Experimental parasitology最新文献

{"title":"Exposure to Bisphenol-A increases susceptibility to Trypanosoma cruzi infection","authors":"Aracely López-Monteon ,&nbsp;Anahí Sosa-Arróniz ,&nbsp;Mariana Colorado-Zuñiga ,&nbsp;Enrique Méndez-Bolaina ,&nbsp;Jesús Torres-Montero ,&nbsp;Angel Ramos-Ligonio","doi":"10.1016/j.exppara.2025.108990","DOIUrl":"10.1016/j.exppara.2025.108990","url":null,"abstract":"<div><div>Bisphenol-A (BPA), an endocrine disruptor, disrupts hormonal and chemical signaling within the body, negatively impacting health. One target of this disruption is the immune system. While BPA has been implicated in increased susceptibility to some pathogen infections, its effects on protozoan parasite infections remain understudied. This work evaluated the effect of BPA exposure on experimental <em>Trypanosoma cruzi</em> parasitemia in BALB/c mice.</div><div>Parasitemia was evaluated in BALB/c mice by counting parasites in a Neubauer chamber. Additionally, ELISA assays were used to identify the presence of antibodies, cytokine gene expression was analyzed by RT-PCR, and liver marker levels were quantified using enzymatic kinetic methods. Both pre- and post-exposure to BPA increased parasitemia during <em>T. cruzi</em> infection and decreased levels of IgG1, IgG2a, and IgG2b isotypes. Furthermore, BPA modulated the expression of pro-inflammatory cytokines in response to infection. In addition, all mice exposed to BPA showed alterations in liver enzymes compared to the control group. These results demonstrate that the immune system during critical periods of <em>T. cruzi</em> infection is highly sensitive to BPA exposure, increasing susceptibility to the parasite.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108990"},"PeriodicalIF":1.4,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144711395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational design of inhibitory peptides and an mRNA-Based multi-epitope vaccine targeting the MIC3 protein of Eimeria tenella","authors":"Roohollah Fattahi ,&nbsp;Ali Shivaee ,&nbsp;Maryam Bahraminia ,&nbsp;Nazanin Omidi ,&nbsp;Behrooz Sadeghi Kalani","doi":"10.1016/j.exppara.2025.108986","DOIUrl":"10.1016/j.exppara.2025.108986","url":null,"abstract":"<div><div>This study addresses coccidiosis, a prevalent disease causing significant economic losses, and focuses on the EtMIC3 protein due to its critical role in Eimeria <em>tenella</em> pathogenesis. Our goal is to develop innovative therapeutic and preventive strategies leveraging the potential of the EtMIC3 protein.</div><div>In this investigation, we evaluate the interaction of the EtMIC3 protein with its receptors, develop inhibitory peptides, and select epitopes from EtMIC3 using immunoinformatic tools. We assess the presentation of these epitopes to immune cells, model a multi-epitope protein, predict the mRNA structure, and evaluate the immune response to the newly designed vaccine.</div><div>Docking studies indicated that the predicted peptides exhibited a strong affinity for binding to the EtMIC3 protein, with identified epitopes residing within the antigen-binding groove of their respective MHC alleles. The developed vaccine demonstrated stability, non-toxicity, and non-allergenicity, effectively eliciting responses from both the innate and adaptive immune systems.</div><div>These findings suggest that the EtMIC3 protein is a promising target for both the inhibition of <em>E. tenella</em> and vaccine development. However, further validation through experimental and clinical studies is essential to corroborate these computational predictions.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108986"},"PeriodicalIF":1.4,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144625682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Furan derivative affects the cell division and mitochondrial integrity of tachyzoites of Toxoplasma gondii","authors":"Juliana de Araujo Portes ,&nbsp;Anushree Achari ,&nbsp;Jayaraman Vinayagam ,&nbsp;Pinaki Bhattacharjee ,&nbsp;Sourav Chatterjee ,&nbsp;Parasuraman Jaisankar ,&nbsp;Wanderley de Souza","doi":"10.1016/j.exppara.2025.108988","DOIUrl":"10.1016/j.exppara.2025.108988","url":null,"abstract":"<div><div><em>Toxoplasma gondii</em> is an obligate intracellular protozoan, the causative agent of toxoplasmosis. The current treatment against toxoplasmosis is based on the combination of sulfadiazine and pyrimethamine, which are toxic and unable to clear the infection. Due to the need for new active drugs against <em>T. gondii</em>, we have described here the effects of Furan derivatives on <em>T. gondii in vitro</em>. They were previously used with relevant activity against <em>Leishmania amazonensis</em> and <em>Trypanosoma cruzi.