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1.
Brain Behav Immun ; 121: 303-316, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39098438

RESUMO

BACKGROUND: Cerebral Palsy (CP) is a major cause of motor and cognitive disability in children due to injury to the developing brain. Early intensive sensorimotor rehabilitation has been shown to change brain structure and reduce CP symptoms severity. We combined environmental enrichment (EE) and treadmill training (TT) to observe the effects of a one-week program of sensorimotor stimulation (EETT) in animals exposed to a CP model and explored possible mechanisms involved in the functional recovery. METHODS: Pregnant Wistar rats were injected with Lipopolysaccharide (LPS - 200 µg/kg) intraperitoneally at embryonic days 18 and 19. At P0, pups of both sexes were exposed to 20' anoxia at 37 °C. From P2 to P21, hindlimbs were restricted for 16 h/day during the dark cycle. EETT lasted from P21 to P27. TT - 15 min/day at 7 cm/s. EE - 7 days in enriched cages with sensorimotor stimulus. Functional 3D kinematic gait analysis and locomotion were analyzed. At P28, brains were collected for ex-vivo MRI and histological assessment. Neurotrophins and key proteins involved in CNS function were assessed by western blotting. RESULTS: CP model caused gross and skilled locomotor disruption and altered CNS neurochemistry. EETT reversed locomotor dysfunction with minor effects over gait kinematics. EETT also decreased brain inflammation and glial activation, preserved myelination, upregulated BDNF signaling and modulated the expression of proteins involved in excitatory synaptic function in the brain and spinal cord. CONCLUSIONS: Using this translational approach based on intensive sensorimotor rehabilitation, we highlight pathways engaged in the early developmental processes improving neurological recovery observed in CP.


Assuntos
Paralisia Cerebral , Modelos Animais de Doenças , Locomoção , Plasticidade Neuronal , Ratos Wistar , Animais , Paralisia Cerebral/reabilitação , Paralisia Cerebral/fisiopatologia , Plasticidade Neuronal/fisiologia , Ratos , Feminino , Locomoção/fisiologia , Masculino , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Gravidez , Recuperação de Função Fisiológica/fisiologia , Encefalite/metabolismo , Encefalite/fisiopatologia , Encefalite/reabilitação , Marcha/fisiologia , Condicionamento Físico Animal/fisiologia , Condicionamento Físico Animal/métodos , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/fisiopatologia
2.
Reproduction ; 166(2): 89-97, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37204211

RESUMO

In brief: The containers used in cell cryopreservation are essential to maintain cell integrity and viability after thawing. This paper reveals the methodology of using biodegradable containers for fish sperm cryopreservation. Cryopreserved sperm in biodegradable containers showed high fertility capability. Biodegradable capsules could be alternative containers to plastic straws for sperm cryopreservation. Abstract: Containers used to cryopreserve sperm are made with non-biodegradable plastic compounds, having a high monetary and environmental cost. Therefore, the development of biodegradable alternative containers for cell cryopreservation is necessary. Thus, this study aimed to evaluate the efficiency of hard-gelatin and hard-hydroxypropyl methylcellulose (HPMC) capsules as low-cost and biodegradable alternative containers for sperm cryopreservation. Sperm from 12South American silver catfish Rhamdia quelen were individually cryopreserved in plastic straws 0.25 mL (as control), hard-gelatin, and hard-HPMC capsules. The quality of post-thaw sperm cryopreserved in the different containers was checked by measuring spermatozoa membrane integrity, kinetic parameters, mitochondrial activity, fertilization, hatching, and normal larvae rates. The samples cryopreserved in straws showed a higher percentage of membrane integrity (68%) than those frozen in hard-gelatin (40%) and hard-HPMC capsules (40%). However, we did not observe differences between the samples stored in straws and hard capsules for the rest of the tested sperm parameters. Thus, based on the high sperm fertility capability, both capsules were efficient as cryopreservation containers for maintaining sperm functionality.


