1
|
Hampton N, Smith V, Brewer MT, Jesudoss Chelladurai JRJ. Strain-level variations of Dirofilaria immitis microfilariae in two biochemical assays. PLoS One 2024; 19:e0307261. [PMID: 39018313 PMCID: PMC11253964 DOI: 10.1371/journal.pone.0307261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 07/02/2024] [Indexed: 07/19/2024] Open
Abstract
BACKGROUND The increase in reports of resistance to macrocyclic lactones in the canine heartworm, Dirofilaria immitis is alarming. While DNA based tests have been well-validated, they can be expensive. In a previous study, we showed that two biochemical tests adapted to a 96- well plate format and read in a spectrophotometer could detect differences among lab validated D. immitis isolates. The two tests- Resazurin reduction and Hoechst 33342 efflux-detect metabolism and P-glycoprotein activity respectively in microfilariae isolated from infected dog blood. METHODS Our objective was to optimize the two assays further by testing various assay parameters in D. immitis isolates not tested previously. We tested microfilarial seeding density, incubation time and the effect of in vitro treatment with ivermectin and doxycycline in five other D. immitis isolates-JYD-34, Big Head, Berkeley, Georgia III and LOL. All assays were performed in 3 technical replicates and 2-4 biological replicates. To understand the molecular basis of the assays, we also performed qPCR for selected drug metabolism and elimination associated genes of the ABC transporter and cytochrome P450 gene families. RESULTS Metabolism and ABC transporter activity as detected by these assays varied between strains. Anthelmintic status (resistant or susceptible) did not correlate with metabolism or P-gp efflux. Basal transcriptional variations were found between strains in ABC transporter and cytochrome P450 genes. CONCLUSIONS These assays provide a greater understanding of the biochemical variation among isolates of D. immitis, which can be exploited in the future to develop in vitro diagnostic tests capable of differentiating susceptible and resistant isolates.
Collapse
Affiliation(s)
- Naomi Hampton
- Department of Diagnostic Medicine/Pathobiology, Kansas State University College of Veterinary Medicine, Manhattan, KS, United States of America
| | - Vicki Smith
- Department of Diagnostic Medicine/Pathobiology, Kansas State University College of Veterinary Medicine, Manhattan, KS, United States of America
| | - Matthew T. Brewer
- Department of Veterinary Pathology, Iowa State University College of Veterinary Medicine, Ames, Iowa, United States of America
| | - Jeba R. J. Jesudoss Chelladurai
- Department of Diagnostic Medicine/Pathobiology, Kansas State University College of Veterinary Medicine, Manhattan, KS, United States of America
| |
Collapse
|
2
|
Williams PDE, Brewer MT, Aroian RV, Robertson AP, Martin RJ. The nematode (Ascaris suum) intestine is a location of synergistic anthelmintic effects of Cry5B and levamisole. PLoS Pathog 2024; 20:e1011835. [PMID: 38758969 PMCID: PMC11139322 DOI: 10.1371/journal.ppat.1011835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 05/30/2024] [Accepted: 04/26/2024] [Indexed: 05/19/2024] Open
Abstract
A novel group of biocidal compounds are the Crystal 3D (Cry) and Cytolytic (Cyt) proteins produced by Bacillus thuringiensis (Bt). Some Bt Cry proteins have a selective nematocidal activity, with Cry5B being the most studied. Cry5B kills nematode parasites by binding selectively to membrane glycosphingolipids, then forming pores in the cell membranes of the intestine leading to damage. Cry5B selectively targets multiple species of nematodes from different clades and has no effect against mammalian hosts. Levamisole is a cholinergic anthelmintic that acts by selectively opening L-subtype nicotinic acetylcholine receptor ion-channels (L-AChRs) that have been found on muscles of nematodes. A synergistic nematocidal interaction between levamisole and Cry5B at the whole-worm level has been described previously, but the location, mechanism and time-course of this synergism is not known. In this study we follow the timeline of the effects of levamisole and Cry5B on the Ca2+ levels in enterocyte cells in the intestine of Ascaris suum using fluorescence imaging. The peak Ca2+ responses to levamisole were observed after approximately 10 minutes while the peak responses to activated Cry5B were observed after approximately 80 minutes. When levamisole and Cry5B were applied simultaneously, we observed that the responses to Cry5B were bigger and occurred sooner than when it was applied by itself. It is proposed that the synergism is due to the cytoplasmic Ca2+ overload that is induced by the combination of levamisole opening Ca2+ permeable L-subtype nAChRs and the Ca2+ permeable Cry5B toxin pores produced in the enterocyte plasma membranes. The effect of levamisole potentiates and speeds the actions of Cry5B that gives rise to bigger Ca2+ overloads that accelerates cell-death of the enterocytes.
