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RESUMEN Introducción: la dexametasona es un medicamento que demostró una disminución de la mortalidad en la neumonía por SARS-CoV-2. Se desconoce la utilidad de otros corticoides, dosis y su duración para mejorar este resultado clínico. Objetivo: comparar la mortalidad de los pacientes adultos con neumonía por SARS-CoV-2 tratados con dexametasona versus metilprednisolona en el Hospital Nacional, Itauguá, Paraguay. Materiales y métodos: estudio ambispectivo. Se incluyeron 97 pacientes, 52 recibieron dexametasona y 45 metilprednisolona. Se utilizó un muestreo no probabilístico de casos consecutivos. Las variables fueron sometidas a estadística descriptiva y analítica. El protocolo fue aprobado por el Comité de Ética del Hospital Nacional. Los autores no presentan conflictos de interés. Resultados: todos los pacientes ingresaron con neumonía con valoración de 4 (OMS). No se encontraron diferencias significativas en la mortalidad entre ambos grupos. Al aplicar un análisis estratificado por edad, en los pacientes <65 años la mortalidad en los que recibieron dexametasona fue 15,8% mientras que los que recibieron metilprednisolona no fallecieron (p 0,03). En el grupo de ≥65 años la mortalidad n los recibieron dexametasona fue 29,4% vs. 21,4% en los que recibieron metilprednisolona (p 0,7). Conclusiones: en los pacientes <65 años tratados con dexametasona la mortalidad fue mucho más alta que en los que recibieron metilprednisolona, ya que en este último grupo no se registraron fallecimientos.
ABSTRACT Introduction: Dexamethasone is a medication that demonstrated a decrease in mortality in SARS-CoV-2 pneumonia. The usefulness of other corticosteroids, dose and their duration to improve this clinical result is unknown. Objective: To compare the mortality of adult patients with SARS-CoV-2 pneumonia treated with dexamethasone versus methylprednisolone at the Hospital Nacional of Itauguá, Paraguay. Materials and Methods: Ambispective study. Ninety seven patients were included, 52 received dexamethasone and 45 methylprednisolone. A non-probabilistic sampling of consecutive cases was used. The variables were subjected to descriptive and analytical statistics. The protocol was approved by the Ethics Committee of the Hospital Nacional. The authors do not present conflicts of interest. Results: All patients entered with 4 (WHO) vaulting pneumonia. No significant differences were found in mortality between both groups. When applying an age stratified analysis, in patients <65 years who received dexamethasone the mortality was 15.8% while those who received methylprednisolone did not die (p 0.03). In the ≥65 years group, mortality in those who received dexamethasone was 29.4% vs. 21.4% in those who received methylprednisolone (p 0.7). Conclusions: In patients <65 years treated with dexamethasone, mortality was much higher than in those who received methylprednisolone, since in the latter group no deaths were recorded.
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Food additives are compounds used in order to improve food palatability, texture, and shelf life. Despite a significant effort to assure safety of use, toxicological analysis of these substances, generally, rely on their direct toxicity to target organs (liver and kidney) or their genotoxic effects. Much less attention is paid to the effects of these compounds on cells of the immune system. This is of relevance given that metabolic dysregulation and obesity have a strong immune-mediated component. Obese individuals present a state of chronic low-grade inflammation that contributes to the establishment of insulin resistance and other metabolic abnormalities known as the metabolic syndrome. Obesity and metabolic syndrome are currently recognized as worldwide epidemics that pose a profound socioeconomic impact and represent a concern to public health. Cells of the immune system contribute to both the maintenance of "lean homeostasis" and the metabolic dysregulation observed in obese individuals. Although much attention has been drawn in the past decades to obesity and metabolic syndrome as a result of ingesting highly processed food containing large amounts of fat and simple sugars, mounting evidence suggest that food additives may also be important contributors to metabolic derangement. Herein, we review pieces of evidence from the literature showing that food additives have relevant effects on cells of the immune system that could contribute to immune-mediated metabolic dysregulation. Considering their potential to predispose individuals to develop obesity and metabolic syndrome, their use should be taken with caution or maybe revisited.
