Maturation Of Reflexes Research Articles

Memory is improved and reflex maturation accelerated in the progeny of rat dams that consumed pequi (Caryocar Brasiliense)

Memory is improved and reflex maturation accelerated in the progeny of rat dams that consumed pequi (Caryocar Brasiliense)

Neonatal high-dose riboflavin treatment channels energy expenditure towards sensorimotor and somatic development and reduces rodent growth and weight gain by modulating NRF-1 in the hypothalamus

Metabolic adaptations early in life can drive energy expenditure towards brain and physical development, with less emphasis on body mass gain and somatic growth. Dietary or pharmacological manipulations can influence these processes, but to date, the effects provided by riboflavin have not been studied. The study aimed to evaluate the effects of neonatal treatment with different doses of riboflavin on sensorimotor and somatic development in rodents. Based on this, the following experimental groups were formed: Control (C, 0 mg/kg), Riboflavin 1 (R1, 1 mg/kg), Riboflavin 2 (R2, 10 mg/kg) and Riboflavin 3 (R3, 100 mg/kg). Treatment with 100 mg/kg riboflavin anticipated the reflex ontogeny of righting, cliff aversion, negative geotaxis, and free-fall righting. Intervention with 10 and 100 mg/kg of riboflavin anticipated the reflex maturation of vibrissae placement. Eye-opening, upper incisor eruption, and lower incisor eruption reached maturational age more quickly for animals treated with 100 mg/kg, while caudal growth and body weight gain were reduced from the second week of treatment, for groups R2 and R3. Pearson's correlation analysis indicated a positive association between the administration of high doses of riboflavin and murine growth in the first week of treatment. There was, however, a negative association between treatment with a high dose of riboflavin and growth in the second week of administration, coinciding with a reduction in body weight gain in the R3 group. Treatment with 100 mg/kg of riboflavin also reduced energy expenditure parameters in the open field and catwalk. Although high-dose treatment stimulates the physiological plasticity of the CNS and reduces weight gain, hepatic parameters were preserved, highlighting the participation of the liver in the supply of fatty acids for neural maturation. Furthermore, hypothalamic NRF-1 expression was increased in the R3 group inversely to the reduction in weight gain. Our results suggest that high-dose riboflavin stimulates sensorimotor and somatic development and reduces the energy invested in growth, body weight gain, and locomotor activity, possibly involving NRF-1 gene modulation in the hypothalamus.

Референтные интервалы в репродуктивной токсичности крыс Вистар

The need to risk assessment of reproductive and ontogenetic toxicity of a medicine depends on a number of factors such as the properties of the drug, indications for use and the target patient population. It should be noted that this type of research is widespread. To increase the reliability of the of research data interpretation, the evaluation of the results should include not only comparison with control values, but also with reference values obtained in the same test center. The purpose of the study was the creation of reference intervals for the main indicators evaluated in studies of developmental and reproductive toxicity for Wistar rats. To calculate the reference intervals, the data obtained in the course of research at RMC “HOME OF PHARMACY” in the period from 2015 to 2021. Animals of the control groups were used to calculate the reference intervals. All manipulations and experiments are approved by the bioethical commission. Prenatal development was assessed by indicators: the number of live and dead fetuses, corpus luteum, implantation sites, pre- and post-implantation death was calculated. In the postnatal period, body weight was measured weekly in rat pups, a number of physiological parameters and the rate of maturation of sensory-motor reflexes were evaluated. For the data, a nonparametric method for determining reference intervals was applied. The most variable indicators are the number of implantation sites, the percentage of pre- and post-implantation death and the time of testicular descent, which must be taken into account when analyzing the data obtained. It is shown that the values of reference intervals obtained by us are generally comparable with the literature data.

Promoting Survival and Primitive Reflexes to Prevent Brain Imbalance in Premature Infants: A Scoping Review of New Insights by Physiotherapists on Developmental Disorders.

