·Review·
·Current Issue· ·Achieve· ·Search
Articles· ·Online
Submission· ·About IJO· PMC
The effect of lens aging and
cataract surgery on circadian rhythm
Shen-Shen Yan, Wei Wang
Department
of Ophthalmology, Peking University Third Hospital, Beijing 100191, China
Correspondence to: Wei
Wang. Department of Ophthalmology, Peking University Third Hospital, No.49
North Garden Road, Haidian District, Beijing 100191, China. puh3_ww@bjmu.edu.cn
Received:
2015-09-18
Accepted: 2016-02-14
Abstract
Many
organisms have evolved an approximately 24-hour circadian rhythm that allows
them to achieve internal physiological homeostasis with external environment.
Suprachiasmatic nucleus (SCN) is the central pacemaker of circadian rhythm, and
its activity is entrained to the external light-dark cycle. The SCN controls
circadian rhythm through regulating the synthesis of melatonin by pineal gland via a multisynaptic pathway. Light,
especially short-wavelength blue light, is the most potent environmental time
cue in circadian photoentrainment. Recently, the discovery of a novel type of
retinal photoreceptors, intrinsically photosensitive retinal ganglion cells,
sheds light on the mechanism of circadian photoentrainment and raises concerns about
the effect of ocular diseases on circadian system. With age, light
transmittance is significantly decreased due to the aging of crystalline lens,
thus possibly resulting in progressive loss of circadian photoreception. In the
current review, we summarize the circadian physiology, highlight the important
role of light in circadian rhythm regulation, discuss about the correlation
between age-related cataract and sleep disorders, and compare the effect of
blue light- filtering intraocular lenses (IOLs) and ultraviolet only filtering
IOLs on circadian rhythm.
KEYWORDS: circadian
rhythm; blue light; crystalline lens; cataract surgery; suprachiasmatic nucleus;
melatonin; ganglion cells
DOI:10.18240/ijo.2016.07.21
Citation: Yan SS, Wang W.
The effect of lens aging and cataract surgery on circadian rhythm. Int J Ophthalmol 2016;9(7):1066-1074
INTRODUCTION
Many
organisms have evolved an approximately 24-hour biological clock. This
endogenous circadian rhythm is formed by several peripheral oscillators under
the control of suprachiasmatic nucleus (SCN) in the anterior hypothalamus.
Although the SCN neurons can run autonomously, they require daily
synchronization through external time cues. Light, especially short-wavelength
blue light, is the most potent time cue in circadian photoentrainment. In 2002,
a new subtype of retinal ganglion cells, intrinsically photosensitive retinal
ganglion cells (ipRGCs), were discovered[1]. Further study found that a kind
of blue light sensitive photopigment named melanopsin expressed in ipRGCs
contributed to the synchronization of circadian rhythms with the solar day[2].
The regulation of circadian rhythm depends on a pathway that originates from
ipRGCs, via the retinohypothalmic
tract (RHT) to SCN[3]. In addition, ipRGCs also project
to olivery pretectal nucleus (OPN) controlling pupillary light reflex (PLR)
[4-5].
Sleep
disorders are common among the elderly[6]. It was proposed that age-related
loss in lens transmittance and decrease of pupillary area might be important
causes of sleep disorders and circadian rhythms disturbance in the elderly[7].
Age-related cataract is the leading cause of reversible blindness and visual
impairment throughout the world. It is characterized by lens opacity, which
leads to the gradually loss of vision and light transmission with age.
Nowadays, it is commonly believed that surgery is the only effective treatment
for age-related cataract. In addition to improving vision, cataract extraction
with intraocular lens (IOLs) implantation might affect the circadian rhythm and
sleep. There were literatures suggested that oxidative stress in the retinal
pigment epithelium (RPE) caused by blue light exposure could be an important
factor in the pathogenesis of age-related macular degeneration (AMD)[8-9].
Based on this theory, blue light-filtering IOLs was invented and applied in
clinical. However, the concern of its potential disadvantages effect on
circadian rhythm has been raised.
In
this review, we summarize the relevant circadian physiology, highlight the
important role of eye in circadian rhythm regulation, and discuss how lens
aging and cataract surgery influence the circadian system.
Suprachiasmatic Nuclei-the Master
of Circadian System In
most living organisms, the daily variations of physiological processes such as
behavior, sleep/wake cycle, subjective alertness, cognitive performance,
hormone production, and body temperature have a circadian rhythm of roughly
24h. Under normal conditions, the endogenous circadian rhythm is generated by
neurons located in SCN of the anterior hypothalamus. The SCN neurons have an
intrinsic electrical rhythm of nearly 24h even in the absence of environmental
time cues[10-11]. This rhythm reflects the auto-regulatory
transcription and translation feedback loops of the clock genes[12-14].
Although
the SCN rhythm can run autonomously, it is synchronized to the daily light/dark
cycle[12-13]. Zeitgebers are time cues that phase
shift circadian clocks, and light is the most potent zeitgeber in circadian
system; however, other non-photic signals can also entrain the circadian
rhythm, such as time of food intake, exercise, and social interactions[15].
SCN receives light information from retinal photoreceptors via the RHT, and connects to the pineal gland regulating the
synthesis and secretion of melatonin[16-18] (Figure 1). In conclusion, SCN
synchronizes the internal biological processes with the external time cues to
maintain normal physiological functions.
Figure 1 Schematic summary of primary
light-induced non-image forming pathways
The
circadian regulation of melatonin secretion (the blue pathway) and the
pupillary response (the orange pathway) depend on pathways originate from the
ipRGCs in the retina. ipRGCs receive light stimulus and project to SCN via the RHT. SCN sends inhibitory signals
to neurons of the PVN. PVN activates the preganglionic neurons of
intermediolateral column in the spinal cord, and then projects to the cervical
superior ganglion (CSG) activating melatonin secretion by pineal gland (PG).
The circulating melatonin binds to melatonin receptors and inhibits SCN neurons
from firing. ipRGCs also project to OPN, and form the pathway involving OPN, Edinger-Westpha nucleus (EW),
and ciliary ganglion (CG) regulating pupillary responses.
The
majority of SCN neurons are GABAergic[17], and they can be divided into two
subtypes according to the different neuropeptides they expressed. One subtype
expresses arginine vasopressin (AVP), while the other expresses vasoactive
intestinal polypeptide (VIP)[19-20]. AVP and VIP act on V1a/V1b
and VPAC2 receptors respectively to transmit circadian signals[21-22].
It is believed that different subtypes play different roles. Specifically,
VIPergic neurons are involved in receiving RHT and secondary visual inputs,
whereas AVPergic neurons amplify the endogenous SCN rhythms into coherent
behavioral outputs[23].
The
output of SCN is complex with major efferents going caudally into the
subparaventricular zone and dorsomedial nucleus (DMN), dorsal efferents to the
thalamus, and rostral efferents to the anterior hypothalamus and preoptic area[24-25]. DMN integrates the direct input
from SCN and the indirect input from subparaventricular zone, and then projects
to other hypothalamic areas to control circadian responses, for example sleep
and wake initiation. The efferents to paraventricular nucleus (PVN) mainly
regulate the melatonin synthesis by pineal gland.
