Hymenolepis diminuta: Activity of anti-oxidant enzymes in different parts of rat gastrointestinal tract

Partial Replacement of Fishmeal with Poultry By-Product Meal in Diets for Coho Salmon (Oncorhynchus kisutch) Post-Smolts

The present study evaluated the effects of partially substituting fish meal (FM) with poultry by-product meal (PBPM) on the growth, muscle composition, and tissue biochemical parameters of coho salmon (Oncorhynchus kisutch) post-smolts. Five isonitrogenous (7.45% nitrogen) and isoenergetic (18.61 MJ/kg gross energy) experimental diets were made by substituting 0%, 10%, 20%, 40%, and 60% FM protein with PBPM protein, which were designated accordingly as PBPM0 (the control), PBPM10, PBPM20, PBPM40, and PBPM60, respectively. Each diet was fed to triplicates of ten post-smolts (initial individual body weight, 180.13 ± 1.32 g) in three floating cages three times daily (6:50, 11:50, and 16:50) to apparent satiation for 84 days. Both specific growth rate (SGR) and protein efficiency ratio did not differ significantly (p > 0.05) among the control, PBPM10, and PBPM20 groups, which were remarkably (p < 0.05) higher than those of the PBPM40 and PBPM60 groups. Feed conversion ratio varied inversely with SGR. The PBPM replacement had no remarkable effects on the morphological indices and proximal muscle components. The control and PBPM10 groups led to significantly higher muscle contents of leucine, lysine, and methionine than groups of higher PBPM inclusion. The groups of PBPM40 and PBPM60 obtained significantly (p < 0.05) higher serum alanine aminotransferase and aspartate aminotransferase activities than the control and low PBPM inclusion groups. The control group had significantly higher albumin and total cholesterol contents than the groups with PBPM inclusion. The control group had significantly higher triglycerides content than the PBPM60 group. The PBPM60 group had significantly lower contents of high-density lipoprotein, low-density lipoprotein, and total protein than the control and PBPM10 groups. The high PBPM replacement level up to 40% and 60% had adverse effects on hepatic malondialdehyde levels. The catalase and superoxide dismutase activities were not affected by low PBPM inclusion, but significantly decreased in high-PBPM-inclusion groups. Based on broken-line regression analysis of SGR and PER, the optimum dietary PBPM replacing level was evaluated to be 16.63-17.50% of FM protein for coho salmon post-smolts.

The Tapeworm Hymenolepis diminuta as an Important Model Organism in the Experimental Parasitology of the 21st Century

The tapeworm Hymenolepis diminuta is a common parasite of the small intestine in rodents but it can also infect humans. Due to its characteristics and ease of maintenance in the laboratory, H. diminuta is also an important model species in studies of cestodiasis, including the search for new drugs, treatments, diagnostics and biochemical processes, as well as its host-parasite interrelationships. A great deal of attention has been devoted to the immune response caused by H. diminuta in the host, and several studies indicate that infection with H. diminuta can reduce the severity of concomitant disease. Here, we present a critical review of the experimental research conducted with the use of H. diminuta as a model organism for over more than two decades (in the 21st century). The present review evaluates the tapeworm H. diminuta as a model organism for studying the molecular biology, biochemistry and immunology aspects of parasitology, as well as certain clinical applications. It also systematizes the latest research on this species. Its findings may contribute to a better understanding of the biology of tapeworms and their adaptation to parasitism, including complex correlations between H. diminuta and invertebrate and vertebrate hosts. It places particular emphasis on its value for the further development of modern experimental parasitology.

