ABSTRACT
BACKGROUND: Chagas heart disease is the most important clinical manifestation of Trypanosoma cruzi infection. Pharmacological therapies have been proposed aiming to reduce inflammatory response and cardiac damage in infected hosts. In this study, we investigated the use of doxycycline (Dox), in a sub-antimicrobial dose, in monotherapy and in combination with benznidazole (Bz) during the acute phase of infection with the VL-10 strain of T. cruzi, evaluating the therapeutic effect during the acute and chronic phases of the infection. METHODS AND RESULTS: C57BL/6 mice were treated for 20â¯days with Dox (30â¯mg/kg), Bz (100â¯mg/kg), or both drugs in combination starting 9â¯days after infection. Parasitemia was measured during the acute phase and the animals were monitored for 12â¯months, after which echocardiography analysis was performed. Blood samples were obtained from euthanized mice for CCL2, CCL5, IL-10 analysis, and cardiac fragments were collected for histopathological evaluation. Dox treatment did not ameliorate parasitological/inflammatory parameters but reduced the cardiac collagen neoformation (CN) in 35%. In contrast, Bz administration reduced parasitemia, plasma levels of CCL2 and CCL5, and cardiac infiltration during acute infection, and reduced the level of IL-10 and CN (95%) at 12â¯months. Dox was unable to improve ejection fraction, while Bz treatment ameliorated the ejection fraction. No additive effect was observed in combination therapy. CONCLUSION: Dox monotherapy is not effective in the acute or chronic phases of experimental cardiomyopathy induced by the VL-10 strain of T. cruzi. Furthermore, combination therapy with Dox does not potentiate the effects of Bz monotherapy.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Chagas Disease/drug therapy , Doxycycline/administration & dosage , Nitroimidazoles/administration & dosage , Trypanocidal Agents/administration & dosage , Trypanosoma cruzi/drug effects , Animals , Chagas Disease/diagnostic imaging , Drug Therapy, Combination , Male , Mice , Mice, Inbred C57BL , Trypanosoma cruzi/physiologyABSTRACT
BACKGROUND AND PURPOSE: Genetic generalized epilepsies (GGEs) encompass a group of syndromes of mainly genetic causes, characterized by the involvement of both hemispheres. MicroRNAs (miRNAs) are small non-coding RNAs with a critical role in the regulation of neuronal biological processes through gene expression modulation. Dysregulated miRNA expression has been shown in epilepsy. Due to their stability in biological fluids like serum, miRNAs have assumed a prominent role in biomarker research. Our aim was to evaluate circulating levels of three miRNAs in GGE patients and assess their putative diagnostic value. METHODS: MiR-146a, miR-155 and miR-132 were quantified by real-time polymerase chain reaction in the serum of 79 GGE patients (47 women, 32 men, 35.1 ± 12.4 years) and 67 healthy individuals (41 women, 26 men, 42.4 ± 10.1 years). Relative expression values were calculated using the 2-ΔΔCt method. Receiver operating characteristic curve analysis was performed to assess diagnostic value. MiRNA expression was correlated with clinicopathological features. RESULTS: Serum levels of miR-146a and miR-155 were significantly upregulated in GGE patients relative to controls (3.13 and 6.05, respectively). Combined miR-146a, miR-155 and miR-132 serum levels performed well as a diagnostic biomarker, discriminating GGE patients from controls with an area under the curve of 0.85, 80% specificity and 73% sensitivity. CONCLUSIONS: Our results indicate that miR-146a, miR-155 and miR-132 may partake in GGE epileptogenesis. A panel of three circulating miRNAs with potential value as a GGE biomarker is reported for the first time. Novel biomarkers may help to identify new treatment targets and contribute to improved patients' quality of life through earlier diagnosis and a more precise prognosis.
