Insulin receptor substrates differentially exacerbate insulin-mediated left ventricular remodeling.

Pressure overload (PO) cardiac hypertrophy and heart failure are associated with generalized insulin resistance and hyperinsulinemia, which may exacerbate left ventricular (LV) remodeling. While PO activates insulin receptor tyrosine kinase activity that is transduced by insulin receptor substrate 1 (IRS1), the present study tested the hypothesis that IRS1 and IRS2 have divergent effects on PO-induced LV remodeling. We therefore subjected mice with cardiomyocyte-restricted deficiency of IRS1 (CIRS1KO) or IRS2 (CIRS2KO) to PO induced by transverse aortic constriction (TAC). In WT mice, TAC-induced LV hypertrophy was associated with hyperactivation of IRS1 and Akt1, but not IRS2 and Akt2. CIRS1KO hearts were resistant to cardiac hypertrophy and heart failure in concert with attenuated Akt1 activation. In contrast, CIRS2KO hearts following TAC developed more severe LV dysfunction than WT controls, and this was prevented by haploinsufficiency of Akt1. Failing human hearts exhibited isoform-specific IRS1 and Akt1 activation, while IRS2 and Akt2 activation were unchanged. Kinomic profiling identified IRS1 as a potential regulator of cardioprotective protein kinase G-mediated signaling. In addition, gene expression profiling revealed that IRS1 signaling may promote a proinflammatory response following PO. Together, these data identify IRS1 and Akt1 as critical signaling nodes that mediate LV remodeling in both mice and humans.

Identification of a Paracrine Signaling Mechanism Linking CD34high Progenitors to the Regulation of Visceral Fat Expansion and Remodeling.

Accumulation of visceral (VIS) is a predictor of metabolic disorders and insulin resistance. This is due in part to the limited capacity of VIS fat to buffer lipids allowing them to deposit in insulin-sensitive tissues. Mechanisms underlying selective hypertrophic growth and tissue remodeling properties of VIS fat are not well understood. We identified subsets of adipose progenitors (APs) unique to VIS fat with differential Cd34 expression and adipogenic capacity. VIS low (Cd34 low) APs are adipogenic, whereas VIS high (Cd34 high) APs are not. Furthermore, VIS high APs inhibit adipogenic differentiation of SUB and VIS low APs in vitro through the secretion of soluble inhibitory factor(s). The number of VIS high APs increased with adipose tissue expansion, and their abundance in vivo caused hypertrophic growth, fibrosis, inflammation, and metabolic dysfunction. This study unveils the presence of APs unique to VIS fat involved in the paracrine regulation of adipogenesis and tissue remodeling.

Activation of IGF-1 receptors and Akt signaling by systemic hyperinsulinemia contributes to cardiac hypertrophy but does not regulate cardiac autophagy in obese diabetic mice.

Autophagy plays an important role in the maintenance of normal heart function. However, the role of autophagy in the inulin resistant and diabetic heart is not well understood. Furthermore, the upstream signaling and the downstream targets involved in cardiac autophagy regulation during obesity and type 2 diabetes mellitus (T2DM) are not fully elucidated. The aim of this study was to measure autophagic flux and to dissect the upstream and downstream signaling involved in cardiac autophagy regulation in the hearts of obese T2DM mice. Our study demonstrated that cardiac autophagic flux is suppressed in the heart of obese diabetic (ob/ob) mice due to impaired autophagosome formation. We showed that suppression of autophagy was due to sustained activation of mTOR as we could restore cardiac autophagy by inhibiting mTOR. Moreover, the novel finding of this study is that while IGF-1 receptor-mediated Akt activation contributes to cardiac hypertrophy, it is not involved in mTOR activation and autophagy suppression in obesity and T2DM. In contrast, inhibition of ERK signaling abolished mTOR activation and restored autophagy in the heart of obese diabetic (ob/ob) mice. The study identifies mechanisms regulating cardiac autophagy in obesity and T2DM that are mediated by ERK/mTOR but are distinct from Akt. The findings are of significant importance as they demonstrate for the first time the contribution of IGF-1 receptors (IGF-1R) and Akt signaling in cardiac hypertrophy but not in cardiac autophagy regulation in obesity and T2DM.

