RESUMO
Objective: To study the association of health-related physical fitness (HPF) with kidney function and blood lipid to provide a basis to prevent chronic diseases and making exercise prescriptions. Methods: This study was conducted in December 2019 with 299 faculty members of a university in Shaanxi, testing HPF indicators (muscle mass, body fat percentage, grip, sit-and-reach, vital capacity) , kidney function indicators (creatinine, uric acid, urea) , and blood lipid indicators[triglyceride (TG) , total cholesterol (TC) , high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) ]. Spearman correlation analysis and binary logistic regression were used to analyze the association between HPF with kidney function and blood lipid indicators. Results: In men, muscle mass and grip strength were positively correlated with uric acid, body fat percentage was positively correlated with TG, sit-and-reach and vital capacity were negatively correlated with TG (r(s)=0.266, 0.337, 0.300, -0.339, -0.239, P<0.05) . In women, body fat percentage was positively correlated with uric acid, TG, TC and LDL-C, negatively correlated with creatinine and HDL-C, grip strength was positively correlated with creatinine, sit-and-reach was positively correlated with HDL-C and negatively correlated with TG, vital capacity was negatively correlated with urea (r(s)=0.240, 0.349, 0.214, 0.249, -0.254, -0.209, 0.186, 0.207, -0.255, -0.154, P<0.05) . Logistic regression showed that high body fat percentage was risk factor for abnormal uric acid and dyslipidemia in female faculty members (OR=1.114, 95%CI:1.023-1.213; OR=1.116, 95%CI: 1.034-1.208; P<0.05) . And high body fat percentage was risk factor for dyslipidemia in male faculty members (OR=1.129, 95%CI: 1.017-1.252, P<0.05) . Conclusion: High body fat percentage is associated with dyslipidemia and uric acid abnormalities in university faculty. HPF fitness assessment may be important for the prevention of chronic diseases related to kidney function or lipids.
Assuntos
Lipídeos , Universidades , Docentes , Feminino , Humanos , Rim , Masculino , Aptidão FísicaRESUMO
Social interaction is a fundamental behavior in all animal species, but the developmental timing of the social neural circuit formation and the cellular and molecular mechanisms governing its formation are poorly understood. We generated a mouse model with mutations in two Disheveled genes, Dvl1 and Dvl3, that displays adult social and repetitive behavioral abnormalities associated with transient embryonic brain enlargement during deep layer cortical neuron formation. These phenotypes were mediated by the embryonic expansion of basal neural progenitor cells (NPCs) via deregulation of a ß-catenin/Brn2/Tbr2 transcriptional cascade. Transient pharmacological activation of the canonical Wnt pathway during this period of early corticogenesis rescued the ß-catenin/Brn2/Tbr2 transcriptional cascade and the embryonic brain phenotypes. Remarkably, this embryonic treatment prevented adult behavioral deficits and partially rescued abnormal brain structure in Dvl mutant mice. Our findings define a mechanism that links fetal brain development and adult behavior, demonstrating a fetal origin for social and repetitive behavior deficits seen in disorders such as autism.
Assuntos
Transtorno de Movimento Estereotipado/genética , Transtorno de Movimento Estereotipado/fisiopatologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Comportamento Animal , Encéfalo/embriologia , Encéfalo/metabolismo , Encéfalo/fisiologia , Proteínas Desgrenhadas/genética , Proteínas Desgrenhadas/metabolismo , Humanos , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/fisiologia , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Fatores do Domínio POU/metabolismo , Fatores do Domínio POU/fisiologia , Fosfoproteínas/genética , Transdução de Sinais/fisiologia , Comportamento Estereotipado/fisiologia , Proteínas com Domínio T/metabolismo , Proteínas com Domínio T/fisiologia , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , beta Catenina/fisiologiaRESUMO
Life-history characteristics of age-0 sturgeon chub Macrhybopsis gelida, shoal chub Macrhybopsis hyostoma and sicklefin chub Macrhybopsis meeki were compared using several methods. All Macrhybopsis species consumed mostly midge pupae, but M. meeki had the most general diet (Levins' index, B = 0.22) compared with M. hyostoma (B = 0.02) and M. gelida (B = 0.09). Morisita's diet overlap index among species pairs ranged from 0.62 to 0.97 and was highest between M. hyostoma and M. gelida. Daily ages estimated from lapilli otoliths for each species ranged from 15 to 43 days for M. gelida, 19 to 44 for M. hyostoma and from 16 to 64 days for M. meeki. Mean growth rates ranged from 0.79 mm day(-1) for M. meeki to 1.39 mm day(-1) for M. gelida. Mortality estimates indicated high daily survivorship rates for M. meeki (0.985), but could not be estimated for the other two species. Hatch date histograms were congruent with the belief that M. hyostoma and M. gelida spawn periodically from June to September. Macrhybopsis meeki, however, appeared to respond to a specific spawning cue as hatch dates were unimodal with a peak in July. These results fill a gap in current knowledge of these imperilled species that can be used to guide management decisions.
