El arsénico, ese conocido tan desconocido

Una reciente publicación científica en la prestigiosa revista “Science” abogaba por la aparición de otro tipo de forma de vida (“extraterrestre” se ha dicho) basándose en la aparente abundancia de resultados proporcionados por el descubrimiento de una bacteria que aparentemente había sustituido el fósforo, uno de los elementos esenciales para la vida, tal cual la conocemos, por el arsénico (Wolfe-Simon et al., 2010). Dado que este asunto supone un tema complejo, incluso para personas que estamos dentro de este campo de la ciencia, en este “Baúl de la ciencia” se pretende explicar de la forma más sencilla posible cuál es el papel del arsénico en la naturaleza y cómo este elemento interacciona negativamente con los seres vivos. Desde este conocimiento básico tendremos más fundamentos para avalar o refutar la existencia de una forma de vida diferente a la convencional que describen los autores de la publicació

Mycoredoxins Are Required for Redox Homeostasis and Intracellular Survival in the Actinobacterial Pathogen Rhodococcus equi

[EN] Rhodococcus equi is a facultative intracellular pathogen that can survive within macrophages of a wide variety of hosts, including immunosuppressed humans. Current antibiotherapy is often ineffective, and novel therapeutic strategies are urgently needed to tackle infections caused by this pathogen. In this study, we identified three mycoredoxin-encoding genes (mrx) in the genome of R. equi, and we investigated their role in virulence. Importantly, the intracellular survival of a triple mrx-null mutant (Δmrx1Δmrx2Δmrx3) in murine macrophages was fully impaired. However, each mycoredoxin alone could restore the intracellular proliferation rate of R. equi Δmrx1Δmrx2Δmrx3 to wild type levels, suggesting that these proteins could have overlapping functions during host cell infection. Experiments with the reduction-oxidation sensitive green fluorescent protein 2 (roGFP2) biosensor confirmed that R. equi was exposed to redox stress during phagocytosis, and mycoredoxins were involved in preserving the redox homeostasis of the pathogen. Thus, we studied the importance of each mycoredoxin for the resistance of R. equi to different oxidative stressors. Interestingly, all mrx genes did have overlapping roles in the resistance to sodium hypochlorite. In contrast, only mrx1 was essential for the survival against high concentrations of nitric oxide, while mrx3 was not required for the resistance to hydrogen peroxide. Our results suggest that all mycoredoxins have important roles in redox homeostasis, contributing to the pathogenesis of R. equi and, therefore, these proteins may be considered interesting targets for the development of new anti-infectivesS

Understanding microRNAs in the Context of Infection to Find New Treatments against Human Bacterial Pathogens

[EN] The development of RNA-based anti-infectives has gained interest with the successful application of mRNA-based vaccines. Small RNAs are molecules of RNA of <200 nucleotides in length that may control the expression of specific genes. Small RNAs include small interference RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), or microRNAs (miRNAs). Notably, the role of miRNAs on the post-transcriptional regulation of gene expression has been studied in detail in the context of cancer and many other genetic diseases. However, it is also becoming apparent that some human miRNAs possess important antimicrobial roles by silencing host genes essential for the progress of bacterial or viral infections. Therefore, their potential use as novel antimicrobial therapies has gained interest during the last decade. The challenges of the transport and delivery of miRNAs to target cells are important, but recent research with exosomes is overcoming the limitations in RNA-cellular uptake, avoiding their degradation. Therefore, in this review, we have summarised the latest developments in the exosomal delivery of miRNA-based therapies, which may soon be another complementary treatment to pathogen-targeted antibiotics that could help solve the problem caused by multidrug-resistant bacteriaSIWe thank the Junta de Castilla y León (Spain) for funding our research work on microRNAs, grant number LE044P20. A.M. is supported with a postdoctoral fellowship “Margarita Salas”. M.L. is the recipient of a “Beatriz Galindo” grant (Ref. BEAGAL18/00068 - BGP18/00033

Aprendizaje-Servicio en el entorno rural de León

[ES] A través del grupo de Innovación Docente BIOMETAC, nace esta experiencia de ApS para promover en los estudiantes de los grados en Biología, Biotecnología y Ciencias Ambientales de la ULE, la iniciativa cívica de participación en la sociedad. El objetivo general del proyecto es que el alumnado aplique sus conocimientos y habilidades para sensibilizar y dinamizar a la población de varios municipios rurales de León frente a retos de la Agenda 2030 asociados a la salud y la sostenibilidad ambiental. Se establecieron 3 grupos de trabajo, cada uno integrado por 12 estudiantes de los tres grados, que trabajan en 3 municipios rurales de la provincia de León: Cistierna, Truchas y Villablino, con diversas problemáticas en el ámbito de la salud y medioambiente. El Proyecto se realiza en tres fases: Preparación, Ejecución y Evaluación y Difusión. Durante la primera fase (curso 2021/22), se realizaron reuniones con el alumnado para guiarlos en el diagnóstico de cada municipio. Los datos obtenidos permitieron detectar los problemas que más preocupaban a la población de cada municipio. En una segunda fase (curso 2022/23), los alumnos profundizarán en las distintas problemáticas mediante actuaciones propuestas por ellos mismos y presentarán sus conclusiones en cada municipio. Esta experiencia pretende que los estudiantes pongan los conocimientos y las competencias adquiridas al servicio de comunidades rurales, trabajando directamente sobre varios Objetivos de Desarrollo Sostenible (ODS), mejorando su capacidad de iniciativa, autonomía en la organización del trabajo, y responsabilidad para la resolución de problemas

RICORS2040 : The need for collaborative research in chronic kidney disease

Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true