Anti-pinworm activity of novel coumarin-based trisubstituted methanes in Syphacia obvelata-infected mice.

The control of pinworms mainly relies on use of anthelmintic drugs. At present, there exists only few medications against pinworms, and their repeated use pose a serious risk of resistance development. Therefore, new anti-pinworm drugs are required to overcome the risk of resistance. This study reports the anti-pinworm activity of three novel coumarin-based trisubstituted methanes (TRSMs), i.e., 6-Amino-5-((4-hydroxy-2-oxo-2H-chromen-3-yl)(4-fluoro-phenyl)methyl)-1,3-dimethyl-pyrimidine-2,4(1H,3H)-dione (1), 6-Amino-5-((4-hydroxy-2-oxo-2H-chromen-3-yl)(4-chlor-ophenyl)methyl)-1,3-dimethyl-pyrimidine-2,4(1H,3H)-dione (2) and 6-Amino-5-((4-hydroxy-2-oxo-2H-chromen-3-yl)(4-bromophenyl)methyl)-1,3-dimethyl-pyrimidine-2,4(1H,3H)-dione (3) in Syphacia obvelata-infected mice. The oral acute toxicity of compounds was examined using the OECD guidelines. The findings of this study reveal that TRSM analogues 1 and 2, at a single 80 mg/kg dose given for 5 days, can reduce about 90% of pinworm worm burden in mice, compared to 98% worm reduction shown by 20 mg/kg dose of albendazole, the reference drug, on the 12 day of infection. In particular, the fluoro-and bromo-substituents in the phenyl ring of synthesized derivatives greatly influence the efficacy of candidates. The oral acute toxicity of TRSMs was observed to be greater than 2000 mg/kg body weight for mice. Taken together, our study suggests that studied novel coumarin-based trisubstituted methanes could serve as suitable candidates for the development of new anti-pinworm drugs.

In vitro and in vivo anthelmintic study of Sesbania sesban var. bicolor, a traditionally used medicinal plant of Santhal tribe in Assam, India.

The leaf decoction of Sesbania sesban var. bicolor is used traditionally by Santhal tribe of Assam, India, for the treatment of intestinal helminthic infections. This study was conducted to evaluate the in vitro and in vivo anthelmintic efficacy of methanolic extract of S. sesban var. bicolor leaves using Hymenolepis diminuta-rat (cestode) and Syphacia obvelata-mice (nematode) as test parasites and models. Praziquantel (PZQ) and albendazole (ABZ) were used as reference drugs. At the highest concentration of 30 mg/ml of the plant extract, H. diminuta and S. obvelata showed mortality at 0.81 ± 0.01 h and 15.17 ± 0.05 h, respectively. The in vivo results substantiated the in vitro findings, and the extract showed a better cestocidal efficacy in a dose-dependent manner, whereby treatment of rats with 400 mg/kg of the plant extract caused 65.10% reduction in eggs per gram (EPG) of faeces and 56% reduction in worm counts. S. obvelata-infected mice treated at the same dose showed 34.32% and 47.08% reduction in EPG and worm counts at necropsy, respectively. The methanolic extract was subjected to bioassay-guided fractionation using different solvents and the ethyl acetate fraction proved to be the most active. This active fraction was subjected to column chromatography using varying concentrations of hexane:ethyl acetate. Maximum efficacy was observed in 7:3 hexane:ethyl acetate, where H. diminuta and S. obvelata showed mortality at 3.56 ± 0.12 h and 9.21 ± 0.02 h, respectively. This indicates that the isolated fraction contained the active component responsible for its anthelmintic activity, which substantiates the medicinal usage in traditional practice.

Effective eradication of pinworms (Syphacia obvelata and Aspiculuris tetraptera) with Polygonum cognatum Meissn.

