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1.
Jpn J Infect Dis ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38945858

RESUMEN

The widespread prevalence of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli limits treatment options and is a worldwide problem. The aim of this study was to investigate the antimicrobial susceptibility and ESBL-type of 204 strains of CTX-M-type ESBLs-producing E. coli isolated from 2011 to 2017 in the Chubu region of Japan. Minimal inhibitory concentrations were determined in accordance with the guidelines of the Clinical and Laboratory Standards Institute. Genes encoding CTX-M group ß-lactamases were detected by PCR amplification. The CTX-M subtypes were determined using sequence analysis. The CTX-M-9 group was the most frequently detected ESBL group, and CTX-M-27 was the most frequently detected ESBL gene. CTX-M-15-producing strains showed significantly lower rates of susceptibility to tazobactam/piperacillin (TAZ/PIPC) than those by CTX-M-14 and -27-producing strains. Additional analysis of secondary ß-lactamases revealed that most of the OXA-1-positive strains were CTX-M-15-producing strains (94.7%). These strains displayed significantly lower susceptibility rates to TAZ/PIPC (47.4%), sulbactam/ampicillin (SBT/ABPC) (0.0%), and amikacin (AMK) (73.7%) than those by OXA-1-negative strains, suggesting that the high non-susceptibility rate of the CTX-M-15-producing strain was due to the co-carriage of OXA-1. The CTX-M-15-producing strains showed reduced susceptibility to TAZ/PIPC, SBT/ABPC, and AMK, presumably due to the co-carriage of OXA-1.

3.
Mol Metab ; 84: 101934, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38604598

RESUMEN

OBJECTIVES: During fasting, liver pivotally regulates blood glucose levels through glycogenolysis and gluconeogenesis. Kidney also produces glucose through gluconeogenesis. Gluconeogenic genes are transactivated by fasting, but their expression patterns are chronologically different between the two organs. We find that renal gluconeogenic gene expressions are positively correlated with the blood ß-hydroxybutyrate concentration. Thus, we herein aim to investigate the regulatory mechanism and its physiological implications. METHODS: Gluconeogenic gene expressions in liver and kidney were examined in hyperketogenic mice such as high-fat diet (HFD)-fed and ketogenic diet-fed mice, and in hypoketogenic PPARα knockout (PPARα-/-) mice. Renal gluconeogenesis was evaluated by rise in glycemia after glutamine loading in vivo. Functional roles of ß-hydroxybutyrate in the regulation of renal gluconeogenesis were investigated by metabolome analysis and RNA-seq analysis of proximal tubule cells. RESULTS: Renal gluconeogenic genes were transactivated concurrently with blood ß-hydroxybutyrate uprise under ketogenic states, but the increase was blunted in hypoketogenic PPARα-/- mice. Administration of 1,3-butandiol, a ketone diester, transactivated renal gluconeogenic gene expression in fasted PPARα-/- mice. In addition, HFD-fed mice showed fasting hyperglycemia along with upregulated renal gluconeogenic gene expression, which was blunted in HFD-fed PPARα-/- mice. In vitro experiments and metabolome analysis in renal tubular cells showed that ß-hydroxybutyrate directly promotes glucose and NH3 production through transactivating gluconeogenic genes. In addition, RNA-seq analysis revealed that ß-hydroxybutyrate-induced transactivation of Pck1 was mediated by C/EBPß. CONCLUSIONS: Our findings demonstrate that ß-hydroxybutyrate mediates hepato-renal interaction to maintain homeostatic regulation of blood glucose and systemic acid-base balance through renal gluconeogenesis regulation.


