The impact of cholesteryl ester transfer protein on the progression of cutaneous leishmaniasis.

Introduction: Pathogenesis of cutaneous leishmaniases involves parasite growth, persistent inflammation, and likely participation of lipoproteins (LP). The cholesteryl ester transfer protein (CETP), involved in LP remodeling, has been shown to participate in the inflammatory response and the evolution of infectious conditions. Methods: We evaluated the impact of the presence of CETP on infection by Leishmania (L.) amazonensis in an experimental model of cutaneous leishmaniasis using C57BL6/J mice transgenic for human CETP (CETP), having as control their littermates that do not express the protein, wild-type (WT) mice. The progression of the lesion after infection in the footpad was monitored for 12 weeks. Two groups of animals were formed to collect the plantar pad in the 4th and 12th week post-infection. Results: The lesion increased from the 3rd week onwards, in both groups, with a gradual decrease from the 10th week onwards in the CETP group compared to the WT group, showing a reduction in parasitism and an improvement in the healing process, a reduction in CD68+ cells, and an increase in CD163+ and CD206, characterizing a population of M2 macrophages. A reduction in ARG1+ cells and an increase in INOS+ cells were observed. During infection, the LP profile showed an increase in triglycerides in the VLDL fraction in the CETP group at 12 weeks. Gene expression revealed a decrease in the CD36 receptor in the CETP group at 12 weeks, correlating with healing and parasite reduction. In vitro, macrophages derived from bone marrow cells from CETP mice showed lower parasite load at 48 h and, a reduction in arginase activity at 4 h accompanied by increased NO production at 4 and 24 h compared to WT macrophages, corroborating the in vivo findings. Discussion: The data indicate that the presence of CETP plays an important role in resolving Leishmania (L.) amazonensis infection, reducing parasitism, and modulating the inflammatory response in controlling infection and tissue repair.

Thiourea-functionalized aminoglutethimide derivatives as anti-leishmanial agents.

Aim: We aim to develop new anti-leishmanial agents against Leishmania major and Leishmania tropica. Materials & methods: A total of 23 thiourea derivatives of (±)-aminoglutethimide were synthesized and evaluated for in vitro activity against promastigotes of L. major and L. tropica. Results & conclusion: The N-benzoyl analogue 7p was found potent (IC50 = 12.7 µM) against L. major and non toxic to normal cells. The docking studies, indicates that these inhibitors may target folate and glycolytic pathways of the parasite. The N-hexyl compound 7v was found strongly active against both species, and lacked cytotoxicity against normal cells, whereas compound 7r, with a 3,5-bis-(tri-fluoro-methyl)phenyl unit, was active against Leishmania, but was cytotoxic in nature. Compound 7v was thus identified as a hit for further studies.

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Mortality due to visceral leishmaniasis in Brazil by municipalities, 2001-2018: a spatial-temporal analysis of estimates from the Global Burden of Disease study.

OBJECTIVES: In the American regions, Brazil accounts for 97% of visceral leishmaniasis (VL) cases, with a case fatality rate of approximately 10%. This study aimed to investigate the VL mortality distribution in Brazil and identify high-priority and high-risk areas for intervention strategies. STUDY DESIGN: This was an ecological study that analysed the spatial-temporal patterns of VL mortality in Brazilian municipalities. METHODS: Age-standardised VL mortality rates from the Global Burden of Disease study from 2001 to 2018 were used. The distribution of mortality in the municipalities was assessed, and subsequently the Local Index of Spatial Autocorrelation (LISA) analysis was conducted to identify contiguous areas with high mortality rates. Scan analysis identified clusters of high spatial-temporal risks. RESULTS: The highest mortality rates and clusters were in municipalities located in the Northeast region and in the states of Tocantins and Roraima (North region), Mato Grosso do Sul (Central-West region), and Minas Gerais (Southeast region). According to LISA, there was an increase in the number of municipalities classified as high priority from the first 3-year period (n = 434) to the last 3-year period (n = 644). The spatio-temporal analysis identified 21 high-risk clusters for VL mortality. CONCLUSION: Areas with a high risk of VL mortality should prioritise preventing transmission, invest in early diagnosis and treatment, and promote the training of healthcare professionals.

