Showing papers by "Maria Rosa Chitolina Schetinger published in 2019"

Antiproliferative and apoptotic effects of caffeic acid on SK-Mel-28 human melanoma cancer cells

Abstract: Cutaneous melanoma (CM) is an extremely aggressive cancer presenting low survival and high mortality. The vast majority of patients affected by this disease does not respond or show resistance to the chemotherapeutic drugs, which makes the treatment ineffective. In this sense, the necessity for the development of new agents to assist in CM therapy is extremely important. One of the sources of great interest in this search are compounds of natural origin. Among these compounds, caffeic acid has demonstrated a broad spectrum of pharmacological activities as well as antitumor effects in some types of cancer. Therefore, the objective of this work was to investigate the possible antitumor effect of caffeic acid on the SK-Mel-28 cell line, human CM cells. Cells were cultured in flasks with culture medium containing fetal bovine serum, antibiotic, and antifungal, and maintained in ideal conditions. Cells were treated with 25 µM, 50 µM, 100 µM, 150 µM and 200 µM of caffeic acid and dacarbazine at 1 mg/mL. We verified the effect on cell viability and cell death, apoptosis, cell cycle, colony formation and gene expression of caspases. Results showed a decrease in cell viability, cell death induction by apoptosis, inhibition of colony formation, modulation of cell cycle and alterations in gene expression of caspases after caffeic acid treatment. These results suggest an antitumor effect of the compound on SK-Mel-28 cells. This study provides original information on mechanisms by which caffeic acid may play a key role in preventing tumor progression in human melanoma cells.

Neuroprotective effects of berberine on recognition memory impairment, oxidative stress, and damage to the purinergic system in rats submitted to intracerebroventricular injection of streptozotocin.

Abstract: Alzheimer’s disease (AD) is a progressive and irreversible neurodegenerative disease. The present study investigated the effects of 50 and 100 mg/kg berberine (BRB) on recognition memory, oxidative stress, and purinergic neurotransmission, in a model of sporadic dementia of the Alzheimer’s type induced by intracerebroventricular (ICV) injection of streptozotocin (STZ) in rats. Rats were submitted to ICV-STZ 3 mg/kg or saline, and 3 days later, were started on a treatment of BRB or saline for 21 days. The results demonstrated that BRB was effective in protecting against memory impairment, increased reactive oxygen species, and the subsequent increase in protein and lipid oxidation in the cerebral cortex and hippocampus, as well as δ-aminolevulinate dehydratase inhibition in the cerebral cortex. Moreover, the decrease in total thiols, and the reduced glutathione and glutathione S-transferase activity in the cerebral cortex and hippocampus of ICV-STZ rats, was prevented by BRB treatment. Besides an antioxidant effect, BRB treatment was capable of preventing decreases in ecto-nucleoside triphosphate diphosphohydrolase (NTPDase), 5′-nucleotidase (EC-5’-Nt), and adenosine deaminase (ADA) activities in synaptosomes of the cerebral cortex and hippocampus. Thus, our data suggest that BRB exerts a neuroprotective effect on recognition memory, as well as on oxidative stress and oxidative stress-related damage, such as dysfunction of the purinergic system. This suggests that BRB may act as a promising multipotent agent for the treatment of AD.

High-intensity intermittent exercise increases adenosine hydrolysis in platelets and lymphocytes and promotes platelet aggregation in futsal athletes

Abstract: Acute bouts of high-intensity intermittent exercise (HIIE) or sports are associated with changes in lymphocytes and platelet functions and we hypothesized that the purinergic system is invo...

ADA activity is decreased in lymphocytes from patients with advanced stage of lung cancer

Abstract: Cigarette smoking is directly associated with lung cancer. Non-small cell lung carcinoma (NSCLC) represents approximately 80% from all types of lung cancer. This latter is hard to diagnose and to treat due to the lack of symptoms in early stages of the disease. The aim of this study was to evaluate ADA activity and the expression of P2X7, A1, and A2A receptors and in lymphocytes. In addition, the profile of pro-inflammatory and anti-inflammatory cytokines serum levels of patients with lung cancer in advanced stage was evaluated. Patients (n = 13) previously treated for lung cancer at stage IV (UICC) with chemotherapy had their blood collected. Cancer patients showed a decrease in ADA activity and an increase in A1 receptor expression in lymphocytes when compared to the control group. Moreover, patients exhibited an increase in IL-6 and TNF-α, while IL-17 and INF-ϒ serum levels were lower in patients with lung cancer. The decreased ADA activity and the increase in A1 receptor expression may contribute to adenosine pro-tumor effects by increasing IL-6 and TNF-α and decreasing IL-17 and INF-γ serum levels. Our data show an indirect evidence that purinergic signaling may have a role in promoting a profile of cytokines levels that favors tumor progression.