Asunto(s)
Gluconeogénesis , Cuerpos Cetónicos , Riñón , Hígado , Ratones Endogámicos C57BL , Ratones Noqueados , Animales , Ratones , Cuerpos Cetónicos/metabolismo , Hígado/metabolismo , Masculino , Riñón/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Dieta Alta en Grasa , PPAR alfa/metabolismo , PPAR alfa/genética , Glucemia/metabolismo , Dieta Cetogénica
4.
J Biochem ; 175(6): 649-658, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38308089

RESUMEN

α-Synuclein (α-Syn) is a protein related to synucleinopathies with high expression in the central nervous system and erythrocytes which are a major source of peripheral α-Syn. Recent reports have suggested the presence of α-Syn within extracellular vesicles (EVs) derived from erythrocytes, potentially contributing to the pathogenesis of synucleinopathies. While Lewy bodies, intracellular inclusions containing aggregated α-Syn, are prominently observed within the brain, their occurrence in peripheral neurons implies the dissemination of synucleinopathy pathology throughout the body via the propagation of α-Syn. In this study, we found erythrocytes and circulating EVs obtained from plasma contained α-Syn, which was separated into four major forms using high-resolution clear native-PAGE and isoelectric focusing. Notably, erythrocyte α-Syn was classified into full-length and C-terminal truncated forms, with truncation observed between Y133 and Q134 as determined by LC-MS/MS analysis. Our finding revealed that C-terminally truncated α-Syn, which was previously reported to exist solely within the brain, was also present in erythrocytes and circulating EVs obtained from plasma.


Asunto(s)
Eritrocitos , Procesamiento Proteico-Postraduccional , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Eritrocitos/metabolismo , Vesículas Extracelulares/metabolismo , Espectrometría de Masas en Tándem
5.
Int J Mol Sci ; 24(24)2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38139171

RESUMEN

The interaction between mRNA and ribosomal RNA (rRNA) transcription in cancer remains unclear. RNAP I and II possess a common N-terminal tail (NTT), RNA polymerase subunit RPB6, which interacts with P62 of transcription factor (TF) IIH, and is a common target for the link between mRNA and rRNA transcription. The mRNAs and rRNAs affected by FUBP1-interacting repressor (FIR) were assessed via RNA sequencing and qRT-PCR analysis. An FIR, a c-myc transcriptional repressor, and its splicing form FIRΔexon2 were examined to interact with P62. Protein interaction was investigated via isothermal titration calorimetry measurements. FIR was found to contain a highly conserved region homologous to RPB6 that interacts with P62. FIRΔexon2 competed with FIR for P62 binding and coactivated transcription of mRNAs and rRNAs. Low-molecular-weight chemical compounds that bind to FIR and FIRΔexon2 were screened for cancer treatment. A low-molecular-weight chemical, BK697, which interacts with FIRΔexon2, inhibited tumor cell growth with rRNA suppression. In this study, a novel coactivation pathway for cancer-related mRNA and rRNA transcription through TFIIH/P62 by FIRΔexon2 was proposed. Direct evidence in X-ray crystallography is required in further studies to show the conformational difference between FIR and FIRΔexon2 that affects the P62-RBP6 interaction.


Asunto(s)
Neoplasias , Proteínas Represoras , Humanos , Factores de Empalme de ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Represoras/genética , Empalme Alternativo , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Factor de Transcripción TFIIH/genética , Factor de Transcripción TFIIH/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ARN/metabolismo
7.
Commun Biol ; 6(1): 787, 2023 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-37507476

RESUMEN

Fructose-1,6-bisphosphatase (FBPase) deficiency, caused by an FBP1 mutation, is an autosomal recessive disorder characterized by hypoglycemic lactic acidosis. Due to the rarity of FBPase deficiency, the mechanism by which the mutations cause enzyme activity loss still remains unclear. Here we identify compound heterozygous missense mutations of FBP1, c.491G>A (p.G164D) and c.581T>C (p.F194S), in an adult patient with hypoglycemic lactic acidosis. The G164D and F194S FBP1 mutants exhibit decreased FBP1 protein expression and a loss of FBPase enzyme activity. The biochemical phenotypes of all previously reported FBP1 missense mutations in addition to G164D and F194S are classified into three functional categories. Type 1 mutations are located at pivotal residues in enzyme activity motifs and have no effects on protein expression. Type 2 mutations structurally cluster around the substrate binding pocket and are associated with decreased protein expression due to protein misfolding. Type 3 mutations are likely nonpathogenic. These findings demonstrate a key role of protein misfolding in mediating the pathogenesis of FBPase deficiency, particularly for Type 2 mutations. This study provides important insights that certain patients with Type 2 mutations may respond to chaperone molecules.


