Lights Off Research Articles

Signal-on/signal-off bead-based assays for the multiplexed monitoring of base excision repair activities by flow cytometry.

As the support of all living kingdoms' genetic information, the integrity of the DNA biomolecule must be preserved. To that goal, cells have evolved specific DNA repair pathways to thwart a large diversity of chemical substances and radiations that alter the DNA structure and lead to the development of pathologies such as cancers or neurodegenerative diseases. When dysregulated, activity rates of various actors of DNA repair can play a key role in carcinogenesis as well as in drugs resistance or hypersensitivity mechanisms. For the last 10years, new complementary treatments have aimed at targeting specific enzymes responsible for such resistances. It is therefore crucial for biomedical research and clinical diagnosis to develop fast and sensitive tools able to measure the activity rate of DNA repair enzymes. In this work, a new assay for measuring enzymatic activities using microbeacons (µBs) is expounded. µB refers to microsphere functionalized by hairpin-shaped nucleic acid probes containing a single site-specific lesion in the stem and modified with chromophores. Following the processing of the lesion by the targeted protein, µB is cleaved and either lights off (signal-off strategy) or on (signal-on), depending on the use of fluorescent or profluorescent probes, respectively. After an optimization phase of the assay, we reported the combined analysis of restriction enzyme, AP-endonuclease, and DNA N-glycosylase by real-time monitoring followed by a flow cytometry measurement. As proofs of concept, we demonstrated the potential of the biosensor for highlighting DNA repair inhibitors and discriminating cell lines from their enzymatic activities.

Time-restricted feeding alters the efficiency of mammary tumor growth

ABSTRACT Disruption of circadian rhythms has detrimental host consequences. Indeed, both clinical and foundational science demonstrate a clear relationship between disruption of circadian rhythms and cancer initiation and progression. Because timing of food intake can act as a zeitgeber (i.e., entrainment signal) for the circadian clock, and most individuals in the developed world have access to food at all times of the day in a “24/7” society, we sought to determine the effects of timing of food intake on mammary tumor growth. We hypothesized that restricting access to food to during the inactive phase would accelerate tumor growth. Adult female Balb/C mice received a unilateral orthotopic injection of murine mammary carcinoma 4T1 cells into the ninth inguinal mammary gland. Beginning on the day of tumor injection and continuing until the end of the experiment, mice were food restricted to their active phase (ZT12 (lights off)- ZT0 (lights on), inactive phase (ZT0 – ZT12), or had ad libitum access to food. Mice that were food restricted to their inactive phase displayed a significant increase in body mass on days 7 and 14 of tumor growth relative to active phase or ad libitum fed mice. Additionally, mice fed during their inactive phase demonstrated a 20% reduction in food consumption relative to mice fed during their active phase and a 17% reduction in food consumption relative to ab libitum fed mice. Tumor volume was not significantly different between groups. However, food restricting mice to their inactive phase increased mammary tumor growth efficiency (i.e., mg of tumor mass per gram of food intake) relative to mice fed during the active phase and approached significance (p = .06) relative to ad libitum fed mice. To determine a potential explanation for the increased tumor growth efficiency, we examined rhythms of activity and body temperature. Mice fed during the inactive phase displayed significantly disrupted daily activity and body temperature rhythms relative to both other feeding regimens. Together, these data demonstrate that improperly timed food intake can have detrimental consequences on mammary tumor growth likely via disrupted circadian rhythms.

Limited changes in locomotor recovery and unaffected white matter sparing after spinal cord contusion at different times of day.

The circadian gene expression rhythmicity drives diurnal oscillations of physiological processes that may determine the injury response. While outcomes of various acute injuries are affected by the time of day at which the original insult occurred, such influences on recovery after spinal cord injury (SCI) are unknown. We report that mice receiving moderate, T9 contusive SCI at ZT0 (zeitgeber time 0, time of lights on) and ZT12 (time of lights off) showed similar hindlimb function recovery in the Basso mouse scale (BMS) over a 6 week post-injury period. In an independent study, no significant differences in BMS were observed after SCI at ZT18 vs. ZT6. However, the ladder walking test revealed modestly improved performance for ZT18 vs. ZT6 mice at week 6 after injury. Consistent with those minor effects on functional recovery, terminal histological analysis revealed no significant differences in white matter sparing at the injury epicenter. Likewise, blood-spinal cord barrier disruption and neuroinflammation appeared similar when analyzed at 1 week post injury at ZT6 or ZT18. Therefore, locomotor recovery after thoracic contusive SCI is not substantively modulated by the time of day at which the neurotrauma occurred.

