1
|
Matos ÂP, Saldanha-Corrêa FMP, Gomes RDS, Hurtado GR. Exploring microalgal and cyanobacterial metabolites with antiprotozoal activity against Leishmania and Trypanosoma parasites. Acta Trop 2024; 251:107116. [PMID: 38159713 DOI: 10.1016/j.actatropica.2023.107116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/27/2023] [Accepted: 12/27/2023] [Indexed: 01/03/2024]
Abstract
Neglected tropical diseases (NTD) like Leishmaniasis and trypanosomiasis affect millions of people annually, while currently used antiprotozoal drugs have serious side effects. Drug research based on natural products has shown that microalgae and cyanobacteria are a promising platform of biochemically active compounds with antiprotozoal activity. These unicellular photosynthetic organisms are rich in polyunsaturated fatty acids, pigments including phycocyanin, chlorophylls and carotenoids, polyphenols, bioactive peptides, terpenes, alkaloids, which have proven antioxidant, antimicrobial, antiviral, antiplasmodial and antiprotozoal properties. This review provides up-to-date information regarding ongoing studies on substances synthesized by microalgae and cyanobacteria with notable activity against Leishmania spp., Trypanosoma cruzi, and Trypanosoma brucei, the causative agents of Leishmaniasis, Chagas disease, and human African trypanosomiasis, respectively. Extracts of several freshwater or marine microalgae have been tested on different strains of Leishmania and Trypanosoma parasites. For instance, ethanolic extract of Chlamydomonas reinhardtii and Tetraselmis suecica have biological activity against T. cruzi, due to their high content of carotenoids, chlorophylls, phenolic compounds and flavonoids that are associated with trypanocidal activity. Halophilic Dunaliella salina showed moderate antileishmanial activity that may be attributed to the high β-carotene content in this microalga. Peptides such as almiramides, dragonamides, and herbamide that are biosynthesized by marine cyanobacteria Lyngbya majuscula were found to have increased activity in micromolar scale IC50 against L. donovani, T. Cruzi, and T. brucei parasites. The cyanobacterial peptides symplocamide and venturamide isolated from Symploca and Oscillatoria species, respectively, and the alkaloid nostocarbonile isolated from Nostoc have shown promising antiprotozoal properties and are being explored for pharmaceutical and medicinal purposes. The discovery of new molecules from microalgae and cyanobacteria with therapeutic potential against Leishmaniasis and trypanosomiasis may address an urgent medical need: effective and safe treatments of NTDs.
Collapse
Affiliation(s)
- Ângelo Paggi Matos
- Institute for Advanced Studies of Ocean, São Paulo State University (UNESP), Rodovia Presidente Dutra Km 138, Eugênio de Melo, São José dos Campos 12247-004, Brazil.
| | | | - Roberto da Silva Gomes
- Department of Pharmaceutical Sciences, North Dakota State University, Fargo, North Dakota 58105, United States
| | - Gabriela Ramos Hurtado
- Institute for Advanced Studies of Ocean, São Paulo State University (UNESP), Rodovia Presidente Dutra Km 138, Eugênio de Melo, São José dos Campos 12247-004, Brazil; Institute of Science and Technology, São Paulo State University (UNESP), Rodovia Presidente Dutra Km 138, Eugênio de Melo, São José dos Campos 12247-004, Brazil.
| |
Collapse
|
2
|
Periferakis AT, Periferakis A, Periferakis K, Caruntu A, Badarau IA, Savulescu-Fiedler I, Scheau C, Caruntu C. Antimicrobial Properties of Capsaicin: Available Data and Future Research Perspectives. Nutrients 2023; 15:4097. [PMID: 37836381 PMCID: PMC10574431 DOI: 10.3390/nu15194097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 09/13/2023] [Accepted: 09/20/2023] [Indexed: 10/15/2023] Open
Abstract
Capsaicin is a phytochemical derived from plants of the genus Capsicum and subject of intensive phytochemical research due to its numerous physiological and therapeutical effects, including its important antimicrobial properties. Depending on the concentration and the strain of the bacterium, capsaicin can exert either bacteriostatic or even bactericidal effects against a wide range of both Gram-positive and Gram-negative bacteria, while in certain cases it can reduce their pathogenicity by a variety of mechanisms such as mitigating the release of toxins or inhibiting biofilm formation. Likewise, capsaicin has been shown to be effective against fungal pathogens, particularly Candida spp., where it once again interferes with biofilm formation. The parasites Toxoplasma gondi and Trypanosoma cruzi have been found to be susceptible to the action of this compound too while there are also viruses whose invasiveness is significantly dampened by it. Among the most encouraging findings are the prospects for future development, especially using new formulations and drug delivery mechanisms. Finally, the influence of capsaicin in somatostatin and substance P secretion and action, offers an interesting array of possibilities given that these physiologically secreted compounds modulate inflammation and immune response to a significant extent.
Collapse
Affiliation(s)
- Aristodemos-Theodoros Periferakis
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Elkyda, Research & Education Centre of Charismatheia, 17675 Athens, Greece
| | - Argyrios Periferakis
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Elkyda, Research & Education Centre of Charismatheia, 17675 Athens, Greece
- Akadimia of Ancient Greek and Traditional Chinese Medicine, 16675 Athens, Greece
| | - Konstantinos Periferakis
- Akadimia of Ancient Greek and Traditional Chinese Medicine, 16675 Athens, Greece
- Pan-Hellenic Organization of Educational Programs (P.O.E.P), 17236 Athens, Greece
| | - Ana Caruntu
- Department of Oral and Maxillofacial Surgery, “Carol Davila” Central Military Emergency Hospital, 010825 Bucharest, Romania
- Department of Oral and Maxillofacial Surgery, Faculty of Dental Medicine, “Titu Maiorescu” University, 031593 Bucharest, Romania
| | - Ioana Anca Badarau
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Ilinca Savulescu-Fiedler
- Department of Internal Medicine and Cardiology, Coltea Clinical Hospital, 030167 Bucharest, Romania
- Department of Internal Medicine, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Cristian Scheau
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Radiology and Medical Imaging, “Foisor” Clinical Hospital of Orthopaedics, Traumatology and Osteoarticular TB, 021382 Bucharest, Romania
| | - Constantin Caruntu
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Dermatology, ‘Prof. N.C. Paulescu’ National Institute of Diabetes, Nutrition and Metabolic Diseases, 011233 Bucharest, Romania
| |
Collapse
|
3
|
Periferakis A, Periferakis K, Badarau IA, Petran EM, Popa DC, Caruntu A, Costache RS, Scheau C, Caruntu C, Costache DO. Kaempferol: Antimicrobial Properties, Sources, Clinical, and Traditional Applications. Int J Mol Sci 2022; 23:ijms232315054. [PMID: 36499380 PMCID: PMC9740324 DOI: 10.3390/ijms232315054] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/23/2022] [Accepted: 11/26/2022] [Indexed: 12/03/2022] Open
Abstract
Flavonoids are a category of plant-derived compounds which exhibit a large number of health-related effects. One of the most well-known and studied flavonoids is kaempferol, which can be found in a wide variety of herbs and plant families. Apart from their anticarcinogenic and anti-inflammatory effects, kaempferol and its associated compounds also exhibit antibacterial, antifungal, and antiprotozoal activities. The development of drugs and treatment schemes based on these compounds is becoming increasingly important in the face of emerging resistance of numerous pathogens as well as complex molecular interactions between various drug therapies. In addition, many of the kaempferol-containing plants are used in traditional systems all over the world for centuries to treat numerous conditions. Due to its variety of sources and associated compounds, some molecular mechanisms of kaempferol antimicrobial activity are well known while others are still under analysis. This paper thoroughly documents the vegetal and food sources of kaempferol as well as the most recent and significant studies regarding its antimicrobial applications.
Collapse
Affiliation(s)
- Argyrios Periferakis
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Akadimia of Ancient Greek and Traditional Chinese Medicine, 16675 Athens, Greece
| | - Konstantinos Periferakis
- Akadimia of Ancient Greek and Traditional Chinese Medicine, 16675 Athens, Greece
- Pan-Hellenic Organization of Educational Programs (P.O.E.P), 17236 Athens, Greece
- Orasis Acupuncture Institute, 11526 Athens, Greece
| | - Ioana Anca Badarau
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Elena Madalina Petran
- Department of Biochemistry, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Toxicology, Grigore Alexandrescu Emergency Children’s Hospital, 011743 Bucharest, Romania
| | - Delia Codruta Popa
- Department of Biochemistry, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Hematology, Fundeni Clinical Institute, 022328 Bucharest, Romania
- Correspondence: (D.C.P.); (C.S.)
| | - Ana Caruntu
- Department of Oral and Maxillofacial Surgery, ‘Dr. Carol Davila’ Central Military Emergency Hospital, 010825 Bucharest, Romania
- Department of Oral and Maxillofacial Surgery, Faculty of Dental Medicine, ‘Titu Maiorescu’ University, 031593 Bucharest, Romania
| | - Raluca Simona Costache
- Department of Gastroenterology, Gastroenterology and Internal Medicine Clinic, ‘Dr. Carol Davila’ Central Military Emergency Hospital, 010825 Bucharest, Romania
- Department of Internal Medicine and Gastroenterology, ‘Carol Davila’ University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Cristian Scheau
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Correspondence: (D.C.P.); (C.S.)
| | - Constantin Caruntu
- Department of Physiology, The “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Dermatology, ‘Prof. N.C. Paulescu’ National Institute of Diabetes, Nutrition and Metabolic Diseases, 011233 Bucharest, Romania
| | - Daniel Octavian Costache
- Department of Dermatology, ‘Dr. Carol Davila’ Central Military Emergency Hospital, 010825 Bucharest, Romania
| |
Collapse
|
4
|
Spectrofluorimetric determination of α-difluoromethylornithine through condensation with ninhydrin and phenylacetaldehyde: application to pharmaceutical cream and spiked urine samples. CHEMICAL PAPERS 2021. [DOI: 10.1007/s11696-021-01894-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
5
|
Abdel-Lateef MA, Almahri A. Micellar sensitized Resonance Rayleigh Scattering and spectrofluorometric methods based on isoindole formation for determination of Eflornithine in cream and biological samples. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 258:119806. [PMID: 33933938 DOI: 10.1016/j.saa.2021.119806] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/01/2021] [Accepted: 04/06/2021] [Indexed: 06/12/2023]
Abstract
α-Difluoromethylornithine or Eflornithine is an FDA-approved drug used for the treatment of Sleeping Sickness (as vials dosage form) and also used for diminishing the unwanted excess facial hair in the hirsutism (as creams dosage form). The proposed work is based on the condensation interaction between the amino moiety of Eflornithine and O-phthalaldehyde/2-mercaptoethanol to form a highly fluorescent isoindole derivative. The fluorescence and the Resonance Rayleigh Scattering (RRS) intensities of the reaction product were greatly augmented upon the addition of hexadecyl-trimethyl ammonium bromide by 153% and 250%, respectively. After optimization of the reaction conditions, the formed isoindole derivative was measured fluorometrically at λemission= 429 nm after λexcitation= 337 nm. Moreover, the significant augmentation in the RRS intensity of the formed product was measured at λmax= 422 nm. In regards to accuracy, sensitivity, robustness and precision, the proposed methods were validated according to ICH guidelines. Furthermore, the proposed methods were successfully applied for the assay of Eflornithine in various commercial brands of the pharmaceutical cream samples with good recovery. In addition to the current fluorometric method was confirmed to be effective in the assaying of Eflornithine in spiked plasma and urine specimens with good recovery.
