Aqueous extract of Swietenia macrophylla leaf exerts an anti-inflammatory effect in a murine model of Parkinson's disease induced by 6-OHDA.

Introduction: Parkinson's disease affects 2% of the population aged over 65 years and is the second most common neurodegenerative disorder in the general population. The appearance of motor symptoms is associated with the degeneration of dopaminergic neurons in the nigrostriatal pathway. Clinically significant nonmotor symptoms are also important for severe disability with disease progression. Pharmacological treatment with levodopa, which involves dopamine restitution, results in a temporary improvement in motor symptoms. Among the mechanisms underlying the pathogenesis of the disease are exacerbated oxidative stress, mitochondrial dysfunction, and neuroinflammation. A phytochemical prospecting study showed that the aqueous extract of the leaves from Swietenia macrophylla (Melineaceae), known as mahogany, has polyphenols with antioxidant and anti-inflammatory capacity in a significantly higher percentage than leaf extracts from other Amazonian plants. Furthermore, the antioxidant and anti-inflammatory capacity of aqueous extract of mahogany leaf has already been demonstrated in an in vitro model. In this study, we hypothesized that the aqueous extract of mahogany leaf (AEML) has a neuroprotective effect in a murine model of Parkinson's disease induced by 6-hydroxidopamine (6-OHDA), due to antioxidant and anti-inflammatory properties of its phenolic compounds. Methods: Mice were treated daily with the mahogany extract at a dose of 50 mg/kg, starting 7 days before 6-OHDA infusion until post-surgery day 7. Results and discussion: The animals from the 6-OHDA/mahogany group, which corresponds to animals injected with the toxin and treated with aqueous extract of the mahogany leaf, presented distinct behavioral phenotypes after apomorphine challenge and were therefore subdivided into 2 groups, 6-OHDA/mahogany F1 and 6-OHDA/mahogany F2. The F1 group showed a significant increase in contralateral rotations, whereas the F2 group did not show rotations after the apomorphine stimulus. In the F1 group, there was an increase, although not significant, in motor performance in the open field and elevated plus maze tests, whereas in the F2 group, there was significant improvement, which may be related to the lesser degree of injury to the nigrostriatal dopaminergic pathway. The TH+ histopathological analysis, a dopaminergic neuron marker, confirmed that the lesion to the nigrostriatal dopaminergic pathway was more pronounced in 6-OHDA/mahogany F1 than in 6-OHDA/mahogany F2. Our main result consisted of signs of improvement in the inflammatory profile in both the F1 and F2 6-OHDA/mahogany groups, such as a lower number of IBA-1+ microglial cells in the ventral striatum and substantia nigra pars compacta and a reduction in GFAP+ expression, an astrocyte marker, in the dorsal striatum. In this study, several bioactive compounds in the aqueous extract of mahogany leaf may have contributed to the observed beneficial effects. Further studies are necessary to better characterize their applicability for treating chronic degenerative diseases with inflammatory and oxidative bases, such as Parkinson's disease.

Exploring the antiviral potential of justicidin B and four glycosylated lignans from Phyllanthus brasiliensis against Zika virus: A promising pharmacological approach.

BACKGROUND: Zika virus (ZIKV) is an emerging arbovirus that in recent years has been associated with cases of severe neurological disorders, such as microcephaly in newborns and Guillain-Barré syndrome in adults. As there is no vaccine or treatment, the search for new therapeutic targets is of great relevance. In this sense, plants are extremely rich sources for the discovery of new bioactive compounds and the species Phyllanthus brasiliensis (native to the Amazon region) remains unexplored. PURPOSE: To investigate the potential antiviral activity of compounds isolated from P. brasiliensis leaves against ZIKV infection. METHODS: In vitro antiviral assays were performed with justicidin B (a lignan) and four glycosylated lignans (tuberculatin, phyllanthostatin A, 5-O-ß-d-glucopyranosyljusticidin B, and cleistanthin B) against ZIKV in Vero cells. MTT colorimetric assay was used to assess cell viability and plaque forming unit assay to quantify viral load. In addition, for justicidin B, tests were performed to investigate the mechanism of action (virucidal, adsorption, internalization, post-infection). RESULTS: The isolated compounds showed potent anti-ZIKV activities and high selectivity indexes. Moreover, justicidin B, tuberculatin, and phyllanthostatin A completely reduced the viral load in at least one of the concentrations evaluated. Among them, justicidin B stood out as the main active, and further investigation revealed that justicidin B exerts its antiviral effect during post-infection stages, resulting in a remarkable 99.9 % reduction in viral load when treatment was initiated 24 h after infection. CONCLUSION: Our findings suggest that justicidin B inhibits endosomal internalization and acidification, effectively interrupting the viral multiplication cycle. Therefore, the findings shed light on the promising potential of isolated compounds isolated from P. brasiliensis, especially justicidin B, which could contribute to the drug development and treatments for Zika virus infections.