Asunto(s)
Acidosis Láctica , Deficiencia de Fructosa-1,6-Difosfatasa , Humanos , Deficiencia de Fructosa-1,6-Difosfatasa/genética , Deficiencia de Fructosa-1,6-Difosfatasa/complicaciones , Fructosa-Bifosfatasa/genética , Fructosa-Bifosfatasa/metabolismo , Fructosa , Acidosis Láctica/complicaciones , Acidosis Láctica/genética , Fenotipo , Genotipo , Hipoglucemiantes
8.
Sci Rep ; 13(1): 7291, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147373

RESUMEN

Glutaminase 2 (GLS2), a master regulator of glutaminolysis that is induced by p53 and converts glutamine to glutamate, is abundant in the liver but also exists in pancreatic ß-cells. However, the roles of GLS2 in islets associated with glucose metabolism are unknown, presenting a critical issue. To investigate the roles of GLS2 in pancreatic ß-cells in vivo, we generated ß-cell-specific Gls2 conditional knockout mice (Gls2 CKO), examined their glucose homeostasis, and validated the findings using a human islet single-cell analysis database. GLS2 expression markedly increased along with p53 in ß-cells from control (RIP-Cre) mice fed a high-fat diet. Furthermore, Gls2 CKO exhibited significant diabetes mellitus with gluconeogenesis and insulin resistance when fed a high-fat diet. Despite marked hyperglycaemia, impaired insulin secretion and paradoxical glucagon elevation were observed in high-fat diet-fed Gls2 CKO mice. GLS2 silencing in the pancreatic ß-cell line MIN6 revealed downregulation of insulin secretion and intracellular ATP levels, which were closely related to glucose-stimulated insulin secretion. Additionally, analysis of single-cell RNA-sequencing data from human pancreatic islet cells also revealed that GLS2 expression was elevated in ß-cells from diabetic donors compared to nondiabetic donors. Consistent with the results of Gls2 CKO, downregulated GLS2 expression in human pancreatic ß-cells from diabetic donors was associated with significantly lower insulin gene expression as well as lower expression of members of the insulin secretion pathway, including ATPase and several molecules that signal to insulin secretory granules, in ß-cells but higher glucagon gene expression in α-cells. Although the exact mechanism by which ß-cell-specific GLS2 regulates insulin and glucagon requires further study, our data indicate that GLS2 in pancreatic ß-cells maintains glucose homeostasis under the condition of hyperglycaemia.


Asunto(s)
Hiperglucemia , Células Secretoras de Insulina , Islotes Pancreáticos , Ratones , Humanos , Animales , Hiperglucemia/metabolismo , Glucagón/metabolismo , Glutaminasa/genética , Glutaminasa/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Insulina/metabolismo , Glucosa/metabolismo , Ratones Noqueados , Homeostasis
9.
Sci Rep ; 13(1): 5731, 2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-37029177

RESUMEN

Although polymerase chain reaction (PCR) amplification and sequencing of the bacterial 16S rDNA region has numerous scientific applications, it does not provide DNA methylation information. Herein, we propose a simple extension for bisulfite sequencing to investigate 5-methylcytosine residues in the bacterial 16S rDNA region from clinical isolates or flora. Multiple displacement amplification without DNA denaturation was used to preferentially pre-amplify single-stranded bacterial DNA after bisulfite conversion. Following the pre-amplification, the 16S rDNA region was analyzed using nested bisulfite PCR and sequencing, enabling the simultaneous identification of DNA methylation status and sequence data. We used this approach (termed sm16S rDNA PCR/sequencing) to identify novel methylation sites and a methyltransferase (M. MmnI) in Morganella morganii and different methylation motifs among Enterococcus faecalis strains from small volumes of clinical specimens. Further, our analysis suggested that M. MmnI may be correlated to erythromycin resistance. Thus, sm16S rDNA PCR/sequencing is a useful extension method for analyzing the DNA methylation of 16S rDNA regions in a microflora, providing additional information not provided by conventional PCR. Given the relationship between DNA methylation status and drug resistance in bacteria, we believe this technique can be effectively applied in clinical sample testing.


