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1.
Sci Total Environ ; 949: 174958, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39067605

RESUMO

The aim of this study was to evaluate the sensitivity of the prawn Palaemon argentinus to the pyrethroid cypermethrin (CYP) and the tetramic acid spirotetramat (STM). These treatments were compared with prawns collected at a reference site to define their basal physiological state. Initially, physicochemical parameters and several pollutants at the selected site were analyzed. The LC50-96 h was determined in adult prawns. Then, prawns were exposed for 96 h to sublethal concentrations of CYP (0.0005 µg/l) and STM (0.44 mg/l) to evaluate the effects on some biochemical endpoints. A treatment combining both pesticides was also added at 5 % of these values. Controls with and without solvent (acetone) were included. The LC50-96 h values were 0.005 µg/l and 4.43 mg/l for CYP and STM, respectively. Moreover, some biomarkers linked to oxidative and energy metabolism were analyzed in the hepatopancreas and muscle of both essayed prawns and those at the basal state. The STM caused a significant decrease in total protein content (32 %) in contrast to the increase of protein carbonyl content (71 %) (p < 0.05). Also, glutathione S-transferase (52 %) and catalase (61 %) activities in the hepatopancreas of exposed prawns were higher compared to both the control and state basal groups (p < 0.05). In muscle, only a significant decrease in the lactate content (69 %) was caused by STM (p < 0.05). In addition, CYP caused a significant increase in the lactate dehydrogenase activity (110 %) in muscle and triacylglycerol content (73 %) in the hepatopancreas (p < 0.05). The integrated biomarker index (IBRv2) analysis showed that STM caused greater damage than CYP. Besides, the combined treatment showed an antagonistic interaction between both insecticides. The differential response of biomarkers to both CYP and STM exposure with respect to their basal levels shows a high sensitivity of P. argentinus demonstrating its potential role as a bioindicator organism.


Assuntos
Biomarcadores , Inseticidas , Palaemonidae , Piretrinas , Compostos de Espiro , Poluentes Químicos da Água , Animais , Palaemonidae/efeitos dos fármacos , Inseticidas/toxicidade , Piretrinas/toxicidade , Compostos de Espiro/toxicidade , Poluentes Químicos da Água/toxicidade , Biomarcadores/metabolismo , Compostos Aza/toxicidade , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo
2.
Meat Sci ; 216: 109557, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38852285

RESUMO

This study aimed to evaluate for the first time the temporal dynamic changes in early postmortem proteome of normal and high ultimate pH (pHu) beef samples from the same cattle using a shotgun proteomics approach. Ten selected carcasses classified as normal (pHu < 5.8; n = 5) or high (pHu ≥ 6.2; n = 5) pHu beef from pasture-finished Nellore (Bos taurus indicus) bulls were sampled from Longissimus thoracis muscle at 30 min, 9 h and 44 h postmortem for proteome comparison. The temporal proteomics profiling quantified 863 proteins, from which 251 were differentially abundant (DAPs) between high and normal pHu at 30 min (n = 33), 9 h (n = 181) and 44 h (n = 37). Among the myriad interconnected pathways regulating pH decline during postmortem metabolism, this study revealed the pivotal role of energy metabolism, cellular response to stress, oxidoreductase activity and muscle system process pathways throughout the early postmortem. Twenty-three proteins overlap among postmortem times and may be suggested as candidate biomarkers to the dark-cutting condition development. The study further evidenced for the first time the central role of ribosomal proteins and histones in the first minutes after animal bleeding. Moreover, this study revealed the disparity in the mechanisms underpinning the development of dark-cutting beef condition among postmortem times, emphasizing multiple dynamic changes in the muscle proteome. Therefore, this study revealed important insights regarding the temporal dynamic changes that occur in early postmortem of high and normal muscle pHu beef, proposing specific pathways to determine the biological mechanisms behind dark-cutting determination.


