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1.
Breast Cancer Res Treat ; 177(3): 767-770, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31292799

RESUMEN

PURPOSE: Between 5 and 10% of cases of breast cancer (BC) are attributable to a genetic susceptibility. The BRCA1 and BRCA2 genes described in the late 1990s are associated with an increased risk of breast and ovarian cancer, and the clinical management of carriers of pathogenic variants in these genes is defined in several clinical guidelines (Paluch-Shimon et al. in Ann Oncol 27(suppl 5):v103-v110, 2016; Llort et al. in Clin Transl Oncol 17(12):956-961, 2015). However, the pathogenic variants in BRCA1 and BRCA2 represent only a third of the causes of hereditary BC (Easton et al. in N Engl J Med 372:2243-2257, 2015). The incorporation of NGS (Next Generation Sequencing) techniques in the genetic diagnosis of this pathology, in addition to minimising the cost and time of analysis, allows the simultaneous study of other genes of high and moderate penetrance (Easton et al. in N Engl J Med 372:2243-2257, 2015; Op. Cit.; Tung et al. in Cancer 121(1):25-33, 2015). To date, there are not many cases or series of patients that describe the co-occurrence of two pathogenic variants in these genes of BC. Cases of double heterozygosis have been described with the presence of pathogenic variants in BRCA1, BRCA2, PALB2, CHEK2, BLM or NBN (Nomizu et al. in Breast Cancer 22(5):557-61, 2015; Heidemann et al. in Breast Cancer Res Treat 134(3):1229-1239, 2012; Zuradelli et al. in Breast Cancer Res Treat 124(1):251-258, 2010; Sokolenko et al. in Breast Cancer Res Treat 145(2):553-562, 2014). METHODS: We report the case of a patient diagnosed with multiple tumours who presented two pathogenic variants in heterozygosis. RESULTS: Two pathogenic variants, c.5123C > A (p.Ala1708Glu) in the BRCA1 gene and c.2413C > T (p.Arg805X) in the ATM gene were detected in heterozygosis. Said variants were confirmed by Sanger-type sequencing using specific primers. CONCLUSIONS: The implementation of gene panels using NGS in the study of hereditary cancer involves the detection of heterozygous double mutations in genes of high and moderate penetrance for cancer, although with a low frequency.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteína BRCA1/genética , Heterocigoto , Mutación , Neoplasias Primarias Secundarias/diagnóstico , Neoplasias Primarias Secundarias/etiología , Alelos , Análisis Mutacional de ADN , Femenino , Genotipo , Humanos , Masculino , Linaje
2.
Part Fibre Toxicol ; 14(1): 41, 2017 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-29073907

RESUMEN

BACKGROUND: The special physicochemical properties of gold nanoprisms make them very useful for biomedical applications including biosensing and cancer therapy. However, it is not clear how gold nanoprisms may affect cellular physiology including viability and other critical functions. We report a multiparametric investigation on the impact of gold-nanoprisms on mice and human, transformed and primary cells as well as tissue distribution and toxicity in vivo after parental injection. METHODS: Cellular uptake of the gold-nanoprisms (NPRs) and the most crucial parameters of cell fitness such as generation of reactive oxygen species (ROS), mitochondria membrane potential, cell morphology and apoptosis were systematically assayed in cells. Organ distribution and toxicity including inflammatory response were analysed in vivo in mice at 3 days or 4 months after parental administration. RESULTS: Internalized gold-nanoprisms have a significant impact in cell morphology, mitochondrial function and ROS production, which however do not affect the potential of cells to proliferate and form colonies. In vivo NPRs were only detected in spleen and liver at 3 days and 4 months after administration, which correlated with some changes in tissue architecture. However, the main serum biochemical markers of organ damage and inflammation (TNFα and IFNγ) remained unaltered even after 4 months. In addition, animals did not show any macroscopic sign of toxicity and remained healthy during all the study period. CONCLUSION: Our data indicate that these gold-nanoprisms are neither cytotoxic nor cytostatic in transformed and primary cells, and suggest that extensive parameters should be analysed in different cell types to draw useful conclusions on nanomaterials safety. Moreover, although there is a tendency for the NPRs to accumulate in liver and spleen, there is no observable negative impact on animal health.


Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Oro/toxicidad , Nanopartículas del Metal/toxicidad , Células A549 , Animales , Línea Celular Transformada , Forma de la Célula/efectos de los fármacos , Femenino , Oro/administración & dosificación , Oro/farmacocinética , Células HeLa , Humanos , Mediadores de Inflamación/sangre , Inyecciones Intravenosas , Interferón gamma/sangre , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Nanopartículas del Metal/administración & dosificación , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Cultivo Primario de Células , Especies Reactivas de Oxígeno/metabolismo , Medición de Riesgo , Distribución Tisular , Factor de Necrosis Tumoral alfa/sangre
3.
An Sist Sanit Navar ; 46(2)2023 Aug 16.
Artículo en Español | MEDLINE | ID: mdl-37594060

RESUMEN

BACKGROUND: Our study aims to evaluate the impact of different factors on cancer-related cognitive impairment in patients who undergo chemotherapy. METHODOLOGY: Prospective longitudinal single-centre study that included patients with breast and colon carcinoma who underwent chemotherapy as part of their treatment. Clinical and genetic characteristics of the patients (single nucleotide polymorphisms, SNPs) were collected. Patients' neurocognitive status was assessed using eleven validated tests at three time points: before chemotherapy (M0 - baseline), between one and four weeks after completing chemotherapy (M1), and between 24-30 weeks after completing chemotherapy (M2). RESULTS: Sixty-two patients were included in this study; 82% were female, median age was 56 years (range 30-74), and 64.5% had been diagnosed with breast cancer. Overall, better cognitive results at M0 were associated with age < 55 years, higher educational level, absence of comorbidities, and the CC variant rs471692 (TOP2A). Significant decline was found between M0 to M1 in the Rey Auditory Verbal Learning Test and the Letter and Number test, with evidence of recovery in M2 compared to M0 regarding the following test: Visual Memory, Functioning Assessment Short Test (FAST), Digit Symbol Substitution and Cube. In the multivariate analysis, being =55 years of age, adjuvant chemotherapy, presence of comorbidities, tobacco and alcohol use, and GT variant rs1800795 were associated with cognitive decline between M0 and M1. CONCLUSION: Being =55 years of age, female, presence of comorbidities and basic education level are related to a higher risk of cognitive impairment after chemotherapy.


Asunto(s)
Neoplasias de la Mama , Disfunción Cognitiva , Neoplasias Colorrectales , Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Masculino , Estudios Prospectivos , Factores de Riesgo , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/tratamiento farmacológico , Disfunción Cognitiva/inducido químicamente , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/tratamiento farmacológico
4.
Front Genet ; 14: 1274108, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38476463

RESUMEN

Inherited mutations in the CHEK2 gene have been associated with an increased lifetime risk of developing breast cancer (BC). We aim to identify in the study population the prevalence of mutations in the CHEK2 gene in diagnosed BC patients, evaluate the phenotypic characteristics of the tumor and family history, and predict the deleteriousness of the variants of uncertain significance (VUS). A genetic study was performed, from May 2016 to April 2020, in 396 patients diagnosed with BC at the University Hospital Lozano Blesa of Zaragoza, Spain. Patients with a genetic variant in the CHEK2 gene were selected for the study. We performed a descriptive analysis of the clinical variables, a bibliographic review of the variants, and a cosegregation study when possible. Moreover, an in-depth bioinformatics analysis of CHEK2 VUS was carried out. We identified nine genetic variants in the CHEK2 gene in 10 patients (two pathogenic variants and seven VUS). This supposes a prevalence of 0.75% and 1.77%, respectively. In all cases, there was a family history of BC in first- and/or second-degree relatives. We carried out a cosegregation study in two families, being positive in one of them. The bioinformatics analyses predicted the pathogenicity of six of the VUS. In conclusion, CHEK2 mutations have been associated with an increased risk for BC. This risk is well-established for foundation variants. However, the risk assessment for other variants is unclear. The incorporation of bioinformatics analysis provided supporting evidence of the pathogenicity of VUS.

