Total Worm Burden Research Articles

Effect of Praziquantel on Preventing Delayed Infection of Schistosoma japonicum in Buffaloes and Goats

Schistosomiasis, caused by Schistosoma japonicum, continues to pose a major public health threat in East Asia, with an estimated 71 million people at risk of infection. Domestic animals, especially buffaloes and goats, serve as important reservoir hosts, facilitating the transmission of the parasite to humans. While praziquantel (PZQ) is the first-line treatment for schistosomiasis due to its broad-spectrum efficacy against adult schistosomes, its prophylactic potential is less explored. This study aimed to evaluate the efficacy of PZQ in preventing S. japonicum infection in buffaloes and goats via assessing worm burden, worm size, hematological changes, and immune modulation. In the present study, buffaloes and goats were pretreated with PZQ at various doses (7–25 mg/kg body weight), followed by infection with S. japonicum cercariae. The results showed significant reductions in total worm burden and female worm burden, with one oral administration at 13 mg/kg for buffaloes and one injection at 25 mg/kg for goats offering the most robust protection. Worm length was also significantly reduced in both buffaloes and goats, indicating that PZQ not only prevented infection in this study but also inhibited worm growth. Furthermore, PZQ pretreatment modulated immune responses, as evidenced by increased levels of nitric oxide (NO) and interleukin-2 (IL-2) in buffaloes and Lym% in goats. These findings suggest that PZQ has significant prophylactic potential in livestock, offering a practical solution for reducing schistosome transmission from animals to humans in endemic regions. Additionally, this study indicates that PZQ pretreatment does not contribute to resistance development, as newly established infections are effectively cleared during the initial treatment window.

ئAntiparasitic activity of Cerastes cerastes venom on Schistosoma mansoni infected mice‏

This study investigates whether Cerastes cerastes venom (CCV) administrated at different doses (3 and 6μg/mouse) and times (a week pre-infection, the first week post-infection, and the fifth week post-infection) possesses antischistosomal activity on Schistosoma mansoni infected mice. The results showed that treatment with half lethal dose (6 μg/mouse) of CCV, at various time schedules, led to a significant decrease in the total worm burden. However, quarter lethal dose (3μg/mouse) of CCV showed a significant decrease in the total worm burden only when administered a week pre-infection. The total number of deposited eggs by females of S. mansoni was significantly decreased in the liver and the intestine of mice treated with 3μg/mouse or 6μg/mouse CCV, associated with significant alterations in the oogram pattern with significant elevation in dead eggs levels and significant decrease in the number of mature eggs. Histological examinations illustrated a significant decrease in the number and diameter of hepatic granulomas in high dose (6μg/mouse) CCV-treated groups, while it was significant only a week pre-infection in low dose (3μg/mouse) CCV-treated groups. CCV also caused several tegumental changes in treated female and male worms, including loss of the normal surface architecture, tubercular destruction, loss of tubercles' spines, oedema, erosion, membrane blebbing, and swelling. S. mansoni-infected mice groups treated with CCV (6μg/mouse) a week before infection and at fifth week post-infection had, in all individuals up to a dilution of 1:1600, higher levels of antibodies against adult worm antigen. The current investigation found that C. cerastes venom has potential antischistosomal action in a time and dose-dependent manner (more enhanced antischistosomal effects at a dose of 6 μg and in the group treated in a week before infection), in addition to its potential immunomodulatory effect against schistosomiasis infection. More studies will be required to identify the venom's active ingredients that affect the host's immunology. This information could be used in the future to develop novel antischistosomal therapies.

In vivo antischistosomal activity profiling and efficacy of niosomal Spirulina platensis and praziquantel combined remedy against murine Schistosoma mansoni infection

