Reduced allergic lung inflammation by root extracts from two species of Peucedanum through inhibition of Th2 cell activation

A chromosome-scale genome of Peucedanum praeruptorum provide insights into Apioideae evolution and medicinal ingredient biosynthesis

Peucedanum praeruptorum Dunn, a traditional Chinese medicine rich in coumarin, belongs to the Apiaceae family. A high-quality assembled genome of P. praeruptorum is lacking, which has posed obstacles to functional identification and molecular evolution studies of genes associated with coumarin production. Here, a chromosome-scale reference genome of P. praeruptorum, an important medicinal and aromatic plant, was first sequenced and assembled using Oxford Nanopore Technologies and Hi-C sequencing. The final assembled genome size was 1.83 Gb, with a contig N50 of 11.12 Mb. The entire BUSCO evaluation and second-generation read comparability rates were 96.0 % and 99.31 %, respectively. Furthermore, 99.91 % of the genome was anchored to 11 pseudochromosomes. The comparative genomic study revealed the presence of 18,593 orthogroups, which included 476 species-specific orthogroups and 1211 expanded gene families. Two whole-genome duplication (WGD) events and one whole-genome triplication (WGT) event occurred in P. praeruptorum. In addition to the γ-WGT shared by core eudicots or most eudicots, the first WGD was shared by Apiales, while the most recent WGD was unique to Apiaceae. Our study demonstrated that WGD events that occurred in Apioideae highlighted the important role of tandem duplication in the biosynthesis of coumarins and terpenes in P. praeruptorum. Additionally, the expansion of the cytochrome P450 monooxygenase, O-methyltransferase, ATP-binding cassette (ABC) transporter, and terpene synthase families may be associated with the abundance of coumarins and terpenoids. Moreover, we identified >170 UDP-glucosyltransferase members that may be involved in the glycosylation post-modification of coumarins. Significant gene expansion was observed in the ABCG, ABCB, and ABCC subgroups of the ABC transporter family, potentially facilitating the transmembrane transport of coumarins after bolting. The P. praeruptorum genome provides valuable insights into the machinery of coumarin biosynthesis and enhances our understanding of Apiaceae evolution.

Genome sequencing-based transcriptomic analysis reveals novel genes in Peucedanum praeruptorum

BACKGROUND

Peucedanum praeruptorum Dunn, a traditional Chinese herbal medicine, contains coumarin and volatile oil components that have clinical application value. However, early bolting often occurs in the medicinal materials of Apiaceae plants. The rhizomes of the medicinal parts are gradually lignified after bolting, resulting in a sharp decrease in the content of coumarins. At present, the link between coumarin biosynthesis and early bolting in P. praeruptorum has not been elucidated.

RESULTS

Combining the genome sequencing and the previous transcriptome sequencing results, we reanalyzed the differential transcripts of P. praeruptorum before and after bolting. A total of 62,088 new transcripts were identified, of which 31,500 were unknown transcripts. Functional classification and annotation showed that many genes were involved in the regulation of transcription, defense response, and carbohydrate metabolic processes. The main domains are the pentatricopeptide repeat, protein kinase, RNA recognition motif, leucine-rich repeat, and ankyrin repeat domains, indicating their pivotal roles in protein modification and signal transduction. Gene structure analysis showed that skipped exon (SE) was the most dominant alternative splicing, followed by the alternative 3' splice site (A3SS) and the alternative 5' splice site (A5SS). Functional enrichment of differentially expressed genes showed that these differentially expressed genes mainly include transmembrane transporters, channel proteins, DNA-binding proteins, polysaccharide-binding proteins, etc. In addition, genes involved in peroxisome, hexose phosphate pathway, phosphatidylinositol signaling system, and inositol phosphate metabolism pathway were greatly enriched. A protein-protein interaction network analysis discoverd 1,457 pairs of proteins that interact with each other. The expression levels of six UbiA genes, three UGT genes, and four OMT genes were higher during the bolting stage. This observation suggests their potential involvement in the catalytic processes of prenylation, glycosylation, and methylation of coumarins, respectively. A total of 100 peroxidase (PRX) genes were identified being involved in lignin polymerization, but only nine PRX genes were highly expressed at the bolting stage. It is worth noting that 73 autophagy-related genes (ATGs) were first identified from the KEGG pathway-enriched genes. Some ATGs, such as BHQH00009837, BHQH00013830, and novel8944, had higher expression levels after bolting.

CONCLUSIONS

Comparative transcriptome analysis and large-scale genome screening provide guidance and new opinions for the identification of bolting-related genes in P. praeruptorum.