Assuntos
Músculo Esquelético , Proteoma , Carne Vermelha , Animais , Bovinos , Carne Vermelha/análise , Masculino , Concentração de Íons de Hidrogênio , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Proteínas Musculares/metabolismo , Proteômica/métodos , Mudanças Depois da Morte
3.
J Fish Biol ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38800844

RESUMO

The elucidation of energetic patterns in adult viviparous elasmobranchs and their offspring can contribute to understanding ecophysiological questions, such as maternal-fetal metabolism and group life-history traits. We characterized the energetic substrates in pregnant individuals and stages of offspring development in the freshwater stingray Potamotrygon amandae. Our results show that the energetic distribution of the yolk is composed of more lipids than proteins, whereas the inverse pattern is observed in the egg and uterus, proving the plasticity of the energy provision of the species. As a novelty, we describe that yolk/intestine transfer occurs in this species.

4.
Ann Hepatol ; 29(2): 101174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38579127

RESUMO

INTRODUCTION AND OBJECTIVES: Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease with a high prevalence worldwide and poses serious harm to human health. There is growing evidence suggesting that the administration of specific supplements or nutrients may slow NAFLD progression. Silymarin is a hepatoprotective extract of milk thistle, but its efficacy in NAFLD remains unclear. MATERIALS AND METHODS: Relevant studies were searched in PubMed, Embase, the Cochrane Library, Web of Science, clinicaltrails.gov, and China National Knowledge Infrastructure and were screened according to the eligibility criteria. Data were analyzed using Revman 5.3. Continuous values and dichotomous values were pooled using the standard mean difference (SMD) and odds ratio (OR). Heterogeneity was evaluated using the Cochran's Q test (I2 statistic). A P<0.05 was considered statistically significant. RESULTS: A total of 26 randomized controlled trials involving 2,375 patients were included in this study. Administration of silymarin significantly reduced the levels of TC (SMD[95%CI]=-0.85[-1.23, -0.47]), TG (SMD[95%CI]=-0.62[-1.14, -0.10]), LDL-C (SMD[95%CI]=-0.81[-1.31, -0.31]), FI (SMD[95%CI]=-0.59[-0.91, -0.28]) and HOMA-IR (SMD[95%CI]=-0.37[-0.77, 0.04]), and increased the level of HDL-C (SMD[95%CI]=0.46[0.03, 0.89]). In addition, silymarin attenuated liver injury as indicated by the decreased levels of ALT (SMD[95%CI]=-12.39[-19.69, -5.08]) and AST (SMD[95% CI]=-10.97[-15.51, -6.43]). The levels of fatty liver index (SMD[95%CI]=-6.64[-10.59, -2.69]) and fatty liver score (SMD[95%CI]=-0.51[-0.69, -0.33]) were also decreased. Liver histology of the intervention group revealed significantly improved hepatic steatosis (OR[95%CI]=3.25[1.80, 5.87]). CONCLUSIONS: Silymarin can regulate energy metabolism, attenuate liver damage, and improve liver histology in NAFLD patients. However, the effects of silymarin will need to be confirmed by further research.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Silimarina , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Silimarina/efeitos adversos , Testes de Função Hepática , Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Arch. argent. pediatr ; 122(2): e202310149, abr. 2024. ilus
Artigo em Inglês, Espanhol | LILACS, BINACIS | ID: biblio-1537741

RESUMO

La sepsis es un problema global de salud y la progresión hacia el shock séptico se asocia con un incremento marcado de la morbimortalidad. En este escenario, el aumento del lactato plasmático demostró ser un indicador de gravedad y un predictor de mortalidad, y suele interpretarse casi exclusivamente como marcador de baja perfusión tisular. Sin embargo, últimamente se produjo un cambio de paradigma en la exégesis del metabolismo y propiedades biológicas del lactato. En efecto, la adaptación metabólica al estrés, aun con adecuado aporte de oxígeno, puede justificar la elevación del lactato circulante. Asimismo, otras consecuencias fisiopatológicas de la sepsis, como la disfunción mitocondrial, se asocian con el desarrollo de hiperlactatemia sin que necesariamente se acompañen de baja perfusión tisular. Interpretar el origen y la función del lactato puede resultar de suma utilidad clínica en la sepsis, especialmente cuando sus niveles circulantes fundamentan las medidas de reanimación.