Schistosomiasis is a serious parasite disease with a high rate of mortality and negative financial impacts in subtropical and tropical locations like Egypt. The goal of this study was to investigate the anti-schistosomal effect of Spirulina platensis (SP) and Spirulina loaded niosomes (SPN), either in the presence or absence of praziquantel (PZQ) against S. mansoni in experimentally infected mice. Six groups have been involved in the study, five groups were infected with S. mansoni cercariae and subjected independently to different treatments of SP, SPN, and PZQ or the preceding two combinations, in addition to one untreated group which acts as a control. At the 8th week, mice were euthanized, and besides a histopathological assessment of the liver granuloma, the number of worms, tissue egg load, and oogram pattern were estimated. To evaluate the condition of the liver oxidative stress, the levels of malondialdehyde and reduced glutathione in liver homogenates were investigated. Additionally, to assess the anti-inflammatory properties, serum cytokines (IFN-γ, TNF-α, IL-13, and IL-10) and CD4+ immunohistochemistry expression were determined. The results demonstrated that each of the investigated parameters was significantly changed by both SPN and/or SPN with PZQ treatments alongside PZQ. The highest therapeutic effect was obtained in SPN combined with a half dose of PZQ which achieved 100 % reduction in both the total worm burden and the highest reduction in the intestinal (93.22 %) and hepatic (94.4 %) egg content, as well, moreover 40.5 % reduction of the granuloma size. Furthermore, serum cytokine levels {(TNF-α (11 ± 0.5 (P ˂ 0.001)), (IFN-γ (19.7 ± 1.2 (P ˂ 0.001)) and (IL-13 (53.65 ± 1.4 (P ˂ 0.001))}, as well as CD4+ cells (6.5 ± 0.65 (P ˂ 0.001)) were reduced. While, IL-10 (61.1 ± 2.1 (P ˂ 0.001)) was increased due to the same treatment additional to its antioxidant properties by reduced lipid peroxidation (LPO) (1.1975 ± 0.05(P ˂ 0.001)) but increased reduced glutathione (GSH) (2.31± 0.15 (P˂0.001)). In conclusion, SPN has a schistosomicidal, antioxidant, and hepatoprotective role. SPN has a strong synergistic effect when combined with PZQ which showed anti-inflammatory action. Hence, SPN + PZQ offers promising alternatives for future schistosomiasis therapeutic research.

Evaluation of the prophylactic and therapeutic efficacies of mucus and tissue nucleoproteins extracted from Biomphalaria alexandrina snails on schistosomiasis mansoni.

Schistosomiasis is a neglected tropical disease with considerable morbidity. The lone effective drug, praziquantel (PZQ), is showing emergence of drug resistance hence, searching for new supportive treatment is crucial. This study aimed to evaluate the efficacy of mucus and nucleoproteins (NPs) extracted from Biomphalaria alexandrina (B. alexandrina) snails on miracidia, cercariae and Schistosoma mansoni (S. mansoni) adults in vitro and assess their experimental in vivo effect through parasitological, histopathological, and biochemical parameters. The in vivo study included 90 male Swiss albino mice. Mice were grouped into 9 groups; G1-G5 were infected and treated with; GI: PZQ, GII: mucus, GIII: combined PZQ and mucus, GIV: NPs, GV: combined PZQ and NPs. Control groups; C1: Non infected non treated (negative control), C2: Infected non treated (positive control), C3: Non infected mucus treated and C4: Non infected NPs treated. The in vitro study proved that the mucus had a better lethal effect on cercariae than miracidia, while NPs had better lethal effect on miracidia. The mucus lethal effect on adults surpassed the NPs as 100% and 60%, respectively. The in vivo study proved that the combined NPs or mucus with PZQ added to the effect of individual PZQ resulting in 100% total worm burden (TWB) reduction. As regard oxidative stress markers, the lowest level of nitric oxide (NO) was shown with combined PZQ and NPs. While, the highest glutathione (GSH) level was produced by individual PZQ. The study concluded that mucus and NPs of B. alexandrina had cercaricidal, miracidicidal and anti-schistosomal effect in vitro and that their combination could be considered a contribution to PZQ potentiality in vivo.

Therapeutic efficacy of candidate antischistosomal drugs in a murine model of schistosomiasis mansoni.

Schistosomiasis is a neglected tropical disease associated with considerable morbidity. Praziquantel (PZQ) is effective against adult schistosomes, yet, it has little effect on juvenile stages, and PZQ resistance is emerging. Adopting the drug repurposing strategy as well as assuming enhancing the efficacy and lessening the doses and side effects, the present study aimed to investigate the in vivo therapeutic efficacy of the widely used antiarrhythmic, amiodarone, and diuretic, spironolactone, and combinations of them compared to PZQ. Mice were infected by Schistosoma mansoni "S. mansoni" cercariae (Egyptian strain), then they were divided into two major groups: Early- [3weeks post-infection (wpi)] and late- [6 wpi] treated. Each group was subdivided into seven subgroups: positive control, PZQ, amiodarone, spironolactone, PZQ combined with amiodarone, PZQ combined with spironolactone, and amiodarone combined with spironolactone-treated groups. Among the early-treated groups, spironolactone had the best therapeutic impact indicated by a 69.4% reduction of total worm burden (TWB), 38.6% and 48.4% reduction of liver and intestine egg load, and a significant reduction of liver granuloma number by 49%. Whereas, among the late-treated groups, amiodarone combined with PZQ was superior to PZQ alone evidenced by 96.1% reduction of TWB with the total disappearance of female and copula in the liver and intestine, 53.1% and 84.9% reduction of liver and intestine egg load, and a significant reduction of liver granuloma number by 67.6%. Comparatively, spironolactone was superior to PZQ and amiodarone in the early treatment phase targeting immature stages, while amiodarone had a more potent effect when combined with PZQ in the late treatment phase targeting mature schistosomes.

