Abstract:
:In mammals, the suprachiasmatic nuclei (SCN) constitute the main circadian clock, receiving input from the retina which allows synchronization of endogenous biological rhythms with the daily light/dark cycle. Over the year, the SCN encodes photoperiodic variations through duration of melatonin secretion, with abundant nocturnal levels in winter and lower levels in summer. Thus, light information is critical to regulate seasonal reproduction in many species and is part of the central photoperiodic integration. Since intrinsically photosensitive retinal ganglion cells (ipRGCs) are vital for circadian photoentrainment and other non-visual functions, we studied the contribution of ipRGCs in photoperiod integration in C3H retinal degeneration 1 (rd1) mice. We assessed locomotor activity and melatonin secretion in mice exposed to short or long photoperiods. Our results showed that rd1 mice are still responsive to photoperiod variations in term of locomotor activity, melatonin secretion and regulation of the reproductive axis. In addition, retinas of animals exposed to short photoperiod exhibit higher melanopsin labelling intensity compared to the long photoperiod condition, suggesting seasonal-dependent changes within this photoreceptive system. These results show that ipRGCs in rd1 mice can still measure photoperiod and suggest a key role of melanopsin cells in photoperiod integration and the regulation of seasonal physiology.
journal_name
J Pineal Resjournal_title
Journal of pineal researchauthors
Leclercq B,Hicks D,Laurent Vdoi
10.1111/jpi.12711subject
Has Abstractpub_date
2020-12-16 00:00:00pages
e12711eissn
0742-3098issn
1600-079Xpub_type
杂志文章abstract::The incidence of chronic obstructive pulmonary disease (COPD) has substantially increased in recent decade. Cigarette smoke (CS) is the most important risk factor in the development of COPD. In this study, we investigated the effects of melatonin on the development of COPD using a CS and lipopolysaccharide (LPS)-induc...
journal_title:Journal of pineal research
pub_type: 杂志文章
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更新日期:2015-01-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
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更新日期:2009-01-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1989.tb00666.x
更新日期:1989-01-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1989.tb00911.x
更新日期:1989-01-01 00:00:00
abstract::Aging induces changes in several organs and tissues, such as the liver, and this process might be due to oxidative damage caused by free radicals and inflammatory mediators. Melatonin is a secretory product with well-known antioxidant properties. The aim of this study was to investigate the effect of melatonin adminis...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2004.00199.x
更新日期:2005-05-01 00:00:00
abstract::Melatonin influences plant innate immunity through the mitogen-activated protein kinase (MAPK) pathway. However, the most upstream MAPK component in melatonin signaling and the dependence of generation of a reactive oxygen species (ROS) burst on melatonin synthesis and signaling remain unclear. In this study, treatmen...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/jpi.12379
更新日期:2017-03-01 00:00:00
abstract::Recent investigations have demonstrated that melatonin influences carbohydrate metabolism mediated by insulin-inhibiting effects on pancreatic β-cells. This study evaluated whether melatonin has also an effect on pancreatic α-cells and glucagon expression as well as the glucagon secretion in vitro and in vivo. Glucago...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2010.00848.x
更新日期:2011-04-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1987.tb00852.x
更新日期:1987-01-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1984.tb00202.x
更新日期:1984-01-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/jpi.12681
更新日期:2020-10-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2005.00238.x
更新日期:2005-09-01 00:00:00
abstract::Recent investigations of our group established that melatonin modulates hormone secretion of pancreatic islets via melatonin receptor types MT1 and MT2. Expression of MT1 and MT2 has been shown in mouse, rat, and human pancreatic islets as well as in the β-, α-, and δ-cell lines INS-1, αTC1.9, and QGP-1. In view of th...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/jpi.12480
更新日期:2018-08-01 00:00:00
abstract::As for many hormones, melatonin levels in the blood suggest that it is discharged from the pineal gland in a pulsatile manner. Recently, the existence of short-term episodes, superimposed on the circadian pattern of circulating melatonin, has been questioned. Because plasma melatonin levels reflect not only the secret...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1995.tb00151.x
更新日期:1995-04-01 00:00:00