Resveratrol-mediated reversal of changes in purinergic signaling and immune response induced by Toxoplasma gondii infection of neural progenitor cells.

Abstract: The effects of Toxoplasma gondii during embryonic development have not been explored despite the predilection of this parasite for neurons and glial cells. Here, we investigated the activation of the purinergic system and proinflammatory responses during congenital infection by T. gondii. Moreover, neuroprotective and neuromodulatory properties of resveratrol (RSV), a polyphenolic natural compound, were studied in infected neuronal progenitor cells (NPCs). For this study, NPCs were isolated from the telencephalon of infected mouse embryos and subjected to neurosphere culture in the presence of EGF and FGF2. ATP hydrolysis and adenosine deamination by adenosine deaminase activity were altered in conditions of T. gondii infection. P2X7 and adenosine A2A receptor expression rates were augmented in infected NPCs together with an increase of proinflammatory (INF-γ and TNF-α) and anti-inflammatory (IL-10) cytokine gene expression. Our results confirm that RSV counteracted T. gondii-promoted effects on enzymes hydrolyzing extracellular nucleotides and nucleosides and also upregulated P2X7 and A2A receptor expression and activity, modulating INF-γ, TNF-α, and IL-10 cytokine production, which plays an integral role in the immune response against T. gondii.

Aluminum affects neural phenotype determination of embryonic neural progenitor cells

Abstract: Aluminum (Al) is a neurotoxin and is associated with the etiology of neurodegenerative diseases, such as Alzheimer’s disease (AD). The Al-free ion (Al3+) is the biologically reactive and toxic form. However, the underlying mechanisms of Al toxicity in the brain remain unclear. Here, we evaluated the effects of Al3+ (in the chloride form—AlCl3) at different concentrations (0.1–100 µM) on the morphology, proliferation, apoptosis, migration and differentiation of neural progenitor cells (NPCs) isolated from embryonic telencephalons, cultured as neurospheres. Our results reveal that Al3+ at 100 µM reduced the number and diameter of neurospheres. Cell cycle analysis showed that Al3+ had a decisive function in proliferation inhibition of NPCs during neural differentiation and induced apoptosis on neurospheres. In addition, 1 µM Al3+ resulted in deleterious effects on neural phenotype determination. Flow cytometry and immunocytochemistry analysis showed that Al3+ promoted a decrease in immature neuronal marker β3-tubulin expression and an increase in co-expression of the NPC marker nestin and glial fibrillary acidic protein. Thus, our findings indicate that Al3+ caused cellular damage and reduced proliferation and migration, resulting in global inhibition of NPC differentiation and neurogenesis.

Physical exercise prevents alterations in purinergic system and oxidative status in lipopolysaccharide‐induced sepsis in rats

Abstract: Sepsis is a generalized infection that involves alterations in inflammatory parameters, oxidant status, and purinergic signaling in many tissues. Physical exercise has emerged as a tool to prevent this disease because of its anti-inflammatory and antioxidant properties. Thus, in this study, we investigated the effects of physical exercise on preventing alterations in purinergic system components, oxidative stress, and inflammatory parameters in lipopolysaccharide (LPS)-induced sepsis in rats. Male Wistar rats were divided into four groups: control, exercise (EX), LPS, and EX+LPS. The resisted physical exercise was performed for 12 weeks on a ladder with 1 m height. After 72 hours of the last exercise session, the animals received 2.5 mg/kg of LPS for induction of sepsis, and after 24 hours, lungs and blood samples were collected for analysis. The results showed that the exercise protocol used was able to prevent, in septic animals: (1) the increase in body temperature; (2) the increase of lipid peroxidation and reactive species levels in the lung, (3) the increase in adenosine triphosphate levels in serum; (4) the change in the activity of the enzymes ectonucleotidases in lymphocytes, partially; (5) the change in the density of purinergic enzymes and receptors in the lung, and (6) the increase of IL-6 and IL-1β gene expression. Our results revealed the involvement of purinergic signaling and oxidative damage in the mechanisms by which exercise prevents sepsis aggravations. Therefore, the regular practice of physical exercise is encouraged as a better way to prepare the body against sepsis complications.

