Neonatal kaempferol exposure attenuates impact of cerebral palsy model on neuromotor development, cell proliferation, microglia activation, and antioxidant enzyme expression in the hippocampus of rats.

OBJECTIVES: This study aims to assess the effect of neonatal treatment with kaempferol on neuromotor development, proliferation of neural precursor cells, the microglia profile, and antioxidant enzyme gene expression in the hippocampus. METHODS: A rat model of cerebral palsy was established using perinatal anoxia and sensorimotor restriction of hindlimbs during infancy. Kaempferol (1 mg/ kg) was intraperitoneally administered during the neonatal period. RESULTS: Neonatal treatment with kaempferol reduces the impact of the cerebral palsy model on reflex ontogeny and on the maturation of physical features. Impairment of locomotor activity development and motor coordination was found to be attenuated by kaempferol treatment during the neonatal period in rats exposed to cerebral palsy. Neonatal treatment of kaempferol in cerebral palsy rats prevents a substantial reduction in the number of neural precursor cells in the dentate gyrus of the hippocampus, an activated microglia profile, and increased proliferation of microglia in the sub-granular zone and in the granular cell layer. Neonatal treatment with kaempferol increases gene expression of superoxide dismutase and catalase in the hippocampus of rats submitted to the cerebral palsy model. DISCUSSION: Kaempferol attenuates the impact of cerebral palsy on neuromotor behavior development, preventing altered hippocampal microglia activation and mitigating impaired cell proliferation in a neurogenic niche in these rats. Neonatal treatment with kaempferol also increases antioxidant defense gene expression in the hippocampus of rats submitted to the cerebral palsy model.

Effects of riboflavin in the treatment of brain damage caused by oxygen deprivation: an integrative systematic review.

Brain oxygen deprivation causes morphological damage involved in the formation of serious pathological conditions such as stroke and cerebral palsy. Therapeutic methods for post-hypoxia/anoxia injuries are limited and still have deficiencies in terms of safety and efficacy. Recently, clinical studies of stroke have reported the use of drugs containing riboflavin for post-injury clinical rehabilitation, however, the effects of vitamin B2 on exposure to cerebral oxygen deprivation are not completely elucidated. This review aimed to investigate the potential antioxidant, anti-inflammatory and neuroprotective effects of riboflavin in cerebral hypoxia/anoxia. After a systematic search, 21 articles were selected, 8 preclinical and 12 clinical studies, and 1 translational study. Most preclinical studies used B2 alone in models of hypoxia in rodents, with doses of 1-20 mg/kg (in vivo) and 0.5-5 µM (in vitro). Together, these works suggested greater regulation of lipid peroxidation and apoptosis and an increase in neurotrophins, locomotion, and cognition after treatment. In contrast, several human studies have administered riboflavin (5 mg) in combination with other Krebs cycle metabolites, except one study, which used only B2 (20 mg). A reduction in lactic acidosis and recovery of sensorimotor functions was observed in children after treatment with B2, while adults and the elderly showed a reduction in infarct volume and cognitive rehabilitation. Based on findings from preclinical and clinical studies, we conclude that the use of riboflavin alone or in combination acts beneficially in correcting the underlying brain damage caused by hypoxia/anoxia and its inflammatory, oxidative, and behavioral impairments.

Therapeutic advances for treating memory impairments in perinatal brain injuries with implications for cerebral palsy: a systematic review and meta-analysis of preclinical studies.

