Splicing Factor SLU7 Prevents Oxidative Stress-Mediated Hepatocyte Nuclear Factor 4α Degradation, Preserving Hepatic Differentiation and Protecting From Liver Damage

Background and Aims: Hepatocellular dedifferentiation is emerging as an important determinant in liver disease progression. Preservation of mature hepatocyte identity relies on a set of key genes, predominantly the transcription factor hepatocyte nuclear factor 4α (HNF4α) but also splicing factors like SLU7. How these factors interact and become dysregulated and the impact of their impairment in driving liver disease are not fully understood. Approach and Results: Expression of SLU7 and that of the adult and oncofetal isoforms of HNF4α, driven by its promoter 1 (P1) and P2, respectively, was studied in diseased human and mouse livers. Hepatic function and damage response were analyzed in wild-type and Slu7-haploinsufficient/heterozygous (Slu7) mice undergoing chronic (CCl) and acute (acetaminophen) injury. SLU7 expression was restored in CCl-injured mice using SLU7-expressing adeno-associated viruses (AAV-SLU7). The hepatocellular SLU7 interactome was characterized by mass spectrometry. Reduced SLU7 expression in human and mouse diseased livers correlated with a switch in HNF4α P1 to P2 usage. This response was reproduced in Slu7 mice, which displayed increased sensitivity to chronic and acute liver injury, enhanced oxidative stress, and marked impairment of hepatic functions. AAV-SLU7 infection prevented liver injury and hepatocellular dedifferentiation. Mechanistically we demonstrate a unique role for SLU7 in the preservation of HNF4α1 protein stability through its capacity to protect the liver against oxidative stress. SLU7 is herein identified as a key component of the stress granule proteome, an essential part of the cell’s antioxidant machinery. Conclusions: Our results place SLU7 at the highest level of hepatocellular identity control, identifying SLU7 as a link between stress-protective mechanisms and liver differentiation. These findings emphasize the importance of the preservation of hepatic functions in the protection from liver injury.Supported by MINECO/AEI/FEDER (UE SAF2016-75972-R, PID2019-104265RB-I00/AEI/10.13039/501100011033, and PID2019-104878RB-100/AEI/10.13039/501100011033), CIBERehd, Fundación La Caixa (HEPACARE), an AECC postdoctoral fellowship (POSTD18014AREC, to M.A.), a Ministerio de Educación FPU fellowship (FPU18/01461, to M.G.R.), a Ministerio de Educación FPI fellowship (BES-2017-079883, to M.R.); a Ramón y Cajal Program contract (RYC2018-024475-1, to M.G.F.B.), the Fundación Eugenio Rodríguez Pascual, the Fundación Mario Losantos, the Fundación M. Torres, and a generous donation from Mr. Eduardo Avila

Heterologous Prime-Boost Oral Immunization with GK-1 Peptide from Taenia crassiceps Cysticerci Induces Protective Immunity▿

Oral immunization is a goal in vaccine development, particularly for pathogens that enter the host through the mucosal system. This study was designed to explore the immunogenic properties of the Taenia crassiceps protective peptide GK-1 administered orally. Mice were orally immunized with the synthetic GK-1 peptide in its linear form with or without the Brucella lumazine synthase (BLS) protein adjuvant or as a chimera recombinantly bound to BLS (BLS-GK-1). Mice were boosted twice with GK-1 only at 15-day intervals. A significant rate of protection of 64.7% was achieved in GK-1-immunized mice, and that rate significantly increased to 91.8 and 96% when mice were primed with GK-1 coadministered with BLS as an adjuvant and BLS as a carrier, respectively. Specific antibodies and T cell activation and proliferation accompanied the protection induced, revealing the potent immunogenicity of GK-1. Through immunohistochemical studies, GK-1 was detected in T and B cell zones of the Peyer's patches (PP) and mesenteric lymph nodes. In the latter, abundant proliferating cells were detected by 5′-bromo-2′-deoxyuridine incorporation. No proliferation was detected in PP. Altogether, these results portray the potent immunogenic properties of GK-1 administered orally and reinforce the usefulness of BLS as an adjuvant and adequate vaccine delivery system for oral vaccines

Atención integral del neonato con encefalopatía hipóxico-isquémica en España

Introducción Apenas conocemos cómo es la asistencia de los recién nacidos (RN) con encefalopatía hipóxico-isquémica (EHI) en hipotermia terapéutica (HT), especialmente si existen protocolos asistenciales, la neuromonitorización que se realiza o cómo es la aproximación al pronóstico neurológico. Este conocimiento permite detectar e implementar áreas de mejora asistencial. Método Estudio transversal de los 57 hospitales españoles que realizaban HT en 2015, mediante cuestionario sobre: 1) la disponibilidad de protocolos y de recursos tecnológicos; 2) el uso de herramientas de neuromonitorización; 3) los conocimientos de los profesionales; 4) la información pronóstica que se da los padres, y 5) el informe al alta y del plan de seguimiento. Resultados El 95% utiliza enfriamiento corporal-total servocontrolado y dispone de protocolos específicos de actuación. El 70% utiliza sedación y el 68% deja al paciente a dieta absoluta. La monitorización con electroencefalografía integrada por amplitud se utiliza en más del 80% de los centros, aunque solo en el 50% la enfermera es capaz de interpretarlo. La saturación de oxígeno cerebral es escasamente monitorizada (16%). Entre los estudios diagnóstico-pronósticos, la neuroimagen es universal, pero los neurobiomarcadores apenas se utilizan (29%). Solo el 21% ofrece información pronóstica antes de las 72 h de vida; sin presencia de la enfermera en el 70%. El seguimiento lo realiza el neuropediatra (84%), con una duración desigual entre centros. Conclusiones La asistencia del RN con EHI en España es adecuada, con áreas de mejora en: neuromonitorización, sedación, marco temporal de la información pronóstica, trabajo en equipo y estandarización de la duración del seguimiento