Eleutherococcus senticosus extract attenuates LPS-induced iNOS expression through the inhibition of Akt and JNK pathways in murine macrophage

Flavanols and Flavanes from Crinum asiaticum and Their Effects on LPS Signaling Pathway Through the Inhibition of NF-κB Activation

Three new flavanols, (2R,3S)-7-methoxy-flavan-3-ol (1: ), (2R,3S)-7-hydroxy-flavan-3-ol (2: ), and (2R,3S)-2'-hydroxy-7-methoxy-flavan-3-ol (3: ), together with two known flavans (4: and 5: ), were isolated from the chloroform extract of Crinum asiaticum. Their structures were elucidated by various spectroscopic methods, including 1D and 2D NMR, HR-ESI-MS, and CD data. The isolated compounds 1: and 3: -5: showed inhibitory activity toward LPS-induced nitric oxide (NO) production. Further investigation of the NF-κB pathway mechanisms indicated that 1: and 3: -5: inhibited the LPS-induced IL-6 production and p65 subunit phosphorylation of NF-κB in RAW264.7 cells, with an effective dose of 10 µM.

Anti-Arthritic and Anti-Inflammatory Potential of Spondias mangifera Extract Fractions: An In Silico, In Vitro and In Vivo Approach

The fruits of Spondias mangifera (S. mangifera) have traditionally been used for the management of rheumatism in the northeast region of India. The present study explores the probable anti-arthritis and anti-inflammatory potential of S. mangifera fruit extract's ethanolic fraction (EtoH-F). To support this study, we first approached the parameters in silico by means of the active constituents of the plant (beta amyrin, beta sitosterol, oleonolic acid and co-crystallised ligands, i.e., SPD-304) via molecular docking on COX-1, COX-2 and TNF-α. Thereafter, the absorption, distribution, metabolism, excretion and toxicity properties were also determined, and finally experimental activity was performed in vitro and in vivo. The in vitro activities of the plant extract fractions were evaluated by means of parameters like 1,1-Diphenyl-2- picrylhydrazyl (DPPH), free radical-reducing potential, albumin denaturation, and protease inhibitory activity. The in vivo activity was evaluated using parameters like COX, TNF-α and IL-6 inhibition assay and arthritis score in Freund Adjuvant (CFA) models at a dose of 400 mg/kg b.w. per day of different fractions (hexane, chloroform, alcoholic). The molecular docking assay was performed on COX-1, COX-2 and TNF-α. The results of in vitro studies showed concentration-dependent reduction in albumin denaturation, protease inhibitors and scavenging activity at 500 µg/mL. Administration of the S. mangifera alcoholic fraction at the abovementioned dose resulted in a significant reduction (p < 0.01) in arthritis score, paw diameters, TNF-α, IL-6 as compared to diseased animals. The docking results showed that residues show a critical binding affinity with TNF-α and act as the TNF-α antagonist. The alcoholic fraction of S. mangifera extract possesses beneficial effects on rheumatoid arthritis as well as anti-inflammatory potential, and can further can be used as a possible agent for novel target-based therapies for the management of arthritis.

A comparative study on root and bark extracts of Eleutherococcus senticosus and their effects on human macrophages

BACKGROUND

Eleutherococcus senticosus or Siberian ginseng is a medicinal plant containing adaptogenic substances believed to regulate immune responses. Both, the root and stem bark are commonly used in traditional medicines.

PURPOSE

The purpose of the present study is to chemically characterize E. senticosus root and bark extracts and to compare their effects on functions of human primary macrophages.

STUDY DESIGN AND METHODS

HPLC-DAD-MS analysis was used to characterize chemical constituents of alcoholic extracts from E. senticosus root and bark. The data obtained and available databases were combined for network pharmacology analysis. Involvement of predicted pathways was further functionally confirmed by using monocyte-derived human macrophages and endotoxin-free E. senticosus root and bark extracts.

RESULTS

Chemical analysis showed that the root extract contained more syringin, caffeic acid, and isofraxidin than the bark extract. At variance, bark extract contained more sesamin and oleanolic acid. Coniferyl aldehyde and afzelin were below the limit of quantification in both extracts. Network pharmacology analysis indicated that constituents of E. senticosus might affect the immune cell phenotype and signaling pathways involved in cell metabolism and cytoskeleton regulation. Indeed, both extracts promoted actin polymerization, migration, and phagocytosis of E. coli by macrophages pointing to macrophage polarization towards the M2 phenotype. In addition, treatment with E. senticosus root and bark extracts decreased phosphorylation of Akt on Ser473 and significantly reduced expression of the hemoglobin scavenger receptor CD163 by macrophages. Neither extract affected expression of CD11b, CD80, or CD64 by macrophages. In addition, macrophages treated with the bark extract, but not with the root extract, exhibited activated p38 MAPK and NF-κB and released increased, but still moderate, amounts of proinflammatory TNF-α and IL-6, anti-inflammatory IL-10, and chemotactic CCL1, which all together point to a M2b-like macrophage polarization. Differently, the root extract increased the IL-4-induced expression of anti-inflammatory CD200R. These changes in monocytes are in agreement with an increased M2a macrophage polarization.

CONCLUSION

The ability of E. senticosus root and bark extracts to promote polarization of human macrophages towards anti-inflammatory M2a and M2b phenotypes, respectively, might underlay the immunoregulatory activities and point to potential wound healing promoting effects of this medicinal plant.