Collapse
Affiliation(s)
- Mohamed A Abdel-Lateef
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Al-Azhar University, Assiut Branch, Assiut 71524, Egypt.
| | - Albandary Almahri
- General Courses Unit, Faculty of Sciences and Arts, King Khalid University, Dhahran Aljanoub, Saudi Arabia
| |
Collapse
|
6
|
Almahri A, Abdel-Lateef MA. Application of Hantzsch reaction for sensitive determination of eflornithine in cream, plasma and urine samples. ROYAL SOCIETY OPEN SCIENCE 2021; 8:210366. [PMID: 34040792 PMCID: PMC8113893 DOI: 10.1098/rsos.210366] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 04/14/2021] [Indexed: 05/05/2023]
Abstract
Eflornithine (EFN) is an anti-Trypanosoma brucei agent for the medication of sleeping sickness and widely distributed for the treatment of hirsutism (unwanted facial hair in women). The presented work demonstrates a comprehensive analytical approach for the spectrofluorometric determination of EFN in commercial cream samples and various biological samples. The proposed method is based on the formation of a highly yellow-green fluorescence dihydropyridine derivative after the interaction between EFN and acetylacetone/formaldehyde reagent in a slightly acidic medium. Furthermore, the optimal variables such as reagent volumes, pH of the medium, heating time, buffer volume, heating temperature and diluting solvent were carefully selected to achieve the maximum fluorescence activity. The fluorescence activity for the formed derivative was measured at λ emission = 477 nm after λ excitation = 418 nm. Concerning linearity, accuracy, sensitivity, precision and robustness, the presented method was validated and verified according to ICH guidelines. Moreover, the proposed work offered a selective determination for EFN in various brands of pharmaceutical cream without any interference from excipients. Eventually, the current approach was assured to be successful in the estimation of EFN in urine and plasma samples with acceptable recovery results.
Collapse
Affiliation(s)
- Albandary Almahri
- General Courses Unit, Faculty of Sciences and Arts, King Khalid University, Dhahran Aljanoub, Saudi Arabia
| | - Mohamed A. Abdel-Lateef
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Al-Azhar University, Assiut Branch, Assiut 71524, Egypt
| |
Collapse
|
7
|
Muraca G, Berti IR, Sbaraglini ML, Fávaro WJ, Durán N, Castro GR, Talevi A. Trypanosomatid-Caused Conditions: State of the Art of Therapeutics and Potential Applications of Lipid-Based Nanocarriers. Front Chem 2020; 8:601151. [PMID: 33324615 PMCID: PMC7726426 DOI: 10.3389/fchem.2020.601151] [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: 08/31/2020] [Accepted: 10/19/2020] [Indexed: 11/13/2022] Open
Abstract
Trypanosomatid-caused conditions (African trypanosomiasis, Chagas disease, and leishmaniasis) are neglected tropical infectious diseases that mainly affect socioeconomically vulnerable populations. The available therapeutics display substantial limitations, among them limited efficacy, safety issues, drug resistance, and, in some cases, inconvenient routes of administration, which made the scenarios with insufficient health infrastructure settings inconvenient. Pharmaceutical nanocarriers may provide solutions to some of these obstacles, improving the efficacy-safety balance and tolerability to therapeutic interventions. Here, we overview the state of the art of therapeutics for trypanosomatid-caused diseases (including approved drugs and drugs undergoing clinical trials) and the literature on nanolipid pharmaceutical carriers encapsulating approved and non-approved drugs for these diseases. Numerous studies have focused on the obtention and preclinical assessment of lipid nanocarriers, particularly those addressing the two currently most challenging trypanosomatid-caused diseases, Chagas disease, and leishmaniasis. In general, in vitro and in vivo studies suggest that delivering the drugs using such type of nanocarriers could improve the efficacy-safety balance, diminishing cytotoxicity and organ toxicity, especially in leishmaniasis. This constitutes a very relevant outcome, as it opens the possibility to extended treatment regimens and improved compliance. Despite these advances, last-generation nanosystems, such as targeted nanocarriers and hybrid systems, have still not been extensively explored in the field of trypanosomatid-caused conditions and represent promising opportunities for future developments. The potential use of nanotechnology in extended, well-tolerated drug regimens is particularly interesting in the light of recent descriptions of quiescent/dormant stages of Leishmania and Trypanosoma cruzi, which have been linked to therapeutic failure.
Collapse
Affiliation(s)
- Giuliana Muraca
- Laboratory of Bioactive Research and Development (LIDeB), Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata (UNLP), La Plata, Argentina
- Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT), Buenos Aires, Argentina
| | - Ignacio Rivero Berti
- Laboratorio de Nanobiomateriales, Centro de Investigación y Desarrollo en Fermentaciones Industriales (CINDEFI), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP) -CONICET (CCT La Plata), La Plata, Argentina
| | - María L. Sbaraglini
- Laboratory of Bioactive Research and Development (LIDeB), Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata (UNLP), La Plata, Argentina
| | - Wagner J. Fávaro
- Laboratory of Urogenital Carcinogenesis and Immunotherapy, Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Nelson Durán
- Laboratory of Urogenital Carcinogenesis and Immunotherapy, Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
- Nanomedicine Research Unit (Nanomed), Federal University of ABC (UFABC), Santo André, Brazil
| | - Guillermo R. Castro
- Laboratorio de Nanobiomateriales, Centro de Investigación y Desarrollo en Fermentaciones Industriales (CINDEFI), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP) -CONICET (CCT La Plata), La Plata, Argentina
| | - Alan Talevi
- Laboratory of Bioactive Research and Development (LIDeB), Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata (UNLP), La Plata, Argentina
| |
Collapse
|
8
|
Zhao Z, Dai X, Li C, Wang X, Tian J, Feng Y, Xie J, Ma C, Nie Z, Fan P, Qian M, He X, Wu S, Zhang Y, Zheng X. Pyrazolone structural motif in medicinal chemistry: Retrospect and prospect. Eur J Med Chem 2019; 186:111893. [PMID: 31761383 PMCID: PMC7115706 DOI: 10.1016/j.ejmech.2019.111893] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 11/14/2019] [Accepted: 11/14/2019] [Indexed: 12/13/2022]
Abstract
The pyrazolone structural motif is a critical element of drugs aimed at different biological end-points. Medicinal chemistry researches have synthesized drug-like pyrazolone candidates with several medicinal features including antimicrobial, antitumor, CNS (central nervous system) effect, anti-inflammatory activities and so on. Meanwhile, SAR (Structure-Activity Relationship) investigations have drawn attentions among medicinal chemists, along with a plenty of analogues have been derived for multiple targets. In this review, we comprehensively summarize the biological activity and SAR for pyrazolone analogues, wishing to give an overall retrospect and prospect on the pyrazolone derivatives. The pyrazolone structural motif is a critical element of drugs aimed at different biological end-points. The pyrazolone analogues have been carried out to drug-like candidates with broad range of medicinal properties. This review wishes to give an overall retrospect and prospect on the pyrazolone derivatives.
Collapse
Affiliation(s)
- Zefeng Zhao
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Xufen Dai
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Chenyang Li
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Xiao Wang
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Jiale Tian
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Ying Feng
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Jing Xie
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Cong Ma
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Zhuang Nie
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Peinan Fan
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| | - Mingcheng Qian
- Department of Medicinal Chemistry, School of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, 213164, Jiangsu, China; Laboratory for Medicinal Chemistry, Ghent University, Ottergemsesteenweg 460, B-9000, Ghent, Belgium
| | - Xirui He
- Department of Bioengineering, Zhuhai Campus of Zunyi Medical University, Zhuhai, 519041, China
| | - Shaoping Wu
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China.
| | - Yongmin Zhang
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China; Sorbonne Université, Institut Parisien de Chimie Moléculaire, CNRS UMR 8232, 4 Place Jussieu, 75005, Paris, France
| | - Xiaohui Zheng
- School of Pharmacy, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Biomedicine Key Laboratory of Shaanxi Province, Northwest University, 229 Taibai Road, Xi'an, 710069, China
| |
Collapse
|
9
|
Popov AB, Stolić I, Krstulović L, Taylor MC, Kelly JM, Tomić S, Tumir L, Bajić M, Raić-Malić S. Novel symmetric bis-benzimidazoles: Synthesis, DNA/RNA binding and antitrypanosomal activity. Eur J Med Chem 2019; 173:63-75. [PMID: 30986572 DOI: 10.1016/j.ejmech.2019.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/22/2019] [Accepted: 04/02/2019] [Indexed: 12/11/2022]
Abstract
The novel benzimidazol-2-yl-fur-5-yl-(1,2,3)-triazolyl dimeric series with aliphatic and aromatic central linkers was successfully prepared with the aim of assessing binding affinity to DNA/RNA and antitrypanosomal activity. UV-Visible spectroscopy, thermal denaturation showed interaction of heterocyclic bis-amidines with ctDNA. Circular dichroism studies indicated uniform orientation of heterocyclic bis-amidines along the chiral double helix axis, revealing minor groove binding as the dominant binding mode. The amidino fragment and 1,4-bis(oxymethylene)phenyl spacer were the main determinants of activity against Trypanosoma brucei. The bis-benzimidazole imidazoline 15c, which had antitrypanosomal potency in the submicromolar range and DNA interacting properties, emerged as a candidate for further structural optimization to obtain more effective agents to combat trypanosome infections.