Asunto(s)
Bacterias , Metilación de ADN , ADN Ribosómico/genética , ADN Ribosómico/análisis , ADN Bacteriano/química , Bacterias/genética , Análisis de Secuencia de ADN , ARN Ribosómico 16S/genética
10.
J Biochem ; 173(3): 177-184, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36469357

RESUMEN

α-Synuclein is a protein linked to various synuclein-associated diseases ('synucleinopathies'), including Parkinson's disease, dementia with Lewy Bodies and multiple system atrophy, and is highly expressed in the central nervous system and in erythrocytes. Moreover, α-synuclein-containing erythrocyte-derived extracellular vesicles may be involved in the pathogenesis of synucleinopathies and their progression across the blood-brain barrier. Several post-translational modifications of α-synuclein have been reported in brain inclusions, including S129 phosphorylation, but fewer have been found in erythrocytes. In this study, we analysed the post-translational modifications of erythrocyte α-synuclein using liquid chromatography-mass spectrometry. We found that all lysine residues in the α-synuclein protein could be modified by acetylation, glycation, ubiquitination or SUMOylation but that phosphorylation, nitration and acylation were uncommon minor post-translational modifications in erythrocytes. Since the post-translational modification of lysine residues has been implicated in both membrane association and protein clearance, our findings provide new insight into how synucleinopathies may progress and suggest possible therapeutic strategies designed to target α-synuclein.


Asunto(s)
Lisina , alfa-Sinucleína , Eritrocitos , Fosforilación , Procesamiento Proteico-Postraduccional , Humanos
11.
Sci Rep ; 12(1): 18443, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36323841

RESUMEN

The microRNA (miR) miR-874, a potential tumour suppressor, causes cell death via target gene suppression in various cancer types. Mevalonate pathway inhibition also causes cell death in breast cancer. However, the relationship between the mevalonate pathway and miR-874-induced apoptosis or its association with the tumour suppressor p53 has not been elucidated. We identified phosphomevalonate kinase (PMVK), a key mevalonate pathway enzyme, and sterol regulatory element-binding factor 2 (SREBF2), the master cholesterol biosynthesis regulator, as direct miR­874 targets. Next-generation sequencing analysis revealed a significant miR-874-mediated downregulation of PMVK and SREBF2 gene expression and p53 pathway enrichment. Luciferase reporter assays showed that miR-874 directly regulated PMVK and SREBF2. miR-874-induced apoptosis was p53 dependent, and single-cell RNA sequencing analysis demonstrated that miR-874 transfection resulted in apoptosis and p53 pathway activation. Downregulation of PMVK expression also caused cell cycle arrest and p53 pathway activation, which was rescued by geranylgeranyl pyrophosphate (GGPP) supplementation. Analysis of The Cancer Genome Atlas (TCGA) database indicated a negative correlation between miR-874 and PMVK expression and between miR-874 and SREBF2 expression. These findings suggest that miR-874 suppresses the mevalonate pathway by targeting SREBF2 and PMVK, resulting in GGPP depletion, which activates the p53 pathway and promotes cycle arrest or apoptosis.


Asunto(s)
MicroARNs , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ácido Mevalónico/metabolismo , Línea Celular Tumoral , MicroARNs/metabolismo , Apoptosis/genética , Transformación Celular Neoplásica/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica
12.
Commun Biol ; 5(1): 1304, 2022 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-36435867

RESUMEN

The clinical characteristics of growth hormone (GH)-producing pituitary adenomas/somatotroph pituitary neuroendocrine tumors (GHomas/somatotroph PitNETs) vary across patients. In this study, we aimed to integrate the genetic alterations, protein expression profiles, transcriptomes, and clinical characteristics of GHomas/somatotroph PitNETs to identify molecules associated with acromegaly characteristics. Targeted capture sequencing and copy number analysis of 36 genes and nontargeted proteomics analysis were performed on fresh-frozen samples from 121 sporadic GHomas/somatotroph PitNETs. Targeted capture sequencing revealed GNAS as the only driver gene, as previously reported. Classification by consensus clustering using both RNA sequencing and proteomics revealed many similarities between the proteome and the transcriptome. Gene ontology analysis was performed for differentially expressed proteins between wild-type and mutant GNAS samples identified by nontargeted proteomics and involved in G protein-coupled receptor (GPCR) pathways. The results suggested that GNAS mutations impact endocrinological features in acromegaly through GPCR pathway induction. ATP2A2 and ARID5B correlated with the GH change rate in the octreotide loading test, and WWC3, SERINC1, and ZFAND3 correlated with the tumor volume change rate after somatostatin analog treatment. These results identified a biological connection between GNAS mutations and the clinical and biochemical characteristics of acromegaly, revealing molecules associated with acromegaly that may affect medical treatment efficacy.


