Central Carbon Metabolism in Candida albicans Biofilms Is Altered by Dimethyl Sulfoxide.

The effect of dimethyl sulfoxide (DMSO) on fungal metabolism has not been well studied. This study aimed to evaluate, by metabolomics, the impact of DMSO on the central carbon metabolism of Candida albicans. Biofilms of C. albicans SC5314 were grown on paper discs, using minimum mineral (MM) medium, in a dynamic continuous flow system. The two experimental conditions were control and 0.03% DMSO (v/v). After 72 h of incubation (37 °C), the biofilms were collected and the metabolites were extracted. The extracted metabolites were subjected to gas chromatography-mass spectrometry (GC/MS). The experiment was conducted using five replicates on three independent occasions. The GC/MS analysis identified 88 compounds. Among the 88 compounds, the levels of 27 compounds were markedly different between the two groups. The DMSO group exhibited enhanced levels of putrescine and glutathione and decreased levels of methionine and lysine. Additionally, the DMSO group exhibited alterations in 13 metabolic pathways involved in primary and secondary cellular metabolism. Among the 13 altered pathways, seven were downregulated and six were upregulated in the DMSO group. These results indicated a differential intracellular metabolic profile between the untreated and DMSO-treated biofilms. Hence, DMSO was demonstrated to affect the metabolic pathways of C. albicans. These results suggest that DMSO may influence the results of laboratory tests when it is used as a solvent. Hence, the use of DMSO as a solvent must be carefully considered in drug research, as the effect of the researched drugs may not be reliably translated into clinical practice.

Synthesis of gem-Difluorinated Keto-Sulfoxides from Sulfoxonium Ylides.

Organic molecules containing fluorine and sulfur atoms represent a large percentage of approved pharmaceuticals. Those with combination of both S and F atoms in their structure such as Xtandi, approved in 2012 for prostate cancer, indicates the importance of synthetic methods that accommodates both atoms in an organic moiety. In this study, a novel aspect of sulfoxonium ylide reactivity was explored, unveiling a streamlined and mild synthesis method for gem-difluorinated keto-sulfoxides. Our protocol offers a direct and practical approach to prepare these compounds in 14-80 % chemical yields, that were represented by 21 examples. NMR studies and Hammett correlations gave strong evidence about the mechanism of this transformation.

Protective effect of nitroglycerin ointment and dimethyl sulfoxide on necrosis of skin flaps in rats.

OBJECTIVE: To compare the protective effect of nitroglycerin ointment 2% and Dimethylsulfoxide (DMSO) in dorsal flaps of the rat. METHODS: A blind, experimental study was conducted in 24 male Wistar rats, with a mean weight of 320 (286-376) grams. Group 1: Control. Petrolatum jelly (Vaseline), n = 8, Group 2: Nitroglycerin (NTG) ointment 2% (Nitro-Bid, Altana Co.) n = 8, and Group 3: DMSO gel 90% (Neogen corp. Lexington KY, 40611), n = 8. RESULTS: A total of 24 rats were operated on in the 6-month period of this study. Using a non-parametric Mann-Whitney U-test analysis, a statistically significant p was obtained between the control group and 2% NTG ointment, both in the area of necrosis and in the healthy area (p = 0.026). In contrast, the comparison between DMSO [CH3) 2SO] and the control group (p = 0.180) and between both study groups, with a p = 0.18, was not significant. CONCLUSIONS: Our study concluded that there is a protective effect of 2% NTG ointment for flap survival in relation to the control group (petrolatum). DMSO administered topically did not show a protective effect, compared to the control group.

OBJETIVO: Comparar el efecto protector del ungüento de nitroglicerina 2% y el dimetilsulfoxido 90% en colgajos dorsales en ratas. MÉTODOS: Se realizó un estudio experimental ciego en 24 ratas Wistar macho, con un peso medio de 320 gramos. Grupo 1: Control. Petrolato n = 8, Grupo 2: Nitroglicerina unguento al 2 % (Nitro-Bid, Altana Co.), n = 8, Grupo 3. Dimetilsulfóxido al 90% (Neogen corp. Lexington KY.), n = 8. RESULTADOS: Un total de 24 ratas fueron operadas en el período de 6 meses de este estudio. Mediante un análisis no paramétrico de la prueba U de Mann Whitney, se obtuvo una p estadísticamente significativa entre el grupo control y la pomada de nitroglicerina al 2%, tanto en el área de necrosis como en el área sana (p = 0.026). Por el contrario, la comparación entre DMSO y el grupo control (p = 0.180) y entre ambos grupos de estudio, con una p = 0.18, no fue significativa. CONCLUSIONES: Nuestro estudio concluyó que existe un efecto protector de la pomada de nitroglicerina al 2% para la supervivencia del colgajo en relación al grupo control (vaselina). El DMSO administrado por vía tópica no mostró un efecto protector, en comparación con el grupo de control.

