Modulation of cell death mechanisms via α-Ag2WO4 morphology-dependent factors.

The cytotoxic of α-Ag2WO4 synthesized in different morphologies (cuboidal (AW-C), hexagonal rod-like (AW-HRL) and nanometric rod-like (AW-NRL) was analyzed to understand the impact of morphological modulation on the toxicity of 3 T3 cell lines in the dark and when photoactivated by visible light. Pathways of toxicity were examined, such as parameters and electrostatic interaction, uptake, ion release and ROS production. Cytotoxicity was observed for all samples after reaching concentrations exceeding 7.8 µg/mL. Uptake tests demonstrated that the samples were not internalized by cells, likely due to their negative surface charge. AW-NRL exhibited autophagy in the absence of light and during photoactivation, primarily attributed to its ability to generate singlet oxygen. Analyzing intercellular ROS and RNS production, AW-HRL induced an increase in NO through exposure to photo-generated hydroxyl radicals, while AW-NRL showed increases only at non-photoactivated concentrations and AW-C did not exhibit increases. Interestingly, in the dark, these cells showed a low propensity for apoptosis, with late apoptosis and necrosis being more pronounced. When photoactivated, this behavior changed, revealing predominantly apoptotic and late apoptotic cell death. There is a need for an understanding of how morphology can alter the biological properties of α-Ag2WO4 to predict and optimize its effects on cellular responses.

Red biocolorant from endophytic Talaromyces minnesotensis: production, properties, and potential applications.

Fungal colorants are gradually entering the global color market, given their advantages of being less harmful to human health, as well as having greater stability and biotechnological potential, compared to other natural sources. The present work concerns the isolation and identification of an endophytic filamentous fungus, together with the chemical characterization and assessment of the fluorescence, toxicity, stability, and application potential of its synthesized red colorant. The endophytic fungus was isolated from Hymenaea courbaril, a tree from the Brazilian savannah, and was identified as Talaromyces minnesotensis by phenotypic and genotypic characterization. Submerged cultivation of the fungus resulted in the production of approximately 12 AU500 of a red biocolorant which according to LC-DAD-MS analysis is characterized by being a complex mixture of molecules of the azaphilone class. Regarding cytotoxicity assays, activity against human hepatoblastoma (HepG2) cells was only observed at concentrations above 5.0 g L-1, while antimicrobial effects against pathogenic bacteria and yeast occurred at concentrations above 50.0 g L-1. The biocolorant showed high stability at neutral pH values and low temperatures (10 to 20 °C) and high half-life values (t1/2), which indicates potential versatility for application in different matrices, as observed in tests using detergent, gelatin, enamel, paint, and fabrics. The results demonstrated that the biocolorant synthesized by Talaromyces minnesotensis has potential for future biotechnological applications. KEY POINTS: • An endophytic fungus, which was isolated and identified, synthesize a red colorant. • The colorant showed fluorescence property, low toxicity, and application potential. • The red biocolorant was highly stable at pH 8.0 and temperatures below 20°C.

Effects of mesenchymal stromal cells on motor function and collagen in the skeletal muscles of rats with type I diabetes.

The present study aimed to evaluate the effects of mesenchymal stromal cell (MSC) transplantation on motor function and collagen organization in the muscles of rats with type 1 diabetes mellitus. Male Wistar rats were randomly assigned to three groups: control (C), diabetic (DM) and diabetic treated with MSCs (DM-MSCs). Diabetes was induced by streptozotocin (50 µg/kg). Bone marrow cells were isolated from the tibia and femur. After 10 weeks of DM induction, the DM-MSC rats received four i.p. injections of MSCs (1 × 106). Ten weeks after MSC transplantation, motor performance was evaluated by the rotarod test and the anterior tibial (TA) muscles were collected for morphometric and quantification of collagen birefringence by polarizing microscopy analysis. Motor performance of the DM group was significantly reduced when compared to the C group and increased significantly in the DM + MSC group. The TA muscle mass was significantly reduced in the DM and DM + MSC groups compared to the C group. The connective tissue increased in the DM group compared to the C group and decreased in the DM + MSC group. The percentage collagen birefringence decreased significantly in the DM group when compared to the C group and increased in the DM + MSC group. Motor performance was positively correlated with collagen birefringence and negatively correlated with percentage of connective tissue. The results indicate that MSC transplantation improves both motor function and the collagen macromolecular organization in type 1 DM.

Porous poly (D,L-lactide-co-glycolide) acid/biosilicate® composite scaffolds for bone tissue engineering.