Cerebral palsy (CP) is a neurodevelopmental disorder caused by damage to the immature brain. CP is considered the main cause of physical disability in childhood. Studies have shown that memory function and emotional behaviour are significantly impaired in CP. Current thought is that interventions for neuromotor damaged play a prominent role, but neglects the memory acquisition problems that affect the functioning and quality of life of these children. This systematic review aims to map and analyse pre-clinical interventions used to treat memory formation problems resulting from CP. For this, a search was carried out in the Pubmed, Web of Science, Scopus and Lilacs databases. Then, eligibility, extraction date and evaluation of the methodological quality of the studies were determined. 52 studies were included in this review, and 27 were included in a meta-analysis. Assessing memory performance as a primary outcome, and structural and biochemical changes in the hippocampus as a secondary outcome. CP models were reported to be induced by hypoxia-ischemia, oxygen deprivation and liposaccharide (LPS) exposure, resulting in impairments in the formation of short-term and long-term memory in adult life. A reduction in escape latency and dwell time were observed in the target quadrant as well as an increase in the time needed for the rodents to find the platform in the Morris Water Maze (MWM). Brain injuries during the perinatal period are considered an insult that negatively impacts hippocampus maturation and causes impairment in memory formation in adult life. Some studies reported that regions of the hippocampus such as the dentate gyrus and cornu ammonis 1 were impaired in CP, noting an increase in oxidative stress enzymes and pro-inflammatory cytokines, associated with a reduction in BDNF and neurogenesis levels. These were reported to cause a reduction in the number of neurons and the volume of the hippocampus, in addition to an increase in astrogliosis and apoptosis of neurons and difficulties in forming new memories similar to those that occur in children with CP. Interventions that reduced neuroinflammation and the presence of free radicals were highlighted as a therapy for the memory disturbance present in CP. Preclinical studies registered treatments with oxygen interventions, resveratrol and erythropoietin, which were able to reduce the damage to the hippocampus and promote improvements in memory and behaviour. In the meta-analysis of selected studies, we observed favorable results, through effect size, for the use of oxygen interventions (SDM -6.83 95% CI [-7.91, -5.75], Z = 12.38, p = 0.03; I2 = 71%), erythropoietin (SDM -3.16 95% CI [-4.27, -2.05], Z = 5.58, p = 0.002; I2 = 82%) and resveratrol (SDM -2.42 95% CI [-3.19, - 1.66], Z = 6.21, p = 0.01; I2 = 77%), stimulating plastic responses in the hippocampus and facilitating the memory formation, with these presenting positive effects in general (SDM -2.84 95% CI [-3.10, -2.59], Z = 22.00; p < 0.00001; I2 = 92.9%). These studies demonstrate possible avenues of intervention for memory alterations in experimental models of early brain injuries, highlighting promising interventions that can facilitate the maturation of the hippocampus and memory formation and, consequently, minimize functional problems that arise during development.

Neonatal treatment with fluoxetine alters locomotor activity and the cortical glial/neuron index in rats with cerebral palsy.

Cerebral palsy (CP) is characterized by motor disorders, including deficits in locomotor activity, coordination, and balance. Selective serotonin reuptake inhibitors have been shown to play an important role in brain plasticity. This study investigates the effect of neonatal treatment using fluoxetine on locomotor activity and histomorphometric parameters of the primary somatosensory cortex (S1) in rats submitted to an experimental model of CP. CP was found to reduce bodyweight and locomotion parameters and also to increase the glia/neuron index in the S1. Administration of fluoxetine 10 mg/kg reduced bodyweight, impaired locomotor activity parameters, and increased the number of glial cells and the glia/neuron ratio in the S1 in rats with CP. However, treatment with fluoxetine 5 mg/kg was not found to be associated with adverse effects on locomotor activity and seems to improve histomorphometric parameters by way of minor changes in the S1 in animals with CP. These results thus indicate that experimental CP, in combination with the use of a high dose of fluoxetine (10 mg/kg), impairs locomotor and histomorphometric parameters in the S1, while treatment with a low dose of fluoxetine (5 mg/kg) averts the negative outcomes associated with a high dose of fluoxetine in relation to these parameters but produces no protective effect.

Neonatal kaempferol exposure attenuates gait and strength deficits and prevents altered muscle phenotype in a rat model of cerebral palsy.

Cerebral palsy (CP) is characterized by brain damage at a critical period of development of the central nervous system, and, as a result, motor, behavioural and learning deficits are observed in those affected. Flavonoids such as kaempferol have demonstrated potential anti-inflammatory and neuroprotective properties for neurological disorders. This study aimed to assess the effects of neonatal treatment with kaempferol on the body development, grip strength, gait performance and morphological and biochemical phenotype of skeletal muscle in rats subjected to a model of CP. The groups were formed by randomly allocating male Wistar rats after birth to four groups as follows: C = control treated with vehicle, K = control treated with kaempferol, CP = CP treated with vehicle and CPK = CP treated with kaempferol. The model of CP involved perinatal anoxia and sensorimotor restriction of the hind paws during infancy, from the second to the 28th day of postnatal life. Treatment with kaempferol (1 mg/kg) was performed intraperitoneally during the neonatal period. Body weight and length, muscle strength, gait kinetics and temporal and spatial parameters were evaluated in the offspring. On the 36th day of postnatal life, the animals were euthanized for soleus muscle dissection. The muscle fibre phenotype was assessed using the myofibrillar ATPase technique, and the muscle protein expression was measured using the Western blot technique. A reduction in the impact of CP on body phenotype was observed, and this also attenuated deficits in muscle strength and gait. Treatment also mitigated the impact on muscle phenotype by preventing a reduction in the proportion of oxidative fibres and in the histomorphometric parameters in the soleus muscle of rats in the CP group. The results demonstrate that neonatal treatment with kaempferol attenuated gait deficits and impaired muscle strength and muscle maturation in rats subjected to a model of CP.

Dietary flavonoid kaempferol reduces obesity-associated hypothalamic microglia activation and promotes body weight loss in mice with obesity.

