Genomics and proteomics of immune modulatory effects of a butanol fraction of echinacea purpurea in human dendritic cells

Evaluation of Echinacea purpurea Extracts as Immunostimulants: Impact on Macrophage Activation

Echinacea purpurea has been traditionally used to strengthen the immune system. Therefore, herein, we investigated the potential of E. purpurea aqueous extracts (AEs) obtained from flowers (F), leaves (L), or roots (R) as an immune booster in human primary monocyte-derived macrophages (hMDMs). Additionally, to identify the main class of compounds (phenolic/carboxylic acids vs. alkylamides) responsible for the bioactivity, the three AEs were fractioned by semi-preparative high-performance liquid chromatography (HPLC). The AEs and the isolated phenolic/carboxylic acidic fractions were not cytotoxic for hMDMs for all tested concentrations, as confirmed by the metabolic activity and DNA content assays. Moreover, AE drastically induced the production of the interleukin (IL)-6 and tumor necrosis factor (TNF)-α, with a minimal effect on IL-1β and prostaglandin E2 (PGE2), supporting their potential for macrophage activation. Interestingly, in the presence of the phenolic/carboxylic acidic fractions, this efficacy considerably decreased, suggesting a complementary effect between compounds. AE also triggered the phosphorylation of the extracellular signal-regulated kinase (ERK) 1/2 and p38 signaling pathways and upregulated the cyclooxygenase (COX)-2 expression in hMDMs. Overall, AE-F was demonstrated to be the most powerful immunostimulant extract that can be related to their higher number in identified bioactive compounds compared to AE-L and AE-R. These results highlight the efficiency of E. purpurea AE to enhance the function of a key cell type of the immune system and their potential as immunostimulant formulations for patients with a compromised immune system due to certain diseases (e.g., acquired immunodeficiencies) and treatments (e.g., chemotherapy).

Immunomodulatory Effect of Phytoactive Compounds on Human Health: A Narrative Review Integrated with Bioinformatics Approach

BACKGROUND

Immunomodulation is the modification of immune responses to control disease progression. While the synthetic immunomodulators have proven efficacy, they are coupled with toxicity and other adverse effects, and hence, the efforts were to identify natural phytochemicals with immunomodulatory potential.

OBJECTIVE

To understand the immunomodulatory properties of various phytochemicals and investigate them in Echinacea species extracts using an in silico approach.

METHODOLOGY

Several scientific database repositories were searched using different keywords: "Phytochemicals," "Alkaloids," "Polyphenols," "Flavonoids," "Lectins," "Glycosides," "Tannins," "Terpenoids," "Sterols," "Immunomodulators," and "Human Immune System" without any language restriction. Additionally, the study specifically investigated the immunomodulatory properties of Echinacea species extracts using gene expression analysis of GSE12259 from NCBI-GEO through the Bioconductor package GEOquery and limma.

RESULTS

A total of 182 studies were comprehensively analyzed to understand immunomodulatory phytochemicals. The in silico analysis highlighted key biological processes (positive regulation of cytokine production, response to tumor necrosis factor) and molecular functions (cytokine receptor binding, receptor-ligand activity, and cytokine activity) among Echinacea species extracts contributing to immune responses. Further, it also indicated the association of various metabolic pathways, i.e., pathways in cancer, cytokine-cytokine receptor interaction, NF-kappa B, PI3K-Akt, TNF, MAPK, and NOD-like receptor signaling pathways, with immune responses. The study revealed various hub targets, including CCL20, CCL4, GCH1, SLC7A11, SOD2, EPB41L3, TNFAIP6, GCLM, EGR1, and FOS.

CONCLUSION

The present study presents a cumulative picture of phytochemicals with therapeutic benefits. Additionally, the study also reported a few novel genes and pathways in Echinacea extracts by re-analyzing GSE 12259 indicating its anti-inflammatory, anti-viral, and immunomodulatory properties.

Echinacea purpurea (L.) Moench Polysaccharide Alleviates DSS-Induced Colitis in Rats by Restoring Th17/Treg Balance and Regulating Intestinal Flora

Echinacea purpurea is popularly used as a food supplement or nutritional supplement for its immune regulatory function against various threats. As one of its promising components, Echinacea purpurea (L.) Moench polysaccharide (EPP) has a wide range of biological activities. To evaluate the effect of EPP as a dietary supplement on ulcerative colitis (UC), this study used sodium dextran sulfate (DSS) to induce a UC model, extracted EPP using the ethanol subsiding method, and then supplemented with EPP by gavage for 7 days. Then, we evaluated the efficacy of EPP on DSS rats in terms of immunity, anti-inflammation, and intestinal flora. The result showed that EPP could alleviate colonic shortening and intestinal injury in rats with DSS-induced colitis, decrease the disease activity index (DAI) score, downregulate serum levels of inflammatory cytokines, and contribute to the restoration of the balance between the T helper cells 17 (Th17) and the regulatory T cells (Treg) in the spleen and mesenteric lymph nodes (MLNs). Meanwhile, EPP could downregulate the expression of Toll-like receptors 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor kappa-B (NF-κB) in colon tissue. In addition, the results of 16SrRNA sequencing showed that EPP also had a regulatory effect on intestinal flora of UC rats. These results indicate that EPP might achieve a beneficial effect on UC rats as a dietary supplement through restoring Th17/Treg balance, inhibiting the TLR4 signaling pathway and regulating intestinal flora, suggesting its possible application as a potential functional food ingredient alleviating UC.

