Treatment Of Cutaneous Leishmaniasis Research Articles

Enhanced topical paromomycin delivery for cutaneous leishmaniasis treatment: Passive and iontophoretic approaches

Conventional treatments for cutaneous leishmaniasis, a neglected vector-borne infectious disease, can frequently lead to serious adverse effects. Paromomycin (PAR), an aminoglycoside antibiotic, has been suggested for the topical treatment of disease-related lesions, but even when formulated in high drug-loading dosage forms, presents controversial efficacy. The presence of five ionizable amino groups hinder its passive cutaneous penetration but make PAR an excellent candidate for iontophoretic delivery. The objective of this study was to verify the feasibility of using iontophoresis for cutaneous PAR delivery and to propose a topical passive drug delivery system that could be applied between iontophoretic treatments. For this, in vitro iontophoretic experiments evaluated different application durations (10, 30, and 360 min), current densities (0.1, 0.25, and 0.5 mA/cm2), PAR concentrations (0.5 and 1.0 %), and skin models (intact and impaired porcine skin). In addition, 1 % PAR hydrogel had its penetration profile compared to 15 % PAR ointment in passive transport. Results showed iontophoresis could deliver suitable PAR amounts to dermal layers, even in short times and with impaired skin. Biodistribution assays showed both iontophoretic transport and the proposed hydrogel delivered higher PAR amounts to deeper skin layers than conventional ointment, even though applying 15 times less drug. To our knowledge, this is the first report of PAR drug delivery enhancement by iontophoresis. In summary, the association of iontophoresis with a topical application of PAR gel seems appropriate for improving cutaneous leishmaniasis treatment.

An in vitro study of the antileishmanial and cytotoxic activity of extracts of Sclerolobium paniculatum (Fabaceae)

Leishmaniasis is a neglected endemic disease and the pharmacotherapy indicated is expensive, in addition to the unwanted effects generated by the drugs, resulting in low adherence to treatment. Therefore, the search for therapeutic alternatives includes the use of medicinal plants, such as Sclerolobium paniculatum Vogel, which has antioxidant, healing and antifungal properties. Therefore, the aim of this study was to evaluate the in vitro antileishmanial activity of the methanolic and hexanic extracts of S. paniculatum against the promastigote forms of Leishmania (L.) amazonensis and Leishmania (V.) guyanensis and their toxicity in J774 macrophages. As a result, the hexanic extract was considered active against L. guyanensis with an IC50 of 40 μg mL-1 over 48 hours, with no significant activity for L. amazonensis with an IC50 above 100 μg mL-1 over 24 and 48 hours. The methanolic extract showed moderate activity against L. guyanensis, with an IC50 of 82 μg mL-1 over 48 hours and an IC50 of 67 μg mL-1 over 48 hours against L. amazonensis, making it moderately active. Both extracts did not present cytotoxic profiles at any of the concentrations, being recommended for future research with other species of Leishmania sp. to optimize the treatment of cutaneous leishmaniasis.

Cheminformatics-based discovery of new organoselenium compounds with potential for the treatment of cutaneous and visceral leishmaniasis

Leishmaniasis affects more than 12 million humans globally and a further 1 billion people are at risk in leishmaniasis endemic areas. The lack of a vaccine for leishmaniasis coupled with the limitations of existing anti-leishmanial therapies prompted this study. Cheminformatic techniques are widely used in screening large libraries of compounds, studying protein-ligand interactions, analysing pharmacokinetic properties, and designing new drug molecules with great speed, accuracy, and precision. This study was undertaken to evaluate the anti-leishmanial potential of some organoselenium compounds by quantitative structure-activity relationship (QSAR) modeling, molecular docking, pharmacokinetic analysis, and molecular dynamic (MD) simulation. The built QSAR model was validated (R2 train = 0.8646, R2 test = 0.8864, Q2 = 0.5773) and the predicted inhibitory activity (pIC50) values of the newly designed compounds were higher than that of the template (Compound 6). The new analogues (6a, 6b, and 6c) showed good binding interactions with the target protein (Pyridoxal kinase, PdxK) while also presenting excellent drug-likeness and pharmacokinetic profiles. The results of density functional theory, MD simulation, and molecular mechanics generalized Born surface area (MM/GBSA) analyses suggest the favourability and stability of protein-ligand interactions of the new analogues with PdxK, comparing favourably well with the reference drug (Pentamidine). Conclusively, the newly designed compounds could be synthesized and tested experimentally as potential anti-leishmanial drug molecules. Communicated by Ramaswamy H. Sarma

