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1.
J Hum Genet ; 69(5): 215-222, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38409496

RESUMEN

Although the molecular mechanisms underlying congenital heart disease (CHD) remain poorly understood, recent advances in genetic analysis have facilitated the exploration of causative genes for CHD. We reported that the pathogenic variant c.1617del of TMEM260, which encodes a transmembrane protein, is highly associated with CHD, specifically persistent truncus arteriosus (PTA), the most severe cardiac outflow tract (OFT) defect. Using whole-exome sequencing, the c.1617del variant was identified in two siblings with PTA in a Japanese family and in three of the 26 DNAs obtained from Japanese individuals with PTA. The c.1617del of TMEM260 has been found only in East Asians, especially Japanese and Korean populations, and the frequency of this variant in PTA is estimated to be next to that of the 22q11.2 deletion, the most well-known genetic cause of PTA. Phenotype of patients with c.1617del appears to be predominantly in the heart, although TMEM260 is responsible for structural heart defects and renal anomalies syndrome (SHDRA). The mouse TMEM260 variant (p.W535Cfs*56), synonymous with the human variant (p.W539Cfs*9), exhibited truncation and downregulation by western blotting, and aggregation by immunocytochemistry. In situ hybridization demonstrated that Tmem260 is expressed ubiquitously during embryogenesis, including in the development of cardiac OFT implicated in PTA. This expression may be regulated by a ~ 0.8 kb genomic region in intron 3 of Tmem260 that includes multiple highly conserved binding sites for essential cardiac transcription factors, thus revealing that the c.1617del variant of TMEM260 is the major single-gene variant responsible for PTA in the Japanese population.


Asunto(s)
Cardiopatías Congénitas , Proteínas de la Membrana , Animales , Femenino , Humanos , Masculino , Ratones , Pueblo Asiatico/genética , Pueblos del Este de Asia , Secuenciación del Exoma , Predisposición Genética a la Enfermedad , Cardiopatías Congénitas/genética , Cardiopatías Congénitas/patología , Japón , Proteínas de la Membrana/genética , Linaje , Fenotipo
2.
Rinsho Ketsueki ; 65(2): 90-94, 2024.
Artículo en Japonés | MEDLINE | ID: mdl-38448004

RESUMEN

A 62-year-old woman was diagnosed as a hemophilia A carrier (factor VIII activity 35%) on preoperative examination of an ovarian tumor. A total of 35,600 units of recombinant factor VIII products was administered perioperatively. On postoperative day 95, a subcutaneous hematoma formed and immunosuppressive therapy with prednisolone was started based on an APTT of 66 seconds, factor VIII (FVIII) activity of 3%, and FVIII inhibitor of 1 BU/ml. During this treatment, the patient was hospitalized due to ankle joint bleeds and required hemostatic treatment, but the inhibitor disappeared and FVIII activity recovered to 30% after postoperative day 438 with cyclophosphamide. F8 analysis revealed the patient carried a heterozygosity of p.Arg391Cys, which has previously been categorized as cross-reacting material (CRM)-positive severe hemophilia A. No high-risk mutations for inhibitor development were found. We also report the results of a desmopressin acetate hydrate test administered to the patient to prepare for future treatment in case of hemorrhage, since high-dose FVIII administration may have been a factor in inhibitor development.


Asunto(s)
Hemofilia A , Hemostáticos , Femenino , Humanos , Persona de Mediana Edad , Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Hemostáticos/uso terapéutico , Hemartrosis , Terapia de Inmunosupresión
3.
FASEB J ; 33(4): 5300-5311, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30681884

