RESUMO
Microcirculation has great importance in eye and testicular tissue and is necessary to have adequate and appropriate amount of angiogenesis. It is known that high levels of Vascular Endothelial Growth Factor (VEGF) trigger uncontrolled angiogenesis, whereas inadequate VEGF can lead to decreased tissue perfusion and oxygenation. The aim of this study was to investigate effects of VEGF in testicular and ocular tissues in both non-diabetic and diabetic rats treated by statin. Atorvastatin (10â¯mg/kg daily given by orally gavage) was administered for two weeks. Diabetes was induced by streptozotocin, (STZ, 45â¯mg/kg/ip) in diabetic group's rats. Two weeks later from STZ injection, atorvastatin treatment was initiated in diabetic group. VEGF levels were measured by using ELISA. The VEGF levels were decreased in vitrous, ocular and testicular tissues of all statin-administered rats. In diabetic group VEGF levels were found to be decreased in testicular tissue and increased in ocular tissues. CONCLUSION: Statin use decreased in VEGF levels of testicular and ocular tissues in diabetic and non-diabetic rats. Statin treatment (anti-VEGF effect) had a protective effect in the development of diabetic retinopathy, yet statins may have a negative impact on tissues that depend on microcirculation by reducing VEGF levels. Further research is needed for statins' microcellular effects.
Assuntos
Inibidores da Angiogênese/farmacologia , Atorvastatina/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/prevenção & controle , Olho/irrigação sanguínea , Olho/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Microcirculação/efeitos dos fármacos , Testículo/irrigação sanguínea , Testículo/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/etiologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/fisiopatologia , Regulação para Baixo , Olho/metabolismo , Masculino , Neovascularização Patológica , Ratos Wistar , Testículo/metabolismoRESUMO
Acetaminophen (APAP) is widely used in the treatment of pain. Toxic doses of APAP cause acute liver failure, but therapeutic doses are believed to be safe. The purpose of this study is to investigate the effects of administration of subtoxic doses of APAP on liver and blood levels of insulin-like growth factor-1 (IGF-1) in rats. Low dose (100 mg/kg) and high dose (250 mg/kg) of APAP were intraperitoneally injected into Wistar albino rats. Following administration of therapeutic doses of APAP, there were no significant changes in serum transaminases and liver glutathione levels. Both doses of APAP induced a decrease in liver and blood levels of IGF-1 when compared with the controls. There was no significant difference in liver IGF-1 levels between the high-dose and low-dose APAP groups; however, there was a significant difference in blood IGF-1 levels between both the groups. The histological examination showed that low dose of APAP induced mild degree of structural change, while high dose of APAP induced severe structural damage. In conclusion, these results suggest that blood IGF-1 levels may have a value in predicting hepatic damage resulting from therapeutic doses of APAP.
Assuntos
Acetaminofen/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/efeitos dos fármacos , Acetaminofen/administração & dosagem , Animais , Antioxidantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Fígado/metabolismo , Masculino , Ratos , Ratos WistarRESUMO
BACKGROUND: Because brain development continues during adolescence, the effects of chronic stress on hippocampal changes that occur during that period are permanent. Oxytocin, which is synthesized in the hypothalamus and has many receptors in brain regions, including the hippocampus, may affect learning-memory. This study aimed to investigate chronic restraint stress on hippocampal functions, and hippocampal vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF) levels in adolescent male and female rats and the role of oxytocin in these effects. MATERIAL/METHODS: Experimental groups included control, stress+oxytocin, and stress+saline groups. Restraint stress was applied to all the stress groups for 1 h/day, for 7 days. Learning-memory tests were performed after the 7th day. RESULTS: In the stress+oxytocin groups, the process of finding the platform was shorter than in others groups. The stress+saline groups spent less time, whereas the stress+oxytocin groups spent more time, on the target quadrant in the probe trial. In the stress+oxytocin groups thigmotaxis time (indicating anxiety) decreased, but VEGF and BDNF levels increased. A positive correlation was found between VEGF and BDNF levels and the time spent within the target quadrant. CONCLUSIONS: The results indicate that impaired hippocampal learning and memory loss due to chronic restraint stress can be positively affected by intranasal oxytocin.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transtornos Cognitivos/tratamento farmacológico , Hipocampo/metabolismo , Ocitocina/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Ansiedade , Feminino , Hipocampo/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto , Memória/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
