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1.
Medicine (Baltimore) ; 103(18): e38039, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38701291

ABSTRACT

As a result of increasing drug resistance, crossover resistance development, prolonged therapy, and the absence of different agents with innovative methods for implementation, the efficacy of recent antileishmanial medications is severely declining. So, it is vital to look for other medications from botanical remedies that have antileishmanial activity. The latex of Euphorbia abyssinica (E abyssinica) and the leaves of Clematis simensis fresen (C simensis) were macerated in methanol (80%). In vitro antileishmanial activity of the preparation was tried on promastigotes of Leishmania aethiopica (L aethiopica) and Leishmania donovani (L donovani) using resazurin assay, and fluorescence intensity was measured. One percent of dimethyl sulfoxide (DMSO) and media as negative control and amphotericin B as positive control were used. Additionally, hemolytic & phytochemical tests of the preparation were done. The mean and standard errors of each extract were evaluated and interpreted for statistical significance using one-way analysis of variance. From sigmoidal dose-response curves of % inhibition, half maximal inhibitory concentration (IC50) values were determined by GraphPad Prism and Microsoft Excel; outcomes were presented as mean ±â€…standard error of mean of triplicate trials. P < .05 was statistical significance. The phytochemical screening of C simensis and E abyssinica confirmed the existence of steroids, phenols, tannins, saponins, alkaloids, terpenoids, flavonoids and glycosides. C simensis possesses antileishmanial activity with IC50 outcomes of 46.12 ±â€…0.03 and 8.18 ±â€…0.10 µg/mL on the promastigotes of L aethiopica and L donovani, respectively. However, E abyssinica showed stronger activity with IC50 outcomes of 16.07 ±â€…0.05 µg/mL and 4.82 ±â€…0.07 µg/mL on L aethiopica and L donovani, respectively. C simensis and E abyssinica have a less hemolytic effect on human red blood cells at low concentrations. The outcomes from this investigation demonstrated that the preparation of C simensis and E abyssinica indicated significant antileishmanial activity. Therefore, further in vivo assessment of antileishmanial, cytotoxicity activity and quantitative identification of secondary metabolites are highly recommended.


Subject(s)
Antiprotozoal Agents , Euphorbia , Latex , Plant Extracts , Plant Leaves , Plant Extracts/pharmacology , Euphorbia/chemistry , Latex/pharmacology , Latex/chemistry , Antiprotozoal Agents/pharmacology , Plant Leaves/chemistry , Humans , Leishmania donovani/drug effects , Inhibitory Concentration 50 , Leishmania/drug effects , Methanol , Solvents , Hemolysis/drug effects
2.
Parasite Immunol ; 46(5): e13037, 2024 May.
Article in English | MEDLINE | ID: mdl-38720446

ABSTRACT

The treatment for visceral leishmaniasis (VL) causes toxicity in patients, entails high cost and/or leads to the emergence of resistant strains. No human vaccine exists, and diagnosis presents problems related to the sensitivity or specificity of the tests. Here, we tested two phage clones, B1 and D11, which were shown to be protective against Leishmania infantum infection in a murine model as immunotherapeutics to treat mice infected with this parasite species. The phages were used alone or with amphotericin B (AmpB), while other mice received saline, AmpB, a wild-type phage (WTP) or WTP/AmpB. Results showed that the B1/AmpB and D11/AmpB combinations induced polarised Th1-type cellular and humoral responses, which were primed by high levels of parasite-specific IFN-γ, IL-12, TNF-α, nitrite and IgG2a antibodies, which reflected in significant reductions in the parasite load in distinct organs of the animals when analyses were performed 1 and 30 days after the treatments. Reduced organic toxicity was also found in these animals, as compared with the controls. In conclusion, preliminary data suggest the potential of the B1/AmpB and D11/AmpB combinations as immunotherapeutics against L. infantum infection.


Subject(s)
Amphotericin B , Antibodies, Protozoan , Immunotherapy , Leishmania infantum , Leishmaniasis, Visceral , Mice, Inbred BALB C , Leishmaniasis, Visceral/immunology , Leishmaniasis, Visceral/drug therapy , Animals , Amphotericin B/therapeutic use , Amphotericin B/administration & dosage , Antibodies, Protozoan/blood , Leishmania infantum/immunology , Leishmania infantum/drug effects , Mice , Immunotherapy/methods , Female , Antiprotozoal Agents/therapeutic use , Antiprotozoal Agents/administration & dosage , Immunoglobulin G/blood , Parasite Load , Disease Models, Animal , Cell Surface Display Techniques , Cytokines/metabolism , Th1 Cells/immunology
3.
Sci Rep ; 14(1): 10073, 2024 05 02.
Article in English | MEDLINE | ID: mdl-38698123