Optogenetic Activation of Arcuate Kisspeptin Neurons Generates a Luteinizing Hormone Surge-Like Secretion in an Estradiol-Dependent Manner.

Traditionally, the anteroventral periventricular (AVPV) nucleus has been the brain area associated with luteinizing hormone (LH) surge secretion in rodents. However, the role of the other population of hypothalamic kisspeptin neurons, in the arcuate nucleus (ARC), has been less well characterized with respect to surge generation. Previous experiments have demonstrated ARC kisspeptin knockdown reduced the amplitude of LH surges, indicating that they have a role in surge amplification. The present study used an optogenetic approach to selectively stimulate ARC kisspeptin neurons and examine the effect on LH surges in mice with different hormonal administrations. LH level was monitored from 13:00 to 21:00 h, at 30-minute intervals. Intact Kiss-Cre female mice showed increased LH secretion during the stimulation period in addition to displaying a spontaneous LH surge around the time of lights off. In ovariectomized Kiss-Cre mice, optogenetic stimulation was followed by a surge-like secretion of LH immediately after the stimulation period. Ovariectomized Kiss-Cre mice with a low dose of 17β-estradiol (OVX+E) replacement displayed a surge-like increase in LH release during period of optic stimulation. No LH response to the optic stimulation was observed in OVX+E mice on the day of estradiol benzoate (EB) treatment (day 1). However, after administration of progesterone (day 2), all OVX+E+EB+P mice exhibited an LH surge during optic stimulation. A spontaneous LH surge also occurred in these mice at the expected time. Taken together, these results help to affirm the fact that ARC kisspeptin may have a novel amplificatory role in LH surge production, which is dependent on the gonadal steroid milieu.

A Novel Method for Measuring the Pupil Diameter and Pupillary Light Reflex of Healthy Volunteers and Patients With Intracranial Lesions Using a Newly Developed Pupilometer.

Background: Physicians currently measure the pupil diameter and the pupillary light reflex with visual observations using a ruler and a traditional penlight, leading to possibly inaccurate and subjective assessments. Although a mobile pupillometer has been developed and is available in clinical settings, this device can only assess one pupil at a time. Hence, an indirect pupillary light reflex, including those under irradiation to the opposite side of pupil, cannot be evaluated. Consequently, we have developed a new automatic mobile pupilometer, the Hitomiru®, with Hitomiru Co., Ltd. (Tokyo, Japan). This device is a two-glass type pupilometer with a video recording system. The pupil diameter and light reflex of both pupils can be measured simultaneously; therefore, both indirect and direct light reflexes can be assessed.Purpose: To evaluate the clinical ability of the Hitomiru® pupilometer to assess the pupil diameter and the pupillary light reflex of healthy volunteers and patients with intracranial lesions in an intensive care unit (ICU).Methods: Twenty-five healthy volunteers and five ICU patients with intracranial lesions on only the left side were assessed using the Hitomiru® pupilometer. The protocol was as follows: infrared light was applied to both pupils, followed by visible light to the right pupil, infrared light to both pupils, visible light to the left pupil, and then infrared light to both pupils. All the intervals were 2 s, and the dynamics of pupil diameters on both sides were continuously recorded.Results: The healthy adults had approximately 0.5 mm anisocoria, miosis was harder, and mydriasis was less with increased age. There were several differences in miosis rates, miosis times, and mydriasis rates between the healthy adults and the patients with intracranial lesions with both direct irradiation and indirect irradiation.Conclusions: The initial trial estimated and digitally recorded direct and indirect light reflexes, including rapidity of miosis after direct and indirect lights on, and mydriasis after direct and indirect lights off. The Hitomiru® pupilometer was a useful device to digitally record and investigate the relationship between pupil reflexes and intracranial diseases.

