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White jute (Corchorus capsularis L.) leaf extract has potent leishmanicidal activity against Leishmania donovani

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Abstract

In pursuit of effective, safe and affordable antileishmanial drugs, the current study was designed to explore Corchorus capsularis L. leaf extract (CCEx) as an effective leishmanicidal substitute against Leishmania donovani. The leaf extract displays potent antileishmanial activity against L. donovani promastigotes with an IC 50 value of 79.00 ± 0.3 μg/ml. CCEx also significantly induces intracellular reactive oxygen species (ROS) with a concomitant decrease in the level of non-protein thiols in virulent parasites. Additionally, CCEx treatment induces substantial morphological alterations in parasites. Moreover, reagent-based phytochemical analysis of the extract revealed the presence of various phytochemical constituents. Further study is underway to identify the bioactive component(s) or fraction(s) of CCEx through bioassay-guided fractionation.

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... The first two ranked compounds, corosolic acid (1) and jacoumaric acid (2) were more active than guajadial B (5) and medicagenic acid (6), with an IC50 of 1.32 ± 0.59 µg/mL for jacoumaric acid and 1.01 ± 0.06 µg/mL for corosolic acid ( Table 2). Since most antileishmanial drugs act by the production of reactive oxygen species (ROS) that lead to the death of parasites [23,24], we measured the production of ROS induced by jacoumaric acid and corosolic acid at the IC50 (1.32 µg/mL and 1.06 µg/mL, respectively) and IC90 (1.90 µg/mL and 1.43 µg/mL, respectively) using H2DCFDA (2′,7′-dichlorodihydrofluorescein diacetate). The corresponding graph presented in Figure 4A clearly demonstrates that jacoumaric acid and corosolic Table 1 for details). ...
... The first two ranked compounds, corosolic acid (1) and jacoumaric acid (2) were more active than guajadial B (5) and medicagenic acid (6), with an IC 50 of 1.32 ± 0.59 µg/mL for jacoumaric acid and 1.01 ± 0.06 µg/mL for corosolic acid ( Table 2). Since most antileishmanial drugs act by the production of reactive oxygen species (ROS) that lead to the death of parasites [23,24], we measured the production of ROS induced by jacoumaric acid and corosolic acid at the IC 50 (1.32 µg/mL and 1.06 µg/mL, respectively) and IC 90 (1.90 µg/mL and 1.43 µg/mL, respectively) using H 2 DCFDA (2 ,7 -dichlorodihydrofluorescein diacetate). ...
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... In 2019 P.K. Pramanik, et al conducted a research on Corchorus capsularis L. leaf extract (CCEx) as a replacement leishmanicide for Leishmania donovani. The widespread plant Corchorus capsularis L., also known as white jute, has a variety of therapeutic benefits [41]. The leaves of C. capsularis L. have strong antimicrobial, anti-inflammatory and antinociceptive effects [65] [66]. ...
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... [84] Antileishmanial activity C. capsularis Leaf Chloroform Showed potent antileishmanial activity against L. donovani promastigotes with an IC50 value of 79 μg/mL and exhibited very specific apoptotic features by targeting LdTryR. [80,167] Antibacterial activity C. capsularis C. olitorius Leaf Lipophilic extracts ...
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... Antipromastigote activity and cytotoxicity assay of β-sitosterol CCL and commercial β-sitosterol. To check the inhibitory effect of commercial β-sitosterol on the growth of L. donovani promastigotes, an MTT assay was performed as described previously 9 . Promastigotes (1 × 10 7 /well) were treated individually with β-sitosterol CCL and commercial β-sitosterol (Abcam, USA) (0-200 µg/ml) for 48 h. ...
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Leishmaniasis is a major public health problem, and the alarming spread of parasite resistance underlines the importance of discovering new therapeutic products. The present study aims to investigate the in vitro leishmanicidal activity of an Agaricus blazei Murill mushroom extract as compared to different Leishmania species and stages. The water extract proved to be effective against promastigote and amastigote-like stages of Leishmania amazonensis, L. chagasi, and L. major, with IC(50) (50% inhibitory concentration) values of 67.5, 65.8, and 56.8 μg/mL for promastigotes, and 115.4, 112.3, and 108.4 μg/mL for amastigotes-like respectively. The infectivity of the three Leishmania species before and after treatment with the water extract was analyzed, and it could be observed that 82%, 57%, and 73% of the macrophages were infected with L. amazonensis, L. major, and L. chagasi, respectively. However, when parasites were pre-incubated with the water extract, and later used to infect macrophages, they were able to infect only 12.7%, 24.5%, and 19.7% of the phagocytic cells for L. amazonensis, L. chagasi, and L. major, respectively. In other experiments, macrophages were infected with L. amazonensis, L. chagasi, or L. major, and later treated with the aforementioned extract, presented reductions of 84.4%, 79.6%, and 85.3% in the parasite burden after treatment. A confocal microscopy revealed the loss of the viability of the parasites within the infected macrophages after treatment with the water extract. The applied extract presented a low cytotoxicity in murine macrophages and a null hemolytic activity in type O(+) human red blood cells. No nitric oxide (NO) production, nor inducible nitric oxide syntase expression, could be observed in macrophages after stimulation with the water extract, suggesting that biological activity may be due to direct mechanisms other than macrophage activation by means of NO production. In conclusion, the results demonstrate that the A. blazei Murill water extract can potentially be used as a therapeutic alternative on its own, or in association with other drugs, to treat Visceral and Cutaneous Leishmaniasis.
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There is growing evidence that metalloid-induced cell death in protozoan parasites is due to oxidative injury; however, the biochemical changes related to this event are not fully understood. Leishmania spp. demonstrated cross-resistance to two related metalloids, arsenic and antimony, and both metalloids induced cell death accompanied by cell shrinkage and DNA fragmentation that was preceded by an increase in reactive oxygen species. Both drugs caused mitochondrial dysfunction in terms of loss of membrane potential and a drop in ATP levels. Arsenic treatment resulted in an elevation of intracellular Ca2+ levels that did not occur with antimony exposure. Cellular glutathione level was reduced after antimony treatment but arsenic did not affect glutathione. Inhibition of Ca2+ influx during arsenic treatment reduced cell death, whereas supplementation of glutathione during antimony treatment rescued cell loss. Under iron-depleted conditions, the cytotoxic effects of arsenic and antimony did not occur and cell survival increased; in contrast, the presence of excess iron resulted in higher cell death. Therefore, this study provides a new possibility that iron can potentiate parasite death induced by metalloids like arsenic and antimony. In addition, an important observation is that the two similar metalloids produce toxicity by very different mechanisms.
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Leishmaniases remain a major public health problem today despite the vast amount of research conducted on Leishmania pathogens. The biological model is genetically and ecologically complex. This paper explores the advances in Leishmania genetics and reviews population structure, taxonomy, epidemiology and pathogenicity. Current knowledge of Leishmania genetics is placed in the context of natural populations. Various studies have described a clonal structure for Leishmania but recombination, pseudo-recombination and other genetic processes have also been reported. The impact of these different models on epidemiology and the medical aspects of leishmaniases is considered from an evolutionary point of view. The role of these parasites in the expression of pathogenicity in humans is also explored. It is important to ascertain whether genetic variability of the parasites is related to the different clinical expressions of leishmaniasis. The review aims to put current knowledge of Leishmania and the leishmaniases in perspective and to underline priority questions which 'leishmaniacs' must answer in various domains: epidemiology, population genetics, taxonomy and pathogenicity. It concludes by presenting a number of feasible ways of responding to these questions.