title: Enhanced neuronal loss under perinatal hypothyroidism involves impaired neurotrophic signaling and increased proteolysis of p75(NTR).
abstract: Recognition of the molecular events that lead to enhanced cell death is vital to understand the developmental cerebellar defects under hypothyroidism. Though neurotrophins promote the survival and development of neurons in the cerebellum, but the mechanism of their insufficiency mediated cell loss under hypothyroidism is unknown. Here in developmental hypothyroid rat model we report that hypothyroidism induced neuronal loss involve down regulation of neurotrophic survival signaling and increased truncation of the receptor p75(NTR). Results showed that perinatal hypothyroidism besides repressing the expression of BDNF also impairs the maturation of NGF which results in decreased activation of ERK, CREB, NF-kappaB and AKT. Furthermore hypothyroidism caused an enhanced expression and proteolysis of p75(NTR). The increased proteolysis of p75(NTR)in vivo and its association with death of granule neurons brings forward hitherto a p75(NTR) dependence signaling which along with compromised survival signaling could provide a neurotrophic basis of understanding the cause of enhanced cell death in developing cerebellum under hypothyroidism.
authors.affiliation: Department of Endocrinology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Rohit Anthony
authors.initials: RA
authors.lastname: Sinha
authors.forename: Amrita
authors.initials: A
authors.lastname: Pathak
authors.forename: Ashok
authors.initials: A
authors.lastname: Kumar
authors.forename: Meenakshi
authors.initials: M
authors.lastname: Tiwari
authors.forename: Ashutosh
authors.initials: A
authors.lastname: Shrivastava
authors.forename: Madan M
authors.initials: MM
authors.lastname: Godbole
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D002470:Cell Survival; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology; D005260:Female; D007037:Hypothyroidism / Q000378:metabolism*; D009414:Nerve Growth Factors / Q000235:genetics / Q000378:metabolism*; D009419:Nerve Tissue Proteins; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D053218:Receptors, Death Domain / Q000378:metabolism; D017978:Receptors, Growth Factor; D017475:Receptors, Nerve Growth Factor / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D013963:Thyroid Hormones / Q000008:administration & dosage / Q000097:blood
chemical_list: D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D053218:Receptors, Death Domain; D017978:Receptors, Growth Factor; D017475:Receptors, Nerve Growth Factor; D013963:Thyroid Hormones; C068313:Ngfr protein, rat