Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 170.107
Filtrar
1.
Braz. j. biol ; 84: e249617, 2024. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345540

RESUMO

Abstract Hibernation is a natural condition of animals that lives in the temperate zone, although some tropical lizards also experience hibernation annually, such as the lizard native from South America, Salvator merianae, or "tegu" lizard. Even though physiological and metabolic characteristic associated with hibernation have been extensively studied, possible alterations in the red blood cells (RBC) integrity during this period remains unclear. Dehydration and fasting are natural consequences of hibernating for several months and it could be related to some cellular modifications. In this study, we investigated if the osmotic tolerance of RBCs of tegu lizard under hibernation is different from the cells obtained from animals while normal activity. Additionally, we indirectly investigated if the RBCs membrane of hibernating tegus could be associated with oxidation by quantifying oxidized biomolecules and the activity of antioxidant enzymes. Our findings suggest that RBCs are more fragile during the hibernation period, although we did not find evidence of an oxidative stress scenario associated with the accentuated fragility. Even though we did not exclude the possibility of oxidative damage during hibernation, we suggested that an increased RBCs volume as a consequence of hypoosmotic blood during hibernation could also affect RBCs integrity as noted.


Resumo A hibernação é uma condição natural dos animais que vivem na zona temperada, embora alguns lagartos tropicais também experenciem hibernação anualmente, como é o caso do lagarto nativo da América do Sul, Salvator merianae ou "teiú". Embora as características fisiológicas e metabólicas associadas à hibernação tenham sido amplamente estudadas, possíveis alterações na integridade das hemácias durante esse período ainda permanecem obscuras. A desidratação e o jejum são consequências naturais da hibernação por vários meses e podem estar relacionadas a algumas modificações celulares. Neste estudo, investigamos se a tolerância osmótica de hemácias do lagarto teiú sob hibernação são diferentes das células obtidas de animais em atividade normal. Além disso, investigamos indiretamente por meio da quantificação de biomoléculas oxidadas e da atividade de enzimas antioxidantes se a membrana das hemácias dos teiús em hibernação poderia estar associada à oxidação. Nossos resultados sugerem que as hemácias possuem maior fragilidade durante o período de hibernação, embora não tenhamos encontrado evidências de um cenário de estresse oxidativo associado à essa fragilidade acentuada. Embora não tenhamos excluído a possibilidade de dano oxidativo durante a hibernação, sugerimos que um aumento no volume das hemácias como consequência de sangue hipoosmótico durante a hibernação também poderia afetar a integridade de hemácias, tal como foi observado.


Assuntos
Animais , Hibernação , Lagartos , Oxirredução , Estresse Oxidativo , Eritrócitos
2.
Braz. j. biol ; 84: e250936, 2024. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345557

RESUMO

Abstract This study was carried out to evaluate the effect of Glutamine, as a dipeptide or a free amino acid form, on the progression of burn injuries in rats. Thirty male Wistar rats were burned with a comb metal plate heated in boiling water (98 °C) for three minutes, creating four rectangular full-thickness burn areas separated by three unburned interspaces (zone of stasis) in both dorsum sides. The animals were randomized into three groups (n=10): saline solution (G1-Control) and treated groups that orally received Glutamine as dipeptide (G2-Dip) or free amino acid (G3-FreeAA). Two and seven days after burn injury, lesions were photographed for unburned interspaces necrosis evolution assessment. Seven days after injury, glutathione seric was measured and histopathological analysis was performed. By photographs, there was a significant reduction in necrosis progression in G3-Free-AA between days two and seven. Histopathological analysis at day 7 showed a significantly higher stasis zone without necrosis and a higher number of fibroblasts in G2-Dip and G3-FreeAA compared with G1-Control. Also, glutathione serum dosage was higher in G2-Dip. The plasmatic glutathione levels were higher in the G2-Dip than the G1-Control, and there was a trend to higher levels in G3-FreeAA. The reduction in histological lesions, greater production of fibroblasts, and greater amounts of glutathione may have benefited the evolution of burn necrosis, which showed greater preservation of interspaces.


Resumo Este estudo foi realizado para avaliar o efeito da Glutamina, como um dipeptídeo ou forma de aminoácido livre, na progressão de queimaduras em ratos. Trinta ratos Wistar machos foram queimados com um pente de metal aquecido em água fervente (98 °C) por três minutos, criando quatro áreas retangulares queimadas separadas por três interesespaços não queimados (zona de estase) em ambos os lados do dorso. Os animais foram randomizados em três grupos (n = 10): solução salina (G1-Controle) e grupos tratados que receberam glutamina via oral como dipeptídeo (G2-Dip) ou aminoácido livre (G3-FreeAA). Dois e sete dias após a queimadura, as lesões foram fotografadas para avaliação da evolução da necrose entre os espaços não queimados. Sete dias após a lesão, foi dosada a glutationa sérica e realizada análise histopatológica. Pelas fotografias, houve uma redução significativa na progressão da necrose no G3-Free-AA entre os dias dois e sete. A análise histopatológica no dia 7 mostrou uma zona de estase significativamente maior sem necrose e número mais elevado de fibroblastos em G2-Dip e G3-FreeAA em comparação com G1-Controle. Os níveis plasmáticos de glutationa foram maiores no G2-Dip em relação ao G1-Controle, e houve tendência a níveis mais elevados no G3-FreeAA. A redução das lesões histológicas, maior produção de fibroblastos, maior quantidade de glutationa podem ter beneficiado a evolução da necrose da queimadura, que mostrou maior preservação dos interespaços.