The role of Nrf2 signaling in parasitic diseases and its therapeutic potential.

In response to invading parasites, one of the principal arms of innate immunity is oxidative stress, caused by reactive oxygen species (ROS). However, oxidative stresses play dual functions in the disease, whereby free radicals promote pathogen removal, but they can also trigger inflammation, resulting in tissue injuries. A growing body of evidence has strongly supported the notion that nuclear factor erythroid 2-related factor 2 (NRF) signaling is one of the main antioxidant pathways to combat this oxidative burst against parasites. Given the important role of NRF2 in oxidative stress, in this review, we investigate the activation mechanism of the NRF2 antioxidant pathway in different parasitic diseases, such as malaria, leishmaniasis, trypanosomiasis, toxoplasmosis, schistosomiasis, entamoebiasis, and trichinosis.

Incidence of cutaneous Leishmaniasis in humans during the COVID-19 pandemic in Baluchistan Province, Pakistan.

INTRODUCTION: Cutaneous leishmaniasis (CL) is one of the neglected tropical diseases that affects impoverished communities throughout the world. In Pakistan CL is an endemic disease. AIMS AND OBJECTIVES: This study aimed to determine the incidence of CL infection in the Baluchistan province of Pakistan from January 2020 to March 2022 during the COVID-19 pandemic. METHODOLOGY: A total of 1047 clinically suspected cases of CL from Bolan Medical College Hospital, Quetta, were followed up in the study. The data regarding the epidemiological characterstics, pathological information, and treatment of patients was collected. RESULTS: Out of 1047 probable cases of CL, 594 (56.73%) cases were found to be positive for CL. Females had the highest infection rate, with the majority of reported cases being in the 0-9-year age group. Most CL cases were reported in April in the year 2020, with a few cases reported in June. But in the year 2021, the highest number of cases were reported in December. The number of overall cases has gradually increased in the year 2022, most likely because of the reduction in COVID-19 pandemic restrictions. The p value for the positive as compared to suspected cases in the years 2020, 2021, and 2022 was calculated as 0.8925, 0.8763, and 0.8535 respectively. CONCLUSIONS: Further epidemiological studies and health education campaigns are recommended to increase public awareness. It is strongly advised that local, provincial, and national health authorities establish and maintain effective leishmaniasis surveillance systems to promptly identify disease outbreaks and implement timely control measures.

Histopathological findings and diagnosis of cutaneous leishmaniasis, confirmed by PCR, in an endemic region of Brazil.

INTRODUCTION: Diagnosis of cutaneous leishmaniasis (CL) is difficult, and the correct use of histopathological criteria can be useful in clinical practice. The present study evaluates the association between histopathological findings and the results of polymerase chain reaction (PCR) in clinically suspected cases of CL. METHODOLOGY: Skin samples were received in a laboratory from an endemic region of Brazil for over nine years. Associations were analyzed by means of the Chi square test with a 5% level of significance. RESULTS: Of the 222 examined samples, 190 (85.6%) tested positive by PCR. All 25 cases identified by microscopic examination also tested positive by PCR. Except for the more intense inflammatory infiltrate, all other evaluated histological variables (ulceration, epidermal hyperplasia, hyperkeratosis, presence of granuloma, neutrophils, histiocytes, lymphocytes, plasmocytes, and necrosis) were not significantly associated with PCR positivity. CONCLUSIONS: The intensity of the inflammatory infiltrate is a good indicator of the occurrence of CL. Histopathological aspects are useful to increase the predictive values of CL diagnoses, but PCR is still necessary to confirm or exclude the disease.

Prevalence of hepatitis B and C virus infections among visceral leishmaniasis patients: a systematic review and meta-analysis.

