Identification of purinergic system components in the venom of Bothrops mattogrossensis and the inhibitory effect of specioside extracted from Tabebuia aurea.

Snake bites are a severe problem in the countryside of Brazil and are usually attributed to snakes of the genera Bothrops, Crotalus, and Lachesis. Snake venom can release ectoenzymes and nucleotidases that modulate the purinergic system. In addition to serum therapy against snake poisoning, medicinal plants with anti-inflammatory activities, such as Tabebuia aurea, is empirically applied in accidents that occur in difficult-to-access areas. This study aimed was to verify the presence and activity of nucleotidases in the crude venom of Bothrops mattogrossensis (BmtV) in vitro and characterize the modulation of purinergic components, myeloid differentiation, and inflammatory/oxidative stress markers by BmtV in vivo and in vitro. Moreover, our study assessed the inhibitory activities of specioside, an iridoid isolated from Tabebuia aurea, against the effects of BmtV. Proteomic analysis of venom content and nucleotidase activity confirm the presence of ectonucleotidase-like enzymes in BmtV. In in vivo experiments, BmtV altered purinergic component expression (P2X7 receptor, CD39 and CD73), increased neutrophil numbers in peripheral blood, and elevated oxidative stress/inflammatory parameters such as lipid peroxidation and myeloperoxidase activity. BmtV also decreased viability and increased spreading index and phagocytic activity on macrophages. Specioside inhibited nucleotidase activity, restored neutrophil numbers, and mediate the oxidative/inflammatory effects produced by BmtV. We highlight the effects produced by BmtV in purinergic system components, myeloid differentiation, and inflammatory/oxidative stress parameters, while specioside reduced the main BmtV-dependent effects.

Effects of urban streams on muscle non-protein thiols, gill and liver histopathology in zebrafish (Danio rerio) assessed by active biomonitoring.

Aquatic biota are exposed to toxic substances resulting from human activities, reducing environmental quality and can compromise the health of the organisms. This study aimed to employ Danio rerio as an environmental bioindicator, analyzing the effects of water from distinct urban aquatic environments. An active biomonitoring system was set up to compare the temporal dynamics of histological biomarkers for gill and liver and the patterns of non-protein thiols (NPSH) in muscle in specimens exposed for 3, 6, and 12 days. Three large urban basins in the city of Campo Grande (Midwest of Brazil) were selected. Two sites are in a very populous area (i.e Lagoa and Bandeira) and another on in an area with agricultural activities (i.e Anhanduí). All the streams displayed distinct qualitative characteristics. The presence of metals, including Mn, Zn, Fe, and Al, as well as pH, temperature, and dissolved oxygen, accounted for 38% of the variability (PC1), while total solids, conductivity, ammonia, nitrite, and explained 24 % (PC2). Degree tissue changes index (DTC) in gill and the concentration of NPSH increased in all streams during 3, 6 and 12 days of exposure. DTC in liver increases in all exposure times in most populous stream (i.e Lagoa and Bandeira). Histopathological evidence in the gill, including proliferation, desquamation, and necrosis of the primary lamellar epithelium; fusion and aneurysms in the secondary lamellar epithelium were observed after three days of exposure. Degenerative nuclear figures were noted in the liver after three days of exposure, followed by hepatocellular hypertrophy, lipidosis, and necrosis at twelve days. Our findings showing time-dependent effects of urban aquatic environments in histopathological (i.e DTC) and biochemical biomarkers in zebrafish. The biomonitoring model enabled a comparison of the temporal dynamics of various health markers, using zebrafish as bioindicator. Future studies might use this experimental model and biomarkers for environmental biomonitoring program.

Cytogenotoxic potential and toxicity in adult Danio rerio (zebrafish) exposed to chloramine T.