Assuntos
Gelatina , Preservação do Sêmen , Animais , Masculino , Cápsulas , Motilidade dos Espermatozoides , Sêmen , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Criopreservação/veterinária , Criopreservação/métodos , Espermatozoides
3.
J Fish Biol ; 103(1): 13-21, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37060354

RESUMO

Colouring has a great influence on the commercialization of ornamental fish. The aim of this study was to evaluate different concentrations of canthaxanthin in the diet of the blood swordtail Xiphophorus helleri in an effort to obtain a more intense red colour. Six concentrations of canthaxanthin (0, 50, 100, 250, 400 and 600 mg kg-1 diet) were used. The experiment lasted 60 days. Fish were evaluated for increased red pigmentation through the use of photographs (performed by smartphone) and imaging applications considering the Hunter method and the CMYK and productive performance. No significant differences were observed for productive performance. The use of photographs by means of a smartphone and the use of imaging applications proved to be adequate to assess differences in colour in the species. Swordtail red pigmentation did not show significant increase regardless of canthaxanthin dosages. Varieties of ornamental fish bred for red coloration may have limits for increased colour due to the storage capacity of carotenoids by chromatophores.


Assuntos
Cantaxantina , Ciprinodontiformes , Animais , Cor , Carotenoides , Dieta/veterinária
4.
Int J Mol Sci ; 24(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37958562

RESUMO

Neonatal hypoxic-ischemic (HI) encephalopathy (HIE) in term newborns is a leading cause of mortality and chronic disability. Hypothermia (HT) is the only clinically available therapeutic intervention; however, its neuroprotective effects are limited. Lactoferrin (LF) is the major whey protein in milk presenting iron-binding, anti-inflammatory and anti-apoptotic properties and has been shown to protect very immature brains against HI damage. We hypothesized that combining early oral administration of LF with whole body hypothermia could enhance neuroprotection in a HIE rat model. Pregnant Wistar rats were fed an LF-supplemented diet (1 mg/kg) or a control diet from (P6). At P7, the male and female pups had the right common carotid artery occluded followed by hypoxia (8% O2 for 60') (HI). Immediately after hypoxia, hypothermia (target temperature of 32.5-33.5 °C) was performed (5 h duration) using Criticool®. The animals were divided according to diet, injury and thermal condition. At P8 (24 h after HI), the brain neurochemical profile was assessed using magnetic resonance spectroscopy (1H-MRS) and a hyperintense T2W signal was used to measure the brain lesions. The mRNA levels of the genes related to glutamatergic excitotoxicity, energy metabolism and inflammation were assessed in the right hippocampus. The cell markers and apoptosis expression were assessed using immunofluorescence in the right hippocampus. HI decreased the energy metabolites and increased lactate. The neuronal-astrocytic coupling impairments observed in the HI groups were reversed mainly by HT. LF had an important effect on astrocyte function, decreasing the levels of the genes related to glutamatergic excitotoxicity and restoring the mRNA levels of the genes related to metabolic support. When combined, LF and HT presented a synergistic effect and prevented lactate accumulation, decreased inflammation and reduced brain damage, pointing out the benefits of combining these therapies. Overall, we showed that through distinct mechanisms lactoferrin can enhance neuroprotection induced by HT following neonatal brain hypoxia-ischemia.


Assuntos
Hipotermia , Hipóxia-Isquemia Encefálica , Fármacos Neuroprotetores , Animais , Feminino , Masculino , Ratos , Animais Recém-Nascidos , Encéfalo/patologia , Hipóxia-Isquemia Encefálica/patologia , Inflamação/patologia , Ácido Láctico/metabolismo , Lactoferrina/farmacologia , Lactoferrina/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos Wistar , RNA Mensageiro
5.
J Fish Biol ; 102(1): 119-127, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36217919

