Resistance frequently arises when treating medulloblastoma (MB) patients with Vismodegib, markedly shortening their survival time. Consequently, the urgent problem to be solved is the discovery of a drug that can synergize with Vismodegib to improve its resistance in patients and enhance its efficacy. To validate the feasibility and efficacy of combining EZH2 (Enhancer of zeste homolog 2) inhibitor (EZH2i) with Vismodegib. A comprehensive assessment of their individual and combined effects on MB cell proliferation, migration, and invasion capabilities was conducted. The promising potential of EZH2i in inhibiting MB cell growth, migration and invasion was exhibited when used alone. Furthermore, when combined with Vismodegib, the inhibitory effect on MB was significantly potentiated. This synergy was further confirmed by SynergyFinder analysis, which revealed a remarkable highest single-agent score of 14.85 for the GSK126 and Vismodegib combination. Importantly, the enhanced efficacy of the combined EZH2i and Vismodegib therapy in suppressing tumor growth was also verified by the xenograft experiments in vivo. In summary, the combined use of EZH2i and Vismodegib demonstrated a remarkable synergistic effect in suppressing MB growth, presenting a promising treatment option for MB patients who had become resistant to Vismodegib.

Ubiquitylation, regulated by the ubiquitin-proteasome system (UPS), is crucial for cell division and cycle transitions in Toxoplasma gondii. However, the primary E1 ubiquitin-activating enzyme (UAE1) in this process has been unclear. This study identified and characterized TGGT1_290290 (TgUAE1) as the canonical E1 enzyme in T. gondii. Through a combination of bioinformatics, biochemical, pharmacological, and genetic approaches, TgUAE1 was shown to exhibit typical E1 activity, particularly in forming K48- and K63-linked polyubiquitin chains. TAK-243, a UAE1 inhibitor, can effectively inhibit the ubiquitin pathway in T. gondii, as thermal stabilization experiments identified TgUAE1 as its intracellular target. Disruption of TgUAE1 severely impaired parasite homeostasis and suppressed the lytic cycle, highlighting its critical role in T. gondii fitness. Mutation of C634 in TgUAE1 confirmed that its enzymatic activity is essential for function. Transcriptomics and quantitative ubiquitin proteomics revealed TgUAE1 as a key regulator of the ubiquitination process and the broader gene expression network in T. gondii. These findings not only underscore the indispensable role of TgUAE1 in the life cycle of T. gondii but also offer valuable data that could inform future studies on parasite biology and the development of novel therapeutic strategies.

Toxoplasma gondii, an intracellular parasitic protozoan, which infects almost all warm-blooded animals, including humans, causes toxoplasmosis. However, we lack effective drugs and vaccines to control toxoplasmosis, representing a clinical challenge. Therefore, safe and effective vaccines are urgently needed. In this study, a self-replicating mRNA vaccine comprising four T. gondii antigens: ROP18, TGME49_237490, TGME49_268230, and MIC13, named 4x-mRNA-LNP (lipid nanoparticle), was developed, and its protective efficacy was evaluated in mice. The expression of this vaccine in eukaryotic Human embryonic kidney 293 T (HEK-293 T) cells and mouse myoblast (C2C12) cells were analyzed, followed by enzyme-linked immunosorbent assay (ELISA) evaluation of the elicited humoral immune response. Subsequently, the vaccine-triggered immune responses in mice were detected, including antibody titers, T lymphocyte subsets, and cytokine levels. Finally, its immunoprotective effects were evaluated after challenging mice with T. gondii PRU oocysts or tachyzoites of different strains and analyzing the pathological changes, parasite loads, and mouse survival time. Western blotting and ELISA confirmed the successful eukaryotic expression and immunogenicity of 4x-mRNA, respectively. Statistical analyses, including the log-rank (Mantel–Cox) test, Student’s t-test, and one-way ANOVA, were performed using GraphPad Prism software. Mice vaccinated with 4x-mRNA-LNP generated higher levels of IgG1 and IgG2a antibodies (P < 0.05) and cytokines (IL-2, IL-4, IL-10, IL-12, IFN-γ) (P < 0.05) compared with the control group. The high specific IgG titer was maintained for at least 10 weeks after the last vaccination. The proportion of CD3+CD4+ T cells and CD3+CD8+ T cells also increased significantly (P < 0.05), along with increased spleen cell proliferation in 4x-mRNA-LNP-vaccinated mice. Notably, limited pathological changes and < 10 fg of parasites/mg were found in the immunized mice tissues post-pathogen challenge. During observation for 30 days, 4x-mRNA-LNP-immunized mice survived significantly longer under challenge with lethal doses of RH, ME49, or WH6 tachyzoites (survival rates = 60