Subject(s)
Circulating MicroRNA/blood , Epilepsy, Generalized/diagnosis , Adult , Biomarkers/blood , Epilepsy, Generalized/blood , Female , Humans , Male , Middle Aged , Prognosis , Quality of Life , Real-Time Polymerase Chain Reaction/methods , Young AdultABSTRACT
Fungi of the genus Alternaria are ubiquitous indoor and outdoor airborne agents, and individuals are daily exposed to their spores. Although its importance in human infections and, particularly in respiratory allergies, there are no studies of how Alternaria spp. spores interact with host cells. Our aim was to study the early interaction of Alternaria infectoria spores with macrophages, the first line of immune defense. RAW 264.7 macrophages were infected with A. infectoria conidia, and the internalization and viability of conidia once inside the macrophages were quantified during the first 6 h of interaction. Live cell imaging was used to study the dynamics of this interaction. TNF-α production was quantified by relative gene expression, and the concentration of other cytokines (IL-1α, IL-1ß, IL-6, IL-4, IL-10, IL-17, GM-CSF and INF-γ) and a chemokine, MIP-1α, was quantified by ELISA. Conidia were rapidly internalized by macrophages, with approximately half internalized after 30 min of interaction. During the first 6 h of interaction, macrophages retained the ability to mitotically divide while containing internalized conidia. The classical macrophage-activated morphology was absent in macrophages infected with conidia, and TNF-α and other cytokines and chemokines failed to be produced. Thus, macrophages are able to efficiently phagocyte A. infectoria conidia, but, during the first 6 h, no effective antifungal response is triggered, therefore promoting the residence of these fungal conidia inside the macrophages.
Subject(s)
Alternaria/immunology , Macrophages/immunology , Macrophages/microbiology , Phagocytosis , Spores, Fungal/immunology , Alternariosis , Animals , Gene Expression Profiling , Immunologic Factors/biosynthesis , Mice , Microbial Viability , RAW 264.7 CellsABSTRACT
Particles are usually polydispersed and size is an important feature for lipid-based drug delivery systems in order to optimize cell-particle interactions as to pharmacologic action and toxicity. Lipid nanoparticles (LDE) with composition similar to that of low-density lipoprotein carrying paclitaxel were shown to markedly reduce atherosclerosis lesions induced in rabbits by cholesterol feeding. The aim of this study was to test whether two LDE fractions, one with small (20-60 nm) and the other with large (60-100 nm) particles, had different actions on the atherosclerotic lesions. The two LDE-paclitaxel fractions, prepared by microfluidization, were separated by density gradient ultracentrifugation and injected (4 mg/body weight, intravenously once a week) into two groups of rabbits previously fed cholesterol for 4 weeks. A group of cholesterol-fed animals injected with saline solution was used as control to assess lesion reduction with treatment. After the treatment period, the animals were euthanized for analysis. After treatment, both the small and large nanoparticle preparations of LDE-paclitaxel had equally strong anti-atherosclerosis action. Both reduced lesion extension in the aorta by roughly 50%, decreased the intima width by 75% and the macrophage presence in the intima by 50%. The two preparations also showed similar toxicity profile. In conclusion, within the 20-100 nm range, size is apparently not an important feature regarding the LDE nanoparticle system and perhaps other solid lipid-based systems.
Subject(s)
Atherosclerosis/drug therapy , Lipids/administration & dosage , Lipoproteins, LDL/drug effects , Nanoparticles/administration & dosage , Paclitaxel/administration & dosage , Tubulin Modulators/administration & dosage , Animals , Drug Therapy, Combination , Male , Particle Size , RabbitsABSTRACT
Cajazeira (Spondias mombin L.), of the family Anacardiaceae, is a species of fruit tree found in the Amazon region with fruits that have excellent prospects for commercial use. We aimed to evaluate the genetic diversity within and among natural populations of S. mombin, with natural occurrence in northern Mato Grosso State, by using inter-simple sequence repeat (ISSR) markers. Overall, 126 individuals were evaluated from three populations located Alta Floresta (AFL) 42, Marcelândia (MAR) 41, and Nova Bandeirantes (NBA) 43. The individuals were genotyped with 14 ISSR primers, which amplified 99 fragments. All markers, with the exception of DiGA3'A, presented a polymorphic information content above 0.25, and thus, are recommended for diversity analyses in S. mombin. Genetic diversity of the AFL [Nei's diversity (H) = 0.2430 and Shannon index (I) = 0.3547] and MAR (H = 0.2062 and I = 0.2993) populations was higher when compared to the NBA population, which presented the lowest genetic diversity (H = 0.2002 and I = 0.2957). Analysis of molecular variance showed that 77.38% of the total genetic variation is found within populations while 22.62% is found among populations. AFL and NBA are genetically the most similar populations and also the closest "Structure" revealed genetic diversity among the genotypes of each population. As there is genetic variability in both populations, and there are no genetically identical individuals, both populations can be a source of genotypes for germplasm banks and for future commercial fruitful plantations S. mombin.
