Antiallergic Phorbol Ester from the Seeds of Aquilaria malaccensis

Comparative Analysis of Metabolome and Transcriptome in Different Tissue Sites of Aquilaria sinensis (Lour.) Gilg

The resinous stem of Aquilaria sinensis (Lour.) Gilg is the sole legally authorized source of agarwood in China. However, whether other tissue parts can be potential substitutes for agarwood requires further investigation. In this study, we conducted metabolic analysis and transcriptome sequencing of six distinct tissues (root, stem, leaf, seed, husk, and callus) of A. sinensis to investigate the variations in metabolite distribution characteristics and transcriptome data across different tissues. A total of 331 differential metabolites were identified by chromatography-mass spectrometry (GC-MS), of which 22.96% were terpenoids. The differentially expressed genes (DEGs) in RNA sequencing were enriched in sesquiterpene synthesis via the mevalonate pathway. The present study establishes a solid foundation for exploring potential alternatives to agarwood.

Synthesis and anti-HIV activities of phorbol derivatives

In this study, 37 derivatives of phorbol esters were synthesized and their anti-HIV-1 activities evaluated, building upon our previous synthesis of 51 phorbol derivatives. 12-Para-electron-acceptor-trans-cinnamoyl-13-decanoyl phorbol derivatives stood out, demonstrating remarkable anti-HIV-1 activities and inhibitory effects on syncytia formation. These derivatives exhibited a higher safety index compared with the positive control drug. Among them, 12-(trans-4-fluorocinnamoyl)-13-decanoyl phorbol, designated as compound 3c, exhibited the most potent anti-HIV-1 activity (EC50 2.9 nmol·L-1, CC50/EC50 11 117.24) and significantly inhibited the formation of syncytium (EC50 7.0 nmol·L-1, CC50/EC50 4891.43). Moreover, compound 3c is hypothesized to act both as an HIV-1 entry inhibitor and as an HIV-1 reverse transcriptase inhibitor. Isothermal titration calorimetry and molecular docking studies indicated that compound 3c may also function as a natural activator of protein kinase C (PKC). Therefore, compound 3c emerges as a potential candidate for developing new anti-HIV drugs.

Diversity of medicinal plants and their therapeutic usages of Kachin people (Jinghpaw) in the central part of Kachin State, Myanmar

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional medical system plays a major role in healthcare in Kachin State, Myanmar, where long-term political instability persists and conventional healthcare facilities are inadequate. A knowledge of the traditional medicinal plants therefore benefits the Kachin people, yet documentation and records of the uses of these plants are rare. In this study, we attempt to answer the questions on what medicinal plants and how they are used by the Kachin people.

AIM OF THE STUDY

We aimed to document knowledge of the traditional medicinal plants and to identify those most frequently used by the Kachin people.

MATERIALS AND METHODS

Eighty-two informants from eight villages in three townships were interviewed, and their knowledge of medicinal plants was recorded. The reported ailments were classified to the standard categories of the International Classification of Primary Care-2 (ICPC-2) system. Use reports (UR) were employed to evaluate the knowledge consensus of the informants.

RESULTS

We recorded a total of 117 species used as medicinal plants, of which 22 are newly recorded medicinal plant species for Myanmar. The plants belonged to 103 genera in 52 families, and were used to treat a total of 72 ailments from 17 ICPC-2 disease categories. Fabaceae and Lamiaceae were the most highly represented families of medicinal plants, with eleven and eight species used, respectively. The most cited species based on URs were Tinospora cordifolia (Willd.) Hook.f. & Thomson (URs = 39), Oroxylum indicum (L.) Kurz (URs = 28), Aquilaria malaccensis Lam. (URs = 26), Chromolaena odorata (L.) R.M.King & H.Rob. (URs = 24), and Chloranthus elatior Link. (URs = 22). Digestive system disorder was the most prevalent disease category, and was treated with 47 different medicinal plants (URs = 142). Leaves were the most commonly used plant part; decoction was the dominant method of preparation; and oral consumption was the most frequent method of administration.

