Avicularin Inhibits Lipopolysaccharide-Induced Inflammatory Response by Suppressing ERK Phosphorylation in RAW 264.7 Macrophages

Protective effect of avicularin against lung cancer via inhibiting inflammation, oxidative stress, and induction of apoptosis: an in vitro and in vivo study

The purpose of this research was to investigate whether or not avicularin (AVL) possesses any anticancer properties when tested against lung cancer. In the beginning, the effect that it had on the cellular viability of A549 cells was investigated, and it was discovered that AVL has a considerable negative impact on cellular viability. Following that, an investigation using flow cytometry was carried out to investigate its function in the process of apoptosis and the cell cycle of A549 cells. It has been discovered that AVL significantly promotes apoptosis and stops the cell cycle at the G2/M phase. The colony-forming capacity of A549 cells was observed to be greatly suppressed as the AVL concentration increased compared to the group that received no treatment. In addition to this, the benzo(a)pyrene in vivo model was established in order to investigate the pharmacological value of AVL. The findings revealed that AVL greatly prevented the formation of pro-inflammatory cytokines, in addition to the reduction in oxidative stress, which was evidenced by a reduction in the concentration of TNF-α, IL-1β, IL-6, and MDA with an improvement in the concentration of SOD and GPx, respectively. Our results successfully demonstrated the pharmacological benefit of avicularin against lung cancer, and it has been suggested that it showed a multifactorial effect.

Quantitative proteomics and metabolomics analysis reveals the response mechanism of alfalfa (Medicago sativa L.) to o-coumaric acid stress

O-coumaric acid (OCA), as a significant phenolic allelochemical found in hairy vetch (Vicia villosa Roth.), that can hinder the growth of alfalfa (Medicago sativa L.), particularly the growth of alfalfa roots. Nonetheless, the mechanism by which OCA inhibits alfalfa root growth remains unclear. In this study, a liquid chromatography tandem mass spectrometry (LC-MS/MS)-based quantitative proteomics analysis was carried out to identify differentially accumulated proteins (DAPs) under OCA treatment. The findings indicated that 680 proteins were DAPs in comparison to the control group. Of those, 333 proteins were up-regulated while 347 proteins were down-regulated. The enrichment analysis unveiled the significance of these DAPs in multiple biological and molecular processes, particularly in ribosome, phenylpropanoid biosynthesis, glutathione metabolism, glycolysis/gluconeogenesis and flavonoid biosynthesis. The majority of DAPs reside in the cytoplasm (36.62%), nucleus (20.59%) and extracellular space (14.12%). In addition, phenylalanine deaminase was identified as a potential chemical-induced regulation target associated with plant lignin formation. DAPs were mainly enriched in flavonoid biosynthesis pathways, which were related to plant root size. Using the UPLC-ESI-MS/MS technique and database, a total of 87 flavonoid metabolites were discovered. The metabolites were predominantly enriched for biosynthesizing naringenin chalcone, which was linked to plant lignin formation, aligning with the enrichment outcomes of DAPs. Consequently, it was deduced that OCA impacted the structure of cell walls by mediating the synthesis of lignin in alfalfa roots, subsequently inducing wilt. Furthermore, a range of proteins have been identified as potential candidates for the breeding of alfalfa strains with enhanced stress tolerance.

Aromadendrin inhibits PMA-induced cytokine formation/NF-κB activation in A549 cells and ovalbumin-induced bronchial inflammation in mice

Hyperproduction of immune cell-derived inflammatory molecules and recruitment of immune cells promote the development of allergic asthma (AA). Aromadendrin (ARO) has various biological properties including anti-inflammatory effects. In this study, we evaluated the ameliorative effects of ARO on the development of AA in vitro and in vivo. Phorbol 12-myristate 13-acetate (PMA, 100 nM) was used to induce inflammation in A549 airway epithelial cells. The cohesion of A549 and eosinophil EOL-1 cells was studied. Ovalbumin (30 or 60 μg)/Alum (3 mg) mixture was adapted for AA induction in mice. ARO (5 or 10 mg/kg, p. o.) was administered to mice to investigate its ameliorative effect on AA development. Enzyme-linked immunosorbent assay, western blotting, and hematoxylin and eosin/periodic acid Schiff staining were performed to study the ameliorative effect of ARO on bronchial inflammation. In PMA-stimulated A549 cells, the upregulation of cytokines (interleukin [IL]-1β/IL-6/tumor necrosis factor alpha [TNF-α]/monocyte chemoattractant protein [MCP]-1]) and nuclear factor kappa B (NF-κB) activation was effectively reduced by ARO pretreatment. ARO suppressed the adhesion of A549 cells and eosinophils. In ovalbumin-induced AA mice, the levels of cells, such as eosinophils, Th2 cytokines, MCP-1 in bronchoalveolar lavage fluid, IgE in serum, and inducible nitric oxide synthase/cyclooxygenase-2 expression in the lung tissue were upregulated, which were all suppressed by ARO. In addition, the increase in cell inflow and mucus formation in the lungs of AA mice was reversed by ARO as per histological analysis. ARO also modulated NF-κB activation in the lungs of AA mice. Overall, the anti-inflammatory properties of ARO in vitro/in vivo studies of AA were notable. Thus, ARO has a modulatory effect on bronchial inflammation and may be a potential adjuvant for AA treatment.

Avicularin alleviates acute liver failure by regulation of the TLR4/MyD88/NF-κB and Nrf2/HO-1/GPX4 pathways to reduce inflammation and ferroptosis

Acute liver failure (ALF) is an inflammation-mediated hepatocyte death process associated with ferroptosis. Avicularin (AL), a Chinese herbal medicine, exerts anti-inflammatory and antioxidative effects. However, the protective effect of AL and the mechanism on ALF have not been reported. Our in vivo results suggest that AL significantly alleviated lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced hepatic pathological injury, liver enzymes, inflammatory cytokines, reactive oxygen species and iron levels and increased the antioxidant enzyme activities (malondialdehyde and glutathione). Our further in vitro experiments demonstrated that AL suppressed inflammatory response in LPS-stimulated RAW 264.7 cells via blocking the toll-like receptor 4 (TLR4)/myeloid differentiation protein-88 (MyD88)/nuclear factor kappa B (NF-κB) pathway. Moreover, AL attenuated ferroptosis in D-GalN-induced HepG2 cells by activating the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1)/glutathione peroxidase 4 (GPX4) pathway. Therefore, AL can alleviate inflammatory response and ferroptosis in LPS/D-GalN-induced ALF, and its protective effects are associated with blocking TLR4/MyD88/NF-κB pathway and activating Nrf2/HO-1/GPX4 pathway. Moreover, AL is a promising therapeutic option for ALF and should be clinically explored.

Flavonols in Action: Targeting Oxidative Stress and Neuroinflammation in Major Depressive Disorder

Major depressive disorder is one of the most common mental illnesses that highly impairs quality of life. Pharmacological interventions are mainly focused on altered monoamine neurotransmission, which is considered the primary event underlying the disease's etiology. However, many other neuropathological mechanisms that contribute to the disease's progression and clinical symptoms have been identified. These include oxidative stress, neuroinflammation, hippocampal atrophy, reduced synaptic plasticity and neurogenesis, the depletion of neurotrophic factors, and the dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis. Current therapeutic options are often unsatisfactory and associated with adverse effects. This review highlights the most relevant findings concerning the role of flavonols, a ubiquitous class of flavonoids in the human diet, as potential antidepressant agents. In general, flavonols are considered to be both an effective and safe therapeutic option in the management of depression, which is largely based on their prominent antioxidative and anti-inflammatory effects. Moreover, preclinical studies have provided evidence that they are capable of restoring the neuroendocrine control of the HPA axis, promoting neurogenesis, and alleviating depressive-like behavior. Although these findings are promising, they are still far from being implemented in clinical practice. Hence, further studies are needed to more comprehensively evaluate the potential of flavonols with respect to the improvement of clinical signs of depression.

Avicularin alleviates osteoporosis-induced implant loosening by attenuating macrophage M1 polarization via its inhibitory effect on the activation of NF-κB

Currently, the failure rate for internal fixation in patients with osteoporosis can be reduced by antiosteoporosis therapy alone. However, the administration of anti-osteoporotic drugs is not a complete solution. Therefore, it is necessary to investigate other causes of surgical failure, such as inflammation. In recent years, the inflammation caused by macrophage M1 polarization has garnered wide attention. The purpose of this research is to explore the inhibitory effect of avicularin (AL) on macrophage M1 polarization, by which it ameliorates inflammation, thus alleviating implant instability. We established an osteoporosis mouse model of implant loosening. The mouse tissues were taken out for morphological analysis, staining analysis and bone metabolic index analysis. In in vitro experiments, bone marrow derived macrophages (BMDM) and RAW264.7 cells were polarized to M1 macrophages using lipopolysaccharide (LPS), and analyzed by immunofluorescence (IF) staining, Western blot (WB) and flow cytometry. WB was also used to analyze the nuclear factor kappa-B (NF-κB) pathway. In addition, the expression levels of inflammatory cytokines were detected in cell supernatant using ELISA kits. Through observation of this experiments, we found that AL can inhibit M1 polarization of macrophages. Moreover, it can significantly inhibit the release of inflammatory factors to improve multiple mouse femur parameters. Furthermore, AL inhibited the phosphorylation of IKBα and P65 in the NF-κB pathway. The above data indicate that AL ameliorates inflammatory responses by inhibiting macrophage M1 polarization via its inhibitory effect on the NF-κB pathway, thus alleviating the instability of implants in mice with osteoporosis.