Subject(s)
Anacardiaceae/genetics , Genetic Variation , Genetic Markers , Genetics, Population , Genotype , Microsatellite Repeats , Polymorphism, GeneticABSTRACT
Brazil is considered one of the domestication centers of cassava (Manihot esculenta), containing a large part of the biological diversity and traditional knowledge of the species. The aim of the present study was to evaluate the genetic diversity of cassava landraces grown by farmers in the north of Mato Grosso State, Brazil, using inter simple sequence repeat (ISSR) molecular markers. The study was carried out in the municipality of Alta Floresta, MT, on farms located in two rural areas. Seventeen cassava landraces were selected. The DNA was extracted and polymerase chain reaction amplifications were performed using 15 ISSR primers. Genetic similarity estimates were calculated using Jaccard's index and the generated matrix was used for clustering the genotypes by using UPGMA and Tocher's methods. The 15 ISSR primers amplified 120 fragments, revealing 61.67% polymorphism. The polymorphism information content ranged from 0.04 to 0.61, averaging 0.39. The most similar genotypes were AF5 and AF8, whereas the least similar were AF1 and AF16. The UPGMA clustering method formed five groups. Group I included twelve landraces, Group II contained two, and the other groups contained one landrace each. Tocher's method resulted in six groups: 12 landraces clustered in one group, and the other groups each contained one landrace. The ISSR markers proved efficient in revealing genetic diversity among the cassava landraces. The landraces grown by farmers in the two rural areas of Alta Floresta have a great variability and, thus, can be exploited in programs for breeding and preservation of the species.
Subject(s)
DNA, Plant/genetics , Manihot/genetics , Phylogeny , Polymorphism, Genetic , Brazil , DNA Primers/chemistry , DNA, Intergenic , Domestication , Farms , Genotype , Manihot/classification , Plant Breeding , Polymerase Chain ReactionABSTRACT
Pioglitazone is a synthetic agonist for the nuclear receptor peroxisome proliferator-activated receptor γ used to treat type 2 diabetes mellitus. Recently we reported that antidiabetic drugs regulate the nutritional support of spermatogenesis by Sertoli cells. Herein, we investigate the effects of pioglitazone on human Sertoli cells metabolism. Human Sertoli cells were cultured in the presence of pioglitazone (1, 10, 100µM). Protein levels of phosphofructokinase 1, lactate dehydrogenase, hexokinase, glucose transporters (GLUT1, GLUT2, GLUT3), monocarboxylate transporter 4 and oxidative phosphorylation complexes were determined by Western blot. Lactate dehydrogenase and alanine aminotransferase activity were assessed and metabolite production and consumption determined by proton nuclear magnetic resonance. Mitochondrial membrane potential was also determined. Glucose consumption more than doubled in human Sertoli cells stimulated with pioglitazone 100µM. Mitochondrial complex II protein levels increased 50% with exposure to pioglitazone (100µM) in human Sertoli cells, though mitochondrial membrane potential was decreased by 32%. The pharmacological concentration of pioglitazone (10µM) almost doubled lactate production and established crucial correlations among key intervenient of glycolysis. Moreover, in the same concentration, alanine aminotransferase decreased more than 80%. Our results suggest that pioglitazone (10µM) increases the efficiency of the glycolytic flux and lactate production by human Sertoli cells, which is essential to sustain and preserve the spermatogenic event. Thus, pioglitazone may improve male fertility and thus, be considered a suitable antidiabetic drug for men in reproductive age.
Subject(s)
Glycolysis/drug effects , Sertoli Cells/drug effects , Sertoli Cells/metabolism , Spermatogenesis/drug effects , Thiazolidinediones/pharmacology , Dose-Response Relationship, Drug , Glucose/metabolism , Humans , Lactic Acid/biosynthesis , Male , Membrane Potential, Mitochondrial/drug effects , Oxidative Stress/drug effects , Pioglitazone , Pyruvic Acid/metabolismABSTRACT
Ghrelin is a growth hormone-releasing peptide that has been suggested to interfere with spermatogenesis, though the underling mechanisms remain unknown. We studied the effect of ghrelin in human Sertoli cells (hSCs) metabolic phenotype. For that, hSCs were exposed to increasing concentrations of ghrelin (20, 100 and 500 pM) mimicking the levels reported in obese, normal weight, and severely undernourished individuals. The metabolite production/consumption was determined. The protein levels of key glycolysis-related transporters and enzymes were assessed. The lactate dehydrogenase (LDH) activity was measured. Mitochondrial complexes protein levels and mitochondria membrane potential were also measured. We showed that hSCs express the growth hormone secretagogue receptor. At the concentration present in the plasma of normal weight men, ghrelin caused a decrease of glucose consumption and mitochondrial membrane potential in hSCs, though LDH activity and lactate production remained unchanged, illustrating an alteration of glycolytic flux efficiency. Exposure of hSCs to levels of ghrelin found in the plasma of severely undernourished individuals decreased pyruvate consumption and mitochondrial complex III protein expression. All concentrations of ghrelin decreased alanine and acetate production by hSCs. Notably, the effects of ghrelin levels found in severely undernourished individuals were more pronounced in hSCs metabolic phenotype highlighting the importance of a proper eating behavior to maintain male reproductive potential. In conclusion, ghrelin acts as an energy status sensor for hSCs in a dose-dependent manner, showing an inverse association with the production of lactate, thus controlling the nutritional support of spermatogenesis.
