Plants used in the treatment of leishmanial ulcers due to Leishmania (Viannia) braziliensis in an endemic area of Bahia, Brazil

Comprehensive phytochemical and toxicological analysis of Chenopodium ambrosioides (L.) fractions

Chenopodium ambrosioides aerial parts have been historically employed in traditional medicine for addressing various ailments such as headaches, abdominal discomfort, joint issues, and respiratory disorders, alongside treatments for lice and warts. This study aimed to conduct a comprehensive phytochemical analysis of C. ambrosioides and assess the acute and subacute toxicity of oral treatments using fractions in preclinical trials. Spectrophotometric analysis via LC-MS/MS was used to characterize the plant's chemical composition. Acute toxicity evaluation followed Organisation for Economic Co-operation and Development code 42 guidelines, conducted on adult male and female Wistar strain mice. Subsequently, Swiss mice were divided into six groups for the subacute toxicity study, receiving oral doses of 200 mg/kg extracts and fractions for 28 days. Daily observations and biochemical analyses were performed, with LC-MS/MS revealing a diverse array of compounds including organic acids, flavonoids, phenolic acids, rutin, hesperidin, nicotiflorine, and fumaric acid. Results indicated no lethality or alterations in body weight in treated groups, though some organ weight changes were noted. Biochemical analyses demonstrated values within the normal range for all groups, suggesting that the treatments did not induce adverse effects. Acute and subacute treatments with fractions did not result in lethality or toxic alterations at therapeutic doses, implying the safety of the product at appropriate levels. This study underscores the potential of C. ambrosioides as a safe therapeutic option warranting further exploration.

The Meaning of Plants' Names: A New Discovering Approach to Its Medicinal and/or Toxic Properties

Some of the vernacular or scientific names are related to possible medicinal and/or toxic properties that can reveal the presence of potential bioactive agents, contributing to the discovery of new drugs and/or knowledge of the risks associated with their use. This study sought to list the scientific and vernacular names of plants whose lexicons are related to those possible properties of plants and to compare them with the "ethno" (ethnobotanical and ethnopharmacological) and pharmacological data available in the scientific literature. A floating reading of the two classical and reference works on Brazilian medicinal plants was performed, and plants with vernacular and/or scientific names related to the possible medicinal and/or toxic properties were listed. Correlations between the meanings of the species' names (lexicon) and their possible biological properties were made from their translation from Latin by consulting dictionaries. A bibliographic survey was conducted on the "ethno" and pharmacological data for each species. Finally, data from these three dimensions (lexicon, "ethno," and pharmacology) were classified and compared using a bioprospection classification. It resulted in a list of 90 plant species belonging to 47 families. 66 of the 90 species presented "ethno" data from the scientific literature, while 46 species presented pharmacological data. Of these, 46 (69.7%) and 27 (58.7%), respectively, showed equivalence with the possible medicinal and/or toxic properties of plants according to their lexicons. According to this study, half of the plants investigated demonstrate equivalence in the three dimensions analyzed (lexicons, "ethno," and pharmacological data from the scientific literature). Gastrointestinal and nervous system categories are among the most common in all three dimensions. Plant lexicons may be closely linked to the possible medicinal and/or toxic properties and the study of plant lexicons may represent one more approach for the search for new drugs, mainly considering the gastrointestinal, nervous, and parasites categories.

Female naturalists and the patterns of suppression of women scientists in history: the example of Maria Sibylla Merian and her contributions about useful plants

BACKGROUND

This work reunites many women naturalists who registered knowledge about native flora in scientific expeditions around the globe between the seventeenth and nineteenth centuries. Since male naturalists are more recognized in this period of time, we aimed to list female naturalists that published plant descriptions and observations, focusing on the work of Maria Sibylla Merian and to analyze her trajectory as an example to discuss the patterns of the suppression of women scientists. A second aim was to inventory the useful plants described in Maria Sibylla's Metamorphosis Insectorum Surinamensium and find pharmacological evidence about the traditional uses described for those plants cited as medicinal and toxic.

METHODS

A survey of female naturalists was carried out by searching information in Pubmed, Scielo, Google Scholar and Virtual Health Library. Once Maria Sibylla published her book Metamorphosis Insectorum Surinamensium by her own, without male co-authors, and also this book is one of the only to have text and illustrations altogether and there are reports indicating information on useful plants in this work, she and her book were chosen as subject of this research. All the information was tabulated by dividing the plants into food, medicinal, toxic, aromatic or other uses. Finally, with the combinations of the scientific name of medicinal and toxic plants with information about their popular uses, a search was carried out in databases in order to indicate current pharmacological studies that reported evidences about the traditional uses described.

RESULTS

We found 28 women naturalists who participated in scientific expeditions or trips, or in a curiosity cabinet, or who were collectors of Natural History between the seventeenth and nineteenth centuries. All these women illustrated botanical species and/or recorded their everyday or medicinal use or reported their observations in the form of a published work, letters or diaries. Also, the trajectory of Maria Sibylla Merian revealed that her scientific relevance has been neglected from the eighteenth century by mechanisms of suppression, most of the time by male depreciation, which can be seen as a pattern for suppression of women in science. However, Maria Sibyllas' contributions have been valued again in the twenty-first century. In Maria Sibylla's work, 54 plants were identified, 26 of them used for food, 4 of them aromatic, 8 medicinal, 4 toxic and 9 other uses.

CONCLUSION

This study evidences that there are female naturalists whose work could be an important source for ethnopharmacological studies. Researching about women scientists, talking about them and highlighting the gender bias present in the scientific academy about the way the history of science is told is essential for the construction of a more diverse and richer scientific academy. The traditional use of 7 of 8 medicinal plants and 3 of 4 toxic plants reported was correlated with pharmacological studies, highlighting the importance of this historical record and its potential to direct strategic research in traditional medicine.

Chemical Composition, Antioxidant and Antibacterial Activities and Acute Toxicity of Cedrus atlantica, Chenopodium ambrosioides and Eucalyptus camaldulensis Essential Oils

The essential oils yield of Cedrus atlantica, Chenopodium ambrosioides and Eucalyptus camaldulensis was different. C. ambrosioides gave a relatively higher yield (2.1 ± 0.1%), while that of C. atlantica was low (1.0 ± 0.1%) and that of E. camaldulensis was lower (0.75 ± 0.1% of dry matter). The active ingredients of the essential oils and some of their biological effects were also determined. The characterization of their chemical compositions showed that the three essences have different chemical profiles: C. atlantica was richer in sesquiterpenes (β-Himachalene (54.21%) and γ -Himachalene (15.54%)), C. ambrosioides was very rich in monoterpene peroxides and monoterpenes (α-Terpinene (53.4%), ascaridole (17.7%) and ρ-Cymene (12.1%)) and E. camaldulensis was very rich in monoterpene compounds and monoterpenols (p-cymene (35.11%), γ-Eudesmol (11.9%), L-linalool (11.51%) and piperitone (10.28%)). The in vitro measurement of antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) reduction assay showed a significant performance of the eucalyptus oil and average performance of the other two (C. atlantica and C. ambrosioides). The in vitro bio-test for their antimicrobial effects showed that the antibacterial activity differed depending on the essential oil and the concentration used, and that their bactericidal efficacy was similar or superior to that of synthetic antibiotics. The toxicity test on rats revealed that the LD50 of the three essential oils was 500 mg/kg body weight, which classifies them as category four cytotoxic natural products at high doses.

Salt-Tolerant Plants as Sources of Antiparasitic Agents for Human Use: A Comprehensive Review

Parasitic diseases, especially those caused by protozoans and helminths, such as malaria, trypanosomiasis, leishmaniasis, Chagas disease, schistosomiasis, onchocerciasis, and lymphatic filariasis, are the cause of millions of morbidities and deaths every year, mainly in tropical regions. Nature has always provided valuable antiparasitic agents, and efforts targeting the identification of antiparasitic drugs from plants have mainly focused on glycophytes. However, salt-tolerant plants (halophytes) have lately attracted the interest of the scientific community due to their medicinal assets, which include antiparasitic properties. This review paper gathers the most relevant information on antiparasitic properties of halophyte plants, targeting human uses. It includes an introduction section containing a summary of some of the most pertinent characteristics of halophytes, followed by information regarding the ethnomedicinal uses of several species towards human parasitic diseases. Then, information is provided related to the antiprotozoal and anthelmintic properties of halophytes, determined by in vitro and in vivo methods, and with the bioactive metabolites that may be related to such properties. Finally, a conclusion section is presented, addressing perspectives for the sustainable exploitation of selected species.

