Anti-inflammatory activities of an ethanol extract of Ecklonia stolonifera in lipopolysaccharide-stimulated RAW 264.7 murine macrophage cells

Lipids Extracted from Aptocyclus ventricosus Eggs Possess Immunoregulatory Effects on RAW264.7 Cells by Activating the MAPK and NF-κB Signaling Pathways

This study was conducted to evaluate the potential anti-inflammatory and immune-enhancement properties of lipids derived from Aptocyclus ventricosus eggs on RAW264.7 cells. Firstly, we determined the fatty acid compositions of A. ventricosus lipids by performing gas chromatography analysis. The results showed that A. ventricosus lipids contained saturated fatty acids (24.37%), monounsaturated fatty acids (20.90%), and polyunsaturated fatty acids (54.73%). They also contained notably high levels of DHA (25.91%) and EPA (22.05%) among the total fatty acids. Our results for the immune-associated biomarkers showed that A. ventricosus lipids had immune-enhancing effects on RAW264.7 cells. At the maximum dose of 300 µg/mL, A. ventricosus lipids generated NO (119.53%) and showed greater phagocytosis (63.69%) ability as compared with untreated cells. A. ventricosus lipids also upregulated the expression of iNOS, IL-1β, IL-6, and TNF-α genes and effectively upregulated the phosphorylation of MAPK (JNK, p38, and ERK) and NF-κB p65, indicating that these lipids could activate the MAPK and NF-κB pathways to stimulate macrophages in the immune system. Besides their immune-enhancing abilities, A. ventricosus lipids significantly inhibited LPS-induced RAW264.7 inflammatory responses via the NF-κB and MAPK pathways. The results indicated that these lipids significantly reduced LPS-induced NO production, showing a decrease from 86.95% to 38.89%. Additionally, these lipids downregulated the expression of genes associated with the immune response and strongly suppressed the CD86 molecule on the cell surface, which reduced from 39.25% to 33.80%. Collectively, these findings imply that lipids extracted from A. ventricosus eggs might have biological immunoregulatory effects. Thus, they might be considered promising immunomodulatory drugs and functional foods.

In Vitro Anti-Inflammatory and Skin Protective Effects of Codium fragile Extract on Macrophages and Human Keratinocytes in Atopic Dermatitis

Codium fragile has been traditionally used in oriental medicine to treat enterobiasis, dropsy, and dysuria, and it has been shown to possess many biological properties. Atopic dermatitis (AD) is one of the types of skin inflammation and barrier disruption, which leads to chronic inflammatory skin diseases. In the current investigation, the protective effects of C. fragile extract (CFE) on anti-inflammation and skin barrier improvement were investigated. In LPS-stimulated RAW 264.7 cells, nitric oxide generation and the expression levels of interleukin (IL)-1β, IL-4, IL-6, iNOS, COX-2, and tumor necrosis factor-alpha (TNF)-α were reduced by CFE. CFE also inhibited the phosphorylation of NF-κB-p65, ERK, p-38, and JNK. Additionally, CFE showed inhibitory activity on TSLP and IL-4 expression in HaCaT cells stimulated with TNF-α/interferon-gamma (IFN-γ). Enhanced expression of factors related to skin barrier function, FLG, IVL, and LOR, was confirmed. These findings implied that CFE may be used as a therapeutic agent against AD due to its skin barrier-strengthening and anti-inflammatory activities, which are derived from natural marine products.

Rehashing Our Insight of Seaweeds as a Potential Source of Foods, Nutraceuticals, and Pharmaceuticals

In a few Southeast Asian nations, seaweeds have been a staple of the cuisine since prehistoric times. Seaweeds are currently becoming more and more popular around the world due to their superior nutritional value and medicinal properties. This is because of rising seaweed production on a global scale and substantial research on their composition and bioactivities over the past 20 years. By reviewing several articles in the literature, this review aimed to provide comprehensive information about the primary and secondary metabolites and various classes of bioactive compounds, such as polysaccharides, polyphenols, proteins, and essential fatty acids, along with their bioactivities, in a single article. This review also highlights the potential of seaweeds in the development of nutraceuticals, with a particular focus on their ability to enhance human health and overall well-being. In addition, we discuss the challenges and potential opportunities associated with the advancement of pharmaceuticals and nutraceuticals derived from seaweeds, as well as their incorporation into different industrial sectors. Furthermore, we find that many bioactive constituents found in seaweeds have demonstrated potential in terms of different therapeutic attributes, including antioxidative, anti-inflammatory, anticancer, and other properties. In conclusion, seaweed-based bioactive compounds have a huge potential to play an important role in the food, nutraceutical, and pharmaceutical sectors. However, future research should pay more attention to developing efficient techniques for the extraction and purification of compounds as well as their toxicity analysis, clinical efficacy, mode of action, and interactions with regular diets.

Therapeutic Potential of Polyphenols and Other Micronutrients of Marine Origin

Polyphenols are compounds found in various plants and foods, known for their antioxidant and anti-inflammatory properties. Recently, researchers have been exploring the therapeutic potential of marine polyphenols and other minor nutrients that are found in algae, fish and crustaceans. These compounds have unique chemical structures and exhibit diverse biological properties, including anti-inflammatory, antioxidant, antimicrobial and antitumor action. Due to these properties, marine polyphenols are being investigated as possible therapeutic agents for the treatment of a wide variety of conditions, such as cardiovascular disease, diabetes, neurodegenerative diseases and cancer. This review focuses on the therapeutic potential of marine polyphenols and their applications in human health, and also, in marine phenolic classes, the extraction methods, purification techniques and future applications of marine phenolic compounds.

Ethanol Extract of Rosa laevigata Michx. Fruit Inhibits Inflammatory Responses through NF-κB/MAPK Signaling Pathways via AMPK Activation in RAW 264.7 Macrophages

The fruit of Rosa laevigata Michx. (FR), a traditional Chinese herb utilized for the treatment of a variety diseases, has notably diverse pharmacological activities including hepatoprotective, anti-oxidant, and anti-inflammatory effects. Despite ongoing research on illustrating the underlying anti-inflammatory mechanism of FR, the principal mechanism remained inadequately understood. In this study, we investigated in depth the molecular mechanism of the anti-inflammatory actions of the ethanol extract of FR (EFR) and its potential targets using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages in vitro. We showed that EFR effectively ameliorated the overproduction of inflammatory mediators and cytokines, as well as the expression of related genes. It was further demonstrated that LPS-induced activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) were significantly inhibited by pretreatment with EFR, accompanied by a concomitant decrease in the nuclear translocation of the p65 subunit of NF-κB and activator protein 1 (AP-1). In addition, EFR pretreatment potently prevented LPS-induced decreased phosphorylation of adenosine monophosphate-activated protein kinase (AMPK). Our data also revealed that the activation of AMPK and subsequent inhibition of the mammalian target of the rapamycin (mTOR) signaling pathway was probably responsible for the inhibitory effect of EFR on LPS-induced inflammatory responses, evidenced by reverse changes observed under the condition of AMPK inactivation following co-treatment with the AMPK-specific inhibitor Compound C. Finally, the main components with an anti-inflammatory effect in EFR were identified as madecassic acid, ellagic acid, quinic acid, and procyanidin C1 by LC-MS and testified based on the inhibition of NO production and inflammatory mediator expression. Taken together, our results indicated that EFR was able to ameliorate inflammatory responses via the suppression of MAPKs/NF-κB signaling pathways following AMPK activation, suggesting the therapeutic potential of EFR for inflammatory diseases.