Effects of Flashing Blue Lights Mounted on Paving Equipment on Vehicle Speed Behavior in Work Zones

Vehicle speed in work zones is a significant concern to state transportation agencies and their construction partners. Prior research indicates that law enforcement vehicles within a work zone with active flashing lights result in reduced vehicle speeds. Placement of flashing blue lights on construction equipment during nighttime construction work has also been identified as a potential control measure to reduce speeds. The goal of this research study is to determine the impact of flashing blue lights on construction equipment on the speed of passing vehicles in mobile work zones. The research design consisted of a controlled experiment involving flashing blue lights mounted on the rear of a paver during mainline paving operations on three case study projects on high speed roadways at night in Oregon. Vehicle speed data were collected during multiple work shifts for each case study, both with and without the flashing blue lights on. The experimental results reveal that vehicle speed is affected by the presence of flashing blue lights during nighttime work. With the blue lights flashing and at distances upstream of the paver where the driver can see and react to the blue lights, mean vehicle speeds tended to be 4.3–25.7 km/h slower than when the blue lights were off. Closer to, immediately adjacent to, and downstream of the paver, the difference in the mean speed with the blue lights on was typically less or not significant; in some cases and mostly downstream of the paver location, the mean speeds were higher with the blue lights on than with the blue lights off. The speed differential (i.e., the speed prior to the work zone minus the speed in the work zone) was measured as 4.8–11.3 km/h greater with the blue lights turned on than with the blue lights off. The results support construction contractors and state departments of transportation for decision making about the use of flashing blue lights on equipment in work zones. The researchers recommend using flashing blue lights on paving equipment during nighttime operations if allowed by local laws to reduce the speed in the work zone and increase worker and driver safety. This research contributes to the construction industry by providing quantitative evidence of the extent to which flashing blue lights mounted on paving equipment impact vehicle speeds in work zones. Recently, all stakeholders, including the Oregon Department of Transportation, law enforcement, and contractors, have agreed to use the flashing blue lights on paving equipment in Oregon during the 2021 construction season.

Diel and Circadian Patterns of Locomotor Activity in the Adults of Diamondback Moth (Plutella xylostella).

The Diamondback Moth (Plutella xylostella) is a highly destructive lepidopteran pest of cruciferous crops. However, there still is relatively little known about the locomotor activities of diel and the circadian patterns in P. xylostella. Here, we present an analysis of the diel locomotion of P. xylostella under several laboratory settings. We established a system for measuring the individual locomotor activities of P. xylostella and found that both males and females showed a nocturnal pattern of activity under 26 or 20 °C LD conditions, with activity peaking immediately after lights off and quickly declining after lights on. In addition, we showed that it is difficult to assess the free-running circadian rhythms of P. xylostella under 26 °C DD conditions. However, we found that males showed a higher power, rhythm index (RI) and rhythmic ratio than females under 20 °C DD conditions, which indicated that males in low-temperature conditions are much more suitable to study the free-running circadian rhythms of P. xylostella. The findings of this study will help us to have a better understanding of the diel activity of P. xylostella and may provide a foundation for the development of an effective pest management strategy.

Discrepancies between self-reported and device-measured sleep parameters in adults with multiple sclerosis.

Sleep problems are a common consequence of multiple sclerosis; however, there is limited evidence regarding the agreement between device-measured and self-reported sleep parameters in adults with multiple sclerosis. The present study examined the agreement between self-reported and device-measured parameters of sleep quality in a sample of adults with multiple sclerosis. Participants (n = 49) completed a 7-day sleep diary and wore a wrist-worn ActiGraph GT3×+ (ActiGraph Corp., Pensecola, FL) for seven consecutive nights to quantify self-reported and device-measured sleep parameters, respectively. There was a significant discrepancy between self-reported and device-measured parameters of total time in bed (mean difference = 19.8 [51.3] min), sleep onset latency (mean difference = 22.2 [19.5] min), and frequency of awakenings during the night (mean difference = 12.8 [6.8]). Intraclass correlation estimates indicated poor agreement between methods on most parameters, except for total time in bed (intraclass correlation = 0.80). Bland-Altman plots suggested that total time in bed and total sleep time had acceptable levels of agreement and linear regression analyses indicated that sleep onset latency (F = 113.91, B = -1.34, P < .001), number of awakenings (F = 543.34, B = 1.85, P < .001), and sleep efficiency (F = 18.39, B = -0.77, P < .001) had significant proportional bias. Our results draw attention to the discrepancies between sleep parameter measurements and highlight the importance of including both self-report and device-measured outcomes for a complete and accurate representation of sleep in adults with multiple sclerosis. Cederberg KLJ, Mathison BG, Schuetz ML, Motl RW. Discrepancies between self-reported and device-measured sleep parameters in adults with multiple sclerosis. J Clin Sleep Med. 2022;18(2):415-421.