RESUMEN

Transcriptional and epigenetic regulation is fundamentally involved in initiating and maintaining progression of cellular differentiation. The 2 types of thermogenic adipocytes, brown and beige, are thought to be of different origins but share functionally similar phenotypes. Here, we report that lysine-specific demethylase 2 (LSD2) regulates the expression of genes associated with lineage identity during the differentiation of brown and beige adipogenic progenitors in mice. In HB2 mouse brown preadipocytes, short hairpin RNA-mediated knockdown (KD) of LSD2 impaired formation of lipid droplet-containing adipocytes and down-regulated brown adipogenesis-associated genes. Transcriptomic analysis revealed that myogenesis-associated genes were up-regulated in LSD2-KD cells under adipogenic induction. In addition, loss of LSD2 during later phases of differentiation had no obvious influence on adipogenic traits, suggesting that LSD2 functions during earlier phases of brown adipocyte differentiation. Using adipogenic cells from the brown adipose tissues of LSD2-knockout (KO) mice, we found reduced expression of brown adipogenesis genes, whereas myogenesis genes were not affected. In contrast, when LSD2-KO cells from inguinal white adipose tissues were subjected to beige induction, these cells showed a dramatic rise in myogenic gene expression. Collectively, these results suggest that LSD2 regulates distinct sets of genes during brown and beige adipocyte formation.-Takase, R., Hino, S., Nagaoka, K., Anan, K., Kohrogi, K., Araki, H., Hino, Y., Sakamoto, A., Nicholson, T. B., Chen, T., Nakao, M. Lysine-specific demethylase-2 is distinctively involved in brown and beige adipogenic differentiation.


Asunto(s)
Tejido Adiposo Pardo/citología , Tejido Adiposo Pardo/metabolismo , Histona Demetilasas/metabolismo , ARN Interferente Pequeño/metabolismo , Adipogénesis/genética , Adipogénesis/fisiología , Animales , Western Blotting , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Células Cultivadas , Inmunoprecipitación de Cromatina , Femenino , Histona Demetilasas/genética , Lentivirus/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , PPAR gamma/metabolismo , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
J Interv Cardiol ; 2020: 5147193, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32802008

RESUMEN

BACKGROUND: Transcatheter closure of patent ductus arteriosus (TC-PDA), conventionally guided by aortography, has become the standard treatment of this disease. The purposes of this study were to evaluate whether intracardiac echocardiography (ICE) may be used for measuring PDA size and be used as a guide for TC-PDA. METHODS: This study had 2 phases. In phase 1, we compared the measurements of PDA size: pulmonary artery side diameter (PA-D), length, and aortic side diameter (Ao-D) of PDA, as measured by ICE with those measured by aortography or cardiac computed tomography (AoG/CCT) in 23 patients who underwent TC-PDA. In phase 2, we compared the demographics, fluoroscopic time, contrast volume, and complications of the TC-PDAs between 10 adult patients with ICE guidance and 16 without it. RESULTS: In phase 1, we found great correlation and agreement between ICE and AoG/CCT in PA-D (r = 0.985, bias -0.077 to 0.224), but moderate to poor correlation and agreement in length (r = 0.653, bias -0.491 to 3.065) and Ao-D (r = 0.704, bias 0.738 to 4.732), respectively. Nevertheless, all patients underwent successful TC-PDA with ICE guidance that allowed us to continuously monitor the whole process. In phase 2, TC-PDA required a significantly lower contrast volume with ICE guidance than without it, and there was no significant difference in the remaining variables between the 2 groups. CONCLUSION: ICE is comparable to AoG/CCT in providing accurate PA-D of the PDA and may be a safe alternative to guide TC-PDA as compared to conventional aortography.


Asunto(s)
Cateterismo Cardíaco , Conducto Arterioso Permeable/diagnóstico por imagen , Conducto Arterioso Permeable/cirugía , Ecocardiografía , Ultrasonografía Intervencional , Adulto , Aortografía , Preescolar , Femenino , Fluoroscopía , Humanos , Lactante , Masculino , Arteria Pulmonar , Resultado del Tratamiento
5.
Nucleic Acids Res ; 46(11): 5441-5454, 2018 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-29618057