</em> The <em>anti-Toxoplasma</em> effects of the furan derivatives were evaluated using tachyzoites of <em>T. gondii</em> from RH strain and as host cells the human foreskin fibroblast (HFF) and the epithelial lineage from Macaca mulatta LLC-MK2. High-content screening and other microscopy techniques were employed to analyze the infected cells after incubation in the presence of the compounds tested. The most effective derivative was <strong>3g</strong>, presenting a 50 % inhibitory concentration (IC50) of 4.3 μM after 48 h of incubation. The 50 % cytotoxic concentration (CC50) in the host cells was 50 μM after a 72-h treatment. The ultrastructural analysis showed that after treatment the parasites presented cytoplasmic emptying, mitochondrial swelling, and interference with cell division<strong>.</strong> It was revealed by TUNEL assay that the parasites dyed in part due to an apoptosis-like cell death. These findings suggest that the furan derivative <strong>3g</strong> is a potential candidate for further studies <em>in vivo</em> to find alternative drugs to treat <em>T. gondii</em> infections.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108988"},"PeriodicalIF":1.4,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144604918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of a common intestinal helminth on fecal corticosterone metabolite concentrations of Northern Bobwhite (Colinus virginianus)","authors":"Jeremiah Leach ,&nbsp;Hannah N. Suber ,&nbsp;Regan Rivera ,&nbsp;James G. Surles ,&nbsp;Ronald J. Kendall","doi":"10.1016/j.exppara.2025.108987","DOIUrl":"10.1016/j.exppara.2025.108987","url":null,"abstract":"<div><div>It has been shown in several wild populations that helminths can affect survival and reproduction in avian hosts, even at moderate intensities. <em>Colinus virginianus</em> (Northern bobwhite) is a North American grassland game bird with a wide geographic range, including the southeastern and midwestern U.S. In the arid and semi-arid regions of its range, infections by the cecal worm <em>Aulonocephalus pennula</em> are common and frequently occur at high intensities. The objective of this study was to estimate changes in fecal corticosterone concentrations (FCMs) of <em>C. virginianus</em> as a function of <em>A. pennula</em> infection intensity. Wild <em>C. virginianus</em> were trapped in western Oklahoma using double-funnel traps in May and June of 2022 and 2023. We estimated <em>A. pennula</em> burden by extracting DNA from cloacal swabs and used a quantitative polymerase chain reaction (qPCR). We then estimated FCMs from <em>C. virginianus</em> fecal samples that had been defecated within 10 min of collecting the cloacal swab and FCM concentrations using an enzyme immunoassay recently validated for <em>C. virginianus</em>. The results show a significant increase in FCM concentrations with increasing <em>A. pennula</em> intensity. This study concludes that <em>A. pennula</em> influences the hypothalamus-pituitary-adrenal (HPA) axis by increasing FCM concentrations, and likely the concentration of circulating free corticosterone. Thus, there is a physiological mechanism by which <em>A. pennula</em> could impact both reproduction and survival of <em>C. virginianus</em>.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108987"},"PeriodicalIF":1.4,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transfection of bovine cells with synthetic mRNA to induce expression of functional antibodies against Tritrichomonas foetus surface antigen TF1.17","authors":"Merrilee Thoresen ,&nbsp;Daryll Vanover ,&nbsp;E. Heath King ,&nbsp;Darcie Sidelinger ,&nbsp;Jean M. Feugang ,&nbsp;Hannah E. Peck ,&nbsp;Kenzie McAtee ,&nbsp;Philip J. Santangelo ,&nbsp;Amelia R. Woolums","doi":"10.1016/j.exppara.2025.108985","DOIUrl":"10.1016/j.exppara.2025.108985","url":null,"abstract":"<div><div>Bovine trichomonosis is caused by the urogenital parasite <em>Tritrichomonas foetus (T. foetus).