Methylglyoxal can mediate behavioral and neurochemical alterations in rat brain.

Diabetes is associated with loss of cognitive function and increased risk for Alzheimer's disease (AD). Advanced glycation end products (AGEs) are elevated in diabetes and AD and have been suggested to act as mediators of the cognitive decline observed in these pathologies. Methylglyoxal (MG) is an extremely reactive carbonyl compound that propagates glycation reactions and is, therefore, able to generate AGEs. Herein, we evaluated persistent behavioral and biochemical parameters to explore the hypothesis that elevated exogenous MG concentrations, induced by intracerebroventricular (ICV) infusion, lead to cognitive decline in Wistar rats. A high and sustained administration of MG (3µmol/µL; subdivided into 6days) was found to decrease the recognition index of rats, as evaluated by the object-recognition test. However, MG was unable to impair learning-memory processes, as shown by the habituation in the open field (OF) and Y-maze tasks. Moreover, a single high dose of MG induced persistent alterations in anxiety-related behavior, diminishing the anxiety-like parameters evaluated in the OF test. Importantly, MG did not alter locomotion behavior in the different tasks performed. Our biochemical findings support the hypothesis that MG induces persistent alterations in the hippocampus, but not in the cortex, related to glyoxalase 1 activity, AGEs content and glutamate uptake. Glial fibrillary acidic protein and S100B content, as well as S100B secretion (astroglial-related parameters of brain injury), were not altered by ICV MG administration. Taken together, our data suggest that MG interferes directly in brain function and that the time and the levels of exogenous MG determine the different features that can be seen in diabetic patients.

Intracerebroventricular administration of okadaic acid induces hippocampal glucose uptake dysfunction and tau phosphorylation.

Intraneuronal aggregates of neurofibrillary tangles (NFTs), together with beta-amyloid plaques and astrogliosis, are histological markers of Alzheimer's disease (AD). The underlying mechanism of sporadic AD remains poorly understood, but abnormal hyperphosphorylation of tau protein is suggested to have a role in NFTs genesis, which leads to neuronal dysfunction and death. Okadaic acid (OKA), a strong inhibitor of protein phosphatase 2A, has been used to induce dementia similar to AD in rats. We herein investigated the effect of intracerebroventricular (ICV) infusion of OKA (100 and 200ng) on hippocampal tau phosphorylation at Ser396, which is considered an important fibrillogenic tau protein site, and on glucose uptake, which is reduced early in AD. ICV infusion of OKA (at 200ng) induced a spatial cognitive deficit, hippocampal astrogliosis (based on GFAP increment) and increase in tau phosphorylation at site 396 in this model. Moreover, we observed a decreased glucose uptake in the hippocampal slices of OKA-treated rats. In vitro exposure of hippocampal slices to OKA altered tau phosphorylation at site 396, without any associated change in glucose uptake activity. Taken together, these findings further our understanding of OKA neurotoxicity, in vivo and vitro, particularly with regard to the role of tau phosphorylation, and reinforce the importance of the OKA dementia model for studying the neurochemical alterations that may occur in AD, such as NFTs and glucose hypometabolism.

Methylglyoxal and carboxyethyllysine reduce glutamate uptake and S100B secretion in the hippocampus independently of RAGE activation.

Diabetes is a metabolic disease characterized by high fasting-glucose levels. Diabetic complications have been associated with hyperglycemia and high levels of reactive compounds, such as methylglyoxal (MG) and advanced glycation endproducts (AGEs) formation derived from glucose. Diabetic patients have a higher risk of developing neurodegenerative diseases, such as Alzheimer's disease or Parkinson's disease. Herein, we examined the effect of high glucose, MG and carboxyethyllysine (CEL), a MG-derived AGE of lysine, on oxidative, metabolic and astrocyte-specific parameters in acute hippocampal slices, and investigated some of the mechanisms that could mediate these effects. Glucose, MG and CEL did not alter reactive oxygen species (ROS) formation, glucose uptake or glutamine synthetase activity. However, glutamate uptake and S100B secretion were decreased after MG and CEL exposure. RAGE activation and glycation reactions, examined by aminoguanidine and L-lysine co-incubation, did not mediate these changes. Acute MG and CEL exposure, but not glucose, were able to induce similar effects on hippocampal slices, suggesting that conditions of high glucose concentrations are primarily toxic by elevating the rates of these glycation compounds, such as MG, and by generation of protein cross-links. Alterations in the secretion of S100B and the glutamatergic activity mediated by MG and AGEs can contribute to the brain dysfunction observed in diabetic patients.

