Evaluation of the effect of guanabenz-loaded nanoparticles on chronic toxoplasmosis in mice.

Chronic toxoplasmosis which is positively correlated with many neuropsychiatric problems has no curative treatment till now; due to the resistant tissue cysts especially in the brain. In search of an effective treatment, guanabenz-loaded polyethylene glycol poly lactic-co-glycolic acid (PEG-PLGA) nanoparticles was evaluated against chronic experimental toxoplasmosis. For this purpose, each mouse was infected with 10 cysts of Toxoplasma gondii (ME 49 strain). Treated mice received either guanabenz alone (5 mg/kg/day) in subgroup IIa or guanabenz-loaded nanoparticles by full dose in subgroup IIb or guanabenz-loaded nanoparticles by the half dose (2.5 mg/kg/day) in subgroup IIc. Subgroup Ie was treated by pyrimethamine and sulfadiazine. The treatment started on day 25 post-infection for 19 successive days. Then Parasitological, histopathological, immunohistochemical, immunological and ultrastructural morphological studies were performed. The results showed that: subgroup IIb showed the highest statistically significant reduction in the neuroinflammation and brain tissue cysts (77%) with a significant higher efficacy in comparison with pyrimethamine and sulfadiazine and showed the highest level of IFN-γ, while the lowest level was in subgroup IIa. All group II mice showed similar changes of depression and compression of the wall of the cyst. This is marked in subgroup IIb with release of crescent shaped bradyzoite outside the cyst. PEG-PLGA nanoparticles had no toxic effect on the liver or the kidney of the mice. It could be concluded that guanabenz-loaded PEG-PLGA nanoparticles could be promising and safe for treatment of chronic toxoplasmosis.

The synergetic potential of Lactobacillus delbrueckii and Lactobacillus fermentum probiotics in alleviating the outcome of acute toxoplasmosis in mice.

Toxoplasmosis is an immunologically complex disease, particularly in immunocompromised patients. Although there are several therapeutic regimens for such disease, the majority of them have many drawbacks. Therefore, it is of utmost importance to improve the current regimen in an effort to achieve a well-tolerated therapy while also enhancing the host immune response. Famous for their immunomodulatory effect, Lactobacillus delbrueckii and Lactobacillus fermentum probiotics were chosen to be evaluated in this study as an adjuvant therapy against the virulent RH Toxoplasma gondii (T. gondii) strain. Experimental mice were divided into control and treated groups. The control group was further subdivided into two groups: group I: 10 uninfected mice and group II: 20 infected untreated mice. The treated experimental group was subdivided into three groups (20 mice each); group III: sulfamethoxazole-trimethoprim (SMZ-TMP) treated, group IV: probiotics treated, and group V: SMZ-TMP combined with probiotics. The results obtained revealed that combined therapy increased survival rate and time up to 95% and 16 days, respectively, with an 82% reduction of tachyzoites and marked distortion, as detected by the scanning electron microscope (SEM). Additionally, combined therapy alleviated the severity and the extent of the inflammatory cells' infiltration, thereby reducing hepatocyte degeneration. Intriguingly, serum IF-γ level showed a significant increase to 155.92 ± 10.12 ng/L with combined therapy, reflecting the immunological role of the combined therapy. The current results revealed that probiotics have a high adjuvant potential in alleviating the impact of toxoplasmosis. Using probiotics as a synergistic treatment to modulate conventional therapy in systemic toxoplasmosis may gain popularity due to their low cost and current availability.

Niosomes for enhanced activity of praziquantel against Schistosoma mansoni: in vivo and in vitro evaluation.

Praziquantel (PZQ) is recommended by the WHO as the first line in treatment of schistosomiasis. Unfortunately, it exhibits low oral bioavailability which can compromise its efficacy. Nanostructures showed promising potential to overcome this problem. Accordingly, the aim of this study was to investigate the effect of niosomal encapsulation of PZQ on its activity on Schistosoma mansoni in vitro and in vivo. PZQ was encapsulated in niosomal formulation comprising span 60, cholesterol with peceol being included as absorption enhancer. The in vitro work determined the schistosomicidal activity and morphological changes after incubation with drug solution or PZQ-niosomes. The in vivo study utilized infected mice which received PZQ orally as solution or as niosomes. The activity was assessed by monitoring egg and worm count in addition to histopathological and immunohistochemical studies. The in vitro studies revealed that niosomes alone caused a 30% death of adult parasites and caused completely coiled body, destruction, and peeling of tubercles and spines, with flattening and effacement of gynecophoric canal, blebbing with niosomes vesicles attached to it. Niosomes containing PZQ at a concentration of 0.001 µg/ml increased the death from 30 to 50% with the corresponding PZQ solution causing only 10% death. The in vivo study reflected of niosome-PZQ over PZQ solution as indicated from significant reduction of adult worm count, hepatic and intestinal egg depositions, hepatic granuloma size, and numbers, with marked reduction of vascular endothelial growth factor expression. The study introduced niosomes as promising carriers for enhanced activity of PZQ.