Putative Identification of New Phragmaline-Type Limonoids from the Leaves of Swietenia macrophylla King: A Case Study Using Mass Spectrometry-Based Molecular Networking.

Swietenia macrophylla King is a plant commonly known as Brazilian mahogany. The wood from its stem is highly prized for its exceptional quality, while its leaves are valued for their high content of phragmalin-type limonoids, a subclass of compounds known for their significant biological activities, including antimalarial, antitumor, antiviral, and anti-inflammatory properties. In this context, twelve isolated limonoids from S. macrophylla leaves were employed as standards in mass spectrometry-based molecular networking to unveil new potential mass spectrometry signatures for phragmalin-type limonoids. Consequently, ultra-performance liquid chromatography coupled with high-resolution mass spectrometry was utilized for data acquisition. Subsequently, the obtained data were analyzed using the Global Natural Products Social Molecular Networking platform based on spectral similarity. In summary, this study identified 24 new putative phragmalin-type limonoids for the first time in S. macrophylla. These compounds may prove valuable in guiding future drug development efforts, leveraging the already established biological activities associated with limonoids.

Margaritaria nobilis L.f. (Phyllanthaceae) Ethanolic Extract: Low Acute Oral Toxicity and Antinociceptive Activity.

Margaritaria nobilis L.f. (Phyllanthaceae), a native Brazilian tree occurring mainly in the Amazon, is used in folk medicine for the treatment of abscesses (bark) and cancer-like symptoms (leaves). The present study evaluates the safety of its acute oral administration and its effects on nociception and plasma leakage. The chemical constitution of the leaf's ethanolic extract is determined by ultra-performance liquid chromatography-high-resolution mass spectrometry (LC-MS. Its acute oral toxicity is evaluated in female rats at a dose of 2000 mg/kg, evaluating the occurrence of deaths and Hippocratic, behavioral, hematological, biochemical, and histopathological changes, as well as food and water consumption and weight gain. Antinociceptive activity is evaluated in male mice with acetic-acid-induced peritonitis (APT) and formalin (FT) tests. An open field (OF) test is performed to verify possible interferences in the animals' consciousness or locomotion. LC-MS analysis shows the presence of 44 compounds classified as phenolic acid derivatives, flavonoids and O-glycosylated derivatives, and hydrolyzable tannins. No deaths or significant behavioral, histological, or biochemical changes are observed in the toxicity assessment. In nociception tests, M. nobilis extract significantly reduces abdominal contortions in APT, demonstrating selectivity for inflammatory components (FT second phase), not interfering in neuropathic components (FT first phase) or consciousness and locomotion levels in OF. Additionally, M. nobilis extract inhibits plasma acetic-acid-induced leakage. These data demonstrate the low toxicity of M. nobilis ethanolic extract, as well as its effectiveness in modulating inflammatory nociception and plasma leakage, possibly related to the flavonoids and tannins present in its composition.

Antibacterial Activity from Momordica charantia L. Leaves and Flavones Enriched Phase.

Momordica charantia L. (Cucurbitaceae) is a plant known in Brazil as "melão de São Caetano", which has been related to many therapeutic applications in folk medicine. Herein, we describe antibacterial activities and related metabolites for an extract and fractions obtained from the leaves of that species. An ethanolic extract and its three fractions were used to perform in vitro antibacterial assays. In addition, liquid chromatography coupled to mass spectrometry and the molecular networking approach were used for the metabolite annotation process. Overall, 25 compounds were annotated in the ethanolic extract from M. charantia leaves, including flavones, terpenes, organic acids, and inositol pyrophosphate derivatives. The ethanolic extract exhibited low activity against Proteus mirabilis (MIC 312.5 µg·mL-1) and Klebsiella pneumoniae (MIC 625 µg·mL-1). The ethyl acetate phase showed interesting antibacterial activity (MIC 156.2 µg·mL-1) against Klebsiella pneumoniae, and it was well justified by the high content of glycosylated flavones. Therefore, based on the ethyl acetate phase antibacterial result, we suggest that M. charantia leaves could be considered as an alternative antibacterial source against K. pneumoniae and can serve as a pillar for future studies as well as pharmacological application against the bacteria.

