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1.
Intern Med ; 61(6): 871-876, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35296622

RESUMO

A 70-year-old woman with complaints of edema, general malaise, and hypotension was diagnosed with renal amyloidosis, and laser microdissection mass spectrometry revealed her amyloidosis to predominantly comprise the apolipoprotein A-IV type. The M-protein turned from negative to positive during the course, and a bone marrow biopsy showed smoldering myeloma. Treatment with bortezomib and dexamethasone failed to save her from heart failure six months after the onset. Western blotting of urine samples at the time of the renal biopsy showed that amyloid light-chain κ amyloidosis had been present since the onset. Unlike the myeloma, Congo red staining was positive in the plasma cells of the bone marrow.


Assuntos
Amiloidose , Amiloidose de Cadeia Leve de Imunoglobulina , Mieloma Múltiplo , Idoso , Amiloidose/complicações , Amiloidose/diagnóstico , Amiloidose/patologia , Apolipoproteínas A , Feminino , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/complicações , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico , Amiloidose de Cadeia Leve de Imunoglobulina/tratamento farmacológico , Mieloma Múltiplo/diagnóstico
2.
Hypertens Res ; 43(10): 1079-1088, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32382157

RESUMO

Vacuolar H+-adenosine triphosphatase (V-ATPase) stimulates vesicular acidification that may activate cytoplasmic enzymes, hormone secretion and membrane recycling of transporters. We investigated the effect of blockade of V-ATPase by bafilomycin B1 on renal gluconeogenesis, mitochondrial enzymes, and insulin secretion in type 2 diabetic rats. Spontaneous type 2 diabetic Torii rats were treated with intraperitoneal injection of bafilomycin B1 for 1 week, and the kidneys were examined after 24 h of starvation in metabolic cages. The renal expression and activity of V-ATPase were increased in the brush border membrane of the proximal tubules in diabetic rats. The blockade of V-ATPase by bafilomycin B1 reduced renal V-ATPase activity and urinary ammonium in diabetic rats. Treatment with bafilomycin suppressed the enhanced renal gluconeogenesis enzymes and mitochondrial electron transport enzymes in type 2 diabetic rats and reduced the renal cytoplasmic glucose levels. The insulin index and pancreatic insulin granules were decreased in diabetic rats with increased V-ATPase expression in islet cells, and treatment with bafilomycin B1 reversed these changes and increased the insulin secretion index. Hepatosteatosis in type 2 diabetic rats was ameliorated by bafilomycin treatment. As a consequence, treatment with bafilomycin B1 significantly decreased the plasma glucose level after 24 h of starvation in diabetic rats. In conclusion, a V-ATPase inhibitor improved plasma glucose levels in type 2 diabetes by inhibiting renal mitochondrial gluconeogenesis and improving insulin secretion.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Gluconeogênese/efeitos dos fármacos , Secreção de Insulina/efeitos dos fármacos , Macrolídeos/uso terapêutico , Animais , Glicemia/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Resistência à Insulina , Rim/efeitos dos fármacos , Rim/enzimologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Macrolídeos/farmacologia , Masculino , Pâncreas/efeitos dos fármacos , Ratos , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores , ATPases Vacuolares Próton-Translocadoras/metabolismo
3.
Toxicol Lett ; 295: 416-423, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30012503

RESUMO

Plasma citrulline is decreased in cases of severe intestinal injury with apparent villus and cellular atrophy. However, the fluctuation of plasma citrulline in slight intestinal injury remains to be investigated. To clarify this, irinotecan at 30 mg/kg or 60 mg/kg was administered intravenously to rats. Irinotecan reduced plasma citrulline concentrations compared to those in the pair-fed control, being concurrent with slight single cell necrosis and mucosal epithelium regeneration in the small intestine without apparent villus and cellular atrophy. Gene expression of enzymes converting glutamine to citrulline was decreased in the small intestine of the injury model. Moreover, citrulline and arginine levels in the ileum were decreased without alterations to glutamine and glutamate levels, indicating that citrulline synthesis from glutamine was impaired. Metabolome analysis revealed that plasma citrulline and arginine levels were decreased, while there were no marked alterations in other amino acids, metabolites of glycolysis, ketone bodies, or fatty acids. These results suggested that a decreased plasma citrulline level was unlikely to result from amino acid catabolism in response to malnutrition. In conclusion, plasma citrulline concentration reflects slight intestinal injury without apparent villus and cellular atrophy, and thus, it would be a sensitive biomarker for the small intestinal injury.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Camptotecina/análogos & derivados , Citrulina/sangue , Íleo/efeitos dos fármacos , Enteropatias/induzido quimicamente , Jejuno/efeitos dos fármacos , Animais , Arginina/sangue , Biomarcadores/sangue , Camptotecina/toxicidade , Regulação para Baixo , Íleo/metabolismo , Íleo/patologia , Enteropatias/sangue , Enteropatias/patologia , Irinotecano , Jejuno/metabolismo , Jejuno/patologia , Masculino , Metabolômica/métodos , Ratos Sprague-Dawley , Fatores de Tempo
5.
Dysphagia ; 31(6): 730-736, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27384435

