Trichinella spiralis Larval Extract as a Biological Anti-Tumor Therapy in a Murine Model of Ehrlich Solid Carcinoma.

Trichinella spiralis (T. spiralis) is an immunomodulating parasite that can adversely affect tumor growth and extend host lifespan. The aim of this study was to elucidate the mechanisms by which T. spiralis larval antigens achieve this effect using Ehrlich solid carcinoma (ESC) murine model. Assessment was done by histopathological and immunohistochemical analysis of caspase-3, TNF-α, Ki-67 and CD31. Additionally, Bcl2 and Bcl2-associated protein X (Bax) relative gene expression was assessed by molecular analysis for studying the effect of T. spiralis crude larval extract (CLE) antigen on tumor necrosis, apoptosis, cell proliferation and angiogenesis. We found that both T. spiralis infection and CLE caused a decrease in the areas of necrosis in ESC. Moreover, they led to increased apoptosis through activation of caspase-3, up-regulation of pro-apoptotic gene, Bax and down-regulation of anti-apoptotic gene, Bcl2. Also, T. spiralis infection and CLE diminished ESC proliferation, as evidenced by decreasing Ki-67. T. spiralis infection and CLE were able to suppress the development of ESC by inhibiting tumor proliferation, inducing apoptosis and decreasing tumor necrosis, with subsequent decrease in tumor metastasis. T. spiralis CLE antigen may be considered as a promising complementary immunotherapeutic agent in the treatment of cancer.

Nanocurcumin: A Promising Therapeutic Candidate for Experimental Trichinellosis.

In our pursuit of an alternative drug against Trichinella spiralis, we assessed the effectiveness of nanocurcumin in alleviating pathogenesis, parasitological factors, MMP-9 levels, and its expression in the enteral and parenteral phases of infection. The nanocurcumin particles, with a spherical shape and a size of 100 ± 20 nm, were used in the study. Eighty mice were divided into four groups: the control group, the untreated infected group, the nanocurcumin-treated group, and the albendazole-treated group. The nanocurcumin-treated group exhibited a statistically significant increase in the percentage of lymphocytes, along with a reduction in neutrophils, monocytes, and eosinophils compared to the untreated, infected group. Both the nanocurcumin (87.2 and 97.3%) and the albendazole-treated groups (99.8 and 98.2%) showed a significant reduction in the mean number of intestinal worms and encysted larvae, respectively. The treated groups exhibited normal intestinal villi, suppression of the inflammatory process, and fewer instances of degenerated larvae in the diaphragm and muscle compared to the untreated, infected group. Immunohistochemistry and ELISA analyses revealed a significant downregulation of MMP-9 levels in the intestines and muscles of the treated groups. Our data demonstrate that nanocurcumin contains highly versatile molecules capable of modulating biological activity against inflammation and its pathway markers.

Lentinula edodes extract increases goblet cell number and Muc2 expression in an intestinal inflammatory model of Trichinella spiralis infection.

AHCC® is a standardized extract of cultured mushroom (Lentinula edodes) mycelia with a wide variety of therapeutic effects including anti-inflammatory, antitumor and antiviral effects. Trichinellosis, a food-borne parasitic zoonosis is caused by the nematode Trichinella spp. Infection with Trichinella is characterized by the induction of a Th1-type response at the beginning of the intestinal phase, followed by a dominant Th2-type response which is essential for parasite expulsion. The aim of this study was to evaluate the immunomodulatory effect of AHCC® in a murine model of Trichinella spiralis infection. Swiss CD1 mice were infected with T. spiralis larvae and treated with AHCC®. Standard treatment with albendazole (ABZ) was used as control in the assessment of parasite burden. The small intestine was taken out and the proximal segment was evaluated for several parameters: gene expression of immune and stress-reticulum mediators, histological damage score, goblet cell count and Mucin 2 (Muc2) gene expression. AHCC® modulated expression levels of both Th1 and Th2 cytokines and reduced histological damage score. In addition, AHCC® diminished the number of adults of T. spiralis in treated animals. AHCC® treatment anticipates T. spiralis expulsion and increases goblet cell number and Muc2 gene expression.

