In vivo and in vitro anti-inflammatory activities of Persicaria chinensis methanolic extract targeting Src/Syk/NF-κB

Unveiling the potential mechanisms of Amomi fructus against gastric ulcers via integrating network pharmacology and in vivo experiments

ETHNOPHARMACOLOGICAL RELEVANCE

As a well-known traditional Chinese medicine, Amomi fructus (A. fructus) (Sharen) has been used therapeutically to treat gastrointestinal illnesses, including gastric ulcer (GU). The mechanism underlying this impact is still not fully known, though.

AIM OF THE STUDY

To investigate the hidden mechanism by which A. fructus influences the pathogenesis of GU, we employed network pharmacology approaches and in vivo validated studies.

MATERIALS AND METHODS

Multiple public databases were used to compile information on bioactive compounds, potential targets of A. fructus, and associated genes of GU. Then, the STRING database's protein-protein interaction (PPI) data of the drug-disease overlapping gene targets was obtained, and the core targets for A. fructus against GU were discovered. Additionally, molecular docking was done to examine the binding capabilities of the active substances and core targets. Then, the pathways of A. fructus that target GU were examined using the Annotation, Visualization and Integrated Discovery (DAVID)'s Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway studies. In a mouse model of acute stomach mucosal damage brought on by absolute ethanol, the findings of network pharmacology were finally validated.

RESULTS

In total, 610 targets derived from the 196 bioactive compounds in A. fructus, were discovered, and along with 115 A. fructus target genes for therapy of GU. Then, ten core targets associated with apoptosis and inflammation were determined based on node degree, and ALB, AKT1, TNF, EGFR, MAPK3, CASP3, MMP9, STAT3, SRC, and HRAS were identified as promising therapeutic targets of A. fructus against GU. The results of molecular docking also revealed that 65 active compounds had strong binding activity with the core targets, with volatile chemicals being the most significant active ingredients. So, for following in vivo tests, A. fructus volatile oils (AVO) were used. The KEGG analysis showed that the phosphoinositide-3-kinase/protein kinase B (PI3K/AKT) signaling pathway may be crucial for the therapeutic mechanism of GU. In experiments that were validated in vivo, AVO considerably decreased the ulcer area and enhanced the histological appearance of the gastric tissues. In addition, compared to the model group, up-regulated the expression of IGF-1, p-PI3K, and p-AKT and down-regulated the protein levels of TNF-α and Caspase 3 in the stomach tissues.

CONCLUSION

According to preliminary findings from this work, A. fructus may influence inflammatory response and apoptosis via regulating the PI3K/AKT signaling pathway and associated gene targets. Importantly, our research might offer a theoretical foundation for future research into the intricate anti-GU mechanism of A. fructus.

Study on the Alleviating Effect and Potential Mechanism of Ethanolic Extract of Limonium aureum (L.) Hill. on Lipopolysaccharide-Induced Inflammatory Responses in Macrophages

Inflammation is the host response of immune cells during infection and traumatic tissue injury. An uncontrolled inflammatory response leads to inflammatory cascade, which in turn triggers a variety of diseases threatening human and animal health. The use of existing inflammatory therapeutic drugs is constrained by their high cost and susceptibility to systemic side effects, and therefore new therapeutic candidates for inflammatory diseases need to be urgently developed. Natural products are characterized by wide sources and rich pharmacological activities, which are valuable resources for the development of new drugs. This study aimed to uncover the alleviating effect and potential mechanism of natural product Limonium aureum (LAH) on LPS-induced inflammatory responses in macrophages. The experimental results showed that the optimized conditions for LAH ultrasound-assisted extraction via response surface methodology were an ethanol concentration of 72%, a material-to-solvent ratio of 1:37 g/mL, an extraction temperature of 73 °C, and an extraction power of 70 W, and the average extraction rate of LAH total flavonoids was 0.3776%. Then, data of 1666 components in LAH ethanol extracts were obtained through quasi-targeted metabolomics analysis. The ELISA showed that LAH significantly inhibited the production of pro-inflammatory cytokines while promoting the secretion of anti-inflammatory cytokines. Finally, combined with the results of network pharmacology analysis and protein expression validation of hub genes, it was speculated that LAH may alleviate LPS-induced inflammatory responses of macrophages through the AKT1/RELA/PTGS2 signaling pathway and the MAPK3/JUN signaling pathway. This study preliminarily revealed the anti-inflammatory activity of LAH and the molecular mechanism of its anti-inflammatory action, and provided a theoretical basis for the development of LAH as a new natural anti-inflammatory drug.

The Antioxidant and Immunomodulatory Potential of Coccoloba alnifolia Leaf Extracts

Oxidative stress has been associated with different diseases, and different medicinal plants have been used to treat or prevent this condition. The leaf ethanolic extract (EE) and aqueous extract (AE) from Coccoloba alnifolia have previously been characterized to have antioxidant potential in vitro and in vivo. In this study, we worked with EE and AE and two partition phases, AF (ethyl acetate) and BF (butanol), from AE extract. These extracts and partition phases did not display cytotoxicity. The EE and AE reduced NO production and ROS in all three concentrations tested. Furthermore, it was observed that EE and AE at 500 μg/mL concentration were able to reduce phagocytic activity by 30 and 50%, respectively. A scratch assay using a fibroblast cell line (NHI/3T3) showed that extracts and fractions induced cell migration with 60% wound recovery within 24 h, especially for BF. It was also observed that AF and BF had antioxidant potential in all the assays evaluated. In addition, copper chelation was observed. This activity was previously not detected in AE. The HPLC-DAD analysis showed the presence of phenolic compounds such as p-cumaric acid and vitexin for extracts, while the GNPS annotated the presence of isoorientin, vitexin, kanakugiol, and tryptamine in the BF partition phase. The data presented here demonstrated that the EE, AE, AF, and BF of C. alnifolia have potential immunomodulatory effects, antioxidant effects, as well as in vitro wound healing characteristics, which are important for dynamic inflammation process control.

