Effects of fluoxetine withdrawal in the brainstem and hypothalamus of overnourished rats: Chronic modulation on oxidative stress levels.

Poor nutritional quality in the early stages of development is associated with neurological diseases in adulthood. Studies showed that obesity-induced oxidative stress contributes to the genesis of neurological diseases through dysregulation of the brainstem and hypothalamus. Fluoxetine (Fx) is an antidepressant member in the family of selective serotonin reuptake inhibitors (SSRI) that can induce positive effects by reducing oxidative damage in brain tissues. We aimed to evaluate the late effect of Fx in the brainstem and hypothalamus of overnourished rats during development. Male Wistar rats, after birth, were randomly divided into the normal-nourished group (N, n = 9) and the overnourished group (O, n = 3). On the 39th day of life, the groups were subdivided into normofed, and the overnourished group treated or not with fluoxetine (10 mg/kg daily) (NF, NV, OF, and OV). All groups were treated from the 39th to the 59th day of life, and within 90 days, the tissues were collected for oxidative stress analysis. Briefly, our results showed that Fx treatment induced a tissue-dependent long-lasting effect in overfed animals, increasing the enzymatic defense (i.e., CAT and GST activity) in the hypothalamus, but more intensive, increasing the non-enzymatic defense (i.e., Total Thiols and GSH levels) in the brainstem. Overall, our study suggests that serotonin modulation at the final stage of brain development causes a long-lasting impact on brain structures in overfed rats at a different mode.

Maternal safflower oil consumption improve reflex maturation, memory and reduces hippocampal oxidative stress in the offspring rats treated during pregnancy and lactation.

OBJECTIVE: Evaluate the influence of maternal consumption of safflower oil on reflex maturation, memory and offspring hippocampal oxidative stress. METHODOLOGY: Two groups were formed: control group (C), whose mothers received a standard diet, and Safflower group (SF), whose mothers received a normolipidic diet with safflower oil as lipid source. Treatment was given from the 14th day of gestation and throughout lactation. To evaluate newborn development, the reflex ontogeny indicators between the 1st and the 21st days of life were evaluated; to assess memory, from the 42nd day of life on these animals were examined on open field habituation and novel object recognition test. Following behavioral analysis, the animals were anesthetized and decapitated. Hippocampus was rapidly dissected. In the hippocampal tissues, we evaluated the levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione S transferase (GST) and reduced glutathione (GSH). RESULTS: SF offspring showed delayed maturation of reflexes and improvement of novel object recognition in short-term and long-term (p < 0.05). Safflower oil decreases lipid peroxidation evaluated by MDA levels (p < 0.001) and increases antioxidant defenses as shown by SOD, CAT, GST and GSH levels (p < 0.05). In our study, the composition of flavonoids present in the oil was not evaluated. Furthermore, in a future study, the effect of maternal consumption on female offspring should be verified. CONCLUSION: Maternal intake of safflower oil could: (1) change neonate reflex parameters, (2) promote improvement of cognitive development in adolescence (3) improve antioxidant enzymatic and non-enzymatic defenses in the hippocampus.

Fish oil supplementation reverses behavioral and neurochemical alterations induced by swimming exercise in rats.

Diet and exercise are known to affect learning and memory. However, the effects of these interventions in the brain under development remains to be better investigated as the effects of high-intensity exercise. Moreover, it is still unclear how long the influence of diet and exercise lasts after the interventions are ceased. To investigate this, juvenile Wistar rats (30 days old) were supplemented with fish oil rich in polyunsaturated fatty acids (PUFAs) and performed swimming training for 50 days, 45 min per day, 5 times/week. The animals were assessed for locomotor activity with the open field test and for spatial memory with the object location task. To investigate neurochemical parameters such as fatty acids incorporation within the plasma membrane and brain-derived neurotrophic factor (BDNF) levels, the animals were euthanized, and the hippocampus dissected. These investigations were made at the end of the supplementation and exercise protocols and 21 days after the protocol has ended. Results indicate that high-intensity exercise impaired the spatial memory and decreased the levels of BDNF. Although supplementation led to PUFAs incorporation in plasma membrane, it did not prevent the harmful effect of exercise on memory. After 21 days of interruption, we observed that the supplementation reversed not only the deleterious effect of exercise on memory but also increased the BDNF levels. These results point to a complex influence of diet and exercise on spatial memory of juvenile rats, persisting after 21 days of interruption.