Melatonin-the Marker of Circadian
System Melatonin is a
hormone synthesized and released by pineal gland in a cyclic pattern under the
control of SCN[26]. The chemical structure of
melatonin is N-acetyl-5-methoxytryptamine[27]. Melatonin is synthesized from
L-tryptophan, which is converted into 5-hydroxytryptophan and then into
serotonin. Serotonin is first transformed into N-acetylserotonin by the
arylalkylamine-N-acetyltransferase (AA-NAT), and then transformed to melatonin
by hydroxyindole-O-methyl transferase (HIOMT)[28-29]. The
AA-NAT is activated by norepinephrine through binding to β-adrenergic receptors[30].
Melatonin is released into circulation once produced by pineal gland. Plasma
melatonin concentration is low during the day and high during the night. The 24-hour
plasma melatonin profiles provide accurate measurement of circadian phase,
specifically, melatonin levels start to increase about 2 to 3h prior to
habitual bedtime, remain elevated during the night, peak between 02:00 to 04:00,
and rapidly decease in the following hours[31-32] (Figure 2). Dim light is
particularly important in the entrainment of circadian rhythm. Two currently
used indicators of circadian phase include the dim light melatonin onset (DLMO)
and the peak melatonin concentration at night. DLMO represents the onset of the
evening melatonin production measured in dim light and is thought to be the
most reliable circadian phase marker[31]. Moreover, the normal nocturnal
melatonin synthesis can be suppressed and phase-shifted by light, depending on
its intensity, wavelength, timing and duration[33-35].
Figure 2 Illustration of plasma melatonin
concentrations in a normal subject The DLMO and the peak
melatonin concentration are two reliable markers of circadian rhythm. At
present, there is no standard calculative method of DLMO. The calculation of
DLMO is based on a fixed threshold (time reaching 1-, 3- or 5-pg/ml), a dynamic
threshold (2 standard deviations above the mean of 3 baseline samples), or a
mathematical model (for example the “hockey-stick” method). The peak is often
reached at 02:00 to 04:00.
In
mammals, actions of melatonin are mediated by two types of melatonin receptors-MT1
and MT2[36]. Melatonin receptors belong to G protein-coupled
receptor superfamily[36]. As melatonin receptors are
widely expressed in many organs and tissues, melatonin is involved in
modulating multiple physiological activities. The rhythm of melatonin
production and the concentration of melatonin in body fluid are reliable
markers reflecting the circadian rhythm[37]. And because exogenous
administration of melatonin can improve sleep quality, melatonin is thought to
be a sleep-promoting agent in the treatment of insomnia[38], delayed
sleep phase disorder (DSPD)[39], jet lag and shift work disorders[40].
Moreover, melatonin also acts as a free-radical scavenger[41-42]. This
property of melatonin is important in protecting cells from aging and might
keep animals and human away from neurodegenerative diseases[41]. Melatonin
also has a crucial role in immunomodulation, cardiovascular function regulation
and tumor suppression function[43-44].
There
is an age-related alteration in nocturnal serum melatonin concentrations[45].
The melatonin level peaks at 3-6y, and then gradually decreases in adolescence.
With aging, the melatonin rhythm progressively dampens, with a tendency towards
phase-advance[46-47]. Moreover, some studies
reported that melatonin concentration decreased in numerous diseases[48-51].
In conclusion, whether the declination of melatonin levels is only age-related
changes， or
is related to systemic diseases still remains unclear.
Intrinsically Photosensitive
Retinal Ganglion Cells -a Novel Photoreceptor in Light Entrainment The mammalian
eye is responsible for two main light-induced functions. The most widely recognized
function is to provide visual information. However, the non-visual functions, for
example circadian photoentrainmen，are of equal importance. Several experimental
studies found that genetic ablation of rod and cone photoreceptors in animals
didn’t affect their circadian responses to light[52-54]. Moreover,
clinical findings showed that optic neuropathies selectively affected classic
photoreceptors in the outer-layer of retina could result in vision loss with
relatively preserved pupillary light reflex and stable circadian rhythm[55-56].
These results suggested that there might be another photoreceptive pathway in
the retina regulating circadian rhythm aside from the cones and rods.
In
2002, Berson et al[1]
reported a novel type of photosensitive ganglion cells in the mammalian retina.
These retinal ganglion cells express melanopsin and could depolarize to light
stimulation in absence of rods and cones, therefore, they are named ipRGCs.
Further study showed that melanopsin gene (Opn4) shared more homogenous sequence
with invertebrate rhabdomeric opsins than with vertebrate opsins[57],
suggesting that there might be a different mechanism for melanopsin
photoreception from rods and cones photopigments in vertebrates[58].
Although ipRGCs comprise only 0.2%-4% of total retinal ganglion cells in
mammalian retina[1,59-60], they mediate a broad range
of physiological responses and are divided into five types (M1-M5) according to
their morphological and physiological properties[61-62]. The M1
cells are the largest and most numerous subtypes. They project predominantly to
SCN[63-64],
and also project to OPN[65-66]. However, the non-M1 cells
show widespread projections to brain areas that involved in image formation.
The light response of ipRGCs is different from that of rods and cones. The
activation threshold of ipRGCs is higher than rods and cones, and the response
latency as well as the duration of firing are longer than rods and cones[59].
Although
ipRGCs are directly photosensitive, they also receive input from rods and
cones. The detail connections between ipRGCs and other cells in the retina are
not completely understood. Current studies discovered that ipRGCs connected to
cones via the cone bipolar cells, and
connected to rods via the amacrine
cells and rod bipolar cells[67] (Figure 3). The spectral
sensitivity of melanopsin is similar in different species with λmax
at approximately 480 nm[1,59,68-69]. Light elicits
isomerization of 11-cis retinaldehyde resulting in conformational changes in
the opsin receptor, which triggers the downstream signal transduction cascade[70].
Figure 3 The schematic of ipRGCs and their connections
in mammalian retina The ipRGCs can either
respond to light autonomously or receive light information from rod and cone
photoreceptors in regulating the non-image forming functions. Rods provide
inputs to ipRGCs mainly via rod
bipolar cells and amacrine cells. Cones provide inputs to ipRGCs through cone
bipolar cells and amacrine cells (the specific connections are depending on
different type of cones and ipRGCs).
ipRGCs
have roles in both non-image-forming photoreception and image-forming visual
function[59]. Specifically, ipRGCs have two primary non-image
forming functions: the circadian photoentrainment function via retinohypothalamic tract (RHT) projecting to the SCN[1,71],
and the regulation of pupil light reflex by projecting to the OPN[63]
(Figure 1). ipRGCs also project to intergeniculate leaflet (IGL),
subparaventricular zone (SPZ) and ventrall preoptic nucleus (VLP)，which provide
additional pathways for circadian photoentrainment[4]. For about
image-forming visual functions, evidences from recent studies indicated that
ipRGCs projected to distinct brain regions involved in spatial and
discriminative visual functions[60,72]. The intrinsic mechanism of
the melanopsin’s contribution to spatial information and visual perception, and
whether it works in humans need to be explored, for these may lead to new
prospects for restoring vision in patients who loss vision from rod and cone
disease.