Avicularin Alleviates Osteoporosis in Ovariectomized Mice by Inhibiting Osteoclastogenesis through NF-κB Pathway Inhibition

Osteoporosis (OP) is mainly manifested by bone loss and bone degeneration. OP is considered a risk factor for pathological fractures, as well as impacts the health of middle-aged and elderly individuals. Drug therapy remains the main treatment scheme for OP; however, its efficacy is limited and has been associated with serious side effects. Therefore, it is important to develop new, effective, and safe treatment methods for OP. Avicularin (AL) is a flavonoid and quercetin derivative from various plants. Our study showed that AL disrupts osteoclast activation and resorptive function via inhibition of the RANKL-induced osteoclast differentiation together with the resorption capacity of bone marrow-derived macrophages (BMMs). Hence, AL prevents the activation and resorptive activity of osteoclasts. The results of qPCR showed that genes related to osteoclasts exhibited downregulated expression after AL treatment. Furthermore, AL inhibited RANKL-induced phosphorylation as well as degradation of the inhibitor IκBα of the NF-κB pathway, together with P65 phosphorylation in BMMs. We used an OP mouse model that was established by ovariectomy (OVX). Relative to untreated OP mice, mice that received AL treatment showed a significant increase in bone mineral density; however, the expression of TRAP, NFATC1, mmp9, and CTX-1 was significantly reduced. These results indicate that AL disrupts osteoclastogenesis via inhibition of the NF-κB pathway, which in turn improves OVX-induced OP.

Virtual Screening of Soybean Protein Isolate-Binding Phytochemicals and Interaction Characterization

Soybean protein isolate (SPI) and small molecule interactions have drawn more and more attention regarding their benefits for both parts, while research on large-scale investigations and comparisons of different compounds is absent. In this study, a high throughput virtual screening was applied on a phytochemical database with 1130 compounds to pinpoint the potential SPI binder. Pentagalloylglucose, narcissoside, poliumoside, isoginkgetin, and avicurin were selected as the top-five ranking molecules for further validation. Fluorescence quenching assays illustrated that isoginkgetin has a significantly higher apparent binding constant (Ka) of (0.060 ± 0.020) × 10⁶ L·mol^-1, followed by avicularin ((0.058 ± 0.010) × 10⁶ L·mol^-1), pentagalloylglucose ((0.049 ± 0.010) × 10⁶ L·mol^-1), narcissoside ((0.0013 ± 0.0004) × 10⁶ L·mol^-1), and poliumoside ((0.0012 ± 0.0006) × 10⁶ L·mol^-1). Interface characterization by MD simulation showed that protein residues E172, H173, G202, and V204 are highly involved in hydrogen bonding with the two carbonyl oxygens of isoginketin, which could be the crucial events in SPI binding. Van der Waals force was identified as the major driven force for isoginketin binding. Our study explored SPI-phytochemical interaction through multiple strategies, revealing the molecular binding details of isoginkgetin as a novel SPI binder, which has important implications for the utilization of the SPI-phytochemical complex in food applications.

Elsholtzia: A genus with antibacterial, antiviral, and anti-inflammatory advantages

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Elsholtzia (family Labiaceae) is an important source of folk traditional Chinese medicine, mainly used to relieve the symptoms of cold, fever, pneumonia and so on. However, currently available data on its traditional and pharmacological advantages have not been comprehensively reviewed.

AIM OF THE REVIEW

This review provides up-to-date and comprehensive information on the ethnopharmacological, phytochemical, pharmacological properties and toxicity of Elsholtzia, highlights the antibacterial, antiviral, and anti-inflammatory advantages of the genus, and explores its therapeutic potential.

MATERIALS AND METHODS

Use Google Scholar, Scifinder, PubMed, Springer, Elsevier, Wiley, Web of Science and other online database search to collect the research literatures on application, chemistry and biological activity of Elsholtzia published before December 2021. Their scientific names have been verified using The Plant List and World Flora Online websites.

RESULTS

A total of 42 species of Elsholtzia are widely distributed all over the world, especially in Yunnan Province (China). Since Elsholtzia genus is commonly used in the folk to treat respiratory infectious diseases such as cold and fever, growing numbers of studies have confirmed their antiviral, antibacterial and anti-inflammatory activities. So far, about 221 non-volatile compounds and 1008 volatile compounds have been identified from Elsholtzia plants, mainly containing flavonoids and terpenoids showing convincing antibacterial, antiviral and anti-inflammatory activities. Further research found that their antibacterial and antiviral spectrums are broad, and volatile oils are considered to be the main antibacterial components. Their anti-inflammatory mechanism is mainly through the inhibition of NF-κB and MAPKs signaling pathways. Toxicological studies have not established its toxicity.

CONCLUSIONS

By summarizing the latest information on genus Elsholtzia, their traditional uses, material basis and mechanisms of action in antiviral, antibacterial and anti-inflammatory aspects were described, providing new insights for the genus and its importance as a potential natural resource of antiviral and anti-inflammatory drugs, giving evidence and new ideas for the development of herbal medicines.

Antidepressant Potential of Quercetin and its Glycoside Derivatives: A Comprehensive Review and Update

Depression is a global health problem with growing prevalence rates and serious impacts on the daily life of patients. However, the side effects of currently used antidepressants greatly reduce the compliance of patients. Quercetin is a flavonol present in fruits, vegetables, and Traditional Chinese medicine (TCM) that has been proved to have various pharmacological effects such as anti-depressant, anti-cancer, antibacterial, antioxidant, anti-inflammatory, and neuroprotective. This review summarizes the evidence for the pharmacological application of quercetin to treat depression. We clarified the mechanisms of quercetin regulating the levels of neurotransmitters, promoting the regeneration of hippocampal neurons, improving hypothalamic-pituitary-adrenal (HPA) axis dysfunction, and reducing inflammatory states and anti-oxidative stress. We also summarized the antidepressant effects of some quercetin glycoside derivatives to provide a reference for further research and clinical application.

Health Benefits of Avicularin in the Medicine Against Cancerous Disorders and other Complications: Biological Importance, Therapeutic Benefit and Analytical Aspects

Background:

Herbal drugs and their derived phytochemicals have been used in medicine for the preparation of different types of pharmaceutical products. Pure phytochemicals including flavonoids, alkaloids and terpenoids have been used in medicine for the treatment of different types of human disorders including cancerous disorders. Flavonoids have been well known in medicine for their anti-viral, anti-bacterial, anti-inflammatory, anti-diabetic, anti-cancer, anti-aging and cardioprotective potential. Avicularin, also called quercetin-3-α-l-arabino furanoside, is a pure flavonoid, a class of phytochemicals, found to be present in Lindera erythrocarpa and Lespedeza cuneata. Avicularin has been well known in medicine for its anti-cancer properties.

Methods:

In the present work, scientific data of avicularin have been collected from different databases such as Google, PubMed, Science Direct, Google Scholar and Scopus and summarized with reference to medicinal importance, pharmacological activities and analytical aspects of avicularin. The present review summarized the health beneficial properties of avicularin in medicine through data analysis of various scientific research works. Further analytical progress in medicine for the qualitative and quantitative analysis of avicularin in medicine has been also discussed in the present work.

Results:

Scientific data analysis of different literature work revealed the biological importance of flavonoid class of phytochemical ‘avicularin’ in medicine. Scientific data analysis revealed that avicularin was found to be present in the Lindera erythrocarpa, Lespedeza cuneata, Rhododendron schlipenbachii and Psidium guajava. Avicularin has been well known in medicine for its anti-inflammatory, anti-allergic, anti-oxidant, anti-tumor and hepatoprotective activities. Avicularin protects cardiomyocytes and hepatocytes against oxidative stress-induced apoptosis and induces cytotoxicity in cancer lines and tumor tissues. Avicularin has positive influence on human hepatocellular carcinoma and inhibits intracellular lipid accumulation. The role of avicularin in rheumatoid arthritis has been also established with its underlying molecular mechanisms in the scientific work. Recent interest in avicularin has focused on pharmacological investigations for its anti-cancer activity in the medicine.

Conclusion:

The present work signified the biological importance of avicularin in medicine through its medicinal uses, pharmacological activities and analytical aspects in the biological system.

