Is Melatonin the Cornucopia of the 21st Century?

Melatonin, an indoleamine hormone produced and secreted at night by pinealocytes and extra-pineal cells, plays an important role in timing circadian rhythms (24-h internal clock) and regulating the sleep/wake cycle in humans. However, in recent years melatonin has gained much attention mainly because of its demonstrated powerful lipophilic antioxidant and free radical scavenging action. Melatonin has been proven to be twice as active as vitamin E, believed to be the most effective lipophilic antioxidant. Melatonin-induced signal transduction through melatonin receptors promotes the expression of antioxidant enzymes as well as inflammation-related genes. Melatonin also exerts an immunomodulatory action through the stimulation of high-affinity receptors expressed in immunocompetent cells. Here, we reviewed the efficacy, safety and side effects of melatonin supplementation in treating oxidative stress- and/or inflammation-related disorders, such as obesity, cardiovascular diseases, immune disorders, infectious diseases, cancer, neurodegenerative diseases, as well as osteoporosis and infertility.

Dysbiosis and Prematurity: Is There a Role for Probiotics?

Healthy microbiota is a critical mediator in maintaining health and it is supposed that dysbiosis could have a role in the pathogenesis of a number of diseases. Evidence supports the hypothesis that maternal dysbiosis could act as a trigger for preterm birth; aberrant colonization of preterm infant gut might have a role in feeding intolerance and pathogenesis of necrotizing enterocolitis. Despite several clinical trials and meta-analyses, it is still not clear if modulation of maternal and neonatal microbiota with probiotic supplementation decreases the risk of preterm birth and its complications.

Weaning Time in Preterm Infants: An Audit of Italian Primary Care Paediatricians.

INTRODUCTION: According to the 2016 Italian National Institute of Statistics (Istat) data in Italy, about 6.7% of all newborns are born prematurely. Due to the lack of data on current complementary feeding in preterm infants in Italy, the aim of the survey was to evaluate individual attitudes of primary care paediatricians, concerning the introduction of complementary foods in preterm infants. METHODS: An internet-based survey was conducted among primary care paediatricians, working in Italy, regarding (1) timing of the introduction of complementary foods to preterm newborns; (2) type of complementary foods introduced; (3) vitamin D and iron supplementations. RESULTS: A total of 347 primary care Italian paediatricians answered the questionnaire; 44% of responders based the timing of the introduction of solid food exclusively on an infant's age, 18% on an infant's neurodevelopmental status and 4% on the body weight; the remaining 34% based the timing on two or more of these aspects. The type of complementary foods did not comply with an evidence-based sequence; 98% of participants promoted vitamin D supplementation and 89% promoted iron supplementation with great diversity in timing and doses. CONCLUSIONS: Due to limited evidence, there is a great heterogeneity in the attitudes of primary care paediatricians concerning the introduction of complementary foods to preterm newborns. Further research is needed to provide evidence-based guidelines regarding weaning preterm newborns.

Crude venom from nematocysts of Pelagia noctiluca (Cnidaria: Scyphozoa) elicits a sodium conductance in the plasma membrane of mammalian cells.

Cnidarians may negatively impact human activities and public health but concomitantly their venom represents a rich source of bioactive substances. Pelagia noctiluca is the most venomous and abundant jellyfish of the Mediterranean Sea and possesses a venom with hemolytic and cytolytic activity for which the mechanism is largely unknown. Here we show that exposure of mammalian cells to crude venom from the nematocysts of P. noctiluca profoundly alters the ion conductance of the plasma membrane, therefore affecting homeostatic functions such as the regulation and maintenance of cellular volume. Venom-treated cells exhibited a large, inwardly rectifying current mainly due to permeation of Na+ and Cl-, sensitive to amiloride and completely abrogated following harsh thermal treatment of crude venom extract. Curiously, the plasma membrane conductance of Ca2+ and K+ was not affected. Current-inducing activity was also observed following delivery of venom to the cytosolic side of the plasma membrane, consistent with a pore-forming mechanism. Venom-induced NaCl influx followed by water and consequent cell swelling most likely underlie the hemolytic and cytolytic activity of P. noctiluca venom. The present study underscores unique properties of P. noctiluca venom and provides essential information for a possible use of its active compounds and treatment of envenomation.