Background: Visceral leishmaniasis (VL) patients are at high risk of acquiring hepatitis B virus (HBV) and hepatitis C virus (HCV) infections during multiple injections and the anti-leishmanial treatment possesses a potential hepatotoxic effect. This systematic review and meta-analysis determined the pooled prevalence of HBV and HCV infections in VL patients. Methods: This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO), with the assigned number CRD42024516889, and conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A literature search was performed using PubMed, Medline, EMBASE, Google Scholar, Web of Science, and Science Direct databases. Data were extracted using Microsoft Excel and analyzed using STATA version 11.0 software. A random-effects model was used to estimate the pooled effect size of outcome variables across studies with a 95% confidence interval and was displayed in a forest plot. The I 2 statistic was used to check for heterogeneity. The presence of publication bias was determined using a funnel plot and Egger's test with a p value <0.05 evidence of statistically significant bias. Results: Among 216 retrieved records, seven studies were eligible for systematic review and meta-analysis. A total of 937 VL patients were examined, revealing that 105 and 93 were infected with HBV and HCV, respectively. The pooled prevalence of HBV was 16.15% (95% CI: -4.10 to 36.39), with a significant heterogeneity (I 2 = 91.4%, p < 0.001). The combined prevalence of HCV was 13.74% (95% CI: 1.32-26.16, I 2 = 71.6%, p = 0.003). The funnel plot (symmetry), and Egger's test in both HBV (p value = 0.650) and HCV (p value = 0.841) revealed no publication bias. In subgroup analysis, high HBV and HCV prevalence was detected in Sudan; 20.64% (95% CI: -13.60 to 54.88) and India; 18.26% (95% CI: -0.40 to 36.92%), respectively. Conclusion: This study revealed a high prevalence of both HBV and HCV infections in VL patients. In subgroup analysis, the prevalence of HBV and HCV was high in Sudan and India, respectively. Therefore, screening of VL patients for HBV and HCV, vaccination of VL patients in endemic regions, and collaboration between kala-azar and hepatitis elimination programs are required. Systematic review registration: https://www.crd.york.ac.uk/prospero/export_details_pdf.php#page=1.00&gsr=0, identifier: CRD42024516889.

Deciphering the intricate dynamics of inflammasome regulation in visceral and post-kala-azar dermal leishmaniasis: A meta-analysis of consistencies.

Post Kala-azar dermal leishmaniasis (PKDL) arises as a significant dermal sequel following Visceral leishmaniasis (VL) caused by protozoan parasite Leishmania donovani (LD). PKDL acts as a significant constrain for VL elimination serving as a crucial reservoir for LD. PKDL patients exhibit depigmented macular and papular lesions on their skin, which results in social discrimination due to loss of natural skin color. Inflammatory reactions, prevalent in both VL and PKDL, potentially lead to tissue damage in areas harboring the parasite. Disruption of the immune-inflammasomal network not only facilitates LD persistence but also leads to the skin hypopigmentation seen in PKDL, impacting social well-being. Activation of inflammasomal markers like STAT1, NLRP1, NLRP3, AIM2, CASP11, and NLRP12 have been identified as a common host-defense mechanism across various Leishmania infections. Conversely, Leishmania modulates inflammasome activation to sustain its presence within the host. Nevertheless, in specific instances of Leishmania infection, inflammasome activation can worsen disease pathology by promoting parasite proliferation and persistence. This study encompasses recent transcriptomic analyses conducted between 2016 and 2023 on human and murine subjects afflicted with VL/PKDL, elucidating significant alterations in inflammasomal markers in both conditions. It offers a comprehensive understanding how these markers contribute in disease progression, drawing upon available literature for logical analysis. Furthermore, our analysis identifies validated miRNA network that could potentially disrupt this crucial immune-inflammasomal network, thereby offering a plausible explanation on how secreted LD-factors could enable membrane-bound LD, isolated from the host cytoplasm, to modulate cytoplasmic inflammasomal markers. Insights from this study could guide the development of host-directed therapeutics to impede transmission and address hypopigmentation, thereby mitigating the social stigma associated with PKDL.