Asunto(s)
Acromegalia , Adenoma , Adenoma Hipofisario Secretor de Hormona del Crecimiento , Tumores Neuroendocrinos , Neoplasias Hipofisarias , Proteogenómica , Somatotrofos , Humanos , Somatotrofos/metabolismo , Somatotrofos/patología , Acromegalia/complicaciones , Acromegalia/metabolismo , Acromegalia/patología , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Tumores Neuroendocrinos/genética , Tumores Neuroendocrinos/patología , Adenoma/genética , Adenoma/metabolismo , Adenoma/patología , Adenoma Hipofisario Secretor de Hormona del Crecimiento/genética , Adenoma Hipofisario Secretor de Hormona del Crecimiento/complicaciones , Adenoma Hipofisario Secretor de Hormona del Crecimiento/patología
13.
J Med Invest ; 69(3.4): 287-293, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36244782

RESUMEN

Objective : To examine diagnostic performance of corticotropin-releasing hormone (CRH) test combined with baseline dehydroepiandrosterone sulfate (DHEA-S) in patients with a suspect of central adrenal insufficiency. Methods : Patients (n=215) requiring daily or intermittent hydrocortisone replacement, or no replacement were retrospectively checked with their peak cortisol after CRH test and baseline DHEA-S. Results :  None of 106 patients with the peak cortisol ≥ 17.5 µg / dL after CRH test required replacement, and all 64 patients with the peak cortisol < 10.0 µg / dL required daily replacement. Among 8 patients with 10.0 µg / dL ≤ the peak cortisol < 17.5 µg / dL and baseline DHEA-S below the reference range, 6 patients required daily replacement and 1 patient was under intermittent replacement. Among 37 patients with 10.0 µg / dL ≤ the peak cortisol < 17.5 µg / dL and baseline DHEA-S within the reference range, 10 and 6 patients were under intermittent and daily replacement, respectively. Conclusions : No patients with the peak cortisol ≥ 17.5 µg / dL required hydrocortisone replacement, and all patients with the peak cortisol below 10.0 µg / dL required daily replacement. Careful clinical evaluation was required to determine requirement for replacement in patients with 10.0 µg / dL ≤ the peak cortisol < 17.5 µg / dL even in combination with baseline DHEA-S. J. Med. Invest. 69 : 287-293, August, 2022.


Asunto(s)
Insuficiencia Suprarrenal , Hidrocortisona , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/tratamiento farmacológico , Hormona Adrenocorticotrópica , Algoritmos , Hormona Liberadora de Corticotropina , Sulfato de Deshidroepiandrosterona , Humanos , Estudios Retrospectivos
14.
Nat Commun ; 13(1): 5408, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109558

RESUMEN

The liver stores glycogen and releases glucose into the blood upon increased energy demand. Group 2 innate lymphoid cells (ILC2) in adipose and pancreatic tissues are known for their involvement in glucose homeostasis, but the metabolic contribution of liver ILC2s has not been studied in detail. Here we show that liver ILC2s are directly involved in the regulation of blood glucose levels. Mechanistically, interleukin (IL)-33 treatment induces IL-13 production in liver ILC2s, while directly suppressing gluconeogenesis in a specific Hnf4a/G6pc-high primary hepatocyte cluster via Stat3. These hepatocytes significantly interact with liver ILC2s via IL-13/IL-13 receptor signaling. The results of transcriptional complex analysis and GATA3-ChIP-seq, ATAC-seq, and scRNA-seq trajectory analyses establish a positive regulatory role for the transcription factor GATA3 in IL-13 production by liver ILC2s, while AP-1 family members are shown to suppress IL-13 release. Thus, we identify a regulatory role and molecular mechanism by which liver ILC2s contribute to glucose homeostasis.