The dual orexin receptor antagonist almorexant blocks the sleep-disrupting and daytime stimulant effects of methamphetamine in rhesus monkeys

BackgroundThe present study investigated the effects of the dual orexin receptor antagonist (DORA) almorexant, a sleep-modulating drug, on the sleep-disrupting effects of methamphetamine in adult rhesus monkeys. MethodsMonkeys were fitted with primate collars to which actigraphy monitors were attached. To determine the effects of methamphetamine on daytime activity and sleep-like parameters, monkeys were given acute injections of vehicle or methamphetamine (0.03, 0.1 or 0.3 mg/kg, i.m.) in the morning (9:00 h) (n = 4 males). We then determined the ability of almorexant to alter the daytime and/or sleep-like effects of the largest (effective) dose of methamphetamine. Vehicle or almorexant (1, 3 or 10 mg/kg, i.m.) were administered in the evening (16:30 h, 1.5 h before “lights off”) following morning (9:00 h) administration of methamphetamine (0.3 mg/kg, i.m.), or as a pretreatment (8:30 h) before methamphetamine injections (9:00 h) (n = 4 males). The ability of almorexant (10 mg/kg) to improve sleep-like behaviors also was assessed in a group of monkeys quantitatively identified with short-duration sleep (n = 2 males, 2 females). ResultsMorning methamphetamine administration dose-dependently impaired sleep in rhesus monkeys (0.3 mg/kg significantly increased sleep latency and decreased sleep efficiency). Administration of almorexant, both as a pretreatment or as an evening treatment, improved methamphetamine-induced sleep impairment in a dose dependent manner. Morning pretreatment with almorexant also blocked the daytime stimulant effects of methamphetamine. Evening, but not morning, treatment with almorexant in a group of monkeys with baseline short-duration sleep improved sleep measures. ConclusionsOur findings indicate that orexin receptor systems are involved in methamphetamine-induced hyperarousal and sleep disruption.

Diurnal burden of spontaneous seizures in early epileptogenesis in the post-kainic acid rat model of epilepsy.

Patients with epilepsy can experience diurnal seizure patterns. However, few studies in rodent models of temporal lobe epilepsy (TLE) routinely quantify the diurnal pattern of spontaneous recurrent seizures (SRS), and those that have conducted such assessments used small groups. This study thus aimed to define whether there was a diurnal pattern of SRS in the early phases of epileptogenesis in a large cohort (n = 40) of post‐kainic acid (KA)‐induced status epilepticus (SE) male Sprague Dawley rats. Rats were monitored by continuous 24/7 video‐EEG in two‐week epochs up to 6 weeks post‐KA‐induced SE. The total number of SRS by 6 weeks post‐SE correlated to body weight at the time of SE insult (R 2 = .1465, P = .0143). The total number of spontaneous behavioral and electrographic seizures, seizure severity, and seizure burden was recorded during lights ON (light) or lights OFF (dark) phases. All measures significantly increased with time post‐SE; we detected significantly more seizures during the lights OFF phase of the post‐SE monitoring periods. Moreover, a subset of rats demonstrated marked seizure preference in the lights OFF phase. Our study confirms that a diurnal pattern of SRS is variably detectable in early epileptogenesis in this model of TLE.