Survival reflexes, originating from the brainstem, are involuntary motor responses that are present at birth and facilitate the survival of the neonate. The age of the baby is critical enough to give information about the maturation of these reflexes. In the case of preterm babies, the delayed maturity of these reflexes may pose a threat to the life of the newborn. One can perceive what the baby can feel, taste, smell, see, and hear through reflex maturation. The objective was to identify and understand the role of survival reflexes and primitive reflexes and their importance in premature children. PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), ProQuest, The Cochrane Library, Scopus, and Web of Science were the electronic databases used from January 2017 until November 2022. We included the original articles, reviews, and randomized clinical trials that focused on the importance of survival reflexes. Later on, all the articles were systematically arranged as per the information they provided, and 101 titles were selected, of which 32 met the inclusion criteria. Various articles were written regarding the present literature about primitive reflexes, but none promoted them in the neonatal intensive care unit (NICU). This review is regarding the use of survival reflexes to improve the outcomes of neonates, specifically in the NICU. Simple interactions with the environment are made possible by primitive reflexes, which also serve as the foundation for early movement. This review presents a better understanding of the maturation of survival reflexes and primitive reflexes and provides further insight into how a physiotherapist can concentrate on the early identification and development of these reflexes to prevent further complications. Assessing the primitive reflex in the NICU will help in the early identification of developmental delay and further help us predict reflex maturation. Promoting them will provide positive outcomes in terms of neonatal development. A physiotherapist can play a vital role starting from the NICU to get the baby into an environment similar to the mother's womb and therapy to get the early maturation of the reflex.

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

ObjectiveEvaluate the influence of maternal consumption of safflower oil on reflex maturation, memory and offspring hippocampal oxidative stress. MethodologyTwo 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). ResultsSF 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. ConclusionMaternal 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.

Milk fat globule membrane supplementation to obese rats during pregnancy and lactation promotes neurodevelopment in offspring via modulating gut microbiota.

Pre-pregnancy obesity and high-fat diet (HFD) during pregnancy and lactation are associated with neurodevelopmental delay in offspring. This study aimed to investigate whether milk fat globule membrane (MFGM) supplementation in obese dams could promote neurodevelopment in offspring. Obese female rats induced by HFD were supplemented with MFGM during pregnancy and lactation. Maternal HFD exposure significantly delayed the maturation of neurological reflexes and inhibited neurogenesis in offspring, which were significantly recovered by maternal MFGM supplementation. Gut microbiota analysis revealed that MFGM supplementation modulated the diversity and composition of gut microbiota in offspring. The abundance of pro-inflammatory bacteria such as Escherichia shigella and Enterococcus were down-regulated, and the abundance of bacteria with anti-inflammatory and anti-obesity functions, such as Akkermansia and Lactobacillus were up-regulated. Furthermore, MFGM alleviated neuroinflammation by decreasing the levels of lipopolysaccharides (LPS) and pro-inflammatory cytokines in the circulation and brain, as well as inhibiting the activation of microglia. Spearman’s correlation analysis suggested that there existed a correlation between gut microbiota and inflammation-related indexes. In conclusion, maternal MFGM supplementation promotes neurodevelopment partly via modulating gut microbiota in offspring.

Study of Reproductive Toxicity of the Liposomal Photosensitizer Lipophthalocyan.

Study of embryotoxicity, teratogenicity and reproductive toxicity of the new drug Lipophtalocyan in rats. Studies were conducted on 210 non-inbred female rats and 105 non-inbred male rats. The drug was administered daily via i. v. injection for 48 days (males) and for 15 days (females) in 2 total doses corresponding to the therapeutic dose (TD) for mice when converted to rats and 10 TD. When mating with intact female rats, no changes in sexual behavior were observed, but the index of the ability to fertilize and conceive decreased when compared to the values of the control group by 35-40% (TD index=60%) and by 75-80% (10 TD index=20%). The index of the ability to fertilize and conceive differed from the values of the control group by 90% (TD index=5%) and by 15% (10 TD index=80%). There were no differences in the indicator of embryotoxicity and teratogenicity in intact and drug-treated female rats, compared with the control group. Lipophtalocyan has a negative effect on the male and female reproductive function in rats and has an embryotoxic effect according to the index of the ability to fertilize and conceive, as well as the indices of preimplantation and post-implantation fetal death. The drug does not have a teratogenic effect, neither it affects the physical development of offspring or the rate of maturation of sensory-motor reflexes during feeding.

