Identification of genomic regions and pathways associated with traits related to rumen acidosis in feedlot Nellore cattle.

There may be an increased risk of metabolic disorders, such as rumen acidosis, in cattle fed high-concentrate diets, particularly those from Bos taurus indicus genotypes, which have shown to be more sensitive to ruminal acidification. Therefore, this study aimed to estimate (co)variance components and identify genomic regions and pathways associated with ruminal acidosis in feedlot Nellore cattle fed high-concentrate diets. It was utilized a dataset containing a total of 642 Nellore bulls that were genotyped from seven feedlot nutrition studies. The GGP Indicus 35k panel was used with the single step genome-wide association study methodology in which the effects of the markers were obtained from the genomic values estimated by the GBLUP model. A bivariate model to estimate genetic correlations between the economically important traits and indicator traits for acidosis was used. The traits evaluated in this study that were nutritionally related to rumen acidosis included average daily gain (ADG), final body weight, time spent eating (TSE), time spent ruminating, rumenitis score (RUM), rumen absorptive surface area (ASA), rumen keratinized layer thickness (KER) and hot carcass weight (HCW). The identified candidate genes were mainly involved in the negative or non-regulation of the apoptotic process, salivary secretion, and transmembrane transport. The genetic correlation between HCW and ASA was low positive (0.27 ± 0.23), and between ADG and ASA was high moderate (0.58 ± 0.59). A positive genetic correlation between RUM and all performance traits was observed, and TSE correlated negatively with HCW (-0.33 ± 0.21), ASA (-0.75 ± 0.48), and KER (-0.40 ± 0.27). The genetic association between economically important traits and indicator traits for acidosis suggested that Nellore cattle may be more sensitive to acidosis in feedlot systems.

Transcriptomic Response to Acidosis Reveals Its Contribution to Bone Metastasis in Breast Cancer Cells.

Bone is the most common site of metastasis in breast cancer. Metastasis is promoted by acidosis, which is associated with osteoporosis. To investigate how acidosis could promote bone metastasis, we compared differentially expressed genes (DEGs) in MDA-MB-231 cancer cells in acidosis, bone metastasis, and bone metastatic tumors. The DEGs were identified using Biojupies and GEO2R. The expression profiles were assessed with Morpheus. The overlapping DEGs between acidosis and bone metastasis were compared to the bulk of the DEGs in terms of the most important genes and enriched terms using CytoHubba and STRING. The expression of the genes in this overlap filtered by secreted proteins was assessed in the osteoporosis secretome. The analysis revealed that acidosis-associated transcriptomic changes were more similar to bone metastasis than bone metastatic tumors. Extracellular matrix (ECM) organization would be the main biological process shared between acidosis and bone metastasis. The secretome genes upregulated in acidosis, bone metastasis, and osteoporosis-associated mesenchymal stem cells are enriched for ECM organization and angiogenesis. Therefore, acidosis may be more important in the metastatic niche than in the primary tumor. Acidosis may contribute to bone metastasis by promoting ECM organization. Untreated osteoporosis could favor bone metastasis through the increased secretion of ECM organization proteins.

Transcriptional analysis of hnRNPA0, A1, A2, B1, and A3 in lung cancer cell lines in response to acidosis, hypoxia, and serum deprivation conditions.

The ribonucleoproteins (hnRNPs) have important roles in multiple aspects of nucleic acid metabolism and in the regulation of different cellular processes. Abnormal expression of hnRNPs has been reported in several types of cancer including lung, pancreatic, and gastric carcinomas. Heterogenous tumor cell populations generate a tumor microenvironment that can present normoxic, hypoxic, or acidic regions. The analysis of hnRNP transcriptional responses considering the changing nature of the tumor microenvironment is important to understand tumor cell survival under stress conditions. We analyzed the transcriptional response of hnRNPA0, A1, A2, B1, and A3 in lung tumor cell lines under acidosis, hypoxia, and serum deprivation conditions. We used qRT-PCR to obtain a relative quantification of the hnRNPA/B transcript levels. We found that the hnRNPA2 transcript was the most abundant, followed by B1, A0, and A1. Expression of hnRNPA3 was the lowest, although its transcript levels were the most constant. hnRNPA/B transcript levels in lung tumor cell lines responded to changes in the microenvironment; however, hnRNPB1 transcript levels relative to hnRNPA2 expression did no change in all tested stress conditions, indicating that the alternative splicing between these isoforms was constant. hnRNPA1, A2, and B1 transcript levels were upregulated under serum deprivation conditions; possibly to promote a migration phenotype. Our data provide new insights into the transcriptional responses of ribonucleoproteins that might favor tumor cell survival and migration.

Distinct mechanisms underlie adaptation of proximal tubule Na+/H+ exchanger isoform 3 in response to chronic metabolic and respiratory acidosis.