Isolation and Identification of Plant-Growth Inhibitory Constituents from Polygonum chinense Linn and Evaluation of Their Bioherbicidal Potential

Polygonum chinense Linn. is a medicinal and invasive plant that belongs to the family Polygonaceae. The pharmacological activities and phytochemical constituents of Polygonum chinense are well reported, but the allelopathic effects and potent allelopathic substances of P. chinense remain to be investigated. Hence, this experiment was conducted to separate and characterize potentially allelopathic substances from an extract of the Polygonum chinense plant. The Polygonum chinense plant extracts highly suppressed the growth of cress (Lepidium sativum L.), lettuce (Lactuca sativa L.), barnyard grass (Echinochloa crusgalli (L.) P. Beauv.), and timothy grass (Phleum pratense L.) seedlings in a species- and concentration-dependent way. Two active substances were separated using a series of purification procedures and determined through spectral analysis as (-)-3-hydroxy-β-ionone and (-)-3-hydroxy-7,8-dihydro-β-ionone. These two compounds significantly suppressed the seedling growth of Lepidium sativum (cress) at concentrations of 0.01 and 1 mM, respectively. The extract concentrations necessary for 50% growth inhibition (I₅₀ values) of the cress hypocotyls and roots were 0.05 and 0.07 mM for (-)-3-hydroxy-β-ionone, respectively, and 0.42 and 1.29 mM for (-)-3-hydroxy-7,8-β-ionone, respectively. These findings suggest that these two compounds are in charge of the inhibitory effects of the Polygonum chinense extract and may serve as weed control agents.

Crosstalk between phytochemicals and inflammatory signaling pathways

Novel bioactive constituents from natural sources are actively being investigated. The phytochemicals in these phenolic compounds are believed to have a variety of beneficial effects on human health. Several phenolic compounds have been found in plants. The antioxidant potential of phenols has been discussed in numerous studies along with their anti-inflammatory effects on pro-inflammatory cytokine, inducible cyclooxygenase-2, and nitric oxide synthase. Through current study, an attempt is made to outline and highlight a wide variety of inflammation-associated signaling pathways that have been modified by several natural compounds. These signaling pathways include nuclear factor-kappa B (NF-кB), activator protein (AP)-1, protein tyrosine kinases (PTKs), mitogen-activated protein kinases (MAPKs), nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factors, tyrosine phosphatidylinositol 3-kinase (PI3K)/AKT, and the ubiquitin-proteasome system. In light of the influence of natural substances on signaling pathways, their impact on the production of inflammatory mediator is highlighted in this review.

Network Pharmacological Study on the Mechanism of Cynanchum paniculatum (Xuchangqing) in the Treatment of Bungarus multicinctus Bites

Background

Bungarus multicinctus is one of the top ten venomous snakes in China. Its venom is mainly neurotoxin-based. Novel antivenom drugs need to be further researched and developed.

Objective

This study aimed to explore the molecular mechanism of Cynanchum paniculatum in treating Bungarus multicinctus bites based on network pharmacology. Material and methods. The potential active ingredients of Cynanchum paniculatum were screened and their SDF structures were obtained using the PubChem database and imported into the SwissTargetPrediction database, and targets were obtained for the antitoxin effects of Cynanchum paniculatum in the treatment of Bungarus multicinctus bites. The Cynanchum paniculatum-active compound-potential target network and protein-protein interaction network were constructed by using Cytoscape software, and then biological function analysis and KEGG pathway enrichment analysis were performed using the DAVID.

Results

Seven potential active components (cynapanoside C, cynatratoside B, tomentolide A, sitosterol, sarcostin, tomentogenin, and paeonol) and 286 drug targets were obtained, including 30 key targets for the treatment of bungarotoxin toxicity. The active components mainly acted on PIK3CA, MAPK1, MAP2K1, JAK2, FYN, ACHE, CHRNA7, CHRNA4, and CHRNB2, and they antagonized the inhibitory effect of bungarotoxin on the nervous system through cholinergic synapses and the neurotrophin signaling pathway.

Conclusions

Cynanchum paniculatum exerts a therapeutic effect on Bungarus multicinctus bites through multiple active components, multiple targets, and multiple pathways. The findings provide a theoretical basis for the extraction of active components of Cynanchum paniculatum and for related antivenom experiments.

An Update on Phytochemicals and Pharmacological Activities of the Genus Persicaria and Polygonum

The discovery of new pharmaceutical identities, particularly anti-infective agents, represents an urgent need due to the increase in immunocompromised patients and the ineffectiveness/toxicity of the drugs currently used. The scientific community has recognized in the last decades the importance of the plant kingdom as a huge source of novel molecules which could act against different type of infections or illness. However, the great diversity of plant species makes it difficult to select them with probabilities of success, adding to the fact that existing information is difficult to find, it is atomized or disordered. Persicaria and Polygonum constitute two of the main representatives of the Polygonaceae family, which have been extensively used in traditional medicine worldwide. Important and structurally diverse bioactive compounds have been isolated from these genera of wild plants; among them, sesquiterpenes and flavonoids should be remarked. In this article, we firstly mention all the species reported with pharmacological use and their geographical distribution. Moreover, a number of tables which summarize an update detailing the type of natural product (extract or isolated compound), applied doses, displayed bioassays and the results obtained for the main bioactivities of these genera cited in the literature during the past 40 years. Antimicrobial, antioxidant, analgesic and anti-inflammatory, antinociceptive, anticancer, antiviral, antiparasitic, anti-diabetic, antipyretic, hepatoprotective, diuretic, gastroprotective and neuropharmacological activities were explored and reviewed in this work, concluding that both genera could be the source for upcoming molecules to treat different human diseases.

Inonotsuoxide B regulates M1 to M2 macrophage polarization through sirtuin-1/endoplasmic reticulum stress axis

We explored the effect of tetracyclic triterpenoid inonotsuoxide B (IB) extracts of Inonotus obliquus on M1 to M2 macrophage polarization and its possible underlying mechanism. Lipopolysaccharide (LPS)-activated M1 macrophages exert pro-inflammatory effects and release inflammatory cytokines including interleukin (IL)-1β and tumor necrosis factor (TNF)-α. The model and various groups were treated with different IB concentrations (2.5, 5, and 10 μg/mL) to observe changes in the M1 and M2 phenotypes, gene expression of NAD-dependent deacetylase sirtuin-1 (Sirt1), and endoplasmic reticulum stress (ERS). SIRT1-siRNA and thapsigargin (TG), an ERS agonist, were used to examine the relationship between SIRT1/ERS and the effect of IB on M1 to M2 RAW264.7 macrophage phenotypic changes. We found that IB had no effect on RAW264.7 cell proliferation at 10 μg/mL. Increasing concentrations of IB (2.5, 5, and 10 μg/mL) decreased the number of phenotypic M1 macrophages and, consequently, decreased the release of the inflammatory cytokines, IL-1β and TNF-α. Furthermore, IB treatment increased the level of phenotypic M2 macrophages, which increased the release of anti-inflammatory cytokines such as arginase (Arg)-1 and found in inflammatory zone 1 (FIZZ1) in a dose-dependent manner. Further, we found that IB increased the expression of SIRT1 and inhibited that of ERS. Inhibition of Sirt1 expression by siRNA significantly increased that of ERS marker genes and IL1β. Excessive ERS levels inhibited the IB-induced transformation of phenotypic M1 macrophage to the M2 macrophage phenotype. Therefore, IB, an extract of I. obliquus, may regulate macrophage polarization through the SIRT1/ERS signaling pathway.