Novel sulfonyl(thio)urea derivatives act efficiently both as insulin secretagogues and as insulinomimetic compounds.

Glibenclamide is widely used in the management of non-insulin dependent diabetes mellitus, but numerous risks limit its use in therapy. In the search for novel structures that are safer and more efficient than glibenclamide, we obtained new chemical analogs based on bioisosterism, through the treatment of benzenesulfonamide derivatives with isothiocyanates and isocyanates, affording (thio)ureas with good yield. We also verified the hypoglycemic activity, through an in vivo approach. Most of these synthesized compounds improved glucose tolerance, and the mechanism of action of the best compound (7) suggests that its effect is mediated by insulin secretion, while its hypoglycemic action is triggered by glucose uptake involving GLUT4 expression and translocation through PI-3K and PKA activity and active de novo protein synthesis in skeletal muscle. Taking all these factors together, sulfonylthiourea 7 acts as an insulin secretagogue and insulinomimetic agent on glucose homeostasis, and does not exhibit toxicity in acute treatment.

Betulinic acid and 1,25(OH)2 vitamin D3 share intracellular signal transduction in glucose homeostasis in soleus muscle.

The effect of betulinic acid on glycemia and its mechanism of action compared with 1,25(OH)2 vitamin D3 in rat muscle were investigated. Betulinic acid improved glycemia, induced insulin secretion and increased the glycogen content and glucose uptake in muscle tissue. Additionally, the integrity of both PI3K and the cytoskeleton is necessary for the stimulatory action of betulinic acid in glucose uptake. The genomic effect was apparent, since cycloheximide and PD98059 nullified the stimulatory effect of betulinic acid on glucose uptake. Therefore, although this compound did not modify the DNA transcription, the protein translation was significantly improved. Also, betulinic acid increased the GLUT4 immunocontent and its translocation was corroborated by GLUT4 localization at the plasma membrane (after 180 min). On the other hand, the effect of 1,25(OH)2 vitamin D3 on glucose uptake is not mediated by PI3K and microtubule activity. In contrast, the nuclear activity of 1,25(OH)2 vitamin D3 is necessary to trigger glucose uptake. In addition, the increased DNA transcription and GLUT4 immunocontent provide evidence of a mechanism by which 1,25(OH)2 vitamin D3 contributes to glycemia. In conclusion, betulinic acid acts as an insulin secretagogue and insulinomimetic agent via PI3K, MAPK and mRNA translation and partially shares the genomic pathway with 1,25(OH)2 vitamin D3 to upregulate the GLUT4. In summary, betulinic acid regulates glycemia through classical insulin signaling by stimulating GLUT4 synthesis and translocation. In addition, it does not cause hypercalcemia, which is highly significant from the drug discovery perspective.

Brain changes in BDNF and S100B induced by ketogenic diets in Wistar rats.

AIMS: We investigated the effects of ketogenic diet (KD) on levels of tumor necrosis factor alpha (TNF-α, a classical pro-inflammatory cytokine), BDNF (brain-derived neurotrophic factor, commonly associated with synaptic plasticity), and S100B, an astrocyte neurotrophic cytokine involved in metabolism regulation. MAIN METHODS: Young Wistar rats were fed during 8weeks with control diet or two KD, containing different proportions of omega 6 and omega 3 polyunsaturated fatty acids. Contents of TNF-α, BDNF and S100B were measured by ELISA in two brain regions (hippocampus and striatum) as well as blood serum and cerebrospinal fluid. KEY FINDINGS: Our data suggest that KD was able to reduce the levels of BDNF in the striatum (but not in hippocampus) and S100B in the cerebrospinal fluid of rats. These alterations were not affected by the proportion of polyunsaturated fatty acids offered. No changes in S100B content were observed in serum or analyzed brain regions. Basal TNF-α content was not affected by KD. SIGNIFICANCE: These findings reinforce the importance of this diet as an inductor of alterations in the brain, and such changes might contribute to the understanding of the effects (and side effects) of KD in brain disorders.

Treadmill exercise induces hippocampal astroglial alterations in rats.