Does the application of dimethyl sulfoxide improve resin bonding to eroded dentine? Four-year in vitro evaluation.

OBJECTIVE: To evaluate the effect of dimethyl sulfoxide (DMSO) on the microtensile bond strength (µTBS) and nanoleakage (NL) of universal adhesives on eroded dentine, immediately and after four years of water storage. METHODS: Sixty-four sound human molars were distributed into 16 groups according to (1) Dentine surface (sound and eroded dentine); (2) dimethyl sulfoxide application (with or without); (3) Application mode (etch-and-rinse or self-etch) and (4) Storage time (immediate and four years). One mild universal adhesive was used (Scotchbond Universal). The restoration was then performed with a composite resin and the specimens were sectioned into resin-dentine bonded sticks. Resin-dentine bonded sticks were tested (immediately and after four years of water storage) for µTBS (0.5 mm/min) or used to assess NL. Data on µTBS and NL were analyzed using four-way ANOVA and Tukey's test (α = 0.05). RESULTS: Only the 3-way cross-product interaction 'substrate vs DMSO vs time' was statistically significant (p = 0.007). Eroded dentine showed a lower mean of µTBS and a higher mean of NL values than sound dentine. However, when DMSO was applied, no significant decrease of µTBS or NL values was observed after four years of water storage, regardless of adhesive strategies, or dentine evaluated, when compared to immediate results. SIGNIFICANCE: Water-based DMSO pre-treatments not only prevent degradation of MDP-containing simplified adhesives but also serve as a potential alternative to improve long-term bonding properties to eroded dentine. The versatility of using a single pre-treatment for both self-etch or etch-and-rinse bonding to eroded dentin may facilitate future clinical applications.

Biochemical characterization of GAF domain of free-R-methionine sulfoxide reductase from Trypanosoma cruzi.

Trypanosoma cruzi is the causal agent of Chagas Disease and is a unicellular parasite that infects a wide variety of mammalian hosts. The parasite exhibits auxotrophy by L-Met; consequently, it must be acquired from the extracellular environment of the host, either mammalian or invertebrate. Methionine (Met) oxidation produces a racemic mixture (R and S forms) of methionine sulfoxide (MetSO). Reduction of L-MetSO (free or protein-bound) to L-Met is catalyzed by methionine sulfoxide reductases (MSRs). Bioinformatics analyses identified the coding sequence for a free-R-MSR (fRMSR) enzyme in the genome of T. cruzi Dm28c. Structurally, this enzyme is a modular protein with a putative N-terminal GAF domain linked to a C-terminal TIP41 motif. We performed detailed biochemical and kinetic characterization of the GAF domain of fRMSR in combination with mutant versions of specific cysteine residues, namely, Cys12, Cys98, Cys108, and Cys132. The isolated recombinant GAF domain and full-length fRMSR exhibited specific catalytic activity for the reduction of free L-Met(R)SO (non-protein bound), using tryparedoxins as reducing partners. We demonstrated that this process involves two Cys residues, Cys98 and Cys132. Cys132 is the essential catalytic residue on which a sulfenic acid intermediate is formed. Cys98 is the resolutive Cys, which forms a disulfide bond with Cys132 as a catalytic step. Overall, our results provide new insights into redox metabolism in T. cruzi, contributing to previous knowledge of L-Met metabolism in this parasite.

Melatonin in Combination with Albendazole or Albendazole Sulfoxide Produces a Synergistic Cytotoxicity against Malignant Glioma Cells through Autophagy and Apoptosis.