On the Bioactivity of Echinacea purpurea Extracts to Modulate the Production of Inflammatory Mediators

Inflammatory diseases are the focus of several clinical studies, due to limitations and serious side effects of available therapies. Plant-based drugs (e.g., salicylic acid, morphine) have become landmarks in the pharmaceutical field. Therefore, we investigated the immunomodulatory effects of flowers, leaves, and roots from Echinacea purpurea. Ethanolic (EE) and dichloromethanolic extracts (DE) were obtained using the Accelerated Solvent Extractor and aqueous extracts (AE) were prepared under stirring. Their chemical fingerprint was evaluated by liquid chromatography-high resolution mass spectrometry (LC-HRMS). The pro- and anti-inflammatory effects, as well as the reduction in intracellular reactive oxygen and nitrogen species (ROS/RNS), of the different extracts were evaluated using non-stimulated and lipopolysaccharide-stimulated macrophages. Interestingly, AE were able to stimulate macrophages to produce pro-inflammatory cytokines (tumor necrosis factor -TNF-α, interleukin -IL-1β, and IL-6), and to generate ROS/RNS. Conversely, under an inflammatory scenario, all extracts reduced the amount of pro-inflammatory mediators. DE, alkylamides-enriched extracts, showed the strongest anti-inflammatory activity. Moreover, E. purpurea extracts demonstrated generally a more robust anti-inflammatory activity than clinically used anti-inflammatory drugs (dexamethasone, diclofenac, salicylic acid, and celecoxib). Therefore, E. purpurea extracts may be used to develop new effective therapeutic formulations for disorders in which the immune system is either overactive or impaired.

Cellular and Molecular Signaling as Targets for Cancer Vaccine Therapeutics

Plenty of evidence has recently shown that various inflammatory activities at the local tissue, organ, or even the whole body (systemic) level are strongly linked to many life-threatening chronic diseases, most notably various cancers. However, only very limited information is available for making good use of our supporting immune-modulatory therapeutics for the treatment of cancers. This may result from a lack of studies on specific remedies for efficacious control or modulatory suppression of inflammation-related cancerous diseases. Our group and laboratories were fortunate to have initiated and consistently pursued an integrated team-work program project, aimed at investigating selected medicinal herbs and the derived, purified phytochemical compounds. We focused on the study of key and specific immune-signaling mechanisms at the cellular and molecular levels. We were fortunate to obtain a series of fruitful research results. We believe that our key findings reported herein may be helpful for proposing future thematic and integrated research projects that aim to develop future phytochemical drugs against cancers. The mechanisms of the cellular and molecular systems involved in inflammation are becoming increasingly recognized as keystones for the development of future therapeutic approaches for many chronic and cancerous diseases. Recently, the immune checkpoint inhibitors such as antibodies against PD-1 and/or PD-L1 have been shown to be too expensive for general clinical use, and their effects far from optimal, often showing little or no effect or only short-term efficacy. These results point to the need for developing future immune-regulatory or modulatory therapeutics.

A systematic review on the effects of Echinacea supplementation on cytokine levels: Is there a role in COVID-19?

COVID-19 is the respiratory illness caused by the novel coronavirus, SARS-CoV-2. Cytokine storm appears to be a factor in COVID-19 mortality. Echinacea species have been used historically for immune modulation. A previous rapid review suggested that Echinacea supplementation may decrease the levels of pro-inflammatory cytokines involved in cytokine storm. The objective of the present systematic review was to identify all research that has assessed changes in levels of cytokines relevant to cytokine storm in response to administration of Echinacea supplementation. The following databases were searched: Medline (Ovid), AMED (Ovid), CINAHL (EBSCO), EMBASE (Ovid). Title and abstract screening, full text screening, and data extraction were completed in duplicate using a piloted extraction template. Risk of bias assessment was completed. Qualitative analysis was used to assess for trends in cytokine level changes. The search identified 279 unique publications. After full text screening, 105 studies met criteria for inclusion including 13 human studies, 24 animal studies, and 71 in vitro or ex vivo studies. The data suggest that Echinacea supplementation may be associated with a decrease in the pro-inflammatory cytokines IL-6, IL-8, and TNF, as well as an increase in the anti-inflammatory cytokine IL-10. The risk of bias in the included studies was generally high. While there is currently no substantive research on the therapeutic effects of Echinacea in the management of either cytokine storm or COVID-19, the present evidence related to the herb's impact on cytokine levels suggests that further research may be warranted in the form of a clinical trial involving patients with COVID-19.

Echinacea purpurea (L.) Moench treatment of monocytes promotes tonic interferon signaling, increased innate immunity gene expression and DNA repeat hypermethylated silencing of endogenous retroviral sequences

Background

Herbal remedies of Echinacea purpurea tinctures are widely used today to reduce common cold respiratory tract infections.

Methods

Transcriptome, epigenome and kinome profiling allowed a systems biology level characterisation of genomewide immunomodulatory effects of a standardized Echinacea purpurea (L.) Moench extract in THP1 monocytes.

Results

Gene expression and DNA methylation analysis revealed that Echinaforce® treatment triggers antiviral innate immunity pathways, involving tonic IFN signaling, activation of pattern recognition receptors, chemotaxis and immunometabolism. Furthermore, phosphopeptide based kinome activity profiling and pharmacological inhibitor experiments with filgotinib confirm a key role for Janus Kinase (JAK)-1 dependent gene expression changes in innate immune signaling. Finally, Echinaforce® treatment induces DNA hypermethylation at intergenic CpG, long/short interspersed nuclear DNA repeat elements (LINE, SINE) or long termininal DNA repeats (LTR). This changes transcription of flanking endogenous retroviral sequences (HERVs), involved in an evolutionary conserved (epi) genomic protective response against viral infections.

Conclusions

Altogether, our results suggest that Echinaforce® phytochemicals strengthen antiviral innate immunity through tonic IFN regulation of pattern recognition and chemokine gene expression and DNA repeat hypermethylated silencing of HERVs in monocytes. These results suggest that immunomodulation by Echinaforce® treatment holds promise to reduce symptoms and duration of infection episodes of common cold corona viruses (CoV), Severe Acute Respiratory Syndrome (SARS)-CoV, and new occurring strains such as SARS-CoV-2, with strongly impaired interferon (IFN) response and weak innate antiviral defense.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03310-5.