Assuntos
Animais , Masculino , Ratos , Queimaduras/tratamento farmacológico , Glutamina , Ratos Wistar , Dipeptídeos , Modelos Animais de Doenças , Aminoácidos
3.
Braz. j. biol ; 84: e253696, 2024. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355862

RESUMO

Abstract Transplanting time and genotype contribute to improving crop yield and quality of eggplant (Solanum melongena L.). A field experiment was conducted to investigate the impact of foliar applied of triacontanol (TRIA) and eggplant genotypes 25919, Nirala, 28389 and Pak-10927,transplanted on 1 March,15 March, and 1 April on exposure to high air temperature conditions. The experiment was performed according to Randomized Complete Block Design and the data was analyzed by using Tuckey,s test . The TRIA was applied at 10µM at flowering stage; distilled water was used as the control. Rate of photosynthesis and transpiration, stomatal conductance, water use efficiency, and effects on antioxidative enzymes (superoxide dismutase, catalase and peroxidase) were evaluated. The 10µM TRIA increased photosynthesis rate and water use efficiency and yield was improved in all genotypes transplanted at the different dates. Foliar application of 10µM TRIA increased antioxidative enzyme activities (SOD, POD & CAT) and improved physiological as well as biochemical attributes of eggplant genotypes exposed to high heat conditions. Highest activity of dismutase enzyme 5.41mg/1g FW was recorded in Nirala genotype in second transplantation. Whereas, lowest was noted in PAK-10927 (2.30mg/g FW). Maximum fruit yield was found in accession 25919 (1.725kg per plant) at 1st transplantation with Triacontanol, whereas accession PAK-10927 gave the lowest yield (0.285 kg per plant) at control treatment on 3rd transplantation. Genotype, transplanting date and application of TRIA improved growth, yield and quality attributes under of heat stress in eggplant.


Resumo O tempo de transplante e o genótipo contribuem para melhorar a produtividade e a qualidade da cultura da berinjela (Solanum melongena L.). Um experimento de campo foi conduzido para investigar o impacto da aplicação foliar de triacontanol (TRIA) e genótipos de berinjela 25919, Nirala, 28389 e Pak-10927, transplantados em 1 de março, 15 de março e 1 de abril de exposição a condições de alta temperatura do ar. O experimento foi realizado de acordo com o Randomized Complete Block Design e os dados foram analisados pelo teste de Tuckey. O TRIA foi aplicado a 10 µM na fase de floração; água destilada foi utilizada como controle. Taxa de fotossíntese e transpiração, condutância estomática, eficiência do uso da água e efeitos sobre as enzimas antioxidantes (superóxido dismutase, catalase e peroxidase) foram avaliados. O TRIA 10 µM aumentou a taxa de fotossíntese e a eficiência do uso da água e o rendimento foi melhorado em todos os genótipos transplantados nas diferentes datas. A aplicação foliar de TRIA 10µM aumentou as atividades das enzimas antioxidantes (SOD, POD e CAT) e melhorou os atributos fisiológicos e bioquímicos de genótipos de berinjela expostos a condições de alto calor. A atividade mais elevada da enzima dismutase 5,41mg / 1g FW foi registrada no genótipo Nirala no segundo transplante. Considerando que o mais baixo foi observado em PAK-10927 (2,30 mg / g FW). A produtividade máxima de frutos foi encontrada no acesso 25919 (1,725 ​​kg por planta) no 1º transplante com Triacontanol, enquanto o acesso PAK-10927 deu a menor produção (0,285 kg por planta) no tratamento de controle no 3º transplante. Genótipo, data de transplante e aplicação de TRIA, melhoramento do crescimento, rendimento e atributos de qualidade sob estresse térmico em berinjela.


Assuntos
Solanum melongena/genética , Solanum melongena/metabolismo , Fotossíntese , Resposta ao Choque Térmico , Álcoois Graxos , Antioxidantes/metabolismo , Antioxidantes/farmacologia
4.
Braz. j. biol ; 84: e257739, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355883

RESUMO

Abstract Under salt stress conditions, plant growth is reduced due to osmotic, nutritional and oxidative imbalance. However, salicylic acid acts in the mitigation of this abiotic stress by promoting an increase in growth, photosynthesis, nitrogen metabolism, synthesis of osmoregulators and antioxidant enzymes. In this context, the objective was to evaluate the effect of salicylic acid doses on the growth and physiological changes of eggplant seedlings under salt stress. The experiment was conducted in a greenhouse, where the treatments were distributed in randomized blocks using a central composite matrix Box with five levels of electrical conductivity of irrigation water (CEw) (0.50; 1.08; 2.50; 3.92 and 4.50 dS m-1), associated with five doses of salicylic acid (SA) (0.00; 0.22; 0.75; 1.28 and 1.50 mM), with four repetitions and each plot composed of three plants. At 40 days after sowing, plant height, stem diameter, number of leaves, leaf area, electrolyte leakage, relative water content, and total dry mass were determined. ECw and SA application influenced the growth and physiological changes of eggplant seedlings. Increasing the ECw reduced growth in the absence of SA. Membrane damage with the use of SA remained stable up to 3.9 dS m-1 of ECw. The relative water content independent of the CEw increased with 1.0 mM of SA. The use of SA at the concentration of 1.0 mM mitigated the deleterious effect of salinity on seedling growth up to 2.50 dS m-1 of ECw.