Although studies suggest that cognitive functions in the elderly are impaired, elderly people tend to be more successful and wiser in solving emotional problems. In empathy-like behavior models, the observer rat rescues the distressed cage mate by displaying emotional and cognitive ability. The aim of the study was to investigate the changes in empathy-like behavior in older rats in comparison to adult rats. In addition, we wanted to determine the effects of alterations in neurochemicals (such as corticosterone, oxytocin, vasopressin, and their receptor levels) and emotional situations on this behavior. In our study, we initially completed empathy-like behavior tests and emotional tests (open field, elevated plus maze) and performed neurochemical examinations in the serum and brain tissues. In the second step of research, we applied a midazolam (benzodiazepine) treatment to examine the effect of anxiety on empathy-like behavior. In the old rats, we observed that empathy-like behavior deteriorated, and anxiety signs were more pronounced. We detected a positive correlation between the latency in empathy-like behavior and corticosterone levels and v1b receptor levels. The midazolam effect on empathy-like behavior was attenuated by flumazenil (a benzodiazepine receptor antagonist). The recordings of ultrasonic vocalization showed frequencies around 50 kHz emitted by the observer and this was associated with the expectation of social contact. Our results state that compared to adult rats, old rats were more concerned and failed during empathy-like behavior. Midazolam may improve this behavior by anxiolysis.
Assuntos
Ansiolíticos , Midazolam , Humanos , Ratos , Animais , Idoso , Midazolam/farmacologia , Ansiolíticos/farmacologia , Empatia , Corticosterona , Ansiedade/tratamento farmacológico , Comportamento AnimalRESUMO
Oxidative stress plays an important role in the development of complications in diabetes mellitus. Antioxidant therapy has been thought to decrease oxidative stress. The objective of the present study was to explore the effects of melatonin (MLT) on oxidative stress in diabetic rat eye and brain tissue by using immunohistochemical methods. Diabetes was induced by streptozotocin, (STZ, 55 mg/kg/i.p) in adult rats. MLT was given 10 mg/kg/i.p once a day for 2 weeks beginning from the sixth week. Six weeks later, rats were divided into three groups: control (CR), STZ-induced diabetic (STZ), and STZ-induced diabetic group received melatonin (STZ+MLT). Although no significant difference was observed with respect to antioxidant status, NOS activity tended to be higher in the untreated diabetic rats than in the treated rats. It was observed that MLT treatment improved the histopathological changes including apoptosis and oxidative stress in brain and eye in diabetic rat.
Assuntos
Antioxidantes/farmacologia , Encéfalo/metabolismo , Diabetes Mellitus Experimental/metabolismo , Olho/metabolismo , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Olho/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Ratos , Ratos WistarRESUMO
Maternal exercise during pregnancy has been suggested to exert beneficial effects on brain functions of the offspring. Leptin is an adipocytokine which is secreted from adipose tissues and has positive effects on learning, memory, and synaptic plasticity. In this study, pregnant rats were moderately exercised and we observed the effects of this aerobic exercise on their prepubertal and adult offsprings' spatial learning, hippocampal neurogenesis, and expression of leptin. All the pups whose mothers exercised during pregnancy learned the platform earlier and spent longer time in the target quadrant. Their thigmotaxis times were shorter than those measured in the control group. It is shown that hippocampal CA1, CA3 neuron numbers increased in both prepubertal and adult pups, in addition that GD neuron numbers increased in adult pups. Leptin receptor expression significantly increased in the prepubertal male, adult male, and adult female pups. In our study, maternal running during pregnancy resulted in significant increase in the expression of leptin receptor but not in prepubertal female pups, enhanced hippocampal cell survival, and improved learning memory capability in prepubertal and adult rat pups, as compared to the control group. In conclusion, maternal exercise during pregnancy may regulate spatial plasticity in the hippocampus of the offspring by increasing the expression of leptin.