Assuntos
Cyprinidae/fisiologia , Estágios do Ciclo de Vida , Animais , Cyprinidae/crescimento & desenvolvimento , Dieta/veterinária , Missouri , Membrana dos Otólitos/crescimento & desenvolvimento , Reprodução , RiosRESUMO
Dengue fever is an acute mosquito-borne infectious disease caused by dengue virus and widely spread worldwide. Many factors, such as pathogens, vector organisms, climate, and social environment, affect its transmission and prevalence. The local dengue fever epidemic caused by imported cases in China shows a trend of increasing epidemic latitude and more widespread epidemic areas. However, the traditional monitoring and early warning models of dengue fever mainly focus on researching a single factor and a single area. Establishing a multi-factor forecast and early warning system is urgent to strengthen the early warning capability for the dengue fever epidemic. This paper mainly discusses the epidemic characteristics, the influencing factors, and the surveillance and early warning models of dengue fever in China to provide a reference for the effective prevention and control of dengue fever in China.
Assuntos
Dengue , Epidemias , Animais , Humanos , Dengue/epidemiologia , Surtos de Doenças/prevenção & controle , Clima , China/epidemiologiaRESUMO
Maternal nutrient restriction during pregnancy alters fetal programming, which modifies the growth and health of the offspring in postnatal life. In cattle, nutrient restriction during pregnancy can be a result of environmental or economic factors, but little is known about how it alters the physiology of the fetus and affects future reproductive or growth efficiency. This study used female monozygotic twins, produced through in vitro fertilization and embryo splitting, to determine the effect of moderate maternal nutrient restriction on fetal development. Recipient Angus cross heifers pregnant with one twin were fed a diet meeting 100% National Research Council (NRC) total energy requirements (n = 4; control), whereas recipient heifers pregnant with the second twin were fed at 70% of NRC total energy requirements (n = 4; restricted) from gestational day (GD) 158 to GD 265 in Calan gate feeders. Recipient heifers were killed at GD 265. Change in maternal metabolic body weight was greater from zero in restricted heifers than controls (P < 0.05); restricted heifers lost weight during the nutrient restriction period. There was no difference in last rib back fat or rib eye area between groups (P > 0.10). There was no difference in fetal weight, uterine weight, or total placentome weight between groups (P > 0.10). The pancreas weight was reduced in restricted fetuses compared with control fetuses (P < 0.01), but there were no other differences in fetal organ weights (P > 0.10). Plasma insulin concentrations were reduced in restricted fetuses compared with controls (P < 0.01), but there was no effect of maternal diet on plasma glucose or glucagon concentrations in the fetus (P > 0.10). Histological analyses of the fetal pancreas revealed no differences in endocrine cell number or localization. Results indicate that a modest late gestation nutritional restriction impairs development of the fetal pancreas in the cow. Additional research will be needed to determine if these developmental changes lead to altered glucose and insulin homeostasis in the adult.