Light-the Central Modulator of
the Circadian Rhythm It is generally agreed that light is crucial in
generating images. Meanwhile, many important physiological activities in human
are also influenced by retinal illumination[73-75]. These activities are regulated through
independent pathways from image formation. These pathways are referred to as
non-image-forming pathways. The most important light-induced non-image forming
functions are synchronization of the circadian clock to solar day, tracking of
seasonal changes, and regulation of sleep through the rhythmic secretion of
melatonin[74]. Light is the most potent time cue (Zeitgeber) in
circadian photoentrainment. Beyond these
functions, pupil light reflex, body temperature, hormone production, alertness
and cognitive functions are also regulated by light.
Light causes phase shifting of the circadian rhythm
depending on its duration, intensity, timing and spectrum by regulating the
expression of clock genes[76-78]. First of all, studies showed that light
administered in late night and early morning could cause phase advancing of the
circadian clock. However, light administered in early night could induce phase
delay shifts[79-81]. Secondly, regarding to the influence of intensity
on the resetting response to light,
Zeitzer et
al[82] found that exposing to
intensity greater than room light level in early biological day demonstrated
significantly more advancement in circadian clock than exposure to dim light.
In addition, Zeitzer et al[83] also found that the resetting response and
melatonin suppression by light at late biological day related to a non-linear
way to illuminance, with minimal responses below 100 lux and saturating
responses above 1000 lux. Thirdly, by comparing the phase shifting responses to
monochromatic light of different wavelengths with equal photon density, Lockley
et al[84] demonstrated that both phase shifting and
melatonin suppression responses were significantly greater in subjects exposed
to 460 nm than longer wavelength. In conclusion, light administered at biological night with high intensity and
wavelength lies in blue spectrum is more potent for circadian photoentrainment.
Sufficient light exposure at appropriate time is
the optimal time cue for circadian photoentrainment, whereas inadequate light
exposure could possibly lead to “free-running”. Free-running means independent
SCN rhythm without daily synchronization and it may lead to circadian rhythm
misalignment[85-87]. It was found that many totally blind people had
abnormal or non-entrained circadian rhythms due to inability to detect light[88-89]. These patients always suffered from insomnia and
daytime drowsiness, which might consequently do harm to psychological and
physical health. Exogenous melatonin and melatonin agonist could effectively
improve sleep quality and reset circadian clock in these patients[86-87].
The basic biological functions of light give rise
to the development of many therapeutic applications. Timed light treatments was
shown to be effective for promoting circadian entrainment, improving sleep
efficiency, and relieving symptoms of seasonal affective disorder (SAD) and
depression[39,90-91].
Lens Aging, Cataract Surgery and
Their Effects on Circadian Rhythm Numerous
studies showed that the prevalence of sleep disorders is higher in the elderly
compared to that in young people[92-93].
A multicenter epidemiologic study that enrolled more than 9000 participants
aged over 65y reported that over half of the participants complained about
symptoms relating to insomnia[94]. In human, aging is characterized
by decreased amplitude of circadian rhythm, advanced phase in circadian rhythm,
and disrupted nocturnal sleep[95-96]. These changes of circadian
rhythm with age contribute to sleep disorders in the elderly.
Sleep
disorders poses substantial risks for the development of many health problems,
including cardiovascular and mental disorders, and may contribute to increased
morbidity and mortality in the elderly. Therefore, more attention should be
paid to improve sleep quality in the elderly[95-96]. Moreover,
there are many factors that affect sleep, for example certain physical and
psychiatric comorbidities, medications, jet lag and shift work, etc.
Any
disturbance of the circadian pathway will lead to interruption of the normal
circadian rhythm. Therefore, as an important organ in circadian photoreception,
the physical and pathological changes of the eye may lead to changes in circadian
rhythm. Age-related reduction in responses to light has been found in both
animal and human experiments. It was shown that older rats needed higher light
intensity to achieve the same activity rhythm amplitude compared to younger
rats[97]. For human, a study investigated the age-related
changes in light induced melatonin suppression, and the results showed that the
elderly demonstrated significantly reduced melatonin suppression after exposing
to short wavelength light compared to the young[98]. However, a
recent study showed that in spite of decreased retinal illumination in the
elderly, melatonin suppression by nocturnal light exposure was not reduced,
however, the peak of non-visual sensitivity shifted to longer wavelengths[99].
So far, the mechanism of how ocular aging affect the circadian photoentrainment
is still unclear. More researches are needed to clarify this issue.
Cataract
is the leading cause of blindness and visual impairment throughout the world,
and age-related cataract is the most common type of cataract. With age, the
crystalline lens gradually increases in thickness and weight. The lens nucleus
undergoes compression and hardening, and the lens proteins are modified and
take on a yellow-to-brown coloration. As a result, the transparency and
refractive index of the lens are changed. These changes block the transmission
of blue light to retina, thereby reducing the blue light absorbed by ipRGCs[100-101].
Thus, cataract may possibly lead to decreased circadian photoentrainment.
Both in vitro and in vivo experiments indicated that there was a correlation between lens
aging and light transmittance. By evaluating human donor lenses over a wide
range of age between 18 to 76y, Kessel et
al[101] found that increasing age was associated with
gradually decreasing transmittance of light, especially at shorter blue wavelengths.
In recent years, the development of new apparatuses measuring the transmittance
of human crystalline lens in vivo
showed that the transmission of blue light to retina progressively decreased
with age[102-103]. In a word, the aging lens acts as a yellow
filter that attenuates blue light reaching the retina and lens aging is thought
to influence the circadian photoentrainment. Brondsted et al[104] found that the potential for
melanopsin stimulation and melatonin suppression were reduced by 0.6-0.7 percentage
point per year of life. A cross-sectional population based study by Kessel et al[100] found that
the risk of sleep disturbances was significantly increased when the
transmission of blue light was low. In addition, reduced pupil diameter[105],
loss of ipRGCs with age[56], coexistent eye diseases[106]
and reduced environmental illumination[107] may all contribute to circadian
rhythm disorders in the elderly.
Lens
extraction with IOLs implantation is the standard and only effective treatment
for age-related cataract. In addition to improving visual function, in theory, cataract
surgery is supposed to have a beneficial effect on circadian rhythm regulation for
it removes the barrier to short wavelength light optimal for circadian
photoentrainment. However, conclusions are inconsistent in different studies.
The regulation of circadian rhythms can be measured in various ways, and the
most commonly used methods are Pittsburgh Sleep Quality Index (PSQI) and
Epworth Sleepiness Score (ESS) questionnaires, actigraphy and melatonin
concentrations in body fluid. The results of a questionnaire-based
investigation revealed that there was a self-reported improvement of sleep
quality 1mo after cataract surgery[108]. Another study involved in 961
patients and with longer follow-up time also found an improvement of PSQI
overall sleep quality and sleep latency 1mo after cataract surgery, and these
effects were sustained at 6 and 12mo postoperatively[109]. Schmoll et al[110] reported a
reduction of daytime sleepiness after phacoemulsification cataract surgery by
using ESS. However, a recent randomized double-masked clinical trial by Brondsted
et al[111] showed that
PSQI global scores and the number of poor sleepers were not affected by
cataract surgery. In addition, the study results by Ayaki et al[112-113] demonstrated that there was
a significant improvement in sleep 2mo after cataract surgery with blue
light-filtering IOLs implantation, but thereafter the improvement was not statistical
significant; while, the improvement of sleep was found only in poor sleepers
after cataract surgery with UV only filtering IOLs.