Hypobiosis and Development of Haemonchus contortus and Trichostrongylus colubriformis Infection in Lambs under Different Levels of Nutrition

The influence of four levels of dietary supplementation on the development of the immune response and on the biology of Haemonchus contortus and Trichostrongylus colubriformis was evaluated in Dorper lambs under serial artificial infections with 1000 infective larvae (L3) of each species; the supplement was given every 3 days for 12 weeks. For each of the four diets formulated, one infected group (n = 7) and one control group (n = 4) were set up. Diets 1, 2, 3, and 4 contained 0%, 25%, 50%, and 75% of concentrate, respectively. There was an evident immune response to infection in all groups, manifested through eosinophilia and the production of anti-L3 immunoglobulins. There was a significant inverse relationship between the levels of nutrients in the diets and the numbers of late fourth-stage larvae, immature adult stages, and adults of H. contortus. Following 12 weeks of serial infections, most of the H. contortus population was found at the early fourth stage, indicating the occurrence of hypobiosis. The early fourth stage represented 59.5%, 75.8%, 83.3%, and 86.3% of the total Haemonchus worm burden, respectively, in Diets 1, 2, 3, and 4. In the case of T. colubriformis, hypobiosis was not observed, and diet had no influence on the establishment of parasites.

The Existing Drug Nifuroxazide as an Antischistosomal Agent: In Vitro, In Vivo, and In Silico Studies of Macromolecular Targets.

Schistosomiasis is a parasitic disease that afflicts approximately 250 million people worldwide. There is an urgent demand for new antiparasitic agents because praziquantel, the only drug available for the treatment of schistosomiasis, is not universally effective and may derail current progress toward the WHO goal of eliminating this disease as a public health problem by 2030. Nifuroxazide (NFZ), an oral nitrofuran antibiotic, has recently been explored to be repurposed for parasitic diseases. Here, in vitro, in vivo, and in silico studies were conducted to evaluate the activity of NFZ on Schistosoma mansoni. The in vitro study showed significant antiparasitic activity, with 50% effective concentration (EC50) and 90% effective concentration (EC90) values of 8.2 to 10.8 and 13.7 to 19.3 μM, respectively. NFZ also affected worm pairing and egg production and induced severe damage to the tegument of schistosomes. In vivo, a single oral dose of NFZ (400 mg/kg of body weight) to mice harboring either prepatent or patent S. mansoni infection significantly reduced the total worm burden (~40%). In patent infection, NFZ achieved a high reduction in the number of eggs (~80%), but the drug caused a low reduction in the egg burden of animals with prepatent infection. Finally, results from in silico target fishing methods predicted that serine/threonine kinases could be one of the potential targets for NFZ in S. mansoni. Overall, the present study revealed that NFZ possesses antischistosomal properties, mainly in terms of egg burden reduction in animals with patent S. mansoni infection. IMPORTANCE The increasing recognition of the burden imposed by helminthiasis, associated with the limited therapeutic arsenal, has led to initiatives and strategies to research and develop new drugs for the treatment of schistosomiasis. One of these strategies is drug repurposing, which considers low-risk compounds with potentially reduced costs and shorter time for development. In this study, nifuroxazide (NFZ) was evaluated for its anti-Schistosoma mansoni potential through in vitro, in vivo, and in silico studies. In vitro, NFZ affected worm pairing and egg production and induced severe damage to the tegument of schistosomes. In vivo, a single oral dose of NFZ (400 mg/kg) to mice harboring either prepatent or patent S. mansoni infection significantly reduced the total worm burden and egg production. In silico investigations have identified serine/threonine kinases as a molecular target for NFZ. Collectively, these results implied that NFZ might be a potential therapeutic candidate for the treatment of schistosomiasis.

Pattern and repeatability of ascarid-specific antigen excretion through chicken faeces, and the diagnostic accuracy of coproantigen measurements as compared with McMaster egg counts and plasma and egg yolk antibody measurements in laying hens