Celastrol, a bioactive compound derived from the traditional Chinese herb Tripterygium wilfordii, has demonstrated various pharmacological properties, including anticancer effects. Medulloblastoma (MB), particularly the Sonic Hedgehog (SHH) subtype, remains a challenge due to its aggressive nature and limited therapeutic options. This study aims to investigate the inhibitory effects of celastrol on Sonic Hedgehog medulloblastoma (SHH-MB) cells in vitro and in vivo, focusing on its underlying mechanisms and signaling pathways. The effects of celastrol on cell proliferation were evaluated using the Cell Counting Kit-8 (CCK-8) assay, Ki-67 immunofluorescence staining, and colony formation assay. The scratch wound healing assay and transwell invasion assay were used to explore its effects on cell migration and invasion. An SHH-MB mouse xenograft model was constructed to assess the anti-cancer effect of celastrol. Flow cytometry was employed to detect the apoptotic effect and intracellular reactive oxygen species (ROS) levels, and Western blotting was used to analyze apoptosis-related proteins. In terms of mechanism exploration, through molecular reverse virtual screening, analysis of the medulloblastoma Gene Expression Omnibus (GEO) database, and transcriptomic analysis, it was speculated that celastrol might affect the PI3K-AKT pathway through TGFB2. Finally, Western blotting was used to verify the results related to this pathway. Celastrol significantly inhibited SHH-MB cell proliferation and induced apoptosis in both in vitro and in vivo models. Celastrol increased intracellular ROS levels, contributing to apoptosis, and effectively suppressed SHH-MB cell migration, invasion, and colony formation. Transcriptomic analysis revealed that celastrol downregulates TGF-beta2 and CXCL12 mRNA expression, potentially through the NF-κB signaling pathway, further supporting its antiproliferative effects. Celastrol demonstrates significant antitumor activity against SHH-MB by inducing ROS-mediated apoptosis and inhibiting proliferation, migration, and invasion. Its effects may involve suppression of the CXCL12/NF-κB signaling axis, providing a promising therapeutic strategy for SHH-MB treatment. Further research is warranted to explore its clinical applications.

ATG8/LC3-mediated autophagosome formation is a key rate-limiting step in the process of autophagy. The parasitic protist Toxoplasma gondii possesses a single ATG8 homolog (TgATG8), which can localize to either cytosolic autophagosome involved in delivery of autophagic material in bradyzoites, or the outermost membrane of apicoplast, a nonphotosynthetic plastid-like organelle, responsible for maintaining homeostasis in tachyzoites. However, mechanisms that regulate TgATG8 remain insufficiently understood. Here, a TgATG7 conditional knockdown line that we have generated is severely impaired in parasite's growth and exhibits significant defects in the organelle level, strikingly with a fragmentation of the mitochondrial network and a loss of the apicoplast. Specific TgATG7C1133S point mutant complemented line showed that these defects were associated with its E1-type enzyme activity. Both depletion of TgATG7 and mutation of its catalytic cysteine 1133 hindered TgATG8 lipidation and apicoplast localization. Unexpectedly, we also found that depletion of TgATG7 reduced the unlipidated TgATG8 protein level. Subsequently, we determined that TgATG7 was able to interact with TgATG8 directly via its C-terminal domain and multi-monoubiquitination stimulated proteasome-dependent degradation of TgATG8, while TgATG7 could inhibit the degradation through stabilization of TgATG8. Additionally, we identified a putative TgATG8 interacting fragment of TgATG7, 1281-1290aa. Depletion of the fragment impaired the parasite growth and apicoplast inheritance. To our knowledge, our study is the first to elucidate the role of TgATG7 and the ubiquitin-proteasome system in synergistically regulating the non-lipidated pool of TgATG8, suggesting a potential homeostatic mechanism responsible for balancing autophagic activity in T. gondii.

