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1.
Mol Biochem Parasitol ; 238: 111297, 2020 07.
Article in English | MEDLINE | ID: mdl-32619645

ABSTRACT

Like mammalian cells, helminth parasites are equipped with an array of enzymatic anti-oxidant system which has an adaptive strategy to cope up with several conditions of stress that arise from host immune response or drug treatment. Earlier, we had reported that three species of Senna, viz. S. alata, S. alexandrina and S. occidentalis leaf extracts caused severe morphological and biochemical alterations in the zoonotic parasite Hymenolepis diminuta. To understand whether the leaf extracts of the three species of Senna have any effect on the enzymatic anti-oxidant system in H.diminuta or not, the present study was investigated on the mechanism of action of these leaf extracts on the anti-oxidant system of the parasite. The viability of the parasite was assessed by MTT reduction assay, chromatin condensation through Hoechst staining of tissue and DNA fragmentation assay, and the oxidative enzymes of the parasite were estimated biochemically. Activity of superoxide dismutase, catalase, glutathione S- transferase and glutathione peroxidase were found to be increased in all the treated parasites from that of the control, with S. alata showed the highest increased amongst the three plant species in all the enzymes, at 331.0 %, 215.4 %, 85.4 % and 65.5 % respectively. Upliftment of apoptotic protein CED-3, CED-4 and EGL-1 and down regulation of anti-apototic protein CED-9 was visualised in all treated paraites. The redox imbalance triggered by these leaf extracts resulted in the activation of apoptotic pathway that led to death of the parasite. Our results demonstrated that the leaf extracts of the three Senna plant species could open new insight for an affordable natural anthelmintic with high efficacy and less toxicity.


Subject(s)
Anthelmintics/pharmacology , Apoptosis/drug effects , DNA, Helminth/genetics , Hymenolepis diminuta/drug effects , Reactive Oxygen Species/agonists , Senna Plant/chemistry , Animals , Anthelmintics/isolation & purification , Apoptosis/genetics , Caspases/genetics , Caspases/metabolism , Catalase/genetics , Catalase/metabolism , DNA Fragmentation/drug effects , DNA, Helminth/antagonists & inhibitors , DNA, Helminth/metabolism , Gene Expression Regulation/drug effects , Glutathione Peroxidase/genetics , Glutathione Peroxidase/metabolism , Glutathione Transferase/genetics , Glutathione Transferase/metabolism , Hymenolepis diminuta/genetics , Hymenolepis diminuta/growth & development , Hymenolepis diminuta/metabolism , Plant Extracts/chemistry , Plant Leaves/chemistry , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Protozoan Proteins/genetics , Protozoan Proteins/metabolism , Reactive Oxygen Species/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism
2.
Sci Data ; 6(1): 302, 2019 12 03.
Article in English | MEDLINE | ID: mdl-31796747

ABSTRACT

Despite the use of Hymenolepis diminuta as a model organism in experimental parasitology, a full genome description has not yet been published. Here we present a hybrid de novo genome assembly based on complementary sequencing technologies and methods. The combination of Illumina paired-end, Illumina mate-pair and Oxford Nanopore Technology reads greatly improved the assembly of the H. diminuta genome. Our results indicate that the hybrid sequencing approach is the method of choice for obtaining high-quality data. The final genome assembly is 177 Mbp with contig N50 size of 75 kbp and a scaffold N50 size of 2.3 Mbp. We obtained one of the most complete cestode genome assemblies and annotated 15,169 potential protein-coding genes. The obtained data may help explain cestode gene function and better clarify the evolution of its gene families, and thus the adaptive features evolved during millennia of co-evolution with their hosts.


Subject(s)
Genome, Helminth , Hymenolepis diminuta/genetics , Animals , Molecular Sequence Annotation , Sequence Analysis, DNA
3.
Korean J Parasitol ; 55(3): 351-355, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28719963