RESUMO

Endemic to the south-west Atlantic Ocean, the shortnose guitarfish (Zapteryx brevirostris) is a small species, classified as endangered by the IUCN. Although reproduction in captivity has been successful for some species, a range of factors can limit the success of captive breeding programmes for elasmobranchs. In Brazil, the Ubatuba Aquarium was the first public aquarium to reproduce small-sized elasmobranchs. Since 2018, at least five parturition events have been recorded for Z. brevirostris at the institution. From a total of 13 live neonates that rearing was attempted, the mean ± standard error of weight, total length (TL) and disc width at birth were 17.47 ± 1.6 g, 13.25 ± 0.7 cm and 6.53 ± 0.2 cm, respectively. The mean weight as well as mean TL were higher for females at all births, with 26.15 g and 15.07 cm for females in comparison with 17.09 g and 13.94 cm for males. Considering the increasing risk of extinction that the species is facing, age and growth studies are fundamental for the success of conservation, improving the knowledge of Z. brevirostris life cycle so that a more efficient and sustainable management can be carried out. This study provides important data, as well as directions for captive breeding of the species.


Assuntos
Elasmobrânquios , Rajidae , Feminino , Masculino , Animais , Gravidez , Reprodução , Parto , Brasil
6.
J Fish Biol ; 103(3): 635-645, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37296364

RESUMO

The andrological study of a species involves the macro- and microscopic analyses of the internal reproductive organs and the evaluation of seminal parameters and ultrastructural characteristics of the spermatozoa. As in other vertebrates, the male reproductive tract in chondrichthyans consists of testes and reproductive ducts (efferent duct, epididymis, Leydig's gland, ductus deferens and seminal vesicle). In this study the authors used three adult specimens of Zapteryx brevirostris from wild capture kept at the Ubatuba Aquarium, Brazil. Semen was collected by abdominal massage over the location of the seminal vesicle, preceded by ultrasonographic evaluation. The semen collected was diluted 1:200 and subject to quantitative and morphological analyses. Ultrastructural analysis was performed using transmission and scanning electron microscopy. Correlation was observed between successful collection and ultrasonographic image of an engorged seminal vesicle, as well as testicles with easily delimitable margins and higher echogenicity. It was possible to identify free spermatozoa with helical filiform appearance, as well as spermatozeugmata. The average sperm concentration resulted in 5 million packets per millilitre and 140 million spermatozoa per millilitre. The sperm nucleus is described as follows: cone shaped, parachromatin sheath less dense than the chromatin of the nucleus, smooth depression of the nuclear fossa, abaxial axoneme 9 + 2 and accessory axonemal columns in positions 3 and 8 and oval shaped, with flattened inner surface in cross-section. These results broaden the knowledge of the andrology of this species, contributing to ex situ breeding programmes.


Assuntos
Andrologia , Rajidae , Masculino , Animais , Sêmen , Genitália Masculina/ultraestrutura , Espermatozoides/ultraestrutura , Testículo/anatomia & histologia , Peixes
7.
Zoo Biol ; 42(5): 675-682, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37171149

RESUMO

There are only a few studies that describe the larval development of Echinaster or aspects on culture systems for the genus. For starfishes, the choice of suitable substrates has received special attention since it could influence the acid-base balance of the water, movement capacity and predation rate. The objective of this study was to evaluate the ideal food-related substrate for the rearing of juvenile Echinaster brasiliensis. A batch of fertilized eggs released in spontaneous spawning was collected and kept in a plankton-kreisel until metamorphosis. Data on preference of food-related substrate was recorded for 10 weeks from day 58 post-release. From release to 132 days old, arm length increased from 0.81 mm to 1.31 ± 0.03 mm. Considering the sudden increase in arm length (AL), it was estimated that feeding started around 40 days of age. Regarding food-related substrate preferences, biofilm grown on "rocks" showed a significant difference among other treatments, adding up to 50% of preference (p < .05). For sponge and biofilm from bio media, there was no statistical difference for the whole period. In this study, sponges showed to be the least preferred food-related substrate for post-settlement juveniles. Considering that Echinaster and other starfish are commonly maintained on a diet of collected or cultured sponges, difficulties in sourcing a ready supply throughout the year represent limitations to their sole use within commercial or laboratory-scale production. In this sense, the use of biofilm from biological media for the feeding of juvenile starfish is not yet reported in the literature and showed to be an easy and promising option.