Effects of high-fat diet intake during perinatal period on reflex-ontogeny and intestinal morphometry of rat offspring

Reflex-ontogeny and intestinal morphometrics were evaluated in Wistar rats whose mothers were fed on a high-fat diet during the perinatal period. Male pups (n=52) formed four experimental groups: NN (pups from mothers with lab chow diet during gestation and lactation); NH (pups from mothers with lab chow diet during pregnancy and high-fat in lactation); HH (pups from mothers with high-fat diet during gestation and lactation); HN (pups from mothers with high-fat diet during pregnancy and lab chow in lactation). The reflex ontogeny, the maturation of physical characteristics and parameters of somatic growth were evaluated during lactation. In addition, the body mass index (BMI), the specific rate of weight gain (SRWG), the Lee index, the weight of the brain and intestinal parameters were analyzed after weaning. High-fat diet during pregnancy (HH and HN groups) delayed the maturation of reflexes and physical characteristics. The high-fat diet affected somatic growth differently, reducing somatic growth parameters in the groups NH and HH and increasing in the HN group. The highest SRWG was found in group HN. SRWG and BMI were reduced in the groups NH and HH. The relative intestinal weight was reduced in the groups NH, HH and HN. The relative length of small intestine was longer in group HN than in group NN. The total height of the mucosa and size of the villous were lower in group HH than in group NN. In conclusion, high-fat diet promoted negative consequences for the development of the nervous and enteric systems of the offspring.

The Behavior and Postnatal Development in Infant and Juvenile Rats After Ultrasound-Induced Chronic Prenatal Stress.

Fetal development is susceptible to environmental factors. One such factor is exposure to stress during pregnancy. The present study aimed to investigate the effects of chronic prenatal stress (PS) on the development and behavior of rat offspring during infancy and juvenile ages. Existing approaches to modeling prenatal stress on animals do not correlate with the main type of stress in pregnant women, namely psychological stress. We used a new stress paradigm in the experiment, namely, stress induced by exposure to variable frequency ultrasound (US), which acted on pregnant Wistar rats on gestational days 1–21. This type of stress in rodents can be comparable to psychological stress in humans. We assessed physical development, reflex maturation, motor ability development, anxious behavior, response to social novelty, and social play behavior in male and female offspring. Additionally, we investigated maternal behavior and the effect of neonatal handling (NH) on behavior. Prenatal stress did not affect postnatal developmental characteristics in rat pups, but prenatally stressed rats had higher body weight in early and adult age than controls. Prenatal exposure to a stressor increased anxiety in the open-field test (OF), changed social preferences in the social novelty test (SN), and impaired social play behavior in males. Neonatal handling reduced anxiety and restored social behavior, but evoked hyperactive behavior in rat pups. Maternal behavior did not change. Our study demonstrated for the first time that exposure to variable frequency ultrasound during pregnancy influences offspring development and impairs behavior, correlating with the effects of other types of stress during pregnancy in rodents. This supports the idea of using this exposure to model prenatal stress.

Impact of neonatal anoxia and hypothermic treatment on development and memory of rats

Therapeutic hypothermia (TH) is well established as a standard treatment for term and near-term infants. However, therapeutic effects of hypothermia following neonatal anoxia in very premature babies remains inconclusive. The present rodent model of preterm neonatal anoxia has been shown to alter developmental milestones and hippocampal neurogenesis, and to disrupt spatial learning and memory in adulthood. These effects seem to be reduced by post-insult hypothermia. Epigenetic-related mechanisms have been postulated as valuable tools for developing new therapies. Dentate gyrus neurogenesis is regulated by epigenetic factors. This study evaluated whether TH effects in a rodent model of preterm oxygen deprivation are based on epigenetic alterations. The effects of TH on both developmental features (somatic growth, maturation of physical characteristics and early neurological reflexes) and performance of behavioral tasks at adulthood (spatial reference and working memory, and fear conditioning) were investigated in association with the possible involvement of the epigenetic operator Enhancer of zeste homolog 2 (Ezh2), possibly related to long-lasting effects on hippocampal neurogenesis. Results showed that TH reduced both anoxia-induced hippocampal neurodegeneration and anoxia-induced impairments on risk assessment behavior, acquisition of spatial memory, and extinction of auditory and contextual fear conditioning. In contrast, TH did not prevent developmental alterations caused by neonatal anoxia and did not restore hippocampal neurogenesis or cause changes in EZH2 levels. In conclusion, despite the beneficial effects of TH in hippocampal neurodegeneration and in reversing disruption of performance of behavioral tasks following oxygen deprivation in prematurity, these effects seem not related to developmental alterations and hippocampal neurogenesis and, apparently, is not caused by Ezh2-mediated epigenetic alteration.

