Anti-allergic effects of scoparone on mast cell-mediated allergy model

Scoparone attenuates PD-L1 expression in human breast cancer cells by MKP-3 upregulation

Breast cancer is a frequently occurring malignant tumor that is one of the leading causes of cancer-related deaths in women worldwide. Monoclonal antibodies that block programed cell death 1 (PD-1)/programed cell death ligand 1 (PD-L1) - a typical immune checkpoint - are currently the recommended standard therapies for many advanced and metastatic tumors such as triple-negative breast cancer. However, some patients develop drug resistance, leading to unfavorable treatment outcomes. Therefore, other approaches are required for anticancer treatments, such as downregulation of PD-L1 expression and promotion of degradation of PD-L1. Scoparone (SCO) is a bioactive compound isolated from Artemisia capillaris that exhibits antitumor activity. However, the effect of SCO on PD-L1 expression in cancer has not been confirmed yet. This study aimed to evaluate the role of SCO in PD-L1 expression in breast cancer cells in vitro. Our results show that SCO downregulated PD-L1 expression in a dose-dependent manner, via AKT inhibition. Interestingly, SCO treatment did not alter PTEN expression, but increased the expression of mitogen-activated protein kinase phosphatase-3 (MKP-3). In addition, the SCO-induced decrease in PD-L1 expression was reversed by siRNA-mediated MKP-3 knockdown. Collectively, these findings suggest that SCO inhibited the expression of PD-L1 in breast cancer cells by upregulating MKP-3 expression. Therefore, SCO may serve as an innovative combinatorial agent for cancer immunotherapy.

Photodegradation of the pure and formulated scoparone in liquid solutions: kinetics and mechanism

Scoparone (hereafter SPR) is a prominent candidate of plant-derived acaricide. The photodegradation of the pure SPR was first investigated under different light sources, initial concentrations, pH values, temperatures, organic solvents, aqueous media, and the photolytic characteristics of its formulation in pure water were also studied. The photodegradation rates of pure SPR under different light sources showed the following sequence: 28 W ultraviolet lamp (0.3045 h-1) > 500 W xenon lamp (0.1094 h-1) > 300 W xenon lamp (0.0312 h-1). Under the irradiation of 500 W xenon lamp, the lower initial SPR concentrations, higher pH value, and higher temperatures increased the photodegradation rates of SPR, especially, when the temperature increased higher than 35℃, the degradation rate of SPR increased slowly and maintained at a stable level, the pH and temperatures had small effects on the photodegradation of SPR. The photodegradation rates of pure SPR in organic decreased comparing to in aqueous media. The removal efficiency of 98% SPR technical material (TC) was higher than 5% SPR emulsifiable concentrate (EC) in pure water, indicating that the components present in formulated SPR greatly affected the photodegradation kinetics. Detecting the photoproducts by HPLC/ESI-MS indicated that three main types of reaction including photorearrangement, photohydrolysis, and photooxidation occurred in the photodegradation of SPR at aqueous solution. These results will be helpful for the rational use of SPR and provide a scientific reference for environmental risk evaluation of SPR.

Insight into the mechanism of action of scoparone inhibiting egg development of Tetranychus cinnabarinus Boisduval

Investigating the mechanisms of action of natural bioactive products against pests is a vital strategy to develop novel promising biopesticides. Scoparone, isolated from Artemisia capillaris, exhibited potent oviposition inhibition activity against Tetranychus cinnabarinus (a crop-threatening mite pests with strong fecundity). To explore the underlying mechanism, the vitellogenin (Vg) protein content, and Vg gene expression of mites from three consecutive generations of G0 individuals exposed to scoparone were determined, revealing marked inhibition. This study is the first to explore the egg development defect behaviour of mite pests induced by scoparone. The egg-laying inhibition of mites by scoparone was significantly increased by 47.43% compared with that of the control when TcVg was silenced by RNA interference (RNAi), suggesting that egg-development inhibition of female T. cinnabarinus by scoparone was mediated by low Vg gene expression. Furthermore, scoparone bound to the Vg protein in vitro, and its K_d value was 218.9 μM, implying its potential function in inhibiting the egg development of mites by directly targeting the Vg protein. This study will lay the foundation for the future applications of scoparone as an agrochemical for controlling the strong egg-laying capacity mite pests in agriculture.