Physical exercise effects on brain health and cognitive performance have been described. Synaptic remodeling in hippocampus induced by physical exercise has been described in animal models, but the underlying mechanisms remain poorly understood. Changes in astrocytes, the glial cells involved in synaptic remodeling, need more characterization. We investigated the effect of moderate treadmill exercise (20 min/day) for 4 weeks on some parameters of astrocytic activity in rat hippocampal slices, namely, glial fibrillary acidic protein (GFAP), glutamate uptake and glutamine synthetase (GS) activities, glutathione content, and S100B protein content and secretion, as well as brain-derived neurotrophic factor (BDNF) levels and glucose uptake activity in this tissue. Results show that moderate treadmill exercise was able to induce a decrease in GFAP content (evaluated by ELISA and immunohistochemistry) and an increase in GS activity. These changes could be mediated by corticosterone, whose levels were elevated in serum. BDNF, another putative mediator, was not altered in hippocampal tissue. Moreover, treadmill exercise caused a decrease in NO content. Our data indicate specific changes in astrocyte markers induced by physical exercise, the importance of studying astrocytes for understanding brain plasticity, as well as reinforce the relevance of physical exercise as a neuroprotective strategy.

Green tea (-)epigallocatechin-3-gallate reverses oxidative stress and reduces acetylcholinesterase activity in a streptozotocin-induced model of dementia.

Alzheimer's disease (AD) is the most prevalent form of dementia. Intracerebroventricular (ICV) infusion of streptozotocin (STZ) provides a relevant animal model of chronic brain dysfunction that is characterized by long-term and progressive deficits in learning, memory, and cognitive behavior, along with a permanent and ongoing cerebral energy deficit. Numerous studies on green tea epigallocatechin gallate (EGCG) demonstrate its beneficial effects on cognition and memory. As such, this study evaluated, for the first time, the effects of sub-chronic EGCG treatment in rats that were submitted to ICV infusion of STZ (3mg/kg). Male Wistar rats were divided into sham, STZ, sham+EGCG and STZ+EGCG groups. EGCG was administered at a dose of 10mg/kg/day for 4 weeks per gavage. Learning and memory was evaluated using Morris' Water Maze. Oxidative stress markers and involvement of the nitric oxide (NO) system, acetylcholinesterase activity (AChE) and glucose uptake were evaluated as well as glial parameters including S100B content and secretion and GFAP content. Our results show that EGCG was not able to modify glucose uptake and glutathione content, although cognitive deficit, S100B content and secretion, AChE activity, glutathione peroxidase activity, NO metabolites, and reactive oxygen species content were completely reversed by EGCG administration, confirming the neuroprotective potential of this compound. These findings contribute to the understanding of diseases accompanied by cognitive deficits and the STZ-model of dementia.

Disrupted cytoskeletal homeostasis, astrogliosis and apoptotic cell death in the cerebellum of preweaning rats injected with diphenyl ditelluride.

In the present report 15 day-old rats were injected with 0.3µmol of diphenyl ditelluride (PhTe)(2)/kg body weight and parameters of neurodegeneration were analyzed in slices from cerebellum 3 and 6 days afterwards. The earlier responses, at day 3 after injection, included hyperphosphorylation of intermediate filament (IF) proteins from astrocyte (glial fibrillary acidic protein - GFAP - and vimentin) and neuron (low-, medium- and high molecular weight neurofilament subunits: NF-L, NF-M and NF-H); increased mitogen-activated protein kinase (MAPK) (Erk and p38MAPK) and cAMP-dependent protein kinase (PKA) activities. Also, reactive astrogliosis takes part of the early responses to the insult with (PhTe)(2), evidenced by upregulated GFAP in Western blot, PCR and immunofluorescence analysis. Six days after (PhTe)(2) injection we found persistent astrogliosis, increased propidium iodide (PI) positive cells in NeuN positive population evidenced by flow cytometry and reduced immunofluorescence for NeuN, suggesting that the in vivo exposure to (PhTe)(2) progressed to neuronal death. Moreover, activated caspase 3 suggested apoptotic neuronal death. Neurodegeneration was related with decreased [(3)H]glutamate uptake and decreased Akt immunoreactivity, however phospho-GSK-3-ß (Ser9) was not altered in (PhTe)(2) injected rat. Therefore, the present results show that the earlier cerebellar responses to (PhTe)(2) include disruption of cytoskeletal homeostasis that could be related with MAPK and PKA activation and reactive astrogliosis. Akt inhibition observed at this time could also play a role in the neuronal death evidenced afterwards. The later events of the neurodegenerative process are characterized by persistent astrogliosis and activation of apoptotic neuronal death through caspase 3 mediated mechanisms, which could be related with glutamate excitotoxicity. The progression of these responses are therefore likely to be critical for the outcome of the neurodegeneration provoked by (PhTe)(2) in rat cerebellum.

