Efeitos do Exercício Aeróbico Tardio na Remodelação Cardíaca de Ratos com Infarto do Miocárdio Pequeno / Effects of Late Aerobic Exercise on Cardiac Remodeling of Rats with Small-Sized Myocardial Infarction

Resumo Fundamento: O exercício físico tem sido considerado uma importante terapia não farmacológica para a prevenção e tratamento das doenças cardiovasculares. No entanto, seus efeitos na remodelação cardíaca leve não são claros. Objetivo: Avaliar a influência do exercício aeróbico sobre a capacidade funcional, estrutura cardíaca, função ventricular esquerda (VE) e expressão gênica das subunidades da NADPH oxidase em ratos com infarto do miocárdio pequeno (IM). Métodos: Três meses após a indução do IM, ratos Wistar foram divididos em três grupos: Sham; IM sedentário (IM-SED); e IM exercício aeróbico (IM-EA). Os ratos se exercitaram em uma esteira três vezes por semana durante 12 semanas. Um ecocardiograma foi realizado antes e após o treinamento. O tamanho do infarto foi avaliado por histologia e a expressão gênica por RT-PCR. O nível de significância para análise estatística foi estabelecido em 5%. Resultados: Ratos com IM menor que 30% da área total do VE foram incluídos no estudo. A capacidade funcional foi maior no IM-EA do que nos ratos Sham e IM-SED. O tamanho do infarto não diferiu entre os grupos. Ratos infartados apresentaram aumento do diâmetro diastólico e sistólico do VE, diâmetro do átrio esquerdo e massa do VE, com disfunção sistólica. A espessura relativa da parede foi menor no grupo IM-SED do que nos grupos IM-EA e Sham. A expressão gênica das subunidades NADPH oxidase NOX2, NOX4, p22phox e p47phox não diferiu entre os grupos. Conclusão: Infarto do miocárdio pequeno altera a estrutura cardíaca e a função sistólica do VE. O exercício aeróbico tardio pode melhorar a capacidade funcional e a remodelação cardíaca por meio da preservação da geometria ventricular esquerda. A expressão gênica das subunidades da NADPH oxidase não está envolvida na remodelação cardíaca, nem é modulada pelo exercício aeróbico em ratos com infarto do miocárdio pequeno.

Abstract Background: Physical exercise has been considered an important non-pharmacological therapy for the prevention and treatment of cardiovascular diseases. However, its effects on minor cardiac remodeling are not clear. Objective: To evaluate the influence of aerobic exercise on the functional capacity, cardiac structure, left ventricular (LV) function, and gene expression of NADPH oxidase subunits in rats with small-sized myocardial infarction (MI). Methods: Three months after MI induction, Wistar rats were divided into three groups: Sham; sedentary MI (MI-SED); and aerobic exercised MI (MI-AE). The rats exercised on a treadmill three times a week for 12 weeks. An echocardiogram was performed before and after training. The infarction size was evaluated by histology, and gene expression was assessed by RT-PCR. The significance level for statistical analysis was set at 5%. Results: Rats with MI lower than 30% of the LV total area were included in the study. Functional capacity was higher in MI-AE than in Sham and MI-SED rats. The infarction size did not differ between groups. Infarcted rats had increased LV diastolic and systolic diameter, left atrial diameter, and LV mass, with systolic dysfunction. Relative wall thickness was lower in MI-SED than in the MI-AE and Sham groups. Gene expression of the NADPH oxidase subunits NOX2, NOX4, p22phox, and p47phox did not differ between groups. Conclusion: Small-sized MI changes cardiac structure and LV systolic function. Late aerobic exercise is able to improve functional capacity and cardiac remodeling by preserving the left ventricular geometry. NADPH oxidase subunits gene expression is not involved in cardiac remodeling or modulated by aerobic exercise in rats with small-sized MI.

Cardioprotection Generated by Aerobic Exercise Training is Not Related to the Proliferation of Cardiomyocytes and Angiotensin-(1-7) Levels in the Hearts of Rats with Supravalvar Aortic Stenosis.