Margaritaria nobilis L.F. (Phyllanthaceae): Ethnopharmacology and Application of Computational Tools in the Annotation of Bioactive Molecules.

Margaritaria nobilis is a shrubby species widely distributed in Brazil from the Amazon to the Atlantic Rainforest. Its bark and fruit are used in the Peruvian Amazon for disinfecting abscesses and as a tonic in pregnancy, respectively, and its leaves are used to treat cancer symptoms. From analyses via UHPLC-MS/MS, we sought to determine the chemical profile of the ethanolic extract of M. nobilis leaves by means of putative analyses supported by computational tools and spectral libraries. Thus, it was possible to annotate 44 compounds, of which 12 are phenolic acid derivatives, 16 are O-glycosylated flavonoids and 16 hydrolysable tannins. Among the flavonoids, although they are known, except for kaempferol, which has already been isolated from this species, the other flavonoids (10, 14, 15, 21, 24-26, 28-30, 33-35, 40 and 41) are being reported for the first time in the genus. Among the hydrolysable tannins, six ellagitannins present the HHDP group (6, 19, 22, 31, 38 and 43), one presents the DHHDP group (5), and four contain oxidatively modified congeners (12, 20, 37 and 39). Through the annotation of these compounds, we hope to contribute to the improved chemosystematics knowledge of the genus. Furthermore, supported by a metric review of the literature, we observed that many of the compounds reported here are congeners of authentically bioactive compounds. Thus, we believe that this work may help in understanding future pharmacological activities.

Obtainment of the spray-dried extracts of Peperomia pellucida L. (H.B.K.) using different atomization temperatures: physicochemical characterization and technological development for pharmaceutical applications.

Spray-dried extracts are prepared as powders or granules after solvent removal, which can be obtained in the presence or absence of pharmaceutical adjuvants. This work aimed to optimize the process of obtaining dried extracts of Peperomia pellucida L. (HBK) by spray drying. The characterization of the extract was performed by thermal analysis, specific surface area, particle size and high performance liquid chromatography (HPLC); then, capsules were developed for antimicrobial treatment, evaluating four bench lots by the determination of the angle of repose and time of flow, scanning electron microscopy, porosity and physicochemical quality control. There were no significant differences between the extracts obtained by spray drying at atomization temperatures of 140 °C, 160 °C and 180 °C, which was confirmed by thermal analysis. Specific surface area varied inversely with the mean particle size. Regarding the marker content by HPLC, no significant differences were found between the samples, although the flavonoid fraction was more stable at 160 °C. Bench lots (I to IV) were developed using the diluents Flowlac®, Starch® 1500, microcrystalline cellulose 250 and Cellactose® 80. Based on the results, the bench lot I, containing Flowlac®, was selected. The results of physicochemical quality control demonstrated that the selected formulation meets the pre-established parameters, and proving to be economically viable.

Leishmanicidal activity of Piper marginatum Jacq. from Santarém-PA against Leishmania amazonensis.

Leishmaniasis is an infectious disease that has high endemicity and is among the six parasitic diseases of higher occurrence in the world. The current treatments are limited due to their toxicity, treatment resistance and high cost which have increased the search for new substances of natural origin for its therapy. Based on this, an in vitro biological and chemical investigation was carried out to evaluate the potential of Piper marginatum against Leishmania amazonesis. P. marginatum leaves were collected to obtain the essential oil (EO) and the ethanolic extract (CE). The chemical profile of the CE and fractions was obtained by 1H NMR. The analysis of the EO chemical composition was performed by GC-MS. EO, CE and fractions were submitted to antileishmanial and cytotoxicity assays against macrophages. The chromatographic profiles of EO, CE and fractions showed the presence of phenolic compounds and terpenoids, having 3,4-Methylenedioxypropiophenone as a major compound. All P. marginatum samples showed low toxicity to macrophages. The CE and the methanolic, hexane and ethyl acetate fractions had low cytotoxicity when compared to Pentamidine. All tested samples inhibited growth of L. amazonensis promastigotes. The antileishmanial activity of EO, CE and fractions were evaluated in macrophages infected with L. (L.) amazonensis and treated with the concentrations 1, 10 and 100 µg/mL for 48 h. All samples were active, but EO and CE showed superior activity against amastigote forms when compared to the promastigote forms of L. amazonensis. This work describes for the first time the antileishmanial activity of the species P. marginatum and its cytotoxicity against macrophages, suggesting that it can be an alternative source of natural products in the phytotherapeutic treatment of leishmaniasis.