Effects of Dietary Riboflavin Supplementation on the Growth Performance, Body Composition and Anti-Oxidative Capacity of Coho Salmon (Oncorhynchus kisutch) Post-Smolts

The present study investigated the effects of dietary riboflavin on growth performance, body composition and anti-oxidative capacity of coho salmon (Oncorhynchus kisutch) post-smolts. Seven experimental diets were formulated with graded riboflavin levels of 0.00, 3.96, 8.07, 16.11, 31.81, 63.67 and 126.69 mg/kg, respectively. Each diet was fed to triplicate groups of 10 fish with an individually initial mean body weight of 186.22 ± 0.41 g in 21 cages (water volume, 1000-L/cage) and fed three times daily (7:30, 12:30 and 17:30) to apparent satiation for 12 weeks. Fish fed a diet with 31.81 mg/kg riboflavin had the highest specific growth rate (SGR), which was significantly higher than fish-fed diets with 0.00, 3.96, 8.07 and 126.69 mg/kg riboflavin (p < 0.05). Feed conversion ratio showed an inverse trend with SGR. No significant differences were observed in condition factor, hepatosomatic index, viscerosomatic index, muscle moisture, crude protein and ash contents among dietary groups. Muscle lipid had the highest content in the 31.81 mg/kg group and was significantly higher (p < 0.05) than those in the 0.00, 3.96 and 8.07 mg/kg groups. The alanine aminotransferase, aspartate aminotransferase and malondialdehyde contents in the liver and serum of fish were significantly decreased with the increase in dietary riboflavin level up to 31.81 mg/kg, and then increased as dietary riboflavin level further increased. An inverse trend was observed for total superoxide dismutase and catalase activities. Serum total cholesterol and triglyceride levels were significantly decreased with the dietary of riboflavin levels up to 31.81 and 63.67 mg/kg, respectively. The cubic curve regression analysis based on SGR indicated that the optimum dietary riboflavin level was estimated to be 35.26 mg/kg for coho salmon post-smolts.

Histopathological and biochemical studies on immunocompetent and immunocompromised Hymenolepis nana infected mice treated with Commiphora molmol (Mirazid)

Hymenolepiasis is a common parasitic infection of children and considered an opportunistic disease with a life-threatening effect among immunocompromised patients through cysticercoid dissemination. Mirazid (Commiphora molmol) is new phytotherapy for hymenolepiasis. So, the present study aimed to evaluate the effects of Mirazid treatment comparing to Praziquantel (PZQ) (standard treatment) among immunocompetent and immunocompromised infected albino mice through biochemical and histopathological parameters. A total of 60 clean male albino mice (immunocompetent group) were divided into equal five groups which were infected and treated with Mirazid beside PZQ. Another 72 infected immunocompromised animals were divided into equal six groups and were also treated with Mirazid and PZQ. Liver and kidney functions were estimated as well as histopathological examination of intestine and liver. Levels of AST in the serum of infected mice treated with Mirazid or PZQ recorded a highly significant increase compared to the normal control group. The percentage of increase was 83.30% and 36.60% respectively. While the infected group recorded a non-significant decrease in AST level and the percentage of decrease was - 7.4%. Immunocompetent groups showed a positive significant correlation with the control Mirazid or control PZQ groups recorded an increase in liver function enzymes (AST, Bilirubin, and GGT) (P < 0.001) comparing to the normal control group. In conclusion, Mirazid showed higher cure rates than PZQ, 95.45%, and 74.54% on the 15th and the 21st days, it reached 100% respectively associated with good improvement of histopathological changes in intestine and liver.

In vitro anthelmintic activity of Psidium guajava hydroalcoholic extract against gastro-intestinal sheep nematodes

