Effects of tannic acid on Haemonchus contortus larvae viability and immune responses of sheep white blood cells in vitro

Role of hazelnut skin supplementation on plasma antioxidant status and cytokine profile in growing lambs

In this study, the effect of hazelnut skin dietary supplementation on antioxidant status and cytokine profile was evaluated in growing lambs. A total of 22 male lambs at the age of 2 months, balanced for their initial live weight (15.33 ± SD 1.79 kg), were selected and allocated into two experimental groups: the control group (CON) receiving a maize-barley-based concentrated diet, and the hazelnut group (HS) receiving supplementation with hazelnut skin (150 g/kg on the dry matter) as a maize substitute for the concentrate diet. The experiment lasted for 56 days. Peripheral blood was collected at 7, 35, and 56 days of the experiment. The free radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, the total antioxidant capacity assay (TAC), the reactive oxygen species (ROS), and reactive nitrogen species (RNS) were determined in plasma. The secretion of IL-1β, IL-6, and IL-10 cytokines was also determined by ELISA. The DPPH was affected by the interaction between feeding strategy and time of sampling (p = 0.039) with a higher level of DPPH at 7 days in the HS group than the CON group. The time of sampling affected the levels of plasma TAC (p = 0.016), while the ROS/RNS levels showed a higher value in the HS group (p < 0.001), on average. The antioxidant/oxidant index, which combines the TAC and the ROS/RNS levels, was not affected by the inclusion of hazelnut skin in the diet (p = 0.394). The cytokine profile showed a lower IL-6 secretion at both 35 and 56 days than at 7 days, on average. Furthermore, the feeding treatment affected the IL-1β level, showing a lower level in the HS group than in the CON group on average. Lambs from the HS group had higher IL-10 plasma levels than the CON group at 7 days of the experiment. The present data highlight an antioxidant effect and a modulatory role in the cytokine profile of HS supplementation in growing lambs.

Characterization of a novel pyruvate kinase from Trichinella spiralis and its participation in sugar metabolism, larval molting and development

Background

Pyruvate kinase widely exists in many parasites and plays an important role in the energy production for the parasites. Pyruvate kinase might be a potential drug target for killing the parasites. The aim of the present study was to evaluate the biological characteristics and roles of T. spiralis pyruvate kinase M (TsPKM) in sugar metabolism, larval molting and development of T. spiralis.

Methodology/Principal findings

TsPKM has two functional domains of pyruvate kinase and the tertiary structure of TsPKM is tetramer which has the enzyme active site constituted by 8 amino-acid residues (Arg71, Asn73, Asp110, Phe241, Lys267, Glu269, Asp293 and Thr325). Recombinant TsPKM (rTsPKM) was expressed and purified. The rTsPKM had good immunogenicity. RT-PCR and Western blot showed that TsPKM was transcribed and expressed at various developmental stages in T. spiralis lifecycle. Immunofluorescence test showed that TsPKM was principally located in the cuticle, muscle, stichosome, intestine and the intrauterine embryos of female adults. rTsPKM catalyzed the reaction of phosphoenolpyruvate (PEP) and adenosine diphosphate (ADP) to produce pyruvic acid and adenosine triphosphate (ATP). TsPKM played an important role in the metabolism and energy production of T. spiralis. After silencing of TsPKM gene by specific dsRNA-TsPKM2, protein expression and enzyme activity of TsPKM decreased by 50.91 and 26.06%, respectively. After treatment with RNAi, natural TsPKM enzyme activity, larval molting, sugar metabolism, growth and development of T. spiralis were significantly reduced.

Conclusions

TsPKM participates in the larval molting, sugar metabolism, growth and development of T. spiralis and it might be a candidate target of therapeutic drug of trichinellosis.

Pyruvate kinases belong to transferases and can transfer the high-energy phosphate bond of phosphoenolpyruvate (PEP) to adenosine diphosphate (ADP) to produce pyruvic acid and adenosine triphosphate (ATP). Pyruvate kinases play a significant biological role in the parasite survival in hosts. Our results revealed that TsPKM was expressed at various T. spiralis developmental stages, and principally located in the cuticle, stichosome, intestine and the intrauterine embryos of female adults. rTsPKM catalyzed the reaction of phosphoenolpyruvate (PEP) and adenosine diphosphate (ADP) to produce pyruvic acid and adenosine triphosphate (ATP). TsPKM played an important role in the metabolism and energy production of T. spiralis. Protein expression and enzyme activity of TsPKM were decreased by 50.91 and 26.06% respectively through silencing of TsPKM gene using specific dsRNA-TsPKM2. After treatment with RNAi and inhibitor tannin, natural TsPKM activity, larval molting, sugar metabolism, growth and development of T. spiralis were obviously inhibited. Our results showed that TsPKM participates in T. spiralis molting, sugar metabolism and development, and it might be a candidate target for anti-Trichinella drugs.

