The triterpenoid lupeol attenuates allergic airway inflammation in a murine model

A Triterpenoid Lupeol as an Antioxidant and Anti-Neuroinflammatory Agent: Impacts on Oxidative Stress in Alzheimer's Disease

Alzheimer's disease (AD) is the most common neurodegenerative disease illustrated by neuronal dysfunctions, leading to memory weaknesses and personality changes mostly in the aged population worldwide. The exact cause of AD is unclear, but numerous studies have addressed the involvement of oxidative stress (OS), induced by reactive oxygen species (ROS), to be one of the leading causes in developing AD. OS dysregulates the cellular homeostasis, causing abnormal protein and lipid metabolism. Nutrition plays a pivotal role in modulating the antioxidant system and decreases the neuronal ROS level, thus playing an important therapeutic role in neurodegenerative diseases, especially in AD. Hence, medicinal herbs and their extracts have received global attention as a commercial source of antioxidants Lupeol. Lupeol is a pentacyclic triterpenoid and has many biological functions. It is available in fruits, vegetables, and medicinal plants. It has shown effective antioxidant and anti-inflammatory properties, and higher blood-brain barrier permeability. Also, the binding and inhibitory potentials of Lupeol have been investigated and proved to be effective against certain receptor proteins and enzymes in AD studies by computational molecular docking approaches. Therefore, AD-related research has gained interest in investigating the therapeutic effects of Lupeol. However, despite its beneficial effects in AD, there is still a lack of research in Lupeol. Hence, we compiled in this analysis all preclinical research that looked at Lupeol as an antioxidant and anti-inflammatory agent for AD.

Lupeol alleviates atopic dermatitis-like skin inflammation in 2,4-dinitrochlorobenzene/Dermatophagoides farinae extract-induced mice

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects from children to adults widely, presenting symptoms such as pruritus, erythema, scaling, and dryness. Lupeol, a pentacyclic triterpenoid, has anti-inflammatory and antimicrobial activities. Based on these properties, the therapeutic effects of lupeol on skin disorders have been actively studied. In the present study, we aimed to determine the effectiveness of lupeol on AD.

METHODS

We utilized tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated keratinocytes and 2, 4-dinitrochlorobenzene/Dermatophagoides farinae extract (DFE)-induced AD mice to confirm the action.

RESULTS

Lupeol inhibited TNF-α/IFN-γ-stimulated keratinocytes activation by reducing the expressions of pro-inflammatory cytokines and chemokines which are mediated by the activation of signaling molecules such as signal transducer and activator of transcription 1, mitogen-activated protein kinases (p38 and ERK), and nuclear factor-κB. Oral administration of lupeol suppressed epidermal and dermal thickening and immune cell infiltration in ear tissue. Immunoglobulin (Ig) E (total and DFE-specific) and IgG2a levels in serum were also reduced by lupeol. The gene expression and protein secretion of T helper (Th) 2 cytokines, Th1 cytokines, and pro-inflammatory cytokine in ear tissue were decreased by lupeol.

CONCLUSIONS

These results suggest that lupeol has inhibitory effects on AD-related responses. Therefore, lupeol could be a promising therapeutic agent for AD.

Antiallergic Effects of Callerya atropurpurea Extract In Vitro and in an In Vivo Atopic Dermatitis Model

(1) Background: Callerya atropurpurea is found in Laos, Thailand, and Vietnam. Although the anti-inflammatory action of C. atropurpurea has been investigated, the functions of this plant in allergic responses are not understood. Here, we explored the antiallergic mechanism of C. atropurpurea ethanol extract (Ca-EE) using in vitro assays and an in vivo atopic model. (2) Methods: The constituents of Ca-EE were analyzed using GC/MS. Inhibition of lipoxygenase and β-hexosaminidase activity was examined, and the expression of inflammatory genes was measured by quantitative real-time PCR. The regulatory roles of Ca-EE in IgE/FcεRI signaling were examined by Western blotting. The DNCB-induced atopic dermatitis mouse model was performed with histological analysis. (3) Results: Ca-EE comprised cis-raphasatin, lupeol, some sugars, and fatty acids. In RBL-2H3 cells, treatment with Ca-EE significantly reduced the activities of lipoxygenase and β-hexosaminidase, as well as cytokine gene expression. IgE-mediated signaling was downregulated by blocking Lyn kinases. Moreover, Ca-EE effectively inhibited allergic symptoms in the DNCB-induced atopic dermatitis model without toxicity. (4) Conclusions: Ca-EE displayed antiallergic activities through regulating IgE/Lyn signaling in RBL-2H3 cells and a contact dermatitis model. These results indicate that Ca-EE could be effective for allergic disease treatment.

Identification of Molecular Markers Related to Immune Infiltration in Patients with Severe Asthma: A Comprehensive Bioinformatics Analysis Based on the Human Bronchial Epithelial Transcriptome

Background. Severe asthma (SA), a heterogeneous inflammatory disease characterized by immune cell infiltration, is particularly difficult to treat and manage. The airway epithelium is an important tissue in regulating innate and adaptive immunity, and targeting airway epithelial cell may contribute to improving the efficacy of asthma therapy. Methods. Bioinformatics methods were utilized to identify the hub genes and signaling pathways involved in SA. Experiments were performed to determine whether these hub genes and signaling pathways were affected by the differences in immune cell infiltration. Results. The weighted gene coexpression network analysis identified 14 coexpression modules, among which the blue and salmon modules exhibited the strongest associations with SA. The blue module was mainly enriched in actomyosin structure organization and was associated with regulating stem cell pluripotency signaling pathways. The salmon module was mainly involved in cornification, skin development, and glycosphingolipid biosynthesis-lacto and neolacto series. The protein-protein interaction network and module analysis identified 11 hub genes in the key modules. The CIBERSORTx algorithm revealed statistically significant differences in CD8+ T cells ( $P=0.013$ ), T follicular helper cells ( $P=0.002$ ), resting mast cells ( $P=0.004$ ), and neutrophils ( $P=0.002$ ) between patients with SA and mild-moderate asthma patients. Pearson’s correlation analysis identified 11 genes that were significantly associated with a variety of immune cells. We further predicted the utility of some potential drugs and validated our results in external datasets. Conclusion. Our results may help provide a better understanding of the relationship between the airway epithelial transcriptome and clinical data of SA. And this study will help to guide the development of SA-targeted molecular therapy.

Natural therapeutics and nutraceuticals for lung diseases: Traditional significance, phytochemistry, and pharmacology

BACKGROUND

Lung diseases including chronic obstructive pulmonary disease (COPD), infections like influenza, acute respiratory distress syndrome (ARDS), asthma and pneumonia lung cancer (LC) are common causes of sickness and death worldwide due to their remoteness, cold and harsh climatic conditions, and inaccessible health care facilities.

PURPOSE

Many drugs have already been proposed for the treatment of lung diseases. Few of them are in clinical trials and have the potential to cure infectious diseases. Plant extracts or herbal products have been extensively used as Traditional Chinese Medicine (TCM) and Indian Ayurveda. Moreover, it has been involved in the inhibition of certain genes/protiens effects to promote regulation of signaling pathways. Natural remedies have been scientifically proven with remarkable bioactivities and are considered a cheap and safe source for lung disease.

METHODS

This comprehensive review highlighted the literature about traditional plants and their metabolites with their applications for the treatment of lung diseases through experimental models in humans. Natural drugs information and mode of mechanism have been studied through the literature retrieved by Google Scholar, ScienceDirect, SciFinder, Scopus and Medline PubMed resources against lung diseases.

RESULTS

In vitro, in vivo and computational studies have been explained for natural metabolites derived from plants (like flavonoids, alkaloids, and terpenoids) against different types of lung diseases. Probiotics have also been biologically active therapeutics against cancer, anti-inflammation, antiplatelet, antiviral, and antioxidants associated with lung diseases.

CONCLUSION

The results of the mentioned natural metabolites repurposed for different lung diseases especially for SARS-CoV-2 should be evaluated more by advance computational applications, experimental models in the biological system, also need to be validated by clinical trials so that we may be able to retrieve potential drugs for most challenging lung diseases especially SARS-CoV-2.