Grape skin extract-derived polyphenols modify programming-induced renal endowment in prenatal protein-restricted male mouse offspring.

PURPOSE: Protein-restricted diet during pregnancy is related to oxidative stress and, as a consequence, damage to nephrogenesis. We investigated the effects of vinifera grape skin extract (ACH09)-derived polyphenols on preserving renal morphology of maternal protein-restricted 1-day-old offspring. METHODS: Female C57/Bl-6 mice were fed two different isocaloric diets: control diet (19.3 % protein) and low-protein diet (6 % protein) with access to water or to the extract dissolved in drinking water (19.3 % protein plus ACH09 200 mg kg(-1) day(-1) and 6 % protein plus ACH09 200 mg kg(-1) day(-1)) throughout gestation. Renal morphology-glomerular number N[glom]; renal maturity-vascular glomeruli and avascular glomeruli ratio (v-N[glom]/a-N[glom]); medullar and cortical volumes, as well as mean glomerular volume, were analyzed in male offspring. Hepatic superoxide dismutase and catalase (CAT) activities were evaluated, and renal lipid peroxidation levels were measured. RESULTS: Maternal protein restriction affected birth weight and naso-anal length in low-protein offspring compared to control and ACH09 restored both parameters. Protein restriction increased lipid peroxidation in kidney and liver and reduced CAT activity in low-protein group compared to control. Supplementation with ACH09 reduced the kidney oxidative damage and restored the antioxidant activity of CAT. ACH09 prevented glomerular loss and renal immaturity in the offspring. CONCLUSION: The treatment of low-protein-fed dams during pregnancy with ACH09 provides protection from early-life deleterious renal morphological changes. The protective effect of ACH09 may involve antioxidant action and vasodilator effect of the extract.

The influence of 5-lipoxygenase on cigarette smoke-induced emphysema in mice.

BACKGROUND: Pulmonary emphysema is characterized by the loss of lung architecture. Our hypothesis is that the inhibition of 5-lipoxygenase (5-LO) production may be an important strategy to reduce inflammation, oxidative stress, and metalloproteinases in lung tissue resulting from cigarette smoke (CS)-induced emphysema. METHODS: 5-LO knockout (129S2-Alox5(tm1Fun)/J) and wild-type (WT) mice (129S2/SvPas) were exposed to CS for 60days. Mice exposed to ambient air were used as Controls. Oxidative, inflammatory, and proteolytic markers were analyzed. RESULTS: The alveolar diameter was decreased in CS 5-LO(-/-) mice when compared with the WT CS group. The CS exposure resulted in less pronounced pulmonary inflammation in the CS 5-LO(-/-) group. The CS 5-LO(-/-) group showed leukotriene B4 values comparable to those of the Control group. The expression of MMP-9 was decreased in the CS 5-LO(-/-) group when compared with the CS WT group. The expression of superoxide dismutase, catalase, and glutathione peroxidase were decreased in the CS 5-LO(-/-) group when compared with the Control group. The protein expression of nuclear factor (erythroid-derived 2)-like 2 was reduced in the CS 5-LO(-/-) group when compared to the CS WT group. CONCLUSION: In conclusion, we show for the first time that 5-LO deficiency protects 129S2 mice against emphysema caused by CS. We suggest that the main mechanism of pathogenesis in this model involves the imbalance between proteases and antiproteases, particularly the association between MMP-9 and TIMP-1. General significance This study demonstrates the influence of 5-LO mediated oxidative stress, inflammation, and proteolytic markers in CS exposed mice.

Antioxidant action of propolis on mouse lungs exposed to short-term cigarette smoke.

