RESUMO
Central obesity is characterized by visceral adipose tissue (VAT) expansion, considered one of the main risk factors for metabolic complications. In recent years, new drugs have been studied for obesity treatment. Liraglutide (LGT), a GLP-1 agonist, decreases body weight, however, several mechanisms of action on VAT are still unknown. Aim: to study the effect of LGT on factors associated with VAT remodeling and mitochondrial dynamics in mice fed a high-fat diet (HFD). Methods: C57BL/6 mice were divided into Control (C) and HFD. After 15 weeks of feeding, each group was subdivided according to LGT administration for 5 weeks: C, C + LGT, HFD, and HFD + LGT. In epididymal AT (EAT) we evaluated histological and mitochondrial characteristics, vascularity, gelatinase activity (MMPs), and galectin-3 expression. Results: HFD presented larger adipocytes (p < 0.05), and lower vascular density and MMP-9 activity (p < 0.01) than C, while a major number of smaller adipocytes (p < 0.05) and an increase in vascularity (p < 0.001) and MMP-9 activity (p < 0.01) was observed in HFD + LGT. Collagen content was higher (p < 0.05) in EAT from HFD and decreased in HFD + LGT. In C, C + LGT, and HFD + LGT, mitochondria were predominantly tubular-shaped while in HFD mitochondria were mostly spherical (p < 0.001). Conclusion: LGT positively influences VAT behavior by modulating gelatinase activity, enhancing vascularization, and improving adipocyte histological characteristics. Additionally, LGT improves mitochondrial dynamics, a process that would favor VAT functionality.
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Two well-known protein complexes in mammalian cells, mTOR type 1 and type 2 (mTORC1/2) are involved in several cellular processes such as protein synthesis, cell proliferation, and commonly dysregulated in cancer. An acyl-CoA synthetase type 4 (ACSL4) is one of the most recently mTORC1/2 regulators described, in breast cancer cells. The expression of ACSL4 is hormone-regulated in adrenocortical cells and required for steroid biosynthesis. mTORC1/2 have been reported to be crucial in the proliferation of human adrenocortical tumor cells H295R and interestingly reported at several subcellular locations, which has brought cell biology to the vanguard of the mTOR signaling field. In the present work, we study the regulation of mTORC1/2 activation by angiotensin II (Ang II)-the trophic hormone for adrenocortical cells-the subcellular localization of mTORC1/2 signaling proteins and the role of ACSL4 in the regulation of this pathway, in H295R cells. Ang II promotes activation by phosphorylation of mTORC1/2 pathway proteins in a time-dependent manner. Mitochondrial pools of ribosomal protein S6, protein kinase B (Akt) in threonine 308, and serine 473 and Rictor are phosphorylated and activated. Glycogen synthase kinase type 3 (GSK3) is phosphorylated and inactivated in mitochondria, favoring mTORC1 activation. Epidermal growth factor, a classic mTORC1/2 activator, promoted unique activation kinetics of mTORC1/2 pathway, except for Akt phosphorylation. Here, we demonstrate that ACSL4 is necessary for mTORC1/2 effectors phosphorylation and H295R proliferation, triggered by Ang II. Ang II promotes activation of mitochondrial mTORC1/2 signaling proteins, through ACSL4, with a direct effect on adrenocortical cellular proliferation.
Assuntos
Angiotensina II , Proteínas Proto-Oncogênicas c-akt , Animais , Humanos , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Coenzima A/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Ligases/metabolismo , Mamíferos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Mitocôndrias/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismoRESUMO
We present a case of subcutaneous insulin resistance syndrome, a rare entity, consisting of subcutaneous and intramuscular insulin resistance, with normal or almost normal sensitivity to insulin when administered intravenously. Its cause is unknown and its treatment is challenging. Our patient required a pancreas transplant.
Presentamos un caso de síndrome de resistencia subcutánea a la insulina, entidad infrecuente, que consiste en resistencia a la insulina por vía subcutánea e intramuscular, con sensibilidad normal o casi normal a la insulina cuando se aplica por vía intravenosa. Se desconoce su causa y su tratamiento es un desafío. Nuestra paciente requirió trasplante de páncreas.
Assuntos
Diabetes Mellitus Tipo 1 , Resistência à Insulina , Síndrome Metabólica , Transplante de Pâncreas , Humanos , InsulinaRESUMO
Abstract We present a case of subcutaneous insulin resistance syndrome, a rare entity, consisting of subcutaneous and intramuscular insulin resistance, with normal or almost normal sensitivity to insulin when administered intravenously. Its cause is unknown and its treatment is challenging. Our patient required a pancreas transplant.