5.
J Lipid Res ; 53(10): 2046-2056, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22847177

RESUMEN

A novel lyase activity enzyme is characterized for the first time: HMG-CoA lyase-like1 (er-cHL), which is a close homolog of mitochondrial HMG-CoA lyase (mHL). Initial data show that there are nine mature transcripts for the novel gene HMGCLL1, although none of them has all its exons. The most abundant transcript is called "variant b," and it lacks exons 2 and 3. Moreover, a three-dimensional model of the novel enzyme is proposed. Colocalization studies show a dual location of the er-cHL in the endoplasmic reticulum (ER) and cytosol, but not in mitochondria or peroxisomes. Furthermore, the dissociation experiment suggests that it is a nonendoplasmic reticulum integral membrane protein. The kinetic parameters of er-cHL indicate that it has a lower V(max) and a higher substrate affinity than mHL. Protein expression and lyase activity were found in several tissues, and were particularly strong in lung and kidney. The occurrence of er-cHL in brain is surprising, as mHL has not been found there. Although mHL activity is clearly associated with energy metabolism, the results suggest that er-cHL is more closely related to another metabolic function, mostly at the pulmonary and brain level.


Asunto(s)
Citosol/enzimología , Retículo Endoplásmico/enzimología , Oxo-Ácido-Liasas/análisis , Oxo-Ácido-Liasas/química , Secuencia de Aminoácidos , Citosol/metabolismo , Retículo Endoplásmico/metabolismo , Células HEK293 , Humanos , Mitocondrias/enzimología , Mitocondrias/metabolismo , Datos de Secuencia Molecular , Oxo-Ácido-Liasas/genética , Peroxisomas/enzimología , Peroxisomas/metabolismo , Empalme de Proteína
6.
Mol Biol Rep ; 39(4): 4777-85, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21952825

RESUMEN

The genes HMGCS2 and HMGCL encode the two main enzymes for ketone-body synthesis, mitochondrial HMG-CoA synthase and HMG-CoA lyase. Here, we identify and describe possible splice variants of these genes in human tissues. We detected an alternative transcript of HMGCS2 carrying a deletion of exon 4, and two alternative transcripts of HMGCL with deletions of exons 5 and 6, and exons 5, 6 and 7, respectively. All splice variants maintained the reading frame. However, Western blot studies and overexpression measurements in eukaryotic or prokaryotic cell models did not reveal HL or mHS protein variants. Both genes showed a similar distribution of the inactive variants in different tissues. Surprisingly, the highest percentages were found in tissues where almost no ketone bodies are synthesized: heart, skeletal muscle and brain. Our results suggest that alternative splicing might coordinately block the two main enzymes of ketogenesis in specific human tissues.


Asunto(s)
Empalme Alternativo/genética , Vías Biosintéticas/genética , Hidroximetilglutaril-CoA Sintasa/genética , Cuerpos Cetónicos/biosíntesis , Mitocondrias/enzimología , Mitocondrias/genética , Oxo-Ácido-Liasas/genética , Western Blotting , Biología Computacional , Células HEK293 , Humanos , Hidroximetilglutaril-CoA Sintasa/química , Hidroximetilglutaril-CoA Sintasa/metabolismo , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Oxo-Ácido-Liasas/química , Oxo-Ácido-Liasas/metabolismo , Estructura Secundaria de Proteína , Reacción en Cadena en Tiempo Real de la Polimerasa
7.
Int J Cardiol ; 301: 220-225, 2020 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-31740141