Background: Chloramine-T (CL-T) is a synthetic sodium salt used as a disinfectant in fish farms to combat bacterial infections in fish gills and skin. While its efficacy in pathogen control is well-established, its reactivity with various functional groups has raised concerns. However, limited research exists on the toxicity of disinfection by-products to aquatic organisms. Therefore, this study aims to assess the sublethal effects of CL-T on adult zebrafish by examining biomarkers of nucleus cytotoxicity and genotoxicity, acetylcholinesterase (AChE) inhibition, and histopathological changes. Methods: Male and female adult zebrafish (wildtype AB lineage) specimens were exposed to 70, 140, and 200 mg/L of CL-T and evaluated after 96 h. Cytotoxic and genotoxic effects were evaluated by estimating the frequencies of nuclear abnormalities (NA), micronuclei (MN), and integrated optical density (IOD) of nuclear erythrocytes. Histopathological changes in the gills and liver were assessed using the degree of tissue changes (DTC). AChE activity was measured in brain samples. Results and conclusions: At a concentration of 200 mg/L, NA increased, indicating the cytogenotoxic potential of CL-T in adult zebrafish. Morphological alterations in the nuclei were observed at both 70 and 200 mg/L concentrations. Distinct IOD profiles were identified across the three concentrations. There were no changes in AChE activity in adult zebrafish. The DTC scores were high in all concentrations, and histological alterations suggested low to moderate toxicity of CL-T for adult zebrafish.

Effects of Chloramine T on zebrafish embryos malformations associated with cardiotoxicity and neurotoxicity.

Chloramine T, a sodium p-toluene sulfonchloramide, is known to possess a wide spectrum of biocidal activity and is employed as a disinfectant in fish farms to treat bacterial infections. Although Chloramine T may effectively combat pathogens, the sublethal and lethal effects and changes in acetylcholinesterase (AChE) activity remain poorly elucidated using Danio rerio (zebrafish) embryos. Zebrafish is considered a model organism for toxicant screening research and exhibits mammalian-like physiological responses when exposed to environmental pollutants. The aim of this study was to (1) determine LC50 of Chloramine T after 96 hr exposure, (2) verify disinfectant effects on developmental morphology, and (3) evaluate the disinfectant effects on AChE activity in zebrafish embryos. Chloramine T exposure was performed using 16, 32, 64, 128, or 256 mg/L concentrations. The mortality LC50 values were 143.05 ± 3.11 and 130.97 ± 7.4 mg/L at 24 and 96 hr, respectively. Data demonstrated delayed hatching, reduced heartbeats, cardiac edema, and equilibrium disruption of hatched larvae throughout embryonic development. In addition, Chloramine T inhibited AChE activity at 64 or 128 mg/L after 96 hr treatment, corroborating the sub-lethality results observed in zebrafish embryo development and demonstrating an equilibrium disruption in zebrafish larvae.

l-Hypaphorine and d-hypaphorine: Specific antiacetylcholinesterase activity in rat brain tissue.

Acetylcholinesterase (AChEis) inhibitors are used to treat neurodegenerative diseases like Alzheimer's disease (AD). l-Hypaphorine (l-HYP) is a natural indole alkaloid that has been shown to have effects on the central nervous system (CNS). The goal of this research was to synthesize l-HYP and d-HYP and test their anticholinesterasic properties in rat brain regions. l-HYP suppressed acetylcholinesterase (AChE) activity only in the cerebellum, whereas d-HYP inhibited AChE activity in all CNS regions studied. No cytotoxic effect on normal human cells (HaCaT) was observed in the case of l-HYP and d-HYP although an increase in cell proliferation. Molecular modeling studies revealed that d-HYP and l-HYP have significant differences in their binding mode positions and interact stereospecifically with AChE's amino acid residues.

Osmoregulatory profiles and gill histological changes in Nile tilapia (Oreochromis niloticus) exposed to lambda-cyhalothrin.