Research and Development of Atractylodes lancea (Thunb) DC. as a Promising Candidate for Cholangiocarcinoma Chemotherapeutics

Treatment and control of cholangiocarcinoma (CCA): the bile duct cancer is limited by the lack of effective chemotherapeutic drugs and alternative drugs are needed, particularly those from natural sources. This article reviews steps of research and development of Atractylodes lancea (Thunb) DC. (AL) as potential candidate for CCA chemotherapy, with adoption of the reverse pharmacology approach. Major steps include (1) reviewing of existing information on its phytochemistry and pharmacological properties, (2) screening of its activities against CCA, (3) standardization of AL, (4) nonclinical studies to evaluate anti-CCA activities, (5) phytochemistry and standardization of AL extract, (6) development of oral pharmaceutical formulation of standardized AL extract, and (7) toxicity testing of oral pharmaceutical formulation of standardized AL extract. Results from a series of our study confirm anti-CCA potential and safety profiles of both the crude extract and the finished product (oral pharmaceutical formulation of the standardized AL extract). Phases I and II clinical trials of the product to confirm tolerability and efficacy in healthy subjects and patients with advanced stage CCA will be carried out soon.

Application of proteomics in the elucidation of chemical-mediated allergic contact dermatitis

Allergic contact dermatitis (ACD) is a widespread hypersensitivity reaction of the skin. The cellular mechanisms underlying its development are complex and involve close interaction of different cell types of the immune system. It is this very complexity which has long prevented straightforward replacement of the corresponding regulatory in vivo tests. Recent efforts have already resulted in the development of several in vitro testing alternatives that address key steps of ACD. Yet identification of suitable biomarkers is still a subject of intense research. Search strategies for the latter encompass transcriptomics, proteomics as well as metabolomics approaches. The scope of this review shall be the application and use of proteomics in the context of ACD. This includes highlighting relevant aspects of the molecular and cellular mechanisms underlying ACD, the exploitation of these mechanisms for testing and biomarkers (e.g., in the context of the OECD's adverse outcome pathway initiative) as well as an outlook on emerging proteome targets, for example during the allergen-induced activation of dendritic cells (DCs).

DNA Microarray-Based Screening and Characterization of Traditional Chinese Medicine

The application of DNA microarray assay (DMA) has entered a new era owing to recent innovations in omics technologies. This review summarizes recent applications of DMA-based gene expression profiling by focusing on the screening and characterizationof traditional Chinese medicine. First, herbs, mushrooms, and dietary plants analyzed by DMA along with their effective components and their biological/physiological effects are summarized and discussed by examining their comprehensive list and a list of representative effective chemicals. Second, the mechanisms of action of traditional Chinese medicine are summarized by examining the genes and pathways responsible for the action, the cell functions involved in the action, and the activities found by DMA (silent estrogens). Third, applications of DMA for traditional Chinese medicine are discussed by examining reported examples and new protocols for its use in quality control. Further innovations in the signaling pathway based evaluation of beneficial effects and the assessment of potential risks of traditional Chinese medicine are expected, just as are observed in other closely related fields, such as the therapeutic, environmental, nutritional, and pharmacological fields.

MVIAeval: a web tool for comprehensively evaluating the performance of a new missing value imputation algorithm

BACKGROUND

Missing value imputation is important for microarray data analyses because microarray data with missing values would significantly degrade the performance of the downstream analyses. Although many microarray missing value imputation algorithms have been developed, an objective and comprehensive performance comparison framework is still lacking. To solve this problem, we previously proposed a framework which can perform a comprehensive performance comparison of different existing algorithms. Also the performance of a new algorithm can be evaluated by our performance comparison framework. However, constructing our framework is not an easy task for the interested researchers. To save researchers' time and efforts, here we present an easy-to-use web tool named MVIAeval (Missing Value Imputation Algorithm evaluator) which implements our performance comparison framework.

RESULTS

MVIAeval provides a user-friendly interface allowing users to upload the R code of their new algorithm and select (i) the test datasets among 20 benchmark microarray (time series and non-time series) datasets, (ii) the compared algorithms among 12 existing algorithms, (iii) the performance indices from three existing ones, (iv) the comprehensive performance scores from two possible choices, and (v) the number of simulation runs. The comprehensive performance comparison results are then generated and shown as both figures and tables.

CONCLUSIONS

MVIAeval is a useful tool for researchers to easily conduct a comprehensive and objective performance evaluation of their newly developed missing value imputation algorithm for microarray data or any data which can be represented as a matrix form (e.g. NGS data or proteomics data). Thus, MVIAeval will greatly expedite the progress in the research of missing value imputation algorithms.

Medicinal plants--prophylactic and therapeutic options for gastrointestinal and respiratory diseases in calves and piglets? A systematic review

BACKGROUND

Gastrointestinal and respiratory diseases in calves and piglets lead to significant economic losses in livestock husbandry. A high morbidity has been reported for diarrhea (calves ≤ 35%; piglets ≤ 50%) and for respiratory diseases (calves ≤ 80%; piglets ≤ 40%). Despite a highly diverse etiology and pathophysiology of these diseases, treatment with antimicrobials is often the first-line therapy. Multi-antimicrobial resistance in pathogens results in international accordance to strengthen the research in novel treatment options. Medicinal plants bear a potential as alternative or additional treatment. Based on the versatile effects of their plant specific multi-component-compositions, medicinal plants can potentially act as 'multi-target drugs'. Regarding the plurality of medicinal plants, the aim of this systematic review was to identify potential medicinal plant species for prevention and treatment of gastrointestinal and respiratory diseases and for modulation of the immune system and inflammation in calves and piglets.

RESULTS

Based on nine initial sources including standard textbooks and European ethnoveterinary studies, a total of 223 medicinal plant species related to the treatment of gastrointestinal and respiratory diseases was identified. A defined search strategy was established using the PRISMA statement to evaluate 30 medicinal plant species starting from 20'000 peer-reviewed articles published in the last 20 years (1994-2014). This strategy led to 418 references (257 in vitro, 84 in vivo and 77 clinical trials, thereof 48 clinical trials in veterinary medicine) to evaluate effects of medicinal plants and their efficacy in detail. The findings indicate that the most promising candidates for gastrointestinal diseases are Allium sativum L., Mentha x piperita L. and Salvia officinalis L.; for diseases of the respiratory tract Echinacea purpurea (L.) MOENCH, Thymus vulgaris L. and Althea officinalis L. were found most promising, and Echinacea purpurea (L.) MOENCH, Camellia sinensis (L.) KUNTZE, Glycyrrhiza glabra L. and Origanum vulgare L. were identified as best candidates for modulation of the immune system and inflammation.