Safety and Efficacy of Medicinal Plants Used to Manufacture Herbal Products with Regulatory Approval in Uganda: A Cross-Sectional Study

Introduction

The Uganda National Drug Authority requires phytochemical screening, freedom from microbial contamination, and evidence of safety and efficacy of the constituent plants to register herbal products. Since Uganda has no pharmacopeia, safety, efficacy, and plant processing information are not readily available. We documented the plant materials used to manufacture products in Uganda and established evidence of their safety and efficacy and availability of monographs.

Methods

The NDA register of herbal products was reviewed, and a product list was extracted. The herbal products were purchased from local pharmacies, and their labels were studied to identify plant ingredients and drug use. Literature was reviewed to document evidence of the safety and efficacy of the plant materials concerning manufacturer's claims. Also, the WHO and available African Pharmacopeia were searched to establish the availability of the plant monographs.

Results

Of the 84 NDA-registered local products, only 18 were obtained from the market; 82% were indicated for respiratory tract disorders. Thirty-three plant materials were listed with Eucalyptus globulus Labill, being the commonest. Several in vitro and in vivo studies demonstrate efficacy, thus supporting the use of the selected plant species for empirical treatment as stated on the product label. While most plants were safe, some species such as Albizia coriaria Oliv. had dose-dependent toxicities that cannot be predicted in combinations. The WHO, African Pharmacopoeia, and West African Herbal Pharmacopoeia had only 16 plant monographs of the 33 plants of interest. Nevertheless, Aloe vera (L.) Burm.f., Azadirachta indica A.Juss., Zingiber officinale Roscoe, and Allium sativum L. monographs were published by all three pharmacopoeias.

Conclusions

Preclinical evidence of safety and efficacy exists in the literature for most of the plants used to manufacture registered herbal products in Uganda. More specific bioassays and clinical trials are required for the products to provide conclusive evidence of safety and toxicity. Monographs are urgently needed for the Ugandan plants.

Immunomodulatory properties of triterpenes

The immune system is one of the main defence mechanisms of the human body. Inadequacy of this system or immunodeficiency results in increased risk of infections and tumours, whereas over-activation of the immune system causes allergic or autoimmune disorders. A well-balanced immune system is important for protection and for alleviation of these diseases. There is a growing interest to maintain a well-balanced immune system, especially after the Covid-19 pandemic. Many biological extracts, as well as natural products, have become popular due to their wide array of immunomodulatory effects and influence on the immune system. Triterpenes, one of the secondary metabolite groups of medicinal plants, exhibit immunomodulatory properties by various mechanisms. Different triterpenes, including components of commonly consumed plants, can promote some protection and alleviation of disease symptoms linked with immune responses and thus enhance overall well-being. This review aims to highlight the efficacy of triterpenes in light of the available literature evidence regarding the immunomodulatory properties of triterpenes. We have reviewed widely investigated immunomodulatory triterpenes; oleanolic acid, glycyrrhizin, glycyrrhetinic acid, pristimerin, ursolic acid, boswellic acid, celastrol, lupeol, betulin, betulinic acid, ganoderic acid, cucumarioside, and astragalosides which have important immunoregulatory properties. In spite of many preclinical and clinical trials were conducted on triterpenes related to their immunoregulatory actions, current studies have several limitations. Therefore, especially more clinical studies with optimal design is essential.

Lupeol reduces M1 macrophage polarization to attenuate immunologic dissonance and fatty acid deposition in rats with diet-induced metabolic syndrome

Background

This study aimed to investigate whether lupeol could inhibit the inflammatory mediators associated with the regulation of macrophage phenotypes and functions in rats with diet-induced metabolic syndrome (MS).

Methods

Forty specific-pathogen-free Sprague Dawley rats were fed a high-fat diet (HFD) for 10 weeks to establish an MS model. Lupeol was prepared and administered to the rats intraperitoneally at 20, 50, or 100 mg/kg (the lupeol 20 mg/kg, lupeol 50 mg/kg, and lupeol 100 mg/kg groups respectively). After 28 days of continuous intraperitoneal administration, rats were anesthesia and euthanasia. The obesity index, blood glucose and lipid metabolism indexes of rats in each group were measured. The levels of insulin and inflammatory factors in each group were detected by enzyme-linked immunosorbent assay (ELISA) kits. The pathological changes of liver tissue in rats were observed by hematoxylin and eosin (HE) and oil red O staining. The polarization levels of M1 and M2 macrophages in peripheral blood mononuclear cells (PBMCs) were analyzed by flow cytometry. The transcription levels of M1 and M2 macrophages markers were detected by qRT-PCR. The expressions of inducible nitric oxide synthase (iNOS) and arginase-1 (Arg-1) proteins in heart tissues of rats in each group were analyzed by Western blotting.

Results

Lupeol significantly recovered fasting blood glucose and serum insulin levels, and reduced the production of proinflammatory cytokines, including interleukin (IL)-6, tumor necrosis factor alpha (TNF-α), and monocyte chemoattractant protein-1 (MCP-1), in the liver. It also elevated the expression of anti-inflammatory cytokines, including IL-4 and IL-10, in the MS model. Further, after treatment with lupeol, the levels of total cholesterol, triacylglycerol and low-density lipoprotein (LDL) were decreased, and high-density lipoprotein (HDL) were increased. Importantly, in the MS model group, lupeol remarkably inhibited M1 macrophages polarization (F4/80⁺iNOS⁺) while elevating M2 macrophages polarization (F4/80⁺CD206⁺) remarkably. At the same time, the levels of M1 markers, including inducible nitric oxide synthase, IL-1β, IL-6, and TNF-α, were markedly inhibited, while those of M2 markers, such as arginase-1, IL-10, CD206, and TGF-β, were markedly elevated in the MS model rats.

Conclusions

Lupeol might promote M2 polarization of macrophages to relieve damage caused by MS.

Investigation of antinociceptive, antipyretic, antiasthmatic, and spasmolytic activities of Brazilian Cannabis sativa L. roots in rodents

ETHNOPHARMACOLOGICAL RELEVANCE

Many studies are performed with the aerial parts of Cannabis sativa L. (Cannabaceae). However, roots remain poorly studied, despite citations in the scientific literature. The C. sativa roots are indicated for the treatment of pain, inflammation, fever, among other health problems.

AIM OF THE STUDY

This study aimed to evaluate the antinociceptive, antipyretic, antiasthmatic, and spasmolytic activities of C. sativa roots in experimental models using mice and rats.

MATERIAL AND METHODS

The chemical composition of the aqueous extract of C. sativa roots (AECsR) was evaluated by LC-MS. The antinociceptive activity was assessed in mice by the induction of writhing with acetic acid, paw licking with formalin, and reactivity in the hot plate test. Fever was induced by the administration of a suspension of Saccharomyces cerevisiae in young rats. The asthmatic activity was performed with ovalbumin (OVA)-immunized mice with cellular and histological analysis. Finally, the spasmolytic activity was performed using mice isolated trachea. For in vivo studies, the doses were 12.5, 25, or 50 mg/kg whereas for in vitro, the concentration of AECsR was 729 μg/mL.

RESULTS

From the LC-MS data, we identified p-coumaroyltyramine, feruloyltyramine canabissativine in AECsR. The extract promoted a reduction of writhing in all tested doses (12.5, 25, or 50 mg/kg). Similarly, it reduced the pain in the formalin test at doses of 12.5 and 50 mg/kg (first phase) and 12.5 and 25 mg/kg (second phase). In the hot plate test, the doses of 12.5, 25, and 50 mg/kg promoted antinociceptive effect at different times, and the lowest dose maintained its action in the analyzes performed at 60, 90, and 120 min after administration. The anti-inflammatory activity of AECsR was observed in the mouse model of asthma, reducing the total leukocyte count in the bronchoalveolar fluid (BALF) at a dose of 25 mg/kg, as well as reducing eosinophilia in all tested doses (12.5, 25, and 50 mg/kg). Histological analysis of lungs stained with H&E and PAS showed a reduction in the number of inflammatory cells in the perivascular and peribronchial region, as well as reduced mucus production.

CONCLUSION

The results suggest that AECsR promotes pain control, either by a central or inflammatory mechanism, and has antiasthmatic activity. However, there was no antipyretic or spasmolytic effect.

