Bletilla striata polysaccharides ameliorates lipopolysaccharide-induced injury in intestinal epithelial cells

Bletilla oligosaccharides improved 5-fluorouracil-induced intestinal mucositis in mice by activating NF-κB signalling pathway and regulating intestinal microbiota

Introduction

The Bletilla oligosaccharides (BO) are active compounds extracted from Bletilla striata and have the strong protective effect on the gastrointestinal tract. Chemotherapeutic intestinal mucositis (CIM) is one of the toxic side effects of chemotherapeutic agents on the gastrointestinal tract. The aim of this study was to identify the structure of BO and evaluate the therapeutic effect of BO on 5-fluorouracil-induced intestinal mucosal inflammation.

Methods

BO were purified from DEAE52 cellulose. The structure of BO were characterised by HPGPC, GC-MS and NMR. In vivo, the mouse model of intestinal mucositis was established by intraperitoneal injection of 5-FU. The effect of BO on intestinal mucositis in mice was detected by assessing the levels of intestinal flora, ZO-1, occludin, and MUC-2, and inflammatory cytokines (IL-1β, IL-6, IL-10, and TNF-α).

Results

Structural characterisation showed that BO were the neutral polysaccharide composed mainly of glucose and mannose. The backbone of BO consisted of→4)-β-Manp-(1→, →4)-β-Glcp-(1→ and small →3,4)-α-Manp-(1→. The results of the in vivo experiment showed that the symptoms of diarrhoea, haematochezia and colonic mucosal lesions improved after administration of BO. Further experiments showed that BO not only reduced the levels of pro-inflammatory factors such as IL-1β, IL-6 and TNF-α, but also improved the expression of intestinal barrier protein and intestinal microbial community after BO treatment.

Conclusion

BO can relieve the progress of intestinal mucositis by relieving inflammation, protecting the intestinal epithelial barrier and regulating the intestinal microbiota. These data provide experimental evidence for the application of BO in chemotherapeutic intestinal mucositis.

Gymnemic acid alleviates gut barrier disruption and lipid dysmetabolism via regulating gut microbiota in HFD hamsters

Gut microbiota dysbiosis and gut barrier disruption are key events associated with high-fat diet (HFD)-induced systemic metabolic disorders. Gymnemic acid (GA) has been reported to have an important role in alleviating HFD-induced disorders of glycolipid metabolism, but its regulatory role in HFD-induced disorders of the gut microbiota and gut barrier function has not been elucidated. Here we showed that GA intervention in HFD-induced hamsters increased the relative abundance of short-chain fatty acid (SCFA)-producing microbes including Lactobacillus (P<.05) and Lachnoclostridium (P<.01) in the gut, and reduced the relative abundance of lipopolysaccharide (LPS)-producing microbes including Enterococcus (P<.05) and Bacteroides (P<.05), subsequently improving HFD-induced intestinal barrier dysfunction and systemic inflammation. Specifically, GA intervention reduced mRNA expression of inflammatory cytokines, including IL-1β, IL-6, and TNF-α (P<.01), increased mRNA expression of antioxidant-related genes, including Nfe2l2, Ho-1, and Nqo1 (P<.01), and increased mRNA expression of intestinal tight junction proteins, including Occludin and Claudin-1 (P<.01), thereby improving gut barrier function of HFD hamsters. This ameliorative effect of GA on the gut of HFD hamsters may further promote lipid metabolic balance in liver and adipose tissue by regulating the Toll-like receptor 4 (TLR4)-nuclear factor-κB (NF-κB) signaling pathway. Taken together, these results systematically revealed the important role of GA in regulating HFD-induced gut microbiota disturbance and gut barrier function impairment, providing a potential clinical theoretical basis for targeted treatment of HFD-induced microbiota dysbiosis.

Bletilla striata polysaccharides protect against ARDS by modulating the NLRP3/caspase1/GSDMD and HMGB1/TLR4 signaling pathways to improve pulmonary alveolar macrophage pyroptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Bletilla striata polysaccharides (BSP) extracted from the B. striata tuber, have been demonstrated to possess anti-inflammatory properties. However, their potential protective effect against ARDS and their role in regulating cell pyroptosis remained unexplored.

AIM OF THE STUDY

The aim of this study was to investigate the therapeutic effect of BSP in the alleviation of lipopolysaccharide (LPS)-induced ARDS, and to explore its mechanism of action.