Assuntos
Ração Animal/análise , Bovinos/embriologia , Dieta/veterinária , Insulina/metabolismo , Pâncreas/embriologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Técnicas de Cultura Embrionária , Transferência Embrionária , Feminino , Desenvolvimento Fetal , Privação de Alimentos , Pâncreas/metabolismo , Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal , Gemelaridade MonozigóticaRESUMO
Campylobacter is regarded as a leading cause of human bacterial gastroenteritis in the United States. We report on a case of laboratory-confirmed Campylobacter jejuni infection in the Commonwealth of Pennsylvania among members of a household living with a laboratory-confirmed but non-speciated Campylobacter-infected puppy. We describe an outbreak of likely dog-associated campylobacteriosis, the risk factors, potential routes of exposure and the clinical features in the exposed family members, which began shortly after exposure to the recently purchased dog. We also provide public health recommendations to prevent Campylobacter infections in veterinary care providers, pet owners and those planning to adopt pets in the future. Finally, this report underscores the importance of the One Health approach when public health responders, human and animal healthcare providers and clinical diagnostic laboratories are tasked with developing effective strategies when investigating, detecting and responding to zoonoses (diseases shared between animals and humans).
Assuntos
Infecções por Campylobacter/veterinária , Campylobacter jejuni/isolamento & purificação , Doenças do Cão/microbiologia , Animais de Estimação/microbiologia , Zoonoses , Adolescente , Adulto , Animais , Antibacterianos/uso terapêutico , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/transmissão , Pré-Escolar , Doenças do Cão/tratamento farmacológico , Cães , Eritromicina/uso terapêutico , Fezes/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Única , Fatores de RiscoRESUMO
Objective: To analyze the relationship between family-related factors and the status of overweight and obesity in children and adolescents aged 6-17 years in China. Methods: Data were collected from the China National Nutrition and Health Surveillance in 2010-2012 program. A sample of 6 343 subjects aged 6-17 years was selected, with matched weight, education levels, household income and other family related factors of their parents. Univariate analysis and multivariate logistic regression were used to explore the relationship between family factors and overweight and obesity in school-aged children and adolescents. Results: After adjusted for age, gender and region, results from the multivariate logistic regression showed that both the overweight and obesity of children and adolescents were associated with maternal BMI (OR=1.83, 95%CI: 1.63-2.05), paternal BMI (OR=1.74, 95%CI: 1.57-1.94), mother's educational level (OR=1.24, 95%CI: 1.12-1.37) and household income (OR=1.30, 95%CI: 1.15-1.46). Conclusion: Factors as overweight or obesity status of the parents, mother's educational level and household income were positively correlated with the prevalence of overweight and obesity in Chinese children and adolescents.
Assuntos
Família/psicologia , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Adolescente , Índice de Massa Corporal , Peso Corporal , Criança , China/epidemiologia , Estudos Transversais , Características da Família , Feminino , Humanos , Masculino , Obesidade/etnologia , Obesidade/psicologia , Sobrepeso/psicologia , Relações Pais-Filho , Pais , Obesidade Infantil/epidemiologia , Obesidade Infantil/etnologia , Prevalência , Instituições AcadêmicasRESUMO
We present a cross-cultural exploration of the interrelationships among six concepts: achievement (ie, cultural attainment), aggression, psychological distress, competition, interpersonal intensity (strength of passionate attachments), and social synergy (patterned behavior that simultaneously benefits both individual and society). Of interest is the proposition that levels of achievement, aggression, and psychological distress are partly determined by corresponding levels of competition and interpersonal intensity; however, in the presence of high levels of social synergy, aggression and psychological distress are lowered without affecting the level of achievement. We have tested the implied linear relationships, using blind ratings (of five variables assessed from ethnographic extracts) obtained from ten cross-cultural scholars, and a Social Development Index (from Tatje and Naroll) to indicate achievement. A sample of 58 societies was employed in correlation and multivariate analysis of variance.