Treatment with Peanut Sprout Root Extract Alleviates Inflammation in a Lipopolysaccharide-Stimulated Mouse Macrophage Cell Line by Inhibiting the MAPK Signaling Pathway

Inflammation is a key response of the immune system to infection but aberrant inflammatory activity can lead to tissue damage and inflammatory diseases. Increasing evidence suggests that peanut sprout root extract (PSRE) has anti-inflammatory activity, and the aim of this study is therefore to investigate the effects of PSRE on the inflammatory response and the molecular mechanisms underpinning this effect in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Using a combination of cell viability, ELISA, and nitric oxide (NO) assays, together with Western blotting, we showed that PSRE effectively inhibited NO production in LPS-stimulated cells and significantly reduced the expression of pro-inflammatory cytokines, including IL-6, IL-1β, and PGE2, at a dose of 200 µg/mL of PSRE, whereas TNF-α expression tended to decrease under PSRE treatment. We also confirmed a dose-dependent and significant inhibition of iNOS and COX-2 protein expression. In addition, PSRE treatment induced anti-inflammatory effects by inhibiting the phosphorylation of MAPKs (ERK, JNK, and p38) and NF-κB activation. Our results indicate that the anti-inflammatory properties of PSRE may result from inhibition of the MAPK pathways, which are known promoters of cytokine secretion.

Novel molecular mechanisms for the adaptogenic effects of herbal extracts on isolated brain cells using systems biology

INTRODUCTION

Adaptogens are natural compounds or plant extracts that increase adaptability and survival of organisms under stress. Adaptogens stimulate cellular and organismal defense systems by activating intracellular and extracellular signaling pathways and expression of stress-activated proteins and neuropeptides. The effects adaptogens on mediators of adaptive stress response and longevity signaling pathways have been reported, but their stress-protective mechanisms are still not fully understood.

AIM OF THE STUDY

The aim of this study was to identify key molecular mechanisms of adaptogenic plants traditionally used to treat stress and aging-related disorders, i.e., Rhodiola rosea, Eleutherococcus senticosus, Withania somnifera, Rhaponticum carthamoides, and Bryonia alba.

MATERIALS AND METHODS

To investigate the underlying molecular mechanisms of adaptogens, we conducted RNA sequencing to profile gene expression alterations in T98G neuroglia cells upon treatment of adaptogens and analyzed the relevance of deregulated genes to adaptive stress-response signaling pathways using in silico pathway analysis software.

RESULTS AND DISCUSSION

At least 88 of the 3516 genes regulated by adaptogens were closely associated with adaptive stress response and adaptive stress-response signaling pathways (ASRSPs), including neuronal signaling related to corticotropin-releasing hormone, cAMP-mediated, protein kinase A, and CREB; pathways related to signaling involving CXCR4, melatonin, nitric oxide synthase, GP6, Gαs, MAPK, neuroinflammation, neuropathic pain, opioids, renin-angiotensin, AMPK, calcium, and synapses; and pathways associated with dendritic cell maturation and G-coupled protein receptor-mediated nutrient sensing in enteroendocrine cells. All samples tested showed significant effects on the expression of genes encoding neurohormones CRH, GNRH, UCN, G-protein-coupled and other transmembrane receptors TLR9, PRLR, CHRNE, GP1BA, PLXNA4, a ligand-dependent nuclear receptor RORA, transmembrane channels, transcription regulators FOS, FOXO6, SCX, STAT5A, ZFPM2, ZNF396, ZNF467, protein kinases MAPK10, MAPK13, MERTK, FLT1, PRKCH, ROS1, TTN), phosphatases PTPRD, PTPRR, peptidases, metabolic enzymes, a chaperone (HSPA6), and other proteins, all of which modulate numerous life processes, playing key roles in several canonical pathways involved in defense response and regulation of homeostasis in organisms. It is for the first time we report that the molecular mechanism of actions of melatonin and plant adaptogens are alike, all adaptogens tested activated the melatonin signaling pathway by acting through two G-protein-coupled membrane receptors MT1 and MT2 and upregulation of the ligand-specific nuclear receptor RORA, which plays a role in intellectual disability, neurological disorders, retinopathy, hypertension, dyslipidemia, and cancer, which are common in aging. Furthermore, melatonin activated adaptive signaling pathways and upregulated expression of UCN, GNRH1, TLR9, GP1BA, PLXNA4, CHRM4, GPR19, VIPR2, RORA, STAT5A, ZFPM2, ZNF396, FLT1, MAPK10, MERTK, PRKCH, and TTN, which were commonly regulated by all adaptogens tested. We conclude that melatonin is an adaptation hormone playing an important role in regulation of homeostasis. Adaptogens presumably worked as eustressors ("stress-vaccines") to activate the cellular adaptive system by inducing the expression of ASRSPs, which then reciprocally protected cells from damage caused by distress. Functional investigation by interactive pathways analysis demonstrated that adaptogens activated ASRSPs associated with stress-induced and aging-related disorders such as chronic inflammation, cardiovascular health, neurodegenerative cognitive impairment, metabolic disorders, and cancer.

CONCLUSION

This study has elucidated the genome-wide effects of several adaptogenic herbal extracts in brain cells culture. These data highlight the consistent activation of ASRSPs by adaptogens in T98G neuroglia cells. The extracts affected many genes playing key roles in modulation of adaptive homeostasis, indicating their ability to modify gene expression to prevent stress-induced and aging-related disorders. Overall, this study provides a comprehensive look at the molecular mechanisms by which adaptogens exerts stress-protective effects.

