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Autism spectrum disorder (ASD) is a psychiatric condition characterized by reduced social interaction, anxiety, and stereotypic behaviors related to neuroinflammation and microglia activation. We demonstrated that maternal exposure to Western diet (cafeteria diet or CAF) induced microglia activation, systemic proinflammatory profile, and ASD-like behavior in the offspring. Here, we aimed to identify the effect of alternate day fasting (ADF) as a non-pharmacologic strategy to modulate neuroinflammation and ASD-like behavior in the offspring prenatally exposed to CAF diet. We found that ADF increased plasma beta-hydroxybutyrate (BHB) levels in the offspring exposed to control and CAF diets but not in the cortex (Cx) and hippocampus (Hpp). We observed that ADF increased the CD45 + cells in Cx of both groups; In control individuals, ADF promoted accumulation of CD206 + microglia cells in choroid plexus (CP) and increased in CD45 + macrophages cells and lymphocytes in the Cx. Gestational exposure to CAF diet promoted defective sociability in the offspring; ADF improved social interaction and increased microglia CD206 + in the Hpp and microglia complexity in the dentate gyrus. Additionally, ADF led to attenuation of the ER stress markers (Bip/ATF6/p-JNK) in the Cx and Hpp. Finally, biological modeling showed that fasting promotes higher microglia complexity in Cx, which is related to improvement in social interaction, whereas in dentate gyrus sociability is correlated with less microglia complexity. These data suggest a contribution of intermittent fasting as a physiological stimulus capable of modulating microglia phenotype and complexity in the brain, and social interaction in male mice.
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Sertoli cells (SCs) are essential to maintaining germ cell development. Metformin, the main pharmacologic treatment for pediatric type 2 diabetes, is administered to children during SC maturation. The present study aimed to analyze whether metformin affects SC energy metabolism and blood-testis barrier (BTB) integrity. Primary SC cultures were used for the in vitro studies. In vivo effects were studied in Sprague-Dawley rats treated with 200 mg/kg metformin from Pnd14 to Pnd30. Metformin decreased fatty acid oxidation and increased 3-hydroxybutyrate production in vitro. Moreover, it decreased the transepithelial electrical resistance across the monolayer and induced ZO-1 redistribution, suggesting an alteration of cell junctions. In vivo, a mild but significant increase in BTB permeability and ZO-1 expression was observed in the metformin group, without changes in testicular histology and meiosis progression. Additionally, adult rats that received metformin treatment during the juvenile period showed no alteration in BTB permeability or daily sperm production. In conclusion, metformin exposure may affect BTB permeability in juvenile rats, but this seems not to influence spermatogenesis progression. Considering the results obtained in adult animals, it is possible to speculate that metformin treatment during the juvenile period does not affect testicular function in adulthood.
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The development of inexpensive and portable point-of-care devices for measuring nutritional physiological parameters from blood (e.g., glucose, ketones) has accelerated our understanding and assessment of real-time variation in human health, but these have infrequently been tested or implemented in wild animals, especially in relation to other key biological or fitness-related traits. Here we used point-of-care devices to measure blood levels of glucose, ketones, uric acid, and triglycerides in free-ranging house finches (Haemorhous mexicanus)-a common songbird in North America that has been well-studied in the context of urbanization, nutrition, health, and sexual selection-during winter and examined (1) repeatability of these methods for evaluating blood levels in these wild passerines, (2) intercorrelations among these measurements within individuals, (3) how blood nutritional-physiology metrics related to a bird's body condition, habitat of origin (urban vs. suburban), poxvirus infection, and sex; and (4) if the expression of male sexually selected plumage coloration was linked to any of the nutritional-physiological metrics. All blood-nutritional parameters were repeatable. Also, there was significant positive covariation between concentrations of circulating triglycerides and glucose and triglycerides and uric acid. Urban finches had higher blood glucose concentrations than suburban finches, and pox-infected individuals had lower blood triglyceride concentrations than uninfected ones. Last, redder males had higher blood glucose, but lower uric acid levels. These results demonstrate that point-of-care devices can be useful, inexpensive ways of measuring real-time variation in the nutritional physiology of wild birds.