BackgroundA coproantigen enzyme-linked immunosorbent assay (ELISA) has recently been proposed for detecting ascarid infections in chickens. The excretion pattern of ascarid antigens through chicken faeces and the consistency of measurements over the course of infections are currently unknown. This study evaluates the pattern and repeatability of worm antigen per gram of faeces (APG) and compares the diagnostic performance of the coproantigen ELISA with a plasma and egg yolk antibody ELISA and McMaster faecal egg counts (M-FEC) at different weeks post-infection (wpi).MethodsFaecal, blood and egg yolk samples were collected from laying hens that were orally infected with a mix of Ascaridia galli and Heterakis gallinarum eggs (N = 108) or kept as uninfected controls (N = 71). Measurements including (a) APG using a coproantigen ELISA, (b) eggs per gram of faeces (EPG) using the McMaster technique and (c) ascarid-specific IgY in plasma and in egg yolks using an ascarid-specific antibody ELISA) were performed between wpi 2 and 18.ResultsTime-dependent significant differences in APG between infected and non-infected laying hens were quantified. At wpi 2 (t(164) = 0.66, P = 1.00) and 4 (t(164) = −3.09, P = 0.094) no significant differences were observed between the groups, whereas infected hens had significantly higher levels of APG than controls by wpi 6 (t(164) = −6.74, P < 0.001). As indicated by a high overall repeatability estimate of 0.91 (CI = 0.89–0.93), APG could be measured consistently from the same individual. Compared to McMaster and antibody ELISA, coproantigen ELISA showed the highest overall diagnostic performance (area under curve, AUC = 0.93), although the differences were time-dependent. From wpi 6 to 18 coproantigen ELISA had an AUC > 0.95, while plasma IgY ELISA showed the highest diagnostic performance in wpi 2 (AUC = 0.95). M-FEC had the highest correlation with total worm burden, while APG had highest correlations with weights and lengths of A. galli.ConclusionAscarid antigen excretion through chicken faeces can be measured with high accuracy and repeatability using a coproantigen ELISA. The antigen excretion increases over time, and is associated with worm maturation, particularly with the size of A. galli. Our results suggest the necessity of complementary use of different diagnostic tools for a more accurate diagnosis of infections.Graphical

Antischistosomal effects of green and chemically synthesized silver nanoparticles: In vitro and in vivo murine model

Schistosomiasis is one of the most important neglected tropical diseases in Africa, caused by blood fluke, Schistosoma sp. The use of nanotechnology in the treatment of this type of disease is urgently important to avoid the unwanted side effects of chemotherapy. The present study aimed to evaluate the efficacy of green silver nanoparticles (G-AgNPs), fabricated by (Calotropis procera), comparing with both chemically prepared silver ones (C-AgNPs) and Praziquantel (PZQ) treatments. The study included in vitro and in vivo evaluations. In in vitro study, 4 groups of schistosome worms were exposed to treatments as follows: the first one with a dose of PZQ (0.2 µg/ml), the 2nd and 3rd groups with different concentrations of G-AgNPs and C-AgNPs, respectively and the last one act as a negative control group. In in vivo study, six groups of mice were infected and then treated as follows: the first one with a dose of PZQ, the second with G-AgNPs, the third with C-AgNPs, the fourth with G-AgNPs plus a half dose of PZQ, the fifth with C-AgNPs accompanied by a half dose of PZQ, and the last group acted as a positive control group. The parasitological (worm burden, egg count & oogram) and histopathological parameters (hepatic granuloma profile) were used to evaluate antischistosomal activities in experimental groups. Additionally, the subsequent ultrastructural alterations were observed in adult worms using scanning electron microscopy (SEM). Transmission electron microscopy analysis showed that G-AgNPs and C-AgNPs have 8–25 and 8–11 nm in diameter, respectively, besides, fourier transform infrared analysis (FTIR) revealed the presence of organic compounds (aromatic ring groups) which act as capping agents around the surfaces of biogenic silver nanoparticles. In in vitro experiment, adult worms incubated either with G-AgNPs or C-AgNPs at concentrations higher than 100 µg/ml or 80 µg/ml, respectively, showed full mortality of parasites after 24 h. In the infected treated groups (with G-AgNPs plus PZQ & C-AgNPs plus PZQ) showed the most significant reduction in the total worm burdens (92.17% & 90.52%, respectively). Combined treatment with C-AgNPs and PZQ showed the highest value of dead eggs (93,6%), followed by G-AgNPs plus PZQ-treated one (91%). This study showed that mice treated with G-AgNPs plus PZQ significantly has the highest percentage of reduction in granuloma size and count (64.59%, 70.14%, respectively). Both G-AgNPs plus PZQ-treated & C-AgNPs plus PZQ treated groups showed the highest similar values of reduction percentage of total ova count in tissues (98.90% & 98.62%, respectively). Concerning SEM, G-AgNPs-treated worms showed more variability in ultrastructural alterations than G-AgNPs plus PZQ-treated one, besides, worms treated with C-AgNPs plus PZQ exhibited the maximum level of contractions or (shrinkage) as a major impact.