Lambda-cyhalothrin is a synthetic pyrethroid that mimics the structure and insecticidal properties of pyrethrin, a natural insecticide derived from chrysanthemums. In fish, it disrupts the nervous system, causing motor paralysis and several other alterations associated with varying levels of mortality. This study aimed to evaluate osmoregulatory responses and histological changes in the gills of Oreochromis niloticus chronically exposed to a sublethal dosage (0.86 µg/L) of lambda-cyhalothrin. The mean serum values for Na2+, K+, Cl-, Ca2+, pH, lactate, H+, HCO3, and glucose along to degree of tissue change (DTC) at 24, 96, 168, and 240 h post-exposure (hpe) were evaluated. Lambda-cyhalothrin affected the neuronal motor function at 24 hpe, followed by the increase of the K+, Ca2+, H+, and glucose levels in the exposed group, compared to the control group. Lactate and H+ levels in the exposed group were higher than those in the control group at 168 and 240 hpe respectively. HCO3, and Cl- levels increased at 240 hpe, although there was no change in the pH values. DTC was higher in treated fish than in control fish, but there were no significant differences among time-exposure. The changes detected ranged from hyperemia of the branchial vasculature, eosinophilic granulocytic cell infiltration, mucous cell hyperplasia, and partial fusion of secondary lamellae at 24 hpe to vascular aneurysm formation, and necrosis of the lamellar epithelium at 240 hpe. Thus, a sublethal dosage of lambda-cyhalothrin in the long-term is toxic for Nile tilapia, characterized by hypokalemia, hypercalcemia, hyperglycemia, and respiratory alkalosis, followed by time-dependent histological changes.

Protective Effect of α-Linolenic Acid on Non-Alcoholic Hepatic Steatosis and Interleukin-6 and -10 in Wistar Rats.

Consumption of omega-3 (n-3) polyunsaturated fatty acids (PUFA) is related to improvement in the inflammatory response associated with decreases in metabolic disorders of obesity, such as low-grade inflammation and hepatic steatosis. Linseed (Linum usitatissimum) oil is a primary source of n-3 fatty acids (FAs) of plant origin, particularly α-linolenic acid, and provides an alternative for the ingestion of n-3 PUFA by persons allergic to, or wishing to avoid, animal sources. In our study, we evaluated the effect of the consumption of different lipidic sources on metabolic and inflammatory parameters in Wistar rats. We split 56 male rats into four groups that were fed for 60 days with the following diets: sesame oil, (SO, Sesamum indicum), linseed oil (LO), SO + LO (SLO), and a control group (CG) fed with animal fat. Our results reveal that the use of LO or SLO produced improvements in the hepatic tissue, such as lower values of aspartate aminotransferase, liver weight, and hepatic steatosis. LO and SLO reduced the weight of visceral fats, weight gain, and mediated the inflammation through a decrease in interleukin (IL)-6 and increase in IL-10. Though we did not detect any significant differences in the intestine histology and the purinergic system enzymes, the consumption of α-linolenic acid appears to contribute to the inflammatory and hepatic modulation of animals compared with a diet rich in saturated FAs and or unbalanced in n-6/n-3 PUFAs, inferring possible use in treatment of metabolic disorders associated with obesity and cardiovascular diseases.

Assessment of acute toxicity and cytotoxicity of fluorescent markers produced by cardanol and glycerol, which are industrial waste, to different biological models.

The amphyphylic triazoanilines recently synthesized 1-(4-(3-aminophenyl)-1H-1,2,3- triazole-1-yl)-3-(3-pentadecylphenoxy)propan-2-ol (1) and 1-(4-(4-aminophenyl)-1H- 1,2,3-triazole-1-yl)-3-(3-pentadecylphenoxy)propan-2-ol (2), synthesized from cardanol and glycerol, have photophysical properties which allow their use in the development of fluorescent biomarkers with applicability in the biodiesel quality control. Based on this, the present research evaluated the toxic effects of both compounds in different biological models through the investigation of survival and mortality percentages as a measure of acute toxicity on Daphnia similis and Oreochromis niloticus, larvicidal assay against Aedes aegypti, and cytotoxic activity on mammary cells. Results demonstrate that these triazoanilines 1 and 2 have shown low acute toxicity to the biological models investigated in this study up to the following concentrations: 4.0 mg L-1 (D. similis), 4.0 mg L-1 (A. aegypti larvae), 1.0 mg L-1 (O. niloticus), and 1.0 mg mL-1 (mammary cells). This fact suggests the potential for safe use of compounds 1 and 2 as fluorescent markers for the monitoring of biodiesel quality, even in the case of environmental exposure. Besides all of that, the reuse of cardanol and glycerol, both industrial wastes, favors the maintenance of environmental health and is in agreement with the assumptions of green chemistry. Graphical abstract ᅟ.

