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We have generated using CRISPR/Cas9 technology a partially humanized mouse model of the neurometabolic disease phenylketonuria (PKU), carrying the highly prevalent PAH variant c.1066-11G>A. This variant creates an alternative 3' splice site, leading to the inclusion of 9 nucleotides coding for 3 extra amino acids between Q355 and Y356 of the protein. Homozygous Pah c.1066-11A mice, with a partially humanized intron 10 sequence with the variant, accurately recapitulate the splicing defect and present almost undetectable hepatic PAH activity. They exhibit fur hypopigmentation, lower brain and body weight and reduced survival. Blood and brain phenylalanine levels are elevated, along with decreased tyrosine, tryptophan and monoamine neurotransmitter levels. They present behavioral deficits, mainly hypoactivity and diminished social interaction, locomotor deficiencies and an abnormal hind-limb clasping reflex. Changes in the morphology of glial cells, increased GFAP and Iba1 staining signals and decreased myelinization are observed. Hepatic tissue exhibits nearly absent PAH protein, reduced levels of chaperones DNAJC12 and HSP70 and increased autophagy markers LAMP1 and LC3BII, suggesting possible coaggregation of mutant PAH with chaperones and subsequent autophagy processing. This PKU mouse model with a prevalent human variant represents a useful tool for pathophysiology research and for novel therapies development.
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Modelos Animais de Doenças , Fenilalanina Hidroxilase , Fenilcetonúrias , Animais , Camundongos , Fenilcetonúrias/genética , Fenilcetonúrias/patologia , Fenilcetonúrias/metabolismo , Humanos , Fenilalanina Hidroxilase/genética , Fenilalanina Hidroxilase/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Sistemas CRISPR-Cas , Autofagia/genética , Mutação , Fígado/metabolismo , Fígado/patologiaRESUMO
A wide range of approaches can be used to detect micro RNA (miRNA)-target gene pairs (mTPs) from expression data, differing in the ways the gene and miRNA expression profiles are calculated, combined and correlated. However, there is no clear consensus on which is the best approach across all datasets. Here, we have implemented multiple strategies and applied them to three distinct rare disease datasets that comprise smallRNA-Seq and RNA-Seq data obtained from the same samples, obtaining mTPs related to the disease pathology. All datasets were preprocessed using a standardized, freely available computational workflow, DEG_workflow. This workflow includes coRmiT, a method to compare multiple strategies for mTP detection. We used it to investigate the overlap of the detected mTPs with predicted and validated mTPs from 11 different databases. Results show that there is no clear best strategy for mTP detection applicable to all situations. We therefore propose the integration of the results of the different strategies by selecting the one with the highest odds ratio for each miRNA, as the optimal way to integrate the results. We applied this selection-integration method to the datasets and showed it to be robust to changes in the predicted and validated mTP databases. Our findings have important implications for miRNA analysis. coRmiT is implemented as part of the ExpHunterSuite Bioconductor package available from https://bioconductor.org/packages/ExpHunterSuite.
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MicroRNAs , Consenso , Bases de Dados Factuais , MicroRNAs/genética , Razão de Chances , RNA-SeqRESUMO
Phenylketonuria (PKU) is a genetic disorder caused by variations in the phenylalanine hydroxylase (PAH) gene. Among the 3369 reported PAH variants, 33.7% are missense alterations. Unfortunately, 30% of these missense variants are classified as variants of unknown significance (VUS), posing challenges for genetic risk assessment. In our study, we focused on analyzing 836 missense PAH variants following the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) guidelines specified by ClinGen PAH Variant Curation Expert Panel (VCEP) criteria. We utilized and compared variant annotator tools like Franklin and Varsome, conducted 3D structural analysis of PAH, and examined active and regulatory site hotspots. In addition, we assessed potential splicing effect of apparent missense variants. By evaluating phenotype data from 22962 PKU patients, our aim was to reassess the pathogenicity of missense variants. Our comprehensive approach successfully reclassified 309 VUSs out of 836 missense variants as likely pathogenic or pathogenic (37%), upgraded 370 likely pathogenic variants to pathogenic, and reclassified one previously considered likely benign variant as likely pathogenic. Phenotypic information was available for 636 missense variants, with 441 undergoing 3D structural analysis and active site hotspot identification for 180 variants. After our analysis, only 6% of missense variants were classified as VUSs, and three of them (c.23A>C/p.Asn8Thr, c.59_60delinsCC/p.Gln20Pro, and c.278A >T/p.Asn93Ile) may be influenced by abnormal splicing. Moreover, a pathogenic variant (c.168G>T/p.Glu56Asp) was identified to have a risk exceeding 98% for modifications of the consensus splice site, with high scores indicating a donor loss of 0.94. The integration of ACMG/AMP guidelines with in silico structural analysis and phenotypic data significantly reduced the number of missense VUSs, providing a strong basis for genetic counseling and emphasizing the importance of metabolic phenotype information in variant curation. This study also sheds light on the current landscape of PAH variants.