CONCLUSION

Our study documented a list of 117 medicinal plants and their uses in traditional medicine based on the local knowledge of the Kachin people. The study also identified the five most frequently cited species and found that the plants investigated are used to treat a total of 72 diseases. The 642 therapeutic reports we collected showcase a rich and diverse living knowledge of medicinal plant use by the Kachin people. Moreover, we present 22 new medicinal records, enriching the list of known medicinal plants in Myanmar. This exploratory study has enabled us to assemble the local knowledge of the Kachin people into solid dataset that will allow further scientific validation and will potentially contribute to better integration of medicinal plants into the healthcare provision for Kachin people in Myanmar.

Agarwood essential oil inhalation exerts antianxiety and antidepressant effects via the regulation of Glu/GABA system homeostasis

Depression and anxiety are common diseases that endanger the physical and mental health of individuals. Agarwood incense inhalation has been used as a traditional Chinese medicine for relaxation and to improve sleep for centuries. In a previous study by the authors it was demonstrated that agarwood essential oil (AEO) injection exerted anxiolytic and antidepressant effects. Therefore the present study further investigated the anxiolytic and antidepressant effects of AEO inhalation on anxiolytic mice induced by M-chlorophenylpiperazine and depressive mice induced by chronic unpredictable mild stress. The results demonstrated that AEO exerted a significant anxiolytic effect, whereby autonomous movements were inhibited during the light dark exploration test and open field test. Furthermore, the tail suspension test and the forced swimming test demonstrated that AEO also exerted an antidepressant effect, whereby the immobility times were decreased. Moreover, AEO was determined to increase the levels of 5-hydroxytryptamine, γ-aminobutyric acid (GABA) A receptor (GABA_A) and glutamate (Glu) in anxiolytic mice and inhibit the levels of GABA_A and Glu in depressive mice. Further investigations into how AEO affected the Glu/GABA system demonstrated that AEO markedly increased the protein expression levels of GABA transaminase (GABAT), glutamate metabotropic receptor 5 (GRM5), glutamate ionotropic receptor AMPA type subunit 1 (GluR1) and vesicular glutamate transporter 1 (VGluT1). Furthermore, AEO reduced the expression levels of GABAT, glutamate ionotropic receptor NMDA type subunit 2B and GRM5, and enhanced the expression levels of GluR1 and VGluT1. These results demonstrated that AEO potentially possesses antianxiety and antidepressant properties. The present study determined that the mechanism was related to the regulation of Glu/GABA neurotransmitter system homeostasis.

Agarwood-The Fragrant Molecules of a Wounded Tree

Agarwood, popularly known as oudh or gaharu, is a fragrant resinous wood of high commercial value, traded worldwide and primarily used for its distinctive fragrance in incense, perfumes, and medicine. This fragrant wood is created when Aquilaria trees are wounded and infected by fungi, producing resin as a defense mechanism. The depletion of natural agarwood caused by overharvesting amidst increasing demand has caused this fragrant defensive resin of endangered Aquilaria to become a rare and valuable commodity. Given that instances of natural infection are quite low, artificial induction, including biological inoculation, is being conducted to induce agarwood formation. A long-term investigation could unravel insights contributing toward Aquilaria being sustainably cultivated. This review will look at the different methods of induction, including physical, chemical, and biological, and compare the production, yield, and quality of such treatments with naturally formed agarwood. Pharmaceutical properties and medicinal benefits of fragrance-associated compounds such as chromones and terpenoids are also discussed.

