Neurons have a highly asymmetric shape and they are constituted by two functional domains: the axonal, and the somatodendritic domains. Axons are cellular processes that make contact with target cells to transmit information, while dendrites located in the somatodendritic domain are specialized in the reception of information. During neurodevelopment, neurons acquire the highly morphofunctional polarization through a dynamic cytoskeletal organization. Melatonin, the main indolamine secreted by the pineal gland has two important properties which play a key role in the maintaining of neuron polarization: it is a potent free radical scavenger, and it is a cytoskeletal modulator. Melatonin stimulates cytoskeletal polarization through PKC and ROCK activation by recruiting cells at early stages of neurodevelopment for later differentiation. At later stages, melatonin induces neurite and microtubule enlargement by a calmodulin antagonism. Moreover, melatonin prevents the asymmetric shape lost induced by oxidative stress, a condition present in neuropsychiatric diseases, and abolishes the cytoskeletal damage caused by prolonged treatment with antipsychotics, restoring the morphofunctional polarization. Moreover, in organotypic cultures, melatonin at nanomolar concentrations enhances the number of dendrites and their complexity in hilar neurons of the hippocampus. In addition, melatonin stimulates the formation of new neurons in vitro and in a rodent model. In this review we will describe current evidences indicative of the melatonin participation in the neuronal morphofunctional differentiation as a cytoskeletal modulator. Also we will discuss the implications of the loss of neuronal polarization in neuropsychiatric diseases and the potential therapeutic utility of melatonin for the treatment of these illnesses.
"Open access will revolutionize 21st century knowledge work and accelerate the diffusion of ideas and evidence that support just in time learning and the evolution of thinking in a number of disciplines."
"It is important that students and researchers from all over the world can have easy access to relevant, high-standard and timely scientific information. This is exactly what Open Access Journals provide and this is the reason why I support this endeavor."
"Publishing research articles is the key for future scientific progress. Open Access publishing is therefore of utmost importance for wider dissemination of information, and will help serving the best interest of the scientific community."
"Open access journals are a novel concept in the medical literature. They offer accessible information to a wide variety of individuals, including physicians, medical students, clinical investigators, and the general public. They are an outstanding source of medical and scientific information."
"Open access journals are extremely useful for graduate students, investigators and all other interested persons to read important scientific articles and subscribe scientific journals. Indeed, the research articles span a wide range of area and of high quality. This is specially a must for researchers belonging to institutions with limited library facility and funding to subscribe scientific journals."
"Open access journals represent a major break-through in publishing. They provide easy access to the latest research on a wide variety of issues. Relevant and timely articles are made available in a fraction of the time taken by more conventional publishers. Articles are of uniformly high quality and written by the world's leading authorities."
"Open access journals have transformed the way scientific data is published and disseminated: particularly, whilst ensuring a high quality standard and transparency in the editorial process, they have increased the access to the scientific literature by those researchers that have limited library support or that are working on small budgets."
"Not only do open access journals greatly improve the access to high quality information for scientists in the developing world, it also provides extra exposure for our papers."
"Open Access 'Chemistry' Journals allow the dissemination of knowledge at your finger tips without paying for the scientific content."
"In principle, all scientific journals should have open access, as should be science itself. Open access journals are very helpful for students, researchers and the general public including people from institutions which do not have library or cannot afford to subscribe scientific journals. The articles are high standard and cover a wide area."
"The widest possible diffusion of information is critical for the advancement of science. In this perspective, open access journals are instrumental in fostering researches and achievements."
"Open access journals are very useful for all scientists as they can have quick information in the different fields of science."
"There are many scientists who can not afford the rather expensive subscriptions to scientific journals. Open access journals offer a good alternative for free access to good quality scientific information."
"Open access journals have become a fundamental tool for students, researchers, patients and the general public. Many people from institutions which do not have library or cannot afford to subscribe scientific journals benefit of them on a daily basis. The articles are among the best and cover most scientific areas."
"These journals provide researchers with a platform for rapid, open access scientific communication. The articles are of high quality and broad scope."
"Open access journals are probably one of the most important contributions to promote and diffuse science worldwide."
"Open access journals make up a new and rather revolutionary way to scientific publication. This option opens several quite interesting possibilities to disseminate openly and freely new knowledge and even to facilitate interpersonal communication among scientists."
"Open access journals are freely available online throughout the world, for you to read, download, copy, distribute, and use. The articles published in the open access journals are high quality and cover a wide range of fields."
"Open Access journals offer an innovative and efficient way of publication for academics and professionals in a wide range of disciplines. The papers published are of high quality after rigorous peer review and they are Indexed in: major international databases. I read Open Access journals to keep abreast of the recent development in my field of study."
"It is a modern trend for publishers to establish open access journals. Researchers, faculty members, and students will be greatly benefited by the new journals of Bentham Science Publishers Ltd. in this category."