Anti-Leishmania activity of essential oil of Myracrodruon urundeuva (Engl.) Fr. All.: Composition, cytotoxity and possible mechanisms of action

Amburana cearensis (Cumaru) and Its Active Principles as Source of Anti-Leishmania Drugs: Immunomodulatory Activity of Coumarin (1,2-Benzopyrone)

Background/Objectives: In Brazil, Leishmania braziliensis is the main etiological agent of cutaneous leishmaniasis and represents an important public health problem. The actual pharmacotherapy of leishmaniasis has several disadvantages, making the development of new therapeutic options essential. The present study aimed to carry out the bioprospecting and selection of products of Amburana cearensis, including extracts and active principles with a leishmanicidal effect and to evaluate its possible mechanism of action. Methods: A dry extract of A. cearensis (DEAC) was characterized by HPLC, with the following active markers: coumarin (CM), amburoside A (AMR), and vanillic acid (VA). The leishmanicidal effect of DEAC was assessed, and the in vitro inhibitory action of the phenolic fraction, including CM, AMR, and VA, on promastigote and amastigote forms were determined. Results: CM showed the best reductions (maximal inhibition: 57%) of the promastigote form of L. braziliensis, followed by the plant extract (40% inhibition) and other test drugs (maximal reduction: 29%). The treatment of macrophages infected by L. brasiliensis with CM (10 μg/mL) reduced the intracellular parasite load (amastigote form, maximal reduction: 50%), increased the production of nitric oxide, TNF-α, IL-12, and IL-10, and decreased the production of IL-4. These effects were not related to cytotoxicity (MTT test). Glucantime (4 mg/mL, standard drug) reduced the amastigote form by 65%. Conclusions: CM showed promising leishmanicidal activity against both forms of L. brasiliensis, and this effect seems to be associated, at least in part, to its immunomodulatory action by tilting the Th1/Th2 imbalance in favor of Th1.

Enhanced Nanogel Formulation Combining the Natural Photosensitizer Curcumin and Pectis brevipedunculata (Asteraceae) Essential Oil for Synergistic Daylight Photodynamic Therapy in Leishmaniasis Treatment

Background/Objectives: Neglected tropical diseases (NTDs), such as leishmaniasis, remain a global health challenge due to limited therapeutic options and rising drug resistance. In this study, we developed an advanced nanogel formulation incorporating curcumin (CUR) and Pectis brevipedunculata essential oil (EOPb) within an F127/Carbopol 974P matrix to enhance bioavailability and therapeutic efficacy against Leishmania (Leishmania) amazonensis (LLa) promastigotes. Methods: The chemical profile of EOPb was determined through GC-MS and NMR analyses, confirming the presence of key bioactive monoterpenes such as neral, geranial, α-pinene, and limonene. The nanogel formulation (nGPC) was optimized to ensure thermosensitivity, and stability, exhibiting a sol-gel transition at physiological temperatures. Rheological analysis revealed that nGPC exhibited Newtonian behavior at 5 °C, transitioning to shear-thinning and thixotropic characteristics at 25 and 32 °C, respectively. This behavior facilitates its application and controlled drug release, making it ideal for topical formulations. Dynamic light scattering (DLS) analysis demonstrated that nGPC maintained a stable nanoscale structure with hydrodynamic radius below 300 nm, while Fourier-transform infrared spectroscopy (FTIR) confirmed strong molecular interactions between EOPb, CUR, and the polymer matrix. Biological assays demonstrated that nGPC significantly enhanced anti-promastigote activity compared to free CUR and OEPb. Results: At the highest tested concentration (50 μg/mL EOPb and 17.5 μg/mL CUR) nGPC induced over 88% mortality in LLa promastigotes across 24, 48, and 72 h, indicating sustained efficacy. Even at lower concentrations, nGPC retained dose-dependent activity, suggesting a synergistic effect between CUR and EOPb. These findings highlight the potential of nGPC as an innovative nanocarrier for daylight photodynamic therapy (dPDT) in the treatment of leishmaniasis. Future studies will investigate the underlying mechanisms of this synergism and explore the potential application of photodynamic therapy (PDT) to further enhance therapeutic outcomes.

The effect of cannabis-derived terpenes on alveolar macrophage function

Cannabis sativa (marijuana) is used by millions of people around the world. C. sativa produces hundreds of secondary metabolites including cannabinoids, flavones and terpenes. Terpenes are a broad class of organic compounds that give cannabis and other plants its aroma. Previous studies have demonstrated that terpenes may exert anti-inflammatory properties on immune cells. However, it is not known whether terpenes derived from cannabis alone or in combination with the cannabinoid ∆9-THC impacts the function of alveolar macrophages, a specialized pulmonary innate immune cell that is important in host defense against pathogens. Therefore, we investigated the immunomodulatory properties of two commercially-available cannabis terpene mixtures on the function of MH-S cells, a murine alveolar macrophage cell line. MH-S cells were exposed to terpene mixtures at sublethal doses and to the bacterial product lipopolysaccharide (LPS). We measured inflammatory cytokine levels using qRT-PCR and multiplex ELISA, as well as phagocytosis of opsonized IgG-coated beads or mCherry-expressing Escherichia coli via flow cytometry. Neither terpene mixture affected inflammatory cytokine production by MH-S cells in response to LPS. Terpenes increased MH-S cell uptake of opsonized beads but had no effect on phagocytosis of E. coli. Addition of ∆9-THC to terpenes did not potentiate cytotoxicity nor phagocytosis. These results suggest that terpenes from cannabis have minimal impact on the function of alveolar macrophages.