RESUMEN

Transthyretin amyloidosis can be either the wild-type (ATTR-wt) or the hereditary form (ATTR-m) with autosomal dominant inheritance. ATTR seems to be an underdiagnosed disease, despite now being recognized as one of the most frequent causes of heart failure (HF) with preserved ejection fraction. The confirmation of diagnosis includes a genetic analysis as a critical step to distinguish between ATTR-wt and hereditary amyloidosis. The present study aimed to evaluate the potential application of High-Resolution Melting (HRM) analysis for identifying gene mutations in patients with suspected ATTR-m. We have adapted and validated the use of HRM for TTR mutations. We, therefore, sequenced the TTR gene and used HRM in a group of 134 patients suspected of suffering from amyloidosis. Seven patients were diagnosed with mutations in the TTR gene (p.Glu74Gln, heterozygous p.Val142Ile, and homozygous p.Val142Ile). HRM is capable of clearly detecting these TTR mutations, including the heterozygous and homozygous variants. The results show a 100% correlation between the HRM study and TTR sequencing. These results support future studies of applying HRM analysis as a diagnostic approach for ATTR-m, mainly for epidemiological studies.


Asunto(s)
Neuropatías Amiloides Familiares , Cardiomiopatías , Errores Diagnósticos/prevención & control , Pruebas Genéticas/métodos , Insuficiencia Cardíaca , Prealbúmina/genética , Neuropatías Amiloides Familiares/diagnóstico , Neuropatías Amiloides Familiares/epidemiología , Neuropatías Amiloides Familiares/genética , Cardiomiopatías/etiología , Cardiomiopatías/fisiopatología , Diagnóstico Diferencial , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/patología , Humanos , Mutación , España/epidemiología , Volumen Sistólico
8.
Mult Scler Relat Disord ; 38: 101466, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31715500

RESUMEN

BACKGROUND: The presence of white mater lesions in the central nervous system forces the differential diagnosis between multiple sclerosis (MS) and Anderson-Fabry disease (FD). Due to the type of inheritance, linked to the X chromosome, the diagnosis of FD is especially difficult in women. Tissue´s deposits of globotriaosylceramide (Gb3) are characteristics for FD and the deacylated form of Gb3 (Globotriaosylsphingosine or LysoGb3) is specific for this entity. Our objective is to investigate if concentrations of plasma Lyso-Gb3 are useful for ruling out the FD in a Spanish cohort of patients with a previous diagnosis of MS. METHODS: we evaluated the α-galactosidase A enzymatic activity in 154 patients with a previous diagnosis of MS (93 women and 61 men): 103 Relapsing Remitting MS patients, 19 progressive MS patients and 32 with the clinically isolated syndrome. 116 (75% of the patients) were on MS disease modifying therapy. Enzymatic assay was completed in all cases and done on dried blood spot (DBS) samples. Subsequently the GLA gene was sequenced only in males and females who presented an enzymatic assay significantly lower than standardized controls (<50% for men and <75% for women). For subjects with GLA variants, plasma Lyso-Gb3 levels were performed by Tandem mass spectrometry from DBS, assuming a cut-off point for normality <3.5 ng/mL. RESULTS: Genetic study was carried out in 30 women and 7 men; 8 of them had non-previous described GLA variants. After a thorough clinical examination no organic disease was found in any of the classical target organs. The study of Lyso-Gb3 concentrations in DBS was lower than 3.5 ng/mL, allowing us to discharge FD in all subjects and to consider these GLA variants like non pathologic. CONCLUSIONS: Lyso-Gb3 concentration in DBS is a useful tool to rule out Fabry disease in patients with MS. A concentration of LysoGb3 < 3.5 ng/mL rules out FD.


Asunto(s)
Enfermedad de Fabry/sangre , Enfermedad de Fabry/diagnóstico , Glucolípidos/sangre , Esclerosis Múltiple/sangre , Esclerosis Múltiple/diagnóstico , Esfingolípidos/sangre , Anciano , Biomarcadores/sangre , Diagnóstico Diferencial , Pruebas con Sangre Seca , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
9.
Hum Mutat ; 30(3): E520-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19177531