Anti-inflammatory effect of the extracts from the branch of Taxillus yadoriki being parasitic in Neolitsea sericea in LPS-stimulated RAW264.7 cells

Mistletoe has been used as the herbal medicine to treat hypertension, diabetes mellitus, inflammation, arthritis and viral infection. In this study, we evaluated the anti-inflammatory effect of extracts of branch from Taxillus yadoriki being parasitic in Neolitsea sericea (TY-NS-B) using in vitro model. TY-NS-B significantly inhibited LPS-induced secretion of NO and PGE₂ in RAW264.7 cells. TY-NS-B was also observed to inhibit LPS-mediated iNOS COX-2 expression. In addition, TY-NS-B attenuated production of inflammatory cytokines such as TNF-α and IL-1β induced by LPS. TY-NS-B blocked LPS-mediated inhibitor of IκB-α, and inhibited p65 translocation to the nucleus and NF-κB activation. Furthermore, TY-NS-B reduced the phosphorylation of MAPKs such as p38 and JNK, but not ERK1/2. In addition, TY-NS-B increased ATF3 expression and ATF3 knockdown by ATF3 siRNA attenuated TY-NS-B-mediated inhibition of pro-inflammatory mediator expression. Collectively, our results suggest that TY-NS-B exerts potential anti-inflammatory effects by suppressing NF-κB and MAPK signaling activation, and increasing ATF3 expression. These findings indicate that TY-NS-B could be further developed as an anti-inflammatory drug.

Anti-inflammatory sesquiterpenoids from the Traditional Chinese Medicine Salvia plebeia: Regulates pro-inflammatory mediators through inhibition of NF-κB and Erk1/2 signaling pathways in LPS-induced Raw264.7 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Salvia plebeia R. Brown, a traditional Chinese medicinal herb, has been used to treat inflammatory diseases such as cough, hepatitis, and diarrhea for a long history.

AIM OF THE STUDY

The aim of the present study was to isolate and identify potential anti-inflammatory agents from the herb of S. plebeia, which may have contributed to its folk pharmacological use in the treatment of inflammatory diseases.

MATERIAL AND METHODS

The aerial parts of S. plebeia were extracted with 95% ethanol and separated by silica gel, RP-C₁₈, Sephadex LH-20, and HPLC. The structures of the isolated compounds were elucidated by extensive spectroscopic analysis (MS, NMR, and X-ray). Anti-inflammatory activities of all compounds were evaluated by the model of LPS-induced up-regulated of NO in Raw264.7 macrophages. The expression levels of cytokine (TNF-α) and proteins (iNOS and COX-2) were assessed by ELISA kit and Western blotting analysis, respectively. Furthermore, the influences of salviplenoid A (1) on NF-κB and MAPK signaling pathways were determined by Western blotting analysis and immunofluorescence assay.

RESULTS

Six new (1-6, salviplenoids A-F) and ten known (7-16) sesquiterpenoids were isolated from the herb of S. plebeia. The absolute configurations of compounds 1, 2, and 7 were determined by X-ray diffraction. The new eudesmane-type sesquiterpenoid, salviplenoid A (1), significantly decreased the release of NO and TNF-α and the expression of proteins iNOS and COX-2. In addition, the biochemical mechanistic study indicated that 1 regulated the NF-κB dependent transcriptional activity through inhibiting the nuclear translocation of p50/p65 dimer and decreasing the phosphorylation of IκB and Erk1/2.

CONCLUSIONS

Among all sesquiterpenoids isolated from S. plebeian, the new salviplenoid A (1) exhibited the most potent anti-inflammatory activity in LPS-induced Raw264.7 cells via inhibition of NF-κB and Erk1/2 signaling pathways.

Anti-inflammatory effect of the extract from fermented Asterina pectinifera with Cordyceps militaris mycelia in LPS-induced RAW264.7 macrophages

In our previous work, Asterina pectinifera was fermented with Cordyceps militaris mycelia to improve its bioactivities and was reported to have strong antioxidant activities. The aim of the current study was to investigate its anti-inflammatory effect and mechanisms of action. In this study, we observed the inhibitory effect of the extract from fermented A. pectinifera with C. militaris mycelia (FACM) on nitric oxide (NO) production and its molecular mechanism in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. FACM could decrease LPS-induced NO production. Western blot analysis showed that FACM could down-regulate LPS-induced expression of inducible NO synthase without affecting cyclooxygenase-2. Moreover, FACM exhibited anti-inflammatory activity in LPS-induced RAW264.7 mouse macrophage cells through proinflammatory mediators including TNF-α and IL-6 via nuclear factor kappa B pathway. FACM inhibited LPS-induced phosphorylation of extracellular-signal-regulated kinase expression. Our results suggest that FACM may be a potential candidate for inflammation therapy by attenuating the generation of cytokines, production of NO, and generation of ROS in RAW264.7 cells.

