Antileishmanial Activity Of Extracts Research Articles

Antileishmanial activity of extracts from Libidibia ferrea: development of in vitro and in vivo tests

ABSTRACT Treatment of cutaneous leishmaniasis (CL) is difficult due to the scarce number of drugs able to eliminate completely the intracellular form of the parasite. In the present study, the aim was to evaluate: i) phytochemical properties of extracts from Libidibia ferrea; ii) antileishmanial activity of extracts from L. ferrea against promastigotes and amastigotes of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) guyanensis; iii) the effects of topical treatment using hydrogel containing active extract of L. ferrea on golden hamsters infected with L. (L.) amazonensis. Extracts from leaves, branches and fruits of L. ferrea were obtained with hexane and methanol and were tested by in vitro assays in promastigotes and murine macrophages J774 experimentally infected with amastigotes of Leishmania. Groups of hamsters with CL received topical treatment with a formulation of extract (10%) hydrogels, 50 mg.day-1 for 40 days. In vitro activity of FrMeOH (methanolic extract from fruits without seeds) resulted in significant reduction of viable promastigotes of L. (L.) amazonensis (IC50 of 15.4 µg.mL-1) and demonstrated inhibition potential of amastigote forms of L. (L.) amazonensis and L. (V.) guyanensis and low cytotoxicity in macrophages. The overall data of topical treatment with extract hydrogels (GelFrMeOH) showed that lesion sizes were significantly reduced (42.78%), with low parasite burden by RT-qPCR and culture analysis by microscopy examination, and with histopathological findings such as lower inflammatory cell infiltration 40 days after treatment. Chemical analysis demonstrated FrMeOH contains high levels of phenolic compounds. The results indicate a possible alternative therapy for CL using phytotherapics.

Anti-leishmanial activity of extracts from a brown seaweed Bifurcaria bifurcata the Atlantic coast of Morocco

Au cours de ce travail nous avons realise des activites anti-leishmaniennes sur les extraits hexanique, ethere, chloroformique et methanolique de l’algue marine Bifurcaria bifurcata, les extraits sont obtenus par un systeme d’extraction au soxhlet, les rendements des extraits representent environ de 1% a 8% du poids de l’algue brute. L’activite anti-leshmanienne a ete realisee in vitro par la methode colorimetrique MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) sur des parasites de type Leishmania infantum. Parallelement, un test a ete realise de cytotoxicite Brine Shrimp sur les larves d’Artemia salina pour mesurer le pouvoir de toxicite des extraits etudies. L’ensemble des resultats obtenus montrent que les produits extraits de l’algue Bifurcaria bifurcata presentent une activite anti-leishamnienne remarquable, d’ou les valeurs de CI50 les concentrations d’inhibition de 50% des extraits respectivement varient de 46,83 µg/mL a 3,83 µg/mL, ainsi les doses letales mediane de test de cytotoxicite sont inferieures a 40,46 µg/mL. Ces resultats pouvant faire l’objet de l’application desproduits obtenus de l’algue Bifurcaria bifurcata dans le traitement des Leishmanioses.

Antileishmanial activity of extracts from Calophyllum brasiliense Cambess leaves obtained by conventional and supercritical extraction

Antileishmanial activity of extracts from Calophyllum brasiliense Cambess leaves obtained by conventional and supercritical extraction

In vitro anti-leishmanial activity of methanolic extracts of Calendula officinalis flowers, Datura stramonium seeds, and Salvia officinalis leaves

AimThe anti-leishmanial activity of methanolic extracts of Calendula officinalis flowers, Datura stramonium seeds, and Salvia officinalis leaves against extracellular (promastigote) and intracellular (amastigote) forms of Leishmania major were evaluated in this study. MethodIn the first stage, promastigote forms of L. major, were treated with different doses of the plant extracts in a 96-well tissue-culture microplate and IC50 values for each extract were measured with colorimetric MTT assay. In the second stage, macrophage cells were infected with L. major promastigotes. Infected macrophages were treated with plant extracts. Then the macrophages were stained with Gimsa and the number of infected macrophages and amastigotes were counted with a light microscope. ResultsThe results indicated that the plant extracts inhibited the growth of promastigotes and amastigotes of L. major. Inhibitory concentrations (IC50) for promastigote assay were 108.19, 155.15, and 184.32 μg7middot;mL−1 for C. officinalis flowers, D. stramonium seeds and S. officinalis, respectively. The extracts also reduced the number of amastigotes in macrophage cells from 264 for control group to 88, 97, and 102 for test groups. Although the anti-leishmanial activity of the extracts were not comparable with the standard drug, miltefosine; but they showed significant efficiency in reducing the number of amastigotes in macrophages, in comparison with the control group (P < 0.001). These plant extracts had lower toxicity compared with miltefosine. ConclusionThis study demonstrates the potential efficacy of the methanolic extracts of C. officinalis flowers, D. stramonium seeds, and S. officinalis leaves to control of cutaneous leishmaniasis.

Antileishmanial compounds from Moringa oleifera Lam.