Anti-Leishmania amazonensis Activity of Morolic Acid, a Pentacyclic Triterpene with Effects on Innate Immune Response during Macrophage Infection

Leishmaniasis is a group of infectious diseases transmitted to humans during vector bites and caused by protozoans of the genus Leishmania. Conventional therapies face challenges due to their serious side effects, prompting research into new anti-leishmania agents. In this context, we investigated the effectiveness of morolic acid, a pentacyclic triterpene, on L. amazonensis promastigotes and amastigotes. The present study employed the MTT assay, cytokine analysis using optEIATM kits, an H2DCFDA test, and nitric oxide dosage involving nitrite production and Griess reagent. Morolic acid inhibited promastigote and axenic amastigote growth forms at IC50 values of 1.13 µM and 2.74 µM, respectively. For cytotoxicity to macrophages and VERO cells, morolic acid obtained respective CC50 values of 68.61 µM and 82.94 µM. The compound causes damage to the parasite membrane, leading to cellular leakage. In the infection assay, there was a decrease in parasite load, resulting in a CI50 of 2.56 µM. This effect was associated with immunomodulatory activity, altering macrophage structural and cellular parasite elimination mechanisms. Morolic acid proved to be an effective and selective natural compound, making it a strong candidate for future in vivo studies in cutaneous leishmaniasis.

Trypanosoma cruzi Sirtuin 2 as a Relevant Druggable Target: New Inhibitors Developed by Computer-Aided Drug Design

Trypanosoma cruzi, the etiological agent of Chagas disease, relies on finely coordinated epigenetic regulation during the transition between hosts. Herein we targeted the silent information regulator 2 (Sir2) enzyme, a NAD+-dependent class III histone deacetylase, to interfere with the parasites’ cell cycle. A combination of molecular modelling with on-target experimental validation was used to discover new inhibitors from commercially available compound libraries. We selected six inhibitors from the virtual screening, which were validated on the recombinant Sir2 enzyme. The most potent inhibitor (CDMS-01, IC50 = 40 μM) was chosen as a potential lead compound.

In silico and in vitro antileishmanial effects of gamma-terpinene: Multifunctional modes of action

INTRODUCTION

Leishmaniasis denotes a significant health challenge worldwide with no ultimate treatment. The current study investigated the biological effects of gamma-terpinene (GT) on Leishmania major in putative antileishmanial action, cytotoxicity, apoptosis induction, gene expression alteration, antioxidant activity, hemolysis, and ROS generation.

METHODS

GT and meglumine antimoniate (MA) were probed alone and in combination (GT/MA) for their anti-leishmanial potentials using the MTT biochemical colorimetric assay and a model macrophage cell. In addition, their immunomodulatory properties were assessed by analyzing their effect on the transcription of cytokines related to Th1 and Th2 responses. GT and MA, alone and in combination, were also assessed for their potential to alter metacaspase gene expression in L. major promastigotes by real-time RT-PCR. The hemolytic potential of GT and MA-treated promastigotes were also measured by routine UV absorbance reading. Electrophoresis on agarose gel was employed to analyze genomic DNA fragmentation.

RESULTS

GT demonstrated notable dose-dependent antileishmanial effects towards promastigotes and amastigotes of L. major. The IC₅₀ values for GT against L. major promastigotes and amastigotes were 46.76 mM and 25.89 mM, respectively. GT was considerably safer towards murine macrophages than L. major amastigotes with an SI value of 3.17. Transcriptional expression of iNOS, JAK-1, Interleukin (IL-10), and TGF-β was meaningfully decreased, while the levels of metacaspase mRNA were increased. Results also confirmed GT antioxidant activities. Also, increased levels of intracellular ROS were observed upon treatment of promastigotes with GT. The gel electrophoresis result indicated slight DNA fragmentation in the treated promastigotes by both drugs. A weak hemolytic effect was also observed for GT.

CONCLUSION

The results demonstrated that GT showed potent activity against L. major stages. It seems that its mechanism of action involves representing an immunomodulatory role towards upregulation of iNOS and JAK-1, while downregulation of IL-10 and TGF- β. Moreover, GT has an antioxidative potential and exerts its action through activating macrophages to kill the organism. Further in vivo and clinical studies are essential to explore its effect in future programs.