RESUMEN

The metabolic properties of cells are formed under the influence of environmental factors such as nutrients and hormones. Although such a metabolic program is likely initiated through epigenetic mechanisms, the direct links between metabolic cues and activities of chromatin modifiers remain largely unknown. In this study, we show that lysine-specific demethylase-1 (LSD1) controls the metabolic program in myogenic differentiation, under the action of catabolic hormone, glucocorticoids. By using transcriptomic and epigenomic approaches, we revealed that LSD1 bound to oxidative metabolism and slow-twitch myosin genes, and repressed their expression. Consistent with this, loss of LSD1 activity during differentiation enhanced the oxidative capacity of myotubes. By testing the effects of various hormones, we found that LSD1 levels were decreased by treatment with the glucocorticoid dexamethasone (Dex) in cultured myoblasts and in skeletal muscle from mice. Mechanistically, glucocorticoid signaling induced expression of a ubiquitin E3 ligase, JADE-2, which was responsible for proteasomal degradation of LSD1. Consequently, in differentiating myoblasts, chemical inhibition of LSD1, in combination with Dex treatment, synergistically de-repressed oxidative metabolism genes, concomitant with increased histone H3 lysine 4 methylation at these loci. These findings demonstrated that LSD1 serves as an epigenetic regulator linking glucocorticoid action to metabolic programming during myogenic differentiation.


Asunto(s)
Dexametasona/farmacología , Glucocorticoides/farmacología , Histona Demetilasas/metabolismo , Desarrollo de Músculos/genética , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/citología , Animales , Diferenciación Celular/genética , Línea Celular Tumoral , Histona Demetilasas/antagonistas & inhibidores , Histonas/metabolismo , Masculino , Metilación , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Oxidación-Reducción , Ubiquitina-Proteína Ligasas/metabolismo
7.
Gen Comp Endocrinol ; 260: 58-66, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29277418

RESUMEN

Epidemiological research has suggested that birth weights are correlated with adult leg lengths. However, the relationship between prenatal undernutrition (UN) and postnatal leg growth remains controversial. We investigated the effects of UN during early pregnancy on postnatal hindlimb growth and determined whether early embryonic malnutrition affects the functions of postnatal chondrocytes in rats. Undernourished Wistar dams were fed 40% of the daily intake of rats in the control groups from gestational days 5.5-11.5, and femurs, tibias, and trunks or spinal columns were morphologically measured at birth and at 16 weeks of age in control and undernourished offspring of both sexes. We evaluated cell proliferation and differentiation of cultured chondrocytes derived from neonatal tibias of female offspring and determined chondrocyte-related gene expression levels in neonatal epiphysis and embryonic limb buds. Tibial lengths of undernourished female, but not male, offspring were longer at birth and shorter at 16 weeks of age (p < .05) compared with those of control rats. In chondrocyte culture studies, stimulating effects of IGF-1 on cell proliferation (p < .01) were significantly decreased and levels of type II collagen were lower in female undernourished offspring (p < .05). These phenomena were accompanied by decreased expression levels of Col2a1 and Igf1r and increased expression levels of Fgfr3 (p < .05), which might be attributable to the decreased expression of specificity protein 1 (p < .05), a key transactivator of Col2a1 and Igf1r. In conclusion, UN stress during early pregnancy reduces postnatal tibial growth in female offspring by altering the function of chondrocytes, likely reflecting altered expression of gene transactivators.


Asunto(s)
Desarrollo Óseo/fisiología , Condrogénesis/fisiología , Desnutrición/fisiopatología , Fenómenos Fisiologicos Nutricionales Maternos , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Tibia/crecimiento & desarrollo , Animales , Animales Recién Nacidos , Femenino , Retardo del Crecimiento Fetal/etiología , Edad Gestacional , Masculino , Desnutrición/complicaciones , Embarazo , Ratas , Ratas Wistar
8.
Elife ; 122023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36695573