Resumo Em condições de estresse salino, o crescimento das plantas é reduzido, em virtude, do desequilíbrio osmótico, nutricional e oxidativo. Contudo, o ácido salicílico atua na mitigação desse estresse abiótico por promover incremento no crescimento, fotossíntese, metabolismo do nitrogênio, síntese de osmorreguladores e enzimas antioxidantes. Nesse contexto, objetivou-se avaliar o efeito de doses de ácido salicílico sobre o crescimento e alterações fisiológicas de mudas de berinjela sob estresse salino. O experimento foi conduzido em casa de vegetação, onde os tratamentos foram distribuídos em blocos ao acaso utilizando uma matriz composta central Box com cinco níveis de condutividade elétrica da água de irrigação (CEa) (0,50; 1,08; 2,50; 3,92 e 4,50 dS m-1), associada a cinco doses de ácido salicílico (AS) (0,00; 0,22; 0,75; 1,28 e 1,50 mM), com quatro repetições e cada parcela composta por três plantas. Aos 40 dias após a semeadura, foram determinados a altura da planta, diâmetro do caule, número de folhas, área foliar, vazamento de eletrólito, teor relativo de água e massa seca total. A CEa e a aplicação de AS influenciaram no crescimento e nas alterações fisiológicas das mudas de berinjela. O aumento da CEa reduziu o crescimento na ausência de AS. O dano de membrana com o uso de AS manteve-se estável até 3,9 dS m-1 de CEa. O conteúdo relativo de água independentemente da CEa aumentou com 1 mM de SA. O uso de AS na concentração de 1 mM mitigou o efeito deletério da salinidade no crescimento das mudas até 2,50 dS m-1 de CEa.


Assuntos
Ácido Salicílico/farmacologia , Solanum melongena/metabolismo , Fotossíntese , Estresse Fisiológico , Folhas de Planta/metabolismo , Plântula , Salinidade , Tolerância ao Sal , Antioxidantes/metabolismo
5.
Braz. j. biol ; 84: e253083, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360201

RESUMO

Phosphorus (P) use efficiency is crucial for sorghum production. P acquisition efficiency is the most important component of P use efficiency. The early-stage evaluation of plant development is a useful tool for identifying P-efficient genotypes. This study aimed to identify sorghum hybrids that are efficient in P use efficiency and assess the genetic diversity among hybrids based on traits related to P acquisition efficiency. Thus, 38 sorghum hybrids and two inbred lines (checks) were evaluated under low and high P in a paper pouch system with nutrient solution. Biomass and root traits related to P efficiency were measured. There was no interaction between genotypes and P levels concerning all evaluated traits. The biomass and root traits, except root diameter, presented smaller means under low P than high P. Efficient and inefficient hybrids under each P level were identified. The genetic diversity assessment grouped these genotypes in different clusters. The hybrids AG1090, MSK326, AG1060, 1G100, AS 4639, DKB 540, and DKB 590 were superior under low-P and high-P. Hybrids SC121, 1236020 e 1167017 presented the lowest means than all other hybrids, under both conditions. The evaluated hybrids showed phenotypic diversity for traits related to P acquisition, such as root length and root surface area, which can be useful for establishing selection strategies for sorghum breeding programs and increasing P use efficiency.


A eficiência do uso do fósforo (P) é fundamental para a produção de sorgo. A avaliação no estágio inicial do desenvolvimento da planta é uma ferramenta útil para a identificação de genótipos eficientes de P. Este trabalho teve como objetivo identificar híbridos de sorgo que sejam eficientes ao uso de P e avaliar a diversidade genética entre os híbridos com base em características relacionadas à eficiência de aquisição de P. Assim, 38 híbridos de sorgo e duas linhagens (testemunhas) foram avaliados sob baixo e alto P em sistema de pastas de papel com solução nutritiva. Características de biomassa e de raiz relacionadas à eficiência de P foram mensuradas. Não houve interação entre genótipos e níveis de P em todas as características avaliadas. As características de biomassa e raiz, exceto o diâmetro da raiz, apresentaram médias menores sob baixo P em comparação com alto P. Híbridos eficientes e ineficientes sob cada nível de P foram identificados e agrupados quanto à diversidade genética. Os híbridos AG1090, MSK326, AG1060, 1G100, AS 4639, DKB 540 e DKB 590 foram superiores sob baixo-P e alto-P. Os híbridos SC121, 1236020 e 1167017 apresentaram as menores médias que todos os outros híbridos, em ambas condições. Os híbridos avaliados apresentaram diversidade fenotípica para características relacionadas à aquisição de P, como comprimento e área superficial da raiz, o que pode ser útil para estabelecer estratégias de seleção para programas de melhoramento de sorgo e aumentar a eficiência de uso do P.