Nitazoxanide and quercetin co-loaded nanotransfersomal gel for topical treatment of cutaneous leishmaniasis with macrophage targeting and enhanced anti-leishmanial effect

PurposeAnti-leishmanial medications administered by oral and parenteral routes are less effective for treatment of cutaneous leishmaniasis (CL) and cause toxicity, hence targeted drug delivery is an efficient way to improve drug availability for CL with reduced toxicity. This study aimed to develop, characterize and evaluate nitazoxanide and quercetin co-loaded nanotransfersomal gel (NTZ-QUR-NTG) for the treatment of CL. MethodsNTZ-QUR-NT were prepared by thin film hydration method and were statistically optimized using Box-Behnken design. To ease the topical delivery and enhance the retention time, the NTZ-QUR-NT were dispersed in 2 % chitosan gel. Moreover, in-vitro drug release, ex-vivo permeation, macrophage uptake, cytotoxicity and anti-leishmanial assays were performed. ResultsThe optimized formulation indicated mean particle size 210 nm, poly dispersity index (PDI) 0.16, zeta potential (ZP) −15.1 mV and entrapment efficiency (EE) of NTZ and QUR was 88 % and 85 %, respectively. NTZ-QUR-NT and NTZ-QUR-NTG showed sustained release of the incorporated drugs as compared to the drug dispersions. Skin permeation of NTZ and QUR in NTZ-QUR-NTG was 4 times higher in comparison to the plain gels. The NTZ-QUR-NT cell internalization was almost 10-folds higher than NTZ-QUR dispersion. The cytotoxicity potential (CC50) of NTZ-QUR-NT (71.95 ± 3.32 μg/mL) was reduced as compared to NTZ-QUR dispersion (49.77 ± 2.15 μg/mL. A synergistic interaction was found between NTZ and QUR. Moreover, in-vitro anti-leishmanial assay presented a lower IC50 value of NTZ-QUR-NT as compared to NTZ-QUR dispersion. Additionally, a significantly reduced lesion size was observed in NTZ-QUR-NTG treated BALB/c mice, indicating its antileishmanial potential. ConclusionIt can be concluded that nanotransfersomal gel has the capability to retain and permeate the incorporated drugs through stratum corneum and induce synergetic anti-leishmanial effect of NTZ and QUR against cutaneous leishmaniasis.

Clinical Risk Factors of Systemic Antimony Treatment Failure in Patients with Acute Cutaneous leishmaniasis referred to the Dermatology Clinics of Mashhad University of Medical Sciences, Iran

Background: Systemic or topical forms of pentavalent antimony compounds such as meglumine antimoniate (MA) are used as standard treatment for cutaneous leishmaniasis (CL). However, an increasing number of studies demonstrate evidence of treatment failure with these drugs. The objective of this study was to determine the factors associated with systemic MA treatment failure in patients with acute CL. Methods: In this case-control study, patients with urban cutaneous referred to leishmaniasis clinics in Mashhad from 2017 to 2018 were followed up 12 months after the start of treatment and were evaluated for improvement or failure according to the national leishmaniasis protocol. Results: A total of 112 cases of CL (59 men and 53 women) with a mean age of 23.3±21.11 years were studied. The number of patients with clinical improvement was significantly higher in women (P=0.005). Age, body mass index (BMI), occupation and education, the possible infection and living location, past medical, drug and leishmaniasis recurrence history, lesion’s characteristics and ulceration were also significantly different between the two groups of improved and unhealed patients. Conclusion: The results of this study showed that the male sex, age less than 18 years, receiving pentostam, previous treatment history, lymphadenopathy, urban leishmaniasis, duration of illness more than 4 months, having a single lesion especially on the face, BMI less than 18 kg/m2 and a lesion size of more than 3 cm is more common in patients with treatment failure.

