Protective effects of melatonin in cisplatin-induced cardiac toxicity: possible role of BDNF-TNF-α signaling pathway

Purpose: The present study explored the role of melatonin in cisplatin-induced cardiac injury along with the possible role of brain-derived neurotrophic factor (BDNF) in melatonin-mediated effects. Methods: Wistar rats were administered cisplatin (10 mg/kg), and cardiac injury was assessed by measuring the levels of cardiac troponin (cTnT) and lactate dehydrogenase (LDH-1).The extent of apoptosis was measured by measuring caspase-3 (pro-apoptotic) and Bcl-2 (anti-apoptotic) in hearts. The levels of BDNF, tumour necrosis factor α (TNF-α) and reduced glutathione were measured in heart. Melatonin (5 and 10 mg/kg) was administered for 15 days, and the role of BDNF was identified by co-administering BDNF inhibitor, ANA-12 (0.25 and 0.5 mg/kg). Results: Melatonin attenuated cTnT and LDH-1 levels along with reduction in caspase-3 and increase in Bcl-2. It also increased cisplatin-induced decrease in BDNF, increase in TNF-α and decrease in reduced glutathione levels. Moreover, ANA-12 abolished the cardioprotective effects, anti-inflammatory and antioxidant effects of melatonin suggesting the role of BDNF in melatonin-mediated effects in cisplatin-induced cardiac injury. Conclusions: Melatonin is useful in cisplatin-induced cardiac injury, which may be due to an increase in BDNF, decrease in inflammation and increase in antioxidant activities.

Effects of intra-dentate gyrus microinjection of myokine irisin on long-term potentiation in male rats / Efeitos da microinjeção da miocina irisina no giro denteado sobre a potenciação a longo prazo em ratos machos

ABSTRACT Induction of long-term potentiation (LTP) increases the storage capacity of synapses in the hippocampal dentate gyrus (DG). Irisin is a myokine generated from FNDC5 (a gene precursor) during exercise. Although intra-cornu ammonis 1 administration of irisin fortifies LTP in mice with Alzheimer's disease, the effects of intra-DG injection of irisin on the LTP in rats remains to be elucidated in vivo. In this study, male Wistar rats were randomly divided into a control group (saline), irisin (0.5, 1, and 1.5 μg/rat), and dimethyl sulfoxide (DMSO). After treatment, the population spike (PS) amplitude and slope of excitatory postsynaptic potentials (EPSP) were measured in the DG of rats in vivo. Moreover, following completion of the experiments, the stimulating and recording sites in the hippocampus were confirmed histologically from brain sections. Furthermore, biochemical assays like malondialdehyde (MDA), total antioxidant capacity (TAC), and total oxidant status (TOS) were evaluated (the antioxidant markers were analyzed in the plasma). Our results suggest that all doses of irisin (0.5, 1, 1.5 μg/rat) caused an increase in the EPSP slope and PS amplitude when compared with the control group. In addition, the results obtained showed that irisin decreased TOS and MDA levels while increasing TAC levels as a marker of lipid peroxidation in plasma. The present report provides direct evidence that irisin affects the activity-dependent synaptic plasticity in the dentate gyrus.

RESUMO A indução de potenciação de longo prazo (LTP) aumenta a capacidade de armazenamento das sinapses no giro denteado (DG) do hipocampo. A irisina é uma miocina gerada a partir do FNDC5 (um precursor genético) durante o exercício. Embora a administração intra-Cornu Ammonis1 de irisina fortaleça a LTP em camundongos com doença de Alzheimer, os efeitos da injeção intra-denteada de irisina sobre a LTP em ratos ainda precisam ser elucidados in vivo. Neste estudo, ratos Wistar machos foram divididos aleatoriamente em um grupo controle (solução salina), irisina (0,5, 1 e 1,5 μg / rato) e dimetilsulfóxido (DMSO). Após o tratamento, a amplitude do pico populacional (PS) e a variação dos potenciais pós-sinápticos excitatórios (EPSP) foram medidos no DG de ratos in vivo. Além disso, após a conclusão das experiências, os locais de estimulação e registro no hipocampo foram confirmados histologicamente a partir de secções do cérebro. Adicionalmente, ensaios bioquímicos como malondialdeído (MDA), capacidade antioxidante total (TAC) e status oxidante total (TOS) foram avaliados (os marcadores antioxidantes foram analisados no plasma). Nossos resultados sugerem que todas as doses de irisina (0,5, 1, 1,5 μg / rato) causaram um aumento na variação da EPSP e na amplitude da PS quando comparadas com o grupo controle. Além disso, os resultados obtidos mostraram que a irisina diminuiu os níveis de TOS e MDA, enquanto aumentou os níveis de TAC como um marcador da peroxidação lipídica no plasma. O presente estudo fornece evidências diretas de que a irisina afeta a plasticidade sináptica dependente de atividade no DG.