Collapse
Affiliation(s)
- A Bistrović Popov
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, HR-10000, Zagreb, Croatia
| | - I Stolić
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, HR-10000, Zagreb, Croatia
| | - L Krstulović
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, HR-10000, Zagreb, Croatia
| | - M C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - J M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - S Tomić
- Division of Organic Chemistry and Biochemistry, Physical Chemistry, Ruđer Bošković Institute, Bijenička 54, HR-10000, Zagreb, Croatia
| | - L Tumir
- Division of Organic Chemistry and Biochemistry, Laboratory for Biomolecular Interactions and Spectroscopy, Ruđer Bošković Institute, Bijenička 54, HR-10000, Zagreb, Croatia
| | - M Bajić
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, HR-10000, Zagreb, Croatia
| | - S Raić-Malić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, HR-10000, Zagreb, Croatia.
| |
Collapse
|
10
|
Luo H, Wood K, Shi FD, Gao F, Chang Y. Suramin is a novel competitive antagonist selective to α1β2γ2 GABA A over ρ1 GABA C receptors. Neuropharmacology 2018; 141:148-157. [PMID: 30172846 DOI: 10.1016/j.neuropharm.2018.08.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 08/12/2018] [Accepted: 08/26/2018] [Indexed: 02/05/2023]
Abstract
GABAA and GABAC receptors are both GABA-gated chloride channels with distinct pharmacological properties, mainly in their sensitivity to bicuculline and gabazine. In this study, we found that suramin, a purinergic receptor antagonist, is a novel competitive antagonist selective to GABAA over GABAC receptors. Specifically, suramin antagonized the GABA-induced current and the spontaneous opening current of the wild type α1β2γ2 GABAA receptor with high-level expression in Xenopus oocytes. The antagonism was concentration dependent with an IC50 that varied depending on the concentration of GABA, and with the lowest IC50 of 0.43 μM when antagonizing the spontaneous current. Thus, its potency is slightly higher than bicuculline on the same GABAA receptor. Suramin also antagonized the mouse native brain GABA receptors micro-transplanted into the Xenopus oocytes with its potency depending on the GABA concentration. In addition, in the presence of two fixed concentrations of suramin, the GABA concentration response of the receptor was shifted to the right without reduction of the maximum current. Thus, our results are consistent with that suramin is a competitive antagonist for the α1β2γ2 GABAA receptor. Interestingly, the rank order of maximum allosteric inhibition (efficacy) of spontaneous current of the GABAA receptor by three competitive antagonists was suramin > bicuculline > gabazine, similar to the rank order of their molecular weight. In contrast, similar to bicuculline, suramin has much lower potency in antagonizing the GABA-induced current of the ρ1 GABAC receptor. In conclusion, we have identified a novel GABAA receptor competitive antagonist, which is selective to the α1β2γ2 over ρ1 GABA receptors.
Collapse
Affiliation(s)
- Hui Luo
- Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong, China; Division of Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA
| | - Kristofer Wood
- Division of Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA
| | - Fu-Dong Shi
- Division of Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA
| | - Fenfei Gao
- Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong, China
| | - Yongchang Chang
- Division of Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA.
| |
Collapse
|
11
|
Kaufer A, Ellis J, Stark D, Barratt J. The evolution of trypanosomatid taxonomy. Parasit Vectors 2017; 10:287. [PMID: 28595622 PMCID: PMC5463341 DOI: 10.1186/s13071-017-2204-7] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 05/17/2017] [Indexed: 12/20/2022] Open
Abstract
Trypanosomatids are protozoan parasites of the class Kinetoplastida predominately restricted to invertebrate hosts (i.e. possess a monoxenous life-cycle). However, several genera are pathogenic to humans, animals and plants, and have an invertebrate vector that facilitates their transmission (i.e. possess a dixenous life-cycle). Phytomonas is one dixenous genus that includes several plant pathogens transmitted by phytophagous insects. Trypanosoma and Leishmania are dixenous genera that infect vertebrates, including humans, and are transmitted by hematophagous invertebrates. Traditionally, monoxenous trypanosomatids such as Leptomonas were distinguished from morphologically similar dixenous species based on their restriction to an invertebrate host. Nonetheless, this criterion is somewhat flawed as exemplified by Leptomonas seymouri which reportedly infects vertebrates opportunistically. Similarly, Novymonas and Zelonia are presumably monoxenous genera yet sit comfortably in the dixenous clade occupied by Leishmania. The isolation of Leishmania macropodum from a biting midge (Forcipomyia spp.) rather than a phlebotomine sand fly calls into question the exclusivity of the Leishmania-sand fly relationship, and its suitability for defining the Leishmania genus. It is now accepted that classic genus-defining characteristics based on parasite morphology and host range are insufficient to form the sole basis of trypanosomatid taxonomy as this has led to several instances of paraphyly. While improvements have been made, resolution of evolutionary relationships within the Trypanosomatidae is confounded by our incomplete knowledge of its true diversity. The known trypanosomatids probably represent a fraction of those that exist and isolation of new species will help resolve relationships in this group with greater accuracy. This review incites a dialogue on how our understanding of the relationships between certain trypanosomatids has shifted, and discusses new knowledge that informs the present taxonomy of these important parasites.
Collapse
Affiliation(s)
- Alexa Kaufer
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007 Australia
| | - John Ellis
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007 Australia
| | - Damien Stark
- Department of Microbiology, St Vincent’s Hospital Sydney, Darlinghurst, NSW 2010 Australia
| | - Joel Barratt
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007 Australia
| |
Collapse
|
12
|
Sun Y, Liu G, Cai Y. Thiolated arsenicals in arsenic metabolism: Occurrence, formation, and biological implications. J Environ Sci (China) 2016; 49:59-73. [PMID: 28007180 DOI: 10.1016/j.jes.2016.08.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 08/24/2016] [Accepted: 08/25/2016] [Indexed: 06/06/2023]
Abstract
Arsenic (As) is a notoriously toxic pollutant of health concern worldwide with potential risk of cancer induction, but meanwhile it is used as medicines for the treatment of different conditions including hematological cancers. Arsenic can undergo extensive metabolism in biological systems, and both toxicological and therapeutic effects of arsenic compounds are closely related to their metabolism. Recent studies have identified methylated thioarsenicals as a new class of arsenic metabolites in biological systems after exposure of inorganic and organic arsenicals, including arsenite, dimethylarsinic acid (DMAV), dimethylarsinous glutathione (DMAIIIGS), and arsenosugars. The increasing detection of thiolated arsenicals, including monomethylmonothioarsonic acid (MMMTAV), dimethylmonothioarsinic acid (DMMTAV) and its glutathione conjugate (DMMTAVGS), and dimethyldithioarsinic acid (DMDTAV) suggests that thioarsenicals may be important metabolites and play important roles in arsenic toxicity and therapeutic effects. Here we summarized the reported occurrence of thioarsenicals in biological systems, the possible formation pathways of thioarsenicals, and their toxicity, and discussed the biological implications of thioarsenicals on arsenic metabolism, toxicity, and therapeutic effects.
Collapse
Affiliation(s)
- Yuzhen Sun
- Institute of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Guangliang Liu
- Institute of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Yong Cai
- Institute of Environment and Health, Jianghan University, Wuhan 430056, China; Department of Chemistry and Biochemistry&Southeast Environmental Research Center, Florida International University, Miami, FL 33199, USA.
| |
Collapse
|
13
|
Laev SS, Salakhutdinov NF, Lavrik OI. Tyrosyl-DNA phosphodiesterase inhibitors: Progress and potential. Bioorg Med Chem 2016; 24:5017-5027. [PMID: 27687971 DOI: 10.1016/j.bmc.2016.09.045] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/30/2016] [Accepted: 09/18/2016] [Indexed: 10/21/2022]
Abstract
DNA topoisomerases are essential during transcription and replication. The therapeutic mechanism of action of topoisomerase inhibitors is enzyme poisoning rather than catalytic inhibition. Tyrosyl-DNA phosphodiesterases 1 or 2 were found as DNA repair enzymes hydrolyzing the covalent bond between the tyrosyl residue of topoisomerases I or II and the 3'- or 5'-phosphate groups in DNA, respectively. Tyrosyl-DNA phosphodiesterase 1 is a key enzyme in DNA repair machinery and a promising target for antitumor and neurodegenerative therapy. Inhibitors of tyrosyl-DNA phosphodiesterase 1 could act synergistically with topoisomerase I inhibitors and thereby potentiate the effects of topoisomerase I poisons. Tyrosyl-DNA phosphodiesterase 2 is an enzyme that specifically repairs DNA damages induced by topoisomerase II poisons and causes resistance to these drugs. Selective inhibition of tyrosyl-DNA phosphodiesterase 2 may be a novel approach to overcome intrinsic or acquired resistance to topoisomerase II-targeted drug therapy. Thus, agents that inhibit tyrosyl-DNA phosphodiesterases 1 and 2 have many applications in biochemical and physiological research and they have the potential to become anticancer and antiviral drugs. The structures, mechanism of action and therapeutic rationale of tyrosyl-DNA phosphodiesterase inhibitors and their development for combinations with topoisomerase inhibitors and DNA damaging agents are discussed.
Collapse
Affiliation(s)
- Sergey S Laev
- Vorozhtsov Institute of Organic Chemistry, Siberian Division, Russian Academy of Sciences, pr. akademika Lavrent'eva 9, Novosibirsk 630090, Russian Federation.
| | - Nariman F Salakhutdinov
- Vorozhtsov Institute of Organic Chemistry, Siberian Division, Russian Academy of Sciences, pr. akademika Lavrent'eva 9, Novosibirsk 630090, Russian Federation; Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090, Russian Federation
| | - Olga I Lavrik
- Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090, Russian Federation; Novosibirsk Institute of Chemical Biology and Fundamental Medicine, Siberian Division, Russian Academy of Sciences, pr. akademika Lavrent'eva 8, Novosibirsk 630090, Russian Federation
| |
Collapse
|
14
|
Cording A, Gormally M, Bond PJ, Carrington M, Balasubramanian S, Miska EA, Thomas B. Selective inhibitors of trypanosomal uridylyl transferase RET1 establish druggability of RNA post-transcriptional modifications. RNA Biol 2016; 14:611-619. [PMID: 26786754 PMCID: PMC5449093 DOI: 10.1080/15476286.2015.1137422] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Non-coding RNAs are crucial regulators for a vast array of cellular processes and have been implicated in human disease. These biological processes represent a hitherto untapped resource in our fight against disease. In this work we identify small molecule inhibitors of a non-coding RNA uridylylation pathway. The TUTase family of enzymes is important for modulating non-coding RNA pathways in both human cancer and pathogen systems. We demonstrate that this new class of drug target can be accessed with traditional drug discovery techniques. Using the Trypanosoma brucei TUTase, RET1, we identify TUTase inhibitors and lay the groundwork for the use of this new target class as a therapeutic opportunity for the under-served disease area of African Trypanosomiasis. In a broader sense this work demonstrates the therapeutic potential for targeting RNA post-transcriptional modifications with small molecules in human disease.