IntroductionWild rodents are key hosts for Cryptosporidium transmission, yet there is a dearth of information regarding their infection status in the Inner Mongolian Autonomous Region and Liaoning Province of China. Therefore, the present study was conducted to determine the prevalence and genetic characteristics of Cryptosporidium among wild rodents residing in these two provinces.MethodsA total of 486 rodents were captured, and fresh feces were collected from each rodent’s intestine for DNA extraction. Species identification of rodents was performed through PCR amplification of the vertebrate cytochrome b (cytb) gene. To detect the presence of Cryptosporidium in all fecal samples, PCR analysis and sequencing of the partial small subunit of the ribosomal RNA (rRNA) gene were performed.ResultsFour species of rodents were identified: Rattus norvegicus, Mus musculus, Apodemus agrarius, and Cricetulus barabensis. Positive results for Cryptosporidium were obtained for 9.2% (18/195), 6.6% (7/106), 5.6% (5/89), and 6.3% (6/96) of these rodents, respectively, with an average infection rate of 7.4% (36/486). The identification revealed the presence of five Cryptosporidium species, C. ubiquitum (n = 8), C. occultus (n = 5), C. muris (n = 2), C. viatorum (n = 1), and C. ratti (n = 1), along with two Cryptosporidium genotypes: Rat genotype III (n = 10) and Rat genotype IV (n = 9).DiscussionBased on the molecular evidence presented, the wild rodents investigated were concurrently infected with zoonotic (C. muris, C. occultus, C. ubiquitum and C. viatorum) as well as rodent-adapted (C. ratti and Rat genotype III and IV) species/genotypes, actively participating in the transmission of cryptosporidiosis.

Wild rodents are key carriers of various human pathogens, including Blastocystis spp. Our study aimed to assess the prevalence and genetic characteristics of Blastocystis among wild rodents in the Inner Mongolian Autonomous Region and Liaoning Province of China. From November 2023 to February 2024, 486 rodents were captured in these regions. Fresh feces were collected from the intestines of each rodent for the isolation of DNA and PCR amplification of the vertebrate cytochrome b (cytb) gene to identify rodent species. Subsequently, PCR analysis and sequencing of the partial small subunit of the ribosomal RNA (rRNA) gene were utilized to detect Blastocystis in all fecal samples. Of the total samples, 27.4% (133/486) were found to be Blastocystis positive. The results revealed the presence of four species of rodents infected with Blastocystis, 32.3% (63/195) in Rattus norvegicus, 15.1% (16/106) in Mus musculus, 20.2% (18/89) in Apodemus agrarius, and 37.5% (36/96) in Cricetulus barabensis. Sequence analysis confirmed the existence of five Blastocystis subtypes: ST1 (n = 4), ST2 (n = 2), the ST4 (n = 125, the dominant subtype), ST10 (n = 1), and a novel ST (n = 1). The identified zoonotic subtypes (ST1, ST2, ST4, and ST10) highlight the possible role played by wild rodents in the transmission of Blastocystis to humans, thereby elevating the chances of human infection. Meanwhile, the discovery of novel sequences also provides new insights into the genetic diversity of this parasite.