Synergistic combination of Cinnamomum verum and Syzygium aromaticum treatment for cutaneous leishmaniasis and investigation of their molecular mechanism of action

ABSTRACT Combination therapy at appropriately suitable doses presents a promising alternative to monotherapeutic drugs. In this study, Cinnamomum verum and Syzygium aromaticum essential oils and their major compounds have exhibited substantial leishmaniacidal potential against both promastigote and amastigote forms of Leishmania (L.) major. However, they displayed high cytotoxicity against Raw264.7 macrophage cells. Interestingly, when combined with each other or with amphotericin B, they demonstrated a synergistic effect (FIC<0.5) with low cytotoxicity. These combinations are able to modulate the production of nitric oxide (NO) by macrophages. Notably, the combination of S. aromaticum Essential oil with amphotericin B stimulates macrophage cells by increasing NO production to eliminate leishmanial parasites. Furthermore, investigation of the molecular mechanism of action of these synergistic combinations reveals potent inhibition of the sterol pathway through the inhibition of the CYP51 gene expression. The findings suggest that combination therapy may offer significant therapeutic benefits in both food and pharmaceutical fields.

Community-based treatment of cutaneous leishmaniasis using cryotherapy and miltefosine in Southwest Ethiopia: the way forward?

Cutaneous leishmaniasis (CL) is a common, yet massively underreported skin morbidity in Ethiopia. Most patients never seek treatment, as this is offered only in specialized treatment centers. Early diagnosis and treatment through decentralization is crucial to decrease transmission and to reach the NTD roadmap goals. However, little information is available on outcomes and challenges of community-based treatment initiatives. A community-based prospective cohort study was conducted in Ochollo. Patients with clinically or microscopy confirmed CL were included. Cryotherapy was (to be) given weekly with at least four sessions for uncomplicated lesions, and miltefosine was given for 4 weeks for complicated lesions. Miltefosine adherence was assessed by counting pill strips. Clinical and patient-reported outcomes (dermatological life quality index and patient-global assessment) were assessed at month 6 (M6). A total of 107 patients were included, with a median age of 6 years. Two patients refused, and 15 could not be treated as they were too young (<4 years) for miltefosine. Giving cryotherapy to patients weekly was not feasible due to long wound healing times and required use of topical antibiotics. Only 52.4% of miltefosine patients finished >90% of their tablets by M1. Among 46 patients treated with cryotherapy, 24 (52.2%) were cured at M6, and 9 (19.6%) had substantial improvement. The cure rate was 16/39 (41.0%) for miltefosine with 28.2% (11/39) substantial improvement. Before treatment, more than half (57.8%) of patients reported that CL did not negatively impact their life, which significantly increased to 95.2% at M6. At this time, 61.7% of patients said their lesion was clear, which was 1% before treatment. Our study is the first to identify the challenges and opportunities of miltefosine and cryotherapy for community treatment of CL. Although overall cure rates were lower than expected, patient-reported outcomes were generally positive and quite some patients had good improvement.

Protocol for a prospective observational cohort study of cutaneous leishmaniasis in Ethiopia

Background: Cutaneous leishmaniasis (CL) is a skin neglected tropical disease, with an estimated 40,000 new cases each year in Ethiopia. CL causes ulcers, nodules, and plaques on the skin, and in some instances the destruction of the nasopharyngeal mucosa and cartilage. Some CL lesions may heal spontaneously, whilst other lesions may require therapies which are associated with discomfort, adverse effects, prolonged treatment, and a frequent lack of a complete response. Scarring, a sequela of CL, causes permanent disfigurement and is associated with stigma linked with a reduction in health-related quality of life. The choice of treatment for CL is based upon factors including the causative species; the number, extent, size, and location of lesions; and the availability of treatments. The development of robust evidence for CL treatment is hindered by a lack of validated and appropriate outcome measures and few data to support hypothesis-generation and trial design. There is a paucity of prospective data with well-defined treatment outcomes for CL caused by L. aethiopica. Aim: The overall aim of this study is to improve the understanding of the health and economic burden of CL. Methods: We have designed an observational, multi-centre cohort study to examine treatment outcomes for CL in Ethiopia which includes clinical outcomes, laboratory outcomes, patient reported outcome measures, scar assessments and cost effectiveness. We aim to recruit up to 750 participants across two hospital sites. We present here the protocol for this cohort study with a 12-month follow up period for each participant. Conclusions: These data will inform the design of randomized controlled trials to evaluate new treatment strategies, with appropriate economic evaluations. This will help improve evidence-based guidelines and support evidence-led policy decisions, not only in Ethiopia but also globally.

