The potential role of the novel hypothalamic neuropeptides nesfatin-1, phoenixin, spexin and kisspeptin in the pathogenesis of anxiety and anorexia nervosa

Due to the dynamic development of molecular neurobiology and bioinformatic methods several novel brain neuropeptides have been identified and characterized in recent years. Contemporary techniques of selective molecular detection e.g. in situ Real-Time PCR, microdiffusion and some bioinformatics strategies that base on searching for single structural features common to diverse neuropeptides such as hidden Markov model (HMM) have been successfully introduced. A convincing majority of neuropeptides have unique properties as well as a broad spectrum of physiological activity in numerous neuronal pathways including the hypothalamus and limbic system. The newly discovered but uncharacterized regulatory factors nesfatin-1, phoenixin, spexin and kisspeptin have the potential to be unique modulators of stress responses and eating behaviour. Accumulating basic studies revelaed an intriguing role of these neuropeptides in the brain pathways involved in the pathogenesis of anxiety behaviour. Nesfatin-1, phoenixin, spexin and kisspeptin may also distinctly affect the energy homeostasis and modulate food intake not only at the level of hypothalamic centres. Moreover, in patients suffered from anxiety and anorexia nervosa a significant, sex-related changes in the plasma neuropeptide levels occurred. It should be therefore taken into account that the targeted pharmacomodulation of central peptidergic signaling may be potentially helpful in the future treatment of certain neuropsychiatric and metabolic disorders. This article reviews recent evidence dealing with the hypothetical role of these new factors in the anxiety-related circuits and pathophysiology of anorexia nervosa.