This study evaluated the effects of the Biosilicate® and poly (D,L-lactic-co-glycolic) acid composites on bone repair in a tibial bone defect model in rats by means of using histological evaluation (histopathological and morphometric analysis) and gene expression analysis. Eighty male Wistar rats (12 weeks old, weighing ±300 g) were randomly divided into two groups: Biosilicate® group (BG) and Biosilicate® /PLGA group (BG/PLGA). Each group was euthanized at 3, 7, 14, and 21 days after surgery (n = 10 animals per time point). The main findings showed that the incorporation of PLGA into BG had a significant effect on the morphological structure of the material, accelerating mass loss, decreasing the pH and increasing the calcium release. Furthermore, histologic analysis revealed that the BG/PLGA showed increased material degradation, accompanied by higher bone formation compared to BG, after 21 days of implantation. In addition, qRT-PCR analysis showed that BG/PLGA induced an upregulation of the osteogenic genes related to BMP4, Runx2, ALP, and OC. These results show that the present BG/PLGA composite may be used as a bone graft for inducing bone repair. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 63-71, 2017.

Menthol and Menthone Associated with Acetylsalicylic Acid and Their Relation to the Hepatic Fibrosis in Schistosoma mansoni Infected Mice.

Schistosomiasis is an important parasitic disease caused by Schistosoma mansoni, an intravascular trematode. Schistosomiasis treatment is limited to just one drug, Praziquantel (PZQ). Thus, studies on new antischistosomal compounds are of fundamental importance to disease control. Here we report on the effects of Mentha piperita L. compounds - menthol and menthone - in association with acetylsalicylic acid (ASA) in the regulation of hepatic fibrosis caused by schistosomiasis granulomas. Six different groups of Swiss rats were infected with 80 cercariae. Two groups received only menthol and menthol treatment at different concentrations (30 and 50 mg/kg); two groups received treatment with the same concentration of menthol and menthol, but associated the ASA. All groups received treatment for 14 consecutive days from the 35 days after the parasitic infection. In addition, three other groups were used: uninfected and untreated group, infected and untreated group and infected group treated with the commercial drug (single dose). Parasitological, cytological and histological analyses were performed. Results showed a significant reduction on the number of eosinophils found in the peritoneal cavity lavage (LPC) in all treated groups and on the number of eosinophils found in the blood of PZQ treated group, in the blood of the group treated with 30 mg/kg of Mentaliv® and in the blood of group treated with 50 mg/kg Mentaliv® + ASA when compared to the infected group. All treated groups presented a reduction in the parasite load, represented by the number of S. mansoni eggs, in the experimental group treated with 30 mg/kg of menthol and menthone a 62.80% reduction was observed and in the experimental group treated with 50 mg/kg of menthol and menthone + ASA a reduction of 64.21% was observed. In the liver histological analysis we observed that all Mentaliv® treated groups expressed a unique cytological profile, with diffused cells through the granuloma. In the experimental group treated with 50 mg/kg of Mentaliv® + ASA it was possible to observe the formation of type III collagen fibers, a typical wound healing characteristic. Our data strongly suggest that both the hepatic fibrosis and the inflammatory process were regulated through the schistosomiasis granulomatous process after treatment with menthol and menthone associated with ASA.

Immunological and parasitological parameters in Schistosoma mansoni-infected mice treated with crude extract from the leaves of Mentha x piperita L.

Schistosomiasis is a chronic disease caused by an intravascular trematode of the genus Schistosoma. Praziquantel is the drug used for treatment of schistosomiasis; nevertheless failure of treatment has been reported. Consequently, the identification of new effective schistosomicidal compounds is essential to ensure the effective control of schistosomiasis in the future. In this work we investigated the immunomodulatory and antiparasitic effects of the crude leaves extract of Mentha x piperita L. (peppermint) on murine Schistosomiasis mansoni. Female Balb/c mice were infected each with 50 S. mansoni cercariae and divided into three experimental groups: (I) untreated; (II) treated daily with M. x piperita L. (100mg/kg) and III) treated on 1/42/43 days post-infection with Praziquantel (500mg/kg). Another group with uninfected and untreated mice was used as a control. Subsequently, seven weeks post-infection, S. mansoni eggs were counted in the feces, liver and intestine. Worms were recovered by perfusion of the hepatic portal system and counted. Sera levels of IL-10, IL-5, IL-13, IFN-γ, IgG1, IgE and IgG2a were assayed by ELISA. Animals treated with a daily dose of M. x piperita L. showed increased sera levels of IL-10, IFN-γ, IgG2a and IgE. Besides, M. x piperita L. treatment promoted reduction in parasite burden by 35.2% and significant decrease in egg counts in the feces and intestine.