Efficient In Vitro and In Vivo Anti-Inflammatory Activity of a Diamine-PEGylated Oleanolic Acid Derivative

Recent evidence has shown that inflammation can contribute to all tumorigenic states. We have investigated the anti-inflammatory effects of a diamine-PEGylated derivative of oleanolic acid (OADP), in vitro and in vivo with inflammation models. In addition, we have determined the sub-cytotoxic concentrations for anti-inflammatory assays of OADP in RAW 264.7 cells. The inflammatory process began with incubation with lipopolysaccharide (LPS). Nitric oxide production levels were also determined, exceeding 75% inhibition of NO for a concentration of 1 µg/mL of OADP. Cell-cycle analysis showed a reversal of the arrest in the G0/G1 phase in LPS-stimulated RAW 264.7 cells. Furthermore, through Western blot analysis, we have determined the probable molecular mechanism activated by OADP; the inhibition of the expression of cytokines such as TNF-α, IL-1β, iNOS, and COX-2; and the blocking of p-IκBα production in LPS-stimulated RAW 264.7 cells. Finally, we have analyzed the anti-inflammatory action of OADP in a mouse acute ear edema, in male BL/6J mice treated with OADP and tetradecanoyl phorbol acetate (TPA). Treatment with OADP induced greater suppression of edema and decreased the ear thickness 14% more than diclofenac. The development of new derivatives such as OADP with powerful anti-inflammatory effects could represent an effective therapeutic strategy against inflammation and tumorigenic processes.

Curcumol Ameliorates Lung Inflammation and Airway Remodeling via Inhibiting the Abnormal Activation of the Wnt/β-Catenin Pathway in Chronic Asthmatic Mice

Background

Curcumol exhibits anti-inflammatory effect, but its effect on chronic asthma lacked research. Therefore, this study explored the role of curcumol in asthma.

Methods

A chronic asthmatic mice model was established by ovalbumin induction. After treatment with curcumol, airway resistance in mice was detected by forced oscillation technique. The histopathological features of airway tissues, pulmonary inflammation, and inflammation cell recruitment in the bronchoalveolar lavage fluid (BALF) of mice were detected by hematoxylin-eosin staining. Collagen deposition in the airways of mice was examined by Masson staining. The secretion of ovalbumin-IgE, IL-4, IL-5, IL-13 in mouse serum and VEGFA secretion in BALF were analyzed by ELISA. Finally, the expressions of β-catenin, Wnt5a, VEGFA, TGF-β1, Fibronectin, and MMP-9 in mice lung tissues were determined by Western blot or immunohistochemical.

Results

Curcumol attenuated airway hyperresponsiveness, airway remodeling, and pulmonary inflammation in chronic asthmatic mice. Curcumol relieved collagen deposition in airway tissues, inflammation cell recruitment in BALF, and reduced the up-regulation of serum ovalbumin-IgE, IL-4, IL-5, and IL-13 and BALF VEGFA in chronic asthmatic mice. In addition, curcumol attenuated the up-regulated expressions of β-catenin, Wnt5a, VEGFA, TGF-β1, Fibronectin, and MMP-9 in the lung tissues of chronic asthmatic mice, but curcumol treatment did not show such effects on healthy mice.

Conclusion

Our findings revealed that curcumol could ameliorate lung inflammation and airway remodeling by inhibiting the abnormal activation of the Wnt/β-catenin pathway in chronic asthmatic mice, indicating that curcumol could be used as a novel anti-asthma drug for basic and clinical research.

Targeting the crosstalk between canonical Wnt/β-catenin and inflammatory signaling cascades: A novel strategy for cancer prevention and therapy

Emerging scientific evidence indicates that inflammation is a critical component of tumor promotion and progression. Most cancers originate from sites of chronic irritation, infections and inflammation, underscoring that the tumor microenvironment is largely orchestrated by inflammatory cells and pro-inflammatory molecules. These inflammatory components are intimately involved in neoplastic processes which foster proliferation, survival, invasion, and migration, making inflammation the primary target for cancer prevention and treatment. The influence of inflammation and the immune system on the progression and development of cancer has recently gained immense interest. The Wnt/β-catenin signaling pathway, an evolutionarily conserved signaling strategy, has a critical role in regulating tissue development. It has been implicated as a major player in cancer development and progression with its regulatory role on inflammatory cascades. Many naturally-occurring and small synthetic molecules endowed with inherent anti-inflammatory properties inhibit this aberrant signaling pathway, making them a promising class of compounds in the fight against inflammatory cancers. This article analyzes available scientific evidence and suggests a crosslink between Wnt/β-catenin signaling and inflammatory pathways in inflammatory cancers, especially breast, gastrointestinal, endometrial, and ovarian cancer. We also highlight emerging experimental findings that numerous anti-inflammatory synthetic and natural compounds target the crosslink between Wnt/β-catenin pathway and inflammatory cascades to achieve cancer prevention and intervention. Current challenges, limitations, and future directions of research are also discussed.

The treatment of asthma using the Chinese Materia Medica

ETHNOPHARMACOLOGICAL RELEVANCE

Asthma is a costly global health problem that negatively influences the quality of life of patients. The Chinese Materia Medica (CMM) contains remedies that have been used for the treatment of asthma for millennia. This article strives to systematically summarize the current research progress so that more comprehensive examinations of various databases related to CMM anti-asthma drugs, can be performed, so as to sequentially provide effective basic data for development and application of anti-asthma drugs based on the CMM.

MATERIALS AND METHODS

The research data published over the past 20 years for asthma treatment based on traditional CMM remedies were retrieved and collected from libraries and online databases (PubMed, ScienceDirect, Elsevier, Spring Link, Web of Science, PubChem Compound, Wan Fang, CNKI, Baidu, and Google Scholar). Information was also added from classic CMM, literature, conference papers on classic herbal formulae, and dissertations (PhD or Masters) based on traditional Chinese medicine.

RESULTS

This review systematically summarizes the experimental studies on the treatment of asthma with CMM, covering the effective chemical components, typical asthma models, important mechanisms and traditional anti-asthma CMM formulae. The therapy value of the CMM for anti-asthma is clarified, and the original data and theoretical research foundation are provided for the development of new anti-asthmatic data and research for the CMM.

CONCLUSIONS

Substantial progress against asthma has been made through relevant experimental research based on the CMM. These advances improved the theoretical basis of anti-asthma drugs for CMM and provided a theoretical basis for the application of a asthma treatment that is unique. By compiling these data, it is expected that the CMM will now contain a clearer mechanism of action and a greater amount of practical data that can be used for future anti-asthma drug research.

Phytochemical Constituents of Citrus hystrix DC. Leaves Attenuate Inflammation via NF-κB Signaling and NLRP3 Inflammasome Activity in Macrophages

Citrus hystrix DC. (CH) is found in many countries in Southeast Asia. This plant has been reported for anti-microbial, anti-cancer and anti-inflammatory bioactivities. However, the anti-inflammatory and anti-inflammasome properties of the leaves remain poorly understood. This study aimed to investigate the effect of CH leaves on NLRP3 and NF-κB signaling pathways. CH leaves were sequentially extracted using hexane, ethyl acetate and 95% ethanol to give three crude extracts. An active compound, lupeol was fractionated from the ethanolic extract using chromatographic techniques, and its structure was identified and confirmed by spectroscopic methods. Anti-inflammatory activities were observed on both lipopolysaccharide-stimulated and NLRP3 adenosine triphosphate-induced macrophages. The release of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) was analyzed by Enzyme-Linked Immunosorbent Assay (ELISA). Real-time qRT-polymerase chain reaction (PCR) was used to measure inflammatory-associated gene expression. NF-κB protein expressions were investigated using the immunoblotting technique. The active fraction of ethanolic CH leaves and lupeol significantly reduced the release of pro-inflammatory cytokines and suppressed the expression of both inflammasome genes and NF-κB proteins. The ethanolic extract of CH leaves and lupeol showed potent anti-inflammatory activities by targeting NF-κB and NLRP3 signaling pathways.

Health benefits of 4,4-dimethyl phytosterols: an exploration beyond 4-desmethyl phytosterols

4,4-Dimethyl phytosterols possess two methyl groups at the carbon-4 atom of the aliphatic A-ring. The methyl groups are crucial for the molecular recognition of endogenous and exogenous bioactive compounds. Phytosterols have received worldwide attention owing to their recognized health benefits. However, 4,4-dimethyl phytosterols are less appreciated. Recent research studies revealed that 4,4-dimethyl phytosterols exert numerous beneficial effects on disease prevention, and are particularly involved in the endogenous cannabinoid system (ECS). The purpose of this review is to summarize and highlight the currently available information regarding the structures and sources of 4,4-dimethyl phytosterols, and to provide detailed preclinical studies performed to evaluate their potential for treating various diseases. Future research on 4,4-dimethyl phytosterols is warranted to confirm their relationship with the ECS, and to elucidate the mechanism directly toward clinical trials.