Immunostimulatory activity of Hovenia dulcis branches extracts through TLR4/JNK-dependent macrophage activation and TLR4-dependent macrophage autophagy in RAW264.7 cells

Hovenia dulcis, one of the traditional medicinal plants, is currently being used as a functional ingredient for the development of health functional foods that protects the liver from alcohol damage in Korea. A variety of pharmacological effects of Hovenia dulcis have been reported so far, but studies on immune-enhancing activity are insufficient. Thus, in this study, we report that Hovenia dulcis branches (HDB) induce the activation of macrophages. HDB increased the production of immunostimulatory factors and phagocytosis in RAW264.7 cells. TLR4 inhibition blocked HDB-mediated production of immunostimulatory factors. In addition, the JNK inhibition reduced the HDB-mediated production of immunostimulatory factors, and the HDB-mediated JNK activation was blocked by the TLR4 inhibition. HDB increased the level of LC3-II and p62/SQSTM1. TLR4 inhibition blocked HDB-mediated increase in the level of LC3-II and p62/SQSTM1. These findings indicate that HDB may induce TLR4/JNK-dependent macrophage activation and TLR4-dependent macrophage autophagy.

Melaleuca rugulosa (Link) Craven Tannins: Appraisal of anti-inflammatory, radical scavenging activities, and molecular modeling studies

ETHNOPHARMACOLOGICAL RELEVANCE

Genus Melaleuca or tea tree species are well known to be an important source of biological active oils and extracts. The biological significance appears in their usage for treatment of several clinical disorder owing to their traditional uses as anti-inflammatory, antibacterial, antifungal, and cytotoxic activities.

AIM OF THE STUDY

Our study aimed to investigate the metabolic profile of the M. rugulosa polyphenol-rich fraction along with determination of its anti-inflammatory potential, free radical scavenging and antiaging activities supported with virtual understanding of the mode of action using molecular modeling strategy.

MATERIALS AND METHODS

The anti-inflammatory activity of the phenolic rich fraction was investigated through measuring its inhibitory activity against inflammatory mediators viz tumor necrosing factor receptor-2 (TNF-α) and cyclooxygenases 1/2 (COX-1/2) in a cell free and cell-based assays. Moreover, the radical scavenging activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC) and β-carotene assays, while the antiaging activity in anti-elastase, anti-collagenase, and anti-tyrosinase inhibitory assays. Finally, the biological findings were supported with molecular docking study using MOE software.

RESULTS

The chromatographic purification of the polyphenol-rich fraction of Melaleuca rugulosa (Link) Craven afforded fourteen phytoconstituents (1-14). The anti-inflammatory gauging experiments demonstrated inhibition of inflammatory-linked enzymes COX-1/2 and the TNF-α at low μg/mL levels in the enzyme-based assays. Further investigation of the underlying mechanism was inferred from the quantification of protein levels and gene expression in the lipopolysaccharide (LPS)-activated murine macrophages (RAW264.7) in vitro model. The results revealed the reduction of protein synthesis of COX-1/2 and TNF-α with the down regulation of gene expression. The cell free in vitro radical scavenging assessment of the polyphenol-rich fraction revealed a significant DPPH reduction, peroxyl radicals scavenging, and β-carotene peroxidation inhibition. Besides, the polyphenol-rich fraction showed a considerable inhibition of the skin aging-related enzymes as elastase, collagenase, and tyrosinase. Ultimately, the computational molecular modelling studies uncovered the potential binding poses and relevant molecular interactions of the identified polyphenols with their targeted enzymes. Particularly, terflavin C (8) which showed a favorable binding pose at the elastase binding pocket, while rosmarinic acid (14) demonstrated the best binding pose at the COX-2 catalytic domain. In short, natural polyphenols are potential candidates for the management of free radicals, inflammation, and skin aging related conditions.

CONCLUSION

Natural polyphenols are potential candidates for the management of free radicals, inflammation, and skin aging related conditions.

In-Depth Understanding of Ecklonia stolonifera Okamura: A Review of Its Bioactivities and Bioactive Compounds

Ecklonia stolonifera Okamura (ES) is mainly distributed in the coastal areas of the middle Pacific, around Korea and Japan, and has a long-standing edible value. It is rich in various compounds, such as polysaccharides, fatty acids, alginic acid, fucoxanthin, and phlorotannins, among which the polyphenol compound phlorotannins are the main active ingredients. Studies have shown that the extracts and active components of ES exhibit anti-cancer, antioxidant, anti-obesity, anti-diabetic, antibacterial, cardioprotective, immunomodulatory, and other pharmacological properties in vivo and in vitro. Although ES contains a variety of bioactive compounds, it is not widely known and has not been extensively studied. Based on its potential health benefits, it is expected to play an important role in improving the nutritional value of food both economically and medically. Therefore, ES needs to be better understood and developed so that it can be utilized in the development and application of marine medicines, functional foods, bioactive substances, and in many other fields. This review provides a comprehensive overview of the bioactivities and bioactive compounds of ES to promote in-depth research and a reference for the comprehensive utilization of ES in the future.

Structure-activity relationship in advanced glycation end products formation inhibitory activity of phlorotannins

The structure and inhibitory activity of advanced glycation end products (AGEs) formation were studied using six model compounds and seven phlorotannins isolated from brown alga Ecklonia stolonifera. As a result, it was inferred that AGEs formation inhibitory activity was stronger when electron-rich groups were present because of the addition of many oxygen atoms to the phlorotannins.

Potential Beneficial Effects of Sargassum spp. in Skin Aging

Seaweeds are receiving much attention as a rich source of bioactive compounds with cosmeceutical potential. Recent studies have revealed that Sargassum spp., a genus of brown algae in the family Sargassaceae, has multiple functions in preventing and improving skin aging. Sargassum spp. contains many bioactive compounds, such as fucoidan, fucoxanthin, terpenoids, flavonoids, and meroterpenoids. These Sargassum spp. extracts and derivative compounds have excellent potential for skincare, as they exhibit skin health-promoting properties, including antioxidants, anti-inflammation, whitening, skin barrier repair, and moisturizing. Therefore, searching for bioactive compounds in marine resources such as Sargassum spp. could be an attractive approach to preventing and improving skin aging. The current review focused on the various biological abilities of Sargassum extracts or derived compounds for anti-skin aging.

Anti-inflammatory effects of Torin2 on lipopolysaccharide-treated RAW264.7 murine macrophages and potential mechanisms

Context

Torin2 has various pharmacological properties. However, its anti-inflammatory activity has not been reported.

Objective

This study focused on the potential anti-inflammatory properties of Torin2 in lipopolysaccharide (LPS)-evoked RAW264.7 murine macrophages. The study aimed to shed light on the molecular mechanisms that ameliorate these effects.

Methods

Torin2 was applied to 100 ng/mL lipopolysaccharide-induced RAW 264.7 macrophages in vitro. Nitric oxide (NO) levels were detected using the Griess reagent kit. Prostaglandin E2 (PGE2), pro-inflammatory cytokines interleukin (IL)-1β, interleukin (IL)-6, and tumor necrosis factor in the supernatant fraction were determined using enzyme-linked immunosorbent assay (ELISA). Gene expression of pro-inflammatory cytokines, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) were tested using real-time quantitative polymerase chain reaction (qPCR). Cyclooxygenase-2 and inducible nitric oxide synthase proteins, phosphorylation of mitogen-activated protein kinase (MAPK) subgroups, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38, I-kappa-B-alpha (IκBα), and nuclear factor-kappa-B (NF-κB), and activation in extracts were detected via western blotting. Nuclear factor-kappa-B/p65 nuclear translocation was tested using an immunofluorescence assay.