Resveratrol as a Therapy to Restore Neurogliogenesis of Neural Progenitor Cells Infected by Toxoplasma gondii

Abstract: The intracellular protozoan Toxoplasma gondii may cause congenital toxoplasmosis and serious brain damage in fetus. However, the underlying mechanism of neuropathogenesis in brain toxoplasmosis remains unclear. For this study, neural progenitor cells (NPCs) were obtained from embryo telencephalons (embryonic day 13) and induced to proliferation in the presence of growth factors (GFs). For gathering insights into the biological effects of resveratrol (RSV) on neurogenesis, this study aimed to investigate effects of RSV concentrations (0.1 to 100 μM) on proliferation, migration and differentiation of NPCs infected by T. gondii. T. gondii infection increased the presence of cells in Sub G1 phase, reducing the global frequency of undifferentiated cells in S and G2/M phases of cell cycle and reduced cell viability/mithochondrial activity of infected NPCs. Moreover T. gondii stimulated neural migration and gliogenesis during neutral differentation. However, the treatment with RSV stimulated cell proliferation, restored cellular viability of infected NPCs and exerted an inhibitory effect on gliogenesis of infected NPCs favorecing neuronal maturation during toxoplasmosis infection. Thus, we have successfully to demonstrated that RSV is promising as therapeutic for congenital toxoplasmosis.

Physical exercise prevents memory impairment in an animal model of hypertension through modulation of CD39 and CD73 activities and A2A receptor expression.

Abstract: Background: Central nervous system function has been emerging as an approach to understand hypertension-mediated memory dysfunction, and chronic exercise is able to modulate the purinergic system. Method Herein, we investigated the effect of chronic swimming training on the purinergic system in cortex and hippocampus of L-NAME-induced hypertensive rats. Male Wistar rats were divided into four groups: Control, Exercise, L-NAME and Exercise L-NAME. Inhibitory avoidance test was used to assess memory status. NTPDase, CD73 and adenosine deaminase activities and expression, and P2 receptors expression were analyzed. Data were analyzed using two-way ANOVA and Kruskal-Wallis tests, considering P less than 0.05. Results Physical exercise reduced the blood pressure and prevented memory impairment induced by L-NAME model of hypertension. L-NAME treatment promoted an increase in NTPDase1, NTPDase3 and CD73 expression and activity in the cortex. A2A expression is increased in hippocampus and cortex in the hypertension group and exercise prevented this overexpression. Conclusion These changes suggest that hypertension increases adenosine generation, which acts through A2A receptors, and exercise prevents these effects. These data may indicate a possible mechanism by which exercise may prevent memory impairment induced by L-NAME.

Protection of cholinergic and antioxidant system contributes to the effect of Vitamin D3 ameliorating memory dysfunction in sporadic dementia of Alzheimer's type.

Abstract: Objective Investigate Vitamin D3 (VD3) effect on the Acetylcholinesterase (AChE), oxidative damage and behavioral tests in animals subjected to Intracerebroventicular injection of Streptozotocin (ICV-STZ) simulating a Sporadic Dementia of Alzheimer's Type (SDAT) and treated with VD3 (21 days). Methods Animals were divided into eight groups: Vehicle, VD12.5 μg/kg, VD42 μg/kg, VD125 μg/kg, STZ, STZ+VD12.5 μg/kg, STZ+VD42 μg/kg, STZ+VD125 μg/kg. Results VD3 prevented the increase in AChE in groups of VD42 µg/kg and VD125 µg/kg; in AChE of synaptossomes and TBARS levels prevented the increase in group VD125 µg/kg; in ROS levels there was not a significant difference; for the Carbonyl Content all doses prevented the increase. Total Thiols prevent the decrease in VD42 µg/kg and VD125 µg/kg, and Reduced Glutathione prevented the decrease in VD125 µg/kg, Oxidized Glutathione prevented the increase in VD125 µg/kg. In relation to behavioral tests, the VD3 prevented the increase in time to find (days 2 and 3), in the time to find the platform (day 3) and in time spent in the quadrant (day 2). However, in relation to crossings there was not difference in groups. These results indicated the therapeutic effect of the VD3 in model of STZ in rats.

1α, 25-Dihydroxyvitamin D3 alters ectonucleotidase expression and activity in human cutaneous melanoma cells.