Treating leishmaniasis in Amazonia, part 2: Multi-target evaluation of widely used plants to understand medicinal practices

ETHNOPHARMACOLOGICAL RELEVANCE

Leishmaniasis are widely distributed among tropical and subtropical countries, and remains a crucial health issue in Amazonia. Indigenous groups across Amazonia have developed abundant knowledge about medicinal plants related to this pathology.

AIM OF THE STUDY

We intent to explore the weight of different pharmacological activities driving taxa selection for medicinal use in Amazonian communities. Our hypothesis is that specific activity against Leishmania parasites is only one factor along other (anti-inflammatory, wound healing, immunomodulating, antimicrobial) activities.

MATERIALS AND METHODS

The twelve most widespread plant species used against leishmaniasis in Amazonia, according to their cultural and biogeographical importance determined through a wide bibliographical survey (475 use reports), were selected for this study. Plant extracts were prepared to mimic their traditional preparations. Antiparasitic activity was evaluated against promastigotes of reference and clinical New-World strains of Leishmania (L. guyanensis, L. braziliensis and L. amazonensis) and L. amazonensis intracellular amastigotes. We concurrently assessed the extracts immunomodulatory properties on PHA-stimulated human PBMCs and RAW264.7 cells, and on L. guyanensis antigens-stimulated PBMCs obtained from Leishmania-infected patients, as well as antifungal activity and wound healing properties (human keratinocyte migration assay) of the selected extracts. The cytotoxicity of the extracts against various cell lines (HFF1, THP-1, HepG2, PBMCs, RAW264.7 and HaCaT cells) was also considered. The biological activity pattern of the extracts was represented through PCA analysis, and a correlation matrix was calculated.

RESULTS

Spondias mombin L. bark and Anacardium occidentale L. stem and leaves extracts displayed high anti-promatigotes activity, with IC₅₀ ≤ 32 μg/mL against L. guyanensis promastigotes for S. mombin and IC₅₀ of 67 and 47 μg/mL against L. braziliensis and L. guyanensis promastigotes, respectively, for A. occidentale. In addition to the antiparasitic effect, antifungal activity measured against C. albicans and T. rubrum (MIC in the 16-64 μg/mL range) was observed. However, in the case of Leishmania amastigotes, the most active species were Bixa orellana L. (seeds), Chelonantus alatus (Aubl.) Pulle (leaves), Jacaranda copaia (Aubl.) D. Don. (leaves) and Plantago major L. (leaves) with IC₅₀ < 20 μg/mL and infection rates of 14-25% compared to the control. Concerning immunomodulatory activity, P. major and B. orellana were highlighted as the most potent species for the wider range of cytokines in all tested conditions despite overall contrasting results depending on the model. Most of the species led to moderate to low cytotoxic extracts except for C. alatus, which exhibited strong cytotoxic activity in almost all models. None of the tested extracts displayed wound healing properties.

CONCLUSIONS

We highlighted pharmacologically active extracts either on the parasite or on associated pathophysiological aspects, thus supporting the hypothesis that antiparasitic activities are not the only biological factor useful for antileishmanial evaluation. This result should however be supplemented by in vivo studies, and attracts once again the attention on the importance of the choice of biological models for an ethnophamacologically consistent study. Moreover, plant cultural importance, ecological status and availability were discussed in relation with biological results, thus contributing to link ethnobotany, medical anthropology and biology.

Polyphenol Composition and Antioxidant Activity of Tapirira guianensis Aubl. (Anarcadiaceae) Leaves

Tapirira guianensis (Anacardiaceae) is a natural resource from the Amazonian Forest and is locally known in French Guiana as “loussé” (creole), “tata pilili” (wayãpi), or “ara” (palikur). The tree is used by indigenous populations for medicinal purposes. To increase the potential of this tree for cosmetic, agro-food, or pharmaceutical uses, extracts were obtained through ultrasound-assisted extraction (UAE) from T. guianensis leaves using various extraction solvents such as water, methanol, and methanol–water (85/15; v/v). Chemical (DPPH, TEAC, ORAC) tests were applied to assess the anti-radical potential of these extracts. The polyphenol contents were determined by spectrophotometric (UV/Visible) and by means of chromatographic (UPLC-DAD-ESI-IT-MSⁿ) methods. Tapirira guianensis leaf hydromethanolic extract produced the highest polyphenol content and exhibited antiradical activities in chemical assays (DPPH, TEAC, and ORAC) similar to (or higher than) those of a well-known antiradical plant, green tea. In T. guianensis, two classes of polyphenols were evidenced: (1) galloylquinic acids (identified for the first time in the studied species) and (2) flavonols and flavanols (present in small amounts). Flavonols seemed to play a major role in the antioxidant activity of DPPH. These findings provide a rationale for the use of T. guianensis in traditional medicine and to pave the way for seeking new biological properties involving this Amazonian tree.

Phytochemical Analysis, Antispasmodic, Myorelaxant, and Antioxidant Effect of Dysphania ambrosioides (L.) Mosyakin and Clemants Flower Hydroethanolic Extracts and Its Chloroform and Ethyl Acetate Fractions

Dysphania ambrosioides (L.) Mosyakin and Clemants is an annual or ephemeral perennial herb used traditionally in the Mediterranean region in folk medicine to treat various illnesses, including those related to the digestive system. This study aims to assess the antispasmodic, myorelaxant, and antioxidant effects of D. ambrosioides flower hydroethanolic extract and its chloroform and ethyl acetate fractions in a comparative study to evaluate the result of the extraction type on the potential activity of the extract. Both rat and rabbit jejunum were used to evaluate the antispasmodic and myorelaxant effect, while the antioxidant effect was evaluated using DPPH, a ferric reducing power assay, and a beta-carotene bleaching test. LC/MS-MS analysis was carried out to reveal the composition of the different types of extract. Following the results, the hydroethanolic extract showed a significant myorelaxant effect (IC₅₀ = 0.39 ± 0.01 mg/mL). Moreover, it was shown that the hydroethanolic extract demonstrated the best antispasmodic activity (IC₅₀ = 0.51 ± 0.05 mg/mL), followed by the ethyl acetate (IC₅₀ = 4.05 ± 0.32 mg/mL) and chloroform (IC₅₀ = 4.34 ± 0.45 mg/mL) fractions. The antioxidant tests showed that the hydroethanolic extract demonstrated high antioxidant activity, followed by the ethyl acetate and chloroform fractions. The LC/MS-MS analysis indicates that the plant extract was rich in flavonoids, to which the extract activity has been attributed. This study supports the traditional use of this plant to treat digestive problems, especially those with spasms.

The effects of medicinal herbs and marine natural products on wound healing of cutaneous leishmaniasis: A systematic review

This study aimed to investigate the effects of medicinal herbs and marine natural products on wound healing of cutaneous leishmaniasis. To carry out this literature review, the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) instructions were used. Articles on the potential of medicinal plants and natural substances of marine origin against wound healing of cutaneous leishmaniasis were explored. The scientific databases considered were PubMed, Science Direct, Google Scholar, Web of Science, Scopus, and SpringerLink. The scientific documents collected were mainly scientific articles, books, book chapters, and doctoral thesis. The research considered 73 manuscripts published in the period from 1990 to 2020. From all the data collected, it appears that the scientific literature is rich in medicinal herbs and marine products to be valorized in the wound healing of cutaneous leishmaniasis. We have identified 15 medicinal plants traditionally used in the management of healing or ulcer of cutaneous leishmaniasis, 32 medicinal plants whose efficacy has been demonstrated in vitro or in vivo against cutaneous leishmaniasis, 5 marine products active against cutaneous leishmaniasis. It is also clear that the option of medicinal herbs/marine products in the management of cutaneous leishmaniasis is less expensive and allows to avoid the side effects of conventional products. It is necessary to encourage the development of dermatological topicals for the management of cutaneous leishmaniasis based on the data collected. In vivo research should be intensified on medicinal herbs traditionally used in wound healing of cutaneous leishmaniasis.