Medulloblastoma (MB) is the most common malignant brain tumor in children. Within MB, tumors driven by the Sonic Hedgehog (SHH) pathway represent the most heterogeneous subtype, known as SHH subtype medulloblastoma (SHH-MB). Tenovin-6, a recognized p53 activator, has been demonstrated to inhibit autophagy and modulate sirtuin activity, underscoring its potential as a novel therapeutic agent across various malignancies. However, its efficacy in treating SHH-MB remains unexplored. This study aims to investigate the inhibitory effects of tenovin-6 on SHH-MB and elucidate its underlying signaling pathways. We assessed the impact of tenovin-6 on cell proliferation through the CCK-8 and colony formation assays. The scratch and transwell invasion assays were utilized to evaluate the drug's effects on metastasis. Apoptosis and reactive oxygen species (ROS) levels were measured using flow cytometry. Potential signaling pathways were identified via transcriptomics and quantitative PCR (qPCR). Our in vivo studies involved a mouse xenograft model to explore tenovin-6's anticancer efficacy against SHH-MB. The findings indicate that tenovin-6 not only inhibits cell proliferation and metastasis in SHH-MB cell lines but also promotes apoptosis, which is closely linked to its proliferation-inhibiting properties. Additionally, animal experiments confirmed that tenovin-6 suppresses MB growth in vivo. We discovered that tenovin-6 reduces intracellular ROS levels and inhibits autophagy in SHH-MB by disrupting the fusion of autophagosomes with lysosomes, likely through inducing autophagosome formation.

We investigated the contaminations of phthalates (PAEs), organophosphate esters (OPEs), and polycyclic aromatic hydrocarbons (PAHs) in the vegetables and their corresponding soils from 26 plastic greenhouses of Northeast China. PAEs, OPEs, and PAHs in the edible portion of vegetables were in the range of 2620-21800, 115-852, and 32.4-602 ng/g, while the levels of these chemicals in the greenhouse soils were 5770-18800, 196-935, and 109-1600 ng/g, respectively. PAEs are the main organic pollutants in greenhouses, which were 1-2 orders of magnitude higher than that of OPEs and PAHs. Leafy vegetables showed the highest contamination level, which is ∼1-3 times that of root and fruit vegetables. Bioaccumulation factors (BAFs) of chemicals are significantly negatively correlated with their physicochemical properties, e.g., octanol-water partition coefficient and organic carbon partition coefficient. The partition-limited model can accurately predict the contamination level of greenhouse vegetables to a certain extent based on the chemical's concentration in the corresponding soil. We assessed the hazard quotients of target compounds through daily intake of greenhouse vegetables, and found a low risk for di(2-ethylhexyl) phthalate. This research emphasized the potential dietary exposure risks caused by greenhouse leafy vegetables, and proposed a method for evaluating the risk of greenhouse vegetables through soil monitoring.

IntroductionWild rodents can serve as reservoirs or carriers of E. bieneusi, thereby enabling parasite transmission to domestic animals and humans. This study aimed to investigate the prevalence of E. bieneusi in wild rodents from the Inner Mongolian Autonomous Region and Liaoning Province of China. Moreover, to evaluate the potential for zoonotic transmission at the genotype level, a genetic analysis of the isolates was performed.MethodsA total of 486 wild rodents were captured from two provinces in China. Polymerase chain reaction (PCR) was performed to amplify the vertebrate cytochrome b (cytb) gene in the fecal DNA of the rodents to detect their species. The genotype of E. bieneusi was determined via PCR amplification of the internal transcribed spacer (ITS) region of rDNA. The examination of genetic characteristics and zoonotic potential requires the application of similarity and phylogenetic analysis.ResultsThe infection rates of E. bieneusi in the four identified rodent species were 5.2% for Apodemus agrarius (n = 89), 4.5% for Cricetulus barabensis (n = 96), 11.3% for Mus musculus (n = 106), and 38.5% for Rattus norvegicus (n = 195). Infection was detected at an average rate of 17.4% among 486 rodents. Of the 11 identified genotypes, nine were known: SHR1 (detected in 32 samples), D (30 samples), EbpA (9 samples), PigEbITS7 (8 samples), HNR-IV (6 samples), Type IV (5 samples), HNR-VII (2 samples), HNH7 (1 sample), and HNPL-V (1 sample). Two novel genotypes were also discovered, NMR-I and NMR-II, each comprising one sample. The genotypes were classified into group 1 and group 13 via phylogenetic analysis.DiscussionBased on the initial report, E. bieneusi is highly prevalent and genetically diverse in wild rodents residing in the respective province and region. This indicates that these animals are crucial for the dissemination of E. bieneusi. Zoonotic E. bieneusi-carrying animals present a significant hazard to local inhabitants. Therefore, it is necessary to increase awareness regarding the dangers presented by these rodents and reduce their population to prevent environmental contamination.

