RESUMO
Primary triglyceride deposit cardiomyovasculopathy (P-TGCV), caused by a rare genetic mutation in PNPLA2 encoding adipose triglyceride lipase (ATGL), exhibits severe cardiomyocyte steatosis and heart failure. Here, we report the case of a 51-year-old man with P-TGCV homozygous for a novel PNPLA2 mutation (c.446C > G, P149R) in the catalytic domain of ATGL. Analyses of endomyocardial biopsy specimens and in vitro expression experiments showed mutant protein expression with conserved lipid binding, but reduced lipolytic activity, indicating mutation pathogenicity.
RESUMO
Triglyceride deposit cardiomyovasculopathy (TGCV) is a phenotype primarily reported in patients carrying genetic mutations in PNPLA2 encoding adipose triglyceride lipase (ATGL) which releases long chain fatty acid (LCFA) as a major energy source by the intracellular TG hydrolysis. These patients suffered from intractable heart failure requiring cardiac transplantation. Moreover, we identified TGCV patients without PNPLA2 mutations based on pathological and clinical studies. We provided the diagnostic criteria, in which TGCV with and without PNPLA2 mutations were designated as primary TGCV (P-TGCV) and idiopathic TGCV (I-TGCV), respectively. We hereby report clinical profiles of TGCV patients. Between 2014 and 2018, 7 P-TGCV and 18 I-TGCV Japanese patients have been registered in the International Registry. Patients with I-TGCV, of which etiologies and causes are not known yet, suffered from adult-onset severe heart disease, including heart failure and coronary artery disease, associated with a marked reduction in ATGL activity and myocardial washout rate of LCFA tracer, as similar to those with P-TGCV. The present first registry-based study showed that TGCV is an intractable, at least at the moment, and heterogeneous cardiovascular disorder.
Assuntos
Doenças Cardiovasculares/metabolismo , Doenças Raras/metabolismo , Triglicerídeos/metabolismo , Adulto , Idoso , Aterosclerose/genética , Aterosclerose/metabolismo , Doenças Cardiovasculares/patologia , Feminino , Humanos , Lipase/genética , Lipase/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Doenças Raras/patologiaRESUMO
BACKGROUND: Citrin (mitochondrial aspartate-glutamate transporter) deficiency causes the failures in both carbohydrate-energy metabolism and the urea cycle, and the alterations in the serum levels of several amino acids in the stages of newborn (NICCD) and adult (CTLN2). However, the clinical manifestations are resolved between the NICCD and CTLN2, but the reasons are still unclear. This study evaluated the serum amino acid profile in citrin-deficient children during the healthy stage. METHODS: Using HPLC-MS/MS analysis, serum amino acids were evaluated among 20 citrin-deficient children aged 5-13 years exhibiting normal liver function and 35 age-matched healthy controls. RESULTS: The alterations in serum amino acids characterized in the NICCD and CTLN2 stages were not observed in the citrin-deficient children. Amino acids involved in the urea cycle, including arginine, ornithine, citrulline, and aspartate, were comparable in the citrin-deficient children to the respective control levels, but serum urea was twofold higher, suggestive of a functional urea cycle. The blood sugar level was normal, but glucogenic amino acids and glutamine were significantly decreased in the citrin-deficient children compared to those in the controls. In addition, significant increases of ketogenic amino acids, branched-chain amino acids (BCAAs), a valine intermediate 3-hydroxyisobutyrate, and ß-alanine were also found in the citrin-deficient children. CONCLUSION: The profile of serum amino acids in the citrin-deficient children during the healthy stage showed different characteristics from the NICCD and CTLN2 stages, suggesting that the failures in both urea cycle function and energy metabolism might be compensated by amino acid metabolism. SYNOPSIS: In the citrin-deficient children during the healthy stage, the characteristics of serum amino acids, including decrease of glucogenic amino acids, and increase of ketogenic amino acids, BCAAs, valine intermediate, and ß-alanine, were found by comparison to the age-matched healthy control children, and it suggested that the characteristic alteration of serum amino acids may be resulted from compensation for energy metabolism and ammonia detoxification.