Results

The results demonstrated that pre-treatment with Torin2 profoundly attenuated the lipopolysaccharide-stimulated levels of nitric oxide and prostaglandin E2, pro-inflammatory cytokines, messenger ribonucleic acid (mRNA), and protein expression of cyclooxygenase-2 and inducible nitric oxide synthase. Collectively, Torin2 pre-treatment notably weakened lipopolysaccharide-induced damage by reducing the phosphorylation of nuclear factor-kappa-B, p38, c-Jun N-terminal kinase, extracellular signal-regulated kinase proteins, and nuclear factor-kappa-B/p65 nuclear translocation.

Conclusion

Numerous pieces of evidence indicated that Torin2 reversed inflammatory activation by regulating nuclear factor-kappa-B and mitogen-activated protein kinase signaling pathways and provided a tentative potential candidate for preventing and treating inflammatory diseases.

Fabrication and characterization of Agarwood extract-loaded nanocapsules and evaluation of their toxicity and anti-inflammatory activity on RAW 264.7 cells and in zebrafish embryos

Aquilaria malaccensis has been traditionally used to treat several medical disorders including inflammation. However, the traditional claims of this plant as an anti-inflammatory agent has not been substantially evaluated using modern scientific techniques. The main objective of this study was to evaluate the anti-inflammatory effect of Aquilaria malacensis leaf extract (ALEX-M) and potentiate its activity through nano-encapsulation. The extract-loaded nanocapsules were fabricated using water-in-oil-in-water (w/o/w) emulsion method and characterized via multiple techniques including DLS, TEM, FTIR, and TGA. The toxicity and the anti-inflammatory activity of ALEX-M and the extract-loaded nanocapsules (ALEX-M-PNCs) were evaluated in-vitro on RAW 264.7 macrophages and in-vivo on zebrafish embryos. The nanocapsules demonstrated spherical shape with mean particle diameter of 167.13 ± 1.24 nm, narrow size distribution (PDI = 0.29 ± 0.01), and high encapsulation efficiency (87.36 ± 1.81%). ALEX-M demonstrated high viability at high concentrations in RAW 264.7 cells and zebrafish embryos, however, ALEX-M-PNCs showed relatively higher cytotoxicity. Both free and nanoencapsulated extract expressed anti-inflammatory effects through significant reduction of the pro-inflammatory mediator nitric oxide (NO) production in LPS/IFNγ-stimulated RAW 264.7 macrophages and zebrafish embryos in a concentration-dependent manner. The findings highlight that ALEX-M can be recognized as a potential anti-inflammatory agent, and its anti-inflammatory activity can be potentiated by nano-encapsulation. Further studies are warranted toward investigation of the mechanistic and immunomodulatory roles of ALEX-M.

The Anti-Allergic and Anti-Inflammatory Effects of Phlorotannins from the Edible Brown Algae, Ecklonia sp. and Eisenia sp

Because the number of people suffering from allergies has significantly increased, improved ways of treating these conditions by medical, pharmaceutical, and dietary means are required. Large numbers of studies on allergy have been conducted, and many anti-allergic compounds have been found. Phenolic compounds from terrestrial plants, including catechins and flavonoids, possess anti-allergic properties. Although polyphenols are present in some brown algae, their anti-allergic activities were not studied in detail before the 1990s. The focus was on the algal polyphenols, collectively called phlorotannins (eg., eckol, 6,6′-bieckol, 8,8′-bieckol, dieckol, and phlorofucofuroeckol-A), and research was conducted to clarify their anti-allergic activities. This review summarizes the anti-allergic effects of phlorotannins isolated from the brown alga, Eisenia nipponica, and related reports by other research groups.

Ginseng-Astragalus-oxymatrine injection ameliorates cyclophosphamide-induced immunosuppression in mice and enhances the immune activity of RAW264.7 cells

ETHNOPHARMACOLOGICAL SIGNIFICANCE

Ginseng quinquefolium (L.), Astragalus membranaceus, and Sophora flavescens Aiton are popular folk medicines in many Asian countries and regions. These three traditional Chinese herbs and their extracts have been reported to considerably enhance the immune function. G. quinquefolium (L.) is considered the king of herbs in China. Traditionally, G. quinquefolium (L.) is believed to replenish vitality, which is considered as immune enhancement in modern Chinese pharmacy. One of the main uses of Astragalus is immunity enhancement; S. flavescens and oxymatrine obtained from its extract have been used to treat leukopenia. Considering the pharmacological properties of Ginseng, Astragalus, and oxymatrine, we evaluated the immunopotentiation effects of their combination, Ginseng-Astragalus-oxymatrine (GAO), in the present study.

AIM OF THE STUDY

This study aimed to expand the clinical application of GAO and to preliminarily explore its mechanism of action by determining whether GAO injection can enhance immunity in vivo and in vitro.

METHODS

Overall, 17 major chemical components in GAO were analysed using HPLC and LC-MS. The immunity-enhancing effect of GAO was studied in the cyclophosphamide (CTX)-induced immunosuppressive mouse model and RAW 264.7 cells.

RESULTS

Quantitative analysis showed that the potential active components of GAO include at least ginsenosides, astragaloside IV, and oxymatrine. GAO could significantly improve the nonspecific immunity including the indices of the thymus and spleen, number of peripheral blood leukocytes, levels of TNF-α and IL-6, phagocytic function of macrophages, and cytotoxic activity of natural killer (NK) cells. Additionally, GAO enhanced the humoural immunity, characterised by the antibody production ability of B cells, and cellular immunity, characterised by the activity of T cells, in immunosuppressed mouse. Moreover, GAO could enhance the phagocytic and adhesion functions of RAW 264.7 cells, which may be related to the activation of reactive oxygen species and NF-κB signalling pathway.

CONCLUSION

GAO could dramatically ameliorate CTX-induced immunosuppression in mouse and stimulate the immune activity in RAW 264.7 cells possibly by activating the NF-κB signalling pathway.

Brown Algae Phlorotannins: A Marine Alternative to Break the Oxidative Stress, Inflammation and Cancer Network

According to the WHO, cancer was responsible for an estimated 9.6 million deaths in 2018, making it the second global leading cause of death. The main risk factors that lead to the development of this disease include poor behavioral and dietary habits, such as tobacco use, alcohol use and lack of fruit and vegetable intake, or physical inactivity. In turn, it is well known that polyphenols are deeply implicated with the lower rates of cancer in populations that consume high levels of plant derived foods. In this field, phlorotannins have been under the spotlight in recent years since they have shown exceptional bioactive properties, with great interest for application in food and pharmaceutical industries. Among their multiple bioactive properties, phlorotannins have revealed the capacity to interfere with several biochemical mechanisms that regulate oxidative stress, inflammation and tumorigenesis, which are central aspects in the pathogenesis of cancer. This versatility and ability to act either directly or indirectly at different stages and mechanisms of cancer growth make these compounds highly appealing for the development of new therapeutical strategies to address this world scourge. The present manuscript revises relevant studies focusing the effects of phlorotannins to counteract the oxidative stress-inflammation network, emphasizing their potential for application in cancer prevention and/or treatment.