Cashew tree (Anacardium occidentale): Possible applications in dermatology

The potential uses of medicinal plants are far from exhausted, and one of the most important tools in the study of medicinal plants is the rescue of traditional knowledge, which, in Brazil, combines Indigenous, African, and European influences. The rich Brazilian ethnobotany, associated with the greatest biodiversity in the planet, constitutes a promising field of studies, albeit rather neglected in the medical community. The investigation of Anacardium occidentale applications in dermatology from the bibliographic survey of the specialty found the following activity: antileishmanial, anti-ophidic, antibiotic, antityrosinase, and antifungal in vitro. Studies associating A occidentale and dermatology in medical literature seem incipient, and there is a lack of studies in humans. In vitro studies are useful as an initial step, but they are irrelevant if they do not develop into viable formulations that can be tested in humans.

Ethnomedical uses, chemical constituents, and evidence-based pharmacological properties of Chenopodium ambrosioides L.: extensive overview

Background

The Chenopodium genus is a plant family widely spread worldwide that includes various plant species reputed to possess several medicinal virtues in folk medicines. Chenopodium ambrosioides L. is among the most used plants in traditional medicines worldwide. This review aimed to highlight ethnomedicinal uses, phytochemical status, and pharmacological properties of C. ambrosioides L.

Main body of the abstract

The analysis of relevant data highlights various ethnomedicinal uses against human and veterinary diseases in forty countries. Most indications consisted of gastrointestinal tract dysfunctioning troubles and worms parasitemia. Around 330 chemical compounds have been identified in different plant parts, especially in its essential oil fractions (59.84%). However, only a few compounds—mainly monoterpenes and glycosides—have been isolated and characterized. Experimental pharmacological studies validated a large scale of significant health benefits. It appeared that many monoterpenes are antioxidant, insecticidal, trypanocidal, analgesic, antifungal, anti-inflammatory, anti-arthritic, acaricidal, amoebicidal, anthelmintic, anticancer, antibacterial, antidiabetic, antidiarrheal, antifertility, antifungal, anti-leishmanial, antimalarial, antipyretic, antisickling, antischistosomal, antiulcer, anxiolytic, immunomodulatory, molluscicidal, and vasorelaxant agents.

Short conclusion

Thus, the Chenopodium ambrosioides species necessitates further chemical studies to isolate and characterize new bioactive secondary metabolites and pharmacological investigations to precise the mechanisms of action before clinical trials.

The Potential of Traditional Knowledge to Develop Effective Medicines for the Treatment of Leishmaniasis

Leishmaniasis is a neglected tropical disease that affects people living in tropical and subtropical areas of the world. There are few therapeutic options for treating this infectious disease, and available drugs induce severe side effects in patients. Different communities have limited access to hospital facilities, as well as classical treatment of leishmaniasis; therefore, they use local natural products as alternative medicines to treat this infectious disease. The present work performed a bibliographic survey worldwide to record plants used by traditional communities to treat leishmaniasis, as well as the uses and peculiarities associated with each plant, which can guide future studies regarding the characterization of new drugs to treat leishmaniasis. A bibliographic survey performed in the PubMed and Scopus databases retrieved 294 articles related to traditional knowledge, medicinal plants and leishmaniasis; however, only 20 were selected based on the traditional use of plants to treat leishmaniasis. Considering such studies, 378 quotes referring to 292 plants (216 species and 76 genera) that have been used to treat leishmaniasis were recorded, which could be grouped into 89 different families. A broad discussion has been presented regarding the most frequent families, including Fabaceae (27 quotes), Araceae (23), Solanaceae and Asteraceae (22 each). Among the available data in the 378 quotes, it was observed that the parts of the plants most frequently used in local medicine were leaves (42.3% of recipes), applied topically (74.6%) and fresh poultices (17.2%). The contribution of Latin America to studies enrolling ethnopharmacological indications to treat leishmaniasis was evident. Of the 292 plants registered, 79 were tested against Leishmania sp. Future studies on leishmanicidal activity could be guided by the 292 plants presented in this study, mainly the five species Carica papaya L. (Caricaceae), Cedrela odorata L. (Meliaceae), Copaifera paupera (Herzog) Dwyer (Fabaceae), Musa × paradisiaca L. (Musaceae), and Nicotiana tabacum L. (Solanaceae), since they are the most frequently cited in articles and by traditional communities.

Pharmacological Assessment of the Carvacrol Chemotype Essential Oil FromPlectranthus amboinicusGrowing in Cuba

Plant-derived products are employed in various public health practices and have been considered as a major source of medicines. The genus Plectranthus (Lamiaceae) has been widely respected for its nutritional properties, its essential oil, and its therapeutic values. In the present work, the chemical characterization, antimicrobial, antiparasitic, and cytotoxic properties of the essential oil from Plectranthus amboinicus (Lour.) Spreng and its main compound carvacrol were studied. Twenty-one components were identified in the oil by gas chromatography coupled with a mass spectrometric detector. In this oil, carvacrol constitutes the major compound (71%), which represented the more abundant chemotype. The essential oil did not inhibit growth of Escherichia coli, Staphylococcus aureus, Candida albicans, Trypanosoma cruzi, or Leishmania infantum, but displayed activity against Plasmodium falciparum (half-maximal inhibitory concentration [IC50] = 5.9 µg/mL), Trypanosoma brucei (IC50= 34.9 µg/mL), and Leishmania amazonensis (IC50= 58.2 µg/mL), and the human tumor-derived cell lines MCF-7 (IC50= 29.1 µg/mL), MDA-MB-231 (IC50= 41.5 µg/mL), and 22Rv1 (IC50= 29.6 µg/mL), but no cytotoxicity was observed against nonmalignant macrophages. The antiproliferative activity of the oil could be attributed to carvacrol. However, this compound showed certain level of cytotoxicity, which suggests unspecific activity. This study provides evidence about antimicrobial and anticancer potential of the essential oil from P. amboinicus against protozoa and neoplastic diseases, particularly as an antimalarial natural product.

Antioxidant property of Plantago major leaf extracts reduces testicular torsion/detorsion-induced ischemia/reperfusion injury in rats

The present study was aimed to determine the protective effects of Plantago major L (PM) leaf extracts on the testicular torsion/detorsion (T/D)-induced ischemia/reperfusion (I/R) injury in rats. Twenty-four mature male Sprague-Dawley rats, weighing 200-220 g, were selected. They were randomly divided into four groups of six animals each: Sham (sham-operated rats; all the surgical steps were performed but T/D was not induced), TDC (Control group; T/D was induced and the right testicular torsion of 720° lasting two hours was followed by detorsion), TDP50 (T/D-operated rats received 50.00 mg kg-1 of PM extract daily for seven days intraperitoneally after detorsion) and TDP100 (T/D-operated rats received 100 mg kg-1 of PM extract daily for seven days intraperitoneally after detorsion). After seven days of treatment, the right testicles were collected. Histopathological and biochemical analyses including levels of malondialdehyde (MDA) and catalase (CAT) and peroxidase activities were determined in testicular tissues of the rats. Tissue sections were taken from testis, Hematoxylin-Eosin staining was done, and the slides were examined by a light microscope. The level of MDA was significantly increased in the testes of the TDC group. The CAT activity levels were decreased significantly after I/R. The post-torsion treatment with PM, particularly at 100 mg kg-1, prevented the increase in lipid peroxidation and reduced the CAT activity levels. The PM also prevented I/R-induced cellular damage and histological changes in the testicular tissues. According to the results of the current study, PM leaf extracts had significant positive effects on the testicular T/D-induced I/R injury. The possible mechanism of reduction in biochemical and histological injuries by PM extracts could be due to antioxidant property.