ß-Glucan-triggered Akkermansia muciniphila expansion facilitates the expulsion of intestinal helminth via TLR2 in mice.

Trichinellosis caused by Trichinella spiralis is a serious zoonosis with a worldwide. ß-Glucans (BG) are readily used across the world with noted health benefits, yet the effect and mechanism of BG on host defense against helminth infection remain poorly understood. We observed that BG could trigger worm expulsion via mucus layer independently of type 2 immunity, but was dependent on the gut microbiota in mice. BG restored the abundance of Bacteroidetes and Proteobacteria changed by T. spiralis infection to the control group level and markedly increased the relative abundance of Verrucomicrobia. Akkermansia (belonging to Verrucomicrobia) were significantly expanded in the BG + T. spiralis group. Notably, daily oral supplementation of pasteurized A. muciniphila has a stronger deworming effect than live bacteria and interacted with TLR2. These findings of this study is an easily implementable strategy to facilitate expulsion of gastrointestinal helminth.

Effect of mast cell stabilization on angiogenesis in primary and secondary experimental Trichinella spiralis infection.

BACKGROUND: Mast cells are known to affect the primary and secondary immune responses against parasites, and this effect is partially mediated through the release of pro-angiogenic mediators. The aim of this study was to explore the effect of the mast cell stabilizer (MCS), ketotifen, with and without albendazole, an anti-parasitic prescription medicine, on the inflammatory response against Trichinella spiralis, with the overall aim to investigate its effect on angiogenesis accompanying nurse cell formation. METHODS: The effect of ketotifen and albendazole was explored in eight groups of female BALB/c mice. Four groups were sensitized with a small dose of T. spiralis larvae. The drug regimen was then applied to both sensitized (challenged) and non-sensitized mice. The parasite load was assessed by histopathological examination of the small intestine and muscle tissue, and angiogenesis was assessed by immunohistochemistry to determine the expression of vascular endothelial growth factor (VEGF). RESULTS: Sensitized mice showed a significantly lower parasite load and a more pronounced inflammatory response than mice receiving a single infective dose of T. spiralis larvae. All treated groups showed a significant reduction in parasite count compared to the control groups (groups IAa and IBa), reaching approximately an 98.8% reduction in adult parasite count in the sensitized group treated with albendazole (groups IIAb and IIBb). MCS significantly decreased the parasite count during both the intestinal or muscular phases, reduced tissue inflammation, and decreased local VEGF expression, both in the non-sensitized and sensitized groups. CONCLUSION: Sensitization with a low dose of T. spiralis larvae was found to confer a partial protective immunity against re-infection and to positively affect the study outcomes, thus underlining the importance of vaccination, but after extensive studies. The anti-angiogenic effect of MCS protects against larval encystation during the muscle phase. The anti-angiogenic potential of albendazole suggests that the action of this anti-helminthic during trichinellosis is not confined to structural damage to the parasite cuticle but includes an effect on host immunopathological response.

Niosomal versus nano-crystalline ivermectin against different stages of Trichinella spiralis infection in mice.