Effects of the aqueous extract of Phyllanthus niruri Linn during pregnancy and lactation on neurobehavioral parameters of rats’ offspring

Ethnopharmacological relevancePhyllanthus niruri L. (Phyllanthaceae) is a plant used in traditional medicine, mainly to treat kidney stones. However, the effects of maternal exposure to P. niruri remain poorly explored. Aim of the studyThe objective of this study was to investigate the effects of administration of aqueous extract of P. niruri (AEPN) during pregnancy and lactation, in maternal toxicity, reflex maturation, and offspring memory. Materials and methodsPregnant rats were divided into three groups (n = 8/group): Control (vehicle), AEPN 75, and AEPN 150 (each respectively treated with P. niruri at a dose of 75 and 150 mg/kg/day). The animals were treated via intragastric gavage during pregnancy and lactation. Weight gain, feed intake, and reproductive performance were analyzed in the mothers. In the offspring, the following tests were performed: Neonatal Reflex Ontogeny, Open Field Habituation Test and the Object Recognition Test in adulthood. ResultsMaternal exposure to AEPN did not influence weight gain, feed intake, or reproductive parameters. In the offspring, anticipation of reflex ontogenesis (time of completion) was observed (p < 0.05). During adulthood, the AEPN groups presented decreases in exploratory activity upon their second exposure to the Open Field Habituation Test (in a dose-dependent manner) (p < 0.05). In the Object Recognition Test, administration of the extract at 75 and 150 mg/kg induced significant dose-dependent improvements in short and long-term memory (p < 0.05). ConclusionAdministration of the AEPN accelerated the reflex maturation in neonates, and improved offspring memory while inducing no maternal or neonatal toxicity.

Maternal exposure to busulfan reduces the cell number in the somatosensory cortex associated with delayed somatic and reflex maturation in neonatal rats

Busulfan is a bifunctional alkylating agent used for myeloablative conditioning and in the treatment of chronic myeloid leukemia due to its ability to cause DNA damage. However, in rodent experiments, busulfan presented a potential teratogenic and cytotoxic effect. Studies have evaluated the effects of busulfan on fetuses after administration in pregnancy or directly on pups during the lactation period. There are no studies on the effects of busulfan administration during pregnancy on offspring development after birth. We investigated the effects of busulfan on somatic and reflex development and encephalic morphology in young rats after exposure in pregnancy. The pregnant rats were exposed to busulfan (10 mg/kg, intraperitoneal) during the early developmental stage (days 12–14 of the gestational period). After birth, we evaluated the somatic growth, maturation of physical features and reflex-ontogeny during the lactation period. We also assessed the effects of busulfan on encephalic weight and cortical morphometry at 28 days of postnatal life. As a result, busulfan-induced pathological changes included: microcephaly, evaluated by the reduction of cranial axes, delay in reflex maturation and physical features, as well as a decrease in the morphometric parameters of somatosensory and motor cortex. Thus, these results suggest that the administration of a DNA alkylating agent, such as busulfan, during the gestational period can cause damage to the central nervous system in the pups throughout their postnatal development.

Potential biomarkers for neuroinflammation and neurodegeneration at short and long term after neonatal hypoxic-ischemic insult in rat

BackgroundHypoxic-ischemic (HI) encephalopathy causes life-long morbidity and premature mortality in term neonates. Therapies in addition to whole-body cooling are under development to treat the neonate at risk for HI encephalopathy, but are not a quickly measured serum inflammatory or neuronal biomarkers to rapidly and accurately identify brain injury in order to follow the efficacy of therapies.MethodsIn order to identify potential biomarkers for early inflammatory and neurodegenerative events after neonatal hypoxia-ischemia, both male and female Wistar rat pups at postnatal day 7 (P7) were used and had their right carotid artery permanently doubly occluded and exposed to 8% oxygen for 90 min. Sensory and cognitive parameters were assessed by open field, rotarod, CatWalk, and Morris water maze (MWM) test. Plasma and CSF biomarkers were investigated on the acute (24 h and 72 h) and chronic phase (4 weeks). Brains were assessed for gene expression analysis by quantitative RT-PCR Array.ResultsWe found a delay of neurological reflex maturation in HI rats. We observed anxiolytic-like baseline behavior in males more than females following HI injury. HI rats held on the rotarod for a shorter time comparing to sham. HI injury impaired spatial learning ability on MWM test. The CatWalk assessment demonstrated a long-term deficit in gait parameters related to the hind paw. Proinflammatory biomarkers such as IL-6 in plasma and CCL2 and TNF-α in CSF showed an upregulation at 24 h after HI while other cytokines, such as IL-17A and CCL5, were upregulated after 72 h in CSF. At 24 h post-injury, we observed an increase of Edn1, Hif1-α, and Mmp9 mRNA levels in the ipsilateral vs the contralateral hemisphere of HI rats. An upregulation of genes involved with clotting and hematopoietic processes was observed 72 h post-injury.ConclusionsOur work showed that, in the immature brain, the HI injury induced an early increased production of several proinflammatory mediators detectable in plasma and CSF, followed by tissue damage in the hypoxic hemisphere and short-term as well as long-lasting neurobehavioral deficits.