Anti-cholinesterase potential of diverse botanical families from Malaysia: Evaluation of crude extracts and fractions from liquid-liquid extraction and acid-base fractionation

ETHNOPHARMACOLOGICAL RELEVANCE

Enhancement of cholinergic functions in the brain via acetylcholinesterase inhibition is one of the main therapeutic strategies to improve symptoms associated with Alzheimer's or related cognitive deficits. There is a pathophysiological correlation between Alzheimer's and Diabetes Mellitus, as well as inflammation and oxidative stress that may cause cognitive decline.

AIM OF THE STUDY

The present study was intended to evaluate anti-cholinesterase potential of 177 Malaysian plant extracts from 148 species known to have related ethnomedicinal uses such as anti-inflammatory, anti-oxidant, anti-diabetic, epilepsy, headache, memory enhancement and anti-aging.

MATERIALS AND METHODS

Anti-cholinesterase screening against both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes was performed on the basis of in-vitro colorimetric 96-well microplate-based assay method. Potent active plant extracts were subjected to liquid-liquid extraction and acid-base fractionation for further analysis.

RESULTS

Fifty-seven plant extracts exhibited potent anti-cholinesterase activities (50-100% inhibition) at 200 μg/ml. Majority of the active plants originated from Fabaceae family. Coccoloba uvifera (L.) L. stem extract manifested the lowest IC₅₀ of 3.78 μg/ml for AChE and 5.94 μg/ml for BChE. A few native species including Tetracera indica (Christm. & Panz.) Merr., Cyrtostachys renda Blume and Ixora javanica (Blume) DC. showed cholinesterase inhibition despite limited local medical applications. Further anti-AChE evaluation (50 μg/ml) of 18 potent plant extracts harbored active polar components in butanol and water fractions, except Senna pendula (Willd.) H.S.Irwin & Barneby (leaves and stems), Acacia auriculiformis Benth. (leaves), Artocarpus altilis (Parkinson ex F.A.Zorn) Fosberg (leaves), and Macaranga tanarius (L.) Mull.Arg. (leaves) that showed inhibitory activity in less polar fractions. The acidic extraction of these four plant species improved their inhibition level against AChE.

CONCLUSION

This study rendered a preliminary overview of anti-cholinesterase activity from diverse Malaysian botanical families in which provided the medical relevance toward these native plant species, especially ones with limited ethnobotanical record or practice.

Essential Oil from Chenopodium ambrosioides as a Promising Antileishmanial Agent

Chenopodium ambrosioides has been used traditionally against parasitic diseases. The essential oil of the plant is a complex mixture of compounds with a rich structural diversity. This review focuses on recent evaluation of the essential oil from C. ambrosioides as a promising antileishmanial agent. The tested product showed activity against promastigotes and amastigotes of Leishmania amazonensis and L. donovani. An optimal dose of 30 mg/Kg was effective by intraperitoneal and oral routes in experimental cutaneous leishmaniasis. The chenopodium oil had a moderate toxicity against peritoneal macrophages of BALB/c mice and no side effects were detected in animals treated by the oral route. Isolates of L. amazonensis from treated mice were susceptible to the essential oil. Synergic effects were observed when the essential oil was incubated in conjunction with pentamidine on L. amazonensis promastigote cultures. Future studies focusing on formulation, toxicity and mechanism of action may help in the development of chenopodium oil as a new antileishmanial drug.

Carapa guianensis Aublet (Andiroba) Seed Oil: Chemical Composition and Antileishmanial Activity of Limonoid-Rich Fractions

Leishmaniasis is a complex of diseases caused by protozoa of the genus Leishmania and affects millions of people around the world. Several species of plants are used by traditional communities for the treatment of this disease, among which is Carapa guianensis Aubl. (Meliaceae), popularly known as andiroba. The objective of the present work was to conduct a chemical study of C. guianensis seed oil and its limonoid-rich fractions, with the aim of identifying its secondary metabolites, particularly the limonoids, in addition to investigating its anti-Leishmania potential. The chemical analyses of the C. guianensis seed oil and fractions were obtained by electrospray ionization mass spectrometry (ESI-MS). The cytotoxic activity was tested against peritoneal macrophages, and antileishmanial activity was evaluated against promastigotes and intracellular amastigotes of Leishmania amazonensis. All the C. guianensis seed oil samples analyzed exhibited the same pattern of fatty acids, while the limonoids 7-deacetoxy-7-hydroxygedunin, deacetyldihydrogedunin, deoxygedunin, andirobin, gedunin, 11β-hydroxygedunin, 17-glycolyldeoxygedunin, 6α-acetoxygedunin, and 6α,11β-diacetoxygedunin were identified in the limonoid-rich fractions of the oil. The C. guianensis seed oil did not exhibit antileishmanial activity, and cytotoxicity was higher than 1000 μg/mL. Three limonoid-rich oil fractions demonstrated activity against promastigotes (IC50 of 10.53±0.050, 25.3±0.057, and 56.9±0.043μg/mL) and intracellular amastigotes (IC50 of 27.31±0.091, 78.42±0.086, and 352.2±0.145 μg/mL) of L. amazonensis, as well as cytotoxicity against peritoneal macrophages (CC50 of 78.55±1.406, 139.0±1.523, and 607.7±1.217 μg/mL). The anti-Leishmania activity of the limonoid-rich fractions of C. guianensis can be attributed to the limonoids 11β-hydroxygedunin and 6α,11β-diacetoxygedunin detected in the chemical analysis.

Review on medicinal plants and natural compounds as anti-Onchocerca agents

Onchocerciasis is a filarial vector borne disease which affects several million people mostly in Africa. The therapeutic approach of its control was based on a succession of drugs which always showed limits. The last one: ivermectin is not the least. It was shown to be only microfilaricidal and induced resistance to the human parasite Onchocerca volvulus. The approach using medicinal plants used in traditional medicine is a possible alternative method to cure onchocerciasis. Onchocerca ochengi and Onchocerca gutturosa are the parasite models used to assess anthelmintic activity of potentially anthelmintic plants. Numerous studies assessed the in vitro and/or in vivo anthelmintic activity of medicinal plants. Online electronic databases were consulted to gather publications on in vitro and in vivo studies of anti-Onchocerca activity of plants from 1990 to 2017. Globally, 13 plant families were investigated for anti-Onchocerca activity in 13 studies. The most active species were Anacardium occidentale, Euphorbia hirta and Acacia nilotica each with an LC₅₀ value of 2.76, 6.25 and 1.2 μg/mL, respectively. Polycarpol, voacamine, voacangine, ellagic acid, gallic acid, gentisic acid, 3-O-acetyl aleuritolic acid and (-)-epigallocatechin 3-O-gallate were the isolated plant compounds with anti-Onchocerca activity. Most of the assessed extract/compounds showed a good safety after in vivo acute toxicity assays and/or in vitro cytotoxicity test. The exception was the ethanol extract of Trichilia emetica, which killed completely and drastically mice at a dose of 3000 mg/kg. Several plant groups of compounds were shown active against Onchocerca sp. such as tannins, alkaloids, triterpenoids and essential oils. Nevertheless, none of the active compounds was subjected to clinical trial, to assessment of its diffusibility through nodular wall or its capability to induce genetic resistance of Onchocerca sp.

Interaction of ascaridole, carvacrol, and caryophyllene oxide from essential oil of Chenopodium ambrosioides L. with mitochondria in Leishmania and other eukaryotes

The antileishmanial activity of the essential oil (EO) from Chenopodium ambrosioides L. has been demonstrated in vitro and in animal models, attributed to the major components of the EO. This study focused on the effects of the three major EO compounds carvacrol, caryophyllene oxide (Caryo), and the antileishmanial endoperoxide ascaridole (Asc) on mitochondrial functions in Leishmania tarentolae promastigotes (LtP). EO and Caryo were able to partially inhibit the leishmanial electron transport chain, whereas other components failed to demonstrate a direct immediate effect. Caryo demonstrated inhibition of complex III activity in LtP and in isolated complex III from other species. The formation of superoxide radicals was studied in Leishmania by electron spin resonance spectroscopy in the presence of iron chelators wherein selected compounds failed to trigger a significant immediate additional superoxide production in LtP. However, upon prolonged incubation of Leishmania with Asc and especially in the absence of iron chelators (allowing the activation of Asc), an increased superoxide radical production and significant impairment of mitochondrial coupling in Leishmania was observed. Prolonged incubation with all EO components resulted in thiol depletion. Taken together, the major components of EO mediate their leishmanicidal activity via different mitochondrial targets and time profiles. Further studies are required to elucidate possible synergistic effects of carvacrol and Asc and the influence of minor compounds.