Assuntos
Aprendizagem em Labirinto/fisiologia , Condicionamento Físico Animal/fisiologia , Receptores para Leptina/fisiologia , Fatores Etários , Animais , Região CA1 Hipocampal/fisiologia , Região CA3 Hipocampal/fisiologia , Sobrevivência Celular , Giro Denteado/fisiologia , Feminino , Masculino , Memória/fisiologia , Neurogênese , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Gravidez , Ratos , Ratos Wistar , Fatores Sexuais , Estatísticas não ParamétricasRESUMO
Acetaminophen is one of the most widely used overthecounter drugs worldwide for the treatment of pain and fever. Although acetaminophen use is known to impair hippocampusrelated learning and memory, its effect on anxiety is not clear. Insulinlike growth factor1 (IGF1) and matrix metalloproteinase2 (MMP2) are important for cellular survival, maintenance and tissue integrity. The aim of this study was to investigate the dosedependent effects of acetaminophen on anxiety levels as well as on hippocampus, prefrontal cortex and liver tissue. Doses of 100, 200 and 400 mg/kg acetaminophen were administered to male Sprague Dawley rats for 11 days and anxiety tests were conducted on the last day. Twentyfour hours after the last acetaminophen administration, all animals were sacrificed and hippocampus, prefrontal cortex and liver tissues were removed for analyses. Hippocampal IGF1 and MMP2 levels were shown to decrease only at the highest dose of acetaminophen, which was accompanied by pathological changes in histology. The prefrontal cortex was not affected. Behavioral analyses also did not indicate changes in anxiety levels in the rats. Liver IGF1 and MMP2 levels decreased in all experimental groups. Serum alanine aminotransferase and aspartate aminotransferase levels increased in the 200 mg/kg and 400 mg/kg acetaminophen groups. Our findings showed that varying doses of acetaminophen did not affect the prefrontal cortex or anxiety levels. Further research is needed to elucidate the hippocampal and hepatic protective roles of IGF1 and MMP2 in acetaminophen toxicity and their potential use in therapeutic approaches.
Assuntos
Acetaminofen , Hipocampo , Metaloproteinase 2 da Matriz , Acetaminofen/toxicidade , Alanina Transaminase , Animais , Ansiedade/tratamento farmacológico , Aspartato Aminotransferases , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Fator de Crescimento Insulin-Like I , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
The positive effects of both ketogenic diet (KD) and regular voluntary exercise on anxiety and depression behavior have been recently reported in rodent animals, but the effects of pairing a KD with exercise on depression and anxiety are unknown. In this study, we aimed to investigate the effects of combination of KD and regular voluntary exercise on anxiety and depression-like behavior in Balb/c mice. We've demostrated that anxiety and depression levels decreased in KD-exercised (KD-Ex) mice. ß-hydroxybutyrate (BHB) levels increased while glucose, insulin levels and LDL/HDL ratio decreased in KD-Ex mice. There was a negative correlation between BHB and the time spent in the closed arms of elevated plus maze (EPM) or the time spent in periphery walls of open field test (OFT) and the immobility time in forced swim test (FST) which all of them are indicators of low depression and anxiety levels. There was a positive correlation between LDL/HDL ratio and the time spent in the closed arms of EPM or the immobility time in FST. The immobility time in FST was positively correlated with insulin while the mobility time in FST was negatively correlated with glucose. In conclusion, these results suggest that decline in anxiety and depression-like behaviors resulted from KD with regular voluntary exercise may be associated with increased BHB levels and decreased LDL/HDL ratio and insulin or glucose levels. Further research is necessary for our understanding of the mechanisms by which pairing a KD with voluntary exercise influences brain and behavior.