ABSTRACT

Hymenolepis nana and Hymenolepis diminuta are globally widespread zoonotic cestodes. Rodents are the main reservoir host of these cestodes. Brown rats (Rattus norvegicus) are the best known and most common rats, and usually live wherever humans live, especially in less than desirable hygiene conditions. Due to the little information of the 2 hymenolepidid species in brown rats in China, the aim of this study was to understand the prevalence and genetic characterization of H. nana and H. diminuta in brown rats in Heilongjiang Province, China. Total 114 fecal samples were collected from brown rats in Heilongjiang Province. All the samples were subjected to morphological examinations by microscopy and genetic analysis by PCR amplification of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene and the internal transcribed spacer 2 (ITS2) region of the nuclear ribosomal RNA gene. In total, 6.1% (7/114) and 14.9% (17/114) of samples were positive for H. nana and H. diminuta, respectively. Among them, 7 and 3 H. nana isolates were successfully amplified and sequenced at the COX1 and ITS2 loci, respectively. No nucleotide variations were found among H. nana isolates at either of the 2 loci. Seventeen H. diminuta isolates produced 2 different COX1 sequences while 7 ITS2 sequences obtained were identical to each other. The present results of H. nana and H. diminuta infections in brown rats implied the risk of zoonotic transmission of hymenolepiasis in China. These molecular data will be helpful to deeply study intra-specific variations within Hymenolepis cestodes in the future.


Subject(s)
Hymenolepis diminuta/isolation & purification , Hymenolepis nana/isolation & purification , Rats/parasitology , Animals , Base Sequence , China/epidemiology , Electron Transport Complex IV/genetics , Feces/parasitology , Humans , Hymenolepiasis/epidemiology , Hymenolepiasis/parasitology , Hymenolepiasis/transmission , Hymenolepis diminuta/genetics , Hymenolepis diminuta/ultrastructure , Hymenolepis nana/genetics , Hymenolepis nana/ultrastructure , Mitochondria/enzymology , Mitochondria/genetics , Polymerase Chain Reaction , Prevalence , RNA, Helminth/genetics , RNA, Ribosomal/genetics , Zoonoses/epidemiology , Zoonoses/parasitology
4.
Parasitol Res ; 115(11): 4293-4298, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27473838

ABSTRACT

Given the widespread distribution and medical implication of members of the genus Hymenolepis, specific identification of the aetiological agent becomes imperative. For precise diagnosis of the species, molecular techniques such as PCR and RFLP of the nuclear ribosomal internal transcribed spacer 2 (rDNA-ITS2) gene marker were carried out. The results showed distinct restriction patterns for both Hymenolepis nana and Hymenolepis diminuta when digested with either of the enzymes RsaI, HaeIII or HhaI. The annotated rDNA-ITS2 sequences from the two species revealed differences in the length; the folded secondary structure also depicted clear demarcation between the two species with variations in length of the helices, pyrimidine-pyrimidine mismatches and sites where motifs occur. In phylogenetic analysis of the evolutionary relationship between the two species as well as with other members of the family Hymenolepididae, the species causing human hymenolepiasis were found to be distantly related as they diverged independently from the ancestral lineage.


Subject(s)
DNA, Ribosomal Spacer/genetics , Hymenolepiasis/diagnosis , Hymenolepis diminuta/genetics , Hymenolepis nana/genetics , Animals , Diagnosis, Differential , Genetic Markers/genetics , Humans , Hymenolepiasis/parasitology , Phylogeny , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Rats
5.
Parasitol Res ; 115(3): 1253-62, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26666886

ABSTRACT

Hymenolepis nana, commonly known as the dwarf tapeworm, is one of the most common tapeworms of humans and rodents and can cause hymenolepiasis. Although this zoonotic tapeworm is of socio-economic significance in many countries of the world, its genetics, systematics, epidemiology, and biology are poorly understood. In the present study, we sequenced and characterized the complete mitochondrial (mt) genome of H. nana. The mt genome is 13,764 bp in size and encodes 36 genes, including 12 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNA genes. All genes are transcribed in the same direction. The gene order and genome content are completely identical with their congener Hymenolepis diminuta. Phylogenetic analyses based on concatenated amino acid sequences of 12 protein-coding genes by Bayesian inference, Maximum likelihood, and Maximum parsimony showed the division of class Cestoda into two orders, supported the monophylies of both the orders Cyclophyllidea and Pseudophyllidea. Analyses of mt genome sequences also support the monophylies of the three families Taeniidae, Hymenolepididae, and Diphyllobothriidae. This novel mt genome provides a useful genetic marker for studying the molecular epidemiology, systematics, and population genetics of the dwarf tapeworm and should have implications for the diagnosis, prevention, and control of hymenolepiasis in humans.


