Effects of weight loss induced by bariatric surgery on hepatic adipocytokine expression

• Published in: Journal of hepatology 2009-10, Vol.51 (4), p.765-777
• Main Authors: Moschen, Alexander R, Molnar, Clemens, Wolf, Anna Maria, Weiss, Helmut, Graziadei, Ivo, Kaser, Susanne, Ebenbichler, Christoph F, Stadlmann, Sylvia, Moser, Patrizia L, Tilg, Herbert
• Format: Article
• Language: English
• Subjects: Adipocytokine; Adipokines - blood; Adipokines - genetics; Adipokines - metabolism; Adiponectin - blood; Adiponectin - genetics; Adiponectin - metabolism; Adult; Bariatric Surgery; Base Sequence; Biological and medical sciences; Cytokines - blood; Cytokines - genetics; Cytokines - metabolism; DNA Primers - genetics; Fatty Liver - genetics; Fatty Liver - metabolism; Fatty Liver - surgery; Female; Gastroenterology and Hepatology; Gastroenterology. Liver. Pancreas. Abdomen; Gastroplasty; Gene Expression; Humans; Leptin - blood; Leptin - genetics; Leptin - metabolism; Liver - metabolism; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Male; Medical sciences; Middle Aged; NAFLD; NASH; Nicotinamide Phosphoribosyltransferase - blood; Nicotinamide Phosphoribosyltransferase - genetics; Nicotinamide Phosphoribosyltransferase - metabolism; Obesity, Morbid - genetics; Obesity, Morbid - metabolism; Obesity, Morbid - pathology; Obesity, Morbid - surgery; Other diseases. Semiology; Prospective Studies; Resistin - blood; Resistin - genetics; Resistin - metabolism; RNA, Messenger - genetics; RNA, Messenger - metabolism; Stomach, duodenum, intestine, rectum, anus; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the digestive system; Weight loss; Weight Loss - genetics; Weight Loss - physiology
• ISSN: 0168-8278; 1600-0641
• DOI: 10.1016/j.jhep.2009.06.016

Background/Aims Adipocytokines play a key role in the pathophysiology of non-alcoholic fatty liver diseases (NAFLD). Whereas adiponectin has mainly anti-inflammatory functions, leptin, resistin and pre-B cell enhancing factor (PBEF)/Nampt/visfatin are considered as mainly pro-inflammatory mediators regulating metabolic and immune processes. Methods We prospectively examined the effect of weight loss on systemic levels and/or hepatic expression of adiponectin/adiponectin receptors, leptin/leptin receptors, resistin and PBEF/Nampt/visfatin. Severely obese patients underwent laparoscopic adjustable gastric banding (LABG) and serum samples ( n = 30) were collected before, and after 6 and 12 months. Paired liver biopsies (before and 6 months after LABG) were obtained from 18 patients. Results Bariatric surgery improved insulin resistance, abnormal liver function tests and liver histology. Pronounced weight loss after 6 and 12 months was accompanied by a significant increase in serum adiponectin levels whereas both leptin and PBEF/Nampt/visfatin levels decreased. Resistin serum levels increased after 6 months but fell below baseline values after 12 months. Liver mRNA expression of adiponectin increased slightly after 6 months whereas leptin mRNA expression did not change. Interestingly, weight loss resulted in a significant decrease of hepatic mRNA expression of resistin, PBEF/Nampt/visfatin and both leptin receptor isoforms while expression of type 1 and 2 adiponectin receptor was not affected. Liver immunohistochemistry performed on index and follow-up liver biopsies revealed an increase in adiponectin staining, showed no effect on resistin/leptin positivity, and demonstrated a decrease in PBEF/Nampt/visfatin immunoreactivity. Conclusions Weight loss after LABG surgery drives the adipocytokine milieu towards a more anti-inflammatory direction both systemically and in the liver.