Fungal isolates influence the quality of Peucedanum praeruptorum Dunn

The symbiotic relationship between beneficial microorganisms and plants plays a vital role in natural and agricultural ecosystems. Although Peucedanum praeruptorum Dunn is widely distributed, its development is greatly limited by early bolting. The reason for early bolting in P. praeruptorum remains poorly characterized. We focus on the plant related microorganisms, including endophytes and rhizosphere microorganisms, by combining the traditional isolation and culture method with metagenomic sequencing technology. We found that the OTUs of endophytes and rhizosphere microorganisms showed a positive correlation in the whole growth stage of P. praeruptorum. Meanwhile, the community diversity of endophytic and rhizosphere fungi showed an opposite change trend, and bacteria showed a similar change trend. Besides, the microbial communities differed during the pre- and post-bolting stages of P. praeruptorum. Beneficial bacterial taxa, such as Pseudomonas and Burkholderia, and fungal taxa, such as Didymella and Fusarium, were abundant in the roots in the pre-bolting stage. Further, a strain belonging to Didymella was obtained by traditional culture and was found to contain praeruptorin A, praeruptorin B, praeruptorin E. In addition, we showed that the fungus could affect its effective components when it was inoculated into P. praeruptorum. This work provided a research reference for the similar biological characteristics of perennial one-time flowering plants, such as Saposhnikovia divaricate, Angelica sinensis and Angelica dahurica.

The Root Extract of Peucedanum praeruptorum Dunn Exerts Anticancer Effects in Human Non-Small-Cell Lung Cancer Cells with Different EGFR Mutation Statuses by Suppressing MET Activity

The aim of this study was to investigate the anticancer effects of the root extract of Peucedanum praeruptorum Dunn (EPP) in human non-small-cell lung cancer (NSCLC) cells and explore the mechanisms of action. We used four types of human lung cancer cell lines, including H1299 (epidermal growth factor receptor (EGFR) wild-type), PC9 (EGFR Glu746-Ala750 deletion mutation in exon 19; EGFR tyrosine kinase inhibitor (TKI)-sensitive), H1975 (EGFR L858R/T790M double-mutant; EGFR TKI-resistant), and PC9/ER (erlotinib-resistant) cells. EPP suppressed cell growth and the colony formation of NSCLC cells in a concentration-dependent manner. EPP stimulated chromatin condensation, increased the percentage of sub-G1 phase cells, and enhanced the proportion of annexin V-positive cells, demonstrating that EPP triggered apoptosis in NSCLC cells regardless of the EGFR mutation and EGFR TKI resistance status. The phosphorylation level of the signal transducer and activator of transcription 3 (STAT3) and AKT was decreased by EPP. The expression of STAT3 target genes was also downregulated by EPP. EPP reversed hepatocyte growth factor (HGF)-induced MET phosphorylation and gefitinib resistance. Taken together, our results demonstrate that EPP exerted anticancer effects not only in EGFR TKI-sensitive NSCLC cells, but also in EGFR TKI-resistant NSCLC cells, by suppressing MET activity.

Rapid Identification of Peucedanum Praeruptorum Dunn and its Adulterants by Hand-Held near-Infrared Spectroscopy

Peucedanum praeruptorum Dunn (PPD) is a traditional Chinese medical herb of high medical and economic value. However, PPD is often pretended by inexpensive plants. To establish an integrated methodology using hand-held near-infrared spectroscopy (NIRS) combined with chemical pattern recognition techniques to identify adulterated PPD products. The standard normal variate (SNV) was used to preprocess the original near-infrared spectra. Principal component analysis (PCA), linear discriminant analysis (LDA), and partial least squares regression analysis (PLSDA) were used to construct the recognition models. PCA analysis could not correctly distinguish PPD from non-PPD. However, based on absorbance in the spectral region of 1,405-2,442 nm and SVN pretreatment, the accuracy of the LDA model was above 90% at identifying genuine PPD. Compared with the LDA method, the PLSDA model is more stable and reliable, and its model prediction accuracy was 93.4%. The combination of near-infrared spectroscopy and chemometric methods based on a hand-held near-infrared spectrometer is an efficient, non-destructive, and reliable method for validating traditional Chinese medicine PPD. It can be used for rapid identification and quality evaluation of PPD in the field, medicinal material markets, and points of sale.