The Na(+/)H(+) exchanger isoform 3 (NHE3) is essential for HCO(3)(-) reabsorption in renal proximal tubules. The expression and function of NHE3 must adapt to acid-base conditions. The goal of this study was to elucidate the mechanisms responsible for higher proton secretion in proximal tubules during acidosis and to evaluate whether there are differences between metabolic and respiratory acidosis with regard to NHE3 modulation and, if so, to identify the relevant parameters that may trigger these distinct adaptive responses. We achieved metabolic acidosis by lowering HCO(3)(-) concentration in the cell culture medium and respiratory acidosis by increasing CO(2) tension in the incubator chamber. We found that cell-surface NHE3 expression was increased in response to both forms of acidosis. Mild (pH 7.21 ± 0.02) and severe (6.95 ± 0.07) metabolic acidosis increased mRNA levels, at least in part due to up-regulation of transcription, whilst mild (7.11 ± 0.03) and severe (6.86 ± 0.01) respiratory acidosis did not up-regulate NHE3 expression. Analyses of the Nhe3 promoter region suggested that the regulatory elements sensitive to metabolic acidosis are located between -466 and -153 bp, where two consensus binding sites for SP1, a transcription factor up-regulated in metabolic acidosis, were localised. We conclude that metabolic acidosis induces Nhe3 promoter activation, which results in higher mRNA and total protein level. At the plasma membrane surface, NHE3 expression was increased in metabolic and respiratory acidosis alike, suggesting that low pH is responsible for NHE3 displacement to the cell surface.

Neonatal presentation of Gordon syndrome.

Gordon syndrome, the association of hypertension with hyperkalemic acidosis, has been described in older children and adults. We report an affected family in which two of the members had exhibited the metabolic manifestations of the disease since infancy. Both patients responded well to thiazides. To our knowledge, these are the youngest patients with documented cases of Gordon syndrome.

[Phenotypic expression variation of isovaleric acidemia in Argentinian patients. A long term follow-up]. / Variación en la expresión fenotípica de la acidemia isovalérica en pacientes argentinos. Observaciones de un prolongado seguimiento.

In this paper we discuss the first five Argentinean patients presenting isovaleric acidemia (IVA), an alteration of leucine catabolism due to a genetic defect of isovaleryl-CoA dehydrogenase. Belonging to unrelated families, one from native (H. Fam.) and the other from Italian ancestry (M. Fam.); the patients presented the clinical pattern highly suggestive of the disease: they were siblings, had disease-free intervals, vomiting, ketoacidosis crises, "sweaty feet" odor and progression of the neurologic involvement from somnolence and stupor to profound coma. In the four children of H. Fam. the disease had a late but severe beginning; one of the girls died (N.H.). The boy from M. Fam. presented a neonatal form of clearly benign course. The disease was confirmed by gas-chromatography (GC) of volatile acids in serum and also by the typical urinary acid GC-profiles (Fig. 1, A and B); the isovalerylglycine quantitative evaluation in urinary samples collected during crises is shown in Table 1. The morphological findings in liver and brain of N.H. showed at the ultrastructural study, an extensive fatty degeneration and greatly marked mitochondrial alterations in the liver and edema, neuronal karyorrhexis and karyolysis in the brain (Fig. 2). The therapeutic protocol based on a low leucine or low protein diet and use of glycine is described. The evolutionary follow up, more than 10 years for the first case, showed a normal mental development in three of them and retardation in the first child of H. Fam., who had a late diagnosis. IVA is still valuable as a paradigm in the acquisition of a highly clinical suspicion and for its introduction in the study of genetic organic acidemias.

Variacion en la expresion fenotipica de la acidemia isovalerica en pacientes argentinos: observaciones de un prolongado seguimiento / Phenotypic expression variation of isovaleric acidemia in Argentinian patients: a long term follow-up

La acidemia isovalérica (AIV) es una enfermedad genética causada por una deficiencia de la isovaleril-CoA dehidrogenasa, enzima involucrada en un paso catabólico de la leucina. El cuadro clínico se caracteriza por crisis cetoacidóticas, progresivo compromiso neurológico y olor a "sudor de pies". En este trabajo se presentan los primeros cinco pacientes argentinos pertenecientes a dos familias no emparentadas. En una de ellas, los cuatro hijos afectados manifestaron una severa forma crónica intermitente con muerte de uno de los enfermos (N.H.). En el niño de la segunda familia, la AIV se expresó como una forma neonatal de curso inusualmente benigno. El diagnóstico definitivo se realizó con el análisis de los ácidos orgánicos por cromatografía gaseosa la cual confirmó el masivo incremento sérico del ácido isovalérico durante las crisis y la presencia permanente de la isovaleriglicina en las orinas de crisis y en las de remisión. La ultraestructura del hígado y cerebro de H.H. señlaron para el primero metamorfosis grasa y marcados cambios en las mitocondrias; en el cerebro, las células neuronales y gliales evidencian acentuada tumefacción, alteraciones en sus organoides, cariorrexis. El largo seguimiento clínico, alrededor de diez años para el primer paciente, permitió observar por un lado, una disminución, alteraciones en sus organoides, cariolisis y cariorrexis. El largo seguimiento clínico, alrededor de diez años para el primer paciente, permitió observar por un lado, una disminución gradual de la frecuencia y severidad de las crisis con el desarrollo y tendencia a desaparecer entre los 6 y 7 años de edad; por otra parte fue posible calificar como efecto diferenciado sobre la vida e intelecto de los enfermos, la precocidad del tratamiento de la emergencia metabólica y del dietético pero también dependiente del fenotipo que la heterogeneidad marcó para cada uno de ellos. La experiencia genéticas y para adquirir una alta sospecha clínica frente a estas inéditas patologías en nuestro medio