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Triglyceride deposit cardiomyovasculopathy (TGCV) is an intractable cardiovascular disease for which a specific treatment is urgently required. In TGCV, adipose triglyceride lipase (ATGL) deficiency results in the abnormal intracellular metabolism of long-chain fatty acid (LCFA) which leads to TG deposition. Medium-chain triglycerides have been used as an important functional food for various human diseases. To address the potential activities of tricaprin, a medium-chain triglyceride, on cardiac dysfunctions of TGCV, we examined the effects of tricaprin diet on Atgl knock out (KO) mice, an animal model for TGCV. Cardiac imaging tests showed that the tricaprin diet reduced TG accumulation, resulting from improvement of LCFA metabolism, and improved left ventricular function in Atgl KO mice compared to that in mice fed the control diet. In conclusion, tricaprin improved myocardial abnormality in the TGCV model, thus, it may be useful for the treatment of patients with TGCV.
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Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Lipase/deficiência , Miocárdio/metabolismo , Triglicerídeos/metabolismo , Animais , Doenças Cardiovasculares/diagnóstico por imagem , Modelos Animais de Doenças , Ácidos Graxos/metabolismo , Coração/diagnóstico por imagem , Humanos , Camundongos Knockout , Triglicerídeos/administração & dosagemRESUMO
BACKGROUND: Causative mutations cannot be identified in the majority of Asian patients with suspected maturity-onset diabetes of the young (MODY). OBJECTIVES: To elucidate the genetic basis of Japanese patients with MODY-like diabetes and gain insight into the etiology of patients without mutations in the major MODY genes. SUBJECTS: A total of 263 Japanese patients with early-onset, non-obese, MODY-like diabetes mellitus referred to Osaka City General Hospital for diagnosis. METHODS: Mutational analysis of the four major MODY genes (GCK, HNF1A, HNF4A, HNF1B) by Sanger sequencing. Mutation-positive and mutation-negative patients were further analyzed for clinical features. RESULTS: Mutations were identified in 103 (39.2%) patients; 57 mutations in GCK; 29, HNF1A; 7, HNF4A; and 10, HNF1B. Contrary to conventional diagnostic criteria, 18.4% of mutation-positive patients did not have affected parents and 8.2% were in the overweight range (body mass index [BMI] >85th percentile). HOMA-IR at diagnosis was elevated (>2) in 15 of 66 (22.7%) mutation-positive patients. Compared with mutation-positive patients, mutation-negative patients were significantly older (P = 0.003), and had higher BMI percentile at diagnosis (P = 0.0006). Interestingly, maternal inheritance of diabetes was significantly more common in mutation-negative patients (P = 0.0332) and these patients had significantly higher BMI percentile as compared with mutation-negative patients with paternal inheritance (P = 0.0106). CONCLUSIONS: Contrary to the conventional diagnostic criteria, de novo diabetes, overweight, and insulin-resistance are common in Japanese patients with mutation-positive MODY. A significant fraction of mutation-negative patients had features of early-onset type 2 diabetes common in Japanese, and non-Mendelian inheritance needs to be considered for these patients.
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Diabetes Mellitus Tipo 2/genética , Fatores Nucleares de Hepatócito/genética , Herança Materna , Proteínas Serina-Treonina Quinases/genética , Adolescente , Adulto , Criança , Pré-Escolar , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Quinases do Centro Germinativo , Humanos , Japão/epidemiologia , Masculino , Adulto JovemRESUMO
Context: Citrin-deficient infants present neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD), which resolves at 12 months. Thereafter, they have normal liver function associated with hypercholesterolemia, and a preference for lipid-rich carbohydrate-restricted diets. However, some develop adult-onset type II citrullinemia, which is associated with metabolic abnormalities. Objectives: To identify the causes of hypercholesterolemia in citrin-deficient children post-NICCD. Design and Setting: We determined the concentrations of sterol markers of cholesterol synthesis, absorption, and catabolism by liquid chromatography-electrospray ionization-tandem mass spectrometry and evaluated serum lipoprotein profiles. Subjects: Twenty citrin-deficient children aged 5 to 13 years and 37 age-matched healthy children. Intervention: None. Main Outcome Measures: Relationship between serum lipoproteins and sterol markers of cholesterol metabolism. Results: The citrin-deficient group had a significantly higher high-density lipoprotein cholesterol (HDL-C) concentration than did the control group (78 ± 11 mg/dL vs 62 ± 14 mg/dL, P < 0.001), whereas the two groups had similar low-density lipoprotein cholesterol and triglyceride concentrations. The concentrations of markers of cholesterol synthesis (lathosterol and 7-dehydrocholesterol) and bile acids synthesis (7α-hydroxycholesterol and 27-hydroxycholesterol) were 1.5- to 2.8-fold and 1.5- to 3.9-fold, respectively, higher in the citrin-deficient group than in the control group. The concentration of 24S-hydroxycholesterol, a marker of cholesterol catabolism in the brain, was 2.5-fold higher in the citrin-deficient group. In both groups, the HDL-C concentration was significantly positively correlated with that of 27-hydroxycholesterol, the first product of the alternative bile acid synthesis pathway. Conclusions: HDL-C and sterol marker concentrations are elevated in citrin-deficient children post-NICCD. Moreover, cholesterol synthesis and elimination are markedly enhanced in the liver and brain of citrin-deficient children.