Resumen Presentamos un caso de síndrome de resistencia subcutánea a la insulina, entidad in frecuente, que consiste en resistencia a la insulina por vía subcutánea e intramuscular, con sensibilidad normal o casi normal a la insulina cuando se aplica por vía intravenosa. Se desconoce su causa y su tratamiento es un desafío. Nuestra paciente requirió trasplante de páncreas.
Assuntos
Humanos , Resistência à Insulina , Transplante de Pâncreas , Síndrome Metabólica , Diabetes Mellitus Tipo 1 , InsulinaRESUMO
Cystic fibrous osteitis is a complication of a very evolved hyperparathyroidism. Because the determination of calcium, parathyroid hormone and vitamin D have become routine studies, this bone complication is uncommon in western countries. However, it should be considered in the differential diagnosis of hypercalcemia and lytic bone lesions. The treatment is to suppress the excess parathyroid hormone by parathyroidectomy and osteosynthesis in pathological fracture. We present the case of a female patient with primary hyperparathyroidism and a brown tumor in the right tibia.
La osteítis fibrosa quística es la complicación de un hiperparatiroidismo muy evolucionado. Debido a que la determinación del calcio, hormona paratiroides y vitamina D han pasado a ser estudios rutinarios, esta complicación ósea es infrecuente en los países occidentales. Sin embargo, debe ser considerada en el diagnóstico diferencial de hipercalcemia y lesiones óseas líticas. El tratamiento de esta entidad va dirigido a suprimir el exceso de hormona paratiroides mediante la paratiroidectomia y osteosíntesis en los casos de fracturas patológicas. Se presenta el caso de una paciente con hiperparatiroidismo primario y un tumor pardo en la tibia derecha.
Assuntos
Hiperparatireoidismo Primário , Humanos , Estudos Retrospectivos , TíbiaRESUMO
Resumen Se analiza, en un estudio descriptivo retrospectivo, las características clínicas y epidemiológicas, la evolución de la enfermedad y su asociación con los marcadores del laboratorio de mal pronóstico, en los primeros 100 pacientes internados en clínica médica con COVID-19 en el Hospital de Clínicas José de San Martín de la Universidad de Buenos Aires. El 31% de los pacientes provenían de geriátricos, las manifestaciones clínicas más comunes fueron fiebre, tos y odinofagia. En relación a las comorbilidades, la obesidad fue la más frecuente y la hipertensión arterial la más prevalente en los pacientes con neumonía. La edad y la presencia de neumonía fueron los predictores más importantes de mortalidad. Los pacientes mayores de 70 años presentaron reactantes de fase aguda más elevados mostrando una respuesta inflamatoria exagerada. La mortalidad fue elevada (13%), en comparación con la mayoría de las comunicaciones (5%), probablemente como consecuencia de la edad avanzada de nuestra población y las condiciones clínicas desfavorables que presentaron a su ingreso.
Abstract This retrospective descriptive study analyzes the clinical and epidemiological characteristics, the disease evolution and its association with laboratory markers of poor prognosis of the first 100 patients with COVID-19 admitted to internal medicine wards at the Hospital de Clínicas José de San Martín, University of Buenos Aires. Thirty-one patients were nursing home residents, the most common clinical manifestations were fever, cough and odynophagia. Regarding comorbidities, obesity was the most frequent one and hypertension was the most prevalent in patients with pneumonia. The most important predictors of mortality were age and pneumonia. Patients older than 70 years had higher acute phase reactants showing an exaggerated inflammatory response. Mortality was high (13%), compared to most reports (5%), probably because of the advanced age of our population and the unfavorable clinical conditions they presented at admission.
Assuntos
Humanos , COVID-19 , Medicina Interna , Argentina , Universidades , Estudos Retrospectivos , SARS-CoV-2 , HospitaisRESUMO
This retrospective descriptive study analyzes the clinical and epidemiological characteristics, the disease evolution and its association with laboratory markers of poor prognosis of the first 100 patients with COVID-19 admitted to internal medicine wards at the Hospital de Clínicas José de San Martín, University of Buenos Aires. Thirty-one patients were nursing home residents, the most common clinical manifestations were fever, cough and odynophagia. Regarding comorbidities, obesity was the most frequent one and hypertension was the most prevalent in patients with pneumonia. The most important predictors of mortality were age and pneumonia. Patients older than 70 years had higher acute phase reactants showing an exaggerated inflammatory response. Mortality was high (13%), compared to most reports (5%), probably because of the advanced age of our population and the unfavorable clinical conditions they presented at admission.