abstract::N-acetylserotonin methyltransferase (ASMT), the last enzyme in the synthesis of melatonin, catalyzes N-acetylserotonin into melatonin. For the first time, we cloned ASMT from rice through the analysis of recombinant Escherichia coli harboring putative rice O-methyltransferase (OMT) cDNAs. In total, 18 full-length cDNA...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2010.00841.x
更新日期:2011-04-01 00:00:00
abstract::Light and electron microscopic demonstrations for acid phosphatase (AcPase) activity in the chicken pineal gland were studied with special reference to the changes induced by the light-dark cycle. AcPase-positive lysosomes and Golgi cisternae and vesicles located in the pinealocyte in the light period are well develop...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1989.tb00407.x
更新日期:1989-01-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1991.tb00466.x
更新日期:1991-10-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1994.tb00109.x
更新日期:1994-08-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/jpi.12126
更新日期:2014-04-01 00:00:00
abstract::Irradiation of the melatonin metabolite N(1)-acetyl-N(2)-formyl-5-methoxykynuramine (AFMK) with UV light of 254 nm causes the release of carbon monoxide (CO) and, thus, deformylation to N(1)-acetyl-5-methoxykynuramine (AMK). Liberation of CO was demonstrated by reduction of PdCl(2) to metallic palladium, under avoidan...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2007.00550.x
更新日期:2008-05-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2005.00256.x
更新日期:2005-11-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1996.tb00242.x
更新日期:1996-03-01 00:00:00
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journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1998.tb00550.x
更新日期:1998-10-01 00:00:00
abstract::Methamphetamine (METH) is a potent psychostimulant drug that may cause neuronal cell degeneration. The underlying mechanisms of METH-induced neuronal toxicity remains poorly understood. In this study, we investigated an important role of calpain-dependent cascades in methamphetamine-induced toxicity in human dopaminer...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2009.00731.x
更新日期:2010-03-01 00:00:00
abstract::Melatonin and its precursor, l-tryptophan, have been shown to exert gastroprotective effects in animals, but their influence on the gastric damage by aspirin (ASA) in humans has been sparingly investigated. In this study, we designed to determine the effects of melatonin and l-tryptophan on ASA-induced gastric mucosal...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.2010.00755.x
更新日期:2010-05-01 00:00:00
abstract::Seasonal day length has been linked to the prevalence of mood disorders, and however, the mechanisms underlying this relationship remain unknown. Previous work in our laboratory has shown that developmental exposure to seasonal photoperiods has enduring effects on the activity of mouse dorsal raphe serotonergic neuron...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/jpi.12705
更新日期:2020-11-19 00:00:00
abstract::Classical anticancer therapies often are ineffective in patients with malignant glioma who have a survival of <1 year. Our previous studies showed a potent inhibitory effect of melatonin on glioma cell proliferation. This effect seems to be mediated by the well-known antioxidant properties of this molecule and the neg...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2007.00468.x
更新日期:2007-10-01 00:00:00
abstract::We examined the association between 6-sulphatoxymelatonin (6-SMT) excretion and sleep in 68 volunteers 60-79 years of age who complained of insomnia or depression. An Actillume wrist monitor was worn for 5-7 consecutive days and nights in home-living conditions. Activity was used to estimate total sleep time (TST) and...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1998.tb00526.x
更新日期:1998-04-01 00:00:00
abstract::Human placental mitochondria might be a significant source of NADPH- and iron-dependent production of reactive oxygen species (ROS). Preeclampsia is believed to be a consequence of overproduction of ROS in human placenta. The experimental results presented here show that melatonin inhibits NADPH- and iron-dependent li...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2010.00779.x
更新日期:2010-09-01 00:00:00
abstract::Although there is an increasing evidence that the pineal gland may play a role in human malignancy, the studies on melatonin concentrations in different types of malignant tumors brought about controversial results. However, changes in melatonin concentrations have been observed in some types of human malignant tumors...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2005.00221.x
更新日期:2005-08-01 00:00:00
abstract::Melatonin is a very potent and efficient endogenous radical scavenger. The pineal indolamine reacts with the highly toxic hydroxyl radical and provides on-site protection against oxidative damage to biomolecules within every cellular compartment. Melatonin acts as a primary non-enzymatic antioxidative defense against ...
journal_title:Journal of pineal research
pub_type: 杂志文章,评审
doi:10.1111/j.1600-079x.1993.tb00498.x
更新日期:1993-05-01 00:00:00