Exosomes: Potential Disease Biomarkers and New Therapeutic Targets.

Exosomes are extracellular vesicles released by cells, both constitutively and after cell activation, and are present in different types of biological fluid. Exosomes are involved in the pathogenesis of diseases, such as cancer, neurodegenerative diseases, pregnancy disorders and cardiovascular diseases, and have emerged as potential non-invasive biomarkers for the detection, prognosis and therapeutics of a myriad of diseases. In this review, we describe recent advances related to the regulatory mechanisms of exosome biogenesis, release and molecular composition, as well as their role in health and disease, and their potential use as disease biomarkers and therapeutic targets. In addition, the advantages and disadvantages of their main isolation methods, characterization and cargo analysis, as well as the experimental methods used for exosome-mediated drug delivery, are discussed. Finally, we present potential perspectives for the use of exosomes in future clinical practice.

Mitochondrial DNA deletion and duplication in Kearns-Sayre Syndrome (KSS) with initial presentation as Pearson Marrow-Pancreas Syndrome (PMPS): Two case reports in Barranquilla, Colombia.

BACKGROUND: Kearns-Sayre Syndrome (KSS) and Pearson Marrow-Pancreas Syndrome (PMPS) are among the classic phenotypes caused by mitochondrial DNA (mtDNA) deletions. KSS is a rare mitochondrial disease defined by a classic triad of progressive external ophthalmoplegia, atypical pigmentary retinopathy, and onset before 20 years. PMPS presents in the first year of life with bone marrow failure and exocrine pancreatic dysfunction, and can evolve into KSS later in life. Even though an mtDNA deletion is the most frequent mutation in KSS and PMPS, cases of duplications and molecular rearrangements have also been described. In Colombia, few case reports of KSS and PMPS have been published in indexed journals or have been registered in scientific events. METHODS: We discuss clinical and genetic aspects of two case reports of pediatric female patients, with initial clinical diagnosis of PMPS who later evolved into KSS, with confirmatory molecular studies of an mtDNA deletion and an mtDNA duplication. RESULTS: A large-scale mtDNA deletion, NC_012920.1:m.8286_14416del, was confirmed by Southern Blot in patient 1. An mtDNA duplication of 7.9 kb was confirmed by MLPA in patient 2. CONCLUSIONS: Our findings are compatible with the phenotypic and genetic presentation of PMPS and KSS. We present the first molecularly confirmed case reports of Colombian patients, diagnosed initially with PMPS, who later evolved to KSS.

Polimorfismos de los genes del sistema leptina-melanocortina asociados con la obesidad en la población adulta de Barranquilla / Polymorphisms of leptin-melanocortin system genes associated with obesity in an adult population from Barranquilla

Introducción. La obesidad se considera un grave problema de salud pública y por ello se hacen esfuerzos en la búsqueda de genes como el LEP, el LEPR y el MC4R del sistema leptina-melanocortina, el cual opera en la regulación neuroendocrina de la ingestión y el equilibrio energético e influye en la patogenia de la enfermedad. Los resultados contradictorios en torno a la asociación de estos genes con la obesidad plantean la necesidad de nuevas investigaciones. Objetivo. Analizar los polimorfismos rs2167270 del gen LEP, rs1137101 del gen LEPR y rs17782313 del gen MC4R asociados con la obesidad y sus variables clínicas y bioquímicas en una muestra de pacientes adultos de Barranquilla. Materiales y métodos. Se estudiaron 111 personas obesas y 155 no obesas como controles. Los polimorfismos se determinaron mediante reacción en cadena de la polimerasa (PCR) en tiempo real. Se tomaron las medidas antropométricas, se evaluó la presión arterial y se hicieron pruebas bioquímicas. Resultados. No se encontraron diferencias estadísticas en la frecuencia alélica y genotípica de los polimorfismos en los grupos estudiados. En cuanto a las variables clínicas y bioquímicas, el genotipo CC del polimorfismo rs17782313 del gen MC4R, se asoció con un aumento de la presión arterial sistólica y, el alelo T y su genotipo homocigoto, con una disminución del colesterol HDL en los obesos. No se evidenció ningún efecto de los otros polimorfismos en estas variables. Conclusiones. Los polimorfismos rs2167270 del gen LEP, rs1137101 del gen LEPR y rs17782313 del gen MC4R, no se asociaron con obesidad en la población analizada. Se encontró que el polimorfismo rs17782313 del gen MC4R influyó en el aumento de la presión arterial sistólica y la disminución del colesterol HDL en las personas obesas.

