Total Worm Research Articles

In vitro and in vivo evaluation of cnicin from blessed thistle (Centaurea benedicta) and its inclusion complexes with cyclodextrins against Schistosoma mansoni.

Schistosomiasis, caused by a blood fluke of the genus Schistosoma, afflicts over 230 million people worldwide. Treatment of the disease relies on just one drug, praziquantel. Cnicin (Cn) is the sesquiterpene lactone found in blessed thistle (Centaurea benedicta) that showed antiparasitic activities but has not been evaluated against Schistosoma. However, cnicin has poor water solubility, which may limit its antiparasitic activities. To overcome these restrictions, inclusion complexes with cyclodextrins may be used. In this work, we evaluated the in vitro and in vivo antischistosomal activities of cnicin and its complexes with β-cyclodextrin (βCD) and 2-hydroxypropyl-β-cyclodextrin (HPβCD) against Schistosoma mansoni. Cnicin were isolated from C. benedicta by chromatographic fractionation. Complexes formed by cnicin and βCD (Cn/βCD), as well as by cnicin and HPβCD (Cn/HPβCD), were prepared by coprecipitation and characterized. In vitro schistosomicidal assays were used to evaluate the effects of cnicin and its complexes on adult schistosomes, while the in vivo antischistosomal assays were evaluated by oral and intraperitoneal routes. Results showed that cnicin caused mortality and tegumental alterations in adult schistosomes in vitro, also showing in vivo efficacy after intraperitoneal administration. The oral treatment with cnicin or Cn/βCD showed no significant worm reductions in a mouse model of schistosomiasis. In contrast, Cn/HPβCD complex, when orally or intraperitoneally administered to S. mansoni-infected mice, decreased the total worm load, and markedly reduced the number of eggs, showing high in vivo antischistosomal effectiveness. Permeability studies, using Nile red, indicated that HPβCD complex may reach the tegument of adult schistosomes in vivo. These results demonstrated the antischistosomal potential of cnicin in preparations with HPβCD.

Effect of birdsfoot trefoil cultivars on exsheathment of Haemonchus contortus in fistulated sheep

Proanthocyanidin (PAC, condensed tannin) containing forages have well-documented anti-parasitic effects against gastrointestinal nematodes (GIN) of small ruminants. Although extensive research has been conducted on the inhibition of exsheathment of the L3 stage of Haemonchus contortus by in vitro exposure to the extracts of PAC containing plants, only one study has previously attempted to replicate this process in vivo and it was found that consumption of fresh sainfoin slowed the exsheathment rate. No similar studies have explored the effect of feeding condensed tannin forages in the form of hay on in vivo exsheathment of GIN. Another PAC containing forage, birdsfoot trefoil (Lotus corniculatus, BFT), has a large area of adaptation globally and feeding BFT has been shown to reduce fecal egg counts and total worm burdens. However, its effect on the in vivo exsheathment of H. contortus in the rumen is unknown. Recent work from this laboratory showed that BFT populations differ in the ability of aqueous extracts of freeze-dried plants to reduce exsheathment of H. contortus in vitro, and that the reduced exsheathment caused by BFT populations did not directly correlate with PAC content. Therefore, the objective of this study was twofold: 1) to evaluate the ability of birdsfoot trefoil hay to impair ruminal exsheathment of H. contortus in vivo and 2) to measure the difference in exsheathment between three commercially available cultivars of birdsfoot trefoil representing a broad range of in vitro efficacy against H. contortus. Four rumen fistulated ewes were fed three cultivars of birdsfoot trefoil (cv. Bruce, Empire, and Pardee) hay or a control hay (alfalfa/grass hay) in a Latin 4 × 4 design. The effect of consumption of birdsfoot trefoil on the exsheathment of H. contortus larvae in vivo was evaluated. For each exsheathment test, two capsules with 2000 ensheathed third-stage larvae per capsule were placed in the rumen of each ewe for eight hours. Larval containment capsules were made by capping each end of a short piece of Tygon® tubing (ID 9.5 mm, OD 14.3 mm) with an 8 μm NuncTM Cell Culture Insert. Larval exsheathment and motility were examined pre and post rumen exposure. Three exsheathment tests were run per diet cycle. Consumption of BFT hay did not significantly alter larval exsheathment. These results highlight the importance of further in vivo testing on the role of condensed tannins and other plant secondary compounds on larval exsheathment in the rumen.