Assuntos
Ansiedade/terapia , Depressão/terapia , Dieta Cetogênica/métodos , Condicionamento Físico Animal/métodos , Animais , Ansiedade/dietoterapia , Glicemia/metabolismo , Depressão/dietoterapia , Insulina/sangue , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , CorridaRESUMO
It is clearly known that psychological stress is an important threat to health in today's modern societies. Recent studies have shown that acute stress causes an increase in positive social behaviours such as prosocial behaviour and devotion which are components of empathic behaviour. Neuropsychiatric manifestations such as anxiety and depression may affect empathic behaviour. The aim of this study was to investigate the effects of chronic restraint stress on empathy-like behaviour and the histopathological changes in the amygdala, prefrontal cortex in the adrenal glands and thymus, as well as the neurochemical pathways associated with empathy, oxytocin and vasopressin. The chronic stress group was subjected to restraint stress daily for 14 days after all subjects were trained to rescue its stressed cagemate using empathy test equipment for 12 days. It was observed that chronic restraint stress had no effect on empathy-like behaviour in rats. Vasopressin levels in amygdala was increased in chronic stress group compared to control group. Anxiety and depression indicators did not change in both groups. In the open field test, control group spent more time in thigmo zone compared to chronic stress group. Adrenal glands relative weights and apoptotic cell ratios were significantly higher in the chronic stress group compared to the control group (expectedly). Although there was no significant difference in behavioral tests, histopathological changes were detected. In subsequent studies, it is appropriate to examine the effects of different types of stress applications, gender-related changes, and other neurochemical pathways associated with stress and empathy.
Assuntos
Empatia , Restrição Física/psicologia , Comportamento Social , Estresse Psicológico/psicologia , Glândulas Suprarrenais/patologia , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/patologia , Animais , Comportamento Animal , Modelos Animais de Doenças , Humanos , Masculino , Ratos , Estresse Psicológico/patologia , Timo/patologia , Vasopressinas/análise , Vasopressinas/metabolismoRESUMO
Magnesium is being investigated in various clinical conditions and has shown to be effective in some chronic pain models. However, it is not clear if oral magnesium use affects pain perception in acute pain. TLR4's (toll-like receptor) role in pain perception has emerged through its role in immune pathways and ion channels. The aim of this study is to investigate the effect of a single oral dose of magnesium citrate on pain conduction and whether with magnesium, the expression of TLR4 changes in the acute phase. Following a single dose of 66-mg/kg magnesium citrate administration to male Balb-c mice, pain perception (via hot-plate test), motor conduction (via electrophysiological recording, forelimb grip strength, rotarod and open-field tests), and emotional state (via elevated plus maze and forced swim test) were evaluated. In behavioral experiments, the control group was compared with applied magnesium for three different time groups (4, 8, 24 h). TLR4 expression was measured in four groups: control, magnesium (Mg), hot plate (HP), and Mg + HP. Hot plate latency was prolonged in the magnesium group (p < 0.0001) and electrophysiological recordings (p < 0.001) and forelimb grip strength measurement (p < 0.001) determined motor latency. Compared with the untreated hot plate group, TLR4 levels was lower in the brain (p = 0.023) and higher in the sciatic nerve (p = 0.001) in the magnesium-treated hot plate group. Consequently, the study indicated a single dose of magnesium citrate appeared to cause weakening in the transmission and perception of nociceptive pain. TLR4 may act as a regulator in magnesium's effects on pain perception.
Assuntos
Encéfalo/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Limiar da Dor , Receptor 4 Toll-Like , Animais , Encéfalo/metabolismo , Ácido Cítrico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Medição da Dor , Receptor 4 Toll-Like/metabolismoRESUMO
Physical exercise improves learning and memory abilities by increasing the levels of several growth factors in the hippocampus. One growth factor, vascular endothelial growth factor (VEGF), is primarily produced in the muscles and not only increases in the periphery during exercise but can also cross the blood-brain barrier. The aim of this study is to investigate the effects of regular aerobic chronic exercise on different types of muscle fibers and the relationships between learning/memory and muscle induced-VEGF. Following a one-week adaptation period, male rats underwent treadmill training at a speed of 8 m/min for 30 min daily, 3 days a week for 6 weeks. Memory functions were evaluated using the Morris water maze. VEGF, superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) levels were measured in type 1 and type 2 muscle fibers and VEGF levels were also measured in the hippocampus. Exercise positively affected both learning and memory and also increased VEGF levels in both muscle fiber types. Muscle VEGF levels positively correlate with hippocampal learning and hippocampal VEGF levels. Exercise reduced both SOD and MDA levels in type 1 and type 2 muscle fibers, whereas GPx levels decreased only in type 2 