Targeting Leishmania Promastigotes and Amastigotes Forms through Amino Acids and Peptides: A Promising Therapeutic Strategy.

Millions of people worldwide are affected by leishmaniasis, caused by the Leishmania parasite. Effective treatment is challenging due to the biological complexity of the parasite, drug toxicity, and increasing resistance to conventional drugs. To combat this disease, the development of specific strategies to target and selectively eliminate the parasite is crucial. This Review highlights the importance of amino acids in the developmental stages of Leishmania as a factor determining whether the infection progresses or is suppressed. It also explores the use of peptides as alternatives in parasite control and the development of novel targeted treatments. While these strategies show promise for more effective and targeted treatment, further studies to address the remaining challenges are imperative.

Nicotinamide mitigates visceral leishmaniasis by regulating inflammatory response and enhancing lipid metabolism.

BACKGROUND: Currently, treatment regimens for visceral leishmaniasis (VL) are limited because of the presence of numerous adverse effects. Nicotinamide, a readily available and cost-effective vitamin, has been widely acknowledged for its safety profile. Several studies have demonstrated the anti-leishmanial effects of nicotinamide in vitro. However, the potential role of nicotinamide in Leishmania infection in vivo remains elusive. METHODS: In this study, we assessed the efficacy of nicotinamide as a therapeutic intervention for VL caused by Leishmania infantum in an experimental mouse model and investigated its underlying molecular mechanisms. The potential molecular mechanism was explored through cytokine analysis, examination of spleen lymphocyte subsets, liver RNA-seq analysis, and pathway validation. RESULTS: Compared to the infection group, the group treated with nicotinamide demonstrated significant amelioration of hepatosplenomegaly and recovery from liver pathological damage. The NAM group exhibited parasite reduction rates of 79.7% in the liver and 86.7% in the spleen, respectively. Nicotinamide treatment significantly reduced the activation of excessive immune response in infected mice, thereby mitigating hepatosplenomegaly and injury. Furthermore, nicotinamide treatment enhanced fatty acid ß-oxidation by upregulating key enzymes to maintain lipid homeostasis. CONCLUSIONS: Our findings provide initial evidence supporting the safety and therapeutic efficacy of nicotinamide in the treatment of Leishmania infection in BALB/c mice, suggesting its potential as a viable drug for VL.

Differences in the Cellular Immune Response during and after Treatment of Sudanese Patients with Post-kala-azar Dermal Leishmaniasis, and Possible Implications for Outcome.

BACKGROUND: The host cellular immune response associated with two treatments for post-kala-azar dermal leishmaniasis (PKDL) - paromomycin plus miltefosine (Arm 1), and liposomal amphotericin B plus miltefosine (Arm 2) - was examined in Sudanese patients before treatment (D0), at the end of treatment (D42), and during the post-treatment period (D180). METHODS: Whole blood samples were stimulated with soluble Leishmania antigen for 24 h (whole blood assay [WBA]) and the concentrations of Th1/Th2/Th17-associated cytokines, IP-10, PDL-1 and granzyme B were determined. RESULTS: The Arm 1 treatment (98.2% cure rate) induced a Th1/Th2/Th17 response, while the Arm 2 treatment (80% cure rate) induced a Th1/Th2 response. Five Arm 2 patients relapsed and showed lower IFN-γ, TNF and IL-1ß concentrations at D0 than non-relapsers in this Arm. In patients with low-IFN-γ-production at D0, Arm 1 treatment led to a better host immune response and clinical outcome than Arm 2 treatment. CONCLUSIONS: A Th1/Th2/Th17 response was associated with a higher cure rate. Patients with low IFN-γ, TNF and IL-1ß before treatment are more likely to relapse if they undergo Arm 2-type treatment. Determining IFN-γ, TNF and IL-10 levels prior to treatment could help predict patients at higher risk of relapse/recovery from PKDL. TRIAL REGISTRATION: ClinicalTrials.gov NCT03399955, Registered 17 January 2018, https://clinicaltrials.gov/study/ NCT03399955.

