Z Gastroenterol 2011; 49 - P5_19
DOI: 10.1055/s-0030-1269725

Accumulated fat in steatotic livers: effects on SREBP-2 expression and subsequent clinical outcomes

SML Lee 1, S Gashi 2, S Fröba 2, M Rentsch 3, KW Jauch 3, WE Thasler 1
  • 1Zentrum für Leberzellforschung, Klinikum Großhadern, München
  • 2Gewebebank der Chirurgischen Klinik und Poliklinik-Großhadern im Auftrag der Stiftung Human Tissue and Cell Research HTCR, München
  • 3Chirurgische Klinik und Poliklinik Klinikum Großhadern, München

Non-alcoholic fatty liver disease (NAFLD) ranges in severity from steatosis to non-alcoholic steatohepatitis with a potential for progression to cirrhosis and hepatocellular cancer, making NAFLD a serious public health problem. This study aimed to determine if amount of fat (total, macrovesicular and microvesicular) accumulated in the liver during steatosis is linked to increased SREBP-2 expression and to the subsequent clinical outcomes of the patients.

Annotated liver tissues were provided by the Grosshadern Hospital Tissue Bank. Briefly, patients were matched by BMI, age and gender. Liver sections were examined and classified according to the percentage of fat; control (no fat), low fat (less than 30% fat) and high fat (more than 30% fat). Relative SREBP-2 gene expression was then measured and follow-ups were done to document the clinical outcomes of the patients.

The high fat group had significantly higher relative SREBP-2 mRNA levels compared to controls and the low fat group by 3.0- and 2.4-fold respectively. It was also found that relative SREBP-2 mRNA levels were positively correlated to percent total fat and macrovesicular fat (P<0.01), but not to microvesicular fat (P>0.01). However, it appears that the accumulation of fat is not linked to rate and severity of complications from liver resections, hospitalisation time, blood loss, surgery duration, disease recurrence, metastasis to other organs and long-term survival (P>0.05).

In conclusion, fat and in particular macrovesicular fat accumulation is linked to relative SREBP-2 expression. Thus, SREBP-2, an enzyme of cholesterol metabolism, can potentially be used as a marker for staging steatosis. Knowing the fat accumulation in a timely fashion by PCR is important since livers with high macrovesicular fat exhibit high rates of graft dysfunction when transplanted. Further, it appears that fat accumulation at this early stage of NAFLD does not appear to be linked to the clinical outcomes investigated.