muscle fibers. Our findings suggest that regular aerobic exercise elevates VEGF levels and diminishes oxidative stress in both fiber types. Exercise-induced VEGF levels in both type 1 and 2 muscle fibers appear to be associated with the positive effect of exercise on learning and memory function and is accompanied by an increase in VEGF levels in the hippocampus. Further research is needed to elucidate the exact mechanism by which fiber type-specific VEGF mediates hippocampal neurogenesis and angiogenesis.Physical exercise improves learning and memory abilities by increasing the levels of several growth factors in the hippocampus. One growth factor, vascular endothelial growth factor (VEGF), is primarily produced in the muscles and not only increases in the periphery during exercise but can also cross the blood-brain barrier. The aim of this study is to investigate the effects of regular aerobic chronic exercise on different types of muscle fibers and the relationships between learning/memory and muscle induced-VEGF. Following a one-week adaptation period, male rats underwent treadmill training at a speed of 8 m/min for 30 min daily, 3 days a week for 6 weeks. Memory functions were evaluated using the Morris water maze. VEGF, superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) levels were measured in type 1 and type 2 muscle fibers and VEGF levels were also measured in the hippocampus. Exercise positively affected both learning and memory and also increased VEGF levels in both muscle fiber types. Muscle VEGF levels positively correlate with hippocampal learning and hippocampal VEGF levels. Exercise reduced both SOD and MDA levels in type 1 and type 2 muscle fibers, whereas GPx levels decreased only in type 2 muscle fibers. Our findings suggest that regular aerobic exercise elevates VEGF levels and diminishes oxidative stress in both fiber types. Exercise-induced VEGF levels in both type 1 and 2 muscle fibers appear to be associated with the positive effect of exercise on learning and memory function and is accompanied by an increase in VEGF levels in the hippocampus. Further research is needed to elucidate the exact mechanism by which fiber type-specific VEGF mediates hippocampal neurogenesis and angiogenesis.
Assuntos
Hipocampo/metabolismo , Aprendizagem/fisiologia , Memória/fisiologia , Condicionamento Físico Animal/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Comportamento Animal/fisiologia , Cognição/fisiologia , Masculino , Músculo Esquelético/metabolismo , Neurogênese/fisiologia , Neurônios/metabolismo , RatosRESUMO
OBJECTIVES: This study determined the preventive effect of melatonin on the occurrence of experimentally-induced myringosclerosis of the tympanic membrane (TM). MATERIALS AND METHODS: Twenty Wistar albino-type rats weighing approximately 300 g each were randomly separated into two groups and myringotomized on the left TMs: group 1 rats (n=6) received intraperitoneal melatonin injections 10 mg/kg/day whereas group 2 rats (n=12) were treated with physiological serum only. The remaining two rats were served as the control group for histological comparison and standardization. After 15 days of treatment, myringotomized membranes were examined by otomicroscopy and harvested for histopathological evaluation. The functional effect of myringosclerotic plaques in the TMs of the two groups were compared with tympanometric measurements. RESULTS: Tympanic membranes in group 2 revealed extensive myringosclerotic plaques, on the other hand, TMs in group 1 showed faint or no existence of myringosclerosis. The mean magnitude of the maximum admittance from group 2 measured by tympanometry reduced to about 40% of the values obtained from group 1 (Z=-2,067, p=0.041). The mean magnitude of the maximum admittance from melatonin group was very close to the mean tympanometric value of non-myringotomized Wistar albino rats, demonstrating a functional outcome. CONCLUSION: The occurrence of myringosclerosis following experimental myringotomy can be hindered by systemic melatonin treatment.
Assuntos
Melatonina/farmacologia , Miringoplastia/métodos , Timpanoplastia/métodos , Animais , Feminino , Miringoplastia/efeitos adversos , Ratos , Ratos Wistar , Membrana Timpânica/efeitos dos fármacos , Membrana Timpânica/patologia , Membrana Timpânica/cirurgiaRESUMO
Empathy is a multidimensional paradigm, and there currently is a lack of scientific consensus in its definition. In this paper, we review the possibility of compromising data during behavioral neuroscience experiments, including but not limited to those who study empathy. The experimental protocols can affect, and be affected by, empathy and related processes at multiple levels. We discuss several points to help researchers develop a successful translational pathway for behavioral research on empathy. Despite varying in their focus with no widely accepted model, current rodent models on empathy have provided sound translational explanations for many neuropsychiatric proof-of-concepts to date. Research has shown that empathy can be influenced by many parameters, some of which are to be reviewed in this paper. We emphasize the future importance of consistency in modeling proof of concept; efforts to create a multidisciplinary group which would include both bench scientists and clinicians with expertise in neuropsychiatry, and the consideration of empathy as an independent variable in animal behavioral experimental designs which is not the mainstream practice at present.