Subject(s)
L-Lactate Dehydrogenase/metabolism , Mitochondria/metabolism , Reproduction , Sertoli Cells/metabolism , Cells, Cultured , Energy Metabolism , Ghrelin , Glycolysis , Humans , Male , Membrane Potential, Mitochondrial , Receptors, Ghrelin/metabolism , SpermatogenesisABSTRACT
RESUMO O objetivo do presente trabalho foi avaliar a influencia do tamanho e da temperatura na germinação das sementes, assim como, da posição de escarificação do tegumento e a profundidade de semeadura na emergência de plântulas de jutaí. As sementes foram separadas em três grupos: sementes pequenas, médias e grandes. A germinação das sementes foram realizadas nas temperaturas de 5, 10, 15, 20, 25, 30, 35, 40 e 45 °C e com fotoperíodo de 12 horas. As sementes escarificadas foram colocadas para germinar em 0, 2, 4 e 6 cm de profundidade de semeadura. As sementes médias e grandes apresentaram maiores porcentagens e índices de velocidade de germinação. A faixa de temperatura ótima de germinação está entre 25 e 35°C. A escarificação no hilo da semente ou não é adequada para quebra de dormência de sementes de jutaí. Profundidades de semeadura iguais ou superiores a 4 cm são inadequadas para a emergência de plântulas de jutaí.
ABSTRACT The objective of this study was to evaluate the influence of seed size and temperature on seed germination, as well as the scarification position of the tegument and sowing depth on the emergence of jutai seedlings. The seeds were separated into three groups: large, medium and small. The temperatures to which the seeds were subjected for germination were 5, 10, 15, 20, 25, 30, 35, 40, and 45°C under a photoperiod of 12 hours. The scarified seeds were placed to germinate at depths of 0, 2, 4, and 6 cm. Seed germination was affected by seed size (large and medium seeds). The optimum temperature range was found to be between 25 and 35°C. The scarification in the hilum or the tegument was enough to break the dormancy of the jutai seeds. Sowing depths equal to or deeper than 4 cm were found to be inadequate for the emergence of jutai seedlings.
Subject(s)
Seeds/classification , Germination , Seedlings/classification , Hymenaea/classification , TemperatureABSTRACT
Several species within the genus Theobroma have particularly high economic value, including T. cacao and T. grandiflorum. Other species in this genus, such as T. speciosum and T. subincanum, have potential value for use in the conservation of genetic diversity in breeding programs. These latter species could also be domesticated or improved to produce commercial products. Using 13 simple sequence repeat loci, the population structure and genetic diversity of T. speciosum and T. subincanum natural populations in the Juruena National Park, Mato Grosso State, Brazil, was studied. We sampled all individuals of each species (N = 25) present inside a designated research area established by the Program for Research on Biodiversity. The average number of alleles per locus was 5 for T. speciosum and 6.69 for T. subincanum, with average PIC values above 0.5 in both species. All evaluated individuals varied genetically. Seeds from the individuals analyzed will be useful for the development of germplasm banks and for establishment of breeding programs.