Ascaridia galli eggs obtained from fresh excreta, worm uteri or worms cultured in artificial media differ in embryonation capacity and infectivity

Ascaridia galli infection models use eggs isolated from chicken excreta, worm uteri and worms cultured in artificial media. The aim of this study was to compare the infectivity of A. galli eggs isolated from these sources under two infection regimens. A 3 × 2 factorial arrangement was employed to test the infectivity of A. galli eggs from the three sources and two modes of infection (single or trickle infection). One hundred and fifty-six Isa-Brown one day-old cockerels randomly assigned to the six treatment groups (n = 26) were orally infected with embryonated A. galli eggs obtained from the three A. galli egg sources (worm uteri, excreta or eggs shed in vitro) administered either as single dose of 300 eggs at one day-old or trickle infected with 3 doses of 100 eggs over the first week of life. Twenty-two negative control birds remained uninfected. Eggs obtained from cultured worms or excreta exhibited a higher embryonation capacity (P = 0.003) than eggs obtained from worm uteri. There were higher worm establishment (infectivity) rates from embryonated eggs originating from cultured worms and worm uteri compared with eggs obtained from fresh excreta (P < 0.0001). Trickle infection resulted in a significantly higher total worm burden (P = 0.002), establishment rate (P = 0.002) and excreta egg counts (EEC, P = 0.025) than single infection. Worm length was greater in birds infected with embryonated eggs from excreta than from uteri or cultured worms (P < 0.0001). However, mode of infection did not affect worm length (P = 0.719) and weight (P = 0.945). A strong significant positive linear correlation was observed between EECs and female worm counts at 12 weeks of post infection sampling (r = 0.75; P < 0.0001). Body weight of birds was negatively correlated with both worm burden (r = − 0.21; P < 0.01) and EEC (r = − 0.20; P < 0.05) at 12 weeks post infection. In conclusion, our results show that eggs shed by cultured worms or isolated from worm uteri had greater infective capacity than eggs harvested from excreta and that trickle rather than bolus infection resulted in higher worm establishment. These factors should be taken into account when considering artificial infection protocols for A. galli.

In Vivo Evaluation of an Antibody-Functionalized Lipoidal Nanosystem for Schistosomiasis Intervention.

This study employed nanotechnological techniques to design and develop a praziquantel nanoliposomal (NLP) system and surface-functionalized the NLP with anti-calpain antibody (anti-calpain-NLP) for targeted praziquantel (PZQ) delivery in the treatment of schistosomiasis. Anti-calpain-NLPs were prepared and validated for their physicochemical parameters, in vitro and in vivo toxicity, drug entrapment efficiency (DEE), drug loading capacity (DLC), drug release, and parasitological cure rate. The particle sizes for the formulated nanoliposomes ranged from 88.3 to 92.7 nm (PDI = 0.17–0.35), and zeta potential ranged from −20.2 to −31.9 mV. The DLC and DEE ranged from 9.03 to 14.16 and 92.07 to 94.63, respectively. The functionalization of the nanoliposome surface was stable, uniform, and spherical. Fourier-transform infrared (FTIR), thermal behavior and X-ray powder diffraction (XRPD) analysis confirmed that the anti-calpain antibody and PZQ were attached to the surface and the nanoliposomes inner core, respectively. The drug sustained release was shown to be 93.2 and 91.1% within 24 h for NLP and anti-calpain-NLP, respectively. In the in vitro analysis study, the nanoliposome concentrations range of 30 to 120 μg/mL employed revealed acceptable levels of cell viability, with no significant cytotoxic effects on RAW 264.7 murine macrophage as well as 3T3 human fibroblast cells. Biochemical markers and histopathological analysis showed that the formulated nanoliposomes present no or minimal oxidative stress and confer hepatoprotective effects on the animals. The cure rate of the anti-calpain-NLP and PZQ was assessed by parasitological analysis, and it was discovered that treatment with 250 mg/kg anti-calpain-NLP demonstrated greater activity on the total worm burden, and ova count for both the juvenile and adult schistosomes in the intestine and liver of infected mice. The findings so obtained supported the ability of oral anti-calpain-NLP to target young and adult schistosomes in the liver and porto-mesenteric locations, resulting in improved effectiveness of PZQ.

Differences in the protection elicited by a recombinant Teladorsagia circumcincta vaccine in weaned lambs of two Canarian sheep breeds