Collapse
Affiliation(s)
- Paul D. E. Williams
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Matthew T. Brewer
- Department of Veterinary Pathology, Iowa State University, Ames, Iowa, United States of America
| | - Raffi V. Aroian
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Alan P. Robertson
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Richard J. Martin
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| |
Collapse
|
3
|
Williams PDE, Brewer MT, Aroian R, Robertson AP, Martin RJ. The nematode ( Ascaris suum) intestine is a location of synergistic anthelmintic effects of Cry5B and levamisole. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.20.567786. [PMID: 38045368 PMCID: PMC10690214 DOI: 10.1101/2023.11.20.567786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
A novel group of biocidal compounds are the Crystal 3D (Cry) and Cytolytic (Cyt) proteins produced by Bacillus thuringiensis (Bt). Some Bt Cry proteins have a selective nematocidal activity, with Cry5B being the most studied. Cry5B kills nematode parasites by binding selectively to membrane glycosphingolipids, then forming pores in the cell membranes of the intestine leading to damage. Cry5B selectively targets multiple species of nematodes from different clades and has no effect against mammalian hosts. Levamisole is a cholinomimetic anthelmintic that acts by selectively opening L-subtype nicotinic acetylcholine receptor ion-channels (L-AChRs) that have been found on muscles of nematodes. A synergistic nematocidal interaction between levamisole and Cry5B has been described previously, but the location, mechanism and time-course of this synergism is not known. In this study we follow the timeline of the effects of levamisole and Cry5B on the Ca2+ levels in enterocyte cells from the intestine of Ascaris suum using fluorescence imaging. The peak Ca2+ responses to levamisole were observed after approximately 10 minutes while the peak responses to activated Cry5B were observed after approximately 80 minutes. When levamisole and Cry5B were applied simultaneously, we observed that the responses to Cry5B were bigger and occurred sooner than when it was applied by itself. It is proposed that there is an irreversible cytoplasmic Ca2+ overload that leads to necrotic cell-death in the enterocyte that is induced by levamisole opening Ca2+ permeable L-subtype nAChRs and the development of Ca2+ permeable Cry5B toxin pores in enterocyte plasma membranes. The effects of levamisole potentiate and speed the actions of Cry5B.
Collapse
Affiliation(s)
- Paul D. E. Williams
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Matthew T. Brewer
- Department of Veterinary Pathology, Iowa State University, Ames, Iowa, United States of America
| | - Raffi Aroian
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Alan P. Robertson
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Richard J. Martin
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| |
Collapse
|
4
|
Jesudoss Chelladurai JRJ, Martin KA, Vardaxis P, Reinemeyer C, Vijayapalani P, Robertson AP, Brewer MT. Repertoire of P-glycoprotein drug transporters in the zoonotic nematode Toxocara canis. Sci Rep 2023; 13:4971. [PMID: 36973306 PMCID: PMC10042841 DOI: 10.1038/s41598-023-31556-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 03/14/2023] [Indexed: 03/29/2023] Open
Abstract
Toxocara canis has a complex lifecycle including larval stages in the somatic tissue of dogs that tolerate macrocyclic lactones. In this study, we investigated T. canis permeability glycoproteins (P-gps, ABCB1) with a putative role in drug tolerance. Motility experiments demonstrated that while ivermectin failed to abrogate larval movement, the combination of ivermectin and the P-gp inhibitor verapamil induced larval paralysis. Whole organism assays revealed functional P-gp activity in larvae which were capable of effluxing the P-gp substrate Hoechst 33342 (H33342). Further investigation of H33342 efflux demonstrated a unique rank order of potency for known mammalian P-gp inhibitors, suggesting that one or more of the T. canis transporters has nematode-specific pharmacological properties. Analysis of the T. canis draft genome resulted in the identification of 13 annotated P-gp genes, enabling revision of predicted gene names and identification of putative paralogs. Quantitative PCR was used to measure P-gp mRNA expression in adult worms, hatched larvae, and somatic larvae. At least 10 of the predicted genes were expressed in adults and hatched larvae, and at least 8 were expressed in somatic larvae. However, treatment of larvae with macrocyclic lactones failed to significantly increase P-gp expression as measured by qPCR. Further studies are needed to understand the role of individual P-gps with possible contributions to macrocyclic lactone tolerance in T. canis.