RESUMO
Vascular endothelial growth factor (VEGF) is the most important regulator of angiogenesis which serves to provide sufficient blood supply, and can trigger both physiological and pathological angiogenesis. Recent studies have shown that VEGF increases in gynecological diseases (such as endometriosis, ovarian, and endometrial cancers) and is a prognostic factor in these pathologies. Therefore, VEGF should be maintained at appropriate levels. Magnesium is used in many gynecological practices (such as eclampsia, preeclampsia, dysmenorrhea, and climacteric symptoms) and the mechanisms of action are still under investigation. Redox status, which can be regulated by magnesium, was shown to affect VEGF expression. The aim of this study was to evaluate the effects of chronic magnesium use on VEGF and oxidative status in the uterus. Magnesium sulfate was administered to rats at doses of 30 mg/kg (intramuscular) for 2 weeks. VEGF, Superoxide dismutase (SOD), Glutathione peroxidase (GPx), and Malondialdehyde (MDA) levels were measured using ELISA; vascular and cellular alterations were determined by histology in the uterine tissue at the metoestrus phase. In the uterine tissue of Mg-treated subjects, magnesium levels increased while VEGF, SOD, GPx, and MDA levels decreased without histological changes. There was a negative correlation between uterine tissue magnesium levels and VEGF, SOD, GPx, and MDA levels. Consequently, the results of this study demonstrated that regular magnesium use decreased VEGF levels in uterus. Decreased VEGF levels were associated with decreased uterine oxidative stress. Chronic magnesium usage may protect the uterine tissue from certain diseases in which angiogenesis is critical.
Assuntos
Sulfato de Magnésio/administração & dosagem , Sulfato de Magnésio/farmacologia , Útero/efeitos dos fármacos , Útero/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Feminino , Injeções Intramusculares , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Útero/patologiaRESUMO
AIM: To investigate the effects of different magnesium forms on tissue damage, cognitive and emotional behavioural impairment after mild traumatic brain injury (TBI). MATERIAL AND METHODS: Rats were divided into 5 groups (control, trauma, magnesium sulphate, magnesium citrate, magnesium acetyl taurate) and following head trauma, empathy-like behaviour, anxiety-like behaviour (elevated plus maze and open field tests), and depression (forced swim test) were measured. The rats were then sacrificed 12 days later. Oxytocin, vasopressin and receptors levels in the amygdala and prefrontal cortex regions were measured. Histopathological damage (with haematoxylin-eosin staining) and apoptosis (with caspase-3 immunohistochemistry) was evaluated. RESULTS: Following head trauma, anxiety-like behaviour and depression tests did not change; empathy-like behaviour deteriorated on the 3rd day and improved gradually on the 6th and 12th days. Oxytocin, vasopressin and vasopressin v1b receptor levels decreased in the amygdala; morphological damage and apoptosis were significant. Magnesium acetyl taurate effectively ameliorated histopathological deteriorations and improved vasopressin and v1b receptor levels in the amygdala. Transient deterioration of empathy-like behaviour was impeded only in magnesium taurate treatment. CONCLUSION: Magnesium acetyl taurate can be a promising candidate agent to prevent structural and functional damage in traumatic brain injury.