Lupeol Counteracts the Proinflammatory Signalling Triggered in Macrophages by 7-Keto-Cholesterol: New Perspectives in the Therapy of Atherosclerosis

Macrophage activation and polarization play a central role in atherosclerotic plaque fate. The M1/M2 activation phenotypes represent two profiles of the macrophage polarization state. During atherosclerosis regression or stabilization, macrophages switch from M1 proinflammatory phenotype to M2 anti-inflammatory reparative one. Here, we investigated whether the natural compound lupeol, a pentacyclic triterpene, induces phenotypical and functional changes in human M1 macrophages and counteracts the proinflammatory signalling triggered by 7-keto-cholesterol (7KC), a major product of oxidative stress-mediated cholesterol oxidation. Flow cytometric and immunochemical analysis showed that the treatment with lupeol of M1 monocyte-derived macrophages M_(IFN-γ/LPS) specifically stimulated these cells to upregulate the expression of the anti-inflammatory cytokines interleukin- (IL-)10 and TGF-β, and of the scavenger receptor CD36, whereas downregulated the proinflammatory cytokine IL-12 and the M1 activation marker HLA-DR. Pretreatment of macrophages with lupeol prevented the release of IL-12, IL-1β, and the upregulation of HLA-DR expression triggered by 7KC and increased the IL-10 production and CD36 expression. This treatment also prevented the impairment of endocytosis triggered by 7KC and prevented 7KC-induced foam cell formation by reducing the lipid droplet accumulation in M1-polarized THP-1 macrophages, whereas showed an additive effect in reactive oxygen species (ROS) production. Western blotting analysis of autophagy markers LC3-I/II and p62-SQSTM1 in M1-polarized THP-1 macrophages demonstrated that lupeol activated autophagy as indicated by increased LC3-II levels, and by marked inhibition of p62. These findings indicate that lupeol has a cytoprotective effect on 7KC-proinflammatory signalling by efficiently switching the macrophage polarization toward an anti-inflammatory phenotype, probably through the activation of the autophagy pathway by increasing ROS production, the reduction of cellular lipid accumulation, and an overall reduction of proinflammatory phenotype. Thus, our data demonstrating an anti-inflammatory and immunomodulatory activity of lupeol in human M1 macrophages suggest its usefulness as an adjunctive drug in the therapy of atherosclerosis.

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.

Modulation of cell signaling pathways by Phyllanthus amarus and its major constituents: potential role in the prevention and treatment of inflammation and cancer

The causal and functional connection between inflammation and cancer has become a subject of much research interest. Modulation of cell signaling pathways, such as those involving mitogen activated protein kinases (MAPKs), nuclear factor kappa β (NF-κB), phosphatidylinositol 3-kinase and protein kinase B (PI3K/Akt), and Wnt, and their outcomes play a fundamental role in inflammation and cancer. Activation of these cell signaling pathways can lead to various aspects of cancer-related inflammation. Hence, compounds able to modulate inflammation-related molecular targets are sought after in anticancer drug development programs. In recent years, plant extracts and their metabolites have been documented with potential in the prevention and treatment of cancer and inflammatory ailments. Plants possessing anticancer and anti-inflammatory properties due to their bioactive constituents have been reported to modulate the molecular and cellular pathways which are related to inflammation and cancer. In this review we focus on the flavonoids (astragalin, kaempferol, quercetin, rutin), lignans (phyllanthin, hypophyllanthin, and niranthin), tannins (corilagin, geraniin, ellagic acid, gallic acid), and triterpenes (lupeol, oleanolic acid, ursolic acid) of Phyllanthus amarus, which exert various anticancer and anti-inflammatory activities via perturbation of the NF-κB, MAPKs, PI3K/Akt, and Wnt signaling networks. Understanding the underlying mechanisms involved may help future research to develop drug candidates for prevention and new treatment for cancer and inflammatory diseases.

Anti-inflammatory activity of SintMed65, an N-acylhydrazone derivative, in a mouse model of allergic airway inflammation

Asthma is a chronic, complex and heterogeneous inflammatory illness, characterized by obstruction of the lower airways. About 334 million people worldwide suffer from asthma, and these estimates, as well as the severity of the disease, have increased in the last decades. Glucocorticoids are currently the most widely used drugs in the treatment and control of asthma symptoms, but their prolonged use can cause serious adverse effects. N-acylhydrazone derivatives have been tested in pre-clinical studies in models of inflammatory diseases. Here we tested SintMed65 (N'-[(1E)-3-(4-nitrophenylhydrazono)]-(2E)-propan-2-ylidene-3,5-dinitrobenzohydrazide), a compound belonging to a novel class of immunosuppressive drugs, in a mouse model of allergic airway inflammation. BALB/c mice were sensitized previously and challenged with ovalbumin for five consecutive days and SintMed65 treatment was performed orally 1 h prior to challenge with ovalbumin. Administration of SintMed65, as well as the reference drug dexamethasone, reduced cellularity and the number of eosinophils in the bronchoalveolar fluid (BALF). SintMed65 also reduced the production of Th2 cytokines IL-4, IL-5 and IL-13 in the BALF, and IL-4, IL-10 and CCL8 gene expression in lung, compared to vehicle-treated mice. Importantly, a reduction in the number of leukocytes and in the mucus production in lungs of SintMed65-treated mice was found, compared to the vehicle-treated group. In contrast, IgE production was not significantly altered after treatment with SintMed65. Our results demonstrate that compound SintMed65 possesses anti-inflammatory characteristics, suggesting its therapeutic potential for the treatment of allergic diseases.

Evaluation of Anti-HIV-1 Integrase and Anti-Inflammatory Activities of Compounds from Betula alnoides Buch-Ham

Betula alnoides is a medicinal plant in Thai traditional longevity preparations. The crude extracts of this plant possess various biological activities. However, the isolated compounds from this plant have no reports of anti-HIV-1 integrase (IN) activity. Therefore, the present study aims to investigate the anti-HIV-1 integrase and anti-inflammatory effects of isolated compounds from this plant and predict the interaction of compounds with integrase active sites. From the bioassay-guided fractionation of the ethanol extract of B. alnoides stems using chromatographic techniques, five pentacyclic triterpenoid compounds were obtained. They are betulinic acid (1), betulin (2), lupeol (3), oleanolic acid (4), and ursolic acid (5). Compound 2 exhibited the most potent inhibitory activity against HIV-1 IN, with an IC₅₀ value of 17.7 μM. Potential interactions of compounds with IN active sites were investigated using computational docking. The results indicated that active compounds interacted with Asp64, a residue participating in 3′-processing, and Thr66, His67, and Lys159, residues participating in strand-transfer reactions of the integration process. Regarding anti-inflammatory activity, all compounds exerted significant inhibitory effects on LPS-induced nitric oxide production (IC₅₀ < 68.7 μM). Thus, this research provides additional scientific support for the use of B. alnoides in traditional medicine for the treatment of HIV patients.

Advanced Molecular Knowledge of Therapeutic Drugs and Natural Products Focusing on Inflammatory Cytokines in Asthma

Asthma is a common respiratory disease worldwide. Cytokines play a crucial role in the immune system and the inflammatory response to asthma. Abnormal cytokine expression may lead to the development of asthma, which may contribute to pathologies of this disease. As cytokines exhibit pleiotropy and redundancy characteristics, we summarized them according to their biologic activity in asthma development. We classified cytokines in three stages as follows: Group 1 cytokines for the epithelial environment stage, Group 2 cytokines for the Th2 polarization stage, and Group 3 cytokines for the tissue damage stage. The recent cytokine-targeting therapy for clinical use (anti-cytokine antibody/anti-cytokine receptor antibody) and traditional medicinal herbs (pure compounds, single herb, or natural formula) have been discussed in this review. Studies of the Group 2 anti-cytokine/anti-cytokine receptor therapies are more prominent than the studies of the other two groups. Anti-cytokine antibodies/anti-cytokine receptor antibodies for clinical use can be applied for patients who did not respond to standard treatments. For traditional medicinal herbs, anti-asthmatic bioactive compounds derived from medicinal herbs can be divided into five classes: alkaloids, flavonoids, glycosides, polyphenols, and terpenoids. However, the exact pathways targeted by these natural compounds need to be clarified. Using relevant knowledge to develop more comprehensive strategies may provide appropriate treatment for patients with asthma in the future.