Se analiza, en un estudio descriptivo retrospectivo, las características clínicas y epidemiológicas, la evolución de la enfermedad y su asociación con los marcadores del laboratorio de mal pronóstico, en los primeros 100 pacientes internados en clínica médica con COVID-19 en el Hospital de Clínicas José de San Martín de la Universidad de Buenos Aires. El 31% de los pacientes provenían de geriátricos, las manifestaciones clínicas más comunes fueron fiebre, tos y odinofagia. En relación a las comorbilidades, la obesidad fue la más frecuente y la hipertensión arterial la más prevalente en los pacientes con neumonía. La edad y la presencia de neumonía fueron los predictores más importantes de mortalidad. Los pacientes mayores de 70 años presentaron reactantes de fase aguda más elevados mostrando una respuesta inflamatoria exagerada. La mortalidad fue elevada (13%), en comparación con la mayoría de las comunicaciones (5%), probablemente como consecuencia de la edad avanzada de nuestra población y las condiciones clínicas desfavorables que presentaron a su ingreso.
Assuntos
COVID-19 , Medicina Interna , Argentina , Hospitais , Humanos , Estudos Retrospectivos , SARS-CoV-2 , UniversidadesRESUMO
Emphysematous cystitis is a complicated form of urinary tract infection, characterized by the presence of air inside the wall and in the light of the bladder, affecting more diabetics, elderly and immunosuppressed. The microorganisms that most frequently cause this entity are Escherichia coli and Klebsiella pneumoniae. Its treatment is based on broad-spectrum antibiotics, bladder catheterization and partial or total cystectomy in severe cases.
La cistitis enfisematosa es una forma complicada de infección urinaria, que se caracteriza por la presencia de aire dentro de la pared y en la luz de la vejiga, que afecta más a diabéticos, ancianos e inmunosuprimidos. Los microorganismo que con mayor frecuencia causan esta entidad son Escherichia coli y Klebsiella pneumoniae. Su tratamiento se basa en antibióticos de amplio espectro, sondaje vesical y cistectomía parcial o total en los casos graves.
Assuntos
Cistite/diagnóstico por imagem , Enfisema/diagnóstico por imagem , Idoso de 80 Anos ou mais , Humanos , Masculino , Tomografia Computadorizada por Raios XRESUMO
In steroid-producing cells, cholesterol transport from the outer to the inner mitochondrial membrane is the first and rate-limiting step for the synthesis of all steroid hormones. Cholesterol can be transported into mitochondria by specific mitochondrial protein carriers like the steroidogenic acute regulatory protein (StAR). StAR is phosphorylated by mitochondrial ERK in a cAMP-dependent transduction pathway to achieve maximal steroid production. Mitochondria are highly dynamic organelles that undergo replication, mitophagy and morphology changes, all processes allowed by mitochondrial fusion and fission, known as mitochondrial dynamics. Mitofusin (Mfn) 1 and 2 are GTPases involved in the regulation of fusion, while dynamin-related protein 1 (Drp1) is the major regulator of mitochondrial fission. Despite the role of mitochondrial dynamics in neurological and endocrine disorders, little is known about fusion/fission in steroidogenic tissues. In this context, the present work aimed to study the role of angiotensin II (Ang II) in protein subcellular compartmentalization, mitochondrial dynamics and the involvement of this process in the regulation of aldosterone synthesis. We demonstrate here that Ang II stimulation promoted the recruitment and activation of PKCε, ERK and its upstream kinase MEK to the mitochondria, all of them essential for steroid synthesis. Moreover, Ang II prompted a shift from punctate to tubular/elongated (fusion) mitochondrial shape, in line with the observation of hormone-dependent upregulation of Mfn2 levels. Concomitantly, mitochondrial Drp1 was diminished, driving mitochondria toward fusion. Moreover, Mfn2 expression is required for StAR, ERK and MEK mitochondrial localization and ultimately for aldosterone synthesis. Collectively, this study provides fresh insights into the importance of hormonal regulation in mitochondrial dynamics as a novel mechanism involved in aldosterone production.
Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Carcinoma Adrenocortical/metabolismo , Angiotensina II/farmacologia , Colesterol/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos , Proteínas Quinases/metabolismo , Vasoconstritores/farmacologia , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Neoplasias das Glândulas Suprarrenais/patologia , Carcinoma Adrenocortical/tratamento farmacológico , Carcinoma Adrenocortical/patologia , Transporte Biológico , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Humanos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fosforilação , Células Tumorais CultivadasRESUMO
Programmed and damage aging theories have traditionally been conceived as stand-alone schools of thought. However, the p66Shc adaptor protein has demonstrated that aging-regulating genes and reactive oxygen species (ROS) are closely interconnected, since its absence modifies metabolic homeostasis by providing oxidative stress resistance and promoting longevity. p66Shc(-/-) mice are a unique opportunity to further comprehend the bidirectional relationship between redox homeostasis and the imbalance of mitochondrial biogenesis and dynamics during aging. This study shows that brain mitochondria of p66Shc(-/-) aged mice exhibit a reduced alteration of redox balance with a decrease in both ROS generation and its detoxification activity. We also demonstrate a strong link between reactive nitrogen species (RNS) and mitochondrial function, morphology, and biogenesis, where low levels of ONOO- formation present in aged p66Shc(-/-) mouse brain prevent protein nitration, delaying the loss of biological functions characteristic of the aging process. Sirt3 modulates age-associated mitochondrial biology and function via lysine deacetylation of target proteins, and we show that its regulation depends on its nitration status and is benefited by the improved NAD+/NADH ratio in aged p66Shc(-/-) brain mitochondria. Low levels of protein nitration and acetylation could cause the metabolic homeostasis maintenance observed during aging in this group, thus increasing its lifespan.
Assuntos
Envelhecimento/metabolismo , Encéfalo/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Sirtuína 3/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Animais , Homeostase , Camundongos , Camundongos KnockoutRESUMO
BACKGROUND Fitz-Hugh-Curtis (FHC) syndrome is a perihepatitis linked to inflammatory pelvic disease. It can be caused by Neisseria gonorrhoeae or Chlamydia trachomatis infections. FHC syndrome usually presents with pain in the right hypochondrium and fever, associated with symptoms and signs of pelvic infection in women. CASE REPORT We present the case of a 22-year-old woman with systemic lupus erythematous (SLE) who presented with polyarthritis, cutaneous lesions, and abdominal pain. The diagnosis of FHC syndrome was based on the findings of abdominal computerized tomography (CT) and the isolation of Neisseria gonorrhoeae (NG) in blood cultures. The association of arthritis and cutaneous lesions was diagnosed as a syndrome of arthritis-dermatitis, also caused by systemic NG infection. The patient had a favorable outcome with antibiotic treatment. CONCLUSIONS FHC syndrome should be considered in sexually active young patients, mainly women, with pelvic infection and perihepatitis. It may be caused by disseminated gonococcal infection. An important risk factor is the serum complement deficit, which may predispose to severe forms. Low serum complement level is a frequent manifestation of active SLE. CT images showing the typical findings of perihepatitis allow making the correct diagnosis.
Assuntos
Infecções por Chlamydia/microbiologia , Gonorreia/diagnóstico , Hepatite/microbiologia , Lúpus Eritematoso Sistêmico/complicações , Doença Inflamatória Pélvica/microbiologia , Peritonite/microbiologia , Feminino , Humanos , Adulto JovemRESUMO
BACKGROUND Takotsubo cardiomyopathy (TM), also called stress myocardiopathy or transient left ventricular apical ballooning syndrome, is characterized by acute left ventricular dysfunction with reversible wall motion abnormalities. TM resembles acute coronary syndrome (ACS) in the absence of coronary artery disease (CAD). In several reports, TM has been described in association with hyperthyroidism, suggesting the potential role of thyrotoxicosis in the pathophysiology. CASE REPORT We present the case of a 34-year-old man with TM associated with hyperthyroidism caused by Graves' disease. In this case, TM was also preceded by an emotional trigger. The diagnosis of TM was based on clinical manifestations, electrocardiographic and echocardiographic abnormalities, and the absence of coronary artery disease (CAD) in the angiography. A diagnosis of hyperthyroidism was made based on hormonal and antibody measurements. The patient had a favorable outcome, and the cardiac and thyroid disorders resolved. CONCLUSIONS Our case illustrates that thyroid disease, mainly hyperthyroidism, should be considered in patients with TM with or without previous emotional triggers. As in our patient, the outcome in TM is usually favorable, with reversibility of cardiac abnormalities.
Assuntos
Doença de Graves/complicações , Cardiomiopatia de Takotsubo/complicações , Adulto , Doença de Graves/diagnóstico , Humanos , Masculino , Cardiomiopatia de Takotsubo/diagnóstico , Cardiomiopatia de Takotsubo/psicologiaRESUMO
BACKGROUND Intravascular lymphoma (IVL) is a rare lymphoproliferative disorder characterized by the proliferation of large B lymphoma cells within the lumen of small-caliber blood vessels. Clinical features are nonspecific, presenting as a systemic disease with fever and may be life-threatening. Antemortem diagnosis is difficult but may be made with biopsies of affected tissues or with random skin biopsies. CASE REPORT We report the case of a 66-year-old white woman presenting with fever of unknown origin (FUO) who developed neurologic, pulmonary, and hematologic manifestations. The diagnosis of intravascular large B cell lymphoma (IVLBCL) was made by random skin biopsies. She received treatment with steroids, rituximab, cyclophosphamide, vincristine, and doxorubicin (R-CHOP). Her disease evolution was unfavorable and she died after her first cycle of chemotherapy. CONCLUSIONS Our case illustrates that IVL can present as FUO and should be considered in the differential diagnosis of this syndrome, especially in patients with neurologic compromise and persistently elevated serum lactate dehydrogenase. In this case, the diagnosis was made with cutaneous biopsies of visibly unaffected skin. As in our patient, the course of IVL is usually fatal within a few months.