Proteome profiling of cutaneous leishmaniasis lesions due to dermotropic Leishmania donovani in Sri Lanka.

BACKGROUND: Characterization of the host response in cutaneous leishmaniasis (CL) through proteome profiling has gained limited insights into leishmaniasis research compared to that of the parasite. The primary objective of this study was to comprehensively analyze the proteomic profile of the skin lesions tissues in patients with CL, by mass spectrometry, and subsequent validation of these findings through immunohistochemical methods. METHODS: Eight lesion specimens from leishmaniasis-confirmed patients and eight control skin biopsies were processed for proteomic profiling by mass spectrometry. Formalin-fixed paraffin-embedded lesion specimens from thirty patients and six control skin specimens were used for Immunohistochemistry (IHC) staining. Statistical analyses were carried out using SPSS software. The chi-square test was used to assess the association between the degree of staining for each marker and the clinical and pathological features. RESULTS: Sixty-seven proteins exhibited significant differential expression between tissues of CL lesions and healthy controls (p < 0.01), representing numerous enriched biological processes within the lesion tissue, as evident by both the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Reactome databases. Among these, the integrated endoplasmic reticulum stress response (IERSR) emerges as a pathway characterized by the up-regulated proteins in CL tissues compared to healthy skin. Expression of endoplasmic reticulum (ER) stress sensors, inositol-requiring enzyme-1 (IRE1), protein kinase RNA-like ER kinase (PERK) and activating transcription factor 6 (ATF6) in lesion tissue was validated by immunohistochemistry. CONCLUSIONS: In conclusion, proteomic profiling of skin lesions carried out as a discovery phase study revealed a multitude of probable immunological and pathological mechanisms operating in patients with CL in Sri Lanka, which needs to be further elaborated using more in-depth and targeted investigations. Further research exploring the intricate interplay between ER stress and CL pathophysiology may offer promising avenues for the development of novel diagnostic tools and therapeutic strategies in combating this disease.

A Comprehensive Review of the Situation of Visceral Leishmaniasis Vectors in Iran.

Background: This study's major aim is to investigate the situation of visceral leishmaniasis vectors, with a focus on their distribution and relationships to the disease in Iran and some other old-world nations. Methods: The terms Iran and the Old World, along with the keywords sand flies, vectors, visceral leishmaniasis, distribution, and Phlebotomus, were searched in electronic databases from 1930 to 2018, including Pub-Med, Web of Science, Google Scholar, and MEDLINE. Results: According to the findings, Phlebotomus tobbi was a mountain species, but it was also found in the plains, rodent nests, and rock crevices. This species was considered to be one of the vectors of visceral leishmaniasis in Iran. Phlebotomus kandelakii has been caught in Afghanistan, Iran, Lebanon, Turkey and Georgia. In Iran, the first infection of Phlebotomus kandelakii and Ph. perfiliewi transcaucasicus with Leishmania infantum were reported in northwest of Iran. Phlebotomus major was one of the complex sand flies, and its members include Ph. major (India, Nepal, and Pakistan), Ph. neglectus (Southern Europe, Crimea and Iran), Ph. syriacus (Southwest Asia, Caucasus), Ph. notus (Afghanistan and Iran), Ph. wenyoni (Iran and Iraq), and Ph. wui (China). The first natural infection of Ph. alexandri with Leishmania infantum was reported in 2006 in endemic foci of visceral leishmaniasis in Fars Province, southern Iran. Conclusion: The findings of this project suggest that sand fly species of the subgenus Larrousisus play a key role in the transmission of all types of visceral leishmaniasis in Iran.

Assessing Survival of Transgenic Bacteria, Serratia AS1 and Enterobacter cloacae, in Sugar Bait, White Saxaul Plant (Haloxylon persicum) and Rodent Barrow's Soil, A Contained-Field Study for Paratransgenesis Approach.