Assuntos
Logro , Agressão/psicologia , Comparação Transcultural , Estresse Psicológico/psicologia , Comportamento Competitivo , Humanos , Relações Interpessoais , Apego ao ObjetoRESUMO
Dvl1 is one of three murine Dishevelled genes widely expressed in embryonic development and in the adult central nervous system. Dishevelled proteins are a necessary component of the Wnt and planar cell polarity developmental signaling pathways. We reported previously that mice deficient in Dvl1 exhibited abnormal social interaction and sensorimotor gating. To assess the validity of our earlier findings, we replicated the previous behavioral tests and included several new assays. The behaviors assessed included: social interaction, sensorimotor reflexes, motor activity, nociception, prepulse inhibition of acoustic startle (PPI) and learning and memory. Assessments with an explicit social component included: social dominance test, whisker trimming, nest building, home-cage huddling and ultrasonic vocalization rate analysis in pups. In addition, separate cohorts of wildtype and Dvl1-null mice were assessed for social recognition of a conspecific. Replicating the original report, Dvl1-null mice were impaired in several tasks containing an explicit social component. However, no impairment was observed in the social memory task. A previously observed deficit in PPI did not replicate in two institutions. In conclusion, we provide evidence that the social interaction phenotype of Dvl1-deficient mice has a strong genetic influence, but the sensorimotor gating deficit was subject to environmental influences. The specificity of observed social interaction deficits also suggests that lack of Dvl1 is associated with deficits in the recognition of social hierarchy and dominance.
Assuntos
Inibição Neural/genética , Fosfoproteínas/genética , Reflexo de Sobressalto/genética , Comportamento Social , Proteínas Adaptadoras de Transdução de Sinal , Animais , Comportamento Animal/fisiologia , Proteínas Desgrenhadas , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos , Camundongos Mutantes , Comportamento de Nidação/fisiologia , Fosfoproteínas/fisiologia , Desempenho Psicomotor/fisiologia , VibrissasRESUMO
Male C57BL/6J mice were provided I-deprenyl (at 0, 0.5 mg/kg or 1.0 mg/kg per day) in their drinking water beginning at 18 months of age. A battery of motor tests, including open-field, tightrope, rotorod, inclined screen, runwheel, and rotodrum tests, was administered before treatment and then 6 months later at 24 months of age. A subsample of mice was retested again at 27 months of age. An untreated group of 9-month-old mice served as young controls. Deprenyl treatment reduced striatal MAO-B activity by up to 60% after 6 months on treatment but had no significant effects on striatal catecholamine levels. No significant effects of deprenyl treatment were observed on body weight, fluid intake, or survival of the mice. Chronic deprenyl treatment also did not affect motor performance in any test, except rotodrum performance at 27 months of age, which was significantly better in the 1.0 mg/kg group treated group compared to controls. No age or deprenyl effects were observed with respect to cell counts in the substantia nigra. However, nigral cells containing lipofuscin increased with age, but this neurohistochemical parameter was also unaffected by deprenyl treatment.
Assuntos
Envelhecimento/efeitos dos fármacos , Corpo Estriado/enzimologia , Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/metabolismo , Desempenho Psicomotor/efeitos dos fármacos , Selegilina/farmacologia , Substância Negra/metabolismo , Envelhecimento/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Catecolaminas/metabolismo , Condicionamento Operante/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Ingestão de Líquidos/efeitos dos fármacos , Lipofuscina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Equilíbrio Postural/efeitos dos fármacos , Receptores Dopaminérgicos/efeitos dos fármacos , Receptores Dopaminérgicos/metabolismo , Substância Negra/citologia , Substância Negra/efeitos dos fármacosRESUMO
The 129 mouse strain has been widely used to construct mutations that model behavioral aging in humans. The current study found significant age-related declines in both psychomotor and swim maze performance of 5-, 17-, and 27-month-old 129/SvJ mice. However, the age differences in swim maze acquisition were inconsistent with poor performance in the probe trial which assesses spatial memory. This inconsistency may result from the high degree of genetic polymorphisms and age-related visual pathology which afflicts this mouse strain. Therefore, we concluded that 129/SvJ mice present a problematic model of mammalian cognitive aging and involve a risk for behavioral contamination in studies involving mutant mice derived from this strain.