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Tentilhões , Passeriformes , Infecções por Poxviridae , Humanos , Masculino , Animais , Tentilhões/fisiologia , Urbanização , Ácido Úrico/metabolismo , Glicemia , Sistemas Automatizados de Assistência Junto ao Leito , Animais Selvagens , Ecossistema , Fenômenos Fisiológicos da Nutrição , Cetonas/metabolismo , TriglicerídeosRESUMO
Ketogenic diets (KD) have been used in the treatment of epilepsy in humans for around a century and, more recently, they have been implanted for cancer patients, as well as in the treatment of obesity. This type of diet consists of high-fat levels, an adequate amount of protein and restricted carbohydrates, or high medium-chain triglycerides. Recently, the ketogenic diet has gained attention in veterinary medicine and studies were published evaluating the effects of KD in dogs with epilepsy. The objective of this review was to highlight recent studies about the application of KD in dogs and cats, to describe the neurobiochemical mechanisms through which KD improves epilepsy crisis, and their adverse effects. Studies were identified by a systematic review of literature available on PubMed, Embase, and Scopus. All cohort and case-control studies were included, and all articles were exported to Mendeley® citation manager, and duplicates were automatically removed. Seven articles and three conference abstracts conducted with dogs were included in the present study. There is evidence that the consumption of diets with medium-chain triglycerides increases the concentration of circulating ketone bodies and improves epilepsy signs, although these diets have higher carbohydrate and lower fat content when compared to the classic KD.
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Doenças do Gato , Dieta Cetogênica , Doenças do Cão , Epilepsia , Humanos , Gatos , Cães , Animais , Dieta Cetogênica/efeitos adversos , Dieta Cetogênica/veterinária , Epilepsia/veterinária , Triglicerídeos/metabolismoRESUMO
Background: Succinyl-CoA:3 oxoacid CoA transferase deficiency (SCOTD) is a rare autosomal recessive disease, characterized by altered utilization of ketone bodies, with acute episodes of ketoacidosis. Clinical case: It is presented the case of a patient with SCOTD, with a first atypical episode accompanied by hyperglycemia, with 4 subsequent episodes with classic manifestations of the disease, presenting with a biochemical pattern of permanent ketonuria with marked elevation of ketone bodies (acetoacetate, 3 beta-hydroxybutyrate) in the study of urinary organic acids by gas chromatography and mass spectrometry, together with the clinical picture granting the diagnosis. It was started a maintenance therapy with a characteristic feeding plan; it was shown an adequate response to treatment, and the absence of permanent ketosis was surmised. Conclusion: Being a rare disease, the categorization of these patients as diabetic ketoacidosis is frequent. The clinical and biochemical characteristics with ketosis or persistent ketonuria should be analyzed very carefully, especially in patients presenting with hyperglycemia, which is an atypical manifestation of the disease, in order to make an early diagnosis and treatment, positively impacting the prognosis of patients.
Introducción: la deficiencia de succinil-CoA acetoacetato transferasa (SCOT) es una enfermedad rara, autosómica recesiva, caracterizada por alteración en la utilización de cuerpos cetónicos, con episodios agudos de cetoacidosis. Caso clínico: se presenta el caso de un paciente con deficiencia de SCOT, con un primer episodio atípico acompañado con hiperglucemia, con 4 episodios posteriores con manifestaciones clásicas de la enfermedad, que presentó patrón bioquímico de cetonuria permanente con marcada elevación de cuerpos cetónicos (acetoacetato, 3 beta-hidroxibutirato) en estudio de ácidos orgánicos urinarios por cromatografía de gases y espectrometría de masas, aunado a cuadro clínico que otorgó el diagnóstico. Se inició terapia de mantenimiento con plan de alimentación característico; se demostró una adecuada respuesta al tratamiento, y se infirió una ausencia de cetosis permanente. Conclusiones: al ser una enfermedad rara, la categorización de estos pacientes como cetoacidosis diabética es frecuente. Se deben analizar de forma muy minuciosa las características clínicas y bioquímicas con cetosis o cetonuria persistente, sobre todo en pacientes que se presenten con hiperglucemia, que es una manifestación atípica de la enfermedad, para realizar un diagnóstico y tratamiento temprano que impacte de forma positiva el pronóstico de los pacientes.