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Encéfalo/metabolismo , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Citrulinemia/metabolismo , Hipercolesterolemia/etiologia , Fígado/metabolismo , Adolescente , Ácidos e Sais Biliares/biossíntese , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Colesterol/sangue , Citrulinemia/complicações , Desidrocolesteróis/sangue , Feminino , Humanos , Hidroxicolesteróis/sangue , Masculino , Triglicerídeos/sangueRESUMO
OBJECTIVE: CD36 deficiency is characterized by limited cellular long chain fatty acid uptake in the skeletal and cardiac muscles and often causes energy crisis in these muscles. However, suitable treatment for CD36 deficiency remains to be established. The aim of this study was to evaluate the clinical and metabolic effects of medium chain triacylglycerols (MCTs) in two CD36-deficient preschool children who often developed fasting hypoglycemia and exercise-induced myalgia. METHODS: Fasting blood glucose, total ketone bodies, and free fatty acids were examined and compared for usual supper diets and for diets with replacement of one component with 2 g/kg of 9% MCT-containing milk (MCT milk). Changes in serum creatine kinase and alanine aminotransferase levels, resulting from replacement of glucose water intake with 1 g/kg of MCT milk and determined by using bicycle pedaling tasks, were examined and compared. Hypoglycemic and/or myalgia episodes in daily life were also investigated. RESULTS: Biochemically, participants' blood glucose and total ketone bodies levels after overnight fasting substantially increased after dietary suppers containing MCT milk. Increases in serum creatine kinase and alanine aminotransferase levels resulting from the bicycle pedaling task were suppressed by MCT milk. Hypoglycemia leading to unconsciousness and tachycardia before breakfast decreased after introduction of dietary suppers containing MCT milk. Occurrence of myalgia in the lower limbs also decreased after intakes of MCT milk before long and/or strenuous exercising. CONCLUSION: Our results suggest that MCTs can prevent fasting hypoglycemia and exercise-induced myalgia in CD36-deficient young children.
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Transtornos Plaquetários/dietoterapia , Gorduras na Dieta/administração & dosagem , Alimentos Fortificados/análise , Doenças Genéticas Inatas/dietoterapia , Leite/química , Triglicerídeos/administração & dosagem , Alanina Transaminase/sangue , Animais , Glicemia/análise , Transtornos Plaquetários/sangue , Transtornos Plaquetários/complicações , Pré-Escolar , Creatina Quinase/sangue , Exercício Físico/fisiologia , Jejum/sangue , Ácidos Graxos não Esterificados/sangue , Doenças Genéticas Inatas/sangue , Doenças Genéticas Inatas/complicações , Humanos , Hipoglicemia/etiologia , Hipoglicemia/prevenção & controle , Cetonas/sangue , Masculino , Mialgia/etiologia , Mialgia/prevenção & controle , Resultado do TratamentoRESUMO
Triglyceride deposit cardiomyovasculopathy (TGCV) is a rare and newly identified disease among patients requiring cardiac transplantation. TGCV is characterized by cardiomyocyte steatosis and triglyceride (TG)-deposit atherosclerosis, resulting from the abnormal intracellular metabolism of TG. TGCV is classified into primary and idiopathic types. Primary TGCV carries ultra-rare genetic mutations in the adipose triglyceride lipase (ATGL), a rate-liming enzyme that hydrolyzes intracellular TG in adipose and non-adipose tissues. Idiopathic TGCV, first identified among autopsied individuals with diabetes mellitus (DM) with severe heart diseases, shows no ATGL mutations and its causes and underlying mechanisms are still unknown. TGCV is difficult to diagnose in daily clinics, thereby demanding feasible diagnostic procedures. We aimed to develop an assay to measure ATGL activity using peripheral leucocytes. Human his6-ATGL was expressed in COS1 cells, purified to homogeneity, and used to raise a polyclonal antibody neutralizing TG-hydrolyzing activity of ATGL. We developed a selective immunoinactivation assay (SIIA) for the quantitation of ATGL activity in cell lysates of leucocytes by the antibody neutralizing ATGL activities. ATGL activity was measured in 13 idiopathic TGCV patients, with two patients with primary TGCV as the negative control. Healthy (non-DM) and DM controls without heart diseases were also subjected. The developed SIIA assay revealed significant reduction in ATGL activity in leucocytes from patients with idiopathic TGCV who did not carry ATGL mutations as compared with non-DM and DM controls. Thus, ATGL in leucocytes may be an important biomarker for the diagnosis of TGCV and our assay may provide insights into pathophysiology and elucidate the underlying mechanism of TGCV and related disorders.