Cytokine Storm Syndrome in SARS-CoV-2 Infections: A Functional Role of Mast Cells

Cytokine storm syndrome is a cascade of escalated immune responses disposing the immune system to exhaustion, which might ultimately result in organ failure and fatal respiratory distress. Infection with severe acute respiratory syndrome-coronavirus-2 can result in uncontrolled production of cytokines and eventually the development of cytokine storm syndrome. Mast cells may react to viruses in collaboration with other cells and lung autopsy findings from patients that died from the coronavirus disease that emerged in 2019 (COVID-19) showed accumulation of mast cells in the lungs that was thought to be the cause of pulmonary edema, inflammation, and thrombosis. In this review, we present evidence that a cytokine response by mast cells may initiate inappropriate antiviral immune responses and cause the development of cytokine storm syndrome. We also explore the potential of mast cell activators as adjuvants for COVID-19 vaccines and discuss the medications that target the functions of mast cells and could be of value in the treatment of COVID-19. Recognition of the cytokine storm is crucial for proper treatment of patients and preventing the release of mast cell mediators, as impeding the impacts imposed by these mediators could reduce the severity of COVID-19.

Anti-type I allergic effects of Jing-Fang powder extracts via PI3K/Akt pathway in vitro and in vivo

Jing-Fang powder (Schizonepeta tenuifolia Briq. and Saposhnikovia divaricata (Turcz.) Schischk.) was used to treat chronic bronchitis, asthma and chronic urticaria. Based on the preliminary results of screening research on the antiallergic effective parts of Jing-Fang powder, its ethyl acetate extract fractions (JFEE) and isolate D (JFEE-D) showed the best anti-allergic effect. RBL-2H3 cell activation degranulation model and mice passive cutaneous anaphylaxis (PCA) reaction model were used to investigate the effects and mechanisms of JFEE and JFEE-D on IgE-mediated type I allergic reactions. LC-MS was utilized to determine the composition of JFEE and JFEE-D. We found that JFEE and JFEE-D significantly reduced β-HEX, histamine, IL-4, IL-6 levels in cell supernatants, and improved the degree and morphology of cell degranulation. JFEE and JFEE-D significantly inhibited the increase of ear vascular permeability and abnormal increase of serum IgE, TNF-α, IL-6 levels. JFEE and JFEE-D inhibited mRNA expression of PI3K and Akt and down-regulated protein expression of PI3K, Akt, p-Akt, and PLCγ1 in sensitized RBL-2H3 cells. The combined use of JFEE and JFEE-D with pathway inhibitor Wortmannin revealed synergistic down-regulation of PI3K, Akt, and p-Akt protein expression. The combined use of pathway agonist IGF-1, JFEE and JFEE-D down-regulated increase of p-Akt/Akt protein expression. Moreover, JFEE and JFEE-D significantly inhibited protein expression of PI3K, p-Akt and PLCγ1 in PCA model mice. These results show that JFEE and JFEE-D inhibit type I allergic reactions by inhibiting PI3K/Akt signaling pathway.

Artemisia scoparia and Metabolic Health: Untapped Potential of an Ancient Remedy for Modern Use