A novel translocator protein 18 kDa ligand, ZBD-2, exerts neuroprotective effects against acute spinal cord injury

Traumatic spinal cord injury (SCI) happens accidently and often leads to motor dysfunction due to a series of biochemical and pathological events and damage, either temporarily or permanently. Translocator protein 18 (TSPO) has been found to be involved in the synthesis of endogenous neurosteroids which have multiple effects on neurons, but the internal mechanisms are not clear. N-benzyl-N-ethyl-2-(7,8-oxo-2-phenyl-9H-purin-9-yl) acetamide (ZBD-2), a newly reported ligand of TSPO, shows some neuroprotective effect against focal cerebral ischemia in vivo and NMDA-induced neurotoxicity in vitro. The present study aims to examine the role of ZBD-2 in SCI mice and elucidate the underlying molecular mechanisms. The SCI model was established by crushing spinal cord. ZBD-2 (10 mg/kg) significantly enhanced the hindlimb locomotor functions after SCI and decreased the tissue damage and conserved the white matter of the spinal cord. High-dose ZBD-2 alleviated the oxidative stress induced by SCI and regulated the imbalance between NR2B-containing NMDA and GABA receptors by increasing the levels of GAD67 in the spinal cord of SCI mice. Additionally, ZBD-2 (10 mg/kg) increased phosphorylated Akt (p-Akt) and decreased the ratio of Bax/Bcl-2. These results demonstrate that ZBD-2 performs neuroprotection against SCI through regulating the synaptic transmission and the PI3K/AKT signaling pathway.

Regulatory effects and molecular mechanism of Trigonostemon reidioides on lipopolysaccharide‑induced inflammatory responses in RAW264.7 cells

Trigonostemon reidioides (Kurz) Craib has been traditionally used for the treatment of vomiting and asthma in Cambodia. However, the underlying molecular mechanisms of the anti‑inflammatory effect of T. reidioides extract remains unknown. The present study investigated the anti‑inflammatory activity and molecular action of an ethanol extract of T. reidioides (ETR) in lipopolysaccharide (LPS)‑induced RAW264.7 macrophage cells. Nitric oxide assays, ELISA, reverse transcription‑quantitative polymerase chain reaction and western blot analysis were used. ETR treatment inhibited the production of nitric oxide by downregulating inducible nitric oxide synthase expression, while exhibiting no significant cytotoxicity compared with macrophages treated with LPS‑alone. Consequently, ETR decreased the production of certain proinflammatory cytokines, including interleukin (IL)‑1β, IL‑6 and tumor necrosis factor‑α. Additionally, ETR inhibited the activation of mitogen‑activated protein kinases (MAPKs), including extracellular signal‑regulated kinase, c‑Jun N‑terminal kinase and p38 MAPK, as well as the phosphatidylinositol 3‑kinase (PI3K)/Akt signaling pathway. These effects were mediated by inhibition of the nuclear localization of nuclear factor κ‑B (NF‑κB). Taken together, the results of the present study demonstrate that ETR may exert an anti‑inflammatory effect by inhibiting the expression of inflammatory mediators and cytokines via downregulation of the NF‑κB, PI3K/Akt and the MAPK signaling pathways in LPS‑stimulated macrophages. Based on these results, we hypothesize that ETR may be a potential therapeutic agent for the treatment of inflammatory disorders.

Bystander signaling via oxidative metabolism

The radiation-induced bystander effect (RIBE) is the initiation of biological end points in cells (bystander cells) that are not directly traversed by an incident-radiation track, but are in close proximity to cells that are receiving the radiation. RIBE has been indicted of causing DNA damage via oxidative stress, besides causing direct damage, inducing tumorigenesis, producing micronuclei, and causing apoptosis. RIBE is regulated by signaling proteins that are either endogenous or secreted by cells as a means of communication between cells, and can activate intracellular or intercellular oxidative metabolism that can further trigger signaling pathways of inflammation. Bystander signals can pass through gap junctions in attached cell lines, while the suspended cell lines transmit these signals via hormones and soluble proteins. This review provides the background information on how reactive oxygen species (ROS) act as bystander signals. Although ROS have a very short half-life and have a nanometer-scale sphere of influence, the wide variety of ROS produced via various sources can exert a cumulative effect, not only in forming DNA adducts but also setting up signaling pathways of inflammation, apoptosis, cell-cycle arrest, aging, and even tumorigenesis. This review outlines the sources of the bystander effect linked to ROS in a cell, and provides methods of investigation for researchers who would like to pursue this field of science.

Upregulation of HO-1 Attenuates LPS-Stimulated Proinflammatory Responses Through Downregulation of p38 Signaling Pathways in Rat Ovary

Heme oxygenase-1 (HO-1) plays a key role in the regulation of the inflammatory response. However, the specific mechanism underlying the anti-inflammatory role of HO-1 in the reproductive system is unclear. The aim of this study was to evaluate the role of the mechanism of HO-1 in the regulation of the inflammatory response stimulated by lipopolysaccharide (LPS) in rat ovary. LPS-stimulated inflammatory models were established. Rats were pretreated with HO-1 activator (hemin) or inhibitor (ZnPP) before LPS stimulation, and we evaluated the expression of HO-1 by real-time PCR and Western blot. The messenger RNA (mRNA) expression and secretion of IL-1β and IL-6 in rat ovary were analyzed using real-time PCR and ELISA. In addition, we also analyzed the p38 and p-p38 protein expression in the ovary. Our results demonstrate that HO-1 is an anti-inflammatory factor in LPS-stimulated ovary, which regulates the inflammatory response through downregulation of p38 signaling pathways in rat ovary.

Reactive nitrogen species in cellular signaling

The transduction of cellular signals occurs through the modification of target molecules. Most of these modifications are transitory, thus the signal transduction pathways can be tightly regulated. Reactive nitrogen species are a group of compounds with different properties and reactivity. Some reactive nitrogen species are highly reactive and their interaction with macromolecules can lead to permanent modifications, which suggested they were lacking the specificity needed to participate in cell signaling events. However, the perception of reactive nitrogen species as oxidizers of macromolecules leading to general oxidative damage has recently evolved. The concept of redox signaling is now well established for a number of reactive oxygen and nitrogen species. In this context, the post-translational modifications introduced by reactive nitrogen species can be very specific and are active participants in signal transduction pathways. This review addresses the role of these oxidative modifications in the regulation of cell signaling events.