In
regard to melatonin levels, contradictions also exist. Brondsted et al[111] found that the peak melatonin concentration at
night increased significantly 3wk after cataract surgery regardless of IOLs
types, while the majority of circadian and sleep-specific actigraphy parameters
did not change after surgery. However, a previous study by Tanaka et al[114] failed to
demonstrate changes in maximum melatonin concentration and time of reaching
maximum concentration after cataract surgery. Further studies of larger sample
size and standardized melatonin measurement are required to solve this
discrepancies. Considering the small number of participants, various study
design, different detecting method and bias, we could draw the conclusion that
cataract surgery do not have adversely effect on circadian rhythm and sleep.
Further randomized control studies of more participants, longer follow-up time
and standard outcome measures are needed to verify the hypothesis that
increased photoreception potentiates the input signal to SCN, leading to an
improvement in circadian entrainment and sleep quality.
Based
on results of animal and epidemiological studies that blue light contributed to
the pathogenesis of AMD[8,115], blue light-filtering IOLs
were invented and put into clinical use. In recent years, the heated debate
regarding to the advantages and disadvantages of blue light-filtering IOLs has
never stopped. The blue light-filtering IOLs has lower transmittance of blue
light to the retina than the UV light-filtering IOLs[99-101]. Concerns with blue light-filtering IOLs about
its negative effects on circadian rhythms have been raised. It has been found
that blue light-filtering IOLs had similar transmittance to that of 53-year-old
adults[116]. Some studies suggested that the decreased blue
light transmission had negative effects on sleep[117-118].
However, most of the recent studies hold the opinion that blue light-filtering
IOLs do not cause significant disruption to the circadian rhythm compared to UV
only filtering IOLs[104,111,119-120]. Although blue
light-filtering IOLs had lower blue light transmission than neutral UV only
filtering IOLs, the clinical effect of blue light-filtering IOLs was relatively
small. The results above do not prove that there is no difference between the
two types of IOLs except large scale clinical trials and systemic analysis are
carried out to determine whether it is better to implant a blue light-filtering
IOLs or a UV only filtering IOLs.
CONCLUSION AND PERSPECTIVES
Light
is crucial in human health. The eye plays an important role in light-induced non-image
forming responses by ipRGCs transducing light information into electrical
signals and then transmit to non-visual brain centers including the SCN. SCN is
the pacemaker of circadian system and controls many physiological processes.
Normal SCN function and sufficient illumination are necessary for maintaining
body homeostasis, for example, the normal everyday secretion rhythm of
hormones, stable emotions, normal cognitive functions and sleep/wake cycle.
Ocular
aging leads to gradually loss of retinal illumination caused by decreasing
crystalline lens transmittance and pupillary area, which could consequently
limit the photoreception for non-image forming functions. Recent studies found
that glaucoma might do damage to the ipRGCs, which could possibly be harmful to
the circadian system. Moreover, aging is always associated with numerous
systemic diseases that may cause degeneration of SCN neurons or dampen the SCN
signals output. All these situations consequently increase the risks of
sleeping disorders, psychological illness, dementia, and cardiovascular
disease.
Surgery
is the only effective treatment for age-related cataract. It removes a barrier
to light optimal for both vision forming and circadian phtoreception. In
theory, age-related cataract patients might benefit from cataract surgery not
only in the improvement of visual acuity, but also in the improvement of sleep
quality and circadian regulation. However, the exact effects of cataract
surgery on the circadian system are still not well understood. And whether
there are different circadian photoentrainment effects in blue light-filtering
IOLs and UV only filtering IOLs is also unclear. To further investigate these
problems, large scale, randomized controlled clinical trials with standard
outcome measures are needed.
ACKNOWLEDGEMENTS
Conflicts of Interest: Yan SS,
None; Wang W, None.
REFERENCES
1 Berson DM, Dunn FA, Takao M. Phototransduction
by retinal ganglion cells that set the circadian clock. Science 2002;295(5557):1070-1073. [CrossRef] [PubMed]
2
Berson DM. Strange vision: ganglion cells as circadian photoreceptors. Trends Neurosci 2003;26(6):314-320. [CrossRef]
3
Benarroch EE. Suprachiasmatic nucleus and melatonin: reciprocal interactions
and clinical correlations. Neurology
2008;71(8):594-598. [CrossRef] [PubMed]
4
Gooley JJ, Lu J, Fischer D, Saper CB. A broad role for melanopsin in nonvisual
photoreception. J Neurosci 2003;23(18):7093-7106. [PubMed]
5
Joyce DS, Feigl B, Cao D, Zele AJ. Temporal characteristics of melanopsin
inputs to the human pupil light reflex. Vision
Res 2015;107:58-66. [CrossRef]
[PubMed]
[PMC free article]
6
Neikrug AB, Ancoli-Israel S. Sleep disorders in the older adult -a mini-review.
Gerontology 2010;56(2):181-189. [CrossRef] [PubMed] [PMC free article]
7
Charman WN. Age, lens transmittance, and the possible effects of light on
melatonin suppression. Ophthalmic Physiol
Opt 2003;23(2):181-187. [CrossRef]
8
Tomany SC, Cruickshanks KJ, Klein R, Klein BE, Knudtson MD. Sunlight and the
10-year incidence of age-related maculopathy: the Beaver Dam Eye Study. Arch Ophthalmol 2004;122(5):750-757. [CrossRef]
[PubMed]
9
Blasiak J, Petrovski G, Veréb Z, Facskó A, Kaarniranta K. Oxidative stress,
hypoxia, and autophagy in the neovascular processes of age-related macular
degeneration. Biomed Res Int 2014;2014:768026.