Propolis is a natural product with antioxidant properties. In this study, we tested the efficacy of propolis against acute lung inflammation (ALI) caused by cigarette smoke (CS). C57BL6 male mice were exposed to CS and treated with propolis (200mg/kg orally, CS+P) or only with propolis (P). A Control group treated with propolis was sham-smoked (Control+P). We collected the lungs for histological and biochemical analyses. We observed an increase in alveolar macrophages and neutrophils in the CS group compared with the Control+P. These counts reduced in the CS+P group compared to the CS group. The treatment with propolis normalized all biochemical parameters in the CS+P group compared with the CS group, including nitrite, myeloperoxidase level, antioxidant enzyme activities (superoxide dismutase, catalase and glutathione peroxidase), reduced glutathione/oxidized glutathione ratio and malondialdehyde. Additionally, TNF-α expression reduced in the CS+P group when compared with the CS group. These data imply a potential antioxidant and anti-inflammatory role for propolis with regard to ALI caused by CS in mice.

Euterpe oleracea Mart.-derived polyphenols prevent endothelial dysfunction and vascular structural changes in renovascular hypertensive rats: role of oxidative stress.

The consumption of polyphenol-rich foods is associated with a decreased risk of mortality from cardiovascular diseases. Previously, we have demonstrated that the stone of Euterpe oleracea Mart. (açaí) from the Amazon region exerts vasodilator and antioxidant actions. This study examined the effect of açaí stone extract (ASE) on the vascular functional and structural changes and oxidative stress associated with the two-kidney, one-clip (2K-1C) renovascular hypertension. 2K-1C and sham-operated rats were treated with ASE 200 mg/kg/day (or vehicle) for 40 days. Blood pressure was measured by tail plethysmography, and the vascular reactivity was evaluated in the rat isolated mesenteric arterial bed. Mesenteric protein expression of endothelial nitric oxide synthase (eNOS), superoxide dismutase 1 and 2 (SOD1 and SOD2), metalloproteinase 2 (MMP-2), and tissue inhibitor of MMPs (TIMP)-1 was assessed by Western blot; oxidative damage and antioxidant activity by spectrophotometry; MMP-2 levels by gelatin zymography; and structural changes by histological analysis. ASE prevented 2K-1C hypertension and the reduction of acetylcholine-induced vasodilation. The increased levels of malondialdehyde and carbonyl protein were reduced by ASE. SOD, catalase, and glutathione peroxidase activities and the expressions of SOD1 and SOD2, eNOS, and TIMP-1 were decreased in 2K-1C rats and recovered by ASE. In 2K-1C rats, ASE prevented vascular remodeling and the increased expression/levels of MMP-2. These findings indicate that ASE produces antihypertensive effect and prevents the endothelial dysfunction and vascular structural changes in 2K-1C hypertension, probably through mechanisms involving antioxidant effects, NOS activation, and inhibition of MMP-2 activation.

Oxidative damage in alveolar macrophages exposed to cigarette smoke extract and participation of nitric oxide in redox balance.

Nitric oxide (NO) acts in both pathological and biological processes. We investigated the role of NO in the regulation of cigarette smoke-induced oxidative stress in rat alveolar macrophages (RAM). RAM collected from Wistar rats were cultured in 5% concentration cigarette smoke extract (CSE) for 1h. RAM exposed to CSE were then co-incubated with L-NAME (LN), L-arginine (LA), N-acetylcysteine (NAC) and both LN and NAC. RAM cultured only with medium was considered as control group. Biochemical analysis were performed to measure cellular metabolism (MTT), nitrite levels, superoxide dismutase (SOD) and glutathione peroxidase activities, reduced glutathione (GSH) and oxidized (GSSG), malondialdehyde and myeloperoxidase activity. During exposure to CSE, increased NO levels were not only associated with an increase of cell activation, but also affected MTT levels in RAM. CSE exposure resulted in significant redox imbalance in RAM. NAC administration affected SOD antioxidant profile regardless NO levels; however nitrite values were associated with GSH/GSSG ratio. In addition, lipid peroxidation appeared to be nitric-oxide dependent. Furthermore, the use of NAC significantly reduced the expression of NFkB normally observed in RAM exposed to CSE. The present results show that NO appeared to be involved in RAM activation, oxidative status maintenance and lipid peroxidation process during exposure to CSE.