Glioblastoma is the most aggressive and lethal brain tumor in adults, presenting diffuse brain infiltration, necrosis, and drug resistance. Although new drugs have been approved for recurrent patients, the median survival rate is two years; therefore, new alternatives to treat these patients are required. Previous studies have reported the anticancer activity of albendazole, its active metabolite albendazole sulfoxide, and melatonin; therefore, the present study was performed to evaluate if the combination of melatonin with albendazole or with albendazole sulfoxide induces an additive or synergistic cytotoxic effect on C6 and RG2 rat glioma cells, as well as on U87 human glioblastoma cells. Drug interaction was determined by the Chou-Talalay method. We evaluated the mechanism of cell death by flow cytometry, immunofluorescence, and crystal violet staining. The cytotoxicity of the combinations was mainly synergistic. The combined treatments induced significantly more apoptotic and autophagic cell death on the glioma cell lines. Additionally, albendazole and albendazole sulfoxide inhibited proliferation independently of melatonin. Our data justify continuing with the evaluation of this proposal since the combinations could be a potential strategy to aid in the treatment of glioblastoma.

Acute and chronic changes in porcine rete mirabile after embolization with the Menox system: angiographic and histopathological analyses.

Objective: To evaluate acute and chronic changes seen on angiographic and histopathological studies of porcine rete mirabile, comparing those treated with the Menox liquid embolic system (LES) and those treated with the Onyx LES. Materials and Methods: Five pigs, each weighing approximately 35 kg, were submitted to rete mirabile embolization under general anesthesia and fluoroscopic guidance, with the Menox LES or Onyx LES. Four animals were treated with the Menox LES and underwent cerebral angiography, followed by euthanasia, at 1, 30, 60, and 90 days after embolization. One animal was treated with the Onyx LES underwent the same procedures at 30 days after embolization. In a subsequent histopathological analysis, we compared the Menox LES and Onyx LES in terms of the acute and chronic changes observed. Results: We observed no significant changes in blood pressure, heart rate, or electrocardiographic parameters that could be attributed to the super-selective infusion of dimethyl sulfoxide or the Menox embolic agent. Fluoroscopy showed adequate material opacity, appropriate progression to the center of the rete mirabile and complete unilateral embolization. Microcatheters were uneventfully detached from the embolized nidus. We observed mild to moderate intravascular and extravascular inflammatory responses, without histological evidence of necrotizing arteritis. There were no adverse neurovascular events. Conclusion: The Menox LES appears to be safe and effective, as well as being apparently equivalent to the Onyx LES in terms of the postprocedure angiographic and histopathological findings.

Objetivo: Avaliar as alterações angiográficas e histopatológicas agudas e crônicas em rete mirabile suína tratadas com o Menox liquid embolic system (LES) e comparar essas alterações com a embolização com Onyx LES. Materiais e Métodos: A embolização da rete mirabile com Menox LES e Onyx LES foi realizada em cinco suínos pesando cerca de 35 kg sob anestesia geral e orientação fluoroscópica. Quatro animais tratados com Menox LES foram submetidos a angiografia cerebral seguida de eutanásia após 1, 30, 60 e 90 dias e um animal tratado com Onix LES foi submetido ao mesmo procedimento após 30 dias. A análise histopatológica subsequente para alterações agudas e crônicas avaliou o desempenho do Menox LES comparado ao Onyx LES. Resultados: Não foram observadas alterações significativas atribuíveis à infusão superseletiva de dimetilsulfóxido ou Menox nos parâmetros de pressão arterial, frequência cardíaca ou eletrocardiograma. A fluoroscopia mostrou opacidade adequada do material, progressão adequada para o centro da rete mirabile e embolização unilateral completa. Os microcateteres foram retirados do nidus embolizado sem complicações. Observou-se resposta inflamatória intravascular e extravascular leve a moderada, sem indício histológico de arterite necrosante. Nenhum dos casos apresentou eventos neurovasculares adversos. Conclusão: A injeção de Menox LES mostrou-se segura e eficaz, além de ser equivalente ao Onyx LES em relação aos achados angiográficos e histopatológicos pós-procedimento.

Acute and chronic changes in porcine rete mirabile after embolization with the Menox system: angiographic and histopathological analyses / Alterações angiográficas e histopatológicas agudas e crônicas da rete mirabile no modelo suíno com sistema embólico líquido Menox

