Intravascular hemolysis triggers NAFLD characterized by a deregulation of lipid metabolism and lipophagy blockade

© 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland..

Intravascular hemolysis is a common feature of different clinical entities, including sickle cell disease and malaria. Chronic hemolytic disorders are associated with hepatic damage; however, it is unknown whether heme disturbs lipid metabolism and promotes liver steatosis, thereby favoring the progression to nonalcoholic fatty liver disease (NAFLD). Using an experimental model of acute intravascular hemolysis, we report here the presence of liver injury in association with microvesicular lipid droplet deposition. Hemolysis promoted serum hyperlipidemia and altered intrahepatic triglyceride fatty acid composition, with increments in oleic, palmitoleic, and palmitic acids. These findings were related to augmented expression of transporters involved in fatty acid uptake (CD36 and MSR1) and deregulation of LDL transport, as demonstrated by decreased levels of LDL receptor and increased PCSK9 expression. Hemolysis also upregulated hepatic enzymes associated with cholesterol biosynthesis (SREBP2, HMGC1, LCAT, SOAT1) and transcription factors regulating lipid metabolism (SREBP1). Increased LC3II/LC3I ratio and p62/SQSTM1 protein levels were reported in mice with intravascular hemolysis and hepatocytes stimulated with heme, indicating a blockade of lipophagy. In cultured hepatocytes, cell pretreatment with the autophagy inductor rapamycin diminished heme-mediated toxicity and accumulation of lipid droplets. In conclusion, intravascular hemolysis enhances liver damage by exacerbating lipid accumulation and blocking the lipophagy pathway, thereby promoting NAFLD. These new findings have a high translational potential as a novel NAFLD-promoting mechanism in individuals suffering from severe hemolysis episodes. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:261

Enthalten in:

The Journal of pathology - 261(2023), 2 vom: 18. Okt., Seite 169-183

Sprache:

Englisch

Beteiligte Personen:

Rayego-Mateos, Sandra [VerfasserIn]
Morgado-Pascual, José Luis [VerfasserIn]
García-Caballero, Cristina [VerfasserIn]
Lazaro, Iolanda [VerfasserIn]
Sala-Vila, Aleix [VerfasserIn]
Opazo-Rios, Lucas [VerfasserIn]
Mas-Fontao, Sebastian [VerfasserIn]
Egido, Jesús [VerfasserIn]
Ruiz-Ortega, Marta [VerfasserIn]
Moreno, Juan Antonio [VerfasserIn]

Links:

Volltext

Themen:

42VZT0U6YR
EC 3.4.21.-
Fatty Acids
Heme
Intravascular hemolysis
Journal Article
Lipid accumulation
Lipid metabolism
Lipophagy
Liver damage
NAFLD
PCSK9 protein, human
Proprotein Convertase 9
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 05.09.2023

Date Revised 07.09.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1002/path.6161

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM360549993