METHODS

The effect of BSP was assessed by LPS injection into the intraperitoneal cavity in vivo; pathological changes of ARDS mice were gauged by immunohistochemical, hematoxylin and eosin staining, and immunofluorescence assays. MH-S cells were used to model the pyroptosis in vitro. Finally, the pyroptosis of alveolar macrophage was detected by western blots, qPCR, and flow cytometry for NLRP3/caspase1/GSDMD and HMGB1/TLR4 pathway-associated proteins and mRNA.

RESULTS

BSP could significantly increase the weight and survival rate of mice with ARDS, alleviate the cytokine storm in the lungs, and reduce lung damage in vivo. BSP inhibited the inflammation caused by LPS/Nigericin significantly in vitro. Compared with the control group, there was a remarkable surge in the incidence of pyroptosis observed in ARDS lung tissue and alveolar macrophages, whereas BSP significantly diminished the pyroptosis ratio. Besides, BSP reduced NLRP3/caspase1/GSDMD and HMGB1/TLR4 levels in ARDS lung tissue and MH-S cells.

CONCLUSIONS

These findings proved that BSP could improve LPS-induced ARDS via inhibiting pyroptosis, and this effect was mediated by NLRP3/caspase1/GSDMD and HMGB1/TLR4, suggesting a therapeutic potential of BSP as an anti-inflammatory agent for ARDS treatment.

Dual properties of pharmacological activities and preparation excipient: Bletilla striata polysaccharides

Bletilla striata has been used for thousands of years and shows the functions of stopping bleeding, reducing swelling, and promoting healing in traditional applications. For Bletilla striata, Bletilla striata polysaccharides (BSP) is the main active ingredient, exhibiting biological functions of anti-inflammatory, anti-oxidant, anti-fibrotic, immune modulation, anti-glycation, and so on. In addition, BSP has exhibited the characteristics of excipient such as bio-adhesion, bio-degradability, and bio-safety and has been prepared into a series of preparations such as nanoparticles, microspheres, microneedles, hydrogels, etc. BSP, as both a drug and an excipient, has already aroused more and more attention. In this review, publications in recent years related to the extraction and identification, biological activities, and excipient application of BSP are reviewed. Specifically, we focused on the advances in the application of BSP as a formulation excipient. We hold opinion that BSP not only needed more researches in the mechanisms, but also the development into hydrogels, nano-formulations, tissue engineering, and so on. And we believe that this paper provides a beneficial reference for further BSP innovation and in-depth research and promotes the use of these natural products in pharmaceutical applications.

Catalpol ameliorates LPS-induced inflammatory response by activating AMPK/mTOR signaling pathway in rat intestinal epithelial cells

Intestinal inflammation is a common clinical intestinal disease. Catalpol, a natural iridoid compound, has been shown to have anti-inflammatory, anti-oxidant and anti-apoptotic functions, but the mechanism of its protection against intestinal inflammation is still unclear. This study investigated the protective effect and potential mechanism of catalpol on the lipopolysaccharide (LPS)-induced inflammatory response of intestinal epithelial cell-6 (IEC-6). The results showed that catalpol could inhibit LPS-induced inflammatory response by dose-dependently reducing the release of inflammatory factors, such as tumor necrosis (TNF)-α, interleukin (IL)-1β and IL-6, and inhibiting the nuclear factor kappa-B (NF-κB) signaling pathway. Catalpol ameliorated cellular oxidative stress by reducing reactive oxygen species (ROS) and malondialdehyde (MDA) levels and increasing superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) expression. Meanwhile, catalpol also inhibited cell apoptosis, decreased the expression of B-cell lymphoma 2 (Bcl-2) - associated X (Bax), caspase 3 and caspase 9, and increased the expression of Bcl-2. This study found that catalpol activates AMP-activated protein kinase (AMPK) signaling pathway and inhibit mammalian target of rapamycin (mTOR) phosphorylationthe. In a further study, after inhibiting AMPK with dorsomorphin, the anti-inflammatory effects of catalpol were significantly reduced. Therefore, catalpol ameliorates LPS-induced inflammatory response by activating AMPK/mTOR signaling pathway in IEC-6 cells.