Background: The viability and persistence of engineered bacterium candidates in field conditions is one of the considerable challenges in the paratransgenesis approach to fighting vector-borne diseases. Methods: In this study two engineered bacterium candidates to produce paratransgenic sand flies, Serratia AS1 and Enterobacter cloacae expressing m-Cherry fluorescent were applied on the leaves of the white saxaul plant (Haloxylon persicum), sugar bait, and rodent burrow soil and their persistent time was tested in desert condition, Matin Abad County, Isfahan, August 2022. A PBS suspension of 109 cells/ml was used for sugar bait, spraying on plant leaves (∼10 cm2) and 10 cm2 of rodent burrow soil. Sand fly samples were taken daily and were plated on LB Agar and the fluorescent cells were counted after 24 hours. Results: Time course in general caused a decrease in the number of bacteria for both strains. The two strains were persistent in sugar bait and on plant leaves for four days and on soil for two days. Although there were slight differences between the number of the bacteria in sugar baits, which was not significant (P< 0.05). The number of E. cloacae surviving on plant and in soil were significantly (P< 0.0001 and P= 0.046) higher than Serratia AS1. Conclusion: This study shows that plants or sugar bait are useful routes for delivery of the transformed bacteria for the paratransgenesis approach, although, the bacteria ought to be sprayed on plants or sugar baits should be replaced with new ones in four days intervals.

A Case Series of 36 Patients Treated for Old World Cutaneous leishmaniasis.

Background: Cutaneous leishmaniasis is endemic in Iran. Objective: We sought to investigate the therapeutic outcomes and complications of treatment in patients with cutaneous leishmaniasis. Methods: This case series enrolled patients with smear-proven cutaneous leishmaniasis who visited our center in Iran from 2018 to 2019. Results: In total, 36 patients were treated with intralesional meglumine antimoniate, intramuscular meglumine antimoniate, sodium stibogluconate, and amphotericin B. Overall, this treatment was effective in 81.8 percent of patients. Relapse and treatment failure occurred in 6.1 percent and 12.1 percent of patients, respectively. Treatment with intralesional meglumine antimoniate, intramuscular meglumine antimoniate, sodium stibogluconate, and amphotericin B yielded a clearance rate of 80.8 percent, 92.3 percent, 75 percent, and 85.7 percent, respectively. Clearance was associated with a shorter time interval between injections of intralesional meglumine antimoniate (p=0.006) and relapse was associated with a longer time interval between injections (p=0.018). The average number of side effects per patient for intralesional meglumine antimoniate, sodium stibogluconate, intramuscular meglumine antimoniate, and amphotericin B was 0.62, 1.4, 1.6, and 2.8, respectively. The most common side effect of intralesional meglumine antimoniate, intramuscular meglumine antimoniate, and amphotericin B was local pain, arthralgia, and hypokalemia, respectively. Limitations: Low sample size was the limitation of this study. Conclusion: The cure rate of intramuscular meglumine antimoniate was higher than amphotericin B, which was higher than the cure rate of sodium stibogluconate. In patients treated with intralesional meglumine antimoniate, reducing the time interval between injections increased the clearance rate and decreased the rate of relapse.

Innovating Leishmaniasis Treatment: A Critical Chemist's Review of Inorganic Nanomaterials.

Leishmaniasis, a critical Neglected Tropical Disease caused by Leishmania protozoa, represents a significant global health risk, particularly in resource-limited regions. Conventional treatments are effective but suffer from serious limitations, such as toxicity, prolonged treatment courses, and rising drug resistance. Herein, we highlight the potential of inorganic nanomaterials as an innovative approach to enhance Leishmaniasis therapy, aligning with the One Health concept by considering these treatments' environmental, veterinary, and public health impacts. By leveraging the adjustable properties of these nanomaterials─including size, shape, and surface charge, tailored treatments for various diseases can be developed that are less harmful to the environment and nontarget species. We review recent advances in metal-, oxide-, and carbon-based nanomaterials for combating Leishmaniasis, examining their mechanisms of action and their dual use as standalone treatments or drug delivery systems. Our analysis highlights a promising yet underexplored frontier in employing these materials for more holistic and effective disease management.