Assuntos
Envelhecimento/psicologia , Aprendizagem/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Animais , Peso Corporal/fisiologia , Olho/crescimento & desenvolvimento , Olho/patologia , Manobra Psicológica , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos , Atividade Motora/fisiologia , Equilíbrio Postural/fisiologiaRESUMO
Recent evidence suggests neuroglia-mediated inflammatory mechanisms may stimulate neurodegenerative processes in mammalian brain during aging. To test the hypothesis that the number of microglia and astrocytes increase in the hippocampus during normal aging, unbiased stereological techniques were used to estimate total cell number in hippocampal subregions (CA1, dentate gyrus and hilus) of male C57BL/6J mice of different ages: 4-5 months, 13-14 months and 27-28 months. Immunocytochemical visualization for microglia and astrocytes were via Mac-1 and GFAP antibody, respectively. Estimates of total microglia and astrocyte number were assessed using the optical fractionator. No statistically significant age differences were found in the numbers of microglia or astrocytes in the hippocampal regions sampled. These findings suggest that age-related increases in the total numbers of hippocampal microglia and astrocytes is not causal for observed age-related increases in cytokine response.
Assuntos
Envelhecimento/fisiologia , Astrócitos/citologia , Giro Denteado/citologia , Microglia/citologia , Animais , Contagem de Células , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Análise de RegressãoRESUMO
A loss of hippocampal neurons and synapses had been considered a hallmark of normal aging and, furthermore, to be a substrate of age-related learning and memory deficits. Recent stereological studies in humans have shown that only a relatively minor neuron loss occurs with aging and that this loss is restricted to specific brain regions, including hippocampal subregions. Here, we investigate these age-related changes in C57BL/6J mice, one of the most commonly used laboratory mouse strains. Twenty-five mice (groups at 2, 14, and 28-31 months of age) were assessed for Morris water-maze performance, and modern stereological techniques were used to estimate total neuron and synaptophysin-positive bouton number in hippocampal subregions at the light microscopic level. Results revealed that performance in the water maze was largely maintained with aging. No age-related decline was observed in number of dentate gyrus granule cells or CA1 pyramidal cells. In addition, no age-related change in number of synaptophysin-positive boutons was observed in the molecular layer of the dentate gyrus or CA1 region of hippocampus. We observed a significant correlation between dentate gyrus synaptophysin-positive bouton number and water-maze performance. These results demonstrate that C57BL/6J mice do not exhibit major age-related deficits in spatial learning or hippocampal structure, providing a baseline for further study of mouse brain aging.
Assuntos
Envelhecimento/fisiologia , Cognição/fisiologia , Hipocampo/citologia , Neurônios/citologia , Sinapses/fisiologia , Animais , Hipocampo/fisiologia , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Sinaptofisina/metabolismo , Análise e Desempenho de TarefasRESUMO
Coronary arteriographic findings, plasma lipid and lipoprotein levels, and cigarette smoking history are reported for the first 101 male post myocardial infarction survivors who have been entered into the POSCH clinical trial. Estimates of the extent of stenosis in the major coronary arteries were made using 4 models ranging from a simple determination of the number of the 3 major vessels having significant (i.e. 50% or greater stenosis) disease to more complex methods of determining overall extent of disease in 14 major segments of the coronary arteries. Age was shown to be an important factor in the extent of vessel disease. When controlling for age, plasma cholesterol and LDL-cholesterol levels were shown to be related to the extent of disease, especially in Type II hyperlipoproteinemia subjects. Multiple linear regression analysis demonstrated that age and LDL-cholesterol had positive associations and HDL-cholesterol had an inverse association with the coronary artery disease indices. In this comparatively "healthy" subgroup of the overall population of first MI survivors the major CHD risk factors are limited to plasma lipids and cigarette smoking. This preliminary report of 10% of the recruitment objective of the project supports the currently held views of the lipid--atherosclerosis hypothesis regarding the effects of age-total plasma cholesterol, LDL--cholesterol, and HDL--cholesterol on the extent of coronary atherosclerotic plaques, as determined by coronary arteriography.