Mechanism of rutaecarpine on ethanol-induced acute gastric ulcer using integrated metabolomics and network pharmacology

This study was aimed to explore the mechanism of rutaecarpine (RUT) on ethanol-induced gastric ulcer (GU) in mice by integrated approaches. At first, the efficacy was determined through the macroscopic and microscopic state of stomach tissue and the expression levels of GU-related factors. Then, the serum metabolomics method based on UPLC-Q-TOF/MS was used to explore the specific metabolites and metabolic pathways. Finally, the upstream key protein targets of these specific metabolites were analyzed by network pharmacology and verified by PCR to explore the potential mechanism. RUT alleviated the histological and pathological damage of gastric tissue caused by ethanol, and could remarkably ameliorate the level of GU-related factors. Subsequently, a total of 7 potential metabolites involved in 9 metabolic pathways were identified by metabolomics analysis. Then, a 'component-targets-metabolites' interaction network was constructed, and therefore 4 key target proteins (PLA2G1B, PDE5A, MIF and SRC) that may regulate the specific metabolites were obtained. This case was further verified by the results of PCR. ALL the above results strongly demonstrated that RUT exerted a gastroprotective effect against GU. And it is the first time to combine metabolomics combined with network pharmacology to elucidate the mechanism of RUT on GU, which may be related to the regulation of energy metabolism, oxidative stress, and inflammation, and these pathways may be regulated through the upstream protein PLA2G1B, PDE5A, MIF and SRC.

Anti-Inflammatory Activity of Extracts and Pure Compounds Derived from Plants via Modulation of Signaling Pathways, Especially PI3K/AKT in Macrophages

The plant kingdom is a source of important therapeutic agents. Therefore, in this review, we focus on natural compounds that exhibit efficient anti-inflammatory activity via modulation signaling transduction pathways in macrophage cells. Both extracts and pure chemicals from different species and parts of plants such as leaves, roots, flowers, barks, rhizomes, and seeds rich in secondary metabolites from various groups such as terpenes or polyphenols were included. Selected extracts and phytochemicals control macrophages biology via modulation signaling molecules including NF-κB, MAPKs, AP-1, STAT1, STAT6, IRF-4, IRF-5, PPARγ, KLF4 and especially PI3K/AKT. Macrophages are important immune effector cells that take part in antigen presentation, phagocytosis, and immunomodulation. The M1 and M2 phenotypes are related to the production of pro- and anti-inflammatory agents, respectively. The successful resolution of inflammation mediated by M2, or failed resolution mediated by M1, may lead to tissue repair or chronic inflammation. Chronic inflammation is strictly related to several disorders. Thus, compounds of plant origin targeting inflammatory response may constitute promising therapeutic strategies.

BAY61-3606 protects kidney from acute ischemia/reperfusion injury through inhibiting spleen tyrosine kinase and suppressing inflammatory macrophage response

Acute kidney injury (AKI) is a highly prevalent clinical syndrome with high mortality and morbidity. Previous studies indicated that inflammation promotes tubular damage and plays a key role in AKI progress. Spleen tyrosine kinase (Syk) has been linked to macrophage-related inflammation in AKI. Up to date, however, no Syk-targeted therapy for AKI has been reported. In this study, we employed both cell model of LPS-induced bone marrow-derived macrophage (BMDM) and mouse model of ischemia/reperfusion injury (IRI)-induced AKI to evaluate the effects of a Syk inhibitor, BAY61-3606 (BAY), on macrophage inflammation in vitro and protection of kidney from AKI in vivo. The expression and secretion of inflammatory cytokines, both in vitro and in vivo, were significantly inhibited even back to normal levels by BAY. The upregulated serum creatinine and blood urea nitrogen levels in the AKI mice were significantly reduced after administration of BAY, implicating a protective effect of BAY on kidneys against IRI. Further analyses from Western blot, immunofluorescence staining and flow cytometry revealed that BAY inhibited the Mincle/Syk/NF-κB signaling circuit and reduced the inflammatory response. BAY also inhibited the reactive oxygen species (ROS), which further decreased the formation of inflammasome and suppressed the mature of IL-1β and IL-18. Notably, these inhibitory effects of BAY on inflammation and inflammasome in BMDM were significantly reversed by Mincle ligand, trehalose-6,6-dibehenate. In summary, these findings provided compelling evidence that BAY may be an efficient inhibitor of the Mincle/Syk/NF-κB signaling circuit and ROS-induced inflammasome, which may help to develop Syk-inhibitors as novel therapeutic agents for AKI.

Sorbaria kirilowii Ethanol Extract Exerts Anti-Inflammatory Effects In Vitro and In Vivo by Targeting Src/Nuclear Factor (NF)-κB

Inflammation is a fundamental process for defending against foreign antigens that involves various transcriptional regulatory processes as well as molecular signaling pathways. Despite its protective roles in the human body, the activation of inflammation may also convey various diseases including autoimmune disease and cancer. Sorbaria kirilowii is a plant originating from Asia, with no anti-inflammatory activity reported. In this paper, we discovered an anti-inflammatory effect of S. kirilowii ethanol extract (Sk-EE) both in vivo and in vitro. In vitro effects of Sk-EE were determined with lipopolysaccharide (LPS)-stimulated RAW264.7 cells, while ex vivo analysis was performed using peritoneal macrophages of thioglycollate (TG)-induced mice. Sk-EE significantly reduced the nitric oxide (NO) production of induced macrophages and inhibited the expression of inflammation-related cytokines and the activation of transcription factors. Moreover, treatment with Sk-EE also decreased the activation of proteins involved in nuclear factor (NF)-κB signaling cascade; among them, Src was a prime target of Sk-EE. For in vivo assessment of the anti-inflammatory effect of Sk-EE, HCl/EtOH was given by the oral route to mice for gastritis induction. Sk-EE injection dose-dependently reduced the inflammatory lesion area of the stomach in gastritis-induced mice. Taking these results together, Sk-EE exerts its anti-inflammatory activity by regulating intracellular NF-κB signaling pathways and also shows an authentic effect on reducing gastric inflammation.