The interaction of Schistosoma mansoni infection with diabetes mellitus and obesity in mice.

Human schistosomiasis is one of the most prevalent parasitic diseases worldwide. Various host factors can affect the host-parasite interactions. Therefore, the aim of the present work was to determine the parasitological, histopathological, biochemical, and immunological status of Schistosoma mansoni-infected hosts with metabolic disorders to identify the underlying possible mechanisms of these comorbidities. The study animals were divided into four groups. Group I represented the control groups, namely, the normal control group, the S. mansoni-infected control group, and the noninfected type 1 diabetes (T1DM), type 2 diabetes (T2DM), and obesity groups. The mice of the other three groups underwent induction of T1DM (Group II), T2DM (Group III) and obesity (Group IV) before being infected with S. mansoni. All mice were subjected to body weight measurement, blood glucose and insulin assessment, parasitological evaluation of adult worm count, tissue egg count and intestinal oogram. Histopathological and immunohistochemical study using anti-glial fibrillary acidic protein (GFAP) in hepatic stellate cells (HSCs) and image analysis of Masson's trichrome-stained liver sections using ImageJ (Fiji) software were carried out. Additionally, immunological analysis of tumour necrosis factor (TNF) beta, interleukin-5 (IL-5), IL-10, Forkhead box P3 (FOXP3) and pentraxin 3 (PTX3) levels besides biochemical study of total lipid profile were evaluated. The present study revealed a significant increase in the adult worm count and tissue egg output in the obesity group compared to the infected control group. The oogram of counted eggs showed prevalence of immature eggs in T1DM group, while T2DM and obese groups showed prevalence of mature eggs. The fibrosis area percentage showed significant increase in T2DM and obese groups while it was decreased in T1DM group in comparison to infected control group. Our data also showed significant increase in the levels of TNF-ß, IL-5, PTX3 in T1DM, T2DM and obesity groups in comparison to infected control group, whilst the levels of FOXP3 and IL-10 were increased in the infected groups in comparison to their noninfected controls. Moreover, infected T1DM, T2DM and obesity groups showed higher blood glucose and lipid profile in comparison to the infected control group. However, these parameters were improved in comparison to their noninfected controls. In sum, induction of T2DM and obesity increased tissue egg counts, mature egg percentage, and fibrosis density, while schistosome infection induced changes in the lipid profile and blood glucose levels in infected diabetic and obese groups and impacted favorably insulin levels in obese mice. By better understanding the complexities of host-parasite interactions, efforts to reduce the burden of these debilitating diseases can be improved.

Genetic polymorphism of glutathione S-transferases M1 and T1 in Egyptian patients with bilharzial bladder cancer.

OBJECTIVE: To assess the influence of glutathione S-transferases M1 and T1 (GSTM1 and T1) genotype on the risk of bladder cancer in patients with urinary bilharziasis. MATERIALS AND METHODS: This study was designed as a case-control study that involved 60 individuals who were enrolled into 3 equal groups. The first one included patients with bilharzial bladder cancer, the second one had those with nonmalignant urinary bilharziasis, and the last one was the control group. All of the participants were adult males, nonsmokers, and with matched ages. All of them underwent an assessment of the serum level of the total GST concentration and the polymerase chain reaction (PCR) was used for determination of the GSTM1 and T1 genotypes. RESULTS: The lower most GST enzyme concentration was reported in patients with bilharzial bladder cancer (26 +/- 4.4 ng/ml) with significant difference between it and that of the second group (36.8 +/- 4.1 ng/ml, P < 0.05) and that of the controls (40.4 +/- 4 ng/ml, P < 0.005). The PCR results have demonstrated that the frequency of combined GSTM1 and T1 genes deletion (M1-ve T1-ve) was significantly higher in cases of bladder cancer (40%) than those of the controls (5%, P < 0.005) and those of the second group (10%, P < 0.05). The unconditional logistic regression test revealed that patients with urinary bilharziasis and combined GSTM1 and T1 genes deletion are at a significant risk for malignant transformation (OR = 6.3, P < 0.05). CONCLUSIONS: Patients with urinary bilharziasis and GSTM1-ve and T1-ve genes might be at increased risk of bladder cancer. However, larger studies are needed for confirmation of these results.

An experimental study for evaluating the efficacy of cercarial vaccine against Schistosoma mansoni.

This study assessed the effectiveness of autoclaved cercarial vaccine (ACV) in protection against Schistosoma mansoni infection in 125 Swiss albino mice classified into two main groups: GI: a control group. GII: a test vaccinated with ACV, in a single dose of 0.1 ml of 10(4) ml ACV (G.IIa), double dose; 0.2ml (G.IIb) and two single doses 2 weeks apart (G.IIc). Four weeks later, all mice were challenged with S. mansoni cercariae and sacrificed 10 weeks post infection (P.I.). The results revealed that the vaccine in a single dose (G.IIa) induced a high level of protection against S. mansoni infection. There was a significant reduction in the mean number of adult worm (91.12%), ova/gram liver (91.87%), ova/gram intestine (89.09%) and number & size of granulomas in liver (92.92% & 43.53% respectively). Besides, ACV induced a significant increase in the level of IL-10 mRNA expression as compared to the control group.