Individual variability among autochthonous sheep in Northern Tunisia to infection by abomasum nematodes and Babesia/Theileria parasites

In Tunisia, livestock plays an important role in the economy; unfortunately, Tunisian sheep population faces several health challenges. The aim of this trial was to study phenotypic variability of four local sheep breeds and strains to abomasum nematodes infection and to Babesia/Theileria parasites. Faeces, blood and abomasum contents were collected from 310 sheep slaughtered in eight commercial slaughterhouses across North Tunisia. Haematological and biochemical parameters were assessed. DNA was extracted and catch‐all primers were used to detect both Theileria spp. and Babesia spp. DNA. Faecal egg counts (FEC) was quantitatively assessed using simple flotation technique followed by McMaster technique. Male and female worms were collected from all abomasum contents and counted under a stereomicroscope. The percentage of faeces samples positive for GIN’s eggs was 30.82%. After worms’ recovery, the infection prevalence was estimated to 75.90%. The overall infection prevalence by Babesia spp. and Theileria spp. was 4.21%. The dispersion of observations plots obtained by principal component analysis (PCA) showed two clusters of individuals. The first cluster contains animals having positive Babesia/Theileria PCR, presence of nematodes in the abomasum contents and relatively low total worm count (TWC < 500) expect one animal which was found bearing high TWC (>500). In this same group, with a suspected form of resistance, animals showed normal values of albumin and normal haematological parameters (red blood cell count [RBC], haemoglobin [Hb] and packed cell volume [PCV]). The second cluster represents all the other observations in which subgroups of animals were distinguished on the basis of their potential resistance to abomasum nematodes. Multiple correlations showed significant positive correlations between RBC/Hb, RBC/PCV, PCV/Hb and FEC/TWC. Significant negative correlations were observed between TWC/RBC and TWC/Hb. It is concluded that the phenotypic variability among local sheep breeds is essential for more advanced genetic and genomic studies.

In vivo studies of the effect of PPQ-6, a quinoline-based agent against Schistosoma mansoni in mice

Schistosomiasis is still a public health problem. Praziquantel is the only drug available for treatment of all forms of human schistosomiasis. Although praziquantel is an effective drug against all species of human schistosomes, concerns about resistance have been raised, especially in endemic areas. A hybrid compound containing several pharmacophore within a single molecule is a promising strategy. Here, we described the anti-schistosomal effect of 4-(2-Chloroquinolin-3-yl)-2-oxo-6-(p-tolyl)-1,2-dihydropyridine-3-carbonitrile (PPQ-6), a hybrid drug based on quinoline and pyridine. PPQ-6 was given as two regimens (20 or 40 mg/kg). In both regimens, PPQ-6 significantly reduced liver and spleen indices, nitric oxide production, tissue egg load, hepatic granuloma size and count, immature eggs and total worm burden especially females. Our findings suggested that PPQ-6 is a promising anti-schistosomal agent; however more research is needed to elucidate its mechanism of action and report its activity on juvenile schistosomes and other species of human schistosomes.

Effect of N-Fixing Bacteria and Variable Organic Matter on Some Characteristics of Vermicompost

Abstract—The aim of this study was investigated the effect of N-fixing and variable organic matter on some of the chemical properties of vermicompost. Treatments included factorial of nitrogen-fixing bacteria in four levels (no inoculation with bacteria, inoculate with Azotobacter, commercial Nitroxin and commercial Nitrokara), and the effects of various substrates in three levels (cow manure, straw and plantain leaf in ratio of 50:50). Measurements were the traits of the weight of produced worm biomass, the amount of cocoon production, total carbon and total nitrogen. Result showed that the heaviest adult worm weight, total worms and cocoon weight was observed in cow manure treatment that has not been inoculated. Treatment of cow manure with plantain leaf in ratio of 50 : 50 and Azotobacter, had the highest percentage of organic materials among the treatments and the maximum amount of total nitrogen obtained from treatment containing cow manure 50% + plantain leaf 50% and Azotobacter. Free-living aerobic bacteria, by using supplemented energy, improved the quality of final vermicompost but had no effect on the weight of biomass.