Pharmacological effects and mechanisms of tannic acid

In recent years, increasing attention has been paid to the pharmacological efficacy of tannins. Tannic acid (TA), the simplest hydrolysable tannin that has been approved by the FDA as a safe food additive, is one of the most important components of these traditional medicines. Studies have shown that TA displays a wide range of pharmacological activities, such as anti-inflammatory, neuroprotective, antitumor, cardioprotective, and anti-pathogenic effects. Here, we summarize the known pharmacological effects and associated mechanisms of TA. We focus on the effect and mechanism of TA in various animal models of inflammatory disease and organ, brain, and cardiovascular injury. Moreover, we discuss the possible molecular targets and signaling pathways of TA, in addition to the pharmacological effects of TA-based nanoparticles and TA in combination with chemotherapeutic drugs.

Anthelmintic effect of Indigofera tinctoria L on Haemonchus contortus obtained from sheep in Indonesia

Background and Aim:

Hemonchosis has resulted in huge economic losses for sheep farmers worldwide. Secondary metabolite compounds from Indigofera tinctoria L. can be used as anthelmintics. This study aimed to evaluate the in vitro and in vivo effects of I. tinctoria L. aqueous extract (IAE) as an anthelmintic against adult Haemonchus contortus isolated from sheep.

Materials and Methods:

Ten active adult worms were placed in each Petri dish containing 25 mL of IAE, each having a different concentration of IAE (at concentrations 100, 120, 140, 160, 180, 200, and 220 mg/mL). Each experiment was repeated. The positive control used 1% albendazole, and the negative control used 0.62% saline water. The number of immobile worms and the time of mortality were recorded after 2, 4, 6, and 8 h. The dead worms were subsequently tested using scanning electron microscopy (SEM) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In the in vivo study, 15 sheep with an average fecal egg count (FEC) of 1000 eggs per gram were treated with IAE for 9 days: Group A (negative control, saline water 0.62%), Group B (21 mg/mL), Group C (41 mg/mL), Group D (62 mg/mL), and Group E (positive control, albendazole 100 mg/mL). Measurements of the body weight, FEC reduction test, and hematology testing were performed on days 0, 7, and 14. SEM was performed using worms found from the abomasum of slaughtered sheep.

Results:

The leaves of I. tinctoria L. contained a number of secondary metabolites, including total tannins, saponins, flavonoids, and alkaloids. The most effective concentration that killed the adult H. contortus worms was 220 mg/mL (93.33% mortality) after 8 h of treatment. The electrophoresis results showed that the protein band at a dose of 22% was less than that of the control. The highest FECR value of the treatment group on the 14^th day after treatment was at a dose of 62 mg/mL. The highest weight gain as well as the highest increased hemoglobin (Hb), packed cell volume (PCV), and total erythrocyte count (TEC) values on the 14^th day after treatment were at a dose of 41 mg/mL. The SEM results showed that IAE treatment caused the worms’ anterior parts to become wrinkled with thick creases and cuticle abrasion (in vitro) and the anterior part to shrink along with the presence of aggregates in the worm cuticle (in vivo).

Conclusion:

The aqueous extract of I. tinctoria contains tannins, saponins, flavonoids, and alkaloids and has an anthelmintic effect with decreased FEC, increased weight gain, Hb, PCV, and TEC, causing damage to the worms’ body and reducing the protein profile of adult H. contortus worms.

Effects of chestnut tannins supplementation of prepartum moderate yielding dairy cows on metabolic health, antioxidant and colostrum indices