Development of bacoside enriched date syrup juice and its evaluation for physical endurance

Bacoside rich juice (BRJ) was developed using date syrup as base. BRJ was evaluated for physicochemical, sensory attributes and its effect on physical endurance. Overall acceptability of BRJ and date syrup juice (DSJ) was good according to hedonic scale/ratings. Twenty four adult male Wistar rats were divided into 4 groups (n = 6). Sedentary (Group I) and control (Group II) group rats were allowed to drink water whereas DSJ and BRJ group rats were provided free access to drink DSJ (Group III) and BRJ (Group IV) for 14 days and were subjected to weight-loaded forced swim test (WFST) for every alternate day in order to evaluate the physical endurance. Both BRJ and DSJ group rats swimming efficiency was improved by 3 and 2 folds respectively in comparison with control group on day- 15. Improved physical endurance in BRJ group is due to reduced malondialdehyde levels in brain, liver and muscle tissues by 16.50 %, 17.88 % and 30.20 %, respectively, compared to DSJ group (p < 0.01). In addition, administration of BRJ significantly protected the hepatic and muscle glycogen levels and reduced the levels of lactic acid in comparison to DSJ group. Hence, the present study clearly indicates that BRJ is an effective anti-fatigue drink ameliorates the various impairments associated with physical endurance.

Sulfated chitosan oligosaccharides suppress LPS-induced NO production via JNK and NF-κB inactivation

Various biological effects have been reported for sulfated chitosan oligosaccharides, but the molecular mechanisms of action of their anti-inflammatory effects are still unknown. This study aimed to evaluate the anti-inflammatory effects of sulfated chitosan oligosaccharides and to elucidate the possible mechanisms of action. The results showed that pretreated low molecular weight sulfated chitosan oligosaccharides inhibited the production of nitric oxide (NO) and inflammatory cytokines such as IL-6 and TNF-α in lipopolysaccharide (LPS)-activated RAW264.7 cells. The sulfated chitosan oligosaccharides also suppressed inducible nitric oxide synthase (iNOS), phosphorylation of JNK and translocation of p65, a subunit of NF-κB, into the nucleus by inhibiting degradation of IκB-α. Our investigation suggests sulfated chitosan oligosaccharides inhibit IL-6/TNF-α in LPS-induced macrophages, regulated by mitogen-activated protein kinases (MAPKs) pathways dependent on NF-κB activation.

Effect of plant extracts on H2O2-induced inflammatory gene expression in macrophages

Background

Arctium lappa (AL), Camellia sinensis (CS), Echinacea angustifolia, Eleutherococcus senticosus, Panax ginseng (PG), and Vaccinium myrtillus (VM) are plants traditionally used in many herbal formulations for the treatment of various conditions. Although they are well known and already studied for their anti-inflammatory properties, their effects on H₂O₂-stimulated macrophages are a novel area of study.

Materials and methods

Cell viability was tested after treatment with increasing doses of H₂O₂ and/or plant extracts at different times of incubation to identify the optimal experimental conditions. The messenger (m)RNA expression of TNFα, COX2, IL1β, NFκB1, NFκB2, NOS2, NFE2L2, and PPARγ was analyzed in macrophages under H₂O₂ stimulation. The same genes were also quantified after plant extract treatment on cells pre-stimulated with H₂O₂.

Results

A noncytotoxic dose (200 μM) of H₂O₂ induced active mRNA expression of COX2, IL1β, NFE2L2, NFκB1, NFκB2, NOS2, and TNFα, while PPARγ was depressed. The expression of all genes tested was significantly (P<0.001) regulated by plant extracts after pre-stimulation with H₂O₂. COX2 was downregulated by AL, PG, and VM. All extracts depressed IL1β expression, but upregulated NFE2L2. NFκB1, NFκB2, and TNFα were downregulated by AL, CS, PG, and VM. NOS2 was inhibited by CS, PG, and VM. PPARγ was decreased only after treatment with E. angustifolia and E. senticosus.

Conclusion

The results of the present study indicate that the stimulation of H₂O₂ on RAW267.4 cells induced the transcription of proinflammatory mediators, showing that this could be an applicable system by which to activate macrophages. Plant extracts from AL, CS, PG, and VM possess in vitro anti-inflammatory activity on H₂O₂-stimulated macrophages by modulating key inflammation mediators. Further in vitro and in vivo investigation into molecular mechanisms modulated by herbal extracts should be undertaken to shed light on the development of novel modulating therapeutic strategies.

Anti-inflammatory effects of extract from Haliotis discus hannai fermented with Cordyceps militaris mycelia in RAW264.7 macrophages through TRIF-dependent signaling pathway

In this study, Haliotis discus hannai (H. discus hannai) fermentation was attempted with Cordyceps militaris (C. militaris) mycelia using a solid culture. We tried to ferment H. discus hannai to determine the optimal conditions fermentation with regards to its anti-inflammatory effects. The extracts of H. discus hannai fermented with C. militaris mycelia (HFCM-5) showed higher nitric oxide inhibitory effects than H. discus hannai and C. militaris alone. HFCM-5 also decreased pro-inflammatory cytokines, TNF-α and IL-6 in a dose-dependent manner. HFCM-5 did not affect the MyD88-dependent pathway, but decreased phosphorylation of IRF3 and STAT1 which are involved in TRIF-dependent pathway. Taken together, our results suggest that HFCM-5 exerts its anti-inflammatory effects via TRIF signaling pathway and could potentially be used as a functional food in the regulation of inflammation.

