Methanol extract of Osbeckia stellata suppresses lipopolysaccharide- and HCl/ethanol-induced inflammatory responses by inhibiting Src/Syk and IRAK1

Preparation of silver nanoparticles by Osbeckia stellata aqueous extract via green synthesis approach: Characterization and assessment of their antioxidant, antidiabetic, cytotoxicity, and antibacterial properties

Silver nanoparticles (Ag NPs) via green synthesis using medicinal plants have been widely used in natural product research due to the economical and eco-friendly properties of NPs. The plant-derived Ag NPs biosynthesis comprises the interaction between silver nitrate (precursor) and bioactive components of plant extract (reducing agents). In this work, Ag NPs were biosynthesized using Osbeckia stellata leaves aqueous extract. Characterization of Ag NPs was done by using ultraviolet-visible absorption (UV-Vis) spectroscopy, dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray analysis (EDX). Further, antioxidant, antidiabetic, cytotoxicity, and antimicrobial activities were evaluated to establish the pharmacological properties of Ag NPs. UV-Vis spectroscopy and FTIR showed an absorption peak of Ag NPs due to the surface plasmonic resonance. In contrast, the particle size in the nanometer range was analyzed by XRD and DLS. The size of the particle was confirmed by the SEM, TEM, and EDX in the nanometer range. This study showed the spherical shape and crystalline nature of NPs. Zeta potential was used to determine the stability of Ag NPs. Biosynthesized Ag NPs showed significantly potent antioxidant, antidiabetic, and cytotoxicity activity. Ag NPs also showed effectiveness against gram-positive (Escherichia coli) and gram-negative (Staphylococcus aureus) bacteria in the antimicrobial activity study. The result concluded that these Ag NPs might be used in biomedical and pharmacological fields.

Protective effects of a triple-fermented barley extract (FBe) against HCl/EtOH-induced gastric mucosa damage in mice

This study was designed to observe the possible protective effects of a triple-fermented barley (Hordeum vulgare L.) extract (FBe) obtained by saccharification and using Saccharomyces cerevisiae and Weissella cibaria in alleviating gastric damage induced by a hydrochloric acid (HCl) and ethanol (EtOH) mixture in mice. After oral administration of FBe (300, 200, and 100 mg/kg) followed by 1 hr before and after the single treatment of HCl/EtOH (H/E) mixture, the hemorrhagic lesion scores, histopathology of the stomach, gastric nitrate/nitrite content, lipid peroxidation, and antioxidant defense systems including catalase and superoxide dismutase activities were observed. Following a single oral treatment of H/E-induced gastric damages as measured by hemorrhagic gross lesions and histopathological gastric, ulcerative lesions were significantly and dose-dependently (p < 0.01 or p < 0.05) inhibited in mice, when all three different doses of FBe were administered as compared to those in H/E control mice. In particular, FBe also increased gastric nitrate/nitrite content and strengthened the antioxidant defense, with a decrease in the level of gastric lipid peroxidation, but increased the activities of CAT and SOD. Moreover, the effects of FBe are comparable to that of ranitidine, a reference drug. The obtained results suggest that this fermented barley extract prevented mice from H/E-induced gastric mucosal damages through the suppression of inflammatory responses and oxidative stress-responsive free radicals. Thus, FBe can be useful to treat patients suffering from gastric mucosal disorders as a potent food supplement, and thereby, it would increase the necessity of application in the food industry.

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

BACKGROUND AND AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Medicinal plant diversity and traditional healing practices in eastern Nepal

ETHNOPHARMACOLOGICAL RELEVANCE

The rich floral and ethnic composition of eastern Nepal and the widespread utilization of locally available medicinal plants offer remarkable opportunity for ethnomedicinal research. The present paper aims to explore medicinal plant diversity and use in the remote villages of eastern Nepal. It also aims to evaluate ethnopharmacological significance of the documented use reports and identify species of high indigenous priority.

MATERIALS AND METHODS

The study was undertaken in four villages located in the Sankhuwasabha district in eastern Nepal. Ethnomedicinal information was collected through structured interviews. The homogeneity of informant's knowledge and the relative importance of documented medicinal plants were validated by informant consensus factor and use value, respectively. Species preference for treatment of particular diseases was evaluated through fidelity level.

RESULTS

We reported medicinal properties of 48 species belonging to 33 families and 40 genera, for the treatment of 37 human ailments. The uses of 10 medicinal plants were previously undocumented. The informant consensus factor (F_IC) ranged between 0.38 and 1 with about 50% of values greater than 0.80 and over 75% of values greater than 0.70, indicating moderate to high consensus among the informants on the use of medicinal plants in the region. Swertia chirayita was the most preferred species with significantly high use values, followed by Paris polyphylla and Neopicrorhiza scrophulariiflora.