Assuntos
Febre de Causa Desconhecida/etiologia , Linfoma Difuso de Grandes Células B/patologia , Pele/patologia , Neoplasias Vasculares/patologia , Idoso , Biópsia , Evolução Fatal , Feminino , Humanos , L-Lactato Desidrogenase/sangueRESUMO
Sepsis-induced myocardial dysfunction is associated with increased oxidative stress and mitochondrial dysfunction. Current evidence suggests a protective role of thioredoxin-1 (Trx1) in the pathogenesis of cardiovascular diseases. However, it is unknown yet a putative role of Trx1 in sepsis-induced myocardial dysfunction, in which oxidative stress is an underlying cause. Transgenic male mice with Trx1 cardiac-specific overexpression (Trx1-Tg) and its wild-type control (wt) were subjected to cecal ligation and puncture or sham surgery. After 6, 18, and 24h, cardiac contractility, antioxidant enzymes, protein oxidation, and mitochondrial function were evaluated. Trx1 overexpression improved the average life expectancy (Trx1-Tg: 36, wt: 28h; p=0.0204). Sepsis induced a decrease in left ventricular developed pressure in both groups, while the contractile reserve, estimated as the response to ß-adrenergic stimulus, was higher in Trx1-Tg in relation to wt, after 6h of the procedure. Trx1 overexpression attenuated complex I inhibition, protein carbonylation, and loss of membrane potential, and preserved Mn superoxide dismutase activity at 24h. Ultrastructural alterations in mitochondrial cristae were accompanied by reduced optic atrophy 1 (OPA1) fusion protein, and activation of dynamin-related protein 1 (Drp1) (fission protein) in wt mice at 24h, suggesting mitochondrial fusion/fission imbalance. PGC-1α gene expression showed a 2.5-fold increase in Trx1-Tg at 24h, suggesting mitochondrial biogenesis induction. Autophagy, demonstrated by electron microscopy and increased LC3-II/LC3-I ratio, was observed earlier in Trx1-Tg. In conclusion, Trx1 overexpression extends antioxidant protection, attenuates mitochondrial damage, and activates mitochondrial turnover (mitophagy and biogenesis), preserves contractile reserve and prolongs survival during sepsis.
Assuntos
Expressão Gênica , Mitocôndrias/genética , Miocárdio/metabolismo , Sepse , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Animais , Antioxidantes/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Doenças Mitocondriais/genética , Miocárdio/patologia , Reação em Cadeia da Polimerase em Tempo Real , Sepse/fisiopatologiaRESUMO
BACKGROUND & AIMS: Hepatocyte apoptosis, the hallmark of non-alcoholic steatohepatitis (NASH) contributes to liver injury and fibrosis. Although, both the intrinsic and extrinsic apoptotic pathways are involved in the pathogenesis of NASH, the final common step of apoptosis is executed by a family of cysteine-proteases termed caspases. Thus, our aim was to ascertain if administration of Emricasan, a pan-caspase inhibitor, ameliorates liver injury and fibrosis in a murine model of NASH. METHODS: C57/BL6J-mice were fed regular chow or high fat diet (HFD) for 20 weeks. All mice were treated with vehicle or Emricasan. RESULTS: Mice fed a HFD diet demonstrate a five-fold increase in hepatocyte apoptosis by the TUNEL assay and a 1.5-fold and 1.3-fold increase in caspase-3 and-8 activities respectively; this increase in apoptosis was substantially attenuated in mice fed a HFD treated with Emricasan (HFD-Em). Likewise, liver injury and inflammation were reduced in mice fed HFD-Em as compare to HFD by measuring serum aspartate aminotransferase and alanine aminotransferase levels, NAS histological score and IL 1-ß, TNF-α, monocyte chemoattractant protein (MCP-1) and C-X-C chemokine ligand-2 (CXCL2) quantitative reverse-transcription polymerase chain reaction (qPCR). These differences could not be attributed to differences in hepatic steatosis as liver triglycerides content were similar in both HFD groups. Hepatic fibrosis was reduced by Emricasan in HFD animals by decreasing αSMA (a marker for hepatic stellate cell activation), fibrosis score, Sirius red staining, hydroxyproline liver content and profibrogenic cytokines by qPCR. CONCLUSION: In conclusion, these data demonstrate that in a murine model of NASH, liver injury and fibrosis are suppressed by inhibiting hepatocytes apoptosis and suggests that Emricasan may be an attractive antifibrotic therapy in NASH.