Regulation of the levels of health promoting compounds: lupeol, mangiferin and phenolic acids in the pulp and peel of mango fruit: a review

There is a demand for feasible methodologies that can increase/maintain the levels of health-promoting phytochemicals in horticultural produce, due to strong evidence that these compounds can reduce risk of chronic diseases. Mango (Mangifera indica L.), ranks fifth among the most cultivated fruit crops in the world, is naturally rich in phytochemicals such as lupeol, mangiferin and phenolic acids (e.g. gallic acid, chlorogenic acid and vanillic acid). Yet, there is still much scope for up-regulating the levels of these compounds in mango fruit through manipulation of different preharvest and postharvest practices that affect their biosynthesis and degradation. The process of ripening, harvest maturity, physical and chemical elicitor treatments such as low temperature stress, methyl jasmonate (MeJA), salicylic acid (SA) and nitric oxide (NO) and the availability of enzyme cofactors (Mg²⁺ , Mn²⁺ and Fe²⁺ ) required in terpenoid biosynthesis were identified as potential determinants of the concentration of health-promoting compounds in mango fruit. The effectiveness of these preharvest and postharvest approaches in regulating the levels of lupeol, mangiferin and phenolic acids in the pulp and peel of mango fruit will be discussed. In general spray application of 0.2% iron(II) sulphate (FeSO₄ ) 30 days before harvest, harvest at sprung stage, storage of mature green fruit at 5 °C for 12 days prior to ripening, fumigation of mature green fruit with 10^-5  mol L^-1 and/or 10^-4  mol L^-1 MeJA for 24 h or 20 and/or 40 µL L^-1 NO for 2 h upregulate the levels of lupeol, mangiferin and phenolic acids in pulp and peel of ripe mango fruit. © 2019 Society of Chemical Industry.

Anti-inflammatory potential of hecogenin on atopic dermatitis and airway hyper-responsiveness by regulation of pro-inflammatory cytokines

Objective: Hecogenin is a sapogenin found in Agave sisalana species that is used extensively for the treatment of anti-inflammatory, antifungal, hypotensive, anti-nociceptive activity and cancer. We have studied the anti-inflammatory effect of Hecogenin and its combination with Fluticasone on atopic dermatitis and airway hyper-responsiveness in Balb/c mice. Material and methods: Dermatitis was induced by repeated application of 2, 4-dinitrofluorobenzene in Balb/c mice. After a topical application of Hecogenin, Fluticasone and their combination on the skin lesions, the ear thickness, ear weight and erythema score were evaluated. Asthma was induced by sensitization and challenge of ovalbumin in Balb/c mice. Results: The topical application of Hecogenin and its combination with Fluticasone in mice effectively suppressed the ear swelling and weight. As well as the levels of pro-inflammatory cytokines were decreased by Hecogenin and its combination in-vivo. Whereas, intra-nasal administration of Hecogenin and its combination in ovalbumin induced airway hyper-responsiveness reveals a significant decrement in total cell count, differential cell count and cytokines levels. Similar observations were obtained for myeloperoxidase level in ear and lung tissue. The results were supported by histological studies of ear and lung tissue. Conclusion: These data indicate that Hecogenin has been proved as a potential therapy for allergic skin diseases and bronchial asthma treatments in combination with Fluticasone by reducing its dose from 50 to 25 μg/mice in combination to circumvent the long term side effects of Fluticasone. The beneficial effect of Hecogenin may be related to the diminution of TNF-α and IL-12 cytokines production in Balb/c mice.

Ethnomedicinal, phytochemical and pharmacological profile of a mangrove plant Ceriops Decandra GriffDin Hou

Ceriops decandra is a mangrove tree species, reputed for its folkloric uses in the treatment of gastrointestinal disorders, infection, snakebites, inflammation, and cancer. Different parts of the plant are rich with various phytoconstituents which include diterpenoids (ceriopsin A-G), triterpenoids (lupeol, α-amyrin, oleanolic acid, ursolic acid), and phenolics (catechin, procyanidins).These phytoconstituents and their derivatives could form a new basis for developing new drugs against various diseases. The objective of the present study is to compile the phytochemical, ethnobotanical, biological, and pharmacological significance of the plant to provide directions for future research to find out therapeutically active lead compounds for developing new drugs against diseases of current interest including diabetes, inflammation, and cancer.

Phytochemicals as modulators of M1-M2 macrophages in inflammation

Macrophages are critical mediators of the innate immune response against foreign pathogens, including bacteria, physical stress, and injury. Therefore, these cells play a key role in the "inflammatory pathway" which in turn can lead to an array of diseases and disorders such as autoimmune neuropathies and myocarditis, inflammatory bowel disease, atherosclerosis, sepsis, arthritis, diabetes, and angiogenesis. Recently, more studies have focused on the macrophages inflammatory diseases since the discovery of the two subtypes of macrophages, which are differentiated on the basis of their phenotype and distinct gene expression pattern. Of these, M1 macrophages are pro-inflammatory and responsible for inflammatory signaling, while M2 are anti-inflammatory macrophages that participate in the resolution of the inflammatory process, M2 macrophages produce anti-inflammatory cytokines, thereby contributing to tissue healing. Many studies have shown the role of these two subtypes in the inflammatory pathway, and their emergence appears to decide the fate of inflammatory signaling and disease progression. As a next step in directing the pro-inflammatory response toward the anti-inflammatory type after an insult by a foreign pathogen (e. g., bacterial lipopolysaccharide), investigators have identified many natural compounds that have the potential to modulate M1 to M2 macrophages. In this review, we provide a focused discussion of advances in the identification of natural therapeutic molecules with anti-inflammatory properties that modulate the phenotype of macrophages from M1 to M2.

Tolerogenic Dendritic Cells Reduce Airway Inflammation in a Model of Dust Mite Triggered Allergic Inflammation

PURPOSE

The use of tolerogenic dendritic cells (TolDCs) to control exacerbated immune responses may be a prophylactic and therapeutic option for application in autoimmune and allergic conditions. The objective of this work was to evaluate the effects of TolDC administration in a mouse model of allergic airway inflammation caused by mite extract.

METHODS

Mouse bone marrow-derived TolDCs were induced by incubation with granulocyte-macrophage colony-stimulating factor (GM-CSF) and dexamethasone, and then characterized by flow cytometry and cytokine production by enzyme-linked immunosorbent assay (ELISA). For the in vivo model of Blomia tropicalis-induced allergy, mice transplanted with antigen-pulsed TolDCs were sensitized intraperitoneally with B. tropicalis mite extract (BtE) adsorbed to aluminium hydroxide. After challenge by nasal administration of BtE, bronchoalveolar lavage fluid (BALF), lungs, spleen and serum were collected for analysis.

RESULTS

Induction of TolDCs was efficiently achieved as shown by low expression of major histocompatibility complex (MHC) II, programmed death-ligand (PD-L) 2 and pro-inflammatory cytokine production, and up-regulation of interleukin (IL)-10, upon LPS stimulation in vitro. Transplantation of 1 or 2 doses of BtE-pulsed TolDCs reduced the number of inflammatory cells in BALF and lungs as well as mucus deposition. Moreover, compared to saline-injected controls, TolDC-treated mice showed lower serum levels of anti-BtE immunoglobulin E (IgE) antibodies as well as reduced Gata3 and IL-4 gene expression in the lungs and decreased IFN-γ levels in the supernatant of splenocyte cultures Transplantation of TolDCs increased the percentage of the regulatory T cells in the spleen and the lungs.

CONCLUSIONS

Preventive treatment with TolDCs protects against dust mite-induced allergy in a mouse model, reinforcing the use of tolerogenic dendritic cells for the management of allergic conditions.