Assuntos
Doença das Coronárias/etiologia , Hiperlipidemias/complicações , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Triglicerídeos/sangue , Adulto , Angiografia , Colesterol/sangue , Ensaios Clínicos como Assunto , Angiografia Coronária , Doença das Coronárias/diagnóstico , Feminino , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/prevenção & controle , Íleo/cirurgia , Masculino , Pessoa de Meia-Idade , Minnesota , Programas Médicos Regionais , RiscoRESUMO
Hormone replacement therapy with the gonadal steroid estrogen or synthetic agents such as raloxifene, a selective estrogen receptor modulator, may affect cellular function in brains of postmenopausal women. In vitro studies suggest that 17beta estradiol and raloxifene can alter the microglial and astrocyte expression of immuno-neuronal modulators, such as cytokines, complement factors, chemokines, and other molecules involved in neuroinflammation and neurodegeneration. To directly test whether exogenous 17beta estradiol and raloxifene affect the number of glial cells in brain, C57BL/6NIA female mice aged 20-24 months received bilateral ovariectomy followed by s.c. placement of a 60-day release pellet containing 17beta estradiol (1.7 mg), raloxifene (10 mg), or placebo (cholesterol). After 60 days, numbers of microglia and astrocytes were quantified in dentate gyrus and CA1 regions of the hippocampal formation using immunocytochemistry and design-based stereology. The results show that long-term 17beta estradiol treatment in aged female mice significantly lowered the numbers of astrocytes and microglial cells in dentate gyrus and CA1 regions compared with placebo. After long-term treatment with raloxifene, a similar reduction was observed in numbers of astrocytes and microglial cells in the hippocampal formation. These findings indicate that estrogen and selective estrogen receptor modulators can influence glial-mediated inflammatory pathways and possibly protect against age- and disease-related neuropathology.
Assuntos
Envelhecimento/fisiologia , Antagonistas de Estrogênios/farmacologia , Estrogênios/farmacologia , Hipocampo/citologia , Neuroglia/efeitos dos fármacos , Cloridrato de Raloxifeno/farmacologia , Animais , Contagem de Células , Estrogênios/administração & dosagem , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Antígeno de Macrófago 1/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/citologia , Ovariectomia/métodos , Técnicas EstereotáxicasRESUMO
1. Characterization of the beta-adrenoceptors mediating inhibition of gastric acid secretion in the conscious Heidenhain pouch dog has been investigated by determination of the effects of propranolol, (+)-propranolol, practolol and H35/25 on salbutamol and isoprenaline-induced inhibition of gastric acid secretion. 2. The gastric antisecretory effect of salbutamol was significantly blocked by propranolol and H35/25 but not by practolol or (+)-propranolol. The effect of isoprenaline was significantly blocked by propranolol and practolol but not by H35/25 or (+)-propranolol. 3. It is concluded that both beta1- and beta2-adrenoceptors can mediate inhibition of pentagastrin-induced gastric secretion in conscious dogs with a Heidenhain pouch. Salbutamol exerts its antisecretory effect through beta2-adrenoceptors, whereas isoprenaline mediates its effects primarily through beta1-adrenoceptors. 4. The results are discussed with regard to the sub-classification of beta-adrenoceptors and to the possible role of adrenoceptors in the physiological control of gastric secretion. 5. In this study it is concluded that the tachycardia induced by isoprenaline or salbutamol is mediated primarily through reflexes activated by beta2-adrenoceptor mediated vasodilatation.
Assuntos
Suco Gástrico/metabolismo , Receptores Adrenérgicos beta/fisiologia , Receptores Adrenérgicos/fisiologia , Albuterol/farmacologia , Animais , Cães , Frequência Cardíaca/efeitos dos fármacos , Isoproterenol/farmacologia , Masculino , Pentagastrina/farmacologia , Propranolol/farmacologia , Receptores Adrenérgicos beta/efeitos dos fármacosRESUMO
To identify genetic factors involved in brain aging, we have initiated studies assessing behavioral and structural changes with aging among inbred mouse strains. Cognitive performance of C57BL/6J mice is largely maintained with aging, and stereological analysis revealed no significant age-related change in neuron number, synaptic bouton number or glial number in the hippocampus. Moreover, no change in cortical neuron number and cholinergic basal forebrain neuron number has been found in this strain. 129Sv/J mice have more pronounced age-related cognitive deficits, although hippocampal and basal cholinergic forebrain neuron number also appear unchanged with aging. Differences in neurogenesis and neuron vulnerability in the adult CNS of C57BL/6, 129/Sv and other inbred strains have been reported, which in turn may have important consequences for brain aging. Age-related lesions, such as thalamic eosinophilic inclusions and hippocampal clusters of polyglucosan bodies also vary greatly among inbred strains although the functional significance of these lesions is not clear. The continued assessment of such age-related structural and behavioral changes among inbred mouse strains offers the potential to identify genes that control age-related changes in brain structure and function.