Tanniferous plants have been used for ruminants verminosis control and represent a possibility to minimize the pharmacological resistance against conventional antiparasitics. This study aimed to evaluate the antihelminthic activity of the hydroalcoholic extract of stem bark of guava tree (PgHA). It was performed the hatchability and larval migration inhibition assays to evaluate PgHA at the following concentrations 0.62, 1.25, 2.5 and 5.0 mg mL-1 and the control treatments. The total polyphenol, flavonoid and tannin contents were determined by phytochemical analysis, high performance liquid chromatography coupled to mass spectrometry. The antioxidant activity was evaluated by 1,1-diphenyl-2-picrylhydrazyl, ferric reducing antioxidant power and thiobarbituric acid reactive substances tests. It was also determinated total protein, intracellular H2O2 and antioxidant activity of enzimes: glutathione S-transferase and superoxide dismutase. PgHA was able to inhibit both hatchability and larval migration, but only hatchability inhibition presented dose-dependent pattern. The antioxidant activity was demonstrated by linear regression with IC50 corresponding to 534.02 μg mL-1. The antiparasitic mechanism occurred through pro-oxidative activity by the increase of total proteins, intracellular H2O2 and the lipid peroxidation products, as well as the increase of the enzymes above related. Thus, the PgHA showed antiparasitic activity in vitro.

Antioxidant defense in the eyes of immunocompetent and immunosuppressed mice infected with Acanthamoeba spp

Background

Acanthamoeba spp. are ubiquitous pathogens which cause granulomatous amoebic encephalitis and disseminated infection. Moreover, Acanthamoeba spp. infection of the cornea leads to Acanthamoeba keratitis. Our previous study showed that the infection of an eyeball may also take place via the migration of trophozoites through the optic nerve from the brain to the eyes. The aim of the study was to analyze the activity of enzymatic antioxidants and the concentration of non-enzymatic antioxidant in the eyes of immunocompetent and immunocompromised mice with disseminated acanthamoebiasis.

Results

In the immunocompetent mice infected with Acanthamoeba spp. we noted a significant decrease in catalase activity at 8 and 16 days post-infection (dpi). Glutathione reductase activity was significantly lower at 16 dpi compared to the control group and glutathione concentration was statistically higher at 24 dpi than in the control group. In the immunosuppressed mice, a statistically significant increase in glutathione concentration in the eye samples was found at 16 dpi compared to those not infected with Acanthamoeba spp. In the immunosuppressed mice infected with Acanthamoeba spp., glutathione peroxidase activity was statistically lower at 8 dpi, and glutathione concentration was statistically significantly higher at 16 dpi compared to the control group.

Conclusions

The inflammatory response in the eyes of hosts with experimental acanthamoebiasis led to changes in the activity of enzymatic antioxidants and the content of non-enzymatic antioxidant. Therefore, the dysregulation of antioxidants may play a role in the pathomechanism of Acanthamoeba eye infection.

The Comparison of Parameters of Oxidative Stress in Native Rat Livers Between Different Immunosuppressive Regimens

Background

It is thought that immunosuppressive treatment, besides anti-rejection properties, leads to pathological changes within the organ due to activation of mechanisms associated with oxidative stress. The aim of this study was to examine the parameters of oxidative stress in the livers of rats treated with the most commonly used transplant recipient drug regimens.

Material/Methods

The rat livers were obtained from archival material obtained from the previously performed experiment. Malondialdehyde (MDA), reduced glutathione (GSH) concentrations, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities were analyzed.

Results

Only the group treated with tacrolimus (T), mycophenolate mofetil (M), and prednisone (P), the TMP group, showed a slight increase in lipid peroxide concentration compared to the control group, though the difference was not statistically significant. Comparison of lipid peroxide concentration between the other treatment combinations and the control group showed a significant decrease. Additionally, a difference in lipid peroxide concentrations in the livers was observed between the cyclosporine A (C) group and tacrolimus (T) group. Alterations of other oxidative stress parameters were also observed in different regimens.

Conclusions

Long-lasting immunosuppressive treatment does indeed affect redox status; however, the antioxidant defenses of the liver against the effects of excess hydrogen peroxide are efficient, so the superoxide dismutase/glutathione peroxidase (SOD/GPx) and superoxide dismutase/catalase (SOD/CAT) ratios were not significant.