Avicularin Attenuates Memory Impairment in Rats with Amyloid Beta-Induced Alzheimer's Disease

Amyloid-beta-induced Alzheimer's disease (AD) and its further complications are well-established models in preclinical studies and demonstrated by many researchers. Intracerebroventricular injection of Aβ produces brain malfunction, including neurodegeneration and memory impairment. Avicularin is a bioactive flavonoid that has been found to prevent oxidative stress and proinflammatory cytokines. Alzheimer's disease treatment may benefit from inhibiting amyloid-beta and its related complications. Hence, by considering multiple actions of avicularin, including antioxidant and anti-inflammatory, we demonstrated the neuroprotective action of avicularin against amyloid beta-induced neurotoxicity. Aβ_1-42 (1 µg/µl) was dissolved in phosphate buffer solution (pH7.4) and incubated at 37 °C for 3 days to induce aggregation. A single intracerebroventricular (i.c.v.) injection of the Aβ_1-42 was given to the animals utilizing stereotaxic equipment. Avicularin was dissolved in 0.5% sodium carboxymethyl cellulose (CMC), and treatment was given to the animals for 21 days at a dose of (25, 50, and 100 mg/kg, p.o.) after Aβ_1-42 peptide (i.c.v.) injection. Several behavioral studies, acetylcholinesterase activity, oxidative stress, TNFα, IL-6, IL-1β, and expression of BDNF and amyloid-beta were measured. Avicularin treatment (50 and 100 mg/kg) showed cognition enhancement activity in behavioral studies and could reverse the effects of amyloid beta-induced inflammatory response and excessive oxidative stress. Furthermore, the findings reveal that avicularin can halt AD progression by targeting BDNF and amyloid-beta levels in the brain, suggesting that avicularin could be used for Alzheimer's disease treatment.

Oxymatrine hydrazone (OMTH) synthesis and its protective effect for rheumatoid arthritis through downregulation of MEK/NF-κB pathway

Rheumatoid arthritis (RA) is one of the inflammatory diseases detected in more than 1% of the world population. In the present study, oxymatrine hydrazone (OMTH) was synthesized and investigated for treatment of RA in vitro in TNF-α induced fibroblast-like synoviocyte cell model. Cell viability and apoptosis were detected using MTT and flow cytometry assays, respectively. ELISA was used for determination of inflammatory cytokines and western blotting for evaluation of protein expression. Pretreatment of HFLS-RA cells with 0.5, 1.0, 1.5, 2.0, and 2.5 μM doses of OMTH suppressed TNF-α induced promotion of proliferative potential in dose-based manner. The OMTH pretreatment of TNF-α exposed HFLS-RA cells significantly increased apoptotic cell proportion. In TNF-α exposed HFLS-RA cells OMTH pretreatment elevated Bax and suppressed Bcl-2 expression. Treatment of HFLS-RA cells with OMTH prevented TNF-α mediated elevation of IL-1β, IL-6 and IL-8. Moreover, OMTH treatment of HFLS-RA cells effectively suppressed TNF-α mediated elevated levels of MMP-1 and MMP-13. Pretreatment of HFLS-RA cells with OMTH reversed TNF-α mediated promotion of iNOS and COX-2 levels. The MEK/1/2 and p65 phosphorylation in TNF-α exposed HFLS-RA cells was reduced by OMTH pre-treatment in dose-based manner. Thus, OMTH successfully inhibited TNF-α-mediated increased viability of RA synovial cells and activated apoptosis. Pretreatment of TNF-α exposed synovial cells with OMTH targeted phosphorylation of MEK/NF-κB. Therefore, OMTH may act as potential therapeutic agent for RA treatment.

Identifying new compounds with potential pharmaceutical and physiological activity in Areca catechu and Areca triandra via a non-targeted metabolomic approach

INTRODUCTION

The fruits of Areca catechu, also called areca nuts, are widely used as popular masticatory and traditional herbal medicine in Asia. Besides arecoline and related alkaloids, limited information is available about further primary and secondary metabolites and their potential biological activities.

OBJECTIVE

Here we aimed to further enhance our knowledge on phytochemical profiles of A. catechu and Areca triandra fruits. We intended to comprehensively identify metabolites in A. catechu and A. triandra fruits.

METHODOLOGY

Metabolites were identified by ultra-performance liquid chromatography triple-quadrupole tandem mass spectrometry (UPLC-MS/MS). The occurrence of 12 selected bioactive compounds in 4 different developmental stages of A. catechu and A. triandra was quantified by LC-MS/MS.

RESULTS

A total of 791 metabolites was identified. Of these, 115 metabolites could successfully be mapped to 44 Kyoto Encyclopedia of Genes and Genomes metabolic pathways, and 154 metabolites occurred at significantly different levels in A. catechu compared to A. triandra. Several components with known biological activities were identified for the first time in A. catechu and A. triandra. The abundance of many of these new components was similar in A. catechu and A. triandra, but significantly different between the pericarp and the seeds of A. catechu fruits.

CONCLUSIONS

Metabolic profiles indicate that fruits of the Areca species compared here have similar primary and secondary metabolites. Our findings provide new insights into A. catechu and A. triandra as valuable sources for traditional medicine and they pave the way for further studies to potentially improve the underlying pharmaceutical and physiological effects.

Avicularin suppresses cartilage extracellular matrix degradation and inflammation via TRAF6/MAPK activation

BACKGROUND

Osteoarthritis (OA) is an intractable degenerative disease of the whole joint, which is characterized by synovitis inflammation, cartilage damage, and chronic pain. Tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) performs an important role in OA.

PURPOSE

We aim to investigate avicularin to protect cartilage extracellular matrix degradation (ECM) and suppresses inflammation both in rat and human chondrocytes.

METHODS

5-Ethynyl-2'-deoxyuridine (EdU) staining, Quantitative real-time PCR, TRAF6 plasmid transfection, Western blot, Measurement of nitric oxide (NO), ROS detection and Immunofluorescence were utilized in vitro. micro-CT scanning, Safranin O-Fast Green, toluidine blue and immunohistochemistry staining were performed in vivo.

RESULTS

In vitro, avicularin attenuates the degradation of ECM and inflammation, which could inhibit the activation of TRAF6/MAPK pathway via targeting TRAF6. Increased MMP3 and MMP13 expressions and decreased Aggrecan and Collagen Ⅱ levels were observed in anterior cruciate ligament transection (ACLT) induced osteoarthritic rats. Interestingly, intra-articular injection of avicularin attenuates this phenomenon.

CONCLUSIONS

Taken together, our results indicate that avicularin suppresses cartilage extracellular matrix degradation and inflammation via TRAF6/MAPK activation by targeting TRAF6. These observations identify TRAF6 as a relevant drug target, and avicularin may as a potential therapeutic agent in osteoarthritis.

LC-HRMS Profiling and Antidiabetic, Antioxidant, and Antibacterial Activities of Acacia catechu (L.f.) Willd

Acacia catechu (L.f.) Willd is a profoundly used traditional medicinal plant in Asia. Previous studies conducted in this plant are more confined to extract level. Even though bioassay-based studies indicated the true therapeutic potential of this plant, compound annotation was not performed extensively. This research is aimed at assessing the bioactivity of different solvent extracts of the plant followed by annotation of its phytoconstituents. Liquid chromatography equipped with high resolution mass spectrometry (LC-HRMS) is deployed for the identification of secondary metabolites in various crude extracts. On activity level, its ethanolic extract showed the highest inhibition towards α-amylase and α-glucosidase with an IC₅₀ of 67.8 ± 1 μg/mL and 10.3 ± 0.1 μg/mL respectively, inspected through the substrate-based method. On the other hand, the plant extract showed an antioxidant activity of 23.76 ± 1.57 μg/mL, measured through radical scavenging activity. Similarly, ethyl acetate and aqueous extracts of A. catechu showed significant inhibition against Staphylococcus aureus with a zone of inhibition (ZoI) of 13 and 14 mm, respectively. With the LC-HRMS-based dereplication strategy, we have identified 28 secondary metabolites belonging to flavonoid and phenolic categories. Identification of these metabolites from A. catechu and its biological implication also support the community-based usage of this plant and its medicinal value.

Stevia Genus: Phytochemistry and Biological Activities Update

The Stevia genus (Asteraceae) comprises around 230 species, distributed from the southern United States to the South American Andean region. Stevia rebaudiana, a Paraguayan herb that produces an intensely sweet diterpene glycoside called stevioside, is the most relevant member of this genus. Apart from S. rebaudiana, many other species belonging to the Stevia genus are considered medicinal and have been popularly used to treat different ailments. The members from this genus produce sesquiterpene lactones, diterpenes, longipinanes, and flavonoids as the main types of phytochemicals. Many pharmacological activities have been described for Stevia extracts and isolated compounds, antioxidant, antiparasitic, antiviral, anti-inflammatory, and antiproliferative activities being the most frequently mentioned. This review aims to present an update of the Stevia genus covering ethnobotanical aspects and traditional uses, phytochemistry, and biological activities of the extracts and isolated compounds.

