-2 receptor for viral entry, while TMPRSS2 proteolytically cleaves the S protein into S1 and S2 subunits, promoting membrane fusion. Therefore, ACE-2 and TMPRSS2 are potential drug targets for treating COVID-19, and their inhibition is a promising strategy for treatment and prevention. This study proposes that ginsenoside compound K (G-CK), a triterpenoid saponin abundant in Panax Ginseng, a dietary and medicinal herb highly consumed in Korea and China, effectively binds to and inhibits ACE-2 and TMPRSS2 expression. We initially conducted an in-silico evaluation where G-CK showed a high affinity for the binding sites of the two target proteins of SARS-CoV-2. Additionally, we evaluated the stability of G-CK using molecular dynamics (MD) simulations for 100 ns, followed by MM-PBSA calculations. The MD simulations and free energy calculations revealed that G-CK has stable and favorable energies, leading to strong binding with the targets. Furthermore, G-CK suppressed ACE2 and TMPRSS2 mRNA expression in A549, Caco-2, and MCF7 cells at a concentration of 12.5 μg/mL and in LPS-induced RAW 264.7 cells at a concentration of 6.5 μg/mL, without significant cytotoxicity.ACE2 and TMPRSS2 expression were significantly lower in A549 and RAW 264.7 cells following G-CK treatment. These findings suggest that G-CK may evolve as a promising therapeutic against COVID-19.

The effects and mechanisms of the anti-COVID-19 traditional Chinese medicine, Dehydroandrographolide from Andrographis paniculata (Burm.f.) Wall, on acute lung injury by the inhibition of NLRP3-mediated pyroptosis

BACKGROUND

Dehydroandrographolide (Deh) from Andrographis paniculata (Burm.f.) Wall has strong anti-inflammatory and antioxidant activities.

PURPOSE

To explore the role of Deh in acute lung injury (ALI) of coronavirus disease 19 (COVID-19) and its inflammatory molecular mechanism.

METHODS

Liposaccharide (LPS) was injected into a C57BL/6 mouse model of ALI, and LPS + adenosine triphosphate (ATP) was used to stimulate BMDMs in an in vitro model of ALI.

RESULTS

In an in vivo and in vitro model of ALI, Deh considerably reduced inflammation and oxidative stress by inhibiting NLRP3-mediated pyroptosis and attenuated mitochondrial damage to suppress NLRP3-mediated pyroptosis through the suppression of ROS production by inhibiting the Akt/Nrf2 pathway. Deh inhibited the interaction between Akt at T308 and PDPK1 at S549 to promote Akt protein phosphorylation. Deh directly targeted PDPK1 protein and accelerated PDPK1 ubiquitination. 91-GLY, 111-LYS, 126-TYR, 162-ALA, 205-ASP and 223-ASP may be the reason for the interaction between PDPK1 and Deh.

CONCLUSION

Deh from Andrographis paniculata (Burm.f.) Wall presented NLRP3-mediated pyroptosis in a model of ALI through ROS-induced mitochondrial damage through inhibition of the Akt/Nrf2 pathway by PDPK1 ubiquitination. Therefore, it can be concluded that Deh may be a potential therapeutic drug for the treatment of ALI in COVID-19 or other respiratory diseases.

Protective effects of Korean Red Ginseng against toxicity of endocrine-disrupting chemicals

Several chemicals have been developed owing to the progression of industrialization, among which endocrine-disrupting chemicals (EDCs; essential for plastic production) are used as plasticizers and flame retardants. Plastics have become an essential element in modern life because they provide convenience, thus increasing EDCs exposure to humans. EDCs cause adverse effects such as deterioration of reproductive function, cancer, and neurological abnormalities by disrupting the endocrine system and hence are classified as "dangerous substances." Additionally, they are toxic to various organs but continue to be used. Therefore, it is necessary to review the contamination status of EDCs, select potentially hazardous substances for management, and monitor the safety standards. In addition, it is necessary to discover substances that can protect against EDC toxicity and conduct active research on the protective effects of these substances. According to recent research, Korean Red Ginseng (KRG) exhibits protective effects against several toxicities caused by EDCs to humans. In this review, the effects of EDCs on the human body and the role of KRG in protection against EDC toxicity are discussed.