</em> In the United States, approved therapies are lacking, and management is limited to culling infected bulls. Preputial therapy with synthetic mRNA could lead to effective new treatments. We developed synthetic mRNA encoding bovine IgG1 against two epitopes of the <em>T. foetus</em> cell surface antigen TF1.17 and used the mRNA to transfect bovine cells <em>in vitro</em>. Transfected cells expressed membrane anchored or secreted versions of the antibodies with a NanoLuciferase (NanoLuc) reporter molecule fused to each light chain. Luminescence in cells and supernatants collected 24 and 48 h post-transfection confirmed the production of anti-TF1.17 and was significantly higher than in non-transfected controls (p &lt; 0.05). Anti-TF1.17 bound to live parasites as indicated by significantly higher luminescence following treatment with 24 and 48 h post-transfection supernatants compared to transfection controls (p = 0.001). Treatment of <em>T. foetus</em> with concentrated anti-TF1.17 antibody decreased parasite viability. When <em>T</em>. <em>foetus</em> were added to mRNA transfected kidney cells 48 h post transfection, cytopathic effects of the parasites were reduced following 24 h of co-culture with cells producing anti-TF1.17 as compared to controls (p &lt; 0.05). To our knowledge, this is the first use of mRNA transfection of bovine cells to induce the expression of antibodies that can bind to <em>T. foetus</em>, decrease their viability and their cytopathic effects on host cells. This work forms the basis for the development of novel mRNA-mediated approaches to treat or prevent bovine trichomonosis.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108985"},"PeriodicalIF":1.4,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144559558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimalarial potentials, toxicological impacts, and gas chromatography-mass spectrometric analysis of ethanol extract of Spondias mombin Linn","authors":"Nicodemus Emeka Nwankwo ,&nbsp;Obiora Emmanuel Abonyi ,&nbsp;Emmanuel Henry Ezenabor ,&nbsp;Bartholomew Onyekachi Okolo","doi":"10.1016/j.exppara.2025.108984","DOIUrl":"10.1016/j.exppara.2025.108984","url":null,"abstract":"<div><div>Malaria remains a significant global health challenge, necessitating new treatment approaches. This study aimed to investigate the effects of ethanol extract from <em>Spondias mombin</em> leaves on parasitemia, hematological parameters, oxidative stress, liver and kidney function, and serum electrolyte levels in malaria-infected mice. The experimental mice were infected with <em>P. berghei</em> and treated with graded doses of <em>Spondias mombin</em> ethanol extract. Hematological parameters (RBC, WBC, platelet count, Hb, PCV), antioxidant enzyme activities (CAT, SOD, GPx), oxidative stress markers, liver function biomarkers (ALP, AST, ALT, total bilirubin), kidney function biomarkers (urea, creatinine, direct bilirubin), and electrolyte levels (Na⁺, K⁺, Cl⁻, HCO₃⁻) were measured. Different doses of the extract alongside the standard drug significantly inhibited parasite growth. The extract significantly improved hematological parameters and showed no significant effect on SOD activity. CAT activity increased at 100 mg/kg, while GPX activity was highest in controls and lowest at 200 mg/kg. MDA levels decreased significantly at 200 mg/kg. AST and ALP activities varied dose-dependently, reaching a peak at 200 mg/kg. ALT and total bilirubin levels remained stable. Direct bilirubin levels increased at 100 and 200 mg/kg, while urea and creatinine indicated renal stress at higher doses. Sodium and potassium levels decreased dose-dependently, with stable Cl⁻ and HCO₃⁻ levels. A total of 65 bioactive components were found following the results of the GC-MS analysis. Significant antioxidant and antimalarial properties are shown by this extract, and its steady electrolyte levels and low liver stress imply safety. To identify the precise antimalarial bioactive components and their modes of action, more investigation is required. Conclusively, ethanol extract from <em>Spondias mombin</em> shows promise as a malaria adjuvant treatment.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108984"},"PeriodicalIF":1.4,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144518744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Towards effective and efficient machine learning models for schistosomiasis diagnosis in microscopic images","authors":"Bruno Alberto Soares Oliveira ,&nbsp;Paulo Ricardo Silva Coelho ,&nbsp;João Marcelo Peixoto Moreira ,&nbsp;Marcos Antonio Alves ,&nbsp;Deborah Aparecida Negrão-Corrêa ,&nbsp;Stefan Michael Geiger ,&nbsp;Frederico Gadelha Guimarães","doi":"10.1016/j.exppara.2025.108967","DOIUrl":"10.1016/j.exppara.2025.108967","url":null,"abstract":"<div><div>Schistosomiasis is an infectious disease caused by the parasite <em>Schistosoma mansoni</em>, and it is a significant health concern in many underdeveloped tropical regions. The traditional method of diagnosing schistosomiasis involves fecal examinations under a microscope for parasite eggs, a process that is time consuming, error-prone, and requires specialized training. Artificial intelligence encompasses a broad