Chemical profiling of Curatella americana Linn leaves by UPLC-HRMS and its wound healing activity in mice.

Based on ethnopharmacological studies, a lot of plants, as well as its compounds, have been investigated for the potential use as wound healing agents. In Brazil, Curatella americana is traditionally used by local people to treat wounds, ulcers and inflammations. However, to the best of our knowledge, its traditional use in the treatment of wounds has not been validated by a scientific study. Here, some compounds, many of them flavonoids, were identified in the hydroethanolic extract from the leaves of C. americana (HECA) by LC-HRMS and LC-MS/MS. Besides that, solutions containing different concentrations of HECA and a gel produced with this extract were evaluated for its antimicrobial, coagulant and wound healing activities on an excision mouse wound model as well as its acute dermal safety. A total of thirteen compounds were identified in HECA, mainly quercetin, kaempferol and glucoside derivatives of both, besides catechin and epicatechin known as wound healing agents. The group treated with 1% of HECA exhibited highest wound healing activity and best rate of wound contraction confirmed by histopathology results. The present study provides scientific evidence of, this extract (HECA) possess remarkable wound healing activity, thereby, supporting the traditional use.

Chemical Composition, Toxicity, Antinociceptive, and Anti-Inflammatory Activity of Dry Aqueous Extract of Varronia multispicata (Cham.) Borhidi (Cordiaceae) Leaves.

Varronia multispicata (Cham.) Borhidi (Cordiaceae), an herbaceous plant distributed in tropical and subtropical regions is native of Brazil and widely used in folk medicine to treat respiratory and digestive diseases, inflammation, and some types of infections. Thus, this study aimed to investigate acute oral toxicity, antinociceptive, and anti-inflammatory activities of dry aqueous extract of V. multispicata (AEVm) and to identify its compounds. Extract was obtained by lyophilized leaf infusion and its composition was analyzed by ultra-performance liquid chromatography-high resolution mass spectrometry (LC-MS). Acute oral toxicity was evaluated in female rats treated with AEVm (2,000 mg/kg) in a single oral dose. Mortality, body weight changes, feed and water intake, organ weights, histological and biochemical parameters were screened for 14 days. Antinociceptive activity was evaluated by writhing (WT), formalin (FT), and hot plate (HP) tests in male mice while anti-inflammatory activity was performed by carrageenan (CPE) and dextran (DPE)-induced paw edema tests and carrageenan-induced peritonitis (CP) test in male rats. Additionally, spontaneous open-field (OF) locomotion was evaluated. LC-MS analysis revealed the presence of flavonoids with biological activity. In toxicity evaluation, extract did not cause deaths in dose of 2,000 mg/kg, and there were no significant behavioral or biochemical alterations. Additionally, evidence of hepatoprotective and antioxidant activity was observed. In pharmacological evaluation AEVm showed dose-dependent antinociceptive activity in WT, with a median effective dose of 146.89 mg/kg, which showed selectivity by inflammatory base processes (FT first phase; p < 0.001), showing no activity in neuropathic nociception components (FT second phase and HP) or about consciousness and locomotion in OF. AEVm also showed significant anti-inflammatory activity, inhibiting CPE (p < 0.001) and cell migration (p < 0.05) and nitric oxide (NO) production (p < 0,01) in CP test. These data demonstrate that AEVm has low oral toxicity-with evidence of hepatoprotective and antioxidant properties-antinociceptive and anti-inflammatory activity, supporting V. multispicata traditional use, possibly related to flavonoids present in its constitution.

Plants used to treat snakebites in Santarém, western Pará, Brazil: an assessment of their effectiveness in inhibiting hemorrhagic activity induced by Bothrops jararaca venom.

