The prevalence of obesity is rising around the world and prospective studies show that in 2025, Brazil will be the fifth country in the world to have obesity problems. Multifactorial factors are involved in the genesis of obesity including genetic, psychological, metabolic and environmental factors. Recently, adipocytes have been considered an endocrine tissue capable of producing several substances, including adiponectin, angiotensin and leptin. Leptin is the main peptide produced by adipocytes and its serum concentration represents an important peripheral signal in the regulation of food intake and energy expenditure. In addition to leptin, a new peptide called ghrelin has been recently discovered. Ghrelin, a gastrointestinal peptide hormone identified in the stomach, is directly involved with short-term regulation of energy balance. Thus, this review will focus on the role of both leptin and ghrelin in controlling body weight and the ongoing limitations in treating obesity in human beings.
hypothalamus; leptin; metabolism; obesity; adipose tissue