CONCLUSIONS

Several medicinal plants bear a potential for novel treatment strategies for young livestock. There is a need for further research focused on gastrointestinal and respiratory diseases in calves and piglets, and the findings of this review provide a basis on plant selection for future studies.

Optimization of human dendritic cell sample preparation for mass spectrometry-based proteomic studies

Dendritic cells (DCs) are specialized leukocytes that orchestrate the adaptive immune response. Mass spectrometry (MS)-based proteomic study of these cells presents technical challenges, especially when the DCs are human in origin due to the paucity of available biological material. Here, to maximize MS coverage of the global human DC proteome, different cell disruption methods, lysis conditions, protein precipitation, and protein pellet solubilization and denaturation methods were compared. Mechanical disruption of DC cell pellets under cryogenic conditions, coupled with the use of RIPA (radioimmunoprecipitation assay) buffer, was shown to be the method of choice based on total protein extraction and on the solubilization and identification of nuclear proteins. Precipitation by acetone was found to be more efficient than that by 10% trichloroacetic acid (TCA)/acetone, allowing in excess of 28% more protein identifications. Although being an effective strategy to eliminate the detergent residue, the acetone wash step caused a loss of protein identifications. However, this potential drawback was overcome by adding 1% sodium deoxycholate into the dissolution buffer, which enhanced both solubility of the precipitated proteins and digestion efficiency. This in turn resulted in 6 to 11% more distinct peptides and 14 to 19% more total proteins identified than using 0.5M triethylammonium bicarbonate alone, with the greatest increase (34%) for hydrophobic proteins.

Xueshuan Xinmaining Tablet Treats Blood Stasis through Regulating the Expression of F13a1, Car1, and Tbxa2r

Xueshuan Xinmaining Tablet (XXT), the Chinese formula, has long been administered in clinical practice for the treatment of cerebral thrombosis and coronary heart disease. In this study, we aimed to study the effect and the molecular mechanism of activating blood circulation and removing blood stasis. Rat models of cold coagulation blood stasis were induced with ice-water bath and epinephrine to assess the amelioration of blood stasis by XXT. Microarray technique was used to identify gene expression from the model and XXT-treated rats. In addition, Quantitative Real-Time PCR (qPCR) was performed to verify the microarray results. The results showed that XXT had a good therapeutic effect on blood stasis by reducing the whole blood viscosity (WBV), plasma viscosity (PV), increasing PT, APTT and TT, and by inhibiting platelet aggregation. Genes were differentially expressed in rats among the model group and the XXT-pretreated groups. XXT ameliorated blood stasis by regulating the expressions of F13a1, Car1, and Tbxa2r.

[New approaches to elucidate the activities of botanical multi-component mixtures]

Although the major activities of traditional remedies have mostly been known since ancient times, their molecular mechanisms of action have usually not been investigated in much detail. The pharmaceutically relevant activities of botanical therapeutics frequently result from additive or synergistic effects of a multitude of components. Several studies have been published that analyze the effects of complex preparations on selected in vitro model cell systems by using gene expression analysis. Herein, the examples referred to include transcriptional studies with extracts from Ginkgo biloba and Echinacea as well as the Tibetan Formula Padma 28. Transcriptional profiles can be used to deduce key molecules and pathways affected upon treatment. Differentially expressed gene sets can further be integrated with information derived from interaction databases, thus giving a more comprehensive view of activated biological processes. Transcriptomics, by using microarray technology, is used as a tool in different fields of natural product research, ranging from activity monitoring to toxicity profiling.

The Saccharomyces cerevisiae transcriptome as a mirror of phytochemical variation in complex extracts of Equisetum arvense from America, China, Europe and India

BACKGROUND

Pattern-oriented chemical profiling is increasingly being used to characterize the phytochemical composition of herbal medicines for quality control purposes. Ideally, a fingerprint of the biological effects should complement the chemical fingerprint. For ethical and practical reasons it is not possible to test each herbal extract in laboratory animals or humans. What is needed is a test system consisting of an organism with relevant biology and complexity that can serve as a surrogate in vitro system. The purpose of this study was to test the hypothesis that the Saccharomyces cerevisiae transcriptome might be used as an indicator of phytochemical variation of closely-related yet distinctly different extracts prepared from a single species of a phytogeographically widely distributed medicinal plant. We combined phytochemical profiling using chromatographic methods (HPTLC, HPLC-PDA-MS/MS) and gene expression studies using Affymetrix Yeast 2.0 gene chip with principal component analysis and k-nearest neighbor clustering analysis to test this hypothesis using extracts prepared from the phytogeographically widely distributed medicinal plant Equisetum arvense as a test case.

RESULTS

We found that the Equisetum arvense extracts exhibited qualitative and quantitative differences in their phytochemical composition grouped along their phytogeographical origin. Exposure of yeast to the extracts led to changes in gene expression that reflected both the similarities and differences in the phytochemical composition of the extracts. The Equisetum arvense extracts elicited changes in the expression of genes involved in mRNA translation, drug transport, metabolism of energy reserves, phospholipid metabolism, and the cellular stress response.

CONCLUSIONS

Our data show that functional genomics in S. cerevisiae may be developed as a sensitive bioassay for the scientific investigation of the interplay between phytochemical composition and transcriptional effects of complex mixtures of chemical compounds. S. cerevisiae transcriptomics may also be developed for testing of mixtures of conventional drugs ("polypills") to discover novel antagonistic or synergistic effects of those drug combinations.