Botanicals have a long history of medicinal use for a multitude of ailments, and many modern pharmaceuticals were originally isolated from plants or derived from phytochemicals. Among these, artemisinin, first isolated from Artemisia annua, is the foundation for standard anti-malarial therapies. Plants of the genus Artemisia are among the most common herbal remedies across Asia and Central Europe. The species Artemisia scoparia (SCOPA) is widely used in traditional folk medicine for various liver diseases and inflammatory conditions, as well as for infections, fever, pain, cancer, and diabetes. Modern in vivo and in vitro studies have now investigated SCOPA's effects on these pathologies and its ability to mitigate hepatotoxicity, oxidative stress, obesity, diabetes, and other disease states. This review focuses on the effects of SCOPA that are particularly relevant to metabolic health. Indeed, in recent years, an ethanolic extract of SCOPA has been shown to enhance differentiation of cultured adipocytes and to share some properties of thiazolidinediones (TZDs), a class of insulin-sensitizing agonists of the adipogenic transcription factor PPARγ. In a mouse model of diet-induced obesity, SCOPA diet supplementation lowered fasting insulin and glucose levels, while inducing metabolically favorable changes in adipose tissue and liver. These observations are consistent with many lines of evidence from various tissues and cell types known to contribute to metabolic homeostasis, including immune cells, hepatocytes, and pancreatic beta-cells. Compounds belonging to several classes of phytochemicals have been implicated in these effects, and we provide an overview of these bioactives. The ongoing global epidemics of obesity and metabolic disease clearly require novel therapeutic approaches. While the mechanisms involved in SCOPA's effects on metabolic, anti-inflammatory, and oxidative stress pathways are not fully characterized, current data support further investigation of this plant and its bioactives as potential therapeutic agents in obesity-related metabolic dysfunction and many other conditions.

Effect of tyrosinase and caffeic acid crosslinking of turbot parvalbumin on the digestibility, and release of mediators and cytokines from activated RBL-2H3 cells

Turbot can induce allergy in susceptible individuals due to the presence of parvalbumin (PV), a major fish allergen. This study aimed at evaluating the digestibility and the ability of PV to elicit the release of cellular degranulation, following treatment with tyrosinase (PV-Tyr), caffeic acid (PV-CA) and in combination (PV-Tyr/CA), using in vitro digestion and RBL-2H3 (passive rat basophil leukemia) cell line. The digestion assay products revealed that the stability of PV in simulated gastric fluid (SGF) was stronger, while in simulated intestinal fluid (SIF) was rather weak. Western blot analysis revealed that the IgG-binding abilities of the cross-linked PV were markedly reduced. Moreover, crosslinking hampered the release of cellular degranulation process in RBL-2H3 cell lines. PV-Tyr/CA showed highly significant reduction in the release rate of β-hexosaminidase (66.02%), histamine (35.01%), tryptase (29.25%), cysteinyl leukotrienes (29.72%), prostaglandin D₂ (34.96%), IL-4 (43.99%) and IL-13 (38.93%) and shown potential in developing hypoallergenic fish products.

GC-MS explores the health care components in the extract of Pterocarpus pedatus Pierre

Pterocarpus a high-end, expensive furniture materials collectively. Pterocarpus and Pterocarpus products have a certain human health function. Therefore, this paper to Pterocarpus pedatus Pierre as an example, to study its extract on human health beneficial health care ingredients. FT-IR analysis showed that the infrared transmittance of Pterocarpus pedatus Pierre powder after ethanol/benzene extraction was the highest in the infrared spectrum of 400 cm^-1-800 cm^-1, 2750 cm^-1-3200 cm^-1 wave number. In the 1750 cm^-1-2400 cm^-1 wave segment, methanol, ethyl acetate and ethanol/benzene after the extraction of Pterocarpus pedatus Pierre powder infrared transmittance increased values are basically the same. GC-MS analysis, the health care ingredients in the Pterocarpus pedatus Pierre have cough and phlegm, heat detoxification, enhance human immunity, analgesic and anti-inflammatory and so on. Among them, Homopterocarpin is excellent in inhibiting and killing cancer cell activity; Cryptomeridiol is a natural product with anti-Alzheimer's disease and antispasmodic nature, and its medicinal value is remarkable. Scoparone has a wide range of pharmacological values.