Abstract Objective: To evaluate acute and chronic changes seen on angiographic and histopathological studies of porcine rete mirabile, comparing those treated with the Menox liquid embolic system (LES) and those treated with the Onyx LES. Materials and Methods: Five pigs, each weighing approximately 35 kg, were submitted to rete mirabile embolization under general anesthesia and fluoroscopic guidance, with the Menox LES or Onyx LES. Four animals were treated with the Menox LES and underwent cerebral angiography, followed by euthanasia, at 1, 30, 60, and 90 days after embolization. One animal was treated with the Onyx LES underwent the same procedures at 30 days after embolization. In a subsequent histopathological analysis, we compared the Menox LES and Onyx LES in terms of the acute and chronic changes observed. Results: We observed no significant changes in blood pressure, heart rate, or electrocardiographic parameters that could be attributed to the super-selective infusion of dimethyl sulfoxide or the Menox embolic agent. Fluoroscopy showed adequate material opacity, appropriate progression to the center of the rete mirabile and complete unilateral embolization. Microcatheters were uneventfully detached from the embolized nidus. We observed mild to moderate intravascular and extravascular inflammatory responses, without histological evidence of necrotizing arteritis. There were no adverse neurovascular events. Conclusion: The Menox LES appears to be safe and effective, as well as being apparently equivalent to the Onyx LES in terms of the postprocedure angiographic and histopathological findings.

Resumo Objetivo: Avaliar as alterações angiográficas e histopatológicas agudas e crônicas em rete mirabile suína tratadas com o Menox liquid embolic system (LES) e comparar essas alterações com a embolização com Onyx LES. Materiais e Métodos: A embolização da rete mirabile com Menox LES e Onyx LES foi realizada em cinco suínos pesando cerca de 35 kg sob anestesia geral e orientação fluoroscópica. Quatro animais tratados com Menox LES foram submetidos a angiografia cerebral seguida de eutanásia após 1, 30, 60 e 90 dias e um animal tratado com Onix LES foi submetido ao mesmo procedimento após 30 dias. A análise histopatológica subsequente para alterações agudas e crônicas avaliou o desempenho do Menox LES comparado ao Onyx LES. Resultados: Não foram observadas alterações significativas atribuíveis à infusão superseletiva de dimetilsulfóxido ou Menox nos parâmetros de pressão arterial, frequência cardíaca ou eletrocardiograma. A fluoroscopia mostrou opacidade adequada do material, progressão adequada para o centro da rete mirabile e embolização unilateral completa. Os microcateteres foram retirados do nidus embolizado sem complicações. Observou-se resposta inflamatória intravascular e extravascular leve a moderada, sem indício histológico de arterite necrosante. Nenhum dos casos apresentou eventos neurovasculares adversos. Conclusão: A injeção de Menox LES mostrou-se segura e eficaz, além de ser equivalente ao Onyx LES em relação aos achados angiográficos e histopatológicos pós-procedimento.

Chemical hypermethioninemia in young mice: oxidative damage and reduction of antioxidant enzyme activity in brain, kidney, and liver.

High levels of methionine (Met) and its metabolites, such as methionine sulfoxide (MetO), found in hypermethioninemia, can be detrimental to the body; however, the underlying mechanisms are still uncertain. Using a recently standardized protocol, the aim of this study was to investigate the effects of chronic administration of Met and/or MetO on parameters of oxidative damage in the total brain, liver, and kidney of young mice. Swiss male mice were subcutaneously injected with Met and MetO at concentrations of 0.35-1.2 g/kg body weight and 0.09-0.3 g/kg body weight, respectively, from the 10th-38th day post-birth, while the control group was treated with saline solution. Results showed that Met and/or MetO caused an increase in reactive oxygen species (ROS) and lipoperoxidation, along with a reduction of superoxide dismutase (SOD) and catalase (CAT) activities in the brain. In the liver, Met and/or MetO enhanced ROS and nitrite levels, and reduced SOD, CAT, and delta aminolevulinic dehydratase activities. The effects on the kidney were an increase in ROS production and SOD activity, and a reduction in thiol content and CAT activity. These data demonstrated the contribution of redox imbalance to the systemic changes found in patients with hypermethioninemia. In conclusion, our findings may help future studies to better understand the pathophysiological mechanisms of hypermethioninemia as well as contribute to the search for new therapeutic agents for this pathology.

Time-dependent contraction of the SARS-CoV-2-specific T-cell responses in convalescent individuals.