Polygonum cognatum Meissn. (Polygonaceae) is a wild edible plant known locally as "solucanotu, madimak" in Turkey and it has been used for various purposes, such as diuretic and antidiabetic, as well to treat oxyuris and worms internally in humans. The present study was carried out to investigate the anthelmintic activity of various extracts were obtained from the aerial parts of P. cognatum in order to justify its traditional usage in Turkish folk medicine. n-Hexane, ethyl acetate and methanol extracts were prepared from the aerial parts of the plant, successively. The anthelmintic potentials of these extracts were evaluated on mice naturally infected with Syphacia obvelata and Aspiculuris tetraptera. Cellophane perianal tape test and fecal flotation test were used for the activity screening. The results were compared with control and reference groups. In addition to all these experiments, the total amount of phenolic compounds and tannin contents thought to be responsible for the activity were evaluated for all extracts. According to the results, it has been found that the methanolic extract reduced the number of S. obvelata (66.8%) and A. tetraptera (73.4%) eggs. Moreover, the methanolic extract include higher amount of total phenolic compound (48.75 ±â€¯0.82 mg of GA/g of extract) and tannin (30.04 ±â€¯0.22 mg TA/g of extract) than n-Hexane (17.21 ±â€¯0.75 mg of GA/g of extract; 6.82 ±â€¯0.41 mg TA/g of extract) and ethyl acetate (25.06 ±â€¯0.94 mg of GA/g of extract; 10.29 ±â€¯0.34 mg TA/g of extract); therefore the anthelmintic activity could be related to these constituents. The present study explored the anthelmintic potential of P. cognatum. Further studies should be conducted into the mechanism of these compounds' against helminths. This study can be an important step in the discovery of new anthelmintic agents.

Holobiont suture zones: Parasite evidence across the European house mouse hybrid zone.

Parasite hybrid zones resulting from host secondary contact have never been described in nature although parasite hybridization is well known and secondary contact should affect them similarly to free-living organisms. When host populations are isolated, diverge and recontact, intimate parasites (host specific, direct life cycle) carried during isolation will also meet and so may form parasite hybrid zones. If so, we hypothesize these should be narrower than the host's hybrid zone as shorter parasite generation time allows potentially higher divergence. We investigate multilocus genetics of two parasites across the European house mouse hybrid zone. We find each host taxon harbours its own parasite taxa. These also hybridize: Parasite hybrid zones are significantly narrower than the host's. Here, we show a host hybrid zone is a suture zone for a subset of its parasite community and highlight the potential of such systems as windows on the evolutionary processes of host-parasite interactions and recombinant pathogen emergence.

In vitro and in vivo anthelmintic efficacy of two pentacyclic triterpenoids, ursolic acid and betulinic acid against mice pinworm, Syphacia obvelata.

Pinworm infections are one of the common problems in laboratory rodents and man. At present there are only few drugs against intestinal helminths, and new drugs are urgently needed to cope up any future risk of drug resistance. Interest in plant secondary metabolites (PSMs) has risen considerably in the recent years for the discovery and development of new drugs. In the present study, we explored the in vitro and in vivo anthelmintic potentials of two pentacyclic triterpenoids, ursolic acid (UA) and betulinic acid (BA), the important PSMs of many medicinal plants, against Syphacia obvelata (Nematoda: Oxyuridae), a common pinworm of mice. The results of this study indicated that in both, in vitro and in vivo assays, BA showed comparatively better anthelmintic effects than UA. In the in vitro assay, 1.00 mg/ml concentration of BA showed paralysis and mortality of worms in 1.20 ± 0.04 and 2.30 ± 0.03 h, respectively. In the in vivo assay, a single 10.00 mg/kg dose of BA, administered for 5 days, revealed 68.78% reduction in egg counts and 84.08% reduction in worm counts of infected mice. The present study suggests that BA holds a great promise to be pursued further for detailed testing against some other representative group of helminth parasites.

Parasitic nematodes of the genus Syphacia Seurat, 1916 infecting Muridae in the British Isles, and the peculiar case of Syphacia frederici.

Syphacia stroma (von Linstow, 1884) Morgan, 1932 and Syphacia frederici Roman, 1945 are oxyurid nematodes that parasitize two murid rodents, Apodemus sylvaticus and Apodemus flavicollis, on the European mainland. Only S. stroma has been recorded previously in Apodemus spp. from the British Isles. Despite the paucity of earlier reports, we identified S. frederici in four disparate British sites, two in Nottinghamshire, one each in Berkshire and Anglesey, Wales. Identification was based on their site in the host (caecum and not small intestine), on key morphological criteria that differentiate this species from S. stroma (in particular the tail of female worms) and by sequencing two genetic loci (cytochrome C oxidase 1 gene and a section of ribosomal DNA). Sequences derived from both genetic loci of putative British S. frederici isolates formed a tight clade with sequences from continental worms known to be S. frederici, clearly distinguishing these isolates from S. stroma which formed a tight clade of its own, distinct from clades representative of Syphacia obvelata from Mus and S. muris from Rattus. The data in this paper therefore constitute the first record of S. frederici from British wood mice, and confirm the status of this species as distinct from both S. obvelata and S. stroma.

Syphacia obvelata: A New Hope to Induction of Intestinal Immunological Tolerance in C57BL/6 Mice.

