Acta tropica最新文献

{"title":"Characterization of hemotropic Mycoplasma (hemoplasma) isolates from Thai domestic pigs using the 23S ribosomal RNA gene","authors":"Kritsada Thongmeesee ,&nbsp;Duriyang Narapakdeesakul ,&nbsp;Morakot Kaewthamasorn ,&nbsp;Suphot Wattanaphansak ,&nbsp;Sonthaya Tiawsirisup","doi":"10.1016/j.actatropica.2025.107698","DOIUrl":"10.1016/j.actatropica.2025.107698","url":null,"abstract":"<div><div>Hemotropic <em>Mycoplasma</em>, also known as hemoplasma, is a group of bacteria belonging to the Mollicutes, responsible for causing infectious anemia in various mammalian hosts, including pigs. Based on 16S rRNA gene characterization at the species level, porcine hemoplasmas have previously been classified as <em>Mycoplasma (M.) suis</em>, M<em>. parvum</em>, ‘<em>Candidatus (Ca.)</em> M. haemosuis’, and a potentially novel species. However, due to the high sequence similarity across hemoplasmas, the 16S rRNA gene cannot differentiate at the species level. Consequently, another genetic marker, the 23S rRNA gene, has been proposed for this purpose. In our study, we employed the 23S rRNA gene to characterize porcine hemoplasma isolates (n = 49) in our laboratory, using blast analysis, phylogenetic analysis and genetic network analysis. Through the approach using the 23S rRNA gene, we could identify at least six clusters or hemoplasma species from five groups of 16S rRNA sequences found in Thai pigs. Additionally, we could elucidate one ambiguous group from a previous study as <em>M. parvum</em>. This one ambiguous group potentially represented either <em>M. suis</em> or <em>M. parvum</em> group (ntST#4) from the 16S rRNA gene alone. Notably, two of the six clusters may represent putative novel species. These findings underscore the utility of the 23S rRNA gene in characterizing and surveying of hemoplasma infection in domestic pigs globally.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"268 ","pages":"Article 107698"},"PeriodicalIF":2.1,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intense rainfalls and floods reshape malaria transmission in Niger","authors":"Médard Djedanem ,&nbsp;Noura Mamane Sale ,&nbsp;Elhadji Yacoudima Y.M. Aminou ,&nbsp;Luc Descroix ,&nbsp;Jean Testa ,&nbsp;Ronan Jambou","doi":"10.1016/j.actatropica.2025.107699","DOIUrl":"10.1016/j.actatropica.2025.107699","url":null,"abstract":"<div><h3>Problem considered</h3><div>The Sahel covers a vast semi-arid area characterized by a long dry season of about 8–9 months and a short rainy season of 3–4 months. Although arid, the Sahel is highly susceptible to vector-borne diseases, and a malaria endemic zone. After decades of drought, rainfall is increasing again, leading to a sustained increase in malaria transmission in the region. Changes in land use and urbanization are also modulating human-vector contacts and thus the incidence of malaria. Malaria control programs need to adapt to this situation. The aim of this study is to discuss the factors influencing malaria occurrence in this region, which are modulated by climate and land use.</div></div><div><h3>Methods</h3><div>For this study, both original epidemiological data and recent literature are analyzed to support the discussion on adaptation of control strategies.</div></div><div><h3>Results</h3><div>Overall, the perennial presence of water resulting from rainfall and/or human activities are key factors in stabilizing malaria transmission in the Sahel. Indeed, recent studies show that in Niger, transmission is increasing, but also spreading during the dry season, especially in areas closed to wild water and flooding. In the same vein, malaria morbidity is no longer largely confined to children under five.</div></div><div><h3>Conclusions</h3><div>Preventive measures, including chemoprevention of seasonal malaria and indoor residual spraying, which are currently used only during the rainy season, need to be redesigned as part of a rethink of current prevention strategies. Policy-makers and national programs should adapt their strategies to better fit the future climatic context of the Sahel.