Lupeol and Its Role in Chronic Diseases

Lupeol belongs to pentacyclic lupane-type triterpenes and exhibits in edible vegetables, fruits and many plants. Many researches indicated that lupeol possesses many beneficial pharmacological activities including antioxidant, anti-inflammatory, anti-hyperglycemic, anti-dyslipidemic and anti-mutagenic effects. From various disease-targeted animal models, these reports indicated that lupeol has anti-diabetic, anti-asthma, anti-arthritic, cardioprotective, hepatoprotective, nephroprotective, neuroprotective and anticancer efficiency under various routes of administration such as topical, oral, subcutaneous, intraperitoneal and intravenous. It is worth mentioning that clinical trials of lupeol were performed to treat canine oral malignant melanoma and human moderate skin acne in Japan and Korea. The detailed mechanism of anti-inflammatory, anti-diabetic, hepatoprotective and anticancer activities was further reviewed from published papers. These evidence indicate that lupeol is a multi-target agent to exert diverse pharmacological potency with many potential targeting proteins such as α-glucosidase, α-amylase, protein tyrosine phosphatase 1B (PTP 1B) and TCA cycle enzymes and targeting pathway such as IL-1 receptor-associated kinase-mediated toll-like receptor 4 (IRAK-TLR4), Bcl-2 family, nuclear factor kappa B (NF-kB), phosphatidylinositol-3-kinase (PI3-K)/Akt and Wnt/β-catenin signaling pathways. This review also provides suggestion that lupeol might be a valuable and potential lead compound to develop as anti-inflammatory, anti-diabetic, hepatoprotective and anticancer drugs.

Anti-neuroinflammatory Activity of Elephantopus scaber L. via Activation of Nrf2/HO-1 Signaling and Inhibition of p38 MAPK Pathway in LPS-Induced Microglia BV-2 Cells

Elephantopus scaber L. (family: Asteraceae) has been traditionally utilized as a folkloric medicine and scientifically shown to exhibit anti-inflammatory activities in various in vivo inflammatory models. Given the lack of study on the effect of E. scaber in neuroinflammation, this study aimed to investigate the anti-neuroinflammatory effect and the underlying mechanisms of ethyl acetate fraction from the leaves of E. scaber (ESEAF) on the release of pro-inflammatory mediators in lipopolysaccharide (LPS)-induced microglia cells (BV-2). Present findings showed that ESEAF markedly attenuated the translocation of NF-κB to nucleus concomitantly with the significant mitigation on the LPS-induced production of NO, iNOS, COX-2, PGE₂, IL-1β, and TNF-α. These inflammatory responses were reduced via the inhibition of p38. Besides, ESEAF was shown to possess antioxidant activities evident by the DPPH and SOD scavenging activities. The intracellular catalase enzyme activity was enhanced by ESEAF in the LPS-stimulated BV-2 cells. Furthermore, the formation of ROS induced by LPS in BV-2 cells was reduced upon the exposure to ESEAF. Intriguingly, the reduction of ROS was found in concerted with the activation of Nrf2 and HO-1. It is conceivable that the activation promotes the scavenging power of antioxidant enzymes as well as to ameliorate the inflammatory response in LPS-stimulated BV-2 cells. Finally, the safety profile analysis through oral administration of ESEAF at 2000 mg/kg did not result in any mortalities, adverse effects nor histopathologic abnormalities of organs in mice. Taken altogether, the cumulative findings suggested that ESEAF holds the potential to develop as nutraceutical for the intervention of neuroinflammatory disorders.

Uvaol attenuates pleuritis and eosinophilic inflammation in ovalbumin-induced allergy in mice

Uvaol, a triterpene present in olives and virgin olive oil, has been shown to possess anti-inflammatory properties and antioxidant effects. However, until now, no studies have demonstrated its potential effects on allergic inflammation. The aim of this study was to evaluate the anti-inflammatory effects of uvaol in a mouse model of allergy characterized by eosinophil-dominant inflammation in actively sensitized mice. The anti-inflammatory effect of uvaol was analyzed in two murine models of allergic inflammation (pleurisy and asthma). In these models, Swiss mice were sensitized and challenged with ovalbumin (OVA). In the pleurisy model, the pleural eosinophilic inflammation and IL-5 concentrations were examined 24h after the OVA challenge, while in the asthma model were examined the airway inflammation via bronchoalveolar lavage (BAL) fluid cytology and lung histopathology analyses. Our results showed that uvaol decreased the accumulation of eosinophils and the concentration of IL-5 in pleural effluent. Uvaol also demonstrated important anti-inflammatory activity by inhibiting production of IL-5 and influx of leukocytes, mainly of eosinophils, in BAL fluid, but without interfering with levels of reactive oxygen species in leukocytes. Moreover, the eosinophil infiltration, mucus production, number of alveoli that collapsed, and IL-5 levels in the lung were clearly decreased by uvaol treatment. These findings indicate that uvaol can be a good candidate for the treatment of allergic inflammation by inhibiting eosinophil influx and IL-5 production in ovalbumin-induced allergy.

The pentacyclic triterpene Lupeol switches M1 macrophages to M2 and ameliorates experimental inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, is a chronic inflammatory disease in the lower gastrointestinal tract. Mounting evidence suggests that the predominance of the classically activated (M1) macrophages versus the alternatively activated (M2) macrophages plays a role in the progression of IBD. Thus, agents able to shift pro-inflammatory M1 macrophages to anti-inflammatory M2 macrophages may be beneficial to IBD. The pentacyclic triterpene Lup-20(29)-en-3β-ol (Lupeol), a potent anti-inflammatory natural product, has been shown to inhibit pro-inflammatory cytokine production, suggesting it is potentially able to modulate macrophage polarization, thereby beneficial to IBD.

METHODS

CD4(+) monocytes were differentiated to M1 or M2 macrophages, which were cocultured with epithelial cell lines, T84 and Caco-2, in the absence or presence of Lupeol (10μM). Experimental colitis was induced with dextran sodium sulfate (DSS), with or without oral administration of Lupeol (50mg/kg, q.d.). Cytokines were measured with Luminex kits. M1/M2 genes were measured with real-time polymerase chain reaction. Macrophage phenotypes were defined by measuring M1 and M2 markers with confocal microscopy. Proteins were measured with Western blotting, while cell surface markers were measured with confocal microscopy or flow cytometry. Histology was evaluated with H&E staining.

RESULTS

Treatment of M1 macrophages with Lupeol resulted in a marked decrease in the production of pro-inflammatory cytokines, including IL-12, IL6, IL-1β and TNFα, and a marked increase in the production of IL-10, an anti-inflammatory cytokine. This was associated with a down-regulation of CD86, a typical marker of M1 macrophages, and an up-regulation of CD206, a typical M2 macrophage marker. IRF5, a transcription factor that is critically involved in M1 polarization, was down-regulated in M1 macrophages after being incubated with Lupeol, associated with a marked decrease in the phosphorylation of p38 mitogen activated protein kinase. Coculture of epithelial cells with M1 macrophages resulted in down-regulation of the tight junction protein ZO-1 and disruption of epithelial integrity, which were blocked by Lupeol treatment of the M1 macrophages. Moreover, oral administration of Lupeol to dextran sulfate sodium (DSS)-induced colitis mice resulted in mitigated intestinal inflammation and increased survival from lethal colitis, associated with decreased expression of M1-related genes and increased expression of M2-related genes.

CONCLUSION

Lupeol ameliorates experimental inflammatory bowel disease through, at least in part, inhibiting M1 and promoting M2 macrophages.

Morphological and release characterization of nanoparticles formulated with poly (dl-lactide-co-glycolide) (PLGA) and lupeol: In vitro permeability and modulator effect on NF-κB in Caco-2 cell system stimulated with TNF-α

Lupeol exhibits anti-inflammatory effects; unfortunately it shows low water solubility. An alternative to overcome this is the development of nanomaterials. Several methods for nanomaterial production are available. One of them is emulsification/solvent-evaporation. The objective of the present work was to evaluate physical properties, transport and in vitro modulator effects on NF-κB of poly (lactide-co-glycolide) (PLGA) nanoparticles loaded with lupeol. Nanonutraceuticals were prepared with 16% (w/v) of lupeol. Size distribution and morphology were measured by particle size analyzer and TEM. In vitro release of lupeol was studied by three different models: Higuchi, Siepmann & Peppas, and Power law. Transport of nanonutraceutical was studied in a Caco-2 cell model and by GC-MS. Modulator effect on NK-κB was studied by western blot analysis. Nanonutraceuticals were 10% larger than the nanoparticles without lupeol (372 vs 337 nm) and presented a broader size distribution (0.28 vs 0.22). TEM results displayed spherical structures with a broader size distribution. Entrapment efficiency of lupeol was 64.54% and it in vitro release data fitted well to the Power law and Higuchi equation (R > 0.84-0.84). Strong regulation of NF-κB of nanonutraceutical was observed. It was not observed any transport across the Caco-2 cell model at the different experimental conditions.

