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Cao X, Huang M, Ma Y, Song X, Hu D. In vitro anti-Toxoplasma gondii effects of a coccidiostat dinitolmide. Vet Parasitol 2023; 316:109903. [PMID: 36871500 DOI: 10.1016/j.vetpar.2023.109903] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 03/06/2023]
Abstract
Coccidiosis, caused by Eimeria species, results in huge economic losses to the animal industry. Dinitolmide, a veterinary-approved coccidiostat, has a wide anticoccidial spectrum with no effect on host immunity. However, the mechanism of its anticoccidial effects remains unclear. Here, we used an in vitro culture system of T. gondii to explore the anti-Toxoplasma effect of dinitolmide and its underlying mechanism against coccidia. We show that dinitolmide has potent in vitro anti-Toxoplasma activity with the half-maximal effective concentration (EC50) of 3.625 µg/ml. Dinitolmide treatment significantly inhibited the viability, invasion and proliferation of T. gondii tachyzoites. The recovery experiment showed that dinitolmide can completely kill T. gondii tachyzoites after 24 h of treatment. Morphologically abnormal parasites were observed after dinitolmide exposure, including asynchronous development of daughter cells and deficiency of parasite inner and outer membrane. Further electron microscopy results showed that the drug could damage the membrane structure of T. gondii. By comparative transcriptomic analysis, we found that genes related to cell apoptosis and nitric-oxide synthase were up-regulated after dinitolmide treatment, which might be responsible for parasite cell death. Meanwhile, many Sag-related sequence (srs) genes were down-regulated after treatment, which could be closely associated with the reduction of parasite invasion and proliferation capacity. Our study indicates that the coccidiostat dinitolmide has a potent inhibitory effect on T. gondii in vitro and provides insight into the mode of action of the drug.
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Affiliation(s)
- Xinru Cao
- Key Laboratory of Prevention and Control for Animal Disease, College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Mao Huang
- Key Laboratory of Prevention and Control for Animal Disease, College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Yazhen Ma
- Key Laboratory of Prevention and Control for Animal Disease, College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Xingju Song
- Key Laboratory of Prevention and Control for Animal Disease, College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Dandan Hu
- Key Laboratory of Prevention and Control for Animal Disease, College of Animal Science and Technology, Guangxi University, Nanning, China.
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2
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Zhang H, Zhang L, Si H, Liu X, Suo X, Hu D. Early Transcriptional Response to Monensin in Sensitive and Resistant Strains of Eimeria tenella. Front Microbiol 2022; 13:934153. [PMID: 35859739 PMCID: PMC9289555 DOI: 10.3389/fmicb.2022.934153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/07/2022] [Indexed: 11/13/2022] Open
Abstract
Eimeria parasites are the causative agents of coccidiosis, a common parasitic disease in poultry and livestock that causes significant economic losses to the animal husbandry industry. Ionophore coccidiostats, such as monensin and salinomycin, are widely used for prophylaxis of coccidiosis in poultry. Unfortunately, widespread drug resistance has compromised their efficacy. As a result, there is an increasing need to understand the targets and resistance mechanisms to anticoccidials. However, how Eimeria parasite genes respond to ionophores remains unclear. In this study, resistance to monensin was induced in E. tenella through serial generations of selection. Both sensitive and resistant E. tenella sporozoites were treated with 5 μg/ml monensin for 0, 2, and 4 h, respectively. Gene transcription profiles were then compared by high-throughput sequencing. The results showed that protein translation-related genes were significantly downregulated after drug induction. A total of 1,848 DEGs were detected in the sensitive strain after 2 h of exposure, whereas only 31 were detected in the resistant strain. Among these DEGs in the sensitive strain, genes associated with protein degradation were significantly upregulated, supporting the autophagy-like parasite killing theory. Then, 4 h of exposure resulted in additional 626 and 621 DEGs for sensitive and resistant strains, respectively. This result implies that the gene transcription in sensitive strain is more susceptible to monensin treatment. Our results provide gene expression landscapes of E. tenella following monensin treatment. These data will contribute to a better understanding of the mechanism of drug resistance to polyether ionophores in coccidia.
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Affiliation(s)
- Hongtao Zhang
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Lei Zhang
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Hongbin Si
- College of Animal Science and Technology, Guangxi University, Nanning, China
| | - Xianyong Liu
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Xun Suo
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Dandan Hu
- College of Animal Science and Technology, Guangxi University, Nanning, China
- *Correspondence: Dandan Hu
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Combinatorial Effect of Dietary Oregano Extracts and 3,4,5-Trihydroxy Benzoic Acid on Growth Performance and Elimination of Coccidiosis in Broiler Chickens. J Poult Sci 2022; 59:233-246. [PMID: 35989693 PMCID: PMC9346594 DOI: 10.2141/jpsa.0210116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/24/2021] [Indexed: 11/21/2022] Open
Abstract
We aimed to compare the combinatorial effect of 3,4,5-trihydroxybenzoic acid (THB) and oregano extracts (OE) with THB alone on the growth performance and elimination of deleterious effects in coccidiosis-infected broilers. A total of 210 one-day-old broilers were randomly assigned to one of five dietary treatments, with six replicates each, for 35 days. Dietary treatments were: 1) non-challenged, non-treated (NC); 2) challenged, non-treated (PC); 3) PC+ Salinomycin (0.05 g/kg; AB); 4) PC+THB (0.1 g/kg; THB); and 5) PC+THB+OE (0.1 g/kg; COM). On day 14, all groups except for NC were challenged with a 10-fold dose of Livacox® T anticoccidial vaccine to induce mild coccidiosis. All treatments significantly improved (P<0.05) body weight, average daily gain, and average daily feed intake, compared to PC, on days 21, 28, and 35. However, all treatments significantly reduced (P<0.05) the feed conversion ratio of PC by more than 14.60% on day 35, 11.76% during growing period, and 10.36% through the entire period. Broilers receiving anticoccidial treatments had 54.23% and 51.86% lower lesion scores (P<0.05) at 4 and 7 days post-infection, respectively, compared to PC. Additionally, the villus height of COM was significantly longer (P < 0.05) than that of THB. Although the molecular action of COM remains unclear, OE addition to THB reduced the shedding of oocysts better than THB alone (P<0.05, 9-11 days post-infection). Most importantly, COM effectively minimized the mortality of challenged birds from as high as 11.90% (PC) to 0%, a level similar to NC and AB, while THB maintained a mortality of 2.38%. In conclusion, the anticoccidial effect of THB can be enhanced by the addition of OE for better animal performance and the elimination of deleterious effects from coccidiosis-infected broilers for 35 days.