range of techniques, including both machine learning and its subset, deep learning, which have been successful in solving such problems. Therefore, this study aimed to propose an automated solution that combines DL-based object detection methods with classical ML techniques and HOG feature extraction to identify <em>S. mansoni</em> eggs in images obtained using the Kato-Katz parasitological technique. A real database of 1100 images was created, processed, and annotated by three parasitologists. The proposed system achieved an Average Precision of 0.884 for an @[IoU = 0.50] using a Faster R-CNN method with ResNet-50 architecture over the best-annotated data, outperforming other detection models. Based on a threshold analysis, we suggest an integrated approach with a voting scheme of machine learning models to improve results in terms of false positives and false negatives. Comparative analysis with external data and a commercial tool confirmed that our approach offers promising results and applicability to assist health professionals in diagnosing schistosomiasis in public health systems, such as the Brazilian Unified Health System (SUS), potentially improving diagnosis speed and accuracy in endemic regions.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108967"},"PeriodicalIF":1.4,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144511669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring global trends in human toxoplasmosis seroprevalence by meta-analysis","authors":"Pinaki Prasad Sengupta,&nbsp;Siju Susan Jacob,&nbsp;Kuralayanapalya Puttahonnappa Suresh,&nbsp;Shinduja Rajamani,&nbsp;S Madhaba Maharana","doi":"10.1016/j.exppara.2025.108971","DOIUrl":"10.1016/j.exppara.2025.108971","url":null,"abstract":"<div><div>Understanding the global prevalence of infectious diseases is essential for effective public health strategies and resource allocation. Among foodborne diseases, toxoplasmosis—caused by <em>Toxoplasma gondii</em>—poses significant health risks, particularly for pregnant women and immunocompromised individuals. This study presents one of the most comprehensive systematic reviews and meta-analyses to date, synthesizing global seroprevalence estimates of human toxoplasmosis from 320 studies, covering 658,172 individuals across 113 countries and six continents, spanning the period from 1959 to 2020. A thorough literature search was conducted using databases including PubMed, ScienceDirect, and Google Scholar, applying rigorous inclusion criteria to ensure methodological consistency. The pooled global seroprevalence was estimated at 31 % (95 % CI: 28–34 %), with marked heterogeneity between studies (I² = 99.6 %). The highest prevalence was observed in Australia (54 %), South America (45 %), and Africa (42 %), while Asia reported the lowest (25 %). Country-wise, Brazil and Ghana had the highest prevalence (68 %), whereas Vietnam had the lowest (5 %). Temporal analysis revealed an upward trend, reaching 34 % during 2011–2020. Diagnostic methods significantly influenced prevalence estimates, with IFAT yielding the highest rate (41 %). Extensive subgroup analyses by region, time period, country, and diagnostic technique provided granular insights into seroprevalence patterns. While acknowledging limitations such as selection bias and diagnostic variability, this study offers an unparalleled synthesis of global data, filling critical knowledge gaps. The findings serve as an essential reference point for global public health planning, particularly in high-prevalence regions.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108971"},"PeriodicalIF":1.4,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144495416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Urine- and serum-based ELISA using a new recombinant chimeric protein to diagnose tegumentary and visceral leishmaniasis: a preliminary study","authors":"Raquel S.B. Câmara ,&nbsp;Ana L. Silva ,&nbsp;Camila S. Freitas ,&nbsp;Daniela P. Lage ,&nbsp;Nathália C. Galvani ,&nbsp;Ana T. Chaves ,&nbsp;Bárbara P.N. Assis ,&nbsp;Breno L. Pimenta ,&nbsp;Karolina O.M. Falcão ,&nbsp;Saulo S.G. Dias ,&nbsp;Maíza M. Rodrigues ,&nbsp;Grasiele S.V. Tavares ,&nbsp;Alexsandro S. Galdino ,&nbsp;Unaí Tupinambás ,&nbsp;Manoel O. da Costa Rocha ,&nbsp;Denise U. Gonçalves ,&nbsp;Miguel A. Chávez-Fumagalli ,&nbsp;Myron Christodoulides ,&nbsp;Ricardo A. Machado-de-Ávila ,&nbsp;Eduardo A.F. Coelho ,&nbsp;Isabela A.G. Pereira","doi":"10.1016/j.exppara.2025.108980","DOIUrl":"10.1016/j.exppara.2025.108980","url":null,"abstract":"<div><div>Laboratory diagnosis of leishmaniasis is hampered by the variable sensitivity and/or