Microemulsion based on methyl 3,4,5-trihydroxybenzoate for the topical treatment of cutaneous leishmaniasis: an in vivo assay

ABSTRACT Cutaneous leishmaniasis, caused by protozoa of the genus Leishmania, presents diverse clinical manifestations, and current therapeutic options have limitations, including long treatment periods, potential hospitalization, and excessive pain during treatment. Methyl gallate, a phenolic compound found in plants such as Libidibia ferrea, presents promising antileishmanial activity. Combining this compound with existing leishmaniasis medications could lead to reduced dosages and the minimization of side effects. This study aimed to assess the efficacy of a microemulsion containing methyl gallate, either on its own or in combination with Glucantime®, for the experimental treatment of cutaneous leishmaniasis in a 30-day in vivo assay using golden hamsters infected with Leishmania (Leishmania) amazonensis. The control groups included an untreated positive control and an uninfected, untreated negative control. After treatment, we evaluated clinical, parasitological, and biochemical parameters. While none of the treatments achieved clinical or parasitological cure, notable improvements were observed in the combined group, with significant reductions in snout skin lesions and parasite load when compared to the control. Biochemical parameters such as creatinine, CK-MB, GOT, and GPT remained unchanged, but urea and CPK levels significantly increased in all the experimental groups relative to the control. In conclusion, the integration of a topical methyl gallate microemulsion with intralesional Glucantime® showed potential as an effective treatment for cutaneous leishmaniasis. Further investigations into optimal dosages and therapeutic schemes are warranted in order to enhance treatment outcomes.

Tratamiento tópico de leishmaniasis cutánea con crema- nanoemulsión de un compuesto genérico antimonial pentavalente. Caso clínico.

Introduction. An effective vaccine against cutaneous leishmaniasis has yet to be developed. Treatment of the disease relies on painful intramuscular administration of high doses of compounds based on pentavalent antimony, causing adverse effects. New therapeutic options effective, easy to apply, cheap and without adverse effects are urgently required. Case report. A 26-year-old male patient showing a large facial ulcer, presumptively by cutaneous leishmaniasis, diagnostic confirmed by Montenegro’s skin test and microscopical observation of amastigote forms. Due to the ulcer’s location and size, topical treatment with a nanoemulsion cream-based on a generic antimony-compound was attempted. The cream was applied twice daily and was rapidly absorbed. After 2 months of treatment, no discomfort or other adverse effects were detected. The ulcer was replaced with healthy skin tissue and a soft, clean scar. Conclusion. The novel cream, which was rapidly absorbed, effective, cheaper than standard systemic therapy and self-applied by the patient, showed potential value in the treatment of cutaneous leishmaniasis.

Naloxone Effects against Cutaneous Leishmaniasis Caused by Leishmania major Strain MRHO/IR/75/ER in the BALB/c Mice.

Cutaneous leishmaniasis (CL) is a serious health problem in some parts of the world, such as Iran. Since the use of pentavalent antimonial compounds such as meglumine antimoniate (Glucantime, MA) for the treatment of CL has side effects, naloxone as a new treatment in the footpad of Leishmania major (L. major)-infected BALB/c mice was investigated by evaluating the lesion size and the parasite burden. The animals were infected with L. major (MRHO/IR/75/ER). 40 BALB/c mice were divided into 4 groups (10/group), and were treated as follows 39 days after L. major infection: Group 1 treated with intraperitoneal injections of MA (100 mg/kg, positive control group) daily for six weeks; Group 2 received a 100 μl injection of PBS (negative control group); Group 3 received subcutaneous (SC) injections of naloxone (10 mg/kg) daily for six weeks (Naloxone1), and Group 4 was SC injected with naloxone (10 mg/kg) weekly for six weeks (Naloxone2). The lesion size was measured using a digital caliper. After the end of treatment, the lesion parasite burden was evaluated. As compared to the negative control group, the groups that received MA and naloxone (groups 1, 3, and 4) showed fewer parasites. CONCLUSION; Also, the naloxone-treated mice showed significantly smaller lesion sizes than the negative control group (p˂0.05), but they did not differ significantly from the MA-treated mice. Taken together, the results suggest that naloxone might be a promising and alternative treatment for CL.