Variacion en la expresion fenotipica de la acidemia isovalerica en pacientes argentinos: observaciones de un prolongado seguimiento / Phenotypic expression variation of isovaleric acidemia in Argentinian patients: a long term follow-up

La acidemia isovalérica (AIV) es una enfermedad genética causada por una deficiencia de la isovaleril-CoA dehidrogenasa, enzima involucrada en un paso catabólico de la leucina. El cuadro clínico se caracteriza por crisis cetoacidóticas, progresivo compromiso neurológico y olor a "sudor de pies". En este trabajo se presentan los primeros cinco pacientes argentinos pertenecientes a dos familias no emparentadas. En una de ellas, los cuatro hijos afectados manifestaron una severa forma crónica intermitente con muerte de uno de los enfermos (N.H.). En el niño de la segunda familia, la AIV se expresó como una forma neonatal de curso inusualmente benigno. El diagnóstico definitivo se realizó con el análisis de los ácidos orgánicos por cromatografía gaseosa la cual confirmó el masivo incremento sérico del ácido isovalérico durante las crisis y la presencia permanente de la isovaleriglicina en las orinas de crisis y en las de remisión. La ultraestructura del hígado y cerebro de H.H. señlaron para el primero metamorfosis grasa y marcados cambios en las mitocondrias; en el cerebro, las células neuronales y gliales evidencian acentuada tumefacción, alteraciones en sus organoides, cariorrexis. El largo seguimiento clínico, alrededor de diez años para el primer paciente, permitió observar por un lado, una disminución, alteraciones en sus organoides, cariolisis y cariorrexis. El largo seguimiento clínico, alrededor de diez años para el primer paciente, permitió observar por un lado, una disminución gradual de la frecuencia y severidad de las crisis con el desarrollo y tendencia a desaparecer entre los 6 y 7 años de edad; por otra parte fue posible calificar como efecto diferenciado sobre la vida e intelecto de los enfermos, la precocidad del tratamiento de la emergencia metabólica y del dietético pero también dependiente del fenotipo que la heterogeneidad marcó para cada uno de ellos. La experiencia genéticas y para adquirir una alta sospecha clínica frente a estas inéditas patologías en nuestro medio (AU)

Lactic acidosis in biotin-responsive multiple carboxylase deficiency caused by holocarboxylase synthetase deficiency of early and late onset.

Two patients with biotin-responsive multiple carboxylase deficiency, both presenting with predominant lactic acidosis, are reported. One with disease of early neonatal onset had considerable acute neurologic and persistent dermatologic abnormalities. The other, with late juvenile-onset disease, had chronic neurologic abnormalities without dermatologic findings. Early-onset cases generally have been associated with holocarboxylase synthetase deficiency, whereas those of juvenile onset have been characterized as representing defects in intestinal biotin absorption. However, enzyme analyses of fibroblasts from both patients, grown in biotin-deficient medium, revealed markedly diminished activities of pyruvate, propionyl-CoA, and beta-methylcrotonyl-CoA carboxylases, and all three enzymes showed normal activities after growth in biotin-rich medium. Furthermore, lymphoblast enzyme analysis in the patient with disease of early onset had previously revealed a defect in holocarboxylase synthetase, and fibroblast complementation studies showed that both patients belong to the bio complementation group. These findings indicate that considerable clinical heterogeneity exists among patients with holocarboxylase synthetase deficiency, an observation which does not permit differentiation of the biochemical forms of multiple carboxylase deficiency on the basis of age at onset and clinical presentation.

Cerebro-hepato-renal syndrome of Zellweger. A report of eight cases with comments upon the incidence, the liver lesion, and a fault in pipecolic acid metabolism.

Studies of eight patients with this syndrome confirm the characteristic pattern of abnormalities and the autosomal recessive mode of inheritance. The incidence is estimated to be approximately 1 in 100,000 live births. The liver lesion proved to be variable, with features of progressive parenchymal damage rather than a developmental defect of small bile ducts as previously suggested. Elevated levels of pipecolic acid were found in blood and urine and may be related to the basic defect.