The Phytochemical Shikonin Stimulates Epithelial-Mesenchymal Transition (EMT) in Skin Wound Healing

Although various pharmacological activities of the shikonins have been documented, understanding the hierarchical regulation of these diverse bioactivities at the genome level is unsubstantiated. In this study, through cross examination between transcriptome and microRNA array analyses, we predicted that topical treatment of shikonin in vivo affects epithelial-mesenchymal transition (EMT) and the expression of related microRNAs, including 200a, 200b, 200c, 141, 205, and 429 microRNAs, in mouse skin tissues. In situ immunohistological analyses further demonstrated that specific EMT regulatory molecules are enhanced in shikonin-treated epidermal tissues. RT-PCR analyses subsequently confirmed that shikonin treatment downregulated expression of microRNA-205 and other members of the 200 family microRNAs. Further, expression of two RNA targets of the 200 family microRNAs in EMT regulation, Sip1 (Zeb2) and Tcf8 (Zeb1), was consistently upregulated by shikonin treatment. Enhancement of these EMT activities was also detected in shikonin-treated wounds, which repaired faster than controls. These results suggest that topical treatment with shikonin can confer a potent stimulatory effect on EMT and suppress the expression of the associated microRNAs in skin wound healing. Collectively, these cellular and molecular data provide further evidence in support of our previous findings on the specific pharmacological effects of shikonin in wound healing and immune modulation.

A proteomic insight into the effects of the immunomodulatory hydroxynaphthoquinone lapachol on activated macrophages

We report the effect of an immunomodulatory and anti-mycobacterial naphthoquinone, lapachol, on the bi-dimensional patterns of protein expression of toll-like receptor 2 (TLR2)-agonised and IFN-γ-treated THP-1 macrophages. This non-hypothesis driven proteomic analysis intends to shed light on the cellular functions lapachol may be affecting. Proteins of both cytosol and membrane fractions were analysed. After quantification of the protein spots, the protein levels corresponding to macrophages activated in the absence or presence of lapachol were compared. A number of proteins were identified, the levels of which were appreciably and significantly increased or decreased as a result of the action of lapachol on the activated macrophages: cofilin-1, fascin, plastin-2, glucose-6-P-dehydrogenase, adenylyl cyclase-associated protein 1, pyruvate kinase, sentrin-specific protease 6, cathepsin B, cathepsin D, cytosolic aminopeptidase, proteasome β type-4 protease, tryptophan-tRNA ligase, DnaJ homolog and protein disulphide isomerase. Altogether, the comparative analysis performed indicates that lapachol could be hypothetically causing an impairment of cell migration and/or phagocytic capacity, an increase in NADPH availability, a decrease in pyruvate concentration, protection from proteosomal protein degradation, a decrease in lysosomal protein degradation, an impairment of cytosolic peptide generation, and an interference with NOS2 activation and grp78 function. The present proteomic results suggest issues that should be experimentally addressed ex- and in-vivo, to establish more accurately the potential of lapachol as an anti-infective drug. This study also constitutes a model for the pre-in-vivo evaluation of drug actions.

Developing Phytocompounds from Medicinal Plants as Immunomodulators

Imbalance or malfunction of the immune systems is associated with a range of chronic diseases including autoimmune diseases, allergies, cancers and others. Various innate and adaptive immune cells that are integrated in this complex networking system may represent promising targets for developing immunotherapeutics for treating specific immune diseases. A spectrum of phytochemicals have been isolated, characterized and modified for development and use as prevention or treatment of human diseases. Many cytotoxic drugs and antibiotics have been developed from phytocompounds, but the application of traditional or new medicinal plants for use as immunomodulators in treating immune diseases is still relatively limited. In this review, a selected group of medicinal herbs, their derived crude or fractionated phytoextracts and the specific phytochemicals/phytocompounds isolated from them, as well as categorized phytocompound groups with specific chemical structures are discussed in terms of their immunomodulatory bioactivities. We also assess their potential for future development as immunomodulatory or inflammation-regulatory therapeutics or agents. New experimental approaches for evaluating the immunomodulatory activities of candidate phytomedicines are also discussed.

Is PPARG the key gene in diabetic retinopathy?

Diabetic retinopathy, a microvascular complication of diabetes mellitus, is major cause of non-inherited blindness among adults. Although diabetic retinopathy is a common complication of diabetes, we still know little about the underlying molecular mechanisms. In recent years, complex connections between important molecules and pathways in the onset and progression of diabetic retinopathy, such as advanced glycation end products, oxidative stress and inflammation, have been elucidated. Biochemical, genetic and functional studies strongly indicate peroxisome proliferator-activated receptor-γ (PPARγ), a pleiotropic transcription factor, as a primary target in the treatment of diabetic retinopathy. In this issue, Song et al. detail the role of PPARγ in diabetic retinopathy-related disorders, illustrating PPARγ-mediated inhibition of diabetes-induced leukostasis and leakage, and its beneficial role in modulating inflammation, angiogenesis and apoptosis in retinal and endothelial cells. Moreover, they describe alternative treatments for diabetic retinopathy, such as plant-derived PPARγ ligands, proposing their use - in combination with standard therapies - for modulation of diabetic retinopathy.

Topical application of marine briarane-type diterpenes effectively inhibits 12-O-tetradecanoylphorbol-13-acetate-induced inflammation and dermatitis in murine skin

Background

Skin is the largest organ in the body, and is directly exposed to extrinsic assaults. As such, the skin plays a central role in host defense and the cutaneous immune system is able to elicit specific local inflammatory and systemic immune responses against harmful stimuli. 12-O-tetradecanoylphorbol-13-acetate (TPA) can stimulate acute and chronic inflammation and tumor promotion in skin. TPA-induced dermatitis is thus a useful in vivo pharmacological platform for drug discovery. In this study, the inhibitory effect of briarane-type diterpenes (BrDs) from marine coral Briareum excavatum on TPA-induced dermatitis and dendritic cell (DC) function was explored.

Methods

Evans blue dye exudation was used to determine vascular permeability. H&E-stained skin section was used to determine the formation of edema in mouse abdominal skin. We also used immunohistochemistry staining and western blot assays to evaluate the activation of specific inflammation makers and key mediators of signaling pathway in the mouse skin. Furthermore, mouse bone marrow DCs were used to determine the relationship between the chemical structure of BrDs and their regulation of DC function.

Results

BrD1 remarkably suppressed TPA-induced vascular permeability and edema in skin. At the biochemical level, BrD1 inhibited TPA-induced expression of cyclooxygenase-2, inducible nitric oxide synthase and matrix metalloproteinase-9, the key indicators of cutaneous inflammation. This inhibition was apparently mediated by interference with the Akt/NF-κB-mediated signaling network. BrD1 also inhibited TNF-α and IL-6 expression in LPS-stimulated BMDCs. The 8, 17-epoxide of BrDs played a crucial role in the inhibition of IL-6 expression, and replacement of the C-12 hydroxyl group with longer esters in BrDs gradually decreased this inhibitory activity.