Curzerene antileishmania activity: Effects on Leishmania amazonensis and possible action mechanisms

Leishmaniasis is a set of infectious diseases with high rates of morbidity and mortality, it affects millions of people around the world. Treatment, mainly with pentavalent antimonials, presents significant toxicity and many cases of resistance. In previous works we have demonstrated the effective and selective antileishmanial activity of Eugenia uniflora L. essential oil, being constituted (47.3%) by the sesquiterpene curzerene. Considering the high rate of parasite inhibition demonstrated for E. uniflora essential oil, and the significant presence of curzerene in the oil, this study aimed to evaluate its antileishmania activity and possible mechanisms of action. Curzerene was effective in inhibiting the growth of promastigotes (IC₅₀ 3.09 ± 0.14 µM) and axenic amastigotes (EC₅₀ 2.56 ± 0.12 µM), with low cytotoxicity to RAW 264.7 macrophages (CC₅₀ 83.87 ± 4.63 µM). It was observed that curzerene has direct effects on the parasite, inducing cell death by apoptosis with secondary necrotic effects (producing pores in the plasma membrane). Curzerene proved to be even more effective against intra-macrophage amastigote forms, with an EC₅₀ of 0.46 ± 0.02 µM. The selectivity index demonstrated by curzerene on these parasite forms was 182.32, being respectively 44.15 and 8.47 times more selective than meglumine antimoniate and amphotericin B. The antiamastigote activity of curzerene was associated with immunomodulatory activity, as it increased TNF-α, IL-12, and NO levels, and lysosomal activity, and decreased IL-10 and IL-6 cytokine levels detected in macrophages infected and treated. In conclusion, our results demonstrate that curzerene is an effective and selective antileishmanial agent, a candidate for in vivo investigation in models of antileishmanial activity.

Biflavones from Platonia insignis Mart. Flowers Promote In Vitro Antileishmanial and Immunomodulatory Effects against Internalized Amastigote Forms of Leishmania amazonensis

Leishmaniasis is an infectious disease that affects millions of people worldwide, making the search essential for more accessible treatments. The species Platonia insignis Mart. (Clusiaceae) has been extensively studied and has gained prominence for its pharmacological potential. The objective of this work was to evaluate the antileishmania activity, cytotoxic effect and activation patterns of macrophages of hydroalcoholic extract (EHPi), ethyl acetate fractions (FAcOEt) and morelloflavone/volkensiflavone mixture (MB) from P. insignis flowers. EHPi, FAcOEt and MB demonstrated concentration-dependent antileishmania activity, with inhibition of parasite growth in all analyzed concentrations. EHPi exhibited maximum effect at 800 μg/mL, while FAcOEt and MB reduced the growth of the parasite by 94.62% at 800 μg/mL. EHPi, FAcOEt and MB showed low cytotoxic effects for macrophages at 81.78, 159.67 and 134.28 μg/mL, respectively. EHPi (11.25 µg/mL), FAcOEt (11.25 and 22.5 µg/mL) and MB (22.5 µg/mL) characterized the increase in lysosomal activity, suggesting a possible modulating effect. These findings open for the application of flowers from a P. insignis flowers and biflavones mixture thereof in the promising treatment of leishmaniasis.

Development of castor polyurethane scaffold (Ricinus communisL.) and its effect with stem cells for bone repair in an osteoporosis model

The development of 'smart' scaffolds has achieved notoriety among current prospects for bone repair, especially for chronic osteopathy, such as osteoporosis. Millions of individuals in the world suffer from poor bone healing due to osteoporosis. The objective of this work was to produce and characterize castor polyurethane (PU) scaffolds (Ricinus communisL.)andevaluate itsin vitrobiocompatibility with stem cells and osteoinductive effectin vivoon bone failures in a leporid model of osteoporosis. The material was characterized using Fourier-transform infrared spectroscopy, thermogravimetric analysis, SEM, and porosity analysis. Then, the biocompatibility was assessed by adhesion using SEM and cytotoxicity in a 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium assay. The osteoinductive effectin vivowas determined in bone defects in rabbit tibias (Oryctolagus cuniculus) submitted to castor PU scaffold, castor PU scaffold associated with stem cells, and negative control, after four and eight weeks, evaluated by computed microtomography and histopathology. The scaffolds were porous, with an average pore size of 209.5 ± 98.2 µm, absence of cytotoxicity, and positive cell adhesivenessin vitro.All the animals presented osteoporosis, characterized by multifocal osteoblastic inactivity and areas of mild fibrosis. There were no statistical differences between these treatments in the fourth week of treatment. In the eighth week, the treatment with castor PU scaffold alone induced more significant bone formation when compared to the other groups, followed by treatment with an association between castor PU scaffold and stem cells. The castor PU scaffold was harmless to cell culture, favoring cell adhesiveness and proliferation, in addition to inducing bone neoformation in osteoporotic rabbits.