Extraction, structural-activity relationships, bioactivities, and application prospects of Bletilla striata polysaccharides as ingredients for functional products: A review

Bletilla striata is a well-known medicinal plant with high pharmaceutical and ornamental values. Polysaccharide is the most important bioactive ingredient in B. striata and has various health benefits. Recently, B. striata polysaccharides (BSPs) have attracted much attention from industries and researchers due to their remarkable immunomodulatory, antioxidant, anti-cancer, hemostatic, anti-inflammatory, anti-microbial, gastroprotective, and liver protective effects. Despite the successful isolation and characterization of B. striata polysaccharides (BSPs), there is still limited knowledge regarding their structure-activity relationships (SARs), safety concerns, and applications, which hinders their full utilization and development. Herein, we provided an overview of the extraction, purification, and structural features, as well as the effects of different influencing factors on the components and structures of BSPs. We also highlighted and summarized the diversity of chemistry and structure, specificity of biological activity, and SARs of BSP. The challenges and opportunities of BSPs in the food, pharmaceutical, and cosmeceutical fields are discussed, and the potential development and future study direction are scrutinized. This article provides comprehensive knowledge and underpinnings for further research and application of BSPs as therapeutic agents and multifunctional biomaterials.

Protective effect and mechanism insight of purified Antarctic kill phospholipids against mice ulcerative colitis combined with bioinformatics

Antarctic krill oil is functional oil and has a complex phospholipids composition that poses difficulties in elucidating its effect mechanism on ulcerative colitis (UC). The mechanism of UC action was studied by bioinformatics, and the therapeutic effect of Antarctic krill phospholipids (APL) on dextran sulfate sodium (DSS)-induced colitis mice was verified. GO functional enrichment analysis uncovered an enrichment of these genes in the regulation of cell-cell adhesion, membrane region, signaling receptor activator activity, and cytokine activity. Meanwhile, the KEGG results revealed the genes were enriched in the TNF signaling pathway, pathogenic Escherichia coli infection, inflammatory bowel disease and tight junction. Animal experiments showed that APL treatment alleviated the UC symptoms and reduced inflammatory damage. Meanwhile, the expressions of the tight junction (TJ) proteins, ZO-1 and occludin, were restored, and the levels of IL-6 and TNF-α were reduced. Moreover, Firmicutes/Bacteroidetes ratio in the intestinal microbiota was regulated, and the contents of short-chain fatty acids metabolites were raised. These findings would provide an insight for the beneficial effects of APL and dietary therapy strategies for UC.

Polysaccharides from Bletilla striata protect against mercury-induced gastrointestinal toxicology in adult Drosophila melanogaster via modulation of sestrin

Oxidative stress was one of the major causes of heavy metal-induced toxicity in organisms. The polysaccharide from Bletilla striata (Orchidaceae) (BSP) has been recently recognized as a novel player in the management of oxidative stress response in organisms. Here, we took the midgut of adult Drosophila melanogaster (Diptera: Drosophilidae) (D. melanogaster), a functional equivalent to the mammalian intestine and stomach, as a model to evaluate the protective effects of BSP (50 μg/mL) on mercuric chloride-induced gastrointestinal toxicology in insects. As a result, BSP exposure significantly improved the survival rates and climbing ability of adult flies exposed to mercury. Further study demonstrated that BSP significantly alleviated the mercury-induced oxidative injury to midgut epithelium, at least partly, through increasing antioxidant enzyme activity (glutathione-S-transferase and superoxide dismutase), decreasing reactive oxidative species production, inhibiting cell death, restoring intestinal epithelial barrier and regulating intestinal stem cell-mediated tissue regeneration. Additionally, sestrin, an oxidative-stress gene, was required in mediating the protection of BSP against mercury-induced oxidative damage to midgut. This study suggested that BSP has great potential for future application in the treatment and prevention of heavy metal-induced gastrointestinal adversities in mammals.