Cirsilineol attenuates LPS-induced inflammation in both in vivo and in vitro models via inhibiting TLR-4/NFkB/IKK signaling pathway

The anti-inflammatory activity of cirsilineol in in vivo condition was assessed by measuring the relative organ weight, lung dry/wet weight ratio, protein concentration, and infiltration of inflammatory cells in bronchoalveolar lavage fluid. We estimated the myeloperoxidase activity and levels of cytokines, chemokines, and inflammatory markers to analyze the efficacy of cirsilineol against lipopolysaccharide (LPS)-induced lung inflammation. Furthermore, we quantified the gene expression of NFkB/IKK signaling molecules in cirsilineol-treated and untreated acute lung injury mice to confirm the anti-inflammatory property of cirsilineol. The lung histology was assessed with hematoxylin and eosin staining. Apart from in vivo experiments, in vitro tests with LPS-stimulated RAW 264.7 macrophages were also performed. Cell viability assay was performed in the presence and absence of LPS in RAW 264.7 macrophages to determine the cytotoxic effect of cirsilineol against macrophages. Reverse-transcription polymerase chain reaction (RT-PCR) analysis was done to analyze the gene expression of inflammatory markers in LPS-treated RAW 264.7 macrophages to prove that cirsilineol effectively inhibits inflammation in vitro. The results of our study prove that cirsilineol effectively inhibits inflammation in both in vivo and in vitro conditions. RT-PCR analysis results of NFkB/IKK signaling molecules clearly illustrate that cirsilineol inhibited the expression of NFkB/IKK signaling protein and thereby prevented inflammation in in vivo condition, and it is further confirmed with the results of inflammatory protein expression in vitro model. The lung histopathological studies authentically confirm that cirsilineol potentially prevented the mice from LPS-induced lung inflammation.

Immunomodulatory effect of pentagalloyl glucose in LPS-stimulated RAW264.7 macrophages and PAO1-induced Caenorhabditis elegans

Pentagalloyl glucose (PGG) is a valuable natural compound with an array of biological activities, but the immunomodulatory effect and mechanism have not been fully validated yet. In this study, to elucidate comprehensively the function of immunomodulation and its underlying mechanism of PGG in vitro and in vivo, two model systems were conducted, which including lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages cells and Pseudomonas aeruginosa (PAO1)-induced Caenorhabditis elegans (C. elegans). Current results showed that PGG significantly inhibited secretions of tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6) and mediator nitric oxide (NO) in LPS-stimulated RAW264.7 cells. In addition, the expression of genes nitric oxide synthase (iNOS), TNF-α, IL-1β and IL-6 in LPS- stimulated RAW264.7 cells was reduced by PGG. In vivo assay showed that lifespan of PAO1-induced C. elegans was enhanced significantly by 14.1% under the pre-treatment of PGG, which was abrogated in toxin sensitive mdt-15 mutant. Similarly, the PGG showed a benefit on 41.2% significant extension longevity in C. elegans under pathogenic PA14. And the nuclear localization of DAF-16 of strain TJ356 was significantly increased in PAO1-induced C. elegans by PGG. Further, PGG modulated several signaling pathways to enhance immunomodulation in C. elegans including DBL-1, DAF-2/DAF-16, and mitogen-activated protein (MAP) kinase pathways. Furthermore, other genes involved in immunomodulatory response in C. elegans were remarkably regulated such as lys-1, lys-2, spp-18, egl-9, and hif-1. Our study suggested that PGG have potential to develop into novel immunomodulatory nutraceutical.

Potential Anti-Aging Substances Derived from Seaweeds

Aging is a major risk factor for many chronic diseases, such as cancer, cardiovascular disease, and diabetes. The exact mechanisms underlying the aging process are not fully elucidated. However, a growing body of evidence suggests that several pathways, such as sirtuin, AMP-activated protein kinase, insulin-like growth factor, autophagy, and nuclear factor erythroid 2-related factor 2 play critical roles in regulating aging. Furthermore, genetic or dietary interventions of these pathways can extend lifespan by delaying the aging process. Seaweeds are a food source rich in many nutrients, including fibers, polyunsaturated fatty acids, vitamins, minerals, and other bioactive compounds. The health benefits of seaweeds include, but are not limited to, antioxidant, anti-inflammatory, and anti-obese activities. Interestingly, a body of studies shows that some seaweed-derived extracts or isolated compounds, can modulate these aging-regulating pathways or even extend lifespans of various animal models. However, few such studies have been conducted on higher animals or even humans. In this review, we focused on potential anti-aging bioactive substances in seaweeds that have been studied in cells and animals mainly based on their anti-aging cellular and molecular mechanisms.

Main bioactive phenolic compounds in marine algae and their mechanisms of action supporting potential health benefits

Given the growing tendency of consumers to choose products with natural ingredients, food industries have directed scientific research in this direction. In this regard, algae are an attractive option for the research, since they can synthesize a group of secondary metabolites, called phenolic compounds, associated with really promising properties and bioactivities. The objective of this work was to classify the major phenolic compounds, compare the effectiveness of the different extractive techniques used for their extraction, from traditional systems (like heat assisted extraction) to the most advance ones (such as ultrasound, microwave or supercritical fluid extraction); the available methods for identification and quantification; the stability of the enriched extract in phenolic compounds and the main bioactivities described for these secondary metabolites, to offer an overview of the situation to consider if it is possible and/or convenient an orientation of phenolic compounds from algae towards an industrial application.

Phlorotannins from Fucus vesiculosus: Modulation of Inflammatory Response by Blocking NF-κB Signaling Pathway

Due to their large spectrum of bioactive properties, much attention has recently been drawn to phlorotannins-i.e., phenolic compounds characteristic from brown macroalgae. This study aimed to evaluate the antioxidant and anti-inflammatory properties of F. vesiculosus phlorotannin extracts and purified fractions. Overall, the crude extract and its ethyl acetate fraction (EtOAc) showed good radical scavenging activity, particularly towards nitric oxide (NO•). Subsequent subfractions of EtOAc (F1 to F9) with different molecular weights were then shown to inhibit lipopolysaccharide-induced NO• production in macrophages, with stronger effects being observed for fractions of lower MWs. Of the three intracellular markers analyzed, inducible NO• synthase showed the highest sensitivity to almost all the phlorotannin-rich samples, followed by interleukin 1β and cyclooxygenase 2, which was only inhibited by F2. Furthermore, this subfraction inhibited the phosphorylation and degradation of inhibitory protein κBα, thus preventing the activation of NF-κB and blocking the inflammatory cascade at the transcriptional level. This sample was characterized by the presence of a major compound with a deprotonated molecular ion at m/z 507 with a fragmentation pattern coherent with that of a phlorotannin derivative. Overall, this work unveiled some of the mechanistic aspects behind the anti-inflammatory capacity of phlorotannins from F. vesiculosus, endorsing its use as a possible natural source of anti-inflammatory compounds.

Naturally Derived Heme-Oxygenase 1 Inducers and Their Therapeutic Application to Immune-Mediated Diseases

Heme oxygenase (HO) is the primary antioxidant enzyme involved in heme group degradation. A variety of stimuli triggers the expression of the inducible HO-1 isoform, which is modulated by its substrate and cellular stressors. A major anti-inflammatory role has been assigned to the HO-1 activity. Therefore, in recent years HO-1 induction has been employed as an approach to treating several disorders displaying some immune alterations components, such as exacerbated inflammation or self-reactivity. Many natural compounds have shown to be effective inductors of HO-1 without cytotoxic effects; among them, most are chemicals present in plants used as food, flavoring, and medicine. Here we discuss some naturally derived compounds involved in HO-1 induction, their impact in the immune response modulation, and the beneficial effect in diverse autoimmune disorders. We conclude that the use of some compounds from natural sources able to induce HO-1 is an attractive lifestyle toward promoting human health. This review opens a new outlook on the investigation of naturally derived HO-1 inducers, mainly concerning autoimmunity.