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Hiperglicemia , Cetose , Humanos , Coenzima A-Transferases , Corpos Cetônicos , Cetose/etiologia , Ácido 3-Hidroxibutírico/análise , Hiperglicemia/complicaçõesRESUMO
This article reports on a patient who required a cranial protection system. Using additive manufacturing techniques and surgical planning with the help of bio-models, a patient-specific bone implant solution was proposed that allows aesthetic restoration of the affected area and provides an adequate level of protection. In addition, through a comparative analysis with finite elements, the mechanical response to external actions of the medical device, printed with two materials: polymethylmethacrylate (PMMA) and polyether-ether-ketone (PEEK), is simulated. The tested materials have recognized biocompatibility properties, but their costs on the market differ significantly. The results obtained demonstrate the similarities in the responses of both materials. It offers the possibility that low-income people can access these devices, guaranteeing adequate biomechanical safety, considering that PMMA is a much cheaper material than PEEK.
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A growing body of evidence supports the beneficial effects of the ketone bodies (KBs), acetoacetate and ß-hydroxybutyrate (BHB), on diverse physiological processes and diseases. Hence, KBs have been suggested as therapeutic tools for neurodegenerative diseases. KBs are an alternative fuel during fasting and starvation as they can be converted to Ac-CoA to produce ATP. A ketogenic diet (KD), enriched in fats and low in carbohydrates, induces KB production in the liver and favors their use in the brain. BHB is the most abundant KB in the circulation; in addition to its role as energy fuel, it exerts many actions that impact the set of proteins in the cell and tissue. BHB can covalently bind to proteins in lysine residues as a new post-translational modification (PTM) named ß-hydroxybutyrylation (Kbhb). Kbhb has been identified in many proteins where Kbhb sites can be critical for binding to other proteins or cofactors. Kbhb is mostly found in proteins involved in chromatin structure, DNA repair, regulation of spliceosome, transcription, and oxidative phosphorylation. Histones are the most studied family of proteins with this PTM, and H3K9bhb is the best studied histone mark. Their target genes are mainly related to cell metabolism, chromatin remodeling and the control of circadian rhythms. The role of Kbhb on physiological processes is poorly known, but it might link KB metabolism to cell signaling and genome regulation. BHB also impacts the proteome by influencing proteostasis. This KB can modulate the Unfolded Protein Response (UPR) and autophagy, two processes involved in the maintenance of protein homeostasis through the clearance of accumulated unfolded and damaged proteins. BHB can support proteostasis and regulate the UPR to promote metabolism adaptation in the liver and prevent cell damage in the brain. Also, BHB stimulates autophagy aiding to the degradation of accumulated proteins. Protein aggregation is common to proteinopathies like Alzheimer's (AD) and Parkinson's (PD) diseases, where the KD and BHB treatment have shown favorable effects. In the present review, the current literature supporting the effects of KBs on proteome conformation and proteostasis is discussed, as well as its possible impact on AD and PD.
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Sertoli cells (SCs) provide an adequate environment for germ cell development. SCs possess unique features that meet germ cells' metabolic demands: they produce lactate from glucose, which is delivered as energy substrate to germ cells. SCs store fatty acids (FAs) as triacylglycerols (TAGs) in lipid droplets (LDs) and can oxidize FAs to sustain their own energetic demands. They also produce ketone bodies from FAs. It has been shown that exposure of SCs to metabolic stresses, such as glucose deprivation, triggers specific adaptive responses that sustain cell survival and preserve lactate supply to germ cells. The aim of the present study was to investigate whether there are modifications in rat SCs lipid metabolism, including LD content, FA oxidation, and ketone bodies production, as part of their adaptive response to glucose deprivation. The present study was performed in 20-day-old rat SCs cultures. We determined LD content by Oil Red O staining, FA oxidation by measuring the release of 3 H2 O from [3 H] palmitate, TAGs and 3-hydroxybutyrate levels by spectrophotometric methods, and mRNA levels by RT-qPCR. Results show that the absence of glucose in SC culture medium entails: (1) a decrease in LD content and TAGs levels that is accompanied by decreased perilipin 1 mRNA levels, (2) an increase in FA oxidation that is in part mediated by AMP kinase (AMPK) activation and (3) a decrease in 3-hydroxybutyrate production. Additionally, we studied whether sestrins (SESN1, 2 and 3), proteins involved in the cellular response to stress, are regulated in glucose deprivation conditions. We show that there is an increase in SESN2 mRNA levels in deprived conditions. In conclusion, glucose deprivation affects SC lipid metabolism promoting FA mobilization from LDs to be used as energy source.