[CrossRef] [PubMed] [PMC free article]
10
Lee HS, Nelms JL, Nguyen M, Silver R, Lehman MN. The eye is necessary for a
circadian rhythm in the suprachiasmatic nucleus. Nat Neurosci 2003;6(2):111-112. [CrossRef] [PubMed]
11
Reppert SM, Weaver DR. Molecular analysis of mammalian circadian rhythms. Annu Rev Physiol 2001;63:647-676. [CrossRef] [PubMed]
12
Zee PC, Manthena P. The brain's master circadian clock: implications and
opportunities for therapy of sleep disorders. Sleep Med Rev 2007;11(1):59-70. [CrossRef]
[PubMed]
13
Challet E. Minireview: Entrainment of the suprachiasmatic clockwork in diurnal
and nocturnal mammals. Endocrinology
2007;148(12):5648-5655. [CrossRef] [PubMed]
14
Takahashi JS, Hong HK, Ko CH, McDearmon EL. The genetics of mammalian circadian
order and disorder: implications for physiology and disease. Nat Rev Genet 2008;9(10):764-775. [CrossRef] [PubMed] [PMC free article]
15
Bailey SM, Udoh US, Young ME. Circadian regulation of metabolism. J Endocrinol 2014;222(2):R75-R96. [CrossRef] [PubMed] [PMC free article]
16
Hannibal J, Fahrenkrug J. Neuronal input pathways to the brain's biological
clock and their functional significance. Adv
Anat Embryol Cell Biol 2006;182:1-71. [PubMed]
17
Abrahamson EE, Moore RY. Suprachiasmatic nucleus in the mouse: retinal
innervation, intrinsic organization and efferent projections. Brain Res 2001;916(1-2):172-191. [CrossRef]
18
Hankins MW, Peirson SN, Foster RG. Melanopsin: an exciting photopigment. Trends Neurosci 2008;31(1):27-36. [CrossRef]
[PubMed]
19
Saper CB, Lu J, Chou TC, Gooley J. The hypothalamic integrator for circadian
rhythms. Trends Neurosci
2005;28(3):152-157. [CrossRef] [PubMed]
20
Moore RY, Speh JC, Leak RK. Suprachiasmatic nucleus organization. Cell Tissue Res 2002;309(1):89-98. [CrossRef]
[PubMed]
21
Bittman EL. Vasopressin: more than just an output of the circadian pacemaker?
Focus on "Vasopressin receptor V1a regulates circadian rhythms of
locomotor activity and expression of clock-controlled genes in the
suprachiasmatic nuclei". Am J
Physiol Regul Integr Comp Physiol 2009;296(3):R821-R823. [CrossRef]
[PubMed]
[PMC free article]
22
An S, Tsai C, Ronecker J, Bayly A, Herzog ED. Spatiotemporal distribution of
vasoactive intestinal polypeptide receptor 2 in mouse suprachiasmatic nucleus. J Comp Neurol 2012;520(12):2730-2741. [CrossRef] [PubMed] [PMC free article]
23
Brancaccio M, Enoki R, Mazuski CN, Jones J, Evans JA, Azzi A. Network-mediated
encoding of circadian time: the suprachiasmatic nucleus (SCN) from genes to
neurons to circuits, and back. J Neurosci
2014;34(46):15192-15199. [CrossRef]
[PubMed]
[PMC free article]
24
Mistlberger RE. Circadian regulation of sleep in mammals: role of the
suprachiasmatic nucleus. Brain Res Brain
Res Rev 2005;49(3):429-454. [CrossRef] [PubMed]
25
Kalsbeek A, Palm IF, La Fleur SE, Scheer FA, Perreau-Lenz S, Ruiter M, Kreier
F, Cailotto C, Buijs RM. SCN outputs and the hypothalamic balance of life. J Biol Rhythms 2006;21(6):458-469. [CrossRef]
[PubMed]
26
Morin LP. SCN organization reconsidered. J
Biol Rhythms 2007;22(1):3-13. [CrossRef]
[PubMed]
27
Lerner AB, Case JD, Takahashi Y. Isolation of melatonin and
5-methoxyindole-3-acetic acid from bovine pineal glands. J Biol Chem 1960;235:1992-1997. [PubMed]
28
Simonneaux V, Ribelayga C. Generation of the melatonin endocrine message in
mammals: a review of the complex regulation of melatonin synthesis by
norepinephrine, peptides, and other pineal transmitters. Pharmacol Rev 2003;55(2):325-395. [CrossRef] [PubMed]
29
Maronde E, Stehle JH. The mammalian pineal gland: known facts, unknown facets. Trends Endocrinol Metab 2007;18(4):142-149.
[CrossRef]
[PubMed]
30
Roseboom PH, Coon SL, Baler R, McCune SK, Weller JL, Klein DC. Melatonin
synthesis: analysis of the more than 150-fold nocturnal increase in serotonin
N-acetyltransferase messenger ribonucleic acid in the rat pineal gland. Endocrinology 1996;137(7):3033-3045. [PubMed]
31
Benloucif S, Burgess HJ, Klerman EB, Lewy AJ, Middleton B, Murphy PJ, Parry BL,
Revell VL. Measuring melatonin in humans. J
Clin Sleep Med 2008;4(1):66-69. [PMC free article] [PubMed]
32
Pandi-Perumal SR, Smits M, Spence W, Srinivasan V, Cardinali DP, Lowe AD,
Kayumov L. Dim light melatonin onset (DLMO): a tool for the analysis of
circadian phase in human sleep and chronobiological disorders. Prog Neuropsychopharmacol Biol Psychiatry 2007;31(1):1-11.
[CrossRef] [PubMed]
33
Chang AM, Santhi N, St Hilaire M, Gronfier C, Bradstreet DS, Duffy JF, Lockley
SW, Kronauer RE, CzeislerCA. Human responses to bright light of different
durations. J Physiol (Lond) 2012;590(13):3103-3112.
[CrossRef] [PubMed] [PMC free article]
34
Khalsa SB, Jewett ME, Cajochen C, Czeisler CA. A phase response curve to single
bright light pulses in human subjects. J
Physiol (Lond) 2003;549(Pt 3):945-952. [CrossRef]
[PubMed]
[PMC free article]
35
Smith MR, Eastman CI. Phase delaying the human circadian clock with
blue-enriched polychromatic light. Chronobiol
Int 2009;26(4):709-725. [CrossRef]
[PubMed]
[PMC free article]
36
Dubocovich ML, Delagrange P, Krause DN, Sugden D, Cardinali DP, Olcese J.
International Union of Basic and Clinical Pharmacology. LXXV. Nomenclature,
classification, and pharmacology of G protein-coupled melatonin receptors. Pharmacol Rev 2010;62(3):343-380. [CrossRef] [PubMed] [PMC free article]
37
Benloucif S, Guico MJ, Reid KJ, Wolfe LF, L'Hermite-Baleriaux M, Zee PC.
Stability of melatonin and temperature as circadian phase markers and their
relation to sleep times in humans. J Biol
Rhythms 2005;20(2):178-188. [CrossRef]
[PubMed]
38
Bliwise DL, Ansari FP. Insomnia associated with valerian and melatonin usage in
the 2002 National Health Interview Survey.
Sleep 2007;30(7):881-884. [PMC free article] [PubMed]
39
Wilhelmsen-Langeland A, Saxvig IW, Pallesen S, Nordhus IH, Vedaa Ø, Lundervold
AJ, Bjorvatn B. A randomized controlled trial with bright light and melatonin
for the treatment of delayed sleep phase disorder: effects on subjective and
objective sleepiness and cognitive function. J Biol Rhythms 2013;28(5):306-321. [CrossRef]
[PubMed]
40
Zee PC, Goldstein CA. Treatment of shift work disorder and jet lag. Curr Treat Options Neurol 2010;12(5):396-411.
[CrossRef]
[PubMed]
41
Bonnefond A, Clément N, Fawcett K, et al.
Rare MTNR1B variants impairing melatonin receptor 1B function contribute to
type 2 diabetes. Nat Genet 2012;44(3):297-301.