Photoaging Protective Effects of Ranunculus bulumei Methanol Extract

Ultraviolet B (UVB) radiation is the main cause of photoaging processes including cellular senescence, skin drying, collagen degradation, melanogenesis, and inflammation. These responses occur because UVB induces a change in expression of aging-related genes through regulation of signal pathways such as that of mitogen-activated protein kinases- (MAPKs-) activator protein 1 (AP-1). Ranunculus bulumei, which is used as an herb in Indonesia, belongs to the Ranunculaceae family, which has been reported to perform various physiological effects including antioxidant and anti-inflammation. However, data on the pharmaceutical and cosmeceutical utility of Ranunculus bulumei have not been reported. Therefore, we evaluated the antiaging efficacy of RB-ME, a methanol extract of Ranunculus bulumei. Rb-ME attenuated MMP9 and COX-2 gene expression but enhanced SIRT1 and type-1 collagen in UVB-irradiated HaCaT cells. Rb-ME regulated these gene expressions through inhibition of p38 phosphorylation and inactivation of AP-1. In addition, mRNA expression of HAS-2 and -3, which are involved in skin hydration, was elevated in Rb-ME-treated HaCaT cells. Rb-ME also inhibited melanogenesis by suppression of tyrosinase, MITF, and TYRP-1 mRNA in B16F10 cells under α-MSH treatment. Taken together, these results indicate that Rb-ME has a protective effect on some UVB-induced skin photoaging events such as inflammation, collagen degradation, cellular senescence, skin drying, and melanin production through inhibition of the p38-AP-1 signal cascade, indicating that Rb-ME can be used as an active ingredient for antiaging cosmetics.

Phytochemical and anti-inflammatory properties of Scurrula ferruginea (Jack) Danser parasitising on three different host plants elucidated by NMR-based metabolomics

INTRODUCTION

Scurrula ferruginea (Jack) Danser is a hemi-parasitic shrub that is widely used as a traditional herbal medicine.

OBJECTIVES

To elucidate the anti-inflammatory activity of S. ferruginea parasitising on three different hosts of Vitex negundo L., Micromelum minutum (G. Forst.) Wight & Arn. and Tecoma stans (L.) Juss ex HBK., as well as, to determine the metabolite differences related to their anti-inflammatory properties.

MATERIALS AND METHODS

Two plant parts of S. ferruginea, stems and leaves, were extracted in water. The freeze-dried stem of S. ferruginea grown on T. stans was liquid-liquid partitioned into several solvents. Their potential anti-inflammatory activity was assessed via inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS) and interferon-γ (IFN-γ)-induced RAW 264.7 macrophage cells. The metabolite variation was examined using proton nuclear magnetic resonance (¹ H-NMR) combined with multivariate data analysis (MVDA).

RESULTS

Scurrula ferruginea stems parasitising on T. stans and V. negundo which were freeze dried exhibited higher anti-inflammatory activity with IC₅₀ values of 114.47 ± 2.96 and 118.87 ± 2.31 μg/mL, respectively. The mid-polar ethyl acetate fraction of S. ferruginea hosted on T. stans displayed the highest NO inhibition with 84.80 ± 0.45% at 200 μg/mL. Principal component analysis (PCA) indicated notable and clear discriminations among the different plant parts and host plants based on the identified metabolites. Furthermore, partial least squares (PLS) regression model suggested the anti-inflammatory bioactivity might be associated with the presence of choline, isoleucine, catechin, leucine and chlorogenic acid.

CONCLUSION

This study suggests S. ferruginea could serve as a potential anti-inflammatory agent, highlighting the importance of T. stans as the host plant.

Mangiferin improves hepatic damage-associated molecular patterns, lipid metabolic disorder and mitochondrial dysfunction in alcohol hepatitis rats

This study was conducted to investigate the beneficial effects and possible mechanism of action of mangiferin (MF) in alcohol hepatitis (AH) rats. Building on our previous study, the damage-associated molecular patterns (DAMPs), lipid metabolic disorder and mitochondrial dysfunction were investigated. MF effectively regulated the abnormal liver function, the levels of alcohol, FFAs and metal elements in serum. More importantly, MF improved the expression levels of mRNA and protein of PPAR-γ, OPA-1, Cav-1, EB1, NF-κB p65, NLRP3, Cas-1 and IL-1β, and decreased the positive protein expression rates of HSP90, HMGB1, SYK, CCL20, C-CAS-3, C-PARP and STARD1. Additionally, MF decreased the levels of fumarate, cAMP, xanthurenic acid and d-glucurone-6,3-lactone, and increased the levels of hippuric acid and phenylacetylglycine, and then adjusted the changes of phenylalanine metabolism, TCA cycle and ascorbate and aldarate metabolic pathways. The above results suggested that MF can effectively prevent AH by modulating specific AH-associated genes, potential biomarkers and metabolic pathways in AH rats, etc.

An ethanol extract of the rhizome of Atractylodes chinensis exerts anti-gastritis activities and inhibits Akt/NF-κB signaling

ETHNOPHARMACOLOGICAL RELEVANCE

The rhizome of Atractylodes chinensis (DC.) kodiz (Compositae) has traditionally been used to treat inflammatory disorders such as arthritis and stomach ache, but scanted report has been issued on its anti-inflammatory mechanisms.

AIM OF THE STUDY

Here, we investigated the anti-gastritis activities and explored the mechanism of action of an ethanolic extract of the herb (Ac-EE).

MATERIALS AND METHODS

Ac-EE was prepared with 95% ethanol. To determine its in vivo effects, we employed an HCl/EtOH-induced gastritis rat model. We used a lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage model for in vitro assays. Griess and MTT assays were used to measure nitric oxide (NO) production and cell viability, respectively. We used real-time PCR to determine mRNA levels. To measure prostaglandin E₂ (PGE₂) production we used a PGE₂ EIA kit. To estimate protein levels and enzyme activities, we employed immunoblotting. Luciferase assays were used to examine nuclear transcription factor (NF)-κB activities.

RESULTS

Intragastric administration of Ac-EE (30 mg/kg) ameliorated HCl/EtOH-induced stomach tissue damages in SD rats. Ac-EE inhibited the levels of NO and PGE_2, down regulated mRNA and protein levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2. Ac-EE suppressed the nuclear level of NF-κB (p50), and inhibited NF-κB luciferase activity. The Phosphorylation of Akt and IκBα was also inhibited by Ac-EE both in vivo and in vitro.