Effect of Acrocomia aculeata Kernel Oil on Adiposity in Type 2 Diabetic Rats.

The macauba palm (Acrocomia aculeata) is native of tropical America and is found mostly in the Cerrados and Pantanal biomes. The fruits provide an oily pulp, rich in long chain fatty acids, and a kernel that encompass more than 50% of lipids rich in medium chain fatty acids (MCFA). Based on biochemical and nutritional evidences MCFA is readily catabolized and can reduce body fat accumulation. In this study, an animal model was employed to evaluate the effect of Acrocomia aculeata kernel oil (AKO) on the blood glucose level and the fatty acid deposit in the epididymal adipose tissue. The A. aculeata kernel oil obtained by cold pressing presented suitable quality as edible oil. Its fatty acid profile indicates high concentration of MCFA, mainly lauric, capric and caprilic. Type 2 diabetic rats fed with that kernel oil showed reduction of blood glucose level in comparison with the diabetic control group. Acrocomia aculeata kernel oil showed hypoglycemic effect. A small fraction of total dietary medium chain fatty acid was accumulated in the epididymal adipose tissue of rats fed with AKO at both low and high doses and caprilic acid did not deposit at all.

Characterization of ectonucleoside triphosphate diphosphohydrolase (E-NTPDase; EC 3.6.1.5) activity in mouse peritoneal cavity cells.

This study aimed to characterize the activity of ectonucleoside triphosphate diphosphohydrolase (E-NTPDase; EC 3.6.1.5) in peritoneal cavity cells from BALB/c mice. E-NTPDase was activated in the presence of both calcium (1.5mM) and magnesium (1.5mM) ions. However, the activity was higher in the presence of Ca2+ . A pH of 8.5 and temperature of 37°C were the optimum conditions for catalysis. The apparent Km values were 0.51mM and 0.66mM for the hydrolysis of adenosine triphosphate (ATP) and adenosine diphosphate (ADP), respectively. The Vmax values were 136.4 and 120.8 nmol Pi/min/mg of protein for ATPase and ADPase activity, respectively. Nucleotide hydrolysis was inhibited in the presence of sodium azide (20mM, ATP: P < .05; ADP: P < .001), sodium fluoride (20mM; ATP and ADP: P < .001), and suramin (0.3mM; ATP: P < .01; ADP: P < .05), which is a known profile for NTPDase inhibition. Although all of the diphosphate and triphosphate nucleotides that were tested were hydrolyzed, enzyme activity was increased when adenine nucleotides were used as substrates. Finally, we stress that knowledge of the E-NTPDase catalytic biochemical properties in mouse peritoneal cavity cells is indispensable for properly determining its activity, as well as to fully understand the immune response profile in both healthy and sick cells.

Evaluation of P2X7 receptor expression in peripheral lymphocytes and immune profile from patients with indeterminate form of Chagas disease.