Effects of chronic caloric restriction on kidney and heart redox status and antioxidant enzyme activities in Wistar rats.

Caloric restriction (CR) has been associated with health benefits and these effects have been attributed, in part, to modulation of oxidative status by CR; however, data are still controversial. Here, we investigate the effects of seventeen weeks of chronic CR on parameters of oxidative damage/ modification of proteins and on antioxidant enzyme activities in cardiac and kidney tissues. Our results demonstrate that CR induced an increase in protein carbonylation in the heart without changing the content of sulfhydryl groups or the activities of superoxide dismutase and catalase (CAT). Moreover, CR caused an increase in CAT activity in kidney, without changing other parameters. Protein carbonylation has been associated with oxidative damage and functional impairment; however, we cannot exclude the possibility that, under our conditions, this alteration indicates a different functional meaning in the heart tissue. In addition, we reinforce the idea that CR can increase CAT activity in the kidney.

In vivo treatment with diphenyl ditelluride induces neurodegeneration in striatum of young rats: implications of MAPK and Akt pathways.

In the present report 15day-old Wistar rats were injected with 0.3µmol of diphenyl ditelluride (PhTe)(2)/kg body weight and parameters of neurodegeneration were analyzed in slices from striatum 6days afterwards. We found hyperphosphorylation of intermediate filament (IF) proteins from astrocyte (glial fibrillary acidic protein-GFAP and vimentin) and from neuron (low-, medium- and high molecular weight neurofilament subunits: NF-L, NF-M and NF-H, respectively) and increased MAPK (Erk, JNK and p38MAPK) as well as PKA activities. The treatment induced reactive astrogliosis in the striatum, evidenced by increased GFAP and vimentin immunocontent as well as their mRNA overexpression. Also, (PhTe)(2) significantly increased the propidium iodide (PI) positive cells in NeuN positive population without altering PI incorporation into GFAP positive cells, indicating that in vivo exposure to (PhTe)(2) provoked neuronal damage. Immunohistochemistry showed a dramatic increase of GFAP staining characteristic of reactive astrogliosis. Moreover, increased caspase 3 in (PhTe)(2) treated striatal slices suggested apoptotic cell death. (PhTe)(2) exposure decreased Akt immunoreactivity, however phospho-GSK-3-ß (Ser9) was unaltered, suggesting that this kinase is not directly implicated in the neurotoxicity of this compound. Therefore, the present results shed light into the mechanisms of (PhTe)(2)-induced neurodegeneration in rat striatum, evidencing a critical role for the MAPK and Akt signaling pathways and disruption of cytoskeletal homeostasis, which could be related with apoptotic neuronal death and astrogliosis.

Does methylmercury-induced hypercholesterolemia play a causal role in its neurotoxicity and cardiovascular disease?

Methylmercury (MeHg) is an environmental pollutant that biomagnifies throughout the aquatic food chain, thus representing a toxicological concern for humans subsiding on fish for their dietary intake. Although the developing brain is considered the critical target organ of MeHg toxicity, recent evidence indicates that the cardiovascular system may be the most sensitive in adults. However, data on the mechanisms mediating MeHg-induced cardiovascular toxicity are scarce. Based on the close relationship between cardiovascular disease and dyslipidemia, this study was designed to investigate the effects of long-term MeHg exposure on plasma lipid levels in mice, as well as their underlying mechanisms and potential relationships to MeHg-induced neurotoxicity. Our major finding was that long-term MeHg exposure induced dyslipidemia in rodents. Specifically, Swiss and C57BL/6 mice treated for 21 days with a drinking solution of MeHg (40 mg/l, ad libitum) diluted in tap water showed increased total and non-HDL plasma cholesterol levels. MeHg-induced hypercholesterolemia was also observed in low-density lipoprotein receptor knockout (LDLr⁻/⁻) mice, indicating that this effect was not related to decreased LDLr-mediated cholesterol transport from blood to other tissues. Although the hepatic synthesis of cholesterol was unchanged, significant signs of nephrotoxicity (glomerular shrinkage, tubular vacuolization, and changed urea levels) were observed in MeHg-exposed mice, indicating that the involvement of nephropathy in MeHg-induced lipid dyshomeostasis may not be ruled out. Notably, Probucol (a lipid-lowering drug) prevented the development of hypercholesterolemia when coadministered with MeHg. Finally, hypercholesterolemic LDLr⁻/⁻ mice were more susceptible to MeHg-induced cerebellar glial activation, suggesting that hypercholesterolemia in itself may pose a risk factor in MeHg-induced neurotoxicity. Overall, based on the strong and graded positive association between total as well as LDL cholesterol and risk of cardiovascular diseases, our data support the concept of MeHg-induced cardiovascular toxicity.