Bilberry (Vaccinium myrtillus L.) Extracts Comparative Analysis Regarding Their Phytonutrient Profiles, Antioxidant Capacity along with the In Vivo Rescue Effects Tested on a Drosophila melanogaster High-Sugar Diet Model

Bilberries (Vaccinium myrtillus L.) have been reported to hold a plentitude of health-promoting properties beyond basic nutrition, mainly attributed to their anthocyanin content and antioxidant activity. In this article, we built the phytochemical profile of three wild bilberry fruit extract formulations (aqueous, methanolic, and hydro-methanolic) using UHPLC-ESI-MS/MS putative analysis, identifying 88 individual phytochemicals, mainly flavonoids (total content 8.41 ± 0.11 mg QE/g dw), free amino acids, polyphenols (total content 21.68 ± 0.19 mg GAE/g dw), carboxylic acids, and vitamins. Furthermore, the antioxidant activity of the extract was assessed, reaching 78.03 ± 0.16% DPPH free radical scavenging activity, comparable to literature values determined for bilberry extracts of other origin. Due to the increased prevalence of metabolic syndrome and based on the reviewed benefits of bilberries, we tested the most potent formulation of our bilberry extracts in this biological context. The in vivo rescue effect of a bilberry extract supplemented diet on Drosophila melanogaster was assessed by monitoring biochemical and genomic markers. Hemolymph trehalose levels were halved upon addition of 3% hydro-methanolic bilberry extract to a high-sugar (1.5 M sucrose) diet, as compared to the non-supplemented high-sugar diet. Noteworthy, the rescue seen for flies kept on the bilberry extract supplemented high-sugar diet appeared to parallel the trehalose levels observed in the case of the control diet (50 mM sucrose) flies. Moreover, next to the trehalose-lowering type of in vivo effects, other gene expression related rescues were also detected for genes such as InR, Akh, AstA, AstC, Irk, Npc2g, and CCHa2 upon supplementation of the high-sugar diet with our hydro-methanolic bilberry fruit extract. Our findings suggest that such a bilberry fruit extract could generate physiological and genomic type of compensatory mechanisms so that further translational approaches would advance the understanding of some human specific pathological conditions.

Retinoic Acid-Platinum (II) Complex [RT-Pt(II)] Protects Against Rheumatoid Arthritis in Mice via MEK/Nuclear Factor kappa B (NF-κB) Pathway Downregulation

Background

Rheumatoid arthritis (RA) is an inflammatory disorder that is present in approximately 1% of the world’s population. This study was aimed to investigate the effect of retinoic acid-platinum (II) complex [RT-Pt(II)] on rheumatoid arthritis (RA) and to explore the mechanism involved.

Material/Methods

MH7A cell viability was determined by MTT assay and apoptosis was assessed using FACSCalibur flow cytometry. RT-PCR and Western blot assays were used for assessment of mRNA and proteins levels.

Results

Treatment of rheumatoid arthritis with RT-Pt(II) significantly reduced the levels of IL-1β, IL-6, IL-8, MMP-1, and MMP-13 in synovial fluid of mice in a dose-dependent manner. The expression of iNOS and COX-2 mRNA and protein in rheumatoid arthritis rats was also significantly inhibited by treatment with RT-Pt(II). The TNF-α-induced proliferation of MH7A cells was alleviated by RT-Pt(II) treatment in a concentration-dependent manner. Moreover, RT-Pt(II) treatment induced apoptosis and caused arrest of cell cycle in MH7A cells. The activation of MEK/NF-κB pathway was downregulated by RT-Pt(II) treatment in MH7A cells.

Conclusions

In summary, the present study demonstrated that RT-Pt(II) inhibits TNF-α-induced inflammatory response, suppresses cell viability, and induces apoptosis in rheumatoid arthritis synovial cells. Moreover, RT-Pt(II) exhibited its effect through targeting the MEK/NF-κB pathway. Therefore, RT-Pt(II) can be used for the development of treatments for rheumatoid arthritis.

Acyclic Triterpenoid Isolated from Alpinia katsumadai Alleviates Formalin-Induced Chronic Mouse Paw Inflammation by Inhibiting the Phosphorylation of ERK and NF-κB

Chronic and excessive inflammation can destroy host organs and cause inflammatory diseases such as inflammatory bowel disease, asthma, and rheumatoid arthritis. In this study, we investigated the anti-inflammatory effects of Alpinia katsumadai seed-derived 2,3,5,22,23-pentahydroxy-2,6,10,15,19,23-hexamethyl-tetracosa-6,10,14,18-tetraene (PHT) using lipopolysaccharide (LPS)-stimulated J774 cells and a formalin-induced chronic paw inflammation mouse model. The in vitro results showed that PHT exhibited no cytotoxicity and decreased LPS-induced NO secretion. Additionally, PHT inhibited LPS-induced inducible NO synthase (iNOS) and cyclooxygenase 2 (COX2) protein expression. The quantitative real-time PCR results showed that PHT downregulated the gene expression of the proinflammatory cytokines interleukin-1β (IL-1β) and interleukin-6 (IL-6) but not tumor necrosis factor α (TNF-α). PHT inhibited the LPS-induced phosphorylation of extracellular signal-regulated kinase (ERK) and nuclear factor kappa light chain enhancer of activated B cells (NF-κB). In a mouse model, oral administration of 50 mg/kg PHT significantly alleviated both mouse paw thickness and volume. These results indicate that PHT has potential anti-inflammatory effects and should be considered a possible functional material.

Screening and druggability analysis of some plant metabolites against SARS-CoV-2: An integrative computational approach

The sudden outbreak of novel coronavirus has caused a global concern due to its infection rate and mortality. Despite extensive research, there are still no specific drugs or vaccines to combat SARS-CoV-2 infection. Hence, this study was designed to evaluate some plant-based active compounds for drug candidacy against SARS-CoV-2 by using virtual screening methods and various computational analyses. A total of 27 plant metabolites were screened against SARS-CoV-2 main protease proteins (MPP), Nsp9 RNA binding protein, spike receptor binding domain, spike ecto-domain and HR2 domain using a molecular docking approach. Four metabolites, i.e., asiatic acid, avicularin, guajaverin, and withaferin showed maximum binding affinity with all key proteins in terms of lowest global binding energy. The crucial binding sites and drug surface hotspots were unravelled for each viral protein. The top candidates were further employed for ADME (absorption, distribution, metabolism, and excretion) analysis to investigate their drug profiles. Results suggest that none of the compounds render any undesirable consequences that could reduce their drug likeness properties. The analysis of toxicity pattern revealed no significant tumorigenic, mutagenic, irritating, or reproductive effects by the compounds. However, withaferin was comparatively toxic among the top four candidates with considerable cytotoxicity and immunotoxicity. Most of the target class by top drug candidates belonged to enzyme groups (e.g. oxidoreductases hydrolases, phosphatases). Moreover, results of drug similarity prediction revealed two approved structural analogs of Asiatic acid i.e. Hydrocortisone (DB00741) (previously used for SARS-CoV-1 and MERS) and Dinoprost-tromethamine (DB01160) from DrugBank. In addition, two other biologically active compounds, Mupirocin (DB00410) and Simvastatin (DB00641) could be an option for the treatment of viral infections. The study may pave the way to develop effective medications and preventive measure against SARS-CoV-2. Due to the encouraging results, we highly recommend further in vivo trials for the experimental validation of our findings.

Avicularin Reduces the Expression of Mediators of Inflammation and Oxidative Stress in Bradykinin-Treated MG-63 Human Osteoblastic Osteosarcoma Cells

BACKGROUND Avicularin is a plant-derived flavonoid used in traditional Chinese medicine to treat conditions that include ankle fracture. Bradykinin stimulated MG-63 human osteoblastic osteosarcoma cells has previously been studied in an in vitro model. This study aimed to investigate the effects of avicularin on bradykinin-treated MG-63 human osteoblastic osteosarcoma cells in vitro. MATERIAL AND METHODS MG-63 cells were treated with increasing concentrations of avicularin for 48 hours, followed by 1 μM of bradykinin for 24 h. The MTT assay was used to measure cell viability. Quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) were used to measure the expression of inflammatory mediators, interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-alpha (TNF-alpha) mRNA and protein, respectively. The expression of oxidative stress factors, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase were measured. Western blot and qRT-PCR were performed to determine p38, p65, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) protein levels and mRNA expression, respectively. RESULTS Avicularin had no cytotoxic effect on MG-63 cells. Avicularin significantly upregulated the expression levels IL-1ß, IL-6, and TNF-alpha in the bradykinin treated group in a dose-dependent manner. Avicularin reduced the level of MDA and the activity of SOD and catalase in the bradykinin treated MG-63 cells, reduced p-p38, p-p65, iNOS, and COX-2 expression, and decreased the p-p38/p38 ratio and the p-p65/p65 ratio in bradykinin treated MG-63 cells in a dose-dependent manner. CONCLUSIONS Avicularin reduced the expression of inflammatory cytokines and the levels of markers of oxidative stress in MG-63 human osteoblastic osteosarcoma cells in vitro.

Elsholtzia ciliata (Thunb.) Hyl. Extracts from Different Plant Parts: Phenolic Composition, Antioxidant, and Anti-Inflammatory Activities

Polyphenols play an important role on the health-promoting properties of humans. Plants belonging to Lamiaceae family are known as rich source of phenolic compounds. The current work aimed to evaluate the phenolic compounds, antioxidant, and anti-inflammatory activity of Elsholtzia ciliata (Thunb.) Hyl. ethanolic extracts from leaf, stem, flower, and whole herb. Twelve compounds were identified in ethanolic extracts using high-performance liquid chromatography (HPLC). The HPLC analysis revealed that chlorogenic acid, rosmarinic acid, and rutin were predominant compounds in ethanolicic extracts. Using HPLC-ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) post-column assay, avicularin, chlorogenic, and rosmarinic acids were identified as the predominant radical scavengers in all ethanolic extracts. All tested preparations significantly reduced the level of secretion of proinflammatory cytokines TNF-α, IL-6, and prostaglandin E2 induced by lipopolysaccharide treatment in mouse peritoneal macrophage cell culture. Stem and flower extracts were most efficient in reducing cytokine release, but leaf extract demonstrated stronger effect on prostaglandin E2 secretion. This is the first study exploring antioxidant efficiency by HPLC–ABTS post-column method and investigating anti-inflammatory activity of ethanolic extracts from E. ciliata different plant parts.