Low tidal volume mechanical ventilation and oxidative stress in healthy mouse lungs.

OBJECTIVE: Mechanical ventilation (MV) itself can directly contribute to lung injury. Therefore, the aim of the present study was to investigate early biomarkers concerning oxidant/antioxidant balance, oxidative stress, and inflammation caused by short-term MV in healthy mouse lungs. METHODS: Twenty male C57BL/6 mice were randomly divided into two groups: MV, submitted to low tidal volume (V T, 6 mL/kg) MV for 30 min; and spontaneous respiration (SR), used as controls. Lung homogenate samples were tested regarding the activity of various antioxidant enzymes, lipid peroxidation, and TNF-α expression. RESULTS: In comparison with the SR group, the MV group showed a significant decrease in the activity of superoxide dismutase (≈35%; p < 0.05), together with an increase in the activity of catalase (40%; p < 0.01), glutathione peroxidase (500%; p < 0.001), and myeloperoxidase (260%; p < 0.001), as well as a reduction in the glutathione/oxidized glutathione ratio (≈50%; p < 0.05) and an increase in TNF-α expression in the MV group. Oxidative damage, assessed by lipid peroxidation, was also greater in the MV group (45%; p < 0.05). CONCLUSIONS: Our results show that short-term low V T MV can directly contribute to lung injury, generating oxidative stress and inflammation in healthy mouse lungs.

Ventilação mecânica com baixo volume corrente e estresse oxidativo em pulmões saudáveis de camundongos / Low tidal volume mechanical ventilation and oxidative stress in healthy mouse lungs

OBJETIVO: A ventilação mecânica (VM) por si própria pode contribuir diretamente para a lesão pulmonar. Assim, o objetivo do presente estudo foi investigar biomarcadores precoces relacionados ao equilíbrio oxidantes/antioxidantes, estresse oxidativo e inflamação causados por VM de curta duração em pulmões de camundongos saudáveis. MÉTODOS: Vinte camundongos C57BL/6 machos foram randomicamente divididos em dois grupos: VM, submetidos a VM com baixo volume corrente (V T, 6 mL/kg) por 30 min; e respiração espontânea (RE), utilizados como controles. Amostras de homogeneizados de pulmão foram testados quanto à atividade de enzimas antioxidantes, peroxidação lipídica e expressão de TNF-α. RESULTADOS: Comparados ao grupo RE, houve uma redução significativa na atividade de superóxido dismutase (≈35 por cento; p < 0,05) e aumento da atividade de catalase (40 por cento; p < 0,01), glutationa peroxidase (500 por cento; p < 0,001) e mieloperoxidase (260 por cento; p < 0,001), ao passo que a razão glutationa reduzida/glutationa oxidada foi menor (≈50 por cento; p < 0,05), e houve um aumento na atividade de expressão de TNF-α no grupo VM. O dano oxidativo, analisado como peroxidação lipídica, também aumentou no grupo VM (45 por cento; p < 0.05). CONCLUSÕES: Nossos resultados demonstraram que VM de curta duração com baixa V T pode contribuir diretamente para a lesão pulmonar, gerando estresse oxidativo e inflamação em pulmões de camundongos saudáveis.