Exercise improves motor deficits and alters striatal GFAP expression in a 6-OHDA-induced rat model of Parkinson's disease.

Astrocytic changes have been demonstrated in several neurodegenerative diseases, showing that these cells play an important role in functional recovery/maintenance against brain damage. Physical exercise is known to contribute to this process; however, the cellular mechanisms involved are not fully understood. This study investigated the effects of physical exercise on motor deficits and the expression of glial fibrillary acidic protein (GFAP) in a model of Parkinson's disease (PD). Rats were divided into four groups: sham sedentary (SS) and sham trained (ST); lesioned sedentary (LS) and lesioned trained (LT). 6-OHDA was infused unilaterally into the medial forebrain bundle. Behavioral tasks were applied to evaluate motor abilities. Tyrosine hydroxylase (TH-in substantia nigra) and GFAP (in striatum) immunoreactivities (ir) were semi-quantified using optical density. The animals submitted to treadmill training completed fewer pharmacological-induced rotations when compared with sedentary animals and they also showed ameliorated motor impairments. Interestingly, although no change in TH-ir, the exercise led to restored striatal GFAP expression in the LT group while there was no effect in the ST group. This study is the first study to show data indicating the recovery of GFAP expression post-exercise in this model and further research is necessary to determine the precise action mechanisms of exercise on astrocytes in the PD.

Treadmill training restores spatial cognitive deficits and neurochemical alterations in the hippocampus of rats submitted to an intracerebroventricular administration of streptozotocin.

The intracerebroventricular infusion of streptozotocin (icv-STZ) has been largely used in research to mimic the main characteristics of Alzheimer's disease (AD), including cognitive decline, impairment of cholinergic transmission, oxidative stress and astrogliosis. Moderate physical exercise has a number of beneficial effects on the central nervous system, as demonstrated both in animals and in human studies. This study aimed to evaluate the effect of 5-week treadmill training, in the icv-SZT model of sporadic AD, on cognitive function, oxidative stress (particularly mediated by NO) and on the astrocyte marker proteins, glial fibrillary acidic protein (GFAP) and S100B. Results confirm the spatial cognitive deficit and oxidative stress in this model, as well as astroglial alterations, particularly a decrease in CSF S100B. Physical exercise prevented these alterations, as well as increasing the hippocampal content of glutathione and GFAP per se in the CA1 region. These findings reinforce the potential neuroprotective role of moderate physical exercise. Astroglial changes observed in this dementia model contribute to understanding AD and other diseases that are accompanied by cognitive deficit.

Different effects of anoxia and hind-limb immobilization on sensorimotor development and cell numbers in the somatosensory cortex in rats.

Cerebral palsy (CP) is a group of movement and posture disorders attributed to insults in the developing brain. In rats, CP-like motor deficits can be induced by early hind-limb sensorimotor restriction (SR; from postnatal days P2 to P28), associated or otherwise with perinatal anoxia (PA; on P0 and P1). In this study, we address the question of whether PA, early SR or a combination of both produces alterations to sensorimotor development. Developmental milestones (surface righting, cliff aversion, stability on an inclined surface, proprioceptive placing, auditory startle, eye opening) were assessed daily from P3 to P14. Motor skills (horizontal ladder and beam walking) were evaluated weekly (from P31 to P52). In addition, on P52, the thickness of the somatosensory (S1) and cerebellar cortices, and corpus callosum were measured, and the neuronal and glial cell numbers in S1 were counted. SR (with or without PA) significantly delayed the stability on an inclined surface and hastened the appearance of the placing reflex and impaired motor skills. No significant differences were found in the thickness measurements between the groups. Quantitative histology of S1 showed that PA, either alone or associated with SR, increased the number of glial cells, while SR alone reduced neuronal cell numbers. Finally, the combination of PA and SR increased the size of neuronal somata. We conclude that SR impairs the achievement of developmental milestones and motor skills. Moreover, both SR and PA induce histological alterations in the S1 cortex, which may contribute to sensorimotor deficits.