Algae Metabolites in Cosmeceutical: An Overview of Current Applications and Challenges

Cosmetics are widely used by people around the world to protect the skin from external stimuli. Consumer preference towards natural cosmetic products has increased as the synthetic cosmetic products caused adverse side effects and resulted in low absorption rate due to the chemicals' larger molecular size. The cosmetic industry uses the term "cosmeceutical", referring to a cosmetic product that is claimed to have medicinal or drug-like benefits. Marine algae have gained tremendous attention in cosmeceuticals. They are one of the richest marine resources considered safe and possessed negligible cytotoxicity effects on humans. Marine algae are rich in bioactive substances that have shown to exhibit strong benefits to the skin, particularly in overcoming rashes, pigmentation, aging, and cancer. The current review provides a detailed survey of the literature on cosmeceutical potentials and applications of algae as skin whitening, anti-aging, anticancer, antioxidant, anti-inflammation, and antimicrobial agents. The biological functions of algae and the underlying mechanisms of all these activities are included in this review. In addition, the challenges of using algae in cosmeceutical applications, such as the effectiveness of different extraction methods and processing, quality assurance, and regulations concerning extracts of algae in this sector were also discussed.

Isosteroid alkaloids with different chemical structures from Fritillariae cirrhosae bulbus alleviate LPS-induced inflammatory response in RAW 264.7 cells by MAPK signaling pathway

Isosteroid alkaloids, natural products from Fritillariae Cirrhosae Bulbus, are well known for its antitussive, expectorant, anti-asthmatic and anti-inflammatory properties. However, the anti-inflammatory effect and its mechanism have not been fully explored. In this study, the anti-inflammatory activitives and the potential mechanisms of five isosteroid alkaloids from F. Cirrhosae Bulbus were investigated in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells. The pro-inflammatory mediators and cytokines were measured by Griess reagent, ELISA and qRT-PCR. The expression of MAPKs was investigated by western blotting. Treatment with the five isosteroid alkaloids in appropriate concentrations could reduce the production of nitric oxide (NO), tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) in supernatant, and suppressed the mRNA expressions of TNF-α and IL-6. Meanwhile, the five isosteroid alkaloids significantly inhibited the phosphorylated activation of mitogen activated protein kinase (MAPK) signaling pathways, including extracellular signal-regulated kinase (ERK1/2), p38 MAPK and c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK). These results demonstrated that isosteroid alkaloids from F. Cirrhosae Bulbus exert anti-inflammatory effects by down-regulating the level of inflammatory mediators via mediation of MAPK phosphorylation in LPS-induced RAW264.7 macrophages, thus could be candidates for the prevention and treatment of inflammatory diseases.

Seaweeds-derived compounds modulating effects on signal transduction pathways: A systematic review

BACKGROUND

Recently, the study of marine natural products has gained interest due to their relevant biological activities. Specially, seaweeds produce bioactive compounds that could act as modulators of cell signaling pathways involved in a plethora of diseases. Thereby, the description of the molecular mechanisms by which seaweeds elicit its biological functions will certainly pave the way to the pharmacological development of drugs.

AIM

This review describes the molecular mechanisms by which seaweeds act and its possible utilization in the design of new drugs.

METHODS

This review was conducted according to the PRISMA-P guidelines for systematic reviews. Two independent authors searched into four different databases using combinations of keywords. Two more authors selected the articles following the eligibility criteria. Information extraction was conducted by two separated authors and entered into spreadsheets. Methodological quality and risk of bias were determined applying a 12-question Risk of Bias criteria tool.

RESULTS AND DISCUSSION

We found 2360 articles (SCOPUS: 998; PubMed: 678; Wiley: 645 and EBSCO: 39) using the established keywords, of which 113 articles fit the inclusion criteria and were included in the review. This work comprises studies in cell lines, and animal models, any clinical trial was excluded. The articles were published from 2005 up to March 31st 2018. The biggest amount of articles was published in 2017. Furthermore, the seaweeds tested in the studies were collected in 15 countries, mainly in Eastern countries. We found that the main modulated signaling pathways by seaweeds-derivate extracts and compounds were: L-Arginine/NO, TNF-α, MAPKs, PI3K/AKT/GSK, mTOR, NF-κB, extrinsic and intrinsic apoptosis, cell cycle, MMPs and Nrf2. Finally, the articles we analyzed showed moderate risk of bias in almost all the parameters evaluated. However, the studies fail to describe the place and characteristics of sample collection, the sample size, and the blindness of the experimental design.

CONCLUSION

In this review we identified and summarized relevant information related to seaweed-isolated compounds and extracts having biological activity; their role in different signal pathways to better understand their potential to further development of cures for cancer, diabetes, and inflammation-related diseases.

Anti-Inflammatory Effect of Ecklonia cava Extract on Porphyromonas gingivalis Lipopolysaccharide-Stimulated Macrophages and a Periodontitis Rat Model

Ecklonia cava, an edible marine brown alga (Laminariaceae), is a rich source of phlorotannins. This study aimed to investigate the anti-inflammatory effect of Ecklonia cava ethanol extract (ECE, dieckol 10.6%, w/w) on Porphyromonas gingivalis lipopolysaccharide-stimulated inflammation in RAW 264.7 cells and in ligature-induced periodontitis in rats. The levels of nitric oxide (NO) and prostaglandin E2 were decreased by more than half on treatment with 100 μg/mL ECE. Downregulated tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 gene expression confirmed the anti-inflammatory properties of ECE. ECE treatment upregulated heme oxygenase-1 (HO-1) expression by 6.3-fold and increased HO-1/nuclear factor erythroid 2-related factor 2 (Nrf-2) signaling decreased nuclear factor-κB (NF-κB) translocation. ECE administration (400 mg/kg) significantly reduced gingival index, restricted tooth mobility, and prevented alveolar bone loss (p < 0.05). These beneficial effects were due to decreased inflammatory cell infiltration, IL-1β production, and matrix metalloproteinase expression in gingival tissues. The ratio of receptor activator of nuclear factor-κB ligand (RANKL)/osteoprotegerin, a biomarker of periodontitis and osteolysis, was significantly decreased by ECE administration (p < 0.05). Thus, ECE has potential therapeutic effects for the alleviation of periodontal disease.

Anti-inflammatory effects of dicaffeoylquinic acids from Ilex kudingcha on lipopolysaccharide-treated RAW264.7 macrophages and potential mechanisms

Increasing evidence has shown that dicaffeoylquinic acids (DiCQAs) have anti-inflammatory activity. However, the underlying molecular mechanisms of the anti-inflammatory effects of DiCQAs are still unclear. In the present study, the anti-inflammatory effects of DiCQAs from the leaves of Ilex kudingcha and the potential molecular mechanisms on LPS-induced inflammatory responses in RAW264.7 macrophage cells were investigated. The results showed that pretreatment with DiCQAs could suppress the production of NO, PGE₂ and also pro-inflammatory cytokines TNF-α, IL-1β and IL-6, and the mRNA expression of two major inflammatory mediators of COX-2 and iNOS. The phosphorylated IκBα, ERK, JNK and p38 proteins in LPS-treated cells were significantly increased, which could be reversed by pretreatment with DiCQAs in a concentration-dependent manner. Taken together, the results suggest that DiCQAs from I. kudingcha have potent anti-inflammatory effects on LPS-induced inflammatory responses by inhibiting the NF-κB and MAPKs pathways and may be a prophylactic for inflammation.