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Glucose , Células de Sertoli , Masculino , Ratos , Animais , Células de Sertoli/metabolismo , Glucose/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Adenilato Quinase , Metabolismo dos Lipídeos/genética , Ácido 3-Hidroxibutírico/metabolismo , Ácidos Graxos/metabolismo , RNA Mensageiro/genética , Corpos Cetônicos/metabolismo , LactatosRESUMO
Mitochondrial activity and quality control are essential for neuronal homeostasis as neurons rely on glucose oxidative metabolism. The ketone body, D-ß-hydroxybutyrate (D-BHB), is metabolized to acetyl-CoA in brain mitochondria and used as an energy fuel alternative to glucose. We have previously reported that D-BHB sustains ATP production and stimulates the autophagic flux under glucose deprivation in neurons; however, the effects of D-BHB on mitochondrial turnover under physiological conditions are still unknown. Sirtuins (SIRTs) are NAD+-activated protein deacetylases involved in the regulation of mitochondrial biogenesis and mitophagy through the activation of transcription factors FOXO1, FOXO3a, TFEB and PGC1α coactivator. Here, we aimed to investigate the effect of D-BHB on mitochondrial turnover in cultured neurons and the mechanisms involved. Results show that D-BHB increased mitochondrial membrane potential and regulated the NAD+/NADH ratio. D-BHB enhanced FOXO1, FOXO3a and PGC1α nuclear levels in an SIRT2-dependent manner and stimulated autophagy, mitophagy and mitochondrial biogenesis. These effects increased neuronal resistance to energy stress. D-BHB also stimulated the autophagic-lysosomal pathway through AMPK activation and TFEB-mediated lysosomal biogenesis. Upregulation of SIRT2, FOXOs, PGC1α and TFEB was confirmed in the brain of ketogenic diet (KD)-treated mice. Altogether, the results identify SIRT2, for the first time, as a target of D-BHB in neurons, which is involved in the regulation of autophagy/mitophagy and mitochondrial quality control.
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NAD , Sirtuína 2 , Animais , Camundongos , Ácido 3-Hidroxibutírico/farmacologia , Ácido 3-Hidroxibutírico/metabolismo , Autofagia , Glucose/metabolismo , Corpos Cetônicos/metabolismo , Corpos Cetônicos/farmacologia , Lisossomos/metabolismo , Mitocôndrias/metabolismo , NAD/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuína 2/metabolismoRESUMO
O trabalho foi realizado em uma fazenda de exploração leiteira em Castrolanda, no município de Castro PR. O sistema de manejo é free-stall, com 220 vacas da raça Holandesa com RHA305 de 6.740 litros. Foram coletadas amostras de sangue de 18 vacas de pré-parto, 4 dias antes da data prevista para o parto; e nos dias 4, 7 e 12 pós-parto, mediante punção venosa coccígea, utilizando-se SnapTest digital Ketovet®, constituindo 72 amostras, no período de fevereiro a maio de 2020. Em 4 vacas o BHB do sangue total apresentou-se acima do limite para cetose subclínica no quarto dia após o parto e 17 apresentaram-se acima do limite no sétimo dia, declinando em seguida, principalmente devido às intervenções clínicas. As médias e desvios-padrão foram: D - 4: 0,89 ± 0,257061; D 4: 1,05 ± 0,283279; D 7: 1,81 ± 0,456131; e D 12: 1,19 ± 0,437762. O benefício do monitoramento de BHB foi a imediata intervenção clínica, evitando-se a severidade por instalação de quadro clínico e as enfermidades concomitantes.(AU)
The study was carried out on a dairy farm in Castrolanda, in the county of Castro - PR. The management system is free stall, with 220 Holstein cows with RHA305 of 6,740 liters. Blood samples were collected from 18 pre-calving cows, 4 days before the expected date of calving; and on days 4, 7 and 12 postpartum, by means of coccygeal venipuncture, using SnapTest digital Ketovet®, constituting 72 samples, from February to May 2020. In 4 cows the BHB of whole blood was shown above the limit for subclinical ketosis on the fourth day after delivery and 17 presented above the limit on the seventh day, then declining mainly due to clinical interventions. The means and standard deviations were D -4: 0.89 ± 0.257061; D 4: 1.05 ± 0.283279; D 7: 1.81 ± 0.456131; and D 12: 1.19 ± 0.437762. The benefit of monitoring BHB was immediate clinical intervention, avoiding clinical ketosis and concomitant illnesses.(AU)