Toxoplasmosis, a zoonotic parasitic disease caused by Toxoplasma gondii (T. gondii), is prevalent worldwide. The fact should be emphasized that a considerable proportion of individuals infected with T. gondii may remain asymptomatic; nevertheless, the condition can have severe implications for pregnant women or immunocompromised individuals. The current treatment of toxoplasmosis primarily relies on medication; however, traditional anti-toxoplasmosis drugs exhibit significant limitations in terms of efficacy, side effects, and drug resistance. The life cycles of T. gondii are characterized by distinct stages and its body morphology goes through dynamic alterations during the growth cycle that are intricately governed by a wide array of post-translational modifications (PTMs). Ubiquitin (Ub) signaling and ubiquitin-like (Ubl) signaling are two crucial post-translational modification pathways within cells, regulating protein function, localization, stability, or interactions by attaching Ub or ubiquitin-like proteins (Ubls) to target proteins. While these signaling mechanisms share some functional similarities, they have distinct regulatory mechanisms and effects. T. gondii possesses both Ub and Ubls and plays a significant role in regulating the parasite's life cycle and maintaining its morphology through PTMs of substrate proteins. Investigating the role and mechanism of protein ubiquitination in T. gondii will provide valuable insights for preventing and treating toxoplasmosis. This review explores the distinctive characteristics of Ub and Ubl signaling in T. gondii, with the aim of inspiring research ideas for the identification of safer and more effective drug targets against toxoplasmosis.

Background Cryptosporidium is a protozoan parasite causing diarrhoea in humans and animals. Although Cryptosporidium has been found in domestic horses (farmed or kept at pasture), there has been only one published study of Cryptosporidium infections in Chinese racehorses, which was restricted to a very small geographical area. Objectives To investigate the presence of Cryptosporidium spp. in the faeces of racehorses in China and to perform molecular characterisation of the parasite. Study design Cross-sectional. Methods A total of 621 fresh faecal samples were collected for DNA extraction from racehorses at 17 equestrian clubs from 12 provinces of China from December 2016 to May 2018. All the DNA were analysed for the presence of Cryptosporidium species/genotypes and subtypes by PCR amplification of the small subunit ribosomal RNA and 60 kDa glycoprotein genes respectively. Results PCR analysis revealed that 11 samples (1.8%) were positive for Cryptosporidium spp. Among them seven samples were identified as C. parvum and four were C. hominis. The C. parvum isolates were identified as subtype IIdA14G1 (n = 4) and IIdA15G1 (n = 3), while all C. hominis isolates were identified as subtype IkA18G1 (n = 4). Main limitations A single faecal sample from each horse was used instead of multiple samples that could improve the detection rates of the parasite. Conclusions Although Cryptosporidium infection rate was relatively low in the investigated racehorses, the presence of zoonotic subtypes IIdA14G and 1IIdA15G1 of C. parvum and IkA18G1 of C. hominis, suggesting that these animals are a potential source of Cryptosporidium in humans.

BACKGROUND:Glioma is the most malignant primary brain tumor with a poor survival time. The tumour microenvironment, especially glioma-associated microglia/macrophages (GAMs), plays an important role in the pathogenesis of glioma. Currently, microglia (CD11b+/CD45Low) and macrophages (CD11b+/CD45High) are distinguished as distinct cell types due to their different origins. Moreover, signal-transducing adaptor protein 1 (STAP1) plays a role in tumourigenesis and immune responses. However, to date, no studies have been reported on STAP1 in GAMs.METHODS:The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases were used to investigate the association between STAP1 mRNA levels and clinical parameters (grades, mutations in isocitrate dehydrogenase, and overall survival). RNA-sequencing, qRT-PCR, Western blotting, immunohistochemistry and immunofluorescence analyses were performed to detect the expression level of STAP1 and related proteins. BV-2 cells were used to construct a STAP1-overexpressing cell line. Phagocytosis of BV-2 cells was assessed by flow cytometry and fluorescence microscopy. C57BL/6 mice were used to establish orthotopic and subcutaneous glioma mouse models. Glioma growth was monitored by bioluminescence imaging.RESULTS:STAP1 expression in glioma-associated microglia is positively correlated with the degree of malignancy and poor prognosis of glioma. Moreover, STAP1 may promote M2-like polarisation by increasing ARG1 expression and inhibiting microglial phagocytosis of microglia. Increased ARG1 may be associated with the IL-6/STAT3 pathway. Impaired phagocytosis may be associated with decreased cofilin and filopodia.CONCLUSION:STAP1 is positively associated with the degree of glioma malignancy and may represent a potential novel therapeutic target for glioma.