Assuntos
Animais de Zoológico , Estrelas-do-Mar , Animais , Preferências Alimentares , Dieta/veterinária
8.
Metab Brain Dis ; 37(7): 2315-2329, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35778625

RESUMO

Therapeutic hypothermia (TH) is the standard treatment for neonatal hypoxia-ischemia (HI) with a time window limited up to 6 h post injury. However, influence of sexual dimorphism in the therapeutic window for TH has not yet been elucidated in animal models of HI. Therefore, the aim of this study was to investigate the most effective time window to start TH in male and female rats submitted to neonatal HI. Wistar rats (P7) were divided into the following groups: NAÏVE and SHAM (control groups), HI (submitted to HI) and TH (submitted to HI and TH; 32ºC for 5 h). TH was started at 2 h (TH-2 h group), 4 h (TH-4 h group), or 6 h (TH-6 h group) after HI. At P14, animals were subjected to behavioural tests, volume of lesion and reactive astrogliosis assessments. Male and female rats from the TH-2 h group showed reduction in the latency of behavioral tests, and decrease in volume of lesion and intensity of GFAP immunofluorescence. TH-2 h females also showed reduction of degenerative cells and morphological changes in astrocytes. Interestingly, females from the TH-6 h group showed an increase in volume of lesion and in number of degenerative hippocampal cells, associated with worse behavioral performance. Together, these results indicate that TH neuroprotection is time- and sex-dependent. Moreover, TH started later (6 h) can worsen volume of brain lesion in females. These data indicate the need to develop specific therapeutic protocols for each sex and reinforce the importance of early onset of the hypothermic treatment.


Assuntos
Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Animais , Masculino , Feminino , Ratos , Hipóxia-Isquemia Encefálica/terapia , Hipóxia-Isquemia Encefálica/patologia , Gliose/terapia , Gliose/patologia , Ratos Wistar , Animais Recém-Nascidos , Encéfalo , Isquemia/patologia , Isquemia/terapia , Modelos Animais de Doenças
9.
J Neurochem ; 157(6): 1911-1929, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33098090

RESUMO

Prenatal and early postnatal periods are important for brain development and neural function. Neonatal insults such as hypoxia-ischemia (HI) causes prolonged neural and metabolic dysregulation, affecting central nervous system maturation. There is evidence that brain hypometabolism could increase the risk of adult-onset neurodegenerative diseases. However, the impact of non-pharmacologic strategies to attenuate HI-induced brain glucose dysfunction is still underexplored. This study investigated the long-term effects of early environmental enrichment in metabolic, cell, and functional responses after neonatal HI. Thereby, male Wistar rats were divided according to surgical procedure, sham, and HI (performed at postnatal day 3), and the allocation to standard (SC) or enriched condition (EC) during gestation and lactation periods. In-vivo cerebral metabolism was assessed by means of [18 F]-FDG micro-positron emission tomography, and cognitive, biochemical, and histological analyses were performed in adulthood. Our findings reveal that HI causes a reduction in glucose metabolism and glucose transporter levels as well as hyposynchronicity in metabolic brain networks. However, EC during prenatal or early postnatal period attenuated these metabolic disturbances. A positive correlation was observed between [18 F]-FDG values and volume ratios in adulthood, indicating that preserved tissue by EC is metabolically active. EC promotes better cognitive scores, as well as down-regulation of amyloid precursor protein in the parietal cortex and hippocampus of HI animals. Furthermore, growth-associated protein 43 was up-regulated in the cortex of EC animals. Altogether, results presented support that EC during gestation and lactation period can reduce HI-induced impairments that may contribute to functional decline and progressive late neurodegeneration.