This study investigated the effects of dietary supplementation with chestnut tannins (CNT) on metabolic and antioxidant status of prepartum cows along with their colostrum quality. Pregnant multiparous Holstein cows were paired according to parity and body condition score, and assigned either to a diet supplemented with 20 g/d of commercially available product containing chestnut tannins (CNT, n=20) or to an unsupplemented control diet (CON, n=20) for the last 25±2 d of pregnancy. Serum metabolite, insulin and antioxidant capacity indices were measured in blood samples taken at d 25 and d 5 before expected parturition. Chemical composition and IgG concentration were determined in colostrum samples collected from the first milking postpartum. The addition of CNT led to lower BUN (P=0.02) and consequently higher serum glucose (P=0.02) and insulin (P<0.01) concentrations which were associated with lower circulating NEFA (P<0.01) and BHBA (P<0.01) in CNT group than those of CON. The serum paraoxonase 1 (PON 1) activity and total antioxidant capacity (TAOC) were higher at -5 d in CNT than in CON (P<0.01, P=0.03; respectively). Close-up CNT improved lactose percentage and IgG concentration (P=0.03, P=0.04; respectively) and tended to improve percentage of protein and SNF (Solid Not Fat) in primary colostrum (P=0.06, respectively), without affecting colostrum fat and total solid (P=0.98, P=0.43; respectively). Supplementation of CNT in the diet during close-up period did not have adverse effects on metabolic profiles prepartum. Instead, this feeding regimen was more beneficial to antioxidant capacity and colostrum quality than feeding the control diet.

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.

In vitro and in vivo Areca catechu crude aqueous extract as an anthelmintic against Ascaridia galli infection in chickens

Aim:

Intestinal parasites cause severe diseases at poultry farms, especially in developing countries, including Indonesia. Infections cause significant decreases in productivity at poultry farms. Ascaridia galli is a common nematode found in chickens with a prevalence of up to 92%. This study evaluates the in vitro and in vivo effects of Areca catechu crude aqueous extract (AAE) as an anthelmintic against A. galli.

Materials and Methods:

In the in vitro study, already-infected slaughtered chickens were collected from local slaughterhouses in Yogyakarta. The chicken intestines were carefully examined and transported to the Parasitological Laboratory of Gadjah Mada University, Yogyakarta. A. galli was collected from the intestines and put into a Petri dish containing 0.62% saline solution. Sixty A. galli individuals were soaked in different concentrations of the AAE for 3-6 h. The number of deceased A. galli was recorded by ascertaining whether they had ceased movement using a stereo microscope. The morphological characteristics of the parasites were studied. The in vivo study used 40 female chickens that were 1.5 months old and infected with the eggs of A. galli. Approximately 3000 infective eggs were found in each chicken. There were four treatment groups; Group A served as the control and was treated with Aquadestilata, Group B was treated with 26 mg/ml of AAE, Group C was treated with 79 mg/ml of AAE, and Group D was treated with 50 mg/ml of pyrantel pamoate. The AAE was applied using a pipette for 14 days. The observed parameters include the effect of the treatments on hematology, body weight (BW), and the number of A. galli eggs within each gram of fecal matter.

Results:

The AAE damaged the morphology, including the anterior end, posterior end, and vulva, of A. galli in vitro. The tegument of the anterior and posterior ends was slightly rougher, wrinkled, and damaged. The vulva and spicule ducts were irregular and indistinct. The average eggs per gram (EPG) in the untreated control increased in vivo from 1450±355.90 to 1975±325.96. The average EPG decreased from 1485±386.62 to 0±0.00 during 14 days of treatment of 79 mg/ml of AAE. The mean BW gain in the treated chickens was significantly (p<0.5) higher than the control. The treatment with 79 mg/ml of AAE increased the total erythrocyte count, total leukocyte count, hemoglobin, and packed cell volume values in the chickens.

Conclusion:

AAE can cause morphological changes and subsequent death in adult A. galliin vitro and effectively decrease ascariasis severity in chickens, therefore increasing overall BW in vivo.

Hepatocellular carcinoma-associated antigen 59 of Haemonchus contortus modulates the functions of PBMCs and the differentiation and maturation of monocyte-derived dendritic cells of goats in vitro

BACKGROUND

Hepatocellular carcinoma-associated antigen 59 (HCA59), which is one of the most important excretory/secretory products of Haemonchus contortus (HcESPs), is known to have antigenic functions. However, its immunomodulatory effects on host cells are poorly understood.

METHODS

Here, we cloned the HCA59 gene and expressed the recombinant protein of HCA59 (rHCA59). Binding activities of rHCA59 to goat peripheral blood mononuclear cells (PBMCs) and dendritic cells (DCs) were checked by immunofluorescence assay (IFA) and the immunoregulatory effects of rHCA59 on cytokine secretions, cell migration, cell proliferation, nitric oxide production, and changes in expression of genes in related pathways were observed by co-incubation of rHCA59 with goat PBMCs and DCs. Monocyte phagocytosis and characterization of goat blood DC subsets were detected by flow cytometry.

