Molecular characterization of Hymenolepis nana based on nuclear rDNA ITS2 gene marker

Molecular identification of the rodent-borne pathogen Rodentolepis nana using the genetic markers of ITS-1, 18 S, and 28 S rDNA

BACKGROUND

Rodentolepis nana (syn. Hymenolepis nana), the most common cyclophyllid tapeworm infecting rodents, is a well-studied gastrointestinal parasite in mice and belongs to the family Hymenolepididae.

METHODS

The present study focuses on the molecular analysis for the nuclear genes (ITS-1, 18 S, and 28 S rDNA) used for the accurate recognition of the recovered Rodentolepis species.

RESULTS

The annotated partial ITS-1, 18 S, and 28 S rDNA gene regions were deposited in GenBank (gbǀ MW310394.1, gbǀ MW327585.1, and gbǀ MW324479.1, respectively) and further used in the maximum likelihood method (ML) to clarify their genetic relationships at the species level. The interrogation sequence of R. nana was aligned and belonged to the family Hymenolepididae, in the same group as all Hymenolepis species, which were distinct from Cyclophyllidea cestodes, especially species belonging to Anoplocephalidae and Taeniidae. Sequence data support the paraphyly of Hymenolepis species.

CONCLUSIONS

The phylogeny supports the availability of the ITS-1, 18 S, and 28 S rDNA genes as reliable genetic markers for evolutionary relationships.

Diversity of parasites in two captive chimpanzee populations in southern Gabon

Captive chimpanzees living in confined environments like sanctuaries or primatology centers are frequently affected by gastrointestinal parasites. Some of these are likely to be transmitted to humans and may seriously affect public health. However little information is currently available on the gastrointestinal parasites of primates living in such environments. Here, we characterize the diversity and prevalence of gastrointestinal parasites in two populations of captive chimpanzees living in south-eastern Gabon. Our study reveals that at least nine parasite species infect the chimpanzees with high prevalence, including several helminths (Ascaris spp., Enterobius spp., Strongyloides spp., Trichuris spp., Hymenolepis spp., Mammomonogamus spp), three protozoa (Balantioides spp., Entamoeba spp. and Troglodytella spp) and several unidentified parasites. All the parasite taxa we identified had previously been identified in other primates, including humans. Age, sex and site type may influence infection rates and/or parasite diversity found in a particular host.

Novel Linezolid analogues with antiparasitic activity against Hymenolepis nana

The stereoselective synthesis and anti- Hymenolepis nana activity of six Linezolid-type compounds, obtained by chemical modification of l-Alanine, are reported in this work. The synthetic strategy was to prepare diasteromeric N,N-dibenzylamino oxazolidinones 1 and 2, and coupling with 4-(4-bromophenyl)morpholine (3) to obtain N,N-dibenzylamino Linezolid analogues 4 and 5. A hydrogenolysis reaction over 4 and 5 resulted in amino-free Linezolid analogues 6 and 7, which were acetylated to reach diasteromeric Linezolid analogues 8 and 9. The six Linezolid analogues 4-9 show in vitro antiparasitic activity against Hymenolepis nana cestode, but not against several bacterial strains. Interestingly, compounds 6, 7 and 9 exhibit high potency, having shorter paralysis and death times after exposure (6-10 and 18-21 min, respectively), shorter than those found with antihelmintic compound Praziquantel (20 and 30 min) at 20 mg/mL. In addition, a cytocompatibility assay of 6-9 with human cells (ARPE-19 cells) demonstrate a non-cytotoxic effect at 0.4 mM. These results show the pharmacological potential of the newly reported Linezolid-type analogues as antiparasitic agents against Hymenolepis nana.

Molecular genotypes analysis of Cryptosporidium and Hymenolepis in rats on Lombok Island, Indonesia

Background and Aim: Cryptosporidium parvum and Hymenolepis nana are intestinal parasites that are commonly found in the unclean environment. Their presence in rats promotes the transmission of the cryptosporidiosis and hymenolepiasis to humans or animals nearby. This study aimed to determine the molecular characteristics of C. parvum and H. nana and their distribution in rats on Lombok Island. Materials and Methods: C. parvum and H. nana were investigated in 50 rats from Lombok Island. The molecular-parasitological technique used was polymerase chain reaction and sequencing method. Results: From 50 samples of rats' stool from 10 locations on Lombok Island, 8% (4/50) of C. parvum was detected molecularly with an 18S rRNA gene and 2% (1/50) of H. nana with COX 1 gene. Phylogenetic analysis indicated that C. parvum carrying rats on Lombok Island have a genetic relationship with C. parvum with Obi7 isolates, Japan and H. nana has a genetic relationship with Rodentolepis nana identified with Hn-VT isolates, India. Conclusion: The highest incidence of parasites was found in rats that were caught in the urban areas of Lombok Island, West Nusa Tenggara, Indonesia. Immediately, public health programs in these types of contaminated areas should receive priority attention to prevent further transmission of the parasites from animals to human beings.