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Mutação de Sentido Incorreto , Fenótipo , Fenilalanina Hidroxilase , Fenilcetonúrias , Humanos , Fenilalanina Hidroxilase/genética , Fenilalanina Hidroxilase/química , Fenilcetonúrias/genética , Fenilcetonúrias/patologia , Simulação por ComputadorRESUMO
Phosphomannomutase 2 deficiency (PMM2-CDG), the most frequent congenital disorder of glycosylation, is an autosomal recessive disease caused by biallelic pathogenic variants in the PMM2 gene. There is no cure for this multisystemic syndrome. Some of the therapeutic approaches that are currently in development include mannose-1-phosphate replacement therapy, drug repurposing, and the use of small chemical molecules to correct folding defects. Preclinical models are needed to evaluate the efficacy of treatments to overcome the high lethality of the available animal model. In addition, the number of variants with unknown significance is increasing in clinical settings. This study presents the generation of a cellular disease model by knocking out the PMM2 gene in the hepatoma HepG2 cell line using CRISPR-Cas9 gene editing. The HepG2 knockout model accurately replicates the PMM2-CDG phenotype, exhibiting a complete absence of PMM2 protein and mRNA, a 90% decrease in PMM enzymatic activity, and altered ICAM-1, LAMP1 and A1AT glycoprotein patterns. The evaluation of PMM2 disease-causing variants validates the model's utility for studying new PMM2 clinical variants, providing insights for diagnosis and potentially for evaluating therapies. A CRISPR-Cas9-generated HepG2 knockout model accurately recapitulates the PMM2-CDG phenotype, providing a valuable tool for assessing disease-causing variants and advancing therapeutic strategies.
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INTRODUCTION: Existing research highlights the significance of prosocial behavior (voluntary, intentional behavior that results in benefits for another) to people's well-being. Yet, the extent to which this expected positive relation operates at the within-person level (e.g., is more prosocial behavior than usual related to a higher than usual level of well-being?) while taking into account stable interindividual differences, remains a research question that deserves further investigation. In this study, we aimed to explore the relations between prosocial behavior and hedonic (HWB; subjective assessment of life satisfaction and happiness) and eudaimonic (EWB; actualization of human potential in alignment with personal goals, including concepts like meaning in life and closeness to others) well-being in daily life. METHOD: Using ecological momentary assessment for 4 weeks, data were collected from two British samples, comprising 82 adolescents and 166 adults. RESULTS: Dynamic Structural Equation Modeling revealed a positive relations between prosocial behavior and HWB/EWB at both between and within-person levels across the samples. CONCLUSION: In summary, these findings further support the positive link between prosocial behavior and well-being in everyday life. Notably, this association was consistent across different age groups (adolescent and adults) at both between and within-person levels.
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The pathophysiology of nonketotic hyperglycinemia (NKH), a rare neuro-metabolic disorder associated with severe brain malformations and life-threatening neurological manifestations, remains incompletely understood. Therefore, a valid human neural model is essential. We aimed to investigate the impact of GLDC gene variants, which cause NKH, on cellular fitness during the differentiation process of human induced pluripotent stem cells (iPSCs) into iPSC-derived astrocytes and to identify sustainable mechanisms capable of overcoming GLDC deficiency. We developed the GLDC27-FiPS4F-1 line and performed metabolomic, mRNA abundance, and protein analyses. This study showed that although GLDC27-FiPS4F-1 maintained the parental genetic profile, it underwent a metabolic switch to an altered serine-glycine-one-carbon metabolism with a coordinated cell growth and cell cycle proliferation response. We then differentiated the iPSCs into neural progenitor cells (NPCs) and astrocyte-lineage cells. Our analysis showed that GLDC-deficient NPCs had shifted towards a more heterogeneous astrocyte lineage with increased expression of the radial glial markers GFAP and GLAST and the neuronal markers MAP2 and NeuN. In addition, we detected changes in other genes related to serine and glycine metabolism and transport, all consistent with the need to maintain glycine at physiological levels. These findings improve our understanding of the pathology of nonketotic hyperglycinemia and offer new perspectives for therapeutic options.