Anti-Inflammatory Effect of a Polyphenol-Enriched Fraction from Acalypha wilkesiana on Lipopolysaccharide-Stimulated RAW 264.7 Macrophages and Acetaminophen-Induced Liver Injury in Mice

A polyphenol-enriched fraction (PEF) from Acalypha wilkesiana, whose leaves have been traditionally utilized for the treatment of diverse medical ailments, was investigated for the anti-inflammatory effect and molecular mechanisms by using lipopolysaccharide- (LPS-) stimulated RAW 264.7 macrophages and acetaminophen- (APAP-) induced liver injury mouse model. Results showed that PEF significantly attenuated LPS-induced nitric oxide (NO) and prostaglandin E₂ (PGE₂) production and suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) in RAW 264.7 macrophages. PEF also reduced the secretion of proinflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin- (IL-) 1β, and IL-6 in LPS-stimulated RAW 264.7 macrophages. Moreover, PEF potently inhibited LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs) as well as the activation of nuclear factor-κB (NF-κB) by preventing the degradation of inhibitor κB-α (IκB-α). In vivo, PEF pretreatment ameliorated APAP-induced liver injury and hepatic inflammation, as presented by decreased hepatic damage indicators and proinflammatory factors at both plasma and gene levels. Additionally, PEF pretreatment remarkably diminished Toll-like receptor 3 (TLR3) and TLR4 expression and the subsequent MAPKs and NF-κB activation. HPLC analysis revealed that two predominantly polyphenolic compounds present in PEF were geraniin and corilagin. These results indicated that PEF has an anti-inflammatory effect, and its molecular mechanisms may be involved in the inactivation of the TLR/MAPK/NF-κB signaling pathway, suggesting the therapeutic potential of PEF for inflammatory diseases.

Antioxidant and anti-inflammatory effects of polyphenols extracted from Ilex latifolia Thunb

To promote the rational and effective application of Ilex latifolia Thunb., a Chinese bitter tea widely consumed as a health beverage, polyphenols were extracted from its leaves and their cellular antioxidant activity (CAA) and anti-inflammatory effect against mouse macrophage RAW 264.7 cells were analyzed. Results showed that the antioxidant capacity of polyphenols was high, and their CAA values in PBS wash and no PBS wash protocols were 6871.42 ± 85.56 and 25161.61 ± 583.55 μmol QE (quercetin equivalents)/100 g phenolic extracts, respectively. In addition, polyphenols from I. latifolia displayed strong inhibition on LPS-induced NO-production in RAW 264.7 cells. Polyphenol treatment inhibited the release of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) induced by LPS in a dose-dependent manner by ELISA and mRNA expression analysis. Western blot results showed that the anti-inflammatory activity of polyphenols from I. latifolia might be exerted through inhibiting the activation of MAPKs (ERK and JNK) and NF-κB to decrease NO, COX-2 and pro-inflammatory cytokines production. Thus, the polyphenol enriched extracts from I. latifolia are a good source of natural antioxidants with a beneficial effect against inflammation, and they may be applied as a food supplement and/or functional ingredient.

Maydis Stigma Elicits Analgesia and Blocks Edema in Mice and Inhibits Inflammation in Macrophages

Maydis Stigma (MS) is an herb traditionally used in many parts of the world. Previous studies have reported that MS plays a role in several biological activities, including antidiabetic and anticancer activities. However, the effects of a MS ethanolic extract (MSE) on the anti-inflammatory cellular mechanism remain unclear. Here, we investigated the anti-inflammatory properties of MSE and its molecular mechanism both in vitro and in vivo. The effects of MSE on the production of inflammatory mediators, cytokines, and related proteins and the identification of target genes were determined using LPS-stimulated macrophages. We also determined the analgesic and anti-inflammatory effects of MSE by examining acetic acid-induced writhing responses and xylene-induced ear edema in mice. Our results indicated that MSE markedly decreased iNOS and COX-2 levels without causing cytotoxicity and suppressed the secretion of NO in LPS-stimulated macrophages. MSE also inhibited the production of proinflammatory cytokines, such as TNF-[Formula: see text], IL-6, and IL-1[Formula: see text], and induced the expression of HO-1. Moreover, MSE treatment significantly reduced the LPS-stimulated activation of MAPK, NF-[Formula: see text]B, and AP-1. Furthermore, MSE exerted an analgesic effect on the acetic acid-induced abdominal writhing response test and an anti-inflammatory effect on xylene-induced ear edema in ICR mice. Finally, we investigated the components of MSE using UPLC-ESI-MS and found that it contains the maysin as a marker component. Overall, these observations demonstrate that MSE has anti-inflammatory and antinociceptive effects both in vitro and in vivo, which may provide new scientific evidence for its use as a potential therapeutic agent for the treatment of inflammation.

Polysaccharide from wheat bran induces cytokine expression via the toll-like receptor 4-mediated p38 MAPK signaling pathway and prevents cyclophosphamide-induced immunosuppression in mice

Wheat bran-derived polysaccharides have attracted particular attention due to their immunomodulatory effects. However, the molecular mechanisms underlying their functions are poorly understood. The current study was designed to examine the effect of wheat bran polysaccharide (WBP) on RAW 264.7 cells and the underlying signaling pathways, which have not been explored. In addition, we also investigated the immuno-enhancement effects of WBP on cyclophosphamide (CTX)-induced immunosuppression in mice. WBP significantly increased the concentrations of intracellular nitric oxide (NO) and cytokines such as prostaglandin E₂ (PGE₂) and tumor necrosis factor-α (TNF-α) in RAW 264.7 cells. The result of RT-PCR analysis indicated that WBP also enhanced inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and TNF-α expression. Further analyses demonstrated that WBP rapidly activated phosphorylated p38 mitogen-activated protein kinase (MAPK) and the transcriptional activities of activator protein-1 (AP-1) and nuclear factor (NF)-κB via toll-like receptor 4 (TLR4). Furthermore, in vivo experiments revealed that WBP increased the spleen and thymus indices significantly, and markedly promoted the production of the serum cytokines IL-2 and IFN-γ in CTX-induced immunosuppressed mice. Taken together, these results suggest that WBP can improve immunity by enhancing immune function, and could be explored as a potential immunomodulatory agent in functional food.

Structural Characterization of a Novel Polysaccharide from Lepidium meyenii (Maca) and Analysis of Its Regulatory Function in Macrophage Polarization in Vitro

In our previous study, three novel polysaccharides, named MC-1, MC-2, and MC-3, were separated from the roots of maca (Lepidium meyenii), which is a food source from the Andes region. The structural information and immunomodulatory activity of MC-1 were then investigated. The structure and activity of MC-2 are still unknown. In this study, structural characterization revealed that MC-2 has an average molecular weight of 9.83 kDa and is composed of arabinose (20.9%), mannose (4.5%), glucose (71.9%), and galactose (2.7%). The main linkage types of MC-2 were proven to be (1→5)-α-l-Ara, (1→3)-α-l-Man, (1→)-α-d-Glc, (1→4)-α-d-Glc, (1→6)-α-d-Glc, and (1→6)-β-d-Gal by methylation and NMR analyses. Congo red assay showed that MC-2 possesses a triple-helix conformation. Immunostimulating assays indicated that MC-2 could induce M1 polarization of original macrophages and convert M2 macrophages into M1 phenotype. Although MC-2 could not shift M1 macrophages into M2, it could still inhibit inflammatory reactions induced by lipopolysaccharide. Furthermore, Toll-like receptor 2, tTll-like receptor 4, complement receptor 3, and mannose receptor were confirmed as the membrane receptors for MC-2 on macrophages. These results indicate that MC-2 could potentially be used toward hypoimmunity and tumor therapies.

Evaluation of anti-inflammatory activity of compounds isolated from the rhizome of Ophiopogon japonicas

Background

Ophiopogon japonicas (L.f) Ker-Gawl has been used as a traditional Chinese medicine to cure acute and chronic inflammation and cardiovascular diseases including thrombotic diseases for thousands of years. Previous phytochemical studies showed that O. japonicus contained compounds with anti-inflammatory activity. The aim of this study was to identify and isolate compounds with anti-inflammatory activity from the rhizome of O. japonicas.

Methods

Compounds were isolated by various column chromatography and their structures were identified in terms of nuclear magnetic resonance spectrum (NMR) and mass spectrum (MS). To measure the anti-inflammatory effects of thirteen compounds in LPS-induced RAW 264.7 macrophage cells, we used the following methods: cell viability assay, nitric oxide assay, enzyme-linked immunosorbent assay, quantitative real-time PCR analysis and western blotting analysis.