Anti-Inflammatory and Antimicrobial Volatile Oils: Fennel and Cumin Inhibit Neutrophilic Inflammation via Regulating Calcium and MAPKs

Neutrophilic inflammatory diseases, such as chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS), or psoriasis, exert a huge burden on the global health system due to the lack of safe and effective treatments. Volatile oils from terrestrial plants showed impressive therapeutic effects against disorders of the skin, digestive system, lungs, liver, metabolism, and nervous system. However, their effect on the immune system and neutrophil function is still elusive. Fennel, cumin, marjoram, lavender, caraway, and anise are the common nutraceuticals that are widely used in the Mediterranean diet. The volatile oils of these herbs were screened for various biological activities, including anti-inflammatory, anti-allergic, antimicrobial, and antiviral effects. Several oils showed anti-inflammatory and antimicrobial potential. Fennel (Foeniculum vulgare) and cumin (Cuminum cyminum) fruits' volatile oils significantly suppressed the activation of human neutrophils, including respiratory burst and the degranulation induced by formyl peptide receptor agonists fMLF/CB and MMK1 in the human neutrophils (IC₅₀, 3.8–17.2 µg/ml). The cytotoxic effect and free-radical scavenging effects (ABTS, DPPH) of these oils did not account for the observed effects. Both fennel and cumin volatile oils significantly shortened calcium influx recovery time and inhibited phosphorylation of mitogen-activated protein kinases (p38, JNK, and ERK) expression. The gas chromatography–mass spectrometry analysis of these oils revealed the presence of estragole and cuminaldehyde as the major components of fennel and cumin volatile oils, respectively. Our findings suggested that cumin and fennel, common in the Mediterranean diet, hold the potential to be applied for the treatment of neutrophilic inflammatory diseases.

Anti-Inflammatory, Antiallergic, and COVID-19 Main Protease (Mpro) Inhibitory Activities of Butenolides from a Marine-Derived Fungus Aspergillus terreus

In December 2020, the U.K. authorities reported to the World Health Organization (WHO) that a new COVID-19 variant, considered to be a variant under investigation from December 2020 (VUI-202012/01), was identified through viral genomic sequencing. Although several other mutants were previously reported, VUI-202012/01 proved to be about 70% more transmissible. Hence, the usefulness and effectiveness of the newly U.S. Food and Drug Administration (FDA)-approved COVID-19 vaccines against these new variants are doubtfully questioned. As a result of these unexpected mutants from COVID-19 and due to lack of time, much research interest is directed toward assessing secondary metabolites as potential candidates for developing lead pharmaceuticals. In this study, a marine-derived fungus Aspergillus terreus was investigated, affording two butenolide derivatives, butyrolactones I (1) and III (2), a meroterpenoid, terretonin (3), and 4-hydroxy-3-(3-methylbut-2-enyl)benzaldehyde (4). Chemical structures were unambiguously determined based on mass spectrometry and extensive 1D/2D NMR analyses experiments. Compounds (1-4) were assessed for their in vitro anti-inflammatory, antiallergic, and in silico COVID-19 main protease (Mpro) and elastase inhibitory activities. Among the tested compounds, only 1 revealed significant activities comparable to or even more potent than respective standard drugs, which makes butyrolactone I (1) a potential lead entity for developing a new remedy to treat and/or control the currently devastating and deadly effects of COVID-19 pandemic and elastase-related inflammatory complications.

Natural products in agarwood and Aquilaria plants: chemistry, biological activities and biosynthesis

Covering: Up to the end of 2019.Agarwood is a resinous portion of Aquilaria trees, which is formed in response to environmental stress factors such as physical injury or microbial attack. It is very sought-after among the natural incenses, as well as for its medicinal properties in traditional Chinese and Ayurvedic medicine. Interestingly, the chemical constituents of agarwood and healthy Aquilaria trees are quite different. Sesquiterpenes and 2-(2-phenethyl)chromones with diverse scaffolds commonly accumulate in agarwood. Similar structures have rarely been reported from the original trees that mainly contain flavonoids, benzophenones, xanthones, lignans, simple phenolic compounds, megastigmanes, diterpenoids, triterpenoids, steroids, alkaloids, etc. This review summarizes the chemical constituents and biological activities both in agarwood and Aquilaria trees, and their biosynthesis is discussed in order to give a comprehensive overview of the research progress on agarwood.