Immunoproteomics and Surfaceomics of the Adult Tapeworm Hymenolepis diminuta

In cestodiasis, mechanical and molecular contact between the parasite and the host activates the immune response of the host and may result in inflammatory processes, leading to ulceration and intestinal dysfunctions. The aim of the present study was to identify antigenic proteins of the adult cestode Hymenolepis diminuta by subjecting the total protein extracts from adult tapeworms to 2DE immunoblotting (two-dimensional electrophoresis combined with immunoblotting) using sera collected from experimentally infected rats. A total of 36 protein spots cross-reacting with the rat sera were identified using LC-MS/MS. As a result, 68 proteins, including certain structural muscle proteins (actin, myosin, and paramyosin) and moonlighters (heat shock proteins, kinases, phosphatases, and glycolytic enzymes) were identified; most of these were predicted to possess binding and/or catalytic activity required in various metabolic and cellular processes, and reported here as potential antigens of the adult cestode for the first time. As several of these antigens can also be found at the cell surface, the surface-associated proteins were extracted and subjected to in-solution digestion for LC-MS/MS identification (surfaceomics). As a result, a total of 76 proteins were identified, from which 31 proteins, based on 2DE immunoblotting, were predicted to be immunogenic. These included structural proteins actin, myosin and tubulin as well as certain moonlighting proteins (heat-shock chaperones) while enzymes with diverse catalytic activities were found as the most dominating group of proteins. In conclusion, the present study shed new light into the complexity of the enteric cestodiasis by showing that the H. diminuta somatic proteins exposed to the host possess immunomodulatory functions, and that the immune response of the host could be stimulated by diverse mechanisms, involving also those triggering protein export via yet unknown pathways.

Relationship between antioxidant defense in Acanthamoeba spp. infected lungs and host immunological status

The role of oxidative stress in the pathogenicity of acanthamoebiasis is an important aspect of the intricate and complex host-parasite relationship. The aim of this experimental study was to determine oxidative stress through the assessment of lipid peroxidation product (LPO) levels and antioxidant defense mechanism in Acanthamoeba spp. lung infections in immunocompetent and immunosuppressed hosts. In Acanthamoeba spp. infected immunocompetent mice we noted a significant increase in lung lipid peroxidation products (LPO) at 8 days and 16 days post infection (dpi). There was a significant upregulation in lung LPO in immunocompetent and immunosuppressed mice infected by Acanthamoeba spp. at 16 dpi. The superoxide dismutase activity decreased significantly in lungs in immunosuppressed mice at 8 dpi. The catalase activity was significantly upregulated in lungs in immunocompetent vs. immunosuppressed group and in immunocompetent vs. control mice at 16 dpi. The glutathione reductase activity was significantly lower in immunosuppressed group vs. immunosuppressed control at 24 dpi. We found significant glutathione peroxidase downregulation in immunocompetent and immunosuppressed groups vs. controls at 8 dpi, and in immunosuppressed vs. immunosuppressed control at 16 dpi. The consequence of the inflammatory response in immunocompetent and immunosuppressed hosts in the course of experimental Acanthamoeba spp. infection was the reduction of the antioxidant capacity of the lungs resulting from changes in the activity of antioxidant enzymes. Therefore, the imbalance between oxidant and antioxidant processes may play a major role in pathology associated with Acanthamoeba pneumonia.

Selected Molecular Mechanisms Involved in the Parasite⁻Host System Hymenolepis diminuta⁻Rattus norvegicus

The rat tapeworm Hymenolepis diminuta is a parasite of the small intestine of rodents (mainly mice and rats), and accidentally humans. It is classified as a non-invasive tapeworm due to the lack of hooks on the tapeworm’s scolex, which could cause mechanical damage to host tissues. However, many studies have shown that metabolites secreted by H. diminuta interfere with the functioning of the host’s gastrointestinal tract, causing an increase in salivary secretion, suppression of gastric acid secretion, and an increase in the trypsin activity in the duodenum chyme. Our work presents the biochemical and molecular mechanisms of a parasite-host interaction, including the influence on ion transport and host intestinal microflora, morphology and biochemical parameters of blood, secretion of antioxidant enzymes, expression of Toll-like receptors, mechanisms of immune response, as well as the expression and activity of cyclooxygenases. We emphasize the interrelations between the parasite and the host at the cellular level resulting from the direct impact of the parasite as well as host defense reactions that lead to changes in the host’s tissues and organs.

