Other inflammatory markers and related factors should be kept in mind in metabolic syndrome with psoriasis patients

Abstract

Dear Editor, We have read with great interest the recently published article entitled ‘‘Circulating levels of lipocalin-2 and retinol-binding protein-4 (RBP-4) are increased in psoriatic patients and correlated with baseline Psoriasis Area and Severity Index (PASI)’’ by Jorge Romani and coworkers [8]. In that very well-presented article, they aimed to evaluate profile of a number in different adipokines and cytokines in patients and controls and to evaluate correlation with severity of the skin disease and the changes after narrow-band UVB. They concluded that differences in the adipokine profile between psoriatic patients and controls seem to be independent of joint involvement. Lipocalin-2 and RBP-4, in particular, appeared to be related to severity of the skin disease. Metabolic syndrome (MetS) is a clinical entity comprising risk factors such as hypertension, glucose intolerance, atherogenic lipid profile, abdominal obesity, lack of physical activity, and increased inflammatory state. Most of the recent studies demonstrated that there was a correlation between inflammatory mediators and components of MetS. Particularly, interleukin 6, TNF-a, and C-reactive protein levels were observed to increase in MetS [11]. Adipokines are peptide hormones or cytokines secreted from adipose tissues and involved in the pathogenesis of MetS. Psoriasis patients have a high prevalence of the MetS. Psoriasis as a chronic inflammatory skin disorder is characterized by a variety of immunologic and inflammatory changes and may similarly predispose for those inflammatory disorders. This could likely be due to the effects of chronic inflammatory changes, in particular, the secretion of proinflammatory cytokines [7]. The role of chronic inflammation causing metabolic and vascular disorders is increasingly recognized. It is hypothesized that proinflammatory cytokines contribute to atherogenesis, peripheral insulin resistance, and the development of hypertension and type II diabetes [9]. Psoriasis is associated with an increase of some cytokines. Increased serum cytokines were positively correlated with PASI [6]. The lipocalins have been suggested to mediate obesity-associated insulin resistance and other metabolic comorbidities [10]. Increases in the serum concentration of RBP-4 have been observed in obese adults with type 2 diabetes. Lipocalin-2 belongs to the same protein family as RBP-4 and is a known inflammatory biomarker that is positively correlated with body mass index (BMI) and other variables of the metabolic syndrome [3]. Several circulating cytokines are increased with obesity and may combine with the influence of visceral fat to generate insulin resistance, inflammation, and fibrosis in nonalcoholic fatty liver disease (NAFLD). Little information exists in NAFLD about three recently recognized tissue-derived cytokines that are all lipid-binding and involved in inflammation, namely adipocyte fatty acid-binding protein, lipocalin-2, and RBP-4 [5]. It could be related to the complex mechanistic relation between alcohol consumption and each component of MS. While mild to moderate alcohol consumption has a favorable influence on lipids metabolism, abdominal obesity and glucose regulation, on the other hand, alcohol consumption causes hypertension, and hypertriglyceridemia, constituting alcohol-related metabolic syndrome [1]. In current study, if I. Balta Department of Dermatology, Kecioren Training and Research Hospital, Ankara, Turkey