51
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Molecular surveillance of pvdhfr, pvdhps, and pvmdr-1 mutations in Plasmodium vivax isolates from Yunnan and Anhui provinces of China

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background

          Plasmodium vivax is the predominant species of human malaria parasites present in China. Although sulphadoxine-pyrimethamine (SP) and chloroquine (CQ) have been widely used for malaria treatment in China, the resistance profiles of these drugs are not available. Analysis of dihydrofolate reductase ( dhfr), dihydropteroate synthase ( dhps), and multidrug resistance ( mdr-1) gene mutations in P. vivax isolates is a valuable molecular approach for mapping resistance to SP and CQ. This study investigates the prevalence of pvdhfr, pvdhps, and pvmdr-1 of P. vivax clinical isolates from China and provides baseline molecular epidemiologic data on SP- and CQ-associated resistance in P. vivax.

          Methods

          Plasmodium vivax clinical isolates were collected from two malaria-endemic regions of China, subtropical (Xishuangbanna, Yunnan province) and temperate (Bozhou, Anhui province), from 2009 to 2012. All isolates were analysed for single nucleotide polymorphism haplotypes in pvdhfr, pvdhps, and pvmdr-1 using direct DNA sequencing.

          Results

          In pvdhfr, 15% of Xishuangbanna isolates carried wild-type (WT) allele, whereas the majority of isolates carried mutant genes with substitutions at five codons. Eight mutant haplotypes of pvdhfr were detected, while limited polymorphism of pvdhfr was found in Bozhou isolates. A size polymorphism was present in pvdhfr, with the three-repeat type being the most predominate in both Xishuangbanna (79%) and Bozhou (97%) isolates. In pvdhps, mutations at four codons were detected in Xishuangbanna isolates leading to six haplotypes, including WT allele, single-mutation, double-mutation, and triple-mutation alleles. All Bozhou isolates carried WT pvhdps. In pvmdr-1, isolates from Xishuangbanna carried mutations at codons Y976F and F1076L, whereas all isolates from Bozhou had only a single mutation at codon F1076L.

          Conclusions

          Plasmodium vivax isolates from subtropical and temperate zones of China are shown to have dramatically different frequencies and patterns of mutations in pvdhfr, pvdhps, and pvmdr-1. Whereas P. vivax populations in subtropical China are highly resistant to SP and CQ, those in the temperate zone may still be susceptible to SP and CQ. This information is useful for establishing treatment policy and provides a baseline for molecular surveillance of drug-resistant P. vivax in these areas.

          Electronic supplementary material

          The online version of this article (doi:10.1186/1475-2875-13-346) contains supplementary material, which is available to authorized users.

          Related collections

          Most cited references50

          • Record: found
          • Abstract: found
          • Article: not found

          Mechanisms of resistance of malaria parasites to antifolates.

          Antifolate antimalarial drugs interfere with folate metabolism, a pathway essential to malaria parasite survival. This class of drugs includes effective causal prophylactic and therapeutic agents, some of which act synergistically when used in combination. Unfortunately, the antifolates have proven susceptible to resistance in the malaria parasite. Resistance is caused by point mutations in dihydrofolate reductase and dihydropteroate synthase, the two key enzymes in the folate biosynthetic pathway that are targeted by the antifolates. Resistance to these drugs arises relatively rapidly in response to drug pressure and is now common worldwide. Nevertheless, antifolate drugs remain first-line agents in several sub-Saharan African countries where chloroquine resistance is widespread, at least partially because they remain the only affordable, effective alternative. New antifolate combinations that are more effective against resistant parasites are being developed and in one case, recently introduced into use. Combining these antifolates with drugs that act on different targets in the parasite should greatly enhance their effectiveness as well as deter the development of resistance. Molecular epidemiological techniques for monitoring parasite drug resistance may contribute to development of strategies for prolonging the useful therapeutic life of this important class of drugs.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Identification of the Plasmodium vivax mdr-like gene (pvmdr1) and analysis of single-nucleotide polymorphisms among isolates from different areas of endemicity.