Ivermectin (IVM) is one of the competitive treatments used for trichinellosis. However, several studies linked its efficacy with early diagnosis and administration to tackle the intestinal phase with limited activity being recorded against encysted larvae. The aim of this study was to employ niosomes for enhancing effectiveness of oral IVM against different stages of Trichinella spiralis (T. spiralis) infection with reference to nano-crystalline IVM. Mice were randomized into four groups: group Ι, 15 uninfected controls; group ΙΙ, 30 infected untreated controls; group ΙΙΙ, 30 infected nano-crystalline IVM treated, and group ΙV, 30 infected niosomal IVM treated. All groups were equally subdivided into 3 subgroups; (a) treated on the 1st day post infection (dpi), (b) treated on the 10th dpi, and (c) treated on the 30th dpi. Assessment was done by counting adult worms and larvae plus histopathological examination of jejunum and diaphragm. Biochemical assessment of oxidant/antioxidant status, angiogenic, and inflammatory biomarkers in intestinal and muscle tissues was also performed. Both niosomes and nano-crystals resulted in significant reduction in adult and larval counts compared to the infected untreated control with superior activity of niosomal IVM. The superiority of niosomes was expressed further by reduction of inflammation in both jejunal and muscle homogenates. Biochemical parameters showed highly significant differences in all treated mice compared to infected untreated control at different stages with highly significant effect of niosomal IVM. In conclusion, niosomal IVM efficacy exceeded the nano-crystalline IVM in treatment of different phases of trichinellosis.

Therapeutic efficacy of mebendazole and artemisinin in different phases of trichinellosis: a comparative experimental study.

The present work aimed at studying the efficacy of mebendazole (MBZ) compared to artemisinin (ART) for the treatment of trichinellosis at various phases of infection. Seventy Swiss albino mice were orally infected by 300 Trichinella spiralis (T. spiralis) larvae. Mice were divided into infected untreated control group and infected groups treated with 50 mg kg-1 MBZ and 300 mg kg-1 ART for three and five consecutive days, respectively, at the enteral phase [2-4 days post infection (PI)], invasive phase (10-12 days PI) and encapsulated phase (28-30 days PI). All mice were sacrificed 35-42 days PI. MBZ and ART revealed a significant decrease in mean larval counts and increase of larval per cent reduction (LR %) when treatment was initiated during the enteral phase compared to the other phases. MBZ showed significantly higher LR % (99.7, 83.95 and 89.65%) than ART (80.58, 67.0 and 79.2%) when administered at the three infection phases. Histopathological study showed a decrease in the number of encysted larvae, their surrounding cellular infiltrates and increased regenerative muscles in all treated mice. In conclusion, ART possesses a substantial anthelmintic activity against T. spiralis infection in mice both at the enteral and encapsulated phases, yet, significantly lower than MBZ.

Oxidative stress mediated apoptotic potential of mefloquine on experimental trichinellosis.

Conventional anthelmintics such as albendazole could not achieve complete cure of trichinellosis till now. The antimalarial mefloquine mediates oxidative stress and disrupts lysosomal functions leading to cell death. Therefore, the aim of this work was to investigate the effect of mefloquine on experimental acute and chronic trichinellosis and to clarify the possible mechanisms of such effects. Mice were divided into four groups; Group I: Uninfected untreated control (20 mice); Group II: Infected untreated control (40 mice); Group III: infected and treated with albendazole (400 mg/kg) (40 mice); Group IV: infected and treated with mefloquine (300 mg/kg) (40 mice). All infected treated groups were equally subdivided into 2 subgroups; (a) treated on the 2nd day post infection (dpi) for 3 days, (b) treated on the 35th dpi for 5 days. Parasitological adults and larvae counting besides immunohistopathological examination of intestines and muscles were done. Biochemical assay of oxidant/antioxidant status, apoptotic, cytoprotective and inflammatory biomarkers in intestinal and muscle homogenates were achieved. Results showed that both albendazole and mefloquine significantly reduced adults and larvae counts with higher efficacy of albendazole in the intestinal phase and superiority of mefloquine in the muscle phase. The superiority of mefloquine was indicated by increased inflammatory immune infiltration and decreased anti-apoptotic immunohistochemical markers expression in both jejunal and muscle tissues. Biochemically, mefloquine treatment showed highly significant oxidative, apoptotic and inflammatory effects. So, our results suggest that mefloquine might be a superior treatment for chronic trichinellosis.

Lentinan improved the efficacy of vaccine against Trichinella spiralis in an NLRP3 dependent manner.

