Evaluation of Adenovirus-36 (Ad-36) antibody seropositivity and adipokine levels in obese children Bekir Kocazeybek Professor a, * , Harika Oyku Dinc a , Sevgi Ergin a , Suat Saribas a , Bahar Taskın Ozcabi b , Utku Cizmecigil c , Eda Altan c , Kevser Atalik d , Pelin Yüksel a , Zeynep Taner a , Asiye Karakullukcu a , Serhat Sirekbasan a , Nuri Turan c , Penbe Cagatay e , Nergiz Imamova a , Olcay Evliyaoglu b , Huseyin Yilmaz c a Istanbul University, Cerrahpasa Medical Faculty, Department of Medical Microbiology, Istanbul, Turkey b Istanbul University, Cerrahpasa Medical Faculty, Department of Child Health and Diseases, Istanbul, Turkey c Istanbul University, Veterinary Faculty, Department of Virology, Avcilar, Istanbul, Turkey d Istanbul University, Istanbul Medical Faculty, Department of Medical Microbiology, Istanbul, Turkey e Istanbul University, Cerrahpasa Medical Faculty, Vocational School of Health Services, Istanbul, Turkey article info Article history: Received 18 January 2016 Received in revised form 23 April 2017 Accepted 24 April 2017 Available online 25 April 2017 abstract Adenovirus 36 (Ad-36) has recently been suggested as a possible contributor to the current obesity epidemic. The aim of this study was to investigate the prevalence of Ad-36 antibodies in obese children, as well as investigate the role of serum leptin and lipid levels in Ad-36-obesity. Seventy-one obese children and 62 non-obese children were included as the patient group (PG), including the healthy control group (HCG), respectively. Simultaneously, Ad-36 antibodies and adipokine levels were assessed with serum neutralization assays (SNA) and ELISA. Ad-36 antibody was detected in 9 patients (12.7%) and 1 patient (1.6%) in both the PG and HCG, respectively, while a significant difference was detected between groups (p < 0.05). Although serum LDL, total cholesterol, triglycerides and leptin levels were detected significantly higher, adiponectin level was detected paradoxically lower in the PG. However, a significant difference was not detected for lipids and leptin levels; adiponectin levels were found to be significantly lower in Ad-36 antibody-positive PG (p < 0.05). In conclusion, we suggest there is an association between Ad-36 and obesity in children, including IL-6 levels increasing in obese children with Ad-36 seropositivity. Conversely, adiponectin levels in obese children with Ad-36 seropositivity were higher. As such, there is a need for studies to understand the mechanisms underlying this observation. © 2017 Elsevier Ltd. All rights reserved. 1. Introduction Recently, obesity is considered as one of the major public health problems to become a worldwide epidemic. Obesity also increases the risk of hypertension, coronary heart disease, stroke, and some cancers that cause serious morbidity and mortality. Additionally, obesity is also considered to be a state of low-grade chronic inflammation [1,2]. The prevalence of obesity in children and adults have also rapidly increased in Turkey [3]. Although energy intake of foods exceeds energy expenditure, and excess energy accumulates in adipose tissue as fat, it is accepted as the fundamental cause of obesity. Recently, infectious agents have been considered as po- tential etiological agents in the progression of obesity and the term “infectobesity”, which has similarly been suggested [4,5]. Human adenovirus-36 (Ad-36), first isolated in Germany in 1978 from the feces of a girl with enteritis and diabetes mellitus, is the first human virus linked with obesity in both animals and humans [6]. Ad-36-induced adiposity in a chicken model was reported by Dhurandhar et al. [7] for the first time. In the following experi- mental animal model studies, it was shown that Ad-36 can lead to obesity progression by causing hyperplasia and hypertrophy in the adipocytes of mice, rats, and monkeys [5,7,8]. In addition, sero- logical and molecular studies, including children and adults, * Corresponding author. Istanbul University, Cerrahpasa Faculty of Medicine, Department of Medical Microbiology, Cerrahpasa Street, 34098 Istanbul, Turkey. E-mail address: bzeybek@istanbul.edu.tr (B. Kocazeybek). Contents lists available at ScienceDirect Microbial Pathogenesis journal homepage: www.elsevier.com/locate/micpath http://dx.doi.org/10.1016/j.micpath.2017.04.034 0882-4010/© 2017 Elsevier Ltd. All rights reserved. Microbial Pathogenesis 108 (2017) 27e31