Collapse
Affiliation(s)
- Amy Cording
- a The Gurdon Institute, University of Cambridge , Cambridge , UK
| | - Michael Gormally
- b Department of Chemistry , University of Cambridge , Cambridge , UK.,c Cancer Research UK Cambridge Institute, Li Ka Shing Center , Cambridge , UK.,d National Center for Advancing Translational Sciences , National Institutes of Health , Bethesda , MD , USA
| | - Peter J Bond
- e Bioinformatics Institute (A*STAR) , Singapore.,f Department of Biological Sciences , National University of Singapore , Singapore
| | | | - Shankar Balasubramanian
- b Department of Chemistry , University of Cambridge , Cambridge , UK.,c Cancer Research UK Cambridge Institute, Li Ka Shing Center , Cambridge , UK
| | - Eric A Miska
- a The Gurdon Institute, University of Cambridge , Cambridge , UK
| | - Beth Thomas
- b Department of Chemistry , University of Cambridge , Cambridge , UK
| |
Collapse
|
15
|
Bruhn DF, Wyllie S, Rodríguez-Cortés A, Carrillo AK, Rakesh, Guy RK, Fairlamb AH, Lee RE. Pentacyclic nitrofurans that rapidly kill nifurtimox-resistant trypanosomes. J Antimicrob Chemother 2015; 71:956-63. [PMID: 26682963 DOI: 10.1093/jac/dkv417] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 11/05/2015] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES In response to reports of Trypanosoma brucei resistance to the nitroaromatic drug nifurtimox, we evaluated the potential of antituberculosis nitrofuran isoxazolines as inhibitors of trypanosome growth. METHODS The susceptibility of T. brucei brucei was assessed in vitro. The lowest effective concentration to inhibit growth (EC90) against drug-susceptible and -resistant parasites, time-kill kinetics, reversibility of inhibition and propensity for P-glycoprotein-mediated exclusion from the blood-brain barrier were determined. RESULTS Nitrofuran isoxazolines were potent inhibitors of T. brucei brucei proliferation at nanomolar concentrations, with pentacyclic nitrofurans being 100-fold more potent than nifurtimox. Activity was sustained against nifurtimox-resistant parasites, suggesting the possibility of a unique mechanism of activation and potential for use in the treatment of drug-resistant infections. Exposure of parasites to the maximum concentrations of Compound 15 achieved in vivo with oral dosing yielded >2 logs of irreversible killing in <4 h, indicating rapid trypanocidal activity. CONCLUSIONS Pentacyclic nitrofuran isoxazolines warrant further development for the treatment of drug-susceptible and nifurtimox-resistant trypanosome infections.
Collapse
Affiliation(s)
- David F Bruhn
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN, USA Avista Pharma Solutions, Durham, NC, USA
| | - Susan Wyllie
- Division of Biological Chemistry and Drug Discovery, Wellcome Trust Biocentre, College of Life Sciences, University of Dundee, Dundee, Scotland, UK
| | - Adaris Rodríguez-Cortés
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Angela K Carrillo
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Rakesh
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN, USA
| | - R Kiplin Guy
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Alan H Fairlamb
- Division of Biological Chemistry and Drug Discovery, Wellcome Trust Biocentre, College of Life Sciences, University of Dundee, Dundee, Scotland, UK
| | - Richard E Lee
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN, USA
| |
Collapse
|
16
|
Kariuki C, Kagira JM, Mwadime V, Ngotho M. Virulence and pathogenicity of three Trypanosoma brucei rhodesiense stabilates in a Swiss white mouse model. Afr J Lab Med 2015; 4:137. [PMID: 38440306 PMCID: PMC10911654 DOI: 10.4102/ajlm.v4i1.137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 08/18/2015] [Indexed: 03/06/2024] Open
Abstract
Background A key objective in basic research on human African trypanosomiasis (HAT) is developing a cheap and reliable experimental model of the disease for use in pathogenesis and drug studies. Objective With a view to improving current models, a study was undertaken to characterise the virulence and pathogenicity of three Trypanosoma brucei rhodesiense stabilates, labelled as International Livestock Research Institute (ILRI)-2918, ILRI-3953, and Institute of Primate Research (IPR)-001, infected into Swiss white mice. Methods Swiss white mice were infected intraperitoneally with trypanosomes and observed for parasitaemia using wet blood smears obtained by tail snipping. Induction of late-stage disease was undertaken using diminazene aceturate (40 mg/kg, Berenil) with curative treatment done using melarsoprol (3.6 mg/kg, Arsobal). Results The prepatent period for the stabilates ranged from three to four days with mean peak parasitaemia ranging from Log10 6.40 to 8.36. First peak parasitaemia for all stabilates varied between six and seven days post infection (DPI) followed by secondary latency in ILRI-2918 (15-17 DPI) and IPR-001 (17-19 DPI). Survival times ranged from six DPI (ILRI-3953) to 86 DPI (IPR-001). Hindleg paresis was observed in both ILRI-3953 (at peak parasitaemia) and ILRI-2918 (after relapse parasitaemia). Mice infected with IPR-001 survived until 54 DPI when curative treatment was undertaken. Conclusions This study demonstrated that the stabilates ILRI-2918 and ILRI-3953 were unsuitable for modelling late-stage HAT in mice. The stabilate IPR-001 demonstrated the potential to induce chronic trypanosomiasis in Swiss white mice for use in development of a late-stage model of HAT.
Collapse
Affiliation(s)
| | - John M. Kagira
- Jomo Kenyatta University of Agriculture and Technology,
Kenya
| | | | | |
Collapse
|
17
|
Cleghorn LAT, Albrecht S, Stojanovski L, Simeons FRJ, Norval S, Kime R, Collie IT, De Rycker M, Campbell L, Hallyburton I, Frearson JA, Wyatt PG, Read KD, Gilbert IH. Discovery of Indoline-2-carboxamide Derivatives as a New Class of Brain-Penetrant Inhibitors of Trypanosoma brucei. J Med Chem 2015; 58:7695-706. [PMID: 26418485 PMCID: PMC4601051 DOI: 10.1021/acs.jmedchem.5b00596] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
![]()
There is an urgent need for new,
brain penetrant small molecules
that target the central nervous system second stage of human African
trypanosomiasis (HAT). We report that a series of novel indoline-2-carboxamides
have been identified as inhibitors of Trypanosoma brucei from screening of a focused protease library against Trypanosoma brucei brucei in culture. We describe
the optimization and characterization of this series. Potent antiproliferative
activity was observed. The series demonstrated excellent pharmacokinetic
properties, full cures in a stage 1 mouse model of HAT, and a partial
cure in a stage 2 mouse model of HAT. Lack of tolerability prevented
delivery of a fully curative regimen in the stage 2 mouse model and
thus further progress of this series.
Collapse
Affiliation(s)
- Laura A T Cleghorn
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Sébastien Albrecht
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Laste Stojanovski
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Frederick R J Simeons
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Suzanne Norval
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Robert Kime
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Iain T Collie
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Manu De Rycker
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Lorna Campbell
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Irene Hallyburton
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Julie A Frearson
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Paul G Wyatt
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Kevin D Read
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| | - Ian H Gilbert
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee, DD1 5EH, U.K
| |
Collapse
|
18
|
Amata E, Bland ND, Campbell RK, Pollastri MP. Evaluation of pyrrolidine and pyrazolone derivatives as inhibitors of trypanosomal phosphodiesterase B1 (TbrPDEB1). Tetrahedron Lett 2015; 56:2832-2835. [PMID: 25977593 DOI: 10.1016/j.tetlet.2015.04.061] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Human African trypanosomiasis (HAT) is a parasitic disease, caused by the protozoan pathogen Trypanosoma brucei, which affects thousands every year and which is in need of new therapeutics. Herein we report the synthesis and assessment of a series of pyrrolidine and pyrazolone derivatives of human phosphodiesterase 4 (hPDE4) inhibitors for the assessment of their activity against the trypanosomal phosphodiesterase TbrPDEB1. The synthesized compounds showed weak potency against TbrPDEB1.
Collapse
Affiliation(s)
- Emanuele Amata
- Northeastern University Department of Chemistry and Chemical Biology, 417 Egan Research Center, 360 Huntington Avenue, Boston, MA 02115, USA
| | - Nicholas D Bland
- Marine Biological Laboratory, Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, 7 MBL Street, Woods Hole, MA 02543, USA
| | - Robert K Campbell
- Marine Biological Laboratory, Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, 7 MBL Street, Woods Hole, MA 02543, USA
| | - Michael P Pollastri
- Northeastern University Department of Chemistry and Chemical Biology, 417 Egan Research Center, 360 Huntington Avenue, Boston, MA 02115, USA
| |
Collapse
|
19
|
Wang QQ, Thomas DJ, Naranmandura H. Importance of being thiomethylated: formation, fate, and effects of methylated thioarsenicals. Chem Res Toxicol 2015; 28:281-9. [PMID: 25531277 DOI: 10.1021/tx500464t] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Although inorganic arsenic has long been recognized as a potent toxicant and carcinogen in humans, recent evidence shows that at least some of its effects are mediated by methylated metabolites. Elucidating the conversion of inorganic arsenic to mono-, di-, and trimethylated species has provided insights into the enzymology of this pathway and identified genetic and environmental factors that influence the susceptibility of individuals to this metalloid's adverse health effects. Notably, almost all work on the formation, fate, and effects of methylated arsenicals has focused on oxoarsenicals in which arsenic is bound to one or more oxygen atoms. However, thioarsenicals are a class of arsenicals in which a sulfur atom has replaced one or more oxygens that are bound to arsenic. Thioarsenicals have been identified as urinary metabolites in humans and other animals following exposure to inorganic arsenic. Studies find that methylated thioarsenicals exhibit kinetic behavior and toxicological properties that distinguish them from methylated oxoarsenicals. This perspective considers that formation, fate, and effects of methylated thioarsenicals with an emphasis on examining the linkages between the molecular processes that underlie both methylation and thiolation reactions. Integrating this information will provide a more comprehensive view of the relationship between the metabolism of arsenic and the risk posed by chronic exposure to this environmental contaminant.
Collapse
Affiliation(s)
- Qian Qian Wang
- Department of Toxicology, School of Medicine and Public Health, ‡College of Pharmaceutical Sciences, Zhejiang University , Hangzhou 310058, China
| | | | | |
Collapse
|
20
|
Paul A, Chai Y, Boykin DW, Wilson WD. Understanding mixed sequence DNA recognition by novel designed compounds: the kinetic and thermodynamic behavior of azabenzimidazole diamidines. Biochemistry 2014; 54:577-87. [PMID: 25495885 PMCID: PMC4303320 DOI: 10.1021/bi500989r] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Sequence-specific recognition of DNA by small organic molecules offers a potentially effective approach for the external regulation of gene expression and is an important goal in cell biochemistry. Rational design of compounds from established modules can potentially yield compounds that bind strongly and selectively with specific DNA sequences. An initial approach is to start with common A·T bp recognition molecules and build in G·C recognition units. Here we report on the DNA interaction of a synthetic compound that specifically binds to a G·C bp in the minor groove of DNA by using an azabenzimidazole moiety. The detailed interactions were evaluated with biosensor-surface plasmon resonance (SPR), isothermal calorimetric (ITC), and mass spectrometry (ESI-MS) methods. The compound, DB2277, binds with single G·C bp containing sequences with sub-nanomolar potency and displays slow dissociation kinetics and high selectivity. A detailed thermodynamic and kinetic study at different experimental salt concentrations and temperatures shows that the binding free energy is salt concentration dependent but essentially temperature independent under our experimental conditions, and binding enthalpy is temperature dependent but salt concentration independent. The results show that in the proper compound structural context novel heterocyclic cations can be designed to strongly recognize complex DNA sequences.