RESULTS

The IFA results revealed that rHCA59 could bind to PBMCs and DCs. Treatment of PBMCs with rHCA59 significantly increased cellular proliferation and NO production in a dose-dependent manner, while cell migration was vigorously blocked. Treatment with rHCA59 significantly suppressed monocytes phagocytosis. The quantity of surface marker CD80 on DCs increased significantly after rHCA59 treatment. In addition, the expression of genes included in the WNT pathway was related to the differentiation and maturation of DCs, and the production of IL-10 and IL-17 produced by PBMCs was altered.

CONCLUSIONS

Our findings illustrated that rHCA59 could enhance host immune responses by regulating the functions of goat PBMCs and DCs, which would benefit our understanding of HCA59 from parasitic nematodes contributing to the mechanism of parasitic immune evasion.

Morphology and morphometry of Haemonchus contortus exposed to Gigantochloa apus crude aqueous extract

Aim:

Haemonchus contortus is the most pathogenic nematode infesting the digestive tract of goats and sheep worldwide leading to a tremendous loss in a variety of routes. Economic losses due to haemonchosis in subtropic and tropic areas are usually caused by poor weight gain, minimized growth, loss of production, and mortality. The prevalence of haemonchosis in Indonesia is 89.4% in goat, and annual loss achieved 1 million US dollars. This study evaluated in vitro effects of Gigantochloa apus crude aqueous extract as an anthelmintic on H. contortus morphology and morphometry.

Materials and Methods:

Bligon goats which are naturally infected were collected from slaughtered goat from local slaughterhouses, namely Besi Sleman. Bligon goat’s abomasum part was carefully examined and transported to the Parasitology Laboratory, University of Gadjah Mada, Yogyakarta. H. contortus was obtained from 4 to 6-month-old female goat from slaughterhouses in Yogyakarta area. H. contortus was collected from abomasum and put into a Petri dish containing 0.62% water saline. The number of H. contortus used for each concentration is 25. H. contortus was soaked in each concentration for 4 h. The figure of the parasites or parts of parasites was captured using camera Lucida, and they were measured using both objective micrometer and objective ocular micrometer. All the capturing processes were done with the help of Olympus Digital Camera under Olympus CX21 microscopic. Parasite morphology was identified in morphological and morphometric characters.

Result:

Morphology of H. contortus revealed the cervical papillae bulge appears unclear shape and anterior end is more tapered. Vulvar flab control is not tapered, but vulvar flab which gets aware of G. apus crude aqueous extract looks more pointed. The gubernaculum appears irregular compared to gubernaculum control which tends to be more compact, and the posterior end form appears irregular more than posterior end control. Morphometry study of H. contortus indicates that it has a significant difference for body length, body width, cervical papillae, and spicule length in the male.

Conclusion:

G. apus crude aqueous extract activity revealed morphology change such as cervical papillae, vulvar flab, gubernaculum, posterior end, and reduced morphometry measurement of H. contortus adult worms, notably in body length, body width, cervical papillae width, gubernaculum, and spicule length in males and body length, body width, cervical papillae width, and vulva length in females.

In vitro potential anthelmintic activity of Biophytum petersianum on Haemonchus contortus

Aim:

Haemonchus contortus is a major problem in small ruminants in Indonesia. The frequent use of the anthelmintic drugs has given rise to drug-resistant populations which increase the need for new anthelminthic compounds, particularly from endemic plants. This study evaluated the in vitro effects of Biophytum petersianum crude aqueous extract (BAE) as an anthelmintic compound against H. contortus adult worm isolated from goats.

Materials and Methods:

Adult worm collected from naturally infected abomasums were obtained from slaughtered goats on the day of slaughter. BAE was prepared in six different concentrations (10, 20, 40, 60, 80, and 100 mg/ml) which were tested for their efficacies on ten actively moving worms. Ivermectin (1 mg/ml) was included as a reference drug, while saline water was included as a control. The dead worms from anthelmintic test then went through sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and scanning electron microscopy (SEM).

Results:

Highest mean mortality in treatments group both at 2 h and 4 h observations was BAE 10%. The SDS-PAGE analysis revealed the presence of five protein bands with molecular weights 9.3, 17.1, 50.0, 63.2, and 72.7 kDa based on BAE 10%. The SEM changes observed in the in vitro trials revealed the occurrence of interactions between the BAE and the cuticle.

Conclusion:

The SEM and SDS-PAGE analysis revealed ultrastructural structural changes and the decrease numbers of polypeptides on treated worms when compared to the control worms. It can thus be concluded that the BAE exhibits good anthelmintic activity against H. contortus adult worm.