[CrossRef] [PubMed] [PMC free article]
42
Tan DX, Manchester LC, Esteban-Zubero E, Zhou Z, Reiter RJ. Melatonin as a
Potent and Inducible Endogenous Antioxidant: Synthesis and Metabolism. Molecules 2015;20(10):18886-18906. [CrossRef]
[PubMed]
43
Rondanelli M, Faliva MA, Perna S, Antoniello N. Update on the role of melatonin
in the prevention of cancer tumorigenesis and in the management of cancer
correlates, such as sleep-wake and mood disturbances: review and remarks. Aging Clin Exp Res 2013;25(5):499-510. [CrossRef]
[PubMed]
[PMC free article]
44
Dominguez-Rodriguez A, Abreu-Gonzalez P, Sanchez-Sanchez JJ, Kaski JC, Reiter
RJ. Melatonin and circadian biology in human cardiovascular disease. J Pineal Res 2010;49(1):14-22. [CrossRef]
45
Waldhauser F, Weiszenbacher G, Tatzer E, Gisinger B, Waldhauser M, Schemper M,
Frisch H. Alterations in nocturnal serum melatonin levels in humans with growth
and aging. J Clin Endocrinol Metab 1988;66(3):648-652.
[CrossRef]
[PubMed]
46
Iguichi H, Kato KI, Ibayashi H. Age-dependent reduction in serum melatonin
concentrations in healthy human subjects. J
Clin Endocrinol Metab 1982;55(1):27-29. [CrossRef] [PubMed]
47
Claustrat B, Brun J, Chazot G. The basic physiology and pathophysiology of
melatonin. Sleep Med Rev 2005;9(1):11-24. [CrossRef]
[PubMed]
48
Chen W, Cao H, Lu QY, Wang N, Zhao SZ, Xu X, Zheng Z. Urinary
6-sulfatoxymelatonin level in diabetic retinopathy patients with type 2
diabetes. Int J Clin Exp Pathol
2014;7(7):4317-4322. [PMC free article] [PubMed]
49
Schernhammer ES, Berrino F, Krogh V, Secreto G, Micheli A, Venturelli E, Sieri
S, Sempos CT, Cavalleri A, Schünemann HJ, Strano S, Muti P. Urinary
6-sulfatoxymelatonin levels and risk of breast cancer in postmenopausal women. J Natl Cancer Inst 2008;100(12):898-905.
[CrossRef] [PubMed] [PMC free article]
50
Young ME, Bray MS. Potential role for peripheral circadian clock dyssynchrony
in the pathogenesis of cardiovascular dysfunction. Sleep Med 2007;8(6):656-667. [CrossRef]
[PubMed]
[PMC free article]
51 Shekleton JA, Parcell DL, Redman JR,
Phipps-Nelson J, Ponsford JL, Rajaratnam SM. Sleep disturbance and melatonin
levels following traumatic brain injury. Neurology 2010;74(21):1732-1738. [CrossRef]
[PubMed]
[PMC free article]
52 Foster RG, Provencio I, Hudson D, Fiske S, De
Grip W, Menaker M. Circadian photoreception in the retinally degenerate mouse
(rd/rd). J Comp Physiol A 1991;169(1):39-50. [CrossRef]
53 Freedman MS, Lucas RJ, Soni B, von Schantz M,
Muñoz M, David-Gray Z, Foster R. Regulation of mammalian circadian behavior by
non-rod, non-cone, ocular photoreceptors. Science 1999;284(5413):502-504. [CrossRef]
54 Lucas RJ, Freedman MS, Lupi D, Munoz M,
David-Gray ZK, Foster RG. Identifying the photoreceptive inputs to the
mammalian circadian system using transgenic and retinally degenerate mice. Behav
Brain Res 2001;125(1-2):97-102. [CrossRef]
55 La Morgia C, Ross-Cisneros FN, Hannibal J,
Montagna P, Sadun AA, Carelli V. Melanopsin-expressing retinal ganglion cells:
implications for human diseases. Vision Res 2011;51(2):296-302. [CrossRef]
[PubMed]
56 La Morgia C, Ross-Cisneros FN, Sadun AA,
Hannibal J, Munarini A, Mantovani V, Barboni P, Cantalupo G, Tozer KR, Sancisi
E, Salomao SR, Moraes MN, Moraes-Filho MN, Heegaard S, Milea D, Kjer P,
Montagna P, Carelli V. Brain 2010;133(Pt 8):2426-2438. [CrossRef] [PubMed] [PMC free article]
57 Borges R, Johnson WE, O'Brien SJ, Vasconcelos
V, Antunes A. The role of gene duplication and unconstrained selective
pressures in the melanopsin gene family evolution and vertebrate circadian
rhythm regulation. PLoS One 2012;7(12):e52413. [CrossRef]
[PubMed]
[PMC free article]
58 Bellingham J, Chaurasia SS, Melyan Z, Liu C,
Cameron MA, Tarttelin EE, Iuvone PM, Hankins MW, Tosini G, Lucas RJ. Evolution
of melanopsin photoreceptors: discovery and characterization of a new
melanopsin in nonmammalian vertebrates. PLoS Biol 2006;4(8):e254. [CrossRef]
[PubMed]
[PMC free article]
59 Dacey DM, Liao HW, Peterson BB, Robinson FR,
Smith VC, Pokorny J, Yau KW, Gamlin PD. Melanopsin-expressing ganglion cells in
primate retina signal colour and irradiance and project to the LGN. Nature
2005;433(7027):749-754. [CrossRef] [PubMed]
60 Ecker JL, Dumitrescu ON, Wong KY, Alam NM,
Chen SK, LeGates T, Renna JM, Prusky GT, Berson DM, Hattar S.
Melanopsin-expressing retinal ganglion-cell photoreceptors: cellular diversity
and role in pattern vision. Neuron 2010;67(1):49-60. [CrossRef]
[PubMed]
[PMC free article]
61 Sand A, Schmidt TM, Kofuji P. Diverse types of
ganglion cell photoreceptors in the mammalian retina. Prog Retin Eye Res 2012;31(4):287-302.
[CrossRef] [PubMed] [PMC free article]
62 Zhao X, Stafford BK, Godin AL, King WM, Wong
KY. Photoresponse diversity among the five types of intrinsically
photosensitive retinal ganglion cells. J Physiol (Lond) 2014;592(7):1619-1636.
[CrossRef] [PubMed] [PMC free article]
63 Hattar S, Kumar M, Park A, Tong P, Tung J, Yau
KW, Berson DM. Central projections of melanopsin-expressing retinal ganglion
cells in the mouse. J Comp Neurol 2006;497(3):326-349. [CrossRef] [PubMed] [PMC free article]
64 Gooley JJ, Lu J, Chou TC, Scammell TE, Saper
CB. Melanopsin in cells of origin of the retinohypothalamic tract. Nat Neurosci
2001;4(12):1165. [CrossRef] [PubMed]
65 Schmidt TM, Chen SK, Hattar S. Intrinsically
photosensitive retinal ganglion cells: many subtypes, diverse functions. Trends
Neurosci 2011;34(11):572-580. [CrossRef]
[PubMed]
[PMC free article]
66 Baver SB, Pickard GE, Sollars PJ, Pickard GE.
Two types of melanopsin retinal ganglion cell differentially innervate the
hypothalamic suprachiasmatic nucleus and the olivary pretectal nucleus. Eur J
Neurosci 2008;27(7):1763-1770. [CrossRef] [PubMed]
67 Lucas RJ, Peirson SN, Berson DM, Brown TM,
Cooper HM, Czeisler CA, Figueiro MG, Gamlin PD, Lockley SW, O’Hagan JB, Price
LL, Provencio I, Skene DJ, Brainard GC. Measuring and using light in the
melanopsin age. Trends Neurosci 2014;37(1):1-9. [CrossRef]
[PubMed]
[PMC free article]
68 Bailes HJ, Lucas RJ. Human melanopsin forms a
pigment maximally sensitive to blue light (lambdamax approximately 479 nm) supporting
activation of G(q/11) and G(i/o) signalling cascades. Proc Biol Sci 2013;280(1759):20122987.