The mitochondrial electron transport chain (ETC) of apicomplexan parasites differs considerably from the ETC of the animals that these parasites infect, and is the target of numerous anti-parasitic drugs. The cytochrome c oxidase complex (Complex IV) of the apicomplexan Toxoplasma gondii ETC is more than twice the mass and contains subunits not found in human Complex IV, including a 13 kDa protein termed TgApiCox13. TgApiCox13 is homologous to a human iron-sulfur (Fe-S) cluster-containing protein called the mitochondrial inner NEET protein (HsMiNT) which is not a component of Complex IV in humans. Here, we establish that TgApiCox13 is a critical component of Complex IV in T. gondii, required for complex activity and stability. Furthermore, we demonstrate that TgApiCox13, like its human homolog, binds two Fe-S clusters. We show that the Fe-S clusters of TgApiCox13 are critical for ETC function, having an essential role in mediating Complex IV integrity. Our study provides the first functional characterisation of an Fe-S protein in Complex IV.

We investigated the occurrence and genotypic diversity of E. bieneusi in farmed Asiatic brush-tailed porcupines and bamboo rats from Hainan Province, China. Four hundred and sixty-seven fresh feces were collected from 164 Asiatic brush-tailed porcupines and 303 bamboo rats. DNA extraction from the feces and genotyping of E. bieneusi were performed by the amplification of the internal transcribed spacer (ITS) region of rDNA of E. bieneusi using PCR. A neighbor-joining tree was constructed based on the sequences obtained here and other sequences of E. bieneusi genotypes stored in Genbank. The total rate of infection with E. bieneusi was 32.5% (152/467), with 14.6% (24/164) in Asiatic brush-tailed porcupines and 42.2% (128/303) in bamboo rats infected. Seventeen genotypes of E. bieneusi were identified including 12 known genotypes, i.e., D (n = 78), Henan-III (n = 21), SHW7 (n = 19), KIN-1 (n = 11), ETMK5 (n = 7), TypeIV (n = 4), EbpD (n = 2), EbpA (n = 1), EbpC (n = 1), S7 (n = 1), HNPL-III (n = 1), HNR-VII (n = 1), and five novel genotypes named as HNZS-I (n = 1) and HNHZ-I to HNHZ-IV (n = 1 per genotype). Phylogenetic analysis revealed that all the genotypes found here except genotype S7 fell into Group 1. The present study demonstrated a relatively high prevalence of E. bieneusi infection (32.5%) and a large genetic variation of E. bieneusi (seventeen genotypes) in farmed Asiatic brush-tailed porcupines and bamboo rats in Hainan, China. The high proportion (78.3%) of zoonotic genotypes identified in the animals investigated here suggests that there is the potential for zoonotic or cross-species transmission which may pose a serious public health threat in the area. Public education on the management of Asiatic brush-tailed porcupines and bamboo rats should be implemented in the investigated areas.