The ability of nematodes to manipulate the immune system of their host towards a Th2 and T regulatory responses has been proposed to suppress the inflammatory response. Clinical trials have proposed a useful effect of helminth infections on improvement of inflammatory disorders. In this study, we investigated the immunomodulatory effect of Syphacia obvelata infection to induce intestinal tolerance in C57BL/6 mice. Mice were infected through the cagemates with self-infected BALB/c mice. Four weeks post-infection, expression levels of IFN-γ, TNF-α, IL-17, and IL-10 were assessed in the supernatant of mesenteric lymph node (MLN) culture. Foxp3+Treg were measured in MLN cells by flow cytometry. In the S. obvelata-infected group, the percentage of Tregs (5.2±0.4) was significantly higher than the control (3.6±0.5) (P<0.05). The levels of IL-10 (55.3±2.2 vs 35.2±3.2), IL-17 (52.9±3.8 vs 41±1.8), IFN-γ (44.8±4.8 vs 22.3±2.3) and TNF-α (71.1±5.8 vs 60.1±3.3) were significantly increased in infected mice compared to the control group (P<0.05). The above results showed the potential effects of S. obvelata to induce intestinal tolerance. Therefore, it seems that S. obvelata may increase the immunological suppressive function in the intestinal tract.

Syphacia obvelata: A New Hope to Induction of Intestinal Immunological Tolerance in C57BL/6 Mice

The ability of nematodes to manipulate the immune system of their host towards a Th2 and T regulatory responses has been proposed to suppress the inflammatory response. Clinical trials have proposed a useful effect of helminth infections on improvement of inflammatory disorders. In this study, we investigated the immunomodulatory effect of Syphacia obvelata infection to induce intestinal tolerance in C57BL/6 mice. Mice were infected through the cagemates with self-infected BALB/c mice. Four weeks post-infection, expression levels of IFN-γ, TNF-α, IL-17, and IL-10 were assessed in the supernatant of mesenteric lymph node (MLN) culture. Foxp3⁺Treg were measured in MLN cells by flow cytometry. In the S. obvelata-infected group, the percentage of Tregs (5.2±0.4) was significantly higher than the control (3.6±0.5) (P<0.05). The levels of IL-10 (55.3±2.2 vs 35.2±3.2), IL-17 (52.9±3.8 vs 41±1.8), IFN-γ (44.8±4.8 vs 22.3±2.3) and TNF-α (71.1±5.8 vs 60.1±3.3) were significantly increased in infected mice compared to the control group (P<0.05). The above results showed the potential effects of S. obvelata to induce intestinal tolerance. Therefore, it seems that S. obvelata may increase the immunological suppressive function in the intestinal tract.

In vitro and in vivo anthelmintic effects of Caesalpinia bonducella (L.) Roxb. leaf extract on Hymenolepis diminuta (Cestoda) and Syphacia obvelata (Nematoda).

BACKGROUND: Leaves of Caesalpinia bonducella (L.) Roxb. have been traditionally used as an herbal remedy to treat the intestinal helminthic infections in traditional medicine of India. AIM: This study was undertaken to evaluate the potential in vitro and in vivo anthelmintic effects of C. bonducella leaf extract against Syphacia obvelata (Nematoda) and Hymenolepis diminuta (Cestoda). MATERIALS AND METHODS: The in vitro anthelmintic activity of the extract was investigated on adult worms of S. obvelata (Nematoda) and H. diminuta (Cestoda) in terms of physical motility and mortality of parasites. The in vivo study was performed in H. diminuta-rat model and S. obvelata-mice model, by monitoring the egg per gram of feces count and worm count of animals following the treatment with different doses of plant extract. RESULTS: The study recorded significant and dose-dependent anthelmintic effects of the extract on both the parasites. In the in vitro study, 30 mg/ml concentration of extract caused mortality of H. diminuta in 2.5 ± 0.2 h and S. obvelata in 3.57 ± 0.16 h. In the in vivo study, the extract showed a comparatively better efficacy on S. obvelata, where its 800 mg/kg dose revealed 93% reduction of worm load in mice, as compared to 85% worm load reduction of H. diminuta in rats. CONCLUSIONS: The findings suggest that leaf extract of C. bonducella possesses significant anthelmintic effects and supports its use as an anthelmintic in traditional medicine. This appears to be the first report of in vivo anthelmintic activity of C. bonducella against these parasites.

Comparative analyses of the complete mitochondrial genomes of the two murine pinworms Aspiculuris tetraptera and Syphacia obvelata.