EVALUATION OF PLUMBAGIN AS A POTENTIAL THERAPEUTIC AGENT FOR MURINE SCHISTOSOMIASIS MANSONI

Schistosomiasis still one of the major health problems worldwide, affecting millions of people in economically challenged tropical and subtropical countries of the world. Currently the treatment of schistosomiasis relies on a single anti-parasitic drug praziquantel; however it was found it is not fully effective and the potential for development of resistant to praziquantel has justified the research for new alternative chemotherapies especially from natural sources. The current study evaluated the anti-parasitic effect of plumbagin against S. mansoni infected mice either alone or in combination with praziquantel through, parasitological parameters (worm load, oogram pattern, liver and intestine egg load) and histopathological parameters (granuloma number and diameter). Plumbagin showed a significant reduction in total worm burden (P <0.05), increase in dead eggs in oogram pattern and reduction in tissue ova count. Mean hepatic granulomas number and diameter were decreased with elevation in percentage of degenerated ova, compared to control group. Results were improved when praziquantel was used in combination with plumbagin as no male or coupled worm were detected, no immature ova and highly significant reduction in tissue egg load in liver and intestine (P < 0.001) compared to infected control group.

EVALUATION OF PLUMBAGIN AS A POTENTIAL THERAPEUTIC AGENT FOR MURINE SCHISTOSOMIASIS MANSONI

Schistosomiasis still one of the major health problems worldwide, affecting millions of people in economically challenged tropical and subtropical countries of the world. Currently the treatment of schistosomiasis relies on a single anti-parasitic drug praziquantel; however it was found it is not fully effective and the potential for development of resistant to praziquantel has justified the research for new alternative chemotherapies especially from natural sources. The current study evaluated the anti-parasitic effect of plumbagin against S. mansoni infected mice either alone or in combination with praziquantel through, parasitological parameters (worm load, oogram pattern, liver and intestine egg load) and histopathological parameters (granuloma number and diameter). Plumbagin showed a significant reduction in total worm burden (P <0.05), increase in dead eggs in oogram pattern and reduction in tissue ova count. Mean hepatic granulomas number and diameter were decreased with elevation in percentage of degenerated ova, compared to control group. Results were improved when praziquantel was used in combination with plumbagin as no male or coupled worm were detected, no immature ova and highly significant reduction in tissue egg load in liver and intestine (P < 0.001) compared to infected control group.

Praziquantel - chitosan nanoformulation against murine Schistosoma mansoni infection

Abstract The aim of the present work was to design praziquantel (PZQ) loaded chitosan nanoparticles (PZQ-Cs) to improve the oral bioavailability and overcome the drawbacks of conventional PZQ therapy. The synthesized chitosan nanoparticles (CsNPs) were physico-chemically characterized by TEM and dynamic light scattering (DLS) with the calculation of the encapsulation efficiency (EE). PZQ was loaded into CsNPs in three different doses; reduced dose (250 mg/kg), high dose (500 mg/kg) and fully effective dose (1000 mg/ kg). Infected treated groups received either oral PZQ-Cs or oral PZQ alone 42 days post-infection and were sacrificed 2 weeks post-treatment. The current study revealed that PZQ-Cs induced a significant anti-schistosomal effect, compared to the infected non-treated control. However, on comparison with conventional PZQ treatment at the corresponding doses, oral PZQ-Cs showed a lower anti-schistosomal potential as reflected by the total worm burden, tissue ova count and oogram pattern. PZQ-Cs was significantly effective in attenuating the oxidative insult associated with S. mansoni infection, compared to the infected non-treated and PZQ treated groups. Genotoxicity assessment proved the safety of CsNPs, as they did not induce a significant DNA fragmentation in non-infected mice treated with blank CsNPs. The present work highlights CsNPs as safe, effective anti-inflammatory and antioxidant agents that could find a clinical use in the treatment of schistosomiasis induced oxidative stress and hepatic dysfunction. Further studies are recommended, however, to investigate how PZQ-Cs could be further modified to increase its anti-schistosomal potential.