BACKGROUND: Obesity results from an unbalance in the ingested and burned calories. Energy balance (EB) is critically regulated by the hypothalamic arcuate nucleus (ARC) by promoting appetite or anorectic actions. Hypothalamic inflammation, driven by high activation of the microglia, has been reported as a key mechanism involved in the development of diet-induced obesity. Kaempferol (KF), a flavonoid-type polyphenol present in a large number of fruits and vegetables, was shown to regulate both energy metabolism and inflammation. OBJECTIVES: In this work, we studied the effects of both the central and peripheral treatment with KF on hypothalamic inflammation and EB regulation in mice with obesity. METHODS: Obese adult mice were chronically (40 days) treated with KF (0.5 mg/kg/day, intraperitoneally). During the treatment, body weight, food intake (FI), feed efficiency (FE), glucose tolerance, and insulin sensitivity were determined. Analysis of microglia activation in the ARC of the hypothalamus at the end of the treatment was also performed. Body weight, FI, and FE changes were also evaluated in response to 5µg KF, centrally administrated. RESULTS: Chronic administration of KF decreased ∼43% of the density, and ∼30% of the ratio, of activated microglia in the arcuate nucleus. These changes were accompanied by body weight loss, decreased FE, reduced fasting blood glucose, and a tendency to improve insulin sensitivity. Finally, acute central administration of KF reproduced the effects on EB triggered by peripheral administration. CONCLUSION: These findings suggest that KF might fight obesity by regulating central processes related to EB regulation and hypothalamic inflammation.

Locomotion is impacted differently according to the perinatal brain injury model: Meta-analysis of preclinical studies with implications for cerebral palsy.

BACKGROUND: Different approaches to reproduce cerebral palsy (CP) in animals, contribute to the knowledge of the pathophysiological mechanism of this disease and provide a basis for the development of intervention strategies. Locomotion and coordination are the main cause of disability in CP, however, few studies highlight the quantitative differences of CP models, on locomotion parameters, considering the methodologies to cause brain lesions in the perinatal period. METHODS: Studies with cerebral palsy animal models that assess locomotion parameters were systematically retrieved from Medline/PubMed, SCOPUS, LILACS, and Web of Science. Methodological evaluation of included studies and quantitative assessment of locomotion parameters were performed after eligibility screening. RESULTS: CP models were induced by hypoxia-ischemia (HI), Prenatal ischemia (PI), lipopolysaccharide inflammation (LPS), intraventricular haemorrhage (IVH), anoxia (A), sensorimotor restriction (SR), and a combination of different models. Overall, 63 studies included in qualitative synthesis showed a moderate quality of evidence. 16 studies were included in the quantitative meta-analysis. Significant reduction was observed in models that combined LPS with HI related to distance traveled (SMD -7.24 95 % CI [-8.98, -5.51], Z = 1.18, p < 0.00001) and LPS with HI or anoxia with sensory-motor restriction (SMD -6.01, 95 % CI [-7.67, -4.35], Z = 7.11), or IVH (SMD -4.91, 95 % CI [-5.84, -3.98], Z = 10.31, p < 0.00001) related to motor coordination. CONCLUSION: The combination of different approaches to reproduce CP in animals causes greater deficits in locomotion and motor coordination from the early stages of life to adulthood. These findings contribute to methodological refinement, reduction, and replacement in animal experimentation, favoring translational purposes.

A systematic review of neurogenesis in animal models of early brain damage: Implications for cerebral palsy.

Brain damage during early life is the main factor in the development of cerebral palsy (CP), which is one of the leading neurodevelopmental disorders in childhood. Few studies, however, have focused on the mechanisms of cell proliferation, migration, and differentiation in the brain of individuals with CP. We thus conducted a systematic review of preclinical evidence of structural neurogenesis in early brain damage and the underlying mechanisms involved in the pathogenesis of CP. Studies were obtained from Embase, Pubmed, Scopus, and Web of Science. After screening 2329 studies, 29 studies, covering a total of 751 animals, were included. Prenatal models based on oxygen deprivation, inflammatory response and infection, postnatal models based on oxygen deprivation or hypoxic-ischemia, and intraventricular hemorrhage models showed varying neurogenesis responses according to the nature of the brain damage, the time period during which the brain injury occurred, proliferative capacity, pattern of migration, and differentiation profile in neurogenic niches. Results mainly from rodent studies suggest that prenatal brain damage impacts neurogenesis and curbs generation of neural stem cells, while postnatal models show increased proliferation of neural precursor cells, improper migration, and reduced survival of new neurons.

Early life fluoxetine treatment causes long-term lean phenotype in skeletal muscle of rats exposed to maternal lard-based high-fat diet.