Sepsis is a global health problem; progression to septic shock is associated with a marked increase in morbidity and mortality. In this setting, increased plasma lactate levels demonstrated to be an indicator of severity and a predictor of mortality, and are usually interpreted almost exclusively as a marker of low tissue perfusion. However, a recent paradigm shift has occurred in the exegesis of lactate metabolism and its biological properties. Indeed, metabolic adaptation to stress, even with an adequate oxygen supply, may account for high circulating lactate levels. Likewise, other pathophysiological consequences of sepsis, such as mitochondrial dysfunction, are associated with the development of hyperlactatemia, which is not necessarily accompanied by low tissue perfusion. Interpreting the origin and function of lactate may be of great clinical utility in sepsis, especially when circulating lactate levels are the basis for resuscitative measures.


Assuntos
Humanos , Choque Séptico , Sepse/diagnóstico , Hiperlactatemia/complicações , Hiperlactatemia/etiologia , Ácido Láctico/metabolismo
7.
Mol Neurobiol ; 61(9): 6688-6707, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38340204

RESUMO

Stem cells possess extraordinary capacities for self-renewal and differentiation, making them highly valuable in regenerative medicine. Among these, neural stem cells (NSCs) play a fundamental role in neural development and repair processes. NSC characteristics and fate are intricately regulated by the microenvironment and intracellular signaling. Interestingly, metabolism plays a pivotal role in orchestrating the epigenome dynamics during neural differentiation, facilitating the transition from undifferentiated NSC to specialized neuronal and glial cell types. This intricate interplay between metabolism and the epigenome is essential for precisely regulating gene expression patterns and ensuring proper neural development. This review highlights the mechanisms behind metabolic regulation of NSC fate and their connections with epigenetic regulation to shape transcriptional programs of stemness and neural differentiation. A comprehensive understanding of these molecular gears appears fundamental for translational applications in regenerative medicine and personalized therapies for neurological conditions.


Assuntos
Diferenciação Celular , Epigênese Genética , Células-Tronco Neurais , Humanos , Animais , Diferenciação Celular/genética , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Neurogênese/genética
8.
Cell Stress Chaperones ; 29(1): 175-200, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38331164

RESUMO

The heat shock response (HSR) is an ancient and evolutionarily conserved mechanism designed to restore cellular homeostasis following proteotoxic challenges. However, it has become increasingly evident that disruptions in energy metabolism also trigger the HSR. This interplay between proteostasis and energy regulation is rooted in the fundamental need for ATP to fuel protein synthesis and repair, making the HSR an essential component of cellular energy management. Recent findings suggest that the origins of proteostasis-defending systems can be traced back over 3.6 billion years, aligning with the emergence of sugar kinases that optimized glycolysis around 3.594 billion years ago. This evolutionary connection is underscored by the spatial similarities between the nucleotide-binding domain of HSP70, the key player in protein chaperone machinery, and hexokinases. The HSR serves as a hub that integrates energy metabolism and resolution of inflammation, further highlighting its role in maintaining cellular homeostasis. Notably, 5'-adenosine monophosphate-activated protein kinase emerges as a central regulator, promoting the HSR during predominantly proteotoxic stress while suppressing it in response to predominantly metabolic stress. The complex relationship between 5'-adenosine monophosphate-activated protein kinase and the HSR is finely tuned, with paradoxical effects observed under different stress conditions. This delicate equilibrium, known as caloristasis, ensures that cellular homeostasis is maintained despite shifting environmental and intracellular conditions. Understanding the caloristatic controlling switch at the heart of this interplay is crucial. It offers insights into a wide range of conditions, including glycemic control, obesity, type 2 diabetes, cardiovascular and neurodegenerative diseases, reproductive abnormalities, and the optimization of exercise routines. These findings highlight the profound interconnectedness of proteostasis and energy metabolism in cellular function and adaptation.