Lipopolysaccharide promotes apoptosis and oxidative injury of porcine small intestinal epithelial cells by down-regulating the expression of glutamine transporter ASCT2

The present study aimed to investigate the effects of lipopolysaccharide (LPS) stimulation on oxidative damage, apoptosis, and glutamine (Gln) transporter Alanine-Serine-Cysteine transporter 2 (ASCT2) expression in porcine small intestinal epithelial cells (IPEC-J2), and preliminarily elucidated the relationship between ASCT2 expression level and oxidative damage and apoptosis of IPEC-J2 cells. IPEC-J2 cells were treated without (control group, CON, N = 6) or with 1 μg/mL LPS (LPS group, LPS, N = 6). Cell viability, lactate dehydrogenase (LDH) content, malonaldehyde (MDA), anti-oxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GSH-Px], and total anti-oxidant capacity [T-AOC]), apoptosis of IPEC-J2 cells, the expression of Caspase3, the expression of ASCT2 mRNA and ASCT2 protein was detected. The results showed that LPS stimulation of IPEC-J2 cells significantly reduced the cell viability, and anti-oxidant enzymes activity (SOD, CAT, and GSH-Px), and significantly increased LDH and MDA release. Flow cytometry results showed that LPS stimulation significantly increased the late apoptosis rate and the total apoptosis rate of IPEC-J2 cells. The immunofluorescence results showed that the fluorescence intensity of LPS stimulated IPEC-J2 cells was significantly enhanced. LPS stimulation significantly decreased the mRNA and protein expression of ASCT2 in IPEC-J2 cells. The correlation analysis showed that ASCT2 expression was negatively correlated with apoptosis, and positively correlated with the anti-oxidant capacity of IPEC-J2 cells. According to the results of this study, it can be preliminarily concluded that LPS promotes the apoptosis and oxidative injury of IPEC-J2 cells by down-regulating the expression of ASCT2.

Polysaccharide-Based Edible Gels as Functional Ingredients: Characterization, Applicability, and Human Health Benefits

Nowadays, edible materials such as polysaccharides have gained attention due to their valuable attributes, especially gelling property. Polysaccharide-based edible gels (PEGs) can be classified as (i) hydrogels, (ii) oleogels and bigels, (iii) and aerogels, cryogels and xerogels, respectively. PEGs have different characteristics and benefits depending on the functional groups of polysaccharide chains (e.g., carboxylic, sulphonic, amino, methoxyl) and on the preparation method. However, PEGs are found in the incipient phase of research and most studies are related to their preparation, characterization, sustainable raw materials, and applicability. Furthermore, all these aspects are treated separately for each class of PEG, without offering an overview of those already obtained PEGs. The novelty of this manuscript is to offer an overview of the classification, definition, formulation, and characterization of PEGs. Furthermore, the applicability of PEGs in the food sector (e.g., food packaging, improving food profile agent, delivery systems) and in the medical/pharmaceutical sector is also critically discussed. Ultimately, the correlation between PEG consumption and polysaccharides properties for human health (e.g., intestinal microecology, "bridge effect" in obesity, gut microbiota) are critically discussed for the first time. Bigels may be valuable for use as ink for 3D food printing in personalized diets for human health treatment. PEGs have a significant role in developing smart materials as both ingredients and coatings and methods, and techniques for exploring PEGs are essential. PEGs as carriers of bioactive compounds have a demonstrated effect on obesity. All the physical, chemical, and biological interactions among PEGs and other organic and inorganic structures should be investigated.

Inhibition of visfatin alleviates sepsis-induced intestinal damage by inhibiting Hippo signaling pathway

Background

The aim of this study is to investigate role of Visfatin, one of the pro-inflammatory adipokines, in sepsis-induced intestinal injury and to clarify the potential mechanism.

Methods

C57BL/6 mice underwent cecal ligation and puncture (CLP) surgery to establish sepsis model in vivo. Intestinal epithelial cells were stimulated with LPS to mimic sepsis-induced intestinal injury in vitro. FK866 (the inhibitor of Visfatin) with or without XMU-MP-1 (the inhibitor of Hippo signaling) was applied for treatment. The expression levels of Visfatin, NF-κB and Hippo signaling pathways-related proteins were detected by western blot or immunohistochemistry. The intestinal cell apoptosis and intestinal injury were investigated by TUNEL staining and H&E staining, respectively. ELISA was used to determine the production of inflammatory cytokines.

Results

The expression of Visfatin increased in CLP mice. FK866 reduced intestinal pathological injury, inflammatory cytokines production, and intestinal cell apoptosis in sepsis mice. Meanwhile, FK866 affected NF-κB and Hippo signaling pathways. Additionally, the effects of FK866 on inflammatory response, apoptosis, Hippo signaling and NF-κB signaling were partly abolished by XMU-MP-1, the inhibitor of Hippo signaling. In vitro experiments also revealed that FK866 exhibited a protective role against LPS-induced inflammatory response and apoptosis in intestinal cells, as well as regulating NF-κB and Hippo signaling, whereas addition of XMU-MP-1 weakened the protective effects of FK866.