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Overweight and obesity have become epidemic worldwide and are linked to sedentary lifestyle and the consumption of processed foods and drinks. Citrate is a metabolite that plays central roles in carbohydrate and lipid metabolism. In addition, citrate is the additive most commonly used by the food industry, and therefore is highly consumed. Extracellular citrate can freely enter the cells via the constitutively expressed plasma membrane citrate transporter. Within the cytosol, citrate is readily metabolised by ATP-citrate lyase into acetyl-CoA - the metabolic precursor of endogenously produced lipids and cholesterol. We therefore hypothesised that the citrate ingested from processed foods and drinks could contribute to increased postprandial fat production and weight gain. To test our hypothesis, we administered citrate to mice through their drinking water with or without sucrose and monitored their weight gain and other metabolic parameters. Our results showed that mice receiving citrate or citrate+sucrose did not show increased weight gain or an increase in the weight of the liver, skeletal muscles or adipose tissues (AT). Moreover, the plasma lipid profiles (TAG, total cholesterol, LDL and HDL) were similar across all groups. However, the group receiving citrate+sucrose showed augmented fasting glycaemia, glucose intolerance and the expression of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6 and IL-10) in their AT. Therefore, our results suggest that citrate consumption contributes to increased AT inflammation and altered glucose metabolism, which is indicative of initial insulin resistance. Thus, citrate consumption could be a previously unknown causative agent for the complications associated with obesity.
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Ácido Cítrico/efeitos adversos , Sacarose Alimentar/efeitos adversos , Aditivos Alimentares/efeitos adversos , Intolerância à Glucose/etiologia , Resistência à Insulina , Gordura Intra-Abdominal/imunologia , Paniculite/etiologia , Animais , Citocinas/sangue , Dieta Ocidental/efeitos adversos , Intolerância à Glucose/imunologia , Intolerância à Glucose/metabolismo , Intolerância à Glucose/patologia , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/patologia , Lipídeos/sangue , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Tamanho do Órgão , Paniculite/imunologia , Paniculite/metabolismo , Paniculite/patologia , Distribuição AleatóriaRESUMO
Mycobacterium leprae, the intracellular etiological agent of leprosy, infects Schwann promoting irreversible physical disabilities and deformities. These cells are responsible for myelination and maintenance of axonal energy metabolism through export of metabolites, such as lactate and pyruvate. In the present work, we observed that infected Schwann cells increase glucose uptake with a concomitant increase in glucose-6-phosphate dehydrogenase (G6PDH) activity, the key enzyme of the oxidative pentose pathway. We also observed a mitochondria shutdown in infected cells and mitochondrial swelling in pure neural leprosy nerves. The classic Warburg effect described in macrophages infected by Mycobacterium avium was not observed in our model, which presented a drastic reduction in lactate generation and release by infected Schwann cells. This effect was followed by a decrease in lactate dehydrogenase isoform M (LDH-M) activity and an increase in cellular protection against hydrogen peroxide insult in a pentose phosphate pathway and GSH-dependent manner. M. leprae infection success was also dependent of the glutathione antioxidant system and its main reducing power source, the pentose pathway, as demonstrated by a 50 and 70% drop in intracellular viability after treatment with the GSH synthesis inhibitor buthionine sulfoximine, and aminonicotinamide (6-ANAM), an inhibitor of G6PDH 6-ANAM, respectively. We concluded that M. leprae could modulate host cell glucose metabolism to increase the cellular reducing power generation, facilitating glutathione regeneration and consequently free-radical control. The impact of this regulation in leprosy neuropathy is discussed.