Efficacy and antiparasitic mechanism of curdione from Curcuma zedoaria against Gyrodactylus kobayashii in goldfish

Monogeneans are principally ectoparasites of fish with a global distribution and result in fish morbidity and mortality in aquaculture. Since current treatments mainly rely on the application of toxic or unapproved chemicals, there is an urgent need to identify new anthelmintic agents. In the present study, in vivo anthelminthic activities of 33 selected medicinal plants were investigated against Gyrodactylus kobayashii, a monogenean parasite infecting goldfish (Carassius auratus). The screening results showed that the methanol extracts of Curcuma zedoaria and Peucedanum praeruptorum had the highest activity against G. kobayashii. The concentration required to kill all parasites of two extracts was both 30 mg/L within 48 h of exposure, while C. zedoaria methanol extract showed lower toxicity to goldfish and was selected for the next study. Subsequently, two major sesquiterpene compounds from C. zedoaria, curdione and curcumenol were further tested for anthelminthic efficacy. The results revealed that only curdione demonstrated in vitro and in vivo antiparasitic effects, 12 mg/L killed 87.04% of G. kobayashii after 2 h in in vitro trials. And bathing G. kobayashii-infected goldfish in curdione induced significant reduction in a total worm burden, with EC50 values of 1.323 and 0.885 mg/L after 24 and 48-h immersion, respectively, and 100% efficacy was achieved at a concentration of 4.0 mg/L after 48 h. Furthermore, to gain insight into the plausible mechanism of anthelminthic activity of curdione, its effects on the ultrastructural alterations of G. kobayashii were performed in vivo by SEM which displayed obvious tegumental damages. Further confirmation of the significant declines of ATP contents in worms were obtained after both in vitro and in vivo treatments with curdione. These findings indicated that curdione mediated worm killing was associated with tegumental damages and energy insufficient. The results suggested that curdione has the potential as an alternative natural compound for the control of Gyrodactylus infections.

Typhlitis Associated With Natural Trichuris sp. Infection in Cats.

Trichuris spp. infections can cause typhlitis or typhlocolitis in many species, but there are no published studies about its pathology in cats. Trichuris sp. infection in cats appears to be rare in most parts of the world but is frequent in some tropical and subtropical regions. The purpose of this study was to describe intestinal lesions associated with natural Trichuris sp. infections in cats of St. Kitts, West Indies. Comprehensive autopsies, histopathological assessment of small and large intestine, and total worm counts were performed in a cross-sectional study of 30 consecutive feline mortalities. Trichuris were found in 17 of 30 (57%; 95% confidence interval, 39%–74%) of the study cats with a median worm count of 11 (range, 1–170), indicating most cats had a low-intensity infection. Trichuris infection was associated with typhlitis but not consistency of feces or body condition score. In most cats examined, the typhlitis was categorized as mild (10/15, 67%) and, less frequently, moderate (2/15, 13%) or marked (3/15, 20%). The inflammatory infiltrate varied from predominantly eosinophilic (5/15, 33%) to neutrophilic (4/15, 27%), a mixture of eosinophilic and neutrophilic (2/15, 13%), a mixture of neutrophilic and lymphoplasmacytic (1/15, 7%), or a mixture of eosinophilic, neutrophilic, and lymphoplasmacytic (3/15, 20%). In some cats, surface erosions and catarrhal exudate were adjacent to adult worms. These findings are similar to those reported with low-intensity Trichuris infections in other species.

Hydro-Ethanolic Extract of Mentha pulegium Exhibit Anthelmintic and Antioxidant Proprieties In Vitro and In Vivo.

During recent decades, the emergence of chemoresistance among synthetic anthelmintic drugs has increased the interest in screening novel natural anthelmintic compounds derived from plants. The current study is aimed to determine the chemical profile, anthelmintic and antioxidant properties of Mentha pulegium hydro-ethanolic extract. Two tests were used to assess the in vitro anthelmintic activity of the hydro-ethanolic extract of M. pulegium against Haemonchus contortus; egg hatch assay (EHA) and adult worm motility (AWM) assay. M. pulegium extracts at the doses of 500, 1000, 2000 and 4000 mg/kg were evaluated in vivo in mice infected with Heligmosomoides polygyrus. The anthelmintic efficacy was monitored using faecal egg count reduction (FECR) and total worm count reduction (TWCR). The antioxidant activity of M. pulegium extract was evaluated by testing the total antioxidant capacity and the DPPH free radical-scavenging ability. Chromatographic characterization of M. pulegium composition using RP-HPLC revealed the presence of phenolic acids such as syringic acid, ferulic acid and the presence of flavonoid compounds, such as isorhamnetin-3-O-glucoside and kaempferol-3-O-rutinoside. We observed 91.58% inhibition in the EHA at 8 mg/mL after 48 h of incubation (IC50=1.82 mg/mL). In the AWM assay, M. pulegium extract achieved 65.2% inhibition at 8 mg/mL after 8 h. The highest dose (4000 mg/kg) showed a significant nematicidal effect 7 days post-treatment by inducing 60.39% FECR and 71.6% TWCR. We also report strong in vivo antioxidant capacity of the extract, as revealed by a significant increase of the enzymatic activities of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymes in mice infected with H. polygyrus. Together, the results in this paper suggest that M. pulegium possesses anthelmintic properties and could be a potential source of novel compounds for the control of helminth parasites as well as its associated oxidative damage.