BACKGROUND/AIMS: The beneficial effect of aerobic exercise training (ET) on cardiac remodeling caused by supravalvar aortic stenosis (AS) has been demonstrated in experimental studies; however, the mechanisms responsible for improving cardiac function are not entirely understood. We evaluated whether ET-generated cardioprotection in pressure-overloaded rats is dependent on cardiomyocyte proliferation, increased angiotensin-(1-7) (Ang-1-7) levels, and its receptor in the myocardium. METHODS: Eighteen weeks after ascending AS surgery, Wistar rats were randomly assigned to four groups: sedentary control (C-Sed), exercised control (C-Ex), sedentary aortic stenosis (AS-Sed) and exercised aortic stenosis (AS-Ex) groups. The moderate treadmill exercise protocol was performed for ten weeks. The functional capacity was assessed by treadmill exercise testing. Cardiac structure and function were evaluated by echocardiogram. Cardiomyocyte proliferation was evaluated by flow cytometry. Expression of cell cycle regulatory genes as CCND2, AURKB, CDK1, and MEIS1 was verified by RT-qPCR. Cardiac and plasma angiotensin I (Ang I), angiotensin II (Ang II), and Ang-(1-7) levels were analyzed by high-performance liquid chromatography (HPLC). The angiotensin-converting enzyme (ACE) activity was assessed by the fluorometric method and protein expression of AT1 and Mas receptors by Western blot. RESULTS: The AS-Ex group showed reduced left ventricular wall relative thickness and improved ejection fraction; also, it showed decreased gene expression of myocyte cell cycle regulators, ACE, Ang I, Ang II and Ang II/Ang-(1-7) ratio levels compared to AS-Sed group. However, ET did not induce alterations in Ang-(1-7) and cardiac Mas receptor expression and myocyte proliferation. CONCLUSION: Aerobic exercise training improves systolic function regardless of myocyte proliferation and Ang-(1-7)/Mas receptor levels. However, the ET negatively modulates the vasoconstrictor/hypertrophic axis (ACE/Ang II) and decreases the expression of negative regulatory genes of the cell cycle in cardiomyocytes of rats with supravalvular aortic stenosis.

Transcriptional analysis of THP-1 cells infected with Leishmania infantum indicates no activation of the inflammasome platform.

Leishmaniasis is caused by intracellular parasites transmitted to vertebrates by sandfly bites. Clinical manifestations include cutaneous, mucosal or visceral involvement depending upon the host immune response and the parasite species. To assure their survival inside macrophages, these parasites developed a plethora of highly successful strategies to manipulate various immune system pathways. Considering that inflammasome activation is critical for the establishment of a protective immune response in many parasite infections, in this study we determined the transcriptome of THP-1 cells after infection with L. infantum, with a particular focus on the inflammasome components. To this end, the human cell line THP-1, previously differentiated into macrophages by PMA treatment, was infected with L. infantum promastigotes. Differentiated THP-1 cells were also stimulated with LPS to be used as a comparative parameter. The gene expression signature was determined 8 hours after by RNA-seq technique. Infected or uninfected THP-1 cells were stimulated with nigericin (NIG) to measure active caspase-1 and TNF-α, IL-6 and IL-1ß levels in culture supernatants after 8, 24 and 48 hours. L. infantum triggered a gene expression pattern more similar to non-infected THP-1 cells and very distinct from LPS-stimulated cells. Some of the most up-regulated genes in L. infantum-infected cells were CDC20, CSF1, RPS6KA1, CD36, DUSP2, DUSP5, DUSP7 and TNFAIP3. Some up-regulated GO terms in infected cells included cell coagulation, regulation of MAPK cascade, response to peptide hormone stimulus, negative regulation of transcription from RNA polymerase II promoter and nerve growth factor receptor signaling pathway. Infection was not able to induce the expression of genes associated with the inflammasome signaling pathway. This finding was confirmed by the absence of caspase-1 activation and IL-1ß production after 8, 24 and 48 hours of infection. Our results indicate that L. infantum was unable to activate the inflammasomes during the initial interaction with THP-1 cells.

Medicinal cannabis in Latin America: History, current state of regulation, and the role of the pharmacist in a new clinical experience with cannabidiol oil.

OBJECTIVE: Cannabis sativa was introduced in Latin America in the 16th century. Nevertheless, many years have elapsed, and scientific progress and the medicinal use of C sativa have been restricted by the national laws of the countries in the region. SUMMARY: In Argentina, the first law on medical cannabis, approved in 2017 (#17,350), establishes a regulatory framework for the medical use and scientific research of this plant and its derivatives. In 2018, the first clinical research protocol in Latin America was approved at Hospital de Pediatria Garrahan (Buenos Aires, Argentina) to evaluate the efficacy and safety of cannabidiol (CBD) oil for the treatment of pediatric patients with refractory epilepsy. In this context, the role of pharmacists in the health care system related to the study protocol and the medicinal use of CBD has evolved from dispensing to active participation in clinical follow-up and research protocols. CONCLUSION: Considering this experience, here we discuss the active role of the clinical pharmacist in the use of medicinal cannabis. Medicinal cannabis should be controlled in a legal framework based on clinical evidence, and the participation of the pharmacist in research and clinical protocols, as well as the dispensing and provision of information on the medicinal products should be emphasized in the clinical setting.