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"268 ","pages":"Article 107699"},"PeriodicalIF":2.1,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coxiella burnetii detected in Rhipicephalus sanguineus ticks collected in Portuguese autochthonous livestock","authors":"Sara Gomes-Gonçalves ,&nbsp;João R. Mesquita ,&nbsp;Zita Martins Ruano ,&nbsp;Patrícia F. Barradas","doi":"10.1016/j.actatropica.2025.107697","DOIUrl":"10.1016/j.actatropica.2025.107697","url":null,"abstract":"<div><div><em>Coxiella burnetii</em> is a bacterium that causes coxiellosis in animals and Q fever in humans. While ruminants are the main reservoirs, the role of ticks in their transmission is still uncertain. This study looked for <em>C. burnetii</em> in ticks collected from two autochthonous breeds in Portugal: Churra Galega Mirandesa sheep and Garrano horses. A total of 555 ticks were tested, including 100 <em>Rhipicephalus sanguineus</em> sensu (s.) stricto (s.) from sheep and 455 <em>Rhipicephalus bursa</em> from horses. <em>Coxiella burnetii</em> was found in 7 % of <em>R. sanguineus</em> s.s., but not in <em>R. bursa</em>. Phylogenetic analysis confirmed the strains. These findings suggest that <em>R. sanguineus</em> s.s. may play a role in the bacterium's presence in livestock. Further research is needed to clarify the role of ticks in <em>C. burnetii</em> transmission in Portugal.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"268 ","pages":"Article 107697"},"PeriodicalIF":2.1,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the prevalence of oral trichomonads in patients with periodontitis at a tertiary teaching hospital","authors":"Nurin Jazlina Nor Azmi ,&nbsp;Haslina Taib ,&nbsp;Zeehaida Mohamed ,&nbsp;Nik Zairi Zakaria ,&nbsp;Nik Zuraina Nik Mohd Noor ,&nbsp;Suharni Mohamad","doi":"10.1016/j.actatropica.2025.107696","DOIUrl":"10.1016/j.actatropica.2025.107696","url":null,"abstract":"<div><div><em>Trichomonas tenax</em> is an oral protozoan associated with periodontitis, a chronic inflammatory disease affecting the periodontal tissues. Although globally recognized, its role in oral health remains unclear, and no data exist on its prevalence in Malaysia. This study aimed to determine the incidence of <em>T. tenax</em> in a Malaysian population and assess its association with periodontitis. A total of 30 subjects (15 patients with periodontitis, 15 controls) were recruited at Hospital Universiti Sains Malaysia. Saliva and subgingival dental plaque samples were collected and analyzed using direct microscopy, selective culture, and polymerase chain reaction (PCR) targeting the 18S rRNA gene, with sequencing for confirmation. <em>T. tenax</em> was detected exclusively in the periodontitis group (13.3 %, 2/15). PCR yielded a 776 base-pair amplicon and demonstrated the highest sensitivity, identifying <em>T. tenax</em> in 6.7 % (2/30) of subgingival dental plaque samples and 3.3 % (1/30) of saliva sample. Microscopy and culture showed limited effectiveness, with no positive results from microscopy and only one positive culture from saliva. These findings represent the first confirmed detection of <em>T. tenax</em> in Malaysia and underscores its association with periodontitis. PCR is recommended as the preferred detection method. Further studies are warranted to clarify the pathogenic role of <em>T. tenax</em> and its broader epidemiological significance.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"268 ","pages":"Article 107696"},"PeriodicalIF":2.1,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144300949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global prevalence of Human Demodex Mite: A systematic review and meta-analysis","authors":"Bahman Maleki ,&nbsp;Nahid Haghshenas ,&nbsp;Mostafa Rezaei-Tavirani ,&nbsp;Alireza Ahmadzadeh ,&nbsp;Ahmad Abolghazi ,&nbsp;Reza M Robati","doi":"10.1016/j.actatropica.2025.107693","DOIUrl":"10.1016/j.actatropica.2025.107693","url":null,"abstract":"<div><div><em>Demodex</em> mites are common ectoparasites in humans that typically reside as commensals in sebaceous glands, but under certain host conditions, they may become opportunistic pathogens. Despite numerous localized studies on the prevalence of human <em>Demodex</em> mites, the global prevalence and associated risk factors remain unclear. This study aims to systematically assess the global prevalence of human <em>Demodex</em> mites and the effects of age, gender, facial sampling region, humidity, World Health Organization (WHO) regions and countries, and