ABSTRACT

Cutaneous leishmaniasis is the most prevalent form of leishmaniasis worldwide. Although various anti-leishmanial regimens have been considered, due to the lack of efficacy or occurrence of adverse reactions, design and development of novel topical delivery systems would be essential. This study aimed to prepare artemether (ART)-loaded niosomes and evaluate their anti-leishmanial effects against Leishmania major. ART-loaded niosomes were prepared through the thin-film hydration technique and characterized in terms of particle size, zeta potential, morphology, differential scanning calorimetry, drug loading, and drug release. Furthermore, anti-leishmanial effect of the preparation was assessed in vitro and in vivo. The prepared ART-loaded niosomes were spherical with an average diameter of about 100 and 300 nm with high encapsulation efficiencies of > 99%. The results of in vitro cytotoxicity revealed that ART-loaded niosomes had significantly higher anti-leishmanial activity, lower general toxicity, and higher selectivity index (SI). Half-maximal inhibitory concentration (IC50) values of ART, ART-loaded niosomes, and liposomal amphotericin B were 39.09, 15.12, and 20 µg/mL, respectively. Also, according to the in vivo study results, ART-loaded niosomes with an average size of 300 nm showed the highest anti-leishmanial effects in animal studies. ART-loaded niosomes would be promising topical drug delivery system for the management of cutaneous leishmaniasis.


Subject(s)
Artemether , Leishmania major , Leishmaniasis, Cutaneous , Liposomes , Liposomes/chemistry , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Cutaneous/parasitology , Artemether/chemistry , Leishmania major/drug effects , Animals , Mice , Particle Size , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/administration & dosage , Antiprotozoal Agents/chemistry , Mice, Inbred BALB C , Drug Liberation , Humans
4.
Chem Biol Drug Des ; 103(5): e14535, 2024 May.
Article in English | MEDLINE | ID: mdl-38772877

ABSTRACT

Despite efforts, available alternatives for the treatment of leishmaniasis are still scarce. In this work we tested a class of 15 quinolinylhydrazone analogues and presented data that support the use of the most active compound in cutaneous leishmaniasis caused by Leishmania amazonensis. In general, the compounds showed activity at low concentrations for both parasitic forms (5.33-37.04 µM to promastigotes, and 14.31-61.98 µM to amastigotes). In addition, the best compound (MHZ15) is highly selective for the parasite. Biochemical studies indicate that the treatment of promastigotes with MHZ15 leads the loss of mitochondrial potential and increase in ROS levels as the primary effects, which triggers accumulation of lipid droplets, loss of plasma membrane integrity and apoptosis hallmarks, including DNA fragmentation and phosphatidylserine exposure. These effects were similar in the intracellular form of the parasite. However, in this parasitic form there is no change in plasma membrane integrity in the observed treatment time, which can be attributed to metabolic differences and the resilience of the amastigote. Also, ultrastructural changes such as vacuolization suggesting autophagy were observed. The in vivo effectiveness of MHZ15 in the experimental model of cutaneous leishmaniasis was carried out in mice of the BALB/c strain infected with L. amazonensis. The treatment by intralesional route showed that MHZ15 acted with great efficiency with significantly reduction in the parasite load in the injured paws and draining lymph nodes, without clinical signs of distress or compromise of animal welfare. In vivo toxicity was also evaluated and null alterations in the levels of hepatic enzymes aspartate aminotransferase, and alanine aminotransferase was observed. The data presented herein demonstrates that MHZ15 exhibits a range of favorable characteristics conducive to the development of an antileishmanial agent.


Subject(s)
Apoptosis , Hydrazones , Leishmaniasis, Cutaneous , Mice, Inbred BALB C , Mitochondria , Animals , Apoptosis/drug effects , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Hydrazones/pharmacology , Hydrazones/chemistry , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Cutaneous/parasitology , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/therapeutic use , Leishmania/drug effects , Reactive Oxygen Species/metabolism , Female , Leishmania mexicana/drug effects , Membrane Potential, Mitochondrial/drug effects
5.
Parasitol Res ; 123(5): 217, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38772951

ABSTRACT

Toxoplasmosis poses a global health threat, ranging from asymptomatic cases to severe, potentially fatal manifestations, especially in immunocompromised individuals and congenital transmission. Prior research suggests that oregano essential oil (OEO) exhibits diverse biological effects, including antiparasitic activity against Toxoplasma gondii. Given concerns about current treatments, exploring new compounds is important. This study was to assess the toxicity of OEO on BeWo cells and T. gondii tachyzoites, as well as to evaluate its effectiveness in in vitro infection models and determine its direct action on free tachyzoites. OEO toxicity on BeWo cells and T. gondii tachyzoites was assessed by MTT and trypan blue methods, determining cytotoxic concentration (CC50), inhibitory concentration (IC50), and selectivity index (SI). Infection and proliferation indices were analyzed. Direct assessments of the parasite included reactive oxygen species (ROS) levels, mitochondrial membrane potential, necrosis, and apoptosis, as well as electron microscopy. Oregano oil exhibited low cytotoxicity on BeWo cells (CC50: 114.8 µg/mL ± 0.01) and reduced parasite viability (IC50 12.5 ± 0.06 µg/mL), demonstrating 9.18 times greater selectivity for parasites than BeWo cells. OEO treatment significantly decreased intracellular proliferation in infected cells by 84% after 24 h with 50 µg/mL. Mechanistic investigations revealed increased ROS levels, mitochondrial depolarization, and lipid droplet formation, linked to autophagy induction and plasma membrane permeabilization. These alterations, observed through electron microscopy, suggested a necrotic process confirmed by propidium iodide labeling. OEO treatment demonstrated anti-T. gondii action through cellular and metabolic change while maintaining low toxicity to trophoblastic cells.