RESUMEN

Skeletal muscle exhibits remarkable plasticity in response to environmental cues, with stress-dependent effects on the fast-twitch and slow-twitch fibers. Although stress-induced gene expression underlies environmental adaptation, it is unclear how transcriptional and epigenetic factors regulate fiber type-specific responses in the muscle. Here, we show that flavin-dependent lysine-specific demethylase-1 (LSD1) differentially controls responses to glucocorticoid and exercise in postnatal skeletal muscle. Using skeletal muscle-specific LSD1-knockout mice and in vitro approaches, we found that LSD1 loss exacerbated glucocorticoid-induced atrophy in the fast fiber-dominant muscles, with reduced nuclear retention of Foxk1, an anti-autophagic transcription factor. Furthermore, LSD1 depletion enhanced endurance exercise-induced hypertrophy in the slow fiber-dominant muscles, by induced expression of ERRγ, a transcription factor that promotes oxidative metabolism genes. Thus, LSD1 serves as an 'epigenetic barrier' that optimizes fiber type-specific responses and muscle mass under the stress conditions. Our results uncover that LSD1 modulators provide emerging therapeutic and preventive strategies against stress-induced myopathies such as sarcopenia, cachexia, and disuse atrophy.


Asunto(s)
Glucocorticoides , Enfermedades Musculares , Ratones , Animales , Glucocorticoides/metabolismo , Músculo Esquelético/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Factores de Transcripción/metabolismo , Histona Demetilasas/genética , Histona Demetilasas/metabolismo
9.
Am J Ophthalmol Case Rep ; 24: 101213, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34632159

RESUMEN

PURPOSE: We describe the ocular findings in a patient with Alagille syndrome, included those obtained with ultra-widefield and anterior-segment optical coherence tomography (AS-OCT) imaging. OBSERVATIONS: A previously asymptomatic 29-year-old woman with a heterozygous pathogenic variant in the JAG1 gene was referred for an ophthalmic evaluation. The ocular abnormalities included bilateral posterior embryotoxon, iris atrophy, retinal pigmentary changes in the peripheral and peripapillary regions, and optic disc elevation. Ultra-widefield OCT showed bilateral retinal thinning with increased choroidal hyperreflectivity in the areas of peripheral retinopathy and optic disc elevation. AS-OCT confirmed bilateral iris atrophy. CONCLUSIONS AND IMPORTANCE: The ocular abnormalities observed in the present case represent clinical features characteristic of Alagille syndrome. Both ultra-widefield and AS-OCT were useful for assessing the ocular abnormalities in Alagille syndrome.

10.
Front Immunol ; 12: 687280, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34122451

RESUMEN

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare monogenic autosomal recessive disorder caused by mutation in the autoimmune regulator (AIRE) gene. Patients usually are diagnosed at ages between 5 and 15 years when they show 3 or more manifestations, most typically mucocutaneous candidiasis, Addison's disease, and hypoparathyroidism. APECED-associated hepatitis (APAH) develops in only 10% to 40% of patients, with severity varying from subclinical chronic active hepatitis to potentially fatal acute liver failure (ALF). Ocular abnormalities are fairly common, most often keratopathy but sometimes retinopathy. Here we report a 2-year-old Japanese girl with an AIRE gene mutation who developed APAH with ALF, preceded by autoimmune retinopathy associated with anti-recoverin antibody before major symptoms suggested a diagnosis of APECED. Intravenous pulse methylprednisolone therapy followed by a corticosteroid combined with azathioprine treatment resolved ALF and achieved control of APAH. To our knowledge, our patient is the youngest reported to have ALF resulting from an AIRE gene mutation. Pulse methylprednisolone induction therapy followed by treatment with corticosteroid plus azathioprine may well be effective in other children with APAH and AIRE gene mutations.