Introduction: Obesity is considered a serious public health problem. Efforts have been directed to search for candidate genes such as LEP, LEPR, and MC4R involved in the leptin- melanocortin system. The neuroendocrine regulation of these genes on energy intake and balance influences the pathogenesis of this disease. Contradictory results regarding the association of these genes with obesity raise the need for new research. Objective: To analyze the association between obesity and LEP rs2167270, LEPR rs1137101, and MC4R rs17782313 polymorphisms and the clinical and biochemical variables in obese adults from Barranquilla, Colombia. Materials and methods: We analyzed 111 obese adults and 155 non-obese individuals as controls. The polymorphisms were determined by real-time PCR. Besides, anthropometric measures, blood pressure, and biochemical tests were evaluated. Results: No statistical differences were found in allele and genotype frequencies of gene polymorphisms between groups. The CC genotype of MC4R rs17782313 polymorphism was associated with increased systolic blood pressure and T allele and TT genotype, with decreased HDL cholesterol in obese adults. The effect of the other polymorphisms on these variables was not evidenced. Conclusions: LEP rs2167270, LEPR rs1137101, and MC4R rs17782313 polymorphisms were not associated with obesity in the population under study. MC4R rs17782313 polymorphisms were associated with an increase in systolic blood pressure and a decrease in HDL cholesterol.

Síndrome de Townes-Brocks en Barranquilla, Colombia: Reporte de caso y estado del arte / Townes-Brocks Syndrome in Barranquilla, Colombia: Case report and state of the art

RESUMEN El síndrome de Townes-Brocks, descrito por primera vez en 1972, se caracteriza por tres anomalías congénitas mayores: malformación anorrectal, orejas displásicas y malformaciones del pulgar. Es un trastorno genético raro con herencia autosómica dominante y una prevalencia estimada de 1/250 0000, registrándose aproximadamente 164 casos en la literatura. En Colombia, solo un caso ha sido registrado en un evento científico, y este sería el primer caso publicado en una revista indexada. El objetivo de nuestro artículo es reportar el fenotipo del paciente y el estado actual del arte del síndrome de Townes-Brocks.

ABSTRACT Townes-Brocks syndrome, described in 1972, is characterized by three major congenital anomalies: anorectal malformation, dysplastic ears and thumb anomalies. It is a rare genetic disorder with autosomal dominant inheritance and an estimated prevalence of 1/250.0000. Approximately 164 cases have been reported in the literature. In Colombia, only one case was previously reported in a scientific event. Our case report is the first published in an indexed journal. Our article aims to report the patient's phenotype and the state of art of Townes-Brocks syndrome.

Síndrome de Kabuki: presentación de un Caso y Revisión de la Literatura / Kabuki Syndrome: A case report and literature review

Resumen El síndrome de Kabuki (SK) es una patología muy rara, descrita por primera vez en 1981 por Niikawa y Kuroki en Japón. Se han publicado cerca de 400 casos a nivel mundial. En Colombia se conocen cinco casos diagnosticados y publicados; el caso objeto de este estudio sería el sexto en nuestro país. Presentamos la descripción del caso de una paciente de 2 años y 6 meses con rasgos dismórficos compatibles con síndrome de Kabuki. Examen físico: fisuras palpebrales elongadas, eversión del tercio lateral párpado inferior, cejas arqueadas con tercio lateral más despoblado, puente nasal deprimido, boca en carpa, paladar hendido, pabellones auriculares de baja implantación con rotación posterior. El síndrome de Kabuki se caracteriza por sus anomalías faciales peculiares que se consideran son la única manifestación que puede orientar al diagnóstico del mismo sin excepciones. Recientemente se han identificado mutaciones sin sentido y de corrimiento del marco de lectura, entre otras en el gen MLL2 en aproximadamente el 75 % de los casos y en una menor proporción deleciones y mutaciones sin sentido en el gen KDM6A.

Abstract Kabuki syndrome is a rare disease described by Kuroki and Niikawa in Japanese population in 1981. There are over 400 cases over the world and 5 cases described in Colombian population. Therefore this is the 6th Kabuki syndrome found in Colombia. We report a 2 years old female with Kabuki syndrome phenotype. Clinical examination showed: long palpebral fissures with eversion of the lateral third of the lower eyelids, a broad and depressed nasal tip, left palate and low setup ears. Kabuki syndrome includes facial features whit specific characteristics enough to classify the patients. However, there are some mutations in MLL2 gene present in almost 75 % of Kabuki syndrome. In addition there are some deletion and duplications abnormalities in KMD6A gene described in Kabuki syndrome patients.