Chagas disease (CD) is caused by Trypanosoma cruzi, an intracellular protozoan which is a potent stimulator of cell-mediated immunity. In the indeterminate form of CD (IFCD) a modulation between pro- and anti-inflammatory responses establishes a host-parasite adaptation. It was previously demonstrated that purinergic ecto-enzymes regulates extracellular ATP and adenosine levels, influencing immune and inflammatory processes during IFCD. In inflammatory sites ATP, as well as its degradation product, adenosine, function as signaling molecules and immunoregulators through the activation of purinergic receptors. In this work, it was analyzed the gene and protein expression of P2X7 purinergic receptor in peripheral lymphocytes and serum immunoregulatory cytokines from IFCD patients. Gene and protein expression of P2X7 receptor (P2X7R), and serum cytokines (IL-2, IL-10, IL-17 and IFN-γ) were unaltered. However, IFCD group showed significantly higher IL-4 and IL-6 levels while TNF-α was significantly decreased. These results indicate that imune profile of IFCD patients displays anti-inflammatory characteristics, consistent with the establishment of an immunomodulatory response. Further study about the molecular knowledge of P2X7R in IFCD is useful to clarify the participation of purinergic system in the regulatory mechanism which avoid the progression of CD.

Oxidative stability of sesame and flaxseed oils and their effects on morphometric and biochemical parameters in an animal model.

BACKGROUND: Sesame and flaxseed oils, which are rich in essential n-6 and n-3 polyunsaturated fatty acids, are widely consumed. We have determined the optical behavior with respect to the quality and identity of cold-pressed sesame and flaxseed oils. The effects of these oils and their combinations on metabolic parameters in animal models were also measured. RESULTS: Flaxseed oil emitted carotenoid fluorescence (500-650 nm), although it was more unstable than sesame oil, which had a larger induction period by the Rancimat method. The greater stability of sesame may be a result of the lower quantity of linolenic fatty acids. These oils were added to the feed of 56 rats, whereas animal fat was used for the control group. The sesame oil, flaxseed oil and sesame + flaxseed oils groups showed a significantly reduced adiposity index and blood glucose compared to the control group, whereas total cholesterol, high-density lipoprotein and triglycerides were lower in flaxseed oil and sesame + flaxseed oils (P < 0.05). Sesame + flaxseed oils had reduced levels of low-density lipoprotein and non-high-density lipoprotein (P < 0.05), indicating an anti-atherogenic effect in this group. CONCLUSION: Sesame oil was more stable than flaxseed oil. In an animal model, the diets with polyunsaturated fat sources proportions of 1:1 n-6:n-3 polyunsaturated fatty acids, improved the metabolic parameters, implying cardioprotective effects. © 2016 Society of Chemical Industry.

Effects of chlorogenic acid on adenine nucleotides hydrolyzing enzyme activities and expression in platelets of rats experimentally demyelinated with ethidium bromide.

BACKGROUND: The effects of chlorogenic acid (one of the major phenolic acid found in human diets) were investigated on the adenine nucleotides hydrolyzing enzymes; ecto-nucleotide pyrophosphatase/phophodiesterase (E-NPP), ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), E-5'- nucleotidase and ecto-adenosine deaminase (E-ADA) activities and expression in platelets of rats experimentally demyelinated with ethidium bromide. METHODS: Rats were divided into four groups of eight animals each. Group I rats were control rats; injected with saline (CT), group II rats were injected with saline and treated with chlorogenic acid (AC), group III rats were injected with 0.1% ethidium bromide (EB) and group IV rats were injected with 0.1% EB and treated with chlorogenic acid (EB+AC). The activities of the enzymes were analyzed using colorimetric methods, and the gene expression of NTPDase 1, 2 and 3 were analyzed using the polymerase chain reaction (PCR). RESULTS: The results revealed that there was a significant (P<0.01) reduction in E-NPP activity in EB group (1.63±0.10nmol p-nitrophenol released/min/mg protein) when compared to CT group (2.33±0.14nmol p-nitrophenol released/min/mg protein). However, treatment with chlorogenic acid significantly (P<0.05) increased E-NPP activity in EB group. Furthermore, no significant (P>0.05) change was observed in the E-NPP activity of EB+AC group (2.19±0.08nmol p-nitrophenol released/min/mg protein) when compared to CT group (2.33±0.14nmol p-nitrophenol released/min/mg protein). In addition, there was a significant (P<0.05) increase in AMP hydrolysis in EB rat group when compared to CT group. No significant (P>0.05) difference was observed in AMP hydrolysis between AC, AC+EB and CT groups. Conversely, there were no significant (P>0.05) differences in ATP and ADP hydrolyses between all the groups (AC, EB, AC+EB and CT groups). Likewise, there were no significant (P>0.05) changes in E-ADA activity and percentage platelet aggregation among all groups studied. Similarly, no significant (P>0.05) change was observed in the expression of E-NTPDase 1, 2 and 3 in all the groups tested. CONCLUSIONS: Our study revealed that chlorogenic acid may modulate the hydrolysis of adenine nucleotides in platelets of rats demyelinated and treated with chlorogenic acid via alteration of E-NPP and ecto-5'-nucleotidase activities.