Farnesol, a sesquiterpene alcohol in herbal plants, exerts anti-inflammatory and antiallergic effects on ovalbumin-sensitized and -challenged asthmatic mice

To investigate the effect of farnesol on allergic asthma, three farnesol doses were extra-added into AIN-76 feed consumed by ovalbumin- (OVA-) sensitized and -challenged mice continuously for 5 weeks, at approximately 5, 25, and 100 mg farnesol/kg, BW/day. The results showed that there were no significant differences in body weight, feed intake, and visceral organ weights between the farnesol supplementation and dietary control groups. Farnesol supplementation decreased interleukin (IL)-6/IL-10 level ratios in bronchoalveolar lavage fluid (BALF). Farnesol supplementation significantly (P < 0.05) restored the cytokine secretion ability of peritoneal macrophages that was suppressed as a result of OVA sensitization and challenge and slightly decreased tumor necrosis factor (TNF-α)/IL-10 cytokine secretion ratios. Farnesol supplementation slightly (P > 0.05) decreased IL-4 but significantly (P < 0.05) increased IL-2 levels secreted by the splenocytes in the presence of OVA, implying that farnesol might have a systemic antiallergic effect on allergic asthmatic mice. Farnesol supplementation significantly (P < 0.05) increased IL-10 levels secreted by the splenocytes in the presence of OVA, suggesting that farnesol might have an anti-inflammatory potential to allergic asthmatic mice. Overall, our results suggest that farnesol supplementation may be beneficial to improve the Th2-skewed allergic asthmatic inflammation.

Comparative binding mechanism of lupeol compounds with plasma proteins and its pharmacological importance

Binding of lupeol compounds with plasma proteins.

Assessment of inhibitory potential of Pothos scandens L. on ovalbumin-induced airway hyperresponsiveness in balb/c mice

Pothos scandens L. was used in Indian traditional medicine as an antiasthmatic drug. The ethanolic and aqueous extracts were prepared with aerial parts of P. scandens (PSE & PSA). ESI MS/MS of PSE ethanolic extract was carried out for the determination of chemical constituents. CP1 is isolated from the PSE, structurally confirmed with NMR and LCMS/MS. PSE, PSA and CP1 are evaluated against ovalbumin (OVA) induced airway hyperresponsiveness (AHR) in balb/c mice. The test drugs are administered p.o. prior to challenge with aerosolized 2.5% w/v OVA. Total and differential leucocyte count, nitrite (NO2), nitrate (NO3), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-13 (IL-13) are estimated in bronchoalveolar lavage fluid (BALF). Similarly, myeloperoxidase (MPO), malonaldehyde (MDA) and total lung protein (TLP) are estimated in the lungs. The results reveal a significant increase in total and differential leucocyte count, NO2, NO3, TNF-α, IL-6, and IL-13 in OVA induced AHR. However, these parameters are significantly decreased in PSE and PSA tested doses (PSE 100 & 200mg/kg). While, treatment with CP1 is less effective at 5 & 10mg/kg doses. Similar observations obtain for MPO and MDA in lungs. However, the mean value indicated that the PSE at 200mg/kg showed a significant restoration in all the parameters. Pro-inflammatory mediators are known to be responsible for AHR. Histopathology revealed justifies the effectiveness. The present investigations suggest PSE are interesting molecules for further research for asthma, with an approach through pro-inflammatory inhibitory pathway. P. scandens is a potential herbal medicine for allergy induced asthma.

The dietary terpene lupeol targets colorectal cancer cells with constitutively active Wnt/β-catenin signaling

SCOPE

Aberrant activation of the Wingless-type mouse mammary tumor virus integration site family (Wnt)/β-catenin signaling pathway is the most common modification, and often considered, a hallmark of colorectal cancer (CRC). Typically in this pathway the β-catenin translocates from the cytoplasm to the nucleus, where it functions as a transcription regulator of several genes that support tumor formation and progression. Thus, any agent that could attenuate the translocation of β-catenin could be extremely valuable against CRC, especially the tumors that exhibit constitutively active Wnt/β-catenin signaling.

METHODS AND RESULTS

Using human CRC cells that exhibit differential expression of Wnt/β-catenin signaling, we demonstrate that treatment of CRC cells with dietary triterpene lupeol results in a dose-dependent (i) decrease in cell viability, (ii) induction of apoptosis, (iii) decrease in colonogenic potential, (iv) decrease in β-catenin transcriptional activity, and (v) decrease in the expression of Wnt target genes. Most importantly lupeol was observed to inhibit the translocation of β-catenin from the cytoplasm to the nucleus. Importantly, all these effects of lupeol were restricted to cells that harbor constitutively active Wnt/β-catenin signaling while negligible effects were observed in cells that lack constitutively active Wnt/β-catenin signaling. Further, we also demonstrate that inhibition of Wnt signaling in cells with constitutive active Wnt/β-catenin results in loss of lupeol efficacy while inducing Wnt signaling sensitizes the cells to inhibitory effects of lupeol.

CONCLUSION

In summary, our data strongly advocate the efficacy of lupeol against CRC cells that exhibit constitutively active Wnt/β-catenin signaling.

Antinociceptive effect of lupeol: evidence for a role of cytokines inhibition

The present study investigates the antinociceptive properties of lupeol in models of inflammatory and post-operative pain, as well as its mechanisms of action. The effects of lupeol were tested against acetic acid-induced writhing, formalin test, carrageenan-induced hyperalgesia, and post-operative pain model. Cytokine levels were determined by ELISA. Mice motor performance was evaluated in the rota rod and open-field tests. Pre-treatment of mice with lupeol (5-100 mg/kg IP) produced a dose-related inhibition of writhing in mice. The maximal antinociception produced by lupeol (60 mg/kg) was unaffected in mice pre-treated with yohimbine (α2 adrenoceptor antagonist; 2 mg/kg IP), L-arginine (substrate for nitric oxide synthase; 600 mg/kg IP), glibenclamide (the KATP-channel blocker; 2 mg/kg IP), and methysergide maleate (serotoninergic receptors antagonist; 5 mg/kg IP). Furthermore, lupeol (25-100 mg/kg) inhibited the late phase of formalin test. Pre-treatment with lupeol (50 and 100 mg/kg) inhibited the hyperalgesia and the local increase in tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels induced by carrageenan. In contrast, lupeol did not inhibit the post-operative pain. Lupeol-treated mice did not show any motor performance alterations or apparent systemic toxicity. Our results demonstrate that lupeol has consistent antinociceptive properties during inflammatory pain, but not post-operative pain, acting through the inhibition of IL-1β and TNF-α production.

Modulation of Wnt/β-catenin signaling pathway by bioactive food components

The Wnt/β-catenin signaling pathway, one of the most conserved intercellular signaling cascade, is a known regulator of cellular functions related to tumor initiation and progression, cell proliferation, differentiation, survival and adhesion. Because aberrant Wnt/β-catenin signaling has been observed in a variety of human cancers including a majority of colorectal cancers, about half of prostate cancers and a third of melanomas, inhibitors of its complex signaling pathways are being investigated for therapy as well as chemoprevention of these cancers. During the last decade, several naturally occurring dietary agents have been shown to target intermediates in the Wnt/β-catenin signaling pathway. In this review, we highlight the current understanding of the Wnt/β-catenin signaling pathway and present an analysis of the key findings from laboratory studies on the effects of a panel of dietary agents against a variety of cancers. Promise of these agents for treating and preventing human cancer is then discussed.

Effects of aqueous extract of Echinodorus grandiflorus on the immune response in ovalbumin-induced pulmonary allergy

BACKGROUND

Asthma is a disease characterized by intermittent obstruction of the airways and chronic inflammation that affects approximately 300 million people worldwide. The immune response in asthma is predominantly T(H)2, with high levels of total and allergen-specific IgE and bronchial eosinophilia. Asthma treatment is aimed at controlling the disease, and the drugs used currently have systemic adverse effects and generally are not effective in difficult-to-control cases.

OBJECTIVE

To investigate the effect of aqueous extract of Echinodorus grandiflorus, a plant used in folk medicine for its diuretic and anti-inflammatory properties, in a model of pulmonary allergy.

METHODS

BALB/c mice were intraperitoneally sensitized and nasally challenged with ovalbumin. Aqueous extract and dexamethasone treatments (0.1 mL/d per mouse) were initiated on day 32 and concluded on day 40. Eight hours after the last challenge evaluations, of serum, bronchoalveolar lavage, and lung tissue were performed.