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Wu RZ, Zhou HY, Song JF, Xia QH, Hu W, Mou XD, Li X. Chemotherapeutics for Toxoplasma gondii: Molecular Biotargets, Binding Modes, and Structure-Activity Relationship Investigations. J Med Chem 2021; 64:17627-17655. [PMID: 34894691 DOI: 10.1021/acs.jmedchem.1c01569] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Toxoplasmosis, an infectious zoonotic disease caused by the apicomplexan parasite Toxoplasma gondii (T. gondii), is a major worldwide health problem. However, there are currently no effective options (chemotherapeutic drugs or prophylactic vaccines) for treating chronic latent toxoplasmosis infection. Accordingly, seeking more effective and safer chemotherapeutics for combating this disease remains a long-term and challenging objective. In this paper, we summarize possible molecular biotargets, with an emphasis on those that are druggable and promising, including, without limitation, calcium-dependent protein kinase 1, bifunctional thymidylate synthase-dihydrofolate reductase, and farnesyl diphosphate synthase. Meanwhile, as important components of medicinal chemistry, the binding modes and structure-activity relationship profiles of the corresponding inhibitors were also illuminated. We anticipate that this information will be helpful for further identification of more effective chemotherapeutic interventions to prevent and treat zoonotic infections caused by T. gondii.
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Affiliation(s)
- Rong-Zhen Wu
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China
| | - Huai-Yu Zhou
- Department of Pathogen Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, no. 44 Wenhua Xi Road, Ji'nan, Shandong 250012, PR China
| | - Jing-Feng Song
- School of Pharmaceutical Sciences and Yunnan Provincial Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, no. 1168 Chunrong Xi Road, Kunming, Yunnan 650500, PR China
| | - Qiao-Hong Xia
- Department of Pathogen Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, no. 44 Wenhua Xi Road, Ji'nan, Shandong 250012, PR China
| | - Wei Hu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, no. 72 Binhai Road of JiMo, Qingdao, Shandong 266237, PR China
| | - Xiao-Dong Mou
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China
| | - Xun Li
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China.,Key Laboratory of Forensic Toxicology, Ministry of Public Security, Beijing 100192, PR China
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Leesombun A, Nihei CI, Kondoh D, Nishikawa Y. Polyether ionophore kijimicin inhibits growth of Toxoplasma gondii and controls acute toxoplasmosis in mice. Parasitol Res 2021; 121:413-422. [PMID: 34750652 DOI: 10.1007/s00436-021-07363-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 10/26/2021] [Indexed: 11/28/2022]
Abstract
The natural polyether ionophore antibiotics may be important chemotherapeutic agents. Among them, kijimicin represents an important type of ionophore compound because it inhibits Eimeria tenella and human immunodeficiency virus. The ionophore monensin displays potent activities against several coccidian parasites including the opportunistic pathogen of humans, Toxoplasma gondii. At first, we evaluated the anti-Toxoplasma activity of kijimicin, monensin as a reference control, and anti-Toxoplasma drugs such as clindamycin, in vitro. The half inhibitory concentrations (IC50) for the anti-Toxoplasma activities of kijimicin, monensin, and clindamycin were 45.6 ± 2.4 nM, 1.3 ± 1.8 nM, and 238.5 ± 1.8 nM, respectively. Morphological analyses by electron microscopy revealed cellular swelling and multiple intracellular vacuole-like structures in the T. gondii tachyzoites after treatment with kijimicin and monensin. Kijimicin and monensin also inhibited the invasion of extracellular parasites (IC50 = 216.6 ± 1.9 pM and 531.1 ± 1.9 pM, respectively). Importantly, kijimicin treatment resulted in decreased mitochondrial membrane potential and generation of reactive oxygen species in T. gondii as monensin did. Furthermore, mice treated with kijimicin at 10 mg/kg/day and 3 mg/kg/day showed 91.7% and 66.7% survival rates, respectively, 30 days after infection with T. gondii. The control mice all died within 18 days of infection. The present study shows that kijimicin inhibits T. gondii growth and changes the ultrastruct of the parasites. This finding may lead to validation of kijimicin as new drug to control T. gondii growth.
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Affiliation(s)
- Arpron Leesombun
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.,Department of Pre-Clinic and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, 999 Phutthamonthon Sai 4 Road, Salaya, 73170, Phutthamonthon Nakhonpathom, Thailand
| | - Coh-Ichi Nihei
- The Institute of Microbial Chemistry, Microbial Chemistry Research Foundation (BIKAKEN), Tokyo, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo, 141-0021, Japan
| | - Daisuke Kondoh
- Division of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan
| | - Yoshifumi Nishikawa
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
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Boromycin Has Potent Anti- Toxoplasma and Anti- Cryptosporidium Activity. Antimicrob Agents Chemother 2021; 65:AAC.01278-20. [PMID: 33468470 DOI: 10.1128/aac.01278-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 01/05/2021] [Indexed: 02/02/2023] Open
Abstract
Toxoplasma gondii and Cryptosporidium parvum, members of the phylum Apicomplexa, are significant pathogens of both humans and animals worldwide for which new and effective therapeutics are needed. Here, we describe the activity of the antibiotic boromycin against Toxoplasma and Cryptosporidium Boromycin potently inhibited intracellular proliferation of both T. gondii and C. parvum at half-maximal effective concentrations (EC50) of 2.27 nM and 4.99 nM, respectively. Treatment of extracellular T. gondii tachyzoites with 25 nM boromycin for 30 min suppressed 84% of parasite growth, but T. gondii tachyzoite invasion into host cells was not affected by boromycin. Immunofluorescence of boromycin-treated T. gondii showed loss of morphologically intact parasites with randomly distributed surface antigens inside the parasitophorous vacuoles. Boromycin exhibited a high selectivity for the parasites over their host cells. These results suggest that boromycin is a promising new drug candidate for treating toxoplasmosis and cryptosporidiosis.