Anti-inflammatory and bronchodilatory constituents of leaf extracts of Anacardium occidentale L. in animal models

OBJECTIVE

Anacardium occidentale L. leaf is useful in the treatment of inflammation and asthma, but the bioactive constituents responsible for these activities have not been characterized. Therefore, this study was aimed at identifying the bioactive constituent(s) of A. occidentale ethanolic leaf extract (AOEL) and its solvent-soluble portions, and evaluating their effects on histamine-induced paw edema and bronchoconstriction.

METHODS

The bronchodilatory effect was determined by measuring the percentage protection provided by plant extracts in the histamine-induced bronchoconstriction model in guinea pigs. The anti-inflammatory effect of the extracts on histamine-induced paw edema in rats was determined by measuring the increase in paw diameter, after which the percent edema inhibition was calculated. The extracts were analyzed using gas chromatography-mass spectrometry to identify the bioactive constituents. Column chromatography and Fourier transform infrared spectroscopy were used respectively to isolate and characterize the constituents. The bronchodilatory and anti-inflammatory activities of the isolated bioactive constituent were evaluated.

RESULTS

Histamine induced bronchoconstriction in the guinea pigs and edema in the rat paw. AOEL, hexane-soluble portion of AOEL, ethyl acetate-soluble portion of AOEL, and chloroform-soluble portion of AOEL significantly increased bronchodilatory and anti-inflammatory activities (P < 0.05). Oleamide (9-octadecenamide) was identified as the most abundant compound in the extracts and was isolated. Oleamide significantly increased bronchodilatory and anti-inflammatory activities by 32.97% and 98.41%, respectively (P < 0.05).

CONCLUSION

These results indicate that oleamide is one of the bioactive constituents responsible for the bronchodilatory and anti-inflammatory activity of A. occidentale leaf, and can therefore be employed in the management of bronchoconstriction and inflammation.

Chemical Composition, Antibacterial, Schistosomicidal, and Cytotoxic Activities of the Essential Oil of Dysphania ambrosioides (L.) Mosyakin & Clemants (Chenopodiaceae)

We have investigated the chemical composition and the antibacterial activity of the essential oil of Dysphania ambrosioides (L.) Mosyakin & Clemants (Chenopodiaceae) (DA-EO) against a representative panel of cariogenic bacteria. We have also assessed the in vitro schistosomicidal effects of DA-EO on Schistosoma mansoni and its cytotoxicity to GM07492-A cells in vitro. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS) revealed that the monoterpenes cis-piperitone oxide (35.2%), p-cymene (14.5%), isoascaridole (14.1%), and α-terpinene (11.6%) were identified by as the major constituents of DA-EO. DA-EO displayed weak activity against Streptococcus sobrinus and Enterococcus faecalis (minimum inhibitory concentration (MIC) = 1000 μg/ml). On the other hand, DA-EO at 25 and 12.5 μg/ml presented remarkable schistosomicidal action in vitro and killed 100% of adult worm pairs within 24 and 72 h, respectively. The LC₅₀ values of DA-EO were 6.50 ± 0.38, 3.66 ± 1.06, and 3.65 ± 0.76 μg/ml at 24, 48, and 72 h, respectively. However, DA-EO at concentrations higher than 312.5 μg/ml significantly reduced the viability of GM07492-A cells (IC₅₀  = 207.1 ± 4.4 μg/ml). The selectivity index showed that DA-EO was 31.8 times more toxic to the adult S. mansoni worms than GM07492-A cells. Taken together, these results demonstrate the promising schistosomicidal potential of the essential oil of Dysphania ambrosioides.

Antinociceptive pharmacological profile of Dysphania graveolens in mouse

This work evaluates the potential antinociceptive activity of Dysphania graveolens, traditional medicinal plant used in Mexico to treat stomach pain. A CH₂Cl₂-MeOH extract, infusion and essential oil from aerial parts of Dysphania graveolens were evaluated in hot plate and writhing tests in mice. The metabolites pinostrobin, pinocembrin and chrysin were isolated from the Dysphania graveolens infusion; next, they were evaluated in both nociceptive tests. To confirm the antinociceptive activity and explore the possible participation of opioid, GABA and serotonin receptors in the pharmacological mechanism, a formalin test was used. Oral administration of Dysphania graveolens CH₂Cl₂-MeOH extract, infusion and essential oil (31-316mg/kg) produced an antinociceptive response to thermic and chemical algesic stimuli. Essential oil was the most active partition of this plant. In addition, the secondary metabolites pinostrobin, pinocembrin and chrysin possess a significant antinociceptive effect. This response was confirmed by the formalin test for the CH₂Cl₂-MeOH extract of Dysphania graveolens and chrysin. In both cases, the antinociceptive activity was reverted in the presence of naltrexone, flumazenil and bicuculline antagonists. The 5-HT_2A/2C receptors did not participate in the antinociceptive response of this plant. The overall information tends to support the efficacy of Dysphania graveolens as an analgesic and its cultural use in abdominal pain.

Treating leishmaniasis in Amazonia: A review of ethnomedicinal concepts and pharmaco-chemical analysis of traditional treatments to inspire modern phytotherapies

ETHNOPHARMACOLOGICAL RELEVANCE

Cutaneous and mucocutaneous leishmaniasis are neglected tropical diseases that occur in all intertropical regions of the world. Amazonian populations have developed an abundant knowledge of the disease and its remedies. Therefore, we undertook to review traditional antileishmanial plants in Amazonia and have developed new tools to analyze this somewhat dispersed information.

MATERIAL AND METHODS

A literature review of traditional remedies for cutaneous/mucocutaneous leishmaniasis in the Amazon was conducted and the data obtained was used to calculate distribution indexes designed to highlight the most relevant uses in Amazonia. The cultural distribution index represents the distribution rate of a given taxon among different cultural groups and was calculated as the ratio of the number of groups using the taxon to the total number of groups cited. The geographical distribution index allowed us to quantify spatial distribution of a taxon's uses in Amazonia and was calculated geometrically by measuring the average distance between the points where uses have been reported and the barycenter of those points. The general distribution index was defined as an arithmetic combination of the previous two and provides information on both cultural and spatial criteria.

RESULTS

475 use reports, concerning 291 botanical species belonging to 83 families have been gathered depicted from 29 sources. Uses concern 34 cultural groups. While the use of some taxa appears to be Pan-Amazonian, some others are clearly restricted to small geographical regions. Particular attention has been paid to the recipes and beliefs surrounding treatments. Topical application of the remedies dominated the other means of administration and this deserves particular attention as the main treatments against Neotropical leishmaniasis are painful systemic injections. The data set was analyzed using the previously defined distribution indexes and the most relevant taxa were further discussed from a phytochemical and pharmacological point of view.

CONCLUSIONS

The Amazonian biodiversity and cultural heritage host a fantastic amount of data whose systematic investigation should allow a better large-scale understanding of the dynamics of traditional therapies and the consequent discovery of therapeutic solutions for neglected diseases. Distribution indices are indeed powerful tools for emphasizing the most relevant treatments against a given disease and should be very useful in the meta-analysis of other regional pharmacopeia. This focus on renowned remedies that have not yet benefitted from extended laboratory studies, could stimulate future research on new treatments of natural origin for leishmaniasis.