BackgroundToxoplasmosis caused by Toxoplasma gondii is a globally distributed zoonosis. Most infections appear asymptomatic in immunocompetent individuals, but toxoplasmosis can be fatal in fetuses and immunocompromised adults. There is an urgent need to research and develop effective and low-toxicity anti-T. gondii drugs because of some defects in current clinical anti-T. gondii drugs, such as limited efficacy, serious side effects and drug resistance.MethodsIn this study, 152 autophagy related compounds were evaluated as anti-T. gondii drugs. The activity of β-galactosidase assay based on luminescence was used to determine the inhibitory effect on parasite growth. At the same time, MTS assay was used to further detect the effects of compounds with over 60% inhibition rate on host cell viability. The invasion, intracellular proliferation, egress and gliding abilities of T. gondii were tested to assess the inhibitory effect of the chosen drugs on the distinct steps of the T. gondii lysis cycle.ResultsThe results showed that a total of 38 compounds inhibited parasite growth by more than 60%. After excluding the compounds affecting host cell activity, CGI-1746 and JH-II-127 were considered for drug reuse and further characterized. Both CGI-1746 and JH-II-127 inhibited tachyzoite growth by 60%, with IC50 values of 14.58 ± 1.52 and 5.88 ± 0.23 μM, respectively. TD50 values were 154.20 ± 20.15 and 76.39 ± 14.32 μM, respectively. Further research found that these two compounds significantly inhibited the intracellular proliferation of tachyzoites. Summarize the results, we demonstrated that CGI-1746 inhibited the invasion, egress and especially the gliding abilities of parasites, which is essential for the successful invasion of host cells, while JH-II-127 did not affect the invasion and gliding ability, but seriously damaged the morphology of mitochondria which may be related to the damage of mitochondrial electron transport chain.DiscussionTaken together, these findings suggest that both CGI-1746 and JH-II-127 could be potentially repurposed as anti-T. gondii drugs, lays the groundwork for future therapeutic strategies.

Blastocystis sp. is an important gastrointestinal parasite with global distribution, prevalent in humans, farmed animals, and wildlife. Therefore, this study aimed to investigate the prevalence and genetic diversity of Blastocystis sp. in Asiatic brush-tailed porcupines (Atherurus macrourus), bamboo rats (Rhizomys pruinosus), and masked palm civets (Paguma larvata) in Hainan Province, China. A total of 900 fecal samples were collected from three farmed animal species including 257 porcupines, 360 rats, and 283 civets. Genomic DNA was extracted from each fecal sample and Blastocystis sp. was detected by PCR at the small subunit ribosomal RNA (SSU rRNA) gene. A phylogenetic tree was constructed using the maximum likelihood method. Blastocystis sp. was detected in 47 (5.2%) fecal samples: 12 (4.7%) Asiatic brush-tailed porcupines, 8 (2.2%) bamboo rats, and 27 (9.5%) masked palm civets. Three known Blastocystis sp. subtypes, including ST1, ST4, ST5, and one unnamed subtype (unST), were found in one, 19, 26, and one animal, respectively. Subtypes ST4 and unST were detected in porcupines, ST4 in rats, and ST1 and ST5 in civets. Our results suggest that the three farmed animal species reported in this study could serve as reservoirs for potentially zoonotic Blastocystis sp. subtypes and transmit this parasite to humans, other farmed animals, and wildlife.

目的:研究miR-145与心肌素(MyoCD)对人主动脉血管平滑肌细胞(VSMCs)脂质蓄积的影响.方法:ox-LDL孵育细胞,油红O染色观察细胞成脂,ELISA检测细胞内胆固醇含量;miR-145 siRNA及MyoCD过表达观察miR-145和MyoCD对血管平滑肌细胞脂质蓄积的影响,荧光定量PCR检测三磷酸腺苷结合盒转运体(ABCA)1的表达.结果:与对照组相比,MyoCD过表达组MyoCD蛋白及mRNA表达量均明显升高(P<0.05),miR-145 inhibitor组miR-145表达量下调(P<0.05).ELISA检测结果表明,与空载+miR-145 inhibitor组相比,miR-145通过MyoCD过表达降低胆固醇含量.油红O染色结果显示,与空载组相比,抑制miR-145以及MyoCD+miR-145 inhibitor组均可使细胞内脂滴数量较少.PCR结果显示,抑制miR-145对ABCA1水平无显著影响.结论:miR-145低表达和MyoCD过表达可抑制VSMC细胞脂质蓄积.