Assuntos
Apoptose/efeitos dos fármacos , Inibidores de Caspase/uso terapêutico , Hepatócitos/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Ácidos Pentanoicos/uso terapêutico , Animais , Inibidores de Caspase/farmacologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Fibrose , Hepatite/prevenção & controle , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Ácidos Pentanoicos/farmacologiaRESUMO
El objetivo del presente trabajo fue establecer los intervalos de referencia de las determinaciones: glucosa, urea, colesterol, proteínas totales, albúmina, ácido úrico, creatinina, hematocrito y hemoglobina en el Laboratorio Central del Hospital Zonal de Trelew. La población bajo estudio fueron pacientes mayores de 18 años atendidos por consultorio externo entre diciembre de 2008 y marzo de 2009. El estudio fue completado entre marzo y abril de 2011. Las determinaciones se realizaron con un autoanalizador de química clínica Metrolab 2300 plus y un contador hematológico Sysmex 2100. Se comprobó que los valores de las determinaciones se ajustaran a una distribución normal y se realizó el cálculo de los fractiles 0,025 y 0,975 para la obtención del intervalo de referencia (IR) del 95%. En un caso se utilizó transformación logarítmica de los datos y para dos categorías se aplicó el método no paramétrico. Para los valores de referencia inferior y superior se establecieron los intervalos con un 90% de confianza (IC). Los valores de referencia obtenidos fueron: glucosa de 0,74 a 1,07 g/L, urea de 0,19 a 0,51 g/L, colesterol de 1,21 a 2,43 g/L, proteínas totales de 6,45 a 7,99 g/dL, albúmina de 3,62 a 4,61 g/dL, creatinina de 0,57 a 1,10 mg/dL, ácido úrico para el sexo femenino de 18,69 a 51,93 mg/L y para el sexo masculino de 30,50 a 62,92 mg/L, hematocrito para sexo femenino de 37 a 45% y para el sexo masculino de 40 a 50%, hemoglobina para el sexo femenino de 11,70 a 15,17 g/dL y para el sexo masculino de 13,09 a 17,19 g/dL. Los valores de ácido úrico, hematocrito y hemoglobina se separaron por sexo para dar continuidad a la política del laboratorio y de los fabricantes de CAICYTtivos, que consiste en considerar las diferencias existentes entre ambos sexos. Dentro del rango dado por el fabricante se obtuvieron los resultados para glucosa, albúmina y hemoglobina; sobre el mismo, para urea, colesterol, proteínas y ácido úrico y por debajo del mismo para creatinina.
The aim of the present work was to establish the reference intervals of the following determinations, glucose, urea, cholesterol, total proteins, albumin, uric acid, creatinine, hematocrite and hemoglobin in the Central Laboratory of Trelew Zonal Hospital. The population under study was defined as 18-year-old or older patients that came to the laboratory from the ambulatory consulting room since December 2008 to March 2009, and then between March and April 2011. Blood samples were processed with a Metrolab 2300 plus clinical chemistry autoanalyser and a Sysmex 2100 hematological counter. After checking if the result distribution applied to a normal distribution, fractiles 0.025 and 0.975 were calculated to obtain a 95% Reference Interval (RI). In one case, a logarithmic transformation of the results was needed and for two categories a non-parametric method was used. For the upper and lower reference values, the intervals were calculated at 90% confidence (CI) The reference values obtained were; 0.74-1.07 g/L glucose, 0.19-0.51 g/L urea, 1.21-2.43 g/L cholesterol, 6.45-7.99g/dL total proteins, 3.62-4.61 g/dL albumin and 0.57-1.10 mg/dL creatinine, 18.69 - 51.93 mg/L uric acid in women, and 30.50 - 69.92 mg/L in men; 37 - 45% hematocrite in women and 40 - 50% in men; 11.70 - 15.17 g/dL hemoglobin in women and 13.09 - 17.19 g/dL hemoglobin in men. Uric acid, hematocrite and hemoglobin values were calculated according to sex in order to offer concordance with commercial kit and the laboratory policies which consist in considering the significant differences between both sexes. The results obtained for glucose, albumin and hemoglobin were within the reference interval given by the commercial kits; urea, cholesterol, total protein and uric acid were above it; and creatinine reference interval was lower than the reference interval from the commercial kits.