CONCLUSION

Ac-EE treatment exerts an anti-gastritis effect in rats. Inhibition of the Akt/IκBα/NF-κB signaling pathway is associated with this effect, providing a pharmacological basis for the clinical application of the rhizome of A. chinensis in the treatment of inflammatory diseases.

Src Is a Prime Target Inhibited by Celtis choseniana Methanol Extract in Its Anti-Inflammatory Action

Celtis choseniana is the traditional plant used at Korea as a herbal medicine to ameliorate inflammatory responses. Although Celtis choseniana has been traditionally used as a herbal medicine at Korea, no systemic research has been conducted on its anti-inflammatory activity. Therefore, the present study explored an anti-inflammatory effect and its underlying molecular mechanism using Celtis choseniana methanol extract (Cc-ME) in macrophage-mediated inflammatory responses. In vitro anti-inflammatory activity of Cc-ME was evaluated using RAW264.7 cells and peritoneal macrophages stimulated by lipopolysaccharide (LPS), pam3CSK4 (Pam3), or poly(I:C). In vivo anti-inflammatory activity of Cc-ME was investigated using acute inflammatory disease mouse models, such as LPS-induced peritonitis and HCl/EtOH-induced gastritis. The molecular mechanism of Cc-ME-mediated anti-inflammatory activity was examined by Western blot analysis and immunoprecipitation using whole cell and nuclear fraction prepared from the LPS-stimulated RAW264.7 cells and HEK293 cells. Cc-ME inhibited NO production and mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), and tumor necrosis factor-alpha (TNF-α) in the RAW264.7 cells and peritoneal macrophages induced by LPS, pam3, or poly(I:C) without cytotoxicity. High-performance liquid chromatography (HPLC) analysis showed that Cc-ME contained anti-inflammatory flavonoids quercetin, luteolin, and kaempferol. Among those, the content of luteolin, which showed an inhibitory effect on NO production, was highest. Cc-ME suppressed the NF-κB signaling pathway by targeting Src and interrupting molecular interactions between Src and p85, its downstream kinase. Moreover, Cc-ME ameliorated the morphological finding of peritonitis and gastritis in the mouse disease models. Therefore, these results suggest that Cc-ME exerted in vitro and in vivo anti-inflammatory activity in LPS-stimulated macrophages and mouse models of acute inflammatory diseases. This anti-inflammatory activity of Cc-ME was dominantly mediated by targeting Src in NF-κB signaling pathway during macrophage-mediated inflammatory responses.

Photoaging protective effects of BIOGF1K, a compound-K-rich fraction prepared from Panax ginseng

BACKGROUND

BIOGF1K, a compound-K-rich fraction, has been shown to display anti-inflammatory activity. Although Panax ginseng is widely used for the prevention of photoaging events induced by UVB irradiation, the effect of BIOGF1K on photoaging has not yet been examined. In this study, we investigated the effects of BIOGF1K on UVB-induced photoaging events.

METHODS

We analyzed the ability of BIOGF1K to prevent UVB-induced apoptosis, enhance matrix metalloproteinase (MMP) expression, upregulate anti-inflammatory activity, reduce sirtuin 1 expression, and melanin production using reverse transcription-polymerase chain reaction, melanin content assay, tyrosinase assay, and flow cytometry. We also evaluated the effects of BIOGF1K on the activator protein-1 signaling pathway, which plays an important role in photoaging, by immunoblot analysis and luciferase reporter gene assays.

RESULTS

Treatment of UVB-irradiated NIH3T3 fibroblasts with BIOGF1K prevented UVB-induced cell death, inhibited apoptosis, suppressed morphological changes, reduced melanin secretion, restored the levels of type I procollagen and sirtuin 1, and prevented mRNA upregulation of MMP-1, MMP-2, and cyclo-oxygenase-2; these effects all occurred in a dose-dependent manner. In addition, BIOGF1K markedly reduced activator-protein-1-mediated luciferase activity and decreased the activity of mitogen-activated protein kinases (extracellular response kinase, p38, and C-Jun N-terminal kinase).

CONCLUSION

Our results strongly suggest that BIOGF1K has anti-photoaging activity and that BIOGF1K could be used in anti-aging cosmeceutical preparations.

Anti-inflammatory effect of torilidis fructus ethanol extract through inhibition of Src

CONTEXT

Torilidis fructus, fruits of Torilis japonica Decadolle (Umbelliferae), is a medicinal herb traditionally used as a pesticide, an astrictive, or a medicine for various inflammatory diseases.

OBJECTIVES

Due to the lack of pharmacological studies on this herbal medicine, we explored the inhibitory activity of torilidis fructus on the macrophage-mediated inflammatory response using its ethanol extract (Tf-EE).

MATERIAL AND METHODS

The Griess assay and prostaglandin (PGE₂) ELISA assay were conducted with Tf-EE (0-75 µg/mL) and LPS (1 µg/mL) treated RAW264.7 cells in cultured media. Tf-EE pretreated RAW264.7 cells were incubated with LPS for 6 h and semi-quantitative PCR was performed. Reporter gene assays, overexpression of target enzymes and immunoblotting were performed on macrophages to determine the molecular targets of Tf-EE.

RESULTS

Tf-EE markedly suppressed the inflammatory response of macrophages, such as lipopolysaccharide (LPS)-induced nitric oxide (NO) and PGE₂ production with IC₅₀ values of 35.66 and 62.47 µg/mL, respectively. It was also found that Tf-EE reduced the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 by 80%. Nuclear translocation and activation of nuclear factor (NF)-κB (p65 and p50) were declined by 60% and 30% respectively, and their regulatory events including the phosphorylation of AKT, IκBα, Src, and the formation of complexes between Src and p-p85 were also recognized to be diminished.

CONCLUSIONS

The signalling events managed by Src and p85 complex seemed to be critically involved in Tf-EE-mediated anti-inflammatory response. This might suggest that Tf-EE exhibited anti-inflammatory effects through Src-targeted inhibition of NF-κB.

Quercetin protects against atherosclerosis by inhibiting dendritic cell activation

SCOPE

Quercetin is a typical flavonol with atheroprotective effects, but the effect of quercetin on dendritic cell (DC) maturation in relation to atherosclerosis has not yet been clearly defined. Thus, we investigated whether quercetin can inhibit DC maturation and evaluated its potential value in atherosclerosis progression in ApoE^-/- mice.