There is an urgent need for the development of new, improved vaccine adjuvants against T. spiralis infection. Polysaccharides are effective, safe, and biodegradable as adjuvant. In our study, we first observed the protective efficacy of lentinan as adjuvant against helminth T. spiralis infection. Recombinant T. spiralis Serpin (rTs-Serpin) immunoscreened from a cDNA library of T. spiralis, as a vaccine, protect host against Trichinella infection. The reduction rate of helminth burden of rTs-Serpin+lentinan-immunized mice was significantly increased compared with rTs-Serpin+FCA -immunized mice. rTs-Serpin+lentinan induced IgG1-dominant immune response and higher levels of IFN-γ and IL-4. rTs-Serpin+lentinan displayed a lower reduction rate of parasite burden in NLRP3-/- mice than that in WT mice and lower level of IgG1 than that in WT mice. The level of IL-4, but not IFN-γ, from NLRP3-/- mice immunized by rTs-Serpin+lentinan was significantly lower than that from WT mice, suggesting that NLRP3 is associated with rTs-Serpin+lentinan -triggering Th2 protective immunity against T. spiralis infection. In summary, we revealed that lentinan was a novel adjuvant against T. spiralis infection via NLRP3. NLRP3 therefore represents an important target for adjuvant discovery and the control of T. spiralis infection.

Protection against Trichinella spiralis in BALB/c mice via oral administration of recombinant Lactobacillus plantarum expressing murine interleukin-4.

Interleukin-4 (IL-4), an immunomodulatory cytokine derived from activated T lymphocytes were shown to regulate Th2-type immune responses. It plays an important role in anti-parasitic infections. In this study, a recombinant plasmid was designed using murine IL-4 co-expressed with pgsA anchor system of Lactobacillus plantarum NC8 and was delivered by live Lactobacillus plantarum NC8, which exhibited an enhanced immunogenicity in protection of BALB/c mice from infection with Trichinella spiralis. The results showed that the levels of serum IgG1 and mucosal secretory IgA (sIgA) were both increased significantly in mice orally inoculated with NC8-pSIP409-pgsA-mIL-4, and the Th2 phenotype immune response was up-regulated. A 29.9 % reduction in adult worm burden at 7 days post-infection (dpi) and 83.3 % reduction in muscle larvae burden at 28 dpi were observed in immune-stimulated mice with NC8-pSIP409-pgsA-mIL-4. Moreover, weight loss and pathological changes were also improved in mice of NC8-pSIP409-pgsA-mIL-4 group. Taken together, it suggests that NC8-pSIP409-pgsA-mIL-4 could improve the intestinal mucosal immunity and promoted the elimination of the adult worm in Trichinella-infected mice. This study laid the foundation for the development of a novel vaccines against Trichinellosis.

Resveratrol reduces oxidative damage and inflammation in mice infected with Trichinella spiralis.

Trichinellosis is a serious food-borne zoonotic infection of cosmopolitan distribution. Currently, treatment for trichinellosis is far from ideal. Given the important role of oxidative stress and immune-mediated inflammation in the pathogenesis of trichinellosis, this study was designed to evaluate the possible protective effects of resveratrol (RSV) during the intestinal and muscular phases of Trichinella spiralis infection in mice. The oral administration of RSV at a dose of 20 mg/kg once daily for two weeks resulted in significant reductions in both adult and larval counts; significant improvements in the redox status of the small intestine and muscles; a significant reduction in interleukin 4, pentraxin 3 and vascular endothelial growth factor expression; and the mitigation of intestinal and muscular inflammation. In conclusion, this study identifies RSV as a promising agent for the treatment of experimental trichinellosis, and more studies in experimental animals and humans are worth consideration.

Protective immunity in mice vaccinated with a novel elastase-1 significantly decreases Trichinella spiralis fecundity and infection.