Effects of Dipsacus asperoides and Phlomis umbrosa Extracts in a Rat Model of Osteoarthritis

The implementation of the Nagoya Protocol highlighted the importance of identifying alternative herbal products that are as effective as traditional medicine. Dipsacus asperoides and Phlomis umbrosa, two species used in the Korean medicine ‘Sok-dan’, are used for the treatment of bone- and arthritis-related diseases, and they are often mixed or misused. To identify herbal resources with similar efficacy, we compared the effects of D. asperoides extract (DAE) and P. umbrosa extract (PUE) on osteoarthritis (OA) in a monosodium iodoacetate (MIA)-induced OA rat model. Weight-bearing distribution, serum cytokines, histopathological features, and the expression of matrix metalloproteinases (MMPs) of knee joint tissues were examined in the OA rats treated with DAE and PUE (200 mg/kg) for 21 days. DAE and PUE restored weight-bearing distribution, inhibited the production of serum cytokines, and alleviated the histopathological features of the OA knee tissue. DAE or PUE treatment decreased OA-induced overexpression of MMP-2, MMP-9, and MMP-13 in the knee joint tissue. This study demonstrated the efficacy of both DAE and PUE in an MIA-induced OA model, providing a basis for the clinical use of these products in traditional Korean medicine.

An LC-MS/MS Method for the Pharmacokinetic and in Vitro Metabolism Studies of Praeruptorin A in Rat

Objective:

The study aims to investigate the pharmacokinetic profile of Praeruptorin A and khellactone and in vitro hydrolysis of praeruptorin A to khellactone in different biological samples.

Methods:

A LC-MS/MS method was established. Analytes and internal standard (IS) were isolated using the protein precipitation method and then separated on a Thermo BDS Hypersil C18 (2.1 mm×50 mm, 2.4μm) column using a mobile phase consisting of 0.05% formic acid solution and acetonitrile. Samples were analyzed in positive electrospray-ionization (ESI) mode using multiple reaction monitoring (MRM).

Results:

The calibration plots gave desirable linearity (r2>0.99) in the concentration range from 0.99-990.0 and 2.0-2000.0 ng/mL for Praeruptorin A and khellactone, respectively. In addition, the LOQs of these analytes were sufficient for vivo pharmacokinetic study and vitro hydrolysis study of Praeruptorin A. The intra-batch and inter-batch precision were all within 14.05%, and the accuracy was between 89.39% and 109.50%. The extraction efficiency of PA and khellactone ranged from 76.35 ~ 89.58%. The matrix effects of analytes and the IS were between 89.67% ~ 105.26%.

Conclusion:

The liver CYPs mediated by the metabolism of PA may contribute to the systemic exposure of its active metabolite, khellactone, in rats.

De novo Transcriptome Sequencing Coupled With Co-expression Analysis Reveal the Transcriptional Regulation of Key Genes Involved in the Formation of Active Ingredients in Peucedanum praeruptorum Dunn Under Bolting Period

Peucedanum praeruptorum Dunn is a perennial and one-off flowering plant of the Peucedanum genus in Umbelliferae. The cultivated P. praeruptorum Dunn usually grows nutritionally in the first year and then moves into the reproductive growth in the second year. The lignification of the roots caused by bolting leads to the quality decline of crude materials. Since most of the previous studies have dealt with coumarin biosynthesis and identification of functional genes in P. praeruptorum, the scientific connotation of the inability that the bolted P. praeruptorum cannot be used medically is still unclear. Here, we employed a transcriptome sequencing combined with coexpression analysis to unearth the regulation mechanism of key genes related to coumarin synthesis in pre- and postbolting period, and to explore the mechanisms underlying the effects of bolting on the formation and transport of coumarins between the annual and biennial plants. Six cDNA libraries were constructed, and the transcripts were sequenced and assembled by Illumina Hiseq platform. A total of 336,505 unigenes were obtained from 824,129 non-redundant spliced transcripts. Unigenes (114,488) were annotated to the NCBI nr database, 119,017 and 10,475 unigenes were aligned to Gene Ontology (GO) functional groups and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, respectively. Differential expression analysis screened out a series of upregulated and downregulated genes related to the phenylpropanoid pathway. The heatmap clustering showed that the similar expression patterns were both observed in groups C vs. D and groups C vs. F. The WGCNA-based coexpression was performed to elucidate the module and trait relationship to unearth important genes related to the bolting process. Seven pivotal modules on the KEGG functional annotations suggested these genes were mainly enriched in the process of plant–pathogen interaction, plant hormone signal transduction, MAPK signaling pathway, α-linolenic acid metabolism, circadian rhythm, and phenylpropanoid pathway. Further analysis provided clues that the key genes of the phenylpropanoid pathway, the ABC transporters, the apoptosis-related and circadian rhythm regulatory genes may play pivotal roles in regulating bolting signaling, biosynthesis, and transportation of coumarins.