METHODS AND RESULTS

Quercetin consumption inhibited DC activation, inflammatory response and suppressed the progression of atherosclerosis in ApoE^-/- mice. Subsequently, quercetin treatment inhibited the phenotypic and functional maturation of DCs, as evidenced not only by downregulation of CD80, CD86, MHC-II, IL-6 and IL-12 but also by a reduction in the ability to stimulate T cell allogeneic proliferation. Finally, an in vitro study demonstrated that quercetin inhibited DC maturation via upregulation of Dabs, which then downregulated the Src/PI3K/Akt-NF-κB-inflammatory pathways.

CONCLUSIONS

Our data indicate that quercetin attenuates atherosclerosis progression by regulating DC activation via Dab2 protein expression.

JS-III-49, a hydroquinone derivative, exerts anti-inflammatory activity by targeting Akt and p38

Since previous studies have reported that hydroquinone (HQ) exerted immunosuppressive and anti-inflammatory activity, various HQ derivatives have been synthesized and their biological activities investigated. In this study, we explored the anti-inflammatory activity of JS-III-49, a novel HQ derivative, in macrophage-mediated inflammatory responses. JS-III-49 suppressed the production of the inflammatory mediators nitric oxide (NO) and prostaglandin E₂ (PGE₂) and down-regulated the mRNA expression of the inflammatory enzymes cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) as well as the expression of the pro-inflammatory cytokines interleukin-6 (IL-6) and IL-1b without cytotoxicity in LPS-stimulated RAW264.7 cells. JS-III-49 inhibited nuclear translocation of the NF-kB transcription factors p65 and p50 by directly targeting Akt, an upstream kinase of the NF-kB pathway, in LPS-stimulated RAW264.7 cells. However, JS-III-49 did not directly inhibit the kinase activities of Src and Syk, which are upstream kinases of Akt, in LPS-stimulated RAW264.7 cells. Moreover, JS-III-49 suppressed the nuclear translocation of c-Fos, one of the components of AP-1, by specifically targeting p38, an upstream mitogen-activated protein kinase (MAPK) in the AP-1 pathway in LPS-stimulated RAW264.7 cells. These results suggest that JS-III-49 plays an anti-inflammatory role in LPS-stimulated macrophages by targeting Akt and p38 in the NF-kB and AP-1 pathways, respectively.

The therapeutic effects of Periploca forrestii Schltr. Stem extracts on collagen-induced arthritis by inhibiting the activation of Src/NF-κB signaling pathway in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Periploca forrestii Schltr. is a classical traditional Chinese medicine (TCM) called Heilonggu (HLG) in China. According to the theory of TCM, it possesses the efficacy of eliminating wind and removing dampness. In clinical practice, it is commonly used for the treatment of rheumatoid arthritis. The present work aimed to evaluate the anti-rheumatism activity of HLG ethanol extract and reveal the underlying molecular mechanism by employing an animal model of collagen-induced rheumatoid arthritis (CIA) in rats.

MATERIALS AND METHODS

The CIA was induced in male Sprague-Dawley rats by intradermal injection of bovine collagen-II in complete Freund's adjuvant (CFA) at the base of tail. The rats received oral administration of HLG (200 and 400mg/kg) from day 1, with the treatment lasting for 28 days. A variety of indicators were measured for evaluation of anti-rheumatism effect, including paw swelling, arthritis scores, and histopathological changes. Furthermore, the serum levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and prostaglandin E2 (PGE2), as well as cyclooxygenase-2 (COX-2), nuclear factor NF-κB p65 and Src kinase in joint synovial tissues were detected to explore the possible mechanisms.

RESULTS

The administration of HLG significantly restored type II collagen-induced arthritis in rats as evidenced by decrease in paw swelling and inflammatory factors in serum. Meanwhile, this treatment also notably reduced NF-κB p65 and COX-2 expression. Surprisingly, the activity of Src kinase was also inhibited demonstrated by downregulation of phosphorylated Src.

CONCLUSION

Our results revealed that HLG possessed observable therapeutic action on collagen-induced arthritis by inhibiting the activation of Src and nuclear translocation of NF-κB in rats. HLG may serve as a potential candidate for the management of patients with RA.

Src/Syk-Targeted Anti-Inflammatory Actions of Triterpenoidal Saponins from Gac (Momordica cochinchinensis) Seeds

Momordica cochinchinensis Spreng (family Cucurbitaceae), also known as gac, or red melon, is an edible Southeast Asian fruit valued for its nutritional and medicinal properties. Specifically, Momordicae Semen, the seeds of the gac fruit, is used in traditional Chinese medicine to treat boils, rheumatic pain, muscle spasm, hemorrhoids, and hemangiomas. In this study, a chemical investigation into a gac seed ethanol (EtOH) extract resulted in the identification of three triterpenoidal saponins (1-3), which were investigated for their anti-inflammatory effects. Among the saponins, momordica saponin I (compound 3) reduced the production of nitric oxide (NO) in LPS-activated RAW264.7 cells without inducing cytotoxicity. The mRNA levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 were decreased by momordica saponin I. Additionally, the translocation of p65 and p50 (subunits of the transcription factor NF-[Formula: see text]B) into the nucleus was remarkably inhibited. Furthermore, the phosphorylation levels of inflammatory signaling proteins (I[Formula: see text]B[Formula: see text], Src, and Syk) known to be upstream regulatory molecules of p65 were decreased under momordica saponin I-treated conditions. The molecular targets of momordica saponin I were confirmed in overexpression experiments and through immunoblot analyses with Src and Syk. This study provides evidence that momordica saponin I could be beneficial in treating inflammatory diseases, and should be considered a bioactive immunomodulatory agent with anti-inflammatory properties.

The effects of Qi Teng Xiao Zhuo granules, traditional Chinese medicine, on the expression of genes in chronic glomerulonephritis rats

BACKGROUND AND AIM

Chronic glomerulonephritis (CGN) is a primary glomerular disease that is related to immune-mediated inflammatory diseases. Qi Teng Xiao Zhuo granules have been proposed as a prescription of traditional Chinese medicine for treatment of CGN, but the comprehensive molecular mechanism underlying this therapeutic effect is not clear to date. The aim of this study was to evaluate and analyze the possible roles and molecular mechanisms of Qi Teng Xiao Zhuo granule-mediated treatment of CGN induced by adriamycin in rats.