RESUMEN

3-Hydroxy-3-methylglutaric aciduria is a rare autosomal recessive genetic disorder that affects ketogenesis and L-leucine catabolism. The clinical acute symptoms include vomiting, convulsions, metabolic acidosis, hypoketotic hypoglycaemia and lethargy. To date, 33 mutations in 100 patients have been reported in the HMGCL gene. In this study 10 new mutations in 24 patients are described. They include: 5 missense mutations: c.109G>A, c.425C>T, c.521G>A, c.575T>C and c.598A>T, 2 nonsense mutations: c.242G>A and c.559G>T, one small deletion: c.853delC, and 2 mutations in intron regions: c.497+4A>G and c.750+1G>A. Two prevalent mutations were detected, 109G>T (E37X) in 38% of disease alleles analyzed and c.504_505delCT in 10% of them. Although patients are mainly of European origin (71%) and mostly Spanish (54%), the group is ethnically diverse and includes, for the first time, patients from Pakistan, Palestine and Ecuador. We also present a simple, efficient method to express the enzyme and we analyze the possible functional effects of missense mutations. The finding that all identified missense mutations cause a >95% decrease in the enzyme activity, indicates that the disease appears only in very severe genotypes."


Asunto(s)
Meglutol/metabolismo , Errores Innatos del Metabolismo/genética , Mutación , Oxo-Ácido-Liasas/genética , Alelos , Secuencia de Aminoácidos , Árabes/genética , Dominio Catalítico/genética , Análisis Mutacional de ADN , Ecuador , Europa (Continente) , Frecuencia de los Genes , Genotipo , Humanos , Cinética , Errores Innatos del Metabolismo/etnología , Errores Innatos del Metabolismo/patología , Modelos Moleculares , Datos de Secuencia Molecular , Mutación Missense , Oxo-Ácido-Liasas/química , Oxo-Ácido-Liasas/metabolismo , Pakistán , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido
10.
Front Public Health ; 7: 289, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31649914

RESUMEN

Objective: Pneumocystis colonization is frequent in patients with chronic obstructive pulmonary disease (COPD) producing local and systemic inflammation. Heart failure is also a common comorbidity among patients with COPD. Heart failure is a chronic, frequent, and disabling condition with high morbidity and mortality, but with a modifiable course where endothelial dysfunction and pulmonary arterial hypertension have great importance. Animal models have shown that Pneumocystis infection can cause relevant functionally changes in vascular responses in the lung, promoting the development of pulmonary hypertension. Pneumocystis colonization could be a hidden cause of worsening heart failure through it capacity to induce inflammatory response with subsequent endothelial dysfunction and pulmonary hypertension. The aim of the present study was to investigate the prevalence of Pneumocystis jirovecii colonization in heart failure patients and its possible association with reduced or preserved ejection fraction. Methods: A cross-sectional study was carried out including 36 heart failure patients and 36 control cases. Identification of P. jirovecii colonization was performed by means of molecular techniques in oropharyngeal washing. Results: Pneumocystis-DNA was identified in oropharyngeal washing in 1 (2.7%) of 36 heart failure patients and in 3 (8.3%) of 36 controls. Conclusions: Pneumocystis colonization does not seem to have a role in the pathophysiology of heart failure.

11.
An. sist. sanit. Navar ; 46(2): [e1040], May-Agos. 2023. tab, ilus
Artículo en Español | IBECS (España) | ID: ibc-224229

RESUMEN

Fundamento: Nuestro estudio se plantea con el objetivo deevaluar el impacto de diferentes factores individuales sobre eldeterioro cognitivo relacionado con el cáncer en pacientes tratados con quimioterapia. Material y métodos: Estudio unicéntrico longitudinal prospectivo. Incluyó pacientes con carcinoma de mama y colon tratados con quimioterapia. Se recogieron variables clínicas y genéticas del paciente (polimorfismos de nucleótido simple, SNP). Los pacientes fueron evaluados neurocognitivamente con oncetest validados, en tres momentos: basal previo a quimioterapia(M0), entre una y cuatro semanas tras finalizar quimioterapia(M1) y entre 24-30 semanas tras finalizar quimioterapia (M2). Resultados: Se incluyeron 62 pacientes, 82% mujeres, con mediana de edad de 56 años (rango 30-74), un 64,5% con cáncer demama. La edad <55 años, tener estudios superiores, ausenciade comorbilidades y presencia de la variante CC de rs471692(TOP2A) se asociaron, en general, con mejores resultados cognitivos en M0. Se observó un empeoramiento significativo deM0 a M1 en los test RAVLT y Letras y números, y recuperaciónen M2 respecto a M0 en los test de memoria visual, FAST, clavede números, y cubos. La edad ≥55 años, la quimioterapia adyuvante, las comorbilidades, el consumo de tabaco y de alcoholy la variante GT de rs1800795 se relacionaron con el deterioroentre M0 y M1 en el modelo multivariante. Conclusiones: La edad mayor de 55 años, el sexo femenino, lapresencia de comorbilidades y el nivel básico de estudios serelacionan con un mayor riesgo de deterioro cognitivo tras eltratamiento con quimioterapia.(AU)