Background: Adaptive immunity in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is decisive for disease control. Delayed activation of T cells is associated with a worse outcome in coronavirus disease 2019 (COVID-19). Although convalescent individuals exhibit solid T-cell immunity, to date, long-term immunity to SARS-CoV-2 is still under investigation. Objectives: We aimed to characterize the specific T-cell response on the basis of the in vitro recall of IFN-γ-producing cells to in silico-predicted peptides in samples from SARS-CoV-2 convalescent individuals. Methods: The sequence of the SARS-CoV-2 genome was screened, leading to the identification of specific and promiscuous peptides predicted to be recognized by CD4+ and CD8+ T cells. Next, we performed an in vitro recall of specific T cells from PBMC samples from the participants. The results were analyzed according to clinical features of the cohort and HLA diversity. Results: Our results indicated heterogeneous T-cell responsiveness among the participants. Compared with patients who exhibited mild symptoms, hospitalized patients had a significantly higher magnitude of response. In addition, male and older patients showed a lower number of IFN-γ-producing cells. Analysis of samples collected after 180 days revealed a reduction in the number of specific circulating IFN-γ-producing T cells, suggesting decreased immunity against viral peptides. Conclusion: Our data are evidence that in silico-predicted peptides are highly recognized by T cells from convalescent individuals, suggesting a possible application for vaccine design. However, the number of specific T cells decreases 180 days after infection, which might be associated with reduced protection against reinfection over time.

Mathematical and Pharmacokinetic Approaches for the Design of New 3D Printing Inks Using Ricobendazole.

PURPOSE: 3D printing (3DP) makes it possible to obtain systems that are not achievable with current conventional methods, one of them, sustained release floating systems. Floating systems using ricobendazole (RBZ) as a model drug and a combination of polymers were designed and obtained by melt solidification printing technique (MESO-PP). METHODS: Four different MESO-PP inks were formulated based on combinations of the polymers Gelucire 43/01 and Gelucire 50/13 in different ratios. For each of the formulated inks, physicochemical characterization was performed by thermal analysis (thermogravimetric analysis [TGA] and differential scanning calorimetry [DSC]), fourier transform infrared spectrophotometer (FTIR) and X-ray diffraction (XRD). Pharmaceutical characterization was performed by in vitro assays to determine pharmaceutically relevant parameters. These parameters were calculated by applying mathematical models developed to evaluate in vitro drug release profiles. On the other hand, a physiologically based pharmacokinetic (PBPK) model was developed to predict the in vivo performance of RBZ loaded in the different inks by determining the Cmax, and the AUC0-∞. RESULTS: By increasing the proportion of Gelucire 50/13 co-surfactant in the mixtures (the proportion in Ink 1 was 33%, while the proportion in Ink 4 was 80%), the dissolution capacity of RBZ increases substantially, decreasing flotation times. CONCLUSION: MESO-PP produced ink 1 (50% Gelucire 43/01, 25% Gelucire 50/13 and 25% RBZ), which has a zero-order release (RR = 0.180%/min) and the longest flotation time (545 ± 23 min), and in turn would produce a significant increase in oral absorption of the drug, with an AUC0-∞ 2.16-fold higher than that obtained in animals treated with RBZ loaded in conventional tablets.

Dietary olive oil intake aggravates psoriatic skin inflammation in mice via Nrf2 activation and polyunsaturated fatty acid imbalance.

Psoriasis is a chronic inflammatory skin disease, which does not have effective treatment options. However, olive oil has been suggested as an alternative to treat psoriasis, but no study has evaluated the mechanisms involved in the effects of olive oil on psoriasis. Thus, the current study investigated whether olive oil could ameliorate psoriasiform skin inflammation. To test this, mice received topical application of imiquimod to induce inflammation and were treated orally with olive oil. Human immortalized keratinocytes were also treated with imiquimod and olive oil. Epidermal thickness and keratinocyte proliferation were increased in imiquimod-induced lesions of olive-oil-treated animals. In both in vitro and in vivo studies, protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) were elevated following imiquimod and olive oil administration. Inhibition of Nrf2 abolished the increased proliferation of keratinocytes treated with imiquimod and olive oil, demonstrating the role of Nrf2 in olive oil-mediated exacerbation of psoriasiform skin inflammation. In addition, lower levels of linoleic acid and higher levels of oleic acid were observed in imiquimod- and olive-oil-treated animals, which may also contribute to the adverse effects of olive oil on psoriasis. In conclusion, dietary intake of olive oil aggravates the symptoms of psoriatic skin lesions through the overexpression of Nrf2 and an imbalance in oleic and linoleic acids levels, suggesting that a diet rich in olive oil may have significant negative effects on psoriasis.

Phytomodulatory proteins isolated from Calotropis procera latex promote glycemic control by improving hepatic mitochondrial function in HepG2 cells.