Assuntos
Comportamento Animal/efeitos dos fármacos , Concussão Encefálica/patologia , Lesões Encefálicas Traumáticas/patologia , Encéfalo/efeitos dos fármacos , Magnésio/farmacologia , Animais , Encéfalo/metabolismo , Concussão Encefálica/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Feminino , Ratos , Ratos Sprague-Dawley , Receptores de Vasopressinas/metabolismo , Vasopressinas/metabolismoRESUMO
Magnesium, one of the basic elements for the human body, is necessary for many physiological functions. Magnesium deficiency is widely observed as a result of the reduced nutrient content of foods, over-cooking, diseases, drugs, alcohol, and caffeine consumption. Taking a dietary supplement is necessary magnesium deficiency. It has been demonstrated that absorption of organic magnesium compounds is better than absorption of inorganic compounds. The aim of this study is to investigate transitions to tissues of different organic magnesium compounds in different doses and whether there is a difference in the organic acid-bounded compounds (magnesium citrate and magnesium malate) and the amino acid-bounded compounds (magnesium acetyl taurate and magnesium glycinate), associated with transition and bioavailability. In addition, the effects of split dosages of high doses in a high volume of solvent on tissue magnesium levels are being investigated, because galenic formulation problems are regarded to prepare convenient dosage that can be taken once a day. All magnesium compounds were administered as three different doses, 45, 135, and 405 mg/70 kg elemental magnesium, were given per orally to Balbc mice. In a second set of experiments, 405 mg/70 kg high dose was divided into two doses of 202.5 mg/70 kg each and administered every 12 h. Brain, muscle tissues, and serum magnesium levels measured in all experimental groups and control 24 h later. Brain magnesium levels were found increased in all magnesium acetyl taurate administered subjects. Magnesium citrate increased muscle and brain magnesium levels in a dose-independent manner. We showed that dividing high doses of daily administered magnesium compounds did not sufficiently increase tissue magnesium levels. Although passive paracellular mechanism by solvent drag is the main mechanism of Mg absorption, other factors (electrochemical gradient effects, transcellular transporter mechanisms, magnesium status) should be effective on our results. It is necessary for further research on long-term administration of different magnesium compounds and their effect on other tissues.
Assuntos
Compostos de Magnésio/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Compostos de Magnésio/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Distribuição TecidualRESUMO
Magnesium is an element of great importance functioning because of its association with many cellular physiological functions. The magnesium content of foods is gradually decreasing due to food processing, and magnesium supplementation for healthy living has become increasingly popular. However, data is very limited on the bioavailability of various magnesium preparations. The aim of this study is to investigate the bioavailability of five different magnesium compounds (magnesium sulfate, magnesium oxide, magnesium acetyl taurate, magnesium citrate, and magnesium malate) in different tissues. Following a single dose 400 mg/70 kg magnesium administration to Sprague Dawley rats, bioavailability was evaluated by examining time-dependent absorption, tissue penetration, and the effects on the behavior of the animals. Pharmacokinetically, the area under the curve calculation is highest in the magnesium malate. The magnesium acetyl taurate was found to have the second highest area under the curve calculation. Magnesium acetyl taurate was rapidly absorbed, able to pass through to the brain easily, had the highest tissue concentration level in the brain, and was found to be associated with decreased anxiety indicators. Magnesium malate levels remained high for an extended period of time in the serum. The commonly prescribed dietary supplements magnesium oxide and magnesium citrate had the lowest bioavailability when compared to our control group. More research is needed to investigate the bioavailability of magnesium malate and acetyl taurate compounds and their effects in specific tissues and on behavior.
Assuntos
Compostos de Magnésio/metabolismo , Compostos de Magnésio/farmacocinética , Animais , Área Sob a Curva , Disponibilidade Biológica , Suplementos Nutricionais , Compostos de Magnésio/administração & dosagem , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
Background: It is known that regular physical activity reduces anxiety. Low anxiety levels affect mood, emotions, and empathy. Oxytocin is a powerful hormone that regulates social interaction, sexual reproduction, maternalinfant bonding, milk release, empathy, and anxiety. Empathy is an important behavior in the living community; and also important for sportsmen during sportive competition and daily living life, because sportsmen are also role model of people. Aims: To investigate the effects of voluntary physical activity on oxytocin, anxiety, and empathy levels as well as the relationship between them. Study Design: Animal experiment. Methods: Male and female mice were made to exercise in running wheel cages for 6 weeks. Their empathy and anxiety levels were evaluated by using Helping Behavior test and elevated plus maze and open field test, respectively. And then the brain and blood oxytocin levels were measured. Results: Empathy-like behavior was improved in both genders of the exercise groups (door-opening time decreased in both genders of exercise groups, p for both=0.0001). As a response to exercise, both the brain and serum oxytocin levels increased in female mice (both of p=0.0001); however, in males, oxytocin levels increased in only the brain (p<0.05). Anxiety levels decreased in all the exercise groups (increased time spent in the middle area of open field test, both genders, p=0.002; increased time spent in the open arms of elevated plus maze test, females p=0.004, males p=0.0001). There was a strong negative correlation between serum oxytocin levels and door opening time of helping behavior equipment, and moderate negative correlation was found between the brain oxytocin levels and door-opening time of helping behavior equipment in females. However, there was no correlation between both the brain and serum oxytocin levels and empathy behavior in males. But there were very strong positive correlations between low anxiety indicators and both the brain and serum oxytocin levels in both the genders. Conclusion: Voluntary physical activity decreases anxiety and increases empathy-like behavior in mice; which is associated with increased oxytocin levels in female mice but not in male mice. Further research is required to investigate the mechanisms of exercise effect on anxiety and empathic brain pathways in males.