population factors on this prevalence. A systematic literature search, following PRISMA guidelines, was conducted in multiple databases from January 2000 to January 2025. Meta-analysis using a random-effects model estimated the global prevalence of <em>Demodex</em> mites and examined associations with demographic, geographic, and climatic factors. Meta-regression, sensitivity analysis, and Egger’s test were conducted to assess publication bias and the robustness of the findings. The global pooled prevalence of human <em>Demodex</em> mites was approximately 35 % (based on available studies), with the highest prevalence observed in the South-East Asia Region (SEARO) at 44 %. The highest prevalence among age groups was found in older adults (&gt;60 years), reaching 59 %, while the highest facial region-specific prevalence was observed in the eyelashes at 33 %. Among different population groups, ophthalmology patients showed the highest prevalence (57 %). Additionally, the prevalence was slightly higher in females compared to males. The analysis revealed significant heterogeneity and publication bias. The sensitivity analysis confirmed the stability of the prevalence estimate. Meta-regression identified significant differences in sample size but no associations with humidity or publication year. This meta-analysis highlights a global prevalence of human <em>Demodex</em> mites, especially among older adults and ophthalmology patients, emphasizing the need for clinical awareness and further studies.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"268 ","pages":"Article 107693"},"PeriodicalIF":2.1,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144293149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity and population structure of Prosimulium rachiliense Djafarov (Diptera: Simuliidae) inTürkiye","authors":"Davut Ümit Şirin,&nbsp;Büşra Aslan Kocatürk","doi":"10.1016/j.actatropica.2025.107694","DOIUrl":"10.1016/j.actatropica.2025.107694","url":null,"abstract":"<div><div>The family Simuliidae contains many cryptic species within multiple species groups. <em>Prosimulium rachiliense</em> Djafarov, a member of the <em>P. hirtipes</em> species group, is widespread throughout Anatolia. Previous chromosomal research revealed that populations of <em>P. rachiliense</em> in western Anatolia differ cytogenetically from populations in Armenia. We used mitochondrial COI and nuclear ITSI-II sequences to perform phylogenetic analysis and species delimitation tests to reveal the genetic diversity of <em>P. rachiliense</em> in Anatolia and to test the possibility of cryptic lineages. Our results indicated two distinct lineages, one in eastern and one in western Türkiye, with significant genetic diversity in both lineages. Although species delimitation tests with COI dataset suggested multiple candidate species, those with ITS I-II and phylogenetic analyses indicated that <em>P. rachliense</em> is a single species with great genetic diversity. Phylogenetic analysis with COI confirmed that <em>P. rachiliense</em> is a nominal species within the <em>hirtipes</em> species group. Further analyses are needed using genome-wide SNP data with comprehensive sampling to understand deep population structure of <em>P. rachiliense</em> in Türkiye.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"268 ","pages":"Article 107694"},"PeriodicalIF":2.1,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144279945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzymatic mechanisms of insecticide resistance in Anopheles sp mosquitoes: Implications for malaria vector control in Indonesia","authors":"Rizal Subahar ,&nbsp;Lisawati Susanto ,&nbsp;Surya Dwira ,&nbsp;Hendri Astuty ,&nbsp;Nurhadi Eko Firmansyah ,&nbsp;Gulshan Fahmi El Bayani ,&nbsp;Tilahun Adugna ,&nbsp;Syarifah Dewi ,&nbsp;Fadillah","doi":"10.1016/j.actatropica.2025.107691","DOIUrl":"10.1016/j.actatropica.2025.107691","url":null,"abstract":"<div><div>Malaria remains a major public health concern worldwide, with Anopheles mosquitoes serving as its primary vectors. The widespread use of synthetic insecticides in malaria control programs has resulted in the development of insecticide resistance in these mosquitoes, endangering control efforts. This study investigates metabolic resistance mechanisms in wild-caught