Trichinella spiralis is an important foodborne parasitic nematode that represents an enormous threat to the food safety of pork meat. The development of a preventive vaccine is valuable for the prevention and control of Trichinella infection in domestic pigs to ensure pork safety. Elastase is a trypsin-like serine protease that hydrolyzes the host's diverse tissue components and participates in parasite penetration, and it might be a novel vaccine target molecule. The aim of this study was to assess the protective immunity produced by vaccination with a novel Trichinella spiralis elastase-1 (TsE) in a mouse model. The results demonstrate that subcutaneous vaccination of mice with rTsE elicited a systemic humoral response (high levels of serum IgG and subclass IgG1/IgG2a and IgA) and significant local enteral mucosal sIgA responses. Anti-rTsE IgG recognized the native TsE at the cuticle, stichosome of intestinal infective larvae and adult worm (AW), and intrauterine embryos of female AW. The rTsE vaccination also produced a systemic and local mixed Th1/Th2 response, as demonstrated by clear elevation levels of Th1 cytokines (IFN-γ, IL-2) and Th2 cytokines (IL-4, IL-10) after spleen, mesenteric lymph node and Peyer's patch cells from immunized mice were stimulated with rTsE. The immunized mice exhibited a 52.19% reduction in enteral AW and a 64.06% reduction in muscle larvae after challenge infection. The immune response triggered by rTsE vaccination protected enteral mucosa from larval intrusion, suppressed larval development and reduced female fecundity. The results indicate that TsE may represent a novel target molecule for anti-T. spiralis vaccines.

Chitosan coated nanostructured lipid carriers for enhanced in vivo efficacy of albendazole against Trichinella spiralis.

The study investigated chitosan coated nanostructured lipid carriers (NLCs) for oral delivery of albendazole in treatment of trichinellosis. NLCs comprised precirol and oleic acid with Tween and Span 80. Dicetylphosphate was used as charging agent to allow chitosan coating. Trichinella spiralis infected mice were used and albendazole suspension, coated or uncoated NLCs were orally administered at different stages of infection. NLCs were spherical with size of 188 and 200 nm for coated and uncoated NLC, respectively. Treatment during intestinal phase reduced worm count with NLCs showing better rank. This was reflected further by reduced larvae count and improved histopathological features. Starting treatment in the migrating phase reduced larval count by 62.9, 99.6 and 89.5 % after administration of suspension, coated and uncoated NLCs, respectively. The same rank was recorded for the encysted phase. NLCs enhanced the efficacy of albendazole against Trichinella spiralis compared with suspension with chitosan coated NLCs being superior.

Sanguinarine has anthelmintic activity against the enteral and parenteral phases of trichinella infection in experimentally infected mice.

Trichinellosis is a zoonotic parasitic disease caused by Trichinella spiralis, and it is also a widely prevalent foodborne parasitic disease. At present, albendazole and benzimidazole are the most commonly used therapeutic drugs for the clinical treatment of trichinellosis, but they have many side effects. Sanguinarine is a benzophenanthridine alkaloid that has biological activity, such as antibacterial, antitumour and antiparasitic activities. Therefore, the present study aimed to evaluate the anti-Trichinella effect of sanguinarine in vivo and in vitro. The results showed that sanguinarine had a lethal effect on muscle larvae, adults and new-borne larvae in vitro. The damage to adults treated with sanguinarine was observed by scanning electron microscopy. Sanguinarine could significantly reduce the burden of worms in mice during the pre-adult, migrating larva and encysted larva stages. The ratio of intestinal villus to crypt (V/C) in mice treated with sanguinarine was significantly higher than that in non-treated control mice. Compared with the non-treated control group, the sanguinarine-treated group exhibited a significantly increased number of small intestine goblet cells. The level of reactive oxygen species (ROS) in the serum of mice treated with sanguinarine was significantly higher than that of the control group mice in the pre-adult and encysted larva stages. This study suggests that sanguinarine is a potential drug against trichinellosis.

Effect of Wortmannilactone F on Trichinella spiralis Enteral in Mice.