Assuntos
Fósforo , Variação Genética , Hidroponia , Sorghum/crescimento & desenvolvimento
6.
Braz. j. biol ; 84: e254646, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360224

RESUMO

Chronic stress (CS) can contribute to dysfunction in several organs including liver and kidney. This study was performed to investigate the changes in serum biochemistry, histological structure, as well as in localization of tyrosine phosphorylated proteins (TyrPho) and Heat shock protein 70 (Hsp-70) in liver and kidney tissues of CS rats induced by two stressors (restrained and force swimming) for 60 consecutive days. Samples of blood, liver, and kidney were collected from adult male Sprague-Dawley rats in each group. Our results showed that serum biochemical parameters including corticosterone, blood sugar, urea nitrogen, creatinine, cholesterol, triglyceride, HDL-C, LDL-C, ALT, AST, alkaline phosphatase in CS group were significantly different from that in normal group in both liver and kidney tissues. Although histological structure was not changed. TyrPho expression was significantly increased in liver lysate but significantly decreased in kidney. Hsp-70 expression in liver increased whereas in kidney decreased. In conclusion, CS can induce changes in liver and kidney functions.


O estresse crônico (SC) pode contribuir para a disfunção em vários órgãos, incluindo fígado e rim. Este estudo foi realizado para investigar as alterações na bioquímica sérica, estrutura histológica, bem como na localização de proteínas tirosina fosforiladas (TyrPho) e proteína de choque térmico 70 (Hsp-70) em tecidos hepáticos e renais de ratos CS induzidas por dois estressores (restrito e natação forçada) por 60 dias consecutivos. Amostras de sangue, fígado e rim foram coletadas de ratos Sprague-Dawley machos adultos em cada grupo. Nossos resultados mostraram que os parâmetros bioquímicos séricos, incluindo corticosterona, glicemia, nitrogênio ureico, creatinina, colesterol, triglicerídeos, HDL-C, LDL-C, ALT, AST, fosfatase alcalina no grupo CS foram significativamente diferentes do grupo normal em ambos os fígados e tecidos renais. Embora a estrutura histológica não tenha sido alterada, a expressão de TyrPho aumentou significativamente no lisado hepático, mas diminuiu significativamente no rim. A expressão de Hsp-70 no fígado aumentou, enquanto que no rim diminuiu. Em conclusão, a CS pode induzir alterações nas funções hepáticas e renais.


Assuntos
Ratos , Estresse Fisiológico , Ratos Sprague-Dawley , Rim/anatomia & histologia , Fígado/anatomia & histologia
7.
Int. j. clin. health psychol. (Internet) ; 23(2): 1-9, abr.-jun. 2023. tab, graf, ilus
Artigo em Inglês | IBECS | ID: ibc-213885

RESUMO

Background/Objective: Antenatal depression (AD) is the commonest morbidity during pregnancy. There is evidence that premenstrual syndrome (PMS) and AD share common immune-inflammatory and sex hormonal pathways. This study aims to evaluate the association between the severity of depressive PMS and AD in early and late pregnancy. Method: Participants were followed from early (<=16 weeks) to late pregnancy (>=20 weeks). The Premenstrual Symptoms Screening Tool (PSST) was used to assess PMS and AD symptoms were assessed using the Edinburgh Postnatal Depression Scale (EPDS). Results: Up to 57.6% of the variance in the early EPDS score was explained by the regression on the first factor extracted from 10 depression and anxiety PSST items (dubbed the DepAnx PSST), insomnia PSST, relation dissatisfaction, and partner abuse. There were specific indirect effects of DepAnx PSST (p < 0.001), insomnia PSST (p = 0.041), relation dissatisfaction (p = 0.023) and partner abuse (p = 0.007) on the late EPDS which were mediated by the early EPDS score. Conclusion: The affective, but not psychosomatic, symptoms of PMS strongly predict AD symptoms suggesting that the pathophysiology of affective PMS symptoms overlap with those of AD. (AU)


Assuntos
Humanos , Feminino , Gravidez , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Síndrome Pré-Menstrual , Depressão , Estresse Oxidativo , Tailândia , Escalas de Graduação Psiquiátrica , Inflamação
8.
FASEB J ; 37(3): e22792, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36723904