Subject(s)
Genome, Mitochondrial , Hymenolepiasis/parasitology , Hymenolepis nana/genetics , Zoonoses/parasitology , Amino Acid Sequence , Animals , Base Sequence , Bayes Theorem , Cestoda/classification , Cestoda/genetics , DNA, Mitochondrial/chemistry , DNA, Mitochondrial/genetics , Gene Order , Genetic Markers , Genome, Mitochondrial/genetics , Humans , Hymenolepiasis/transmission , Hymenolepis diminuta/classification , Hymenolepis diminuta/genetics , Hymenolepis nana/classification , Phylogeny , RNA, Ribosomal/chemistry , RNA, Ribosomal/genetics , RNA, Transfer/genetics
6.
Exp Parasitol ; 145: 61-7, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25092440

ABSTRACT

Toll-like receptors (TLRs) play a fundamental role in the rapid activation of innate immune responses to a variety of pathogen-associated molecular patterns (PAMPs). In a previous study we observed an increase in the level of expression of TLR2 and TLR4 mRNA in the jejunum and colon during experimental hymenolepidosis in rats. In this study, we performed a quantitative real-time polymerase chain reaction (qRT-PCR), Western blot analysis and immunohistochemical staining of TLR3 and TLR9 receptors during experimental hymenolepidosis in rats. The levels of mRNA and protein expression of TLR3 and TLR9 in the jejunum had increased at 16 days post Hymenolepis diminuta infection (dpi) in the case of TLR3 and at 16 and 25 dpi in the case of TLR9. In the colon the expression of TLR3 and TLR9 had increased at 16, 25 and 40 dpi. The results of the immunohistochemical reactions showed that H. diminuta infected rats (16, 25, 40 and 60 dpi) exhibited changes in TLR3 and TLR9 localization and intensity in the epithelial cells of the jejunum and colon. The changes in the level of TLR3 and TLR9 expression may confirm involvement of the innate immune system in the pathomechanism of hymenolepidosis.


Subject(s)
Hymenolepiasis/metabolism , Hymenolepis diminuta/genetics , Toll-Like Receptors/genetics , Animals , Blotting, Western , Gene Expression Regulation , Hymenolepis diminuta/metabolism , Immunohistochemistry , Intestine, Large/metabolism , Intestine, Large/parasitology , Intestine, Small/metabolism , Intestine, Small/parasitology , Male , RNA, Messenger/isolation & purification , Rats , Rats, Wistar , Real-Time Polymerase Chain Reaction , Toll-Like Receptor 3/genetics , Toll-Like Receptor 3/metabolism , Toll-Like Receptor 9/genetics , Toll-Like Receptor 9/metabolism , Toll-Like Receptors/metabolism
7.
Exp Parasitol ; 130(3): 261-6, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22209940

ABSTRACT

Toll receptors play a critical role in the rapid activation of innate immune responses to a variety of pathogens. In mammals, Toll-like receptors (TLR) have been found in both immune related cells and other cells. At present little is known about the participation of TLR in host defense mechanisms during parasitic infections. The aim of this study was to determine the expression of TLR2 and TLR4 genes in rat intestines during experimental hymenolepidosis. There is difference in expression of TLR2 and TLR4 genes in the colon and jejunum in uninfected rats: in the colon, mRNA of the examined TLR is present in much higher amounts than the jejunum, while the protein of the TLR also had a segmented specific distribution. In the jejunum isolated rats infected with Hymeolepis diminuta 6 and 8 days post infection (dpi), mRNA for TLR4 and TLR2 were significantly more strongly expressed in comparison with the uninfected controls. In the colon, a statistically significantly increased expression of TLR4 gene was observed only at 6 dpi, and at 8 dpi for the TLR2 gene. Moreover, we observed that during inflammation, the immunopositive cell number and the intensity of immunohistochemical staining (indicating the presence of TLR within intestinal epithelial cells), increased together with the duration of the infection period.


Subject(s)
Colon/metabolism , Hymenolepiasis/metabolism , Hymenolepis diminuta/genetics , Jejunum/metabolism , Toll-Like Receptor 2/genetics , Toll-Like Receptor 4/genetics , Animals , Colon/parasitology , Gene Expression , Hymenolepiasis/genetics , Hymenolepis diminuta/metabolism , Immunohistochemistry , Jejunum/parasitology , Male , RNA, Messenger/metabolism , Rats , Rats, Wistar , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/metabolism , Tribolium , Up-Regulation
8.
Genetics ; 169(4): 2127-35, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15687267