Assuntos
Envelhecimento , Encéfalo/patologia , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Endogâmicos , Camundongos Transgênicos , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologiaRESUMO
The adult brain contains neural stem cells that are capable of proliferating, differentiating into neurons or glia, and then either surviving or dying. This process of neural-cell production (neurogenesis) in the dentate gyrus of the hippocampus is responsive to brain injury, and both mental and physical activity. We now report that neurogenesis in the dentate gyrus can also be modified by diet. Previous studies have shown that dietary restriction (DR) can suppress age-related deficits in learning and memory, and can increase resistance of neurons to degeneration in experimental models of neurodegenerative disorders. We found that maintenance of adult rats on a DR regimen results in a significant increase in the numbers of newly produced neural cells in the dentate gyrus of the hippocampus, as determined by stereologic analysis of cells labeled with the DNA precursor analog bromodeoxyuridine. The increase in neurogenesis in rats maintained on DR appears to result from decreased death of newly produced cells, rather than from increased cell proliferation. We further show that the expression of brain-derived neurotrophic factor, a trophic factor recently associated with neurogenesis, is increased in hippocampal cells of rats maintained on DR. Our data are the first evidence that diet can affect the process of neurogenesis, as well as the first evidence that diet can affect neurotrophic factor production. These findings provide insight into the mechanisms whereby diet impacts on brain plasticity, aging and neurodegenerative disorders.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Giro Denteado/citologia , Giro Denteado/fisiologia , Privação de Alimentos , Regulação da Expressão Gênica/fisiologia , Neurônios/citologia , Animais , Fator Neurotrófico Derivado do Encéfalo/análise , Bromodesoxiuridina , Divisão Celular , Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Ingestão de Energia , Hipocampo/citologia , Hipocampo/fisiologia , Hibridização In Situ , Masculino , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Transcrição GênicaRESUMO
Long-term memory formation requires de novo RNA and protein synthesis. To assess gene-expression changes associated with learning and memory processes, we used cDNA microarray to analyze hippocampal gene expression in male Fischer-344 rats following training in a multiunit T-maze. Here, we report the identification of 28 clones (18 known genes and 10 ESTs) for which expression increased after the maze learning. Some of the known genes appear to be involved in Ca2+ signaling, Ras activation, kinase cascades, and extracellular matrix (ECM) function, which may regulate neural transmission, synaptic plasticity, and neurogenesis. The gene-expression profile presented here provides the groundwork for future, more focused research to elucidate the contribution of these genes in learning and memory processes.
Assuntos
Hipocampo/metabolismo , Aprendizagem em Labirinto , Análise de Sequência com Séries de Oligonucleotídeos , Animais , Expressão Gênica , Hipocampo/fisiologia , Masculino , Memória , Ratos , Ratos Endogâmicos F344 , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
To test for the contribution of the parietal cortex and hippocampus to memory for allocentric spatial cues, the authors trained rats on a go/no-go task that required the rat to remember the distance between two visual cues. Total hippocampal lesions impaired working-memory representation for allocentric distance, whereas parietal cortex lesions resulted in only a transient impairment. In a second experiment, neither hippocampal nor parietal cortex lesions impaired allocentric distance discrimination. A third experiment showed that both the dorsal and ventral areas of the hippocampal formation must be destroyed to impair working memory for allocentric distance information. There appears to be a dissociation between the hippocampus and parietal cortex in mediating memory for allocentric distance information.