Subject(s)
Autophagy , Oils, Volatile , Origanum , Reactive Oxygen Species , Toxoplasma , Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Toxoplasma/drug effects , Toxoplasma/growth & development , Origanum/chemistry , Humans , Autophagy/drug effects , Reactive Oxygen Species/metabolism , Cell Line , Antiprotozoal Agents/pharmacology , Inhibitory Concentration 50 , Necrosis/drug therapy , Cell Survival/drug effects , Apoptosis/drug effects , Membrane Potential, Mitochondrial/drug effects
6.
Sci Rep ; 14(1): 11575, 2024 05 21.
Article in English | MEDLINE | ID: mdl-38773273

ABSTRACT

Leishmaniasis is a disease caused by a protozoan of the genus Leishmania, affecting millions of people, mainly in tropical countries, due to poor social conditions and low economic development. First-line chemotherapeutic agents involve highly toxic pentavalent antimonials, while treatment failure is mainly due to the emergence of drug-resistant strains. Leishmania arginase (ARG) enzyme is vital in pathogenicity and contributes to a higher infection rate, thus representing a potential drug target. This study helps in designing ARG inhibitors for the treatment of leishmaniasis. Py-CoMFA (3D-QSAR) models were constructed using 34 inhibitors from different chemical classes against ARG from L. (L.) amazonensis (LaARG). The 3D-QSAR predictions showed an excellent correlation between experimental and calculated pIC50 values. The molecular docking study identified the favorable hydrophobicity contribution of phenyl and cyclohexyl groups as substituents in the enzyme allosteric site. Molecular dynamics simulations of selected protein-ligand complexes were conducted to understand derivatives' interaction modes and affinity in both active and allosteric sites. Two cinnamide compounds, 7g and 7k, were identified, with similar structures to the reference 4h allosteric site inhibitor. These compounds can guide the development of more effective arginase inhibitors as potential antileishmanial drugs.


Subject(s)
Arginase , Enzyme Inhibitors , Leishmania , Molecular Docking Simulation , Molecular Dynamics Simulation , Arginase/antagonists & inhibitors , Arginase/chemistry , Arginase/metabolism , Leishmania/enzymology , Leishmania/drug effects , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Quantitative Structure-Activity Relationship , Protozoan Proteins/antagonists & inhibitors , Protozoan Proteins/chemistry , Protozoan Proteins/metabolism , Allosteric Site , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Catalytic Domain
7.
PLoS Negl Trop Dis ; 18(5): e0012156, 2024 May.
Article in English | MEDLINE | ID: mdl-38709850

ABSTRACT

The multifactorial basis of therapeutic response can obscure the relation between antimicrobial drug susceptibility and clinical outcome. To discern the relationship between parasite susceptibility to meglumine antimoniate (SbV) and therapeutic outcome of cutaneous leishmaniasis, risk factors for treatment failure were considered in evaluating this relationship in ninety-one cutaneous leishmaniasis patients and corresponding clinical strains of Leishmania (Viannia) panamensis. Parasite susceptibility to 32 µg SbV/mL (plasma Cmax) was evaluated in primary human macrophages, PBMCs, and U937 macrophages. Early parasitological response to treatment was determined in lesions of a subgroup of patients, and pathogenicity of Sb-resistant and sensitive clinical strains was compared in BALB/c mice. Parasite survival in cell models and patient lesions was determined by qRT-PCR of Leishmania 7SLRNA transcript. Parasite loads in BALB/c mice were quantified by limiting dilution analysis. The disparate Sb-susceptibility of parasite subpopulations distinguished by isoenzyme profiles (zymodemes) was manifest in all cell models. Notably, Sb-resistance defined by parasite survival, was most effectively discerned in U937 macrophages compared with primary human host cells, significantly higher among strains from patients who failed treatment than cured and, significantly associated with treatment failure. Each unit increase in transformed survival rate corresponded to a 10.6-fold rise in the odds of treatment failure. Furthermore, treatment failure was significantly associated with naturally Sb-resistant zymodeme 2.3 strains, which also produced larger lesions and parasite burdens in BALB/c mice than Sb-sensitive zymodeme 2.2 strains. The confounding effect of host risk factors for treatment failure in discerning this association was evidenced in comparing strains from patients with and without the defined risk factors for treatment failure. These results establish the association of natural resistance to meglumine antimoniate with treatment failure, the importance of host risk factors in evaluating drug susceptibility and treatment outcome, and the clinical and epidemiological relevance of natural Sb-resistance in L. (V.) panamensis subpopulations.