Avicularin inhibits cell proliferation and induces cell apoptosis in cutaneous squamous cell carcinoma

Avicularin (AL), quercetin-3-α-L-arabinofuranoside, has various pharmacological properties such as anticancer and anti-infective effects. However, the potential molecular mechanism via which AL exerts its anticancer activity is not fully understood. Cutaneous squamous cell carcinoma (CSCC) is the second most common skin cancer, where metastasis has resulted in in effective clinical treatments. The aim of the present in vitro study was to investigate the anticancer effects and underlying mechanism of AL on human CSCC. The present results suggested that AL dose-dependently inhibited SCC13 cell viability and induced apoptosis. In addition, the present results suggested that AL induced apoptosis via repression of the mitogen-activated protein kinase kinase (MEK)/NF-κB signal pathway, thereby affecting the expression of apoptosis-related genes. Bax expression level was increased, while Bcl-2 expression level was decreased in SCC13 cells following AL treatment. In addition, the MEK/NF-κB signaling pathway-related genes p-MEK and phosphorylated-p65 were also decreased. The present results suggested that AL treatment increased the expression level of E-cadherin, but decreased the expression levels of N-cadherin, matrix metalloproteinase (MMP)-9 and vimentin in SCC13 cells. Collectively, the present results suggested that AL may have an anti-CSCC effect by inhibiting cell viability, inducing apoptosis and inhibiting epithelial-mesenchymal transition (EMT) of CSCC cells. The mechanism of these anti-CSCC effects was suggested to be via the regulation of apoptosis-related genes and EMT-related genes, and the inhibition of the MEK/NF-κB signaling pathway.

Hepatic transcriptome and proteome analyses provide new insights into the regulator mechanism of dietary avicularin in diabetic mice

Many dietary flavonoids existing as glycosides in fruits and vegetables are considered bioactive food components with various potential health benefits. Type 2 diabetes mellitus (T2DM) is a complex and polygenic disease with increasing global prevalence and economic burden. In this study, the hypoglycemic effect of avicularin (quercetin-3-O-α-arabinofuranoside), a flavonoid glycoside commonly found in natural plants and fruits, was determined in a high fat diet/streptozotocin induced type 2 diabetes mouse model. Our results demonstrated that dietary avicularin treatment reduced levels of fasting blood glucose, serum TG and LDL-C, liver AST and ALT, and increased hepatic glycogen in T2DM mice. Furthermore, we used RNA-Seq and iTRAQ to compare the gene and protein expression in the livers of the normal control mice (NC), diabetic control mice (DC) and avicularin treated mice (DA100). The differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) were analyzed based on gene annotations and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. Integrated analysis of the RNA-Seq and iTRAQ data indicated that the fifteen DEGs/DEPs showed the same trend in mRNA and protein expression levels in comparisons of both NC vs DC and DC vs DA100. KEGG analysis revealed that four DEGs/DEPs (PKM, PEPCK, PYG, and PLA2) in the glycolysis, gluconeogenesis, and arachidonic acid pathway, and six DEPs (Ndufb4, Ndufa6, Cox5a, Cox5b, Cox6c, and ATPSβ) in the oxidative phosphorylation signaling pathway, play important roles in avicularin's hypoglycemic effect. We also found six other DEGs/DEPs related to T2DM (CA1, Serpinb6a, AK, Pcolce, Cand2, and Atp2a3), and five related to cancer (Phgdh, Tes, Papss1, Psat1, and Fam49b). We did further verify by qRT-PCR and explored the possible binding modes of avicularin with targeted proteins with molecular docking simulations. Taken together, our results demonstrated the protective effects of avicularin against diabetes and provided a global view about the system-level hypoglycemic mechanisms of avicularin by the comprehensive analysis of transcriptomic and proteomic data in T2DM mice.

Avicularin ameliorates human hepatocellular carcinoma via the regulation of NF‑κB/COX‑2/PPAR‑γ activities

Hepatocellular carcinoma (HCC) has become a global public health problem. Therefore, the development of novel and effective therapeutic agents for the treatment of HCC is considered an emergency. Avicularin, a bio-active flavonoid from plants, has been reported to exhibit diverse pharmacological properties. The aim of the present study was to investigate the role of avicularin in HCC and the underlying mechanism of action. Huh7 cells were treated with avicularin in a concentration-dependent manner, and the cell proliferation was examined using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay kit. The cell migration and invasion abilities were detected using wounding-healing assays and Transwell assays. Flow cytometric analysis was performed to investigate the cell cycle distribution and cell apoptosis. The activity of nuclear factor (NF)-κB (p65), cyclooxygenase-2 (COX-2) and peroxisome proliferator-activated receptor γ (PPAR-γ) were measured by reverse transcription-quantitative polymerase chain reaction and western blot analyses, respectively. The results indicated that avicularin treatment markedly decreased cell proliferation concentration-dependently in HCC, and inhibited cell migration and invasion in Huh7 cells. It was also found that the treatment of avicularin markedly inhibited the G0/G1-phase cells and decreased the accumulation of S-phase cells in the cell cycle and induced cell apoptosis. In addition, it was confirmed that the anticancer efficacy of avicularin in HCC was dependent on the regulation of NF-κB (p65), COX-2 and PPAR-γ activities. In conclusion, the findings suggested that avicularin serves an antineoplastic role in HCC and may provide a potential therapeutic strategy for the treatment of HCC.

Avicularin Relieves Depressive-Like Behaviors Induced by Chronic Unpredictable Mild Stress in Mice

Background

Avicularin (AL, quercetin-3-α-l-arabinofuranoside), a glycoside of quercetin, has been reported to display diverse pharmacological properties. The present study aimed to investigate whether AL has an anti-depressant-like effect on a mouse model of depression induced by chronic unpredictable mild stress (CUMS).

Material/Methods

A mouse model of depression was established and treated with different concentrations of AL (1.25, 2.5 or 5.0 mg/kg/d) and fluoxetine (20 mg/kg/d). Then, behavioral tests – sucrose preference test (SPT), forced swimming test (FST), and the tail suspension test (TST) – were performed. The levels proinflammatory cytokines – interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) – in the hippocampi of mice were detected by enzyme-linked immunosorbent assay (ELISA). Apoptosis of hippocampal neuronal cells was determined using flow cytometry. Expression levels of phosphorylated (p)-MEK1/2, p-ERK1/2, p-NF-κB (p-p65), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), Caspase3, and B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax) were measured by Western blot assay or/and quantitative real-time polymerase chain reaction (qRT-PCR), respectively.

Results

The results showed that AL significantly relieved CUMSinduced depressive-like behaviors. Compared with the model mice, AL treatment significantly increased the sucrose preference of the mice, and the immobility time in the FST and the TST were shortened. We also found that AL decreased CUMS-induced increases in the levels of IL-1β, IL-6, and TNF-α in the hippocampi of mice. AL significantly decreased the apoptosis rate of hippocampal neuronal cells in mice, which was increased by CUMS. Furthermore, activation of the MEK/ERK/NF-κB pathway induced by CUMS was inhibited by AL treatment.

Conclusions

Our results show the anti-depressant-like effects of AL on CUMS-induced depression in a mouse model.

Network Pharmacology and Reverse Molecular Docking-Based Prediction of the Molecular Targets and Pathways for Avicularin Against Cancer

AIM AND OBJECTIVE

Avicularin has been found to inhibit the proliferation of HepG-2 cells in vitro in the screening of our laboratory. We intended to explain the molecular mechanism of this effect. Therefore, the combined methods of reverse molecular docking and network pharmacology were used in order to illuminate the molecular mechanisms for Avicularin against cancer.

MATERIALS AND METHODS

Potential targets associated with anti-tumor effects of Avicularin were screened by reverse molecular docking, then a protein database was established through constructing the drugprotein network from literature mining data, and the protein-protein network was built through an in-depth exploration of the relationships between the proteins, and then the network topology analysis was performed. Additionally, gene function and signaling pathways were analyzed by Go bio-enrichment and KEGG Pathway.

RESULTS

The result showed that Avicularin was closely related to 16 targets associated with cancer, and it may significantly influence the pro-survival signals in MAPK signaling pathway that can activate and regulate a series of cellular activities and participate in the regulation of cell proliferation, differentiation, transformation and apoptosis.

CONCLUSION

The network pharmacology strategy used herein provided a powerful means for the mechanisms of action for bioactive ingredients.