OBJECTIVE: Mechanical ventilation (MV) itself can directly contribute to lung injury. Therefore, the aim of the present study was to investigate early biomarkers concerning oxidant/antioxidant balance, oxidative stress, and inflammation caused by short-term MV in healthy mouse lungs. METHODS: Twenty male C57BL/6 mice were randomly divided into two groups: MV, submitted to low tidal volume (V T, 6 mL/kg) MV for 30 min; and spontaneous respiration (SR), used as controls. Lung homogenate samples were tested regarding the activity of various antioxidant enzymes, lipid peroxidation, and TNF-α expression. RESULTS: In comparison with the SR group, the MV group showed a significant decrease in the activity of superoxide dismutase (≈35 percent; p < 0.05), together with an increase in the activity of catalase (40 percent; p < 0.01), glutathione peroxidase (500 percent; p < 0.001), and myeloperoxidase (260 percent; p < 0.001), as well as a reduction in the glutathione/oxidized glutathione ratio (≈50 percent; p < 0.05) and an increase in TNF-α expression in the MV group. Oxidative damage, assessed by lipid peroxidation, was also greater in the MV group (45 percent; p < 0.05). CONCLUSIONS: Our results show that short-term low V T MV can directly contribute to lung injury, generating oxidative stress and inflammation in healthy mouse lungs.

Effects of Euterpe oleracea Mart. (AÇAÍ) extract in acute lung inflammation induced by cigarette smoke in the mouse.

Short term inhalation of cigarette smoke (CS) induces significant lung inflammation due to an imbalance of oxidant/antioxidant mechanisms. Açai fruit (Euterpe oleracea) has significant antioxidant and anti-inflammatory actions. The present study aimed to determine whether oral administration of an açai stone extract (ASE) could reduce lung inflammation induced by CS. Thirty C57BL/6 mice were assigned to three groups (n=10 each): the Control+A group was exposed to ambient air and treated orally with ASE 300 mg/kg/day; the CS group was exposed to smoke from 6 cigarettes per day for 5 days; and the CS+A group was exposed to smoke from 6 cigarettes per day for 5 days and treated orally with ASE (300 mg/kg/day). On day 6, all mice were sacrificed. After bronchoalveolar lavage, the lungs were removed for histological and biochemical analyses. The CS group exhibited increases in alveolar macrophage (AMs) and neutrophil numbers (PMNs), myeloperoxidase (MPO), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase activities (GPx), TNF-α expression, and nitrites levels in lung tissue when compared with the control ones (p<0.001 for all parameters). The AMs, PMNs, MPO, SOD, CAT, GPx and nitrite were significantly reduced by oral administration of ASE when compared with CS group (p<0.001 for all parameters, with exception of AMs p<0.01). The present results suggested that systemic administration of an ASE extract could reduce the inflammatory and oxidant actions of CS. Thus, the results of this study in mice should stimulate future studies on ASE as a potential agent to protect against CS-induced inflammation in humans.

Grape skin extract reduced pulmonary oxidative response in mice exposed to cigarette smoke.

BACKGROUND: Oxidative stress has been implicated in the pathogenesis and progression of chronic obstructive pulmonary disease (COPD), and cigarette smoke (CS) is known to be one of the major sources of oxidants in the lungs. We postulated that acute administration of GSE (grape skin extract) would either reduce or protect the ALI (acute lung inflammation) produced by CS via NO release. MATERIAL/METHODS: We adopted a nutritional approach by investigating the inflammatory cells, metalloproteinase 9 (MMP-9) activity, and oxidative stress markers (superoxide dismutase - SOD; catalase - CAT; glutathione peroxidase (GPx) activities and malondialdehyde - MDA - levels) that play a role in the development of acute lung inflammation (ALI). Therefore, we tested an orally active antioxidant produced from grape skin manipulation (grape skin extract - GSE), in mice exposed to CS from 6 cigarettes a day for 5 days. In addition, we used a separate group treated with NG-nitro-L-arginine methyl ester (an NO inhibitor) to confirm nitric oxide (NO) involvement in GSE effects. RESULTS: We showed for the first time that administration of GSE inhibited ALI and oxidative damage induced by CS. This is associated with decreased MMP-9 activity, decreased number of inflammatory cells in the bronchoalveolar lavage fluid, and reduced levels of lipid peroxidation. Our results indicate that beneficial effects of GSE are NO-dependent. CONCLUSIONS: The study indicates that alteration of the oxidant-antioxidant balance is important in the pathogenesis of CS-induced ALI and suggests lung protective effects of GSE treatment in the mouse.