Role of leukotrienes on protozoan and helminth infections.

Leukotrienes (LTs), formed by the 5-lipoxygenase-(5-LO-) catalyzed oxidation of arachidonic acid, are lipid mediators that have potent proinflammatory activities. Pharmacologic or genetic inhibition of 5-LO biosynthesis in animals is associated with increased mortality and impaired clearance of bacteria, fungi, and parasites. LTs play a role in the control of helminth and protozoan infections by modulating the immune system and/or through direct cytotoxicity to parasites; however, LTs may also be associated with pathogenesis, such as in cerebral malaria and schistosomal granuloma. Interestingly, some proteins from the saliva of insect vectors that transmit protozoans and secreted protein from helminth could bind LTs and may consequently modulate the course of infection or pathogenesis. In addition, the decreased production of LTs in immunocompromised individuals might modulate the pathophysiology of helminth and protozoan infections. Herein, in this paper, we showed the immunomodulatory and pathogenic roles of LTs during the helminth and protozoan infections.

pcDNA-IL-12 vaccination blocks eosinophilic inflammation but not airway hyperresponsiveness following murine Toxocara canis infection.

We have investigated the effect of pcDNA3-CpG and pcDNA-IL-12, delivered by intradermal gene gun administration, on the blood/lung eosinophilia, airway hyperresponsiveness as well as the immune response in a murine model of toxocariasis. Our results demonstrated that pcDNA-IL-12 but not pcDNA3-CpG vaccination led to a persistent lower blood/bronchoalveolar eosinophilia following Toxocara canis infection, as pcDNA3-CpG led only to an early transient blockage of eosinophil transmigration into bronchoalveolar fluid following T. canis infection. Prominent Type-1 immune response was pointed out as the hallmark of T. canis infection following pcDNA-IL-12 vaccination. Outstanding IFN-gamma/IL-4 ratio besides low levels of IgG1 with subsequent high IgG2a/IgG1 ratio further characterized a Type-1 polarized immunological profile in pcDNA-IL-12-vaccinated animals. Nevertheless, only pcDNA3-CpG was able to prevent airway hyperresponsiveness induced by T. canis infection. The persistent airway hyperresponsiveness observed in pcDNA-IL-12-vaccinated animals demonstrated that the airway constriction involved other immunological mediator than those blocked by pcDNA-IL-12. Together, these data indicated that pcDNA-IL-12 and pcDNA3-CpG vaccines have distinct therapeutic benefits regarding the eosinophilic inflammation/airway hyperresponsiveness triggered by T. canis infection, suggesting their possible use in further combined therapeutic interventions.

Leukotrienes play a role in the control of parasite burden in murine strongyloidiasis.

It is clear that leukotrienes mediate inflammatory response; new aspects of leukotriene function have recently been described. In this study, we demonstrate that leukotrienes are key chemical mediators in the control of parasite burdens in mice infected with Strongyloides venezuelensis. High leukotriene levels were detected in the lungs and small intestines of Swiss mice. In infected Swiss mice treated with MK886, a leukotriene synthesis inhibitor, numbers of adult worms, and eggs/g/feces were greater than in infected-only animals. The MK886 treatment inhibited leukotriene B(4) production in the lungs and small intestines, albeit on different postinfection days. Similarly, parasite burdens and eggs/g/feces were greater in 5-lipoxygenase(-/-) mice than in wild-type animals. These observation were confirmed by histopathological study of the duodena. We subsequently observed significant lower numbers of eosinophils and mononuclear cells in the blood, peritoneal cavity fluid, and bronchoalveolar lavage fluid of Swiss mice treated with MK886. In the lung parenchyma of infected animals, MK886 significantly inhibited synthesis of IL-5 at the beginning of infection, whereas levels of IL-12 increased progressively throughout the postinfection period. However, levels of leukotriene C(4), PGE(2), TNF-alpha, IL-3, IL-4, IFN-gamma, and IL-10 were comparable between the treated and untreated groups. Nevertheless, IgE and IgG1 (but not IgG2a) synthesis was also significantly inhibited by MK886 administration. Therefore, in S. venezuelensis-infected mice, adult worm and egg burdens are leukotriene dependent. These findings indicate potential immunostimulatory strategies involving leukotriene administration, and may serve as an alert to physicians treating Strongyloides stercoralis-infected patients presenting asthma-like symptoms because use of 5-lipoxygenase inhibitors may worsen the infection.