El estudio se realizó en una explotación lechera de Castrolanda, en la comarca de Castro - PR. El sistema de manejo es estabulación libre, con 220 vacas Holstein con RHA305 de 6.740 litros. Se recogieron muestras de sangre de 18 vacas pre- parto, 4 días antes de la fecha prevista de parto; y en los días 4, 7 y 12 postparto, mediante venopunción coccígea, utilizando SnapTest digital Ketovet®, constituyendo 72 muestras, desde febrero a mayo de 2020. En 4 vacas la BHB de sangre total se mostró por encima del límite para cetosis subclínica en el cuarto día después del parto y 17 presentaron por encima del límite en el séptimo día, disminuyendo después debido principalmente a intervenciones clínicas. Las medias y desviaciones estándar fueron D -4: 0,89 ± 0,257061; D 4: 1,05 ± 0,283279; D 7: 1,81 ± 0,456131; y D 12: 1,19 ± 0,437762. El beneficio de monitorizar la BHB fue la intervención clínica inmediata, evitando la cetosis clínica y las enfermedades concomitantes.(AU)
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Animais , Feminino , Bovinos/fisiologia , Corpos Cetônicos/análise , Cetose/diagnóstico , Diagnóstico PrecoceRESUMO
The liver has an essential role in responding to metabolic demands under stress conditions. The organ stores, releases, and recycles metabolism-related substrates. However, it is not clear how the Kallikrein-Kinin System modulates metabolic flexibility shift between energetic sources. AIMS: To analyze the hepatic metabolism in kinin B1 receptor deficient mice (B1KO mice) under fasting conditions. MAIN METHODS: WT and B1KO male mice were allocated in a calorimetric cage for 7 days and 48 h before the euthanasia, half of the animals of both groups were under fasting conditions. Biochemical parameters, ketone bodies (KB), and gene expression involving the liver energetic metabolism genes were evaluated. KEY FINDINGS: Kinin B1 receptor (B1R) modulates the metabolic shift under fasting conditions, reducing the VO2 expenditure. A preference for carbohydrates as an energetic source is suggested, as the B1KO group did not display an increase in KB in the serum. Moreover, the B1KO animals displayed higher serum triglycerides concentration compared to WT fasting mice. Interestingly, the lack of B1R induces the increase expression of enzymes from the glycolysis and lipolysis pathways under the fed. However, under fasting, the enzymatic expression of gluconeogenesis, glyceroneogenesis, and ketogenesis of these pathways does not occur, suggesting an absence of the shift metabolism responsivity, and this condition is modulated by PDK4 under FOXO1 control. SIGNIFICANCE: B1R has an important role in the hepatic glucose metabolism, which in turn influences the energetic metabolism, and in long-term outcomes, such as in the decrease in hepatic glycogen stores and in the enhancement of hepatic metabolism.
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Jejum , Gluconeogênese , Lipogênese , Fígado/metabolismo , Receptor B1 da Bradicinina/fisiologia , Estresse Fisiológico , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
Differently modified Lipozyme 435 (L435) (immobilized lipase B from Candida antarctica) preparations were used as biocatalysts in the esterification reaction to synthesize sugar fatty acid esters (SFAEs) from xylose (acyl acceptor) and lauric/palmitic acids (acyl donors) in methyl ethyl ketone (MEK) solvent. The L435 treatment with polyethyleneimine (PEI) (2; 25; and 750 KDa) prevented the enzyme leakage in the crude sugar ester reaction product. The 2 KDa PEI coating of this enzyme preparation produced the highest enzyme stability in MEK, buffer solutions (pHs 5 and 7), and methanol aqueous phosphate buffer at pH 7. Using an excess of the acyl donor (1:5 xylose: fatty acid molar ratio), high xylose conversions (70-84%) were obtained after 24 h-reaction using both, non-modified and PEI (2 KDa) coated L435, but the PEI treated biocatalyst afforded a higher xylose modification degree. After 5 reuse cycles with the L435 coated with PEI 2 KDa, the xylose conversions only decreased 10%, while with the non-treated biocatalyst they decreased by 37%. The formation of SFAEs was confirmed by mass spectrometry, which showed the presence of xylose mono-, di-, and triesters. They exhibited emulsion capacities close to that of a commercial sucrose monolaurate.