Recent Advances in Yeast Recombinant Biosynthesis of the Triterpenoid Protopanaxadiol and Glycosylated Derivatives Thereof

Plant natural products are a seemingly endless resource for novel chemical structures. However, their extraction often results in high prices, fluctuation in both quantity and quality, and negative environmental impact. The latter might result from the extraction procedure but more often from the high amount of plant biomass required. With the advent of synthetic biology, producing natural plant products in large quantities using yeasts as hosts has become possible. Here, we focus on the recent advances in metabolic engineering of the yeasts species Saccharomyces cerevisiae and Yarrowia lipolytica for the synthesis of ginsenoside triterpenoids, namely, dammarenediol-II, protopanaxadiol, protopanaxatriol, compound K, ginsenoside Rh1, ginsenoside Rh2, ginsenoside Rg3, and ginsenoside F1. A discussion is provided on advanced synthetic biology, bioprocess strategies, and current challenges for the biosynthesis of ginsenoside triterpenoids. Finally, future directions in metabolic and process engineering are summarized and may help reify sustainable ginsenoside production.

Production and characterization of lentivirus vector-based SARS-CoV-2 pseudoviruses with dual reporters: Evaluation of anti-SARS-CoV-2 viral effect of Korean Red Ginseng

Background

Pseudotyped virus systems that incorporate viral proteins have been widely employed for the rapid determination of the effectiveness and neutralizing activity of drug and vaccine candidates in biosafety level 2 facilities. We report an efficient method for producing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus with dual luciferase and fluorescent protein reporters. Moreover, using the established method, we also aimed to investigate whether Korean Red Ginseng (KRG), a valuable Korean herbal medicine, can attenuate infectivity of the pseudotyped virus.

Methods

A pseudovirus of SARS-CoV-2 (SARS-2pv) was constructed and efficiently produced using lentivirus vector systems available in the public domain by the introduction of critical mutations in the cytoplasmic tail of the spike protein. KRG extract was dose-dependently treated to Calu-3 cells during SARS2-pv treatment to evaluate the protective activity against SARS-CoV-2.

Results

The use of Calu-3 cells or the expression of angiotensin-converting enzyme 2 (ACE2) in HEK293T cells enabled SARS-2pv infection of host cells. Coexpression of transmembrane protease serine subtype 2 (TMPRSS2), which is the activator of spike protein, with ACE2 dramatically elevated luciferase activity, confirming the importance of the TMPRSS2-mediated pathway during SARS-CoV-2 entry. Our pseudovirus assay also revealed that KRG elicited resistance to SARS-CoV-2 infection in lung cells, suggesting its beneficial health effect.

Conclusion

The method demonstrated the production of SARS-2pv for the analysis of vaccine or drug candidates. When KRG was assessed by the method, it protected host cells from coronavirus infection. Further studies will be followed for demonstrating this potential benefit.

Panax ginseng as a potential therapeutic for neurological disorders associated with COVID-19; Toward targeting inflammasome

Coronavirus disease 2019 (COVID-19) is a highly infectious respiratory disease caused by a severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). SARS-CoV-2 infection may cause clinical manifestations of multiple organ damage, including various neurological syndromes. There are currently two oral antiviral drugs-Paxlovid and molnupiravir-that are recognized to treat COVID-19, but there are still no drugs that can specifically fight the challenges of SARS-CoV-2 variants. Nucleotide-binding oligomerization domain-like receptor pyrin domain-containing-3 (NLRP3) inflammasome is a multimolecular complex that can sense heterogeneous pathogen-associated molecular patterns associated with neurological disorders. The NLRP3 activation stimulates the production of caspase-1-mediated interleukin (IL)-1β, IL-18, and other cytokines in immune cells. Panax (P.) ginseng is a medicinal plant that has traditionally been widely used to boost immunity and treat various pathological conditions in the nervous system due to its safety and anti-inflammatory/oxidant/viral activities. Several recent reports have indicated that P. ginseng and its active ingredients may regulate NLRP3 inflammasome activation in the nervous system. Therefore, this review article discusses the current knowledge regarding the pathogenesis of neurological disorders related to COVID-19 and NLRP3 inflammasome activation and the possibility of using P. ginseng in a strategy targeting this pathway to treat neurological disorders.