[CrossRef]
[PubMed]
[PMC free article]
69 Panda S, Nayak SK, Campo B, Walker JR,
Hogenesch JB, Jegla T. Illumination of the melanopsin signaling pathway. Science
2005;307(5709):600-604. [CrossRef] [PubMed]
70 Hatori M, Panda S. The emerging roles of
melanopsin in behavioral adaptation to light. Trends Mol Med 2010;16(10):435-446.
[CrossRef] [PubMed] [PMC free article]
71 Do MT, Yau KW. Intrinsically photosensitive
retinal ganglion cells. Physiol Rev 2010;90(4):1547-1581. [CrossRef]
[PubMed]
[PMC free article]
72 Brown TM, Tsujimura S, Allen AE, Wynne J,
Bedford R, Vickery G, Vugler A, Lucas RJ. Melanopsin-based brightness
discrimination in mice and humans. Curr Biol 2012;22(12):1134-1141. [CrossRef]
[PubMed]
[PMC free article]
73 Fonken LK, Nelson RJ. The effects of light at
night on circadian clocks and metabolism. Endocr Rev 2014;35(4):648-670. [CrossRef] [PubMed]
74 LeGates TA, Fernandez DC, Hattar S. Light as a
central modulator of circadian rhythms, sleep and affect. Nat Rev Neurosci 2014;15(7):443-454.
[CrossRef] [PubMed] [PMC free article]
75 Forbes D, Blake CM, Thiessen EJ, Peacock S,
Hawranik P. Light therapy for improving cognition, activities of daily living,
sleep, challenging behaviour, and psychiatric disturbances in dementia. Cochrane
Database Syst Rev 2014;26(2):CD003946. [CrossRef]
76 McMahon DG, Iuvone PM, Tosini G. Circadian
organization of the mammalian retina: from gene regulation to physiology and
diseases. Prog Retin Eye Res 2014;39:58-76. [CrossRef] [PubMed] [PMC free article]
77 Albrecht U, Sun ZS, Eichele G, Lee CC. A
differential response of two putative mammalian circadian regulators, mper1 and
mper2, to light. Cell 1997;91(7):1055-1064. [CrossRef]
78 Schwartz WJ, Tavakoli-Nezhad M, Lambert CM,
Weaver DR, de la Iglesia HO. Distinct patterns of Period gene expression in the
suprachiasmatic nucleus underlie circadian clock photoentrainment by advances
or delays. Proc Natl Acad Sci U S A 2011;108(41):17219-17224. [CrossRef] [PubMed] [PMC free article]
79 Minors DS, Waterhouse JM, Wirz-Justice A. A
human phase-response curve to light. Neurosci Lett 1991;133(1):36-40. [CrossRef]
80 Wright HR, Lack LC, Kennaway DJ. Differential
effects of light wavelength in phase advancing the melatonin rhythm. J Pineal
Res 2004;36(2):140-144. [CrossRef]
81 St Hilaire MA, Gooley JJ, Khalsa SB, Kronauer
RE, Czeisler CA, Lockley SW. Human phase response curve to a 1 h pulse of
bright white light. J Physiol (Lond) 2012;590(13):3035-3045. [CrossRef]
[PubMed]
[PMC free article]
82 Zeitzer JM, Khalsa SB, Boivin DB, Duffy JF,
Shanahan TL, Kronauer RE, Czeisler CA. Temporal dynamics of late-night photic
stimulation of the human circadian timing system. Am J Physiol Regul Integr
Comp Physiol 2005;289(3):R839-R844. [CrossRef]
[PubMed]
83 Zeitzer JM, Dijk DJ, Kronauer R, Brown E,
Czeisler C. Sensitivity of the human circadian pacemaker to nocturnal light:
melatonin phase resetting and suppression. J Physiol (Lond) 2000;526 Pt
3:695-702. [CrossRef] [PubMed] [PMC free article]
84 Lockley SW, Brainard GC, Czeisler CA. High
sensitivity of the human circadian melatonin rhythm to resetting by short
wavelength light. J Clin Endocrinol Metab 2003;88(9):4502-4505. [CrossRef] [PubMed]
85 Sack RL, Auckley D, Auger RR, Carskadon MA,
Wright KP Jr, Vitiello MV, Zhdanova IV; American Academy of Sleep Medicine.
Circadian rhythm sleep disorders: part II, advanced sleep phase disorder,
delayed sleep phase disorder, free-running disorder, and irregular sleep-wake
rhythm. An American Academy of Sleep Medicine review. Sleep 2007;30(11):1484-1501.
[PMC free article] [PubMed]
86 Sack RL, Brandes RW, Kendall AR, Lewy AJ.
Entrainment of free-running circadian rhythms by melatonin in blind people. N
Engl J Med 2000;343(15):1070-1077. [CrossRef]
[PubMed]
87 Stahl SM. Mechanism of action of tasimelteon
in non-24 sleep-wake syndrome: treatment for a circadian rhythm disorder in
blind patients. CNS Spectr 2014;19(6):475-478. [CrossRef]
[PubMed]
88 Lockley SW, Skene DJ, Arendt J, Tabandeh H,
Bird AC, Defrance R. Relationship between melatonin rhythms and visual loss in
the blind. J Clin Endocrinol Metab 1997;82(11):3763-3770. [CrossRef]
89 Flynn-Evans EE, Tabandeh H, Skene DJ, Lockley
SW. Circadian Rhythm Disorders and Melatonin Production in 127 Blind Women with
and without Light Perception. J Biol Rhythms 2014;29(3):215-224. [CrossRef]
[PubMed]
90 Figueiro MG, Lesniak NZ, Rea MS. Implications
of controlled short-wavelength light exposure for sleep in older adults. BMC
Res Notes 2011;4:334. [CrossRef] [PubMed] [PMC free article]
91 Glickman G, Byrne B, Pineda C, Hauck WW,
Brainard GC. Light therapy for seasonal affective disorder with blue
narrow-band light-emitting diodes (LEDs). Biol Psychiatry 2006;59(6):502-507. [CrossRef]
[PubMed]
92 Mellinger GD, Balter MB, Uhlenhuth EH.
Insomnia and its treatment. Prevalence and correlates. Arch Gen Psychiatry 1985;42(3):225-232.