Anti-inflammatory, hepatoprotective and antioxidant activity of ellagitannin isolated from Melaleuca styphelioides

Ellagitannins have a marked antioxidant effect and can prevent liver injury induced by free radicals. An undescribed ellagitannin named styphelioidin was isolated from Melaleuca styphelioides Sm. The structure of styphelioidin was elucidated by using various spectroscopic methods. The hepatoprotective activity of styphelioidin (25, 50, and 100 μM) was tested using the CCl₄-challenged HepG2 cell model by measuring alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in HepG2 cells treated with styphelioidin for 1 h followed by 40 mM CCl₄. Glutathione (GSH), superoxide dismutase activity (SOD) and lipid peroxidation (MDA) were evaluated to determine the mechanisms of the hepatoprotective activity. Styphelioidin significantly reduced the levels of ALT, AST, and MDA at all tested concentrations. Moreover, it conferred a marked increase in the GSH levels and the SOD activity compared to the CCl₄-treated groups. Styphelioidin also exerted DPPH· radical-scavenging effects with an IC₅₀ value of 3.67 μM. Results indicated the hepatoprotective therapeutic potential of styphelioidin comparable to silymarin. Moreover, anti-inflammatory activity was assessed and styphelioidin inhibited fMLF/CB-induced elastase release in human neutrophils with IC₅₀ 2.51 μM. Cell-free experiments with human neutrophil elastase indicated a direct enzymatic inhibitory effect of styphelioidin on the enzyme activity (IC₅₀ 2.58 μM). The potential of styphelioidin to interact with human neutrophil elastase binding sites was further confirmed by molecular docking of styphelioidin into human neutrophil elastase crystal structure using AutoDock 4.2. Styphelioidin represents a potent hepatoprotective and antioxidant agent with effects on ALT, AST, MDA, GSH, and SOD comparable to silymarin. The beneficial anti-elastase properties hold the potential for drug development against elastase-related inflammatory diseases. This study highlights a promising natural hepatoprotective and anti-inflammatory candidate derived from M. styphelioides.

Use of Natural Products in Asthma Treatment

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

Anti-inflammatory, antiallergic and COVID-19 protease inhibitory activities of phytochemicals from the Jordanian hawksbeard: identification, structure–activity relationships, molecular modeling and impact on its folk medicinal uses

On Wednesday 11th March, 2020, the world health organization (WHO) announced novel coronavirus (COVID-19, also called SARS-CoV-2) as a pandemic.

Chemical Constituents of Root Barks of Gnidia involucrata and Evaluation for Antibacterial and Antioxidant Activities

The genus Gnidia, with species close to 152, is traditionally used to treat wide ranges of ailments in humans and animals. Gnidia involucrata is one of the species found in Ethiopia and traditionally used as a laxative, antirheumatic agent, insecticide, antibacterial agent, and antimalarial agent. In view of its traditional use, the root bark was sequentially extracted with n-hexane, EtOAc, and MeOH to afford 0.78%, 4%, and 6% crude extracts, respectively. The chromatographic separation of the EtOAc extract using silica gel column chromatography yielded three pure compounds: tetratriacontanyl caffeate (1), 12-O-dodeca-2,4-dienoylphorbol-13-acetate (2), and naringenin (3). This is the first report of the isolation of 1 and its kind from the genus and most probably from the Thymelaeaceae family. The structures of these compounds were characterized and identified by NMR and mass spectrometric analyses and comparison with literature data. The EtOAc extract and isolated compounds were assessed for their in vitro antibacterial and antioxidant activities. The EtOAc extract (1.5 mg/mL) showed significant inhibitory activity against S. aureus, E. coli, P. mirabilis, and K. pneumonia bacterial strains with the highest inhibition zone observed against S. aureus (23 mm), which is even greater than that of the reference drug ciprofloxacin (22 mm). However, the inhibition displayed on these bacterial strains for the three pure compounds was marginal with variable degrees of potency between the compounds. The better activity of the crude extract could be due to the synergistic interactions of several phytochemicals present in the extract, which cannot be the case when pure compounds are evaluated alone. The antioxidant activities of the extracts and isolated compounds were evaluated using DPPH and ferric thiocyanate methods. The EtOAc and MeOH extracts and compounds 1 and 2 were found to inhibit the DPPH radical by 70.7, 66.9, 85.8, and 52.8%, respectively. The EtOAc extract and compound 1 inhibited peroxidation of lipids by 84 and 86%, respectively. The radical scavenging displayed by compound 1 was significant compared with that displayed by ascorbic acid, indicating the strong antilipid peroxidation potential of the extract of root barks of G. involucrata. Therefore, the extracts of the root bark of G. involucrata can be used as a remedy in combating diseases caused by bacteria and free radicals provided that further comprehensive evaluation could be recommended for the conclusive decision on potential candidacy of this plant.