Bioactivity of synthetic peptides from Ecuadorian frog skin secretions against Leishmania mexicana, Plasmodium falciparum, and Trypanosoma cruzi.

Chagas disease, leishmaniasis, and malaria are major parasitic diseases disproportionately affecting the underprivileged population in developing nations. Finding new, alternative anti-parasitic compounds to treat these diseases is crucial because of the limited number of options currently available, the side effects they cause, the need for long treatment courses, and the emergence of drug-resistant parasites. Anti-microbial peptides (AMPs) derived from amphibian skin secretions are small bioactive molecules capable of lysing the cell membrane of pathogens while having low toxicity against human cells. Here, we report the anti-parasitic activity of five AMPs derived from skin secretions of three Ecuadorian frogs: cruzioseptin-1, cruzioseptin-4 (CZS-4), and cruzioseptin-16 from Cruziohyla calcarifer; dermaseptin-SP2 from Agalychnis spurrelli; and pictuseptin-1 from Boana picturata. These five AMPs were chemically synthesized. Initially, the hemolytic activity of CZS-4 and its minimal inhibitory concentration against Escherichia coli, Staphylococcus aureus, and Candida albicans were determined. Subsequently, the cytotoxicity of the synthetic AMPs against mammalian cells and their anti-parasitic activity against Leishmania mexicana promastigotes, erythrocytic stages of Plasmodium falciparum and mammalian stages of Trypanosoma cruzi were evaluated in vitro. The five AMPs displayed activity against the pathogens studied, with different levels of cytotoxicity against mammalian cells. In silico molecular docking analysis suggests this bioactivity may occur via pore formation in the plasma membrane, resulting in microbial lysis. CZS-4 displayed anti-bacterial, anti-fungal, and anti-parasitic activities with low cytotoxicity against mammalian cells. Further studies about this promising AMP are required to gain a better understanding of its activity.IMPORTANCEChagas disease, malaria, and leishmaniasis are major tropical diseases that cause extensive morbidity and mortality, for which available treatment options are unsatisfactory because of limited efficacy and side effects. Frog skin secretions contain molecules with anti-microbial properties known as anti-microbial peptides. We synthesized five peptides derived from the skin secretions of different species of tropical frogs and tested them against cultures of the causative agents of these three diseases, parasites known as Trypanosoma cruzi, Plasmodium falciparum, and Leishmania mexicana. All the different synthetic peptides studied showed activity against one of more of the parasites. Peptide cruzioseptin-4 is of special interest since it displayed intense activity against parasites while being innocuous against cultured mammalian cells, which indicates it does not simply hold general toxic properties; rather, its activity is specific against the parasites.

Identification of Lutzomyia longipalpis' using MALDI-TOF peptide/protein profiles.

Sand flies are vectors of great public health importance, since they constitute a group of hematophagous insects responsible for etiological agents transmission of zoonotic diseases such a visceral leishmaniasis. In face of the expansion of these diseases, efficient control strategies are needed which depend on comprehending the sand fly eco-epidemiology. In this regard, MALDI-TOF mass spectrometry has been used for bacteria, fungi and yeast detection studies through peptide/protein profiles. However, little is known about interference of biological factors associated with vector ecology, such as blood meal preferences and even sand fly age on the peptide/protein profiles. Thus, the present study aimed to evaluate the differences in peptide/protein profiles of the sand fly Lutzomyia longipalpis, by means of MALDI-TOF, due to the sand fly's age, sex, blood meal source and Leishmania infantum infection. Sample preparation was made removing both head and last abdomen segments keeping the thorax, its appendices and the rest of the abdomen. Five specimens per pool were used to obtain peptide/protein extract of which 1 µL solution was deposited over 1 µL MALDI matrix dried. Characteristic spectra were analyzed using principal coordinate analysis as well as indicator species analysis to discriminate differences in sand flies's peptide/protein profile by sex, age, blood meal source and L. infantum infection. The results show that the evaluated variables produced distinct peptide/protein profiles, demonstrated by the identification of specific diagnostic ions. It was found that the interference of biological factors should be taken into account when using the MALDI-TOF analysis of sand fly species identification and eco-epidemiological applications in field studies. Based on our results, we believe that it is possible to identify infected specimens and the source of blood meal in a collection of wild sand flies, serving to measure infectivity and understand the dynamics of the vector's transmission chain. Our results may be useful for epidemiological studies that look at the ecology of sand flies and leishmaniasis, as well as for raising awareness of biological characteristics' impact on peptide/protein profiles in sand fly species identification.