[CrossRef]
93 Paudel ML, Taylor BC, Diem SJ, Stone KL,
Ancoli-Israel S, Redline S, Ensrud KE; Osteoporotic Fractures in Men Study
Group. Association between depressive symptoms and sleep disturbances in
community-dwelling older men. J Am Geriatr Soc 2008;56(7):1228-1235. [CrossRef] [PubMed] [PMC free article]
94 Foley DJ, Monjan AA, Brown SL, Simonsick EM,
Wallace RB, Blazer DG. Sleep complaints among elderly persons: an epidemiologic
study of three communities. Sleep 1995;18(6):425-432. [PubMed]
95 Ancoli-Israel S. Sleep and its disorders in
aging populations. Sleep Med 2009;10 Suppl 1:S7-S11. [CrossRef]
[PubMed]
96 Monk TH. Aging human circadian rhythms:
conventional wisdom may not always be right. J Biol Rhythms 2005;20(4):366-374.
[CrossRef]
[PubMed]
97 Witting W, Mirmiran M, Bos NP, Swaab DF.
Effect of light intensity on diurnal sleep-wake distribution in young and old
rats. Brain Res Bull 1993;30(1-2):157-162. [CrossRef]
98 Herljevic M, Middleton B, Thapan K, Skene DJ.
Light-induced melatonin suppression: age-related reduction in response to short
wavelength light. Exp Gerontol 2005;40(3):237-242. [CrossRef]
[PubMed]
99 Najjar RP, Chiquet C,
Teikari P, Cornut PL, Claustrat B, Denis P, Cooper HM, Gronfier C. Aging of
non-visual spectral sensitivity to light in humans: compensatory mechanisms? PLoS
One 2014;9(1):e85837.
100 Kessel L, Siganos G, Jorgensen T, Larsen M.
Sleep disturbances are related to decreased transmission of blue light to the
retina caused by lens yellowing. Sleep 2011;34(9):1215-1219. [CrossRef]
101 Kessel L, Lundeman JH, Herbst K, Andersen TV,
Larsen M. Age-related changes in the transmission properties of the human lens
and their relevance to circadian entrainment. J Cataract Refract Surg 2010;36(2):308-312.
[CrossRef]
[PubMed]
102 Sakanishi Y, Awano M, Mizota A, Tanaka M,
Murakami A, Ohnuma K. Age-related changes in spectral transmittance of the
human crystalline lens in situ. Ophthalmologica 2012;228(3):174-180. [CrossRef] [PubMed]
103 Broendsted AE, Hansen MS, Lund-Andersen H,
Sander B, Kessel L. Human lens transmission of blue light: a comparison of
autofluorescence-based and direct spectral transmission determination. Ophthalmic
Res 2011;46(3):118-124. [CrossRef] [PubMed]
104 Brondsted AE, Lundeman JH, Kessel L. Short
wavelength light filtering by the natural human lens and IOLs - implications
for entrainment of circadian rhythm. Acta Ophthalmol 2013;91(1):52-57. [CrossRef] [PubMed]
105 Birren JE, Casperson RC, Botwinick J. Age
changes in pupil size. J Gerontol 1950;5(3):216-221. [CrossRef]
106 Gracitelli CP, Duque-Chica GL, Roizenblatt M,
Moura AL, Nagy BV, Ragot de Melo G, Borba PD, Teixeira SH, Tufik S, Ventura DF,
Paranhos A Jr. Ophthalmology 2015;122(6):1139-1148. [CrossRef] [PubMed]
107 Hood B, Bruck D, Kennedy G. Determinants of
sleep quality in the healthy aged: the role of physical, psychological,
circadian and naturalistic light variables. Age Ageing 2004;33(2):159-165. [CrossRef]
108 Asplund R, Ejdervik Lindblad B. The
development of sleep in persons undergoing cataract surgery. Arch Gerontol
Geriatr 2002;35(2):179-187. [CrossRef] [PubMed] [PMC free article]
109 Alexander I, Cuthbertson FM, Ratnarajan G,
Safa R, Mellington FE, Foster RG, Downes SM, Wulff K. Impact of cataract
surgery on sleep in patients receiving either ultraviolet-blocking or
blue-filtering intraocular lens implants. Invest Ophthalmol Vis Sci 2014;55(8):4999-5004.
[CrossRef] [PubMed]
110 Schmoll C, Khan A, Aspinall P, Goudie C, Koay
P, Tendo C, Cameron J, Roe J, Deary I, Dhillon B. New light for old eyes:
comparing melanopsin-mediated non-visual benefits of blue-light and UV-blocking
intraocular lenses. Br J Ophthalmol 2014;98(1):124-128. [CrossRef]
[PubMed]
111 Brondsted AE, Sander B, Haargaard B,
Lund-Andersen H, Jennum P, Gammeltoft S, Kessel L. The Effect of Cataract
Surgery on Circadian Photoentrainment: A Randomized Trial of Blue-Blocking
versus Neutral Intraocular Lenses. Ophthalmology 2015;122(10):2115-2124. [CrossRef] [PubMed] [PMC free article]
112 Ayaki M, Muramatsu M, Negishi K, Tsubota K.
Improvements in sleep quality and gait speed after cataract surgery. Rejuvenation
Res 2013;16(1):35-42. [CrossRef] [PubMed] [PMC free article]
113 Ayaki M, Negishi K, Tsubota K. Rejuvenation
effects of cataract surgery with ultraviolet blocking intra-ocular lens on
circadian rhythm and gait speed. Rejuvenation Res 2014;17(4):359-365. [CrossRef]
114 Tanaka M, Hosoe K, Hamada T, Morita T. Change
in sleep state of the elderly before and after cataract surgery. J Physiol
Anthropol 2010;29(6):219-224. [CrossRef]
[PubMed]
115 Narimatsu T, Negishi K, Miyake S, Hirasawa M,
Osada H, Kurihara T, Tsubota K, Ozawa Y. Blue light-induced inflammatory marker
expression in the retinal pigment epithelium-choroid of mice and the protective
effect of a yellow intraocular lens material in vivo. Exp Eye Res 2015;132:48-51.
[CrossRef] [PubMed]
116 Henderson BA, Grimes KJ. Blue-blocking IOLs:
a complete review of the literature. Surv Ophthalmol 2010;55(3):284-289. [CrossRef]
[PubMed]
117 Mainster MA. Intraocular lenses should block
UV radiation and violet but not blue light. Arch Ophthalmol 2005;123(4):550-555.
[CrossRef]
[PubMed]
[PMC free article]
118 Lee RM, Lam FC, Liu CS. Blue-blocking
intraocular implants should be used routinely during phacoemulsification
surgery-no. Eye (Lond) 2012;26(11):1400-1401. [CrossRef] [PubMed] [PMC free article]
119 Symes RJ, Cuthbertson FM. Blue-blocking
intraocular implants should be used routinely during phacoemulsification
surgery-yes. Eye (Lond) 2012;26(11):1397-1399. [CrossRef]
[PubMed]
120 Landers
JA, Tamblyn D, Perriam D. Effect of a blue-light-blocking intraocular lens on
the quality of sleep. J Cataract
Refract Surg 2009;35(1):83-88.
[Top]