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Staroverov SA, Fomin AS, Kozlov SV, Volkov AA, Kozlov ES, Gabalov KP, Dykman LA. Immune Response of Mice Against Babesia canis Antigens is Enhanced When Antigen is Coupled to Gold Nanoparticles. Acta Parasitol 2021; 66:493-500. [PMID: 33165701 DOI: 10.1007/s11686-020-00305-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/22/2020] [Indexed: 10/22/2022]
Abstract
PURPOSE The aim of this study was to isolate Babesia canis soluble antigens and to investigate the effect of their conjugates with gold nanoparticles on the immunogenicity in laboratory animals. METHODS A procedure was developed for isolating and purifying B. canis antigens. The isolated culture antigen of B. canis 495 was coupled to gold nanoparticles, and the conjugate was used to immunize laboratory mice. RESULTS Western blotting showed that the resultant antiserum specifically recognized the proteins of the B. canis strains isolated from naturally infected dogs. The antibody titer, the respiratory activity of peritoneal macrophages, the proliferative activity of splenocytes, and the production of cytokines were maximal when the animals were immunized with the antigen-nanoparticle conjugate emulsified in complete Freund's adjuvant. Without adjuvant, the babesial antigen was weakly immunogenic. CONCLUSION Therefore, the use of gold nanoparticles as an antigen carrier induced a broad immune response involving both cellular and humoral responses. The antibodies raised by the proposed procedure are potentially effective at immunodetection of Babesia canis infections in dogs.
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Bringmann G, Fayez S, Shamburger W, Feineis D, Winiarczyk S, Janecki R, Adaszek Ł. Naphthylisoquinoline alkaloids and their synthetic analogs as potent novel inhibitors against Babesia canis in vitro. Vet Parasitol 2020; 283:109177. [PMID: 32629205 DOI: 10.1016/j.vetpar.2020.109177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 06/22/2020] [Accepted: 06/25/2020] [Indexed: 10/24/2022]
Abstract
Babesia canis is the predominant and clinically relevant canine Babesia species in Europe. Transmitted by vector ticks, the parasite enters red blood cells and induces a severe, potentially fatal hemolytic anemia. Here, we report on the antibabesial activities of three extracts of the West African tropical plant species Triphyophyllum peltatum (Dioncophyllaceae) and Ancistrocladus abbreviatus (Ancistrocladaceae) and of 13 genuine naphthylisoquinoline alkaloids isolated thereof. Two of the extracts and eight of the alkaloids were found to display strong activities against Babesia canis in vitro. Among the most potent compounds were the C,C-coupled dioncophyllines A (1a) and C (2) and the N,C-linked alkaloids ancistrocladium A (3) and B (4), with half-maximum inhibition concentration (IC50) values of 0.48 μM for 1a, 0.85 μM for 2, 1.90 μM for 3, and 1.23 μM for 4. Structure-activity relationship (SAR) studies on a small library of related genuine analogs and non-natural synthetic derivatives of 1a and 2 revealed the likewise naturally occurring alkaloid N-methyl-7-epi-dioncophylline A (6b) to be the most potent (IC50, 0.14 μM) among the investigated compounds. Although none of the tested naphthylisoquinolines showed 100 % inhibition of parasite infection - as displayed by imidocarb dipropionate (IC50, 0.07 μM), which was used as a positive control - the antibabesial potential of the dioncophyllines A (1a) and C (2) and related compounds such as 6b, its atropo-diastereomer 6a (IC50, 1.45 μM), and 8-O-(p-nitrobenzyl)dioncophylline A (14) (IC50, 0.82 μM) is to be considered as high. The SAR results showed that N-methylation and axial chirality exert a strong impact on the antibabasial activities of the naphthylisoquinolines presented here, whereas dimerization, as in jozimine A2 (5) (IC50, 140 μM), leads to a significant decrease of activity against B. canis. Alkaloids displaying good to high activities against B. canis like the dioncophyllines 1a, 2, 6a, and 6b were found to cause only a small degree of hemolysis (< 0.7 %), whereas compounds with moderate to weak antibabesial activities such as 6-O-methyl-4'-O-demethylancistrocladine (15a) (IC50, 14.0 μM) and its atropo-diastereomer 6-O-methyl-4'-O-demethylhamatine (15b) (IC50, 830 μM) caused a high degree of hemolysis (7.3 % for 15a and 11.2 % for 15b). In this respect, the most effective anti-Babesia naphthylisoquinolines are also the safest ones.