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Copaifera spp. oleoresins impair Toxoplasma gondii infection in both human trophoblastic cells and human placental explants. Sci Rep 2020; 10:15158. [PMID: 32938966 PMCID: PMC7495442 DOI: 10.1038/s41598-020-72230-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 08/27/2020] [Indexed: 12/11/2022] Open
Abstract
The combination of pyrimethamine and sulfadiazine is the standard care in cases of congenital toxoplasmosis. However, therapy with these drugs is associated with severe and sometimes life-threatening side effects. The investigation of phytotherapeutic alternatives to treat parasitic diseases without acute toxicity is essential for the advancement of current therapeutic practices. The present study investigates the antiparasitic effects of oleoresins from different species of Copaifera genus against T. gondii. Oleoresins from C. reticulata, C. duckei, C. paupera, and C. pubiflora were used to treat human trophoblastic cells (BeWo cells) and human villous explants infected with T. gondii. Our results demonstrated that oleoresins were able to reduce T. gondii intracellular proliferation, adhesion, and invasion. We observed an irreversible concentration-dependent antiparasitic action in infected BeWo cells, as well as parasite cell cycle arrest in the S/M phase. The oleoresins altered the host cell environment by modulation of ROS, IL-6, and MIF production in BeWo cells. Also, Copaifera oleoresins reduced parasite replication and TNF-α release in villous explants. Anti-T. gondii effects triggered by the oleoresins are associated with immunomodulation of the host cells, as well as, direct action on parasites.
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Bowden GD, Reis PM, Rogers MB, Bone Relat RM, Brayton KA, Wilson SK, Di Genova BM, Knoll LJ, Nepveux V FJ, Tai AK, Ramadhar TR, Clardy J, O'Connor RM. A conserved coccidian gene is involved in Toxoplasma sensitivity to the anti-apicomplexan compound, tartrolon E. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2020; 14:1-7. [PMID: 32738587 PMCID: PMC7394737 DOI: 10.1016/j.ijpddr.2020.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/20/2020] [Accepted: 07/23/2020] [Indexed: 12/23/2022]
Abstract
New treatments for the diseases caused by apicomplexans are needed. Recently, we determined that tartrolon E (trtE), a secondary metabolite derived from a shipworm symbiotic bacterium, has broad-spectrum anti-apicomplexan parasite activity. TrtE inhibits apicomplexans at nM concentrations in vitro, including Cryptosporidium parvum, Toxoplasma gondii, Sarcocystis neurona, Plasmodium falciparum, Babesia spp. and Theileria equi. To investigate the mechanism of action of trtE against apicomplexan parasites, we examined changes in the transcriptome of trtE-treated T. gondii parasites. RNA-Seq data revealed that the gene, TGGT1_272370, which is broadly conserved in the coccidia, is significantly upregulated within 4 h of treatment. Using bioinformatics and proteome data available on ToxoDB, we determined that the protein product of this tartrolon E responsive gene (trg) has multiple transmembrane domains, a phosphorylation site, and localizes to the plasma membrane. Deletion of trg in a luciferase-expressing T. gondii strain by CRISPR/Cas9 resulted in a 68% increase in parasite resistance to trtE treatment, supporting a role for the trg protein product in the response of T. gondii to trtE treatment. Trg is conserved in the coccidia, but not in more distantly related apicomplexans, indicating that this response to trtE may be unique to the coccidians, and other mechanisms may be operating in other trtE-sensitive apicomplexans. Uncovering the mechanisms by which trtE inhibits apicomplexans may identify shared pathways critical to apicomplexan parasite survival and advance the search for new treatments.
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Affiliation(s)
- Gregory D Bowden
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, P.O. Box 647040, Pullman, WA, 99164-7040, USA
| | - Patricia M Reis
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, P.O. Box 647040, Pullman, WA, 99164-7040, USA
| | - Maxwell B Rogers
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, P.O. Box 647040, Pullman, WA, 99164-7040, USA
| | - Rachel M Bone Relat
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, P.O. Box 647040, Pullman, WA, 99164-7040, USA
| | - Kelly A Brayton
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, P.O. Box 647040, Pullman, WA, 99164-7040, USA
| | - Sarah K Wilson
- Department of Medical Microbiology and Immunology, University of Wisconsin - Madison, 1550 Linden Dr Madison, WI, 53706, USA
| | - Bruno Martorelli Di Genova
- Department of Medical Microbiology and Immunology, University of Wisconsin - Madison, 1550 Linden Dr Madison, WI, 53706, USA
| | - Laura J Knoll
- Department of Medical Microbiology and Immunology, University of Wisconsin - Madison, 1550 Linden Dr Madison, WI, 53706, USA
| | - Felix J Nepveux V
- Division of Geographic Medicine and Infectious Disease, Tufts Medical Center, 60 Tremont St 3rd Fl, Boston, MA, 02116, USA
| | - Albert K Tai
- Department of Immunology, Tufts University School of Medicine, 136 Harrison Ave, Boston, MA, 02111, USA
| | - Timothy R Ramadhar
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue C-213, Boston, MA, 02115, USA
| | - Jon Clardy
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue C-213, Boston, MA, 02115, USA
| | - Roberta M O'Connor
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, P.O. Box 647040, Pullman, WA, 99164-7040, USA.