METHODS

For gene expression analysis, four samples of glomerular tissue from rats in the Qi Teng Xiao Zhuo granule group and four samples each from the adriamycin treated and control groups were hybridized with Agilent Rat 4×44K whole genome microarrays. KEGG and Gene Ontology (GO) analyses and LIMMA, String and Cytoscape software were used to analyze the functional microarray data and screen differentially expressed genes. Hub genes were identified using Pathway Studio software. Real-time PCR was performed to verify the selected genes.

RESULTS

Microarray gene expression analysis showed that Pnoc, Cacfd1, Fos, Igll1, Lcn2, and Syk were among the most downregulated genes in the Qi Teng Xiao Zhuo granule group compared with the adriamycin treated group, whereas Cyp2c7, Hsd3b6, Acsm5, and Ugt2b15 were significantly upregulated. Functional analysis demonstrated that metabolism of xenobiotics by cytochrome P450, the B cell receptor signaling pathway, and cytokine-cytokine receptor interaction pathways were significantly downregulated in the Qi Teng Xiao Zhuo granule group and that GO terms related to positive regulation of immune response, immune response-activating signal transduction, cell differentiation, cell cycle, proliferation, and adhesion were significantly affected. Fos and Syk were considered to be potential hub genes.

CONCLUSIONS

In the adriamycin-induced CGN rat model, comprehensive molecular mechanisms were involved with complex gene expression alterations containing many altered pathways and GO terms. However, how Qi Teng Xiao Zhuo granules regulate these events warrants further investigation.

Role of Antioxidants and Natural Products in Inflammation

Inflammation is a comprehensive array of physiological response to a foreign organism, including human pathogens, dust particles, and viruses. Inflammations are mainly divided into acute and chronic inflammation depending on various inflammatory processes and cellular mechanisms. Recent investigations have clarified that inflammation is a major factor for the progression of various chronic diseases/disorders, including diabetes, cancer, cardiovascular diseases, eye disorders, arthritis, obesity, autoimmune diseases, and inflammatory bowel disease. Free radical productions from different biological and environmental sources are due to an imbalance of natural antioxidants which further leads to various inflammatory associated diseases. In this review article, we have outlined the inflammatory process and its cellular mechanisms involved in the progression of various chronic modern human diseases. In addition, we have discussed the role of free radicals-induced tissue damage, antioxidant defence, and molecular mechanisms in chronic inflammatory diseases/disorders. The systematic knowledge regarding the role of inflammation and its associated adverse effects can provide a clear understanding in the development of innovative therapeutic targets from natural sources that are intended for suppression of various chronic inflammations associated diseases.

PDK1 in NF-κB signaling is a target of Xanthium strumarium methanolic extract-mediated anti-inflammatory activities

ETHNOPHARMACOLOGICAL RELEVANCE

Xanthium strumarium L. (Asteraceae) has traditionally been used to treat bacterial infections, nasal sinusitis, urticaria, arthritis, chronic bronchitis and rhinitis, allergic rhinitis, edema, lumbago, and other ailments. However, the molecular mechanisms by which this plant exerts its anti-inflammatory effects are poorly characterized. Here we studied the immunopharmacological activities of the methanolic extract of the aerial parts of this plant (Xs-ME) and validated its pharmacological targets.

MATERIALS AND METHODS

To evaluate the anti-inflammatory activity of Xs-ME, we employed lipopolysaccharide (LPS)-treated macrophages and an HCl/EtOH-induced mouse model of gastritis. We also used HPLC to identify the potentially active anti-inflammatory components of this extract. The molecular mechanisms of its anti-inflammatory activity were studied by kinase assays, reporter gene assays, immunoprecipitation analysis, and overexpression of target enzymes.

RESULTS

The production of nitric oxide (NO) and prostaglandin E2 (PGE2) were both suppressed by Xs-ME. Moreover, orally administered Xs-ME ameliorated HCl/EtOH-induced gastric lesions. Furthermore, this extract downregulated the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 and reduced the nuclear levels of NF-κB. Signaling events upstream of NF-κB translocation, such as phosphorylation of AKT and the formation of PDK1-AKT signaling complexes, were also inhibited by Xs-ME. Moreover, Xs-ME suppressed the enzymatic activity of PDK1. Additionally, PDK1-induced luciferase activity and Akt phosphorylation were both inhibited by Xs-ME. We also identified the polyphenol resveratrol as a likely active anti-inflammatory component in Xs-ME that targets PDK1.

CONCLUSION

Xs-ME exerts anti-inflammatory activity in vitro and in vivo by inhibiting PDK1 kinase activity and blocking signaling to its downstream transcription factor, NF-κB.

In vitro antioxidative and anti-inflammatory effects of the compound K-rich fraction BIOGF1K, prepared from Panax ginseng

Background

BIOGF1K, a compound K-rich fraction prepared from the root of Panax ginseng, is widely used for cosmetic purposes in Korea. We investigated the functional mechanisms of the anti-inflammatory and antioxidative activities of BIOGF1K by discovering target enzymes through various molecular studies.

Methods

We explored the inhibitory mechanisms of BIOGF1K using lipopolysaccharide-mediated inflammatory responses, reporter gene assays involving overexpression of toll-like receptor adaptor molecules, and immunoblotting analysis. We used the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay to measure the antioxidative activity. We cotransfected adaptor molecules, including the myeloid differentiation primary response gene 88 (MyD88) and Toll/interleukin-receptor domain containing adaptor molecule-inducing interferon-β (TRIF), to measure the activation of nuclear factor (NF)-κB and interferon regulatory factor 3 (IRF3).

Results

BIOGF1K suppressed lipopolysaccharide-triggered NO release in macrophages as well as DPPH-induced electron-donating activity. It also blocked lipopolysaccharide-induced mRNA levels of interferon-β and inducible nitric oxide synthase. Moreover, BIOGF1K diminished the translocation and activation of IRF3 and NF-κB (p50 and p65). This extract inhibited the upregulation of NF-κB-linked luciferase activity provoked by phorbal-12-myristate-13 acetate as well as MyD88, TRIF, and inhibitor of κB (IκBα) kinase (IKKβ), and IRF3-mediated luciferase activity induced by TRIF and TANK-binding kinase 1 (TBK1). Finally, BIOGF1K downregulated the NF-κB pathway by blocking IKKβ and the IRF3 pathway by inhibiting TBK1, according to reporter gene assays, immunoblotting analysis, and an AKT/IKKβ/TBK1 overexpression strategy.

Conclusion

Overall, our data suggest that the suppression of IKKβ and TBK1, which mediate transcriptional regulation of NF-κB and IRF3, respectively, may contribute to the broad-spectrum inhibitory activity of BIOGF1K.