O objetivo do presente trabalho foi estabelecer os intervalos de referencia das determinagóes: glicose, ureia, colesterol, proteínas totais, albumina, ácido úrico, creatinina, hematocrito e hemoglobina no Laboratorio Central do Hospital Zonal de Trelew. A populagao sob estudo foram pacientes de mais de 18 anos atendidos através de consultorio externo entre dezembro do ano 2008 e margo de 2009. O estudo foi completado entre margo e abril de 2011. As determinagóes foram realizadas com um auto-analisador de química clínica Metrolab 2300 plus e um contador hematológico Sysmex 2100. Comprovouse que os valores das determinagóes se ajustaram a uma distribuigao normal e se realizou o cálculo dos quantis 0,025 e 0,975 para a obtengao do intervalo de referencia (IR) de 95%. Num caso foi utilizada transformagao logarítmica dos dados e para duas categorias se aplicou o método nao paramétrico. Para os valores de referencia inferior e superior foram estabelecidos os intervalos com 90% de confianga (IC). Os valores de referencia obtidos foram: glicose de 0,74 a 1,07 gr/L, ureia de 0,19 a 0,51 gr/L, colesterol de 1,21 a 2,43 g/L, proteínas totais de 6,45 a 7,99 gr/dL, albumina de 3,62 a 4,61 gr/dL, creatinina de 0,57 a 1,10 mg/dL, ácido úrico para o sexo feminino de 18,69 a 51,93 mg/L e para o sexo masculino de 30,50 a 62,92 mg/l, hematocrito para sexo feminino de 37 a 45% e para o sexo masculino de 40 a 50%, hemoglobina para o sexo feminino de 11,70 a 15,17 g/dL e para o sexo masculino de 13,09 a 17,19 g/dL. Os valores de ácido úrico, hematocrito e hemoglobina foram separados por sexo para dar continuidade a política do laboratorio e dos fabricantes de reagentes, que consiste em considerar as diferengas existentes entre ambos os sexos. Dentro do intervalo dado pelo fabricante foram obtidos os resultados para glicose, albumina e hemoglobina; superior ao mesmo para ureia, colesterol, proteínas e ácido úrico e inferior ao mesmo para creatinina.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Controle de Qualidade/análise , Técnicas de Química Analítica/normas , Manejo de Espécimes/normas , Albuminas , Métodos de Análise Laboratorial e de Campo , Argentina , Técnicas de Química Analítica/métodos , Colesterol , Creatinina/normas , Glucose/normas , Hematócrito/normas , Hemoglobinas/normas , Valores de ReferênciaRESUMO
AIMS: Obesity arises on defective neuroendocrine pathways that increase energy intake and reduce mitochondrial metabolism. In the metabolic syndrome, mitochondrial dysfunction accomplishes defects in fatty acid oxidation and reciprocal increase in triglyceride content with insulin resistance and hyperglycemia. Mitochondrial inhibition is attributed to reduced biogenesis, excessive fission, and low adipokine-AMP-activated protein kinase (AMPK) level, but lateness of the respiratory chain contributes to perturbations. Considering that nitric oxide (NO) binds cytochrome oxidase and inhibits respiration, we explored NO as a direct effector of mitochondrial dysfunction in the leptin-deficient ob/ob mice. RESULTS: A remarkable three- to fourfold increase in neuronal nitric oxide synthase (nNOS) expression and activity was detected by western blot, citrulline assay, electronic and confocal microscopy, flow cytometry, and NO electrode sensor in mitochondria from ob/ob mice. High NO reduced oxygen uptake in ob/ob mitochondria by inhibition of complex IV and nitration of complex I. Low metabolic status restricted ß-oxidation in obese mitochondria and displaced acetyl-CoA to fat synthesis; instead, small interference RNA nNOS caused a phenotype change with fat reduction in ob/ob adipocytes. INNOVATION: We evidenced that leptin increases mitochondrial respiration and fat utilization by potentially inhibiting NO release. Accordingly, leptin administration to ob/ob mice prevented nNOS overexpression and mitochondrial dysfunction in vivo and rescued leptin-dependent effects by matrix NO reduction, whereas leptin-Ob-Rb disruption increased the formation of mitochondrial NO in control adipocytes. We demonstrated that in ob/ob, hypoleptinemia is associated with critically low mitochondrial p-AMPK and that, oppositely to p-Akt2, p-AMPK is a negative modulator of nNOS. CONCLUSION: Thereby, defective leptin-AMPK pathway links mitochondrial NO to obesity with complex I syndrome and dysfunctional mitochondria.