JC2-11, a benzylideneacetophenone derivative, attenuates inflammasome activation

Dysregulation of inflammasome activation induces chronic and excess inflammation resulting in several disorders, such as metabolic disorders and cancers. Thus, screening for its regulator derived from natural materials has been conducted progressively. JC2-11 (JC) was designed to enhance the antioxidant activity based on a chalcone, which is abundant in edible plants and a precursor of flavonoids. This study examined the effects of JC on inflammasome activation in human and murine macrophages. JC inhibited the secretion of interleukin (IL)-1β and lactate dehydrogenases, and the cleavage of caspase-1 and gasdermin D in response to the tested activators (i.e., NLRP3, NLRC4, AIM2, and non-canonical inflammasome triggers). In addition, JC attenuated IL-1β secretion from lipopolysaccharide (LPS)-injected mice, an inflammasome-mediating disease model. Mechanistically, JC blocked the expression of the inflammasome components during the priming step of the inflammasome, and interrupted the production of mitochondrial reactive oxygen species. In addition, JC inhibited the activity of caspase-1. In conclusion, JC may be a candidate pan-inflammasome inhibitor.

Ginseng as a Key Immune Response Modulator in Chinese Medicine: From Antipandemic History to COVID-19 Management

The cytokine storm plays an indispensable role in the severe and critical illness and death of the COVID-19 vulnerable population. Thus, suppressing the cytokine storm is of great significance. Ginseng is a traditional Chinese herb originally used for improving physiological conditions and ameliorating disease. Common throughout the history of ancient Chinese medicine is utilizing ginseng as a major ingredient to successfully fight various pandemics, and the most famous decoction is Renshen Baidu powder. In recent years, ginseng has been observed to provide preventive and therapeutic benefits in the treatment of various conditions by suppressing hyper-inflammation, inhibiting virus intrusion, and balancing the host's immunity. This paper summarizes the ancient Chinese medicine books' recordings of, the clinical practice of, and the laboratory exploration of ginseng for the treatment of pandemics and COVID-19. Ginseng and its active ingredients were found to downregulate inflammatory cytokines, upregulate anti-inflammatory cytokines, stimulate the secretion of the antiviral cytokine IFN-[Formula: see text], prevent viral entry and replication, and improve viral clearance. Furthermore, ginseng modulates both natural and acquired immunity during viral infection. Collectively, we propose that ginseng can act as a key immune response modulator against the cytokine storm of COVID-19. This paper may provide a new approach to discover specific medications using ginseng to combat COVID-19.

Maltol, a Natural Flavor Enhancer, Inhibits NLRP3 and Non-Canonical Inflammasome Activation

Maltol (3-hydroxy-2-methyl-4-pyrone) is used widely as a food and cosmetic supplement, and it has antioxidant and anti-inflammatory activities. Inflammasome causes the maturation and secretion of interleukin (IL)-1β and -18 through the activation of caspase-1 (Casp1), which contributes to various inflammatory diseases. This study examined the effects of maltol on the inflammasome activation in macrophages and mice. Lipopolysaccharide (LPS)-primed macrophages were treated with a trigger of NLRP3, NLRC4, AIM2, or non-canonical (NC) inflammasomes in the presence of maltol. The secretion of IL-1β and IL-18 and the cleavage of Casp1 were analyzed as indices of inflammasome activation. Mice were injected with LPS and an NLRP3 trigger with or without maltol, and the peritoneal IL-1β secretions were observed. The effects of maltol on reactive oxygen species (ROS) production and Casp1 activity were analyzed to determine the mechanism. Maltol inhibited the activation of NLRP3 and NC inflammasomes, but it did not alter the other inflammasomes. Maltol also attenuated IL-1β secretion resulting from the inflammasome activation in mice. The anti-inflammatory mechanism of maltol was revealed by the inhibition of ROS production and Casp1 activity. Maltol is suggested to be promising as a anti-inflammasome molecule.