Background: Our study aims to evaluate the impact of differentfactors on cancer-related cognitive impairment in patients whoundergo chemotherapy.Methodology: Prospective longitudinal single-centre studythat included patients with breast and colon carcinoma whounderwent chemotherapy as part of their treatment. Clinicaland genetic characteristics of the patients (single nucleotidepolymorphisms, SNPs) were collected. Patients’ neurocognitivestatus was assessed using eleven validated tests at three timepoints: before chemotherapy (M0 - baseline), between one andfour weeks after completing chemotherapy (M1), and between24-30 weeks after completing chemotherapy (M2).Results: Sixty-two patients were included in this study; 82% werefemale, median age was 56 years (range 30-74), and 64.5% had beendiagnosed with breast cancer. Overall, better cognitive results atM0 were associated with age < 55 years, higher educational level,absence of comorbidities, and the CC variant rs471692 (TOP2A).Significant decline was found between M0 to M1 in the Rey Auditory Verbal Learning Test and the Letter and Number test, with evidence of recovery in M2 compared to M0 regarding the followingtest: Visual Memory, Functioning Assessment Short Test (FAST),Digit Symbol Substitution and Cube. In the multivariate analysis,being ≥55 years of age, adjuvant chemotherapy, presence of comorbidities, tobacco and alcohol use, and GT variant rs1800795were associated with cognitive decline between M0 and M1.Conclusion: Being ≥55 years of age, female, presence of comorbidities and basic education level are related to a higher risk ofcognitive impairment after chemotherapy.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Disfunción Cognitiva , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias del Colon/tratamiento farmacológico , Quimioterapia , Polimorfismo Genético , Neoplasias/terapia , Neoplasias/tratamiento farmacológico , Factores de Riesgo , Estudios Longitudinales , Estudios Prospectivos
12.
Biophys Chem ; 115(2-3): 241-5, 2005 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15752612

RESUMEN

HMG-CoA lyase (HL) deficiency is a rare autosomal recessive genetic disorder that affects ketogenesis and leucine catabolism. We report a new Spanish patient who bears the frequent nonsense mutation G109T (Mediterranean mutation). This mutation can produce aberrant splicing with three mRNA variants: one of the expected size, the second with deletion of exon 2, and the third with deletion of exons 2 and 3. Recently our group proposed a 3D model for human HL containing a (beta-alpha)(8) (TIM) barrel structure. We have studied the effect of the deletions of exon 2 and exons 2 plus 3 on the proposed HL model. Exon 2 skipping led to the loss of beta-sheet 1, and the skipping of exons 2 and 3 caused the disappearance of alpha helix 1 and beta-sheets 1 and 2.-


Asunto(s)
Exones/genética , Modelos Moleculares , Oxo-Ácido-Liasas/química , Oxo-Ácido-Liasas/metabolismo , Secuencia de Bases , Sitios de Unión , Codón sin Sentido/genética , Humanos , Lactante , Masculino , Oxo-Ácido-Liasas/genética , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , España
13.
Cell Rep ; 8(2): 420-9, 2014 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-25017060