The medicinal uses of Calotropis procera are diverse, yet some of them are based on effects that still lack scientific support. Control of diabetes is one of them. Recently, latex proteins from C. procera latex (LP) have been shown to promote in vivo glycemic control by the inhibition of hepatic glucose production via AMP-activated protein kinase (AMPK). Glycemic control has been attributed to an isolated fraction of LP (CpPII), which is composed of cysteine peptidases (95%) and osmotin (5%) isoforms. Those proteins are extensively characterized in terms of chemistry, biochemistry and structural aspects. Furthermore, we evaluated some aspects of the mitochondrial function and cellular mechanisms involved in CpPII activity. The effect of CpPII on glycemic control was evaluated in fasting mice by glycemic curve and glucose and pyruvate tolerance tests. HepG2 cells was treated with CpPII, and cell viability, oxygen consumption, PPAR activity, production of lactate and reactive oxygen species, mitochondrial density and protein and gene expression were analyzed. CpPII reduced fasting glycemia, improved glucose tolerance and inhibited hepatic glucose production in control animals. Additionally, CpPII increased the consumption of ATP-linked oxygen and mitochondrial uncoupling, reduced lactate concentration, increased protein expression of mitochondrial complexes I, III and V, and activity of peroxisome-proliferator-responsive elements (PPRE), reduced the presence of reactive oxygen species (ROS) and increased mitochondrial density in HepG2 cells by activation of AMPK/PPAR. Our findings strongly support the medicinal use of the plant and suggest that CpPII is a potential therapy for prevention and/or treatment of type-2 diabetes. A common epitope sequence shared among the proteases and osmotin is possibly the responsible for the beneficial effects of CpPII.

Thiamine deficiency and recovery: impact of recurrent episodes and beneficial effect of treatment with Trolox and dimethyl sulfoxide.

At present, thiamine deficiency (TD) is managed with administration of high doses of thiamine. Even so, severe and permanent neurological disorders can occur in recurrent episodes of TD. In this study, we used a murine model to assess the efficacy of TD recovery treatments using thiamine with or without additional administration of the antioxidant Trolox or the anti-inflammatory dimethyl sulfoxide (DMSO) after a single or recurrent episode of TD. TD was induced for 9 days with deficient chow and pyrithiamine, and the recovery period was 7 days with standard amounts of chow and thiamine, Trolox, and/or DMSO. After these periods, we evaluated behavior, histopathology, and ERK1/2 modulation in the brain. Deficient animals showed reductions in locomotor activity, motor coordination, and spatial memory. Morphologically, after a single episode of TD and recovery, deficient mice showed neuronal vacuolization in the dorsal thalamus and, after two episodes, a reduction in neuronal cell number. These effects were attenuated or reversed by the recovery treatments, mainly in the treatments with thiamine associated with Trolox or DMSO. Deficient animals showed a strong increase in ERK1/2 phosphorylation in the thalamus, hippocampus, and cerebral cortex after one deficiency episode and recovery. Interestingly, after recurrent TD and recovery, ERK1/2 phosphorylation remained high only in the deficient mice treated with thiamine and/or Trolox or thiamine with DMSO. Our data suggest that a protocol for TD treatment with thiamine in conjunction with Trolox or DMSO enhances the recovery of animals and possibly minimizes the late neurological sequelae.

Toxicity evaluation of Eleutherine plicata Herb. extracts and possible cell death mechanism.

Eleutherine plicata has been shown to be a promising medicinal plant, and its activity has been associated with naphthoquinones. The present study aimed at evaluating the cytotoxicity, genotoxicity, and oral toxicity of the ethanol extract (EEEp), dichloromethane fraction (FDMEp) of E. plicata, and isoeleutherin. For the cytotoxicity evaluation, the viability test (MTT) was used. Genotoxicity was accessed through the Comet assay (alkaline version), acute and subacute oral toxicities were also evaluated. The antioxidant capacity of the samples in the wells where the cells were treated with E. plicata was evaluated. Furthermore, the participation of caspase-8 in the possible mechanism of action of isoeleutherin, eleutherin, and eleutherol was also investigated through a docking study. FDMEp and isoeleutherin were cytotoxic, with higher rates of DNA fragmentation observed for FDMEp and isoeleutherin, and all samples displayed higher antioxidant potential than the control. In the acute oral toxicity test, EEEp, FDMEp, and isoeleutherin did not cause significant clinical changes. In the subacute toxicity assay, EEEp and FDMEp also did not cause clinical, hematological, or biochemical changes. The three compounds bound similarly to caspase-8. Despite the results of cytotoxicity, in vitro studies demonstrated that the use of EEEp appears to be safe and cell death may involve its binding to caspase-8.