Simultaneous Determination of Five Coumarins in Peucedanum Decursivum Radix by UPLC

OBJECTIVE

To establish an ultra-high performance liquid chromatography (UPLC) method for simultaneous determination of umbelliferonel, nodakenin, psoralen, xanthotoxin and bergapten contents in Peucedanum decursivum Radix.

METHODS

The analysis was achieved on a Symmetry®C18 column (4.6 mm × 250 mm, 5 μm), with acetonitrile and water as the mobile phase in gradient elution mode. The column temperature was maintained at 30°C, with flow rate 1.0 mL·min-1. The injection volume of sample was 10 μL. The ultraviolet detection wavelength was set at the maximum absorption wavelength 325 nm for umbelliferonel and nodakenin, 259 nm for psoralen, xanthotoxin and bergapten, respectively.

RESULTS

The five kinds of coumarins in Peucedanum decursivum Radix were separated well and the linear relation was obtained (R2 ≥ 0.9998). The average recoveries were 101.31, 105.27, 90.85, 106.42 and 90.19%, respectively, with Relative standard deviation (RSD) 3.07, 3.17, 1.62, 2.53 and 4.54%, respectively.

CONCLUSIONS

The established method was accurate and feasible, which could be used as the basis of quality control of Peucedanum decursivum Radix.

Root extract of Angelica reflexa B.Y.Lee reduces allergic lung inflammation by regulating Th2 cell activation

ETHNOPHARMACOLOGICAL RELEVANCE

Traditionally, the roots of Angelica reflexa B.Y.Lee (AR) have been used to treat cough, phlegm, neuralgia, and arthralgia in Northeast Asia.

AIM OF THE STUDY

The anti-asthmatic effect of AR root extract (ARE) was determined using a murine airway allergic inflammation model and the primary T cell polarization assay.

MATERIALS AND METHODS

To evaluate the anti-asthmatic effect of ARE, inflammatory cell infiltration was determined histologically and inflammatory mediators were measured in bronchoalveolar lavage fluid (BALF). Furthermore, the effects of AREs on Th2 cell differentiation and activation were determined by western blotting and flow cytometry.

RESULTS

Asthmatic phenotypes were alleviated by ARE treatment, which reduced mucus production, inflammatory cell infiltration (especially eosinophilia), and type 2 cytokine levels in BALF. ARE administration to mice reduced the number of activated Th2 (CD4⁺CD25⁺) cells and level of GATA3 in the lungs. Furthermore, ARE treatment inhibited the differentiation of Th2 cells in primary cell culture systems via interferon regulatory factor 4 (IRF4) signaling.

CONCLUSIONS

Our findings indicate that the anti-asthmatic effect of AREs is mediated by the reduction in Th2 cell activation by regulating IRF4.

Sojadodamgangki-tang attenuates allergic lung inflammation by inhibiting T helper 2 cells and Augmenting alveolar macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

Sojadodamgangki-tang (SDG) is a traditional East-Asian herbal medicine mainly composed of Pinellia ternate (Thunb.) Makino, Perilla frutescens (L.) Britt and 10 kinds of medicinal herbs. It has been used to treat asthma and mucus secretion including lung and bronchi.

AIM OF THE STUDY

The aim of this study was to investigate the anti-inflammatory effects of Sojadodamgangki-tang (SDG) on allergic lung inflammation in vitro and in vivo as well as the underlying mechanisms.

MATERIALS AND METHODS

We used an ovalbumin (OVA)-induced murine allergic airway inflammation model. Five groups of 8-week-old female BALB/C mice were divided into the following groups: saline control group, the vehicle (allergic) group that received OVA only, groups that received OVA and SDG (200 mg/kg or 400 mg/kg), and a positive control group that received OVA and Dexamethasone (5 mg/kg). In vitro experiments include T helper 2 (TH2) polarization system, murine macrophage cell culture, and human bronchial epithelial cell line (BEAS-2B) culture.

RESULTS

SDG administration reduced allergic airway inflammatory cell infiltration, especially of eosinophils, mucus production, Th2 cell activation, OVA-specific immunoglobulin E (IgE), and total IgE production. Moreover, the activation of alveolar macrophages, which leads to immune tolerance in the steady state, was promoted by SDG treatment. Interestingly, SDG treatment also reduced the production of alarmin cytokines by the human bronchial epithelial cell line BEAS-2B stimulated with urban particulate matter.

CONCLUSION

Our findings indicate that SDG has potential as a therapeutic drug to inhibit Th2 cell activation and promote alveolar macrophage activation.