Effect of Conjugated Linoleic Acid on Memory and Reflex Maturation in Rats Treated During Early Life.

In the critical period of neurodevelopment (gestation and lactation), maternal consumption of essential fatty acids (FAs) can alter the offspring cognitive function permanently causing damage. Lipids can regulate neurotrophin and compose brain tissue. However, the effects of maternal consumption of a mixture of conjugated linoleic acid (CLA) on an offspring nervous system are not completely clear. We aimed to investigate the impacts of different CLA concentrations mixed into the maternal diet during early life on neonatal reflex maturation and cognitive functions of the offspring. Three groups were formed: control (CG): receiving a standard diet; CLA1: receiving a diet containing 1% of CLA, and CLA3: receiving a diet containing 3% of CLA, offered during gestation and lactation. After birth, the reflex responses of the offspring were observed from the 1st to the 21st day. After weaning, the animals’ anxiety and memory were assessed using open field (OF) and novel object recognition tests. Fatty acids in the breast milk and the offspring’s brain were also quantified. The data were analyzed using one-way ANOVA and the Kruskal–Wallis test. CLA1 presented accelerated palmar grasp disappearance versus CLA3 and negative-geotaxis versus CG; and the CLA3 presented increases for most reflexes (cliff-avoidance, vibrissa-placing, negative-geotaxis, and auditory-startle response), and decrease in reflexes palmar grasp and free-fall righting versus CG (p < 0.05). CLA3 group explored less of the OF in the second exposure. CLA1 and CLA3 presented an increased exploration ratio for new objects, which indicates memory improvement. The milk tested from CLA3 demonstrated an increase in polyunsaturated fatty acids (PUFAs), and a decrease in monounsaturated fatty acids. The amount of CLA in milk was greater in CLA1 and CLA3 and in the brain offspring both presented moderated amounts of CLA. Maternal treatment with the CLA mixture induced anticipated reflex maturation and improved memory in the offspring. Even though CLA was detected in the brains in only trace amounts, offspring’s brain PUFA and SFA levels were increased. Further studies aimed to delineate the effect of maternal CLA supplementation on offspring’s brain lipid metabolism and long-term neurologic outcome are needed to confirm these findings.

Maternal Supplementation With Avocado (Persea americana Mill.) Pulp and Oil Alters Reflex Maturation, Physical Development, and Offspring Memory in Rats.

Avocado (Persea americana Mill.) is an oleaginous fruit source of fatty acids with high levels of neuroprotective phytocomplexes. The objective of this study was to evaluate the development of reflex and somatic maturation, fatty acid profiles in the brain, and memory in different stages of life in the offspring of dams supplemented with avocado pulp and oil during gestation and lactation. The dams were randomly divided into three groups (n = 15 pups/group), and recieved by gavage supplementation: control group (CG)–distilled water; Avocado Oil (AO)−3,000 mg avocado oil/kg animal weight, and Avocado Pulp (AP)−3,000 mg avocado pulp/kg animal weight. We performed the following tests: Analysis of Somatic Development and Ontogeny of Postnatal Reflex (T0 to T21), the Open Field Habituation Test and the Object Recognition Test (ORT) in the adolescent (T45) and adult (T90) phases. The cerebral fatty acids content was evaluated at times T0, T21, T45, and T90. The results were analyzed using the statistical program GraphPad Prism and significant statistics were considered when p < 0.05. Acceleration of reflex maturation and reflex ontogeny was observed in the offspring of AO and AP fed dams, with the results being more pronounced in the pulp fed group (p < 0.05). All groups presented a decrease in the ambulation parameter in the second exposure to the Open Field Habituation Test, at T45 and T90 (p < 0.05). In the ORT, the AO and AP offspring presented memory improvements in the short and long term in the adult and adolescent phases (p < 0.05). The results of the brain fatty acid profiles presented higher polyunsaturated fatty acids (PUFA) content in the AO and AP groups at T21, T45, and T90. The docosahexaenoic fatty acid (DHA) content was higher at T21 (AO and AP), at T45 (AO and AP), and at T90 (AP) (p < 0.05). The arachidonic acid (ARA) content was higher at T45 (AO and AP), and at T90 (AO) (p < 0.05). Maternal supplementation with avocado oil and pulp anticipates reflex maturation and somatic postnatal development, and improves memory during the adolescent and adult phases.