Agarwood Essential Oil Ameliorates Restrain Stress-Induced Anxiety and Depression by Inhibiting HPA Axis Hyperactivity

In our previous investigation, we found that agarwood essential oil (AEO) has a sedative-hypnotic effect. Sedative-hypnotic drugs usually have an anxiolytic effect, where concomitant anxiety and depression are a common comorbidity. Therefore, this study further investigated the anxiolytic and antidepressant effects of AEO using a series of animal behavior tests on a restraint stress-induced mice model. The elevated plus maze (EPM) test, the light dark exploration (LDE) test, and the open field (OF) test demonstrated that AEO has a significant anxiolytic effect. Simultaneously, the tail suspension (TS) test and the forced swimming (FS) test illuminated that AEO has an antidepressant effect with the immobility time decreased. Stress can cause cytokine and nitric oxide (NO) elevation, and further lead to hypothalamic-pituitary-adrenal (HPA) axis hyperactivity. AEO was shown to dose-dependently inhibit the levels of cytokines, including interleukin 1α (IL-1α), IL-1β, and IL-6 in serum, significantly decrease the mRNA level of neural nitric oxide synthase (nNOS) in the cerebral cortex and hippocampus, and inhibit the nNOS protein level in the hippocampus. Concomitant measurements of the HPA axis upstream regulator corticotropin releasing factor (CRF) and its receptor CRFR found that AEO significantly decreases the gene expression of CRF, and significantly inhibits the gene transcription and protein expression of CRFR in the cerebral cortex and hippocampus. Additionally, AEO dose-dependently reduces the concentrations of adrenocorticotropic hormone (ACTH) and corticosterone (CORT) downstream of the HPA axis, as measured by ELISA kits. These results together demonstrate that AEO exerts anxiolytic and antidepressant effects which are related to the inhibition of CRF and hyperactivity of the HPA axis.

Probing the Antiallergic and Anti-inflammatory Activity of Biflavonoids and Dihydroflavonols from Dietes bicolor

Dietes bicolor (Iridaceae) is an ornamental plant used by African local healers to treat diarrhea and dysentery. A new dihydroflavonol, (2R,3R)-3,5,7-trihydroxy-8-methoxyflavanone (1); two known dihydroflavonols, trans-3-hydroxy-5-methoxy-6,7-methylenedioxyflavanone (2) and trans-3-hydroxy-5,7-dimethoxyflavanone (3); the known isoflavone orobol 7,3'-di-O-methyl ether (4); the known biflavones lanaroflavone (5), robustaflavone (6), and amentoflavone (7); and β-sitosterol (8) were isolated from the CH₂Cl₂ fraction of D. bicolor leaves. The extract showed potent activity in antiallergic and anti-inflammatory assays. The structures of the isolates were identified by spectroscopic and spectrometric methods. Compounds 6 and 7 (400 μM) exhibited antiallergic activity by inhibiting antigen-induced β-hexosaminidase release at 45.7% and 46.3%, respectively. Moreover, 6 and 7 exerted anti-inflammatory activity as demonstrated by the inhibition of superoxide anion generation with an IC₅₀ value of 1.0 μM as well as the inhibition of elastase release with IC₅₀ values of 0.45 and 0.75 μM, respectively. The anti-inflammatory activity was further explained by the virtual docking of the isolated compounds to the binding sites in the human neutrophil elastase (HNE) crystal structure using Discovery Studio 2.5. It was concluded that the biflavonoids bind directly to HNE and inhibit its enzymatic activity based on the CDOCKER algorithm. The data provided evidence for the potential use of D. bicolor against certain diseases related to allergy and inflammation.