Plectranthus amboinicus (Lour.) Spreng: Botanical, Phytochemical, Pharmacological and Nutritional Significance

Plectranthus amboinicus (Lour.) Spreng. is a perennial herb belonging to the family Lamiaceae which occurs naturally throughout the tropics and warm regions of Africa, Asia and Australia. This herb has therapeutic and nutritional properties attributed to its natural phytochemical compounds which are highly valued in the pharmaceutical industry. Besides, it has horticultural properties due to its aromatic nature and essential oil producing capability. It is widely used in folk medicine to treat conditions like cold, asthma, constipation, headache, cough, fever and skin diseases. The leaves of the plant are often eaten raw or used as flavoring agents, or incorporated as ingredients in the preparation of traditional food. The literature survey revealed the occurrence 76 volatiles and 30 non-volatile compounds belonging to different classes of phytochemicals such as monoterpenoids, diterpenoids, triterpenoids, sesquiterpenoids, phenolics, flavonoids, esters, alcohols and aldehydes. Studies have cited numerous pharmacological properties including antimicrobial, antiinflammatory, antitumor, wound healing, anti-epileptic, larvicidal, antioxidant and analgesic activities. Also, it has been found to be effective against respiratory, cardiovascular, oral, skin, digestive and urinary diseases. Yet, scientific validation of many other traditional uses would be appreciated, mainly to discover and authenticate novel bioactive compounds from this herb. This review article provides comprehensive information on the botany, phytochemistry, pharmacology and nutritional importance of P. amboinicus essential oil and its various solvent extracts. This article allows researchers to further explore the further potential of this multi-utility herb for various biomedical applications.

In vitro evaluation of traditionally used Surinamese medicinal plants for their potential anti-leishmanial efficacy

ETHNOPHARMACOLOGICAL RELEVANCE

Plant-based preparations are extensively used in Surinamese folk medicine for treating leishmaniasis, but often without a scientific rationale.

AIM OF THE STUDY

To evaluate 25 Surinamese medicinal plants for their potential efficacy against leishmaniasis.

MATERIALS AND METHODS

Concentrated plant extracts were evaluated for their effect on the viability of L. (V.) guyanensis AMC, L. (L.) major NADIM5, and L. (L.) donovani GEDII promastigotes, as well as intracellular amastigotes of L. (L.) donovani BHU814 in infected THP-1 cells. Selectivity was assessed by cytotoxicity against THP-1 cells.

RESULTS

The only plant extract that showed potentially meaningful anti-leishmanial activity was that from Solanum lycocarpum that displayed mean IC50 values of about 51, 61, and <16 µg/mL against L. (V) guyanensis, L. (L) major, and L. (L) donovani promastigotes, respectively; about 374 µg/mL against L. (L) donovani amastigotes; and >500 µg/mL against THP-1 cells. The Bryophyllum pinnatum, Inga alba, and Quassia amara extracts displayed moderate to high IC50 values against promastigotes (about 51 to >500 µg/mL) and/or amastigotes (about 224 to >500 µg/mL) but were relatively toxic to THP-1 cells (IC50 values <16 to about 42 µg/mL). The remaining plant extracts exhibited in many cases IC50 values close to, around, or above 500µg/mL against promastigotes, amastigotes, and THP-1 cells.

CONCLUSIONS

The S. lycocarpum preparation may be useful against leishmaniasis and may have a good safety index, warranting further investigations into its active constituents and mechanism(s) of action.

The Effect of Ursolic Acid on Leishmania (Leishmania) amazonensis Is Related to Programed Cell Death and Presents Therapeutic Potential in Experimental Cutaneous Leishmaniasis

Among neglected tropical diseases, leishmaniasis is one of the most important ones, affecting more than 12 million people worldwide. The available treatments are not well tolerated, and present diverse side effects, justifying the search for new therapeutic compounds. In the present study, the activity of ursolic acid (UA) and oleanolic acid (OA) were assayed in experimental cutaneous leishmaniasis (in vitro and in vivo). Promastigote forms of L. amazonensis were incubated with OA and UA for 24h, and effective concentration 50% (EC50) was estimated. Ultraestructural alterations in Leishmania amazonensis promastigotes after UA treatment were evaluated by transmission electron microscopy, and the possible mode of action was assayed through Annexin V and propidium iodide staining, caspase 3/7 activity, DNA fragmentation and transmembrane mitochondrial potential. The UA potential was evaluated in intracellular amastigotes, and its therapeutic potential was evaluated in L. amazonensis infected BALB/c mice. UA eliminated L. amazonensis promastigotes with an EC50 of 6.4 μg/mL, comparable with miltefosine, while OA presented only a marginal effect on promastigote forms at 100 μg/mL. The possible mechanism by which promastigotes were eliminated by UA was programmed cell death, independent of caspase 3/7, but it was highly dependent on mitochondria activity. UA was not toxic for peritoneal macrophages from BALB/c mice, and it was able to eliminate intracellular amastigotes, associated with nitric oxide (NO) production. OA did not eliminate amastigotes nor trigger NO. L. amazonensis infected BALB/c mice submitted to UA treatment presented lesser lesion size and parasitism compared to control. This study showed, for the first time, that UA eliminate promastigote forms through a mechanism associated with programed cell death, and importantly, was effective in vivo. Therefore, UA can be considered an interesting candidate for future tests as a prototype drug for the treatment of cutaneous leishmaniasis.

Cytotoxicity of medicinal plants of the West-Canadian Gwich׳in Native Americans towards sensitive and multidrug-resistant cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional medicine of the Native Americans has a long tradition of medicinal plants, which also influenced modern oncology. For instance, podophyllotoxin the active ingredient of Podophyllum peltatum L. (Berberidaceae) used by Native Americans to treat warts led to the development of etoposide and teniposide. In the present investigation, we studied 10 medicinal plants used by the Gwich׳in First Nation of West-Canada, which have been used against diverse diseases including cancer.

MATERIAL AND METHODS

Sensitive and multidrug-resistant (MDR) tumor cell lines expressing various ATP-binding cassette (ABC) transporters (P-glycoprotein/ABCB1/MDR1, MRP1/ABCC1, or BCRP/ABCG2) have been used. Cytotoxicity was determined by the resazurin assay.

RESULTS

Arctium minus Bernh. (Asteraceae). Lysichiton americanus Hultén & St. John (Araceae), and Maianthemum dilatatum (Alph.Wood) A.Nelson & J.F.Macbr.(Asparagaceae) were cytotoxic with IC50 values ranging from 2.40 to 86.35 µg/mL. The MDR cell lines did not exert cross-resistance to these extracts.

CONCLUSION

As these medicinal plants of the West-Canadian Gwich׳in First Nation were not involved in classical drug resistance mechanisms and might therefore be valuable to bypass anticancer drug resistance in refractory tumors.

Antileishmanial Potential of Tropical Rainforest Plant Extracts

A total of 115 different plant extracts from our collection, representing 96 plant species, have been evaluated for in vitro antileishmanial activity against L. amazonensis promastigotes. In addition, the extracts were screened for cytotoxic activity against BALB/c mouse macrophages in order to assess a selectivity index. Crude extracts that showed a selectivity index (CC50 for macrophage / IC50 for promastigotes) ³ 5 or with IC50 < 12.5 μg/mL against promastigotes, a total of 28 extracts, were further screened for anti-amastigote activity. A total of 25 extracts showed promising activity against L. amazonensis promastigotes with low cytotoxic activity. Ten of these extracts showed selectivity indices, (CC50 for macrophages / IC50 for amastigotes) greater than 10 and are considered "hits", worthy candidates for further phytochemical exploration: Conostegia xalapensis methanol bark extract, Endiandra palmerstonii bark extract, Eugenia monteverdensis acetone bark extract, Eugenia sp. "fine leaf" acetone bark extract, Exothea paniculata chloroform bark extract, Mallotus paniculatus ethanol bark extract, Matelea pseudobarbata ethanol extract, Quercus insignis ethanol bark extract, Sassafras albidum dichloromethane bark extract, and Stemmadenia donnell-smithii acetone bark extract.

