Boosting mitochondria activity by silencing MCJ overcomes cholestasis-induced liver injury

Background & Aims: Mitochondria are the major organelles for the formation of reactive oxygen species (ROS) in the cell, and mitochondrial dysfunction has been described as a key factor in the pathogenesis of cholestatic liver disease. The methylation-controlled J-protein (MCJ) is a mitochondrial protein that interacts with and represses the function of complex I of the electron transport chain. The relevance of MCJ in the pathology of cholestasis has not yet been explored. Methods: We studied the relationship between MCJ and cholestasis-induced liver injury in liver biopsies from patients with chronic cholestatic liver diseases, and in livers and primary hepatocytes obtained from WT and MCJ-KO mice. Bile duct ligation (BDL) was used as an animal model of cholestasis, and primary hepatocytes were treated with toxic doses of bile acids. We evaluated the effect of MCJ silencing for the treatment of cholestasis-induced liver injury. Results: Elevated levels of MCJ were detected in the liver tissue of patients with chronic cholestatic liver disease when compared with normal liver tissue. Likewise, in mouse models, the hepatic levels of MCJ were increased. After BDL, MCJ-KO animals showed significantly decreased inflammation and apoptosis. In an in vitro model of bile-acid induced toxicity, we observed that the loss of MCJ protected mouse primary hepatocytes from bile acid-induced mitochondrial ROS over-production and ATP depletion, enabling higher cell viability. Finally, the in vivo inhibition of the MCJ expression, following BDL, showed reduced liver injury and a mitigation of the main cholestatic characteristics. Conclusions: We demonstrated that MCJ is involved in the progression of cholestatic liver injury, and our results identified MCJ as a potential therapeutic target to mitigate the liver injury caused by cholestasis. Lay summary: In this study, we examine the effect of mitochondrial respiratory chain inhibition by MCJ on bile acid-induced liver toxicity. The loss of MCJ protects hepatocytes against apoptosis, mitochondrial ROS overproduction, and ATP depletion as a result of bile acid toxicity. Our results identify MCJ as a potential therapeutic target to mitigate liver injury in cholestatic liver diseases.Acknowledgements: We thank MINECO for the Severo Ochoa Excellence Accreditation of CIC bioGUNE [SEV-2016-0644]

Hepatitis aguda como única manifestación de sífilis en un paciente inmunocompetente

La sífilis es una infección crónica transmitida fundamentalmente por vía sexual que se caracteriza por presentar gran variedad de manifestaciones clínicas. La afectación hepática es poco habitual y suele acontecer en pacientes infectados por el virus de la inmunodeficiencia humana. Presentamos el caso de un varón de 42 años inmunocompetente con un cuadro clínico de hepatitis aguda colestásica por sífilis. La hepatitis aguda fue la única manifestación que presentó el paciente de secundarismo luético dificultando el diagnóstico. Consideramos importante incluir a la sífilis en el diagnóstico diferencial de la alteración del perfil hepático especialmente en pacientes con factores de riesgo dada su reversibilidad con tratamiento antibiótico adecuado

Early predictors of corticosteroid response in acute severe autoimmune hepatitis: a nationwide multicenter study

Background and aims: To assess whether corticosteroids improve prognosis in patients with AS-AIH, and to identify factors at therapy initiation and during therapy predictive of the response to corticosteroids. Methods: This was a retrospective cohort study including all patients with AS-AIH admitted to 13 tertiary centres from January 2002 to January 2019. The composite primary outcome was death or liver transplantation within 90 days of admission. Kaplan-Meier and Cox regression methods were used for data analysis. Results: Of 242 consecutive patients enrolled (mean age [SD] 49.7 [16.8] years), 203 received corticosteroids. Overall 90-day transplant-free survival was 61.6% (95% confidence interval [CI] 55.4-67.7). Corticosteroids reduced the risk of a poor outcome (adjusted hazard ratio [HR] 0.25; 95% CI 0.2-0.4), but this treatment failed in 30.5%. An internally validated nomogram composed of older age, MELD, encephalopathy and ascites at the initiation of corticosteroids accurately predicted the response (C-index 0.82; [95% CI 0.8-0.9]). In responders, MELD significantly improved from days 3 to 14 but remained unchanged in non-responders. MELD on day 7 with a cut-off of 25 (sensitivity 62.5%[95% CI: 47.0-75.8]; specificity 95.2% [95% CI: 89.9-97.8]) was the best univariate predictor of the response. Prolonging corticosteroids did not increase the overall infection risk (adjusted HR 0.75; 95% CI 0.3-2.1). Conclusion: Older patients with high MELD, encephalopathy or ascites at steroid therapy initiation and during treatment are unlikely to show a favourable response and so prolonged therapy in these patients, especially if they are transplantation candidates, should be avoided.This study was supported in part by grants from the Spanish Ministry of Science and Innovation, Instituto de Salud Carlos III, number PI20/01302, awarded to Agustín Albillos and number PI 21/01310, awarded to Luis Téllez. CIBEREHD is funded by the Instituto de Salud Carlos III using grants cofinanced by the European Development Regional Fund “A way to achieve Europe” (EDRF). María Carlota Londoño received support from the Plan Nacional de I+D+I co-funded by ISCIII-Subdirección General de Evaluación and Fondo Europeo de Desarrollo Regional (FEDER-"Una manera de Hacer Europa") (PI17/00955). Laura Patricia Llovet received the Resident Award “Clínic-La Pedrera” granted by the Hospital Clínic de Barcelona, Research, Innovation and Education Department