Anti-inflammatory effects of Samsoeum, a Korean medicine for health insurance, on chronic bronchitis caused by lipopolysaccharide in rats

BACKGROUND

Samsoeum (SSE), a Korean medicine, has been used to treat upper respiratory infection including residual coughs after catching a cold, and colds in patients with gastrointestinal disorder. In this study, we investigated the inhibitory effect of SSE against lipopolysaccharide (LPS)-induced bronchitis and characterized its optimal dosing range based on the improvement of SSE concentrations.

MATERIALS AND METHODS

Male Sprague Dawley rats were intra-nasally administered LPS on day 0, 3 and 6. 2 g kg-1 dose of SSE for rat was determined by the human equivalent dose formula and orally administered once a day from day 3 to day 6. To clarify the optimal administration dose of SSE, various doses including 0.5 (1/4 fold), 1 (1/2 fold), 6 (3 fold), 12 (6 fold), 24 (12 fold) and 36 g kg-1 (18 fold) were also orally administered. In addition, the molecular mechanism of SSE in mucin hyperproduction was investigated in LPS-sensitized A549 cells.

RESULTS

Oral administration of SSE ameliorated alveolar wall thickening and inflammatory cell infiltration of lung tissues in LPS-induced bronchitis at doses of 1/4 fold, 1/2 fold and 1 fold. The total cell and neutrophil numbers in bronchoalveolar lavage fluid (BALF) were reduced in the SSE-treated groups compared with the LPS group. In addition, 0.5, 1 and 2 g kg-1 of SSE suppressed LPS-induced mucin glycoprotein 5AC (MUC5AC) production in BALF. Furthermore, SSE treatment significantly inhibited the pro-inflammatory cytokines, resulting in the decrease of MUC5AC production by the JAK1/STAT6 signaling pathway.

CONCLUSIONS

1, 2 and 6 g kg-1 of SSE ameliorated chronic bronchitis by inhibiting LPS-induced neutrophil infiltration and MUC5AC release in BALF. These findings suggested that SSE with 0.5-3-fold of general daily intake dose would be a therapeutic agent for chronic bronchitis.

Use of Natural Products in Asthma Treatment

Asthma, a disease classified as a chronic inflammatory disorder induced by airway inflammation, is triggered by a genetic predisposition or antigen sensitization. Drugs currently used as therapies present disadvantages such as high cost and side effects, which compromise the treatment compliance. Alternatively, traditional medicine has reported the use of natural products as alternative or complementary treatment. The aim of this review was to summarize the knowledge reported in the literature about the use of natural products for asthma treatment. The search strategy included scientific studies published between January 2006 and December 2017, using the keywords "asthma," "treatment," and "natural products." The inclusion criteria were as follows: (i) studies that aimed at elucidating the antiasthmatic activity of natural-based compounds or extracts using laboratory experiments (in vitro and/or in vivo); and (ii) studies that suggested the use of natural products in asthma treatment by elucidation of its chemical composition. Studies that (i) did not report experimental data and (ii) manuscripts in languages other than English were excluded. Based on the findings from the literature search, aspects related to asthma physiopathology, epidemiology, and conventional treatment were discussed. Then, several studies reporting the effectiveness of natural products in the asthma treatment were presented, highlighting plants as the main source. Moreover, natural products from animals and microorganisms were also discussed and their high potential in the antiasthmatic therapy was emphasized. This review highlighted the importance of natural products as an alternative and/or complementary treatment source for asthma treatment, since they present reduced side effects and comparable effectiveness as the drugs currently used on treatment protocols.

Anti-asthmatic effects of lepidii seu Descurainiae Semen plant species in ovalbumin-induced asthmatic mice

ETHNOPHARMACOLOGICAL EVIDENCE

Lepidii seu Descurainiae Semen (LDS) is used as a traditional herbal medicine in northeast Asia, mainly in Korea, Japan, and China to treat lung disorders including coughs and phlegm caused by acute and chronic airway inflammation.

AIM OF THE STUDY

Recently, interest regarding health problems incurred by air pollution has rapidly grown. Herbal medicines are being considered as alternative agents to treat various diseases. In the present study, we evaluated and compared the anti-inflammatory effects of LDS, which is derived from Lepidium apetalum Willd. extracts (LAE) and Descurainia sophia (L.) Webb ex Prantl extracts (DSE), on allergic airway inflammation.

MATERIALS AND METHODS

We established an ovalbumin-induced asthmatic mouse model to evaluate the efficacy of LDS extracts. We performed histological examination and measured relevant inflammatory mediators and cells in bronchoalveolar lavage fluid and lung. Furthermore, we conducted an in vitro T helper 2 (Th2) polarization assay, flow cytometry, and western blot analysis.