Gastrointestinal nematode (GIN) infections are a serious drawback on small ruminant production. Since anthelmintic resistance has extended, optimisation of alternative non-chemical control strategies has attracted interest. Recently, a prototype recombinant vaccine protected immunologically mature sheep from Texel-cross and Canaria Sheep breeds against Teladorsagia circumcincta. The level of protective immunity stimulated by the vaccine varied between individuals and with age. Previous studies suggest that Canaria Hair Breed (CHB) sheep is naturally resistant to GIN infection, with some evidence suggesting that this protection is present in young lambs. Here, we sought to enhance this resistance by immunising three-month-old CHB lambs with a T. circumcincta prototype recombinant vaccine. Following vaccination and a larval challenge period, levels of protection against T. circumcincta infection were compared in CHB lambs with Canaria Sheep (CS) lambs (a breed considered less resistant to GIN). Lambs from the resistant CHB breed appeared to respond more favourably to vaccination, shedding 63% fewer eggs over the sampling period than unvaccinated CHB lambs. No protection was evident in CS vaccinated lambs. At post-mortem, CHB vaccine recipients had a 68% reduction in mean total worm burden, and female worms were significantly shorter and contained fewer eggs in utero compared to unvaccinated CHB lambs. A higher anti-parasite IgG2 level was detected in immunised CHB lambs compared to unvaccinated control CHB animals, with data suggesting that IgA, globular leucocytes, CD45RA+, CD4+ and CD8+ T cells are implicated in this protective response. The development of effective immunity in vaccinated CHB lambs did not reduce lamb growth rate as immunised CHB lambs had a significantly higher average daily weight gain after challenge than their unvaccinated counterparts. Therefore, the protection of CHB lambs was enhanced by immunisation at weaning, suggesting a synergistic effect when combining vaccination with presumed genetic resistance.

Schistosomicidal efficacy of bee venom-loaded pluronic F127 nanomicelles in S. mansoni infected CD1 mice

This study reports a nanoformulation for avoiding the high-dose problems of bee-venom (BV) via encapsulation inside pluronic F127 (F127) nanoparticles (NPs) for treatment of schistosomiasis. After three weeks of treatment, the obtained data showed a reduction in the total worm burden, oogram pattern and ova count compared with the infected control. Moreover, the immunomodulatory functions of BV-loaded NPs were observed via stimulating the innate immune responses (IL-33), T helper (Th)-1 immunity (TNF-α) and Th-2 (IL-10). All treatments induced a reduction in the number and diameter of granuloma, while BV-loaded NPs induced the formation of new hepatic bile ductules. Both F127 NPs and BV-loaded NPs induced a significant decrease in liver fibrosis area percentage compared with the infected control. Free BV showed a limited effect on the S. mansoni larvae, while BV-loaded and plain F127 NPs showed remarkable schistosomicidal effects on the adult parasites.

Praziquantel-encapsulated niosomes against Schistosoma mansoni with reduced sensitivity to praziquantel.

Introduction: Praziquantel (PZQ) is the only commercially available drug for schistosomiasis. The current shortage of alternative effective drugs and the lack of successful preventive measures enhance its value. The increase in the prevalence of PZQ resistance under sustained drug pressure is, therefore, an upcoming issue.Objective: To overcome the tolerance to PZQ using nanotechnology after laboratory induction of a Schistosoma mansoni isolate with reduced sensitivity to the drug during the intramolluscan phase.Materials and methods: Shedding snails were treated with PZQ doses of 200 mg/kg twice/ week followed by an interval of one week and then repeated twice in the same manner. The success of inducing reduced sensitivity was confirmed in vitro via the reduction of cercarial response to PZQ regarding their swimming activity and death percentage at different examination times.Results: Oral treatment with a single PZQ dose of 500 mg/kg in mice infected with cercariae with reduced sensitivity to PZQ revealed a non-significant reduction (35.1%) of total worm burden compared to non-treated control mice. Orally inoculated PZQ- encapsulated niosomes against S. mansoni with reduced sensitivity to PZQ successfully regained the pathogen’s sensitivity to PZQ as evidenced by measuring different parameters in comparison to the non-treated infected animals with parasites with reduced sensitivity to PZQ. The mean total worm load was 1.33 ± 0.52 with a statistically significant reduction of 94.09% and complete eradication of male worms. We obtained a remarkable increase in the percentage reduction of tissue egg counts in the liver and intestine (97.68% and 98.56%, respectively) associated with a massive increase in dead eggs and the complete absence of immature stages.Conclusion: PZQ-encapsulated niosomes restored the drug sensitivity against laboratory- induced S. mansoni adult worms with reduced sensitivity to PZQ.

Brazilian green propolis reduces worm burden and hepatic granuloma formation in a Schistosoma mansoni experimental murine model.

Characterized as an acute and chronic parasitic disease, schistosomiasis mansoni has as its central pathology the formation of hepatic granulomas in response to the parasite's eggs trapped in the host's liver. In recent years, research on propolis has grown; however, there is little anthelmintic work on this bee product. In the propolis scenario, Brazilian ones receive attention, with green and red propolis standing out. This study aims to evaluate in vivo the standardized extract of Brazilian green propolis (Pex) against Schistosoma mansoni. The in vivo antiparasitic activity of Pex was conducted in female BALB/c mice infected with S. mansoni and of the three groups treated with Pex (300mg/kg); G2 (35th to 42nd dpi) reduced the total worm burden by 55.32%, followed by G3 (42nd to 49th dpi) and G4 (49th to 56th dpi), with about 46%. Furthermore, G2 significantly reduced the total egg load in the ileum (59.33%) and showed an increase in the dead eggs. Similarly, histological analysis of the livers showed a significant reduction in the number and diameter of the granulomas. Based on these results, there is an interesting schistosomicidal activity of Pex and its potential against the formation of hepatic granulomas, paving the way for more detailed studies of propolis in the animal model of schistosomiasis mansoni.