Abstract: Purpose We hypothesized that vitamin D decreases rates of adenosine formation in human cutaneous melanoma cells through the inhibition of extracellular adenosine 5'-triphosphate breakdown, thereby affecting tumor cell viability. Therefore, the objective of this study was to explore the mechanisms of action of 1α, 25-dihydroxyvitamin D3 (1,25(OH)2 D3) on the activity and expression of ectonucleotidases in cutaneous melanoma cells. Methods A human melanoma cell line, SK-Mel-28, was treated with 1 to 50 nM of the active vitamin D metabolite (1,25(OH)2 D3) over 24 hours, followed by determination of NTPDase1/CD39 and ecto-5'-nucleotidase/CD73 activity and expression rates of the purinergic system-related NTPDASE1, NT5E and adenosine deaminase and vitamin D receptor. An 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay was used to evaluate cellular viability. Results 1,25(OH)2 D3 decreased adenosine monophosphate hydrolysis via ecto-5'-nucleotidase/CD73 and expression of CD73, but did not change NTPDase1/CD39 activity; it increased the CD39 expression. We also observed an increase of cell viability at 1 nM, but this viability decreased as the concentrations of vitamin D active metabolite increased to 50 nM. There were no differences in gene expression levels. Conclusion To the best of our knowledge, we showed for the first time a mechanism of control of adenosine production via modulation of the purinergic system in cutaneous melanoma cells treated with the active metabolite of vitamin D. This study provides original information regarding mechanisms, in which vitamin D plays a key role in preventing tumor progression in human melanoma cells.

Dietary supplementation of jute leaf (Corchorus olitorius) modulates hepatic delta‐aminolevulinic acid dehydratase (δ‐ALAD) activity and oxidative status in high‐fat fed/low streptozotocin‐induced diabetic rats

Abstract: Impaired liver function is associated with decreased hepatic delta-aminolevulinic acid dehydratase (δ-ALAD) activity in diabetes mellitus. Hence, this study described the effect of dietary jute leaf (Corchorus olitorius) on hepatic δ-ALAD activity in high-fat fed combined with low-dose streptozotocin administered diabetic rats. Animals were fed diets containing 35% fat for 14 days prior to a single administration of low-dose (35 mg/kg body weight) streptozotocin to induce diabetes. Thereafter, the animals were randomly placed in groups and fed 100 mg/g jute leaf-supplemented diets for 30 days. The result showed that jute leaf supplementation significantly (p < 0.05) reversed the decreased hepatic δ-ALAD activity, increased hepatic catalase and SOD activity accompanying the decrease in serum AST and AST activities. This finding suggests that restoration of hepatic δ-ALAD activity, modulation of hepatic function biomarkers, and increase in antioxidant status could be possible underlying events mediating the hepatoprotective effect of jute leaf in diabetic conditions. PRACTICAL APPLICATIONS: Decrease in hepatic δ-ALAD activity has been associated with diabetes-induced hepatotoxicity arising from prolonged and uncontrolled hyperglycemia. Therefore, increased δ-ALAD activity represents improved hepatic function in diabetic situations. Antidiabetic properties of jute leaf have been demonstrated but information on its effect on hepatic δ-ALAD is lacking. Thus, this study revealed that dietary supplementation of jute leaf restored hepatic δ-ALAD activities and improved liver antioxidant status in diabetic rats which is an indication of its hepatoprotective properties.

Experimentação investigativa em eletroquímica e argumentação no ensino médio

Abstract: A argumentacao tem sido uma preocupacao na pesquisa em educacao em ciencias. E considerada benefica para a compreensao conceitual e proporciona aos alunos a capacidade de pensar criticamente em um contexto cientifico. A formulacao de argumentos e significativa no desenvolvimento de atividades cientificas, mas no contexto escolar os alunos precisam ter a oportunidade de se envolver em argumentacoes. Considerando o contexto brasileiro, essa questao ainda nao esta bem elucidada. Neste artigo, e discutido como tres atividade com experimentos investigativos em eletroquimica, com diferentes niveis de abertura, podem promover a argumentacao em um grupo de 48 alunos do ensino medio no laboratorio de quimica. O discurso durante as atividades com experimentos com alto nivel de abertura mostrou-se rico em argumentos, enquanto que durante a atividade com experimentos com baixo nivel de abertura o discurso mostrou-se escasso em argumentacao. Os argumentos foram coletados e analisados de acordo com o modelo de argumentacao de Toulmin (2006).