Anopheles spp. from three regencies in Indonesia (Pesawaran, Pangandaran, and Purworejo), with an emphasis on enzymatic activity and ace-1 gene mutations. Anopheles mosquitoes were collected using human landing capture (HLC) and cow-baited collection (CLC). Biochemical assays were performed to evaluate the activity of acetylcholinesterase (AChE), glutathione S-transferase (GST), and oxidase. Additionally, ace-1 gene mutations were analyzed using PCR-RFLP. Seven Anopheles species were identified. Statistical analysis revealed significant differences in mosquito distribution across the regencies based on HLC (<em>P</em> &lt; 0.05). All Anopheles populations exhibited significantly elevated AChE and GST activity (<em>P</em> &lt; 0.05), suggesting strong metabolic resistance. Anopheles barbirostris from Pesawaran regency exhibited heterozygous ace-1 gene mutations (194, 120, and 74 bp bands), classifying it within AChE resistance group A. The findings confirm widespread metabolic resistance in Anopheles mosquitoes across Indonesia, which is most likely caused by chronic insecticide exposure. Continuous monitoring of insecticide resistance and its underlying mechanisms is critical to sustain malaria control and eradication efforts in Indonesia.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"268 ","pages":"Article 107691"},"PeriodicalIF":2.1,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144273935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bug as a drug: Unveiling anti-cancer properties of Toxoplasma gondii and its therapeutic prospects in cancer immunotherapy","authors":"Yie Wei Chua,&nbsp;Sek Chuen Chow","doi":"10.1016/j.actatropica.2025.107684","DOIUrl":"10.1016/j.actatropica.2025.107684","url":null,"abstract":"<div><div>In light of the growing global cancer burden, the development of novel therapeutic strategies is urgently needed. Recently, pathogens have been examined for their potential in immunotherapy, with <em>Toxoplasma gondii</em> (<em>T. gondii</em>) emerging as an unexpected yet promising candidate. Given the widespread prevalence of <em>T. gondii</em>, particularly in tropical regions where climatic conditions favor the oocyst transmission, understanding its therapeutic potential may have far-reaching implications for global health. This review explores the potential of <em>T. gondii</em> as a cancer immunotherapy by examining various <em>T. gondii</em> variants characterized in current studies. It highlights the multifaceted mechanisms behind <em>T. gondii</em>'s anti-cancer properties, including the induction of Th1 immune responses, immunostimulation of the tumor microenvironment, inhibition of angiogenesis, invasion and metastasis, as well as the induction of cancer cell apoptosis. However, several challenges hinder the application of <em>T. gondii</em> in immunotherapy, such as safety concerns related to viable <em>T. gondii</em>, its limited efficacy against non-solid tumors, and the need for further validation of non-viable <em>T. gondii</em> components. Additionally, the role of humoral immunity and potential synergies with conventional therapies require further investigation. Addressing these challenges could significantly enhance the efficacy and safety of <em>T. gondii</em>-based immunotherapy, offering a novel approach to cancer treatment and potentially improving patient outcomes.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107684"},"PeriodicalIF":2.1,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144242665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation, purification, structure elucidation, and antibody recognition of two phospholipases A2 and Crotoxin variation in the venom of the Tamaulipan rattlesnake Crotalus morulus","authors":"Miguel Angel Mejía-Sánchez ,&nbsp;Samuel Cardoso-Arenas ,&nbsp;Ricardo Miranda-Blancas ,&nbsp;Adrián Marcelo Franco-Vásquez ,&nbsp;Alejandro Carbajal-Saucedo ,&nbsp;Timoteo Olamendi-Portugal ,&nbsp;Fernando Zamudio ,&nbsp;Roberto Arreguín-Espinosa ,&nbsp;Gerardo Corzo","doi":"10.1016/j.actatropica.2025.107690","DOIUrl":"10.1016/j.actatropica.2025.107690","url":null,"abstract":"<div><div>The venom of six individuals of <em>Crotalus morulus</em>, an unstudied endemic species of Mexico, was analyzed by anti-crotoxin antibodies (anti-rCrotxB and