Schistosomiasis mansoni: A new therapeutic target for ubiquinol, a natural inhibitor of neutral magnesium-dependent sphingomyelinase in murine model.

Constituting the host-parasite interface and playing a censorious role in host immune response modulation and parasite survival, tegument represents a crucial target for many antischistosomal drugs. Sphingomyelin forms a stable outer leaflet of tegumental membrane-lipid bilayer. Neutral magnesium‏-dependent sphingomyelinase (Mg2+-nSMase) is a key enzyme in sphingomyelin breakdown was identified in schistosomes. We investigated the in vivo efficacy of ubiquinol, a natural inhibitor of Mg2+-nSMase, in free and niosomes-encapsulated forms, through five-day and 15-day regimens on the early and late Schistosoma mansoni parasitic stages, respectively, compared to PZQ. Oral administration of 300 mg/kg/day ubiquinol-encapsulated niosomes (U-N) showed significant deterioration of the parasitic growth and development in the term of reduction of lung schistosomula burden (39.12%), adult worm burden (50.81%), hepatic and intestinal tissue-egg counts (80.89% and 75.54%, respectively). PZQ and free ubiquinol regimens reported reductions in lung schistosomula counts (45.36% and 22.90%, respectively) and total worm burdens of 86.28% and 24.58%, respectively. U-N therapy revealed worms de-pairing and remarkable diminution in female worms’ perimeters and fecundity. Scanning electron microscope revealed disruption of tegumental ridges with excessive longitudinal corrugation. Transmission electron microscope showed testicular and ovarian parenchymal degeneration, signs of immaturity and cell apoptosis. Indirect immunofluorescence assay approved parasite's tegumental changes. Remarkable reduction of granulomas size with amelioration of hepatic pathology and fibrosis were assumed to be attributed to the anti-inflammatory and anti-oxidant properties of ubiquinol. These findings with the drug safety profile suggest that U-N could be a promising candidate for a new antischistosomal drug development.

In Vivo Assessment of the Antischistosomal Activity of OPUNTIA FICUS-INDICA Flowers and Their Chemical Constituents

Hepatic schistosomiasis is the most well-known form of chronic disease, with a wide variety of clinical symptoms. The aim of this study was to assess the schistosomicidal effect of the aqueous methanolic extract of Opuntia ficus-indica flowers in-vivo regarding disease progression in a comparative experimental study to praziquantel (PZQ). Phytochemical investigation of flowers extract resulted in thirteen phenolic and flavonoid compounds. Structures of these compounds were elucidated by UV and 1D⁄2D 1H⁄ 13C NMR spectroscopy and compared with the literature data. From the 49th day after infection, mice infected with Schistosoma mansoni were given the extract (200 mg/kg) orally every day for 5 days, whereby the Praziquantel (500 mg/kg) was used as reference drug. The parasitological parameters (total worm burden, tissue egg load and oogram pattern) per gram of liver or intestinal tissue of the infected and the treated mice were counted. A histopathological examination of the liver granuloma took place as well. Opuntia ficus-indica extract caused a substantial decrease in the number of worms and eggs (%); the extract also decreased worm and egg burdens moderately. The results demonstrated the flower extract as a promising antischistosomal activity due to the parasitological and histopathological changes induced, besides it highlights the importance of its polyphenolic constituents.

Antischistosomal effects of Ficus carica leaves extract and/or PZQ on Schistosoma mansoni infected mice.

Currently, praziquantel (PZQ) is the only drug of choice used for treatment of human schistosomes because of its safety and broad-spectrum activity. It is reported that the repeated chemotherapy is complicated by the occurrence of drug resistance to schistosomiasis. So there is an urgent need to develop newdrug combinations therapy. The current study aimed to evaluate antischistosomal activity of F. carica leaves extract alone or in combination with PZQ on Schistosoma mansoni infected mice. Mice were experimentally infected with Schistosoma mansoni and orally administrated 6weeks' post-infection with Fig leaves extract and/or PZQ. Schistosoma mansoni (S. mansoni)-infected mice were separated into four groups: untreated (I), treated with PZQ in dose of 200mg/kg bw (II), treated with Fig leaves extract dose of 400mg/kg bw (III). Group IV was treated with dose of Fig leaves extract-PZQ as in groups II and III, respectively. The effect was detected parasitologically using ova count technique and oogram pattern in intestine and liver. The greatest antischistosomal effect was achieved using orally administered Fig leaves extract-PZQ as indicated by total worm burden, tissue egg count and oogram pattern. Fig leaves extract + PZQ induced the therapeutic efficacy over the PZQ dose alone in intestine and liver as shown by a complete absence of immature worms, a very high reduction in the total numbers of tissue egg load (59.81% vs. 61.43% & 67.96% vs. 73.46%), mature eggs (37.86 ± 1.4 vs. 34.14 ± 1.9) and increasing in the total number of dead eggs (62.14 ± 1.4vs.67.29 ± 1.76). The results suggested the curcumin in combination with PZQ as a strong schistosomicidal regimen againstS. mansoni. In addition, F. carica leaves extract is a promising for PZQ potentiating its antischistosomal action in animal model infected with S. mansoni. Therefore, the present work conclude that combined treatment has a synergetic effect and could be more promising in the management of schistosomiasis.