Results

One new and twelve known compounds (mainly homoisoflavonoids) were extracted from O. japonicas, in which 4′-O-Demethylophiopogonanone E (10) was considered as a new compound, additionally, compounds 4-O-(2-Hydroxy-1- hydroxymethylethyl)-dihydroconiferyl alcohol (2) and 5,7-dihydroxy-6-methyl-3-(2′, 4′-dihydroxybenzyl) chroman-4-one (12) were isolated from the rhizome of O. japonicas for the first time. The isolated compounds Oleic acid (3), Palmitic acid (4), desmethylisoophiopogonone B [5,7-dihydroxy-3-(4′-hydroxybenzyl)-8- methyl- chromone] (5), 5,7-dihydroxy-6-methyl-3-(4′-hydroxybenzyl) chromone (7) and 10 significantly suppressed the production of NO in LPS-induced RAW 264.7 cells. Especially compound 10 showed the strongest effect against the production of the pro-inflammatory cytokine IL-1β and IL-6 with the IC₅₀ value of 32.5 ± 3.5 μg/mL and 13.4 ± 2.3 μg/mL, respectively. Further analysis elucidated that the anti-inflammatory activity of compound 10 might be exerted through inhibiting the phosphorylation of ERK1/2 and JNK in MAPK signaling pathways to decrease NO and pro-inflammatory cytokines production.

Conclusions

Our results indicated that 4′-O-Demethylophiopogonanone E can be considered as a potential source of therapeutic medicine for inflammatory diseases.

Potential anti-inflammatory natural products from marine algae

Inflammatory diseases have become one of the leading causes of health issue throughout the world, having a considerable influence on healthcare costs. With the emerging developments in natural product, synthetic and combinatorial chemistry, a notable success has been achieved in discovering natural products and their synthetic structural analogs with anti-inflammatory activity. However, many of these therapeutics have indicated detrimental side effects upon prolonged usage. Marine algae have been identified as an underexplored reservoir of unique anti-inflammatory compounds. These include polyphenols, sulfated polysaccharides, terpenes, fatty acids, proteins and several other bioactives. Consumption of these marine algae could provide defense against the pathophysiology of many chronic inflammatory diseases. With further investigation, algal anti-inflammatory phytochemicals have the potential to be used as therapeutics or in the synthesis of structural analogs with profound anti-inflammatory activity with reduced side effects. The current review summarizes the latest knowledge about the potential anti-inflammatory compounds discovered from marine algae.

Anti-Inflammatory Effect of Rhapontici Radix Ethanol Extract via Inhibition of NF-κB and MAPK and Induction of HO-1 in Macrophages

Rhapontici Radix (RR) has been used in traditional medicine in East Asia and has been shown to have various beneficial effects. However, its biological properties or mechanism on inflammation-related diseases is unknown. The goal of this study was to determine the anti-inflammatory activity and underlying molecular mechanisms of Rhapontici Radix ethanol extract (RRE). The inhibitory effect of RRE on the production of NO, cytokines, inflammatory-related proteins, and mRNAs in LPS-stimulated macrophages was determined by the Griess assay, ELISA, Western blot analysis, and real-time RT-PCR, respectively. Our results indicate that treatment with RRE significantly inhibited the secretion of NO and inflammatory cytokines in RAW 264.7 cells and mouse peritoneal macrophages without cytotoxicity. We also found that RRE strongly suppressed the expression of iNOS and COX-2 and induced HO-1 expression. It also prevented nuclear translocation of NF-κB by inhibiting the phosphorylation and degradation of IκBα. Furthermore, the phosphorylation of MAPKs in LPS-stimulated RAW 264.7 cells was significantly inhibited by RRE. These findings suggest that RRE may operate as an effective anti-inflammatory agent by inhibiting the activation of NF-κB and MAPK signaling pathways and inducing HO-1 expression in macrophages. Our results suggest that RRE has potential value as candidate to inflammatory therapeutic phytomedicine.

Synergistic Effect of Compounds from a Chinese Herb: Compatibility and Dose Optimization of Compounds from N-Butanol Extract of Ipomoea stolonifera

The herbal medicine Ipomoea stolonifera (I. stolonifera) has previously been shown to have considerable anti-inflammatory potential in vivo and in vitro. To establish a method for exploring the synergistic effects of multiple compounds, we study the compatibility and dose optimization of compounds isolated from n-butanol extract of I. stolonifera (BE-IS). Raw264.7 cell was treated with lipopolysaccharide (LPS) in the presence of compounds from BE-IS, namely scopoletin, umbelliferone, esculetin, hesperetin and curcumin, using the orthogonal design, uniform design and median-effect method. To verify the best efficacy of principal constituents in vivo, the uniform design was used in the croton oil-induced mouse ear edema model. The results from LPS-induced the production of prostaglandin E2 (PGE2) show that, esculetin, curcumin and hesperetin were the principal constituents that had synergistic effects when used at the optimal ratio. Additionally, the principal constituents were found to work synergistically in the croton oil-induced mouse ear edema model at low doses. It turned out that the three experimental optimization and analysis methods (orthogonal design, uniform design and median-effect method) can be effectively used to solve both compatibility and dose optimization for combined use of multiple compounds.

5-Methoxyl Aesculetin Abrogates Lipopolysaccharide-Induced Inflammation by Suppressing MAPK and AP-1 Pathways in RAW 264.7 Cells

For the first time, a pale amorphous coumarin derivative, 5-methoxyl aesculetin (MOA), was isolated from the dried bark of Fraxinus rhynchophylla Hance (Oleaceae). MOA modulates cytokine expression in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, but the precise mechanisms are still not fully understood. We determined the effects of MOA on the production of inflammatory mediators and pro-inflammatory cytokines in the LPS-induced inflammatory responses of RAW 264.7 macrophages. MOA significantly inhibited the LPS-induced production of nitric oxide (NO), prostaglandin E₂ (PGE₂), tumor necrosis factor-α (TNF-α), interleukin-6, and interleukin-1β. It also effectively attenuated inducible nitric oxide (NO) synthase, cyclooxygenase-2, and TNF-α mRNA expression and significantly decreased the levels of intracellular reactive oxygen species. It inhibited phosphorylation of the extracellular signal-regulated kinase (ERK1/2), thus blocking nuclear translocation of activation protein (AP)-1. In a molecular docking study, MOA was shown to target the binding site of ERK via the formation of three hydrogen bonds with two residues of the kinase, which is sufficient for the inhibition of ERK. These results suggest that the anti-inflammatory effects of MOA in RAW 264.7 macrophages derive from its ability to block both the activation of mitogen-activated protein kinases (MAPKs) and one of their downstream transcription factors, activator protein-1 (AP-1). Our observations support the need for further research into MOA as a promising therapeutic agent in inflammatory diseases.

Sargaquinoic Acid Inhibits TNF-α-Induced NF-κB Signaling, Thereby Contributing to Decreased Monocyte Adhesion to Human Umbilical Vein Endothelial Cells (HUVECs)

Sargaquinoic acid (SQA) has been known for its antioxidant and anti-inflammatory properties. This study investigated the effects of SQA isolated from Sargassum serratifolium on the inhibition of tumor necrosis factor (TNF)-α-induced monocyte adhesion to human umbilical vein endothelial cells (HUVECs). SQA decreased the expression of cell adhesion molecules such as intracellular adhesion molecule-1 and vascular cell adhesion molecule-1 as well as chemotactic cytokines such as interleukin-8 and monocyte chemoattractant protein-1 in TNF-α-treated HUVECs. As a result, SQA prevented monocyte adhesion to TNF-α-induced adhesion. SQA also inhibited TNF-α-induced nuclear factor kappa B (NF-κB) translocation into the nucleus by preventing proteolytic degradation of inhibitor κB-α. Overall, SQA protects against TNF-α-induced vascular inflammation through inhibition of the NF-κB pathway in HUVECs. These data suggest that SQA may be used as a therapeutic agent for vascular inflammatory diseases such as atherosclerosis.

