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Objectives: Maternal physical activity may impact behavioral and electrophysiological aspects of brain function, with short- and long-term effects on pre- and postnatal neurodevelopment of the offspring. This study evaluated in the rat the effects of maternal voluntary physical activity (MVPA) on food intake and weight gain in the dams, as well as anxiety-like behavior, short-term memory and the brain excitability-related phenomenon known as cortical spreading depression (CSD) on the mother-pup dyad. Methods: Female Wistar rats (n=33) were individually housed in cages containing a running wheel for a 30-days adaptation period before mating. Rats were classified as inactive (I); active (A) or very active (VA) according to the distance spontaneously travelled daily. During gestation, the dams continued to have access to the running wheel. Mothers and their respective pups (1 pup per mother) were evaluated in the open field test (OFT), object recognition test (ORT), elevated plus maze test (EPMT) and the CSD propagation features. Results: MVPA was directly associated with increased food intake and weight gain during gestation, and maternal anxiolytic-like behavioral responses in the OFT. Pups from VA mothers showed a high discrimination index for shape recognition memory (ORT) and decreased propagation velocities of CSD, when compared with the inactive group. Discussion: The data suggest that MVPA during the gestational period induces neuroplasticity and may modulate the brain functions in the mother-infant dyad in the rat. [ABSTRACT FROM AUTHOR]

We investigated the influence of dietary omega-3 polyunsaturated fatty acids (n-3 PUFAs) on glutamatergic system modulation after a single episode of neonatal seizures and their possible effects on seizure-induced long-lasting behavioral deficits. Male Wistar rats receiving an omega-3 diet (n-3) or an n-3 deficient diet (D) from the prenatal period were subjected to a kainate-induced seizure model at P7. Glutamate transporter activity and immunocontents (GLT-1 and GLAST) were assessed in the hippocampus at 12, 24, and 48 h after the seizure episode. Fluorescence intensity for glial cells (GFAP) and neurons (NeuN) was assessed 24 h after seizure in the hippocampus. Behavioral analysis (elevated-plus maze and inhibitory avoidance memory task) was performed at 60 days of age. The D group showed a decrease in glutamate uptake 24 h after seizure. In this group only, the GLT1 content increased at 12 h, followed by a decrease at 24 h. GLAST increased up to 24 h after seizure. GFAP fluorescence was higher, and NeuN fluorescence decreased, in the D group independent of seizures. In adulthood, the D group presented memory deficits independent of seizures, but short-term memory (1.5 h after a training session) was abolished in the D group treated with kainate. N-3 PUFA positively influenced the glutamatergic system during seizure and prevented seizure-related memory deficits in adulthood. [ABSTRACT FROM AUTHOR]

Early-life adversity impacts on the offspring's brain development and is associated with a higher risk of developing age-associated diseases. In particular, perinatal protein malnutrition appears to be one of the most critical nutritional deficiencies affecting the individual's health and survival, but little is known about its effects on the persistence of behavioral alterations throughout life. Thus, the aim of the present study was to investigate how perinatal protein malnutrition impacts on age-related changes in the neuromuscular, cognitive and behavioral functions throughout life in a mouse model. One group of CF-1 dams received a normal-protein diet (NP: 20% casein) during gestation and lactation, whereas another group received a low-protein diet (LP: 10% casein). The offspring of both groups were analyzed by means of several behavioral tests at four different ages (young: 6–10 weeks old, mature: 22–26 weeks old, middle age: 39–43 weeks old, and old: 55–59 weeks old). Regarding neuromuscular functions, LP mice showed an early deterioration in muscular strength and a reduction in the body weight throughout life. Regarding behavior, while NP mice showed an age-related reduction of exploratory behavior, LP mice showed a constantly low level of this behavior, as well as high anxiety-like behavior, which remained at high levels throughout life. Regarding cognitive functions, LP mice showed deteriorated working memory at middle age. Finally, LP mice died 3.4 times earlier than NP mice. Analysis of the sex-related vulnerability showed that females and males were equally affected by perinatal protein malnutrition throughout life. Our results demonstrate that perinatal protein malnutrition induces enduring and age-related impairment behaviors, which culminate in higher death risk, affecting males and females equally. [ABSTRACT FROM AUTHOR]

Objectives: Oral gavage and time-restricted feeding are common delivery methods for dietary supplementation to rodents. However, the stress associated with selected feeding regimens could represent a confounding variable. In rodents, the adolescence period is particularly vulnerable to stressful events, in part related to ongoing maturation of the brain. In this context, omega-3 dietary supplementation has shown beneficial effects on neuronal growth, cognitive performance and stress regulation, while high-fat diet (HVF) has been associated with enhanced stress and anxiety. Therefore, this study has two aims: (1) evaluate the influence of 21-day supplementation with soybean oil (control group; CSO), fish oil (FO) or hydrogenated vegetable fat (HVF) fatty acids (FA) during the adolescence period on corticosterone secretion and anxiety-like behavior and, (2) compare the impact of dietary supplementation using oral gavage or time-limited feeding on these measures. Methods: Oral gavage or restricted feeding were used to daily feed adolescent rats (PND28–47; n = 49). On supplementation days 1, 7, 14 and 21, droplets of blood were collected for corticosterone (CORT) assessments. The Open Field (OFT) and the Elevated-Plus Maze (EPM) tests served to assess anxiety-like behavior on PND50. Results: Our findings indicate increased CORT secretion in restricted-(R) compared to gavage-fed animals on DAY7 and DAY14, suggesting heightened HPA-axis reactivity. Notably, CORT secretion diminished in FO-R-rats (DAY21), suggesting improved coping/adjustment. Consistent with CORT assessments, findings in the OFT and EPM supported attenuated anxiety in gavage versus restricted groups. FO and CSO supplementation reduced anxiety compared to HVF intake. Conclusions: Our findings uncover a significant impact of feeding methods on anxiety-like behavior and physiological stress response in rodents, supporting oral gavage as a less stressful option during the adolescent developmental stage. Supplement-specific effects on CORT secretion further indicated an influence of fish oil in regulating the stress response. [ABSTRACT FROM AUTHOR]