Antiparasitic activity of piplartine (piperlongumine) in a mouse model of schistosomiasis

Schistosomiasis is one of the most important parasitic infections in terms of its negative effects on public health and economics. Since praziquantel is currently the only drug available to treat schistosomiasis, there is an urgent need to identify new anthelmintic agents. Piplartine, also known as piperlongumine, is a biologically active alkaloid/amide from peppers that can be detected in high amounts in the roots of Piper tuberculatum. Previously, it has been shown to have in vitro schistosomicidal effects. However, its anthelmintic activity in an animal host has not been reported. In the present work, in vivo antischistosomal properties of isolated piplartine were evaluated in a mouse model of schistosomiasis infected with either adult (patent infection) or juvenile (pre-patent infection) stages of Schistosoma mansoni. A single dose of piplartine (100, 200 or 400 mg/kg) or daily doses for five consecutive days (100 mg/kg/day) administered orally to mice infected with schistosomes resulted in a reduction in worm burden and egg production. Treatment with the highest piplartine dose (400 mg/kg) caused a significant reduction in a total worm burden of 60.4% (P < 0.001) in mice harbouring adult parasites. S. mansoni egg production, a process responsible for pathology in schistosomiasis, was also significantly inhibited by piplartine. Studies using scanning electron microscopy revealed substantial tegumental alterations in parasites recovered from mice. Since piplartine has well-characterized mechanisms of toxicity, is easily available, and is cost-effective, our results indicate that this bioactive molecule derived from medicinal plants could be a potential lead compound for novel antischistosomal agents.

Effect of a newly synthesized quinoline-based compound (PPQ-8) on murine schistosomiasis mansoni.

Schistosomiasis represents a public health problem and praziquantel is the only drug used for treatment of all forms of the disease. Thus, the development of new anti-schistosomal agents is of utmost importance to increase the effectiveness, reduce side effects and delay the emergence of resistance. The present study was conducted to report the therapeutic efficacy of PPQ-8, a new synthetic quinoline-based compound against Schistosoma mansoni. Mice were treated with PPQ-8 at day 49 post infection using two treatment regimens (20 and 40 mg/kg). Significant reductions were recorded in hepatic (62.9% and 83.6%) and intestinal tissue egg load (57.4% and 73.5%), granuloma count (75.4% and 89.1%) and diameter (26.2% and 47.3%), in response to the drug regimens, respectively. In addition, both treatment regimens induced significant decrease in liver (23.3% and 32.8%) and spleen (37.5% and 45.3%) indices. Also, there were significant reductions in mature ova, total worm and female count, which were more prominent with the higher dose. The reduction in the level of nitric oxide in the liver by both therapeutic regimens to 22.5% and 47.2% indicates the anti-oxidant activity of PPQ-8. Bright field microscopic examination of worms recovered from infected and PPQ-8-treated mice showed nearly empty intestinal caeca with no observable changes in the tegument. Our findings hold promise for the development of a novel anti-schistosomal drug using PPQ-8, but further in vitro and in vivo studies are needed to elucidate the possible mechanism/s of action and to study the effect of PPQ-8 on other human schistosomes.

Quantitative Profiling of Lipid Species in Caenorhabditis elegans with Gas Chromatography-Mass Spectrometry.

Gas chromatography-mass spectrometry (GC-MS) enables sensitive detection and relative quantification of fatty acids. In Caenorhabditis elegans, the use of GC-MS can corroborate findings from common staining methodologies, providing great resolution on the lipid species altered in abundance in aging, genetic mutants, or with dietary or pharmacologic manipulation. Here we describe a method to quantitate relative abundance of fatty acids in total worm lipid extracts, as well as a method that quantitates fatty acids following separation into neutral lipid pools (triacylglycerols and cholesteryl esters) versus more polar lipids (phospholipids) by solid-phase extraction (SPE).

Therapeutic efficacy of a newly synthesized benzimidazole compound BTP-OH against murine schistosomiasis mansoni.