Long-term exposure to cigarette smoke impairs lung function and increases HMGB-1 expression in mice.

Cigarette smoke (CS)-induced emphysema is caused by a continuous inflammatory response in the lower respiratory tract. The development of the condition is believed to be mediated by oxidant-antioxidant imbalance. This paper describes the effects of long-term CS exposure on alveolar cell recruitment, antioxidant defense systems, activity of extracellular matrix metalloelastases, expression of metalloelastase MMP-12, and high mobility group box-1 protein (HMGB-1). Ten C57Bl/6 mice were exposed to 12 cigarettes-a-day for 60 consecutive days, while 10 control animals were exposed to ambient air. After sacrifice, bronchoalveolar lavage fluid (BALF) was removed, and lung tissue underwent biochemical and histological analyses. In CS-exposed animals influx of alveolar macrophages and neutrophils into BALF, lung static elastance, and expression of MMP-12 and HMGB-1 were significantly increased while the activity of antioxidant enzyme was significantly reduced in comparison with control group. Thus, we demonstrated for the first time that long-term CS exposure decreased antioxidant defenses concomitantly with impaired lung function, which was associated with HMGB-1 expression.

Addition of açaí (Euterpe oleracea) to cigarettes has a protective effect against emphysema in mice.

Chronic inhalation of cigarette smoke (CS) induces emphysema by the damage contributed by oxidative stress during inhalation of CS. Ingestion of açai fruits (Euterpe oleracea) in animals has both antioxidant and anti-inflammatory effects. This study compared lung damage in mice induced by chronic (60-day) inhalation of regular CS and smoke from cigarettes containing 100mg of hydroalcoholic extract of açai berry stone (CS + A). Sham smoke-exposed mice served as the control group. Mice were sacrificed on day 60, bronchoalveolar lavage was performed, and the lungs were removed for histological and biochemical analyses. Histopathological investigation showed enlargement of alveolar space in CS mice compared to CS + A and control mice. The increase in leukocytes in the CS group was higher than the increase observed in the CS + A group. Oxidative stress, as evaluated by antioxidant enzyme activities, mieloperoxidase, glutathione, and 4-hydroxynonenal, was reduced in mice exposed to CS+A versus CS. Macrophage and neutrophil elastase levels were reduced in mice exposed to CS + A versus CS. Thus, the presence of açai extract in cigarettes had a protective effect against emphysema in mice, probably by reducing oxidative and inflammatory reactions. These results raise the possibility that addition of açaí extract to normal cigarettes could reduce their harmful effects.

N-(2-mercaptopropionyl)-glycine but not allopurinol prevented cigarette smoke-induced alveolar enlargement in mouse.

We investigated the possible protective effects of the Allopurinol (A), N-(2-mercaptopropionyl)-glycine (M) and N-acetylcysteine (N) against lung injury caused by long-term exposure to cigarette smoke (CS) in mouse. C57BL6 mice were exposed to 12 cigarettes a day for 60 days and concomitantly treated with either one of the antioxidant drugs diluted in saline (CS+A-50 mg/kg; CS+M-200 mg/kg/day; CS+N-200 mg/kg/day). Control groups were sham-smoked (AA). Long-term CS exposure results in extensive parenchyma destruction in CS group. Both CS+N and CS+M groups showed preserved alveolar structure and showed preserved lung function when compared to CS group. Macrophage and neutrophil counts were decreased in CS+M, and CS+N groups when compared to CS group (p<0.05). Antioxidant enzyme activities were reduced in all treated groups. CS+A showed the highest reduction in catalase activity (-25%, p<0.01). We conclude that M treatment reduced long-term CS-induced inflammatory lung parenchyma destruction and lung function, comparable to N treatment, however, antioxidant administration did not reverse CS-induced antioxidant enzyme activity reduction.