Correlación del factor neurotrófico derivado del cerebro con los componentes que integran el síndrome metabólico infantil / Correlation of brain derived neurotrophic factor with the components that integrate the child metabolic syndrome

La obesidad infantil representa un factor importante en el desarrollo del síndrome metabólico (SM). En este sentido el factor neurotrófico derivado del cerebro (BDNF: Brain Derived Neurotrophic Factor) interviene en el metabolismo energético así como en vías que controlan el peso corporal y desórdenes metabólicos. El objetivo de este estudio fue determinar si hay una correlación entre el BDNF con los marcadores que definen al síndrome metabólico en una población infantil de México. Se integraron al estudio 100 niños con un rango de edad de 5-13 años, se estratificaron en tres grupos, normo peso, sobrepeso y obesidad, a los cuales se les determinaron las variables antropométricas, percentil de la tensión arterial sistólica y diastólica, concentraciones séricas de glucosa, triglicéridos, colesterol de alta densidad (HDL) y BDNF. Se aplicó ANOVA y una correlación de Pearson. Los resultados muestran que la prevalencia de SM utilizando los criterios de Cook y Weiss fue del 14%, mientras que por la Federación Internacional de Diabetes (IDF) es del 11%. La circunferencia de cintura, triglicéridos, colesterol HDL, presión arterial sistólica/diastólica y glucosa, mostraron diferencias significativas entre los grupos estudiados (*p<0,001). El BDNF se correlacionó positivamente con la desviación estándar del índice de masa corporal de acuerdo con la edad (DE-IMCE) (p=0,01), el percentil del perímetro de la cintura (p=0,00), la presión arterial sistólica (p=0,01) y las concentraciones plasmáticas de glucosa (p=0,02). Estos datos muestran que existe una correlación entre el BDNF con la DE-IMCE, la circunferencia de la cintura, la presión arterial sistólica y glucosa(AU)

Childhood obesity represents an important factor in the development of metabolic syndrome (MS). In this sense, the brain derived neurotrophic factor (BDNF) is involved in energy metabolism as well as in pathways that control body weight and metabolic disorders. The objective of this study was to determine if there is a correlation between BDNF with the markers that define the metabolic syndrome in a child population in Mexico. The study included 100 children with an age range of 5-13 years, stratified into three groups, normal weight, overweight and obesity, which were determined anthropometric variables, percentile of systolic and diastolic blood pressure, concentrations serum glucose, triglycerides, high density cholesterol (HDL) and BDNF. ANOVA and Pearson correlation were applied. The results show that the prevalence of MS using the Cook and Weiss criteria was 14%, while for the International Diabetes Federation (IDF) it is 11%. Waist circumference, triglycerides, HDL cholesterol, systolic/diastolic blood pressure and glucose showed significant differences between the groups studied (*p<0.001). The BDNF was positively correlated with the standard deviation of the body mass index according to age (DE-IMCE) (p=0.01), the percentile of the waist circumference (p=0.00), systolic blood pressure (p=0.01) and plasma glucose concentrations (p=0.02). These data show that there is a correlation between BDNF with DE-IMCE, waist circumference, systolic blood pressure and glucose(AU)