Background: Lysine lactylation (Kla) is a novelposttranslational modification (PTM) identified in histone and nonhistone proteins of several eukaryotic cells that directly activates gene expression and DNA replication. However, very little is known about the scope and cellular distribution of Kla in apicomplexan parasites despite its significance in public and animal health care. Methods: Toxoplasma gondii, the causative agent of toxoplasmosis, is an obligate intracellular apicomplexan parasite that can infect different nucleated cell types of animals and humans. We used this parasite as a model organism and extracted the total protein of tachyzoites to produce the first global lysine lactylome profile of T. gondii through liquid chromatography-tandem mass spectrometry. We also investigated the level and localization of the Kla protein in T. gondii using western blotting and the indirect fluorescent antibody test (IFA), respectively. Results: A total of 983 Kla sites occurring on 523 lactylated proteins were identified in the total protein extracted from Toxoplasma tachyzoites, the acute toxoplasmosis-causing stage. Bioinformatics analysis revealed that the lactylated proteins were evolutionarily conserved and involved in a wide variety of cellular functions, such as energy metabolism, gene regulation and protein biosynthesis. Subcellular localization analysis and IFA results further revealed that most of the lactylated T. gondii proteins were localized in the nucleus, indicating the potential impact of Kla on gene regulation in the T. gondii model. Notably, an extensive batch of parasite-specific proteins unique to phylum Apicomplexa is lactylated in T. gondii. Conclusions: This study revealed that Kla is widespread in early dividing eukaryotic cells. Lactylated proteins, including a batch of unique parasite proteins, are involved in a remarkably diverse array of cellular functions. These valuable data will improve our understanding of the evolution of Kla and potentially provide the basis for developing novel therapeutic avenues.

The apicoplast, which harbors key pathways involved in biosynthesis of vital metabolites, is a unique and essential nonphotosynthetic plastid organelle in apicomplexan parasites. Intriguingly, autophagy-related protein 8 (Atg8), a highly conserved eukaryotic protein, can localize to the outermost membrane of the apicoplast and modulate its inheritance in both Toxoplasma and Plasmodium parasites. The Atg8-Atg3 interaction plays a key role in Atg8 lipidation and localization, and our previously work in Toxoplasma has suggested that the core Atg8-family interacting motif (AIM) in TgAtg3, 239FADI242, and the R27 residue of TgAtg8 contribute to TgAtg8-TgAtg3 interaction in vitro. However, little is known about the function of this interaction or its importance in tachyzoite growth in Toxoplasma gondii. Here, we generated two complemented cell lines, TgAtg3F239A/I242A and TgAtg8R27E, based on the TgAtg3 and TgAtg8 conditional knockdown cell lines, respectively. We found that both mutant complemented cell lines were severely affected in terms of tachyzoite growth and displayed delayed death upon conditional knockdown of endogenous TgAtg3 or TgAtg8. Intriguingly, both complemented lines appeared to be defective in TgAtg8 lipidation and apicoplast inheritance. Moreover, we showed that the interaction of TgAtg8 and TgAtg3 is critical for TgAtg8 apicoplast localization. In addition, we found that the TgAtg3F239A/I242A complemented line exhibits an integral mitochondrial network upon ablation of endogenous TgAtg3, which is distinct from TgAtg3-depleted parasites with a fragmented mitochondrial network. Taken together, this work solidifies the contribution of the TgAtg8-TgAtg3 interaction to apicoplast inheritance and the growth of T. gondii tachyzoites. IMPORTANCEToxoplasma gondiiis a widespread intracellular parasite infecting a variety of warm-blooded animals, including humans. Current frontline treatment of toxoplasmosis suffers many drawbacks, including toxicity, drug resistance, and failure to eradicate tissue cysts, underscoring the need to identify novel drug targets for suppression or treatment of toxoplasmosis. TgAtg8 is thought to serve multiple functions in lipidation and is considered essential to the growth and development of both tachyzoites and bradyzoites. Here, we show that Toxoplasma gondii has adapted a conserved Atg8-Atg3 interaction, required for canonical autophagy in other eukaryotes, to function specifically in apicoplast inheritance. Our finding not only highlights the importance of TgAtg8-TgAtg3 interaction in tachyzoite growth but also suggests that this interaction is a promising drug target for the therapy of toxoplasmosis.