Co-operative suppression of inflammatory responses in human dendritic cells by plant proanthocyanidins and products from the parasitic nematode Trichuris suis

Interactions between dendritic cells (DCs) and environmental, dietary and pathogen antigens play a key role in immune homeostasis and regulation of inflammation. Dietary polyphenols such as proanthocyanidins (PAC) may reduce inflammation, and we therefore hypothesized that PAC may suppress lipopolysaccharide (LPS) -induced responses in human DCs and subsequent T helper type 1 (Th1) -type responses in naive T cells. Moreover, we proposed that, because DCs are likely to be exposed to multiple stimuli, the activity of PAC may synergise with other bioactive molecules that have anti-inflammatory activity, e.g. soluble products from the helminth parasite Trichuris suis (TsSP). We show that PAC are endocytosed by monocyte-derived DCs and selectively induce CD86 expression. Subsequently, PAC suppress the LPS-induced secretion of interleukin-6 (IL-6) and IL-12p70, while enhancing secretion of IL-10. Incubation of DCs with PAC did not affect lymphocyte proliferation; however, subsequent interferon-γ production was markedly suppressed, while IL-4 production was unaffected. The activity of PAC was confined to oligomers (degree of polymerization ≥ 4). Co-pulsing DCs with TsSP and PAC synergistically reduced secretion of tumour necrosis factor-α, IL-6 and IL-12p70 while increasing IL-10 secretion. Moreover, both TsSP and PAC alone induced Th2-associated OX40L expression in DCs, and together synergized to up-regulate OX40L. These data suggest that PAC induce an anti-inflammatory phenotype in human DCs that selectively down-regulates Th1 response in naive T cells, and that they also act cooperatively with TsSP. Our results indicate a novel interaction between dietary compounds and parasite products to influence immune function, and may suggest that combinations of PAC and TsSP can have therapeutic potential for inflammatory disorders.

Design of enzyme-immobilized polymer brush-grafted magnetic nanoparticles for efficient nematicidal activity

Parasitic nematodes adversely affect agricultural industry and global health. An efficient and reusable nematicidal platform is developed by immobilization enzyme on the surface of magnetic NPs.

Effects of supplementation with dietary green tea polyphenols on parasite resistance and acute phase protein response to Haemonchus contortus infection in lambs

The objective of this study was to determine the effects of supplementation with dietary green tea polyphenols (GTPs) on parasite resistance and acute phase protein (APP) response to Haemonchus contortus infection in lambs. Thirty male Ujumqin lambs were randomly assigned to five treatment groups for an 8-week feeding period. Treatments included: (1) uninfected as control, (2) infected but not given GTP (INFGTP0) and (3)-(5) infected and fed 2, 4, or 6g GTP/kg feed (dry matter basis; INFGTP2, INFGTP4, and INFGTP6, respectively). Fecal and blood samples were collected to determine fecal egg count (FEC), packed cell volume (PCV), and APP concentrations. Live weight was measured once every 2 weeks. At the end of the feeding period, lambs were slaughtered to determine the adult H. contortus burden. The results demonstrated interaction effects between treatment and sampling time on the average daily gain (ADG; P=0.0005), FEC (P<0.0001), PCV (P=0.0005), and concentrations of serum amyloid A (SAA), haptoglobin (Hp), lipopolysaccharide binding protein (LBP), and α1-acid glycoprotein (α1AGP) (P<0.0001). From days 0 to 56, the ADG values for all infected lambs were lower than that of uninfected lambs, but the ADG values for all GTP-fed lambs were higher than that of INFGTP0 lambs, especially from days 28 to 42. The FECs of all GTP-fed lambs were higher than those of uninfected lambs but lower than that of INFGTP0 lambs. The PCVs of all infected lambs were lower than those of uninfected lambs, but PCV increased with increasing amounts of GTP supplementation. Furthermore, supplementation with different concentrations of GTP significantly reduced the numbers of adult H. contortus, including both males and females (P<0.0001), and the H. contortus burden in INFGTP6 lambs was reduced to uninfected levels. Overall, the SAA, Hp, LBP, and α1AGP concentrations of all infected lambs were higher than those of uninfected lambs from days 0 to 56. Two peaks in expression were observed from days 0 to 3 and at day 28, and APP concentrations of all GTP-fed lambs were lower than those of INFGTP0 lambs, except for SAA in INFGTP6 lambs. In conclusion, quantitative measurements of APP responses to H. contortus infection provide valuable diagnostic information for monitoring infection progression and treatment responses in lambs. An appropriate dose of dietary GTP supplementation can increase host resistance by reducing H. contortus burden and weight loss and suppressing blood APP expression.