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Materiais Revestidos Biocompatíveis/química , Ésteres/química , Ácidos Graxos/química , Lipase/química , Polietilenoimina/química , Xilose/química , Biocatálise , Emulsões , Ativação Enzimática , Estabilidade Enzimática , Ésteres/síntese química , Hidrólise , Especificidade por SubstratoRESUMO
In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of substrates' molar ratios, reaction temperature, reaction time on esterification rates, and Lipozyme 435 reuse were studied. Results showed that an excess of oleic acid (xylose: oleic acid molar ratio of 1:5) significantly favored the reaction, yielding 98% of xylose conversion and 31% oleic acid conversion after 24 h-reaction (mainly to xylose mono- and dioleate, as confirmed by mass spectrometry). The highest Lipozyme 435 activities occurred between 55 and 70 °C. The predicted Ping Pong Bi Bi kinetic model fitted very well to the experimental data and there was no evidence of inhibitions in the range assessed. The reaction product was purified and presented an emulsion capacity close to that of a commercial sugar ester detergent. Finally, the repeated use of Lipozyme 435 showed a reduction in the reaction yields (by 48 and 19% in the xylose and oleic acid conversions, respectively), after ten 12 h-cycles.
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Butanonas/química , Lipase/metabolismo , Xilose/química , Biocatálise , Esterificação , Temperatura Alta , Ácido Oleico/químicaRESUMO
It is well known that a small number of graphene nanoparticles embedded in polymers enhance the electrical conductivity; the polymer changes from being an insulator to a conductor. The graphene nanoparticles induce several quantum effects, non-covalent interactions, so the percolation threshold is accelerated. We studied five of the most widely used polymers embedded with graphene nanoparticles: polystyrene, polyethylene-terephthalate, polyether-ketone, polypropylene, and polyurethane. The polymers with aromatic rings are affected mainly by the graphene nanoparticles due to the π-π stacking, and the long-range terms of the dispersion corrections are predominant. The polymers with linear structure have a CH-π stacking, and the short-range terms of the dispersion corrections are the important ones. We used the action radius as a measuring tool to quantify the non-covalent interactions. This action radius was the main parameter used in the Monte-Carlo simulation to obtain the conductivity at room temperature (300 K). The action radius was the key tool to describe how the percolation transition works from the fundamental quantum levels and connect the microscopic study with macroscopic properties. In the Monte-Carlo simulation, it was observed that the non-covalent interactions affect the electronic transmission, inducing a higher mean-free path that promotes the efficiency in the transmission.
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Resumen En Patología Forense es común estudiar cadáveres de individuos con antecedente de alcoholismo crónico, que son encontrados fallecidos y cuyo deceso no fue presenciado; por lo que en gran cantidad de autopsias la determinación de la causa de muerte es compleja. La cetoacidosis alcohólica constituye un síndrome complejo derivado de una alteración del metabolismo en el contexto de un consumo excesivo de alcohol e ingesta calórica insuficiente. Se trata de un diagnóstico diferencial importante como causa de muerte en alcohólicos crónicos que fallecen posterior a un ayuno de algunos días, secundario a molestias abdominales como gastritis inducida por etanol, usualmente asociada a vómitos. Clínicamente estas personas presentan además dolor abdominal, taquicardia y alteraciones respiratorias. El diagnóstico postmortem se confirma mediante la presencia de cuerpos cetónicos, especialmente beta-hidroxibutirato, en sangre, humor vítreo u orina. A continuación se presentan tres casos de muerte súbita por cetoacidosis alcohólica con historia de abuso crónico de bebidas etílicas; se discute su fisiopatología, hallazgos al momento de la autopsia y resultados de exámenes complementarios (análisis toxicológico y estudio histopatológico).
Abstract In the forensic pathology setting, it is frequent to study corpses of individuals that were known to be chronic alcoholics and suffered a sudden death. Therefore, many autopsies are performed, in which determining the cause of death is a complex task. Alcoholic ketoacidosis refers to a complex syndrome derived from a metabolic disarrangement, related to excessive consumption of alcohol and an insufficient caloric intake. It is an important diagnosis that should be considered in sudden deaths of chronic alcoholics with a recent history of fasting, due to abdominal complains such as gastritis induced by alcohol and usually associated with recurrent vomiting. Clinically these patients present with abdominal pain, tachycardia and respiratory anomalies. The diagnosis can be confirmed when elevated ketone bodies, especially beta-hydroxybutyrate, are found in blood, vitreous humour or urine. In this paper we present three cases of sudden death by alcoholic ketoacidosis with a history of chronic abuse of alcohol, discussing it´s pathophysiology, autopsy findings and the results of additional studies (toxicologic screening and histopathology).