The expression of iNOS and nitrotyrosine in colitis and colon cancer in humans

Chronic inflammation increases the risk of development of several types of malignancies including colon cancer. It also represents a paradigm for the connection between inflammation and cancer in terms of epidemiology and mechanistic studies in preclinical models. A key component of inflammation promoting cancer is the transcription factor NF-κB, which is known to play a critical role in the regulation of the inducible nitric oxide synthase (iNOS) gene. iNOS is an enzyme dominantly expressed during inflammatory reactions. Although synthesis of high amounts of nitric oxide (NO) by iNOS has been demonstrated in pathophysiological processes, such as acute or chronic inflammation and tumorigenesis, the role of iNOS activity in these diseases is still not well understood. Analysis of human biopsies of colitis and colon cancer using immunohistochemistry revealed elevated iNOS protein expression levels, which were strongly paralleled by increased expression of nitrotyrosine suggesting that iNOS has been highly activated in these tissues. These results were corroborated in an in vitro study showing the presence of high iNOS levels in a colon cancer cell line (HT-29) following inflammatory stimuli (TNF-α, peroxynitrite). In addition, the involvement of metastatic processes in the colon biopsies was assessed by means of in situ zymography of MMP activation. MMP 2 (gelatinase A) activation was higher in histopathological sections of colitis and cancer compared to controls. Overall, these data strengthen the findings that in inflammation and colon cancer in humans, iNOS expression and tyrosine nitration may be an indicator of cancer development and progression.

8-(Tosylamino)quinoline inhibits macrophage-mediated inflammation by suppressing NF-κB signaling

AIM

The macrophage-mediated inflammatory response may contribute to the development of cancer, diabetes, atherosclerosis and septic shock. This study was to characterize several new compounds to suppress macrophage-mediated inflammation.

METHODS

Peritoneal macrophages from C57BL/6 male mice and RAW264.7 cells were examined. Anti-inflammatory activity was evaluated in the cells exposed to lipopolysaccharide (LPS). The mechanisms of the anti-inflammatory activity were investigated via measuring transcription factor activation in response to specific signals and via assaying the activities of the target kinases.

RESULTS

Of 7 candidate compounds tested, 8-(tosylamino)quinoline (8-TQ, compound 7) exhibited the strongest activities in suppressing the production of NO, TNF-α, and PGE(2) in LPS-activated RAW264.7 cells and peritoneal macrophages (the IC(50) values=1-5 μmol/L). This compound (1.25-20 μmol/L) dose-dependently suppressed the expression of the pro-inflammatory genes for iNOS, COX-2, TNF-α, and the cytokines IL-1β and IL-6 at the level of transcription in LPS-activated RAW264.7 cells. 8-TQ (20 μmol/L) significantly suppressed the activation of NF-κB and its upstream signaling elements, including inhibitor of κB (IκBα), IκBα kinase (IKK) and Akt in LPS-activated RAW264.7 cells. In in vivo experiments, oral administration of 20 and 40 mg/kg 8-TQ for 3 d significantly alleviated the signs of LPS-induced hepatitis and HCl/EtOH-induced gastritis, respectively, in ICR mice.

CONCLUSION

8-TQ (compound 7) exerts significant anti-inflammatory activity through the inhibition of the Akt/NF-κB pathway, thus may be developed as a novel anti-inflammatory drug.

The effects of propolis and its isolated compounds on cytokine production by murine macrophages

Since propolis and phenolic compounds, such as cinnamic and coumaric acids, have several biological properties, their immunomodulatory effect on cytokine production (IL-1β, IL-6 and IL-10) was investigated. Peritoneal macrophages from BALB/c mice were incubated with propolis, coumaric and cinnamic acids in different concentrations and the concentrations that inhibited cytokine production were tested before or after macrophage challenge with LPS, to evaluate a possible immunomodulatory action. Propolis and the acids stimulated IL-1β production, while IL-6 production was significantly inhibited after incubation with propolis (5, 50 and 100 µg/well), coumaric and cinnamic acids (50 and 100 µg/well). In LPS-challenge protocols, inhibitory concentrations of cinnamic and coumaric acids after LPS incubation prevented efficiently its effects on IL-6 production, whereas propolis inhibited LPS effects both before and after its addition. Propolis, coumaric and cinnamic acids (50 and 100 µg/well) inhibited IL-10 production as well. Both acids showed a similar inhibitory activity on IL-10 production when added after LPS challenge, while propolis counteracted LPS action when added before and after LPS incubation. Propolis modulated the immune/inflammatory response, depending on the concentration. Its efficiency may occur due to the synergistic effect of its compounds, and cinnamic and coumaric acids may be involved in the action of propolis on cytokine production.