Food additives and Hymenolepis nana infection: an experimental study.

The effect of sodium benzoate (SB) on the pathogenesis of Hymenolepis nana (H. nana) and its neurological manifestations was studied in the present work. One hundred and thirty five mice were classified into three groups. GI: received SB alone. GII: received SB before & after infection with H. nana and GIII: infected with H. nana. All groups were subjected to parasitological, histopathological, immunohistochemical and biochemical assays. The results revealed a significant decrease in IL-4 serum level with a significant increase in gamma amino butyric acid (GABA) and decrease in zinc brain levels in GI, while GII showed non significant increase in IL-4 level that resulted in a highly significant increase in the mean number of cysticercoids and adult worms with delayed expulsion as compared to GIII. This was reflected on histopathological and immunohistochemical changes in the brain. Also, there was a highly significant increase in GABA and decrease in zinc brain levels in GII to the degree that induced behavioral changes. This emphasizes the possible synergistic effect of SB on the neurological manifestations of H. nana and could, in part, explain the increased incidence of behavioral changes in children exposed to high doses of SB and unfortunately have H. nana infection.

Potential effect of Curcuma longa extract on infectivity and pathogenicity of Schistosoma mansoni cercariae.

Batch of freshly shed cercariae from infected laboratory bred Biomphalaria alexandrina were exposed to different sub-lethal concentrations of turmeric extract for an hour and divided into two groups. The first one was to study the ultrastructural changes induced in them using scanning electron microscopy (SEM). The second group was to study infectivity and pathogenicity of the exposed cercariae. One hundred and fifty mice were divided into 5 groups: GI: Infected by normal cercariae and served as controls; GII, GIII, GIV & GV infected by cercariae exposed to 2.5, 5, 7.5 & 10 ppm, respectively. Ten weeks post infection all animals were sacrificed and subjected to parasitologic, histopathologic and immunologic assays. SEM showed cercariae exposed to 5 ppm with minimal destruction of head spines and tail. The degenerative changes were progressively severe by increasing extract concentration to reach complete destruction of both at 10 ppm. Infectivity decreased with the increase in concentration to reach highest significance at 10 ppm. Pathogenicity or mean number of egg deposited, mean diameter of liver granulomas and level of IL-10 gene expression significantly decreased in Gs IV & V.

Effect of organochlorine (DDT) exposure on experimental giardiasis.

This work studied the effect of sub-chronic DDT exposure on the course of experimental giardiasis and efficacy of its treatment. A total of 160 mice were divided into six groups: G1: 30 mice received DDT and infected with Giardia lamblia. G2: 30 mice received DDT, infected and treated with tinidazole (TNZ). G3: 30 mice infected with Giardia. G4: 30 mice infected and treated with TNZ. G5: 30 mice received DDT only. G6: 10 mice served as normal control. Mice were sacrificed at 7, 14, 21 & 28 days P.I. All groups were subjected to cyst count/2 hours collected stool, trophozoite count in intestine, histopathological examination of small intestinal section and avidin biotin peroxidase technique for local IgA staining. Also, IFN-gamma was measured in sera. DDT caused early shedding of many cysts and increase in trophozoite counts for a long time, decreased intra epithelial lymphocytes, low levels of IgA & IFN-gamma and severe histopathological changes in intestinal sections in G1 as compared to G3. Also, DDT reduced the efficacy of TNZ treatment in G2 as compared to G4. The results strongly support the immunomodulating effect of DDT on experimental giardiasis that might be responsible for persistence of infection, resistance to treatment and re-infection in DDT exposed persons.

Genetic polymorphism of glutathione-S-transferase (GST-M1 and GST-T1) in schistosomiasis -associated bladder cancer in Egyptian patients.

This work was carried out on three groups, 30 Egyptian patients with Schistosoma haematobium (S. haematobium) with bladder cancer (15), and without bladder cancer (15), as well as 15 normal individuals as a control. All the individuals were subjected to measurement of serum level of GST by using ELISA technique and genotyping for GST-M1 & GST-T1 using PCR technique. The results proved that GST serum level was significantly deceased in S. haematobium patients with bladder cancer as compared to the other groups. The PCR results for the GST-M1 & GST-T1 genotyping showed 4 categories, (M1+ve/T1+ve, M1+ve/T1-ve, M1-ve/T1+ve, M1-ve/T1/-ve). There was a significant decrease in enzyme levels in patients with GST-M1-ve/T1-ve as compared to the other categories. Besides, there was a significant increased risk for bladder cancer development in patients with combined gene deletion (OR = 40) which represented mainly in S. haematobium patients with bladder cancer (53.3% = M1-ve/TI-ve).