Collapse
Affiliation(s)
- Ananya Paul
- Department of Chemistry and Center for Diagnostics and Therapeutics, Georgia State University , Atlanta, Georgia 30303-3083, United States
| | | | | | | |
Collapse
|
21
|
Sekhar GN, Watson CP, Fidanboylu M, Sanderson L, Thomas SA. Delivery of antihuman African trypanosomiasis drugs across the blood-brain and blood-CSF barriers. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2014; 71:245-75. [PMID: 25307219 DOI: 10.1016/bs.apha.2014.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human African trypanosomiasis (HAT or sleeping sickness) is a potentially fatal disease caused by the parasite, Trypanosoma brucei sp. The parasites are transmitted by the bite of insect vectors belonging to the genus Glossina (tsetse flies) and display a life cycle strategy that is equally spread between human and insect hosts. T.b. gambiense is found in western and central Africa whereas, T.b. rhodesiense is found in eastern and southern Africa. The disease has two clinical stages: a blood stage after the bite of an infected tsetse fly, followed by a central nervous system (CNS) stage where the parasite penetrates the brain; causing death if left untreated. The blood-brain barrier (BBB) makes the CNS stage difficult to treat because it prevents 98% of all known compounds from entering the brain, including some anti-HAT drugs. Those that do enter the brain are toxic compounds in their own right and have serious side effects. There are only a few drugs available to treat HAT and those that do are stage specific. This review summarizes the incidence, diagnosis, and treatment of HAT and provides a close examination of the BBB transport of anti-HAT drugs and an overview of the latest drugs in development.
Collapse
Affiliation(s)
- Gayathri N Sekhar
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom
| | - Christopher P Watson
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom
| | - Mehmet Fidanboylu
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom
| | - Lisa Sanderson
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom
| | - Sarah A Thomas
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom.
| |
Collapse
|
22
|
Patterson S, Wyllie S. Nitro drugs for the treatment of trypanosomatid diseases: past, present, and future prospects. Trends Parasitol 2014; 30:289-98. [PMID: 24776300 PMCID: PMC4045206 DOI: 10.1016/j.pt.2014.04.003] [Citation(s) in RCA: 218] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 04/01/2014] [Accepted: 04/02/2014] [Indexed: 02/07/2023]
Abstract
Two nitro drugs are currently used in the treatment of trypanosomatid diseases. Several new nitroaromatics are being developed against the trypanosomatid diseases. Many nitro drugs and drug candidates act as prodrugs which require bioactivation. Nitroaromatics can have disparate mechanisms of action in trypanosomatid parasites.
There is an urgent need for new, safer, and effective treatments for the diseases caused by the protozoan parasites Trypanosoma brucei, Trypanosoma cruzi, and Leishmania spp. In the search for more effective drugs to treat these ‘neglected diseases’ researchers have chosen to reassess the therapeutic value of nitroaromatic compounds. Previously avoided in drug discovery programs owing to potential toxicity issues, a nitro drug is now being used successfully as part of a combination therapy for human African trypanosomiasis. We describe here the rehabilitation of nitro drugs for the treatment of trypanosomatid diseases and discuss the future prospects for this compound class.
Collapse
Affiliation(s)
- Stephen Patterson
- Division of Biological Chemistry and Drug Discovery, Sir James Black Centre, College of Life Sciences, University of Dundee, Dundee, UK.
| | - Susan Wyllie
- Division of Biological Chemistry and Drug Discovery, Wellcome Trust Biocentre, College of Life Sciences, University of Dundee, Dundee, UK.
| |
Collapse
|
23
|
Abstract
Chagas' disease is a neglected tropical disease caused by Trypanosoma cruzi and constitutes a serious public health problem for Latin America. Its unsatisfactory chemotherapy stimulates the search for novel antiparasitic compounds. Amidines and related compounds exhibit well-known activity towards different microbes including T. cruzi. In this vein, our present aim was to evaluate the biological effect of 10 novel structurally related amidines in vitro against bloodstream and intracellular forms of the parasite as well as their potential toxicity on cardiac cell cultures. Our results show that although active against the extracellular forms, with some of them like DB2247 being 6-fold more effective than benznidazole and displaying very low toxicity (>96 μm), none presented superior trypanocidal effect against intracellular forms as compared with the reference drug. These results may be due to differences in susceptibility profiles related to distinct uptake/extrusion mechanisms and cellular targets between bloodstream and amastigote forms. The present study adds to the knowledge base for the future design of novel amidines that may provide promising activity against T. cruzi.
Collapse
|
24
|
Chemoinformatic analysis as a tool for prioritization of trypanocidal marine derived lead compounds. Mar Drugs 2014; 12:1169-84. [PMID: 24599097 PMCID: PMC3967203 DOI: 10.3390/md12031169] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 01/22/2014] [Accepted: 01/30/2014] [Indexed: 11/17/2022] Open
Abstract
Marine trypanocidal natural products are, most often, reported with trypanocidal activity and selectivity against human cell lines. The triaging of hits requires a consideration of chemical tractability for drug development. We utilized a combined Lipinski's rule-of-five, chemical clustering and ChemGPS-NP principle analysis to analyze a set of 40 antitrypanosomal natural products for their drug like properties and chemical space. The analyses identified 16 chemical clusters with 11 well positioned within drug-like chemical space. This study demonstrated that our combined analysis can be used as an important strategy for prioritization of active marine natural products for further investigation.
Collapse
|
25
|
Babokhov P, Sanyaolu AO, Oyibo WA, Fagbenro-Beyioku AF, Iriemenam NC. A current analysis of chemotherapy strategies for the treatment of human African trypanosomiasis. Pathog Glob Health 2014; 107:242-52. [PMID: 23916333 DOI: 10.1179/2047773213y.0000000105] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Despite the recent advances in drug research, finding a safe, effective, and easy to use chemotherapy for human African trypanosomiasis (HAT) remains a challenging task. The four current anti-trypanosomiasis drugs have major disadvantages that limit more widespread use of these drugs in the endemic regions of sub-Saharan Africa. Pentamidine and suramin are limited by their effectiveness against the only first stage of Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense, respectively. In addition, melarsoprol and eflornithine (two second stage drugs) each have disadvantages of their own. The former is toxic and has increasing treatment failures while the latter is expensive, laborious to administer, and lacks efficacy against T. b. rhodesiense. Furthermore, melarsoprol's toxicity and decreasing efficacy are glaring problems and phasing out the drug as a frontline treatment against T. b. gambiense is now possible with the emergence of competent, safe combination chemotherapies such as nifurtimox-eflornithine combination treatment (NECT). The future of eflornithine, on the other hand, is more promising. The drug is useful in the context of combination chemotherapy and potential orally administered analogues. Due to the limits of monotherapies, greater emphasis should be placed on the research and development of combination chemotherapies, based on the successful clinical tests with NECT and its current use as a frontline anti-trypanosomiasis treatment. This review discussed the current and future chemotherapy strategies for the treatment of HAT.
Collapse
|
26
|
Chauhan K, Sharma M, Shivahare R, Debnath U, Gupta S, Prabhakar YS, Chauhan PMS. Discovery of triazine mimetics as potent antileishmanial agents. ACS Med Chem Lett 2013; 4:1108-13. [PMID: 24900613 DOI: 10.1021/ml400317e] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 10/01/2013] [Indexed: 01/16/2023] Open
Abstract
The World Health Organization has classified the leishmaniasis as a major tropical disease. The discovery of new compounds for leishmaniasis is therefore a pressing concern for the anti-infective research program. We have synthesized 19 compounds of triazine dimers as novel antileishmanial agents. Most of the synthesized derivatives exhibited better activity against intracellular amastigotes (IC50 ranging from 0.77 to 10.32 μM) than the control, pentamidine (IC50 = 13.68 μM), and are not toxic to Vero cells. Compounds 14 and 15 showed significant in vivo inhibition of 74.41% and 62.64%, respectively, in L. donovani/hamster model. Moreover, expansion of Th1-type and suppression of Th2-type immune responses proved that compound 14 stimulates mouse macrophages to prevent the progression of leishmania parasite. The molecular docking studies involving PTR1 protein PDB further validated the concepts involved in the design of these compounds. Among the investigated analogues, compound 14 has emerged as the potential one to enlarge the scope of the study.
Collapse
Affiliation(s)
- Kuldeep Chauhan
- Medicinal and Process Chemistry Division and ‡Division of Parasitology, CSIR—Central Drug Research Institute, Lucknow 226031, U.P., India
| | - Moni Sharma
- Medicinal and Process Chemistry Division and ‡Division of Parasitology, CSIR—Central Drug Research Institute, Lucknow 226031, U.P., India
| | - Rahul Shivahare
- Medicinal and Process Chemistry Division and ‡Division of Parasitology, CSIR—Central Drug Research Institute, Lucknow 226031, U.P., India
| | - Utsab Debnath
- Medicinal and Process Chemistry Division and ‡Division of Parasitology, CSIR—Central Drug Research Institute, Lucknow 226031, U.P., India
| | - Suman Gupta
- Medicinal and Process Chemistry Division and ‡Division of Parasitology, CSIR—Central Drug Research Institute, Lucknow 226031, U.P., India
| | - Yenamandra S. Prabhakar
- Medicinal and Process Chemistry Division and ‡Division of Parasitology, CSIR—Central Drug Research Institute, Lucknow 226031, U.P., India
| | - Prem M. S. Chauhan
- Medicinal and Process Chemistry Division and ‡Division of Parasitology, CSIR—Central Drug Research Institute, Lucknow 226031, U.P., India
| |
Collapse
|
27
|
Abstract
BACKGROUND Human African trypanosomiasis, or sleeping sickness, is a painful and protracted disease affecting people in the poorest parts of Africa and is fatal without treatment. Few drugs are currently available for second-stage sleeping sickness, with considerable adverse events and variable efficacy. OBJECTIVES To evaluate the effectiveness and safety of drugs for treating second-stage human African trypanosomiasis. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register (January 2013), CENTRAL (The Cochrane Library Issue 12 2012) , MEDLINE (1966 to January 2013), EMBASE (1974 to January 2013), LILACS (1982 to January 2013 ), BIOSIS (1926-January 2013), mRCT (January 2013) and reference lists. We contacted researchers working in the field and organizations. SELECTION CRITERIA Randomized and quasi-randomized controlled trials including adults and children with second-stage HAT, treated with anti-trypanosomal drugs. DATA COLLECTION AND ANALYSIS Two authors (VL and AK) extracted data and assessed methodological quality; a third author (JS) acted as an arbitrator. Included trials only reported dichotomous outcomes, and we present these as risk ratio (RR) with 95% confidence intervals (CI). MAIN RESULTS Nine trials with 2577 participants, all with Trypansoma brucei gambiense HAT, were included. Seven trials tested currently available drugs: melarsoprol, eflornithine, nifurtimox, alone or in combination; one trial tested pentamidine, and one trial assessed the addition of prednisolone to melarsoprol. The frequency of death and number of adverse events were similar between patients treated with fixed 10-day regimens of melarsoprol or 26-days regimens. Melarsoprol monotherapy gave fewer relapses than pentamidine or nifurtimox, but resulted in more adverse events.Later trials evaluate nifurtimox combined with eflornithine (NECT), showing this gives few relapses and is well tolerated. It also has practical advantages in reducing the frequency and number of eflornithine slow infusions to twice a day, thus easing the burden on health personnel and patients. AUTHORS' CONCLUSIONS Choice of therapy for second stage Gambiense HAT will continue to be determined by what is locally available, but eflornithine and NECT are likely to replace melarsoprol, with careful parasite resistance monitoring. We need research on reducing adverse effects of currently used drugs, testing different regimens, and experimental and clinical studies of new compounds, effective for both stages of the disease.
