516 European Journal of Clinical Investigation Vol 38 DOI: 10.1111/j.1365-2362.2008.01964.x Blackwell Publishing Ltd ORIGINAL ARTICLES Visfatin expression in relation to BMI and hormones Visfatin expression in relation to BMI and hormones M. Kovacikova et al. ORIGINAL ARTICLE Visfatin expression in subcutaneous adipose tissue of pre-menopausal women: relation to hormones and weight reduction M. Kovacikova * , M. Vitkova *,† , E. Klimcakova *,†,‡ , J. Polak * , J. Hejnova * , M. Bajzova * , Z. Kovacova * , N. Viguerie *,†,‡ , D. Langin *,†,‡ and V. Stich * * Charles University, Prague, Czech Republic, † Toulouse, France, ‡ Paul Sabatier University, France ABSTRACT Background A novel adipokine, visfatin, was found to be related to adiposity in humans and regulated by a number of hormonal signals. The aim of this study was to investigate the relationships of visfatin expression in adipose tissue with potential regulatory factors such as insulin, testosterone and tumor necrosis factor-α (TNF-α) and to elucidate the effect of a diet induced weight reduction on adipose tissue mRNA expression and plasma levels of visfatin. Materials and methods Biopsies of subcutaneous abdominal adipose tissue (SCAAT) and plasma samples were obtained at the beginning of the study from 47 pre-menopausal women (age 38·7 ± 1·7 years, body mass index (BMI) 27·9 ± 1·4 kg m –2 ), consisting of 15 lean, 16 overweight and 16 obese subjects. The subgroup of 32 overweight/obese women (age 42·1 ± 1·9 years, BMI 31·2 ± 0·9 kg m –2 ) underwent a 12 week hypocaloric weight reducing diet and samples were obtained at the end of the diet. Biopsy samples were analysed for visfatin and TNF-α mRNA levels and plasma was analysed for relevant metabolites and hormones. Results In the group of 47 subjects visfatin mRNA expression in SCAAT was negatively correlated with plasma free testosterone (r = –0. 363, P < 0·05) and BMI (r = –0·558, P < 0·01) and positively associated with adipose tissue TNF-α mRNA expression (r = 0·688, P < 0·01). The diet resulted in the reduction of body weight and in the decrease of plasma insulin, free testosterone and TNF-α levels. In the group of overweight/obese subjects visfatin mRNA in SCAAT increased after the diet and the diet induced increase was positively correlated with the magnitude of body weight loss. Conclusion Visfatin mRNA expression in SCAAT is associated with TNF-α expression, plasma free testosterone and BMI in pre-menopausal women. A weight reducing hypocaloric diet results in the increase of visfatin mRNA in SCAAT. Keywords Adipose tissue, mRNA expression, obesity, TNF-α, visfatin, weight reduction. Eur J Clin Invest 2008; 38 (7): 516–522 Introduction Visfatin, a novel adipokine, previously known as pre-B-cell colony-enhancing factor (PBEF), has been suggested to play a role in the regulation of glucose homeostasis [1–3]. In the original study of Fukuhara [1] that was recently withdrawn, visfatin was suggested to exert insulin mimetic effects in various insulin sensitive tissues such as liver, muscle, and fat. These results were not confirmed in a recent study [3]. However, the findings of the latter study suggest a role for visfatin in the regulation of glucose stimulated insulin secretion in pancreatic islets. As a result of previous studies, it has been suggested that visfatin may modify insulin sensitivity and speculations about the possible use of visfatin in the treatment of insulin resistance have been raised. In humans, plasma visfatin has been reported to be higher in obese subjects compared to lean subjects [4–7]. However, the relationship between body mass index (BMI) and plasma visfatin is not straightforward, as the association between obesity and elevated plasma visfatin levels has not been confirmed by other studies [8,9]. Studies by Haider et al. [7] and Manco et al. [10] revealed a reduction of plasma visfatin concentrations after weight loss in morbidly obese patients. Although visfatin has been believed