RESUMEN

During bacterial sepsis, proinflammatory cytokines contribute to multiorgan failure and death in a process regulated in part by cytolytic cell granzymes. When challenged with a sublethal dose of the identified mouse pathogen Brucella microti, wild-type (WT) and granzyme A (gzmA)(-/-) mice eliminate the organism from liver and spleen in 2 or 3 weeks, whereas the bacteria persist in mice lacking perforin or granzyme B as well as in mice depleted of Tc cells. In comparison, after a fatal challenge, only gzmA(-/-) mice exhibit increased survival, which correlated with reduced proinflammatory cytokines. Depletion of natural killer (NK) cells protects WT mice from sepsis without influencing bacterial clearance and the transfer of WT, but not gzmA(-/-) NK, cells into gzmA(-/-) recipients restores the susceptibility to sepsis. Therefore, infection-related pathology, but not bacterial clearance, appears to require gzmA, suggesting the protease may be a therapeutic target for the prevention of bacterial sepsis without affecting immune control of the pathogen.


Asunto(s)
Bacteriemia/metabolismo , Granzimas/metabolismo , Animales , Brucella , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Granzimas/genética , Células Asesinas Naturales/metabolismo , Hígado/metabolismo , Hígado/patología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Bazo/metabolismo , Bazo/patología
14.
Eur J Med Genet ; 56(8): 411-5, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23751782

RESUMEN

Mitochondrial HMG-CoA synthase deficiency is a rare inherited metabolic disorder that affects ketone-body synthesis. Acute episodes include vomiting, lethargy, hepatomegaly, hypoglycaemia, dicarboxylic aciduria, and in severe cases, coma. This deficiency may have been under-diagnosed owing to the absence of specific clinical and biochemical markers, limitations in liver biopsy and the lack of an effective method of expression and enzyme assay for verifying the mutations found. To date, eight patients have been reported with nine allelic variants of the HMGCS2 gene. We present a new method of enzyme expression and a modification of the activity assay that allows, for first time, the functional study of missense mutations found in patients with this deficiency. Four of the missense mutations (p.V54M, p.R188H, p.G212R and p.G388R) did not produce proteins that could have been detected in soluble form by western blot; three produced a total loss of activity (p.Y167C, p.M307T and p.R500H) and one, variant p.F174L, gave an enzyme with a catalytic efficiency of 11.5%. This indicates that the deficiency may occur with partial loss of activity of enzyme. In addition, we describe a new patient with this deficiency, in which we detected the missense allelic variant, c.1162G>A (p.G388R) and the nonsense variant c.1270C>T (p.R424X).


Asunto(s)
Hidroximetilglutaril-CoA Sintasa/deficiencia , Hidroximetilglutaril-CoA Sintasa/genética , Hidroximetilglutaril-CoA Sintasa/metabolismo , Hipoglucemia/enzimología , Hipoglucemia/genética , Errores Innatos del Metabolismo/enzimología , Errores Innatos del Metabolismo/genética , Enfermedades Mitocondriales/enzimología , Enfermedades Mitocondriales/genética , Mutación , Secuencia de Aminoácidos , Secuencia de Bases , Análisis Mutacional de ADN , Activación Enzimática , Exones , Orden Génico , Humanos , Hidroximetilglutaril-CoA Sintasa/química , Lactante , Masculino , Modelos Moleculares , Mutación Missense , Conformación Proteica
15.
Mol Genet Metab ; 92(3): 198-209, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17692550

RESUMEN

3-Hydroxy-3-methylglutaryl-CoA lyase (HL) deficiency is a rare autosomal recessive genetic disorder that affects ketogenesis and l-leucine catabolism, which generally appears during the first year of life. Patients with HL deficiency have a reduced capacity to synthesize ketone bodies. The disease is caused by lethal mutations in the HL gene (HMGCL). To date, up to 30 variant alleles (28 mutations and 2 SNPs) in 93 patients have been reported, with a recognizable population-specific mutational spectrum. This disorder is frequent in Saudi Arabia and the Iberian Peninsula (Portugal and Spain), where two mutations (122G>A and 109G>A) have been identified in 87% and 94% of the cases, respectively. In most countries a few patients have a high level of allelic heterogeneity. The mutations are distributed along the gene sequences, although some clustering was observed in exon 2, conforming a possible hot spot. Recently, the crystal structures of the human and two bacterial HL have been published. These experimentally obtained structures confirmed the overall architecture, previously predicted by our group and others using bioinformatic approaches, which shows the (betaalpha)8-barrel structure of the enzyme. In addition, the crystals confirmed the presence of an additional COOH domain containing important structures and residues for enzyme functionality and oligomerization processes. Here, we review all HMGCL mis-sense mutations identified to date, and their implication in enzyme structure and function is discussed. We found that genotype-phenotype correlations are difficult to establish because the evolution of the disease seems more related to the causes of hypoglycaemia (fasting or acute illness) than to a particular genotype.