Subject(s)
Genetics, Population , Malvaceae/genetics , Parks, Recreational , Alleles , Brazil , Gene Frequency/genetics , Genetic Variation , Geography , Heterozygote , PhylogenyABSTRACT
Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown origin, in which both genetic and environmental factors are involved. One such environmental factor is vitamin D, a vital hormone that plays a specific function in the immune system homeostasis, acting through a nuclear receptor (VDR) expressed in all immune cells. Several polymorphisms of the gene that encodes this receptor have been described. Though inconsistently, these polymorphisms have been associated with clinical manifestations and SLE development.The aim of this study was to determine the possible association between VDR gene polymorphisms (BsmI, ApaI, TaqI e FokI) and SLE susceptibility and severity, in a cohort of lupus patients from the north of Portugal.A total of 170 patients (F = 155, M = 15; age = 45 ± 13.4 years) with SLE (diagnosed according the American College of Rheumatology criteria) with at least five years of disease evolution and followed in the Autoimmune Disease Clinical Immunology Unit of Centro Hospitalar do Porto were studied. Patients and 192 ethnicity-matched controls were genotyped for BsmI (rs1544410), ApaI (rs7975232), TaqI (rs731236) and FokI (rs2228570) polymorphisms by TaqMan allelic discrimination assay. Disease severity was assessed by SLICC damage score, number of affected organs, number of severe flares and pharmacological history.SLE patients with the CT genotype of FokI polymorphism have a higher SLICC value (p = 0.031). The same result was observed for the group of patients with the TT genotype of TaqI polymorphism (p = 0.046). No differences were observed in VDR genotype between patients and controls. Also, we observed that the other clinical features analysed were not influenced by VDR polymorphisms.Our study confirms a possible role of VDR gene polymorphisms in SLE. A positive association was found between VDR polymorphisms and SLE severity (chronic damage). The presence of CT genotype of FokI and TT genotype of TaqI seems to confer a worse prognosis and may constitute a risk factor for higher long-term cumulative damage in SLE patients.
Subject(s)
Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/genetics , Receptors, Calcitriol/classification , Receptors, Calcitriol/genetics , Adult , Alleles , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Middle Aged , Polymorphism, Genetic , Portugal , Risk Factors , Vitamin D Deficiency/etiologyABSTRACT
BACKGROUND: Psoriasis is a chronic, immune-mediated disease associated with several cardio-metabolic comorbidities, accelerated atherosclerosis and cardiovascular disease (CVD). Other causes beyond systemic inflammation and traditional cardiovascular risk factors (CVRF) may be implicated in the increased risk of CVD observed in these patients. Epicardial adipose tissue (EAT), a type of visceral adipose tissue surrounding the heart and coronary vessels has been implicated in the development of coronary artery disease, by endocrine mechanisms, but particularly by local inflammation. OBJECTIVE: To compare EAT volumes in psoriasis patients and controls using multidetector computed tomography (MDCT) and to analyse if eventual differences were independent from abdominal visceral adiposity; to determine, within psoriasis patients, its relation with subclinical atherosclerosis and other markers of cardiometabolic risk. METHODS: One hundred patients with severe psoriasis, without CVD underwent MDCT, with EAT and abdominal visceral fat (AVF) assessment and coronary artery calcification (CAC) quantification and were compared with 202 control patients. RESULTS: EAT volume was increased in psoriasis patients compared to control subjects, independently from age, sex and AVF, being, on average, 15.2 ± 4.41 mL higher (95% CI: 6.5-26.0, P = 0.001) than in controls. Moreover, psoriasis patients had a statistically significant higher risk of having subclinical atherosclerosis (OR 2.52, 95% CI: 1.23-5.16) than controls, after adjusting for traditional CVRF. Within psoriasis patients EAT volume was associated with subclinical atherosclerosis, independently of age, sex, psoriasis duration, classical CVRF and AVF. CONCLUSION: This study showed that psoriasis was associated with increased EAT volume independently of visceral abdominal fat and with subclinical atherosclerosis. Within psoriasis patients EAT volume was independently associated with CAC. EAT may be another important contributor to the higher cardiovascular risk observed in psoriasis.
Subject(s)
Adipose Tissue/pathology , Calcinosis/pathology , Coronary Vessels/pathology , Pericardium/pathology , Psoriasis/pathology , Adult , Case-Control Studies , Female , Humans , Male , Middle Aged , Tomography, X-Ray ComputedABSTRACT
Ischemic preconditioning (IPC) of one or two limbs improves performance of exercise that recruits the same limb(s). However, it is unclear whether IPC application to another limb than that in exercise is also effective and which mechanisms are involved. We investigated the effect of remote IPC (RIPC) on muscle fatigue, time to task failure, forearm hemodynamics, and deoxygenation during handgrip exercise. Thirteen men underwent RIPC in the lower limbs or a control intervention (CON), in random order, and then performed a constant load rhythmic handgrip protocol until task failure. Rates of contraction and relaxation (ΔForce/ΔTime) were used as indices of fatigue. Brachial artery blood flow and conductance, besides forearm microvascular deoxygenation, were assessed during exercise. RIPC attenuated the slowing of contraction and relaxation throughout exercise (P < 0.05 vs CON) and increased time to task failure by 11.2% (95% confidence interval: 0.7-21.7%, P <0.05 vs CON). There was no significant difference in blood flow, conductance, and deoxygenation between conditions throughout exercise (P > 0.05). In conclusion, RIPC applied to the lower limbs delayed the development of fatigue during handgrip exercise, prolonged time to task failure, but was not accompanied by changes in forearm hemodynamics and deoxygenation.