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Cardiomiopatias/sangue , Cardiomiopatias/enzimologia , Técnicas Imunoenzimáticas/métodos , Leucócitos/enzimologia , Lipase/metabolismo , Idoso , Biomarcadores/metabolismo , Ativação Enzimática , Feminino , Humanos , Leucócitos/imunologia , Lipase/imunologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Objective To investigate the basal amino acid metabolism and impact of growth hormone (GH) therapy in short-stature children born small for gestational age (short SGA children). Methods In this age-matched case-control study, the basal blood levels of amino acids, asymmetric dimethylarginine (ADMA), and nitrite/nitrate (NOx) were compared between 24 short SGA children and 25 age-matched normal children. Changes in these parameters were assessed for 12 months in 12 short SGA children initiating GH therapy (Group A) and 12 age-matched short SGA children without GH therapy (Group B). Results The arginine levels were significantly lower in the short SGA than in normal children. The ADMA levels were significantly higher and NOx levels were significantly lower in the short SGA than normal children. In Group A, the ADMA level was significantly lower and NOx level was significantly higher at 6 months than at baseline. At 12 months, the ADMA level in Group A began to increase, but the NOx level remained the same. Group B showed no significant changes. Conclusions This study is the first to show that ADMA is promoted and nitric oxide is suppressed in short SGA children and that GH therapy affects the production of ADMA and nitric oxide.
Assuntos
Arginina/análogos & derivados , Nanismo/tratamento farmacológico , Hormônio do Crescimento/uso terapêutico , Nitratos/sangue , Nitritos/sangue , Arginina/sangue , Biomarcadores/sangue , Estatura/efeitos dos fármacos , Estudos de Casos e Controles , Criança , Pré-Escolar , Nanismo/sangue , Nanismo/diagnóstico , Nanismo/fisiopatologia , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional/sangue , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Estudos Longitudinais , MasculinoRESUMO
Progressive familial intrahepatic cholestasis type 1 (PFIC1), a rare inherited recessive disease resulting from a genetic deficiency in ATP8B1, progresses to liver failure. Because of the difficulty of discriminating PFIC1 from other subtypes of PFIC based on its clinical and histological features and genome sequencing, an alternative method for diagnosing PFIC1 is desirable. Herein, we analyzed human peripheral blood monocyte-derived macrophages (HMDM) and found predominant expression of ATP8B1 in interleukin-10 (IL-10)-induced M2c, a subset of alternatively activated macrophages. SiRNA-mediated depletion of ATP8B1 in IL-10-treated HMDM markedly suppressed the expression of M2c-related surface markers and increased the side scatter (SSC) of M2c, likely via impairment of the IL-10/STAT3 signal transduction pathway. These phenotypic features were confirmed in IL-10-treated HMDM from four PFIC1 patients with disease-causing mutations in both alleles, but not in those from four patients with other subtypes of PFIC. This method identified three PFIC1 patients in a group of PFIC patients undiagnosed by genome sequencing, an identical diagnostic outcome to that achieved by analysis of liver specimens and in vitro mutagenesis studies. In conclusion, ATP8B1 deficiency caused incomplete polarization of HMDM into M2c. Phenotypic analysis of M2c helps to identify PFIC1 patients with no apparent disease-causing mutations in ATP8B1.