Chemical Constituents and Pharmacological Activity of Agarwood and Aquilaria Plants

Agarwood, a highly precious non-timber fragrant wood of Aquilaria spp. (Thymelaeaceae), has been widely used in traditional medicine, religious rites, and cultural activities. Due to the inflated demanding and depleted natural resources, the yields of agarwood collected from the wild are shrinking, and the price is constantly rising, which restricts agarwood scientific research and wide application. With the sustainable planting and management of agarwood applied, and especially the artificial-inducing methods being used in China and Southeast Asian countries, agarwood yields are increasing, and the price is becoming more reasonable. Under this condition, illuminating the scientific nature of traditional agarwood application and developing new products and drugs from agarwood have become vitally important. Recently, the phytochemical investigations have achieved fruitful results, and more than 300 compounds have been isolated, including numerous new compounds that might be the characteristic constituents with physiological action. However, no one has focused on the new compounds and presented a summary until now. Alongside phytochemical advances, bioactivity screening and pharmacological investigation have also made a certain progress. Therefore, this review discussed the new compounds isolated after 2010, and summarized the pharmacological progress on agarwood and Aquilaria plants.

Anti-allergic Hydroxy Fatty Acids from Typhonium blumei Explored through ChemGPS-NP

Increasing prevalence of allergic diseases with an inadequate variety of treatment drives forward search for new alternative drugs. Fatty acids, abundant in nature, are regarded as important bioactive compounds and powerful nutrients playing an important role in lipid homeostasis and inflammation. Phytochemical study on Typhonium blumei Nicolson and Sivadasan (Araceae), a folk anti-cancer and anti-inflammatory medicine, yielded four oxygenated fatty acids, 12R-hydroxyoctadec-9Z,13E-dienoic acid methyl ester (1) and 10R-hydroxyoctadec-8E,12Z-dienoic acid methyl ester (2), 9R-hydroxy-10E-octadecenoic acid methyl ester (3), and 12R^*-hydroxy-10E-octadecenoic acid methyl ester (4). Isolated compounds were identified by spectroscopic methods along with GC-MS analysis. Isolated fatty acids together with a series of saturated, unsaturated and oxygenated fatty acids were evaluated for their anti-inflammatory and anti-allergic activities in vitro. Unsaturated (including docosahexaenoic and eicosapentaenoic acids) as well as hydroxylated unsaturated fatty acids exerted strong anti-inflammatory activity in superoxide anion generation (IC₅₀ 2.14-3.73 μM) and elastase release (IC₅₀ 1.26-4.57 μM) assays. On the other hand, in the anti-allergic assays, the unsaturated fatty acids were inactive, while hydroxylated fatty acids showed promising inhibitory activity in A23187- and antigen-induced degranulation assays (e.g., 9S-hydroxy-10E,12Z-octadecadienoic acid, IC₅₀ 92.4 and 49.7 μM, respectively). According to our results, the presence of a hydroxy group in the long chain did not influence the potent anti-inflammatory activity of free unsaturated acids. Nevertheless, hydroxylation of fatty acids (or their methyl esters) seems to be a key factor for the anti-allergic activity observed in the current study. Moreover, ChemGPS-NP was explored to predict the structure-activity relationship of fatty acids. The anti-allergic fatty acids formed different cluster distant from clinically used drugs. The bioactivity of T. blumei, which is historically utilized in folk medicine, might be related to the content of fatty acids and their metabolites.