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Harun MSR, Taylor M, Zhu XQ, Elsheikha HM. Transcriptome Profiling of Toxoplasma gondii-Infected Human Cerebromicrovascular Endothelial Cell Response to Treatment with Monensin. Microorganisms 2020; 8:microorganisms8060842. [PMID: 32512820 PMCID: PMC7356316 DOI: 10.3390/microorganisms8060842] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 05/26/2020] [Accepted: 06/01/2020] [Indexed: 01/21/2023] Open
Abstract
Central to the progression of cerebral toxoplasmosis is the interaction of Toxoplasma gondii with the blood-brain barrier (BBB) endothelial cells. In the present work, we tested the hypothesis that inhibition of Wnt pathway signalling by the monovalent ionophore monensin reduces the growth of T. gondii infecting human brain microvascular endothelial cells (hBMECs) or microglial cells. The anti-parasitic effect of monensin (a Wnt signalling inhibitor) on the in vitro growth of T. gondii tachyzoites was investigated using two methods (Sulforhodamine B staining and microscopic parasite counting). The monensin inhibited T. gondii growth (50% inhibitory concentration [IC50] = 0.61 μM) with a selective index = 8.48 when tested against hBMECs (50% cytotoxic concentration [CC50] = 5.17 μM). However, IC50 of monensin was 4.13 μM with a SI = 13.82 when tested against microglia cells (CC50 = 57.08 μM), suggesting less sensitivity of microglia cells to monensin treatment. The effect of T. gondii on the integrity of the BBB was assessed by the transendothelial electrical resistance (TEER) assay using an in vitro human BBB model. The results showed that T. gondii infection significantly decreased hBMECs' TEER resistance, which was rescued when cells were treated with 0.1 µM monensin, probably due to the anti-parasitic activity of monensin. We also investigated the host-targeted effects of 0.1 µM monensin on global gene expression in hBMECs with or without T. gondii infection. Treatment of hBMECs with monensin did not significantly influence the expression of genes involved in the Wnt signalling pathway, suggesting that although inhibition of the Wnt signalling pathway did not play a significant role in T. gondii infection of hBMECs, monensin was still effective in limiting the growth of T. gondii. On the contrary, monensin treatment downregulated pathways related to steroids, cholesterol and protein biosynthesis and their transport between endoplasmic reticulum and Golgi apparatus, and deregulated pathways related to cell cycle and DNA synthesis and repair mechanisms. These results provide new insight into the host-modulatory effect of monensin during T. gondii infection, which merits further investigation.
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Affiliation(s)
- Mohammad S. R. Harun
- Infectomics Cluster, Advanced Medical & Dental Institute, Universiti Sains Malaysia, Bertam, Kepala Batas, Pulau Pinang 13200, Malaysia;
| | - Mica Taylor
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK;
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
- Correspondence: (X.-Q.Z.); (H.M.E.); Tel.: +86-(0)931-834-2837 (X.-Q.Z.); +44-(0)115-951-6445 (H.M.E); Fax: +44-(0)115-951-6440 (H.M.E.)
| | - Hany M. Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK;
- Correspondence: (X.-Q.Z.); (H.M.E.); Tel.: +86-(0)931-834-2837 (X.-Q.Z.); +44-(0)115-951-6445 (H.M.E); Fax: +44-(0)115-951-6440 (H.M.E.)
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10
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O’Connor RM, Nepveux V FJ, Abenoja J, Bowden G, Reis P, Beaushaw J, Bone Relat RM, Driskell I, Gimenez F, Riggs MW, Schaefer DA, Schmidt EW, Lin Z, Distel DL, Clardy J, Ramadhar TR, Allred DR, Fritz HM, Rathod P, Chery L, White J. A symbiotic bacterium of shipworms produces a compound with broad spectrum anti-apicomplexan activity. PLoS Pathog 2020; 16:e1008600. [PMID: 32453775 PMCID: PMC7274485 DOI: 10.1371/journal.ppat.1008600] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 06/05/2020] [Accepted: 05/05/2020] [Indexed: 12/13/2022] Open
Abstract
Apicomplexan parasites cause severe disease in both humans and their domesticated animals. Since these parasites readily develop drug resistance, development of new, effective drugs to treat infection caused by these parasites is an ongoing challenge for the medical and veterinary communities. We hypothesized that invertebrate-bacterial symbioses might be a rich source of anti-apicomplexan compounds because invertebrates are susceptible to infections with gregarines, parasites that are ancestral to all apicomplexans. We chose to explore the therapeutic potential of shipworm symbiotic bacteria as they are bona fide symbionts, are easily grown in axenic culture and have genomes rich in secondary metabolite loci [1,2]. Two strains of the shipworm symbiotic bacterium, Teredinibacter turnerae, were screened for activity against Toxoplasma gondii and one strain, T7901, exhibited activity against intracellular stages of the parasite. Bioassay-guided fractionation identified tartrolon E (trtE) as the source of the activity. TrtE has an EC50 of 3 nM against T. gondii, acts directly on the parasite itself and kills the parasites after two hours of treatment. TrtE exhibits nanomolar to picomolar level activity against Cryptosporidium, Plasmodium, Babesia, Theileria, and Sarcocystis; parasites representing all branches of the apicomplexan phylogenetic tree. The compound also proved effective against Cryptosporidium parvum infection in neonatal mice, indicating that trtE may be a potential lead compound for preclinical development. Identification of a promising new compound after such limited screening strongly encourages further mining of invertebrate symbionts for new anti-parasitic therapeutics.