Expressão de neurotrofinas e de seus receptores no osteossarcoma primário / Expression of neurotrophins and their receptors in primary osteosarcoma

RESUMO Objetivo: determinar a expressão de neurotrofinas e seus receptores tirosina quinases em pacientes com osteossarcoma (OS) e sua correlação com desfechos clínicos. Métodos: biópsias de tumores primários de pacientes com OS tratados em uma única instituição, consecutivamente, entre 2002 e 2015, foram analisados através de imuno-histoquímica para expressão de receptores de tirosina quinase A e B (TrKA e TrKB), fator de crescimento neural (NGF) e fator neurotrófico derivado do cérebro (BDNF). De forma independente, dois patologistas classificaram os marcadores de imuno-histoquímica como negativos (negativos e focais fracos) ou positivos (moderado focal/difuso ou forte focal/difuso). Resultados: foram analisados dados de 19 pacientes (10 do sexo feminino e 9 do masculino) com mediana de idade de 12 anos (5 a 17,3 anos). Dos tumores, 83,3% estavam localizados em membros inferiores e 63,2% dos pacientes eram metastáticos ao diagnóstico. A sobrevida global em cinco anos foi de 55,3%. BDNF foi positivo em 16 pacientes (84%) e NGF em 14 pacientes (73%). TrKA e TrKB apresentaram coloração positiva em quatro (21,1%) e oito (42,1%) pacientes, respectivamente. A análise de sobrevida não demonstrou diferença significativa entre receptores TrK e neurotrofinas. Conclusão: amostras de OS primário expressam neurotrofinas e receptores TrK através de imuno-histoquímica. Estudos futuros podem auxiliar na identificação do papel das mesmas na patogênese do OS e determinar se há possível correlação prognóstica.

ABSTRACT Objective: to determine the expression of neurotrophins and their tyrosine-kinase receptors in patients with osteosarcoma (OS) and their correlation with clinical outcomes. Methods: we applied immunohistochemistry to biopsy specimens of patients consecutively treated for primary OS at a single institution between 2002 and 2015, analyzing them for expression receptors of tyrosine kinase A and B (TrKA and TrKB), neural growth factor (NGF) and brain derived neurotrophic factor (BDNF). Independently, two pathologists classified the immunohistochemical markers as negative (negative or weak focal) or positive (moderate focal/diffuse or strong focal/diffuse). Results: we analyzed data from 19 patients (10 females and 9 males), with median age of 12 years (5 to 17.3). Tumors' location were 83.3% in the lower limbs, and 63.2% of patients had metastases at diagnosis. Five-year overall survival was 55.3%. BDNF was positive in 16 patients (84%) and NGF in 14 (73%). TrKA and TrKB presented positive staining in four (21,1%) and eight (42,1%) patients, respectively. Survival analysis showed no significant difference between TrK receptors and neurotrophins. Conclusion: primary OS samples express neurotrophins and TrK receptors by immunohistochemistry. Future studies should explore their role in OS pathogenesis and determine their prognostic significance in larger cohorts.

Difference of brain-derived neurotrophic factor expression and pyramid cell count during mastication of food with varying hardness

Abstract Previous studies suggested that mastication activity can affect learning and memory function. However, most were focused on mastication impaired models by providing long-term soft diet. The effects of chewing food with various hardness, especially during the growth period, remain unknown. Objective: To analyze the difference of hippocampus function and morphology, as characterized by pyramidal cell count and BDNF expression in different mastication activities. Materials and Methods: 28-day old, post-weaned, male-Wistar rats were randomly divided into three groups (n=7); the first (K0) was fed a standard diet using pellets as the control, the second (K1) was fed soft food and the third (K2) was fed hard food. After eight weeks, the rats were decapitated, their brains were removed and placed on histological plates made to count the pyramid cells and quantify BDNF expression in the hippocampus. Data collected were compared using one-way ANOVA. Results: Results confirmed the pyramid cell count (K0=169.14±27.25; K1=130.14±29.32; K2=128.14±39.02) and BDNF expression (K0=85.27±19.78; K1=49.57±20.90; K2=36.86±28.97) of the K0 group to be significantly higher than that of K1 and K2 groups (p<0.05); no significant difference in the pyramidal cell count and BNDF expression was found between K1 and K2 groups (p>0.05). Conclusion: A standard diet leads to the optimum effect on hippocampus morphology. Food consistency must be appropriately suited to each development stage, in this case, hippocampus development in post-weaned period.