Assuntos
Encéfalo/metabolismo , Meio Ambiente , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/prevenção & controle , Plasticidade Neuronal/fisiologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Animais Recém-Nascidos , Feminino , Hipóxia-Isquemia Encefálica/psicologia , Lactação/metabolismo , Lactação/psicologia , Masculino , Aprendizagem em Labirinto/fisiologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/prevenção & controle , Doenças Neurodegenerativas/psicologia , Tomografia por Emissão de Pósitrons/métodos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/psicologia , Ratos , Ratos Wistar
10.
Neurochem Res ; 43(12): 2268-2276, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30255215

RESUMO

Neonatal hypoxia-ischemia (HI) is associated to cognitive and motor impairments and until the moment there is no proven treatment. The underlying neuroprotective mechanisms of stem cells are partially understood and include decrease in excitotoxicity, apoptosis and inflammation suppression. This study was conducted in order to test the effects of intracardiac transplantation of human dental pulp stem cells (hDPSCs) for treating HI damage. Seven-day-old Wistar rats were divided into four groups: sham-saline, sham-hDPSCs, HI-saline, and HI-hDPSCs. Motor and cognitive tasks were performed from postnatal day 30. HI-induced cognitive deficits in the novel-object recognition test and in spatial reference memory impairment which were prevented by hDPSCs. No motor impairments were observed in HI animals. Immunofluorescence analysis showed human-positive nuclei in hDPSC-treated animals closely associated with anti-GFAP staining in the lesion scar tissue, suggesting that these cells were able to migrate to the injury site and could be providing support to CNS cells. Our study evidence novel evidence that hDPSC can contribute to the recovery following hypoxia-ischemia and highlight the need of further investigation in order to better understand the exact mechanisms underlying its neuroprotective effects.


Assuntos
Disfunção Cognitiva/prevenção & controle , Polpa Dentária/transplante , Hipóxia-Isquemia Encefálica/terapia , Transplante de Células-Tronco/métodos , Animais , Animais Recém-Nascidos , Células Cultivadas , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Polpa Dentária/citologia , Polpa Dentária/fisiologia , Feminino , Ventrículos do Coração , Humanos , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/patologia , Injeções , Masculino , Aprendizagem em Labirinto/fisiologia , Gravidez , Distribuição Aleatória , Ratos , Ratos Wistar , Células-Tronco/fisiologia
11.
Metab Brain Dis ; 33(3): 813-821, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29363039

RESUMO

Progesterone displays a strong potential for the treatment of neonatal hypoxic-ischemic encephalopathy since it has been shown to be beneficial in the treatment of the central nervous system injuries in adult animals. Here, we evaluated the effects of the administration of progesterone (10 mg/kg) in seven-days-old male Wistar rats submitted to neonatal hypoxia-ischemia (HI). Progesterone was administered immediately before ischemia and/or 6 and 24 h after the onset of hypoxia. The body weight of the animals, the volume of brain lesion and the expression of p-Akt and procaspase-3 in the hippocampus were evaluated. All animals submitted to HI showed a reduction in the body weight. However, this reduction was more remarkable in those animals which received progesterone before surgery. Administration of progesterone was unable to reduce the volume of brain damage caused by HI. Moreover, no significant differences were observed in the expression of p-Akt and procaspase-3 in animals submitted to HI and treated with either progesterone or vehicle. In summary, progesterone did not show a neuroprotective effect on the volume of brain lesion in neonatal rats submitted to hypoxia-ischemia. Furthermore, progesterone was unable to modulate p-Akt and procaspase-3 signaling pathways, which may explain the absence of neuroprotection. On the other hand, it seems that administration of progesterone before ischemia exerts some systemic effect, leading to a remarkable reduction in the body weight.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Progesterona/farmacologia , Animais , Animais Recém-Nascidos , Peso Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Lesões Encefálicas/metabolismo , Caspase 3/metabolismo , Masculino , Fármacos Neuroprotetores/farmacologia , Progesterona/metabolismo , Ratos Wistar
12.
J Perinat Med ; 46(4): 433-439, 2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28841577