Assuntos
Adenilato Quinase/metabolismo , Leptina/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Óxido Nítrico/metabolismo , Obesidade/metabolismo , Animais , Western Blotting , Ácidos Graxos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Microscopia Confocal , Microscopia Eletrônica , Mitocôndrias/ultraestrutura , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genéticaRESUMO
Mitochondria are specialized organelles that control energy metabolism and also activate a multiplicity of pathways that modulate cell proliferation and mitochondrial biogenesis or, conversely, promote cell arrest and programmed cell death by a limited number of oxidative or nitrative reactions. Nitric oxide (NO) regulates oxygen uptake by reversible inhibition of cytochrome oxidase and the production of superoxide anion from the mitochondrial electron transfer chain. In this sense, NO produced by mtNOS will set the oxygen uptake level and contribute to oxidation-reduction reaction (redox)-dependent cell signaling. Modulation of translocation and activation of neuronal nitric oxide synthase (mtNOS activity) under different physiologic or pathologic conditions represents an adaptive response properly modulated to adjust mitochondria to different cell challenges.
Assuntos
Metabolismo Energético , Mitocôndrias/enzimologia , Mitocôndrias/fisiologia , Óxido Nítrico Sintase/metabolismo , Estresse Fisiológico , Óxido Nítrico/metabolismoRESUMO
BACKGROUND: In the metabolic syndrome with hyperinsulinemia, mitochondrial inhibition facilitates muscle fat and glycogen accumulation and accelerates its progression. In the last decade, nitric oxide (NO) emerged as a typical mitochondrial modulator by reversibly inhibiting citochrome oxidase and oxygen utilization. We wondered whether insulin-operated signaling pathways modulate mitochondrial respiration via NO, to alternatively release complete glucose oxidation to CO(2) and H(2)O or to drive glucose storage to glycogen. METHODOLOGY/PRINCIPAL FINDINGS: We illustrate here that NO produced by translocated nNOS (mtNOS) is the insulin-signaling molecule that controls mitochondrial oxygen utilization. We evoke a hyperinsulinemic-normoglycemic non-invasive clamp by subcutaneously injecting adult male rats with long-lasting human insulin glargine that remains stable in plasma by several hours. At a precise concentration, insulin increased phospho-Akt2 that translocates to mitochondria and determines in situ phosphorylation and substantial cooperative mtNOS activation (+4-8 fold, P<.05), high NO, and a lowering of mitochondrial oxygen uptake and resting metabolic rate (-25 to -60%, P<.05). Comparing in vivo insulin metabolic effects on gastrocnemius muscles by direct electroporation of siRNA nNOS or empty vector in the two legs of the same animal, confirmed that in the silenced muscles disrupted mtNOS allows higher oxygen uptake and complete (U-(14)C)-glucose utilization respect to normal mtNOS in the vector-treated ones (respectively 37+/-3 vs 10+/-1 micromolO(2)/h.g tissue and 13+/-1 vs 7.2+/-1 micromol (3)H(2)O/h.g tissue, P<.05), which reciprocally restricted glycogen-synthesis by a half. CONCLUSIONS/SIGNIFICANCE: These evidences show that after energy replenishment, insulin depresses mitochondrial respiration in skeletal muscle via NO which permits substrates to be deposited as macromolecules; at discrete hyperinsulinemia, persistent mtNOS activation could contribute to mitochondrial dysfunction with insulin resistance and obesity and therefore, to the progression of the metabolic syndrome.
Assuntos
Insulina/fisiologia , Síndrome Metabólica/metabolismo , Mitocôndrias Musculares/fisiologia , Óxido Nítrico Sintase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ativação Enzimática , Humanos , Síndrome Metabólica/enzimologia , Mitocôndrias Musculares/enzimologia , Músculo Esquelético/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Transdução de SinaisRESUMO
In the last years, nitric oxide synthases (NOS) have been localized in mitochondria. At this site, NO yield directly regulates the activity of cytochrome oxidase, O(2) uptake and the production of reactive oxygen species. Recent studies showed that translocated neuronal nitric oxide synthase (nNOS) is posttranslationally modified including phosphorylation at Ser 1412 (in mice) and myristoylation in an internal residue. Different studies confirm that modified nNOS alpha is the main modulable isoform in mitochondria. Modulation of mtNOS was observed in different situations, like adaptation to reduced O(2) availability and hypoxia, adaptation to low environmental temperature, and processes linked to life and death by effects on kinases and transcription factors. We present here evidence about the role of mtNOS in the analyzed conditions.