Phytochemicals and inflammatory bowel disease: a review

Gastrointestinal tract is the second largest organ in the body that mainly functions in nutrients and minerals intake through the intestinal barrier. Intestinal permeability maintains the circulation of minerals and nutrients from digested foods. Life and all the metabolic processes depend either directly or indirectly on proper functioning of GI tract. Compromised intestinal permeability and related disorders are common among all the patients with inflammatory bowel disease (IBD), which is a collective term of inflammatory diseases including Crohn's disease and ulcerative colitis. Many synthetic drugs are currently in use to treat IBD such as 5-aminosalicylic acid corticosteroids. However, they all have some drawbacks as long-term use result in many complications. These problems encourage us to look out for alternative medicine. Numerous in vitro and in vivo experiments showed that the plant-derived secondary metabolites including phenolic compounds, glucosinolates, alkaloids, terpenoids, oligosaccharides, and quinones could reduce permeability, ameliorate-related dysfunctions with promising results. In addition, many of them could modulate enzymatic activity, suppress the inflammatory transcriptional factors, ease oxidative stress, and reduce pro-inflammatory cytokines secretion. In this review, we summarized the phytochemicals, which were proven potent in treating increased intestinal permeability and related complication along with their mechanism of action.

Screening of ordinary commercial varieties of apple fruits under different storage conditions for their potential vascular and metabolic protective properties

Epidemiological studies reported that apple consumption is associated with a decrease of cardiovascular and metabolic dysfunction, probably due to the polyphenols and fibers present in this fruit. The storage conditions and genetic origin of apples have been reported to influence their content and, as a consequence, their pharmacological properties. The present study evaluated the influence of varieties and storage conditions of traditional and highly appreciated apples including Gala, Golden Delicious, Granny Smith and Pink Lady varieties after harvest and storage under classic cold conditions, under a controlled atmosphere, or under extreme ultra-low oxygen conditions. Thus, a multi-parametric screening on cell models associated with vascular and metabolic dysfunctions - such as endothelial and smooth muscle cells, hepatocytes, adipocytes and macrophages - in relation to the apple polyphenol content has been developed. This strategy demonstrated that, overall, peeled apple samples exhibited a vascular tropism and acted mainly on proliferation and oxidative stress in endothelial and smooth muscle cells. Apple extracts appeared to be less effective on adipocytes and macrophages, but they exhibited antioxidant properties in hepatocytes. Among the varieties, Gala and Golden Delicious were the most efficient against the processes involved in the development of atherosclerosis. Concerning storage conditions, most of the apple varieties were more efficient under harvest conditions, while they could not be discriminated under all other cold conditions and the concentration used, except for the Gala samples. Interestingly, pharmacological properties were associated with the polyphenol profiles of freeze dried apple flesh powder. The present report revealed the potential use of some apple extracts as effective food supplements or nutraceuticals for the prevention and/or management of cardiovascular and metabolic diseases.

Protective effect of avicularin on rheumatoid arthritis and its associated mechanisms

The present study aimed to investigate the effect of avicularin on rheumatoid arthritis (RA) in vitro, and additionally explore the molecular mechanism. To perform this investigation, an in vitro model of RA was established by treatment of the human RA synovial MH7A cell line with tumor necrosis factor-α (TNF-α). MH7A cells were then treated with various concentrations (10, 30, 100 and 300 µM) of avicularin. Then, the levels of inflammatory factors [interleukin (IL)-1β, IL-6, IL-8, matrix metalloproteinase (MMP)-1 and MMP-13] were measured by ELISA. Cell viability and apoptosis were detected using an MTT assay and flow cytometry, respectively. In addition, the expression levels of genes and proteins were determined reverse transcription quantitative polymerase chain reaction and western blot analysis. The results of the present study indicated that avicularin significantly decreased the levels of inflammatory factors (IL-1β, IL-6, IL-8, MMP-1 and MMP-13), previously increased by TNF-α, in a dose-dependent manner. Concurrently, avicularin inhibited the mRNA and protein expression levels of iNOS and COX-2 increased by TNF-α. It was also identified that TNF-α administration significantly promoted MH7A cell viability and inhibited cell apoptosis, and avicularin treatment dose-dependently inhibited MH7A cell viability and induced cell apoptosis. In addition, these data suggested that avicularin prevented the activation of the mitogen-activated protein kinase kinase (MEK)/nuclear factor kappa light-chain-enhancer of activated B-cells (NF-κB) pathway activated by TNF-α. Taken together, these results demonstrated that avicularin may inhibit the inflammatory response, prevent cell viability and induce apoptosis in human RA synovial cells through preventing the activation of the MEK/NF-κB pathway.

MerTK signaling in macrophages promotes the synthesis of inflammation resolution mediators by suppressing CaMKII activity

Inflammation resolution counterbalances excessive inflammation and restores tissue homeostasis after injury. Failure of resolution contributes to the pathology of numerous chronic inflammatory diseases. Resolution is mediated by endogenous specialized proresolving mediators (SPMs), which are derived from long-chain fatty acids by lipoxygenase (LOX) enzymes. 5-LOX plays a critical role in the biosynthesis of two classes of SPMs: lipoxins and resolvins. Cytoplasmic localization of the nonphosphorylated form of 5-LOX is essential for SPM biosynthesis, whereas nuclear localization of phosphorylated 5-LOX promotes proinflammatory leukotriene production. We previously showed that MerTK, an efferocytosis receptor on macrophages, promotes SPM biosynthesis by increasing the abundance of nonphosphorylated, cytoplasmic 5-LOX. We now show that activation of MerTK in human macrophages led to ERK-mediated expression of the gene encoding sarcoplasmic/endoplasmic reticulum calcium ATPase 2 (SERCA2), which decreased the cytosolic Ca2+ concentration and suppressed the activity of calcium/calmodulin-dependent protein kinase II (CaMKII). This, in turn, reduced the activities of the mitogen-activated protein kinase (MAPK) p38 and the kinase MK2, resulting in the increased abundance of the nonphosphorylated, cytoplasmic form of 5-LOX and enhanced SPM biosynthesis. In a zymosan-induced peritonitis model, an inflammatory setting in which macrophage MerTK activation promotes resolution, inhibition of ERK activation delayed resolution, which was characterized by an increased number of neutrophils and decreased amounts of SPMs in tissue exudates. These findings contribute to our understanding of how MerTK signaling induces 5-LOX-derived SPM biosynthesis and suggest a therapeutic strategy to boost inflammation resolution in settings where defective resolution promotes disease progression.

Avicularin reversed multidrug-resistance in human gastric cancer through enhancing Bax and BOK expressions

5-Fluorouracil (5-Fu) and cisplatin (DDP) as important therapies in treatment of human gastric cancer have been widely determined. However, the therapeutic effects are usually hampered due to drug resistance or toxicity at high concentrations for application. Avicularin (AL, quercetin-3-α-l-arabinofuranoside), a bio-active flavonol isolated from a number of plants, has been reported to display diverse pharmacological properties. In this study, we explored the hypothesis by which AL reversed 5-Fu or DDP resistance in gastric cancer and the underlying molecular mechanism. Here, in vitro, the drug-resistant cancer cells were incubated to AL or DDP alone or the combination of AL and DDP. Then, MTT, colony formation, Hoechst 33258, flow cytometry and western blot analysis were used to investigate the effects of AL in the regulation of drug-resistance gastric cancer cells. The results indicated that AL treatment markedly re-sensitizes the drug resistant cells (SGC-7901/5-Fu and SGC-7901/DDP) to cytotoxicity of 5-Fu or DDP. Molecular mechanism analysis indicated that AL and DDP combination treatment enhanced apoptosis in SGC-7901/DDP cells, accompanied with the up-regulation of cleaved Caspase-3 and PARP, as well as the activation of pro-apoptotic signals, including Bax and BOK. Significantly, down regulation of Bax or BOK expressions using Bax siRNA or BOK siRNA decreased the inhibitory role of DDP in apoptosis of SGC-7901/DDP cells pretreated with AL, demonstrating that AL-reversed DDP resistance was associated with Bax and BOK expression. In vivo, AL and DDP combination significantly reduced gastric tumor growth. Immunohistochemical analysis indicated that co-treatment of AL and DDP significantly induced apoptosis, and reduced tumor cell proliferation in tumor tissue samples. Furthermore, we also found that the Bax, BOK, cleaved Caspase-3 and PARP expression in tumor tissues were highly induced by AL and DDP co-treatment. Together, our findings may provide a novel combination therapeutic strategy in treatment of human gastric cancer.

Phytochemical Composition and Biological Activities of Dyssodia tagetiflora Lag

While plants of the genus Dyssodia are used by man to a certain extent, few phytochemical and pharmacological studies have been performed with species of this genus. D. tagetiflora is an endemic plant of Mexico and has been used as fodder. The aim of this research was to isolate and identify the main bioactive components and evaluate the insecticidal, antioxidant, genotoxic and cytoprotective activities of D. tagetiflora. The isolated substances included an essential oil composed of six monoterpenes, and extracts containing two flavonols, three flavonol-glycosides and four thiophenes. The compounds were characterized using spectroscopic and spectrometric methods, including GC/MS, MS and NMR. The essential oil showed insecticidal activity against Drosophila melanogaster larvae. The methanolic extract of D. tagetiflora (DTME) had strong antioxidant activity against DPPH and ABTS radicals; DTME showed no evidence of genotoxic or cytotoxic effects. In contrast, DTME showed a cytoprotective effect attenuating the formation of H₂ O₂ -induced micronuclei in Vicia faba roots. This report is the first to describe the phytochemical and biological activity of D. tagetiflora.