Collapse
Affiliation(s)
- Vittoria Lutje
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK.
| | | | | |
Collapse
|
28
|
Lozano-Núñez A, Ikeda KN, Sauer T, de Graffenried CL. An analogue-sensitive approach identifies basal body rotation and flagellum attachment zone elongation as key functions of PLK in Trypanosoma brucei. Mol Biol Cell 2013; 24:1321-33. [PMID: 23447704 PMCID: PMC3639044 DOI: 10.1091/mbc.e12-12-0846] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The Polo-like kinase homologue in Trypanosoma brucei (TbPLK) regulates the assembly of a series of organelles necessary for positioning the parasite's flagellum. An analogue-sensitive strategy is used to acutely and specifically inhibit the kinase with a small molecule, making it possible to identify novel TbPLK functions. Polo-like kinases are important regulators of cell division, playing diverse roles in mitosis and cytoskeletal inheritance. In the parasite Trypanosoma brucei, the single PLK homologue TbPLK is necessary for the assembly of a series of essential organelles that position and adhere the flagellum to the cell surface. Previous work relied on RNA interference or inhibitors of undefined specificity to inhibit TbPLK, both of which have significant experimental limitations. Here we use an analogue-sensitive approach to selectively and acutely inhibit TbPLK. T. brucei cells expressing only analogue-sensitive TbPLK (TbPLKas) grow normally, but upon treatment with inhibitor develop defects in flagellar attachment and cytokinesis. TbPLK cannot migrate effectively when inhibited and remains trapped in the posterior of the cell throughout the cell cycle. Using synchronized cells, we show that active TbPLK is a direct requirement for the assembly and extension of the flagellum attachment zone, which adheres the flagellum to the cell surface, and for the rotation of the duplicated basal bodies, which positions the new flagellum so that it can extend without impinging on the old flagellum. This approach should be applicable to the many kinases found in the T. brucei genome that lack an ascribed function.
Collapse
Affiliation(s)
- Ana Lozano-Núñez
- Max F. Perutz Laboratories, Center for Molecular Biology, University of Vienna, 1030 Vienna, Austria
| | | | | | | |
Collapse
|
29
|
Abstract
Arsenic has received considerable attention in the world, since it can lead to a multitude of toxic effects and has been recognized as a human carcinogen causing cancers. Here, we focus on the current state of knowledge regarding the proposed mechanisms of arsenic biotransformation, with a little about cellular uptake, toxicity and clinical utilization of arsenicals. Since pentavalent methylated metabolites were found in animal urine after exposure to iAs(III), methylation was considered to be a detoxification process, but the discovery of methylated trivalent intermediates and thioarsenicals in urine has diverted the view and gained much interest regarding arsenic biotransformation. To further investigate the partially understood phenomena relating to arsenic toxicity and the uses of arsenic as a drug, it is important to elucidate the exact pathways involved in metabolism of this metalloid, as the toxicity and the clinical uses of arsenic can be best recognized in context of its biotransformation. Thereby, in this perspective, we have focused on arsenic metabolic pathways including three proposed mechanisms: a classic pathway by Challenger in 1945, followed by a new metabolic pathway proposed by Hayakawa in 2005 involving arsenic-glutathione complexes, while the third is a new reductive methylation pathway that is proposed by our group involving As-protein complexes. According to previous and present in vivo and in vitro experiments, we conclude that the methylation reaction takes place with simultaneous reductive rather than stepwise oxidative methylation. In addition, production of pentavalent methylated arsenic metabolites are suggested to be as the end product of metabolism, rather than intermediates.
Collapse
Affiliation(s)
- Kanwal Rehman
- Department of Pharmacology, Toxicology, and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, 310561, China
| | | |
Collapse
|
30
|
Bouteille B, Buguet A. The detection and treatment of human African trypanosomiasis. Res Rep Trop Med 2012; 3:35-45. [PMID: 30890865 DOI: 10.2147/rrtm.s24751] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Human African trypanosomiasis (HAT) is caused by the injection of Trypanosoma brucei (T. b.) gambiense or T. b. rhodesiense by Glossina, the tsetse fly. Three historical eras followed the exclusive clinical approach of the 19th century. At the turn of the century, the "initial research" era was initiated because of the dramatic spread of HAT throughout intertropical Africa, and scientists discovered the agent and its vector. Two entities, recurrent fever and sleeping sickness, were then considered a continuum between hemolymphatic stage 1 and meningoencephalitic stage 2. Treatments were developed. Soon after World War I, specific services and mobile teams were created, initiating the "epidemiological" era, during which populations were visited, screened, and treated. As a result, by 1960, annual new cases were rare. New mass screening and staging tools were then developed in a third, "modern" era, especially to counter a new epidemic wave. Currently, diagnosis still relies on microscopic detection of trypanosomes without (wet and thick blood films) or with concentration techniques (capillary tube centrifugation, miniature anion-exchange centrifugation technique). Staging is a vital step. Stage 1 patients are treated on site with pentamidine or suramin. However, stage 2 patients are treated in specialized facilities, using drugs that are highly toxic and/or that require complex administration procedures (melarsoprol, eflornithine, or nifurtimox-eflornithine combination therapy). Suramin and melarsoprol are the only medications active against Rhodesian HAT. Staging still relies on cerebrospinal fluid examination for trypanosome detection and white blood cell counts: stage 1, absence of trypanosomes, white blood cell counts ≤ 5/µL; stage 2, presence of trypanosomes, white blood cell counts ≥ 20/µL; T. b. gambiense HAT intermediate stage, between these still controversial thresholds. Our group has proposed the use of noninvasive ambulatory polysomnography to identify sleep-wake abnormalities characteristic of stage 2 of the disease. Only patients with abnormal sleep-wake patterns would then undergo confirmative lumbar puncture.
Collapse
Affiliation(s)
- Bernard Bouteille
- Laboratory of Parasitology, Dupuytren University Hospital of Limoges, France,
| | - Alain Buguet
- Polyclinic Marie-Louise Poto-Djembo, Pointe-Noire, Congo
| |
Collapse
|
31
|
Feng Y, Davis RA, Sykes ML, Avery VM, Quinn RJ. Iotrochamides A and B, antitrypanosomal compounds from the Australian marine sponge Iotrochota sp. Bioorg Med Chem Lett 2012; 22:4873-6. [PMID: 22677313 DOI: 10.1016/j.bmcl.2012.05.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 05/04/2012] [Accepted: 05/08/2012] [Indexed: 10/28/2022]
Abstract
Bioassay-guided isolation of the CH(2)Cl(2)/MeOH extract from the Australian sponge Iotrochota sp. resulted in the purification of two new N-cinnamoyl-amino acids, iotrochamides A (1) and B (2). The chemical structures of 1 and 2 were determined by 1D/2D NMR and MS data analyses. Compounds 1 and 2 were shown to inhibit Trypanosoma brucei brucei with IC(50) values of 3.4 and 4.7 μM, respectively.
Collapse
Affiliation(s)
- Yunjiang Feng
- Eskitis Institute, Griffith University, Brisbane, QLD 4111, Australia
| | | | | | | | | |
Collapse
|
32
|
Correlation of acetylcholinesterase activity in the brain and blood of wistar rats acutely infected with Trypanosoma congolense. JOURNAL OF ACUTE DISEASE 2012. [DOI: 10.1016/s2221-6189(13)60006-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
33
|
Watson CP, Dogruel M, Mihoreanu L, Begley DJ, Weksler BB, Couraud PO, Romero IA, Thomas SA. The transport of nifurtimox, an anti-trypanosomal drug, in an in vitro model of the human blood-brain barrier: evidence for involvement of breast cancer resistance protein. Brain Res 2011; 1436:111-21. [PMID: 22200378 PMCID: PMC3281990 DOI: 10.1016/j.brainres.2011.11.053] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 11/07/2011] [Accepted: 11/28/2011] [Indexed: 01/16/2023]
Abstract
Human African trypanosomiasis (HAT) is a parasitic disease affecting sub-Saharan Africa. The parasites are able to traverse the blood–brain barrier (BBB), which marks stage 2 (S2) of the disease. Delivery of anti-parasitic drugs across the BBB is key to treating S2 effectively and the difficulty in achieving this goal is likely to be a reason why some drugs require highly intensive treatment regimes to be effective. This study aimed to investigate not only the drug transport mechanisms utilised by nifurtimox at the BBB, but also the impact of nifurtimox–eflornithine combination therapy (NECT) and other anti-HAT drug combination therapies (CTs) on radiolabelled-nifurtimox delivery in an in vitro model of drug accumulation and the human BBB, the hCMEC/D3 cell line. We found that nifurtimox appeared to use several membrane transporters, in particular breast-cancer resistance protein (BCRP), to exit the BBB cells. The addition of eflornithine caused no change in the accumulation of nifurtimox, nor did the addition of clinically relevant doses of the other anti-HAT drugs suramin, nifurtimox or melarsoprol, but a significant increase was observed with the addition of pentamidine. The results provide evidence that anti-HAT drugs are interacting with membrane transporters at the human BBB and suggest that combination with known transport inhibitors could potentially improve their efficacy.
Collapse
Affiliation(s)
- Christopher P Watson
- King's College London, Institute of Pharmaceutical Science, Waterloo, London, UK
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Nissapatorn V, Sawangjaroen N. Parasitic infections in HIV infected individuals: diagnostic & therapeutic challenges. Indian J Med Res 2011; 134:878-97. [PMID: 22310820 PMCID: PMC3284096 DOI: 10.4103/0971-5916.92633] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Indexed: 12/30/2022] Open
Abstract
After 30 years of the human immunodeficiency virus (HIV) epidemic, parasites have been one of the most common opportunistic infections (OIs) and one of the most frequent causes of morbidity and mortality associated with HIV-infected patients. Due to severe immunosuppression, enteric parasitic pathogens in general are emerging and are OIs capable of causing diarrhoeal disease associated with HIV. Of these, Cryptosporidium parvum and Isospora belli are the two most common intestinal protozoan parasites and pose a public health problem in acquired immunodeficiency syndrome (AIDS) patients. These are the only two enteric protozoan parasites that remain in the case definition of AIDS till today. Leishmaniasis, strongyloidiasis and toxoplasmosis are the three main opportunistic causes of systemic involvements reported in HIV-infected patients. Of these, toxoplasmosis is the most important parasitic infection associated with the central nervous system. Due to its complexity in nature, toxoplasmosis is the only parasitic disease capable of not only causing focal but also disseminated forms and it has been included in AIDS-defining illnesses (ADI) ever since. With the introduction of highly active anti-retroviral therapy (HAART), cryptosporidiosis, leishmaniasis, schistosomiasis, strongyloidiasis, and toxoplasmosis are among parasitic diseases reported in association with immune reconstitution inflammatory syndrome (IRIS). This review addresses various aspects of parasitic infections in term of clinical, diagnostic and therapeutic challenges associated with HIV-infection.