Subject(s)
Antiprotozoal Agents , Drug Resistance , Leishmaniasis, Cutaneous , Macrophages , Meglumine Antimoniate , Meglumine , Mice, Inbred BALB C , Organometallic Compounds , Treatment Failure , Animals , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Cutaneous/parasitology , Meglumine Antimoniate/therapeutic use , Meglumine Antimoniate/pharmacology , Humans , Antiprotozoal Agents/therapeutic use , Antiprotozoal Agents/pharmacology , Female , Meglumine/therapeutic use , Meglumine/pharmacology , Organometallic Compounds/therapeutic use , Organometallic Compounds/pharmacology , Mice , Macrophages/parasitology , Macrophages/drug effects , Macrophages/immunology , Male , Leishmania guyanensis/drug effects , Adult , Middle Aged , Young Adult , Parasite Load , Adolescent
8.
Molecules ; 29(9)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38731562

ABSTRACT

Leishmaniasis and Human African trypanosomiasis pose significant public health threats in resource-limited regions, accentuated by the drawbacks of the current antiprotozoal treatments and the lack of approved vaccines. Considering the demand for novel therapeutic drugs, a series of BODIPY derivatives with several functionalizations at the meso, 2 and/or 6 positions of the core were synthesized and characterized. The in vitro activity against Trypanosoma brucei and Leishmania major parasites was carried out alongside a human healthy cell line (MRC-5) to establish selectivity indices (SIs). Notably, the meso-substituted BODIPY, with 1-dimethylaminonaphthalene (1b) and anthracene moiety (1c), were the most active against L. major, displaying IC50 = 4.84 and 5.41 µM, with a 16 and 18-fold selectivity over MRC-5 cells, respectively. In contrast, the mono-formylated analogues 2b and 2c exhibited the highest toxicity (IC50 = 2.84 and 6.17 µM, respectively) and selectivity (SI = 24 and 11, respectively) against T. brucei. Further insights on the activity of these compounds were gathered from molecular docking studies. The results suggest that these BODIPYs act as competitive inhibitors targeting the NADPH/NADP+ linkage site of the pteridine reductase (PR) enzyme. Additionally, these findings unveil a range of quasi-degenerate binding complexes formed between the PRs and the investigated BODIPY derivatives. These results suggest a potential correlation between the anti-parasitic activity and the presence of multiple configurations that block the same site of the enzyme.


Subject(s)
Antiprotozoal Agents , Boron Compounds , Leishmania major , Molecular Docking Simulation , Trypanosoma brucei brucei , Boron Compounds/chemistry , Boron Compounds/pharmacology , Boron Compounds/chemical synthesis , Trypanosoma brucei brucei/drug effects , Humans , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/chemical synthesis , Leishmania major/drug effects , Drug Design , Structure-Activity Relationship , Cell Line , Molecular Structure , Trypanocidal Agents/pharmacology , Trypanocidal Agents/chemistry , Trypanocidal Agents/chemical synthesis , Oxidoreductases
9.
Int J Mol Sci ; 25(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38731916

ABSTRACT

Herein, we report a series of 1,3-diarylpyrazoles that are analogues of compound 26/HIT 8. We previously identified this molecule as a 'hit' during a high-throughput screening campaign for autophagy inducers. A variety of synthetic strategies were utilized to modify the 1,3-diarylpyrazole core at its 1-, 3-, and 4-position. Compounds were assessed in vitro to identify their cytotoxicity properties. Of note, several compounds in the series displayed relevant cytotoxicity, which warrants scrutiny while interpreting biological activities that have been reported for structurally related molecules. In addition, antiparasitic activities were recorded against a range of human-infective protozoa, including Trypanosoma cruzi, T. brucei rhodesiense, and Leishmania infantum. The most interesting compounds displayed low micromolar whole-cell potencies against individual or several parasitic species, while lacking cytotoxicity against human cells.


Subject(s)
Pyrazoles , Trypanosoma cruzi , Pyrazoles/pharmacology , Pyrazoles/chemistry , Pyrazoles/chemical synthesis , Humans , Trypanosoma cruzi/drug effects , Antiparasitic Agents/pharmacology , Antiparasitic Agents/chemical synthesis , Antiparasitic Agents/chemistry , Drug Design , Leishmania infantum/drug effects , Structure-Activity Relationship , Trypanosoma brucei rhodesiense/drug effects , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemical synthesis , Antiprotozoal Agents/chemistry
10.
Ugeskr Laeger ; 186(17)2024 Apr 22.
Article in Danish | MEDLINE | ID: mdl-38704708

ABSTRACT

Leishmaniasis is transmitted by sandflies and involves cutaneous, mucocutaneous, or visceral disease. Sporadic, imported cases in Denmark emphasize the need for greater awareness. The incidence is stable with at least ten verified cases per year. Diagnostic methods include PCR- and antibody tests with a high positivity rate for PCR (17%) and a low positivity rate for antibody (1.4%). The latter should be used only when visceral disease is suspected. Immunosuppressed patients are at particular risk. Treatment strategies are chosen according to the severity of the condition, as argued in this review.