The antileishmanial activity of extracts and phytoconstituents of Moringa oleifera Lam. was investigated in vitro against promastigotes of Leishmania donavani. The 70% ethanolic extract of roots and the methanolic extract of leaves showed moderate inhibitory activity with IC50 values of 83.0 microg/ml and 47.5 microg/ml, respectively. Antileishmanial activity of the methanolic extract of leaves increased upon fractionation, as its ethyl acetate fraction was found to be more active with an IC50 value of 27.5 microg/ml. The most active antileishmanial compound niazinin, a thiocarbamate glycoside isolated from this fraction, showed an IC50 value of 5.25 microM. Results presented in this study indicate that extracts from M. oleifera may be developed as an adjuvant therapy for the treatment of leishmaniasis.

Antileishmanial and cytotoxic activities of three plants used in colombian folk medicine

As part of our research on medicinal plants traditionally used in folk medicine in Casanare (Colombia), some important species were selected for further studies through phytochemical exploration. In this study, we investigate the phytochemical profile, antileishmanial and cytotoxic activities of three selected plants (Bowdichia virgilioides, Jacaranda obtusifolia, and Hymenaea courbaril). These plants are commonly used in the above-mentioned region to treat different infectious diseases. Leaves from test plants were collected in Casanare, Colombia, dried, grounded and macerated with ethanol. The chemical profile was determined by UFLC-DAD analysis and by measuring total phenolic (TP) and total flavonoid (TF) contents. They were also tested against promastigotes of Leishmania panamensis, J774 murine macrophages and THP-1 monocytes in order to examine a preliminary extracts' ability and security in a screening platform. The TP and TF contents (> 30 mg gallic acid equiv/g DE and > 3 mg quercetin equiv/g DE, respectively) were found to be reasonable. Chemical characterization of the ethanol extracts was achieved by UFLC-DAD employing a validated method for profiling herbal extracts using standards. All extracts were found to be enriched in flavonoid-related metabolites. Antileishmanial activity of extracts exhibited relatively high EC50 values (20 – 100 µg/mL). The extract from Hymenaea courbaril was the most active (EC50= 20.1 µg/mL). Additionally, a low cytotoxiciy against J774 and THP-1 was determined for all extracts (IC50 > 600 µg/mL, selectivity indexes (SI) > 8). Although the activity against promastigotes is quite low, and tests with the more relevant amastigotes must follow, these results might be related to the traditional use of these plants to treat infections. Therefore, the evaluation of test extracts against amastigotes and a bioguided fractionation to obtain bioactive compounds is currently in progress.

The cytotoxic and antileishmanial activity of extracts and fractions of leaves and fruits of Azadirachta indica (A Juss.)

The leishmaniases are severe parasitic diseases that occur worldwide, caused by protozoa of the genus Leishmania. Studies with medicinal plants can lead to a range of possibilities for treating and improving the patients' quality of life. Research on Azadirachta indica fractions and extracts has shown that they have excellent anti-leishmanial activity based on bioactivity-guided fractionation of ethanolic extracts of leaves and seeds and in vitro activity against promastigotes. In this research the most efficient extracts and fractions were selected for tests on intracellular amastigotes of Leishmania amazonensis. The ethanolic extract of the leaves and dichloromethane and chloroform fractions had IC(50) values of 38, 3.9 and 1.2 μg/mL for promastigotes and 9.8, 1.1 and 0.6 μg/mL for amastigotes, respectively, at 72 hours. For the ethanolic extract and dichloromethane fraction from nut tegument, the IC(50) was 2.7 and 2.1 μg/mL for promastigotes and 0.4 and 0.6 μg/mL for amastigotes. The cytotoxicity of the fractions presented selectivity that was between 8 to 32 times more toxic to promastigotes and 15 to 72 times to amastigotes than to macrophages. The extracts and fractions from leaves and fruits were more effective against amastigotes, and the fractionation increased activity against both promastigotes and amastigotes, enabling us to obtain potentially active fractions with low toxicity.

In Vitro Atileishmanial and Cytotoxic Activities of Annona mucosa (Annonaceae)

The antileishmanial activity of extracts from the leaves and seeds of Annona mucosa, and of the oxoaporphine alkaloid liriodenine isolated from the dichloromethane extract of the leaves, were evaluated in vitro against promastigote forms of three Leishmania species and against intracellular amastigote forms of L. amazonensis. Cytotoxic activity was evaluated against peritoneal macrophages of mice. The dichloromethane extract from the leaves was the most active against Leishmania spp., showing IC50 values lower than 30 μg.mL . Liriodenine was the most cytotoxic against peritoneal macrophages. Hexane extracts of seeds showed the highest selectivity index against Leishmania spp. (SI = 5.93 to 1.54). All samples were active against intracellular amastigote forms, after 96 h inhibiting more than 70% of amastigote replication in infected macrophages. Phytochemical investigation of the dichloromethane extract from the leaves of A. mucosa led to the isolation of the oxoaporphine alkaloids atherospermidine (1) and liriodenine (2), identified on the basis of their spectroscopic data, mainly 1D/2D NMR, and comparison with literature data.