The Circadian Clock Gene Bmal1 Modulates Myometrium Contractile Function in Pregnant Mice

Caesarian section should be avoided unless medically required. Caesarian section is often a result of failed labor enhancement. While most natural births occur at night, labor enhancement is often scheduled during the day. We propose that the disparity between the commonly used timing of labor enhancement in the clinic, from the timing of natural birth, could contribute to the high rate of labor induction failure. Oxytocin receptor agonists are the most used labor enhancing agents. In pregnant non-human primates, oxytocin enhances uterine contractions more efficiently at night than during the day, suggesting a daily change in uterine sensitivity to oxytocin in pregnancy. To identify the molecular mechanisms generating daily changes in uterine function, we here explore the role of the molecular clock gene, Bmal1 (Brain and muscle ARNTL1-like), in the pregnant mouse myometrium. BMAL1 is a transcription factor required to generated circadian rhythms at the cellular level. We hypothesize that Bmal1 in uterine myometrial cells generates circadian rhythms and establishes the daily change in uterine contractile response to oxytocin. To evaluate circadian rhythms ex vivo, we collected myometrium samples from the validated circadian Per2:luciferase reporter mice at gestation day 17-18. We found that the pregnant mouse myometrium possesses circadian rhythms, which are generated by the molecular clock, as triple transgenic Per2:luciferase mice with Bmal1 conditionally deleted in the myometrium (cKO) do not have rhythmic expression of the Per2:luciferase reporter. To determine if BMAL1 is required to establish uterine contractions, we used a myograph to measure ex vivo uterine contractions at gestation day 17-18. In controls, uterine contraction force was significantly higher at ZT15 (3h after lights OFF) versus ZT3 (3h after lights ON). Interestingly, our preliminary data show increased basal contractile force at ZT15 in cKO as compared to controls. In addition, the cKO uterus contracted stronger to oxytocin than controls. Our findings identify Bmal1 as a clock gene modulating basal contractions in the mouse uterus and indicate Bmal1 might be a regulator of uterine sensitivity to oxytocin. Future work will focus on identifying the molecular mechanisms driven by BMAL1 to regulate uterine function in pregnancy. This work has the potential to provide insights into how we can improve labor enhancing treatment strategies in the clinic in the future.

134 Acute effects of methadone, buprenorphine or naltrexone on sleep-like parameters evaluated with actigraphy in male rhesus monkeys

Abstract Introduction Opioid use disorder (OUD) is a significant public health problem, and it has been associated with the emergence of sleep disturbances. Effective treatment options for OUD exist, including medication-assisted therapy with methadone or buprenorphine. However, emerging evidence suggests that these treatments also may be associated with significant sleep impairment. The extent to which these effects are a result of the medication or an effect of chronic opioid use remains unknown. In the present study, we investigated the acute effects of methadone, buprenorphine or naltrexone in male rhesus monkeys in order to understand whether pharmacological treatment with these drugs per se would have deleterious effects on sleep. Methods Adult naïve male rhesus macaques (Macaca mulatta, n=5) maintained on a 12h/12h light/dark cycle were fitted with primate collars to which actigraphy monitors were attached. Actigraphy recording was conducted during baseline conditions and following acute injections of vehicle, methadone (0.03 – 1.0 mg/kg, i.m.), buprenorphine (0.01 – 1.0 mg/kg, i.m.) or naltrexone (0.03 – 1.0 mg/kg, i.m.) in the morning (10h, 4h after “lights on”) or in the evening (16:30h, 1.5h before “lights off”). Results Morning treatment with methadone or buprenorphine dose-dependently impaired sleep in rhesus monkeys, with at least one dose significantly increasing sleep latency and decreasing sleep efficiency. Evening treatment with methadone or buprenorphine also impaired sleep, with lower doses significantly inducing sleep alterations compared to morning treatments. The effects of buprenorphine on sleep was a biphasic function, with the highest doses not disrupting sleep. Treatment with naltrexone significantly improved sleep-like measures in rhesus monkeys, with evening treatments improving measures of both sleep latency and sleep efficiency. Conclusion Acute administration of methadone and buprenorphine induced marked sleep impairment in rhesus monkeys, even when the drugs were administered in the morning. Unexpectedly, acute administration of the opioid antagonist naltrexone significantly improved sleep-like measures. Our findings show that the currently available pharmacotherapies for OUD significantly affect sleep in naïve monkeys, and that opioid mechanisms yet to be determined may play a significant role in sleep-wake regulation. Support (if any) Supported by NIH grants DA049886 to L.F.B.; DA048586 to C.A.Z.; DA039167 to K.B.F.; DA011792, DA043204 and DA046778 to J.K.R..