Scoparone prevents IL-1β-induced inflammatory response in human osteoarthritis chondrocytes through the PI3K/Akt/NF-κB pathway

Osteoarthritis (OA) is a degenerative joint disease that is commonly accompanied by inflammation. Scoparone is a biologically active constituent isolated from Artemisia capillaris and possesses anti-inflammatory activity. However, the effect of scoparone on inflammatory response in OA has not been authenticated. The aim of this study was to evaluate the role of scoparone in OA in vitro. Our results showed that IL-1β treatment significantly inhibited the cell viability of chondrocytes, whereas the inhibition effect was attenuated by scoparone in a dose-dependent manner. IL-1β also efficiently induced the production of nitric oxide (NO), prostaglandin E2 (PGE2), MMP-3, MMP-13, ADAMTS-4 and ADAMTS-5 in chondrocytes. However, scoparone dose-dependently suppressed the induction. In addition, scoparone repressed IL-1β-induced the expression of iNOS and COX-2 in chondrocytes. Furthermore, the activation of the PI3K/Akt/NF-κB pathway induced by IL-1β was diminished by scoparone treatment. Taken together, these findings indicated that scoparone inhibited the expression of inflammatory mediators in IL-1β-induced chondrocytes via regulating the PI3K/Akt/NF-κB pathway. Thus, scoparone may be used as a new therapeutic agent for the treatment of OA.

Jacareubin inhibits FcεRI-induced extracellular calcium entry and production of reactive oxygen species required for anaphylactic degranulation of mast cells

Mast cells (MCs) are important effectors in allergic reactions since they produce a number of pre-formed and de novo synthesized pro-inflammatory compounds in response to the high affinity IgE receptor (FcεRI) crosslinking. IgE/Antigen-dependent degranulation and cytokine synthesis in MCs have been recognized as relevant pharmacological targets for the control of deleterious inflammatory reactions. Despite the relevance of allergic diseases worldwide, efficient pharmacological control of mast cell degranulation has been elusive. In this work, the xanthone jacareubin was isolated from the heartwood of the tropical tree Callophyllum brasilense, and its tridimensional structure was determined for the first time by X-ray diffraction. Also, its effects on the main activation parameters of bone marrow-derived mast cells (BMMCs) were evaluated. Jacareubin inhibited IgE/Ag-induced degranulation in a dose-response manner with an IC₅₀ = 46 nM. It also blocked extracellular calcium influx triggered by IgE/Ag complexes and by the SERCA ATPase inhibitor thapsigargin (Thap). Inhibition of calcium entry correlated with a blockage on the reactive oxygen species (ROS) accumulation. Antioxidant capacity of jacareubin was higher than the showed by α-tocopherol and caffeic acid, but similar to trolox. Jacareubin shown inhibitory actions on xanthine oxidase, but not on NADPH oxidase (NOX) activities. In vivo, jacareubin inhibited passive anaphylactic reactions and TPA-induced edema in mice. Our data demonstrate that jacareubin is a potent natural compound able to inhibit anaphylactic degranualtion in mast cells by blunting FcεRI-induced calcium flux needed for secretion of granule content, and suggest that xanthones could be efficient anti-oxidant, antiallergic, and antiinflammatory molecules.

Chinese Medicines in the Treatment of Prostate Cancer: From Formulas to Extracts and Compounds

In order to fully understand the progresses and achievements in Chinese medicines for the treatment of prostate cancer, we summarize all the available reports on formulas, extracts, and compounds of Chinese medicines against prostate cancer. A number of clinical trials verified that traditional Chinese formulas had some unique advantages in the treatment of prostate cancer. Many Chinese medicine extracts could protect against prostate cancer, and many compounds isolated from Chinese traditional medicines showed a clear anti-prostate cancer effect. However, Chinese medicines are facing many problems regarding their multicomponent nature, complicated mechanisms of action, and high doses required for therapy. Herein, we review the functions of Chinese medicines in prostate cancer and focus on their mechanisms. The review will deepen the understanding of Chinese medicines potential in the anti-prostate cancer field. In addition, we put forward a question concerning the current research on Chinese medicines: in order to better illustrate that Chinese medicines can be used in the clinical treatment of prostate cancer, should our research focus on formulas, extracts, or compounds?