Papel del factor neurotrófico de origen cerebral y de la neurotropina-3 en la relación de Chlamydophila pneumoniae con la esquizofrenia / The relationship of Chlamydophila pneumoniae with schizophrenia: The role of brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) in this relationship

Several pathogens have been suspected of playing a role in the pathogenesis of schizophrenia. Chronic inflammation has been proposed to occur as a result of persistent infection caused by Chlamydophila pneumoniae cells that reside in brain endothelial cells for many years. It was recently hypothesized that brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) may play prominent roles in the development of schizophrenia. NT-3 and BDNF levels have been suggested to change in response to various manifestations of infection. Therefore, we aimed to elucidate the roles of BDNF and NT3 in the schizophrenia-C. pneumoniae infection relationship. RT-PCR, immunofluorescence and ELISA methods were used. Fifty patients suffering from schizophrenia and 35 healthy individuals were included as the patient group (PG) and the healthy control group (HCG), respectively. We detected persistent infection in 14 of the 50 individuals in the PG and in 1 of the 35 individuals in the HCG. A significant difference was found between the two groups (p < 0.05). Twenty-two individuals in the PG and 13 in the HCG showed seropositivity for past C. pneumoniae infection, and no difference was observed between the groups (p > 0.05). C. pneumoniae DNA was not detected in any group. A significant difference in NT-3 levels was observed between the groups, with very low levels in the PG (p < 0.001). A significant difference in BDNF levels was also found, with lower levels in the PG (p < 0.05). The mean serum NT-3 level was higher in the PG cases with C. pneumoniae seropositivity than in seronegative cases; however, this difference was not statistically significant (p > 0.05). In conclusion, we suggest that NT-3 levels during persistent C. pneumoniae infection may play a role in this relationship.

Existe la sospecha de que algunos patógenos pueden desempeñar un papel en la patogénesis de la esquizofrenia; en ese contexto, se ha propuesto que la infección persistente causada por células de Chlamydophila pneumoniae presentes en las células endoteliales cerebrales durante muchos años lleva a la inflamación crónica. Recientemente se ha planteado la hipótesis de que el factor neurotrófico de origen cerebral (BDNF, por sus siglas en inglés) y la neurotropina-3 (NT-3) podrían estar implicados en el desarrollo de la esquizofrenia, y se ha sugerido que sus niveles se modifican en respuesta a diversas manifestaciones de la infección. En esta investigación intentamos esclarecer el papel que desempeñan el BDNF y la NT3 en la relación entre la esquizofrenia y la infección por C. pneumoniae. Se utilizaron métodos de RT-PCR, inmunofluorescencia y ELISA. Se incluyeron 50 pacientes con esquizofrenia y 35 individuos sanos como grupo de pacientes (GP) y grupo de controles sanos (GCS), respectivamente. Detectamos una infección persistente en 14 sujetos del GP y en 1 de los del GCS, lo que constituyó una diferencia significativa (p < 0,05). Veinte participantes del GP y 13 del GCS fueron seropositivos para una infección pasada por C. pneumoniae, diferencia no significativa (p > 0,05). No se detectó ADN de C. pneumoniae en ninguno de los dos grupos. Se observó una diferencia significativa entre los grupos en los niveles de NT-3, que fueron muy bajos en el GP (p < 0,001), y de BDNF, inferiores en el GP (p < 0,05). La concentración sérica media de NT-3 fue mayor en los individuos seropositivos para C. pneumoniae en comparación con los seronegativos, pero esta diferencia no alcanzó significación estadística (p > 0,05). Sugerimos que los niveles de NT-3 durante una infección persistente por C. pneumoniae pueden estar implicados en la relación de Chlamydophila pneumoniae con la esquizofrenia.