The inflammatory effect of infection with Hymenolepis diminuta via the increased expression and activity of COX-1 and COX-2 in the rat jejunum and colon

The aim of this study was to determine whether Hymenolepis diminuta may affect the expression and activity of cyclooxygenase 1 (COX-1) and cyclooxygenase 2 (COX-2), resulting in the altered levels of their main products - prostaglandins (PGE2) and thromboxane B2 (TXB2). The study used the same experimental model as in our previous studies in which we had observed changes in the transepithelial ion transport, tight junctions and in the indicators of oxidative stress, in both small and large intestines of rats infected with H. diminuta. In this paper, we investigated not only the site of immediate presence of the tapeworm (jejunum), but also a distant site (colon). Inflammation related to H. diminuta infection is associated with the increased expression and activation of cyclooxygenase (COX), enzyme responsible for the synthesis of PGE2 and TXB2, local hormones contributing to the enhanced inflammatory reaction in the jejunum and colon in the infected rats. The increased COX expression and activity is probably caused by the increased levels of free radicals and the weakening of the host's antioxidant defense induced by the presence of the parasite. Our immunohistochemical analysis showed that H. diminuta infection affected not only the intensity of the immunodetection of COX but also the enzyme protein localization within intestinal epithelial cells - from the entire cytoplasm to apical/basal regions of cells, or even to the nucleus.

Hymenolepis diminuta: analysis of the expression of Toll-like receptor genes and protein (TLR3 and TLR9) in the small and large intestines of rats

Toll-like receptors (TLRs) play a fundamental role in the rapid activation of innate immune responses to a variety of pathogen-associated molecular patterns (PAMPs). In a previous study we observed an increase in the level of expression of TLR2 and TLR4 mRNA in the jejunum and colon during experimental hymenolepidosis in rats. In this study, we performed a quantitative real-time polymerase chain reaction (qRT-PCR), Western blot analysis and immunohistochemical staining of TLR3 and TLR9 receptors during experimental hymenolepidosis in rats. The levels of mRNA and protein expression of TLR3 and TLR9 in the jejunum had increased at 16 days post Hymenolepis diminuta infection (dpi) in the case of TLR3 and at 16 and 25 dpi in the case of TLR9. In the colon the expression of TLR3 and TLR9 had increased at 16, 25 and 40 dpi. The results of the immunohistochemical reactions showed that H. diminuta infected rats (16, 25, 40 and 60 dpi) exhibited changes in TLR3 and TLR9 localization and intensity in the epithelial cells of the jejunum and colon. The changes in the level of TLR3 and TLR9 expression may confirm involvement of the innate immune system in the pathomechanism of hymenolepidosis.

Effects of dietary copper on growth, digestive, and brush border enzyme activities and antioxidant defense of hepatopancreas and intestine for young grass carp (Ctenopharyngodon idella)