RESULTS

Asthmatic phenotypes were attenuated by LDS extract treatments. LDS extract administration significantly reduced mucus production, inflammatory cell infiltration into airways, and eosinophil activation. Furthermore, LDS extracts reduced the expression of type 2 cytokines and inhibited differentiation and activation of Th2 cells.

CONCLUSION

LDS alleviated eosinophilic inflammation by inhibiting Th2 cell differentiation, and DSE was more effective in attenuating allergic lung inflammation than LAE.

Tissue-Specific Metabolite Profiling on the Different Parts of Bolting and Unbolting Peucedanum praeruptorum Dunn (Qianhu) by Laser Microdissection Combined with UPLC-Q/TOF⁻MS and HPLC⁻DAD

BACKGROUND

Qianhu is a traditional Chinese medicine. It is thought that Qianhu roots will harden after bolting and not be suitable for medicinal purposes. Bolting Qianhu and unbolting Qianhu are referred to as "Xiong Qianhu" and "Ci Qianhu," respectively. In this study, the properties, microscopic and chemical characteristics of Ci Qianhu and Xiong Qianhu roots were compared using fluorescence microscopy, laser microdissection coupled with ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry, and high-performance liquid chromatography with diode-array detection.

RESULTS

Microscopy results showed that the area of secondary xylem in the root increased after bolting, with the cork and secretory canals showing strong fluorescence intensity. A total of 34 peaks, mostly pyranocoumarins, were identified in the tissues of Ci Qianhu and Xiong Qianhu. The secretory canals contained the highest variability of coumarins, whereas the secondary xylem contained the least coumarins. Moreover, seven coumarins, especially the pyran- coumarin, decreased after bolting. Generally, both before and after bolting, coumarin level was the highest in the bark, followed by the middle part, and the lowest in the inner part.

CONCLUSION

Thus, it was indicated that the area of secondary xylem increased after bolting, however the coumarin variant and content decreased in the secondary xylem of Qianhu. The result shows that the quality of Qianhu decreases after bolting, which supports the viewpoint that Xiong Qianhu is not suitable for medicinal use.

Anthriscus sylvestris root extract reduces allergic lung inflammation by regulating interferon regulatory factor 4-mediated Th2 cell activation

ETHNOPHARMACOLOGICAL RELEVANCE

Anthriscus sylvestris L. Hoffmann (AS) is a perennial plant that grows in Asia and Eastern Europe. Its dried root is used to treat conditions such as asthma, bronchitis, and cough.

AIM OF THE STUDY

The present study investigated the anti-inflammatory effects of whole AS extract (ASE) on allergic lung inflammation in vitro and in vivo as well as the underlying mechanisms.

MATERIALS AND METHODS

We used an ovalbumin (OVA)-induced asthma mouse model and in vitro primary T helper (Th)2 polarization system. Five groups of 8-week-old female C57BL/6 mice were divided into the following groups: saline control, or OVA-induced allergic asthma with vehicle, ASE (100 or 200 mg/kg), or dexamethasone (5 mg/kg) treatment for 7 days.

RESULTS

ASE attenuated mucus secretion in airway epithelial cells, inflammatory cell infiltration, eosinophilia, and Th2 cytokine levels in bronchoalveolar lavage fluid. Mice administered ASE showed reductions in the activated cluster of differentiation 4⁺ T cell population and GATA-binding protein-3 gene expression in the lung, and diminished Th2 cell differentiation and activation in vitro. Furthermore, ASE-treated mice showed decreased interleukin-6 and interferon regulatory factor (IRF)4 expression, with corresponding reductions in nitric oxide levels in the lungs of asthmatic mice and in stimulated RAW cells.

CONCLUSION

ASE exerts anti-asthmatic effects by inhibiting IRF4 expression and thereby suppressing Th2 cell activation.

Codonopsis lanceolata attenuates allergic lung inflammation by inhibiting Th2 cell activation and augmenting mitochondrial ROS dismutase (SOD2) expression

Allergic asthma is a chronic inflammatory disease induced by the inhalation of allergens, which trigger the activation of T helper type 2 (Th2) cells that release Th2 cytokines. Recently, herbal medicines are being considered a major source of novel agents to treat various diseases. In the present study, we evaluated the anti-asthmatic effects of a Codonopsis lanceolata extract (CLE) and the mechanisms involved in its anti-inflammatory effects. Treatment with CLE reduced infiltration of inflammatory cells, especially eosinophils, and the production of mucus in lung tissues. Levels of Th2 cytokines, such as IL-4, IL-5, and IL-13, and chemokines were also decreased following treatment with CLE. Moreover, Th2 cell proportion in vivo and differentiation in vitro were reduced as evidenced by the decreased expression of GATA3⁺. Furthermore, the expression of superoxide dismutase (SOD)2, a mitochondrial ROS (mROS) scavenger, was increased, which was related to Th2 cell regulation. Interestingly, treatment with CLE increased the number of macrophages in the lungs and enhanced the immune-suppressive property of macrophages. Our findings indicate that CLE has potential as a novel therapeutic agent to inhibit Th2 cell differentiation by regulating mROS scavenging.