Hydroquinone suppresses IFN-β expression by targeting AKT/IRF3 pathway

Previous studies have demonstrated the role of hydroquinone (HQ), a hydroxylated benzene metabolite, in modulating various immune responses; however, its role in macrophage-mediated inflammatory responses is not fully understood. In this study, the role of HQ in inflammatory responses and the underlying molecular mechanism were explored in macrophages. HQ down-regulated the expression of interferon (IFN)-β mRNA in LPS-stimulated RAW264.7 cells without any cytotoxicity and suppressed interferon regulatory factor (IRF)-3-mediated luciferase activity induced by TIR-domain-containing adapter-inducing interferon-β (TRIF) and TANK-binding kinase 1 (TBK1). A mechanism study revealed that HQ inhibited IRF-3 phosphorylation induced by lipopolysaccharide (LPS), TRIF, and AKT by suppressing phosphorylation of AKT, an upstream kinase of the IRF-3 signaling pathway. IRF-3 phosphorylation is highly induced by wild-type AKT and poorly induced by an AKT mutant, AKT C310A, which is mutated at an inhibitory target site of HQ. We also showed that HQ inhibited IRF-3 phosphorylation by targeting all three AKT isoforms (AKT1, AKT2, and AKT3) in RAW264.7 cells and suppressed IRF-3-mediated luciferase activities induced by AKT in HEK293 cells. Taken together, these results strongly suggest that HQ inhibits the production of a type I IFN, IFN-β, by targeting AKTs in the IRF-3 signaling pathway during macrophage-mediated inflammation.

Quercetin-3-O-β-D-Glucuronide Suppresses Lipopolysaccharide-Induced JNK and ERK Phosphorylation in LPS-Challenged RAW264.7 Cells

Quercetin, a flavonol, has been reported to exhibit a wide range of biological properties including anti-oxidant and anti-inflammatory activities. However, pharmacological properties of quercetin-3-O-β-D-glucuronide (QG), a glycoside derivative of quercetin, have not been extensively examined. The objective of this study is to elucidate the anti-inflammatory property and underlying mechanism of QG in lipopolysaccharide (LPS)-challenged RAW264.7 macrophage cells in comparison with quercetin. QG significantly suppressed LPS-induced extracellular secretion of pro-inflammatory mediators such as nitric oxide (NO) and PGE₂, and pro-inflammatory protein expressions of iNOS and COX-2. To elucidate the underlying mechanism of the anti-inflammatory property of QG, involvement of MAPK signaling pathways was examined. QG significantly attenuated LPS-induced activation of JNK and ERK in concentration-dependent manners with a negligible effect on p38. In conclusion, the present study demonstrates QG exerts anti-inflammatory activity through the suppression of JNK and ERK signaling pathways in LPS-challenged RAW264.7 macrophage cells.

Flavonoid glycosides from Persea caerulea. Unraveling their interactions with SDS-micelles through matrix-assisted DOSY, PGSE, mass spectrometry, and NOESY

Two flavonoid glycosides derived from rhamnopyranoside (1) and arabinofuranoside (2) have been isolated from leaves of Persea caerulea for the first time. The structures of 1 and 2 have been established by ¹ H NMR, ¹³ C NMR, and IR spectroscopy, together with LC-ESI-TOF and LC-ESI-IT MS spectrometry. From the MS and MS/MS data, the molecular weights of the intact molecules as well as those of quercetin and kaempferol together with their sugar moieties were deduced. The NMR data provided information on the identity of the compounds, as well as the α and β configurations and the position of the glycosides on quercetin and kaempferol. We have also explored the application of sodium dodecyl sulfate (SDS) normal micelles in binary aqueous solution, at a range of concentrations, to the diffusion resolution of these two glycosides, by the application of matrix-assisted diffusion ordered spectroscopy (DOSY) and pulse field gradient spin echo (PGSE) methodologies, showing that SDS micelles offer a significant resolution which can, in part, be rationalized in terms of differing degrees of hydrophobicity, amphiphilicity, and steric effects. In addition, intra-residue and inter-residue proton-proton distances using nuclear Overhauser effect build-up curves were used to elucidate the conformational preferences of these two flavonoid glycosides when interacting with the micelles. By the combination of both diffusion and nuclear Overhauser spectroscopy techniques, the average location site of kaempferol and quercetin glycosides has been postulated, with the former exhibiting a clear insertion into the interior of the SDS-micelle, whereas the latter is placed closer to the surface. Copyright © 2016 John Wiley & Sons, Ltd.

Topical anti-inflammatory effects of isorhamnetin glycosides isolated from Opuntia ficus-indica

Opuntia ficus-indica (OFI) has been widely used in Mexico as a food and for the treatment of different health disorders such as inflammation and skin aging. Its biological properties have been attributed to different phytochemicals such as the isorhamnetin glycosides which are the most abundant flavonoids. Moreover, these compounds are considered a chemotaxonomic characteristic of OFI species. The aim of this study was to evaluate the effect of OFI extract and its isorhamnetin glycosides on different inflammatory markers in vitro and in vivo. OFI extract was obtained by alkaline hydrolysis of OFI cladodes powder and pure compounds were obtained by preparative chromatography. Nitric oxide (NO), cyclooxygenase-2 (COX-2), tumor necrosis factor- (TNF-) α, and interleukin- (IL-) 6 production were measured. NO production was tested in lipopolysaccharide-stimulated RAW 264.7 cells while in vivo studies were carried on croton oil-induced ear edema model. OFI extract and diglycoside isorhamnetin-glucosyl-rhamnoside (IGR) at 125 ng/mL suppressed the NO production in vitro (73.5 ± 4.8% and 68.7 ± 5.0%, resp.) without affecting cell viability. Likewise, IGR inhibited the ear edema (77.4 ± 5.7%) equating the indomethacin effects (69.5 ± 5.3%). Both IGR and OFI extract significantly inhibited the COX-2, TNF-α, and IL-6 production. IGR seems to be a suitable natural compound for development of new anti-inflammatory ingredient.

3-deoxysilybin exerts anti-inflammatory effects by suppressing NF-κB activation in lipopolysaccharide-stimulated RAW264.7 macrophages

3-deoxysilybin (3-DS), also known as (-)-isosilandrin A, is a natural flavonoid of Silybum marianum. This study was designed to investigate the anti-inflammatory effect and the underlying molecular mechanisms of 3-DS in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. 3-DS dose-dependently inhibited the production of NO and the expression of iNOS in LPS-stimulated RAW264.7 macrophages. 3-DS also inhibited the production of pro-inflammatory cytokines (MCP-1, TNF-α, IL-6, and IL-1β) in LPS-stimulated RAW264.7 macrophages. Moreover, 3-DS decreased the NF-κB DNA binding activity in LPS-stimulated RAW264.7 macrophages. Furthermore, 3-DS suppressed NF-κB activation by inhibiting the degradation of IκBα and nuclear translocation of p65 subunit of NF-κB in LPS-stimulated RAW264.7 macrophages. Taken together, the present study suggests for the first time that 3-DS may exhibit an anti-inflammatory effect through the suppression of NF-κB transcriptional activation in LPS-stimulated RAW264.7 macrophages.

UPLC-MS/MS method for determination of avicularin in rat plasma and its application to a pharmacokinetic study

A rapid, sensitive and selective ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was developed and validated for the determination and pharmacokinetic investigation of avicularin in rat plasma. Sample preparation was accomplished through a simple one-step deproteinization procedure with 0.2 mL of acetonitrile-methanol (9:1, v/v) to a 0.1 mL plasma sample. Plasma samples were separated by UPLC on an Acquity UPLC BEH C18 column using a mobile phase consisting of acetonitrile-0.1% formic acid in water with gradient elution. The total run time was 1.60 min and the elution of avicularin was at 1.20 min. The detection was performed on a triple quadrupole tandem mass spectrometer in the multiple reaction-monitoring (MRM) mode using the respective transitions m/z 434.1→301.3 for avicularin and m/z 237.2→194.3 for carbamazepine (IS), respectively. The calibration curve was linear over the range of 10-3000 ng/mL with a lower limit of quantitation (LLOQ) of 10 ng/mL. Mean recovery of avicularin in plasma was in the range of 84.2-89.5%. Intra-day and inter-day precision were both <12%. This method was successfully applied in pharmacokinetic study after intravenous administration of 5.0mg/kg avicularin in rats.