RESUMO

The objective of this study was to investigate the outcomes of rehabilitation (with swallowing therapy) after percutaneous endoscopic gastrostomy (PEG) in patients with neurogenic dysphagia. Forty-seven patients (29 males and 18 females) who were transferred to the rehabilitation ward of our hospital after receiving PEG tube placements during a 5-year period were enrolled in this study. Patients' demographic data, comorbidities, nutritional statuses, and laboratory biomarkers before the PEG procedure were collected. Rehabilitation (with swallowing therapy) outcomes such as changes in Functional Independence Measure (FIM) and dysphagia grade (using Fujishima's classification) were evaluated. Significant improvements in FIM scores and dysphagia grades after rehabilitation therapy were observed. Twenty-seven patients (57.4 %) were discharged with some oral intake and 10 patients (21.3%) were discharged PEG-free (defined as the PEG tube not being used or removed). Factors associated with being discharged with some oral intake were increase in FIM score (adjusted OR 1.10, 95 % CI 1.02-1.19) and higher baseline dysphagia grade (adjusted OR 1.88, 95 % CI 1.04-3.39). Factors associated with being discharged PEG-free were longer rehabilitation period (OR 1.03, 95 % CI 1.01-1.04), absence of respiratory disorders (OR 0.12, 95 % CI 0.03-0.35), and increase in FIM score (OR 1.17, 95 % CI 1.08-1.28). Changes in dysphagia grade were significantly correlated with changes in FIM score (r 2 = 0.46, p < 0.0001), indicating that improvement of FIM scores through general rehabilitation therapy may play an important role in the treatment of dysphagia.


Assuntos
Transtornos de Deglutição/reabilitação , Endoscopia do Sistema Digestório , Gastrostomia/reabilitação , Recuperação de Função Fisiológica , Adulto , Idoso , Idoso de 80 Anos ou mais , Deglutição , Transtornos de Deglutição/fisiopatologia , Transtornos de Deglutição/cirurgia , Nutrição Enteral/métodos , Feminino , Gastrostomia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
6.
J Clin Neurosci ; 22(9): 1403-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26142049

RESUMO

Motor-evoked potential (MEP) monitoring was performed during 196 consecutive spinal (79 cervical and 117 lumbar) surgeries for the decompression of compressive spinal and spinal nerve diseases. MEP monitoring in spinal surgery has been considered sensitive to predict postoperative neurological recovery. In this series, transcranial stimulation consisted of trains of five pulses at a constant voltage (200-600 V). For the normalization of MEP, we recorded compound muscle action potentials (CMAP) after peripheral nerve stimulation, usually on the median nerve at the wrist 2 seconds before or after each transcranial stimulation of the motor area, for all operations. The sensitivity and specificity of MEP monitoring was 100% and 97.4%, respectively, or 96.9% with or without CMAP compensation (if the threshold of postoperative motor palsy was defined as 20% relative amplitude rate [RAR]). The mean RAR after CMAP normalization, of the most affected muscle in the patient group with excellent postoperative results (recovery rate of a Japan Orthopedic Association score of more than 50%) was significantly higher than that in the other groups (p=0.0224). All patients with an amplitude increase rate (AIR) with CMAP normalization of more than 20% achieved neurological recovery postoperatively. Our results suggest that if the RAR is more than 20%, postoperative motor palsy can be avoided in spinal surgery. If the AIR with normalization by CMAP after peripheral nerve stimulation is more than 20%, neurological recovery can be expected in spinal surgery.