Collapse
Affiliation(s)
- Veeranoot Nissapatorn
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | | |
Collapse
|
35
|
Paliwal SK, Verma AN, Paliwal S. Structure–activity relationship analysis of cationic 2-phenylbenzofurans as potent anti-trypanosomal agents: a multivariate statistical approach. MONATSHEFTE FUR CHEMIE 2011. [DOI: 10.1007/s00706-011-0509-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
36
|
Paliwal SK, Verma AN, Paliwal S. Neglected disease - african sleeping sickness: recent synthetic and modeling advances. Sci Pharm 2011; 79:389-428. [PMID: 21886894 PMCID: PMC3163371 DOI: 10.3797/scipharm.1012-08] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 05/10/2011] [Indexed: 01/21/2023] Open
Abstract
Human African Trypanosomiasis (HAT) also called sleeping sickness is caused by subspecies of the parasitic hemoflagellate Trypanosoma brucei that mostly occurs in sub-Saharan Africa. The current chemotherapy of the human trypanosomiases relies on only six drugs, five of which have been developed more than 30 years ago, have undesirable toxic side effects and most of them show drug-resistance. Though development of new anti-trypanosomal drugs seems to be a priority area research in this area has lagged far behind. The given review mainly focus upon the recent synthetic and computer based approaches made by various research groups for the development of newer anti-trypanosomal analogues which may have improved efficacy and oral bioavailability than the present ones. The given paper also attempts to investigate the relationship between the various physiochemical parameters and anti-trypanosomal activity that may be helpful in development of potent anti-trypanosomal agents against sleeping sickness.
Collapse
|
37
|
Abstract
Arsenic is a metalloid that is considered to be a paradox in terms of its role both as a carcinogen and as a therapeutic agent. Chronic exposure to arsenic in drinking water has been linked with the development of various pathological conditions including cancer. Nevertheless, the therapeutic potential of arsenic and its derivatives in a variety of diseases have been exploited in the past. However, its role and mechanism of action as a therapeutic agent still remain an active area of research and investigation. Our ongoing work also suggests varied responses in cancer cells exposed to lower versus higher concentrations of arsenic. Furthermore, the arsenic combinations with chemopreventive or anticancer agents have been observed to sensitize the cell for cell-cycle arrest and cell death. Here, we have provided the account of recent updates on the mechanism of action of arsenic and its derivatives that lead to various disorders, and its role as a therapeutic agent both as a single agent as well as in combination chemotherapy.
Collapse
|
38
|
Oduor RO, Ojo KK, Williams GP, Bertelli F, Mills J, Maes L, Pryde DC, Parkinson T, Van Voorhis WC, Holler TP. Trypanosoma brucei glycogen synthase kinase-3, a target for anti-trypanosomal drug development: a public-private partnership to identify novel leads. PLoS Negl Trop Dis 2011; 5:e1017. [PMID: 21483717 PMCID: PMC3071371 DOI: 10.1371/journal.pntd.0001017] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 02/06/2011] [Indexed: 11/28/2022] Open
Abstract
Background Trypanosoma brucei, the causative agent of Human African Trypanosomiasis (HAT), expresses two proteins with homology to human glycogen synthase kinase 3β (HsGSK-3) designated TbruGSK-3 short and TbruGSK-3 long. TbruGSK-3 short has previously been validated as a potential drug target and since this enzyme has also been pursued as a human drug target, a large number of inhibitors are available for screening against the parasite enzyme. A collaborative industrial/academic partnership facilitated by the World Health Organisation Tropical Diseases Research division (WHO TDR) was initiated to stimulate research aimed at identifying new drugs for treating HAT. Methodology/Principal Findings A subset of over 16,000 inhibitors of HsGSK-3 β from the Pfizer compound collection was screened against the shorter of two orthologues of TbruGSK-3. The resulting active compounds were tested for selectivity versus HsGSK-3β and a panel of human kinases, as well as in vitro anti-trypanosomal activity. Structural analysis of the human and trypanosomal enzymes was also performed. Conclusions/Significance We identified potent and selective compounds representing potential attractive starting points for a drug discovery program. Structural analysis of the human and trypanosomal enzymes also revealed hypotheses for further improving selectivity of the compounds. Over 60 million people in sub-Saharan Africa are at risk of infection with the parasite Trypanosoma brucei which causes Human African Trypanosomiasis (HAT), also known as sleeping sickness. The disease results in systemic and neurological disability to its victims. At present, only four drugs are available for treatment of HAT. However, these drugs are expensive, limited in efficacy and are severely toxic, hence the need to develop new therapies. Previously, the short TbruGSK-3 short has been validated as a potential target for developing new drugs against HAT. Because this enzyme has also been pursued as a drug target for other diseases, several inhibitors are available for screening against the parasite enzyme. Here we present the results of screening over 16,000 inhibitors of human GSK-3β (HsGSK-3) from the Pfizer compound collection against TbruGSK-3 short. The resulting active compounds were tested for selectivity versus HsGSK-3β and a panel of human kinases, as well as their ability to inhibit proliferation of the parasite in vitro. We have identified attractive compounds that now form potential starting points for drug discovery against HAT. This is an example of how a tripartite partnership involving pharmaceutical industries, academic institutions and non-government organisations such as WHO TDR, can stimulate research for neglected diseases.
Collapse
Affiliation(s)
- Richard O. Oduor
- Opportunities for Partnering in Medicine, Pfizer Global Research and Development, Sandwich, Kent, United Kingdom
| | - Kayode K. Ojo
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, United States of America
| | - Gareth P. Williams
- High Throughput Screening Center of Emphasis, Pfizer Global Research and Development, Sandwich, Kent, United Kingdom
| | - Francois Bertelli
- High Throughput Screening Center of Emphasis, Pfizer Global Research and Development, Sandwich, Kent, United Kingdom
| | - James Mills
- Worldwide Medicinal Chemistry, Pfizer Global Research and Development, Sandwich, Kent, United Kingdom
| | - Louis Maes
- Laboratory for Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium
| | - David C. Pryde
- Worldwide Medicinal Chemistry, Pfizer Global Research and Development, Sandwich, Kent, United Kingdom
| | - Tanya Parkinson
- Opportunities for Partnering in Medicine, Pfizer Global Research and Development, Sandwich, Kent, United Kingdom
- * E-mail:
| | - Wesley C. Van Voorhis
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, United States of America
| | - Tod P. Holler
- Opportunities for Partnering in Medicine, Pfizer Global Research and Development, Sandwich, Kent, United Kingdom
| |
Collapse
|
39
|
Abstract
Glutathione transferases (GSTs) are a multigene family of ubiquitously expressed, polymorphic enzymes responsible for the metabolism of a wide range of both endogenous and exogenous substrates, play a central role in the adaptive response to chemical and oxidative stress, and are subject to regulation by a range of structurally unrelated chemicals. In this review, we present a current summary of knockout mouse models in the GST field, discussing some of the issues pertaining to orthologous proteins between mice and humans, the potential confounding issues related to genetic background, and also cover new transgenic models in the increasingly important area of humanization.
Collapse
Affiliation(s)
- Colin J Henderson
- Cancer Research UK, Molecular Pharmacology Group, Biomedical Research Institute, University of Dundee College of Medicine Dentistry and Nursing, Ninewells Hospital, Dundee, United Kingdom.
| | | |
Collapse
|
40
|
Srivastava HK, Chourasia M, Kumar D, Sastry GN. Comparison of Computational Methods to Model DNA Minor Groove Binders. J Chem Inf Model 2011; 51:558-71. [DOI: 10.1021/ci100474n] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Hemant Kumar Srivastava
- Molecular Modelling Group, Indian Institute of Chemical Technology, Taranaka, Hyderabad 500 607, India
| | - Mukesh Chourasia
- Molecular Modelling Group, Indian Institute of Chemical Technology, Taranaka, Hyderabad 500 607, India
| | - Devesh Kumar
- Molecular Modelling Group, Indian Institute of Chemical Technology, Taranaka, Hyderabad 500 607, India
| | - G. Narahari Sastry
- Molecular Modelling Group, Indian Institute of Chemical Technology, Taranaka, Hyderabad 500 607, India
| |
Collapse
|
41
|
Kroubi M, Daulouede S, Karembe H, Jallouli Y, Howsam M, Mossalayi D, Vincendeau P, Betbeder D. Development of a nanoparticulate formulation of diminazene to treat African trypanosomiasis. NANOTECHNOLOGY 2010; 21:505102. [PMID: 21098928 DOI: 10.1088/0957-4484/21/50/505102] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
There is a real need to develop new therapeutic strategies for African trypanosomiasis infections. In our study, we developed a new drug delivery system of diminazene (DMZ), a trypanocidal drug registered for veterinary use. This drug candidate presents a limited efficacy, a poor affinity for brain tissue and instability. The development of colloidal formulations based on a porous cationic nanoparticle with an oily core ((70)DGNP(+)), has potentially two advantages: stabilization of the drug and potential targeting of the parasite. We analyzed two processes of drug loading: in process (DMZ was added during the preparation of (70)DGNP(+) at 80 °C) and post-loading (DMZ was mixed with a (70)DGNP(+) solution at room temperature). Poor stability of the drug was observed using the in process technique. When using the post-loading technique over 80% drug entrapment efficiency was obtained at a ratio of DMZ:phospholipids (wt:wt) < 5%. Moreover, DMZ loaded into (70)DGNP(+) was found to be protected against oxidation and was stable for at least six months at 4 °C. Finally, in vitro tests on T.b. brucei showed an increased efficacy of DMZ loaded in (70)DGNP(+).
Collapse
Affiliation(s)
- Maya Kroubi
- EA 4483, IFR 114 IMPRT, Faculté de Médecine, Pôle recherche, Département de Physiologie, 1 place de Verdun, 59045 Lille Cedex, France
| | | | | | | | | | | | | | | |
Collapse
|
42
|
Barratt JLN, Harkness J, Marriott D, Ellis JT, Stark D. Importance of nonenteric protozoan infections in immunocompromised people. Clin Microbiol Rev 2010; 23:795-836. [PMID: 20930074 PMCID: PMC2952979 DOI: 10.1128/cmr.00001-10] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
There are many neglected nonenteric protozoa able to cause serious morbidity and mortality in humans, particularly in the developing world. Diseases caused by certain protozoa are often more severe in the presence of HIV. While information regarding neglected tropical diseases caused by trypanosomatids and Plasmodium is abundant, these protozoa are often not a first consideration in Western countries where they are not endemic. As such, diagnostics may not be available in these regions. Due to global travel and immigration, this has become an increasing problem. Inversely, in certain parts of the world (particularly sub-Saharan Africa), the HIV problem is so severe that diseases like microsporidiosis and toxoplasmosis are common. In Western countries, due to the availability of highly active antiretroviral therapy (HAART), these diseases are infrequently encountered. While free-living amoebae are rarely encountered in a clinical setting, when infections do occur, they are often fatal. Rapid diagnosis and treatment are essential to the survival of patients infected with these organisms. This paper reviews information on the diagnosis and treatment of nonenteric protozoal diseases in immunocompromised people, with a focus on patients infected with HIV. The nonenteric microsporidia, some trypanosomatids, Toxoplasma spp., Neospora spp., some free-living amoebae, Plasmodium spp., and Babesia spp. are discussed.