Objectives: Pyridoxine plays a key role in the development of the human nervous system. Several reports suggest that administration of high doses of pyridoxine can be helpful in improving disturbances such as anxiety and pyridoxine-dependent epilepsy, although it has also been associated with a proconvulsive action. In this study, we investigated in developing rats the effects of repeated administration of various doses of pyridoxine on anxiety-like behavior and the brain excitability-related phenomenon known as cortical spreading depression (CSD). Methods: From postnatal day (P) 7 to P27, Wistar rat pups received per gavage pyridoxine hydrochloride (1 mg/kg/day, or 5 mg/kg/day, or 10 mg/kg/day). On P60-70, the animals were tested in the elevated plus maze (EPM) to evaluate anxiety-like behavior. On P71-80, we recorded the CSD (4-hour recording session). Results: Compared with naïve (gavage-free) and saline-treated controls, pyridoxine-treated groups displayed a significant (p < 0.001) increase in CSD propagation velocity and amplitude of the CSD negative direct-current (DC)-shift, and a decrease in the CSD DC-shift duration. These effects were long-lasting and dose-dependent. In the EPM, no significant pyridoxine-associated effect was observed. Discussion: Our data demonstrate a novel action of pyridoxine on an electrical activity-related phenomenon (CSD) in the developing brain, confirming the hypothesis that the chronic treatment with pyridoxine early in life modulates CSD. Data on CSD propagation suggest that pyridoxine at a high dose might act as a prooxidant agent in the developing brain, a hypothesis that deserves further testing. [ABSTRACT FROM AUTHOR]

Background: Differences in the composition of control diets may confound outcomes in studies investigating dietary effects. Objective: We compared the effects of two control diets commonly used in mice studies, chow (SD) and a purified low-fat diet (LFD), in relation to a chronic high-fat diet (HFD). We hypothesized that SD and LFD will have similar effects on phenotypic, metabolic, and behavioral outcomes. Methods: Fifty-four 5-week-old male C57BL/6J mice were randomly assigned to one of the three dietary interventions (SD, LFD, or HFD) for 18 weeks. At week 16, mice were tested for behavioral changes. Glucose tolerance testing was conducted at week 17 and terminal blood collection at week 18. Results: SD and LFD mice exhibited no differences in cognitive performance on the Y-maze test and comparable anxiety-like behavior in the open-field and elevated zero maze tests. Significant declines in cognitive function and greater anxiety-like behavior were observed in the HFD group compared to both SD and LFD. Areas under the glucose tolerance curve were similar for SD and LFD, as were levels of high-density lipoprotein, triglycerides, cytokines, and adipocytokines. Only total cholesterol was significantly higher in LFD mice compared to SD mice. All measures were significantly higher in the HFD group. Discussion: Our data demonstrate that young mice develop similar phenotypic, metabolic, and behavioral profiles when fed SD vs. LFD. The two diets may thus be equally appropriate as controls for an HFD, although some studies may want to consider differences in effects on cholesterol levels. [ABSTRACT FROM AUTHOR]

Objectives: In the present study, effects of 3′,4′-dihydroxyflavonol (DiOHF) on anxiety-like behavior, and learning and memory were investigated in a model of transient global cerebral ischemia and reperfusion. Methods: The animals were assigned to sham-operated, ischemia, and two DiOHF-treated (10 mg/kg i.p.) groups. DiOHF was administered at 1 hour before and immediately after the ischemia. Male rats were subjected to bilateral common carotid artery occlusion to induce acute cerebral ischemia for 20 minutes, followed by reperfusion for 7 days. The openfield, elevated plus maze (EPM), and Morris water maze tests were used to evaluate the effects of DiOHF treatment on ischemia-induced locomotor activity, anxiety-like behavior, and spatial and recognition memory impairments, respectively. Results: In the open field test, locomotor activity in the ischemic rats was not altered 6 days after the ischemia, nor was anxiety-like behavior, which was evaluated with the EPM (P > 0.05). In the water-maze test, cerebral ischemia significantly decreased the exploration time in the target quadrant, and the platform crossing counts were lower (P < 0.05) in the probe trial test; this memory impairment was significantly improved by DiOHF applied 1 hour before and immediately after ischemia (P < 0.05). Discussion: All together, these findings suggest that DiOHF reverses spatial learning and memory deficits resulting from transient global ischemia but has no significant effect on anxiety-like behavior. [ABSTRACT FROM AUTHOR]

Some studies have showed the benefits of polyunsaturated fatty acids (PUFAs) as a complement in weight loss diets, even though the results are hardly conclusive. Additionally, anxiety is another relevant factor that influences not only the appetite but the locomotion of the animals as well. This study evaluated the effect of a diet enriched with PUFAs in relation to body weight in an animal model of anxiety (the elevated plus maze). Female Wistar rats were allocated to one of four groups and were fed different diets for 30 days: control diet (commercial chow (Nuvilab®); diet enriched with fish oil; diet enriched with linseed oil, and diet enriched with soybean oil. The body weight was not influenced by the kind of diet. The group that received food enriched with linseed oil remained in the open arms for longer periods when compared with the control group. This result suggests an anxiolytic-like effect in that group. [ABSTRACT FROM AUTHOR]