Because of the increasingly emerging praziquantel resistance, there is a crucial need to develop new anti-schistosomal agents. This work was conducted to assess the therapeutic efficacy of a new benzimidazole compound (BTP-OH) in mice experimentally infected with Schistosoma mansoni. A total of 40 Swiss albino female mice were divided into an infected untreated group and three infected treated groups (using praziquantel and BTP-OH). The compound activity was evaluated through parasitological, histopathological and scanning electron microscopy studies. Praziquantel and BTP-OH at both doses significantly reduced male (75%, 42.67% and 61.08%, respectively), female (71.45%, 48.94% and 68.13%, respectively) and total worm burden (75.21%, 42.42% and 62.28%, respectively), as well as tissue egg load in the liver (71.22%, 42.12% and 66.04%, respectively). In oogram, praziquantel significantly increased the percentage of dead eggs (65.89%), while BTP-OH significantly reduced the percentage of immature eggs (30.43% and 19.64%). BTP-OH significantly diminished granuloma count (33.87% and 44.77%) and diameter (39.23% and 49.40%), and caused ultrastructural changes in the tegument of adult schistosomes. This study provides evidence for the schistosomicidal efficacy of BTP-OH. However, future studies are needed to elucidate the full mechanisms of action and effects of BTP-OH on other human schistosomes.

Deciphering the enzymatic target of a new family of antischistosomal agents bearing a quinazoline scaffold using complementary computational tools

A previous phenotypic screening campaign led to the identification of a quinazoline derivative with promising in vitro activity against Schistosoma mansoni. Follow-up studies of the antischistosomal potential of this candidate are presented here. The in vivo studies in a S. mansoni mouse model show a significant reduction of total worms and a complete disappearance of immature eggs when administered concomitantly with praziquantel in comparison with the administration of praziquantel alone. This fact is of utmost importance because eggs are responsible for the pathology and transmission of the disease. Subsequently, the chemical optimisation of the structure in order to improve the metabolic stability of the parent compound was carried out leading to derivatives with improved drug-like properties. Additionally, the putative target of this new class of antischistosomal compounds was envisaged by using computational tools and the binding mode to the target enzyme, aldose reductase, was proposed.

AMELIORATIVE EFFECT OF CALOTROPIS PROCERA AND/OR PRAZIQUANTEL ON SCHISTOSOMA MANSONI INFECTED MICE

Seventy albino mice were infected with~ 80 S. mansoni cercariae and were classified into: GI: infected non-treated group, GII: treated with C. procera alcoholic extract after infection (therapeutic), GIII: treated with C. procera aqueous extract after infection (therapeutic), GIV: treated with C. procera alcoholic extract before infection (prophylactic alcoholic), GV: treated with C. procera aqueous extract before infection (prophylactic aqueous), GVI: treated with praziquantel, treated group with praziquantel combined with aqueous extract of C. procera and G.VII: infected and treated with half dose of Praziquantel combined with aqueous plant extract. Seven weeks post infection, all mice were autopsied, and livers and ilea were parasitological examined (Tissue egg load) and histological assessments (Number & size of hepatic granulomas). Schistosomes recovered from all groups were processed to calculate total worm burdens. The results showed that mice treated with C. procera alcoholic and aqueous extracts showed more significant reduction in total worm burden (43.7% & 46.4%), total egg tissue load (60% & 50.7%) and number of hepatic granuloma (45.9% & 55.5%) than mice in prophylactic aqueous or alcoholic groups (38.3% & 36%, 27.2% & 44%, 25.6% & 39%, respectively). Female wormsrecovered from mice of aqueous or alcoholic treated groups showed less fecundity than those recovered from mice of prophylactic groups (1475±181 & 2821±200, corresponding to 3674±1447 & 3023±709, respectively). Mice treated with praziquantel or treated with praziquantel combined with C. procera aqueous extract showed the highest reduction in total tissue egg load (86.4% & 97.4%, respectively). Mice treated with praziquantel combined with C. procera aqueous extract showed higher reduction in total egg tissue (97.4%), number and size of hepatic granuloma (72.3% & 31.4%) than those treated with praziquantel (86.4%, 55.5% &10.8%, respectively).

Anthelmintic effect of Cymbopogon citratus essential oil and its nanoemulsion on sheep gastrointestinal nematodes.

