PTEN Down-Regulation Promotes β-Oxidation to Fuel Hypertrophic Liver Growth After Hepatectomy in Mice.

Kachaylo, Ekaterina; Tschuor, Christoph; Calo, Nicolas; Borgeaud, Nathalie; Ungethüm, Udo; Limani, Perparim; Piguet, Anne Christine; Dufour, Jean-François; Foti, Michelangelo; Graf, Rolf; Clavien, Pierre A; Humar, Bostjan (2017). PTEN Down-Regulation Promotes β-Oxidation to Fuel Hypertrophic Liver Growth After Hepatectomy in Mice. Hepatology, 66(3), pp. 908-921. Wiley Interscience 10.1002/hep.29226

[img] Text
Kachaylo_et_al-2017-Hepatology.pdf - Published Version
Restricted to registered users only
Available under License Publisher holds Copyright.

Download (2MB) | Request a copy

In regenerating liver, hepatocytes accumulate lipids before the major wave of parenchymal growth. This transient, regeneration-associated steatosis (TRAS) is required for liver recovery, but its purpose is unclear. The tumor suppressor phosphatase and tensin homolog (PTEN) is a key inhibitor of the protein kinase B/mammalian target of rapamycin axis that regulates growth and metabolic adaptations after hepatectomy. In quiescent liver, PTEN causes pathological steatosis when lost, whereas its role in regenerating liver remains unknown. Here, we show that PTEN down-regulation promotes liver growth in a TRAS-dependent way. In wild-type mice, PTEN reduction occurred after TRAS formation, persisted during its disappearance, and correlated with up-regulated β-oxidation at the expense of lipogenesis. Pharmacological modulation revealed an association of PTEN with TRAS turnover and hypertrophic liver growth. In liver-specific Pten(-/-) mice shortly after induction of knockout, hypertrophic regeneration was accelerated and led to hepatomegaly. The resulting surplus liver mass was functional, as demonstrated by raised survival in a lethal model of resection-induced liver failure. Indirect calorimetry revealed lipid oxidation as the primary energy source early after hepatectomy. The shift from glucose to lipid usage was pronounced in Pten(-/-) mice and correlated with the disappearance of TRAS. Partial inhibition of β-oxidation led to persisting TRAS in Pten(-/-) mice and abrogated hypertrophic liver growth. PTEN down-regulation may promote β-oxidation through β-catenin, whereas hypertrophy was dependent on mammalian target of rapamycin complex 1. CONCLUSION PTEN down-regulation after hepatectomy promotes the burning of TRAS-derived lipids to fuel hypertrophic liver regeneration. Therefore, the anabolic function of PTEN deficiency in resting liver is transformed into catabolic activities upon tissue loss. These findings portray PTEN as a node coordinating liver growth with its energy demands and emphasize the need of lipids for regeneration. (Hepatology 2017;66:908-921).

Item Type:

Journal Article (Original Article)

Division/Institute:

04 Faculty of Medicine > Department of Gastro-intestinal, Liver and Lung Disorders (DMLL) > Clinic of Visceral Surgery and Medicine > Hepatology
04 Faculty of Medicine > Pre-clinic Human Medicine > BioMedical Research (DBMR) > DBMR Forschung Mu35 > Forschungsgruppe Hepatologie
04 Faculty of Medicine > Pre-clinic Human Medicine > BioMedical Research (DBMR) > DBMR Forschung Mu35 > Forschungsgruppe Hepatologie

UniBE Contributor:

Piguet, Anne Christine and Dufour, Jean-François

Subjects:

600 Technology > 610 Medicine & health

ISSN:

0270-9139

Publisher:

Wiley Interscience

Language:

English

Submitter:

Thi Thao Anh Pham

Date Deposited:

11 Dec 2017 15:08

Last Modified:

11 Dec 2017 15:08

Publisher DOI:

10.1002/hep.29226

PubMed ID:

28437835

BORIS DOI:

10.7892/boris.107127

URI:

https://boris.unibe.ch/id/eprint/107127

Actions (login required)

Edit item Edit item
Provide Feedback