specificity of the tests. In the present study, we developed a new recombinant antigen based on a chimeric protein, called CHIMISA, which was composed of specific B-cell epitopes from <em>Leishmania</em> antigenic proteins recently identified in an immunoproteomics approach using sera samples from visceral leishmaniasis (VL) and VL/HIV co-infected patients. The protein was produced containing specific B-cell epitopes from four parasite proteins (SUZ41772.1, SUZ41881.1, AYU79515.1, and SUZ44007.1) and used as an antigen in ELISA with serum and urine samples for diagnosing VL, tegumentary leishmaniasis (TL), and VL/HIV co-infection. Paired serum and urine samples from healthy subjects and patients with other cross-reactive diseases were also used. The serum-based CHIMISA ELISA had 100 % sensitivity and 98.5 % specificity for diagnosing VL, TL and VL/HIV, with an area under the (AUC) value of 1.0. Soluble <em>Leishmania</em> Antigenic (SLA) extracts of <em>Leishmania (Viannia) braziliensis</em> and SLA of <em>Leishmania (Leishmania) infantum</em> were used as comparative antigens, and showed sensitivity values of 72.0 % and 44.0 %, respectively, and specificity values of 97.5 % and 98.1 %, respectively. The AUC values were 0.90 and 0.91, respectively. In the urine-based CHIMISA ELISA, sensitivity of 99.0 % and specificity of 98.1 % were reached, with an AUC of 0.99. SLA of <em>L. (V.) braziliensis</em> and SLA of <em>L. (L.) infantum</em> showed 65.6 % and 51.1 % sensitivity, respectively; and 96.9 % and 97.1 % specificity, respectively. The AUC values were 0.91 and 0.86, respectively. Although only a limited serological panel was used in this study, our preliminary data suggest that this new chimeric protein could be considered as a diagnostic candidate for VL, TL, and VL/HIV cases, using patient urine and serum.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108980"},"PeriodicalIF":1.4,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144365912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upregulation of nicotinamide/nicotinate mononucleotide adenylyl transferase increases resistance to oxidative stress and antimony in promastigotes of Leishmania braziliensis","authors":"Esteban León ,&nbsp;Milena Maya-Hoyos ,&nbsp;María H. Ramírez-Hernández ,&nbsp;Jair Téllez ,&nbsp;Luis E. Contreras R","doi":"10.1016/j.exppara.2025.108979","DOIUrl":"10.1016/j.exppara.2025.108979","url":null,"abstract":"<div><div>Leishmaniasis is a prevalent parasitic neglected disease caused by protozoans of the genus <em>Leishmania</em>. Currently, no vaccines are available for humans, and existing treatments are ineffective because of their toxicity and the emergence of drug-resistant strains. Consequently, it is crucial to identify new potential therapeutic targets, thereby facilitating the development of effective therapies. This study indicates a correlation between the upregulated biosynthesis of nicotinamide adenine dinucleotide (NAD) and the resistance to hydrogen peroxide (H₂O₂) and trivalent antimony exposure (Sb³⁺) in <em>L. braziliensis</em> promastigotes. CRISPR/Cas9 gene-editing of the nicotinamide/nicotinate mononucleotide adenylyl transferase in <em>L. braziliensis</em> (<em>Lbnmnat</em>), the key gene in the NAD biosynthetic pathway, allowed upregulation at both the mRNA and protein levels, as well as elevated NAD and NADP contents in the <em>Lbnmnat</em>-edited parasites. A single guide RNA template, directed against the 5′ end of the <em>Lbnmnat</em> and a donor DNA consisting of the <em>mCherry</em> reporter gene preceded by the 5’ UTR from the <em>Crithidia fasciculata</em> phosphoglycerate kinase (<em>CfPGKB</em>) were electroporated into <em>L. braziliensis</em> promastigotes that constitutively express the <em>Streptococcus pyogenes</em> Cas9 and T7 RNA polymerase. PCR analysis and DNA sequencing demonstrated the successful editing of the <em>Lbnmnat</em> gene. Importantly, dose-dependent oxidative stress susceptibility assays to H₂O₂ and Sb³⁺ revealed higher IC₅₀ values in the <em>Lbnmnat</em>-edited parasites. These findings denote a correlation between the upregulated biosynthesis of NAD in <em>L. braziliensis</em> and its enhanced resistance to oxidative stress, indicating that the <em>Lbnmnat</em> gene may play a significant role in the survival and resistance mechanisms of the parasite against antimony compounds.</div></div>","PeriodicalId":12117,"journal":{"name":"Experimental parasitology","volume":"275 ","pages":"Article 108979"},"PeriodicalIF":1.4,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144474385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}