Conclusions

Our results suggest that BrDs warrant further investigation as natural immunomodulatory agents for control of inflammatory skin diseases.

Applications of the phytomedicine Echinacea purpurea (Purple Coneflower) in infectious diseases

Extracts of Echinacea purpurea (EP, purple coneflower) have been used traditionally in North America for the treatment of various types of infections and wounds, and they have become very popular herbal medicines globally. Recent studies have revealed that certain standardized preparations contain potent and selective antiviral and antimicrobial activities. In addition, they display multiple immune-modulatory activities, comprising stimulation of certain immune functions such as phagocytic activity of macrophages and suppression of the proinflammatory responses of epithelial cells to viruses and bacteria, which are manifested as alterations in secretion of various cytokines and chemokines. These immune modulations result from upregulation or downregulation of the relevant genes and their transcription factors. All these bioactivities can be demonstrated at noncytotoxic concentrations of extract and appear to be due to multiple components rather than the individual chemical compounds that characterize Echinacea extracts. Potential applications of the bioactive extracts may go beyond their traditional uses.

A quantitative proteomic approach for detecting protein profiles of activated human myeloid dendritic cells

Dendritic cells (DC) direct the magnitude, polarity and effector function of the adaptive immune response. DC express toll-like receptors (TLR), antigen capturing and processing machinery, and costimulatory molecules, which facilitate innate sensing and T cell activation. Once activated, DC can efficiently migrate to lymphoid tissue and prime T cell responses. Therefore, DC play an integral role as mediators of the immune response to multiple pathogens. Elucidating the molecular mechanisms involved in DC activation is therefore central in gaining an understanding of host response to infection. Unfortunately, technical constraints have limited system-wide 'omic' analysis of human DC subsets collected ex vivo. Here we have applied novel proteomic approaches to human myeloid dendritic cells (mDCs) purified from 100 mL of peripheral blood to characterize specific molecular networks of cell activation at the individual patient level, and have successfully quantified over 700 proteins from individual samples containing as little as 200,000 mDCs. The proteomic and network readouts after ex vivo stimulation of mDCs with TLR3 agonists are measured and verified using flow cytometry.

Echinacea—A Source of Potent Antivirals for Respiratory Virus Infections

Extracts of Echinacea species have been used traditionally in North America for the control of symptoms of colds, influenza, and other diseases, and some of them have become very popular as “herbal medicines”. Recent studies have revealed that preparations derived from certain species and plant parts, but not all of them, possess potent antiviral activities, at non-cytotoxic concentrations, particularly against membrane-containing viruses. Thus all strains of human and avian influenza viruses tested (including a Tamiflu-resistant strain), as well as herpes simplex virus, respiratory syncytial virus, and rhinoviruses, were very sensitive to a standardized Echinacea purpurea preparation. In mechanistic studies the influenza virus-specific hemagglutinin and neuraminidase were inhibited. In addition some extracts displayed anti-inflammatory activity in virus-infected cells, and numerous other effects on the expression of cellular genes. Multiple components, either discrete compounds or mixtures, appeared to be responsible for the various antiviral activities.

Discovery of molecular mechanisms of traditional Chinese medicinal formula Si-Wu-Tang using gene expression microarray and connectivity map

To pursue a systematic approach to discovery of mechanisms of action of traditional Chinese medicine (TCM), we used microarrays, bioinformatics and the “Connectivity Map” (CMAP) to examine TCM-induced changes in gene expression. We demonstrated that this approach can be used to elucidate new molecular targets using a model TCM herbal formula Si-Wu-Tang (SWT) which is widely used for women's health. The human breast cancer MCF-7 cells treated with 0.1 µM estradiol or 2.56 mg/ml of SWT showed dramatic gene expression changes, while no significant change was detected for ferulic acid, a known bioactive compound of SWT. Pathway analysis using differentially expressed genes related to the treatment effect identified that expression of genes in the nuclear factor erythroid 2-related factor 2 (Nrf2) cytoprotective pathway was most significantly affected by SWT, but not by estradiol or ferulic acid. The Nrf2-regulated genes HMOX1, GCLC, GCLM, SLC7A11 and NQO1 were upreguated by SWT in a dose-dependent manner, which was validated by real-time RT-PCR. Consistently, treatment with SWT and its four herbal ingredients resulted in an increased antioxidant response element (ARE)-luciferase reporter activity in MCF-7 and HEK293 cells. Furthermore, the gene expression profile of differentially expressed genes related to SWT treatment was used to compare with those of 1,309 compounds in the CMAP database. The CMAP profiles of estradiol-treated MCF-7 cells showed an excellent match with SWT treatment, consistent with SWT's widely claimed use for women's diseases and indicating a phytoestrogenic effect. The CMAP profiles of chemopreventive agents withaferin A and resveratrol also showed high similarity to the profiles of SWT. This study identified SWT as an Nrf2 activator and phytoestrogen, suggesting its use as a nontoxic chemopreventive agent, and demonstrated the feasibility of combining microarray gene expression profiling with CMAP mining to discover mechanisms of actions and to identify new health benefits of TCMs.

Echinacea-induced cytosolic Ca2+ elevation in HEK293

Background

With a traditional medical use for treatment of various ailments, herbal preparations of Echinacea are now popularly used to improve immune responses. One likely mode of action is that alkamides from Echinacea bind to cannabinoid type 2 (CB2) receptors and induce a transient increase in intracellular Ca²⁺. Here, we show that unidentified compounds from Echinacea purpurea induce cytosolic Ca²⁺ elevation in non-immune-related cells, which lack CB2 receptors and that the Ca²⁺ elevation is not influenced by alkamides.