RESUMO

Cistanche tubulosa (Schrenk) Wight, named Guan hua Rou Cong-Rong in Chinese, is a traditional plant with liver, kidney, and intestine protective effects. Echinacoside (ECH) is its active constituent and has been found to have various biological effects, including antioxidative stress and anti-inflammatory effects. Liver injury caused by acetaminophen or CCL4 has been proven to benefit from ECH; however, the effects of ECH against alcoholic liver disease (ALD) remain unclear. This study was used to estimate the effect of echinacoside on nuclear factor erythroid 2-related factor 2 (Nrf2), which ameliorates ALD by inhibiting oxidative stress and cell apoptosis through affecting Nrf2.A mouse model of ALD was established with ethanol using hematoxylin and eosin (HE) staining, oiled staining, and biochemical indices. Alpha Mouse Liver 12 (AML-12) cells were induced with ethanol in vitro and analyzed using western blotting, flow cytometry, and biochemical assays. In the animal model of ALD, ECH dramatically reduced liver damage, as proven by the downregulation of aspartate aminotransferase (AST) and HE staining. In vitro, ECH distinctly reduced the damage caused by ethanol through the decreased expression of cleaved caspase-3 measured by western blotting. ECH significantly increased the activity of Nrf2 in vivo and in vitro. Nrf2 knockout may diminish the influence of ECH on ALD. Meanwhile, ECH also increased the expression of haem oxygenase-1 (HO-1) and glutamate-cysteine ligase catalytic subunit (GCLC), while it inhibited levels of oxidative stress and cell apoptosis. Our findings suggest that ECH protects against ethanol-induced liver injuries by alleviating oxidative stress and cell apoptosis by increasing the activity of Nrf2. Therefore, ECH is promising for the treatment of ALD.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Cistanche , Camundongos , Animais , Cistanche/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Fígado/metabolismo , Estresse Oxidativo , Etanol/toxicidade
9.
Am J Psychiatry ; 180(2): 127-138, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36722118

RESUMO

OBJECTIVE: Black Americans in the United States are disproportionately exposed to childhood adversity compared with White Americans. Such disparities may contribute to race-related differences in brain structures involved in regulating the emotional response to stress, such as the amygdala, hippocampus, and prefrontal cortex (PFC). The authors investigated neuroanatomical consequences of racial disparities in adversity. METHODS: The sample included 7,350 White American and 1,786 Black American children (ages 9-10) from the Adolescent Brain Cognitive Development Study (public data release 2.0). Structural MRI data, parent and child self-reports of adversity-related measures, and U.S. Census neighborhood data were used to investigate the relationship between racial disparities in adversity exposure and race-related differences in brain structure. RESULTS: Black children experienced more traumatic events, family conflict, and material hardship on average compared with White children, and their parents or caregivers had lower educational attainment, lower income, and more unemployment compared with those of White children. Black children showed lower amygdala, hippocampus, and PFC gray matter volumes compared with White children. The volumes of the PFC and amygdala, but not the hippocampus, also varied with metrics of childhood adversity, with income being the most common predictor of brain volume differences. Accounting for differences in childhood adversity attenuated the magnitude of some race-related differences in gray matter volume. CONCLUSIONS: The results suggest that disparities in childhood adversity contribute to race-related differences in gray matter volume in key brain regions associated with threat-related processes. Structural alterations of these regions are linked to cognitive-affective dysfunction observed in disorders such as posttraumatic stress disorder. More granular assessments of structural inequities across racial/ethnic identities are needed for a thorough understanding of their impact on the brain. Together, the present findings may provide insight into potential systemic contributors to disparate rates of psychiatric disease among Black and White individuals in the United States.


Assuntos
Encéfalo , Substância Cinzenta , Adolescente , Criança , Humanos , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Córtex Pré-Frontal , Córtex Cerebral , Emoções
10.
Neurobiol Dis ; 178: 106024, 2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36724860

RESUMO

Several studies identified noise-induced hearing loss (NIHL) as a risk factor for sensory aging and cognitive decline processes, including neurodegenerative diseases, such as dementia and age-related hearing loss (ARHL). Although the association between noise- and age-induced hearing impairment has been widely documented by epidemiological and experimental studies, the molecular mechanisms underlying this association are not fully understood as it is not known how these risk factors (aging and noise) can interact, affecting memory processes. We recently found that early noise exposure in an established animal model of ARHL (C57BL/6 mice) accelerates the onset of age-related cochlear dysfunctions. Here, we extended our previous data by investigating what happens in central brain structures (auditory cortex and hippocampus), to assess the relationship between hearing and memory impairment and the possible combined effect of noise and sensory aging on the cognitive domain. To this aim, we exposed juvenile C57BL/6 mice of 2 months of age to repeated noise sessions (60 min/day, pure tone of 100 dB SPL, 10 kHz, 10 consecutive days) and we monitored auditory threshold by measuring auditory brainstem responses (ABR), spatial working memory, by using the Y-maze test, and basal synaptic transmission by using ex vivo electrophysiological recordings, at different time points (1, 4 and 7 months after the onset of noise exposure, corresponding to 3, 6 and 9 months of age). We found that hearing loss, along with accelerated presbycusis onset, can induce persistent synaptic alterations in the auditory cortex. This was associated with decreased memory performance and oxidative-inflammatory injury in the hippocampus, the extra-auditory structure involved in memory processes. Collectively, our data confirm the critical relationship between auditory and memory circuits, suggesting that the combined detrimental effect of noise and sensory aging on hearing function can be considered a high-risk factor for both sensory and cognitive degenerative processes, given that early noise exposure accelerates presbycusis phenotype and induces hippocampal-dependent memory dysfunctions.