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Humanos , Células de Schwann/metabolismo , Células de Schwann/microbiologia , Hanseníase Tuberculoide/metabolismo , Linhagem Celular , Ácido Láctico/metabolismo , Metabolismo Energético , Glucose/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Metionina/análogos & derivados , Metionina/farmacologia , Mitocôndrias/metabolismo , Mycobacterium leprae/metabolismoRESUMO
Cancer cells are highly dependent on glycolysis to supply the energy and intermediates required for cell growth and proliferation. The enzyme 6-phosphofructo-1-kinase (PFK) is critical for glycolysis, and its activity is directly correlated with cellular glucose consumption. Resveratrol is a potential anti-tumoral drug that decreases glucose metabolism and viability in cancer cells. However, the mechanism involved in resveratrol-mediated anti-tumor activity is not entirely clear. In this work, it is demonstrated that resveratrol decreases viability, glucose consumption and ATP content in the human breast cancer cell line MCF-7. These effects are directly correlated with PFK inhibition by resveratrol in these cells. Moreover, resveratrol directly inhibits purified PFK, promoting the dissociation of the enzyme from fully active tetramers into less active dimers. This effect is exacerbated by known negative regulators of the enzyme, such as ATP and citrate. On the other hand, positive modulators that stabilize the tetrameric form of the enzyme, such as fructose-2,6-bisphosphate and ADP, prevent the inhibition of PFK activity by resveratrol, an effect not observed with increased pH. In summary, our results provide evidence that resveratrol directly inhibits PFK activity, therefore disrupting glucose metabolism and reducing viability in cancer cells.
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Antioxidantes/farmacologia , Neoplasias da Mama/metabolismo , Glucose/metabolismo , Fosfofrutoquinase-1/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Estilbenos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , ResveratrolRESUMO
The present work describes the effects of metformin on hexokinase (HK) and phosphofructokinase (PFK) activities and localization in different tissues from streptozotocin-induced diabetic mice. Diabetic mice present lower HK and PFK activities (50%) in skeletal muscle, liver and adipose tissue, as compared with control (P<0.05). Treatment with 250 mg/kg metformin reverses this pattern of enzyme inhibition with concomitant reversal of hyperglycemia and hypolactacidemia. Furthermore, the treatment increases the cytoskeleton-associated PFK activity in skeletal muscle; this activity has been described as an important mechanism for the enzyme activation. This effect might be due to the increased phosphorylation of serine residues in the enzyme, a modification which has been described to increase the interaction of PFK with f-actin. The current work supports the hypothesis that metformin hypoglycemic effects involve the activation of glycolysis through its regulatory enzymes, which may be potential targets for the development of new hypoglycemic drugs.
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Tecido Adiposo/efeitos dos fármacos , Diabetes Mellitus Experimental/enzimologia , Hexoquinase/metabolismo , Fígado/efeitos dos fármacos , Metformina/farmacologia , Músculo Esquelético/efeitos dos fármacos , Fosfofrutoquinase-1/metabolismo , Tecido Adiposo/metabolismo , Animais , Biocatálise/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Desenho de Fármacos , Glicólise/efeitos dos fármacos , Hipoglicemia/tratamento farmacológico , Fígado/metabolismo , Masculino , Metformina/uso terapêutico , Camundongos , Músculo Esquelético/metabolismo , Fosforilação/efeitos dos fármacosRESUMO
Esta revisión bibliográfica tiene como propósito exponer la relación que se ha encontrado entre la enfermedad periodontal y algunas alteraciones del embarazo como la preeclampsia, el retardo en el crecimiento fetal, la ruptura prematura de membranas, el parto a pretérmino, y el bajo peso al nacer, cuando se tienen en cuenta la manifestación clínicas de las enfermedades periodontales en las embarazadas, los hallazgos microbiológicos y las hipótesis propuestas sobre la etiopatogénesis de las complicaciones del embarazo, sugeridas a partir de los hallazgos de estudios realizados en animales y en humanos.
The aim of this bibliographic revision is to show the existing relationship between periodontal disease and some adverse pregnancy outcomes such as preeclampsia, pre-labor rupture of membranes, fetal growth restriction, preterm birth and low birth weight; by taking in account some aspects of the periodontal disease like clinical manifestations during pregnancy, microbiological findings, and the different results found in animal and human casecontrol studies.