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Affiliation(s)
- Roberta M. O’Connor
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
- * E-mail:
| | - Felix J. Nepveux V
- Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Boston, Massachusetts, United States of America
| | - Jaypee Abenoja
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Gregory Bowden
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Patricia Reis
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Josiah Beaushaw
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Rachel M. Bone Relat
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Iwona Driskell
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Fernanda Gimenez
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America
| | - Michael W. Riggs
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, Arizona, United States of America
| | - Deborah A. Schaefer
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, Arizona, United States of America
| | - Eric W. Schmidt
- Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah, United States of America
| | - Zhenjian Lin
- Department of Medicinal Chemistry, University of Utah, Salt Lake City, Utah, United States of America
| | - Daniel L. Distel
- Ocean Genome Legacy Center, Northeastern University, Nahant, Massachusetts, United States of America
| | - Jon Clardy
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Cambridge, Massachusetts, United States of America
| | - Timothy R. Ramadhar
- Department of Chemistry, Howard University, Washington DC, United States of America
| | - David R. Allred
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, and Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America
| | - Heather M. Fritz
- California Animal Health and Food Safety Lab, University of California, Davis, California, United States of America
| | - Pradipsinh Rathod
- Department of Chemistry, University of Washington, Seattle, Washington, United States of America
| | - Laura Chery
- Department of Chemistry, University of Washington, Seattle, Washington, United States of America
| | - John White
- Department of Chemistry, University of Washington, Seattle, Washington, United States of America
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11
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Zhai B, He JJ, Elsheikha HM, Li JX, Zhu XQ, Yang X. Transcriptional changes in Toxoplasma gondii in response to treatment with monensin. Parasit Vectors 2020; 13:84. [PMID: 32070423 PMCID: PMC7029487 DOI: 10.1186/s13071-020-3970-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Accepted: 02/13/2020] [Indexed: 01/05/2023] Open
Abstract
Background Infection with the apicomplexan protozoan parasite T. gondii can cause severe and potentially fatal cerebral and ocular disease, especially in immunocompromised individuals. The anticoccidial ionophore drug monensin has been shown to have anti-Toxoplasma gondii properties. However, the comprehensive molecular mechanisms that underlie the effect of monensin on T. gondii are still largely unknown. We hypothesized that analysis of T. gondii transcriptional changes induced by monensin treatment can reveal new aspects of the mechanism of action of monensin against T. gondii. Methods Porcine kidney (PK)-15 cells were infected with tachyzoites of T. gondii RH strain. Three hours post-infection, PK-15 cells were treated with 0.1 μM monensin, while control cells were treated with medium only. PK-15 cells containing intracellular tachyzoites were harvested at 6 and 24 h post-treatment, and the transcriptomic profiles of T. gondii-infected PK-15 cells were examined using high-throughput RNA sequencing (RNA-seq). Quantitative real-time PCR was used to verify the expression of 15 differentially expressed genes (DEGs) identified by RNA-seq analysis. Results A total of 4868 downregulated genes and three upregulated genes were identified in monensin-treated T. gondii, indicating that most of T. gondii genes were suppressed by monensin. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of T. gondii DEGs showed that T. gondii metabolic and cellular pathways were significantly downregulated. Spliceosome, ribosome, and protein processing in endoplasmic reticulum were the top three most significantly enriched pathways out of the 30 highly enriched pathways detected in T. gondii. This result suggests that monensin, via down-regulation of protein biosynthesis in T. gondii, can limit the parasite growth and proliferation. Conclusions Our findings provide a comprehensive insight into T. gondii genes and pathways with altered expression following monensin treatment. These data can be further explored to achieve better understanding of the specific mechanism of action of monensin against T. gondii.![]()
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Affiliation(s)
- Bintao Zhai
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, Inner Mongolia Autonomous Region, People's Republic of China.,State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, Gansu, People's Republic of China
| | - Jun-Jun He
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, Gansu, People's Republic of China
| | - Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK
| | - Jie-Xi Li
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, Gansu, People's Republic of China
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, Gansu, People's Republic of China. .,Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University College of Veterinary Medicine, Yangzhou, 225009, Jiangsu, People's Republic of China.
| | - Xiaoye Yang
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, Inner Mongolia Autonomous Region, People's Republic of China.
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12
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Antoszczak M, Steverding D, Huczyński A. Anti-parasitic activity of polyether ionophores. Eur J Med Chem 2019; 166:32-47. [DOI: 10.1016/j.ejmech.2019.01.035] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 01/08/2019] [Accepted: 01/15/2019] [Indexed: 02/04/2023]
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13
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Sánchez-Sánchez R, Vázquez P, Ferre I, Ortega-Mora LM. Treatment of Toxoplasmosis and Neosporosis in Farm Ruminants: State of Knowledge and Future Trends. Curr Top Med Chem 2019; 18:1304-1323. [PMID: 30277158 PMCID: PMC6340160 DOI: 10.2174/1568026618666181002113617] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/03/2018] [Accepted: 09/13/2018] [Indexed: 12/17/2022]
Abstract
Toxoplasmosis and neosporosis are closely related protozoan diseases that lead to important economic impacts in farm ruminants. Toxoplasma gondii infection mainly causes reproductive failure in small ruminants and is a widespread zoonosis, whereas Neospora caninum infection is one of the most important causes of abortion in cattle worldwide. Vaccination has been considered the most economic measure for controlling these diseases. However, despite vaccine development efforts, only a live-attenuated T. gondii vaccine has been licensed for veterinary use, and no promising vaccines against ne-osporosis have been developed; therefore, vaccine development remains a key goal. Additionally, drug therapy could be a valuable strategy for disease control in farm ruminants, as several drugs that limit T. gondii and N. caninum proliferation and dissemination have been evaluated. This approach may also be relevant to performing an initial drug screening for potential human therapy for zoonotic parasites. Treat-ments can be applied against infections in adult ruminants to minimize the outcomes of a primo-infection or the reactivation of a chronic infection during gestation or in newborn ruminants to avoid infection chronification. In this review, the current status of drug development against toxoplasmosis and neosporo-sis in farm ruminants is presented, and in an effort to promote additional treatment options, prospective drugs that have shown efficacy in vitro and in laboratory animal models of toxoplasmosis and neosporosis are examined
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Affiliation(s)
- Roberto Sánchez-Sánchez
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Patricia Vázquez
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Ignacio Ferre
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Luis Miguel Ortega-Mora
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
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14
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Human Placental Syncytiotrophoblasts Restrict Toxoplasma gondii Attachment and Replication and Respond to Infection by Producing Immunomodulatory Chemokines. mBio 2018; 9:mBio.01678-17. [PMID: 29317509 PMCID: PMC5760739 DOI: 10.1128/mbio.01678-17] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Toxoplasma gondii is a major source of congenital disease worldwide, but the cellular and molecular factors associated with its vertical transmission are largely unknown. In humans, the placenta forms the key interface between the maternal and fetal compartments and forms the primary barrier that restricts the hematogenous spread of microorganisms. Here, we utilized primary human trophoblast (PHT) cells isolated from full-term placentas and human midgestation chorionic villous explants to determine the mechanisms by which human trophoblasts restrict and respond to T. gondii infection. We show that placental syncytiotrophoblasts, multinucleated cells that are in direct contact with maternal blood, restrict T. gondii infection at two distinct stages of the parasite lytic cycle—at the time of attachment and also during intracellular replication. Utilizing comparative transcriptome sequencing (RNA-seq) transcriptional profiling, we also show that human placental trophoblasts from both the second and third trimesters respond uniquely to T. gondii infection compared to trophoblast cell lines, typified by the upregulation of several immunity-related genes. One of the most differentially induced genes was the chemokine CCL22, which relies on the secretion of a parasite effector(s) either during or after invasion for its induction. Collectively, our findings provide new insights into the mechanisms by which the human placenta restricts the vertical transmission of T. gondii at early and late stages of human pregnancy and demonstrate the existence of at least two interferon-independent pathways that restrict T. gondii access to the fetal compartment. Toxoplasma gondii is a major source of congenital disease worldwide and must breach the placental barrier to be transmitted from maternal blood to the developing fetus. The events associated with the vertical transmission of T. gondii are largely unknown. Here, we show that primary human syncytiotrophoblasts, the fetus-derived cells that comprise the primary placental barrier, restrict T. gondii infection at two distinct stages of the parasite life cycle and respond to infection by inducing a unique immunomodulatory transcriptional profile. Collectively, our findings provide important insights into the mechanisms by which human syncytiotrophoblasts restrict T. gondii infection at early and late stages of human pregnancy, identify both permissive and resistant human placental cell types, and identify the placenta-enriched signaling pathways induced in response to infection.