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Autopsia , Corpos Cetônicos , Cetose/diagnóstico , Costa RicaRESUMO
Glucose supply from blood is mandatory for brain functioning and its interruption during acute hypoglycemia or cerebral ischemia leads to brain injury. Alternative substrates to glucose such as the ketone bodies (KB), acetoacetate (AcAc), and ß-hydroxybutyrate (BHB), can be used as energy fuels in the brain during hypoglycemia and prevent neuronal death, but the mechanisms involved are still not well understood. During glucose deprivation adaptive cell responses can be activated such as autophagy, a lysosomal-dependent degradation process, to support cell survival. However, impaired or excessive autophagy can lead to cell dysfunction. We have previously shown that impaired autophagy contributes to neuronal death induced by glucose deprivation in cortical neurons and that D isomer of BHB (D-BHB) reestablishes the autophagic flux increasing viability. Here, we aimed to investigate autophagy dynamics in the brain of rats subjected to severe hypoglycemia (SH) without glucose infusion (GI), severe hypoglycemia followed by GI (SH + GI), and a brief period of hypoglycemic coma followed by GI (Coma). The effect of D-BHB administration after the coma was also tested (Coma + BHB). The transformation of LC3-I to LC3-II and the abundance of autophagy proteins, Beclin 1 (BECN1), ATG7, and ATG12-ATG5 conjugate, were analyzed as an index of autophagosome formation, and the levels of sequestrosome1/p62 (SQSTM1/p62) were determined as a hallmark of autophagic degradation. Data suggest that autophagosomes accumulate in the cortex and the hippocampus of rats after SH, likely due to impaired autophagic degradation. In the cortex, autophagosome accumulation persisted at 6 h after GI in animals exposed to SH but recovered basal levels at 24 h, while in the hippocampus no significant effect was observed. In animals subjected to coma, autophagosome accumulation was observed at 24 h after GI in both regions. D-BHB treatment reduced LC3-II and SQSTM1/p62 content and reduced ULK1 phosphorylation by AMPK, suggesting it stimulates the autophagic flux and decreases AMPK activity reducing autophagy initiation. D-BHB also reduced the number of degenerating cells. Together, data suggest different autophagy dynamics after GI in rats subjected to SH or the hypoglycemic coma and support that D-BHB treatment can modulate autophagy dynamics favoring the autophagic flux.
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Polyether-ether-ketone (PEEK) has emerged in Implant Dentistry with a series of short-time applications and as a promising material to substitute definitive dental implants. Several strategies have been investigated to diminish biofilm formation on the PEEK surface aiming to decrease the possibility of related infections. Therefore, a comprehensive review was carried out in order to compare PEEK with materials widely used nowadays in Implant Dentistry, such as titanium and zirconia, placing emphasis on studies investigating its ability to grant or prevent biofilm formation. Most studies failed to reveal significant antimicrobial activity in pure PEEK, while several studies described new strategies to reduce biofilm formation and bacterial colonization on this material. Those include the PEEK sulfonation process, incorporation of therapeutic and bioactive agents in PEEK matrix or on PEEK surface, PEEK coatings and incorporation of reinforcement agents, in order to produce nanocomposites or blends. The two most analyzed surface properties were contact angle and roughness, while the most studied bacteria were Escherichia coli and Staphylococcus aureus. Despite PEEK's susceptibility to biofilm formation, a great number of strategies discussed in this study were able to improve its antibiofilm and antimicrobial properties.
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ß-hydroxybutyrate is the main ketone body generated by the liver under starvation. Under these conditions, it can sustain ATP levels by its oxidation in mitochondria. As mitochondria can modify its shape and function under different nutritional challenges, we study the chronic effects of ß-hydroxybutyrate supplementation on mitochondrial morphology and function, and its relation to exercise capacity. Male C57BL/6 mice were supplemented with ß-hydroxybutyrate mineral salt (3.2%) or control (CT, NaCl/KCl) for six weeks and submitted to a weekly exercise performance test. We found an increase in distance, maximal speed, and time to exhaustion at two weeks of supplementation. Fatty acid metabolism and OXPHOS subunit proteins declined at two weeks in soleus but not in tibialis anterior muscles. Oxygen consumption rate on permeabilized fibers indicated a decrease in the presence of pyruvate in the short-term treatment. Both the tibialis anterior and soleus showed decreased levels of Mitofusin 2, while electron microscopy assessment revealed a significant reduction in mitochondrial cristae shape in the tibialis anterior, while a reduction in the mitochondrial number was observed only in soleus. These results suggest that short, but not long-term, ßhydroxybutyrate supplementation increases exercise capacity, associated with modifications in mitochondrial morphology and function in mouse skeletal muscle.