A Herbal Composition of Scutellaria baicalensis and Eleutherococcus senticosus Shows Potent Anti-Inflammatory Effects in an Ex Vivo Human Mucosal Tissue Model

Background. Patients seek an effective alternative to pharmacotherapy including herbal treatment options for allergic rhinitis and rhinosinusitis. Material and Methods. Nasal mucosal tissue was obtained from 12 patients, fragmented, preincubated with tissue culture medium, S. baicalensis and/or E. senticosus and/or vitamin C (each compound 0.2 μg/mL and 2 μg/mL) for 1 hour at 37°C/5% CO2, and stimulated with anti-IgE for 30 minutes and 6 hours to imitate the allergic early and late phases. Furthermore, Staphylococcus aureus superantigen B (SEB) stimulation for 6 hours was used to imitate T-cell activation. Results. The combination of S. baicalensis and E. senticosus had a more potent suppressive effect on the release of PGD2, histamine, and IL-5 than S. baicalensis alone. The combination also resulted in a significant inhibition of SEB-induced cytokines comparable or superior to an established topical corticosteroid, fluticasone propionate. Vitamin C increased ciliary beat frequency, but had no anti-inflammatory effects. Discussion. The combination of S. baicalensis and E. senticosus may be able to significantly block allergic early-and late-phase mediators and substantially suppress the release of proinflammatory, and Th1-, Th2-, and Th17-derived cytokines.

Anti-fatigue activity of extracts of stem bark from Acanthopanax senticosus

In the present study, we investigated the anti-fatigue activity in male Kunming mice of extracts of stem bark from Acanthopanax senticosus (ASSE) using a forced swimming test. Mice were divided into four groups (three ASSE administered groups and the control group). The control group were gavaged with distilled water and ASSE administered groups were gavaged with ASSE (100, 200 and 400 mg/kg). After four weeks, a forced swimming test was performed and the biochemical parameters related to fatigue were examined. The results suggested that ASSE could extend the swimming time to exhaustion of the mice, as well as increase the tissue glycogen contents, while decreasing the blood lactate and serum urea nitrogen contents. This indicated that ASSE had anti-fatigue activity and could elevate the exercise tolerance.

Up-regulation of heme oxygenase-1 expression through CaMKII-ERK1/2-Nrf2 signaling mediates the anti-inflammatory effect of bisdemethoxycurcumin in LPS-stimulated macrophages

We have identified a novel anti-inflammatory signaling pathway that leads to the expression of heme oxygenase-1 (HO-1) in response to bisdemethoxycurcumin (BDMC), an analog of curcumin. Treatment with BDMC suppressed inducible nitric oxide synthase expression and nitric oxide (NO) production by down-regulating NF-kappaB activity in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. These effects were reversed by blocking HO-1 activity or expression. The signaling pathway involved in BDMC-mediated HO-1 induction included Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and extracellular signal-regulated kinase 1/2 (ERK1/2). BDMC induced phosphorylation of ERK1/2 in a CaMKII-dependent manner. Pretreatment with the mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor, U0126, inhibited CaMKII-induced stimulation of HO-1 promoter activity, suggesting that ERK1/2 is a downstream mediator of CaMKII in BDMC signaling to HO-1 expression. Furthermore, the CaMKII-ERK1/2 cascade targets the transcription factor, NF-E2-related factor-2 (Nrf2). Finally, inhibition of the Ca(2+)-CaMKII-ERK1/2-linked cascade attenuated significantly suppression by BDMC of LPS-induced iNOS expression and subsequent NO production. Collectively, our findings identify a Ca(2+)/calmodulin-CaMKII-ERK1/2-Nrf2 cascade as a novel anti-inflammatory pathway mediating BDMC signaling to HO-1 expression in macrophages.

Inhibition of TNFα-induced iNOS expression in HSV-tk transduced 9L glioblastoma cell lines by Marasmius oreades substances through NF-κB- and MAPK-dependent mechanisms

Nitric oxide (NO) is a gaseous, radical molecule that plays a role in various physiological processes. Previously, we reported that transduction of murine colon cancer cells (MC38) with herpes simplex virus thymidine kinase (HSV-tk) gene resulted in a significant over-expression of cyclooxygenase-2 (COX-2) and activation of NF-kB pathway. In this study we show that TNFα, but not LPS, was significantly able to stimulate the production of NO in HSV-tk transduced 9L glioblastoma cell lines, mediated by the up-regulation of iNOS transcript and iNOS protein. The TNFα-induced up-regulation of iNOS expression was mediated by MAPK and NF-κB signaling pathways as revealed by using selective pharmaceutical inhibitors. A culture liquid extract of the edible and medicinal mushroom Marasmius oreades that was previously shown to inhibit iNOS expression in MCF-7 was utilized to prepare fractions and evaluate their ability to affect TNFα-induced iNOS expression in HSV tk transduced 9L cell lines. While most of the tested fractions were shown to inhibit TNFα-induced iNOS expression, they targeted different signaling pathways in a selective fashion. Here, we report that fraction SiSiF1 interfered with IKBα phosphorylation and consequently interfered with NF-κB activation pathway. SiSiF1 showed minimal interference with the phosphorylation of p38 and JNK proteins. In contrast, fraction SiSiF3 selectively inhibited the phosphorylation of p38 and fractions SiSiF4 and SiSiF5 selectively inhibited the phosphorylation of JNK with no observed effect against IKBα and p38 phosphorylation. Our data illustrate the complexity of iNOS regulation in HSV tk transduced 9L cell lines and also the richness of natural products with bioactive substances that may act synergistically through different signaling pathways to affect iNOS gene expression.