Inflammation Modulatory Phorbol Esters from the Seeds of Aquilaria malaccensis

The tree Aquilaria malaccensis is a valuable source of agarwood, which is used in herbal medicinal preparations. Phytochemical research on A. malaccensis seeds has led to the isolation of four new phorbol esters (1-4), two known phorbol esters (5, isolated from Nature for the first time, and 6), and two known glycerides (7 and 8). The structures of these isolates were elucidated by means of spectroscopic data interpretation. The inflammation-modulatory activities of the isolates on elastase release and superoxide anion generation in human neutrophils were evaluated. Interestingly, phorbol esters 1, 5, and 6 showed potent inhibitory activity on elastase release in human neutrophils, with IC₅₀ values of 2.7, 0.8, and 2.1 μM, respectively. All isolated phorbol esters exerted enhancing activity on superoxide anion generation. The results indicated that phorbol esters may play a bilateral modulatory role in the processes of inflammation. In addition, the compounds were evaluated for their cytotoxic properties against HepG2 (hepatoma), MDA-MB-231 (breast), and A549 (lung) cancer cells, but all compounds were inactive for all cell lines used (IC₅₀ > 10 μM).

Anti-allergic potential of Typhonium blumei: Inhibition of degranulation via suppression of PI3K/PLCγ2 phosphorylation and calcium influx

BACKGROUND

Typhonium blumei Nicolson & Sivadasan (Araceae) is a traditional Chinese medicinal herb possessing detumescent, detoxifying, and anti-inflammatory activities. It is used in Taiwan as a folk medicine to treat cancer and inflammatory diseases. Typhonium blumei is usually not distinguished from Typhonium roxburghii Schott and they are commonly used interchangeably.

PURPOSE

To evaluate and compare the anti-allergic and anti-inflammatory properties of T. blumei and T. roxburghii, their composition profiles and molecular basis of the anti-allergic effect.

METHODS

The methanolic plant extracts were partitioned with different solvents to obtain the nonpolar fractions. The anti-allergic activity of the nonpolar fractions was assessed by A23187- and antigen-induced degranulation assays using RBL-2H3 mast cells. Several molecular targets were investigated: FcεRI receptor expression by flow cytometry, calcium influx by live cells imaging fluorescent microscopy, cytokines mRNA expression by RT-PCR, and protein expression by Western blotting. The anti-inflammatory activity was evaluated using superoxide anion and elastase release assays in human neutrophils. TLC, NMR and GC-MS analyses were conducted to evaluate the chemical composition of the fractions.

RESULTS

The nonpolar fractions of both Typhonium species showed potent inhibitory activity in A23187-induced degranulation assay in RBL-2H3 cells. They also inhibited superoxide production and elastase release in human neutrophils. T. blumei nonpolar fractions inhibited antigen-induced β-hexosaminidase and histamine release. The nonpolar fractions of T. blumei significantly inhibited calcium influx upon activation with either A23187 or an antigen. The fractions did not affect FcεRI receptor expression, mRNA level of IL-4 and MCP-1 cytokine production or MAPK proteins expression, but did suppress the calcium signaling pathway via PI3K/PLCγ2. The active fractions were rich in fatty acids with palmitic, linoleic and α-linolenic acids identified as the major fatty acids in both plants. The content of omega-3 unsaturated fatty acids was higher in T. roxburghii nonpolar fractions compared to T. blumei.

CONCLUSION

Both species possess potent anti-allergic and anti-inflammatory activities. The inhibition of degranulation in mast cells was attributed to calcium influx modulation. The obtained results support the traditional use of T. blumei in the treatment of inflammatory diseases as well as its substitution with T. roxburghii.