Asunto(s)
Gluconeogénesis , Interleucina-13 , Glucemia/metabolismo , Factor de Transcripción GATA3/genética , Factor de Transcripción GATA3/metabolismo , Glucógeno/metabolismo , Inmunidad Innata , Interleucina-13/metabolismo , Hígado/metabolismo , Linfocitos/metabolismo , Receptores de Interleucina-13/metabolismo , Factor de Transcripción AP-1/metabolismo
15.
J Biol Chem ; 298(11): 102506, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36126774

RESUMEN

Hematopoietic stem and progenitor cells can differentiate into all types of blood cells. Regulatory mechanisms underlying pluripotency in progenitors, such as the ability of lymphoid progenitor cells to differentiate into T-lineage, remain unclear. We have previously reported that LIM domain only 2 (Lmo2), a bridging factor in large transcriptional complexes, is essential to retain the ability of lymphoid progenitors to differentiate into T-lineage. However, biochemical characterization of Lmo2 protein complexes in physiological hematopoietic progenitors remains obscure. Here, we identified approximately 600 Lmo2-interacting molecules in a lymphoid progenitor cell line by two-step affinity purification with LC-MS/MS analysis. Zinc finger and BTB domain containing 1 (Zbtb1) and CBFA2/RUNX1 partner transcriptional corepressor 3 (Cbfa2t3) were found to be the functionally important binding partners of Lmo2. We determined CRISPR/Cas9-mediated acute disruption of Zbtb1 or Cbfa2t3 in the lymphoid progenitor or bone marrow-derived primary hematopoietic progenitor cells causes significant defects in the initiation of T-cell development when Notch signaling is activated. Our transcriptome analysis of Zbtb1- or Cbfa2t3-deficient lymphoid progenitors revealed that Tcf7 was a common target for both factors. Additionally, ChIP-seq analysis showed that Lmo2, Zbtb1, and Cbfa2t3 cobind to the Tcf7 upstream enhancer region, which is occupied by the Notch intracellular domain/RBPJ transcriptional complex after Notch stimulation, in lymphoid progenitors. Moreover, transduction with Tcf7 restored the defect in the T-lineage potential of Zbtb1-deficient lymphoid progenitors. Thus, in lymphoid progenitors, the Lmo2/Zbtb1/Cbfa2t3 complex directly binds to the Tcf7 locus and maintains responsiveness to the Notch-mediated inductive signaling to facilitate T-lineage differentiation.


Asunto(s)
Células Progenitoras Linfoides , Factores de Transcripción , Células Progenitoras Linfoides/fisiología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , Células Madre Hematopoyéticas/metabolismo , Diferenciación Celular , Proteínas con Dominio LIM/genética , Proteínas con Dominio LIM/metabolismo
16.
Cancer Res ; 82(18): 3209-3222, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-35895807

RESUMEN

Glutamine synthase 2 (GLS2) is a key regulator of glutaminolysis and has been previously implicated in activities consistent with tumor suppression. Here we generated Gls2 knockout (KO) mice that develop late-occurring B-cell lymphomas and hepatocellular carcinomas (HCC). Further, Gls2 KO mice subjected to the hepatocarcinogenic Stelic Animal Model (STAM) protocol produce larger HCC tumors than seen in wild-type (WT) mice. GLS2 has been shown to promote ferroptosis, a form of cell death characterized by iron-dependent accumulation of lipid peroxides. In line with this, GLS2 deficiency, either in cells derived from Gls2 KO mice or in human cancer cells depleted of GLS2, conferred significant resistance to ferroptosis. Mechanistically, GLS2, but not GLS1, increased lipid reactive oxygen species (ROS) production by facilitating the conversion of glutamate to α-ketoglutarate (αKG), thereby promoting ferroptosis. Ectopic expression of WT GLS2 in a human hepatic adenocarcinoma xenograft model significantly reduced tumor size; this effect was nullified by either expressing a catalytically inactive form of GLS2 or by blocking ferroptosis. Furthermore, analysis of cancer patient datasets supported a role for GLS2-mediated regulation of ferroptosis in human tumor suppression. These data suggest that GLS2 is a bona fide tumor suppressor and that its ability to favor ferroptosis by regulating glutaminolysis contributes to its tumor suppressive function. SIGNIFICANCE: This study demonstrates that the key regulator of glutaminolysis, GLS2, can limit HCC in vivo by promoting ferroptosis through αKG-dependent lipid ROS, which in turn might lay the foundation for a novel therapeutic approach.


