In:
The Journal of Clinical Endocrinology & Metabolism, The Endocrine Society, Vol. 95, No. 6 ( 2010-06-01), p. 3039-3047
Abstract:
Context: Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in Western and non-Western countries, but its pathogenesis is not fully understood. Objective: Based on the role of nicotinamide phosphoribosyltransferase (NAMPT) in fat and glucose metabolism and cell survival, we hypothesized a role for NAMPT/visfatin in the pathogenesis of NAFLD-related disease. Design and Setting: We conducted clinical studies at a referral medical center in well-characterized NAFLD patients (n = 58) and healthy controls (n = 27). In addition we performed experimental in vitro studies in hepatocytes. Main Outcome Measures: We examined 1) the hepatic and systemic expression of NAMPT/visfatin in patients with NAFLD and control subjects, 2) the hepatic regulation of NAMPT/visfatin, and 3) the effect of NAMPT/visfatin on hepatocyte apoptosis. Results: Our main findings were as follows. 1) Patients with NAFLD had decreased NAMPT/visfatin expression both systemically in serum and within the hepatic tissue, with no difference between simple steatosis and nonalcoholic steatohepatitis. 2) By studying the hepatic regulation of NAMPT/visfatin in wild-type and peroxisome proliferators-activated receptor (PPAR)α−/− mice as well as in hepatocytes, we showed that PPARα activation and glucose may be involved in the down-regulation of hepatic NAMPT/visfatin expression in NAFLD. 4) Within the liver, NAMPT/visfatin was located to hepatocytes, and our in vitro studies showed that NAMPT/visfatin exerts antiapoptotic effects in these cells, involving enzymatic synthesis of nicotinamide adenine dinucleotide. Conclusion: Based on these findings, we suggest a role for decreased NAMPT/visfatin levels in hepatocyte apoptosis in NAFLD-related disease.
Type of Medium:
Online Resource
ISSN:
0021-972X
,
1945-7197
DOI:
10.1210/jc.2009-2148
Language:
English
Publisher:
The Endocrine Society
Publication Date:
2010
detail.hit.zdb_id:
2026217-6
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