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15
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Lack of mitochondrial MutS homolog 1 in Toxoplasma gondii disrupts maintenance and fidelity of mitochondrial DNA and reveals metabolic plasticity. PLoS One 2017; 12:e0188040. [PMID: 29141004 PMCID: PMC5687708 DOI: 10.1371/journal.pone.0188040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 10/31/2017] [Indexed: 11/19/2022] Open
Abstract
The importance of maintaining the fidelity of the mitochondrial genome is underscored by the presence of various repair pathways within this organelle. Presumably, the repair of mitochondrial DNA would be of particular importance in organisms that possess only a single mitochondrion, like the human pathogens Plasmodium falciparum and Toxoplasma gondii. Understanding the machinery that maintains mitochondrial DNA in these parasites is of particular relevance, as mitochondrial function is a validated and effective target for anti-parasitic drugs. We previously determined that the Toxoplasma MutS homolog TgMSH1 localizes to the mitochondrion. MutS homologs are key components of the nuclear mismatch repair system in mammalian cells, and both yeast and plants possess MutS homologs that localize to the mitochondria where they regulate DNA stability. Here we show that the lack of TgMSH1 results in accumulation of single nucleotide variations in mitochondrial DNA and a reduction in mitochondrial DNA content. Additionally, parasites lacking TgMSH1 function can survive treatment with the cytochrome b inhibitor atovaquone. While the Tgmsh1 knockout strain has several missense mutations in cytochrome b, none affect amino acids known to be determinants of atovaquone sensitivity and atovaquone is still able to inhibit electron transport in the Tgmsh1 mutants. Furthermore, culture of Tgmsh1 mutant in the presence atovaquone leads to parasites with enhanced atovaquone resistance and complete shutdown of respiration. Thus, parasites lacking TgMSH1 overcome the disruption of mitochondrial DNA by adapting their physiology allowing them to forgo the need for oxidative phosphorylation. Consistent with this idea, the Tgmsh1 mutant is resistant to mitochondrial inhibitors with diverse targets and exhibits reduced ability to grow in the absence of glucose. This work shows TgMSH1 as critical for the maintenance and fidelity of the mitochondrial DNA in Toxoplasma, reveals a novel mechanism for atovaquone resistance, and exposes the physiological plasticity of this important human pathogen.
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16
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Resistance towards monensin is proposed to be acquired in a Toxoplasma gondii model by reduced invasion and egress activities, in addition to increased intracellular replication. Parasitology 2017; 145:313-325. [PMID: 28870270 DOI: 10.1017/s0031182017001512] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Monensin (Mon) is an anticoccidial polyether ionophore widely used to control coccidiosis. The extensive use of polyether ionophores on poultry farms resulted in widespread resistance, but the underlying resistance mechanisms are unknown in detail. For analysing the mode of action by which resistance against polyether ionophores is obtained, we induced in vitro Mon resistance in Toxoplasma gondii-RH strain (MonR-RH) and compared it with the sensitive parental strain (Sen-RH). The proteome assessment of MonR-RH and Sen-RH strains was obtained after isotopic labelling using stable isotope labelling by amino acid in cell culture. Relative proteomic quantification between resistant and sensitive strains was performed using liquid chromatography-mass spectrometry/mass spectrometry. Overall, 1024 proteins were quantified and 52 proteins of them were regulated. The bioinformatic analysis revealed regulation of cytoskeletal and transmembrane proteins being involved in transport mechanisms, metal ion-binding and invasion. During invasion, actin and microneme protein 8 (MIC8) are seem to be important for conoid extrusion and forming moving junction with host cells, respectively. Actin was significantly upregulated, while MIC8 was downregulated, which indicate an invasion reduction in the resistant strain. Resistance against Mon is not a simple process but it involves reduced invasion and egress activity of T. gondii tachyzoites while intracellular replication is enhanced.
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17
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Abstract
INTRODUCTION Despite the fact that diseases caused by protozoan parasites represent serious challenges for public health, animal production and welfare, only a limited panel of drugs has been marketed for clinical applications. AREAS COVERED Herein, the authors investigate two strategies, namely whole organism screening and target-based drug design. The present pharmacopoeia has resulted from whole organism screening, and the mode of action and targets of selected drugs are discussed. However, the more recent extensive genome sequencing efforts and the development of dry and wet lab genomics and proteomics that allow high-throughput screening of interactions between micromolecules and recombinant proteins has resulted in target-based drug design as the predominant focus in anti-parasitic drug development. Selected examples of target-based drug design studies are presented, and calcium-dependent protein kinases, important drug targets in apicomplexan parasites, are discussed in more detail. EXPERT OPINION Despite the enormous efforts in target-based drug development, this approach has not yet generated market-ready antiprotozoal drugs. However, whole-organism screening approaches, comprising of both in vitro and in vivo investigations, should not be disregarded. The repurposing of already approved and marketed drugs could be a suitable strategy to avoid fastidious approval procedures, especially in the case of neglected or veterinary parasitoses.