Evaluation of farnesol orally and topically against experimental cutaneous leishmaniasis: In -vivo analysis.

Leishmaniasis is a zoonotic disease transmitted by an obligate intra-macrophage protozoan of the genus Leishmania through the infective bite of a vector sandfly. This study investigated the therapeutic efficacy of farnesol, a sesquiterpene compound, for the treatment of cutaneous leishmaniasis (CL) using in vivo BALB/c mouse model. In this study, farnesol's efficacy was compared with the standard drug, paromomycin. It was observed that farnesol significantly reduced lesion sizes and footpad thickness compared to the control group (paromomycin). Lymph node size was also significantly reduced in farnesol-treated mice, indicating its ability to control infection spread. Combination therapy with farnesol and Paromomycin did not demonstrate synergistic effects. These results highlight the potential of farnesol as an alternative therapeutic agent for CL. Further investigations are required to elucidate its mechanism of action and assess potential off-target effects. Optimization of oral delivery methods should be explored to enhance bioavailability. Overall, our findings support farnesol's efficacy in CL treatment, offering promising prospects for improved disease management.

Treatment of Cutaneous Leishmaniasis with Sodium Stibogluconate and Allopurinol in a Routine Setting in Ethiopia: Clinical and Patient-Reported Outcomes and Operational Challenges.

Cutaneous leishmaniasis (CL) is common in Ethiopia, but the national guideline does not offer specific treatment recommendations. Consequently, different treatment regimens are used in the country, without quality evidence. In Boru Meda Hospital, sodium stibogluconate (SSG) is routinely used in combination with allopurinol for systemic CL treatment, although evidence on its effectiveness is limited. An observational cohort study was carried out to document clinical treatment outcomes in patients receiving SSG/allopurinol at the end of each 28-day treatment cycle and after 180 days. Patient-reported outcomes were assessed by asking patients to rate lesion severity, and by the dermatological life quality index. A total of 104 patients were included. After one treatment cycle, only four patients were clinically cured, although patient-reported outcomes significantly improved. The majority (88) of patients were appointed for a second treatment cycle, of whom only 37 (42%) attended. Among the 36 patients who came for final outcome assessment, 50% were cured. Follow-up and treatment were severely affected by conflict; drug stock-outs and insufficient ward capacity for treatment were additional challenges. The treatment outcomes of SSG/allopurinol were relatively poor, and most patients required more than one cycle of treatment. Shortages of drugs and beds indicate the existing gaps in providing CL treatment in Ethiopia.

A Novel Topical Formulation of the Leishmaniasis Drug Glucantime as a Nanostructured Lipid Carrier-Based Hydrogel.

Leishmaniasis is a parasitic disease caused by Leishmania parasites. Meglumine antimoniate, or Glucantime, is the primary drug used to treat this disease. Glucantime with a standard painful injection administration route has high aqueous solubility, burst release, a significant tendency to cross into aqueous medium, rapid clearance from the body, and insufficient residence time at the injury site. Topical delivery of Glucantime can be a favorable option in the treatment of localized cutaneous leishmaniasis. In this study, a suitable transdermal formulation in the form of nanostructured lipid carrier (NLC)-based hydrogel containing Glucantime was prepared. In vitro drug release studies confirmed controllable drug release behavior for hydrogel formulation. An invivo permeation study on healthy BALB/C female mice confirmed appropriate penetration of hydrogel into the skin and sufficient residence time in the skin. In vivo performance of the new topical formulation on the BALB/C female mice showed a significant improvement in reduction of leishmaniasis wound size, lowering parasites number in lesions, liver, and spleen compared with commercial ampule. Hematological analysis showed a significant reduction of the drug's side effects, including variance of enzymes and blood factors. NLC-based hydrogel formulation is proposed as a new topical administration to replace the commercial ampule.