11.
J Photochem Photobiol B ; 240: 112654, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36724628

RESUMO

Long-term light exposure, especially in the spectrum of blue light, frequently causes excessive oxidative stress in dry age-related macular degeneration (AMD). Here, to gain insight into the underlying mechanism, we focused on mitochondrial dynamics alterations under long-term exposure to blue light in mouse and retinal cells. Six-month-old C57BL/6 mice were exposed to blue light (450 nm, 800 lx) for 2 weeks. The phenotypic changes in the retina were assayed using haematoxylin-eosin staining and transmission electron microscopy. Long-term blue light exposure significantly thinned each retinal layer in mice, induced retinal apoptosis and impaired retinal mitochondria. A retinal pigment epithelial cell line (ARPE-19) was used to verify the phototoxicity of blue light. Flow cytometry, immunofluorescence and MitoSox Red probe experiments confirmed that more total and mitochondria-specific ROS were generated in the blue light group than in the control group. Mito-Tracker Green probe showed fragmented mitochondrial morphology. The western blotting results indicated a significant increase in DRP1, OMA1, and BAX and a decrease in OPA1 and Bcl-2. In conclusion, long-term exposure to blue light damaged the retinas of mice, especially the ONL and RPE cells. There was destruction and dysfunction of mitochondria in RPE cells in vivo and in vitro. Mitochondrial dynamics were disrupted with characteristics of fusion-related obstruction after blue-light irradiation.

12.
Ecotoxicol Environ Saf ; 252: 114593, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36724708

RESUMO

Zinc, an essential trace mineral, plays a pivotal role in cell proliferation, maintenance of redox homeostasis, apoptosis, and aging. Serum zinc concentrations are reduced in patients with polycystic ovary syndrome (PCOS). However, the underlying mechanism of the effects of zinc deficiency on the female reproductive system, especially oocyte quality, has not been fully elucidated. Thus, we established an in vitro experimental model by adding N,N,N',N'-Tetrakis(2-pyridylmethyl) ethylenediamine (TPEN) into the culture medium, and to determine the potential regulatory function of zinc during porcine oocytes maturation. In the present study, we found that zinc deficiency caused aberrant meiotic progress, accompanied by the disrupted cytoskeleton structure in porcine oocytes. Zinc deficiency impaired mitochondrial function and dynamics, leading to the increase of reactive oxygen species (ROS) and acetylation level of the antioxidative enzyme superoxide dismutase 2 (SOD2), eventually induced the occurrence of oxidative stress and early apoptosis. Moreover, zinc deficiency perturbed cytosolic Ca2+ homeostasis, lipid droplets formation, demonstrating the aberrant mitochondrial function in porcine oocytes. Importantly, we found that zinc deficiency in porcine oocytes induced the occurrence of mitophagy by activating the PTEN-induced kinase 1/Parkin signaling pathway. Collectively, our findings demonstrated that zinc was a critical trace mineral for maintaining oocyte quality by regulating mitochondrial function and autophagy in porcine oocytes.

13.
Artigo em Inglês | MEDLINE | ID: mdl-36724838

RESUMO

The lipid-derived messenger oleoylethanolamide (OEA) has been involved in multiple physiological functions including metabolism and the immune response. More recently, OEA has been observed to affect reward-related behavior. Stress is a major risk factor for drug use and a predictor of drug relapse. In the laboratory, social stress has been largely studied using the social defeat (SD) model. Here, we explored the effects of different OEA administration schedules on the increased rewarding properties of cocaine induced by SD. In addition, we evaluated the anti-inflammatory action of OEA pretreatment in TLR4 expression caused by SD in the cerebellum, a novel brain structure that has been involved in the development of cocaine addiction. Adult OF1 mice were assigned to an experimental group according to the stress condition (exploration or SD) and treatment (OEA before SD, OEA before conditioning or subchronic OEA treatment). Mice were administered with OEA i.p (10 mg/kg) 10 min previously to the corresponding event. Three weeks after the last SD encounter, conditioned place preference (CPP) was induced by a subthreshold cocaine dose (1 mg/kg). As expected, socially defeated mice presented greater vulnerability to the cocaine reinforcing effects and expressed CPP. Conversely, this effect was not observed under a non-stressed condition. Most importantly, we observed that OEA pretreatment before SD or before conditioning prevented cocaine CPP in defeated mice. Biochemical analysis showed that OEA administration before SD decreased proinflammatory TLR4 upregulation in the cerebellum caused by social stress. In summary, our results suggest that OEA may have a protective effect on stress-induced increased cocaine sensitivity by exerting an anti-inflammatory action.