The effects of a maternal advanced glycation end product-rich diet on somatic features, reflex ontogeny and metabolic parameters of offspring mice.

Maternal exposure to a Western type diet during pregnancy might predispose the offspring to manifestation of metabolic and behavioral disturbances in later life. The Western type diet contains large amounts of advanced glycation end products (AGEs). In humans and experimental rodents, the intake of an AGE-rich diet (AGE-RD) negatively affected glucose homeostasis, and initiated the production of reactive oxygen species. Rats consuming the AGE-RD presented changes in behavior. It remains unclear whether maternal intake of the AGE-RD might affect developmental plasticity in offspring. We examined early somatic (weight, incisor eruption, ear unfolding, and eye opening) and neuromotor development, oxidative status, insulin sensitivity (HOMA index) and locomotor activity assessed in PhenoTyper cages in the offspring of mice fed during pregnancy with either the AGE-RD (25% bread crusts/75% control chow) or control chow. Until weaning, the somatic development of offspring did not differ between the two dietary groups. The AGE-RD offspring manifested physiological reflexes (auditory startle, eye lid, ear twitch and righting reflexes) earlier. As young adults, the male offspring of the AGE-RD dams were heavier and less insulin sensitive compared with their control counterparts. The AGE-RD offspring showed higher locomotor activity during the active phase. Our data indicate that the maternal AGE-RD during pregnancy might accelerate the maturation of reflexes in offspring, predispose the male progeny to weight gain and affect their glucose homeostasis. These effects manifest without the direct consumption of the AGE-RD by offspring. Further work is needed to determine the mechanisms by which the maternal AGE-RD affects neurobehavioral pathways in offspring, as well as sex differences in adverse metabolic responses.

Maternal voluntary physical activity attenuates delayed neurodevelopment in malnourished rats.

What is the central question of this study? In the present study, a reproducible model of maternal voluntary physical activity was developed to evaluate the adaptive response of physical activity by attenuating the effects of maternal undernutrition on physical features, reflex ontogeny and growth trajectory of offspring during development. What is the main finding and its importance? Maternal physical activity may induce neuronal maturation of sensorimotor connections impacting on the patterns of locomotor activity in malnourished offspring. Thus, physical activity should be considered as a therapeutic means of countering the effects of maternal undernutrition, by providing a useful strategy for enhancing the neuronal activity of children born to mothers who experience a restricted diet during pregnancy. This study evaluated the effects of maternal voluntary physical activity during pregnancy and lactation on somatic growth (SG), reflex ontogeny (RO) and locomotor activity (LA) of rats whose mothers were protein restricted. Virgin female Wistar rats were divided into the following six groups: control, normal protein (C-NP, n=4); control, low protein (C-LP, n=4); inactive, normal protein (I-NP, n=8); inactive, low protein (I-LP, n=7); very active, normal protein (VA-NP, n=8); and very active, low protein (VA-LP, n=6). Voluntary physical activity was recorded daily in dams. The LP groups were fed an 8% casein diet, whereas control groups were fed a 17% casein diet during pregnancy and lactation. Offspring were evaluated in terms of SG (body weight and length, latero-lateral skull axis and anteroposterior head axis) and RO (palmar grasp, righting, free-fall righting, negative geotaxis, cliff avoidance, auditory startle response and vibrissa placing). The LA was evaluated at 23, 45 and 60days old in the open field. Voluntary physical activity was reduced during pregnancy and lactation independent of the maternal diet. Pups from LP dams showed delayed SG, reflex maturation and patterns of LA when compared with control pups. The C-LP and I-LP pups showed a delayed SG, RO and LA. Pups from VA-LP mothers showed no delay in SG and RO and presented a faster development of patterns of LA. Maternal voluntary physical activity attenuated the effects of LP diet on indicators of neurodevelopment and patterns of LA of offspring.

