Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The onset of feeding at birth is a vital step for the adaptation of the neonate to extra uterine life. Prader-Willi syndrome (PWS) is a complex neurogenetic disorder caused by the alteration of several imprinted contiguous genes including MAGEL2. PWS presents with various clinical manifestations, including poor suckling behaviour and feeding problems in neonates. Hypothalamic defects have been proposed, but the pathophysiological mechanisms remain poorly understood. Here, we report that a Magel2-deficient mouse with 50% neonatal mortality had an altered onset of suckling activity and subsequent impaired feeding, suggesting a role of MAGEL2 in the suckling deficit seen in PW newborns. The hypothalamus of Magel2 mutant neonates showed a significant reduction in oxytocin (OT). Furthermore, injection of a specific OT receptor antagonist in wild-type neonates recapitulated the feeding deficiency seen in Magel2 mutants, and a single injection of OT, 3-5 h after birth, rescued the phenotype of Magel2 mutant pups, allowing all of them to survive. Our study illustrates the crucial role of feeding onset behaviour after birth. We propose that OT supply might constitute a promising avenue for the treatment of feeding difficulties in PW neonates and potentially of other newborns with impaired feeding onset.
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PMID:A single postnatal injection of oxytocin rescues the lethal feeding behaviour in mouse newborns deficient for the imprinted Magel2 gene. 2087 15

MAGED1, NECDIN and MAGEL2 are members of the MAGE gene family. The latter two of these genes have been involved in Prader-Willi syndrome (PWS), which includes hyperphagia, repetitive and compulsive behaviors, and cognitive impairment. Here, we show that Maged1-deficient mice develop progressive obesity associated with hyperphagia and reduced motor activity. Loss of Maged1 also results in a complex behavioral syndrome that includes reduced social interactions and memory, deficient sexual behavior, as well as increased anxiety and self-grooming. Oxytocin (OT), which is produced in the hypothalamus, can act as a neurotransmitter that reduces anxiety, promotes social behaviors and regulates food intake. Growing evidences indicate that OT is involved in autism. We found that Maged1 mutants showed a severe reduction in the levels of mature OT, but not of its precursors, in the hypothalamus. Moreover, the administration of OT rescued the deficit in social memory of these mice. We conclude that Maged1 is required for OT processing or stability. A decrease in mature OT levels in Maged1 mutants affects social interactions and possibly other behavioral processes. Our observations suggest that, in human, MAGED1 could play a role in autism or cause a neurodevelopmental condition that is reminiscent of the PWS.
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PMID:Loss of Maged1 results in obesity, deficits of social interactions, impaired sexual behavior and severe alteration of mature oxytocin production in the hypothalamus. 2286 74

Prader-Willi and the related Schaaf-Yang Syndromes (PWS/SYS) are rare neurodevelopmental disorders characterized by overlapping phenotypes of high incidence of autism spectrum disorders (ASD) and neonatal feeding difficulties. Based on clinical and basic studies, oxytocin pathway defects are suggested to contribute disease pathogenesis but the mechanism has been poorly understood. Specifically, whether the impairment in oxytocin system is limited to neuropeptide levels and how the functional properties of broader oxytocin neuron circuits affected in PWS/SYS have not been addressed. Using cell type specific electrophysiology, we investigated basic synaptic and cell autonomous properties of oxytocin neurons in the absence of MAGEL2; a hypothalamus enriched ubiquitin ligase regulator that is inactivated in both syndromes. We observed significant suppression of overall ex vivo oxytocin neuron activity, which was largely contributed by altered synaptic input profile; with reduced excitatory and increased inhibitory currents. Our results suggest that dysregulation of oxytocin system goes beyond altered neuropeptide expression and synaptic excitation inhibition imbalance impairs overall oxytocin pathway function.
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PMID:Inactivation of Magel2 suppresses oxytocin neurons through synaptic excitation-inhibition imbalance. 3024 Jul 6