Subject(s)
Leishmaniasis , Humans , Denmark/epidemiology , Leishmaniasis/diagnosis , Communicable Diseases, Imported/diagnosis , Antiprotozoal Agents/therapeutic use , Polymerase Chain Reaction , Leishmaniasis, Cutaneous/diagnosis
11.
Eye Contact Lens ; 50(6): 279-281, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38709240

ABSTRACT

PURPOSE: To report first clinical use of novel medical treatment for Acanthamoeba keratitis. METHODS: Interventional observational case series. Two patients with Acanthamoeba keratitis were unsuccessfully treated with polihexanide (PHMB) 0.02% and propamidine 0.1% for 6 weeks, then all were shifted in a compassionate use of PHMB 0.08% with novel standardized protocol. The postinterventional follow-up of patients was at least 7 months. RESULTS: PHMB 0.08% eyedrops in a novel standardized protocol improved infection resolution and led to complete healing of the lesion after 4 weeks in the two cases. Corneal opacities and neovascularization decreased slowly, best-corrected visual acuity slightly improved and progressively increased in the further 7 months, and no infection recurrence occurred. CONCLUSIONS: This preliminary report of two cases shows promising response to polihexanide 0.08% lowering drastically the illness duration, with reduced chance of recurrence, and mostly improving patients' quality of life.


Subject(s)
Acanthamoeba Keratitis , Biguanides , Acanthamoeba Keratitis/drug therapy , Humans , Biguanides/therapeutic use , Adult , Male , Female , Benzamidines/therapeutic use , Visual Acuity , Ophthalmic Solutions , Antiprotozoal Agents/therapeutic use
12.
J Med Chem ; 67(10): 8323-8345, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38722757

ABSTRACT

Leishmaniasis is a neglected tropical disease that is estimated to afflict over 12 million people. Current drugs for leishmaniasis suffer from serious deficiencies, including toxicity, high cost, modest efficacy, primarily parenteral delivery, and emergence of widespread resistance. We have discovered and developed a natural product-inspired tambjamine chemotype, known to be effective against Plasmodium spp, as a novel class of antileishmanial agents. Herein, we report in vitro and in vivo antileishmanial activities, detailed structure-activity relationships, and metabolic/pharmacokinetic profiles of a large library of tambjamines. A number of tambjamines exhibited excellent potency against both Leishmania mexicana and Leishmania donovani parasites with good safety and metabolic profiles. Notably, tambjamine 110 offered excellent potency and provided partial protection to leishmania-infected mice at 40 and/or 60 mg/kg/10 days of oral treatment. This study presents the first account of antileishmanial activity in the tambjamine family and paves the way for the generation of new oral antileishmanial drugs.


Subject(s)
Antiprotozoal Agents , Leishmania donovani , Leishmania mexicana , Animals , Structure-Activity Relationship , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/therapeutic use , Antiprotozoal Agents/chemical synthesis , Antiprotozoal Agents/pharmacokinetics , Mice , Leishmania donovani/drug effects , Leishmania mexicana/drug effects , Drug Discovery , Humans , Female , Leishmaniasis/drug therapy , Mice, Inbred BALB C
13.
Phytomedicine ; 129: 155640, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38714091

ABSTRACT

BACKGROUND: The discovery of artemisinin, an endoperoxide, encouraged the scientific community to explore endoperoxides as potential anti-parasitic molecules. Although artemisinin derivatives are rapidly evolving as potent anti-malarials, their potential as anti-leishmanials is emerging gradually. The treatment of leishmaniasis, a group of neglected tropical diseases is handicapped by lack of effective vaccines, drug toxicities and drug resistance. The weak antioxidant defense mechanism of the Leishmania parasites due to lack of catalase and a selenium dependent glutathione peroxidase system makes them vulnerable to oxidative stress, and this has been successful exploited by endoperoxides. PURPOSE: The study aimed to review the available literature on the anti-leishmanial efficacy of natural endoperoxides with a view to achieve insights into their mode of actions. METHODS: We reviewed more around 110 research and review articles restricted to the English language, sourced from electronic bibliographic databases including PubMed, Google, Web of Science, Google scholar etc. RESULTS: Natural endoperoxides could potentially augment the anti-leishmanial drug library, with artemisinin and ascaridole emerging as potential anti-leishmanial agents. Due to higher reactivity of the cyclic peroxide moiety, and exploiting the compromised antioxidant defense of Leishmania, endoperoxides like artemisinin and ascaridole potentiate their leishmanicidal efficacy by creating a redox imbalance. Furthermore, these molecules minimally impair oxidative phosphorylation; instead inhibit glycolytic functions, culminating in depolarization of the mitochondrial membrane and depletion of ATP. Additionally, the carbon-centered free radicals generated from endoperoxides, participate in chain reactions that can generate even more reactive organic radicals that are toxic to macromolecules, including lipids, proteins and DNA, leading to cell cycle arrest and apoptosis of Leishmania parasites. However, the precise target(s) of the toxic free radicals remains open-ended. CONCLUSION: In this overview, the spectrum of natural endoperoxide molecules as major anti-leishmanials and their mechanism of action has been delineated. In view of the substantial evidence that natural endoperoxides (e.g., artemisinin, ascaridole) exert a noxious effect on different species of Leishmania, identification and characterization of other natural endoperoxides is a promising therapeutic option worthy of further pharmacological consideration.