RESUMO

Neonatal hypoxia ischemia (HI) is the main cause of mortality and morbidity in newborns. The mechanisms involved in its progression start immediately and persist for several days. Oxidative stress and inflammation are determinant factors of the severity of the final lesion. The spleen plays a major part in the inflammatory response to HI. This study assessed the temporal progression of HI-induced alterations in oxidative stress parameters in the hippocampus, the most affected brain structure, and in the spleen. HI was induced in Wistar rat pups in post-natal day 7. Production of reactive oxygen species (ROS), and the activity of the anti oxidant enzyme superoxide dismutase and catalase were assessed 24 h, 96 h and 38 days post-HI. Interestingly, both structures showed a similar pattern, with few alterations in the production of ROS species up to 96 h often combined with an increased activity of the anti oxidant enzymes. However, 38 days after the injury, ROS were at the highest in both structures, coupled with a decrease in the activity of the enzymes. Altogether, present results suggest that HI causes long lasting alterations in the hippocampus as well as in the spleen, suggesting a possible target for delayed treatments for HI.


Assuntos
Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Estresse Oxidativo , Baço/metabolismo , Animais , Animais Recém-Nascidos , Catalase/metabolismo , Modelos Animais de Doenças , Feminino , Hipocampo/patologia , Hipóxia-Isquemia Encefálica/patologia , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Baço/patologia , Superóxido Dismutase/metabolismo
13.
J Neurosci Res ; 95(1-2): 409-421, 2017 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-27870406

RESUMO

Neonatal hypoxia-ischemia (HI) is an important cause of neurological deficits in humans, and the Levine-Rice model of experimental HI in the rat mimics the human brain lesion and the following sensory motor deficits and cognitive disabilities. With the growing evidence that sex influences all levels of brain functions, this Mini-Review highlights studies in which sex was a controlled variable and that provided evidence of sexual dimorphism in behavioral outcome, extension of brain damage, mechanisms of lesion, and treatment efficacy in the rat neonatal HI model. It was shown that 1) females have greater memory deficits; 2) cell death is dependent mainly on caspase activation in females; 3) males are more susceptible to oxidative stress; and 4) treatments acting on distinct cell death pathways afford sex-dependent neuroprotection. These tentative conclusions, along with growing evidence from other fields of neurobiology, support the need for scientists to design their experiments considering sex as an important variable; otherwise, important knowledge will continue to be missed. It is conceivable that sex can influence the development of efficacious therapeutic tools to treat neonates suffering from brain HI. © 2016 Wiley Periodicals, Inc.


Assuntos
Encéfalo/patologia , Deficiências do Desenvolvimento/etiologia , Hipóxia-Isquemia Encefálica/complicações , Caracteres Sexuais , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Hipóxia-Isquemia Encefálica/patologia , Hipóxia-Isquemia Encefálica/fisiopatologia , Masculino , Ratos
14.
Neurochem Res ; 42(5): 1422-1429, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28210957

RESUMO

Regular physical activity has shown to improve the quality of life and to prevent age-related memory deficits. Memory processing requires proper regulation of several enzymes such as sodium-potassium adenosine triphosphatase (Na+, K+-ATPase) and acetylcholinesterase (AChE), which have a pivotal role in neuronal transmission. The present study investigated the effects of a treadmill running protocol in young (3 months), mature (6 months) and aged (22 months) Wistar rats, on: (a) cognitive function, as assessed in the Water maze spatial tasks; (b) Na+, K+-ATPase and AChE activities in the hippocampus following cognitive training alone or treadmill running combined with cognitive training. Animals of all ages were assigned to naïve (with no behavioral or exercise training), sedentary (non-exercised, with cognitive training) and exercised (20 min of daily running sessions, 3 times per week for 4 weeks and with cognitive training) groups. Cognition was assessed by reference and working memory tasks run in the Morris Water maze; 24 h after last session of behavioral testing, hippocampi were collected for biochemical analysis. Results demonstrated that: (a) a moderate treadmill running exercise prevented spatial learning and memory deficits in aged rats; (b) training in the Water maze increased both Na+, K+-ATPase and AChE activities in the hippocampus of mature and aged rats; (c) aged exercised rats displayed an even further increase of Na+, K+-ATPase activity in the hippocampus, (d) enzyme activity correlated with memory performance in aged rats. It is suggested that exercise prevents spatial memory deficits in aged rats probably through the activation of Na+, K+-ATPase in the hippocampus.