Assuntos
Adenosina Trifosfatases/deficiência , Colestase/sangue , Colestase/metabolismo , Macrófagos/metabolismo , Monócitos/patologia , Adenosina Trifosfatases/metabolismo , Adolescente , Biomarcadores/metabolismo , Criança , Pré-Escolar , Colestase/diagnóstico , Colestase/patologia , Feminino , Humanos , Interleucina-10/metabolismo , Fígado/metabolismo , Fígado/patologia , Macrófagos/patologia , Masculino , Mutagênese/genética , Fenótipo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , gama-Glutamiltransferase/metabolismoRESUMO
OBJECTIVES: To define the ranges of biochemical markers during hypoglycemia for the diagnosis of congenital hyperinsulinism (CHI), using high sensitivity insulin assays. SUBJECTS: A total of 298 patients with CHI and 58 control patients with non-hyperinsulinemic hypoglycemia, who were diagnosed after 2007. METHODS: The levels of biochemical markers (glucose, insulin, ß-hydroxybutyrate [BHB], free fatty acids [FFA], lactate, ammonia) at the time of hypoglycemia were analyzed along with the maximal glucose infusion rate (GIR) to maintain euglycemia and clinical outcomes. RESULTS: Median levels of blood glucose in patients with CHI and in controls were 30 and 46 mg/dL, while insulin levels were 9.90 and undetectable (<.5) µU/mL, respectively. Similarly, median levels of BHB were 17.5 and 3745 µmol/L, and those of FFA were 270.5 and 2660 µmol/L, respectively. For patients after 5 months, cutoffs of insulin >1.25 µU/mL, BHB < 2000 µmol/L, and FFA < 1248 µmol/L predicted CHI with sensitivities of 97.5, 96.2, and 95.2% and specificities of 84.2, 89.3, and 92.3%, respectively. Maximal GIR in the CHI groups tended to decrease with age. In addition, decreased gestational age, low birth weight, and elevated lactate at hypoglycemia were significantly more common in patients who were off treatment within 100 days without pancreatectomy. CONCLUSIONS: After introduction of high-sensitive assays, the diagnostic value of insulin was improved, allowing for more efficient cutoffs to be set for diagnosis of CHI. Premature birth, low birth weight and elevated lactate might be helpful in predicting early remission of hypoglycemia.
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Hiperinsulinismo Congênito/diagnóstico , Hiperamonemia/etiologia , Hiperlactatemia/etiologia , Hipoglicemia/etiologia , Ácido 3-Hidroxibutírico/sangue , Biomarcadores/sangue , Criança , Pré-Escolar , Hiperinsulinismo Congênito/sangue , Hiperinsulinismo Congênito/etiologia , Hiperinsulinismo Congênito/fisiopatologia , Ácidos Graxos não Esterificados/sangue , Feminino , Inquéritos Epidemiológicos , Hospitais Gerais , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Japão , Masculino , Nascimento Prematuro/fisiopatologia , Encaminhamento e Consulta , Remissão Espontânea , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Growth hormone (GH) replacement therapy improves hypercholesterolemia in patients with GH deficiency, suggesting that GH modulates cholesterol metabolism. OBJECTIVES: We examined GH effects on lipid profiles and cholesterol-related markers reflecting hepatic and cerebral cholesterol metabolism in small-for-gestational age (SGA) children without catch-up growth. METHODS: This study examined SGA children without catch-up growth (n = 22) and healthy children (controls, n = 11). Based on parents' choice, 11 SGA children received GH at 0.23 to 0.25 mg/kg/d for 6 months, and at 0.34 to 0.36 mg/kg/d for the subsequent 6 months (GH (+) group). The other SGA children received no GH (GH (-) group, n = 11). We ascertained baseline and posttreatment lipid profiles and cholesterol-related markers reflecting hepatic and cerebral cholesterol metabolism. RESULTS: Baseline lipid profiles of SGA children and controls were similar. Serum 24S-hydroxycholesterol (marker for cerebral cholesterol metabolism) concentration was 19% lower in SGA children than in controls (P < .05). Compared with baseline, the GH (+) group low-density lipoprotein-cholesterol concentration had decreased by 6.6% during 6 months and 8.8% during 12 months (P < .01), whereas the high-density lipoprotein-cholesterol concentration had increased by 1.7% (P = .07) and 3.3% (P < .01). Serum 7α-hydroxycholesterol (marker for hepatic cholesterol elimination) concentration had increased by 34% at 6 months and 35% at 12 months (P < .01). In addition, 24S-hydroxycholesterol increased by 25% and 26% (P < .001). No marker for cholesterol synthesis or absorption changed. The GH (-) group lipid profiles and oxysterols remained unchanged during the observation period. CONCLUSION: GH activates hepatic and cerebral cholesterol metabolism in SGA children without catch-up growth.