Cryptococcus neoformans and gattii promote DNA damage in human peripheral blood mononuclear cells.

Cryptococcosis, a systemic mycosis capable of disseminating to the central nervous system with frequent lethal effects, is caused by the species Cryptococus neoformans and Cryptococcus gattii. Several infectious agents such as virus, bacteria, and parasites may be associated to DNA damage and carcinogenesis in humans. Products of the oxidative metabolism, such as NO, produced as a host defense mechanism to destroy these pathogens, have been implicated in this damage process, due to excessive production related to an established chronic inflammatory response. Here, we investigated whether C. neoformans and /or C. gattii can cause DNA damage in human peripheral blood mononuclear cells (PBMCs) and whether this process is related to NO levels produced by PBMCs. We found that both species are equally able to induce genotoxicity in PBMCs. However, an association between DNA damage and high NO levels was only detected in relation to C. gattii. The results point to the possibility that patients with cryptococcosis are more susceptible to the development of other diseases.

Benznidazole affects expression of Th1, Th17 and Treg cytokines during acute experimental Trypanosoma cruzi infection

Background The present study evaluated the effect of treatment with benznidazole on mRNA expression of IFN-γ, IL-17, IL-10, TGF-β and FoxP3 in spleen and heart tissue of BALB/c mice in the acute phase of an experimental infection with Trypanosoma cruzi, strains JLP or Y. Methods The mRNA expression of cytokines and parasite load were assessed by q-PCR. Dependent groups were compared using Student's paired t-test and independent groups were compared using Student's unpaired t-test. Results Infection with the JLP or Y strains increased expression of IFN-γ in the heart and of IL-10 and IL-17 in the spleen and heart compared to uninfected animals. Treatment increased the expression of IFN-γ and decreased the expression of IL-17, IL-10, TGF- β and Foxp3 in spleen and heart tissue compared to untreated infected animals. Conclusion Benznidazole can induce Th1 profile in the initial of the acute phase. The treatment decreased the parasite load in both organs, although the number of parasites in Y-strain-infected mice remained high. The data suggest that benznidazole may modulate cytokine expression in infection and can be dependent of the strain. However, treatment was not fully effective in the infection provoked by Y strain, probably due to the characteristics of the strain itself.(AU)

Benznidazole affects expression of Th1, Th17 and Treg cytokines during acute experimental Trypanosoma cruzi infection

Abstract Background The present study evaluated the effect of treatment with benznidazole on mRNA expression of IFN-, IL-17, IL-10, TGF- and FoxP3 in spleen and heart tissue of BALB/c mice in the acute phase of an experimental infection with Trypanosoma cruzi, strains JLP or Y. Methods The mRNA expression of cytokines and parasite load were assessed by q-PCR. Dependent groups were compared using Student's paired t-test and independent groups were compared using Student's unpaired t-test. Results Infection with the JLP or Y strains increased expression of IFN- in the heart and of IL-10 and IL-17 in the spleen and heart compared to uninfected animals. Treatment increased the expression of IFN- and decreased the expression of IL-17, IL-10, TGF- and Foxp3 in spleen and heart tissue compared to untreated infected animals. Conclusion Benznidazole can induce Th1 profile in the initial of the acute phase. The treatment decreased the parasite load in both organs, although the number of parasites in Y-strain-infected mice remained high. The data suggest that benznidazole may modulate cytokine expression in infection and can be dependent of the strain. However, treatment was not fully effective in the infection provoked by Y strain, probably due to the characteristics of the strain itself.

The Initial Months of Antiretroviral Therapy and Its Influence on AGEs, HMGB1, and sRAGE Levels in Asymptomatic HIV-Infected Individuals.

The development of the typical comorbidities of aging which currently affects people living with HIV/AIDS (PLWHA) can be partially ascribed to the persistent immune activation and chronic inflammation characterizing these individuals. The aim of this study was to analyze the effect exerted by combined antiretroviral therapy (cART) administration on plasma levels of HMGB1 (high mobility group box protein-1), AGEs (advanced glycation end products), their soluble receptor sRAGE, cytokines, C-reactive protein (CRP), and some metabolic markers in asymptomatic PLWHA. Analyses were performed longitudinally in 30 PLWHA, before and about 6-12 months after cART initiation. We observed that lower levels of AGEs in post-cART group were accompanied by an increase of CRP and triglyceride levels already in the early months of therapy. Because of the current ever-earlier recommendations to start cART and its prolonged use, these and other markers should be investigated in order to monitor and postpone the appearance of non-AIDS comorbidities in PLWHA.