Subject(s)
Antiprotozoal Agents , Artemisinins , Leishmania , Peroxides , Leishmania/drug effects , Peroxides/pharmacology , Peroxides/chemistry , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Artemisinins/pharmacology , Artemisinins/chemistry , Humans , Leishmaniasis/drug therapy , Oxidative Stress/drug effects , Animals , Antioxidants/pharmacology
14.
Drug Dev Res ; 85(3): e22194, 2024 May.
Article in English | MEDLINE | ID: mdl-38704828

ABSTRACT

The aim the present study was to investigate the impact of novel pentavalent organobismuth and organoantimony complexes on membrane integrity and their interaction with DNA, activity against Sb(III)-sensitive and -resistant Leishmania strains and toxicity in mammalian peritoneal macrophages. Ph3M(L)2 type complexes were synthesized, where M = Sb(V) or Bi(V) and L = deprotonated 3-(dimethylamino)benzoic acid or 2-acetylbenzoic acid. Both organobismuth(V) and organoantimony(V) complexes exhibited efficacy at micromolar concentrations against Leishmania amazonensis and L. infantum but only the later ones demonstrated biocompatibility. Ph3Sb(L1)2 and Ph3Bi(L1)2 demonstrated distinct susceptibility profiles compared to inorganic Sb(III)-resistant strains of MRPA-overexpressing L. amazonensis and AQP1-mutated L. guyanensis. These complexes were able to permeate the cell membrane and interact with the Leishmania DNA, suggesting that this effect may contribute to the parasite growth inhibition via apoptosis. Taken altogether, our data substantiate the notion of a distinct mechanism of uptake pathway and action in Leishmania for these organometallic complexes, distinguishing them from the conventional inorganic antimonial drugs.


Subject(s)
Antimony , Antiprotozoal Agents , Cell Membrane , Drug Resistance , Organometallic Compounds , Antimony/pharmacology , Antimony/chemistry , Animals , Organometallic Compounds/pharmacology , Mice , Cell Membrane/drug effects , Antiprotozoal Agents/pharmacology , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/parasitology , Leishmania/drug effects , DNA, Protozoan , Leishmania infantum/drug effects , Leishmania infantum/genetics , Mice, Inbred BALB C
15.
Int J Biol Macromol ; 269(Pt 1): 132034, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38702006

ABSTRACT

Parthenium hysterophorus plant has a diverse chemical profile and immense bioactive potential. It exhibits excellent pharmacological properties such as anti-cancer, anti-inflammatory, anti-malarial, microbicidal, and anti-trypanosomal. The present study aims to evaluate the anti-leishmanial potential and toxicological safety of anhydroparthenin isolated from P. hysterophorus. Anydroparthenin was extracted from the leaves of P. hysterophorus and characterized through detailed analysis of 1H, 13C NMR, and HRMS. Dye-based in vitro and ex vivo assays confirmed that anhydroparthenin significantly inhibited both promastigote and amastigote forms of the Leishmania donovani parasites. Both the cytotoxicity experiment and hemolytic assay revealed its non-toxic nature and safety index in the range of 10 to 15. Further, various mechanistic assays suggested that anhydroparthenin led to the generation of oxidative stress, intracellular ATP depletion, alterations in morphology and mitochondrial membrane potential, formation of intracellular lipid bodies, and acidic vesicles, ultimately leading to parasite death. As a dual targeting approach, computational studies and sterol quantification assays confirmed that anhydroparthenin inhibits the Sterol C-24 methyl transferase and Sterol 14-α demethylase proteins involved in the ergosterol biosynthesis in Leishmania parasites. These results suggest that anhydroparthenin could be a promising anti-leishmanial molecule and can be developed as a novel therapeutic stratagem against leishmaniasis.


Subject(s)
Leishmania donovani , Methyltransferases , Sterol 14-Demethylase , Leishmania donovani/drug effects , Leishmania donovani/enzymology , Sterol 14-Demethylase/metabolism , Sterol 14-Demethylase/chemistry , Methyltransferases/metabolism , Methyltransferases/antagonists & inhibitors , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Molecular Docking Simulation , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Membrane Potential, Mitochondrial/drug effects , Computer Simulation , Animals , Humans
16.
Pak J Pharm Sci ; 37(1(Special)): 173-184, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38747267

ABSTRACT

Hydrazones 1-6, azo-pyrazoles 7-9 and azo-pyrimidines 10-15 are compounds that exhibit antibacterial activity. The mode of action and structures of these derivatives have been previously confirmed as antibacterial. In this investigation, biological screening and molecular docking studies were performed for derivatives 1-15, with compounds 2, 7, 8, 14 and 15 yielding the best energy scores (from -20.7986 to -10.5302 kcal/mol). Drug-likeness and in silico ADME prediction for the most potent derivatives, 2, 7, 8, 14 and 15, were predicted (from 84.46 to 96.85%). The latter compounds showed good recorded physicochemical properties and pharmacokinetics. Compound 8 demonstrated the strongest inhibition, which was similar to the positive control (eflornithine) against Trypanosoma brucei brucei (WT), with an EC50 of 25.12 and 22.52µM, respectively. Moreover, compound 14 exhibited the best activity against Leishmania mexicana promastigotes and Leishmania major promastigotes (EC50 =46.85; 40.78µM, respectively).