Assuntos
Ácido 3-Hidroxibutírico/administração & dosagem , Suplementos Nutricionais , Tolerância ao Exercício/efeitos dos fármacos , Mitocôndrias Musculares/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Animais , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacosRESUMO
RESUMEN La hipercetonemia o cetosis bovina es un desorden metabólico, que se caracteriza por el incremento patológico de cuerpos cetónicos (beta-hidroxibutirato (βHB), Acetoacetato (AcAc) y acetona) y ocurre en el periparto de vacas de leche. El origen primario de la enfermedad es el balance energético negativo (BEN), que puede ser desencadenado por el incremento excesivo de los requerimientos energéticos o la presentación de enfermedades posparto, resultando en la presentación de signos clínicos o disminución de la producción de leche. El objetivo de esta revisión consiste en describir, mediante un modelo, los procesos bioquímicos del rumen y los mecanismos fisiopatológicos, involucrados con incremento excesivo de los cuerpos cetónicos. En resumen, se realizó un modelo fisiológico uniendo literatura fragmentada, sobre la relación entre la función ruminal, hepática y la inducción de lipolisis e incremento de la actividad de Carnitil-Palmitoil transferasa-1 (CPT-1), cuyo resultado puede ser la producción excesiva de Acetil-CoA que, junto con la falta de propionato y oxalacetato (precursores de gluconeogénesis y ciclo de Krebs), dan lugar a la producción patológica de acetoacetato y beta-hidroxibutirato.
ABSTRACT Bovine hyperketonemia or ketosis is a metabolic disorder characterized by high levels of ketone bodies (beta-hydroxybutyrate (βHB), Acetoacetate (AcAc), and acetone) in periparturient dairy cows. A Negative Energy Balance (NEB) is identified as the primary cause of the disease, which is triggered by the excessive increase of energy requirements or the presence of postpartum diseases, resulting in the appearance of clinical signs or decreased milk production. The purpose of this review is to describe the rumen's biochemical Process and the physiopathological mechanisms involved in the excessive production of ketone bodies. After conducting a literature review, a physiological model was carried out in order to understand the relationship between the rumen and liver functions with lipolysis induction and increased CPT-1 activity. The above may result in the overproduction of Acetyl-CoA, which together, with the lack of propionate and oxaloacetate (gluconeogenesis and Krebs cycle precursors), leads to the pathological production of acetoacetate and beta-hydroxybutyrate.
RESUMO
BACKGROUND: The end of pregnancy is the period with the highest risk of occurrences of ketosis and pregnancy toxemia due to fat mobilization and increasing non-esterified fatty acids in the liver which are converted in ketone bodies, mainly ß-hydroxybutyrate acid (BHB). This ketone body may also become elevated in the bloodstream. The present study validates the use of a handheld meter for determining the blood concentration of BHB and ascertaining the predictive value and accuracy of BHB measurements in diagnosing hyperketonaemia in ewes. METHODS: A total of 19, non-pregnant, crossbred ewes were subjected to 2 h of intravenous infusion of a saturated BHB solution. Over 6 h of evaluation, 247 blood samples were obtained in 13 sampling moments. The BHB concentration was measured by an enzymatic colorimetric method in an automated biochemical analyzer (gold-standard) and by a handheld meter using an electrochemical enzyme technique. RESULTS: There was a high correlation between both methods (r = 0.98; P < 0.001). Considering the blood BHB concentrations range 0.8-1.6 mmol/L for moderate ketosis the handheld meter presented sensitivity and specificity of 0.98 and 0.81, respectively. For severe ketosis (BHB ≥ 1.6 mmol/L) sensitivity and specificity were 0.99 and 0.75, respectively. Thus, the handheld device can be useful for diagnoses of cases of mild or severe pregnancy toxemia at field conditions.