Trichinosis is a worldwide zoonotic disease closely related to cultural and dietary habits caused by a nematode Trichinella spp. The drugs for its prevention and treatment are still not thoroughly defined. Wortmannilactone F was used to value the therapeutic effects on the worm reduction rates, change of the intestinal mucosa, and the host's body's immune activity in this experiment. BALB/c mice were orally fed with 200 infective Trichinella spiralis larvae. Then, T. spiralis-infected mice were treated with wortmannilactone F (50, 100, and 200 mg/kg). The number and morphological analysis of adult worm, the expression of Factor associated suicide (Fas), and the level of SIgA in the mice were investigated. Wortmannilactone F showed dose-dependent anthelmintic effects by causing mortality of worms, obvious damaging effects on mature T. spiralis' surface and their digestive systems, decreasing the expression of mice's intestinal mucosa's Fas protein, and reducing intestinal mucosa's level of SIgA secretions. Wortmannilactone F is expected to be a potential therapeutic drug for trichinellosis treatment.

Isolation of a Novel Flavanonol and an Alkylresorcinol with Highly Potent Anti-Trypanosomal Activity from Libyan propolis.

Twelve propolis samples from different parts of Libya were investigated for their phytochemical constituents. Ethanol extracts of the samples and some purified compounds were tested against Trypanosoma brucei, Plasmodium falciparum and against two helminth species, Trichinella spiralis and Caenorhabditis elegans, showing various degrees of activity. Fourteen compounds were isolated from the propolis samples, including a novel compound Taxifolin-3-acetyl-4'-methyl ether (4), a flavanonol derivative. The crude extracts showed moderate activity against T. spiralis and C. elegans, while the purified compounds had low activity against P. falciparum. Anti-trypanosomal activity (EC50 = 0.7 µg/mL) was exhibited by a fraction containing a cardol identified as bilobol (10) and this fraction had no effect on Human Foreskin Fibroblasts (HFF), even at 2.0 mg/mL, thus demonstrating excellent selectivity. A metabolomics study was used to explore the mechanism of action of the fraction and it revealed significant disturbances in trypanosomal phospholipid metabolism, especially the formation of choline phospholipids. We conclude that a potent and highly selective new trypanocide may be present in the fraction.

Synthesis and characterization of a new cyclodextrin derivative with improved properties to design oral dosage forms.

This work aimed to synthesize a novel ß-cyclodextrin derivative, itaconyl-ß-cyclodextrin to evaluate whether albendazole inclusion complexes with the new ß-cyclodextrin derivative-improved albendazole dissolution efficiency and its anthelminthic activity. The new derivative was thoroughly evaluated and characterized, and an average degree of substitution of 1.4 per cyclodextrin molecule was observed. Albendazole:itaconyl-ß-cyclodextrin complexes were prepared by spray drying procedures and investigated using phase solubility diagrams, dissolution efficiency, X-ray diffraction, differential scanning calorimetry, Fourier transform infrared, scanning electronic microscopy, mass spectrometry, and nuclear magnetic resonance spectroscopy. Phase solubility diagrams and mass spectrometry studies showed that the inclusion complex was formed in an equimolar ratio. Stability constant values were 602 M-1 in water, and 149 M-1 in HCl 0.1 N. Nuclear magnetic resonance experiments of the inclusion complex showed correlation signals between the aromatic and propyl protons of albendazole and the itaconyl-ß-cyclodextrin inner protons. The studies indicated solid structure changes of albendazole included in itaconyl-ß-cyclodextrin. The maximum drug release was reached at 15 min, and the inclusion complex solubility was 88-fold higher than that of the pure drug. The in vitro anthelmintic activity assay showed that the complex was significantly more effective than pure albendazole.

Killing the muscular larvae of Trichinella spiralis and the anti-fibrotic effect of the combination of Wortmannilatone F and recombinant G31P in a murine model of trichinellosis.