Collapse
Affiliation(s)
- J L N Barratt
- Department of Microbiology, St. Vincent's Hospital, Darlinghurst 2010, NSW, Australia.
| | | | | | | | | |
Collapse
|
43
|
Abstract
BACKGROUND Human African trypanosomiasis, or sleeping sickness, is a painful and protracted disease affecting people in the poorest parts of Africa and is fatal without treatment. Few drugs are currently available for second-stage sleeping sickness, with considerable adverse events and variable efficacy. OBJECTIVES To evaluate the effectiveness and safety of drugs for treating second-stage human African trypanosomiasis. SEARCH STRATEGY We searched the Cochrane Infectious Diseases Group Specialized Register (May 2010), CENTRAL (The Cochrane Library Issue 3 2010) , MEDLINE (1966 to May 2010), EMBASE (1974 to May 2010), LILACS (1982 to May 2010 ), BIOSIS (1926-May 2010), mRCT (May 2010) and reference lists. We contacted researchers working in the field and organizations. SELECTION CRITERIA Randomized and quasi-randomized controlled trials. DATA COLLECTION AND ANALYSIS Two authors (VL and AK) extracted data and assessed methodological quality; a third author (JS) acted as an arbitrator. Included trials only reported dichotomous outcomes, and we present these as risk ratio (RR) with 95% confidence intervals (CI). MAIN RESULTS Nine trials with 2577 participants, all with Trypansoma brucei gambiense HAT, were included. Seven trials tested currently available drugs: melarsoprol, eflornithine, nifurtimox, alone or in combination; one trial tested pentamidine, and one trial assessed the addition of prednisolone to melarsoprol. Fixed 10-day regimens of melarsoprol were found to be as effective as those of 26 days, with similar numbers of adverse events. Melarsoprol monotherapy gave fewer relapses than pentamidine or nifurtimox, but resulted in more adverse events.Later trials evaluate nifurtimox combined with eflornithine (NECT), showing this gives few relapses and is well tolerated. It also has practical advantages in reducing the burden on health personnel and patients, when compared to eflornithine monotherapy. AUTHORS' CONCLUSIONS Choice of therapy for second stage Gambiense HAT will continue to be determined by what is locally available, but eflornithine and NECT are likely to replace melarsoprol, with careful parasite resistance monitoring. We need research on reducing adverse effects of currently used drugs, testing different regimens, and experimental and clinical studies of new compounds, effective for both stages of the disease.
Collapse
Affiliation(s)
- Vittoria Lutje
- International Health Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK, L3 5QA
| | | | | |
Collapse
|
44
|
Amin DN, Ngoyi DM, Nhkwachi GM, Palomba M, Rottenberg M, Büscher P, Kristensson K, Masocha W. Identification of stage biomarkers for human African trypanosomiasis. Am J Trop Med Hyg 2010; 82:983-90. [PMID: 20519589 DOI: 10.4269/ajtmh.2010.09-0770] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Human African trypanosomiasis (HAT), caused by infection with sub-species of Trypanosoma brucei (T. b.), manifests as a hemolymphatic stage followed by an encephalitic stage. The distinction of the two stages needs improvement as drugs used for the late stage are highly toxic. Transcripts encoding 16 secreted proteins differentially expressed in the brains of mice at late stage T. b. brucei infection when the early stage drug suramin is no longer effective and different to immunoglobulins, chemokines, and cytokines, were selected by microarray analysis. Lipocalin 2 and secretory leukocyte peptidase inhibitor (SLPI) mRNA showed the highest differential expression in mice. These transcripts were also upregulated in brains from infected rats. Lipocalin 2 was increased in cerebrospinal fluid (CSF) from rats during late stage T. b. brucei infection. Protein levels of lipocalin 2, SLPI, and the chemokine CXCL10 were found increased in CSF from Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense late stage HAT compared to early stage.
Collapse
Affiliation(s)
- Daniel Ndem Amin
- Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77 Sweden.
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Branowska D, Farahat AA, Kumar A, Wenzler T, Brun R, Liu Y, Wilson WD, Boykin DW. Synthesis and antiprotozoal activity of 2,5-bis[amidinoaryl]thiazoles. Bioorg Med Chem 2010; 18:3551-8. [PMID: 20403703 PMCID: PMC2892117 DOI: 10.1016/j.bmc.2010.03.058] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 03/23/2010] [Accepted: 03/24/2010] [Indexed: 10/19/2022]
Abstract
Seven novel diamidino 2,5-bis(aryl)thiazoles (5a-g) were synthesized and evaluated against Trypanosoma brucei rhodensiense (T. b. r.) and Plasmodium falciparum (P. f.). The diamidines were obtained directly from the corresponding bis-nitriles (4a-g) by the action of lithium bis(trimethylsilyl)amide. The bis-nitriles 4a-f were synthesized in four steps starting with the Stille coupling of 2-tributyltinthiazole with the appropriate cyanoaryl halide. The bis-nitrile 5g was obtained by the palladium facilitated coupling of the mixed tin-silyl reagent 2-trimethylsilyl-5-trimethyltinthiazole with 2-bromo-5-cyanopyridine. The amidoxime potential prodrugs 6a-e, 6g were obtained by the reaction of hydroxylamine with the bis-nitriles. O-Methylation of the amidoximes gave the corresponding N-methoxyamidines 7a-c, 7e, 7g. The diamidines showed strong DNA binding affinity as reflected by DeltaT(m) measurements. Four of the diamidines 5a, 5b, 5d and 5e were highly active in vitro against P. f. giving IC(50) values between 1.1 and 2.5nM. The same four diamidines showed IC(50) values between 4 and 6nM against T. b. r. The selectivity indices ranged from 233 to 9175. One diamidine 5a produced one of four cures at an ip dose of 4x5mg/kg in the STIB900 mouse model for acute African trypanosomiasis. The amidoxime and N-methoxyamidine of 5a were the only produgs to provide cures (1/4 cures) in the same mouse model on oral dosage at 4x25mg/kg.
Collapse
Affiliation(s)
- Danuta Branowska
- Department of Chemistry, Georgia State University, Atlanta, GA 30303-3083, USA
| | | | | | | | | | | | | | | |
Collapse
|
46
|
Cross-resistance to nitro drugs and implications for treatment of human African trypanosomiasis. Antimicrob Agents Chemother 2010; 54:2893-900. [PMID: 20439607 DOI: 10.1128/aac.00332-10] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The success of nifurtimox-eflornithine combination therapy (NECT) for the treatment of human African trypanosomiasis (HAT) has renewed interest in the potential of nitro drugs as chemotherapeutics. In order to study the implications of the more widespread use of nitro drugs against these parasites, we examined the in vivo and in vitro resistance potentials of nifurtimox and fexinidazole and its metabolites. Following selection in vitro by exposure to increasing concentrations of nifurtimox, Trypanosoma brucei brucei nifurtimox-resistant clones designated NfxR1 and NfxR2 were generated. Both cell lines were found to be 8-fold less sensitive to nifurtimox than parental cells and demonstrated cross-resistance to a number of other nitro drugs, most notably the clinical trial candidate fexinidazole (approximately 27-fold more resistant than parental cells). Studies of mice confirmed that the generation of nifurtimox resistance in these parasites did not compromise virulence, and NfxR1 remained resistant to both nifurtimox and fexinidazole in vivo. In the case of fexinidazole, drug metabolism and pharmacokinetic studies indicate that the parent drug is rapidly metabolized to the sulfoxide and sulfone form of this compound. These metabolites retained trypanocidal activity but were less effective in nifurtimox-resistant lines. Significantly, trypanosomes selected for resistance to fexinidazole were 10-fold more resistant to nifurtimox than parental cells. This reciprocal cross-resistance has important implications for the therapeutic use of nifurtimox in a clinical setting and highlights a potential danger in the use of fexinidazole as a monotherapy.
Collapse
|
47
|
|
48
|
Metalloid transport by aquaglyceroporins: consequences in the treatment of human diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 679:57-69. [PMID: 20666224 DOI: 10.1007/978-1-4419-6315-4_5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Metalloids can severely harm human physiology in a toxicological sense if taken up from the environment in acute high doses or chronically. However, arsenic or antimony containing drugs are still being used as treatment and are often the sole regime for certain forms of cancer, mainly types of leukemia and diseases caused by parasites, such as sleeping sickness or leishmaniasis. In this chapter, we give an outline of the positive effects of arsenicals and antimonials against such diseases, we summarize data on uptake pathways through human and parasite aquaglyceroporins and we discuss the progress and options in the development of therapeutic aquaporin and aquaglyceroporin inhibitor compounds.
Collapse
|
49
|
Paliwal S, Narayan A, Paliwal S. Quantitative Structure Activity Relationship Analysis of Dicationic Diphenylisoxazole as Potent Anti-Trypanosomal Agents. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/qsar.200860206] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
50
|
Cerebrospinal fluid B lymphocyte identification for diagnosis and follow-up in human African trypanosomiasis in the field. Trop Med Int Health 2009; 15:454-61. [PMID: 19807900 DOI: 10.1111/j.1365-3156.2009.02400.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES In human African trypanosomiasis (HAT, sleeping sickness), staging of disease and treatment follow-up relies on white cell count in the cerebrospinal fluid (CSF). As B lymphocytes (CD19 positive cells) are not found in the CSF of healthy individuals but occur in neurological disorders such as multiple sclerosis, B lymphocyte count may be useful for field diagnosis/staging and therapeutic follow-up in HAT. METHODS Seventy-one HAT patients were diagnosed and 50 were followed-up 6-24 months after treatment. White cell counts were used for conventional staging (stage 1, < or =5 cells/microl CSF, n = 42; stage 2, > or =20 cells/microl, n = 16) and intermediate stage (6-19 cells/microl, n = 13). Slides containing 1 microl of CSF mixed with Dynabeads CD19 pan B were examined microscopically to detect B cell rosettes (bound to at least four beads). RESULTS Stage 1 patients exhibited zero (n = 37) or one CSF rosette/microl (n = 5), contrary to most stage 2 patients (14/16: > or =2 rosettes/microl). Intermediate stage patients expressed 0 (n = 9), 1 (n = 3) or 2 (n = 1) rosettes/microl of CSF. During follow-up, rosette counts correlated with white cell count staging but were much easier to read. CONCLUSION B cell rosettes being easily detected in the CSF in field conditions may be proposed to replace white cell count for defining HAT stages 1 and 2 and limit uncertainty in treatment decision in patients with intermediate stage.
Collapse
|