Safflower (Carthamus tinctorius L.) oil during pregnancy and lactation influences brain excitability and cortex oxidative status in the rat offspring.

OBJECTIVES: To evaluate how safflower oil (SFO) influences brain electrophysiology and cortical oxidative status in the offspring, mothers received a diet with SFO during brain development period. METHODS: Beginning on the 14th day of gestation and throughout lactation, rats received safflower (safflower group - SG) or soybean oil (control group - CG) in their diet. At 65 days old, cortical spreading depression (CSD) and cortex oxidative status were analyzed in the offspring. RESULTS: SG presented reduction of the CSD velocity as compared to the CG (SG: 3.24 ± 0.09; CG: 3.37 ± 0.07 mm/min). SFO reduced levels of lipid peroxidation by 39.4%. SG showed the following increases: glutathione-S-transferase, 40.8% and reduced glutathione, 34.3%. However, SFO decreased superoxide dismutase by 40.4% and catalase by 64.1%. To control for interhemispheric effects, since CSD was recorded only in the right cortex, we evaluated the oxidative status in both sides of the cortex; no differences were observed. DISCUSSION: Data show that when SFO is consumed by the female rats during pregnancy and lactation, the offspring present long-term effects on brain electrophysiology and cortical oxidative state. The present study highlights the relevance of understanding the SFO intake of pregnant and lactating mammals.

Can fish oil supplementation and physical training improve oxidative metabolism in aged rat hearts?

AIMS: It is well known that in the aging process a variety of physiological functions such as cardiac physiology and energy metabolism decline. Imbalance in production and elimination of reactive oxygen species (ROS) may induce oxidative stress. Research shows that oxidative stress is an important factor in the aging process. Studies suggest that É·-3 polyunsaturated fatty acids (PUFAs) and moderate physical exercise modulate the ROS system. Therefore, the present study aimed to investigate whether É·-3 present in fish oil supplementation coupled with moderate physical training could improve antioxidant and metabolic enzymes in the hearts of adult and aged rats and, if these effects could be associated to glycemia, plasma lipid profile or murinometric parameters. MAIN METHODS: Adult (weighing 315.1±9.3g) and aged rats (weighing 444.5±11.8g) exercised and receive fish oil supplementation for 4weeks. Then they were used to evaluate murinometric parameters, fasting glucose and lipid profile. After this, their hearts were collected to measure the levels of malondialdehyde (MDA), antioxidant enzyme activity (superoxide dismutase-SOD, catalase-CAT, glutathione peroxidase-GPx) and oxidative metabolism marker (citrate synthase-CS activity). KEY FINDINGS: Fish oil supplementation increases HDL concentration and activity of CAT and CS. Moreover, physical training coupled with fish oil supplementation induces additional effects on SOD, GPx and CS activity mainly in aged rats. SIGNIFICANCE: Our data suggest that combined treatment in aged rat hearts improves the antioxidant capacities and metabolic enzyme that can prevent the deleterious effects of aging.

Effects of glutamine supplementation on kidney of diabetic rat.

Glutamine is the most important donor of NH(3) in kidney playing an important role in acid-base buffering system. Besides this effect, glutamine presents many other relevant functions in the whole body, such as a precursor of arginine in adult and neonates. In addition to these effects, some studies have shown that glutamine can potentiate renal disease. In the present study, the effect of short-term treatment (15 days) with glutamine on control and diabetic rats was investigated. Using biochemical, histological and molecular biology analysis from control and diabetic rats we verified that glutamine supplementation increase in pro-inflammatory interleukins (IL)-1beta and IL-6 content in renal cortex and induce alteration in glomerular characteristics. This study showed that short-term treatment with glutamine in association with increased glucose levels could cause important alterations in glomerular morphology that may result in fast progression of kidney failure.