14.
BMC Med ; 21(1): 38, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726166

RESUMO

BACKGROUND: Cancer cells have developed molecular strategies to cope with evolutionary stressors in the dynamic tumor microenvironment. Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) is a metabolic rheostat that regulates diverse cellular adaptive behaviors, including growth and survival. However, the mechanistic role of PGC1α in regulating cancer cell viability under metabolic and genotoxic stress remains elusive. METHODS: We investigated the PGC1α-mediated survival mechanisms in metabolic stress (i.e., glucose deprivation-induced metabolic stress condition)-resistant cancer cells. We established glucose deprivation-induced metabolic stress-resistant cells (selected cells) from parental tumor cells and silenced or overexpressed PGC1α in selected and parental tumor cells. RESULTS: Several in vitro and in vivo mouse experiments were conducted to elucidate the contribution of PGC1α to cell viability in metabolic stress conditions. Interestingly, in the mouse xenograft model of patient-derived drug-resistant cancer cells, each group treated with an anti-cancer drug alone showed no drastic effects, whereas a group that was co-administered an anti-cancer drug and a specific PMCA inhibitor (caloxin or candidate 13) showed marked tumor shrinkage. CONCLUSIONS: Our results suggest that PGC1α is a key regulator of anti-apoptosis in metabolic and genotoxic stress-resistant cells, inducing PMCA expression and allowing survival in glucose-deprived conditions. We have discovered a novel therapeutic target candidate that could be employed for the treatment of patients with refractory cancers.


Assuntos
Neoplasias , Camundongos , Humanos , Animais , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Neoplasias/tratamento farmacológico , Estresse Fisiológico , Resistência a Medicamentos , Microambiente Tumoral
15.
J Psychiatr Res ; 159: 153-158, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36731380

RESUMO

Previous cross-sectional studies showed that COVID-19-related discrimination against healthcare workers was linked to depression. However, no study has examined the longitudinal association that allows causal interpretations. This prospective cohort study aimed to examine whether COVID-19-related discrimination at baseline is associated with depression and suicidal ideation several months later. Data were collected from October 2020 to July 2021. Multivariable logistic regression was performed. Fixed effects models were used to control for the effect of hospitals (Level 2 variable). Adjustments also included age, sex, living alone, alcohol consumption, exercise, BMI, working hours, comorbidity, and frontline worker status (Level 1 variables). Multiple sensitivity analyses were conducted to examine if the results substantially changed and were robust to unmeasured confounding. Multiple imputation for missing data was conducted via chained equations. As the final sample, 2862 healthcare workers without depression at baseline were studied. A total of 269 individuals (9.4%) experienced COVID-19-related discrimination. Depression was suggested in 205 participants (7.2%), and suicidal ideation in 108 participants (3.8%). In the adjusted models, COVID-19-related discrimination was significantly associated with subsequent depression (OR = 2.18, 95% CI = 1.39 to 2.90) and suicidal ideation (OR = 2.07, 95% CI = 1.22 to 3.50). Multiple sensitivity analyses verified the results. COVID-19-related discrimination results in depression and suicidal ideation in healthcare workers. Interventions to prevent such discrimination against healthcare workers, e.g., anti-discrimination campaigns, are crucial during the COVID-19 pandemic.

16.
Life Sci ; 317: 121461, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36731647

RESUMO

OBJECTIVES: Hepatic damage caused by oxidative stress is one of the problems associated with the emission of electromagnetic radiation (EMR). In this study, the effects of swimming exercise (SE) on oxidative stress and liver cell damage caused by EMR emission in rats were investigated. METHODS: Thirty-two rats (8 weeks old) were randomly divided into four groups, including control (C), EMR, SE, and EMR + SE. During four weeks, the animals engaged in SE (30 min/session, 5session/week) and were also exposed to EMR (4 h/day, seven days/week) emission from a Wi-Fi 2.45GHZ router. The liver and blood samples were collected at 48 h after completing four weeks of SE to assess histopathological damage, oxidative stress, and liver enzymes. KEY FINDINGS: Tissue sections showed severe liver damage in the EMR group compared to the C group, while the SE attenuated the liver damage. In the EMR group, compared to the C, SE and EMR + SE groups, the activity of superoxide dismutase (SOD) and catalase (CAT) decreased significantly, and the concentration of malondialdehyde (MDA) and liver enzymes (AST, ALT, and ALP) increased significantly (P < 0.05). Swimming exercise in the SE and EMR + SE groups compared to EMR led to a significant increase in the activity of SOD and CAT and a significant decrease in the concentration of MDA and liver enzymes (P < 0.05). CONCLUSION: The study findings showed that the SE is beneficial in attenuating the harmful effects of RF-EMR emitted from the Wi-Fi on the liver.

17.
Behav Brain Res ; 442: 114323, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36731657

RESUMO

Prolonged stress beginning in adolescence can contribute to the dysregulation of the neuroendocrine system in adulthood. As the neuroendocrine and neuroimmune systems participate in bi-directional regulatory control, adolescent stress can prime the neuroimmune system to future inflammatory insults. Previous work from our group demonstrates that stress exaggerates the hippocampal response to inflammation, which can lead to deficits in learning and memory. In the current study, we sought to interrogate the interaction between an acute peripheral challenge of lipopolysaccharide (LPS) in male and female Wistar rats with a history of stress beginning in adolescence (CAS). Males from the CAS group were more vulnerable to the peripheral effects of LPS compared to non-stressed males including porphyrin staining and ruffled fur. In contrast, LPS generated similar peripheral effects in females regardless of adolescent stress history. Learning and memory were differentially impacted by LPS as a function of stress history and effects manifested differently when stratified by sex. Males with a history of adolescent stress exhibited deficits in initial learning. Females from the CAS group performed similar to controls during acquisition but exhibited a slight impairment during reversal learning. Males and females with a history of stress displayed memory impairment during the probe assessments as compared to their same-sex control group. We conclude that while stress beginning in adolescence enhanced the vulnerability of learning and memory to an inflammatory challenge, the phenotype of this effect manifested differently in males and females. These data demonstrate a sustained impact of adolescent stress on the neuroimmune system which is sufficient to influence cognitive performance in both sexes.