Assuntos
Diabetes Mellitus Tipo 2 , Proteostase , Humanos , Proteínas de Choque Térmico HSP70/metabolismo , Resposta ao Choque Térmico , Monofosfato de Adenosina/metabolismo , Proteínas Quinases/metabolismo
9.
Mol Neurobiol ; 61(9): 6366-6382, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38296901

RESUMO

Obesity causes inflammation in the adipose tissue and can affect the central nervous system, leading to oxidative stress and mitochondrial dysfunction. Therefore, it becomes necessary to seek new therapeutic alternatives. Gold nanoparticles (GNPs) could take carnitine to the adipose tissue, thus increasing fatty acid oxidation, reducing inflammation, and, consequently, restoring brain homeostasis. The objective of this study was to investigate the effects of GNPs associated with carnitine on the neurochemical parameters of obesity-induced mice. Eighty male Swiss mice that received a normal lipid diet (control group) or a high-fat diet (obese group) for 10 weeks were used. At the end of the sixth week, the groups were divided for daily treatment with saline, GNPs (70 µg/kg), carnitine (500 mg/kg), or GNPs associated with carnitine, respectively. Body weight was monitored weekly. At the end of the tenth week, the animals were euthanized and the mesenteric fat removed and weighed; the brain structures were separated for biochemical analysis. It was found that obesity caused oxidative damage and mitochondrial dysfunction in brain structures. Treatment with GNPs isolated reduced oxidative stress in the hippocampus. Carnitine isolated decreased the accumulation of mesenteric fat and oxidative stress in the hippocampus. The combination of treatments reduced the accumulation of mesenteric fat and mitochondrial dysfunction in the striatum. Therefore, these treatments in isolation, become a promising option for the treatment of obesity.


Assuntos
Encéfalo , Carnitina , Modelos Animais de Doenças , Ouro , Nanopartículas Metálicas , Obesidade , Estresse Oxidativo , Animais , Carnitina/farmacologia , Carnitina/administração & dosagem , Carnitina/uso terapêutico , Ouro/farmacologia , Masculino , Obesidade/tratamento farmacológico , Obesidade/patologia , Obesidade/complicações , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Dieta Hiperlipídica , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/patologia , Lesões Encefálicas/metabolismo , Peso Corporal/efeitos dos fármacos
10.
Eur J Appl Physiol ; 124(6): 1835-1843, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38216723

RESUMO

PURPOSE: To examine the association of the single nucleotide polymorphism A1470T in the SLC16A1 gene with blood lactate accumulation during a graded exercise test and its associated metaboreflex. METHODS: Forty-six Latin-American men (Age: 27 ± 6 years; Body fat: 17.5 ± 4.7%) performed a graded exercise test on a treadmill for the assessment of maximal oxygen uptake (VO2max), lactate threshold (LT), ventilatory threshold (VT) and the exercise intensity corresponding to maximal fat oxidation rate (FATmax), via capillary blood samples and indirect calorimetry. Genomic DNA was extracted from a peripheral blood sample. Genotyping assay was carried out by real-time polymerase chain reaction to identify the A1470T polymorphism (rs1049434). RESULTS: Genotypes distribution were in Hardy-Weinberg equilibrium (X2 = 5.6, p > 0.05), observing allele frequencies of 0.47 and 0.53 for the A and T alleles, respectively. No difference in VO2max, body composition nor FATmax were observed across genotypes, whereas carriers of the TT genotype showed a higher LT (24.5 ± 2.2 vs. 15.6 ± 1.7 mL kg-1 min-1, p < 0.01) and VT in comparison to carriers of the AA + AT genotypes (32.5 ± 3.3 vs. 21.7 ± 1.5 mL kg-1 min-1, p < 0.01). Both, VO2max and the A1470T polymorphism were positively associated to the LT (R2 = 0.50, p < 0.01) and VT (R2 = 0.55, p < 0.01). Only VO2max was associated to FATmax (R2 = 0.39, p < 0.01). CONCLUSION: Independently of cardiorespiratory fitness, the A1470T polymorphism is associated to blood lactate accumulation and its associated ventilatory response during submaximal intensity exercise. However, the A1470 polymorphism does not influence fat oxidation capacity during exercise in young men.


Assuntos
Ácido Láctico , Transportadores de Ácidos Monocarboxílicos , Polimorfismo de Nucleotídeo Único , Simportadores , Humanos , Masculino , Adulto , Ácido Láctico/sangue , Simportadores/genética , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Consumo de Oxigênio/genética , Consumo de Oxigênio/fisiologia , Oxirredução , Teste de Esforço , Genótipo , Limiar Anaeróbio/genética , Limiar Anaeróbio/fisiologia , Exercício Físico/fisiologia , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia
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