Assuntos
Potenciais de Ação/fisiologia , Descompressão Cirúrgica/métodos , Potencial Evocado Motor/fisiologia , Monitorização Neurofisiológica Intraoperatória/métodos , Síndromes de Compressão Nervosa/cirurgia , Avaliação de Resultados em Cuidados de Saúde/métodos , Doenças da Medula Espinal/cirurgia , Humanos , Sensibilidade e Especificidade
7.
J Child Neurol ; 29(9): NP69-73, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24072019

RESUMO

Acute disseminated encephalomyelitis confined to the brainstem is associated with poor prognosis. We describe a case of a 10-year-old boy with acute disseminated encephalomyelitis in the brainstem that developed after influenza A infection. A 10-year-old boy presented with fever and prolonged disturbance of consciousness and was admitted to our hospital. Magnetic resonance imaging (MRI) of the midbrain, with T2-weighted and fluid-attenuated inversion recovery images, suggested acute disseminated encephalomyelitis accompanied by a brainstem lesion. Lumbar puncture showed pleocytosis and increased protein content, including myelin basic protein, interleukin-6, and immunoglobulin G, all suggestive of acute disseminated encephalomyelitis. Treatments such as methylprednisolone pulse therapy, intravenous immunoglobulin, and therapeutic hypothermia were performed. Although the patient presented with anisocoria with increased intracranial pressure monitoring during hypothermia, prompt therapy with d-mannitol and dopamine was effective. Our case results suggest that hypothermia could be included in the choice of therapy for acute disseminated encephalomyelitis with brainstem lesions.


Assuntos
Tronco Encefálico/patologia , Encefalomielite Aguda Disseminada/fisiopatologia , Encefalomielite Aguda Disseminada/terapia , Hipotermia Induzida/métodos , Pressão Intracraniana , Monitorização Neurofisiológica/métodos , Criança , Encefalomielite Aguda Disseminada/patologia , Humanos , Vírus da Influenza A , Influenza Humana/complicações , Imageamento por Ressonância Magnética , Masculino
9.
J Infect Chemother ; 19(5): 978-82, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23354937

RESUMO

Respiratory syncytial virus (RSV) is a cause of neurological complications in infants. We report a rare case of RSV encephalopathy in an infant who presented with poor sucking and hypothermia at 17 days of age after suffering from rhinorrhea and a cough for several days. After hospitalization, the patient presented with stupor and hypotonia lasting for at least 24 h, and was intubated, sedated, and ventilated for treatment of pneumonia. These symptoms led to diagnosis of pediatric systemic inflammatory response syndrome (SIRS) caused by RSV infection. High-dose steroid therapy was combined with artificial ventilation because the initial ventilation therapy was ineffective. Interleukin (IL)-6 levels in spinal fluid were markedly increased upon admission, and serum IL-6 and IL-8 levels showed even greater elevation. The patient was diagnosed with RSV encephalopathy. On day 5, high signal intensity in the bilateral hippocampus was observed on diffusion-weighted magnetic resonance imaging (MRI). On day 14, the patient presented with delayed partial seizure and an electroencephalogram showed occasional unilateral spikes in the parietal area, but the hippocampal abnormality had improved to normal on MRI. (99m)Tc-labeled ethylcysteinate dimer single-photon emission computed tomography (SPECT) on day 18 showed hypoperfusion of the bilateral frontal and parietal regions and the unilateral temporal region. SPECT at 3 months after onset still showed hypoperfusion of the bilateral frontal region and unilateral temporal region, but hypoperfusion of the bilateral parietal region had improved. The patient has no neurological deficit at 6 months. These findings suggest that RSV encephalopathy with cytokine storm induces several symptoms and complications, including SIRS and prolonged brain hypoperfusion on SPECT.


Assuntos
Encefalopatias/patologia , Encefalopatias/virologia , Infecções por Vírus Respiratório Sincicial/patologia , Síndrome de Resposta Inflamatória Sistêmica/patologia , Síndrome de Resposta Inflamatória Sistêmica/virologia , Encéfalo/patologia , Humanos , Recém-Nascido , Masculino , Infecções por Vírus Respiratório Sincicial/virologia , Convulsões/patologia , Convulsões/virologia
11.
Arerugi ; 61(1): 30-40, 2012 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-22398426