Asunto(s)
Mutación , Oxo-Ácido-Liasas/deficiencia , Oxo-Ácido-Liasas/genética , Errores Innatos del Metabolismo de los Aminoácidos , Secuencia de Aminoácidos , Humanos , Biología Molecular , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
16.
Mol Genet Metab ; 91(2): 120-7, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17459752

RESUMEN

3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) lyase adopts a (betaalpha)(8) TIM barrel structure with an additional beta9, alpha11 and alpha12 helices. Location of HMG part of the substrate has been suggested but the binding mode for the CoA moiety remains to be resolved. As mutation F305 fs(-2), which involves the last 21 residues of the protein, and mutation K48N caused 3-hydroxy-3-methylglutaric aciduria in two patients, we examined the role of the C-terminal end and Lys(48) in enzyme activity. Expression studies of various C-terminal-end-deleted and K48N-mutated proteins revealed that residues 311-313 (localized in the loop between alpha11 and alpha12 helices) and Lys(48) are essential for enzyme activity. An in silico docking model locating HMG-CoA on the surface of the enzyme implicates Asn(311) and Lys(313) in substrate binding by establishing multiple polar contacts with phosphate and ribose groups of adenosine, and Lys(48) by contacting the carboxyl group of the panthotenic acid moiety.


Asunto(s)
Acilcoenzima A/química , Oxo-Ácido-Liasas/química , Oxo-Ácido-Liasas/genética , Secuencia de Aminoácidos , Secuencia Conservada , Escherichia coli/metabolismo , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Oxo-Ácido-Liasas/biosíntesis , Oxo-Ácido-Liasas/deficiencia , Unión Proteica , Estructura Secundaria de Proteína , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
17.
J Biol Chem ; 278(31): 29016-23, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12746442

RESUMEN

This study describes three novel homozygous missense mutations (S75R, S201Y, and D204N) in the 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) lyase gene, which caused 3-hydroxy-3-methylglutaric aciduria in patients from Germany, England, and Argentina. Expression studies in Escherichia coli show that S75R and S201Y substitutions completely abolished the HMG-CoA lyase activity, whereas D204N reduced catalytic efficiency to 6.6% of the wild type. We also propose a three-dimensional model for human HMG-CoA lyase containing a (betaalpha)8 (TIM) barrel structure. The model is supported by the similarity with analogous TIM barrel structures of functionally related proteins, by the localization of catalytic amino acids at the active site, and by the coincidence between the shape of the substrate (HMG-CoA) and the predicted inner cavity. The three novel mutations explain the lack of HMG-CoA lyase activity on the basis of the proposed structure: in S75R and S201Y because the new amino acid residues occlude the substrate cavity, and in D204N because the mutation alters the electrochemical environment of the active site. We also report the localization of all missense mutations reported to date and show that these mutations are located in the beta-sheets around the substrate cavity.


Asunto(s)
Modelos Moleculares , Mutación Missense , Oxo-Ácido-Liasas/química , Oxo-Ácido-Liasas/deficiencia , Secuencia de Aminoácidos , Animales , Sitios de Unión , Escherichia coli/genética , Femenino , Expresión Génica , Homocigoto , Humanos , Lactante , Recién Nacido , Masculino , Meglutol/orina , Datos de Secuencia Molecular , Estructura Molecular , Mutagénesis Sitio-Dirigida , Oxo-Ácido-Liasas/genética , Pliegue de Proteína , Estructura Secundaria de Proteína , Proteínas Recombinantes , Alineación de Secuencia
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