S-methyl cysteine sulfoxide mitigates histopathological damage, alleviate oxidative stress and promotes immunomodulation in diabetic rats.

OBJECTIVES: S-methyl cysteine sulfoxide (SMCS) is a hydrophilic cysteine-containing natural compound found in plants and is known to possess antidiabetic and antioxidant properties. We investigated the antioxidant and immunomodulatory properties of SMCS, as well as histopathological changes in the liver and pancreas in streptozotocin (STZ)-induced diabetic rats. METHODS: The rats were divided into the following groups: control (CG), comprising non-diabetic rats; STZ-DB, comprising STZ-induced diabetic rats; and STZ-SMCS, comprising STZ-induced diabetic rats treated with SMCS. SMCS (200 mg/kg) was administered by gavage daily for 30 days. Biochemical and cytokine analyses, catalase (CAT) and superoxide dismutase (SOD) activities assays and histopathological analysis of liver and pancreas tissues were performed. RESULTS: SMCS treatment reduced glycemia (p<0.05), decreased triglyceride (p<0.01) and very-low-density lipoprotein (VLDL) levels (p<0.01), and increased SOD and CAT activity in the liver (both p<0.01) compared with STZ-DB group. Higher activity values of IL-10 were observed in the STZ-SMCS group than in the other groups (p<0.001). Liver glycogen was significantly improved in the STZ-SMCS group compared with the STZ-DB group. SMCS also ameliorated damage to pancreatic islets, which resulted in restoration of their morphology. CONCLUSIONS: Oral treatment of SMCS showed improvement of the morphological alterations in liver and pancreatic islet in diabetic rats. These beneficial morphological effects of SMCS can be partially explained by IL-10 modulation associated with antioxidant action.

Acute hypermethioninemia impairs redox homeostasis and acetylcholinesterase activity in the hippocampus, striatum, and cerebellum of young rats.

Hypermethioninemia is characterized by high plasma concentrations of methionine (Met) and its metabolites, such as methionine sulfoxide (MetO), and neurological changes, such as cerebral edema and cognitive deficits. The aim of this study was to analyze the redox status and acetylcholinesterase (AChE) activity in the hippocampus, striatum, and cerebellum of young Wistar rats subjected to an acute hypermethioninemia protocol. The animals received, by subcutaneous injection, a single dose of Met (0.4 g/kg), MetO (0.1 g/kg), and Met + MetO, and 1 or 3 hr after administration, the animals were euthanatized for brain structure obtaining. In the hippocampus, an increase in lipid peroxidation and glutathione peroxidase (GPx) activity was observed at 1 hr in the MetO and Met + MetO groups, and a reduction in the superoxide dismutase activity was found in the Met + MetO group. Met and/or MetO induced a decrease in the thiol content and GPx activity and enhanced the lipid peroxidation at 3 hr. In the striatum, a reduction in the thiol content and GPx activity, an increase in lipid peroxidation, and AChE activity were induced by Met and/or MetO at 1 or 3 hr. Additionally, in the cerebellum, an increase in the AChE in the MetO and Met + MetO groups 1 hr after administration was observed. These data help to better understand the pathophysiological mechanisms that underlie the neurological changes found in hypermethioninemia patients.

Determination of chemical structure and anti-Trypanosoma cruzi activity of extracts from the roots of Lonchocarpus cultratus (Vell.) A.M.G. Azevedo & H.C. Lima.