Subject(s)
Molecular Docking Simulation , Pyrazoles , Pyrimidines , Trypanocidal Agents , Trypanosoma brucei brucei , Pyrimidines/pharmacology , Pyrimidines/chemistry , Pyrimidines/chemical synthesis , Trypanosoma brucei brucei/drug effects , Pyrazoles/pharmacology , Pyrazoles/chemistry , Trypanocidal Agents/pharmacology , Trypanocidal Agents/chemistry , Trypanocidal Agents/chemical synthesis , Leishmania mexicana/drug effects , Leishmania major/drug effects , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Computer Simulation , Azo Compounds/pharmacology , Azo Compounds/chemistry , Azo Compounds/chemical synthesis , Structure-Activity Relationship , Parasitic Sensitivity Tests
17.
An Acad Bras Cienc ; 96(2): e20230375, 2024.
Article in English | MEDLINE | ID: mdl-38747836

ABSTRACT

In pursuit of potential agents to treat Chagas disease and leishmaniasis, we report the design, synthesis, and identification novel naphthoquinone hydrazide-based molecular hybrids. The compounds were subjected to in vitro trypanocide and leishmanicidal activities. N'-(1,4-Dioxo-1,4-dihydronaphthalen-2-yl)-3,5-dimethoxybenzohydrazide (13) showed the best performance against Trypanosoma cruzi (IC50 1.83 µM) and Leishmania amazonensis (IC50 9.65 µM). 4-Bromo-N'-(1,4-dioxo-1,4-dihydronaphthalen-2-yl)benzohydrazide (16) exhibited leishmanicidal activity (IC50 12.16 µM). Regarding trypanocide activity, compound 13 was low cytotoxic to LLC-MK2 cells (SI = 95.28). Furthermore, through molecular modeling studies, the cysteine proteases cruzain, rhodesain and CPB2.8 were identified as the potential biological targets.


Subject(s)
Drug Design , Hydrazines , Leishmania , Naphthoquinones , Trypanocidal Agents , Trypanosoma cruzi , Naphthoquinones/pharmacology , Naphthoquinones/chemistry , Naphthoquinones/chemical synthesis , Trypanosoma cruzi/drug effects , Trypanocidal Agents/pharmacology , Trypanocidal Agents/chemical synthesis , Trypanocidal Agents/chemistry , Leishmania/drug effects , Hydrazines/chemistry , Hydrazines/pharmacology , Animals , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemical synthesis , Antiprotozoal Agents/chemistry , Parasitic Sensitivity Tests , Inhibitory Concentration 50 , Structure-Activity Relationship , Cysteine Endopeptidases
18.
PLoS Negl Trop Dis ; 18(4): e0012134, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38669211

ABSTRACT

BACKGROUND: Currently available treatment options are mostly effective in achieving long-term cure in visceral leishmaniasis (VL) patients. However, there have been reports of recurrence of this illness in both immunosuppressed and immunocompetent patients. CASE PRESENTATION: We report the first case of recurrent VL relapse in a 19-year-old immunocompetent female with functional hypopituitarism (hypogonadotropic hypogonadism with central hypothyroidism) from Bangladesh, who has been treated three times previously with optimal dosage and duration- liposomal amphotericin B (LAmB) alone and in combination with miltefosine. We treated the patient successfully with a modified treatment regimen of 10 mg/kg body weight LAmB for two consecutive days along with oral miltefosine for seven days as loading dose. For secondary prophylaxis, the patient received 3 mg/kg body weight LAmB along with oral miltefosine for seven days monthly for five doses followed by hormonal replacement. The patient remained relapse free after 12 months of her treatment completion. CONCLUSION: In the absence of protective vaccines against Leishmania species and standard treatment regimen, this modified treatment regimen could help the management of recurrent relapse cases.