The Parasitemia has Contributed to the Severity of Cases of Visceral Leishmaniasis.

Visceral leishmaniasis (VL) occurs due to the evolution, virulence, and adaptation of Leishmania, vector biology, host immune system evasion, and reservoir hosts. Parasitemia can be involved as a warning regarding the clinical severity of VL The present study aims to evaluate the relationship between parasitemia and the prognosis of individuals with VL. Blood and bone marrow samples from individuals with VL were analyzed to identify parasite and quantify or measure parasite burden. Individuals were classified in the clinical score model of risk of death by disease proposed by Coura-Vital et al. (PLoS Negl Trop Dis 8(12): e33742014, 2014). 39/74 individuals presented a better prognosis, and 35/74 individuals presented a worse prognosis. HIV + VL co-infection was present in 32 individuals, of which 12 were considered severe. The group aged 51 to 64 was classified as severe, with a decrease in leukocytes (p-value 0.0295) and neutrophils (p-value 0.0476). L. infantum DNA was identified in blood and bone marrow, in 69 individuals, and not detected in 5 individuals. The quantification of the parasite showed greater parasitemia in bone marrow (P = 0.0003) with an average of 4.70 × 104 Leishmanias/mL about blood, with 0.29 × 104 Leishmanias/mL. Individuals in the age group aged 51 to 64 co-infected with HIV + VL had higher parasitemia (p-value 0.0150) with 2.44 × 104 Leishmanias/mL in blood and bone marrow than in the group aged 20 to 50. Parasitemia, measured by molecular biology in blood and bone marrow, was related to the worst clinical prognosis of VL in the age group aged 51 to 64.

Evaluation of Nanonanoliposomal Curcumin on Cutaneous Leishmaniasis Skin Lesions Caused by Leishmania major in BALB/c Mice.

Background: Curcumin is an extract of rhizome turmeric (diferuloylmethane), with antioxidant, anti-inflammatory, antimicrobial, and anti-parasitic properties, which making it a potential candidate for the treatment of leishmaniasis. The aim of the presented study was to evaluate curcumin as possible candidate for treatment of cutaneous leishmaniasis. Methods: We investigated the physicochemical properties and anti-leishmanial effects of nanoliposomal curcumin (40, 80, and 120 µM) in Leishmania major (MRHO/IR/75/ER) infected BALB/c mice at the faculty of Veterinary Medicinem University of Tehran, Iran. For this aim, L. major promastigotes (MHROM/IR/75/ER) at stationary phase (2×106) were inoculated sub-cutaneously into the upper area of the tail in BALB/c mice (six groups, n= 10 per group). For evaluation of nanoliposomal curcumin, the zeta potential, particle size and stability of nanoliposomal curcumin was determined. Furthermore, the anti-leishmanial effects of nanoliposomal curcumin formulation on the lesion sizes was determined and the parasite burden in the leishmania induced lesion was performed using semi quantitative PCR. Results: Treatment of L. major infected BALB/c mice with nanoliposomal curcumin led to a reduction in the kinetic of the skin lesion size development. The semi quantitative PCR analysis of DNA extracted from the lesions showed reduction of parasite burden. The most effective treatment could be found in 80 µM nanoliposomal curcumin. Treatment with Glucantime, as a positive control, also showed a nearly similar effect compared to the effect of 80 µM nanoliposomal curcumin. Conclusion: Nanoliposomal curcumin could be considered as a potential drug against cutaneous leishmaniasis caused by L. major in susceptible animal models.