Assuntos
Envelhecimento/metabolismo , Hipocampo/enzimologia , Transtornos da Memória/enzimologia , Condicionamento Físico Animal/fisiologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Memória Espacial/fisiologia , Animais , Ativação Enzimática/fisiologia , Teste de Esforço/métodos , Teste de Esforço/psicologia , Masculino , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/prevenção & controle , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/psicologia , Distribuição Aleatória , Ratos , Ratos Wistar
15.
Pediatr Res ; 82(3): 544-553, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28426648

RESUMO

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.


Assuntos
Hipóxia-Isquemia Encefálica/prevenção & controle , Neuroproteção , Natação , Animais , Comportamento Animal , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Feminino , Hipocampo/metabolismo , Lobo Parietal/enzimologia , Gravidez , Ratos , Ratos Wistar , Reflexo , ATPase Trocadora de Sódio-Potássio/metabolismo
16.
Exp Neurol ; 381: 114929, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39168170

RESUMO

Neonatal hypoxia-ischemia (HI) is one of the main causes of mortality and long-term disabilities in newborns, and the only clinical approach to treat this condition is therapeutic hypothermia, which shows some limitations. Thus, putative neuroprotective agents have been tested in animal models of HI. Lactate is a preferential metabolic substrate of the neonatal brain and has already been shown to produce beneficial neuroprotective outcomes in neonatal animals exposed to HI. Here, we administered lactate as a treatment in neonatal rats previously exposed to HI and evaluated the impact of this treatment in adulthood. Seven-day-old (P7) male and female Wistar rats underwent permanent common right carotid occlusion combined with an exposition to a hypoxic atmosphere (8% oxygen) for 60 min. Animals were assigned to one of four experimental groups: HI, HI+LAC, SHAM, SHAM+LAC. Lactate was administered intraperitoneally 30 min and 2 h after hypoxia in HI+LAC and SHAM+LAC groups, whereas HI and SHAM groups received vehicle. Animals were tested in the behavioral tasks of negative geotaxis and righting reflex (P8), cylinder test (P24), and the modified neurological severity score was calculated (P25). Open field (OF), and novel object recognition (NOR) were evaluated in adulthood. Animals were killed at P60, and the brains were harvested and processed to evaluate the volume of brain injury. Our results showed that lactate administration reduced the volume of brain lesion and improved sensorimotor and cognitive behaviors in neonatal, juvenile, and adult life in HI animals from both sexes. Thus, lactate administration might be considered as a potential neuroprotective strategy for the treatment of neonatal HI, which is a prevalent disorder affecting newborns.

17.
Sci Total Environ ; 946: 174173, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38925398

RESUMO

Elements that interfere with reproductive processes can have profound impacts on population and the equilibrium of ecosystems. Global warming represents the major environmental challenge of the 21st century, as it will affect all forms of life in the coming decades. Another coexisting concern is the persistent pollution by pesticides, particularly the herbicide Atrazine (ATZ), which is responsible for a significant number of contamination incidents in surface waters worldwide. While it is hypothesized that climate changes will significantly enhance the toxic effects of pesticides, the actual impact of these phenomena remain largely unexplored. Here, we conducted a climate-controlled room experiment to assess the interactive effects of the projected 2100 climate scenario and environmentally realistic ATZ exposures on the reproductive function of male zebrafish. The gonadosomatic index significantly decreased in fish kept in the extreme scenario. Cellular alterations across spermatogenesis phases led to synergic decreased sperm production and increased germ cell sloughing and death. ATZ exposure alone or combined with climate change effects, disrupted the transcription levels of key genes involved in steroidogenesis, hormone signaling and spermatogenesis regulation. An additive modulation with decreased 11-KT production and increased E2 levels was also evidenced, intensifying the effects of androgen/estrogen imbalance. Moreover, climate change and ATZ independently induced oxidative stress, upregulation of proapoptotic gene and DNA damage in post-meiotic germ cell, but the negative effects of ATZ were greater at extreme scenario. Ultimately, exposure to simulated climate changes severely impaired fertilization capacity, due to a drastic reduction in sperm motility and/or viability. These findings indicate that the future climate conditions have the potential to considerably enhance the toxicity of ATZ at low concentrations, leading to significant deleterious consequences for fish reproductive function and fertility. These may provide relevant information to supporting healthcare and environmental managers in decision-making related to climate changes and herbicide regulation.