Methods

A non-immune human cell line, HEK293, was chosen to evaluate E. purpurea root extracts and constituents as potential regulators of intracellular Ca²⁺ levels. Changes in cytosolic Ca²⁺ levels were monitored and visualized by intracellular calcium imaging. U73122, a phospholipase C inhibitor, and 2-aminoethoxydiphenyl borate (2-APB), an antagonist of inositol-1,4,5-trisphosphate (IP₃) receptor, were tested to determine the mechanism of this Ca²⁺ signaling pathway. E. purpurea root ethanol extracts were fractionated by preparative HPLC, screened for bioactivity on HEK293 cells and by GC-MS for potential constituent(s) responsible for this bioactivity.

Results

A rapid transient increase in cytosolic Ca²⁺ levels occurs when E. purpurea extracts are applied to HEK293 cells. These stimulatory effects are phospholipase C and IP₃ receptor dependent. Echinacea-evoked responses could not be blocked by SR 144528, a specific CB2 receptor antagonist, indicating that CB2 is not involved. Ca²⁺ elevation is sustained after the Echinacea-induced Ca²⁺ release from intracellular Ca²⁺ stores; this longer-term effect is abolished by 2-APB, indicating a possible store operated calcium entry involvement. Of 28 HPLC fractions from E. purpurea root extracts, six induce cytosolic Ca²⁺ increase. Interestingly, GC-MS analysis of these fractions, as well as treatment of HEK293 cells with known individual and combined chemicals, indicates the components thought to be responsible for the major immunomodulatory bioactivity of Echinacea do not explain the observed Ca²⁺ response. Rather, lipophilic constituents of unknown structures are associated with this bioactivity.

Conclusions

Our data indicate that as yet unidentified constituents from Echinacea stimulate an IP₃ receptor and phospholipase C mediation of cytosolic Ca²⁺ levels in non-immune mammalian cells. This pathway is distinct from that induced in immune associated cells via the CB2 receptor.

Stimulatory effect of Echinacea purpurea extract on the trafficking activity of mouse dendritic cells: revealed by genomic and proteomic analyses

BACKGROUND

Several Echinacea species have been used as nutraceuticals or botanical drugs for "immunostimulation", but scientific evidence supporting their therapeutic use is still controversial. In this study, a phytocompound mixture extracted from the butanol fraction (BF) of a stem and leaf (S+L) extract of E. purpurea ([BF/S+L/Ep]) containing stringently defined bioactive phytocompounds was obtained using standardized and published procedures. The transcriptomic and proteomic effects of this phytoextract on mouse bone marrow-derived dendritic cells (BMDCs) were analyzed using primary cultures.

RESULTS

Treatment of BMDCs with [BF/S+L/Ep] did not significantly influence the phenotypic maturation activity of dendritic cells (DCs). Affymetrix DNA microarray and bioinformatics analyses of genes differentially expressed in DCs treated with [BF/S+L/Ep] for 4 or 12 h revealed that the majority of responsive genes were related to cell adhesion or motility (Cdh10, Itga6, Cdh1, Gja1 and Mmp8), or were chemokines (Cxcl2, Cxcl7) or signaling molecules (Nrxn1, Pkce and Acss1). TRANSPATH database analyses of gene expression and related signaling pathways in treated-DCs predicted the JNK, PP2C-α, AKT, ERK1/2 or MAPKAPK pathways as the putative targets of [BF/S+L/Ep]. In parallel, proteomic analysis showed that the expressions of metabolic-, cytoskeleton- or NF-κB signaling-related proteins were regulated by treatment with [BF/S+L/Ep]. In vitro flow cytometry analysis of chemotaxis-related receptors and in vivo cell trafficking assay further showed that DCs treated with [BF/S+L/Ep] were able to migrate more effectively to peripheral lymph node and spleen tissues than DCs treated as control groups.

CONCLUSION

Results from this study suggest that [BF/S+L/Ep] modulates DC mobility and related cellular physiology in the mouse immune system. Moreover, the signaling networks and molecules highlighted here are potential targets for nutritional or clinical application of Echinacea or other candidate medicinal plants.

Differential functional genomic effects of anti-inflammatory phytocompounds on immune signaling

BACKGROUND

Functional comparative genomic analysis of the cellular immunological effects of different anti-inflammatory phytocompounds is considered as a helpful approach to distinguish the complex and specific bioactivities of candidate phytomedicines. Using LPS-stimulated THP-1 monocytes, we characterize here the immunomodulatory activities of three single phytocompounds (emodin, shikonin, and cytopiloyne) and a defined phytocompound mixture extracted from Echinacea plant (BF/S+L/Ep) by focused DNA microarray analysis of selected immune-related genes.

RESULTS

Shikonin and emodin significantly inhibited the early expression (within 0.5 h) of approximately 50 genes, notably cytokines TNF-α, IL-1β and IL-4, chemokines CCL4 and CCL8, and inflammatory modulators NFATC3 and PTGS2. In contrast, neither cytopiloyne nor BF/S+L/Ep inhibited the early expression of these 50 genes, but rather inhibited most late-stage expression (~12 h) of another immune gene subset. TRANSPATH database key node analysis identified the extracellular signal-regulated kinase (ERK) 1/2 activation pathway as the putative target of BF/S+L/Ep and cytopiloyne. Western blot confirmed that delayed inactivation of the ERK pathway was indeed demonstrable for these two preparations during the mid-stage (1 to 4 h) of LPS stimulation. We further identified ubiquitin pathway regulators, E6-AP and Rad23A, as possible key regulators for emodin and shikonin, respectively.

CONCLUSION

The current focused DNA microarray approach rapidly identified important subgenomic differences in the pattern of immune cell-related gene expression in response to specific anti-inflammatory phytocompounds. These molecular targets and deduced networks may be employed as a guide for classifying, monitoring and manipulating the molecular and immunological specificities of different anti-inflammatory phytocompounds in key immune cell systems and for potential pharmacological application.