RESULTS

Oral treatment with the extract markedly reduced the number of total cells and eosinophils in bronchoalveolar lavage. The eosinophil peroxidase activity in lung tissue, the levels of ovalbumin-specific IgE in serum, the levels of CCL11, and the gene expression of interleukin 4 and interleukin 13 in lung tissue were also lower after treatment.

CONCLUSIONS

These results suggest that the aqueous extract of E grandiflorus is able to modulate allergic pulmonary inflammation and may be useful as a potential therapeutic agent for asthma.

Anti-inflammatory effects and possible mechanism of action of lupeol acetate isolated from Himatanthus drasticus (Mart.) Plumel

BACKGROUND

The species Himatanthus drasticus is popularly known in Northeast Brazil as "janaguba" and belongs to the family Apocynaceae. The latex collected from its stem bark is used for several purposes including anti-inflammatory properties and presents among its bioactive constituents the pentacyclic triterpene lupeol. The objective of the present work was to study in vivo and in vitro the lupeol acetate (LA) isolated from the plant latex, in several models of inflammation.

METHODS

Male Swiss mice (25-30 g, 6-24 animals per group) were administered with LA, 30 min before the test initiation. In the evaluation of analgesic activity the formalin test was used. The anti-inflammatory activity was evaluated by the following tests: paw edema induced by carrageenan and dextran, and the carrageenan-induced neutrophil migration into peritoneal cavities. Furthermore, the effect of LA on the myeloperoxidase release (MPO, an inflammation biomarker) from human neutrophils was also determined, as well as its antioxidant potential by the DPPH assay.

RESULTS

In the formalin test, LA (10, 25 and 50 mg/kg, i.p.) inhibited both the 1st (neurogenic, 0-5 min) and mainly the 2nd (inflammatory, 20-25 min) phase. Naloxone completely reversed the LA effect, indicating the participation of the opioid system. LA also significantly inhibited carrageenan- and dextran-induced paw edemas, as well as the neutrophil migration to the peritoneal cavity evaluated by the carrageenan-induced pleurisia. In this model, the effect of a very low dose of LA (0.1 mg/kg) was potentiated by the same dose of pentoxifylline (PTX), a known TNF-alpha inhibitor. LA (25 and 50 μg/ml) was also very effective in inhibiting MPO released from stimulated human neutrophils, and significantly decreased the number of cells expressing iNOS activity in the paw of mice submitted to carrageenan-induced edema, suggesting a drug involvement with the NO system.

CONCLUSIONS

The anti-inflammatory effect of LA probably involves the opioid system, as indicated by the complete blockade of the opioid antagonist naloxone. Furthermore, the LA effect was potentiated by PTX (a TNF-alpha inhibitor). LA also decreased the number of iNOS cells, suggesting the participation of pro-inflammatory cytokines and the NO system in the drug action.

Activity of physalin F in a collagen-induced arthritis model

The effects of physalin F (1), a steroid derivative purified from Physalis angulata, were investigated in models of collagen-induced arthritis in DBA/1 mice and allergic airway inflammation in BALB/c mice. Oral treatment with 1 or dexamethasone caused a marked decrease in paw edema and joint inflammation when compared to vehicle-treated arthritic mice. In contrast, treatment with 1 had no effect in mice with allergic airway inflammation caused by ovalbumin immunization, whereas dexamethasone significantly reduced the number of inflammatory cells and eosinophils in the broncoalveolar lavage fluid and in lung sections of challenged mice. To further demonstrate that 1 acts through a mechanism different from that of glucocorticoids, a nuclear translocation assay was performed of the glucocorticoid receptor (GR) using COS-7 cells transfected with a plasmid encoding for a yellow fluorescent protein (YFP)-GR fusion protein. Untreated or treated cells with 1 had YFP staining mainly in the cytoplasm, whereas in dexamethasone-treated cells the YFP staining was concentrated in the nuclei. It is concluded that the mechanism of the immunosuppressive activity of physalin F is distinct from that of the glucocorticoids.

Specific targeting of Wnt/β-catenin signaling in human melanoma cells by a dietary triterpene lupeol

Wingless (Wnt) signaling pathway regulates a variety of cellular processes including proliferation, differentiation, survival, apoptosis and cell motility. Aberrant activation of Wnt/β-catenin pathway has been observed in approximately one-third of melanomas and this subset has very poor prognosis suggesting that targeting Wnt signaling could be a promising strategy against this subtype. Mel 928 and Mel 1241 melanoma cells representative of cells with constitutive activation of Wnt/β-catenin signaling pathway and Mel 1011 representative of cells that lack this pathway were treated with a dietary triterpene lupeol and its effects on growth, proliferation, β-catenin transcriptional activity and Wnt target genes were determined both in vitro and in vivo. Lupeol treatment to Mel 928 and Mel 1241 but not Mel 1011 cells resulted in a dose-dependent (i) decrease in cell viability, (ii) induction of apoptosis, (iii) decrease in colonogenic potential, (iv) decrease in β-catenin transcriptional activity and (v) decrease in the expression of Wnt target genes. Most importantly, lupeol restricted the translocation of β-catenin from the cytoplasm to the nucleus. Lupeol also decreased the growth of Mel 928 but not Mel 1011-derived tumors implanted in the athymic nude mice. The decrease in Mel 928-derived tumor growth was associated with a decrease in the expression of Wnt target genes c-myc, cyclin D1, proliferation markers proliferating cell nuclear antigen and Ki-67 and invasion marker osteopontin. We suggest that lupeol alone or as an adjuvant to current therapies could be developed as an agent for the management of human melanomas harboring constitutive Wnt/β-catenin signaling.

Beta-escin has potent anti-allergic efficacy and reduces allergic airway inflammation

Background

Type I hypersensitivity is characterized by the overreaction of the immune system against otherwise innocuous substances. It manifests as allergic rhinitis, allergic conjunctivitis, allergic asthma or atopic dermatitis if mast cells are activated in the respective organs. In case of systemic mast cell activation, life-threatening anaphylaxis may occur. Currently, type I hypersensitivities are treated either with glucocorticoids, anti-histamines, or mast cell stabilizers. Although these drugs exert a strong anti-allergic effect, their long-term use may be problematic due to their side-effects.

Results

In the course of a routine in vitro screening process, we identified beta-escin as a potentially anti-allergic compound. Here we tested beta-escin in two mouse models to confirm this anti-allergic effect in vivo. In a model of the early phase of allergic reactions, the murine passive cutaneous anaphylaxis model, beta-escin inhibited the effects of mast cell activation and degranulation in the skin and dose-dependently prevented the extravasation of fluids into the tissue. Beta-escin also significantly inhibited the late response after antigen challenge in a lung allergy model with ovalbumin-sensitized mice. Allergic airway inflammation was suppressed, which was exemplified by the reduction of leucocytes, eosinophils, IL-5 and IL-13 in the bronchoalveolar lavage fluid. Histopathological examinations further confirmed the reduced inflammation of the lung tissue. In both models, the inhibitory effect of beta-escin was comparable to the benchmark dexamethasone.

Conclusions

We demonstrated in two independent murine models of type I hypersensitivity that beta-escin has potent anti-allergic properties. These results and the excellent safety profile of beta-escin suggest a therapeutic potential of this compound for a novel treatment of allergic diseases.

The activity of medicinal plants and secondary metabolites on eosinophilic inflammation

Eosinophils are leukocytes that are present in several body compartments and in the blood at relatively low numbers under normal conditions. However, an increase in the number of eosinophils, in the blood or in the tissues, is observed in allergic or parasitic disorders. Although some progress has been made in understanding the development of eosinophil-mediated inflammation in allergic and parasitic diseases, the discovery of new compounds to control eosinophilia has lagged behind other advances. Plant-derived secondary metabolites are the basis for many drugs currently used to treat pathologic conditions, including eosinophilic diseases. Several studies, including our own, have demonstrated that plant extracts and secondary metabolites can reduce eosinophilia and eosinophil recruitment in different experimental animal models. In this review, we summarize these studies and describe the anti-eosinophilic activity of various plant extracts, such as Ginkgo biloba, Allium cepa, and Lafoensia pacari, as well as those of secondary metabolites (compounds isolated from plant extracts), such as quercetin and ellagic acid. In addition, we highlight the medical potential of these plant-derived compounds for treating eosinophil-mediated inflammation, such as asthma and allergy.