Subject(s)
Amphotericin B , Antiprotozoal Agents , Hypopituitarism , Leishmaniasis, Visceral , Phosphorylcholine , Recurrence , Female , Humans , Young Adult , Amphotericin B/therapeutic use , Amphotericin B/administration & dosage , Antiprotozoal Agents/therapeutic use , Antiprotozoal Agents/administration & dosage , Bangladesh , Hypopituitarism/drug therapy , Leishmaniasis, Visceral/drug therapy , Phosphorylcholine/analogs & derivatives , Phosphorylcholine/therapeutic use , Phosphorylcholine/administration & dosage , Treatment Outcome , Adult
19.
Acta Derm Venereol ; 104: adv35089, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38682801

ABSTRACT

Israel is endemic for Old-World cutaneous leishmaniasis. The most common species is Leishmania major. However, the available treatment options are limited. This study's objective was to compare the authors' experience with different antimony intralesional treatments of Leishmania major cutaneous leishmaniasis. A retrospective evaluation was undertaken for cases of Leishmania major cutaneous leishmaniasis treated by pentavalent antimony in a university-affiliated medical centre in Israel. The previous treatment of intralesional sodium stibogluconate (Pentostam®) was compared with the current treatment of meglumine antimoniate (Glucantime®). One hundred cases of cutaneous leishmaniasis were treated during the study period, of whom 33 were treated with intralesional sodium stibogluconate and 67 were treated with intralesional meglumine antimoniate. The patients were 78 males and 22 females, mean age 24 (range 10-67) and there was a total of 354 skin lesions. Within 3 months from treatment, 91% (30/33) of the intralesional sodium stibogluconate group and 88% (59/67) of the intralesional meglumine antimoniate group had complete healing of the cutaneous lesions after an average of 3 treatment cycles (non-statistically significant). In conclusion, the 2 different medications have the same efficacy and safety for treating cutaneous leishmaniasis. Pentavalent antimoniate intralesional infiltration treatment is safe, effective, and well tolerated with minimal side effects for Old-World cutaneous leishmaniasis.


Subject(s)
Antimony Sodium Gluconate , Antiprotozoal Agents , Injections, Intralesional , Leishmania major , Leishmaniasis, Cutaneous , Meglumine Antimoniate , Humans , Meglumine Antimoniate/administration & dosage , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Cutaneous/diagnosis , Female , Male , Antimony Sodium Gluconate/administration & dosage , Retrospective Studies , Adult , Antiprotozoal Agents/administration & dosage , Antiprotozoal Agents/adverse effects , Middle Aged , Leishmania major/drug effects , Aged , Young Adult , Adolescent , Treatment Outcome , Child , Time Factors , Israel , Meglumine/administration & dosage , Organometallic Compounds/administration & dosage
20.
Acta Trop ; 255: 107201, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38604329

ABSTRACT

Reportedly, synthetic drugs such as metronidazole, furazolidone, tinidazole, and quinacrine are used for the treatment of giardiasis but are associated with adverse effects. In this study, we aimed to investigate the in vitro and in vivo effects of eucalyptol (ECT, 1,8 cineole) alone and in combination with metronidazole (MNZ) on Giardia lamblia. The effects of ECT on cell viability, plasma membrane permeability, and gene expression levels of adenylate cyclase (AK) and extracellular signal kinases 1 and 2 (ERK1 and ERK2) in trophozoites of G. lamblia were assessed. In vivo, the effects of ECT alone and in combination with MNZ were assessed on mice infected with G. lamblia. In addition, the gene expression of inflammatory genes (e.g., TNF-α, IL-1ß, and IL-10) and antioxidant genes (catalase (CAT), superoxide dismutase 1 (SOD1), glutathione peroxidase 2 (GPX2)) was determined by real-time PCR. The IC50 values of ECT, MNZ, and ECT+MNZ on trophozoites were 30.2 µg/mL, 21.6 µg/mL, and 8.5 µg/mL, respectively. The estimated Fractional inhibitory concentration index (FICI) values for ECT and MNZ were 0.28 and 0.39, respectively. The application of ECT on G. lamblia trophozoites resulted in a dose-dependent increase in plasma membrane permeability, particularly at concentrations of ½ IC50 and IC50 (P < 0.05). The treatment of infected mice with various doses of ECT, mainly in combination with MNZ for 7 days, resulted in a significant decrease (P < 0.001) in the average number and viability of cysts. ECT, especially when combined with MNZ, caused a significant (P < 0.001) reduction in the expression of TNF-α and IL-6 genes, and an increase (P < 0.05) in the expression of IL-10 genes. ECT alone and mainly in combination with MNZ leads to a significant (P < 0.001) increase in the gene expression of CAT, SOD, and GPX genes. These findings demonstrate that the use of ECT in these doses, even for 14 days, does not have any toxic effects on the function of vital liver and kidney tissues. The study findings confirmed the promising effects of ECT against G. lamblia infection both in vitro and in vivo. Considering the possible mechanisms, ECT increases plasma membrane permeability and reduces the expression levels of infectivity-related genes. In addition, ECT suppresses inflammation and oxidative stress, controlling giardiasis in mice. More studies are needed to clarify these findings.


Subject(s)
Antiprotozoal Agents , Giardia lamblia , Giardiasis , Oxidative Stress , Animals , Giardia lamblia/drug effects , Oxidative Stress/drug effects , Mice , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/therapeutic use , Giardiasis/drug therapy , Giardiasis/parasitology , Inflammation/drug therapy , Metronidazole/pharmacology , Cell Survival/drug effects , Disease Models, Animal , Cell Membrane Permeability/drug effects , Female , Trophozoites/drug effects , Mice, Inbred BALB C , Inhibitory Concentration 50 , Cytokines/metabolism
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