anti-rCrotxAB) obtained from recombinant expression of crotoxin B and of a tandem protein containing both crotoxin A and B, to discern which individuals from the species <em>C. morulus</em> contain crotoxin. As a result, two new phospholipases were identified from only one of the six individuals named <em>C. morulus</em> 1032, which had the most toxic venom with a low median lethal dose (LD₅₀ &lt; 40 μg/20 g mouse). RP-HPLC fractionation and a combination of Edman degradation and endoproteolytic cleavages elucidated the primary structure of such phospholipases. The assigned names were Cm-PLA₂–1 and Cm-PLA₂–2, respectively. Cm-PLA₂–1 is a phospholipase type A₂ that showed neurotoxic activity towards mice with an LD₅₀ value of 16.6 μg/20 g mouse. Cm-PLA₂–1 is 92 % identical to crotoxin B from the venom of <em>Crotalus durissus terrificus.</em> The second phospholipase type A₂, Cm-PLA₂–2, did not cause lethality or any apparent signs of toxicity in mice when injected by the intravenous route up to a dose of 30 μg/20 g mouse. Two commercial antivenoms and anti-crotoxin B could not inhibit the enzymatic activity of Cm-PLA₂–1; however, they neutralize the venom of <em>C. morulus</em> 1032 with an ED₅₀ of &lt; 40 mg antibody/mg venom. Identification of <em>crotoxin-like</em> toxins in rattlesnake species is essential to understanding the mechanisms of envenomation of these crotalids, since some individuals have more toxic venom than others. Therefore, concerning crotalid antivenoms, attention must be paid to selecting species with crotoxin to be used as immunogens. This work provides information for future research on their crotalid toxicity and effects on humans.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"267 ","pages":"Article 107690"},"PeriodicalIF":2.1,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144261632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FERAI, a novel brominated chalcone, induces ultrastructural alterations and apoptosis like-death in Leishmania braziliensis","authors":"Francisnaira da Silva Santos ,&nbsp;Gleice Rayanne Silva ,&nbsp;Laísia Alonso Uzêda ,&nbsp;Catarina Araújo Menezes Campos ,&nbsp;Fernando Leite Ferreira ,&nbsp;Felipe Sarmento Guerra ,&nbsp;Luís Cesar Rodrigues ,&nbsp;Hemerson Iury Ferreira Magalhães ,&nbsp;Francisco Jaime Bezerra Mendonça Junior ,&nbsp;Milena Botelho Pereira Soares ,&nbsp;Elisalva Teixeira Guimarães","doi":"10.1016/j.actatropica.2025.107689","DOIUrl":"10.1016/j.actatropica.2025.107689","url":null,"abstract":"<div><div>Chalcones hold significant potential as bioactive agents due to their simple chemical structure and the possibility of generating more potent derivatives through strategic structural modifications. In a previous study, our research group evaluated the in vitro antileishmanial activity of (E)-1-(benzo[d][1,3]dioxol-5-yl)-3-(3‑bromo-4-ethoxy-5-methoxyphenyl)prop‑2-en-1-one (FERAI) against <em>Leishmania braziliensis</em> promastigotes and amastigotes. The present study aimed to investigate the mechanisms of action of this compound in L. <em>braziliensis</em> parasites. Ultrastructural changes were examined using scanning and transmission electron microscopy. Cell death patterns and mitochondrial membrane potential were assessed by flow cytometry. Scanning electron microscopy revealed morphological alterations in promastigotes, including cell body retraction and plasma membrane disruption. Transmission electron microscopy showed the presence of lipid inclusions, mitochondrial alterations, nuclear swelling, and flagellar loss. In addition, FERAI induced mitochondrial membrane depolarization and triggered apoptotic cell death in L. <em>braziliensis</em> promastigotes. Collectively, these findings suggest that mitochondrial depolarization and direct morphological damage to the parasite, followed by programmed cell death, are central mechanisms of FERAI action against L. <em>braziliensis</em> promastigotes. The elucidation of FERAI's mechanisms of action highlights its potential as a promising candidate for the development of new drugs against leishmaniasis.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"268 ","pages":"Article 107689"},"PeriodicalIF":2.1,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144265043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}