N-(p-Coumaryol)-Tryptamine Suppresses the Activation of JNK/c-Jun Signaling Pathway in LPS-Challenged RAW264.7 Cells

N-(p-Coumaryol) tryptamine (CT), a phenolic amide, has been reported to exhibit anti-oxidant and anti-inflammatory activities. However, the underlying mechanism by which CT exerts its pharmacological properties has not been clearly demonstrated. The objective of this study is to elucidate the anti-inflammatory mechanism of CT in lipopolysaccharide (LPS)-challenged RAW264.7 macrophage cells. CT significantly inhibited LPS-induced extracellular secretion of pro-inflammatory mediators such as nitric oxide (NO) and PGE2, and protein expressions of iNOS and COX-2. In addition, CT significantly suppressed LPS-induced secretion of pro-inflammatory cytokines such as TNF-α and IL-1β. To elucidate the underlying anti-inflammatory mechanism of CT, involvement of MAPK and Akt signaling pathways was examined. CT significantly attenuated LPS-induced activation of JNK/c-Jun, but not ERK and p38, in a concentration-dependent manner. Interestingly, CT appeared to suppress LPS-induced Akt phosphorylation. However, JNK inhibition, but not Akt inhibition, resulted in the suppression of LPS-induced responses, suggesting that JNK/c-Jun signaling pathway significantly contributes to LPS-induced inflammatory responses and that LPS-induced Akt phosphorylation might be a compensatory response to a stress condition. Taken together, the present study clearly demonstrates CT exerts anti-inflammatory activity through the suppression of JNK/c-Jun signaling pathway in LPS-challenged RAW264.7 macrophage cells.

Methyl p-Hydroxycinnamate Suppresses Lipopolysaccharide-Induced Inflammatory Responses through Akt Phosphorylation in RAW264.7 Cells

Derivatives of caffeic acid have been reported to possess diverse pharmacological properties such as anti-inflammatory, anti-tumor, and neuroprotective effects. However, the biological activity of methyl p-hydroxycinnamate, an ester derivative of caffeic acid, has not been clearly demonstrated. This study aimed to elucidate the anti-inflammatory mechanism of methyl p-hydroxycinnamate in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. Methyl p-hydroxycinnamate significantly inhibited LPS-induced excessive production of pro-inflammatory mediators such as nitric oxide (NO) and PGE₂ and the protein expression of iNOS and COX-2. Methyl p-hydroxycinnamate also suppressed LPS-induced overproduction of pro-inflammatory cytokines such as IL-1β and TNF-α. In addition, methyl p-hydroxycinnamate significantly suppressed LPS-induced degradation of IκB, which retains NF-κB in the cytoplasm, consequently inhibiting the transcription of pro-inflammatory genes by NF-κB in the nucleus. Methyl p-hydroxycinnamate exhibited significantly increased Akt phosphorylation in a concentration-dependent manner. Furthermore, inhibition of Akt signaling pathway with wortmaninn abolished methyl p-hydroxycinnamate-induced Akt phosphorylation. Taken together, the present study clearly demonstrates that methyl p-hydroxycinnamate exhibits anti-inflammatory activity through the activation of Akt signaling pathway in LPS-stimulated RAW264.7 macrophage cells.

Phosphorylation of Akt Mediates Anti-Inflammatory Activity of 1-p-Coumaroyl β-D-Glucoside Against Lipopolysaccharide-Induced Inflammation in RAW264.7 Cells

Hydroxycinnamic acids have been reported to possess numerous pharmacological activities such as antioxidant, anti-inflammatory, and anti-tumor properties. However, the biological activity of 1-p-coumaroyl β-D-glucoside (CG), a glucose ester derivative of p-coumaric acid, has not been clearly examined. The objective of this study is to elucidate the anti-inflammatory action of CG in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. In the present study, CG significantly suppressed LPS-induced excessive production of pro-inflammatory mediators such as nitric oxide (NO) and PGE2 and the protein expression of iNOS and COX-2. CG also inhibited LPS-induced secretion of pro-inflammatory cytokines, IL-1β and TNF-α. In addition, CG significantly suppressed LPS-induced degradation of IκB. To elucidate the underlying mechanism by which CG exerts its anti-inflammatory action, involvement of various signaling pathways were examined. CG exhibited significantly increased Akt phosphorylation in a concentration-dependent manner, although MAPKs such as Erk, JNK, and p38 appeared not to be involved. Furthermore, inhibition of Akt/PI3K signaling pathway with wortmannin significantly, albeit not completely, abolished CG-induced Akt phosphorylation and anti-inflammatory actions. Taken together, the present study demonstrates that Akt signaling pathway might play a major role in CG-mediated anti-inflammatory activity in LPS-stimulated RAW264.7 macrophage cells.

Syk and Src are major pharmacological targets of a Cerbera manghas methanol extract with kaempferol-based anti-inflammatory activity

ETHNOPHARMACOLOGICAL RELEVANCE

Cerbera manghas L. (Apocynaceae), a semi-mangrove medicinal plant distributed throughout tropical and subtropical countries, is traditionally known to possess analgesic, anti-inflammatory, anti-convulsant, cardiotonic, and hypotensive activity. In vitro and in vivo anti-inflammatory activities of a methanol extract of the leaves of Cerbera manghas and the underlying molecular mechanisms were investigated to validate the ethnopharmacological use of this plant.

MATERIALS AND METHODS

The effect of Cerbera manghas methanol extract (Cm-ME) on the production of inflammatory mediators and the induction of HCl/EtOH-treated gastritis was explored using macrophages, HEK293 cells, and ICR mice. The molecular targets of this extract and potential active components in Cm-ME were also investigated.

RESULTS

Cm-ME inhibited the production of nitric oxide (NO) in lipopolysaccharide (LPS)-treated RAW264.7 cells and peritoneal macrophages in a dose-dependent manner. This extract also suppressed the expression of NO synthase (iNOS) and cyclooxygenase (COX)-2. NF-κB-mediated enhancement of luciferase activity, nuclear translocation of p50 and p65, and phosphorylation of IκBα were markedly reduced by Cm-ME treatment. Direct enzyme assays, reporter gene assays, and immunoprecipitation analysis of kinases revealed Syk and Src as immunopharmacological targets of Cm-ME. Moreover, this extract strongly ameliorated the gastric symptoms induced by HCl/EtOH treatment of mice. Finally, HPLC analysis and pharmacological tests identified kaempferol as an active component of the extract with Src/Syk inhibitory activities.

CONCLUSION

Inhibition of Syk/Src and the NF-κB pathway by kaempferol could play a key role in the anti-inflammatory pharmacological action of Cerbera manghas.

Silibinin Inhibits LPS-Induced Macrophage Activation by Blocking p38 MAPK in RAW 264.7 Cells

We demonstrate herein that silibinin, a polyphenolic flavonoid compound isolated from milk thistle (Silybum marianum), inhibits LPS-induced activation of macrophages and production of nitric oxide (NO) in RAW 264.7 cells. Western blot analysis showed silibinin inhibits iNOS gene expression. RT-PCR showed that silibinin inhibits iNOS, TNF-α, and IL1β. We also showed that silibinin strongly inhibits p38 MAPK phosphorylation, whereas the ERK1/2 and JNK pathways are not inhibited. The p38 MAPK inhibitor abrogated the LPS-induced nitrite production, whereas the MEK-1 inhibitor did not affect the nitrite production. A molecular modeling study proposed a binding pose for silibinin targeting the ATP binding site of p38 MAPK (1OUK). Collectively, this series of experiments indicates that silibinin inhibits macrophage activation by blocking p38 MAPK signaling.

20S-dihydroprotopanaxadiol, a ginsenoside derivative, boosts innate immune responses of monocytes and macrophages

20S-dihydroprotopanaxadiol (2H-PPD) is a derivative of protopanaxadiol, a glycone of ginsenosides prepared from Panax ginseng. Although ginsenosides and acidic polysaccharides are known to be major active ingredients in ginseng, the immunopharmacological activities of their metabolites and derivatives have not been fully explored. In this study, we aimed to elucidate the regulatory action of 2H-PPD on the function of monocytes and macrophages in innate immune responses. 2H-PPD was able to boost the phagocytic uptake of fluorescein isothiocyanate-dextran in macrophages and enhance the generation of radicals (reactive oxygen species) in sodium nitroprusside-treated RAW264.7 cells. The surface levels of the costimulatory molecules such as CD80 and CD86 were also increased during 2H-PPD treatment. In addition, this compound boosted U937 cellcell aggregation induced by CD29 and CD43 antibodies, but not by cell-extracellular matrix (fibronectin) adhesion. Similarly, the surface levels of CD29 and CD43 were increased by 2H-PPD exposure. Therefore, our results strongly suggest that 2H-PPD has the pharmacological capability to upregulate the functional role of macrophages/monocytes in innate immunity.

Extracellular signal-regulated kinase is a direct target of the anti-inflammatory compound amentoflavone derived from Torreya nucifera

Amentoflavone is a biflavonoid compound with antioxidant, anticancer, antibacterial, antiviral, anti-inflammatory, and UV-blocking activities that can be isolated from Torreya nucifera, Biophytum sensitivum, and Selaginella tamariscina. In this study, the molecular mechanism underlying amentoflavone's anti-inflammatory activity was investigated. Amentoflavone dose dependently suppressed the production of nitric oxide (NO) and prostaglandin E₂ (PGE₂) in RAW264.7 cells stimulated with the TLR4 ligand lipopolysaccharide (LPS; derived from Gram-negative bacteria). Amentoflavone suppressed the nuclear translocation of c-Fos, a subunit of activator protein (AP)-1, at 60 min after LPS stimulation and inhibited the activity of purified and immunoprecipitated extracellular signal-regulated kinase (ERK), which mediates c-Fos translocation. In agreement with these results, amentoflavone also suppressed the formation of a molecular complex including ERK and c-Fos. Therefore, our data strongly suggest that amentoflavone's immunopharmacological activities are due to its direct effect on ERK.