Pinworms Aspiculuris tetraptera and Syphacia obvelata are important parasitic nematodes of laboratory mice, rat and other rodents. However, the mitochondrial (mt) genome of these parasites have not been known yet. In the present study, the complete mt genomes of A. tetraptera and S. obvelata were sequenced, which were 13,669 bp and 14,235 bp in size, respectively. Both genomes included 12 protein-coding genes, two rRNA genes, 22 tRNA genes and one non-coding region. The mt genomes of A. tetraptera and S. obvelata preferred bases A and T, with the highest for T and the lowest for C. The mt gene arrangements of the two pinworms were the same as that of the GA8 type. Phylogenetic analysis using mtDNA data revealed that the Bayesian inference (BI) trees contained two big branches: species from Oxyuridomorpha, Rhabditomorpha and Ascaridomorpha formed one branch, and those from Spiruromorpha formed another branch with high statistical support. The two murine pinworms A. tetraptera and S. obvelata have closer relationship than to other pinworms. This study provides a foundation for studying the population genetics, systematics and molecular phylogeny of pinworms.

Intestinal nematodes from small mammals captured near the demilitarized zone, Gyeonggi province, Republic of Korea.

A total of 1,708 small mammals (1,617 rodents and 91 soricomorphs), including Apodemus agrarius (n = 1,400), Microtus fortis (167), Crocidura lasiura (91), Mus musculus (32), Myodes (= Eothenomys) regulus (9), Micromys minutus (6), and Tscherskia (= Cricetulus) triton (3), were live-trapped at US/Republic of Korea (ROK) military training sites near the demilitarized zone (DMZ) of Paju, Pocheon, and Yeoncheon, Gyeonggi Province from December 2004 to December 2009. Small mammals were examined for their intestinal nematodes by necropsy. A total of 1,617 rodents (100%) and 91 (100%) soricomorphs were infected with at least 1 nematode species, including Nippostrongylus brasiliensis, Heligmosomoides polygyrus, Syphacia obvelata, Heterakis spumosa, Protospirura muris, Capillaria spp., Trichuris muris, Rictularia affinis, and an unidentified species. N. brasiliensis was the most common species infecting small mammals (1,060; 62.1%) followed by H. polygyrus (617; 36.1%), S. obvelata (370; 21.7%), H. spumosa (314; 18.4%), P. muris (123; 7.2%), and Capillaria spp. (59; 3.5%). Low infection rates (0.1-0.8%) were observed for T. muris, R. affinis, and an unidentified species. The number of recovered worms was highest for N. brasiliensis (21,623 worms; mean 20.4 worms/infected specimen) followed by S. obvelata (9,235; 25.0 worms), H. polygyrus (4,122; 6.7 worms), and H. spumosa (1,160; 3.7 worms). A. agrarius demonstrated the highest prevalence for N. brasiliensis (70.9%), followed by M. minutus (50.0%), T. triton (33.3%), M. fortis (28.1%), M. musculus (15.6%), C. lasiura (13.2%), and M. regulus (0%). This is the first report of nematode infections in small mammals captured near the DMZ in ROK.

Genetic variability among Syphacia obvelata isolates from laboratory mice in four different geographical locations of China revealed by sequence analyses of five mitochondrial genes.

Syphacia obvelata is a rodent nematode with high prevalence in laboratory mice. In the present study, we examined the genetic variability of S. obvelata from naturally infected laboratory mice in four different provinces, China. Five mitochondrial (mt) DNA regions, namely cytochrome c oxidase subunit 1 (pcox1), cytochrome b (pcytb), large subunit ribosomal RNA (prrnL) and NADH dehydrogenase subunits 1 and 5 (pnad1 and pnad5), were amplified separately from individual nematodes by PCR, and then sequenced directly. The size of the sequences of pcox1, pcytb, prrnL, pnad1 and pnad5 was 628 bp, 555 bp, 548 bp, 548 bp and 561 bp, respectively. While the intra-specific sequence variations within S. obvelata were 0-1.0% for pcox1, 0-1.6% for pcytb, 0-2.8% for prrnL, 0-2.0% for pnad1 and 0-1.8% for pnad5, the inter-specific sequence differences among members of the Oxyuridae were significantly higher, being 14.0-17.5% for pcox1, 27.5-32.9% for pcytb, 35.8-37.2% for prrnL, 22.2-26.8% for pnad1 and 22.3-25.2% for pnad5, respectively. Phylogenetic analyses based on combined sequences of four mt protein-coding genes, using Bayesian inference (BI), maximum likelihood (ML) and maximum parsimony (MP) methods, indicated that all of the S. obvelata samples grouped together with high statistical support, but samples from the same geographical origin did not always cluster together. These findings demonstrated the existence of low-level intra-specific variation in five mtDNA sequences among S. obvelata isolates from laboratory mice, but no obvious geographical distinction among S. obvelata isolates from laboratory mice in different geographic regions in China. These results provide basic information for further studies of systematics and population genetics of S. obvelata.