Systems Pharmacological Approach of Pulsatillae Radix on Treating Crohn's Disease

In East Asian traditional medicine, Pulsatillae Radix (PR) is widely used to treat amoebic dysentery and renowned for its anti-inflammatory effects. This study aimed to confirm evidence regarding the potential therapeutic effect of PR on Crohn's disease using a system network level based in silico approach. Study results showed that the compounds in PR are highly connected to Crohn's disease related pathways, biological processes, and organs, and these findings were confirmed by compound-target network, target-pathway network, and gene ontology analysis. Most compounds in PR have been reported to possess anti-inflammatory, anticancer, and antioxidant effects, and we found that these compounds interact with multiple targets in a synergetic way. Furthermore, the mRNA expressions of genes targeted by PR are elevated significantly in immunity-related organ tissues, small intestine, and colon. Our results suggest that the anti-inflammatory and repair and immune system enhancing effects of PR might have therapeutic impact on Crohn's disease.

Cornuside inhibits mast cell-mediated allergic response by down-regulating MAPK and NF-κB signaling pathways

AIMS

The present study is to investigate the effect of cornuside on mast cell-mediated allergic response, as well as its possible mechanisms of action.

METHODS

To test the anti-allergic effects of cornuside in vivo, local extravasation was induced by local injection of anti-dinitrophenyl immunoglobulin E (IgE) followed by intravenous antigenic challenge in passive cutaneous anaphylaxis model rats. Mast cell viability was determined using MTT assay. Histamine content from rat peritoneal mast cells was measured by the radioenzymatic method. To investigate the mechanisms by which cornuside affects the reduction of histamine release, the levels of calcium uptake were measured. To examine whether cornuside affects the expression of pro-inflammatory cytokines, Western blotting and ELISA were carried out.

RESULTS

Oral administration of cornuside inhibited passive cutaneous anaphylaxis in rats. Presence of cornuside attenuated IgE-induced histamine release from rat peritoneal mast cells. The inhibitory effect of cornuside on histamine release was mediated by the modulation of intracellular calcium. In addition, cornuside decreased phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187-stimulated production and secretion of pro-inflammatory cytokines such as TNF-α and IL-6 in human mast cells. The inhibitory effect of cornuside on pro-inflammatory cytokines was dependent on nuclear factor-κB and p38 mitogen-activated protein kinase.

CONCLUSIONS

The present study provides evidence that cornuside inhibits mast cell-derived inflammatory allergic reactions by blocking histamine release and pro-inflammatory cytokine expression. Furthermore, in vivo and in vitro anti-allergic effects of cornuside suggest a possible therapeutic application of this agent in inflammatory allergic diseases.

Gastroprotective efficacy and safety evaluation of scoparone derivatives on experimentally induced gastric lesions in rodents

This study investigated the gastroprotective efficacy of synthesized scoparone derivatives on experimentally induced gastritis and their toxicological safety. Six scoparone derivatives were synthesized and screened for gastroprotective activities against HCl/ethanol- and indomethacin-induced gastric ulcers in rats. Among these compounds, 5,6,7-trimethoxycoumarin and 6,7,8-trimethoxycoumarin were found to have gastroprotective activity greater than the standard drug rebamipide; 6-methoxy-7,8-methylenedioxycoumarin, 6-methoxy-7,8-(1-methoxy)-methylenedioxycoumarin, 6,7-methylenedioxycoumarin, and 6,7-(1-methoxy)-methylenedioxycoumarin were found to be equipotent or less potent that of rebamipide. Pharmacological studies suggest that the presence of a methoxy group at position C-5 or C-8 of the scoparone's phenyl ring significantly improves gastroprotective activity, whereas the presence of a dioxolane ring at C-6, C-7, or C-8 was found to have decreased activity. In order to assess toxicological safety, two of the potent gastroprotective scoparone derivatives-5,6,7-trimethoxycoumarin and 6,7,8-trimethoxycoumarin-were examined for their acute toxicity in mice as well as their effect on cytochrome P450 (CYP) enzyme activity. These two compounds showed low acute oral toxicity in adult male and female mice, and caused minimal changes to CYP3A4 and CYP2C9 enzyme activity. These results indicate that compared to other scoparone derivatives, 5,6,7-trimethoxycoumarin and 6,7,8-trimethoxycoumarin can improve gastroprotective effects, and they have low toxicity and minimal effects on drug-metabolizing enzymes.