Screening of six medicinal plant species for antileishmanial activity

This study is aimed to investigate the in vitro anti-leishmanial activity of ethanolic, aqueous or dichloromethane extracts of leaves, flowers, fruits or roots, of six medicinal plant species, namely, Nectandra megapotamica, Brunfelsia uniflora, Myrcianthes pungens, Anona muricata, Hymenaea stigonocarpa and Piper corcovandesis. After isolation and analysis of chemical components by ultra-high performance liquid chromatography-high-resolution tandem mass spectrometry (UHPLC-HRMS/MS), the extracts were also tested for toxicity in J774.A1 macrophages and human erythrocytes. Phenolic acids, flavonoids, acetogenins, alkaloids and lignans were identified in these extracts. Grow inhibition of promastigotes forms of Leishmania amazonensis and Leishmania braziliensis and the cytotoxicity in J774.A1 macrophages were estimated by the XTT method. The most promising results for L. amazonensis and L. braziliensis were shown by the ethanolic extract of the fruits of Hymenaea stigonocarpa and dichloromethane extract of the roots of Piper corcovadensis, with IC ₅₀ of 160 and 150 μg mL^-1, resp. Ethanolic extracts of A. muricata (leaf), B. uniflora (flower and leaf), M. pungens (fruit and leaf), N. megapotamica (leaf), and aqueous extract of H. stigonocarpa (fruit) showed IC ₅₀ > 170 μg mL^-1 for L. amazonensis and > 200 μg mL^-1 for L. braziliensis. The extracts exhibited low cytotoxicity towards J774.A1 macrophages with CC ₅₀ > 1000 μg mL^-1 and hemolytic activity from 0 to 46.1 %.

In vitro and in vivo toxicity and antibacterial efficacy of melittin against clinical extensively drug-resistant bacteria

BACKGROUND

Melittin is one of the most studied antimicrobial peptides, and several in vitro experiments have demonstrated its antibacterial efficacy. However, there is evidence showing melittin has non-promising effects such as cytotoxicity and hemolysis. Therefore, concerns about unwanted collateral toxicity of melittin lie ahead in the path toward its clinical development. With these considerations, the present study aimed to fill the gap between in vitro and in vivo studies.

METHODS

In the first step, in vitro toxicity profile of melittin was assessed using cytotoxicity and hemolysis tests. Next, a maximum intraperitoneal (i.p.) sub-lethal dose was determined using BALB/c mice. Besides toxicity, antimicrobial efficacy of melittin against extensively drug-resistant (XDR) Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus (MRSA), and KPC-producing Klebsiella pneumonia (KPC-KP) pathogens were tested using both in vitro and in vivo methods.

RESULTS

Melittin showed extensive hemolysis (HD50 = 0.44 µg/mL), and cytotoxicity (IC50 = 6.45 µg/mL) activities with i.p. LD50 value of 4.98 mg/kg in BALB/c mice. In vitro antimicrobial evaluation showed melittin MIC range from 8 to 32 µg/mL for the studied pathogens. Treatment of infected mice with repeated sub-lethal doses of melittin (2.4 mg/kg) displayed no beneficial effect on their survival and peritoneal bacterial loads.

CONCLUSIONS

These results indicate that melittin at its safe dose could not exhibit antimicrobial activity, which hinders its application in clinical practice.

Myrcene exerts anti-asthmatic activity in neonatal rats via modulating the matrix remodeling

Myrcene (MC), an organic hydrocarbon, was found to exert anti-inflammatory, analgesic, antimutagenic and antioxidant properties. However, the protective role of MC has not been reported against neonatal asthma. Wistar rats induced with asthma were administered with MC; while asthma control and vehicle control were maintained without MC administration. At the end of the experimental period, lung histology, inflammatory cell counts, cytokine analysis, matrix protein expressions were elucidated. Rats administered with MC exerted significant (P < 0.05) defense in protecting the lung tissue with the evidenced restoration of alveolar thickening of the lung tissues. Also, the present study elicited the anti-asthmatic activity of MC, especially via modulating the extracellular matrix protein expression in the asthma-induced animals, while a significant reduction (P < 0.05) in the fibrotic markers were found in MC treated animals. Moreover, the protective effect of MC was evidenced with reduced leukocyte infiltration in BALF, hypersensitive specific IgE levels with a profound decrease in the inflammatory cytokines such as IL-2, IL-4, IL-18, and IL-21 in MC administered animals compared to the asthma-induced group. To an extent, the markers of asthmatic inflammation such as CD14, MCP-1, and TARC were also found to be attenuated in MC exposed animals. The possible application of MC is a promising drug for the treatment of asthma-mediated complications.