The Therapeutic role of Thymoquinone Bioactive Compound as Target Natural Product from Nigella sativa Loaded with Chitosan Nanoparticles on Schistosomiasis

Background: Schistosoma mansoni is a trematode helminth responsible for liver fibrosis or cirrhosis. Aim of the work: In the present work natural products Thymoquinone loaded with chitosan nanoparticle (TQ/ChNP)) (TQ/ChNP) were used to determine their therapeutic effect on S. mansoni infection. Materials and methods: A total of 40 healthy Swiss albino mice, 20-25 g in weight, procured from Theodor Bilharz Research Institute (TBRI) Imbaba, Egypt's Schistosome Biological Supply Center (SBSC). Results: The infected mice treated with TQ/ChNP showed a significant decrease in the total worm burden. Treatment with TQ/ChNP had a highly significant effect on mature worm burden, TQ/ChNP in prophylactic and therapeutic doses significantly increased the mean number of dead ova in comparison to control. TQ/ChNP had a high decrease effect on ova count in intestinal tissue and a moderate reduction on ova count in hepatic tissue. Prophylactic dose gave a high reduction effect on ova count in intestinal tissue. As regards the size of hepatic granuloma, TQ/ChNP had the highest significant reduction on mean granuloma diameter with noticeable improvement of hepatic pathology. TQ/ChNP treated group showed observable improvement of liver pathology with mild degeneration and slight-sized fibrocellular. Conclusion: Based on the outcome of this study, TQ/ChNP proved to have potential bioactivity against S. mansoni adult stages and its potentiality in improving hepatic pathology. Efficacy of TQ/ChNP to postpone progression in chronic liver diseases must be considered as preventive medicine in patients with hepatic disorders.

Effect of short- and long-term immunization of recombinant disorganized muscle protein-1 (rDIM-1) against human filarial parasite Brugia malayi in rodents

Objective: To evaluate the effect of short-term and long-term immunization of recombinant disorganized muscle protein-1 (rDIM-1) in rodents against human filarial parasite Brugia malayi. Methods: Recombinant Brugia malayi DIM-1 (rDIM-1bm) protein was cloned, expressed and purified using a Ni-NTA affinity column. Mastomys coucha were immunized with rDIM-1bm in three immunization schedules: short-term (3-dose of rDIM-1bm), and long-term (booster doses till 3- and 6-week) and subsequently challenged with infective third-stage larvae of filarial parasite Brugia malayi (L3). Microfilaraemia was monitored in L3 exposed groups on day 90 post larval inoculation (p.l.i.) and continued till day 205 p.l.i. On day 205 p.l.i. all the infected animals were killed and total worm burden was estimated. Cellular proliferative response, macrophage activity, nitric oxide (NO) release, specific IgG and its subtypes, IgE, IgA and Th1 (IFN-γ, TNF-α and IL-2) and Th2 (IL-4, IL-5, IL-6, IL-10 and IL-13) cytokine release were determined. Results: Of the 3 different immunization schedules, short-term immunization (3-dose schedule) showed better reduction in microfilarial burden (36%-63%) in the peripheral circulation, adult worm load (52%), whereas long-term immunization (3- and 6-week schedule) exerted less effect on peripheral microfilariae count (9%-58%), and adult worm burden (9%-12.5%). Short-term immunization resulted in upregulation of cellular proliferation, macrophages activity, NO release, specific IgG, IgG1, IgG2a, IgG2b, IgE and IgA levels and both Th1 (IFN-γ, TNF-α and IL-2) and Th2 (IL-4, IL-5, IL-6, IL-10 and IL-13) cytokine release whereas long-term immunization (3- and 6-week schedule) exerted less effect on parasite burden and showed mixed immunological responses. None of the rDIM-1bm administration schedules induced any pathology in lymphoid tissues, or alteration in mast cell number and granularity. Conclusions: The short-term immunization with rDIM-1bm (3-dose schedule) induces robust immune responses and protects the host from filarial parasite infection.