To investigate the effects of dietary copper (Cu) on fish growth, digestive and absorptive enzyme activities, and antioxidant status in the hepatopancreas and intestine, young grass carp (Ctenopharyngodon idella) (282±2.8 g) were fed six diets containing 0.74 (basal diet), 2.26, 3.75, 5.25, 6.70, and 8.33 mg Cu /kg diet for 8 weeks. Results showed that percentage weight gain (PWG) and feed intake were increased with dietary Cu levels up to 3.75 mg/kg diet. In addition, the positive effects of dietary Cu at a level 3.75 or 5.25 mg/kg diet on trypsin, chymotrypsin, and lipase activities in the hepatopancreas and of Na(+), K(+)-ATPase, alkaline phosphatase, creatine kinase, and γ-glutamyl transpeptidase activities in three intestine segments produced significantly (P<0.05) better feed efficiency (FE). However, amylase activity in the hepatopancreas was decreased by dietary Cu levels up to 3.75 mg/kg diet (P<0.05). In addition, dietary Cu at 3.75 or 5.25 mg/kg diet decreased malondialdehyde and protein carbonyl content partly by significantly (P<0.05) increasing the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and glutathione content in the hepatopancreas and intestine. Collectively, dietary Cu improved growth and digestive and absorptive capacity and decreased lipid peroxidation and protein oxidation partly by enhancing antioxidant defense in the hepatopancreas and intestine. The dietary Cu requirement for PWG, plasma ceruloplasmin activity, and FE of young grass carp (282-688 g) were 4.78, 4.95, and 4.70 mg/kg diet, respectively.

Hymenolepis diminuta: analysis of the expression of Toll-like receptor genes (TLR2 and TLR4) in the small and large intestines of rats. Part II

Toll-like receptors in the gastrointestinal tract can influence intestinal homeostasis and play a role in the repair and restitution of intestinal epithelium following tissue damage. In our previous study a statistically significant increase in the level of TLR4 and TLR2 gene expression was observed in rats in early stages of hymenolepidosis. Moreover, the immunopositive cell number and the intensity of immunohistochemical staining (indicating the presence of TLRs within intestinal epithelial cells) increased over the infection period. In this paper, we determined changes in the expression of TLR2 and TLR4 and the number of anaerobic intestinal commensal bacteria in Hymenolepis diminuta infected rats. In the isolated jejunum of infected rats at 16 days post infection (dpi), the expression of TLR4 and TLR2 was significantly higher than uninfected rats. In the colon, a statistically significantly increased expression of TLR2 was observed from 16 to 40 dpi, and TLR4 from 16 to 60 dpi. The jejunum and colon of infected rats contained Gram-negative bacteria (Escherichia coli), Gram-positive bacteria (Enterococcus, Streptococcus, Staphylococcus, Bacillus, Lactobacillus) and Candida. The total number of intestinal bacteria was higher in H. diminuta infected rats, but the observed microbiota had only minor effects on the expression of TLR2 and TLR4. Toll-like receptors play a role in maintaining epithelial barrier function in response to enteric pathogens and parasites. In our study, the alteration of TLR2 and TLR4 expression in the infected rats indicates the potential role of the innate immune system in the pathomechanism of this infection.

Hymenolepis diminuta: analysis of the expression of Toll-like receptor genes (TLR2 and TLR4) in the small and large intestines of rats

Toll receptors play a critical role in the rapid activation of innate immune responses to a variety of pathogens. In mammals, Toll-like receptors (TLR) have been found in both immune related cells and other cells. At present little is known about the participation of TLR in host defense mechanisms during parasitic infections. The aim of this study was to determine the expression of TLR2 and TLR4 genes in rat intestines during experimental hymenolepidosis. There is difference in expression of TLR2 and TLR4 genes in the colon and jejunum in uninfected rats: in the colon, mRNA of the examined TLR is present in much higher amounts than the jejunum, while the protein of the TLR also had a segmented specific distribution. In the jejunum isolated rats infected with Hymeolepis diminuta 6 and 8 days post infection (dpi), mRNA for TLR4 and TLR2 were significantly more strongly expressed in comparison with the uninfected controls. In the colon, a statistically significantly increased expression of TLR4 gene was observed only at 6 dpi, and at 8 dpi for the TLR2 gene. Moreover, we observed that during inflammation, the immunopositive cell number and the intensity of immunohistochemical staining (indicating the presence of TLR within intestinal epithelial cells), increased together with the duration of the infection period.