Asunto(s)
Corticoesteroides/administración & dosificación , Enfermedades Autoinmunes/tratamiento farmacológico , Fallo Hepático Agudo/tratamiento farmacológico , Metilprednisolona/administración & dosificación , Mutación , Poliendocrinopatías Autoinmunes/tratamiento farmacológico , Enfermedades de la Retina/tratamiento farmacológico , Factores de Transcripción/genética , Administración Intravenosa , Autoanticuerpos/sangre , Enfermedades Autoinmunes/diagnóstico , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/inmunología , Azatioprina/administración & dosificación , Preescolar , Quimioterapia Combinada , Femenino , Predisposición Genética a la Enfermedad , Humanos , Inmunosupresores/administración & dosificación , Fallo Hepático Agudo/diagnóstico , Fallo Hepático Agudo/genética , Fallo Hepático Agudo/inmunología , Fenotipo , Poliendocrinopatías Autoinmunes/diagnóstico , Poliendocrinopatías Autoinmunes/genética , Poliendocrinopatías Autoinmunes/inmunología , Quimioterapia por Pulso , Recoverina/inmunología , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/genética , Enfermedades de la Retina/inmunología , Resultado del Tratamiento , Proteína AIRE
11.
Blood Adv ; 5(9): 2305-2318, 2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33929501

RESUMEN

Acute myeloid leukemia (AML) is a heterogenous malignancy characterized by distinct lineage subtypes and various genetic/epigenetic alterations. As with other neoplasms, AML cells have well-known aerobic glycolysis, but metabolic variations depending on cellular lineages also exist. Lysine-specific demethylase-1 (LSD1) has been reported to be crucial for human leukemogenesis, which is currently one of the emerging therapeutic targets. However, metabolic roles of LSD1 and lineage-dependent factors remain to be elucidated in AML cells. Here, we show that LSD1 directs a hematopoietic lineage-specific metabolic program in AML subtypes. Erythroid leukemia (EL) cells particularly showed activated glycolysis and high expression of LSD1 in both AML cell lines and clinical samples. Transcriptome, chromatin immunoprecipitation-sequencing, and metabolomic analyses revealed that LSD1 was essential not only for glycolysis but also for heme synthesis, the most characteristic metabolic pathway of erythroid origin. Notably, LSD1 stabilized the erythroid transcription factor GATA1, which directly enhanced the expression of glycolysis and heme synthesis genes. In contrast, LSD1 epigenetically downregulated the granulo-monocytic transcription factor C/EBPα. Thus, the use of LSD1 knockdown or chemical inhibitor dominated C/EBPα instead of GATA1 in EL cells, resulting in metabolic shifts and growth arrest. Furthermore, GATA1 suppressed the gene encoding C/EBPα that then acted as a repressor of GATA1 target genes. Collectively, we conclude that LSD1 shapes metabolic phenotypes in EL cells by balancing these lineage-specific transcription factors and that LSD1 inhibitors pharmacologically cause lineage-dependent metabolic remodeling.


Asunto(s)
Leucemia Eritroblástica Aguda , Proteína alfa Potenciadora de Unión a CCAAT , Factor de Transcripción GATA1/genética , Histona Demetilasas/genética , Humanos , Leucemia Eritroblástica Aguda/genética , Proteínas Proto-Oncogénicas , Factores de Transcripción
12.
Neurosci Res ; 63(1): 66-71, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19010360

RESUMEN

We examined the effects of the odors from mother's milk, other mother's milk and formula milk on pain responses in newborns undergoing routine heelsticks. Forty-eight healthy infants were assigned to four groups, an own mother's breast milk odor group (Own MM), another mother's breast milk odor group (Other MM), a formula milk odor group (Formula M) and a control group. To assess infant distress in response to the heelsticks, their crying, grimacing and motor activities were recorded during the experiment as behavioral indices of the pain response. After the heelstick, the behavioral indices of the Own MM group were lower than those of other groups. By contrast, the Other MM and Formula M groups showed no significant changes compared with the Control group. We also measured salivary cortisol concentration as a biochemical index in Control and Own MM infants before and after heelstick. After the heelstick, the level of salivary cortisol was significantly increased in Control infants, but not in Own MM infants. These results suggest that pain is relieved in human newborns when they are exposed to odors from their mother's milk.


Asunto(s)
Lactancia Materna/psicología , Leche Humana/química , Odorantes , Dolor/psicología , Olfato/fisiología , Estrés Psicológico/psicología , Ansiedad/fisiopatología , Ansiedad/psicología , Llanto/fisiología , Llanto/psicología , Expresión Facial , Femenino , Humanos , Hidrocortisona/antagonistas & inhibidores , Hidrocortisona/metabolismo , Conducta del Lactante/fisiología , Conducta del Lactante/psicología , Recién Nacido , Masculino , Leche Humana/fisiología , Relaciones Madre-Hijo , Dolor/fisiopatología , Dimensión del Dolor , Estrés Psicológico/fisiopatología
13.
Cancer Res ; 75(7): 1445-56, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25649769

RESUMEN

The hallmark of most cancer cells is the metabolic shift from mitochondrial to glycolytic metabolism for adapting to the surrounding environment. Although epigenetic modification is intimately linked to cancer, the molecular mechanism, by which epigenetic factors regulate cancer metabolism, is poorly understood. Here, we show that lysine-specific demethylase-1 (LSD1, KDM1A) has an essential role in maintaining the metabolic shift in human hepatocellular carcinoma cells. Inhibition of LSD1 reduced glucose uptake and glycolytic activity, with a concurrent activation of mitochondrial respiration. These metabolic changes coexisted with the inactivation of the hypoxia-inducible factor HIF1α, resulting in a decreased expression of GLUT1 and glycolytic enzymes. In contrast, during LSD1 inhibition, a set of mitochondrial metabolism genes was activated with the concomitant increase of methylated histone H3 at lysine 4 in the promoter regions. Consistently, both LSD1 and GLUT1 were significantly overexpressed in carcinoma tissues. These findings demonstrate the epigenetic plasticity of cancer cell metabolism, which involves an LSD1-mediated mechanism.


Asunto(s)
Carcinoma Hepatocelular/enzimología , Histona Demetilasas/fisiología , Neoplasias Hepáticas/enzimología , Mitocondrias Hepáticas/enzimología , Animales , Carcinoma Hepatocelular/patología , Expresión Génica , Transportador de Glucosa de Tipo 1/genética , Transportador de Glucosa de Tipo 1/metabolismo , Glucólisis , Células Hep G2 , Histonas/metabolismo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/fisiología , Neoplasias Hepáticas/patología , Metilación , Ratones SCID , Trasplante de Neoplasias , Procesamiento Proteico-Postraduccional , Carga Tumoral
14.
Mol Cell Biol ; 35(7): 1068-80, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25624347

RESUMEN

Cells link environmental fluctuations, such as nutrition, to metabolic remodeling. Epigenetic factors are thought to be involved in such cellular processes, but the molecular basis remains unclear. Here we report that the lysine-specific demethylase 2 (LSD2) suppresses the flux and metabolism of lipids to maintain the energy balance in hepatic cells. Using transcriptome and chromatin immunoprecipitation-sequencing analyses, we revealed that LSD2 represses the genes involved in lipid influx and metabolism through demethylation of histone H3K4. Selective recruitment of LSD2 at lipid metabolism gene loci was mediated in part by a stress-responsive transcription factor, c-Jun. Intriguingly, LSD2 depletion increased the intracellular levels of many lipid metabolites, which was accompanied by an increased susceptibility to toxic cell damage in response to fatty acid exposure. Our data demonstrate that LSD2 maintains metabolic plasticity under fluctuating environment in hepatocytes by mediating the cross talk between the epigenome and metabolism.


Asunto(s)
Regulación hacia Abajo , Hepatocitos/metabolismo , Histona Demetilasas/metabolismo , Metabolismo de los Lípidos , Lípidos/genética , Animales , Células Hep G2 , Histonas/metabolismo , Humanos , Hígado/metabolismo , Lisina/metabolismo , Masculino , Metilación , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-jun/metabolismo
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