β-Caryophyllene, A Natural Dietary CB2 Receptor Selective Cannabinoid can be a Candidate to Target the Trinity of Infection, Immunity, and Inflammation in COVID-19

Coronavirus disease (COVID-19), caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an ongoing pandemic and presents a public health emergency. It has affected millions of people and continues to affect more, despite tremendous social preventive measures. Identifying candidate drugs for the prevention and treatment of COVID-19 is crucial. The pathogenesis and the complications with advanced infection mainly involve an immune-inflammatory cascade. Therefore, therapeutic strategy relies on suppressing infectivity and inflammation, along with immune modulation. One of the most promising therapeutic targets for the modulation of immune-inflammatory responses is the endocannabinoid system, particularly the activation of cannabinoid type 2 receptors (CB2R), a G-protein coupled receptor which mediates the anti-inflammatory properties by modulating numerous signaling pathways. To pharmacologically activate the CB2 receptors, a naturally occurring cannabinoid ligand, beta-caryophyllene (BCP), received attention due to its potent anti-inflammatory, antiviral, and immunomodulatory properties. BCP is recognized as a full selective functional agonist on CB2 receptors and produces therapeutic effects by activating CB2 and the nuclear receptors, peroxisome proliferator-activated receptors (PPARs). BCP is regarded as the first dietary cannabinoid with abundant presence across cannabis and non-cannabis plants, including spices and other edible plants. BCP showed tissue protective properties and favorably modulates numerous signaling pathways and inhibits inflammatory mediators, including cytokines, chemokines, adhesion molecules, prostanoids, and eicosanoids. Based on its pharmacological properties, molecular mechanisms, and the therapeutic potential of BCP as an immunomodulator, anti-inflammatory, organ-protective, and antiviral, we hypothesize that BCP could be a promising therapeutic and/or preventive candidate to target the triad of infection, immunity, and inflammation in COVID-19. In line with numerous studies that proposed the potential of cannabinoids in COVID-19, BCP may be a novel candidate compound for pharmaceutical and nutraceutical development due to its unique functional receptor selectivity, wide availability and accessibility, dietary bioavailability, nonpsychoactivity, and negligible toxicity along with druggable properties, including favorable pharmacokinetic and physicochemical properties. Based on reasonable pharmacological mechanisms and therapeutic properties, we speculate that BCP has potential to be investigated against COVID-19 and will inspire further preclinical and clinical studies.

Eugenia piauhiensis Vellaff. essential oil and γ-elemene its major constituent exhibit antileishmanial activity, promoting cell membrane damage and in vitro immunomodulation

Leishmaniasis is considered as one of the most Neglected Tropical Diseases (NTDs) in the world, caused by protozoan parasites of the genus Leishmania. Treatment of leishmaniasis by chemotherapy remains a challenge because of limited efficacy, toxic side effects, and drug resistance. The search for new therapeutic agents from natural sources has been a constant for the treatment of diseases such as leishmaniasis. The objective of this study was to evaluate the biological activity of Eugenia piauhiensis Vellaff. essential oil (EpEO) and its major constituent γ-elemene on promastigote and amastigote forms of Leishmania (Leishmania) amazonensis, its cytotoxicity, and possible mechanisms of action. EpEO was more active (IC₅₀ 6.43 ± 0.18 μg/mL) against promastigotes than γ-elemene [9.82 ± 0.15 μg/mL (48.05 ± 0.73 μM)] and the reference drug miltefosine [IC₅₀ 17.25 ± 0.26 μg/mL (42.32 ± 0.64 μM)]. EpEO and γ-elemene exhibited low cytotoxicity against J774.A1 macrophages, with CC₅₀ 225.8 ± 3.57 μg/mL and 213.21 ± 3.3 μg/mL (1043 ± 16.15 μM), respectively. Additionally, EpEO and γ-elemene present direct activity against the parasite, decreasing plasma membrane integrity. EpEO and γ-elemene also proved to be even more active against intracellular amastigotes of the parasite [IC₅₀ 4.59 ± 0.07 μg/mL and 8.06 ± 0.12 μg/mL (39.44 ± 0.59 μM)], respectively), presenting indirect effects through macrophage activity modulation. Anti-amastigote activity was associated with increased TNF-α, IL-12, NO, and ROS levels. In conclusion, our results suggest EpEO and γ-elemene as promising candidates for new drug development against leishmaniasis.

Astronium fraxinifolium Schott Exerts Leishmanicidal Activity by Providing a Classically Polarized Profile in Infected Macrophages

BACKGROUND

Leishmania braziliensis is prevalent in Latin American countries, including Brazil. It causes cutaneous and mucocutaneous leishmaniasis, leading to high morbidity, and has a low cure rate. Treatment is based on pentavalent antimonials; nonetheless, there are problems related to high toxicity, high cost, and parasitic resistance. Discovery of new leishmanicidal drugs without these limitations and that stimulate the cellular immune response is necessary.

PURPOSE

The present work evaluates whether Astronium fraxinifolium Schott exerts leishmanicidal activity against L. braziliensis by providing a classically polarized profile in infected macrophages.