Activity of cholinesterases, pyruvate kinase and adenosine deaminase in rats experimentally infected by Fasciola hepatica: Influences of these enzymes on inflammatory response and pathological findings.

The aim of this study was to investigate acetylcholinesterase (AChE) in total blood and liver tissue; butyrylcholinesterase (BChE) in serum and liver tissue; adenosine deaminase (ADA) in serum and liver tissue; and pyruvate kinase (PK) in liver tissue of rats experimentally infected by Fasciola hepatica. Animals were divided into two groups with 12 animals each, as follows: group A (uninfected) and group B (infected). Samples were collected at 20 (A1 and B1;n=6 each) and 150 (A2 and B2; n=6 each) days post-infection (PI). Infected animals showed an increase in AChE activity in whole blood and a decrease in AChE activity in liver homogenates (P<0.05) at 20 and 150 days PI. BChE and PK activities were decreased (P<0.05) in serum and liver homogenates of infected animals at 150 days PI. ADA activity was decreased in serum at 20 and 150 days PI, while in liver homogenates it was only decreased at 150 days PI (P<0.05). Aspartate aminotransferase and alanine aminotransferase activities in serum were increased (P<0.05), while concentrations of total protein and albumin were decreased (P<0.05) when compared to control. The histological analysis revealed fibrous perihepatitis and necrosis. Therefore, we conclude that the liver fluke is associated with cholinergic and purinergic dysfunctions, which in turn may influence the pathogenesis of the disease.

Oxidative stress associated with pathological lesions in the liver of rats experimentally infected by Fasciola hepatica.

The aim of this study was to analyze the antioxidant status and oxidative profile in serum and liver of rats experimentally infected with Fasciola hepatica and its relationship with pathological findings. Twenty-four rats were divided into two groups: group A consisted of 12 healthy rats and group B of 12 rats infected orally with 20 metacercaria of F. hepatica. At days 20 and 150 post-infection (PI), blood and liver samples of six animals from each group were collected. The protein oxidation (AOPP technique: advanced oxidation protein products) and antioxidants (FRAP technique: ferric reducing antioxidant power) levels were measured in serum and liver. Furthermore, nitrite/nitrate (NOx) levels and lipid peroxidation (TBARS technique: thiobarbituric acid reactive substances) were measured in liver. AOPP and FRAP levels were increased (P < 0.05) in serum and liver of infected animals in acute and chronic infection when compared with healthy animals. The same occurred with TBARS and NOx levels in the liver (P < 0.05). Histopathology revealed periportal fibrous hepatitis, composed of an abundant inflammatory infiltrate in portal spaces on infected animals, as well as bile duct hyperplasia. The results found seem to be related to the host free radical production demonstrated in serum samples and liver due to the parasite infection.

Oxidative stress and inflammatory response biomarkers in dogs with mammary carcinoma.