Functional characterization and correlation analysis of phenylalanine ammonia-lyase (PAL) in coumarin biosynthesis from Peucedanum praeruptorum Dunn

Coumarins exhibit many biological activities and are the main specialised metabolites of Peucedanum praeruptorum Dunn, an important plant used in traditional Chinese medicine. In preliminary studies, we cloned several genes involved in coumarin biosynthesis in P. praeruptorum, such as 4-coumarate: CoA ligase (4CL), p-coumaroyl CoA 2'-hydroxylase (C2'H), feruloyl CoA 6'-hydroxylase (F6'H) and bergaptol O-methyltransferase (BMT). However, phenylalanine ammonia-lyase (PAL) in P. praeruptorum (PpPAL) has not yet been studied. In the present study, we cloned one novel PpPAL gene. Subsequently, the relationship between gene and compounds was studied using quantitative real-time PCR (qRT-PCR) and High Performance Liquid Chromatography (HPLC) analysis. Then, enzyme function was analyzed with _L-phenylalanine (_L-Phe) as substrate. These experiments showed that the coumarin content could be upregulated by methyl jasmonate (MeJA), UV irradiation and cold, which was consistent with increased expression levels of PpPAL. In addition, correlation analysis indicated that coumarins were partially related to PpPAL. And the recombinant protein could catalyze the conversion of _L-Phe to trans-cinnamic acid (t-CA) with a K_m of 120 ± 33 μM and a K_cat of 117 ± 32 min^-1. Besides, Tyr110, Phe116, Gly117, Ser206, Leu209, Leu259, Tyr354, Arg357, Asn387 and Phe403 were essential for enzymatic activity based on three-dimensional modeling and site-directed mutagenesis experiments. Altogether these results highlight the importance of PpPAL in abiotically induced coumarin biosynthesis and provide further insights regarding the structure-function relationships of this protein.

Identification of Epigenetic Mechanisms Involved in the Anti-Asthmatic Effects of Descurainia sophia Seed Extract Based on a Multi-Omics Approach

Asthma, a heterogeneous disease of the airways, is common around the world, but little is known about the molecular mechanisms underlying the interactions between DNA methylation and gene expression in relation to this disease. The seeds of Descurainia sophia are traditionally used to treat coughs, asthma and edema, but their effects on asthma have not been investigated by multi-omics analysis. We undertook this study to assess the epigenetic effects of ethanol extract of D. sophia seeds (DSE) in an ovalbumin (OVA)-induced mouse model of asthma. We profiled genome-wide DNA methylation by Methyl-seq and characterized the transcriptome by RNA-seq in mouse lung tissue under three conditions: saline control, OVA-induced, and DSE-treated. In total, 1995 differentially methylated regions (DMRs) were identified in association with anti-asthmatic effects, most in promoter and coding regions. Among them, 25 DMRs were negatively correlated with the expression of the corresponding 18 genes. These genes were related to development of the lung, respiratory tube and respiratory system. Our findings provide insights into the anti-asthmatic effects of D. sophia seeds and reveal the epigenetic targets of anti-inflammatory processes in mice.

Antiasthmatic Effects of Sanglong Pingchuan Decoction through Inducing a Balanced Th1/Th2 Immune Response

Objective

To investigate the antiasthmatic effects of Sanglong pingchuan decoction (SLPCD) and to explore its mechanisms of action.

Methods

The serum, bronchoalveolar lavage fluid (BALF), and lung tissues from OVA-induced allergic asthma mice were collected 24 h after the last administration. Lung pathological changes were observed by H&E staining. The inflammatory cells in BALF were counted by flow cytometry. The levels of total IgE in serum and cytokines in BALF were determined by ELISA. The expression levels of cytokine mRNA in lung were assayed by qRT-PCR.