Beneficial effects of treadmill training in a cerebral palsy-like rodent model: walking pattern and soleus quantitative histology.

The aim of the present study was to investigate whether treadmill locomotor training could have beneficial effects on deficits consequent to perinatal anoxia, sensorimotor restriction or a combination of both. Fifty-six newborn male Wistar rats were divided into four groups: control, anoxic, sensorimotor-restricted and anoxic-sensorimotor-restricted. Rats were exposed to anoxia in the first two postnatal days (P0 and P1) and/or hind-limb sensorimotor restriction from P2 to P28 for 16 h/day. Control and experimental rats underwent treadmill training for three weeks (from P31 to P52). Body weight and walking patterns (stride length and foot angle) were measured weekly during treadmill locomotor training. Soleus muscle cross-sectional mean area and fiber density were measured using planar morphometry. Anoxia per se did not cause gait or muscle deficits. Body weight, stride length and soleus fiber cross-sectional mean area, however, were increased in trained anoxic rats. Sensorimotor-restricted animals, either with or without perinatal anoxia, showed deficits in body weight gain, decreased stride length, wider foot angle and soleus fiber atrophy. In the sensorimotor-restricted group, treadmill training improved body weight gain and stride length, and decreased the percentage of the atrophic fibers. However, in the anoxic-sensorimotor-restricted group, training improved stride length only. Three weeks of treadmill training were able to improve stride length in restricted and anoxic-restricted animals, although body weight deficit and the degree of degradation in muscle histology were reduced only in the restricted group.

Avaliação da força muscular inspiratória e expiratória em idosas praticantes de atividade física e sedentárias / Evaluation of the inspiratory and expiratory muscular force in active and sedentary elderly women

O presente estudo teve como objetivo verificar a influência da prática de atividade física no incremento da força muscular inspiratória e expiratória em mulheres idosas. Para tanto foram selecionadas 136 idosas nas faixas etárias de 65 a 80 anos. Nenhuma era fumante e não apresentava doenças neuromusculares ou pulmonares. Foram comparados dois grupos de idosas, sendo que um grupo era praticante de atividade física (caminhadas livres 2 vezes por semana) e o outro de sedentárias (controle). Na avaliação foi utilizado um manovacuômetro aneróide para investigar as pressões inspiratórias e expiratórias. Os resultados demonstraram que o grupo de praticantes de atividade física apresentou aumento significativo da Pressão Inspiratória Máxima nas faixas etárias compreendidas entre 65-69 anos (p=0,0001), 70-74 anos (p=0,0046) e 75-80 anos (p=0,0240) e, da Pressão Expiratória Máxima nas faixas etárias entre 70-74 anos (p=0,0114) e 75-80 anos (p=0,0101). Além disto estes resultados foram comparados as Tabelas de Neder et al. (1999) e Black & Hyatt (1969) em que se observou estarem abaixo dos índices indicativos de normalidade. Conclui-se que a atividade física não específica para músculos respiratórios resultou em aumento da força muscular respiratória na maioria das mulheres idosas participantes do estudo, sugerindose ainda que para uma melhor performance respiratória poderiam ser associados treinamentos específicos para a musculatura respiratória.

The present study aimed to verify the influence of physical activity in the increment of the inspiratory and expiratory muscular force in elderly women. In order to do that, 136 women were selected between 65 to 80 years old. No one of them was a smoker and no presented neuromuscular or lung diseases. Two groups of elderly women were compared, one group was practicing physical activity (free walks twice a week) and the other group was sedentary (control). In the evaluation a aneroid manovacuometro was used in order to investigate the inspiratory and expiratory pressures. The results demonstrated that the group which has done physical activity presented significant increase of the Inspiratory Pressure Maximum in age group between 65-69 years old (p=0,0001), 70-74 years old (p=0,0046) and 75-80 years old (p=0,0240) and, increase of the Expiratory Pressure Maximum in age group between 70-74 years old (p=0,0114) and 75-80 years old (p=0,0101). Besides, these results were compared to the Tables of Neder (1999) and Black & Hyatt (1969) which breathing pressures were under the indicative indexes of normality. One concluded that the physical activity which is not specific for breathing muscles can contribute to the increment of the inspiratory and expiratory muscular force in elderly women. Moreover, one suggests specific training to the respiratory musculature in order to have a better respiratory performance.