Grape juice increases the BDNF levels but not alter the S100B levels in hippocampus and frontal cortex from male Wistar Rats

ABSTRACT Several studies have shown that a high consumption of vegetables and fruits is consistently associated with a low risk of oxidative stress-induced diseases, which includes some degenerative diseases such as amyotrophic lateral sclerosis, Alzheimer and Parkinson. Therefore, the objective of this study is to verify the effects of conventional and organic grape juice in the modulation of the neurotrophic factor (BDNF) and astrocytic markers protein (S100B) in hippocampus and frontal cortex of Wistar rats. In this study, 24 male Wistar rats were divided into three groups. To the first one, it was given organic purple grape juice; to the second, conventional grape juice, while the last one received only saline. After 30 days, all rats were sacrificed and hippocampus and frontal cortex were dissected. The animals that received organic and conventional grape juice showed, in frontal cortex, an elevated BNDF levels in relation to saline group. However, S100B levels did not change. These results showed that grape juices are able to modulate important marker in brain tissue, and could be an important factor to prevent brain diseases.

Histone deacetylase activity and brain-derived neurotrophic factor (BDNF) levels in a pharmacological model of mania

Objective: In the present study, we aimed to examine the effects of repeated D-amphetamine (AMPH) exposure, a well-accepted animal model of acute mania in bipolar disorder (BD), and histone deacetylase (HDAC) inhibitors on locomotor behavior and HDAC activity in the prefrontal cortex (PFC) and peripheral blood mononuclear cells (PBMCs) of rats. Moreover, we aimed to assess brain-derived neurotrophic factor (BDNF) protein and mRNA levels in these samples. Methods: We treated adult male Wistar rats with 2 mg/kg AMPH or saline intraperitoneally for 14 days. Between the 8th and 14th days, rats also received 47.5 mg/kg lithium (Li), 200 mg/kg sodium valproate (VPT), 2 mg/kg sodium butyrate (SB), or saline. We evaluated locomotor activity in the open-field task and assessed HDAC activity in the PFC and PBMCs, and BDNF levels in the PFC and plasma. Results: AMPH significantly increased locomotor activity, which was reversed by all drugs. This hyperactivity was associated with increased HDAC activity in the PFC, which was partially reversed by Li, VPT, and SB. No differences were found in BDNF levels. Conclusion: Repeated AMPH administration increases HDAC activity in the PFC without altering BDNF levels. The partial reversal of HDAC increase by Li, VPT, and SB may account for their ability to reverse AMPH-induced hyperactivity. .

Leprosy patients: neurotrophic factors and axonal markers in skin lesions / Pacientes com hanseníase: fatores neurotróficos e marcadores axonais em lesões de pele

Neurotrophins are growth factors with crucial roles in neural pathophysiology. These mediators functionally modulate nociceptive fibers, and changes in neurotrophins expression have been correlated with early loss of nociception in leprosy. This study investigated the expression of NGF, BDNF, and NT3 in dermal nerves of leprosy patients. Characterization of Remak bundles was achieved by p75NTR, and axonal markers NF-L and PGP 9.5 immunostaining. Clinical parameters of neural impairment have been evaluated by Semmes-Wenstein monofilaments. Our findings demonstrated decrease of NGF in borderline leprosy, when compared to control specimens. Similar results were observed in PGP 9.5 expression (borderline: p<0.001 and lepromatous: p<0.05) and NF-L (lepromatous: p<0.05), suggesting advanced Remak bundles degeneration in multibacillary leprosy. It has also been observed positive correlation between p75NTR and PGP 9.5, indicating association between Schwann cells and axons in Remak bundles. Present data indicate that neurotrophins imbalance may participate in the establishment of peripheral nerve damage.