Conclusion

In short, this study demonstrated that inhibition of Visfatin might alleviate sepsis-induced intestinal injury through Hippo signaling pathway, supporting a further research on Visfatin as a therapeutic target.

A Dual-Cross-Linked Hydrogel Patch for Promoting Diabetic Wound Healing

Diabetic wound treatment faces significant challenges in clinical settings. Alternative treatment approaches are needed. Continuous bleeding, disordered inflammatory regulation, obstruction of cell proliferation, and disturbance of tissue remodeling are the main characteristics of diabetic wound healing. Hydrogels made of either naturally derived or synthetic materials can potentially be designed with a variety of functions for managing the healing process of chronic wounds. Here, a hemostatic and anti-inflammatory hydrogel patch is designed for promoting diabetic wound healing. The hydrogel patch is derived from dual-cross-linked methacryloyl-substituted Bletilla Striata polysaccharide (B) and gelatin (G) via ultraviolet (UV) light. It is demonstrated that the B-G hydrogel can effectively regulate the M1/M2 phenotype of macrophages, significantly promote the proliferation and migration of fibroblasts in vitro, and accelerate angiogenesis. It can boost wound closure by normalizing epidermal tissue regeneration and depositing collagen appropriately in vivo without exogenous cytokine supplementation. Overall, the B-G bioactive hydrogel can promote diabetic wound healing in a simple, economical, effective, and safe manner.

Interplay between gut microbiota and bile acids in diarrhoea-predominant irritable bowel syndrome: a review

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disease that disturbs the physiology and psychology of patients and increases the burden on families, the healthcare system, society, and economic development, affecting more and more people around the world. Despite the multiple factors that account for IBS remaining incompletely studied, emerging evidence demonstrated the abnormal changes in gut microbiota and bile acids (BAs) metabolism closely associated with IBS. Moreover, microbiota drives significant modifications for BAs, consisting of deconjugation, 7α-dehydroxylation, oxidation, epimerization, desulfation, esterification, and so on, while BAs, in turn, affect the microbiota directly or indirectly. In light of the complex connection among gut microbiota, BAs, and IBS, it is urgent to review the latest research progress in this field. In this review, we described the disorders of intestinal microecology and BAs profiles in IBS-D and also highlighted the cross-talk between gut microbiota and BAs in the context of IBS-D. Integrating these, we suggest that new therapeutic strategies targeting the microbiota-BAs axis for IBS-D, even for other related diseases caused by bacteria-bile acid dysbiosis should be expected.

Investigation into the physical properties, antioxidant and antibacterial activity of Bletilla striata polysaccharide/chitosan membranes

Traditional wound dressings and formulations, such as cream, gauze, cotton wool and gel, are disadvantaged by short residence time, poor leakage and air permeability, poor patient compliance, and the minimal preservation in wet environment. This study is purposed to develop new biodegradable, antioxidant, and antimicrobial membranes based on two natural polysaccharides, Bletilla striata polysaccharide (BSP) and chitosan (CS). The developed films were characterized by SEM, FTIR spectroscopy, NMR spectroscopy and X-ray diffraction to examine surface morphology and internal structure, while TG analysis was conducted to explore the thermal properties of the films. The physical properties of the films were also improved significantly after the introduction of BSP. The biological activity of developed films was assessed by means of antioxidant and antibacterial assay for the further research as a potential wound dressing. The CCK-8 assay revealed that the developed films showed a significant improvement of cell viability, biocompatibility and non-toxicity. These researches demonstrated that BSP/CS films can be applied as suitable materials for the development of biomaterial matrix in novel wound dressing.

