Background: Both hepatic (HF) and visceral fat (VF) are involved in the onset and progression of metabolic syndrome and NAFLD. However, their relative role is still debated. Aim: To determine the relative contribution of HF and VF to both metabolic derangements and histological liver damage in NAFLD patients. Methods: In 22 non-diabetic, non-dyslipidaemic patients with biopsy-proven NAFLD we measured whole abdomen VF by MRI, fasting endogenous glucose production (EGP) and lipolysis by tracer infusion, peripheral insulin resistance (IR) as HOMA, Hepatic-IR (EGP*insulin) and Adipo-IR (FFA*Insulin). Hepatic histology was scored according to Kleiner, HF was assessed as percentage of liver fat. Results: VF increased with BMI (r=0.54, p<0.004) and HF (r=0.43, p<0.03), whereas HF was not correlated with BMI. Only HF, but not VF, was associated with circulating FFA levels (r=0.51, p<0.01), and Adipo-IR (r=0.41, p<0.05), while no correlation was found between either LF% or VF with Hepatic-IR or HOMA. Patients with NAS score ≥4 (vs. NAS 0–3) had increased VF (3.9±0.7 vs. 2.8±0.4 kg), FFA concentrations (525±52 vs. 804±98 mmol/l), peripheral IR (HOMA: 3.7±0.5 vs. 2.8±0.8), Hepatic-IR (169±23 vs. 124±32), and Adipo-IR (13.2±2.5 vs. 6.3±1.8) (all p<0.05). Considering only balloning and lobular inflammation in the NAS score, subjects with a composite score >2 had an impaired lipolysis suppression. Patients with fibrosis vs. those without fibrosis, had increased VF (3.9±0.6 vs. 2.7±0.7 kg, p<0.03), but not HF, and no differences were found in the indexes of IR. Conclusions: In NAFLD subjects, hepatic fat is associated with metabolic derangements and IR, but Adipo-IR and visceral fat accumulation appear to provide a major contribution to liver damage.

Contribution of visceral fat and hepatic fat to metabolic derangements and liver damage in NAFLD patients.

VANNI, Ester;ROSSO, CHIARA;GAMBINO, Roberto;FALETTI, Riccardo;CASSADER, Maurizio;SMEDILE, Antonina;RIZZETTO, Mario;BUGIANESI, Elisabetta
2013

Abstract

Background: Both hepatic (HF) and visceral fat (VF) are involved in the onset and progression of metabolic syndrome and NAFLD. However, their relative role is still debated. Aim: To determine the relative contribution of HF and VF to both metabolic derangements and histological liver damage in NAFLD patients. Methods: In 22 non-diabetic, non-dyslipidaemic patients with biopsy-proven NAFLD we measured whole abdomen VF by MRI, fasting endogenous glucose production (EGP) and lipolysis by tracer infusion, peripheral insulin resistance (IR) as HOMA, Hepatic-IR (EGP*insulin) and Adipo-IR (FFA*Insulin). Hepatic histology was scored according to Kleiner, HF was assessed as percentage of liver fat. Results: VF increased with BMI (r=0.54, p<0.004) and HF (r=0.43, p<0.03), whereas HF was not correlated with BMI. Only HF, but not VF, was associated with circulating FFA levels (r=0.51, p<0.01), and Adipo-IR (r=0.41, p<0.05), while no correlation was found between either LF% or VF with Hepatic-IR or HOMA. Patients with NAS score ≥4 (vs. NAS 0–3) had increased VF (3.9±0.7 vs. 2.8±0.4 kg), FFA concentrations (525±52 vs. 804±98 mmol/l), peripheral IR (HOMA: 3.7±0.5 vs. 2.8±0.8), Hepatic-IR (169±23 vs. 124±32), and Adipo-IR (13.2±2.5 vs. 6.3±1.8) (all p<0.05). Considering only balloning and lobular inflammation in the NAS score, subjects with a composite score >2 had an impaired lipolysis suppression. Patients with fibrosis vs. those without fibrosis, had increased VF (3.9±0.6 vs. 2.7±0.7 kg, p<0.03), but not HF, and no differences were found in the indexes of IR. Conclusions: In NAFLD subjects, hepatic fat is associated with metabolic derangements and IR, but Adipo-IR and visceral fat accumulation appear to provide a major contribution to liver damage.
46th Annual Meeting of the Italian Association for the Study of the Liver - AISF
Roma
21-22 Febbraio 2013
Suppl.1
S3
S4
L. Mezzabotta; E. Vanni; C. Rosso; S. Carenzi; R. Gambino; M. Gaggini; D. Lucarelli; R. Faletti; M. Cassader; A. Smedile; M. Rizzetto; A. Gastaldelli; E. Bugianesi
File in questo prodotto:
File Dimensione Formato  
Contribution of visceral fat and hepatic fat to metabolic derangements and liver damage in NAFLD patients.pdf

Accesso aperto con embargo fino al 05/04/2013

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 75.09 kB
Formato Adobe PDF
75.09 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/130535
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact