International Journal for Parasitology: Drugs and Drug Resistance最新文献_第5页

Three Asparagine insertions in the K13-propeller led to Plasmodium falciparum becoming resistant to multiple antimalarial drugs 在k13推进器中插入三个天冬酰胺导致恶性疟原虫对多种抗疟疾药物产生耐药性

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-04-25 DOI: 10.1016/j.ijpddr.2025.100590

Zheng Xiang , Mengxi Duan , Siqi Wang , Hui Zhao , Wei Zhao , Xiaosong Li , Xinxin Li , Weilin Zeng , Yanrui Wu , Fuxue Yang , Xinyu Liu , Cong Tang , Liwang Cui , Zhaoqing Yang

Drug resistance in Plasmodium falciparum represents a significant challenge in malaria treatment. Identifying the molecular markers associated with P. falciparum resistance will effectively detect resistance and enhance treatment efficiency. In this study, we utilized the advanced CRISPR/Cas9 technology to precisely insert one, two, or three asparagine residues into the Kelch 13(K13) gene of the 3D7 strain, positioned after the 142nd amino acid residue, resulting in 1N-3D7, 2N-3D7, and 3N-3D7. Using ring-stage survival assays (RSA), drug sensitivity evaluations, and in vitro developmental assessments, our findings revealed a trend: 1) the insertion of asparagine residues into the parasite genome increased RSA, with more asparagine insertions leading to higher RSA. 2) According to the IC50 values, 1N-3D7 and 2N-3D7 exhibited similar sensitivity profiles across all ten tested drugs, with both demonstrating resistance to Naphthoquine, indicating that the insertions of one or two asparagines played an equivalent role in conferring resistance. However, the insertion of three asparagine residues resulted in significantly higher IC50 values compared to the first two forms when tested with Artesunate, Artemether, Dihydroartemisinin, Pyronaridine Phosphate, and Naphthoquine, showing resistance to all five drugs. Furthermore, 3N-3D7 exhibited a prolonged ring phase and a shortened trophozoite phase within red blood cells; the schizont phase appeared synchronous with the others, yet its mature schizonts contained fewer merozoites. Additionally, 3N-3D7 exhibited a fitness defect, with the proportion decreasing gradually during co-culture with 3D7, its fitness cost calculated as 14.88 ± 2.87. All these results support the opinion that the insertion of three asparagines was a molecular marker of resistance to artemisinin derivatives, Pyronaridine Phosphate, and Naphthoquine in P. falciparum.

恶性疟原虫的耐药性是疟疾治疗的一个重大挑战。鉴定恶性疟原虫耐药相关分子标记，将有效发现耐药性，提高治疗效率。在本研究中，我们利用先进的CRISPR/Cas9技术，在3D7菌株的Kelch 13（K13）基因中精确插入1、2或3个天冬酰胺残基，定位在第142个氨基酸残基之后，得到1N-3D7、2N-3D7和3N-3D7。通过环期生存试验（RSA）、药物敏感性评估和体外发育评估，我们的研究结果揭示了一个趋势：1)天冬酰胺残基插入寄生虫基因组增加了RSA，天冬酰胺插入越多，RSA越高。2)根据IC50值，1N-3D7和2N-3D7对10种被试药物的敏感性相似，均对萘醌产生耐药性，表明一种或两种天冬酰胺的插入对萘醌产生耐药性的作用相同。然而，当与青蒿琥酯、蒿甲醚、双氢青蒿素、磷酸吡啶和萘喹进行测试时，插入三种天冬酰胺残留物的IC50值明显高于前两种形式，显示出对所有五种药物的耐药性。3N-3D7红细胞内环期延长，滋养体期缩短；分裂体阶段与其他阶段同步，但其成熟分裂体含有较少的分裂子。3N-3D7存在适合度缺陷，在与3D7共培养过程中比例逐渐降低，其适合度成本计算为14.88±2.87。这些结果支持了3个天冬酰胺的插入是恶性疟原虫对青蒿素衍生物、磷酸吡啶和萘喹耐药的分子标记。

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引用次数: 0

Metabolomics study of 3-O-p-(Z/E)-coumaroyltormentic acid-treated Trypanosoma brucei brucei 3-O-p-(Z/E)-香豆醇折磨酸处理的布鲁氏锥虫代谢组学研究

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-04-16 DOI: 10.1016/j.ijpddr.2025.100595

Lúcia Mamede , Fanta Fall , Madeline Vast , Kristelle Hughes , Giorgia Martelli , Francesco Caligiore , Bernadette Govaerts , Paul A.M. Michels , Michel Frédérich , Joëlle Quetin-Leclercq

Trypanosomiasis is a parasitic disease for which new treatments are needed due to the frequent occurrence of adverse side effects of current available drugs. Natural compounds found in traditionally used plants offer opportunities to discover innovative compounds that could prove pivotal to antitrypanosomal drug development. 3-O-p-(Z/E)-coumaroyltormentic acids (CTA) were isolated first from the West Africa-native tree Vitellaria paradoxa and have demonstrated quite selective in vitro and in vivo antitrypanosomal activity, despite the unknown mode of action. In this study, a metabolomics analysis using the data from both LC-HR-MS and ¹H-NMR described CTA's effects on Trypanosoma brucei after 3 h exposure under 5 or 10 x EC₅₀. Our study shows CTA's activity impacted tryptophan metabolism and reveals potential targets in different branches of this metabolism. Our results demonstrate a likely presence of enzymes dedicated to tryptophan, like a tryptophan aminotransferase, tryptophan 2,3-dioxygenase and/or indoleamine 2,3-dioxygenase, and other enzymes of the kynurenine pathway, despite the absence of their description thus far in this species. These data further implicate that CTA's toxic effect on the tryptophan metabolism may be attributed to the decrease of the intracellular level of essential aspartate, resulting from inhibition of its aminotransferase. In resume, our study shines light on the likelihood of the tryptophan metabolism pathway presenting innovative targets toward the development of antitrypanosomal drugs. These require confirmation through functional and enzymatic studies.

锥虫病是一种寄生虫病，由于现有药物经常发生不良副作用，需要新的治疗方法。在传统使用的植物中发现的天然化合物为发现可能被证明对抗锥虫药物开发至关重要的创新化合物提供了机会。3-O-p-(Z/E)-香豆醇折磨酸（CTA）首先从西非原生树Vitellaria paradoxa中分离出来，尽管作用方式未知，但在体外和体内均表现出相当选择性的抗锥虫活性。在这项研究中，利用LC-HR-MS和1H-NMR的数据进行代谢组学分析，描述了CTA在5或10倍EC50下暴露3小时后对布鲁氏锥虫的影响。我们的研究表明，CTA的活性影响色氨酸代谢，并揭示了这种代谢的不同分支的潜在靶点。我们的研究结果表明可能存在专门用于色氨酸的酶，如色氨酸转氨酶，色氨酸2,3-双加氧酶和/或吲哚胺2,3-双加氧酶，以及犬尿氨酸途径的其他酶，尽管迄今为止在该物种中缺乏描述。这些数据进一步表明，CTA对色氨酸代谢的毒性作用可能是由于其转氨酶的抑制导致细胞内必需天冬氨酸水平的降低。总之，我们的研究揭示了色氨酸代谢途径为抗锥虫药物的开发提供创新靶点的可能性。这些需要通过功能和酶的研究来证实。

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引用次数: 0

Effect of urea and squaramide IMPDH inhibitors on C. parvum: in vitro trial design impacts the assessment of drug efficacy 尿素和方酰胺IMPDH抑制剂对细小弧菌的影响：体外试验设计影响药效评估

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-04-15 DOI: 10.1016/j.ijpddr.2025.100592

Anne-Charlotte Lenière , Amit Upadhyay , Jérôme Follet , Timothy P. O'Sullivan

The protozoan parasite Cryptosporidium is the etiological agent of cryptosporidiosis, a ubiquitous diarrheic disease affecting humans and animals. Treatment options are limited, highlighting an urgent need for novel therapeutics. Despite decades of research and a wide diversity of strategies to tackle parasite metabolic pathways, no completely effective drug has been identified to date. Within targeted parasite enzymatic and metabolic pathways, the synthesis of nucleotide mediated by the inosine 5′-monophosphate dehydrogenase (IMPDH) enzyme is the focus of significant research efforts. Based on our prior studies of bacterial IMPDH inhibitors, we report herein the development and characterisation of novel inhibitors targeting Cryptosporidium parvum IMPDH (CpIMPDH). Specifically, we synthesised heteroaryl-containing urea and squaramide analogues to evaluate their potential in vitro anti-Cryptosporidium activity. Initial screening identified nine active compounds with the most potent candidates achieving IC₅₀ values as low as 2.2 μM. Subsequent time-course experiments revealed that the molecules effectively inhibit parasite invasion and early intracellular development but failed to tackle C. parvum growth when introduced at 30 h post infection. The present work introduces a new family of squaramide-derived IMPDH inhibitors and also interrogates the need to standardise commonly accepted protocols used for assessing anti-cryptosporidial drug activity.

隐孢子虫病是一种影响人类和动物的普遍腹泻疾病，隐孢子虫原虫是隐孢子虫病的病原。治疗选择有限，迫切需要新的治疗方法。尽管经过数十年的研究和各种各样的策略来解决寄生虫的代谢途径，但迄今为止还没有发现完全有效的药物。在针对寄生虫的酶和代谢途径中，肌苷5 ' -单磷酸脱氢酶（IMPDH）酶介导的核苷酸合成是重要的研究重点。基于我们之前对细菌IMPDH抑制剂的研究，我们在此报告了针对小隐孢子虫IMPDH （CpIMPDH）的新型抑制剂的开发和表征。具体而言，我们合成了含异芳基脲和方酰胺类似物，以评估其体外抗隐孢子虫活性的潜力。初步筛选鉴定出9种活性化合物，其中最有效的候选化合物IC50值低至2.2 μM。随后的时间过程实验表明，这些分子可以有效抑制寄生虫的入侵和早期细胞内发育，但在感染后30小时引入时，无法抑制小孢子虫的生长。本研究介绍了一种新的由角鲨酰胺衍生的IMPDH抑制剂家族，并探讨了对用于评估抗隐孢子虫药物活性的普遍接受的方案进行标准化的必要性。

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引用次数: 0

Ursolic acid induces apoptosis and disrupts host-parasite interactions in Theileria annulata-infected cells 熊果酸诱导环孢杆菌感染细胞凋亡并破坏宿主-寄生虫相互作用

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-04-14 DOI: 10.1016/j.ijpddr.2025.100593

Sakshi Singh , Madhusmita Subudhi , Vengatachala Moorthy A , Akash Suresh , Paresh Sharma

This study explores the anti-proliferative and anti-parasitic properties of ursolic acid (UA) in Theileria annulata-infected bovine (TA) cells. Dose-response analyses determined an IC₅₀ value of approximately 5 μg/mL for UA, demonstrating selective cytotoxicity toward infected cells with minimal impact on healthy cells. UA treatment induced pronounced morphological alterations and apoptosis in TA cells, as evidenced by light microscopy and a time-dependent increase in cell mortality. Notably, UA exhibited consistent efficacy against both buparvaquone (BPQ)-sensitive and BPQ-resistant TA cell lines, highlighting its broad-spectrum anti-parasitic potential. Mechanistic investigations revealed that UA triggers DNA damage, elevates reactive oxygen species (ROS) levels, disrupts mitochondrial function, and induces sub-G1 phase arrest, culminating in apoptosis primarily via the intrinsic pathway. Mass spectrometry-based proteomic profiling identified significant perturbations in host cell pathways, including DNA repair mechanisms, cell cycle regulation, and signaling networks, alongside direct interference with parasite metabolic processes. Western blot analysis further confirmed UA-mediated modulation of host cell signaling pathways and chromatin organization. Given the rising incidence of drug-resistant T. annulata strains, the development of novel therapeutic strategies is imperative. These findings highlight UA's multifaceted mechanism of action, targeting both parasitic and host cellular processes, and position it as a promising candidate for the treatment of bovine theileriosis.

本研究探讨熊果酸（UA）在环孢杆菌感染牛（TA）细胞中的抗增殖和抗寄生特性。剂量-反应分析确定UA的IC50值约为5 μg/mL，表明对感染细胞具有选择性细胞毒性，对健康细胞的影响最小。光镜和时间依赖性细胞死亡率的增加证实了UA处理诱导TA细胞明显的形态学改变和凋亡。值得注意的是，UA对布帕伐酮（BPQ）敏感和抗BPQ的TA细胞系均表现出一致的功效，突出了其广谱抗寄生虫潜力。机制研究表明，UA触发DNA损伤，提高活性氧（ROS）水平，破坏线粒体功能，诱导亚g1期阻滞，主要通过内在途径最终导致细胞凋亡。基于质谱的蛋白质组学分析鉴定了宿主细胞通路的显著扰动，包括DNA修复机制、细胞周期调节和信号网络，以及对寄生虫代谢过程的直接干扰。Western blot分析进一步证实了ua介导的宿主细胞信号通路和染色质组织的调节。鉴于耐药环状单胞菌株的发病率不断上升，开发新的治疗策略势在必行。这些发现突出了UA的多方面作用机制，针对寄生和宿主细胞过程，并将其定位为治疗牛肠道菌病的有希望的候选药物。

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引用次数: 0

High frequency of benzimidazole resistance polymorphisms and age-class differences in trichostrongyle nematodes of ranched bison from the south-central United States 美国中南部放牧野牛毛线虫苯并咪唑抗性多态性的高频率及年龄级差异

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-04-14 DOI: 10.1016/j.ijpddr.2025.100594

Kaylee R. Kipp , Elizabeth M. Redman , Joe L. Luksovsky , Dani Claussen , John S. Gilleard , Guilherme G. Verocai

Bison production is a growing sector of the United States agriculture, with more consumers choosing bison products. Commercial bison are kept on smaller pastures and treated with anthelmintics for gastrointestinal nematodes (GIN) to maintain production. However, there is a lack of information regarding the GIN parasite communities in ranched bison or the extent of their resistance to anthelmintics. Our objectives were: i) to determine the GIN species present and the extent of resistance to the benzimidazole drug class in commercial bison herds in the southern US and ii) to assess age class differences in GIN species composition and BZ resistance. Composite coprocultures from bison in Texas (n = 14) and Oklahoma (n = 2), and individual bison of different age classes from a single ranch in central Texas (n = 43) were analyzed using ITS2 rDNA nemabiome metabarcoding to determine the trichostrongylid species composition. For both the composite and individual samples, the most common trichostrongylid species found were Haemonchus contortus, Haemonchus placei, and Ostertagia ostertagi. Among the known canonical isotype-1 β-tubulin BZ resistance polymorphisms (at codons 200, 198, 167), the 200Y (TTC > TAC) substitution was the most widespread across the two southern states, with a prevalence of 81.3 %. Other polymorphisms, such as 167Y (TTC > TAC) and 198L (GAA > TTA), were also detected, and both had prevalences of 62.5 %. Ostertagia ostertagi was found to have very high frequencies (overall mean frequency = 62.6 %; range = 28.3–100 %) of the 200Y (TTC > TAC) polymorphism in all age classes sampled. Overall, benzimidazole resistance polymorphisms were found at moderate to high frequency in the three major economically important GIN species in ranched bison in Texas and Oklahoma, suggesting a potential widespread distribution of benzimidazole resistance polymorphisms in the southern United States. This work has important implications for all other grazing livestock and illustrates the importance of early detection of anthelmintic resistance and the need for mitigation strategies.

随着越来越多的消费者选择野牛产品，野牛生产是美国农业中一个不断增长的部门。商业野牛被饲养在较小的牧场上，并使用胃肠线虫（GIN）驱虫剂来维持生产。然而，关于野生野牛体内的GIN寄生虫群落或它们对驱虫药的抗性程度的信息缺乏。我们的目标是：i)确定美国南部商业野牛群中存在的GIN物种和对苯并咪唑类药物的耐药程度；ii)评估GIN物种组成和BZ耐药性的年龄差异。采用ITS2 rDNA基因组元条形码技术，分析了来自德克萨斯州（n = 14）和俄克拉荷马州（n = 2）的复合共培养物，以及来自德克萨斯州中部单一牧场（n = 43）的不同年龄等级的野牛个体，以确定毛线虫的物种组成。在复合样本和单个样本中，最常见的毛线虫种类是扭曲血蜱、地方血蜱和Ostertagia ostertagi。在已知的典型同型-1 β-微管蛋白BZ抗性多态性（密码子200,198,167）中，200Y (TTC >；TAC)替代在南部两个州最为普遍，患病率为81.3%。其他多态性，如167Y (TTC >；TAC)和198L (GAA >；TTA)，两者的患病率均为62.5%。Ostertagia ostertagi被发现有非常高的频率(总体平均频率= 62.6%；范围= 28.3 - 100%)(TTC >；TAC)多态性在所有年龄组的抽样。总体而言，在德克萨斯州和俄克拉何马州的牧场野牛中，三种主要的具有重要经济意义的GIN物种中苯并咪唑抗性多态性呈中高频分布，表明苯并咪唑抗性多态性可能在美国南部广泛分布。这项工作对所有其他放牧牲畜具有重要意义，并说明了早期发现抗虫性的重要性和制定缓解策略的必要性。

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引用次数: 0

Tartrolon E rapidly blocks Toxoplasma gondii capacity to invade host cells Tartrolon E迅速阻断弓形虫入侵宿主细胞的能力

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-04-14 DOI: 10.1016/j.ijpddr.2025.100591

Fernanda G. Fumuso , Jason A. Clement , Matthew J. Todd , Roberta M. O'Connor

Toxoplasmosis is a worldwide parasitic disease caused by the apicomplexan Toxoplasma gondii. Severe neurological illness occurs in immunosuppressed patients, and congenital disorders can follow transplacental primo infection during pregnancy. New effective antiparasitic drugs are needed since chronic cystic stages are resistant to current available treatments, and some of the congenital infections are unresponsive to available therapeutics. Tartrolon E (trtE) is a marine secondary metabolite that has high selectivity against human and animal apicomplexan parasites including T. gondii, Cryptosporidium parvum and Plasmodium falciparum. We evaluated the effect of the compound on extracellular tachyzoite viability, morphology, membrane permeability and its ability to block host cell attachment and/or invasion. While 80 % of T. gondii infective capacity is blocked after only 30 min of compound treatment, parasite viability, morphology, membrane integrity and host cell attachment were unaffected until after 4 h of treatment. These effects were irreversible when parasites were allowed to infect host cells after trtE treatment. Drug exposure for more than 4 h significantly affected tachyzoite survival and altered parasite morphology. The mechanism of action of trtE is still unknown but includes blocking parasite invasion processes. Further research is needed to determine the molecular target of trtE to further progress the compound as an antiparasitic candidate.

弓形虫病是由弓形虫顶复体引起的一种世界性寄生虫病。严重的神经系统疾病发生在免疫抑制的患者中，先天性疾病可在怀孕期间发生经胎盘原发性感染。需要新的有效的抗寄生虫药物，因为慢性囊性病变对现有的治疗方法有抗药性，而且一些先天性感染对现有的治疗方法没有反应。Tartrolon E （trtE）是一种海洋次生代谢物，对人类和动物的顶复体寄生虫，包括弓形虫、小隐孢子虫和恶性疟原虫有很高的选择性。我们评估了该化合物对细胞外速殖子活力、形态、膜通透性及其阻止宿主细胞附着和/或入侵的能力的影响。虽然80%的弓形虫感染能力在复合处理30分钟后被阻断，但寄生虫的活力、形态、膜完整性和宿主细胞附着直到处理4小时后才受到影响。当寄生虫在trtE治疗后感染宿主细胞时，这些效应是不可逆的。药物暴露超过4小时显著影响速殖子存活和改变寄生虫形态。trtE的作用机制尚不清楚，但包括阻断寄生虫入侵过程。需要进一步研究确定trtE的分子靶点，以进一步开发该化合物作为抗寄生虫候选药物。

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引用次数: 0

The faecal egg count reduction test: Will identification of larvae to species improve its utility? 粪卵计数减少试验：鉴定幼虫种类是否会提高其效用？

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-03-26 DOI: 10.1016/j.ijpddr.2025.100589

Dave Leathwick, Peter Green, Charlotte Bouchet, Alex Chambers, Tania Waghorn, Christian Sauermann

In the faecal egg count reduction test, visual identification of larvae cultured from faeces enables the egg counts to be apportioned to species/genera, resulting in a more accurate test. However, morphology cannot reliably differentiate some species meaning that, in some cases, efficacy can only be estimated at the genus or species-complex level. We investigated the benefits of identifying larvae to species using DNA to determine how often this would alter the diagnosis of resistance and whether increasing the number of larvae identified would alter the repeatability of an efficacy estimate.

Data on faecal nematode egg counts and the corresponding larval species mixes were acquired from tests conducted on commercial sheep farms. The proportion of each species present in faecal culture was determined using DNA. Efficacy was then compared for individual species and for those genera/species complexes which cannot reliably be differentiated visually. The proportion of each species present was subsequently resampled 10,000 times (repeated random sampling) and efficacy recalculated to produce the median efficacy, along with the 5 % and 95 % simulation percentiles. Subsequently, the number of larvae sampled to determine the species mix in each sample was varied from 50 to 6400 and the process repeated.

Of 152 comparisons of efficacy, 25 % of cases where genus-level identification resulted in a finding of ‘susceptible’ for that category, species-level identification returned at least one diagnosis of ‘resistant’ i.e., genus-level identification resulted in a 25 % false negative diagnosis.

When the number of larvae sampled for species identification was low (<400) variation in efficacy estimates was high, however, as sample size increased the confidence interval around the efficacy estimate decreased.

The results indicate that identifying large numbers of larvae to species using DNA has the potential to increase the accuracy and confidence in efficacy estimates achieved using the faecal egg count reduction test.

在粪便卵数减少试验中，从粪便中培养的幼虫的目视识别使卵数分配到物种/属，从而产生更准确的测试。然而，形态学不能可靠地区分某些物种，这意味着在某些情况下，功效只能在属或种复合水平上进行估计。我们研究了利用DNA鉴定幼虫对物种的益处，以确定这将改变耐药性诊断的频率，以及增加鉴定的幼虫数量是否会改变功效估计的可重复性。粪便线虫卵数和相应幼虫种类混合的数据是从在商业绵羊养殖场进行的试验中获得的。利用DNA测定粪便培养中存在的每种物种的比例。然后比较了单个物种和那些不能可靠地通过视觉区分的属/种复合物的功效。随后，每种存在的物种的比例重新采样10,000次（重复随机采样），并重新计算功效，以产生中位功效，以及5%和95%的模拟百分位数。随后，每个样本中取样的幼虫数量从50到6400不等，以确定物种混合，并重复该过程。在152个疗效比较中，25%的属级鉴定结果为该类别的“易感”病例，种级鉴定结果至少为一个“耐药”诊断，即属级鉴定结果为25%的假阴性诊断。当用于物种鉴定的幼虫数量较少时（<400），功效估计值的差异很大，然而，随着样本量的增加，功效估计值周围的置信区间减小。结果表明，利用DNA鉴定大量幼虫有可能提高使用粪卵计数减少试验获得的功效估计的准确性和可信度。

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引用次数: 0

A graphical user interface for wrmXpress 2.0 streamlines helminth phenotypic screening wrmXpress 2.0的图形用户界面简化了蠕虫表型筛选

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-03-20 DOI: 10.1016/j.ijpddr.2025.100588

Zachary Caterer , Rachel V. Horejsi , Carly Weber , Blake Mathisen , Chase N. Nelson , Maggie Bagatta , Ireland Coughlin , Megan Wettstein , Ankit Kulshrestha , Hui Siang Benjamin Lee , Leonardo R. Nunn , Mostafa Zamanian , Nicolas J. Wheeler

Image-based phenotypic screening is a fundamental technique used to better understand the basic biology of helminths and advance discovery of new anthelmintics. Miniaturization of screening platforms and automated microscopy have led to a surge in imaging data and necessitated software to organize and analyze these data. Traditionally, these analyses are performed remotely on high-performance computers, often requiring an understanding of a command line interface (CLI) and the ability to write scripts to control the software or job scheduler. Requiring access to specialized computing equipment and advanced computational skills raises the barrier to entry for these sorts of studies. The development of efficient, performant computer and graphical processing units for personal computers and cheaper imaging solutions has made the requirement of remote servers superfluous for many small to medium-scale screens, but most analytical software still require interaction with a CLI. To democratize the analysis of image-based phenotypic screens, we have developed a graphical user interface (GUI) for wrmXpress, a tool that integrates many popular computational pipelines for analyzing imaging data of parasitic and free-living worms. The GUI operates on any personal computer using the operating system's native web browser, allowing users to configure and run analyses using a point-and-click approach. Containerization of the application eliminates the need to install specialized programming libraries and dependencies, further increasing the ease of use. GUI development required a substantial reorganization of the wrmXpress backend codebase, which allowed for the addition of a new pipeline for high-resolution tracking of worm behavior, and we demonstrate its functionality by showing that praziquantel modulates the behavior of Schistosoma mansoni miracidia. These advances make cutting-edge analyses of image-based phenotyping of worms more equitable and accessible.

基于图像的表型筛选是一项基础技术，用于更好地了解蠕虫的基本生物学和推进新的驱虫剂的发现。筛选平台的小型化和自动化显微镜导致了成像数据的激增，需要软件来组织和分析这些数据。传统上，这些分析是在高性能计算机上远程执行的，通常需要理解命令行接口（CLI）并能够编写脚本来控制软件或作业调度器。需要使用专门的计算设备和先进的计算技能提高了进入这类研究的门槛。高效、高性能的计算机和用于个人计算机的图形处理单元以及更便宜的成像解决方案的发展，使得对许多中小型屏幕的远程服务器的需求变得多余，但是大多数分析软件仍然需要与CLI交互。为了使基于图像的表型筛选分析民主化，我们为wrmXpress开发了一个图形用户界面（GUI），该工具集成了许多流行的计算管道，用于分析寄生和自由生活蠕虫的成像数据。GUI可以在任何使用操作系统本地web浏览器的个人计算机上运行，允许用户使用指向和点击方法配置和运行分析。应用程序的容器化消除了安装专门的编程库和依赖项的需要，进一步提高了易用性。GUI开发需要对wrmXpress后端代码库进行大量重组，这允许添加一个新的管道，用于高分辨率跟踪蠕虫行为，我们通过显示吡喹酮调节马氏血吸虫的行为来证明其功能。这些进展使得基于图像的蠕虫表型分析更加公平和容易获得。

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引用次数: 0

Increased activity of CF3-derivatized levamisole at the ACC-2 receptor from the parasitic nematode Haemonchus contortus cf3衍生左旋咪唑在弯曲血蜱寄生线虫ACC-2受体上的活性增加

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-02-26 DOI: 10.1016/j.ijpddr.2025.100587

Autumn Collins , Sierra Varley , Tobias Clark , Nathan Chubb , Sean Forrester , Jean-Paul Desaulniers

The acetylcholine-gated chloride channel (ACC) family in parasitic nematodes represents a promising target for anthelmintic drug development. Levamisole, a widely known and utilized cholinergic agonist, has been used for decades to address many types of parasitic infections by targeting nematode nicotinic acetylcholine receptors (nAChRs) in nematodes. In this study, we report the synthesis and pharmacological evaluation of eight levamisole derivatives, five of which are novel, on the H. contortus ACC-2 receptor. This includes a CF₃-derivatized compound we have identified as compound 6 whose structure contains levamisole as a backbone with the addition of a 2-trifluoromethyl benzyl group. Electrophysiological assays revealed that compound 6 exhibited a five-fold increase in sensitivity (EC₅₀ 20 μM) compared to levamisole (EC₅₀ 100 μM), our parent compound, with an EC₅₀ comparable to that of acetylcholine (20 μM). Investigation of the in silico docking of compound 6 with H. contortus ACC-2 suggest that it interacts uniquely within the H. contortus ACC-2 binding pocket, which may contribute to its increased receptor sensitivity. These findings highlight the potential of structural modifications containing an electron-withdrawing group at the 2-position which can significantly enhance activity at the H. contortus ACC-2 receptor. This opens many avenues for the development of more effective treatments against parasitic nematodes, in an environment with increasing resistance.

寄生线虫的乙酰胆碱门控氯通道（ACC）家族为驱虫药开发提供了一个有前景的靶点。左旋咪唑是一种广泛使用的胆碱能激动剂，几十年来一直用于通过靶向线虫的烟碱乙酰胆碱受体（nAChRs）来治疗多种寄生虫感染。在这项研究中，我们报道了八种左旋咪唑衍生物的合成和药理学评价，其中五种是新的，对蛇麻ACC-2受体。这包括一个cf3衍生的化合物，我们已经确定为化合物6，它的结构包含左旋咪唑作为主链，外加一个2-三氟甲基苄基。电生理实验表明，化合物6的灵敏度（EC50 20 μM）是母体化合物左旋咪唑（EC50 100 μM）的5倍，EC50与乙酰胆碱（20 μM）相当。化合物6与H. contortus ACC-2的硅对接研究表明，它在H. contortus ACC-2结合口袋内独特地相互作用，这可能有助于其增加受体敏感性。这些发现突出了含有2位吸电子基团的结构修饰的潜力，可以显着增强H.扭曲ACC-2受体的活性。这为在耐药性日益增强的环境中开发更有效的治疗寄生线虫的方法开辟了许多途径。

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引用次数: 0

Recent in vitro advances in the ocular antimicrobial agents against Acanthamoeba 抗棘阿米巴眼用抗菌药物的体外研究进展

IF 4.1 2区医学 Q1 PARASITOLOGY

International Journal for Parasitology: Drugs and Drug Resistance

Pub Date : 2025-02-21 DOI: 10.1016/j.ijpddr.2025.100586

Chun-Hsien Chen , Jian-Ming Huang , Yu-Jen Wang , Chih-Ming Tsai , Wei-Chen Lin

This review examines the advancements in antimicrobial drug discovery with in vitro assays for Acanthamoeba, highlighting the efficacy of current topical antimicrobial agents. In recent decades, the treatment and diagnosis of Acanthamoeba keratitis (AK) have presented clinical challenges. Clinicians often rely on clinical judgment, risk factors, and patient travel history to guide initial treatment decisions. The clinical presentation of AK frequently coincides with bacterial and fungal keratitis, leading to delays in diagnostic confirmation. This review compiles a list of commonly used antimicrobial agents that may be useful in controlling and preventing Acanthamoeba and other microbial infections during the diagnostic waiting period. Due to their unique life cycle, consisting of both trophozoite and cyst stages, amoebae exhibit resistance to various clinical drugs. Current research efforts are focused on identifying alternative and effective treatment options. Despite the ongoing characterization of various cytocidal agents from natural and synthetic sources, chlorhexidine gluconate (CHG) and polyhexamethylene biguanide (PHMB) have emerged as the most effective therapies for AK. Drawing from previous studies, we catalog several commonly used antimicrobial agents that may enhance the efficacy of PHMB and CHG while also preventing other microbial infections. These alternative agents present promising options for treating AK cases. This review evaluates progress in anti-amoebic drug discovery, focusing on antibiotics and cataloging their activity at different stages of Acanthamoeba.

本文综述了棘阿米巴体外检测抗菌药物发现的进展，重点介绍了目前局部抗菌药物的疗效。近几十年来，棘阿米巴角膜炎（AK）的治疗和诊断提出了临床挑战。临床医生通常依靠临床判断、危险因素和患者旅行史来指导最初的治疗决定。AK的临床表现经常与细菌性和真菌性角膜炎相吻合，导致诊断确认的延误。本文综述了在诊断等待期控制和预防棘阿米巴和其他微生物感染可能有用的常用抗菌药物清单。由于其独特的生命周期，包括滋养体和囊肿阶段，变形虫表现出对各种临床药物的耐药性。目前的研究工作集中在确定替代和有效的治疗方案上。尽管各种天然和合成的细胞杀灭剂正在进行鉴定，葡萄糖酸氯己定（CHG）和聚六亚甲基二胍（PHMB）已成为治疗AK最有效的药物。根据以往的研究，我们列出了几种常用的抗菌药物，这些药物可以提高PHMB和CHG的疗效，同时也可以预防其他微生物感染。这些替代药物为治疗AK病例提供了有希望的选择。本文综述了抗阿米巴药物的发现进展，重点是抗生素和分类它们在棘阿米巴原虫不同阶段的活性。

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引用次数: 0