Asunto(s)
Carcinoma Hepatocelular , Ferroptosis , Glutaminasa/metabolismo , Neoplasias Hepáticas , Animales , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Ferroptosis/genética , Glutamatos , Glutaminasa/genética , Glutamina/metabolismo , Humanos , Hierro , Ácidos Cetoglutáricos , Peróxidos Lipídicos , Neoplasias Hepáticas/patología , Ratones , Especies Reactivas de Oxígeno
17.
J Clin Endocrinol Metab ; 107(9): 2545-2555, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35730597

RESUMEN

CONTEXT: Pheochromocytoma and paraganglioma (PPGL) may appear as a complication of cyanotic congenital heart disease (CCHD-PPGL) with frequent EPAS1 mutations, suggesting a close link between EPAS1 mutations and tissue hypoxia in CCHD-PPGL pathogenesis. OBJECTIVE: Our aim is to further investigate the role of EPAS1 mutations in the hypoxia-driven mechanism of CCHD-PPGL pathogenesis, particularly focusing on metachronous and/or multifocal CCHD-PPGL tumors. METHODS: We performed whole-exome sequencing (WES) for somatic and germline mutations in 15 PPGL samples from 7 CCHD patients, including 3 patients with metachronous and/or multifocal tumors, together with an adrenal medullary hyperplasia (AMH) sample. RESULTS: We detected EPAS1 mutations in 15 out of 16 PPGL/AMH samples from 7 cases. Conspicuously, all EPAS1 mutations in each of 3 cases with multifocal or metachronous tumors were mutually independent and typical examples of parallel evolution, which is suggestive of strong positive selection of EPAS1-mutated clones. Compared to 165 The Cancer Genome Atlas non-CCHD-PPGL samples, CCHD-PPGL/AMH samples were enriched for 11p deletions (13/16) and 2p amplifications (4/16). Of particular note, the multiple metachronous PPGL tumors with additional copy number abnormalities developed 18 to 23 years after the resolution of hypoxemia, suggesting that CCHD-induced hypoxic environments are critical for positive selection of EPAS1 mutants in early life, but may no longer be required for development of PPGL in later life. CONCLUSION: Our results highlight a key role of activated hypoxia-inducible factor 2α due to mutated EPAS1 in positive selection under hypoxic environments, although hypoxemia itself may not necessarily be required for the EPAS1-mutated clones to progress to PPGL.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Cardiopatías Congénitas , Paraganglioma , Feocromocitoma , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasias de las Glándulas Suprarrenales/genética , Neoplasias de las Glándulas Suprarrenales/patología , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/genética , Humanos , Hipoxia/genética , Paraganglioma/complicaciones , Paraganglioma/genética , Paraganglioma/patología , Feocromocitoma/complicaciones , Feocromocitoma/genética , Feocromocitoma/patología
18.
Parkinsons Dis ; 2022: 8649195, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35386951

RESUMEN

Taq1A polymorphism is a DRD2 gene variant located in an exon of the ANKK1 gene and has an important role in the brain's dopaminergic functions. Some studies have indicated that A1 carriers have an increased risk of developing Parkinson's disease (PD) and show poorer clinical performance than A2 homo carriers. Previous studies have suggested that A1 carriers had fewer dopamine D2 receptors in the caudate and increased cortical activity as a compensatory mechanism. However, there is little information about morphological changes associated with this polymorphism in patients with PD. The study's aim was to investigate the relationship between brain volume and Taq1A polymorphism in PD using voxel-based morphometry (VBM). Based on Taq1A polymorphism, 103 patients with PD were divided into two groups: A1 carriers (A1/A1 and A1/A2) and A2 homo carriers (A2/A2). The volume of the left prefrontal cortex (PFC) was significantly decreased in A2 homo carriers compared to A1 carriers. This finding supports the association between Taq1A polymorphism and brain volume in PD and may explain the compensation of cortical function in A1 carriers with PD.