Vanillin abrogates ethanol induced gastric injury in rats via modulation of gastric secretion, oxidative stress and inflammation

Vanillin is commonly used as an additive in food, medicine and cosmetics, but its effect has not yet been studied in gastric injury. Therefore the effect of vanillin was studied in experimental gastric ulcer. Gastric secretion and acidity were studied in pylorus ligated rats. Ulcer index, levels of gastric mucus, malondialdehyde (MDA), myeloperoxidase activity (MPO), expression of nuclear factor kappa B (NF-κB) p65, and histopathological changes were determined in ethanol induced gastric ulcer. Pre treatment with vanillin significantly reduced gastric secretion (P < 0.001) and acidity (P < 0.0001) and gastric ulcer index scores (P < 0.001). and augmented the gastric mucosal defense. Vanillin significantly restored the depleted gastric wall mucus levels (P < 0.0001) induced by ethanol and also significantly attenuated ethanol induced inflammation and oxidative stress by the suppression of gastric MPO activity (P < 0.001), reducing the expression of NF-κB p65 and the increased MDA levels (P < 0.001). Vanillin was also effective in alleviating the damage to the histological architecture and the activation of mast cells induced by ethanol.

Together the results of this study highlight the gastroprotective activity of vanillin in gastric ulcers of rats through multiple actions that include inhibition of gastric secretion and acidity, reduction of inflammation and oxidative stress, suppression of expression of NF-κB, and restoration of the histological architecture.

AP-1-Targeted Inhibition of Macrophage Function and Lipopolysaccharide/D-Galactosamine-Induced Hepatitis by Phyllanthus acidus Methanolic Extract

Traditionally, Phyllanthus acidus (Phyllanthaceae) has been used for the treatment of rheumatism, bronchitis, asthma, respiratory disorders, and hepatitis. Recently, we showed that a methanol extract of Phyllanthaceae (Pa-ME) has a potent anti-inflammatory activity in RAW264.7 cells and strongly ameliorates HCl / EtOH -induced gastric ulcers in mice by targeting the Src/Syk of NF-κB. In the present study, we explored the molecular mechanism of Pa-ME on the AP-1 activation pathway and evaluated its potential hepatoprotective effects. To do this, we employed lipopolysaccharide (LPS)-stimulated RAW264.7 cells and U937 cells and an LPS/D-galactosamine (D- GaIN )-induced acute hepatitis mouse model. We utilized a multitude of assays, including immunoblotting analysis, reporter gene assays, and mRNA expression analysis, to determine the effect of Pa-ME on the AP-1 pathway. Pa-ME strikingly suppressed the production of LPS-induced pro-inflammatory cytokines including interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α). Furthermore, Pa-ME also strongly inhibited activator protein-1 (AP-1) activation and mitogen-activated protein kinase (MAPK) phosphorylation in LPS-stimulated RAW264.7 macrophages cells and the U937 monocyte like human cell line. Moreover, pre-treatment with Pa-ME exhibited strong hepatoprotective and curative effects in an LPS/D-Gal-induced mouse hepatitis model as evidenced by a decrease in elevated serum AST and ALT levels and the amelioration of histological damage. Taken together, our data suggest that Pa-ME might play a crucial ethnopharmacological role as a hepatoprotective herbal remedy by suppressing MAPK signaling and the activity of the downstream transcription factor AP-1.

ATP-Binding Pocket-Targeted Suppression of Src and Syk by Luteolin Contributes to Its Anti-Inflammatory Action

Luteolin is a flavonoid identified as a major anti-inflammatory component of Artemisia asiatica. Numerous reports have demonstrated the ability of luteolin to suppress inflammation in a variety of inflammatory conditions. However, its exact anti-inflammatory mechanism has not been fully elucidated. In the present study, the anti-inflammatory mode of action in activated macrophages of luteolin from Artemisia asiatica was examined by employing immunoblotting analysis, a luciferase reporter gene assay, enzyme assays, and an overexpression strategy. Luteolin dose-dependently inhibited the secretion of nitric oxide (NO) and prostaglandin E₂ (PGE₂) and diminished the levels of mRNA transcripts of inducible NO synthase (iNOS), tumor necrosis factor- (TNF-) α, and cyclooxygenase-2 (COX-2) in lipopolysaccharide- (LPS-) and pam3CSK-treated macrophage-like RAW264.7 cells without displaying cytotoxicity. Luteolin displayed potent NO-inhibitory activity and also suppressed the nuclear translocation of NF-κB (p65 and p50) via blockade of Src and Syk, but not other mitogen-activated kinases. Overexpression of wild type Src and point mutants thereof, and molecular modelling studies, suggest that the ATP-binding pocket may be the luteolin-binding site in Src. These results strongly suggest that luteolin may exert its anti-inflammatory action by suppressing the NF-κB signaling cascade via blockade of ATP binding in Src and Syk.

AP-1-Targeting Anti-Inflammatory Activity of the Methanolic Extract of Persicaria chinensis

In traditional Chinese medicine, Persicaria chinensis L. has been prescribed to cure numerous inflammatory disorders. We previously analyzed the bioactivity of the methanol extract of this plant (Pc-ME) against LPS-induced NO and PGE2 in RAW264.7 macrophages and found that it prevented HCl/EtOH-induced gastric ulcers in mice. The purpose of the current study was to explore the molecular mechanism by which Pc-ME inhibits activator protein- (AP-) 1 activation pathway and mediates its hepatoprotective activity. To investigate the putative therapeutic properties of Pc-ME against AP-1-mediated inflammation and hepatotoxicity, lipopolysaccharide- (LPS-) stimulated RAW264.7 and U937 cells, a monocyte-like human cell line, and an LPS/D-galactosamine- (D-GalN-) induced acute hepatitis mouse model were employed. The expression of LPS-induced proinflammatory cytokines including interleukin- (IL-) 1β, IL-6, and tumor necrosis factor-α (TNF-α) was significantly diminished by Pc-ME. Moreover, Pc-ME reduced AP-1 activation and mitogen-activated protein kinase (MAPK) phosphorylation in both LPS-stimulated RAW264.7 cells and differentiated U937 cells. Additionally, we highlighted the hepatoprotective and curative effects of Pc-ME pretreated orally in a mouse model of LPS/D-GalN-intoxicated acute liver injury by demonstrating the significant reduction in elevated serum AST and ALT levels and histological damage. Therefore, these results strongly suggest that Pc-ME could function as an antihepatitis remedy suppressing MAPK/AP-1-mediated inflammatory events.