Neurotrofinas são fatores de crescimento com papel fundamental na fisiopatologia neural. Esses mediadores modulam funcionalmente fibras nociceptivas. Mudanças em sua expressão têm sido relacionadas à perda precoce da nocicepção na hanseníase. Este estudo investigou a expressão de NGF, BDNF e NT3 em nervos dérmicos de pacientes hansenianos. A caracterização de fibras nervosas não mielinizadas foi feita por p75NTR e marcadores axonais NF-L e PGP 9.5. Os parâmetros clínicos de dano neural foram avaliados por monofilamentos Semmes-Wenstein. Nossos achados demonstram diminuição de NGF nos pacientes dimorfos em comparação aos controles. Resultados similares foram observados para PGP 9.5 (dimorfos: p<0,001; virchowianos: p<0,05) e NF-L (virchowianos: p<0.05), sugerindo degeneração avançada das terminações nervosas na hanseníase multibacilar. Foi observada correlação positiva entre p75NTR e PGP 9.5, indicando associação entre células de Schwann e axônios em fibras nervosas não mielinizadas. Os resultados indicam que o desequilíbrio na expressão das neurotrofinas pode participar do dano neural periférico.

Marcadores periféricos e a fisiopatologia do transtorno bipolar / Peripheral markers and the pathophysiology of bipolar disorder

INTRODUÇÃO: O entendimento da fisiopatologia do transtorno bipolar vem tendo avanços consistentes nos últimos anos. Um enfoque na relação entre carga alostática e alterações sistêmicas vem tomando corpo, com o objetivo de se entender a frequente progressão da doença. Proeminentes entre os mediadores periféricos têm sido as moléculas que poderiam ser amplamente agrupadas em neurotrofinas, marcadores de estresse oxidativo e marcadores inflamatórios. OBJETIVO: Descrever achados recentes em relação à fisiopatologia sistêmica do transtorno bipolar, com enfoque especial em estudos brasileiros, tentando articular uma visão coerente do conhecimento atual do campo. MÉTODO: Revisão narrativa da literatura relacionada a neurotrofinas, estresse oxidativo e marcadores inflamatórios no transtorno bipolar. RESULTADOS: Diversas fontes de evidência, provenientes tanto de estudos pré-clínicos quanto clínicos, revelam consistentemente alterações sistêmicas no transtorno bipolar. Os achados são especialmente robustos em pacientes com múltiplos episódios. Nesses, alterações relacionadas a episódios de mania e depressão são notáveis em neurotrofinas e dano oxidativo a lipídeos. Um número menor de estudos mostra alterações no sistema imune, em particular estados pró-inflamatórios. CONCLUSÃO: Alterações sistêmicas que correlacionam o transtorno bipolar a comorbidade clínica, disfunção cognitiva, incapacidade e mortalidade precoce começam a ser traçadas. Estudos envolvendo desenhos longitudinais, amostras populacionais e ensaios clínicos envolvendo marcadores periféricos devem ser incorporados no futuro próximo e reforçar a validade de uma noção de envolvimento multissistêmico no transtorno bipolar.

INTRODUCTION: The understanding of the pathophysiology of bipolar disorder has steadily advanced in the past few years. Thereby, a focus on allostatic load and systemic changes has appeared, with the aim to understand illness progression. Amongst the peripheral markers, molecules that can be widely classified into neurotrophins, oxidadive stress markers, and inflammation markers have been elevated. OBJECTIVE: To describe recent findings regarding the systemic pathophysiology of bipolar disorder, with a special focus on Brazilian studies and to create a coherent view of the current knowledge in the field. METHOD: Narrative review of the literature regarding neurotrophins, oxidative stress, and inflammatory markers in bipolar disorder. RESULTS: A diverse body of evidence, based on both pre-clinical and clinical studies, reveals consistent systemic changes in bipolar disorder. The findings are particularly robust in patients after multiple episodes. Thereby, remarkable changes related to manic and depressive episodes were found in neurotrophins and oxidative damage to lipids. Regarding to immune system alterations, in particular pro-inflammatory states, the literature is less consistent. DISCUSSION: Systemic changes that link bipolar disorder to clinical comorbidity, cognitive dysfunction, disability and early mortality are becoming evident. In the near future, longitudinal studies with population-based samples and clinical trials incorporating biomarkers are needed to shed light upon the notion of a multisystem involvement in bipolar disorder.