Intestinal Nematodes from Small Mammals Captured near the Demilitarized Zone, Gyeonggi Province, Republic of Korea

A total of 1,708 small mammals (1,617 rodents and 91 soricomorphs), including Apodemus agrarius (n = 1,400), Microtus fortis (167), Crocidura lasiura (91), Mus musculus (32), Myodes (= Eothenomys) regulus (9), Micromys minutus (6), and Tscherskia (= Cricetulus) triton (3), were live-trapped at US/Republic of Korea (ROK) military training sites near the demilitarized zone (DMZ) of Paju, Pocheon, and Yeoncheon, Gyeonggi Province from December 2004 to December 2009. Small mammals were examined for their intestinal nematodes by necropsy. A total of 1,617 rodents (100%) and 91 (100%) soricomorphs were infected with at least 1 nematode species, including Nippostrongylus brasiliensis, Heligmosomoides polygyrus, Syphacia obvelata, Heterakis spumosa, Protospirura muris, Capillaria spp., Trichuris muris, Rictularia affinis, and an unidentified species. N. brasiliensis was the most common species infecting small mammals (1,060; 62.1%) followed by H. polygyrus (617; 36.1%), S. obvelata (370; 21.7%), H. spumosa (314; 18.4%), P. muris (123; 7.2%), and Capillaria spp. (59; 3.5%). Low infection rates (0.1-0.8%) were observed for T. muris, R. affinis, and an unidentified species. The number of recovered worms was highest for N. brasiliensis (21,623 worms; mean 20.4 worms/infected specimen) followed by S. obvelata (9,235; 25.0 worms), H. polygyrus (4,122; 6.7 worms), and H. spumosa (1,160; 3.7 worms). A. agrarius demonstrated the highest prevalence for N. brasiliensis (70.9%), followed by M. minutus (50.0%), T. triton (33.3%), M. fortis (28.1%), M. musculus (15.6%), C. lasiura (13.2%), and M. regulus (0%). This is the first report of nematode infections in small mammals captured near the DMZ in ROK.

Intestinal Nematodes from Small Mammals Captured near the Demilitarized Zone, Gyeonggi Province, Republic of Korea

A total of 1,708 small mammals (1,617 rodents and 91 soricomorphs), including Apodemus agrarius (n = 1,400), Microtus fortis (167), Crocidura lasiura (91), Mus musculus (32), Myodes (= Eothenomys) regulus (9), Micromys minutus (6), and Tscherskia (= Cricetulus) triton (3), were live-trapped at US/Republic of Korea (ROK) military training sites near the demilitarized zone (DMZ) of Paju, Pocheon, and Yeoncheon, Gyeonggi Province from December 2004 to December 2009. Small mammals were examined for their intestinal nematodes by necropsy. A total of 1,617 rodents (100%) and 91 (100%) soricomorphs were infected with at least 1 nematode species, including Nippostrongylus brasiliensis, Heligmosomoides polygyrus, Syphacia obvelata, Heterakis spumosa, Protospirura muris, Capillaria spp., Trichuris muris, Rictularia affinis, and an unidentified species. N. brasiliensis was the most common species infecting small mammals (1,060; 62.1%) followed by H. polygyrus (617; 36.1%), S. obvelata (370; 21.7%), H. spumosa (314; 18.4%), P. muris (123; 7.2%), and Capillaria spp. (59; 3.5%). Low infection rates (0.1-0.8%) were observed for T. muris, R. affinis, and an unidentified species. The number of recovered worms was highest for N. brasiliensis (21,623 worms; mean 20.4 worms/infected specimen) followed by S. obvelata (9,235; 25.0 worms), H. polygyrus (4,122; 6.7 worms), and H. spumosa (1,160; 3.7 worms). A. agrarius demonstrated the highest prevalence for N. brasiliensis (70.9%), followed by M. minutus (50.0%), T. triton (33.3%), M. fortis (28.1%), M. musculus (15.6%), C. lasiura (13.2%), and M. regulus (0%). This is the first report of nematode infections in small mammals captured near the DMZ in ROK.