Contents lists available at BioMedSciDirect Publications Journal homepage: www.biomedscidirect.com International Journal of Biological & Medical Research Int J Biol Med Res. 2011; 2(3): 803-805 Elevated Plasma Leptin Levels in Autistic Children of Sultanate of Oman a,b,c, * b d d a a d b Essa MM , Braidy N , Al-Sharbati MM , Al-Farsi YM , Ali A , Waly MI , Al-Shaffae MA , Gilles GJ A R T I C L E I N F O ABSTRACT Keywords: Short Report Leptin Inflammation Cytokine like hormone Autism Oman 1. Introduction Autistic spectrum disorders (ASD) are mysterious, complex, childhood pervasive developmental disorders characterized by impairments in social interaction, deficits in verbal and non-verbal communication, and restricted repetitive and stereotyped patterns of behavior and interests. The etiology of this disorder is poorly understood and no biomarkers have yet been identified as characteristic of ASD. Leptin, a peptide hormone mainly secreted by adipose tissue, is involved in the regulation of body weight and energy expenditure. Leptin also play a role in regulation of neuroendocrine functions, immune system and inflammatory response and development. Recent evidences suggest that leptin might be implicated in the pathophysiology of autism. Availability of biochemical data related with leptin for Omani autistic children is scarce. So, the current study was aimed to compare the levels of leptin in the plasma of ASD children in Sultanate of Oman. Significant higher levels of leptin were found in Omani autistic children as compared with controls. Our results corroborate with the previous findings and also suggest that there might be some relationship between leptin and the pathophysiology of autism. The exact mechanism is still unknown and further extensive research needed. Autistic spectrum disorders (ASD) are mysterious, complex, childhood pervasive developmental disorders characterized by impairments in social interaction, deficits in verbal and non-verbal communication, and restricted repetitive and stereotyped patterns of behavior and interests [1]. Studies suggest that there might be involvement of genetic factors [2] and the etiology of this disorder is poorly understood and no biomarkers have yet been identified as characteristic of ASD. Although the precise mechanism underlying the pathophysiology of autism remains to be determined, accumulating evidence suggests that a combination of environmental or perhaps in utero risk factors, autoimmune risk factors and abnormality of inflammatory events along with localized inflammation of the central nervous system may contribute to the pathogenesis of ASD [3-13]. Despite numerous reports suggesting a high rate of inheritance, no specific single genes have been identified that are more than risk factors [14-15]. The identification of specific biochemical correlates of autism might increase the reliability of the behavioral diagnosis of this disorder. Sultanate of Oman is a developing Arab country located in the South Eastern of the Arabian Peninsula and the total population is approximately 3.5 million, about half of which is below the age of 15 years [16]. 113 diagnosed cases of ASD were reported nationwide and the prevalence of ASD in Oman was reported low (1.4 cases per 10,000 children aged 0–14 years) compared to western countries, which is attributed to under-diagnosis and under-reporting. More prevalent cases were among boys (75%) and among low-income families in Oman also reported [17]. Leptin, a peptide hormone mainly secreted by adipose tissue, is involved in the regulation of body weight and energy expenditure at the hypothalamic level [13]. Serum leptin concentrations are related to fat tissue and body mass index (BMI) in children and adults [18-20]. It has become increasingly evident that leptin may BioMedSciDirect Publications Copyright 2010 BioMedSciDirect Publications IJBMR - All rights reserved. ISSN: 0976:6685. c International Journal of BIOLOGICAL AND MEDICAL RESEARCH www.biomedscidirect.com Int J Biol Med Res Volume 2, Issue 3, July 2011 a Dept of Food Science and Nutrition, College of Agriculture and Marine Sciences, Sultan Qaboos University, Oman b Neuropharmacology group, Dept of Pharmacology, College of Medicine, University of New South Wales, Sydney, Australia c Developmental Neuroscience Lab, NYSIBR, 1050 Forest Hill road, Staten Island, NY, 10314, USA d College of Medicine and Health Sciences, Sultan Qaboos University, Oman * Corresponding Author : Dr. M. Mohamed Essa Assistant Professor Dept. of Food Sciences and Human Nutrition CAMS, Sultan Qaboos University, P.O No: 34, Al-Khoud, Muscat, Postal Code: 123, Sultanate of Oman Phone: 00968 2414 3604 Email: drmdessa@gmail.com Copyright 2010 BioMedSciDirect Publications. All rights reserved. c