Results

SLPCD significantly inhibited airway inflammation, reduced inflammatory cells in BALF, reduced the levels of total IgE in serum and Th2 cytokines (IL-10 and IL-13) in BALF, and downregulated the mRNA expression levels of Th2 cytokines (IL-4, IL-5, IL-10, and IL-13) in lung of asthmatic mice. However, SLPCD remarkably elevated the level of Th1 cytokine IFN-γ in BALF and upregulated the mRNA expression levels of Th1 cytokines (IL-2 and IFN-γ) in lung of asthmatic mice.

Conclusion

SLPCD could attenuate airway inflammation and alleviate the pathogenesis in asthma mice through inducing a balanced Th1/Th2 response and could act as an effective drug for treatment of asthma.

Peucedanum japonicum extract attenuates allergic airway inflammation by inhibiting Th2 cell activation and production of pro-inflammatory mediators

ETHNOPHARMACOLOGICAL RELEVANCE

The root of Peucedanum japonicum Thunberg is traditionally used to treat coughs, colds, headache and inflammatory diseases in Korea and Japan. Its effects on allergic lung inflammation have not been investigated.

AIM OF THE STUDY

To investigate the anti-asthmatic effects of Peucedanum japonicum extract (PJE) using a murine model of asthma and a lipopolysaccharide (LPS)-stimulated macrophage cell line.

MATERIALS AND METHODS

Mice underwent two rounds of sensitization with ovalbumin 1 week apart followed by four intranasal ovalbumin challenges on days 13-16. The control group received saline only. Two ovalbumin-sensitized groups were orally administered vehicle or PJE (200mg/kg) 5 days a week starting 1 week before the first ovalbumin sensitization. The third group was orally administered the asthma medication Montelukast (10mg/kg) on days 12-16. All animals were sacrificed on day 17. The lungs were assessed for histological features, inflammatory cell infiltration, Th2 cell activation and GATA-binding protein-3 (GATA-3) expression. The bronchoalveolar lavage fluid (BALF) was assessed for type 2 cytokine levels. The effect of PJE on the in vitro Th2 polarization of naïve CD4⁺ splenocytes and the production of pro-inflammatory mediators and cytokines by LPS-stimulated RAW 264.7 cells was evaluated.

RESULTS

PJE treatment inhibited OVA-induced inflammatory cell infiltration, eosinophilia, Th2 activation, and GATA-3 expression in the lung, reduced the interleukin (IL)-5 and IL-13 levels in BALF, down-regulated Th2 activation in vitro, and inhibited the macrophage production of inducible nitric oxide, cyclooxygenase-2, tumor necrosis factor-α, and IL-6.

CONCLUSION

PJE attenuated allergic airway inflammation by inhibiting Th2 cell activation and macrophage production of inflammatory mediators. Peucedanum japonicum may be candidate therapy for allergic lung inflammation.

A framework for the targeted selection of herbs with similar efficacy by exploiting drug repositioning technique and curated biomedical knowledge

ETHNO PHARMACOLOGICAL RELEVANCE

Plants have been the most important natural resources for traditional medicine and for the modern pharmaceutical industry. They have been in demand in regards to finding alternative medicinal herbs with similar efficacy. Due to the very low probability of discovering useful compounds by random screening, researchers have advocated for using targeted selection approaches. Furthermore, because drug repositioning can speed up the process of drug development, an integrated technique that exploits chemical, genetic, and disease information has been recently developed. Building upon these findings, in this paper, we propose a novel framework for the targeted selection of herbs with similar efficacy by exploiting drug repositioning technique and curated modern scientific biomedical knowledge, with the goal of improving the possibility of inferring the traditional empirical ethno-pharmacological knowledge.

MATERIALS AND METHODS

To rank candidate herbs on the basis of similarities against target herb, we proposed and evaluated a framework that is comprised of the following four layers: links, extract, similarity, and model. In the framework, multiple databases are linked to build an herb-compound-protein-disease network which was composed of one tripartite network and two bipartite networks allowing comprehensive and detailed information to be extracted. Further, various similarity scores between herbs are calculated, and then prediction models are trained and tested on the basis of theses similarity features.

RESULTS

The proposed framework has been found to be feasible in terms of link loss. Out of the 50 similarities, the best one enhanced the performance of ranking herbs with similar efficacy by about 120-320% compared with our previous study. Also, the prediction model showed improved performance by about 180-480%. While building the prediction model, we identified the compound information as being the most important knowledge source and structural similarity as the most useful measure.

CONCLUSIONS

In the proposed framework, we took the knowledge of herbal medicine, chemistry, biology, and medicine into consideration to rank herbs with similar efficacy in candidates. The experimental results demonstrated that the performances of framework outperformed the baselines and identified the important knowledge source and useful similarity measure.