Subject(s)
Brachial Artery/diagnostic imaging , Hand Strength , Ischemic Preconditioning/methods , Muscle Fatigue , Muscle Strength/physiology , Muscle, Skeletal/physiology , Resistance Training/methods , Adult , Forearm/blood supply , Hemodynamics , Hemoglobins/metabolism , Humans , Male , Muscle Contraction , Muscle, Skeletal/blood supply , Muscle, Skeletal/metabolism , Myoglobin/metabolism , Spectrum Analysis , Ultrasonography, Doppler, Duplex , Young AdultABSTRACT
The purpose of this study was to determine the effect of respiratory muscle fatigue on intercostal and forearm muscle perfusion and oxygenation in patients with heart failure. Five clinically stable heart failure patients with respiratory muscle weakness (age, 66±12 years; left ventricle ejection fraction, 34±3%) and nine matched healthy controls underwent a respiratory muscle fatigue protocol, breathing against a fixed resistance at 60% of their maximal inspiratory pressure for as long as they could sustain the predetermined inspiratory pressure. Intercostal and forearm muscle blood volume and oxygenation were continuously monitored by near-infrared spectroscopy with transducers placed on the seventh left intercostal space and the left forearm. Data were compared by two-way ANOVA and Bonferroni correction. Respiratory fatigue occurred at 5.1±1.3 min in heart failure patients and at 9.3±1.4 min in controls (P<0.05), but perceived effort, changes in heart rate, and in systolic blood pressure were similar between groups (P>0.05). Respiratory fatigue in heart failure reduced intercostal and forearm muscle blood volume (P<0.05) along with decreased tissue oxygenation both in intercostal (heart failure, -2.6±1.6%; controls, +1.6±0.5%; P<0.05) and in forearm muscles (heart failure, -4.5±0.5%; controls, +0.5±0.8%; P<0.05). These results suggest that respiratory fatigue in patients with heart failure causes an oxygen demand/delivery mismatch in respiratory muscles, probably leading to a reflex reduction in peripheral limb muscle perfusion, featuring a respiratory metaboreflex.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Heart Failure/physiopathology , Intercostal Muscles/metabolism , Muscle Fatigue/physiology , Muscle, Skeletal/metabolism , Oxygen Consumption/physiology , Reflex/physiology , Respiratory Muscles/metabolism , Blood Flow Velocity/physiology , Blood Pressure/physiology , Blood Volume/physiology , Forearm , Heart Rate/physiology , Physical Exertion , Respiratory Muscles/physiopathologyABSTRACT
The purpose of this study was to determine the effect of respiratory muscle fatigue on intercostal and forearm muscle perfusion and oxygenation in patients with heart failure. Five clinically stable heart failure patients with respiratory muscle weakness (age, 66 ± 12 years; left ventricle ejection fraction, 34 ± 3%) and nine matched healthy controls underwent a respiratory muscle fatigue protocol, breathing against a fixed resistance at 60% of their maximal inspiratory pressure for as long as they could sustain the predetermined inspiratory pressure. Intercostal and forearm muscle blood volume and oxygenation were continuously monitored by near-infrared spectroscopy with transducers placed on the seventh left intercostal space and the left forearm. Data were compared by two-way ANOVA and Bonferroni correction. Respiratory fatigue occurred at 5.1 ± 1.3 min in heart failure patients and at 9.3 ± 1.4 min in controls (P<0.05), but perceived effort, changes in heart rate, and in systolic blood pressure were similar between groups (P>0.05). Respiratory fatigue in heart failure reduced intercostal and forearm muscle blood volume (P<0.05) along with decreased tissue oxygenation both in intercostal (heart failure, -2.6 ± 1.6%; controls, +1.6 ± 0.5%; P<0.05) and in forearm muscles (heart failure, -4.5 ± 0.5%; controls, +0.5 ± 0.8%; P<0.05). These results suggest that respiratory fatigue in patients with heart failure causes an oxygen demand/delivery mismatch in respiratory muscles, probably leading to a reflex reduction in peripheral limb muscle perfusion, featuring a respiratory metaboreflex.