CONCLUSIONS

The remote villages in eastern Nepal possess rich floral and cultural diversity with strong consensus among informants on utilization of plants for local healthcare. The direct pharmacological evidence for medicinal properties of most species indicates high reliability of documented information. Careful and systematic screening of compounds isolated from these plants could possibly provide good opportunity for the discovery of novel medicines to treat life-threatening human diseases. We recommend prioritization of medicinal plants and reinforcement of existing cultivation practices for sustainable management of high-priority species.

The saponin DT-13 attenuates tumor necrosis factor-α-induced vascular inflammation associated with Src/NF-кB/MAPK pathway modulation

This study aimed to explore the effect of DT-13 (25(R,S)-ruscogenin- 1-O- [β-d-glucopyranosyl- (1→2)][β-d-xylopyranosyl-(1→3)]-β -d- fucopyranoside) on tumor necrosis factor (TNF)-α-induced vascular inflammation and the potential molecular mechanisms. In vitro, DT-13 suppressed TNF-α-induced adhesion and migration of human umbilical vein endothelial cells (HUVECs) by inhibiting the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). DT-13 markedly suppressed NF-кB p65 phosphorylation, and when NF-кB p65 was over-expressed, the inhibitory effect of DT-13 on adhesion molecular decreased. DT-13 also suppressed TNF-α induced luciferase activities of ICAM-1 and VCAM-1 promoter containing NF-κB binding sites. Furthermore, DT-13 markedly suppressed p38 phosphorylation and Src degradation induced by TNF-α, whereas had no significant effect on ERK and JNK activation. In vivo, DT-13 at 4 mg/kg prevented vascular inflammation and the expression of adhesion molecules induced by TNF-α in mice. These findings suggest that DT-13 abrogates vascular inflammation by down-regulating adhesion molecules associated with modulating the NF-кB, p38MAPK, Src signaling pathways, and NF-κB binding site is at least one of the targets of DT-13. This study provides novel information regarding the mechanism by which DT-13 exerts its effects on vascular inflammation, which is important for the onset and progression of various diseases.

Anti-inflammatory activities and mechanisms of Artemisia asiatica ethanol extract

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia asiatica Nakai (Compositae) is a representative herbal plant used to treat infection and inflammatory diseases. Although Artemisia asiatica is reported to have immunopharmacological activities, the mechanisms of these activities and the effectiveness of Artemisia asiatica preparations in use are not known.

MATERIALS AND METHODS

To evaluate the anti-inflammatory activities of Artemisia asiatica ethanol extract (Aa-EE), we assayed nitric oxide (NO), tumor necrosis factor (TNF)-α, and prostaglandin E2 (PGE2) in macrophages and measured the extent of tissue injury in a model of gastric ulcer induced in mice by treatment with HCl in EtOH. Putative enzymatic mediators of Aa-EE activities were identified by nuclear fractionation, reporter gene assay, immunoprecipitation, immunoblotting, and kinase assay. Active compound in Aa-EE was identified using HPLC.

RESULTS

Treatment of RAW264.7 cells and peritoneal macrophages with Aa-EE suppressed the production of NO, PGE2, and TNF-α in response to lipopolysaccharide (LPS) and induced heme oxygenase-1 expression. The Aa-EE also ameliorated symptoms of gastric ulcer in HCl/EtOH-treated mice. These effects were associated with the inhibition of nuclear translocation of nuclear factor (NF)-κB and activator protein (AP)-1, implying that the anti-inflammatory action of the Aa-EE occurred through transcriptional inhibition. The upstream regulatory signals Syk and Src for translocation of NF-κB and TRAF6 for AP-1 were identified as targets of this effect. Analysis of Aa-EE by HPLC revealed the presence of luteolin, known to inhibit NO and PGE2 activity.

CONCLUSION

The anti-inflammatory activities attributed to Artemisia asiatica Nakai in traditional medicine may be mediated by luteolin through inhibition of Src/Syk/NF-κB and TRAF6/JNK/AP-1 signaling pathways.

Functional roles of p38 mitogen-activated protein kinase in macrophage-mediated inflammatory responses

Inflammation is a natural host defensive process that is largely regulated by macrophages during the innate immune response. Mitogen-activated protein kinases (MAPKs) are proline-directed serine and threonine protein kinases that regulate many physiological and pathophysiological cell responses. p38 MAPKs are key MAPKs involved in the production of inflammatory mediators, including tumor necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2). p38 MAPK signaling plays an essential role in regulating cellular processes, especially inflammation. In this paper, we summarize the characteristics of p38 signaling in macrophage-mediated inflammation. In addition, we discuss the potential of using inhibitors targeting p38 expression in macrophages to treat inflammatory diseases.

Methanol extract of Evodia lepta displays Syk/Src-targeted anti-inflammatory activity

ETHNOPHARMACOLOGICAL RELEVANCE

Evodia lepta (Spreng.) Merr., in the Rutaceae family, is a medicinal plant traditionally used to treat inflammatory symptoms such as in meningitis and hepatitis. However, no study has systematically investigated its anti-inflammatory activities including its molecular mechanism.