Trypanosoma cruzi is the agent of Chagas disease, an infection that affects around 8 million people worldwide. The search for new anti-T. cruzi drugs are relevant, mainly because the treatment of this disease is limited to two drugs. The objective of this study was to investigate the trypanocidal and cytotoxic activity and elucidate the chemical profile of extracts from the roots of the Lonchocarpus cultratus. Roots from L. cultratus were submitted to successive extractions with hexane, dichloromethane, and methanol, resulting in LCH, LCD, and LCM extracts, respectively. Characterization of extracts was done using 1H-RMN, 13C-RMN, CC and TLC. Treatment of T. cruzi forms (epimastigotes, trypomastigotes, and amastigotes) with crescent concentrations of LCH, LCD, and LCM was done for 72, 48, and 48 h, respectively. After this, the percentage of inhibition and IC50/LC50 were calculated. Benznidazole was used as a positive control. Murine macrophages were treated with different concentrations of both extracts for 48 h, and after, the cellular viability was determined by the MTT method and CC50 was calculated. The chalcones derricin and lonchocarpine were identified in the hexane extract, and for the first time in the genus Lonchocarpus, the presence of a dihydrolonchocarpine derivative was observed. Other chalcones such as isocordoin and erioschalcone B were detected in the dichloromethane extract. The dichloromethane extract showed higher activity against all tested forms of T. cruzi than the other two extracts, with IC50 values of 10.98, 2.42, and 0.83 µg/mL, respectively; these values are very close to those of benznidazole. Although the dichloromethane extract presented a cytotoxic effect against mammalian cells, it showed selectivity against amastigotes. The methanolic extract showed the lowest anti-T. cruzi activity but was non-toxic to peritoneal murine macrophages. Thus, the genus Lonchocarpus had demonstrated in the past action against epimastigotes forms of T. cruzi but is the first time that the activity against infective forms is showed, which leading to further studies with in vivo tests.

Functional characterization of methionine sulfoxide reductases from Leptospira interrogans.

BACKGROUND: Methionine (Met) oxidation leads to a racemic mixture of R and S forms of methionine sulfoxide (MetSO). Methionine sulfoxide reductases (Msr) are enzymes that can reduce specifically each isomer of MetSO, both free and protein-bound. The Met oxidation could change the structure and function of many proteins, not only of those redox-related but also of others involved in different metabolic pathways. Until now, there is no information about the presence or function of Msrs enzymes in Leptospira interrogans. METHODS: We identified genes coding for putative MsrAs (A1 and A2) and MsrB in L. interrogans serovar Copenhageni strain Fiocruz L1-130 genome project. From these, we obtained the recombinant proteins and performed their functional characterization. RESULTS: The recombinant L. interrogans MsrB catalyzed the reduction of Met(R)SO using glutaredoxin and thioredoxin as reducing substrates and behaves like a 1-Cys Msr (without resolutive Cys residue). It was able to partially revert the in vitro HClO-dependent inactivation of L. interrogans catalase. Both recombinant MsrAs reduced Met(S)SO, being the recycle mediated by the thioredoxin system. LinMsrAs were more efficient than LinMsrB for free and protein-bound MetSO reduction. Besides, LinMsrAs are enzymes involving a Cys triad in their catalytic mechanism. LinMsrs showed a dual localization, both in cytoplasm and periplasm. CONCLUSIONS AND GENERAL SIGNIFICANCE: This article brings new knowledge about redox metabolism in L. interrogans. Our results support the occurrence of a metabolic pathway involved in the critical function of repairing oxidized macromolecules in this pathogen.

Cellulose Dissolution in Mixtures of Ionic Liquids and Dimethyl Sulfoxide: A Quantitative Assessment of the Relative Importance of Temperature and Composition of the Binary Solvent.

We studied the dissolution of microcrystalline cellulose (MCC) in binary mixtures of dimethyl sulfoxide (DMSO) and the ionic liquids: allylbenzyldimethylammonium acetate; 1-(2-methoxyethyl)-3-methylimidazolium acetate; 1,8-diazabicyclo [5.4.0]undec-7-ene-8-ium acetate; tetramethylguanidinium acetate. Using chemometrics, we determined the dependence of the mass fraction (in %) of dissolved cellulose (MCC-m%) on the temperature, T = 40, 60, and 80 °C, and the mole fraction of DMSO, χDMSO = 0.4, 0.6, and 0.8. We derived equations that quantified the dependence of MCC-m% on T and χDMSO. Cellulose dissolution increased as a function of increasing both variables; the contribution of χDMSO was larger than that of T in some cases. Solvent empirical polarity was qualitatively employed to rationalize the cellulose dissolution efficiency of the solvent. Using the solvatochromic probe 2,6-dichloro-4-(2,4,6-triphenylpyridinium-1-yl)phenolate (WB), we calculated the empirical polarity ET(WB) of cellobiose (a model for MCC) in ionic liquid (IL)-DMSO mixtures. The ET(WB) correlated perfectly with T (fixed χDMSO) and with χDMSO (fixed T). These results show that there is ground for using medium empirical polarity to assess cellulose dissolution efficiency. We calculated values of MCC-m% under conditions other than those employed to generate the statistical model and determined the corresponding MCC-m% experimentally. The excellent agreement between both values shows the robustness of the statistical model and the usefulness of our approach to predict cellulose dissolution, thus saving time, labor, and material.