Assuntos
Ocitocina/fisiologia , Condicionamento Físico Animal/fisiologia , Animais , Ansiedade/classificação , Escala de Avaliação Comportamental/estatística & dados numéricos , Encéfalo/patologia , Encéfalo/fisiologia , Modelos Animais de Doenças , Empatia/classificação , Empatia/fisiologia , Feminino , Masculino , Camundongos , Estatísticas não ParamétricasRESUMO
Chronic cigarette smoking affects many tissues negatively. Nicotine in tobacco has negative effects on tissues, kidneys, and eyes especially, where microcirculation is vitally important for the survival and functioning. It is known that appropriate vascular endothelial growth factor (VEGF) and (matrix metalloproteinase 2) MMP2 levels are required for suitable vascularity and enough microcirculation. The aim of this study was to investigate the effect of nicotine on VEGF and MMP2 levels in kidney and eyes, where microcirculation is very important for their function. The nicotine was given into drinking water, to male and female rats for 6 weeks. During the first 2 weeks, the nicotine concentration was 10 mg/L, then was given at a fixed dose of 20 mg/L until the end of the experiment. The VEGF and MMP2 levels were increased in kidney tissue of both genders as a result of given nicotine. MMP2 levels were also increased in the eye tissue for both genders similarly. However, VEGF levels increased in the eye tissue with nicotine in males, whereas it did not change in females. The use of nicotine made VEGF and MMP2 levels increase in kidney tissue in both genders of rats. This increase in VEGF was observed only in male eye tissue, not in females. According to our findings, it can be suggested that nicotine has negative effects on microvascular circulation by increasing VEGF and MMP2 levels. In addition, it should be pointed out that estrogen might have protective effects on female eye tissue. Further studies are necessary to understand the complex relationship between the role of nicotine and estrogen on eye and kidney tissues.
Assuntos
Metaloproteinase 2 da Matriz/metabolismo , Nicotina/toxicidade , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Olho/metabolismo , Feminino , Rim/metabolismo , Masculino , RatosRESUMO
Cerebral ischemia leads to neuronal damage in the hippocampus and cognitive decline. Reactive oxygen species play an important role in the neuronal loss after cerebral ischemia and reperfusion injury. Deprenyl, an irreversible monoamine-oxidase B inhibitor, has antioxidant and neuroprotective effects against reactive oxygen species. In the present study, the effect of deprenyl on spatial memory impairment, oxidative stress and apoptotic neuronal cell death following transient cerebral ischemia in rats was investigated. Transient ischemia was induced by occlusion of left common carotid artery of rats for 30 min and reperfusion for 24 h or 1 week. Rats received intraperitoneal injection of 1 mg/kg deprenyl (n = 24) or equal volume of saline (n = 24) for 14 days before the experiment. Deprenyl treatment attenuated spatial memory deficits following ischemia-reperfusion as measured by the Morris water maze task. Deprenyl treatment elicited a significant decrease in lipid peroxidation and increase in superoxide dismutase activities in ischemic rat brains. The number of TUNEL-positive cells decreased significantly in deprenyl-treated group when compared with the control group. The results show that deprenyl reduces the ischemia-induced oxidative stress and thus prevents spatial memory deficits and apoptotic neuronal cell death when it is administered before ischemia-reperfusion.