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Affiliation(s)
- Joachim Müller
- a Institute of Parasitology, Vetsuisse Faculty , University of Bern , Bern , Switzerland
| | - Andrew Hemphill
- a Institute of Parasitology, Vetsuisse Faculty , University of Bern , Bern , Switzerland
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18
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Charvat RA, Arrizabalaga G. Oxidative stress generated during monensin treatment contributes to altered Toxoplasma gondii mitochondrial function. Sci Rep 2016; 6:22997. [PMID: 26976749 PMCID: PMC4792157 DOI: 10.1038/srep22997] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 02/26/2016] [Indexed: 02/08/2023] Open
Abstract
The ionophore monensin displays potent activities against several coccidian parasites of veterinary and medical importance including the opportunistic pathogen of humans, Toxoplasma gondii. While monensin is used widely in animals, toxicity impedes its use in humans. Nonetheless, given its potency, understanding its mode of action would reveal vulnerable aspects of the parasite that can be exploited for drug development. We previously established that monensin induces Toxoplasma to undergo cell cycle arrest and an autophagy-like cell death. Interestingly, these effects are dependent on the mitochondrion-localized TgMSH-1 protein, suggesting that monensin disrupts mitochondrial function. We demonstrate that monensin treatment results in decreased mitochondrial membrane potential and altered morphology. These effects are mitigated by the antioxidant compound N-acetyl-cysteine suggesting that monensin causes an oxidative stress, which was indeed the case based on direct detection of reactive oxygen species. Moreover, over-expression of the antioxidant proteins glutaredoxin and peroxiredoxin 2 protect Toxoplasma from the deleterious effects of monensin. Thus, our studies show that the effects of monensin on Toxoplasma are due to a disruption of mitochondrial function caused by the induction of an oxidative stress and implicate parasite redox biology as a viable target for the development of drugs against Toxoplasma and related pathogenic parasites.
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Affiliation(s)
- Robert A Charvat
- Departments of Pharmacology and Toxicology Indiana University School of Medicine, Indianapolis, Indiana 46202, US
| | - Gustavo Arrizabalaga
- Departments of Pharmacology and Toxicology Indiana University School of Medicine, Indianapolis, Indiana 46202, US.,Departments of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana 46202, US
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19
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Salinomycin and other ionophores as a new class of antimalarial drugs with transmission-blocking activity. Antimicrob Agents Chemother 2015; 59:5135-44. [PMID: 26055362 DOI: 10.1128/aac.04332-14] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 05/21/2015] [Indexed: 11/20/2022] Open
Abstract
The drug target profile proposed by the Medicines for Malaria Venture for a malaria elimination/eradication policy focuses on molecules active on both asexual and sexual stages of Plasmodium, thus with both curative and transmission-blocking activities. The aim of the present work was to investigate whether the class of monovalent ionophores, which includes drugs used in veterinary medicine and that were recently proposed as human anticancer agents, meets these requirements. The activity of salinomycin, monensin, and nigericin on Plasmodium falciparum asexual and sexual erythrocytic stages and on the development of the Plasmodium berghei and P. falciparum mosquito stages is reported here. Gametocytogenesis of the P. falciparum strain 3D7 was induced in vitro, and gametocytes at stage II and III or stage IV and V of development were treated for different lengths of time with the ionophores and their viability measured with the parasite lactate dehydrogenase (pLDH) assay. The monovalent ionophores efficiently killed both asexual parasites and gametocytes with a nanomolar 50% inhibitory concentration (IC50). Salinomycin showed a fast speed of kill compared to that of standard drugs, and the potency was higher on stage IV and V than on stage II and III gametocytes. The ionophores inhibited ookinete development and subsequent oocyst formation in the mosquito midgut, confirming their transmission-blocking activity. Potential toxicity due to hemolysis was excluded, since only infected and not normal erythrocytes were damaged by ionophores. Our data strongly support the downstream exploration of monovalent ionophores for repositioning as new antimalarial and transmission-blocking leads.
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20
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Chen X, Gu Y, Singh K, Shang C, Barzegar M, Jiang S, Huang S. Maduramicin inhibits proliferation and induces apoptosis in myoblast cells. PLoS One 2014; 9:e115652. [PMID: 25531367 PMCID: PMC4274093 DOI: 10.1371/journal.pone.0115652] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Accepted: 11/26/2014] [Indexed: 11/19/2022] Open
Abstract
Maduramicin, a polyether ionophore antibiotic derived from the bacterium Actinomadura yumaensis, is currently used as a feed additive against coccidiosis in poultry worldwide. It has been clinically observed that maduramicin can cause skeletal muscle and heart cell damage, resulting in skeletal muscle degeneration, heart failure, and even death in animals and humans, if improperly used. However, the mechanism of its toxic action in myoblasts is not well understood. Using mouse myoblasts (C2C12) and human rhabdomyosarcoma (RD and Rh30) cells as an experimental model for myoblasts, here we found that maduramicin inhibited cell proliferation and induced cell death in a concentration-dependent manner. Further studies revealed that maduramicin induced accumulation of the cells at G0/G1 phase of the cell cycle, and induced apoptosis in the cells. Concurrently, maduramicin downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and CDC25A, and upregulated expression of the CDK inhibitors (p21Cip1 and p27Kip1), resulting in decreased phosphorylation of Rb. Maduramicin also induced expression of BAK, BAD, DR4, TRADD and TRAIL, leading to activation of caspases 8, 9 and 3 as well as cleavage of poly ADP ribose polymerase (PARP). Taken together, our results suggest that maduramicin executes its toxicity in myoblasts at least by inhibiting cell proliferation and inducing apoptotic cell death.
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Affiliation(s)
- Xin Chen
- Laboratory of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, P. R. China
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America
| | - Ying Gu
- Laboratory of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, P. R. China
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America
| | - Karnika Singh
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America
| | - Chaowei Shang
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America
- Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America
| | - Mansoureh Barzegar
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America
| | - Shanxiang Jiang
- Laboratory of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu Province, P. R. China
- * E-mail: (SJ); (SH)
| | - Shile Huang
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America
- Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America
- * E-mail: (SJ); (SH)
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21
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Lavine MD, Arrizabalaga G. Analysis of monensin sensitivity in Toxoplasma gondii reveals autophagy as a mechanism for drug induced death. PLoS One 2012; 7:e42107. [PMID: 22848721 PMCID: PMC3405052 DOI: 10.1371/journal.pone.0042107] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 07/02/2012] [Indexed: 11/18/2022] Open
Abstract
Understanding the mechanisms by which anti-parasitic drugs alter the physiology and ultimately kill is an important area of investigation. Development of novel parasitic drugs, as well as the continued utilization of existing drugs in the face of resistant parasite populations, requires such knowledge. Here we show that the anti-coccidial drug monensin kills Toxoplasma gondii by inducing autophagy in the parasites, a novel mechanism of cell death in response to an antimicrobial drug. Monensin treatment results autophagy, as shown by translocation of ATG8 to autophagosomes, as well as causing marked morphological changes in the parasites' mitochondria. Use of the autophagy inhibitor 3-methyladenine blocks autophagy and mitochondrial alterations, and enhances parasite survival, in monensin-exposed parasites, although it does not block other monensin-induced effects on the parasites, such as late S-phase cell cycle arrest. Monensin does not induce autophagy in a parasite strain deficient in the mitochondrial DNA repair enzyme TgMSH-1 an enzyme that mediates monensin-induced late S-phase arrest. TgMSH-1 therefore either mediates cell cycle arrest and autophagy independently, or autophagy occurs downstream of cell cycle arrest in a manner analogous to apoptosis of cells arrested in G2 of the cell cycle. Overall, our results point to autophagy as a potentially important mode of cell death of protozoan parasites in response to antimicrobial drugs and indicate that disruption of the autophagy pathway could result in drug resistance.