The anthelmintic resistance stimulated the search for strategies for controlling gastrointestinal nematodes, including the use of free essential oils or its nanoemulsion. This study evaluated the anthelmintic efficacy of Cymbopogon citratus essential oil (CcEO) and C. citratus essential oil nanoemulsion (CcEOn). Pysicochemical analyses were performed. The in vitro effect was determined using the egg hatch test (EHT) on Haemonchus contortus and in vivo effect was evaluated in sheep infected with gastrointestinal nematodes. The animals were treated with CcEO (500 mg/kg) or CcEOn (450 mg/kg) for the fecal egg count (FEC) and the determination of worm burden. The main component of CcEO was citral. The CcEO content in the nanoemulsion was 20% (v/v), and the mean particle size was 248 nm. In EHT, CcEO and CcEOn (1.25 mg/mL) inhibited larval hatching by 98.4 and 97.1%, respectively. Three animals treated with CcEO died whereas in the group treated with CcEOn one animal died. The FEC and total worm burden of the treated groups did not differ from the negative control (p>0.05). The CcEOn showed efficacy only on H. contortus (p<0.05). In conclusion, nanoencapsulation reduced toxicity and increased efficacy on H. contortus.

In vitro and in vivo activities of DW-3-15, a commercial praziquantel derivative, against Schistosoma japonicum

BackgroundSchistosomiasis is a debilitating neglected tropical disease that affects approximately 190 million people around the world. Praziquantel (PZQ) is the only drug available for use against all Schistosoma species. Although PZQ has a high efficacy, recognized concerns have prompted the development of new, alternative drugs for repeated use in endemic areas where PZQ efficacy against strains of Schistosoma is reduced. A hybrid drug containing different pharmacophores within a single molecule is a promising strategy. Our earlier in vivo studies showed the significant antiparasitic activity of a praziquantel derivative, DW-3-15, against Schistosoma japonicum. In the present study, DW-3-15 was synthesized in large amounts by a pharmaceutical company and its schistosomicidal efficacy and stability were further confirmed. Parameters such as parasite viability, pairing and oviposition were evaluated in vitro. An in vivo study was conducted to assess the effect of commercial DW-3-15 on worm burden, egg production and diameter of granulomas. Additionally, to gain insight into the mechanism of action for DW-3-15, morphological changes in the tegument of S. japonicum were also examined.ResultsThe in vitro study showed the antiparasitic activity of DW-3-15 against S. japonicum, with significant reductions in viability of adult and juvenile worms, worm pairings and egg output. Compared to PZQ, DW-3-15 induced similar ultrastructural changes and evident destruction of the tegument surface in male worms. In vivo, the oral administration of DW-3-15 at a dose of 400 mg/kg per day for five consecutive days in mice significantly reduced the total worm burden and number of eggs in the liver. Histological analysis of the livers showed a marked reduction in the average diameter of the egg granuloma.ConclusionsOur findings suggest that DW-3-15, a PZQ derivative with the prospect of commercial production, can be developed as a potential promising schistosomicide.

Effect of nanoparticles on the therapeutic efficacy of praziquantel against Schistosoma mansoni infection in murine models.

Praziquantel (PZQ) is the main treatment of Schistosomiasis mansoni. However, resistance to it was described. So, there is a necessity to develop novel drugs or to enhance the present drugs. This work aimed to assess the efficacy of PZQ alone and when loaded on liposomes in treatment of S. mansoni infection by parasitological and histopathological studies in experimental murine models. 112 male laboratories bred Swiss Albino mice were used in this work. They were divided into four groups: Group 1: control group; Group 2: infected then treated by PZQ (500mg/kg) at 7, 30 and 45days post infection; Group 3: infected then treated by liposome encapsulated PZQ (lip.PZQ) (500mg/kg) at 7, 30 and 45days post infection; Group 4: infected then treated by free liposomes at 7, 30 and 45days post infection. The results showed that G3 caused the highest significant reduction of the total worm count, eggs/gram liver tissue and intestine (97.2%, 99.3%, 99.5%) respectively. Followed by G2 (85.1%, 97.6%, 89.8%) respectively. Regarding the histopathological studies, G3 showed the highest significant reduction in number and diameter of hepatic granuloma (97.6% and 98.1%), followed by G2 (77.2% and 75%) when compared to other groups. In conclusion, lip.PZQ is more effective than free PZQ from all aspects especially when administered 45days PI.