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Affiliation(s)
- Gerhard Bringmann
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, D-97074, Würzburg, Germany.
| | - Shaimaa Fayez
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, D-97074, Würzburg, Germany; Department of Pharmacognosy, Faculty of Pharmacy, Ain-Shams University, Organization of African Unity Street 1, 11566, Cairo, Egypt
| | - William Shamburger
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, D-97074, Würzburg, Germany
| | - Doris Feineis
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, D-97074, Würzburg, Germany
| | - Stanislaw Winiarczyk
- Department of Epizootiology and Clinic of Infectious Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, ul. Głęboka 30, 20-612, Lublin, Poland
| | - Radoslaw Janecki
- Department of Epizootiology and Clinic of Infectious Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, ul. Głęboka 30, 20-612, Lublin, Poland
| | - Łukasz Adaszek
- Department of Epizootiology and Clinic of Infectious Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, ul. Głęboka 30, 20-612, Lublin, Poland.
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Gójska-Zygner O, Zygner W. Hyperaldosteronism and its association with hypotension and azotaemia in canine babesiosis. Vet Q 2014; 35:37-42. [PMID: 25347616 DOI: 10.1080/01652176.2014.981765] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
BACKGROUND The previous work on canine babesiosis revealed hypokalaemia and increased fractional excretion of potassium in infected dogs suggesting a role for aldosterone in the loss of potassium via the kidneys in affected dogs. Moreover, hypotension, which is one of the complications of canine babesiosis leading to renal failure, may induce secondary hyperaldosteronism. ANIMALS AND METHODS In this study, the serum aldosterone concentration was determined in 14 dogs infected with Babesia canis. The Mann-Whitney U test was used to compare serum aldosterone concentration and blood pressure between these dogs and 10 healthy dogs. Spearman's rank correlations between serum aldosterone concentration and blood pressure and between serum aldosterone and urea and creatinine concentrations were calculated. RESULTS Increased concentrations of aldosterone above reference intervals were observed in only 4 out of the 14 dogs. The results showed significantly (p < 0.05) higher serum aldosterone concentrations and lower blood pressures in infected dogs in comparison to healthy dogs, and significantly negative correlations between aldosterone concentration and systolic arterial pressure (r = -0.63), diastolic arterial pressure (r = -0.67) and mean arterial pressure (r = -0.65). Serum aldosterone concentration was also significantly correlated with serum urea concentration (r = 0.72), serum creatinine concentration (r = 0.69) and serum potassium concentration (r = -0.57). CONCLUSION The results of this study show hyperaldosteronism in some cases of canine babesiosis as a possible response to hypotension. However, both the hypotension and severe azotaemia observed in dogs infected with B. canis and associated hyperaldosteronaemia suggest that this response is insufficient.
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Increased concentration of serum TNF alpha and its correlations with arterial blood pressure and indices of renal damage in dogs infected with Babesia canis. Parasitol Res 2014; 113:1499-503. [PMID: 24553975 PMCID: PMC3951886 DOI: 10.1007/s00436-014-3792-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 01/28/2014] [Indexed: 11/03/2022]
Abstract
Canine babesiosis is a tick-borne disease caused by parasites of the genus Babesia. Tumour necrosis factor alpha (TNF-α) is a cytokine that plays a role in the pathogenesis of canine babesiosis. In this study, the authors determined the concentration of serum TNF-α in 11 dogs infected with Babesia canis and calculated Spearman’s rank correlations between the concentration of TNF-α and blood pressure, and between TNF-α and indices of renal damage such as: fractional excretion of sodium (FE(Na+)), urinary creatinine to serum creatinine ratio (UCr/SCr), renal failure index (RFI), urine specific gravity (USG) and urinary protein to urinary creatinine ratio (UPC). The results demonstrated statistically significant strong negative correlations between TNF-α and systolic arterial pressure (r = −0.7246), diastolic arterial pressure (r = −0.6642) and mean arterial pressure (r = −0.7151). Serum TNF-α concentration was also statistically significantly correlated with FE(Na+) (r = 0.7056), UCr/SCr (r = −0.8199), USG (r = −0.8075) and duration of the disease (r = 0.6767). The results of this study show there is an increase of serum TNF-α concentration during canine babesiosis, and the increased TNF-α concentration has an influence on the development of hypotension and renal failure in canine babesiosis. This probably results from the fact that TNF-α is involved in the production of nitric oxide and induction of vasodilation and hypotension, which may cause renal ischaemia and hypoxia, and finally acute tubular necrosis and renal failure.
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