METHODS

For the evaluation of the A. fraxinifolium Schott leishmanicidal activity, amastigote cell death was demonstrated in infected RAW 267.4 macrophages treated with an ethanolic extract from the plant sapwood (EEAF). For the evaluation of the EEAF capacity in providing a classically polarized profile in infected macrophages, the following analyses were done: detection of LAMP-1 protein by the baculovirus technology, measurement of superoxide anion by the NBT testing, quantification of TNF-α, IL-12p40, IL-10, IL-4, and TGF-β by sandwich-type enzyme immune assays, and iNOS and COX-2 expression by RT-PCR technique.

RESULTS

The EEAF significantly reduced amastigote counts inside the cells. Vacuoles were visualized in infected and treated cells before and after May-Grünwald-Giemsa staining. A strong LAMP-1 protein fluorescence revealed phagosome maturation in infected cells treated with the EEAF. No production of superoxide was visualized in infected cells treated with the plant material. Nonetheless, high levels of TNF-α, IL-12p40, and IL-10 were found in cell supernatants, but reduced levels of TGF-β and no IL-4 production. We identified augmented mRNA expression for COX-2, but no expression of iNOS mRNA.

CONCLUSION

Our results demonstrated that A. fraxinifolium induced a classically polarized profile in infected macrophages but also provided a less harmful environment by stimulating the production of certain anti-inflammatory mediators, such as IL-10.

Effect of essential oils on Leishmania amazonensis: a systematic review

This systematic review investigated the evidence for the therapeutic potential of essential oils (EOs) against Leishmania amazonensis. We searched available scientific publications from 2005 to 2019 in the PubMed and Web of Science electronic databases, according to PRISMA statement. The search strategy utilized descriptors and free terms. The EOs effect of 35 species of plants identified in this systematic review study, 45.7% had half of the maximal inhibitory concentration (IC50) 10 < IC50 ⩽ 50 μg mL−1 and 14.3% had a 10 < IC50μg mL−1 for promastigote forms of L. amazonensis. EOs from Cymbopogon citratus species had the lowest IC50 (1.7 μg mL−1). Among the plant species analyzed for activity against intracellular amastigote forms of L. amazonensis, 39.4% had an IC50 10 < IC50 ⩽ 50 μg mL−1, and 33.3% had an IC50 10 < IC50μg mL−1. Aloysia gratissima EO showed the lowest IC50 (0.16 μg mL−1) for intracellular amastigotes. EOs of Chenopodium ambrosioides, Copaifera martii and Carapa guianensis, administered by the oral route, were effective in reducing parasitic load and lesion volume in L. amazonensis-infected BALB/c mice. EOs of Bixa orellana and C. ambrosioides were effective when administered intraperitoneally. Most of the studies analyzed in vitro and in vivo for the risk of bias showed moderate methodological quality. These results indicate a stimulus for the development of new phytotherapy drugs for leishmaniasis treatment.

In vitro and in vivo assessment of the antibacterial activity of colistin alone and in combination with other antibiotics against Acinetobacter baumannii and Escherichia coli

OBJECTIVES

Limited therapeutic options exist for treating severe infections caused by multidrug-resistant (MDR) and extensively drug-resistant Gram-negative bacteria (GNB). In this study, the activity of colistin (COL) as monotherapy and in combination with other antibiotics against Acinetobacter baumannii in vitro was investigated. In addition, the efficacy of intravenous colistimethate sodium (CMS) was evaluated in a murine model of urinary tract infection (UTI) induced by MDR Escherichia coli.

METHODS

Minimum inhibitory concentration (MIC), Monte Carlo simulation, fractional inhibitory concentration index (FICI), time-kill study and erythrocyte lysis assay were applied to evaluate the effect and cytotoxicity of COL, meropenem, imipenem, doripenem (DOR) and sulbactam alone and in combination. For the in vivo experiment, determination of the bacterial burden and histopathological examination were performed to evaluate the efficacy of CMS against UTI.

RESULTS

Of 106 A. baumannii isolates, 104 (98.1%) were susceptible to COL. In the chequerboard assay, COL + DOR showed the highest rate of synergism (60%). No antagonism or cytotoxicity was observed. All COL-based combinations were able to inhibit or slow bacterial re-growth in a time-kill assay. In an in vivo activity study, intravenous CMS reduced not only the bacterial load but also inflammation and maintained structural integrity of infected bladders and kidneys.

CONCLUSION

The effectiveness of COL alone in vitro and in vivo suggested that intravenous CMS will be an effective and available therapeutic strategy for UTI due to MDR-GNB. In-depth in vitro tests demonstrated that COL + DOR could be an attractive option, especially when the COL MIC is ≥1 μg/mL.