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Hiperglicinemia não Cetótica , Células-Tronco Pluripotentes Induzidas , Humanos , Hiperglicinemia não Cetótica/genética , Hiperglicinemia não Cetótica/patologia , Glicina Desidrogenase (Descarboxilante)/genética , Astrócitos/patologia , Células-Tronco Pluripotentes Induzidas/patologia , Glicina , SerinaRESUMO
Hypertension is the most prevalent modifiable risk factor for stroke and is associated with worse functional outcomes. Pharmacological inhibition of histone deacetylases by suberoylanilide hydroxamic acid (SAHA) modulates gene expression and has emerged as a promising therapeutic approach to reduce ischaemic brain injury. Here, we have tested the therapeutic potential of SAHA administered during reperfusion in adult male spontaneously hypertensive (SHR) rats subjected to transient middle cerebral artery occlusion (tMCAO; 90â¯min occlusion/24â¯h reperfusion). Animals received a single dose of SAHA (50â¯mg/kg) or vehicle i.p. at 1, 4, or 6â¯h after reperfusion onset. The time-course of brain histone H3 acetylation was studied. After tMCAO, drug brain penetrance and beneficial effects on behavioural outcomes, infarct volume, oedema, angiogenesis, blood-brain barrier integrity, cerebral artery oxidative stress and remodelling, and brain and vascular inflammation were evaluated. SAHA increased brain histone H3 acetylation from 1 to 6â¯h after injection, reaching the ischaemic brain administered during reperfusion. Treatment given at 4â¯h after reperfusion onset improved neurological score, reduced infarct volume and oedema, attenuated microglial activation, prevented exacerbated MCA angiogenic sprouting and blood-brain barrier breakdown, normalised MCA oxidative stress and remodelling, and modulated brain and cerebrovascular cytokine expression. Overall, we demonstrate that SAHA administered during early reperfusion exerts robust brain and vascular protection after tMCAO in hypertensive rats. These findings are aligned with previous research in ischaemic normotensive mice and help pave the way to optimise the design of clinical trials assessing the effectiveness and safety of SAHA in ischaemic stroke.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Ratos , Animais , Camundongos , Vorinostat/farmacologia , Vorinostat/uso terapêutico , Histona Desacetilases , Ratos Endogâmicos SHR , Isquemia Encefálica/tratamento farmacológico , Histonas , Acidente Vascular Cerebral/tratamento farmacológico , Encéfalo , Infarto , EdemaRESUMO
PMM2-CDG (MIM # 212065), the most common congenital disorder of glycosylation, is caused by the deficiency of phosphomannomutase 2 (PMM2). It is a multisystemic disease of variable severity that particularly affects the nervous system; however, its molecular pathophysiology remains poorly understood. Currently, there is no effective treatment. We performed an RNA-seq based transcriptomic study using patient-derived fibroblasts to gain insight into the mechanisms underlying the clinical symptomatology and to identify druggable targets. Systems biology methods were used to identify cellular pathways potentially affected by PMM2 deficiency, including Senescence, Bone regulation, Cell adhesion and Extracellular Matrix (ECM) and Response to cytokines. Functional validation assays using patients' fibroblasts revealed defects related to cell proliferation, cell cycle, the composition of the ECM and cell migration, and showed a potential role of the inflammatory response in the pathophysiology of the disease. Furthermore, treatment with a previously described pharmacological chaperone reverted the differential expression of some of the dysregulated genes. The results presented from transcriptomic data might serve as a platform for identifying therapeutic targets for PMM2-CDG, as well as for monitoring the effectiveness of therapeutic strategies, including pharmacological candidates and mannose-1-P, drug repurposing.