Antileishmanial activity of medicinal plants used in endemic areas in northeastern Brazil

This study investigates the leishmanicidal activity of five species of plants used in folk medicine in endemic areas of the state of Alagoas, Brazil. Data were collected in the cities of Colonia Leopoldina, Novo Lino, and União dos Palmares, Alagoas state, from patients with cutaneous leishmaniasis (Leishmania amazonensis) who use medicinal plants to treat this disease. Plants extracts were tested at a concentration of 1–100 μg/mL in all experiments, except in an assay to evaluate activity against amastigotes, when 10 μg/mL was used. All plants extracts did not show deleterious activity to the host cell evidenced by LDH assay at 100, 10, and 1 μg/mL after 48 h of incubation. The plants extracts Hyptis pectinata (L.) Poit, Aloe vera L., Ruta graveolens L., Pfaffia glomerata (Spreng.) Pedersen, and Chenopodium ambrosioides L. exhibited direct activity against extracellular forms at 100 μg/mL; these extracts inhibited growth by 81.9%, 82.9%, 74.4%, 88.7%, and 87.4%, respectively, when compared with promastigotes. The plants extracts H. pectinata, A. vera, and R. graveolens also significantly diminished the number of amastigotes at 10 μg/mL, inhibiting growth by 85.0%, 40.4%, 94.2%, and 97.4%, respectively, when compared with control. Based on these data, we conclude that the five plants exhibited considerable leishmanicidal activity.

Antileishmanial activity of essential oil from Chenopodium ambrosioides and its main components against experimental cutaneous leishmaniasis in BALB/c mice

Chenopodium ambrosioides have been used during centuries by native people to treat parasitic diseases.

AIMS OF THE STUDY

To compare the in vivo anti-leishmanial activity of the essential oil (EO) from C. ambrosioides and its major components (ascaridole, carvacrol and caryophyllene oxide).

MATERIALS AND METHODS

Anti-leishmanial effect was evaluated in BALB/c mice infected with Leishmania amazonensis and treated with the EO, main compounds and artificial mix of pure components by intralesional route at 30 mg/kg every 4 days during 14 days. Diseases progression and parasite burden in infected tissues were determined.

RESULTS

EO prevented lesion development compared (p<0.05) with untreated animals and treated with vehicle. In addition, the efficacy of EO was also statistically superior (p<0.05) compared with the glucantime-treated animals. No potential effects were observed with pure components treatment. Mix of pure compounds cause death of animals after 3 days of treatment.

CONCLUSIONS

Our results demonstrate the superiority of EO against experimental cutaneous leishmaniasis caused by L. amazonensis.

Acute and sub-chronic toxicity of aqueous extracts of Chenopodium ambrosioides leaves in rats

The present study aimed to evaluate the toxicity of aqueous extract of Chenopodium ambrosioides leaves. To measure acute toxicity, rats were administered 0, 0.3, 1.0, or 3.0 g/kg of aqueous extract from C. ambrosioides leaves by gavage. To analyze sub-chronic toxicity, rats were treated by oral gavage for 15 consecutive days with 0, 0.3, or 1.0 g/kg of extract of C. ambrosioides leaves. No animals from either trial exhibited any signs of toxicity. In the acute study, the highest dose of the extract led to an increase in the serum activities of alanine transaminase (ALT) and aspartate transaminase (AST) and a decrease in the serum levels of urea. In the sub-chronic test, rats treated with 1.0 g/kg for 15 days exhibited increased serum ALT activity and creatinine levels and mild cytoplasmic vacuolation of hepatocytes. The results indicate that aqueous extract from C. ambrosioides leaves produce slight hepatotoxic lesions in rats.

Antiparasitic activity and effect of casearins isolated from Casearia sylvestris on Leishmania and Trypanosoma cruzi plasma membrane

Leishmaniasis and Chagas disease are infectious diseases caused by parasite Leishmania sp. and Trypanosoma cruzi, respectively, and are included among the most neglected diseases in several underdeveloped and developing countries, with an urgent demand for new drugs. Considering the antiparasitic potential of MeOH extract from leaves of Casearia sylvestris Sw. (Salicaceae), a bioguided fractionation was conducted and afforded four active clerodane diterpenes (casearins A, B, G, and J). The obtained results indicated a superior efficacy of tested casearins against trypomastigotes of T. cruzi, with IC50 values ranging from 0.53 to 2.77 μg/ml. Leishmania infantum promastigotes were also susceptible to casearins, with IC50 values in a range between 4.45 and 9.48 μg/ml. These substances were also evaluated for mammalian cytotoxicity against NCTC cells resulting in 50% cytotoxic concentrations (CC50) ranging from 1.46 to 13.76 μg/ml. Additionally, the action of casearins on parasite membranes was investigated using the fluorescent probe SYTOX Green. The obtained results demonstrated a strong interaction of casearins A and B to the plasma membrane of T. cruzi parasites, corroborating their higher efficacy against these parasites. In contrast, the tested casearins induced no alteration in the permeability of plasma membrane of Leishmania parasites, suggesting that biochemical differences between Leishmania and T. cruzi plasma membrane might have contributed to the target effect of casearins on trypomastigotes. Thus, considering the importance of studying novel and selective drug candidates against protozoans, casearins A, B, G, and J could be used as tools to future drug design studies.

Chemical constituents of Plectranthus amboinicus and the synthetic analogs possessing anti-inflammatory activity

This study demonstrates that compounds 1-4 from an extract of Plectranthus amboinicus inhibit the binding of AP-1 to its consensus DNA sequence. Thymoquinone (5) was further identified as a nonpolar ingredient from the hexane extract of P. amboinicus to suppress the expression of lipopolysaccharide-induced tumor necrosis factor-alpha (TNF-α). We then synthesized 2-alkylidenyl-4-cyclopentene-1,3-diones as the designed biomimetics of thymoquinone, and found that compounds 8a, 8b and 8d were more potent TNF-α inhibitors.

Antiproliferative activity of Solanum lycocarpum alkaloidic extract and their constituents, solamargine and solasonine, in tumor cell lines

Natural products are some of the important sources of new anticancer drugs. The Brazilian flora is considered one of the most diverse in the word, although not many large-scale pharmacological and phytochemical studies have been conducted to date. With this in mind, in the present study we evaluated the antiproliferative activity of Solanum lycocarpum fruit glycoalkaloid extract (SL) and its major compounds, solamargine (SM) and solasonine (SS), against different tumor cell lines: murine melanoma (B16F10), human colon carcinoma (HT29), human breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), human hepatocellular liver carcinoma (HepG2) and human glioblastoma (MO59J, U343 and U251). The antiproliferative activity was evaluated using XTT assay and results were expressed as IC50. The most pronounced antiproliferative activity was observed for SM, with IC50 values ranging from 4.58 to 18.23 μg/mL. The lowest IC50 values were observed against HepG2, being 9.60 μg/mL for SL, 4.58 μg/mL for SM and 6.01 μg/mL for SS. Thus, SL, SM and SS demonstrated antiproliferative activity against the tumor cell lines tested, and were most effective against the HepG2 cell line.

Treatment of leishmaniasis in the Oyapock basin (French Guiana): A K.A.P. survey and analysis of the evolution of phytotherapy knowledge amongst Wayãpi Indians

ETHNOPHARMACOLOGICAL RELEVANCE

Cutaneous leishmaniasis is a neglected disease with a high incidence in French Guiana, mainly in the middle and upper Oyapock basin, where Amerindian and some Brazilian people live. The main goals of this work were (i) to assess the knowledge about leishmaniasis in the different populations of the middle and upper Oyapock basin, (ii) to study the therapeutic strategies adopted by people affected by leishmaniasis and (iii) to document the use of phytotherapeutic remedies for leishmaniasis. Knowledge, attitudes and practices (K.A.P.) related to this disease and its treatments have been studied according to cultural group and geographical settlement. Within the Wayãpi group, the evolution of the knowledge of phytoremedies over the last 20 years has been characterised by literature-based comparisons.

MATERIALS AND METHODS

A total of 144 questionnaires were administered in all the villages of the upper Oyapock and Camopi basins. Correspondence analyses were used for multivariate analysis. Plant species were identified at the Cayenne Herbarium (CAY).