Glutamine supplementation prevents exercise-induced neutrophil apoptosis and reduces p38 MAPK and JNK phosphorylation and p53 and caspase 3 expression.

We have previously shown that a single session of exercise induces DNA fragmentation, mitochondrial membrane depolarization, increases expression of pro-apoptotic genes (bax and bcl-xS) and decreases expression of anti-apoptotic genes (bcl-xL) in rat neutrophils. Glutamine supplementation had a protective effect in the apoptosis induced by a single session of exercise. The mechanism involved in the effect of single session of exercise to induce apoptosis was investigated by measuring expression of p53 and caspase 3 and phosphorylation of p38 mitogen-activated protein kinases (MAPK) and cJun NH(2)-terminal kinase (JNK) in neutrophils from rats supplemented or not with glutamine. Exercise was carried out on a treadmill for 1 h and the rats were killed by decapitation. Neutrophils were obtained by intraperitoneal (i.p.) lavage with PBS, 4 h after injection of oyster glycogen solution. Glutamine supplementation (1g per Kg b.w.) was given by gavage 1 h before the exercise session. Gene expression and protein phosphorylation were then analyzed by reverse transcriptase chain reaction (RT-PCR) and Western blotting, respectively. A single session of exercise increased p38 MAPK and JNK phosphorylation and p53 and caspase 3 expression. Glutamine supplementation partially prevented the increase in p38 MAPK and JNK phosphorylation and p53 expression, and fully abolished the increase in caspase 3 expression. Thus, neutrophil apoptosis induced by a single session of exercise is accompanied by increased p53 and caspase 3 expression and p38 MAPK and JNK phosphorylation. Glutamine supplementation prevents these effects of exercise and reduces apoptosis.

Função e apoptose do neutrófilo: modulação pela maturação sexual, exercício e suplementação com glutamina / Neutrophil function and apoptosis: modulation by sexual maturation, exercise and glutamine supplementation

O efeito de uma única sessão de exercício (a 85% da capacidade máxima) na função e apoptose de neutrófilos de ratos de 60 (imaturos sexualmente) e 90 (maduro sexualmente) dias foi estudado. Avaliou-se também o efeito da suplementação com glutamina (1g por kg de peso) na prevenção das alterações induzidas pelo exercício. As funções estudadas foram: capacidade fagocitária, produção de óxido nítrico (NO) e de espécies reativas de oxigênio (EROs). Para avaliar a morte de neutrófilos, os seguintes parâmetros foram determinados: integridade de membrana, condensação de cromatina, fragmentação de DNA, externalização de fosfatidilserina, potencial transmembrânico mitocondrial, expressão de genes anti-apoptóticos (bcl-xL), próapoptóticos (bax e bcl-xS) e caspase 3. A maturação sexual por si só reduziu a capacidade fagocitária, aumentou a expressão dos componentes (gp91, p47 e p22phox) da NADPH-oxidase e aumentou a produção de óxido nítrico (NO). Além disso, a maturação sexual aumentou a proporção de células em apoptose, conforme observado pelo aumento na fragmentação de DNA e despolarização mitocondrial, redução na expressão de Bcl-xL e aumento da expressão de caspase 3. A sessão de exercício, reduziu a produção de NO e aumentou a expressão dos componentes da NADPHoxidase nos neutrófilos de ratos de 90 dias. Em ratos de 60 dias, o exercício não alterou as funções dos neutrófilos (capacidade fagocitária, produção de óxido nítrico e de espécies reativas de oxigênio - EROs). A sessão de exercício aumentou a proporção de neutrófilos em apoptose em ratos de 60 e 90 dias. A suplementação oral com glutamina aumentou a capacidade fagocitária e a produção de EROs nos neutrófilos de ratos de 60 dias e a expressão dos componentes da NADPH-oxidase nos neutrófilos de ratos de 90 dias. Além disso, a suplementação com glutamina reduziu o efeito do exercício na indução de apoptose nos neutrófilos dos ratos de 60 e 90 dias.