18.
BMC Vet Res ; 19(1): 33, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36732758

RESUMO

BACKGROUND: Hypothyroidism is the most common endocrine disorder diagnosed in dogs, leading to deleterious effects on a dog's life quality. This study aims to evaluate changes in the redox status in canine hypothyroidism. For this purpose, a comprehensive panel of antioxidants and oxidants biomarkers were measured in serum and saliva of 23 dogs with hypothyroidism, 21 dogs with non-thyroidal illness, and 16 healthy dogs. Among the antioxidants, cupric reducing antioxidant capacity (CUPRAC), ferric reducing ability of plasma (FRAP), Trolox equivalent antioxidant capacity (TEAC), thiol, paraoxonase type 1 (PON-1) and glutathione peroxidase (GPx) were determined in serum and CUPRAC, ferric reducing ability of saliva (FRAS) and TEAC in saliva. The oxidant biomarkers included were total oxidant status (TOS), peroxide-activity (POX-Act), reactive oxygen-derived compounds (d-ROMs), advanced oxidation protein products (AOPP), and thiobarbituric acid reactive substances (TBARS) in serum and AOPP and TBARS in saliva. RESULTS: Results showed a significantly higher TEAC, PON-1, GPx, TOS, POX-Act, and d-ROMs, and a significantly lower AOPP in serum of dogs with hypothyroidism. Meanwhile, significantly lower FRAS and AOPP were observed in saliva of dogs with hypothyroidism. Once salivary concentrations were corrected based on their total protein concentrations, the only analyte showing significant changes was TBARS which was significantly higher in dogs with hypothyroidism. CONCLUSIONS: Our results show that dogs with hypothyroidism present alterations in the redox status in both serum and saliva. This study should be considered a preliminary study and further research addressing these changes should be made using larger populations.

19.
J Anim Sci Biotechnol ; 14(1): 22, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36732843

RESUMO

BACKGROUND: Zearalenone (ZEA) widely exists in moldy grains, which seriously destroys the fertility of females. Isorhamnetin, a natural flavonoid, has extensive of pharmacological activities. However, the beneficial effect and the underlying molecular mechanism of isorhamnetin involvement in ZEA-induced porcine oocyte damage have not been investigated. METHODS: Oocytes were treated with different concentrations of ZEA (3, 5, 8 and 10 µmol/L) and isorhamnetin (5, 10, 20 and 30 µmol/L) for 44 h at 39 â„ƒ. ZEA (5 µmol/L) and isorhamnetin (10 µmol/L) were selected for subsequent studies. Polar body exclusion rate, apoptosis rate and apoptosis related proteins, ROS levels and SOD2 protein, mitochondrial membrane potential and distribution, endoplasmic reticulum distribution and proteins expression, and PI3K, Akt and p-Akt proteins expression of oocytes were detected. In addition, the effect of PI3K antagonist (LY294002) on oocyte nuclear maturation and apoptosis were used to determine the involvement of PI3K/Akt signaling pathway. RESULTS: Our findings showed that ZEA exposure damaged oocytes and isorhamnetin therapy restored the developmental capability of porcine oocytes. Isorhamnetin promoted polar body extrusion rate to rescue ZEA-induced meiotic arrest in porcine oocytes. Isorhamnetin alleviated ZEA-induced oxidative stress by stimulating SOD2 protein expression and inhibiting ROS production. Moreover, isorhamnetin enhanced normal mitochondrial distribution and mitochondrial membrane potential to prevent mitochondrial dysfunction induced by ZEA. Changing the expression of endoplasmic reticulum stress-related marker proteins (CHOP, GRP78) and the distribution rate of normal endoplasmic reticulum showed that isorhamnetin relieved ZEA-caused endoplasmic reticulum stress. Mechanistically, isorhamnetin decreased Bax/Bcl-2 protein expression and inhibited ZEA-induced apoptosis through PI3K/Akt signaling pathway. CONCLUSIONS: Collectively, these results suggest that isorhamnetin protects oocytes from ZEA-caused damage through PI3K/Akt signaling pathway, which enhances meiotic maturation and mitochondrial function, and inhibits early apoptosis, oxidative stress and endoplasmic reticulum stress in porcine oocytes. Our study provides a new strategy for solving the reproductive toxicity induced by ZEA and treating woman infertility. A possible mechanism by which isorhamnetin protected porcine oocytes from ZEA-induced damage. Isorhamnetin inhibited meiosis arrest and apoptosis of porcine oocytes induced by ZEA through the PI3K/Akt signaling pathway. Moreover, isorhamnetin repaired ZEA-induced oocyte damage by alleviating oxidative stress, mitochondrial dysfunction and ER stress.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...