Assuntos
Encéfalo/efeitos dos fármacos , Colesterol/metabolismo , Hormônio do Crescimento Humano/farmacologia , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Recém-Nascido Pequeno para a Idade Gestacional/metabolismo , Fígado/efeitos dos fármacos , Absorção Fisico-Química/efeitos dos fármacos , Apolipoproteínas/metabolismo , Estatura/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Criança , Pré-Escolar , Colesterol/biossíntese , Feminino , Glucose/metabolismo , Humanos , Fígado/metabolismo , MasculinoRESUMO
Citrin deficiency causes adult-onset type II citrullinemia (CTLN-2), which later manifests as severe liver steatosis and life-threatening encephalopathy. Long-standing energy deficit of the liver and brain may predispose ones to CTLN-2. Here, we compared the energy-driving tricarboxylic acid (TCA) cycle and fatty acid ß-oxidation cycle between 22 citrin-deficient children (age, 3-13years) with normal liver functions and 37 healthy controls (age, 5-13years). TCA cycle analysis showed that basal plasma citrate and α-ketoglutarate levels were significantly higher in the affected than the control group (p<0.01). Conversely, basal plasma fumarate and malate levels were significantly lower than those for the control (p<0.001). The plasma level of 3-OH-butyrate derived from fatty acid ß-oxidation was significantly higher in the affected group (p<0.01). Ten patients underwent sodium pyruvate therapy. However, this therapy did not correct or attenuate such deviations in both cycles. Sodium pyruvate therapy significantly increased fasting insulin secretion (p<0.01); the fasting sugar level remained unchanged. Our results suggest that citrin-deficient children show considerable deviations of TCA cycle metabolite profiles that are resistant to sodium pyruvate treatment. Thus, long-standing and considerable TCA cycle dysfunction might be a pivotal metabolic background of CTLN-2 development.
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Ciclo do Ácido Cítrico , Citrulinemia/tratamento farmacológico , Citrulinemia/metabolismo , Ácidos Graxos/metabolismo , Piruvatos/administração & dosagem , Adolescente , Criança , Pré-Escolar , Ácido Cítrico/sangue , Ciclo do Ácido Cítrico/efeitos dos fármacos , Feminino , Fumaratos/sangue , Humanos , Ácidos Cetoglutáricos/sangue , Malatos/sangue , Masculino , Estresse Oxidativo/efeitos dos fármacos , Piruvatos/farmacologia , Resultado do TratamentoRESUMO
Glycosylation is involved in various pathophysiological conditions. N-Acetylglucosaminyltransferase V (GnT-V), catalyzing ß1-6 branching in asparagine-linked oligosaccharides, is one of the most important glycosyltransferases involved in cancer and the immune system. Recent findings indicate that aberrant N-glycan structure can modify lipid metabolism. In this study, we investigated the effects of aberrant glycosylation by GnT-V on high-density lipoprotein cholesterol (HDL) assembly. We used GnT-V transgenic (Tg) mice and GnT-V Hep3B cell (human hepatoma cell line) transfectants. The study also included 96 patients who underwent medical health check-ups. Total serum cholesterol levels, particularly HDL-cholesterol (HDL-C) levels, were significantly increased in Tg vs. wild-type (WT) mice. Hepatic expression of apolipoprotein AI (ApoAI) and ATP-binding cassette subfamily A member 1 (ABCA1), two important factors in HDL assembly, were higher in Tg mice compared with WT mice. ApoAI and ABCA1 were also significantly elevated in GnT-V transfectants compared with mock-transfected cells. Moreover, ApoAI protein in the cultured media of GnT-V transfectants was significantly increased. Finally, we found a strong correlation between serum GnT-V activity and HDL-C concentration in human subjects. Multivariate logistic analyses demonstrated that GnT-V activity was an independent and significant determinant for serum HDL-C levels even adjusted with age and gender differences. Further analyses represented that serum GnT-V activity had strong correlation especially with the large-size HDL particle concentration. These findings indicate that enhanced hepatic GnT-V activity accelerated HDL assembly and could be a novel mechanism for HDL synthesis.