Application of CL Detect™ rapid test for diagnosis and liposomal amphotericin B for treatment of cutaneous leishmaniasis: A retrospective analysis from a tertiary care centre in a non-endemic area in India.

Background Increasing urbanisation has led to the occurrence of cutaneous leishmaniasis (CL) in new areas, which was otherwise localised to endemic areas. Healthcare workers should be made aware of this entity to ensure clinical suspicion of CL and investigations needed to confirm CL. The article describes patients seen at a tertiary hospital in Delhi. Aims To establish the utility of the CL Detect Rapid test as a diagnostic tool and the efficacy of Liposomal Amphotericin B (LAmB) for the complete cure of CL patients. Methods Data of patients of CL (n = 16) was retrospectively analysed concerning diagnosis and treatment. Diagnosis rested on histopathology, real-time PCR, and CL Detect Rapid Test. Speciation of the parasite was based on the Internal transcribed spacer-I gene. Patients were treated with LAmB (i.v., 5 mg/kg up to three doses, five days apart). Results A positivity of 81.3% (95%CI, 54.4-96) was observed for CL Detect Rapid test in comparison with 100% (95%CI, 79.4-100.0) for real-time PCR and 43.8% (95%CI, 19.8-70.1) for microscopy/histopathological examination. L. tropica was the infective species in all cases. All the patients treated with LAmB responded to treatment, and 9/10 patients demonstrated complete regression of lesions, while one was lost to follow-up. Limitations It is a retrospective study, and the data includes only confirmed cases of CL at a single centre. Conclusion This study highlights the utility of CL Detect as a promising diagnostic tool and the efficacy of LAmB for the complete cure of CL.

Therapeutic response and safety of different treatments for cutaneous leishmaniasis in patients: A retrospective cross-sectional study

Objective: To analyze the therapeutic response and safety of different treatments for cutaneous leishmaniasis, received by patients in the Program for the Study and Control of Tropical Diseases- PECET-Medellín-Colombia. Methods: This is a retrospective cross-sectional study of patients attended at PECET Research Center during 2016-2021. Relevant information regarding sociodemographic characteristics, history of leishmaniasis, characterization of current infection, treatment received, follow-up of therapeutic response and safety was collected from the medical records. Data were analyzed with Pearson's Chi-square association tests and Mann-Whitney U test using statistical software. Results: A total of 486 clinical records of patients were analyzed, and 356 received treatment. Eight different therapeutic alternatives (systemic, local and in combination) were analyzed. The therapeutic response of the different alternatives used (except thermotherapy) was higher than 50%. Most frequent adverse events were myalgias, arthralgias and headache, and vesicles for systemic and local treatment, respectively. Conclusions: Safety profile and performance of local therapeutic alternatives and combined schemes for the treatment of uncomplicated cutaneous leishmaniasis are an interesting option for the management of the disease.

In vitro evaluation of herbal based Lesh Nat B cream against Leishmania tropica.

Pentavalent antimonials continue to be the standard treatment for cutaneous leishmaniasis. But their use is retarded owing to highly-priced, prolonged hospitalization, noxious and poor solubility. Therefore, there is a dire need to characterize new potential compounds possessing anti-leishmanial activity. Topical therapies that are more successful are an essential alternative therapeutic option for the localized self-limiting form of this disease. We tested the herbal-based topical cream Lesh Nat B against Leishmania tropica KWH23 promastigotes and axenic amastigotes in vitro. The anti-leishmanial activity of Lesh Nat B cream was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay against promastigotes and axenic amastigotes. The results of Lesh Nat B cream were concentration and incubation time-dependent. After 72h of incubation, Lesh Nat B cream efficiently suppresses the promastigote form of the parasite, followed by 48h and 24h. At 72h, the lowest and highest levels of activity were 37% and 90%. Amastigotes had a minimum activity of 34% and a maximum activity of 78.5%, respectively. This formulation was more cytotoxic against promastigote form than amastigotes form at 72h incubation periods. All the experiments were carried out in triplicates. Half-maximal inhibitory concentration (IC50) values were determined to be (66ug/ml) and (70ug/ml) against promastigote and amastigote forms, respectively. Moreover, 1.63% hemolytic activity was observed in Lesh Nat B cream at (10µg/ml) while 3% hemolytic activity was observed at (37µg/ml). It can be concluded that Lesh Nat B cream demonstrated effective Leishmanicidal and less hemolytic activity and can be used as an alternative therapeutic option for the treatment of cutaneous leishmaniasis; however, more studies are expected to justify its effectiveness in treating cutaneous leishmaniasis in both humans and animals.