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Defeitos Congênitos da Glicosilação , Fibroblastos , Fosfotransferases (Fosfomutases) , Humanos , Defeitos Congênitos da Glicosilação/genética , Defeitos Congênitos da Glicosilação/patologia , Defeitos Congênitos da Glicosilação/metabolismo , Defeitos Congênitos da Glicosilação/tratamento farmacológico , Fosfotransferases (Fosfomutases)/genética , Fosfotransferases (Fosfomutases)/metabolismo , Fosfotransferases (Fosfomutases)/deficiência , Fibroblastos/metabolismo , Fibroblastos/patologia , Transcriptoma , Perfilação da Expressão Gênica , Proliferação de Células/genética , Proliferação de Células/efeitos dos fármacos , Feminino , Masculino , Movimento Celular/genética , Movimento Celular/efeitos dos fármacosRESUMO
Coenzyme Q (Q) is a key lipid electron transporter, but several aspects of its biosynthesis and redox homeostasis remain undefined. Various flavoproteins reduce ubiquinone (oxidized form of Q) to ubiquinol (QH2); however, in eukaryotes, only oxidative phosphorylation (OXPHOS) complex III (CIII) oxidizes QH2 to Q. The mechanism of action of CIII is still debated. Herein, we show that the Q reductase electron-transfer flavoprotein dehydrogenase (ETFDH) is essential for CIII activity in skeletal muscle. We identify a complex (comprising ETFDH, CIII and the Q-biosynthesis regulator COQ2) that directs electrons from lipid substrates to the respiratory chain, thereby reducing electron leaks and reactive oxygen species production. This metabolon maintains total Q levels, minimizes QH2-reductive stress and improves OXPHOS efficiency. Muscle-specific Etfdh-/- mice develop myopathy due to CIII dysfunction, indicating that ETFDH is a required OXPHOS component and a potential therapeutic target for mitochondrial redox medicine.
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Flavoproteínas Transferidoras de Elétrons , Fosforilação Oxidativa , Ubiquinona , Animais , Camundongos , Flavoproteínas Transferidoras de Elétrons/genética , Flavoproteínas Transferidoras de Elétrons/metabolismo , Homeostase , Lipídeos , Músculo Esquelético/metabolismo , Ubiquinona/metabolismoRESUMO
BACKGROUND: Ustekinumab (UST) is commonly used to treat Crohn's disease and ulcerative colitis. However, some patients may experience diminishing response or require increased dosage. Intravenous (IV) UST maintenance is explored as a solution. OBJECTIVES: We sought to evaluate IV UST maintenance effectiveness and safety in inflammatory bowel disease patients with partial or lost subcutaneous UST response. METHODS: This was a multicenter retrospective study of inflammatory bowel disease patients on IV UST maintenance. Clinical response and remission at weeks 12 and 52, defined as Harvey-Bradshaw Index ≤4 for Crohn's disease or partial Mayo score ≤2 for ulcerative colitis. Objective markers reduction (fecal calprotectin, C-reactive protein), UST trough levels pre- and post-IV maintenance, and adverse events were assessed. RESULTS: A total of 59 patients were included. Clinical remission at weeks 12 and 52 achieved by 47.5% and 64.3% respectively. 96.6% continued IV UST at follow-up. UST serum levels quadrupled. No adverse events reported. CONCLUSIONS: IV UST maintenance effectively sustained remission in most patients at 52 weeks.
When patients lose response to subcutaneous ustekinumab, strategies include reinduction, interval shortening, and less explored intravenous maintenance. Its high rescue rate and safety profile make it a valuable option for managing active inflammatory bowel disease.
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The ABC and ACMG variant classification systems were compared by asking mainly European clinical laboratories to classify variants in 10 challenging cases using both systems, and to state if the variant in question would be reported as a relevant result or not as a measure of clinical utility. In contrast to the ABC system, the ACMG system was not made to guide variant reporting but to determine the likelihood of pathogenicity. Nevertheless, this comparison is justified since the ACMG class determines variant reporting in many laboratories. Forty-three laboratories participated in the survey. In seven cases, the classification system used did not influence the reporting likelihood when variants labeled as "maybe report" after ACMG-based classification were included. In three cases of population frequent but disease-associated variants, there was a difference in favor of reporting after ABC classification. A possible reason is that ABC step C (standard variant comments) allows a variant to be reported in one clinical setting but not another, e.g., based on Bayesian-based likelihood calculation of clinical relevance. Finally, the selection of ACMG criteria was compared between 36 laboratories. When excluding criteria used by less than four laboratories (<10%), the average concordance rate was 46%. Taken together, ABC-based classification is more clear-cut than ACMG-based classification since molecular and clinical information is handled separately, and variant reporting can be adapted to the clinical question and phenotype. Furthermore, variants do not get a clinically inappropriate label, like pathogenic when not pathogenic in a clinical context, or variant of unknown significance when the significance is known.