Assuntos
Atrazina , Mudança Climática , Herbicidas , Testículo , Poluentes Químicos da Água , Peixe-Zebra , Animais , Atrazina/toxicidade , Peixe-Zebra/fisiologia , Masculino , Poluentes Químicos da Água/toxicidade , Testículo/efeitos dos fármacos , Herbicidas/toxicidade , Espermatogênese/efeitos dos fármacos , Reprodução/efeitos dos fármacos
18.
An Acad Bras Cienc ; 85(3): 1083-1091, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23969847

RESUMO

This study aimed to develop a protocol of semen cryopreservation of the mutton snapper Lutjanus analis. The interaction between three extenders ( pH 6.1; 7.8 and 8.2) , two concentrations of dimethyl sulfoxide ( DMSO, 5 and 10%) and three cooling rates ( -90; -60 and -30°C.min-1) on the sperm motility rate and motility time were analyzed by a factorial experiment. A sample of 30 fishes ( 1,261 ± 449 g) collected in the nature was kept in floating net cages. The semen was frozen by using cryogenic straws, in nitrogen vapour and transferred, later, to liquid nitrogen. Fertilization test was accomplished to evaluate the viability of the cryopreserved sperm. The highest sperm motility rate and motility time ( P < 0.05) was achieved by combining extender C ( pH 8.2) with DMSO ( 10%) and cooling rate of -60°C.min-1 ( P < 0.05) . The use of cryopreserved sperm presented fertilization rates higher than 59% validating the present protocol for mutton snapper.


Assuntos
Criopreservação/veterinária , Perciformes , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides/fisiologia , Animais , Criopreservação/métodos , Masculino , Preservação do Sêmen/métodos , Fatores de Tempo
19.
Carbohydr Polym ; 320: 121214, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659814

RESUMO

Mucopolysaccharidosis IIIA is a hereditary disease caused by mutations in the sulfamidase enzyme that participates in catabolism of heparan sulfate (HS), leading to HS fragment accumulation and multisystemic failure. No cure exists and death occurs around the second decade of life. Two low molecular weight highly sulfated compounds derived from marine diabolican and infernan exopolysaccharides (A5_3 and A5_4, respectively) with heparanase inhibiting properties were tested in a MPSIIIA cell line model, resulting in limited degradation of intracellular HS. Next, we observed the effects of intraperitoneal injections of the diabolican derivative A5_3 from 4 to 12 weeks of age on MPSIIIA mice. Brain metabolism and microstructure, levels of proteins and genes involved in MPSIIIA brain pathophysiology were also investigated. 1H-Magnetic Resonance Spectroscopy (MRS) indicated deficits in energetic metabolism, tissue integrity and neurotransmission at both 4 and 12 weeks in MPSIIIA mice, with partial protective effects of A5_3. Ex-vivo Diffusion Tensor Imaging (DTI) showed white matter microstructural damage in MPSIIIA, with noticeable protective effects of A5_3. Protein and gene expression assessments displayed both pro-inflammatory and pro-apoptotic profiles in MPSIIIA mice, with benefits of A5_3 counteracting neuroinflammation. Overall, derivative A5_3 was well tolerated and was shown to be efficient in preventing brain metabolism failure and inflammation, resulting in preserved brain microstructure in the context of MPSIIIA.

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