            Because of the lack of methods for continuous in vitro culture of Plasmodium vivax, little is known about drug-resistance mechanisms in this malaria-causing parasite. Therefore, identification of all the genes potentially involved in drug resistance and of molecular markers related to drug resistance would provide a framework for studying the incidence and spread of drug-resistant P. vivax strains. We have identified the P. vivax orthologue of the pfmdr1 gene (pvmdr1), which was shown to have a role in the drug resistance of Plasmodium falciparum. Comparison of the alignments of both nucleotide and amino acid sequences of pvmdr1 with those of other Plasmodium multidrug-resistance genes revealed an open-reading frame of 4392 base pairs encoding a deduced protein of 1464 amino acids. Nucleotide polymorphisms at 2 codons of the pvmdr1 gene--Y976F and F1076L--were found in 14 of 23 P. vivax isolates from different areas of endemicity, including Thailand, Indonesia, Turkey, Azerbaijan, and French Guyana.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Plasmodium vivax resistance to chloroquine in Madagascar: clinical efficacy and polymorphisms in pvmdr1 and pvcrt-o genes.

              No data were available concerning Plasmodium vivax resistance to chloroquine (CQ) in Madagascar. We investigated the therapeutic efficacy of CQ in P. vivax malaria, the prevalence of mutations in the pvcrt-o and pvmdr1 genes before treatment, and the association between mutant parasites and the clinical response of the patients to CQ treatment. Clinical isolates were collected at six sentinel sites located in the three epidemiological strata for malaria throughout Madagascar in 2006. Patients were enrolled, treated, and followed up according to the WHO 2001 guidelines for P. vivax infections. Sequencing was used to analyze polymorphisms of the pvcrt-o (exons 1 to 6) and pvmdr1 genes. The treatment failure rate, after adjustment for genotyping, was estimated at 5.1% for the 105 patients included, ranging from zero in the South to 14.8% in the foothills of the Central Highlands. All samples were wild type for pvcrt-o but mutant for the pvmdr1 gene. Ten nonsynonymous mutations were found in the pvmdr1 gene, including five new mutations, four of which were present at low frequencies (1.3% to 7.5%) while the S513R mutation was present at a much higher frequency (96.3%). The other five mutations, including Y976F, had been described before and had frequencies of 97.8% to 100%. Our findings suggest that CQ-resistant P. vivax isolates are present in Madagascar, particularly in the foothills of the Central Highlands. The 976Y pvmdr1 mutation was found not to be useful for monitoring CQ resistance. Further efforts are required to develop suitable tools for monitoring drug resistance in P. vivax malaria.
                Bookmark

                Author and article information

                Contributors
                huangbo198421@126.com
                thshg@126.com
                xsu@niaid.nih.gov
                893037020@qq.com
                768444919@qq.com
                bannacdcjfk@163.com
                fanglilu@yahoo.com
                Journal
                Malar J
                Malar. J
                Malaria Journal
                BioMed Central (London )
                1475-2875
                2 September 2014
                2 September 2014
                2014
                : 13
                : 1
                : 346
                Affiliations
                [ ]Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 Guangdong China
                [ ]Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080 Guangdong China
                [ ]School of Medicine, Jinan University, Guangzhou, 510632 Guangdong China
                [ ]Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892 USA
                [ ]State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361005 Fujian China
                [ ]Xishuangbanna CDC, Xishuangbanna Prefecture Jinghong, 666100 Yunnan China
                Article
                3378
                10.1186/1475-2875-13-346
                4161776
                25179752
                d60c71f9-dbb3-4a33-a97e-2b51e255b73b
                © Huang et al.; licensee BioMed Central Ltd. 2014

                This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

                History
                : 9 February 2014
                : 10 July 2014
                Categories
                Research
                Custom metadata
                © The Author(s) 2014

                Infectious disease & Microbiology
                plasmodium vivax,polymorphism,drug resistance markers,china
                Infectious disease & Microbiology
                plasmodium vivax, polymorphism, drug resistance markers, china

                Comments

                Comment on this article