Diphenyl diselenide subcutaneous supplementation of dairy sheep: effects on oxidant and antioxidant status, inflammatory response and milk composition

Abstract: Diphenyl diselenide ((PhSe)2) is a organoselenium compound with potent antioxidant properties. Therefore, the aim of the present study was to evaluate whether subcutaneous supplementation of (PhSe)2 in dairy sheep has positive effects on milk composition, as well as on the prevention of oxidative stress and exacerbated inflammatory response. For this, 16 primiparous recently calved sheep were divided into the following two groups, with eight animals in each: Group A, the control group; and Group B, the group subcutaneously supplemented with five doses of (PhSe)2 of 3.0 µmol/kg each every 7 days. Blood samples from supplemented animals showed increased concentration of antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione-S-transferase), and reduced reactive oxygen species and lipid peroxidation, which prevented oxidative damage in the lactation period, as well as increased seric interleukin-10, an anti-inflammatory cytokine. In the sera, supplemented animals showed increased total antioxidant capacity and ferric-reducing ability of plasma compared with the control group. As a consequence, supplemented animals showed increased antioxidant variables, as well as reduced protein oxidation in milk samples. Moreover, milk from supplemented sheep showed a higher fat content, and lower total protein and lactose contents in some periods in the study, than did not-supplemented ewes. Seric concentrations of interleukin-1 were lower on Days 30 and 45 in supplemented animals, as well as the concentrations of tumour necrosis factor α in all periods, than were those in the control group, whereas the interleukin-10 concentrations were higher. Thus, dairy sheep supplementation of (PhSe)2 activated antioxidant and anti-inflammatory responses, and increased milk fat content. Moreover, this protocol increased the antioxidant and, consequently, reduced the oxidant concentration in milk, which is desirable for product quality.

Reflexão sobre o processo de uma pesquisa em sala de aula

Abstract: As pesquisas no campo educacional apresentam um conjunto de elementos fundamentais para compreender o processo de ensino e aprendizagem e fornecem indicios do que o contexto escolar vem vivenciando. Porem, nao e comum encontrarmos o processo que deu origem aos resultados apresentados. Este artigo apresenta uma reflexao sobre o processo de uma pesquisa de doutorado realizada em sala de aula, em uma escola privada do municipio de Santa Maria, RS, com alunos do 7o ano do ensino fundamental, durante o periodo de 2017 a 2018. Esta narrativa, baseada na pesquisa-acao e considerando o professor como um profissional reflexivo, procurou articular o percurso metodologico do estudo, os aspectos positivos, fatores limitantes e o contexto que permearam a pesquisa.

Interdisciplinaridade na percepção de docentes de ensino superior

Abstract: O objetivo foi conhecer a percepção de docentes acerca da interdisciplinaridade no ensino da fisioterapia. Participaram do estudo 10 docentes, que responderam a um questionário sobre “Interdisciplinaridade no ensino da fisioterapia”. O contato ocorreu em março de 2018, na reunião semanal do curso. Os dados foram interpretados por meio de análise de discurso. Os docentes percebem a interdisciplinaridade como uma integração, interação de diferentes saberes. Atualmente busca-se trabalhar a interdisciplinaridade de forma mais efetiva quando comparado ao passado. As estratégias utilizadas são o trabalho em equipe com diversos profissionais da área da saúde, estágio, as rodas de conversa, entre outros. O exercício da interdisciplinaridade pelos discentes ainda é difícil, mas não se pode pensar em outro modelo de formação onde a interdisciplinaridade não seja o ponto norteador, pois assim surgirão profissionais preparados e motivados para uma atuação diferenciada, competente e contemporânea.

Phytogenic as feed additive for suckling dairy calves’ has a beneficial effect on animal health and performance

Abstract: The aim of this study was to evaluate whether the use phytogenic as feed additive of Holstein calves could exert beneficial effects on animal health and performance. Thirty newborn calves were randomly divided into two groups (control and treated), and the treated consisted of 10 g of the phytogenic product diluted in milk once a day for 30 days. Blood and fecal samples were collected, and fecal score was performed daily in order to determine the occurrence of diarrhea. Treated calves showed higher hematocrit on days 45 and 60 of life. Serum levels of urea, total proteins, globulins and glucose were lower in the treated group on day 60 of life, while triglycerides were lower on days 15 and 60 of life. Serum glutathione S-transferase activity was higher in treated animals on day 60 of life. Fecal bacterial count was lower in treated animals on days 30 and 60 of life. The weight gain was higher in treated animals on days 60 and 210 of life. Based on these results, it is possible to conclude that the addition of phytogenic as feed additive for calves was able to minimize fecal bacterial infections and to increase body weight gain.