RESUMO

BACKGROUND: A 7-year analysis of pediatric asthma in Tochigi was performed with the aim of improvement of future treatment. METHODS: Self-administered questionnaires were completed by pediatric asthma patients and their parents who visited pediatric clinics or hospitals in Tochigi at the same period of year in 2002, 2006, and 2008. Changes in asthma symptoms and in the QOL of the patients and their parents were analyzed. Data on the background and treatment of the patients were obtained from doctors. RESULTS: The questionnaires were answered by 1487, 1058, and 1014 patients or parents in 2002, 2006, and 2008, respectively. The results showed significant increases in the use of ICS and LTRA (p< 0.001, for each.) and significant decreases in the use of theophylline, DSCG, and LABA (p< 0.001, for each.). Frequency of wheezing, cough and sputum were significantly reduced in all age groups (p< 0.01, for each.). There were significant reductions of frequency of wheezing in patients under 2 years old; in wheezing and cough in patients aged 2-5 years old; and in wheezing, cough and sputum in patients aged 6-15 years old (p< 0.05 for each.). The QOL of the patients and their parents was significantly improved in all age groups (p< 0.05 for each.). CONCLUSION: These findings suggest that increased use of anti-inflammatory agents such as LTRA and ICS have contributed to a reduction in asthma symptoms and an improvement in the QOL of the pediatric patients and their parents, but more widespread use of these agents are still needed for residual uncontrolled asthma patients.


Assuntos
Corticosteroides/administração & dosagem , Asma/tratamento farmacológico , Asma/fisiopatologia , Antagonistas de Leucotrienos/administração & dosagem , Qualidade de Vida , Administração por Inalação , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
12.
J Toxicol Sci ; 36(1): 9-22, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21297337

RESUMO

The present study was designed to fully uncover sex and circadian modulatory effects on rat liver. Hepatic transcriptome analyses were performed at 4 hr intervals of a day-night cycle using young adult male and female rats. Sexually dimorphic genes, which were identified by a cross-sex comparison of time series data, included representative sex-predominant genes such as male- or female-predominant cytochrome P450 subfamilies (Cyp2c11, Cyp2c12, Cyp2c13, and Cyp3a2), sulfotransferases, and glutathione S-transferase Yc2. The identified sexually dimorphic genes were over-represented in the metabolism of retinols, xenobiotics, linoleic acids, or androgen and estrogen, or bile acid biosynthesis. Furthermore, transcription factor targets modeling suggested that transcription factors SP1, hepatocyte nuclear factor 4-alpha (HNF4-alpha), and signal transducer and activator of transcription 5b (STAT5b) serve as core nodes in the regulatory networks. On the other hand, Fourier transform analyses extracted universal circadian-regulated genes in both sexes. The circadian-regulated genes included clock or clock-controlled genes such as aryl hydrocarbon receptor nuclear translocator-like (Arntl), period homolog 2 (Per2), and D site albumin promoter binding protein (Dbp). The extracted cyclic genes were over-represented in major tissue activities, e.g. the urea cycle and the metabolism of amino acids, fatty acids, or glucose, indicating that the major liver functions are under circadian control. The transcription factor targets modeling suggested that transcription factors SP1, HNF4-alpha, and c-Myc proto-oncogene protein (c-MYC) serve as major hubs in the circadian-regulatory gene networks. Interestingly, transcription factors SP1 and HNF4-alpha are likely to orchestrate not only sexually dimorphic, but also circadian-regulated genes even though each criterion was rather mutually exclusive. This suggests the cross-talk between those regulations. Sexual dimorphism is likely to interact with circadian rhythmicity via overlapping gene regulatory networks on rat liver.


Assuntos
Ritmo Circadiano/genética , Perfilação da Expressão Gênica/métodos , Fígado/fisiologia , Caracteres Sexuais , Fatores de Transcrição ARNTL , Animais , Ritmo Circadiano/fisiologia , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Ligação a DNA , Feminino , Glutationa Transferase/metabolismo , Fígado/enzimologia , Fígado/metabolismo , Masculino , Proteínas Circadianas Period , Proto-Oncogene Mas , Ratos , Ratos Endogâmicos F344 , Sulfotransferases/metabolismo , Fatores de Transcrição
13.
J Toxicol Sci ; 35(5): 673-85, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20930462

RESUMO

The secretory profile of growth hormone (GH) is sexually dimorphic in rats. In male transgenic (TG) rats expressing human GH (hGH) that we generated, the circulating levels of both hGH and endogenous GH are flattened with no male-type pulsatility. To elucidate the regulatory role of episodic GH profile on the liver, the hepatic transcriptome of male TG rats at the middle of the light and dark phases was characterized by genome-wide analyses as compared with that of male wild-type (WT) rats. Transcripts commonly up- or down-regulated regardless of the lighting conditions in TG rats were mainly enriched in the metabolism of xenobiotics. In TG rats, the gene expression profile was functionally feminized, verifying that the sexually dimorphic profile of GH rather than genetic sexuality is a stronger sex-determining factor on the hepatic transcriptome. The common transcripts which fluctuated during the day in both TG and WT rats were enriched in circadian rhythm signaling, and physiological rhythmicity was considered to be finely interconnected with liver metabolism via sexually dimorphic GH secretion. In contrast, some genes were differentially regulated in TG rats at only one of two time points measured, and others were fluctuated daily in only one genotype. In particular, some genes involved in the GH signaling pathway were included, suggesting the signal transduction is circadian-modulated depending upon the GH profile. Our transcriptome analyses clarified the regulatory role of episodic GH profile on the liver and strengthen the functional link between sexually dimorphic GH secretion, liver metabolism, and its circadian regulation.


Assuntos
Ritmo Circadiano , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Hormônio do Crescimento Humano/biossíntese , Fígado/metabolismo , Animais , Ritmo Circadiano/genética , Glutationa Transferase/genética , Humanos , Immunoblotting , Fígado/enzimologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Transgênicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
J Biol Chem ; 281(6): 3165-71, 2006 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-16332680

RESUMO

Hepatic P450 monooxygenase activities, assessed by measurement of 7-alkoxycoumarin O-dealkylase (ACD) activities, show obvious daily fluctuations in male rats with high values during the dark period and low values during the light period. We have already confirmed that the ACD activities are controlled by the suprachiasmatic nucleus (SCN), which is well known as the oscillator of circadian rhythm. Recently, it is reported that circadian oscillators exist not only in the SCN but also in peripheral organs. To date, it is unclear which circadian oscillators predominantly drive the daily fluctuations of hepatic ACD activities. To address this question, we examined the effects of restricted feeding, which uncouples the circadian oscillators in the liver from the central pacemaker in the SCN, on the daily fluctuations in hepatic ACD activities in male rats. Here we show that restricted feeding inverts the oscillation phase of the daily fluctuations in hepatic ACD activities. Regarding the hepatic P450 content, there were no fluctuations between the light and dark periods under ad libitum and restricted feeding conditions. Therefore, it is considered that the daily fluctuations in hepatic ACD activities are predominantly driven by the circadian factors in peripheral organs rather than by the oscillator in the SCN directly.


Assuntos
Sistema Enzimático do Citocromo P-450/biossíntese , Privação de Alimentos , Fígado/enzimologia , O-Dealquilase 7-Alcoxicumarina/biossíntese , Animais , Peso Corporal , Ritmo Circadiano , Perfilação da Expressão Gênica , Luz , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Oscilometria , RNA/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos F344 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Núcleo Supraquiasmático/enzimologia , Fatores de Tempo , Transcrição Gênica
15.
Brain Dev ; 27(5): 370-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16023555

RESUMO

We retrospectively reviewed the medical records of neonates with chromosomal abnormalities and epilepsy who had been admitted to the neonatal intensive care unit (NICU) and followed up at the outpatient clinic of Dokkyo University School of Medicine. Chromosomal anomalies were diagnosed in 128 of 5789 patients admitted from 1978 through 2001. Seventy-one neonates had trisomy 21, 29 had trisomy 18, 8 had trisomy 13, and 20 had other chromosomal anomalies. Seizures occurred in five patients with trisomy 21 and in one patient each with trisomy 18, 6q-, 13q-, 21q-, and mosaicism trisomy 13. Two patients with 4p- [Wolf-Hirschhorn syndrome] were admitted to the NICU, but were not followed up at our outpatient clinic. The boy with 6q- (46,XY,-6, +der(6)t(6;11)(q25.1;q23.3)mat) had agenesis of the corpus callosum and multiple congenital anomalies as well as intractable epilepsy. The girl with 13q- (46, XX, t(2,4)(q24.2;p14), del (13)(q21.2q31.2)) had infantile spasms at 12 months, which were well controlled with nitrazepam and vitamin B6. The girl with mosaic trisomy 8q; (46, XX, der(8) (qter-->q11.2::p23.3-->qter)/46, XX), was not born at our hospital, but showed unique clinical features. She had intractable epilepsy characterized by episodes of vomiting and staring with astatic seizures. Computed tomography of the brain revealed bilateral calcification in the globus pallidus, associated with bursts of high-amplitude slow waves on electroencephalography. One of the two patients with del(15)(q12)[Angelman syndrome] had giant-amplitude visual evoked potential, suggesting hyperexcitability of the visual cortex.