MATERIALS AND METHODS

The effects of a methanol extract from the roots Evodia lepta (El-ME) were evaluated using lipopolysaccharide (LPS)-treated RAW264.7 cells producing nitric oxide (NO) and prostaglandin E2 (PGE2), and an HCl/ethanol-induced mouse gastritis model. Target molecules were identified by analyzing the activation of transcription factors and their upstream kinases.

RESULTS

El-ME reduced the production of NO and PGE2 from LPS-activated RAW264.7 cells in a dose-dependent manner. El-ME also ameliorated the gastritis symptoms of EtOH/HCl-treated mice. The extract suppressed production of mRNA for the inducible NO synthase (iNOS) and cyclooxygenase (COX)-2; the nuclear translocation of nuclear factor (NF)-κB; the phosphorylation of upstream kinases that activate NF-κB; and the kinase activities of Syk and Src.

CONCLUSION

The anti-inflammatory effects of El-ME might be due to its suppression of Syk/Src and NF-κB. Considering the in vitro and in vivo efficacy of El-ME, Evodia lepta could be developed into an anti-inflammatory herbal remedy.

In vitro and in vivo anti-inflammatory effect of Rhodomyrtus tomentosa methanol extract

ETHNOPHARMACOLOGICAL RELEVANCE

Rhodomyrtus tomentosa (Aiton) Hassk. is a representative Thai medicinal plant traditionally used in South Asian countries to relieve various inflammatory symptoms. However, no systematic studies on its anti-inflammatory activity and mechanisms have been reported.

MATERIALS AND METHODS

The effect of the methanol extract from the leaves of this plant (Rt-ME) on the production of inflammatory mediators [nitric oxide (NO) and prostaglandin E2 (PGE2)] and the molecular mechanism of Rt-ME-mediated inhibition, including target enzymes, were studied with RAW264.7, peritoneal macrophage, and HEK293 cells. Additionally, the in vivo anti-inflammatory activity of this extract was evaluated with mouse gastritis and colitis models.

RESULTS

Rt-ME clearly inhibited the production of NO and PGE2 in lipopolysaccharide (LPS)-activated RAW264.7 cells and peritoneal macrophages in a dose-dependent manner. According to RT-PCR, immunoblotting and immunoprecipitation analyses and a kinase assay with mRNA, whole cell extract, and nucleus lysates from RAW264.7 cells and mice, it was revealed that Rt-ME was capable of suppressing the activation of both nuclear factor (NF)-κB and activator protein (AP)-1 pathways by directly targeting Syk/Src and IRAK1/IRAK4.

CONCLUSION

Rt-ME could have anti-inflammatory properties by suppressing Syk/Src/NF-kB and IRAK1/IRAK4/AP-1 pathways and will be further developed as a herbal remedy for preventive and/or curative purposes in various inflammatory diseases.

Methanol extract of Hopea odorata suppresses inflammatory responses via the direct inhibition of multiple kinases

ETHNOPHARMACOLOGICAL RELEVANCE

Hopea odorata Roxb. (Dipterocarpaceae) is a representative Thai ethnopharmacological herbal plant used in the treatment of various inflammation-related diseases. In spite of its traditional use, systematic studies of its anti-inflammatory action have not been performed.

MATERIALS AND METHODS

The inhibitory activities of a Hopea odorata methanol extract (Ho-ME) on the production of nitric oxide (NO), tumour necrosis factor (TNF)-α, and prostaglandin E(2) (PGE(2)) in RAW264.7 cells and peritoneal macrophages were investigated. The effects of Ho-ME on the gastritis symptoms induced by HCl/EtOH and on ear oedemas induced by arachidonic acid were also examined. Furthermore, to identify the immunopharmacological targets of this extract, nuclear fractionation, a reporter gene assay, immunoprecipitation, immunoblot analysis, and a kinase assay were employed.

RESULTS

Ho-ME strongly inhibited the release of NO, PGE(2), and TNF-α in RAW264.7 cells and peritoneal macrophages stimulated by lipopolysaccharide (LPS). Ho-ME also clearly suppressed the gene expression of pro-inflammatory cytokines and chemokines, such as interferon (IFN)-β, interleukin (IL)-12, and monocyte chemotactic protein-1 (MCP-1). By analysing the inhibited target molecules, Syk and Src were found to be suppressed in the inhibition of nuclear factor (NF)-κB pathway. In addition, the observed downregulation of activator protein (AP)-1 and cAMP response element-binding (CREB) was due to the direct inhibition of interleukin-1 receptor-associated kinase (IRAK)1 and IRAK4, which was also linked to the suppression of c-Jun N-terminal kinase (JNK) and p38. In agreement with the in vitro observations, this extract also ameliorated the inflammatory symptoms in EtOH/HCl-induced gastritis and arachidonic acid-induced ear oedemas in mice.

CONCLUSION

Ho-ME has potential as a functional herbal remedy targeting Syk- and Src-mediated anti-inflammatory mechanisms. Future pre-clinical studies will be needed to investigate this possibility.