Mammary carcinoma is the most common cancer that affects dogs, and in many cases it leads to death. Thus, given the importance of this disease, to clarify its pathogenesis is an important measure. In this sense, the aim of this study was to investigate the levels of cytokines and nitric oxide (NO), oxidative and antioxidant status, as well as the activity of adenosine deaminase (ADA) and butyrylcholinesterase (BChE) in dogs diagnosed with mammary carcinoma. With this purpose, thirty-three (33) serum samples from female dogs with histopathological diagnosis of mammary carcinoma, without evidence of metastasis, were used (group B). The material was classified based on the degree of malignancy, as follows: subgroup B1 (low-grade malignancy; n=26) and subgroup B2 (high grade of malignancy; n=7). Serum samples from healthy females (group A; n=10) were used as negative control. Our results showed that levels of cytokines (TNF-α, INF-γ, IL-1, and IL-6), NOx (nitrite/nitrate), AOPP (protein oxidation), and FRAP (antioxidant power) were significantly (P<0.05) increased in dogs with mammary carcinoma (group B), when compared with group A. On the other hand, ADA activity was significantly decreased (P<0.05) in both subgroups B1 and B2, when compared with group A. BChE activity, however, was reduced (P<0.05) only in subgroup B2 when compared with group A and subgroup B1. Unlike other variables, NO, AOPP, and IFN-γ were influenced by the degree of tumor malignancy, i.e., their levels were even higher in subgroup B2. Therefore, based on these results, we can conclude that all variables investigated are related to the pathogenesis of this disease, since they were altered in dogs with mammary tumor. Additionally, we suggest that ADA activity had an anti-inflammatory effect on these tumor samples, probably in order to modulate the inflammatory response.

Effect of Uncaria tomentosa extract on purinergic enzyme activities in lymphocytes of rats submitted to experimental adjuvant arthritis model.

BACKGROUND: Considering that adjuvant arthritis is an experimental model of arthritis widely used for preclinical testing of numerous anti-arthritic agents, which were taken by a large number of patients worldwide, it is of great interest to investigate the therapeutic action of compounds with anti-inflammatory properties, such as Uncaria tomentosa extract. Moreover, there are no studies demonstrating the effect of U. tomentosa on the metabolism of adenine nucleotides published so far. Thus, the purpose of the present study is to investigate the effects of U. tomentosa extract on E-NTPDase and E-ADA activities in lymphocytes of Complete Freund's Adjuvant (CFA) arthritis induced rats. METHODS: To evaluate the effect of U. tomentosa extract on the activity of E-NTPDase and ADA in lymphocytes, the rats were submitted to an experimental adjuvant arthritis model. Peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Data were analyzed by a one- or two-way ANOVA. Post hoc analyses were carried out by the Student-Newman-Keuls (SNK) Multiple Comparison Test. RESULTS: E-NTPDase activity was increased in arthritic untreated. Arthritic rats which received U. tomentosa extract, presented similar results to the control group. However, results obtained for adenosine hydrolysis by E-ADA were not altered in arthritic rats. U. tomentosa extract did not alter E-NTPDase and E-ADA activity in healthy animals. CONCLUSIONS: The present investigation supports the hypothesis that the increased E-NTPDase activity verified in arthritic rats might be an attempt to maintain basal levels of ATP and ADP in the extracellular medium, since the arthritis induction causes tissue damage and, consequently, large amounts of ATP are released into this milieu. Also, it highlights the possibility to use U. tomentosa extract as an adjuvant to treat arthritis.

Swimming training prevents alterations in ecto-NTPDase and adenosine deaminase activities in lymphocytes from Nω-nitro-L-arginine methyl ester hydrochloride induced hypertension rats.