Cysteinyl-leukotrienes promote cutaneous Leishmaniasis control.

Leishmaniasis is a neglected tropical parasitic disease with few approved medications. Cutaneous leishmaniasis (CL) is the most frequent form, responsible for 0.7 - 1.0 million new cases annually worldwide. Leukotrienes are lipid mediators of inflammation produced in response to cell damage or infection. They are subdivided into leukotriene B4 (LTB4) and cysteinyl leukotrienes LTC4 and LTD4 (Cys-LTs), depending on the enzyme responsible for their production. Recently, we showed that LTB4 could be a target for purinergic signaling controlling Leishmania amazonensis infection; however, the importance of Cys-LTs in the resolution of infection remained unknown. Mice infected with L. amazonensis are a model of CL infection and drug screening. We found that Cys-LTs control L. amazonensis infection in susceptible (BALB/c) and resistant (C57BL/6) mouse strains. In vitro, Cys-LTs significantly diminished the L. amazonensis infection index in peritoneal macrophages of BALB/c and C57BL/6 mice. In vivo, intralesional treatment with Cys-LTs reduced the lesion size and parasite loads in the infected footpads of C57BL/6 mice. The anti-leishmanial role of Cys-LTs depended on the purinergic P2X7 receptor, as infected cells lacking the receptor did not produce Cys-LTs in response to ATP. These findings suggest the therapeutic potential of LTB4 and Cys-LTs for CL treatment.

Treatment of Cutaneous Leishmaniasis with Allopurinol Plus Itraconazole in Iran.

Cutaneous leishmaniasis (CL) is a serious tropical disease and a neglected health challenge in Iran. Although limited data are available regarding anthroponotic CL, cases resistant to meglumine antimoniate (Glucantime) are increasingly being reported. Via an open-label noncontrolled case series, allopurinol (10 mg/kg/day) plus itraconazole (3-4 mg/kg/day) were orally administered for 1 month to 27 patients (56 lesions) with anthroponotic CL, most of whom were resistant to Glucantime. A mean lesion size of 3.5 ± 1.9 cm at baseline was reduced to 0.6 ± 1.0 after 1 month of treatment. Excellent treatment response was observed in 85.7% of lesions after 1 month. Recurrence only occurred in one patient in the 3-month follow-up session. This study presents preliminary evidence that oral allopurinol plus itraconazole could be an effective treatment in patients with anthroponotic CL.

Promising natural products for the treatment of cutaneous leishmaniasis: A review of in vitro and in vivo studies

Although there are available treatments for cutaneous leishmaniasis (CL), the drugs used are far from ideal, toxic, and costly, in addition to the challenge faced by the development of resistance. Plants have been used as a source of natural compounds with antileishmanial action. However, few have reached the market and become phytomedicines with registration in regulatory agencies. Difficulties related to the extraction, purification, chemical identification, efficacy, safety, and production in sufficient quantity for clinical studies, hinder the emergence of new effective phytomedicines against leishmaniasis. Despite the difficulties reported, the major research centers in the world see that natural products are a trend concerning the treatment of leishmaniasis. The present work consists of a literature review of articles with in vivo studies, covering the period from January 2011 to December 2022, providing an overview of promising natural products for CL treatment. The papers show encouraging antileishmanial action of natural compounds with reduced parasite load and lesion size in animal models, suggesting new strategies for the treatment of the disease. The results reported in this review show advances in using natural products as safe and effective formulations, which can stimulate clinical studies to establish clinical therapy. In conclusion, the information in this review article serves as a preliminary basis for establishing a therapeutic protocol for future clinical trials that can validate the safety and efficacy of natural compounds, providing the development of affordable and safe phytomedicines for the treatment of CL.