The effect of a single session of intense exercise (85% maximal capacity) on apoptosis and function of neutrophils from 60 (sexually immature) and 90 (sexually mature) days-old rats was examined. The possible effect of glutamine supplementation (1 g per kg body weight) to prevent the changes induced by the exercise was also investigated. The functions studied were: phagocytic capacity, nitric oxide (NO) and reactive oxygen species (ROS) production. To evaluate the process of neutrophils death, the following parameters were determined: cell viability, chromatin condensation, DNA fragmentation, phosphatidylserine externalization, mitocondrial transmembrane potential, expression of anti-apoptotic (bcl-xL) and pro-apoptotic (bax, bcl-xS and caspase 3) genes. The sexual maturation per se decreased the phagocytic capacity, raised the expression of the NADPH-oxidase components (gp91, p47 and p22phox) and increased nitric oxide (NO) production. In addition, sexual maturation increased the proportion of cells in apoptosis as indicated by the increase in DNA fragmentation, mitochondrial depolarization and in caspase expression, and a reduction in bcl-xL expression. The exercise session decreased NO production and increased the expression of the NADPH-oxidase components in neutrophils from 90 days old rats. In 60 days old rats, the exercise did not affect neutrophil functions studied: phagocytic capacity, NO and reactive oxygen species (ROS) production. The exercise raised the proportion of neutrophils in apoptosis in both 60 and 90 days-old rats. Oral glutamine supplementation raised the phagocytic capacity and reactive oxygen species (ROS) production in neutrophils from 90 days old rats. In addition, glutamine supplementation decreased the effect of exercise on the induction of apoptosis in neutrophils from both 60 and 90 days old rats.

Beneficial effect of glutamine on exercise-induced apoptosis of rat neutrophils.

INTRODUCTION/PURPOSE: The effect of a single bout of intensive exercise on apoptosis of rat neutrophils and the possible prevention by glutamine administration was examined. The experiments were performed in sexually immature and sexually mature male rats as to examine the possible involvement of sexual maturation in the effect of exercise. METHODS: Exercise was carried out on a treadmill for 1 h before rats were killed by decapitation. Aqueous solution of glutamine was given by gavage (1 g.kg-1 body weight), 1 h before exercise. Neutrophils were obtained by intraperitoneal lavage with phosphate-buffered saline (PBS), 4 h after injection of oyster glycogen solution. The cells were then analyzed for apoptosis by flow cytometry and fluorescence microscopy. Pro- and antiapoptotic gene expression was evaluated by reverse transcriptase chain reaction (RT-PCR). RESULTS: Neutrophils obtained from immature and mature exercised rats showed an increase in DNA fragmentation, chromatin condensation, and phosphatidylserine externalization. This suggests that all neutrophils suffered apoptosis. To study the possible mechanism involved, the production of reactive oxygen metabolites, expression of genes involved in apoptosis and mitochondrial transmembrane potential were examined. Acute exercise raised reactive oxygen metabolites production by neutrophils. Exercise did not change the expression of antiapoptotic (bcl-xL) and apoptotic (bax and bcl-xS) genes in neutrophils from immature rats but caused a significant increase of bax and bcl-xS expression and provoked a significant decrease of bcl-xL expression in cells from mature rats. Exercise also induced a marked loss of mitochondrial depolarization in neutrophils. Oral glutamine supplementation partially prevented the exercise-induced apoptosis in neutrophils from sexually immature and mature rats. CONCLUSION: The protective effect of glutamine on neutrophil apoptosis induced by acute exercise possibly occurs by preservation of mitochondrial function.