BACKGROUND AND METHOD: Hypertension is accompanied by inflammatory process and purinergic system has been recognized as having an important role in modulating immune functions. Physical training is being considered one of the major lifestyle changes that contributes to the cardiovascular health as well as has an important role in regulating purinergic system. Thus, the aim of this study was to investigate the effect of chronic swimming training on lymphocytic purinergic system enzymes activities related to inflammatory process, as well as in lipid profile and classic inflammatory markers in rats that developed hypertension in response to the oral administration of N-nitro-L-arginine methyl ester hydrochloride (L-NAME). RESULTS: After 6 weeks of training, lymphocytes and serum were separated to be analysed. L-NAME-treated group displayed an increase in SBP as well as in ecto-NTPDase and adenosine deaminase (ADA) activities (P < 0.05). Six weeks of swimming training were able to prevent these alterations and keep the blood pressure and enzymes activities in the same levels of control group. Exercise per se was associated with a decrease in the expression of ecto-NTPDase1 in lymphocytes (-23.4%). Exercise was also efficient in preventing the rise in classic inflammatory markers observed in L-NAME group. CONCLUSION: These findings highlight the link between purinergic signalling and inflammatory process and suggest a novel mechanism in which moderate aerobic exercise possesses the potential to attenuate inflammation caused by hypertension.

Individual in vitro effects of ochratoxin A, deoxynivalenol and zearalenone on oxidative stress and acetylcholinesterase in lymphocytes of broiler chickens.

The contamination of consumer food and animal feed with toxigenic fungi has resulted in economic losses worldwide in animal industries. Mycotoxins are highly biologically reactive secondary metabolites and can inhibit protein synthesis and cell multiplication. Considering the cytotoxicity of mycotoxins, this experiment was performed to determine the in vitro influence of ochratoxin A, deoxynivalenol and zearalenone on lipid peroxidation in lymphocytes of broiler chickens at different concentrations. This study has also evaluated whether the presence of these mycotoxins changes the acetylcholinesterase activity in lymphocytes, which is involved in the regulation of immune and inflammatory responses. Blood lymphocytes of broiler chickens were isolated through density gradient centrifugation and incubated with the respective mycotoxins at concentrations of 0.001, 0.01, 0.1 and 1 µg/mL. Lipid peroxidation, which was evaluated through the amount of malondialdehyde measured in a thiobarbituric acid-reactive species test, and the enzymatic activity were analyzed at 24, 48 and 72 h. Results of the lipid peroxidation evaluation showed an increasing cytotoxicity relation: ochratoxin A > deoxynivalenol > zearalenone. Conversely, cytotoxicity was valued as zearalenone > deoxynivalenol > ochratoxin A in relation to the acetylcholinesterase enzymatic activity. At a concentration of 1 µg/mL, ochratoxin A and deoxynivalenol induced the highest cellular oxidative stress levels and the highest enzymatic activity at the majority of time points. However, the same mycotoxins, except at 1 µg/mL concentration, induced a reduction of lymphocytic lipid peroxidation 72 h after incubation, suggesting the action of a compensatory mechanism in these cells.

Alterations in the extracellular catabolism of nucleotides and platelet aggregation induced by high-fat diet in rats: effects of alpha-tocopherol

The aim of this study was to assess whether alfa-tocopherol administration prevented alterations in the ectonucleotidase activities and platelet aggregation induced by high-fat diet in rats. Thus, we examined four groups of male rats which received standard diet, high-fat diet (HFD), α-tocopherol (α-Toc), and high-fat diet plus α-tocopherol. HFD was administered ad libitum and α-Toc by gavage using a dose of 50 mg/kg. After 3 months of treatment, animals were submitted to euthanasia, and blood samples were collected for biochemical assays. Results demonstrate that NTPDase, ectonucleotide pyrophosphatase/phosphodiesterase, and 5'-nucleotidase activities were significantly decreased in platelets of HFD group, while that adenosine deaminase (ADA) activity was significantly increased in this group in comparison to the other groups (P < 0.05). When rats that received HFD were treated with α-Toc, the activities of these enzymes were similar to the control, but ADA activity was significantly increased in relation to the control and α-Toc group (P < 0.05). HFD group showed an increased in platelet aggregation in comparison to the other groups, and treatment with α-Toc significantly reduced platelet aggregation in this group. These findings demonstrated that HFD alters platelet aggregation and purinergic signaling in the platelets and that treatment with α-Toc was capable of modulating the adenine nucleotide hydrolysis in this experimental condition

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