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Lipoproteínas HDL/metabolismo , Fígado/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Apolipoproteínas A/metabolismo , Linhagem Celular Tumoral , Feminino , Glicosilação , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , FosforilaçãoRESUMO
AIM: Benign recurrent intrahepatic cholestasis type 2 (BRIC2) is caused by mutations in ABCB11, a gene encoding the bile salt export pump (BSEP) that mediates biliary bile salt secretion, and presents with repeated intermittent cholestasis with refractory itching. Currently, no effective medical therapy has been established. We previously provided experimental and clinical evidence suggesting the therapeutic potential of 4-phenylbutyrate (4PB) for the cholestatic attacks of BRIC2. METHODS: After examining the potential therapeutic use of 4PB treatment by in vitro studies, a patient with BRIC2 was treated p.o. with 4PB at gradually increasing doses (200, 350, and 500 mg/kg per day) for 4 months. Biochemical, histological and clinical data were collected. RESULTS: The patient was diagnosed with BRIC2 because he had non-synonymous mutations (c.1211A>G [p.D404G] and 1331T>C [p.V444A]) in ABCB11, reduced hepatocanalicular expression of BSEP and low biliary bile salt concentrations. In vitro analysis showed that 4PB treatment partially restored the decreased expression of BSEP caused by p.D404G mutation. During the first 2 months of 4PB therapy at 200 and 350 mg/kg per day, the patient had no relief from his symptoms. No beneficial effect was observed after additional treatment with bilirubin absorption and endoscopic nasobiliary drainage. However, after starting treatment at a dose of 500 mg/kg per day, the patient's liver function tests and intractable itching were markedly improved. No apparent side-effects were observed during or after 4PB therapy. The symptoms relapsed within 1.5 months after cessation of 4PB therapy. CONCLUSION: 4PB therapy would have a therapeutic effect on the cholestatic attacks of BRIC2.
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CONTEXT: GH activates the expression of low-density lipoprotein (LDL) receptors, leading to decreased LDL-cholesterol (LDL-C). Apolipoprotein (apo) E4 carriers suppress LDL receptor expression, rendering high LDL-C concentrations. OBJECTIVES: We examined whether GH-deficient children carrying apoE4 exhibited a greater reduction in LDL-C after GH replacement therapy. DESIGN AND SETTING: We determined lipoprotein profiles after 0, 4, and 12 months of GH treatment in children with an idiopathic GH deficiency. We compared the effects of GH treatment on LDL-C by apoE phenotype. SUBJECTS: In total, 66 children with idiopathic GH deficiency and 89 healthy children were classified into subgroups according to apoE phenotype. INTERVENTION: The intervention included GH replacement therapy for 12 months. MAIN OUTCOME MEASURES: The relationship between apoE phenotype and reduced LDL-C induced by GH treatment was measured. RESULTS: Concentrations of LDL-C and apoB were highest in the apoE4/3 group (n = 13), second highest in the apoE3/3 group (n = 46), and lowest in the apoE3/2 group (n = 7), whereas apoE concentrations were highest in the apoE3/2 group and lowest in the apoE4/3 group. The apoE4/3 group had significantly reduced LDL-C and apoB concentrations at months 4 and 12, whereas the apoE3/3 and apoE3/2 groups showed no changes. LDL-C concentrations did not differ among the three groups after 12 months. The trend in apoE concentration did not change among the groups. CONCLUSIONS: Children with a GH deficiency carrying apoE4 had higher baseline LDL-C concentrations and experienced a greater reduction in LDL-C after GH replacement therapy than those without apoE4.
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Apolipoproteína E4/genética , LDL-Colesterol/sangue , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Hipopituitarismo/tratamento farmacológico , Criança , Pré-Escolar , Feminino , Hormônio do Crescimento Humano/deficiência , Humanos , Hipopituitarismo/sangue , Hipopituitarismo/genética , Masculino , Resultado do TratamentoRESUMO
It is of importance to clarify pathophysiology of diabetic heart diseases such as heart failure and coronary artery disease. We reported a novel clinical phenotype called triglyceride deposit cardiomyovasculopathy (TGCV), showing aberrant TG accumulation in both coronary arteries and myocardium, in a cardiac transplant recipient. Here, we examined autopsied diabetics for TG deposition in cardiovasculature. Consecutive series of hearts from advanced diabetes mellitus (DM) subjects (DM group: DMG, n = 20) and those from age- and sex-matched non-diabetic controls (non DM group: NDMG, n = 20) were examined. The diagnostic criteria of 'advanced DM' was made based on 2014 Clinical Practice Recommendations proposed by the American Diabetes Association. The mean duration of DM was 15.8 years. All DMG suffered from heart diseases including coronary artery diseases and 14 subjects had multi-vessel disease. Tissue TG contents were measured biochemically. Coronary arterial TG contents was significantly higher in DMG compared with NDMG. Spatial distribution of TG in transverse sections of coronary arteries showed TG deposition mainly in smooth muscle cells by Imaging Mass Spectrometry. Abundant TG deposition in coronary artery might be associated with advanced DM.