Collapse
Affiliation(s)
- Jeba R J Jesudoss Chelladurai
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, IA, USA.
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Ave, Manhattan, KS, USA.
| | - Katy A Martin
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Pam Vardaxis
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | | | - Paramasivan Vijayapalani
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Alan P Robertson
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
| | - Matthew T Brewer
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, 1800 Christensen, Ames, IA, USA.
| |
Collapse
|
5
|
Williams PDE, Kashyap SS, McHugh MA, Brewer MT, Robertson AP, Martin RJ. Diethylcarbamazine, TRP channels and Ca 2+ signaling in cells of the Ascaris intestine. Sci Rep 2022; 12:21317. [PMID: 36494409 PMCID: PMC9734116 DOI: 10.1038/s41598-022-25648-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 12/02/2022] [Indexed: 12/13/2022] Open
Abstract
The nematode parasite intestine absorbs nutrients, is involved in innate immunity, can metabolize xenobiotics and as we show here, is also a site of action of the anthelmintic, diethylcarbamazine. Diethylcarbamazine (DEC) is used to treat lymphatic filariasis and activates TRP-2, GON-2 & CED-11 TRP channels in Brugia malayi muscle cells producing spastic paralysis. DEC also has stimulatory effects on ascarid nematode parasites. Using PCR techniques, we detected, in Ascaris suum intestine, message for: Asu-trp-2, Asu-gon-2, Asu-ced-11, Asu-ocr-1, Asu-osm-9 and Asu-trpa-1. Comparison of amino-acid sequences of the TRP channels of B. malayi, and A. suum revealed noteworthy similarity, suggesting that the intestine of Ascaris will also be sensitive to DEC. We used Fluo-3AM as a Ca2+ indicator and observed characteristic unsteady time-dependent increases in the Ca2+ signal in the intestine in response to DEC. Application of La3+ and the TRP channel inhibitors, 2-APB or SKF 96365, inhibited DEC mediated increases in intracellular Ca2+. These observations are important because they emphasize that the nematode intestine, in addition to muscle, is a site of action of DEC as well as other anthelmintics. DEC may also enhance the Ca2+ toxicity effects of other anthelmintics acting on the intestine or, increase the effects of other anthelmintics that are metabolized and excreted by the nematode intestine.
Collapse
Affiliation(s)
- Paul D E Williams
- Department of Biomedical Sciences, Iowa State University, Ames, IA, USA
| | | | - Mark A McHugh
- Department of Biomedical Sciences, Iowa State University, Ames, IA, USA
| | - Matthew T Brewer
- Department of Veterinary Pathology, Iowa State University, Ames, IA, USA
| | - Alan P Robertson
- Department of Biomedical Sciences, Iowa State University, Ames, IA, USA
| | - Richard J Martin
- Department of Biomedical Sciences, Iowa State University, Ames, IA, USA.
| |
Collapse
|
6
|
Mechanism of vitamin B6 benzoyl hydrazone platinum(II) complexes overcomes multidrug resistance in lung cancer. Eur J Med Chem 2022; 237:114415. [DOI: 10.1016/j.ejmech.2022.114415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/20/2022] [Accepted: 04/24/2022] [Indexed: 11/16/2022]
|