Gut Microbiota-Bile Acid Crosstalk in Diarrhea-Irritable Bowel Syndrome

The occurrence of diarrhea-predominant irritable bowel syndrome (IBS-D) is the result of multiple factors, and its pathogenesis has not yet been clarified. Emerging evidence indicates abnormal changes in gut microbiota and bile acid (BA) metabolism have a close relationship with IBS-D. Gut microbiota is involved in the secondary BA production via deconjugation, 7α-dehydroxylation, oxidation, epimerization, desulfation, and esterification reactions respectively. Changes in the composition and quantity of gut microbiota have an important impact on the metabolism of BAs, which can lead to the occurrence of gastrointestinal diseases. BAs, synthesized in the hepatocytes, play an important role in maintaining the homeostasis of gut microbiota and the balance of glucose and lipid metabolism. In consideration of the complex biological functional connections among gut microbiota, BAs, and IBS-D, it is urgent to review the latest research progress in this field. In this review, we summarized the alterations of gut microbiota in IBS-D and discussed the mechanistic connections between gut microbiota and BA metabolism in IBS-D, which may be involved in activating two important bile acid receptors, G-protein coupled bile acid receptor 1 (TGR5) and farnesoid X receptor (FXR). We also highlight the strategies of prevention and treatment of IBS-D via regulating gut microbiota-bile acid axis, including probiotics, fecal microbiota transplantation (FMT), cholestyramine, and the cutting-edge technology about bacteria genetic engineering.

De novo sequencing of Bletilla striata (Orchidaceae) transcriptome and identification of genes involved in polysaccharide biosynthesis

Bletilla striata polysaccharide (BSP) is the main component of Bletilla striata, which has important pharmacological and pharmacological effects; however, due to the lack of genetic data, the metabolic pathways of BSP remain unclear. For this study, 11 representative resources of B. striata were analyzed, and the BSP contents of the different samples were significantly different; however, the monosaccharide composition of BSP was glucose and mannose. The representative samples were selected to observe their life history in situ, which were then divided and cultured in a greenhouse. Finally, samples from various organs of different plants were combined for transcriptome sequencing using the Illumina system. Our results summarized the BSP metabolic pathway, and we found that there were eight enzyme genes involved in biosynthesis, but these genes showed tissue specificity. Following qRT-PCR validation and comparative analysis, manA showed the highest expression; however, there were significant differences between the two germplasm resources in which the BSP content was significantly different, while UGP2, GPI, PMM, and GMPP had significant differences between the two samples. In summary, this study lays the foundation for further research into BSP metabolism and other physiological processes at the molecular level.

A Review of Isolation, Chemical Properties, and Bioactivities of Polysaccharides from Bletilla striata

Recently, polysaccharides from Bletilla striata, a member of the orchidaceous family, aroused the wide interest of people, especially their isolation, chemical properties, and bioactivities. It is reported that these polysaccharides are the most important biologically active components of B. striata, exhibiting various biological activities, such as immunomodulatory, antioxidant, antifibrotic, and hemostatic effects. This review appraised the available literatures which described different aspects of B. striata polysaccharides, including the extraction, separation, purification, structural characterization, and biological activities. We expect to lay the foundation for further investigation of the application of B. striata polysaccharides in the field of functional foods and biomedicine.

Effective fraction of Bletilla striata reduces the inflammatory cytokine production induced by water and organic extracts of airborne fine particulate matter (PM2.5) in vitro

BACKGROUND

Bletilla striata is a traditional Chinese medicine used to treat hemorrhage, scald, gastric ulcer, pulmonary diseases and inflammations. In this study, we investigated bioactivity of the effective fraction of B. striata (EFB) in reducing the inflammatory cytokine production induced by water or organic extracts of PM2.5.

METHODS

PM2.5 extracts were collected and analyzed by chromatographic system and inductively coupled plasma mass spectrometer. Cell viability was measured using MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay, and cell supernatant was analyzed by flow cytometry, ELISA, and qRT-PCR in cultured mouse macrophage cell line RAW264.7 treated with EFB and PM2.5 extracts. Expressions of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathway were measured by Western blot.

RESULTS

PM2.5 composition is complex and the toxicity of PM2.5 extracts were not noticeable. The treatment of EFB at a wide dose-range of 0-40 μg/mL did not cause significant change of RAW264.7 cell proliferation. EFB pretreatment decreased the inflammatory cytokines in the macrophage. Further analysis showed that EFB significantly attenuated PM2.5-induced proinflammatory protein expression and downregulated the levels of phosphorylated NF-κBp65, inhibitor of kappa B (IκB)-α, c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p38.

CONCLUSIONS

Our study demonstrated the potential effectiveness of B. striata extracts for treating PM2.5-triggered pulmonary inflammation.