The involvement of TLR2 and TLR4 in cytokine and nitric oxide production in visceral leishmaniasis patients before and after treatment with anti-leishmanial drugs.

Toll-like receptors (TLRs) have significant involvement in Leishmania infection, although little is known about the relationship between these receptors, cytokines and nitric oxide (NO) in patients with visceral leishmaniasis (VL) before or after treatment with anti-leishmanial drugs. The goal of this study was to evaluate the expression of TLR2 and TLR4 in CD3+ and CD14+ cells and the production of TNF-α, IFN-γ, IL-17, IL-10, TGF-ß and NO in peripheral blood mononuclear cells (PBMCs) from VL patients pre- and post-treatment with anti-leishmanial drugs. In addition, we investigated whether these receptors were involved in the production of these cytokines and NO. In the active VL patients, increased TLR2 and TLR4 expression in lymphocytes and monocytes, increased production of TNF-α, IL-10 and TGF-ß and decreased production of IFN-γ, IL-17 and NO were observed. After treatment, TLR2 and TLR4 were still expressed in lymphocytes and monocytes, the TNF-α and IL-10 levels were lower, the production of IFN-γ, IL-17 and NO was higher, and the TGF-ß level remained high. Before treatment, the production of TNF-α and NO was associated with TLR2 and TLR4 expression, while IL-10 production was only associated with TLR2 expression. After treatment, both receptors were associated with the production of TNF-α, IFN-γ, IL-10 and NO, while the production of IL-17 was associated only with TLR4 expression. The results presented in this study suggest that both TLR2 and TLR4 participate in the modulation of cytokine and NO production in VL patients, contributing to the pathogenesis of VL prior to treatment and the protective immune response after treatment.

Analysis of Toll-like receptors, iNOS and cytokine profiles in patients with pulmonary tuberculosis during anti-tuberculosis treatment.

Toll-like receptors (TLRs) play an important role in mycobacterial infection, although little is known about the roles of these receptors, cytokines and nitric oxide during anti-tuberculosis treatment. Our objective was to evaluate the mRNA and cell surface expression of TLR2 and TLR4; inducible nitric oxide synthase (iNOS) expression; and cytokine Th1, Th2 and Th17 profiles in pulmonary tuberculosis patients at different time points of anti-tuberculosis treatment. Peripheral blood mononuclear cells (PBMCs) were obtained from PPD(+) healthy controls and from patients receiving anti-tuberculosis treatment. Gene expression quantification was performed by qPCR, cell surface expression was assessed using flow cytometry, and cytokine quantification was conducted using the CBA technique. The treated patients presented higher gene expression and higher numbers of receptors on the cell surface of lymphocytes and monocytes than did control individuals. IL-12 and IFN-γ levels increased after the start of treatment, whereas TNF-α levels were reduced. TGF-ß presented the highest levels during treatment. IL-10 and IL-17 expression and production tended to increase during treatment. iNOS gene expression was reduced throughout treatment in patients. Our results suggest that anti-tuberculosis treatment modulates the immune response, inducing an increase in the expression of TLRs and pro- and anti-inflammatory cytokines to combat bacteria and reduce the inflammatory process.

Biochemical and nutritional evaluation of patients with visceral leishmaniasis before and after treatment with leishmanicidal drugs

Introduction Visceral leishmaniasis (VL) is caused by the intracellular protozoan Leishmania donovani complex. VL may be asymptomatic or progressive and is characterized by fever, anemia, weight loss and the enlargement of the spleen and liver. The nutritional status of the patients with VL is a major determinant of the progression, severity and mortality of the disease, as it affects the clinical progression of the disease. Changes in lipoproteins and plasma proteins may have major impacts in the host during infection. Thus, our goal was evaluate the serum total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides, glucose, albumin, globulin and total protein levels, as well as the body composition, of VL patients before and after treatment. Methods Nutritional evaluation was performed using the bioelectrical impedance analysis (BIA) to assess body composition. Biochemical data on the serum total cholesterol, HDL, LDL, triglycerides, glucose, albumin, globulin and total protein were collected from the medical charts of the patients. Results BIA indicated that both pre-treatment and post-treatment patients exhibited decreased phase angles compared to the controls, which is indicative of disease. Prior to treatment, the patients exhibited lower levels of total body water compared to the controls. Regarding the biochemical evaluation, patients with active VL exhibited lower levels of total cholesterol, HDL, LDL and albumin and higher triglyceride levels compared to patients after treatment and the controls. Treatment increased the levels of albumin and lipoproteins and decreased the triglyceride levels. Conclusions Our results suggest that patients with active VL present biochemical and nutritional changes that are reversed by treatment. .