Development of Composite Scaffolds Based on Cerium Doped-Hydroxyapatite and Natural Gums-Biological and Mechanical Properties

Hydroxyapatite (HAp) is a ceramic material composing the inorganic portion of bones. Ionic substitutions enhance characteristics of HAp, for example, calcium ions (Ca²⁺) by cerium ions (Ce³⁺). The use of HAp is potentialized through biopolymers, cashew gum (CG), and gellan gum (GG), since CG/GG is structuring agents in the modeling of structured biocomposites, scaffolds. Ce-HApCG biocomposite was synthesized using a chemical precipitation method. The obtained material was frozen (–20 °C for 24 h), and then vacuum dried for 24 h. The Ce-HApCG was characterized by X-Ray diffractograms (XRD), X-ray photoemission spectra (XPS), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy (EDS). XRD and FTIR showed that Ce-HApCG was successfully synthesized. XRD showed characteristic peaks at 2θ = 25.87 and 32.05, corresponding to the crystalline planes (0 0 2) and (2 1 1), respectively, while phosphate bands were present at 1050 cm⁻¹ and 1098 cm⁻¹, indicating the success of composite synthesis. FESEM showed pores and incorporated nanostructured granules of Ce-HApCG. The mechanical test identified that Ce-HApCG has a compressive strength similar to the cancellous bone’s strength and some allografts used in surgical procedures. In vitro tests (MTT assay and hemolysis) showed that scaffold was non-toxic and exhibited low hemolytic activity. Thus, the Ce-HApCG has potential for application in bone tissue engineering.

An extract from Myracrodruon urundeuva inhibits matrix mineralization in human osteoblasts

ETHNOPHARMACOLOGICAL RELEVANCE

Phytotherapy based on plant-derived compounds is an alternative medicinal strategy for the relief of symptoms and the curing of diseases. The leaves of Myracrodruon urundeuva a medicinal plant also known as "aroeira", has been used in traditional medicine as healing, antiulcer and anti-inflammatory to treat skeletal diseases in Brazil, but its role in bone cell toxicity, as well as in bone formation, remains to be established.

AIM OF THE STUDY

We sought to determine the in vitro osteogenic effects of a hydroalcoholic M. urundeuva leaves extract in primary human osteoblasts.

MATERIALS AND METHODS

Cell viability, reactive oxygen species (ROS) production, alkaline phosphatase (ALP) activity and matrix mineralization were evaluated by MTT assay, DCFH-DA probe, colorimetric-based enzymatic assay and Alizarin Red-staining, respectively. Besides, the matrix metalloproteinase (MMP)-2 and progressive ankylosis protein homolog (ANKH) gene expression were determined by real-time RT-qPCR and MMP-2 activity by zymography.

RESULTS

Exposure of osteoblasts to M. urundeuva extract significantly decreased viability and increased reactive oxygen species (ROS) production, regardless of the extract concentration. The M. urundeuva extract at 10 μg/mL also downregulated matrix metalloproteinase (MMP)-2, while upregulating progressive ankylosis protein homolog (ANKH) gene expression. By contrast, the MMP-2 activity was unchanged. The M. urundeuva extract at 10 μg/mL also reduced alkaline phosphatase (ALP) activity and mineralization.

CONCLUSIONS

Overall, our findings suggest that the inhibition of osteogenic differentiation and matrix mineralization promoted by M. urundeuva may be due more to an increase in oxidative stress than to the modulation of MMP-2 and ANKH expression.

Gastroprotective and anti-inflammatory activities integrated to chemical composition of Myracrodruon urundeuva Allemão - A conservationist proposal for the species

ETHNOPHARMACOLOGICAL RELEVANCE

Myracrodruon urundeuva Allemão (Aroeira-do-Sertão), Anacardiaceae, is one of the most used plants in folk medicine in Northeastern Brazil as an anti-inflammatory, healing and antiulcer. This species is threatened with extinction due to anthropogenic exploitation. The importance of this study is to demonstrate the feasibility of a conservationist model of replacement of the M. urundeuva adult tree (inner bark) for its under developing plants (shoots) in order to ensure the preservation of this species, but also to ensure sufficient raw material for pharmaceutical purposes.

AIM OF THE STUDY

To characterize chemically and assess the gastroprotective and anti-inflammatory activities of the fluid extracts from M. urundeuva innebark (adult plant) as well as stem and leaves of shoots (young plant).

MATERIALS AND METHODS

The fluid extracts were prepared by maceration-percolation with hydroalcoholic solution according to the methodology described in the Brazilian Pharmacopoeia. These extracts were cleaned-up through solid phase extraction (SPE) and chemically characterized by ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-ESI-QTOF MS/MS). Gastroprotective and anti-inflammatory activities of the extracts (700 or 1000 mg/kg) were assessed on ethanol-induced gastric lesions and Croton oil-induced ear edema in rats, respectively. The extracts were evaluated for cytotoxicity in vitro.

RESULTS

The UPLC-ESI-QTOF-MS/MS analysis evidenced the presence of chalcones, flavonoids and tannins. Gastroprotective and anti-inflammatory activities achieved with fluid extracts from the stems and leaves was similar to inner bark. The fluid extracts were not toxic.