There is a concern about early life exposure to Selective Serotonin Reuptake Inhibitors (SSRI) in child development and motor system maturation. Little is known, however, about the interaction of environmental factors, such as maternal nutrition, associated with early exposure to SSRI. The increased maternal consumption of high-fat diets is worrisome and affects serotonin system development with repercussions in body phenotype. This study aimed to assess the short- and long-term effects of neonatal fluoxetine treatment on the body and skeletal muscle phenotype of rats exposed to a maternal lard-based high-fat (H) diet during the perinatal period. A maternal lard-based high-fat diet causes reduced birth weight, a short-term reduction in type IIA fibers in the soleus muscle, and in type IIB fibers in the Extensor Digitorum Longus (EDL) muscle, reducing Lactate Dehydrogenase (LDH) activity in both muscles. In the long-term, the soleus showed reduced muscle weight, smaller area and perimeter of muscle fibers, while the EDL muscle showed reduced Citrate Synthase (CS) activity in offspring from the rats on the maternal lard-based high-fat diet. Early-life exposure to fluoxetine reduced body weight and growth and reduced soleus weight and enzymatic activity in young rats. Exposure to neonatal fluoxetine in adult rats caused a decreased body mass index, less food intake, and reduced muscle weight with reduced CS and LDH activity. Neonatal fluoxetine in young rats exposed to a maternal lard-based high-fat diet caused reduced body weight and growth, reduced soleus weight as well as area and perimeter of type I muscle fibers. In adulthood, there was a reduction in food intake, increased proportion of IIA type fibers, reduced area and perimeter of type IIB, and reduction in levels of CS activity in EDL muscle. Neonatal fluoxetine treatment in rats exposed to a maternal lard-based, high-fat diet induces a reduction in muscle weight, an increase in the proportion of oxidative fibers and greater oxidative enzymatic activity in adulthood.

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.

Selective serotonin reuptake inhibitors affect structure, function and metabolism of skeletal muscle: A systematic review.

Selective Serotonin Reuptake Inhibitors (SSRIs) may have side effects, such as stiffness, tremors and altered tonic activity, as well as an increased risk of developing insulin resistance and diabetes mellitus. However, little is known about the structural, functional and metabolic changes of skeletal muscle after administration of SSRIs. The aim of this systematic review was to explore and discuss the effects of SSRIs on skeletal muscle properties described in human and rodent studies. A systematic search of PUBMED, SCOPUS, and WEB OF SCIENCE was performed. The inclusion criteria were intervention studies in humans and rodents that analysed the effects of SSRIs on skeletal muscle properties. The research found a total of six human studies, including two randomized controlled trials, one non-randomized controlled trial, one uncontrolled before-after study and two case reports, and six preclinical studies in rodents. Overall, the studies in humans and rodents showed altered electrical activity in skeletal muscle function, assessed through electromyography (EMG) and needle EMG in response to chronic treatment or local injection with SSRIs. In addition, rodent studies reported that SSRIs may exert effects on muscle weight, the number of myocytes and the cross-sectional area of skeletal muscle fibre. The results showed effects in energy metabolism associated with chronic SSRI use, reporting altered levels of glycogen synthase activity, acetyl-CoA carboxylase phosphorylation, citrate synthase activity, and protein kinase B Ser phosphorylation. Moreover, changes in insulin signalling and glucose uptake were documented. In this context, we concluded based on human and rodent studies that SSRIs affect electrical muscle activity, structural properties and energy metabolism in skeletal muscle tissue. However, these changes varied according to pre-existing metabolic and functional conditions in the rodents and humans.

Perinatal undernutrition associated to experimental model of cerebral palsy increases adverse effects on chewing in young rats.

The aim of the present study was to investigate the effect of perinatal undernutrition on the sensorimotor pattern of chewing in rats submitted to cerebral palsy experimental model. A total of 60 male Wistar rats were randomly distributed into four groups: Nourished/Control (NC, n=15), Nourished/Cerebral Palsy (NCP, n=15); Undernourished/Control (UC, n=15) and Undernourished/Cerebral Palsy (UCP, n=15). Animals of cerebral palsy (CP) group were subjected to an experimental model based on the combination of perinatal anoxia associated with sensorimotor restriction of the hindlimb. In the rats were evaluated body weight gain, intake of breast milk, feed post-weaning consumption, parameters of the chewing, intra-oral sensitivity and muscle properties (muscle weight and distribution of types of fibers) of the masseter and digastric. Animals from undernourished CP group showed greater reduction in most data evaluated including body weight (P<0.05), food intake post-weaning (P<0.05), frequency of chewing cycles (P<0.05), duration of the reactions of "taste" (P<0.05), muscle weight and decrease of the proportion of type IIB fibers in the masseter muscle (P<0.05). These results demonstrated in rats submitted a cerebral palsy that perinatal undernutrition intensifies the damage in morphological and functional parameters of chewing.