title: Neonatal hyper- and hypothyroidism alter the myoglobin gene expression program in adulthood.
abstract: Myoglobin acts as an oxygen store and a reactive oxygen species acceptor in muscles. We examined myoglobin mRNA in rat cardiac ventricle and skeletal muscles during the first 42 days of life and the impact of transient neonatal hypo- and hyperthyroidism on the myoglobin gene expression pattern. Cardiac ventricle and skeletal muscles of Wistar rats at 7-42 days of life were quickly removed, and myoglobin mRNA was determined by Northern blot analysis. Rats were treated with propylthiouracil (5-10 mg/100 g) and triiodothyronine (0.5-50 µg/100 g) for 5, 15, or 30 days after birth to induce hypo- and hyperthyroidism and euthanized either just after treatment or at 90 days. During postnatal (P) days 7-28, the ventricle myoglobin mRNA remained unchanged, but it gradually increased in skeletal muscle (12-fold). Triiodothyronine treatment, from days P0-P5, increased the skeletal muscle myoglobin mRNA 1.5- to 4.5-fold; a 2.5-fold increase was observed in ventricle muscle, but only when triiodothyronine treatment was extended to day P15. Conversely, hypothyroidism at P5 markedly decreased (60%) ventricular myoglobin mRNA. Moreover, transient hyperthyroidism in the neonatal period increased ventricle myoglobin mRNA (2-fold), and decreased heart rate (5%), fast muscle myoglobin mRNA (30%) and body weight (20%) in adulthood. Transient hypothyroidism in the neonatal period also permanently decreased fast muscle myoglobin mRNA (30%) and body weight (14%). These results indicated that changes in triiodothyronine supply in the neonatal period alter the myoglobin expression program in ventricle and skeletal muscle, leading to specific physiological repercussions and alterations in other parameters in adulthood.
authors.affiliation: Faculdade de Ciências Biológicas e Ambientais, Universidade Federal da Grande Dourados, Dourados, MS, Brasil.
authors.forename: K de Picoli
authors.initials: Kde P
authors.lastname: Souza
authors.affiliation: Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil.
authors.forename: M T
authors.initials: MT
authors.lastname: Nunes
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D013956:Antithyroid Agents; D001794:Blood Pressure; D015152:Blotting, Northern; D015870:Gene Expression; D006339:Heart Rate; D006352:Heart Ventricles / Q000378:metabolism; D006980:Hyperthyroidism / Q000139:chemically induced / Q000378:metabolism*; D007037:Hypothyroidism / Q000139:chemically induced / Q000378:metabolism*; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D009211:Myoglobin / Q000235:genetics* / Q000378:metabolism; D009929:Organ Size; D011441:Propylthiouracil; D012333:RNA, Messenger / Q000378:metabolism*; D011897:Random Allocation; D017208:Rats, Wistar; D017382:Reactive Oxygen Species; D014284:Triiodothyronine
chemical_list: D013956:Antithyroid Agents; D009211:Myoglobin; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D014284:Triiodothyronine; D011441:Propylthiouracil
references.citation: J Exp Biol. 2003 Jun;206(Pt 12):2011-20
references.pmid: 12756283
references.citation: Am J Physiol. 1994 Apr;266(4 Pt 1):E548-59
references.pmid: 8178975
references.citation: Fetal Diagn Ther. 2000 Mar-Apr;15(2):122-6
references.pmid: 10720879
references.citation: Am J Physiol Endocrinol Metab. 2011 Nov;301(5):E818-24
references.pmid: 21771965
references.citation: J Biol Chem. 2001 Jun 22;276(25):22892-900
references.pmid: 11303022
references.citation: Thyroid. 2001 Jun;11(6):545-50
references.pmid: 11442001
references.citation: Clin Perinatol. 1988 Sep;15(3):421-46
references.pmid: 2975979
references.citation: Acta Endocrinol (Copenh). 1976 Dec;83(4):752-62
references.pmid: 1036648
references.citation: Mol Cell Biol. 2005 Aug;25(15):6629-38
references.pmid: 16024798
references.citation: Basic Res Cardiol. 1990 May-Jun;85(3):237-46
references.pmid: 2166497
references.citation: Am J Physiol. 1999 Apr;276(4 Pt 2):R954-61
references.pmid: 10198372
references.citation: Am J Physiol. 1998 Jul;275(1):H264-73
references.pmid: 9688923
references.citation: Acta Histochem. 2004;106(2):145-54
references.pmid: 15147636
references.citation: Cardiovasc Res. 1998 Feb;37(2):405-23
references.pmid: 9614496
references.citation: Biochim Biophys Acta. 1983 May 25;757(2):182-90
references.pmid: 6342682
references.citation: Circ Res. 2001 Apr 13;88(7):713-20
references.pmid: 11304494
references.citation: Biosci Rep. 2005 Jun-Aug;25(3-4):251-69
references.pmid: 16283556
references.citation: J Mol Endocrinol. 1999 Oct;23(2):241-54
references.pmid: 10514561
references.citation: Dev Genet. 1996;19(2):146-56
references.pmid: 8900047
references.citation: Can J Physiol Pharmacol. 1985 Apr;63(4):279-82
references.pmid: 4005702
references.citation: Pflugers Arch. 2006 Apr;452(1):36-42
references.pmid: 16468052
references.citation: Mol Cell Endocrinol. 1992 Dec;90(1):125-31
references.pmid: 1301393
references.citation: Endocrinology. 1983 Jun;112(6):2081-7
references.pmid: 6221921
references.citation: Mol Cell Endocrinol. 2004 Oct 29;226(1-2):19-26
references.pmid: 15489001
references.citation: Mol Endocrinol. 2003 Aug;17(8):1508-21
references.pmid: 12775767
references.citation: Circ Res. 2005 Apr 29;96(8):e68-75
references.pmid: 15817884
references.citation: Mol Cell Endocrinol. 2007 Jan 29;264(1-2):109-17
references.pmid: 17118529
references.citation: Endocrinology. 1993 Dec;133(6):2604-9
references.pmid: 8243283
references.citation: J Appl Physiol (1985). 2013 Feb 15;114(4):490-7
references.pmid: 23195625
references.citation: Mol Phylogenet Evol. 2013 Feb;66(2):469-78
references.pmid: 22846683
references.citation: J Endocrinol. 2006 Aug;190(2):407-14
references.pmid: 16899573
references.citation: Dev Biol. 2004 Aug 1;272(1):104-17
references.pmid: 15242794
references.citation: Am J Physiol Regul Integr Comp Physiol. 2004 Apr;286(4):R786-92
references.pmid: 14656764
references.citation: Endocrinology. 1990 Apr;126(4):1950-8
references.pmid: 2318152
references.citation: Toxicol Sci. 1999 Sep;51(1):54-70
references.pmid: 10496677
references.citation: J Biol Chem. 1994 Feb 25;269(8):5905-12
references.pmid: 8119934
references.citation: Endocrinology. 1992 Feb;130(2):837-46
references.pmid: 1370797