Scoparone attenuates RANKL-induced osteoclastic differentiation through controlling reactive oxygen species production and scavenging

Scoparone, one of the bioactive components of Artemisia capillaris Thunb, has various biological properties including immunosuppressive, hepatoprotective, anti-allergic, anti-inflammatory, and antioxidant effects. This study aims at evaluating the anti-osteoporotic effect of scoparone and its underlying mechanism in vitro. Scoparone demonstrated potent cellular antioxidant capacity. It was also found that scoparone inhibited the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation and suppressed cathepsin K and tartrate-resistant acid phosphatase (TRAP) expression via c-jun N-terminal kinase (JNK)/extracellular signal-regulated kinase (ERK)/p38-mediated c-Fos-nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) signaling pathway. During osteoclast differentiation, the production of general reactive oxygen species (ROS) and superoxide anions was dose-dependently attenuated by scoparone. In addition, scoparone diminished NADPH (nicotinamide adenine dinucleotide phosphate) oxidase 1 (Nox1) expression and activation via the tumor necrosis factor receptor-associated factor 6 (TRAF6)-cSrc-phosphatidylinositol 3-kinase (PI3k) signaling pathway and prevented the disruption of mitochondrial electron transport chain system. Furthermore, scoparone augmented the expression of superoxide dismutase 1 (SOD1) and catalase (CAT). The overall results indicate that the inhibitory effect of scoparone on RANKL-induced osteoclast differentiation is attributed to the suppressive effect on ROS and superoxide anion production by inhibiting Nox1 expression and activation and protecting the mitochondrial electron transport chain system and the scavenging effect of ROS resulting from elevated SOD1 and CAT expression.

Twenty-first century mast cell stabilizers

Mast cell stabilizing drugs inhibit the release of allergic mediators from mast cells and are used clinically to prevent allergic reactions to common allergens. Despite the relative success of the most commonly prescribed mast cell stabilizer, disodium cromoglycate, in use for the preventative treatment of bronchial asthma, allergic conjunctivitis and vernal keratoconjunctivitis, there still remains an urgent need to design new substances that are less expensive and require less frequent dosing schedules. In this regard, recent developments towards the discovery of the next generation of mast cell stabilizing drugs has included studies on substances isolated from natural sources, biological, newly synthesized compounds and drugs licensed for other indications. The diversity of natural products evaluated range from simple phenols, alkaloids, terpenes to simple amino acids. While in some cases their precise mode of action remains unknown it has nevertheless sparked interest in the development of synthetic derivatives with improved pharmacological properties. Within the purely synthetic class of inhibitors, particular attention has been devoted to the inhibition of important signalling molecules including spleen TK and JAK3. The statin class of cholesterol-lowering drugs as well as nilotinib, a TK inhibitor, are just some examples of clinically used drugs that have been evaluated for their anti-allergic properties. Here, we examine each approach under investigation, summarize the test data generated and offer suggestions for further preclinical evaluation before their therapeutic potential can be realized.

Recent Studies and Progression of Yin Chen Hao ( Yīn Chén Hāo), a Long-term Used Traditional Chinese Medicine

Yin Chen Hao (Artemisia capillaris Thunb; 茵陳蒿 Yīn Chén Hāo) is a traditional Chinese medicine for treating hepatic disorders. This review provides recent pharmacological studies of Yin Chen Hao as well as some chemical constituents isolated from Yin Chen.