Assuntos
Encéfalo/patologia , Encéfalo/fisiopatologia , Transtornos Cromossômicos/genética , Transtornos Cromossômicos/patologia , Epilepsia/genética , Pré-Escolar , Transtornos Cromossômicos/fisiopatologia , Eletroencefalografia , Epilepsia/patologia , Epilepsia/fisiopatologia , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos
16.
Arch Toxicol ; 78(8): 435-42, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15107969

RESUMO

Phenobarbital (PB) increases serum total cholesterol levels in rodents and humans. To investigate the underlying molecular mechanisms, we performed a microarray analysis on liver of rats treated repeatedly with 100 mg/kg PB, and examined the serum blood chemistry. The serum concentration of non-esterified fatty acids was decreased from day 1 to day 14 except for day 7, and that of cholesterol was increased from day 4 to day 14. The serum concentration of total ketone bodies was increased on day 7, and that of triglycerides was decreased on day 14. Transcript content of glycolytic genes was decreased by PB treatments, while that of lipoprotein lipase was continuously increased, suggesting a notion that repetitive PB treatments impaired glycolysis and stimulated lipolysis in the liver. The hypothesis was examined by using a previously reported flux-balance model. The increase in mRNA content of malic enzyme after the PB treatment agreed well with the flux-balance model result, suggesting the validity of our hypothesis. The findings also suggested that there was an abundance of acetyl-CoA and shortage of glycolytic products after the repeated PB treatments. Although ketogenesis would normally occur under such cellular conditions, it was only weakly observed after the repeated PB treatments, presumably owing to a decrease in HMG-CoA synthase mRNA content. On the other hand, the mRNA content of several cholesterogenic genes was slightly induced by PB treatments. Thus, serum chemistry and microarray results suggested that repeated PB treatments induced cholesterogenesis in rat livers, which may have contributed to the elevation of the serum total cholesterol concentration.


Assuntos
Colesterol/sangue , Colesterol/genética , Hipnóticos e Sedativos/farmacologia , Fígado/metabolismo , Fenobarbital/farmacologia , Animais , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Ácidos Graxos não Esterificados/sangue , Corpos Cetônicos/sangue , Fígado/efeitos dos fármacos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Ratos , Ratos Endogâmicos F344 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triglicerídeos/sangue
17.
Biochim Biophys Acta ; 1607(1): 35-44, 2003 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-14556911

RESUMO

In order to get insight into the origin of apparent negative cooperativity observed for F(1)-ATPase, we compared ATPase activity and ATPMg binding of mutant subcomplexes of thermophilic F(1)-ATPase, alpha((W463F)3)beta((Y341W)3)gamma and alpha((K175A/T176A/W463F)3)beta((Y341W)3)gamma. For alpha((W463F)3)beta((Y341W)3)gamma, apparent K(m)'s of ATPase kinetics (4.0 and 233 microM) did not agree with apparent K(m)'s deduced from fluorescence quenching of the introduced tryptophan residue (on the order of nM, 0.016 and 13 microM). On the other hand, in case of alpha((K175A/T176A/W463F)3)beta((Y341W)3)gamma, which lacks noncatalytic nucleotide binding sites, the apparent K(m) of ATPase activity (10 microM) roughly agreed with the highest K(m) of fluorescence measurements (27 microM). The results indicate that in case of alpha((W463F)3)beta((Y341W)3)gamma, the activating effect of ATP binding to noncatalytic sites dominates overall ATPase kinetics and the highest apparent K(m) of ATPase activity does not represent the ATP binding to a catalytic site. In case of alpha((K175A/T176A/W463F)3)beta((Y341W)3)gamma, the K(m) of ATPase activity reflects the ATP binding to a catalytic site due to the lack of noncatalytic sites. The Eadie-Hofstee plot of ATPase reaction by alpha((K175A/T176A/W463F)3)beta((Y341W)3)gamma was rather linear compared with that of alpha((W463F)3)beta((Y341W)3)gamma, if not perfectly straight, indicating that the apparent negative cooperativity observed for wild-type F(1)-ATPase is due to the ATP binding to catalytic sites and noncatalytic sites. Thus, the frequently observed K(m)'s of 100-300 microM and 1-30 microM range for wild-type F(1)-ATPase correspond to ATP binding to a noncatalytic site and catalytic site, respectively.


Assuntos
Trifosfato de Adenosina/química , Magnésio/química , Modelos Químicos , ATPases Translocadoras de Prótons/química , Sítios de Ligação , Catálise , Ativação Enzimática , Complexos Multienzimáticos/química , Ligação Proteica , Subunidades Proteicas
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