RESULTS

The biomedical concept of leishmaniasis correlates well with the Teko and Wayãpi concepts of kalasapa and kalasapau. Although the vector of this disease was not correctly identified, the most commonly cited aetiology (74.5%) was vector-borne, and related epidemiological schemes correlate well with the one encountered in French Guiana. Theoretically and practically, health centres were the most commonly used resource for diagnostic in instances of leishmaniasis infection (65.9%), independently of the patient's cultural group, along with the use of pharmaceutical drugs (85.3%). Pharmaceuticals were commonly utilised despite the frequent (51.5%) use of phytotherapeutic remedies, alone or in combination with drugs. The most cited medicinal plant species for the treatment of leishmaniasis included Eleutherine bulbosa (Mill.) Urb. (Iridaceae, cited 14 times), Euterpe oleracea Mart. (Arecaceae, 9), Cecropia obtusa Trecul (Cecropiaceae, 8), Jatropha curcas L. (Euphorbiaceae, 7), Ceiba pentandra (L.) Gaertn. (Bombacaceae, 6) and Carica papaya L. (Caricaceae, 6). Multiple correspondence analyses demonstrated that the species used in leishmaniasis remedies are more prone to vary by the user's place of residence than by their cultural origin, which indicates that exchange of knowledge about leishmaniasis remedies has occurred across different cultural groups. Literature-based comparisons between the remedies for leishmaniasis used by the Wayãpi during the 1980s showed a striking evolution, both in terms of diversity of species and number of plants used. The large number of species shared with other Guianese groups argues for intercultural exchange and may explain the majority (57.1%) of the newly used species highlighted in our study.

CONCLUSIONS

Leishmaniasis is a well-known disease in the studied area. Phytotherapeutic treatments are still in use, although they are not the main source of remedies, and should undergo pharmacological studies to evaluate their potential therapeutic value.

Sodium metabisulfite-induced polymerization of sickle cell hemoglobin incubated in the extracts of three medicinal plants (Anacardium occidentale, Psidium guajava, and Terminalia catappa)

Background:

The exploitation and utilization of vast varieties of herbal extracts may serve as alternative measures to deter aggregation of deoxygenated sickle cell hemoglobin (deoxyHbS) molecules.

Objective:

The present in vitro study ascertained the capacity of three medicinal plants, namely, Anacardium occidentale, Psidium guajava, and Terminalia catappa, to alter polymerization of HbS.

Materials and Methods:

Spectrophotometric method was used to monitor the level of polymerization of hemolysate HbS molecules treated with sodium metabisulfite (Na₂ S₂ O₅) at a regular interval of 30 s for a period of 180 s in the presence of separate aqueous extracts of A. occidentale, P. guajava, and T. catappa. At time intervals of 30 s, the level of polymerization was expressed as percentage of absorbance relative to the control sample at the 180th s.

Results:

Although extracts of the three medicinal plants caused significant (P < 0.05) reduction in polymerization of deoxyHbS molecules, the corresponding capacity in this regard diminished with increase in incubation time. Aqueous extract of P. guajava exhibited the highest capacity to reduced polymerization of deoxyHbS molecules. Whereas at t > 60 s, extract concentration of 400 mg% of A. occidentale activated polymerization of deoxyHbS molecules by 6.23±1.34, 14.53±1.67, 21.15±1.89, and 24.42±1.09%, 800 mg% of T. catappa at t > 30 s gave values of 2.50±1.93, 5.09±1.96, 10.00±0.99, 15.38±1.33, and 17.31±0.97%.

Conclusion:

The capacity of the three medicinal plants to interfere with polymerization of deoxyHbS molecules depended on the duration of incubation and concentration of the extracts.

Comparative Chemical, Cytotoxicity and Antileishmanial Properties of Essential Oils from Chenopodium ambrosioides

In countries where leishmaniasis is endemic, there are not very many treatment alternatives and most options have problems associated with their use. Plants and their natural products constitute good sources of interesting lead compounds that could be potentially active against Leishmania. Chenopodium ambrosioides is a plant that is widely used in popular medicine and its antiparasitic effects have been documented, including the antileishmanial potentialities of Chenopodium oil. The objective of this study was to determine the chemical composition, in-vitro cytotoxicity and antileishmanial activity of essential oils extracted from C. ambrosioides, which received different treatments prior to extraction. The chemical characterization by GC-MS of the three essential oil samples showed similar composition and the major components were α-terpinene (17.0-20.7%), p-cymene (20.2-21.1%) and ascaridole (30.5-47.1%). The essential oils exhibited similar antileishmanial activities against intracellular amastigote form, with IC50 values between 4.7 and 12.4 μg/mL. However, a lower cytotoxicity was displayed by the essential oil extracted from fresh green vegetable material, which was statistically different ( P < 0.05) from the other samples. This study demonstrated that the prior treatment of plant material did not interfere with the antiparasitic activity of essential oils from C. ambrosioides but did change their cytotoxicity, which should be taken into account in further studies.

Evaluation of the subchronic toxicity of oral treatment with Chenopodium ambrosioides in mice

AIM OF THE STUDY

The leaves of Chenopodium ambrosioides L. (Chenopodiaceae) have been used by native people to treat many diseases. Recently, we showed that the treatment with small dose (5mg/kg) of hydroalcoholic extract (HE) from Chenopodium ambrosioides' leaves has immunestimulatory effects. The aim of this study was to investigate the subchronic toxicity of the oral treatment with this HE in preclinical assays.

MATERIAL AND METHODS

Swiss mice were divided into 4 groups (n=10/group). They received the HE daily at the doses of 5, 50 and 500 mg/kg by gavage during 15 days. The control group received only water. They were observed each hour for 24h and each day for 15 days, when the blood was collected. The serum was used to perform the biochemical analysis. The mice were then killed and the vital and lymphoid organs were collected and evaluated.

RESULTS

There was neither death nor alterations in the body weight in the HE-treated groups, but there were alterations in the weight of some organs. There was an increase in the lymph node cells number in the highest two doses. The number of cells in the bone marrow was high in the HE-treated groups, but the number of peritoneal cells was smaller in the HE-treated groups when compared to the control. There was no alteration in the AST, but there was a reduction in the albumin levels in the HE500 group and in the triglycerides and VLDL in the highest doses.

CONCLUSION

The subchronic treatment with HE induced punctual alterations in the groups treated with the highest doses. However, the HE treatment was not lethal and did not induce toxic alterations using the therapeutic dose, suggesting that it is safe to use this product in the adequate dose.

Ethnomedicine and ethnobotany of fright, a Caribbean culture-bound psychiatric syndrome

BACKGROUND

"Fright" is an English-speaking Caribbean idiom for an illness, or ethnomedical syndrome, of persistent distress. A parallel ethnopsychiatric idiom exists in the French Antilles as sésisma. Fright is distinct from susto among Hispanics, though both develop in the wake of traumatic events. West Indian ethnophysiology (ethnoanatomy) theorizes that an overload of stressful emotions (fear, panic, anguish or worry) causes a cold humoral state in which blood coagulates causing prolonged distress and increased risks of other humorally cold illnesses.

METHODS

Qualitative data on local explanatory models and treatment of fright were collected using participant-observation, informal key informant interviews and a village health survey. Ethnobotanical and epidemiological data come from freelist (or "free-list") tasks, analyzed for salience, with nearly all adults (N = 112) of an eastern village in Dominica, and a village survey on medicinal plant recognition and use (N = 106).

RESULTS

Along with prayer and exercise, three herbs are salient fright treatments: Gossypium barbadense L., Lippia micromera Schauer, and, Plectranthus [Coleus] amboinicus [Loureiro] Sprengel. The survey indicated that 27% of village adults had medicated themselves for fright. Logistic regression of fright suffering onto demographic variables of age, education, gender, parental status and wealth measured in consumer goods found age to be the only significant predictor of having had fright. The probability of having (and medicating for) fright thus increases with every year.

CONCLUSIONS

While sufferers are often uncomfortable recalling personal fright experiences, reporting use of medicinal plants is less problematic. Inquiry on fright medical ethnobotany (or phytotherapies) serves as a proxy measurement for fright occurrence. Cross-cultural and ethnopharmacology literature on the medicinal plants suggests probable efficacy in accord with Dominican ethnomedical notions of fright. Further, the cultural salience and beliefs about these medicines may give these medications extra psychoneuroimmune (i.e. mind-body) benefits, or placebo-like effects, for this stress-related folk illness.