Assuntos
Doença das Coronárias/metabolismo , Vasos Coronários/metabolismo , Complicações do Diabetes/metabolismo , Diabetes Mellitus/metabolismo , Triglicerídeos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença das Coronárias/complicações , Doença das Coronárias/patologia , Doença das Coronárias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Liso/patologiaRESUMO
BACKGROUND: Progressive familial intrahepatic cholestasis type 1 (PFIC1), an inherited liver disease caused by mutations in ATP8B1, progresses to severe cholestasis with a sustained intractable itch. Currently, no effective therapy has been established for PFIC1. Decreased function of the bile salt export pump (BSEP) in hepatocytes is suggested to be responsible for the severe cholestasis observed in PFIC1. We found a previously unidentified pharmacological effect of 4-phenylbutyrate (4PB) that increases the expression and function of BSEP. Here, we tested 4PB therapy in three patients with PFIC1. METHODS: The therapeutic potency of 4PB in these patients was tested by oral administration of this drug with gradually increasing dosage (200, 350, and 500 mg/kg/day) for 6 months. Biochemical, histological, and clinical data were collected. RESULTS: 4PB therapy had no beneficial effect on the patients' liver functions, as assessed by biochemical and histological analyses, despite an increase in hepatic BSEP expression. However, therapy with 4PB at a dosage of 350 or 500 mg/kg/day significantly relieved the intractable itch. Serum levels of potential pruritogens in cholestasis were much higher than the reference ranges during the 4PB therapy. CONCLUSIONS: 4PB therapy may be a new medication for patients with intractable cholestatic pruritus and may improve quality of life for patients and their families.
Assuntos
Colestase Intra-Hepática/complicações , Doenças Genéticas Inatas/complicações , Fenilbutiratos/uso terapêutico , Prurido/tratamento farmacológico , Administração Oral , Adolescente , Criança , Pré-Escolar , Colestase Intra-Hepática/genética , Colestase Intra-Hepática/fisiopatologia , Progressão da Doença , Relação Dose-Resposta a Droga , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/fisiopatologia , Humanos , Fenilbutiratos/administração & dosagem , Prurido/etiologiaRESUMO
OBJECTIVE: Although starvation is associated with high in-hospital mortality, its related cardiac complications are not sufficiently understood. The aim of this study was to determine the clinical course and pathogenesis of cardiac complications in malnourished patients. METHODS: We reviewed three cases of hypoglycemia and hypotriglyceridemia with cardiac complications in starvation. RESULTS: This report concerns three patients, respectively suffering from anorexia nervosa, esophageal carcinoma, and Parkinson's disease. Their ages ranged from 18 to 70 y, body mass index was 11.5 ± 1.5 kg/m2 (mean ± SD), and the main symptom was coma. The average blood glucose level was 15.7 ± 7.8 mg/dL without any history of insulin use or diabetes mellitus. In all cases, hypoglycemia was refractory and repetitive so that continuous glucose administration was required to maintain euglycemia. Serum triglyceride and non-esterified fatty acid levels were also very low (7 ± 4 mg/dL and 10 ± 9.1 µEq/L, respectively). Levels of serum potassium, phosphate, and magnesium were almost normal at admission. The main cardiac complications included Takotsubo cardiomyopathy and cardiac arrest. All patients survived as a result of intensive treatment. CONCLUSIONS: Repetitive severe hypoglycemia without known background causes should be viewed as an important sign. Once this occurs, the administration of a much higher caloric input than usual accompanied by intensive monitoring will be required to maintain appropriate glucose levels. The early identification of such patients seems to be essential to reduce the high risk for cardiac complications during starvation and refeeding.