ETHNOPHARMACOLOGICAL RELEVANCE: The poor distribution and limited availability of antivenoms in Brazil have led to greater use of plants to treat snakebites. Very often such plants are the only alternative available to riverside communities. MATERIALS AND METHODS: Direct questionnaire-based interviews were conducted with members of the Cucurunã, São Pedro and Alter do Chão communities in Santarém, Pará, Brazil. For each of the 12 most frequently mentioned species aqueous extracts were prepared and the phytochemical profiles determined by thin layer chromatography. The concentrations of phenolic compounds (tannins and flavonoids) in the aqueous extracts were determined by colorimetric assays. To assess inhibition of the hemorrhagic activity of Bothrops jararaca venom, solutions containing the venom mixed with aqueous extracts in the ratios 1:12 and 1:48 were tested (w/w). SDS-PAGE and Western blot were used to assess the action of the extracts on Bothrops jararaca venom. RESULTS: In all, 24 plants belonging to 19 families were mentioned in the survey as being used to treat snakebites. Leaves (84%), seeds (60.9%) and inner bark (53%) were cited as the most frequently used parts in folk remedies, which were usually prepared in the form of a decoction (62.5%), tincture (45%) or maceration (22.5%). Hemorrhage induced by Bothrops jararaca venom was completely inhibited by aqueous extracts of Bellucia dichotoma, Connarus favosus, Plathymenia reticulata and Philodendron megalophyllum, which had a high phenolic content and contained condensed and hydrolyzable tannins. The results of SDS-PAGE showed that some venom protein bands were not visible when the venom was preincubated with the extracts that had completely inhibited hemorrhagic activity of the venom. Western blot showed that the extracts did not have any enzymatic action on the proteins in the venom as it failed to detect low-molecular-weight bands, which are indicative of possible enzymatic cleavage. CONCLUSIONS: Traditional use of plants to treat snakebites is a common practice in the western region of Pará, Brazil. Our findings show that some plant extracts were able to inhibit snake venom-induced hemorrhage in vitro. In vivo studies are being carried out to validate the traditional use of these species to treat snakebites.

Antiplasmodial activity of the andiroba (Carapa guianensis Aubl., Meliaceae) oil and its limonoid-rich fraction.

ETHNOPHARMACOLOGICAL RELEVANCE: From seeds of Carapa guianensis the Amazon native people extracts the andiroba oil, which is traditionally used as febrifuge, anti-malarial, insecticidal and repellant. The non-saponifiable fraction separated from the oil is rich in limonoids, which assigns its pharmacological effects. MATERIALS AND METHODS: The andiroba oil and its limonoid-rich fraction were submitted to in vitro antiplasmodial bioassay using W(2) and Dd(2) strains of Plasmodium falciparum. The acute toxicity of andiroba oil was evaluated. The limonoid-rich fraction was subjected to fractionation and identified its major constituents. RESULTS: Andiroba oil and its limonoid-rich fraction inhibited the growth of W(2) clone in 100%, between 24 and 72 h, at concentrations of 8.2 µg/mL and 3.1 µg/mL, respectively. Under the same conditions, the parasitaemia of Dd(2) clone provoked by the andiroba oil showed inhibition of 31% (IC(50) >82 µg/mL) with a time-dependent relationship of 24h and inhibition of 88% (IC(50) 8.4 µg/mL) after 72 h, while for the limonoid-rich fraction the inhibition of Dd(2) clone was 56% (IC(50) 2.8µg/mL) at 24h and 82% (IC(50) 0.4 µg/mL) after 72 h. Andiroba oil in acute toxicity test with a fixed dose (LD(50) >2000 mg/kg) was not toxic The limonoids identified in the oil were gedunin, 6α-acetoxygedunin, 7-deacetoxy-7-oxogedunin, 7-deacetylgedunin, 1,2-dihydro-3ß-hydroxy-7-deacetoxy-7-oxogedunin and andirobin. Gedunin and derivatives has been reputed as anti-malarials. CONCLUSION: The results support the traditional use of andiroba oil as antiplasmodial, which additionally proved not to be toxic in bioassays conducted with mice.

Limonoids of the phragmalin type from Swietenia macrophylla and their chemotaxonomic significance.

Species of Swietenia elaborate limonoid chemistry along only one route, which leads to the mexicanolide type in most species and the phragmalin type in S. mahogani. A hexane extract from leaves of S. macrophylla afforded six new phragmalins with a 8,9,30-ortho-ester unit, namely, 6-O-acetylswietephragmin E (1), 3beta-O-destigloyl-3beta-O-benzoyl-6-O-acetylswietephragmin E (2), 12alpha-acetoxyswietephragmin C (3), 3beta-O-destigloyl-3beta-O-benzoyl-12alpha-acetoxyswietephragmin C (4), 12alpha-acetoxyswietephragmin D (5), and 3beta-O-destigloyl-3beta-O-benzoyl-12alpha-acetoxyswietephragmin D (6). This appears to be the first record of phragamalins from S. macrophylla, and this study shows the potential of tricyclic [3.3.1(2,10).1(1,4)]-decane limonoids as taxonomically useful chemical markers in the Meliaceae.