Subject(s)
Heart Failure/physiopathology , Intercostal Muscles/metabolism , Muscle Fatigue/physiology , Muscle, Skeletal/metabolism , Oxygen Consumption/physiology , Reflex/physiology , Respiratory Muscles/metabolism , Aged , Blood Flow Velocity/physiology , Blood Pressure/physiology , Blood Volume/physiology , Female , Forearm , Heart Rate/physiology , Humans , Male , Middle Aged , Physical Exertion , Respiratory Muscles/physiopathologyABSTRACT
PURPOSE: Many health benefits have been attributed to tea (Camellia sinensis (L.)), and tea infusions are used as dietary agent and included in food supplements. Herein, we report the effect of a white tea (WTEA) extract in Sertoli cell (SC) metabolism. The SC is responsible for the nutritional support of the developing germ cells. METHODS: An aqueous WTEA extract was prepared and analyzed by (1)H-NMR. Rat SCs were cultured with or without the WTEA extract. mRNA and protein levels of glucose transporters (GLUT1 and GLUT3), phosphofructokinase, lactate dehydrogenase (LDH) and monocarboxylate transporter 4 were determined by qPCR and western blot. LDH activity was assessed and metabolite production/consumption determined by (1)H-NMR. RESULTS: WTEA-exposed SCs presented decreased protein and mRNA levels of GLUT1 and decreased glucose uptake. However, intracellular LDH activity was increased and SC lactate production was stimulated by the presence of the WTEA extract. Interestingly, alanine production was also found to be stimulated in WTEA extract-exposed SCs. CONCLUSION: WTEA extract altered the glycolytic profile of cultured SCs, stimulating lactate production. Since lactate is used as metabolic substrate and has an anti-apoptotic effect in the developing germ cells, the supplementation with WTEA extract may be advantageous to improve male reproductive health.
Subject(s)
Glycolysis/drug effects , Plant Extracts/pharmacology , Sertoli Cells/drug effects , Tea/chemistry , Animals , Apoptosis/drug effects , Blood Glucose/metabolism , Caffeine/analysis , Caffeine/pharmacology , Catechin/analysis , Catechin/pharmacology , Cells, Cultured , Glucose Transporter Type 1/genetics , Glucose Transporter Type 1/metabolism , L-Lactate Dehydrogenase/genetics , L-Lactate Dehydrogenase/metabolism , Lactic Acid/metabolism , Magnetic Resonance Spectroscopy , Male , Monocarboxylic Acid Transporters/genetics , Monocarboxylic Acid Transporters/metabolism , Muscle Proteins/genetics , Muscle Proteins/metabolism , Phosphofructokinase-1/genetics , Phosphofructokinase-1/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Wistar , Reproduction/drug effects , Sertoli Cells/metabolismABSTRACT
Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease with strong genetic and environmental components. Previous studies have shown increased levels of several chemokines in active SLE. C-C chemokine receptor type 5 (CCR5) is involved in the recruitment of inflammatory cells into tissues, and mechanisms modulating CCR5 expression and function may interfere in SLE development, influencing the clinical course of the disease. The aim of this study was to evaluate the possible association between the CCR5∆32 base-pair deletion polymorphism and SLE disease in a group of Portuguese patients. A total of 219 patients with SLE and 205 healthy individuals were studied. The frequency of CCR5/∆32 heterozygotes was lower in patients with SLE than in controls (8% vs. 15% OR = 0.5162; P = 0.0319), suggesting a protective association between CCR5∆32 allele and SLE. These results highlight the protective role of Th1 cells that express CCR5 in SLE pathogenesis.