CONCLUSION

It is possible to replace the inner bark of the adult tree for the stems and leaves from the shoots as raw material to be used in the preparation of its the phytotherapeutics. Therefore, this finding may help in the implementation of public policies that ensure the conservation of the species along with its sustainable use for pharmaceutical purposes.

Myracrodruon urundeuva seed exudates proteome and anthelmintic activity against Haemonchus contortus

Seed exudates are plant-derived natural bioactive compounds consisting of a complex mixture of organic and inorganic molecules. Plant seed exudates have been poorly studied against parasite nematodes. This study was undertaken to identify proteins in the Myracrodruon urundeuva seed exudates and to assess the anthelmintic activity against Haemonchus contortus, an important parasite of small ruminants. M. urundeuva seed exudates (SEX) was obtained after immersion of seeds in sodium acetate buffer. SEX was fractionated with ammonium sulfate at 0–90% concentration to generate the ressuspended pellet (SEXF1) and the supernatant (SEXF2). SEX, SEXF1, and SEXF2 were exhaustively dialyzed against distilled water (cut-off: 12 kDa) and the protein contents determined. Mass spectrometry analyses of SEX, SEXF1, and SEXF2 were done to identify proteins and secondary metabolites. The seed exudates contained protease, protease inhibitor, peptidase, chitinase, and lipases as well as the low molecular weight secondary compounds ellagic acid and quercetin rhamnoside. SEX inhibited H. contortus larval development (LDA) (IC₅₀ = 0.29 mg mL^-1), but did not affect larval exsheathment (LEIA). On the other hand, although SEXF1 and SEXF2 inhibited H. contortus LEIA (IC₅₀ = 1.04 and 0.93 mg mL^-1, respectively), they showed even greater inhibition efficiency of H. contortus larval development (IC₅₀ = 0.29 and 0.42 mg mL^-1, respectively). To the best of our knowledge, this study is the first to show the anthelmintic activity of plant exudates against a gastrointestinal nematode. Moreover, it suggests the potential of exuded proteins as candidates to negatively interfere with H. contortus life cycle.

Analysis of the Variability of Therapeutic Indications of Medicinal Species in the Northeast of Brazil: Comparative Study

ETHNOPHARMACOLOGICAL RELEVANCE

This study aims to evaluate the versatility of these species and their agreement of use and/or the informants' knowledge and verify the variability of the information on the indicated medicinal species in comparison to other species from northeastern Brazilian areas.

MATERIALS AND METHODS

Ethnobotanical information was acquired through interviews with 23 residents of the Quincuncá community, northeastern Brazil. From the obtained data, a comparative analysis of the therapeutic indications with other 40 areas in different biomes was conducted. For that, the relative importance index and informant consensus factor were calculated and compared to other indices evaluated in the literature.

RESULTS

A total of 39 medicinal species were cited and twenty-six species showed similarities among their therapeutic indications; however, species as Geoffroea spinosa, Lantana camara, and others can be highlighted, present in community disease indications that were not verified for other areas. Myracrodruon urundeuva, Mimosa tenuiflora, Stryphnodendron rotundifolium, and Amburana cearensis had the greatest versatility. In the Quincuncá community, medicinal species were indicated for 49 diseases, which were grouped into 15 categories of body systems.

CONCLUSION

This study shows the presented divergence in relation to their therapeutic use; in this point, these divergences reinforce the importance of pharmacological research.

Chemical composition and evaluation of the antibacterial and Cytotoxic activities of the essential oil from the leaves of Myracrodruon urundeuva

BACKGROUND

This study evaluated the in vitro activity of essential oil extracted from the leaves of Myracrodruon urundeuva.

METHODS

The oil was obtained by hydro-distillation and characterized by Gas Chromatography coupled to Mass Spectrometry (GC-MS) and Gas Chromatography with Flame Ionization Detector (GC-FID). The antibacterial activity was evaluated by the broth microdilution technique and the MIF was determined by using growth indicator CTT (2,3,5-triphenyl-tetrazolium) and CBM in BHI agar. The oil's cytotoxicity was evaluated in HeLa, HEK-293, and Vero E6 cells using MTT, 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyl tetrazolium.

RESULTS

The oil showed chemical markers, including α-pinene (87.85%), trans-caryophyllene (1.57%), limonene (1.49%) and β -pinene (1.42%), and activity against all strains: Staphylococcus aureus (MIC = MBC = 0.22 mg/mL), Staphylococcus epidermidis (MIC = 0.11 mg/mL and MBC = 0.22 mg/mL), Escherichia coli (MIC = 0.88 mg/mL and MBC = 1.75 mg/mL), Pseudomonas aeruginosa (MIC = MBC = 7 mg/mL) and Salmonella Enteritidis (MIC = MBC = 0.44 mg/mL). In vitro cytotoxicity tests showed that the oil is not toxic and has slight antitumor activity.

CONCLUSIONS

We conclude that the M. urundeuva oil results are promising, with prospects of being pharmacologically viable.