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Affiliation(s)
- Mark D. Lavine
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Gustavo Arrizabalaga
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- * E-mail:
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22
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Rausch V, Liu L, Apel A, Rettig T, Gladkich J, Labsch S, Kallifatidis G, Kaczorowski A, Groth A, Gross W, Gebhard MM, Schemmer P, Werner J, Salnikov AV, Zentgraf H, Büchler MW, Herr I. Autophagy mediates survival of pancreatic tumour-initiating cells in a hypoxic microenvironment. J Pathol 2012; 227:325-35. [PMID: 22262369 DOI: 10.1002/path.3994] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 01/07/2012] [Accepted: 01/12/2012] [Indexed: 02/07/2023]
Abstract
Involvement of dysregulated autophagy in cancer growth and progression has been shown in different tumour entities, including pancreatic ductal adenocarcinoma (PDA). PDA is an extremely aggressive tumour characterized by a small population of highly therapy-resistant cancer stem cells (CSCs) capable of self-renewal and migration. We examined whether autophagy might be involved in the survival of CSCs despite nutrition and oxygen deprivation typical for the hypoxic tumour microenvironment of PDA. Immunohistochemistry revealed that markers for hypoxia, CSCs and autophagy are co-expressed in patient-derived tissue of PDA. Hypoxia starvation (H/S) enhanced clonogenic survival and migration of established pancreatic cancer cells with stem-like properties (CSC(high)), while pancreatic tumour cells with fewer stem cell markers (CSC(low)) did not survive these conditions. Electron microscopy revealed more advanced autophagic vesicles in CSC(high) cells, which exhibited higher expression of autophagy-related genes under normoxic conditions and relative to CSC(low) cells, as found by RT-PCR and western blot analysis. LC3 was already fully converted to the active LC3-II form in both cell lines, as evaluated by western blot and detection of accumulated GFP-LC3 protein by fluorescence microscopy. H/S increased formation of autophagic and acid vesicles, as well as expression of autophagy-related genes, to a higher extent in CSC(high) cells. Modulation of autophagy by inhibitors and activators resensitized CSC(high) to apoptosis and diminished clonogenicity, spheroid formation, expression of CSC-related genes, migratory activity and tumourigenicity in mice. Our data suggest that enhanced autophagy levels may enable survival of CSC(high) cells under H/S. Interference with autophagy-activating or -inhibiting drugs disturbs the fine-tuned physiological balance of enhanced autophagy in CSC and switches survival signalling to suicide.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Autophagy/drug effects
- Autophagy/genetics
- Biomarkers, Tumor/metabolism
- Blotting, Western
- Carcinoma, Pancreatic Ductal/drug therapy
- Carcinoma, Pancreatic Ductal/genetics
- Carcinoma, Pancreatic Ductal/metabolism
- Carcinoma, Pancreatic Ductal/pathology
- Carcinoma, Pancreatic Ductal/ultrastructure
- Cell Hypoxia
- Cell Line, Tumor
- Cell Movement
- Cell Survival
- Female
- Gene Expression Regulation, Neoplastic
- Humans
- Immunohistochemistry
- Mice
- Mice, Nude
- Microscopy, Electron
- Microscopy, Fluorescence
- Neoplastic Stem Cells/drug effects
- Neoplastic Stem Cells/metabolism
- Neoplastic Stem Cells/pathology
- Neoplastic Stem Cells/ultrastructure
- Pancreatic Neoplasms/drug therapy
- Pancreatic Neoplasms/genetics
- Pancreatic Neoplasms/metabolism
- Pancreatic Neoplasms/pathology
- Pancreatic Neoplasms/ultrastructure
- Polymerase Chain Reaction
- Time Factors
- Tumor Burden
- Tumor Microenvironment
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Affiliation(s)
- Vanessa Rausch
- Molecular OncoSurgery, University of Heidelberg and German Cancer Research Centre, Germany
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A novel benzodioxole-containing inhibitor of Toxoplasma gondii growth alters the parasite cell cycle. Antimicrob Agents Chemother 2011; 55:5438-51. [PMID: 21947387 DOI: 10.1128/aac.00455-11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Toxoplasma gondii is an obligate intracellular parasite that can cause disease in the developing fetus and in immunocompromised humans. Infections can last for the life of the individual, and to date there are no drugs that eliminate the chronic cyst stages that are characteristic of this parasite. In an effort to identify new chemical scaffolds that could form the basis for new therapeutics, we carried out a chemoinformatic screen for compounds that had the potential to interact with members of a superfamily of parasite-secreted kinases and assayed them for growth inhibition in vitro. Of 17 candidate compounds, we identified one with potent antiparasitic activity. The compound has a 50% inhibitory concentration (IC(50)) of ~2 nM, and structure-function analyses implicate the benzodioxole moiety in its action. The compound does not appear to be cytotoxic to host cells. Using microarray analyses of both parasites and host cells treated with the compound, we found that the levels of very few host cell transcripts are altered by the compound, while a large number of parasite transcripts have a different abundance after compound treatment. Gene ontology analyses of parasite transcripts with a different abundance revealed an enrichment of cell cycle-related genes, suggesting that the compound alters progression of the parasite through the cell cycle. Assaying the nuclear content of treated parasites demonstrated that compound treatment significantly increased the percentage of parasites in the S/M phase of the cell cycle compared to controls. This compound and its analogs represent a novel scaffold with antiparasitic activity.
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