Subject(s)
Base Sequence , Lupus Erythematosus, Systemic/genetics , Receptors, CCR5/genetics , Sequence Deletion , Th1 Cells/metabolism , Adult , Alleles , Case-Control Studies , Female , Gene Expression , Gene Frequency , Heterozygote , Humans , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/pathology , Male , Middle Aged , Molecular Sequence Data , Portugal , Severity of Illness Index , Th1 Cells/immunology , Th1 Cells/pathologyABSTRACT
More than 40% of the new drugs registered from 1981 to 2006 were obtained, derived or inspired from natural compounds. The influence of natural products in the anti-infective area is quite marked, being a great percentage of drugs derived or extracted from natural products. Vaginal infections are one of the most common reasons a women visits a gynecologist. Given the high popularity of natural therapies among women who suffer from chronic infections, it is urgent for women's healthcare providers to be knowledgeable about such therapies. Additionally, many phytotherapeutic products have been suggested as natural sources of antimicrobial compounds. The increased resistance to conventional antibiotics is one of the main factors justifying the search and development of new antimicrobial agents, especially those of natural origin. Currently, phytochemicals are considered by the scientific community as very attractive targets for potential drug discovery and therapy. In this review, we will focus on the most relevant reports published during the last twenty years about the antimicrobial activity of plant extracts upon microorganisms most frequently involved in genital infections, such as Candida spp., Gardnerella vaginalis, Trichomonas vaginalis and Human papillomavirus. The relationship between their composition and the antimicrobial effects will be highlighted and vaginal therapeutic delivery systems that vehicle plant extracts both commercialized and under investigation will be included.
Subject(s)
Anti-Infective Agents/therapeutic use , Biological Products/therapeutic use , Drug Discovery , Plants/chemistry , Reproductive Tract Infections/drug therapy , Anti-Infective Agents/pharmacology , Bacteria/drug effects , Biological Products/chemistry , Biological Products/pharmacology , Female , Fungi/drug effects , Humans , Viruses/drug effectsABSTRACT
In isolated hippocampal slices, decaying long-term potentiation can be stabilized and converted to late long-term potentiation lasting many hours, by prior or subsequent strong high-frequency tetanization of an independent input to a common population of neurons-a phenomenon known as 'synaptic tagging and capture'. Here we show that the same phenomenon occurs in the intact rat. Late long-term potentiation can be induced in CA1 during the inhibition of protein synthesis if an independent input is strongly tetanized beforehand. Conversely, declining early long-term potentiation induced by weak tetanization can be converted into lasting late long-term potentiation by subsequent strong tetanization of a separate input. These findings indicate that synaptic tagging and capture is not limited to in vitro preparations; the past and future activity of neurons has a critical role in determining the persistence of synaptic changes in the living animal, thus providing a bridge between cellular studies of protein synthesis-dependent synaptic potentiation and behavioural studies of memory persistence.
Subject(s)
Long-Term Potentiation/physiology , Synapses/physiology , Animals , Anisomycin/pharmacology , Benzazepines/pharmacology , CA1 Region, Hippocampal/physiology , CA3 Region, Hippocampal/physiology , Dopamine/physiology , Dopamine Antagonists/pharmacology , Dose-Response Relationship, Drug , Hippocampus/physiology , Male , Neurons/physiology , Protein Synthesis Inhibitors/pharmacology , Rats , Synaptic Potentials/physiologyABSTRACT
To determine the hemodynamic mechanisms responsible for the attenuated blood pressure response to mental stress after exercise, 26 healthy sedentary individuals (age 29 ± 8 years) underwent the Stroop color-word test before and 60 min after a bout of maximal dynamic exercise on a treadmill. A subgroup (N = 11) underwent a time-control experiment without exercise. Blood pressure was continuously and noninvasively recorded by infrared finger photoplethysmography. Stroke volume was derived from pressure signals, and cardiac output and peripheral vascular resistance were calculated. Perceived mental stress scores were comparable between mental stress tests both in the exercise (P = 0.96) and control (P = 0.24) experiments. After exercise, the blood pressure response to mental stress was attenuated (pre: 10 ± 13 vs post: 6 ± 7 mmHg; P < 0.01) along with lower values of systolic blood pressure (pre: 129 ± 3 vs post: 125 ± 3 mmHg; P < 0.05), stroke volume (pre: 89.4 ± 3.5 vs post: 76.8 ± 3.8 mL; P < 0.05), and cardiac output (pre: 7.00 ± 0.30 vs post: 6.51 ± 0.36 L/min; P < 0.05). Except for heart rate, the hemodynamic responses and the mean values during the two mental stress tests in the control experiment were similar (P > 0.05). In conclusion, a single bout of maximal dynamic exercise attenuates the blood pressure response to mental stress in healthy subjects, along with lower stroke volume and cardiac output, denoting an acute modulatory action of exercise on the central hemodynamic response to mental stress.