ABSTRACT

Information on the molecular basis of resistance and the evolution of resistance is crucial to an understanding of the appearance, spread, and distribution of resistance genes and of the mechanisms of host adaptation in natural populations. One potential important genetic constraint for the evolution of resistance is fitness cost associated with resistance. To determine whether host resistance to parasite infection is associated with fitness costs, we conducted simultaneous quantitative trait loci (QTL) mapping of resistance to parasite infection and fitness traits using the red flour beetle (Tribolium castaneum) and the tapeworm parasite (Hymenolepis diminuta) system in two independent segregating populations. A genome-wide QTL scan using amplified fragment length polymorphism (AFLP) markers revealed three QTL for beetle resistance to tapeworm infection. These three QTL account for 44-58% variance in beetle infection intensity. We identified five QTL for fecundity and five QTL for egg-to-adult viability, which accounted for 36-57% and 36-49%, respectively, of the phenotypic variance in fecundity and egg-to-adult viability. The three QTL conferring resistance were colocalized with the QTL affecting beetle fitness. The genome regions that contain the QTL for parasite resistance explained the majority of the variance in fecundity and egg-to-adult viability in the mapping populations. Colocalization of QTL conferring resistance to parasite infection and beetle fitness may result from the pleiotropic effects of the resistance genes on host fitness or from tight linkages between resistance genes and adverse deleterious mutations. Therefore, our results provide evidence that the genome regions conferring resistance to tapeworm infection are partially responsible for fitness costs in the resistant beetle populations.


Subject(s)
Chromosome Mapping/methods , Coleoptera/parasitology , Hymenolepis diminuta/genetics , Hymenolepis diminuta/pathogenicity , Immunity, Innate/genetics , Quantitative Trait Loci , Animals , Genetic Markers , Genome , Genotype , Linkage Disequilibrium , Models, Genetic , Models, Statistical , Phenotype , Polymorphism, Restriction Fragment Length
9.
Wiad Parazytol ; 48(1): 79-85, 2002.
Article in Polish | MEDLINE | ID: mdl-16883706

ABSTRACT

A continuation of a single-individual culture of Hymenolepis diminuta WMS ill from generations 37 to 66 revealed a very high infective ability of cysticercoids which is reflected in the percentage of tapeworms detected in relation to the number of cysticercoids given to rats (94.4%). The tapeworms investigated revealed a significant increase in the abundance of type 0p3a proglottids (those with no testes on the poral side and 3 on the aporal) in tapeworms of successive generation groups. Each group of tapeworms analysed statistically belonged to three successive generations and numbered 31-34 individuals. The mean abundances of 0p3a type proglottids in tapeworms of the first groups studied in experiment, including generations 37-39 and 40-42 were 9.2% and 9.5%, respectively. The last studied groups, including generations 61-63 and 64-66 had higher mean numbers of type 0p3a proglottids, at 11.1% and 11.5%, respectively. The quantitative figures of 1p3a type proglottids amounted to 1.6% and 1.3% in first generation groups and in the last two groups 0.8% and 1.0%, respectively. The probable cause of this significant (P < 0.01) relative increase in the numbers of 0p3a type proglottids and decrease (P < 0.01) in the numbers of 1p3a type proglottids was the deliberate selection of maternal tapeworms characterized by numbers of 0p3a type proglottids greater and 1p3a type proglottids smaller than the average for their generation.


Subject(s)
Hymenolepis diminuta/anatomy & histology , Hymenolepis diminuta/physiology , Inbreeding , Ovary/anatomy & histology , Testis/anatomy & histology , Animals , Female , Host-Parasite Interactions , Hymenolepis diminuta/genetics , Male , Phenotype , Rats , Selection, Genetic , Species Specificity
10.
Wiad Parazytol ; 47(1): 127-35, 2001.
Article in Polish | MEDLINE | ID: mdl-16888963

ABSTRACT

An average of 4.9 tapeworms were discovered on day 7 of a low-abundance H. diminuta infection of rats of race WAG alb. After 11 months, the mean was only relatively slightly lower at 3.6. These means represent 97.1 and 71.4% of the 5 cysticercoids supplied. In turn, 7 days and 11 months after rats were supplied with 110 cysticercoids, the respective percent-ages were 85.1 and 56.0. All 7- and 12-day tapeworms from the low-abundance and crowded infrapopulations were characterized by the presence of a terminal proglottid of lingulate shape, in which the excretory canals joined. In contrast, older (48-day and 11-month-old) worms showed typical apolysis of gravid proglottids. There were no reports of the destrobilation of tapeworms, and the relatively large number of tapeworms persisting 11 months into the infection is particularly noteworthy. The results point to the lack of any rapid rejection of tapeworms of the kind characterized in many other studies on H. diminuta.


Subject(s)
Genitalia/anatomy & histology , Hymenolepiasis/parasitology , Hymenolepis diminuta/anatomy & histology , Hymenolepis diminuta/genetics , Animals , Host-Parasite Interactions , Inbreeding , Rats , Species Specificity
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