title: The in vitro maintenance of clock genes expression within the rat pineal gland under standard and norepinephrine-synchronized stimulation.
abstract: Although the norepinephrine (NE) synchronization protocol was proved to be an important procedure for further modulating in vitro pineal melatonin synthesis, the maintenance of clock genes under the same conditions remained to be investigated. The aim of this study was to investigate the maintenance of the clock genes expression in pineal gland cultures under standard and NE-synchronized stimulation. The glands were separated into three experimental groups: Control, Standard (acute NE-stimulation), and NE-synchronized. The expression of Bmal1, Per2, Cry2, Rev-erbα, the clock controlled gene Dbp and Arylalkylamine-N-acetyltransferase were investigated, as well as melatonin content. No oscillations were observed in the expression of the investigated genes from the control group. Under Standard NE stimulation, the clock genes did not exhibit a rhythmic pattern of expression. However, in the NE-synchronized condition, a rhythmic expression pattern was observed in all cases. An enhancement in pineal gland responsiveness to NE stimulation, reflected in an advanced synthesis of melatonin was also observed. Our results reinforce our previous hypothesis that NE synchronization of pineal gland culture mimics the natural rhythmic release of NE in the gland, increasing melatonin synthesis and keeping the pineal circadian clock synchronized, ensuring the fine adjustments that are relied in the clockwork machinery.
authors.affiliation: University of São Paulo, Institute of Biomedical Sciences, Department of Physiology and Biophysics, Av. Prof. Lineu Prestes, 1524, Room 118, São Paulo, SP 05508-900, Brazil.
authors.forename: Jéssica
authors.initials: J
authors.lastname: Andrade-Silva
authors.affiliation: University of São Paulo, Institute of Biomedical Sciences, Department of Physiology and Biophysics, Av. Prof. Lineu Prestes, 1524, Room 118, São Paulo, SP 05508-900, Brazil.
authors.forename: José
authors.initials: J
authors.lastname: Cipolla-Neto
authors.affiliation: University of São Paulo, Institute of Biomedical Sciences, Department of Physiology and Biophysics, Av. Prof. Lineu Prestes, 1524, Room 118, São Paulo, SP 05508-900, Brazil. Electronic address: rodrigousp@gmail.com.
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Peliciari-Garcia
mesh_terms: D056930:ARNTL Transcription Factors / Q000235:genetics; D000818:Animals; D047068:Arylalkylamine N-Acetyltransferase / Q000235:genetics; D057906:Circadian Clocks / Q000187:drug effects* / Q000235:genetics*; D056931:Cryptochromes / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D005786:Gene Expression Regulation; D008297:Male; D008550:Melatonin / Q000235:genetics; D009638:Norepinephrine / Q000494:pharmacology*; D056953:Nuclear Receptor Subfamily 1, Group D, Member 1 / Q000235:genetics; D009924:Organ Culture Techniques; D056950:Period Circadian Proteins / Q000235:genetics; D010870:Pineal Gland / Q000187:drug effects* / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014157:Transcription Factors / Q000235:genetics
chemical_list: D056930:ARNTL Transcription Factors; C538968:Cry2 protein, rat; D056931:Cryptochromes; C485975:DBP protein, rat; D004268:DNA-Binding Proteins; C498263:Nr1d1 protein, rat; D056953:Nuclear Receptor Subfamily 1, Group D, Member 1; C513311:Per2 protein, rat; D056950:Period Circadian Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; C520223:Aanat protein, rat; D047068:Arylalkylamine N-Acetyltransferase; D008550:Melatonin; D009638:Norepinephrine
keywords: AANAT; Clock genes; Melatonin; Norepinephrine; Pineal gland