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Variação Genética , Humanos , Testes Genéticos/normas , Testes Genéticos/métodosRESUMO
OBJECTIVE: To characterize and describe clinical experience with childhood-onset non-infectious uveitis. STUDY DESIGN: A multicenter retrospective multidisciplinary national web-based registry of 507 patients from 21 hospitals was analyzed. Cases were grouped as immune disease-associated (IMDu), idiopathic (IDIu) or ophthalmologically distinct. Characteristics of juvenile idiopathic arthritis-associated (non-HLA-B27-related) uveitis (JIAu), IDIu, and pars planitis (PP) were compared. RESULTS: IMDu (62.3%) and JIAu (51.9%) predominated in young females; and IDIu (22.7%) and PP (13.6%) in older children, without sex imbalance. Ocular complications occurred in 45.3% of cases (posterior synechiae [28%], cataracts [16%], band keratopathy [14%], ocular hypertension [11%] and cystoid macular edema [10%]) and were associated with synthetic (86%) and biologic (65%) disease-modifying antirheumatic drug (DMARD) use. Subgroups were significantly associated (p < 0.05) with different characteristics. JIAu was typically anterior (98%), insidious (75%), in ANA-positive (69%), young females (82%) with fewer complications (31%), better visual outcomes, and later use of uveitis-effective biologics. In contrast, IDIu was characteristically anterior (87%) or panuveitic (12.1%), with acute onset (60%) and more complications at onset (59%: synechiae [31%] and cataracts [9.6%]) and less DMARD use, while PP is intermediate, and was mostly bilateral (72.5%), persistent (86.5%) and chronic (86.8%), with more complications (70%; mainly posterior segment and cataracts at last visit), impaired visual acuity at onset, and greater systemic (81.2%), subtenon (29.1%) and intravitreal (10.1%) steroid use. CONCLUSION: Prognosis of childhood uveitis has improved in the "biologic era," particularly in JIAu. Early referral and DMARD therapy may reduce steroid use and improve outcomes, especially in PP and IDIu.
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Resumen: Esta investigación tiene como objetivos, por un lado, explorar las percepciones de las deportistas acerca de cómo son evaluadas por su entorno social con relación a la feminidad y a su orientación sexual por su vinculación con una práctica deportiva de alto rendimiento. Por otro, analizar la visibilidad y aceptación de la homosexualidad en el contexto deportivo tanto por las deportistas como por los agentes sociales que las rodean. La metodología fue de tipo cualitativo. Se llevaron a cabo cinco grupos focales en los que participaron 46 mujeres practicantes de futbol sala, balonmano, voleibol, atletismo y natación. Los resultados muestran que las deportistas presentan un discurso de resistencia frente al estereotipo de marimacho-lesbiana que, comprobamos, continúa vigente en el imaginario colectivo. A pesar de que se perciben avances sociales en este sentido, la homosexualidad sigue estigmatizada y aún persisten formas de rechazo cognitivo-afectivo en parte de la sociedad española.
Resumo: Esta pesquisa tem como objetivo, por um lado, explorar as percepções das atletas sobre como são avaliadas pelo seu ambiente social em relação à feminilidade e sua orientação sexual, para vincular-se a uma prática esportiva de alto desempenho e, por outro, analisar a visibilidade e aceitação da homossexualidade no contexto esportivo, tanto pelos atletas como pelos agentes sociais ao seu redor. A metodologia foi qualitativa. Foram feitos cinco grupos focais nos quais participaram 46 mulheres praticando futsal, handebol, vôlei, atletismo e natação. Os resultados mostram que as atletas apresentam um discurso de resistência contra o estereótipo da "Maria-João" o "sapatão" que, verificamos, ainda está em vigor na imaginação coletiva. Embora os avanços sociais sejam percebidos nesse sentido, a homossexualidade permanece estigmatizada e ainda persistem as formas de rejeição cognitivo-afetiva em parte da sociedade espanhola.
Abstract: On the one hand, this research aims to explore the perceptions of women practicing high-performance sports about how they are viewed by their social environment in terms of their femininity and sexual orientation. On the other hand, it analyzes the visibility and acceptance of homosexuality in the sports context by both athletes and the social agents surrounding them. The research methodology was qualitative, with five focus groups including 46 women who practiced futsal, handball, volleyball, athletics and swimming. Results show that they present a resistance-oriented discourse against butch-lesbian stereotypes that, as we prove, are still present in collective imagination. Despite social advances perceived in this regard, homosexuality remains stigmatized and forms of cognitive-affective rejection persist in part of Spanish society.