Semisynthesis, ex vivo evaluation, and SAR studies of coumarin derivatives as potential antiasthmatic drugs

Asthma is a chronic inflammatory disorder that causes contraction in the smooth muscle of the airway and blocking of airflow. Reversal the contractile process is a strategy for the search of new drugs that could be used for the treatment of asthma. This work reports the semisynthesis, ex vivo relaxing evaluation and SAR studies of a series of 18 coumarins. The results pointed that the ether derivatives 1-3, 7-9 and 13-15 showed the best activity (Emax = 100%), where compound 2 (42 μM) was the most potent, being 4-times more active than theophylline (positive control). The ether homologation (methyl, ethyl and propyl) in position 7 or positions 6 and 7 of coumarins lead to relaxing effect, meanwhile formation of esters generated less active compounds than ethers. The SAR analysis showed that it is necessary the presence of two small ether groups and the methyl group at position 4 (site 3) encourage biological activity through soft hydrophobic changes in the molecule, without drastically affecting the cLogP.

Antioxidant and intestinal anti-inflammatory effects of plant-derived coumarin derivatives

BACKGROUND

Coumarins, also known as benzopyrones, are plant-derived products with several pharmacological properties, including antioxidant and anti-inflammatory activities. Based on the wide distribution of coumarin derivatives in plant-based foods and beverages in the human diet, our objective was to evaluate both the antioxidant and intestinal anti-inflammatory activities of six coumarin derivatives of plant origin (scopoletin, scoparone, fraxetin, 4-methyl-umbeliferone, esculin and daphnetin) to verify if potential intestinal anti-inflammatory activity was related to antioxidant properties.

METHODS

Intestinal inflammation was induced by intracolonic instillation of TNBS in rats. The animals were treated with coumarins by oral route. The animals were killed 48 h after colitis induction. The colonic segments were obtained after laparotomy and macroscopic and biochemical parameters (determination of glutathione level and myeloperoxidase and alkaline phosphatase activities) were evaluated. The antioxidant properties of these coumarins were examined by lipid peroxidation and DPPH assays.

RESULTS

Treatment with esculin, scoparone and daphnetin produced the best protective effects. All coumarin derivatives showed antioxidant activity in the DPPH assay, while daphnetin and fraxetin also showed antioxidant activity by inhibiting lipid peroxidation. Coumarins, except 4-methyl-umbeliferone, also showed antioxidant activity through the counteraction of glutathione levels or through the inhibition of myeloperoxidase activity.

DISCUSSION

The intestinal anti-inflammatory activity of coumarin derivatives were related to their antioxidant properties, suggesting that consumption of coumarins and/or foods rich in coumarin derivatives, particularly daphnetin, esculin and scoparone, could prevent intestinal inflammatory disease.

Different susceptibilities of Leishmania spp. promastigotes to the Annona muricata acetogenins annonacinone and corossolone, and the Platymiscium floribundum coumarin scoparone

Leishmaniasis is a zoonotic disease that can manifest itself in visceral and cutaneous form. The aim of this study was to search for new leishmanicidal compounds. Preliminarily, Artemia salina assay was applied to compounds from two plants found in Northeastern Brazil, Platymiscium floribundum and Annona muricata. Then these compounds were tested against three Leishmania species (Leishmania donovani, Leishmania mexicana and Leishmania major). A screening assay using luciferase-expressing promastigote form were used to measure the viability of promastigote One coumarin, scoparone, isolated from P. floribundum and two acetogenins, annonacinone and corossolone isolated from A. muricata showed leishmanicidal activity in all species tested. Nevertheless, Leishmania species indicated different susceptibilities in relation to the tested compounds: L. mexicana was more sensitive to scoparone followed by L. major and L. donovani. The three species presented similar inhibition to corossolone and annonacinone. Acetogenin annonacinone (EC(50)=6.72-8.00 μg/mL) indicated high leishmanicidal activity; corossolone (EC(50)=16.14-18.73 μg/mL) and scoparone (EC(50)=9.11-27.51 μg/mL) moderate activity. A. saline larvae were less sensitive to the coumarin scoparone and acetogenin corossolone was the most toxic. In conclusion, the leishmanicidal activity demonstrated by the coumarin and acetogenins indicate these compounds for further studies aiming the development of new leishmanicidal agents.