Enrichment of Echinacea angustifolia with Bauer alkylamide 11 and Bauer ketone 23 increased anti-inflammatory potential through interference with cox-2 enzyme activity

Bauer alkylamide 11 and Bauer ketone 23 were previously found to be partially responsible for Echinacea angustifolia anti-inflammatory properties. This study further tested their importance using the inhibition of prostaglandin E(2) (PGE(2)) and nitric oxide (NO) production by RAW264.7 mouse macrophages in the absence and presence of lipopolysaccharide (LPS) and E. angustifolia extracts, phytochemical enriched fractions, or pure synthesized standards. Molecular targets were probed using microarray, qRT-PCR, Western blot, and enzyme assays. Fractions with these phytochemicals were more potent inhibitors of LPS-induced PGE(2) production than E. angustifolia extracts. Microarray did not detect changes in transcripts with phytochemical treatments; however, qRT-PCR showed a decrease in TNF-alpha and an increase of iNOS transcripts. LPS-induced COX-2 protein was increased by an E. angustifolia fraction containing Bauer ketone 23 and by pure phytochemical. COX-2 activity was decreased with all treatments. The phytochemical inhibition of PGE(2) production by Echinacea may be due to the direct targeting of COX-2 enzyme.

Echinacea purpurea extracts modulate murine dendritic cell fate and function

Echinacea is a top-selling herbal remedy that purportedly acts as an immunostimulant. However, the specific immunomodulatory effects of Echinacea remain to be elucidated. We focused on defining the effects of Echinacea purpurea extracts in dendritic cells (DCs), which generate innate and adaptive immune responses. We hypothesized that E. purpurea extracts would enhance murine bone marrow-derived DC (BMDC) activation leading to increased immune responses. The fate and function of DCs from C57Bl/6 mice was evaluated following 48h exposure to E. purpurea root and leaf extracts. Flow cytometry revealed that the polysaccharide-rich root extract increased the expression of MHC class II, CD86, and CD54 surface biomarkers whereas the alkylamide-rich leaf extract inhibited expression of these molecules. Production of IL-6 and TNF-alpha increased in a concentration-dependent manner with exposure to the root, but not leaf, extract. In contrast, the leaf but not root extract inhibited the enzymatic activity of cyclooxygenase-2. While both extracts decreased the uptake of ovalbumin by BMDCs, the leaf but not root extract inhibited the antigen-specific activation of naïve CD4(+) T cells from OT II/Thy1.1 mice. Collectively, these results suggest that E. purpurea can be immunostimulatory, immunosuppressive, and/or anti-inflammatory depending on the portion of the plant and extraction method.

Transdermal behaviour of the N-alkylamide spilanthol (affinin) from Spilanthes acmella (Compositae) extracts

AIM OF THE STUDY

N-Alkylamides are a large group of bioactive molecules found in several plants from the genera Echinacea, Xanthoxylum and Spilanthes. Extracts and formulations derived from these plants are not only orally used, but also applied on the skin as well. However, there is currently no specific information available about the intrinsic local pharmacokinetics of N-alkylamides after topical application on human skin, questioning the role of this mode of administration. The present study investigates the transdermal behaviour of spilanthol, a prominent N-alkylamide.

MATERIALS AND METHODS

Two pharmaceutically accepted dose solutions (ethanol and propylene glycol based aqueous donor vehicles), combined with three different receptor fluids (PBS, PBS+0.5% HPbetaCD, EtOH/H(2)O (30:70, v/v)), were applied on split-thickness human skin in a Franz diffusion cell (FDC) system. Fundamental permeation characteristics of spilanthol in a solvent-independent way (100% aqueous dose solution) were also obtained using an extrapolation approach with different organic solvent/H(2)O ratios.

RESULTS AND CONCLUSIONS

We demonstrated for the first time that spilanthol permeates the skin. The following aqueous-extrapolated primary transdermal parameters were obtained (mean+/-SEM): K(p,aq)=3.31 (+/-0.29)x10(-3)cm/h, D(m,aq)=1.86 (+/-0.09)x10(-4)cm(2)/h and K(m,aq)=7.28 (+/-1.59)x10(-1). Partitioning (K(m)) was strongly dependent on the donor solution composition, while diffusion (D(m)) was mainly influenced by the receptor fluid composition.

Assessment of herbal medicinal products: challenges, and opportunities to increase the knowledge base for safety assessment

Although herbal medicinal products (HMP) have been perceived by the public as relatively low risk, there has been more recognition of the potential risks associated with this type of product as the use of HMPs increases. Potential harm can occur via inherent toxicity of herbs, as well as from contamination, adulteration, plant misidentification, and interactions with other herbal products or pharmaceutical drugs. Regulatory safety assessment for HMPs relies on both the assessment of cases of adverse reactions and the review of published toxicity information. However, the conduct of such an integrated investigation has many challenges in terms of the quantity and quality of information. Adverse reactions are under-reported, product quality may be less than ideal, herbs have a complex composition and there is lack of information on the toxicity of medicinal herbs or their constituents. Nevertheless, opportunities exist to capitalise on newer information to increase the current body of scientific evidence. Novel sources of information are reviewed, such as the use of poison control data to augment adverse reaction information from national pharmacovigilance databases, and the use of more recent toxicological assessment techniques such as predictive toxicology and omics. The integration of all available information can reduce the uncertainty in decision making with respect to herbal medicinal products. The example of Aristolochia and aristolochic acids is used to highlight the challenges related to safety assessment, and the opportunities that exist to more accurately elucidate the toxicity of herbal medicines.

Understanding dendritic cell biology and its role in immunological disorders through proteomic profiling

Dendritic cells (DC) have always been present on the bright spot of immune research. They have been extensively studied for the last 35 years, and much is known about their different phenotypes, stimulatory capacity, and role in the immune system. During the last 15 years, great attention has been given to studies on global gene and protein expression profiles during the differentiation and maturation processes of these cells. It is well understood that studying the proteome, together with information on the role of protein post-translational modifications (PTM), will reveal the real dynamics of a living cell. The rapid increase of proteomic studies during the last decade describing the differentiation and maturation process in DCs, as well as modifications brought by the use of different compounds that either increase or decrease their immunogenicity, reflects the importance of understanding the molecular processes behind the functional properties of these cells. In the present review, we will give an overview of proteomic studies focusing on DCs. Thereby we will concentrate on the importance of these studies in understanding DC behavior from a molecular point of view and how these findings have aided in understanding the differences in functional properties of these cells.