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Humanos , Feminino , Atletismo , Sexualidade , Feminilidade , Minorias Sexuais e de Gênero , Identidade de Gênero , Homossexualidade , Pesquisa QualitativaRESUMO
Abstract Genetic defects affecting the remethylation pathway cause hyperhomocysteinemia. Isolated remethylation defects are caused by mutations of the 5, 10-methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase(MTRR), methionine synthase(MTR), and MMADHC genes, and combined remethylation defects are the result of mutations in genes involved in the synthesis of either methylcobalamin or adenosylcobalamin, that is, the active cofactors of MTRR and methylmalonyl-CoA mutase. Diagnosis is based on the biochemical analysis of amino acids, homocysteine, propionylcarnitine, methylmalonic acid, S-adenosylmethionine, and 5-methylentetrahydrofolate in physiological fluids. Gene-by-gene Sanger sequencing has long been the gold standard genetic analysis for confirming the disorder and identifying the gene involved, but massive parallel sequencing is now being used to examine all those potentially involved in one go. Early treatment to rescue metabolic homeostasis is based on the following of an appropriate diet, betaine administration, and, in some cases, oral or intramuscular administration of vitamin B12 or folate. Elevated ROS levels, apoptosis, endoplasmic reticulum (ER) stress, the activation of autophagy, and alterations in Ca2+ homeostasis may all contribute toward the pathogenesis of the disease. Pharmacological agents to restore the function of the ER and mitochondria and/or to reduce oxidative stress-induced apoptosis might provide novel ways of treating patients with remethylation disorders.
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La aciduria metilmalónica es una acidemia orgánica, autosómica recesiva, causada por la deficiencia de la metilmalonil CoA-mutasa, o por defectos en la biosíntesis del cofactor adenosilcobalamina. Del defecto enzimático, existen dos formas: mut (o) sin actividad enzimática y mut (-) con actividad reducida. Su presentación clínica puede variar desde una forma neonatal grave con acidosis y muerte, hasta una forma crónica progresiva. A continuación se describe el caso de un niño de 4 años de edad, con deficiencia de metilmalonil-CoA mutasa tipo mut (-), que se presentó en forma aguda. El estudio molecular del gen MUT mostró 2 mutaciones c.607G>A (G203R) y c.2080C > T(R694W), confirmadas posteriormente en los padres. El objetivo de este reporte es destacar la importancia de indicar el análisis de ácidos orgánicos en orina entre los estudios de primera línea, en todo niño con un cuadro clínico de presentación aguda y severamente enfermo, sin etiología definida. Por otra parte, se desea resaltar que el diagnóstico oportuno y definitivo es importante ya que permite iniciar un tratamiento específico, lograr una evolución favorable y prevenir las secuelas.
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Humanos , Masculino , Feminino , Ácido Metilmalônico , Metilmalonil-CoA Mutase , Ácidos Orgânicos , Bioquímica , VenezuelaRESUMO
Se estudiaron los parámetros farmacocinéticos de las especies de antimonio (pentavalente y trivalente) presentes en el antimoniato de meglumina (Glucantime®), en cuatro perros sanos, después de la administración subcutánea de una dosis única de 90 mg/kg-1. Las muestras sanguíneas fueron analizadas por espectroscopia de absorción atómica. Después de la administración de Glucantime®, el antimonio pentavalente mostró un decaimiento en dos fases, la vida media de eliminación fue de 13,18 h, el volumen aparente de distribución de 30,65 Lkg-1, el área bajo la curva (0-24h) 48,25 μg. h mL-1 y el área bajo la curva (0-∞) μg.h mL-1. Mientras que el antimonio trivalente mostró una fase bien distinguida, con una vida media de eliminación de 16,10 h, un volumen aparente de distribución de 126,5 Lkg-1, valores de el área bajo la curva (0-24h) 10,35 μg.h L-1 y el área bajo la curva (0-∞) 7,35 μg.h mL-1. El porcentaje de conversión sistémica de antimonio pentavalente hacia antimonio trivalente a las 24 horas fue de 23,62%. A pesar del reducido tamaño de la muestra, los resultados obtenidos presentan desigualdad en la farmacocinética de las especies de antimonio en perros, estas podrían explicar, al menos parcialmente, las diferencias en la eficacia terapéutica atribuidas a las especies por separado.