Although trichinosis is one of the global food-borne parasitic diseases and is considered an emerging/re-emerging disease that has been reported in 66 countries, the drugs for its prevention and treatment have not been thoroughly investigated. Wortmannilactone F (WF) has been reported as a blocker of the helminth mitochondria respiratory chain by inhibiting NADH-fumarate reductase in the mitochondrial inner membrane. CXCL8 (3-73) K11R/G31 P(G31 P) has been reported as a CXCL8 analogue that has the affinity to CXCR1 and CXCR2. Male BALB/c mice were orally fed with 150 infective Trichinella spiralis (T. spiralis) larvae. Then, T. spiralis-infected mice were treated with WF and G31 P. The number and morphological analysis of encapsulated T. spiralis, collagen fiber accumulation, and the expression of angiogenic factors were investigated. WF and G31 P dramatically decreased the numbers of encapsulation, decreased collagen fibers, and suppressed angiogenesis. These findings indicate that the combination of WF and G31 P is a potential therapeutic strategy of Trichinellosis.

Effect of two recombinant Trichinella spiralis serine protease inhibitors on TNBS-induced experimental colitis of mice.

Inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn's disease (CD), is a chronic autoimmune disease. Parasitic infections and their products have been shown to have protective effects on autoimmune diseases, including IBD. In this experiment, 96 male BALB/c mice aged 6-8 weeks were divided randomly into two large groups: prevention and therapy. The changes in the various indicators of colitis were detected to demonstrate that Trichinella spiralis serine protease inhibitors can relieve the inflammatory severity of 2,4,6-trinitrobenzenesulphonic acid solution (TNBS)-induced colitis and to explore possible immunological mechanisms. Results showed that the disease activity index (DAI) score, myeloperoxidase (MPO) activity, macroscopic and microscopic damage degrees of colon all decreased significantly, interferon (IFN)-γ expression decreased, interleukin (IL)-4 expression increased, nuclear factor kappa B (NF)-κB expression decreased and the percentage of CD4+ CD25+ forkhead box protein 3 (FoxP3+ ) regulatory T cells (Treg ) cells in the spleen. MLN increased significantly compared to the phosphate-buffered saline (PBS)/2,4,6-trinitrobenzenesulphonic acid solution (TNB) group. We found the same results with the T. spiralis Kazal-type serine protease inhibitors (TsKaSPI)+TNBS and TsAdSPI+TNBS groups in the large prevention group and the large therapy group, compared to the TNBS+PBS group with the TNBS+TsKaSPI and TNBS+TsAdSPI groups. Immunization with TsKaSPI and TsAdSPI on the CD models showed an intervention effect, possibly because TsKaSPI and TsAdSPI induced a T helper type 2 (Th2)-type immune response and balanced the TNBS-induced Th1-type immune response.

The activities of wortmannilactones against helminth electron transport chain enzymes, structure-activity relationships, and the effect on Trichinella spiralis infected mice.

Biotransformation of wortmannilactone F (3) using the marine-derived fungus DL1103 generated wortmannilactone M (1), a novel analog of wortmannilactone, which was a reduction product of 3 at the C-3 carbonyl group. The in vitro inhibitory activities of 10 wortmannilactones, including 1, against electron transport enzymes indicated that all the wortmannilactones were selective inhibitors of NADH-fumarate reductase and NADH-rhodoquinone reductase. The structure-activity relationship analysis showed that the relative configuration of C1" and C5", the positions of double bonds, the oxygen atoms in the dihydropyran moiety, and the keto-carbonyl group in the oxabicyclo-[2.2.1]-heptane moiety were important to the inhibitory activity of wortmannilactones. In vivo studies indicated that 3 significantly decreased the number and size of adult worms in Trichinella spiralis-infected mice in a dose-dependent manner. Notable changes in the cuticle and microvilli of T. spiralis were also observed. Our data provided useful information in the research and development of polyketides with dihydropyran and oxabicyclo [2.2.1] heptane moieties as antihelminthics.