Phlorofucofuroeckol B suppresses inflammatory responses by down-regulating nuclear factor κB activation via Akt, ERK, and JNK in LPS-stimulated microglial cells

Microglial activation has been implicated in many neurological disorders for its inflammatory and neurotrophic effects. In this study, we investigated the effects of phlorofucofuroeckol B (PFF-B) isolated from Ecklonia stolonifera, on the production of inflammatory mediators in lipopolysaccharide (LPS)-stimulated microglia. PFF-B decreased secretion of pro-inflammatory cytokines including tumor necrosis factor α, interleukin (IL)-1β, and IL-6 and the expression of pro-inflammatory proteins such as cyclooxygenase-2 and inducible nitric oxide synthase in LPS-stimulated BV-2 cells. Profoundly, PFF-B inhibited activation of nuclear factor kappaB (NF-κB) by preventing the degradation of inhibitor κB-α (IκB-α), which led to prevent the nuclear translocation of p65 NF-κB subunit. Moreover, PFF-B inhibited the phosphorylation of Akt, ERK, and JNK. These results indicate that the anti-inflammatory effect of PFF-B on LPS-stimulated microglial cells is mainly regulated by the inhibition of IκB-α/NF-κB and Akt/ERK/JNK pathways. Our study suggests that PFF-B can be considered as a therapeutic agent against neuroinflammation by inhibiting microglial activation.

Anti-inflammatory activity of guluronate oligosaccharides obtained by oxidative degradation from alginate in lipopolysaccharide-activated murine macrophage RAW 264.7 cells

Alginate has notably diverse pharmacological activities. The present study investigated the anti-inflammatory activity of the guluronate oligosaccharides prepared by oxidative degradation (GOS-OD) from alginate. GOS-OD significantly attenuated the production of nitric oxide (NO), prostaglandin E2 (PGE2), and reactive oxygen species (ROS), the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and the secretion of pro-inflammatory cytokines in lipopolysaccharide (LPS)-activated murine macrophage RAW 264.7 cells. Moreover, GOS-OD potently decreased the binding of LPS to the cell surface and LPS-induced Toll-like receptor 4 (TLR4) and cluster of differentiation (CD) 14 expression. Additionally, GOS-OD could remarkably inhibit the LPS-induced activation of nuclear factor (NF)-κB and mitogen-activated protein (MAP) kinase pathways in RAW 264.7 cells. These results indicate that GOS-OD may reduce the LPS-stimulated inflammatory responses through blocking the activation of NF-κB and MAP kinases, suggesting that GOS-OD may be considered as a potential nutraceutical for inflammation.

Anti-inflammatory and protective properties of daphnetin in endotoxin-induced lung injury

Uncontrolled inflammatory responses cause tissue injury and severe immunopathology. Pharmacological interference of intracellular pro-inflammatory signaling may confer a therapeutic benefit under these conditions. Daphnetin, a natural coumarin derivative, has been used to treat inflammatory diseases including bronchitis. However, the protective effect of daphnetin in inflammatory airway disorders has yet to be determined, and the molecular basis for its anti-inflammatory properties is unknown. This paper shows that daphnetin treatment conferred substantial protection from endotoxin-induced acute lung injury (ALI), in parallel with reductions in the production of inflammatory mediators, symptoms of airway response, and infiltration of inflammatory cells. Further studies indicate that activation of macrophage and human alveolar epithelial cells in response to lipopolysaccharide (LPS) was remarkably suppressed by daphnetin, which was related to the down-regulation of NF-κB-dependent signaling events. Importantly, this study demonstrates that TNF-α-induced protein 3 (TNFAIP3), also known as A20, was significantly induced by daphnetin, which appeared to be largely responsible for the down-regulation of NF-κB activity through modulation of nondegradative TRAF6 ubiquitination. Accordingly, the deletion of TNFAIP3 in primary macrophages reversed daphnetin-elicited inhibition of immune response, and the beneficial effect of daphnetin in the pathogenesis of ALI was, partially at least, abrogated by TNFAIP3 knockdown. These findings demonstrate the anti-inflammatory and protective functions of daphnetin in endotoxin-induced lung inflammation and injury and also reveal the key mechanism underlying its action in vitro as well as in vivo.

An ethyl acetate fraction derived from Houttuynia cordata extract inhibits the production of inflammatory markers by suppressing NF-кB and MAPK activation in lipopolysaccharide-stimulated RAW 264.7 macrophages

Background

Houttuynia cordata Thunb. (Saururaceae) has been used in traditional medicine for treatment of inflammatory diseases. This study evaluated the anti-inflammatory effects of an ethyl acetate fraction derived from a Houttuynia cordata extract (HCE-EA) on the production of inflammatory mediators and the activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages.

Methods

To measure the effects of HCE-EA on pro-inflammatory cytokine and inflammatory mediator’s expression in RAW 264.7 cells, we used the following methods: cell viability assay, Griess reagent assay, enzyme-linked immunosorbent assay, real-time polymerase chain reaction and western blotting analysis.

Results

HCE-EA downregulated nitric oxide (NO), prostaglandin E₂ (PGE₂), tumor necrosis factor-α (TNF-α), and interleukin (IL-6) production in the cells, as well as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Furthermore, HCE-EA suppressed nuclear translocation of the NF-κB p65 subunit, which correlated with an inhibitory effect on IκBα (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha) phosphorylation. HCE-EA also attenuated the activation of MAPKs (p38 and JNK).

Conclusions

Our results suggest that the anti-inflammatory properties of HCE-EA may stem from the inhibition of pro-inflammatory mediators via suppression of NF-κB and MAPK signaling pathways.

Anti-inflammatory effects of sargachromenol-rich ethanolic extract of Myagropsis myagroides on lipopolysaccharide-stimulated BV-2 cells

BACKGROUND

Excessive pro-inflammatory cytokine production from activated microglia contributes to neurodegenerative diseases, thus, microglial inactivation may delay the progress of neurodegeneration by attenuating the neuroinflammation. Among 5 selected brown algae, we found the highest antioxidant and anti-neuroinflammatory activities from Myagropsis myagroides ethanolic extract (MME) in lipopolysaccharide (LPS)-stimulated BV-2 cells.

METHODS

The levels of nitric oxide (NO), prostaglandin E2 (PGE2), and pro-inflammatory cytokines were measured by Griess assay and enzyme linked immunesorbent assay. The levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), mitogen-activated protein kinases (MAPKs), and Akt were measured using Western blot. Nuclear translocation and transcriptional activation of nuclear factor-κB (NF-κB) were determined by immunefluorescence and reporter gene assay, respectively.

RESULTS

MME inhibited the expression of iNOS and COX-2 at mRNA and protein levels, resulting in reduction of NO and PGE2 production. As a result, pro-inflammatory cytokines were reduced by MME. MME also inhibited the activation and translocation of NF-κB by preventing inhibitor κB-α (IκB-α) degradation. Moreover, MME inhibited the phosphorylation of extracellular signal regulated kinases (ERKs) and c-Jun N-terminal kinases (JNKs). Main anti-inflammatory compound in MME was identified as sargachromenol by NMR spectroscopy.

CONCLUSIONS

These results indicate that the anti-inflammatory effect of sargachromenol-rich MME on LPS-stimulated microglia is mainly regulated by the inhibition of IκB-α/NF-κB and ERK/JNK pathways.