Serotonin/growth hormone/insulin-like growth factors axis on pre- and post-natal development: A contemporary review

Introduction l-tryptophan is the precursor of serotonin. Serotonin regulates the secretion of pituitary growth hormonewhich in turn stimulates production of insulin-like growth factors (IGFs). IGFs are necessary for development and growth. We reviewed the most recent literature regarding the role of serotonin/growth hormone/IGF-I axis on development and growth. The link between serotonin, growth hormone and IGF production is widely reported in the literature. Many studies demonstrate impaired growth and development in off spring of pregnant rats with low levels of plasmatic serotonin. The most recent literature shows the possible negative influ ence of serotonin in excess on differentiation of serotonergic neurons with consequent reduction in pituitary growth hormone production, which has a direct effect on hepatic production of IGF-I, particularly in the post-natal period. Recent literature also shows that hyperserotonemia in pregnant rats causes disorders in offspring, such as lower body mass and a lower survival rate. In addition, data show that high serotonin levels could inhibit development of serotonin neurons and lead to anatomic and functional alter ations of the brain. Also, a recent study by us supports the negative effects of hyperserotonemiaon pre- and post natal development. In this paper, we considered the influence of different growth factors and hormones on pre- and post-natal development. Conclusion Pre- and post-natal development depends on genetic, environmental factors and several growth factors. The ability of the placenta to provide the foetus for all molecular components is fundamental to allow a normal development and growth. This paper expresses brief considerations on some aspects of pre- and post-natal development. It gives a synthetic overview on the role of serotonin/ growth hormone/IGF-I axis on development and growth.