19.
Endocr J ; 69(4): 327-359, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35418526

RESUMEN

Primary aldosteronism (PA) is associated with higher cardiovascular morbidity and mortality rates than essential hypertension. The Japan Endocrine Society (JES) has developed an updated guideline for PA, based on the evidence, especially from Japan. We should preferentially screen hypertensive patients with a high prevalence of PA with aldosterone to renin ratio ≥200 and plasma aldosterone concentrations (PAC) ≥60 pg/mL as a cut-off of positive results. While we should confirm excess aldosterone secretion by one positive confirmatory test, we could bypass patients with typical PA findings. Since PAC became lower due to a change in assay methods from radioimmunoassay to chemiluminescent enzyme immunoassay, borderline ranges were set for screening and confirmatory tests and provisionally designated as positive. We recommend individualized medicine for those in the borderline range for the next step. We recommend evaluating cortisol co-secretion in patients with adrenal macroadenomas. Although we recommend adrenal venous sampling for lateralization before adrenalectomy, we should carefully select patients rather than all patients, and we suggest bypassing in young patients with typical PA findings. A selectivity index ≥5 and a lateralization index >4 after adrenocorticotropic hormone stimulation defines successful catheterization and unilateral subtype diagnosis. We recommend adrenalectomy for unilateral PA and mineralocorticoid receptor antagonists for bilateral PA. Systematic as well as individualized clinical practice is always warranted. This JES guideline 2021 provides updated rational evidence and recommendations for the clinical practice of PA, leading to improved quality of the clinical practice of hypertension.


Asunto(s)
Hiperaldosteronismo , Hipertensión , Adrenalectomía , Aldosterona , Humanos , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/terapia , Hipertensión/complicaciones , Japón , Antagonistas de Receptores de Mineralocorticoides , Renina
20.
Leukemia ; 36(2): 452-463, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34497325

RESUMEN

Insufficiency of polycomb repressive complex 2 (PRC2), which trimethylates histone H3 at lysine 27, is frequently found in primary myelofibrosis and promotes the development of JAK2V617F-induced myelofibrosis in mice by enhancing the production of dysplastic megakaryocytes. Polycomb group ring finger protein 1 (Pcgf1) is a component of PRC1.1, a non-canonical PRC1 that monoubiquitylates H2A at lysine 119 (H2AK119ub1). We herein investigated the impact of PRC1.1 insufficiency on myelofibrosis. The deletion of Pcgf1 in JAK2V617F mice strongly promoted the development of lethal myelofibrosis accompanied by a block in erythroid differentiation. Transcriptome and chromatin immunoprecipitation sequence analyses showed the de-repression of PRC1.1 target genes in Pcgf1-deficient JAK2V617F hematopoietic progenitors and revealed Hoxa cluster genes as direct targets. The deletion of Pcgf1 in JAK2V617F hematopoietic stem and progenitor cells (HSPCs), as well as the overexpression of Hoxa9, restored the attenuated proliferation of JAK2V617F progenitors. The overexpression of Hoxa9 also enhanced JAK2V617F-mediated myelofibrosis. The expression of PRC2 target genes identified in PRC2-insufficient JAK2V617F HSPCs was not largely altered in Pcgf1-deleted JAK2V617F HSPCs. The present results revealed a tumor suppressor function for PRC1.1 in myelofibrosis and suggest that PRC1.1 insufficiency has a different impact from that of PRC2 insufficiency on the pathogenesis of myelofibrosis.


Asunto(s)
Diferenciación Celular , Janus Quinasa 2/genética , Mutación , Complejo Represivo Polycomb 1/fisiología , Mielofibrosis Primaria/patología , Animales , Femenino , Lisina , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mielofibrosis Primaria/etiología , Mielofibrosis Primaria/metabolismo , Ubiquitinación
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