1α,25-dihydroxyvitamin D3 alters ectonucleotidase expression and activity in human cutaneous melanoma cells

Abstract: We hypothesized that vitamin D decreases rates of adenosine formation in human cutaneous melanoma cells through the inhibition of extracellular adenosine 5′‐triphosphate breakdown, thereby affecting tumor cell viability. Therefore, the objective of this study was to explore the mechanisms of action of 1α, 25‐dihydroxyvitamin D3 (1,25(OH)2D3) on the activity and expression of ectonucleotidases in cutaneous melanoma cells.

As representações sociais de sustentabilidade nos livros didáticos de biologia para o Ensino Médio no PNLEM 2018 Las representaciones sociales de sustentabilidad en los libros didácticos de biología para la Enseñanza Media en el PNLEM 2018 The social representations of sustainability in biology textbooks for High School in PNLEM 2018

Abstract: O trabalho resulta de uma avaliacao das representacoes sociais de sustentabilidade nos livros didaticos de biologia do Plano Nacional do Livro Didatico do Ensino Medio (PNLDEM) 2018. Foi realizada Analise Textual Discursiva em oito colecoes destinadas a disciplina de biologia no Ensino Medio. A fragmentacao dos textos em unidades de significado gerou quatro nucleos figurativos, os quais sao as representacoes ligadas as conferencias internacionais; risco e exagero; nova sustentabilidade; e manejo da natureza. A polissemia da proposta tambem se faz presente no discurso cientifico escolar dos livros didaticos, sendo as Nacoes Unidas a fonte referencial de significados para o conceito. As principais variacoes referem-se a possibilidade de uma sociedade mundial onde atraves da tecnica pode-se encontrar a resolucao dos desafios futuros, incluindo agora a pobreza. El trabajo resulta de una evaluacion de las representaciones sociales de sustentabilidad en los libros didacticos de biologia del Plan Nacional del Libro Didactico de la Ensenanza Media (PNLDEM) 2018. Se realizo Analisis textual Discursivo en ocho colecciones destinadas a la disciplina de biologia en la Ensenanza Media. La fragmentacion de los textos en unidades de significado genero cuatro nucleos figurativos, los cuales son las representaciones ligadas a las conferencias internacionales; riesgo y exageracion; nueva sostenibilidad; y manejo de la naturaleza. La polisemia de la propuesta tambien se hace presente en el discurso cientifico escolar de los libros didacticos, siendo las Naciones Unidas la fuente referencial de significados para el concepto. Las principales variaciones se refieren a la posibilidad de una sociedad mundial donde a traves de la tecnica se puede encontrar la resolucion de los desafios futuros, incluyendo ahora la pobreza. The social representations of sustainability in biology textbooks for High School in PNLEM 2018. Eight collections of books aimed at the discipline of biology in High School were analyzed through Discursive Textual Analysis. The fragmentation of texts into units of meaning has generated four figurative nuclei, which are representations linked to international conferences; risk and exaggeration; new sustainability; and nature management. The polysemy of the proposal is also present in the scientific discourse of school textbooks, with the United Nations being the reference source of meanings for the concept. The main variations refer to the possibility of a world society where through the technique one can find the solution of future challenges, now including poverty.

Adenosine deaminase behavior in experimental infection by Brucella ovis and its participation in the modulation of the inflammatory response

Abstract: The objective of this study was to evaluate the activity of adenosine deaminase (ADA) and its participation in the modulation of the inflammatory responses of mice experimentally infected with B. ovis. We used 48 animals, divided in two groups: group A (control) and group B (infected). We evaluated ADA activity and C-reactive protein (CRP) concentrations at four time points (days 7, 15, 30, and 60) post-infection (PI). There was a reduction in ADA activity in the acute phase (day 15 PI), followed by elevation when the infection became chronic (days 30 and 60 PI). Serum C-reactive protein levels were higher in infected animals than in the control group at all time points post-infection (P < 0.05). ADA regulates levels of extracellular adenosine, an anti-inflammatory molecule, suggesting that the enzyme had different behaviors depending on the stage of infection, i.e., ADA had anti-inflammatory action in the acute phase, but with the chronicity of the disease, the ADA had pro-inflammatory action. Therefore, we conclude that ADA participates in the pathogenesis of experimental ovine brucellosis.