Maternal intake of cashew nuts accelerates reflex maturation and facilitates memory in the offspring

Essential fatty acids, being indispensable during the stages of pregnancy, lactation and infancy influence the transmission of nerve impulses and brain function, and cashew nuts are a good source of these fatty acids. The objective of this study was to evaluate the effects of cashew nut consumption on reflex development, memory and profile of fatty acids of rat offspring treated during pregnancy and lactation. The animals were divided into three groups: Control (CONT), treated with 7% lipid derived from soybean oil; Normolipidic (NL) treated with 7% lipids derived from cashew nuts; and Hyperlipidic (HL) treated with 20% lipids derived from cashew nuts. Reflex ontogeny, Open-field habituation test and the Object Recognition Test (ORT) were assessed. The profile of fatty acids in the brain was carried out when the animals were zero, 21 and 60days old. Accelerated reflex maturation was observed in animals treated with cashew nuts (p<0.05). NL presented better memory in the Open-field habituation test; the NL and HL showed improvement of short-term memory in the ORT, but long term damage in HL (p<0.05). The results of the lipid profile of the brain at the end of the experiment showed an increase in levels of saturated fatty acids and less Docosahexaenoic acid (DHA) in animals of the HL. The data showed that maternal consumption of cashew nuts can accelerate reflex maturation and facilitate memory in offspring when offered in adequate quantities.

Pregnancy swimming causes short- and long-term neuroprotection against hypoxia-ischemia in very immature rats.

BackgroundHypoxia-ischemia (HI) is a major cause of neurological damage in preterm newborn. Swimming during pregnancy alters the offspring's brain development. We tested the effects of swimming during pregnancy in the very immature rat brain.MethodsFemale Wistar rats (n=12) were assigned to the sedentary (SE, n=6) or the swimming (SW, n=6) group. From gestational day 0 (GD0) to GD21 the rats in the SW group were made to swim for 20 min/day. HI on postnatal day (PND) 3 rats caused sensorimotor and cognitive impairments. Animals were distributed into SE sham (SESH), sedentary HIP3 (SEHI), swimming sham (SWSH), and swimming HIP3 (SWHI) groups. At PND4 and PND5, Na+/K+-ATPase activity and brain-derived neurotrophic factor (BDNF) levels were assessed. During lactation and adulthood, neurological reflexes, sensorimotor, anxiety-related, and cognitive evaluations were made, followed by histological assessment at PND60.ResultsAt early stages, swimming caused an increase in hippocampal BDNF levels and in the maintenance of Na+/K+-ATPase function in the SWHI group. The SWHI group showed smaller lesions and the preservation of white matter tracts. SEHI animals showed a delay in reflex maturation, which was reverted in the SWHI group. HIP3 induced spatial memory deficits and hypomyelination in SEHI rats, which was reverted in the SWHI group.ConclusionSwimming during pregnancy neuroprotected the brains against HI in very immature neonatal rats.

Effects of Maternal Stress during Different Periods of Pregnancy on the Early Neurobehavioral Response of Rats

Background: Several studies focus on the effects of prenatal stress in adulthood. Relatively little is known about the early neurodevelopmental consequences of such experiences and their predictive value. Thus we examined the early neurobehavioral responses of offspring whose mothers were exposed to restraint stress. Methods and results: Pregnant rats were exposed to 60 minutes restraint stress twice a day for seven days in different periods of pregnancy (early/mid and late phase). After birth, offspring were examined for the maturation of neural signs and reflexes daily for 3 weeks. Mid-pregnancy stress resulted in a subtle faster development in the appearance of eyelid and auditory startle reflexes, and in the disappearance of crossed extensor reflex. Pups exposed to stress in the last week of intrauterine life displayed a delay in air righting and showed a slight enhancement in the appearance of auditory startle. Conclusion: Based on our present findings, the deleterious consequences of prenatal stress are not apparent during the early developmental stages at least not detectable with the battery of test most widely used to examine neurobehavioral development. However, these findings draw the attention of the need of careful awareness in later ages in spite of the normal neurobehavioral development of newborns exposed to prenatal stress.