Anti-inflammatory activities of extracts of Thai spices and herbs with lipopolysaccharide-activated RAW 264.7 murine macrophages

Nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) play important roles in inflammatory processes. This study examined whether 13 spices/herbs commonly used in Thai dishes modulate the production of NO and TNF-alpha by the RAW 264.7 mouse macrophage cell line pretreated with plant extracts (1-100 microg/mL) prior to activation by bacterial lipopolysaccharide (LPS). Tested plant tissues were extracted with ethanol with the exception of roselle, which was extracted with 70% acetone. Eight of the 13 plant extracts inhibited NO and TNF-alpha production in a dose-dependent manner without exerting cytotoxicity. Extract from Limnophila aromatica (Kyeng) was the most robust suppressor of NO production, followed by dill, kaffer lime, chili, Teaw, mint, sweet basil, and pea eggplant, respectively (range of 50% inhibitory concentration [IC(50)] = 11.4-74.6 microg/mL). Kyeng also exhibited the greatest inhibition of TNF-alpha production (IC(50) = 10.5 microg/mL). IC(50) values for NO and TNF-alpha production in LPS-activated RAW 264.7 cells for these extracts were highly correlated (r = 0.772, P = .025). These results suggest that extracts from some spices/herbs in the habitual Thai diet possess anti-inflammatory activity. Moreover, the results support the use of NO production in LPS-activated RAW 264.7 cells as a rapid and cost-effective tool for screening the anti-inflammatory activity of extracts of spices/herbs.

Epigallocatechin-3-gallate (EGCG) attenuates inflammation in MRL/lpr mouse mesangial cells

Epigallocatechin-3-gallate (EGCG), a bioactive component of green tea, has been reported to exert anti-inflammatory effects on immune cells. EGCG is also shown to activate the metabolic regulator, adenosine 5'-monophosphate-activated protein kinase (AMPK). Reports have also indicated that EGCG inhibits the immune-stimulated phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway. The PI3K/Akt/mTOR pathway has been implicated in mesangial cell activation in lupus. Mesangial cells from MRL/lpr lupus-like mice are hyper-responsive to immune stimulation and overproduce nitric oxide (NO) and other inflammatory mediators when stimulated. In our current studies, we sought to determine the mechanism by which EGCG attenuates immune-induced expression of pro-inflammatory mediators. Cultured mesangial cells from MRL/lpr mice were pre-treated with various concentrations of EGCG and stimulated with lipopolysaccharide (LPS)/interferon (IFN)-gamma. EGCG activated AMPK and blocked LPS/IFN-gamma-induced inflammatory mediator production (iNOS expression, supernatant NO and interleukin-6). Interestingly, EGCG attenuated inflammation during AMPK inhibition indicating that the anti-inflammatory effect of EGCG may be partially independent of AMPK activation. Furthermore, we found that EGCG effectively inhibited the immune-stimulated PI3K/Akt/mTOR pathway independently of AMPK, by decreasing phosphorylation of Akt, suggesting an alternate mechanism for EGCG-mediated anti-inflammatory action in mesangial cells. Taken together, these studies show that EGCG attenuated inflammation in MRL/lpr mouse mesangial cells via the PI3K/Akt/mTOR pathway. Our findings suggest a potential therapeutic role for the use of EGCG to regulate inflammation and control autoimmune disease.

Effects of Adaptogens on the Central Nervous System and the Molecular Mechanisms Associated with Their Stress-Protective Activity

Adaptogens were initially defined as substances that enhance the "state of nonspecific resistance" in stress, a physiological condition that is linked with various disorders of the neuroendocrine-immune system. Studies on animals and isolated neuronal cells have revealed that adaptogens exhibit neuroprotective, anti-fatigue, antidepressive, anxiolytic, nootropic and CNS stimulating activity. In addition, a number of clinical trials demonstrate that adaptogens exert an anti-fatigue effect that increases mental work capacity against a background of stress and fatigue, particularly in tolerance to mental exhaustion and enhanced attention. Indeed, recent pharmacological studies of a number of adaptogens have provided a rationale for these effects also at the molecular level. It was discovered that the stress-protective activity of adaptogens was associated with regulation of homeostasis via several mechanisms of action, which was linked with the hypothalamic-pituitary-adrenal axis and the regulation of key mediators of stress response, such as molecular chaperons (e.g., HSP70), stress-activated c-Jun N-terminal protein kinase 1 (JNK1), Forkhead box O (FOXO) transcription factor DAF-16, cortisol and nitric oxide.

Anti-inflammatory effects of Scutellaria baicalensis water extract on LPS-activated RAW 264.7 macrophages

AIM OF THE STUDY

The root of Scutellaria baicalensis Georgi (Labiatae), also known as Scutellariae Radix, possesses anticancer, antiviral, and anti-inflammatory properties. And it is one of the most widespread herbal remedies used in Oriental medicine. In the present study, we investigated the effects of Scutellariae Radix water extract (SR) on proinflammatory mediators secreted from lipopolysaccharide (LPS)-induced RAW 264.7 macrophages.

MATERIAL AND METHODS

Cell viability was assessed by MTT assay and nitric oxide (NO) concentration in the cultured medium was determined by the Griess reaction. Various Cytokines released from LPS-induced Raw 264.7 cells were measured in the cell culture supernatants using a multiplex bead array assay based on xMAP technology.

RESULTS

We found that SR significantly inhibited the production of NO, interleukin (IL)-3, IL-6, IL-10, IL-12p40, IL-17, interferon-inducible protein (IP)-10, keratinocyte-derived chemokine (KC), and vascular endothelial growth factor (VEGF) in LPS-induced RAW 264.7 cells at the concentrations of 25, 50, 100, 200 microg/ml (p<0.05).

CONCLUSIONS

These results suggest that SR has anti-inflammatory activity related with its inhibition of NO, cytokine, chemokine, and growth factor production in macrophages.