Organ-related cigarette smoke-induced oxidative stress is strain-dependent.

BACKGROUND: Cigarette smoke (CS) is associated with oxidative stress in several organs because it contains high concentrations of free radicals and reactive oxygen species. Experimental models, using different strains, provide important insights into the genetic basis of diseases. This study sought to identify, in different mouse strains, the organ that is most-susceptible to CS-induced oxidative stress to obtain an optimized experimental animal model of oxidative injury induced by CS. MATERIAL/METHODS: Male Swiss, DBA/2, C3H, BALB/c, and C57BL/6 mice were exposed to CS 3 times a day (4 cigarettes per session) for 60 consecutive days. Control groups from the same strains were sham-treated. Protein content, malondialdehyde level, myeloperoxidase activity, and nitrite level were assayed in lung, liver, kidney, and brain from all strains. Catalase and glutathione peroxidase activities were measured. Analyses of data were done by using a 1-way ANOVA with Bonferroni's post-test (P<.05). RESULTS: Cigarette smoke exposure resulted in distinct, organ-specific responses among strains. The survival rate of DBA/2 mice was lowest. BALB/c and C57BL/6 strains were more-susceptible to oxidative damage in the lung and liver. C3H and C57BL/6 mice were more-susceptible to oxidative damage in the brain. No renal oxidative damage was seen. CONCLUSIONS: Mouse strains and individual organs display a range of susceptibilities to CS-induced oxidative stress. BALB/c and C57BL/6 strains appear to be the best choices as experimental models for studying CS effects on liver and lung, and C3H and C57BL/6 strains for CS-effects on the brain.

Restrição proteica na lactação como causa de hiperplasia da túnica média da aorta em ratos adultos / Maternal protein restriction during lactation induces tunica media hyperplasia in adult offspring

Objetivo: Investigar o efeito da restrição proteica neonatal na parede da aorta de ratos Wistar adultos. Métodos: As lactantes controle receberam ração padrão com 23 por cento de proteínas, enquanto as restritas receberam dieta isocalórica e hiprotéica(9 por cento) durante os 10 dias neonatais. A prole foi dividida em: Macho controle(MC), Fêmea controle(FC), Macho malnutrido(MM) e Fêmea malnutrida(FM). A massa corporal(BM) e a pressão arterial sistólica(PA) foram aferidas semanalmente. A eutanásia ocoreu na trigésima sexta semana de vida e anéis com 5 mm da aorta torácica foram removidos. Resultados: As alterações do MC foram: redução de 30 por cento nos grupos restritos aos 10 dias pós-natais, com recuperação parcial após restabelecimento de dieta-padrão, porém o grupo MM permaneceu com BM menor que o grupo MC(p menor 0,05) ao desmame. Os grupos MM e FM apresentaram aumento de 10 por cento da BM comparados aos grupos malnutridos. Dá vigésima quarta a trigésima sexta semana, a PA foi 16 por cento maoir no grupo MM(interação restrição proteica x sexo - two-way A NOVA, p menor 0,05). As aortas dos grupos malnutridos apresentaram maiores indicadores quantitativos do que os animais-controle: número de lamelas( 50 por cento em machos e 30 por cento em fêmeas), espessura da túnica média(ambos 25 por cento), densidade por área de núcleos de músculo liso(60 por cento) em machos e 35 por cento em fêmeas), densidade de volume de músculo liso(ambos 50 por cento) e densidade de área das lamelas(ambos 35 por cento). Conclusão: os dados sugerem remodelamento adverso da túnica média da aorta torácica em animais que sofreram restrição protéica neonatal, caracterizado por hiperplasia de células musculares lisas e de lamelas elásticas