Growth Hormone Secretion Does Not Increase After Interleukin-2 Administration in Healthy Men

Context: Interleukin-2 (IL2), a proinflammatory cytokine, is used for treatment of malignancies. Increased cortisol and ACTH were noted, but GH secretion was not investigated in detail. This is the first study in healthy men which uses moderate high IL2 doses as used in cancer treatment. Objective: The goal of this study was to quantify GH secretion after a single sc injection of IL2 in young and older healthy men in relation to dose, age and body composition. Design: This was a placebo-controlled, blinded, prospectively randomized cross-over study in 17 young subjects (mean age 24.1 yr) and 18 older subjects (mean age 63.9 yr). The subjects underwent 24 h of blood sampling at 10-min intervals, starting at 1800 h. At 2000 h IL2 (3 or 6 million units per m2 body surface) or saline was injected sc. Lights were off between 2300 and 0700 h. Outcome Measures: Deconvolution analysis of GH. Abdominal visceral fat (AVF) was calculated from single slice CT. Results: GH secretion (pulsatile and total) was negatively related to AVF (R=0.67, P<0.0001) and to age (R=0.56, P=0.001). These relations were maintained after IL2 administration. GH profiles were pulsatile under both experimental conditions. Since the effect of IL2 might be limited in time, GH deconvolution analyses were performed on the complete 24 h data series, the period with lights off and 6 h after IL2 administration. Total 24 h GH secretion decreased non-significantly from 74.6 ±10.2 to 67.5±7.4 µg/L (P=0.25) and pulsatile secretion from 69.4±9.8 to 62.2±7.4 µg/L (P=0.23). In the GLM procedure the effect of IL2 treatment was borderline significant (P=0.08), no interaction with age (P=0.28), but borderline with IL2 dose (P=0.07), and caused by decreased GH secretion (88 to 67 µg/L) at a low dose IL2. In a sub-analysis of the two age groups no effect on GH secretion in the older group was noted, in contrast to young subjects, especially on low dose IL2 (P=0.07). The analysis was refined further by calculating cumulative pulse masses in 2-h bins. By this approach it could be demonstrated that the cumulative GH pulse mass in older subjects across the 24 h was unchanged, while that in young subjects was temporarily inhibited in the bins between midnight and 0400 h (P=0.019 and 0.038). Conclusion: This study demonstrated that IL2 temporarily diminished GH secretion in young but not elderly volunteers. Pituitary hormone secretion by IL2 has not been studied as extensively as other cytokines, including IL1, IL6 and TNF. IL2 stimulates ACTH and TSH, inhibits LH and has no effect on GH secretion by rat pituitary (PNAS 58:185,1993). In patients with renal cancer IL2 infusion has no effect on GH levels (Anti-Cancer Res 10:753,1990. The present findings extend these observations to a large group of healthy volunteers, in whom we demonstrated previously suppression of the gonadal axis and activation of the HPA-axis (JCEM 101:539,2016, Endocr Connect 9:637,2010).

Time-Restricted Feeding Regulates Circadian Rhythm of Murine Uterine Clock

ABSTRACTBackgroundSkipping breakfast is associated with dysmenorrhea in young women. This suggests that the delay of food intake in the active phase impairs uterine functions by interfering with circadian rhythms.ObjectivesTo examine the relation between the delay of feeding and uterine circadian rhythms, we investigated the effects of the first meal occasion in the active phase on the uterine clock.MethodsZeitgeber time (ZT) was defined as ZT0 (08:45) with lights on and ZT12 (20:45) with lights off. Young female mice (8 wk of age) were divided into 3 groups: group I (ad libitum consumption), group II (time-restricted feeding during ZT12–16, initial 4 h of the active period), and group III (time-restricted feeding during ZT20–24, last 4 h of the active period, a breakfast-skipping model). After 2 wk of dietary restriction, mice in each group were killed at 4-h intervals and the expression profiles of uterine clock genes, Bmal1 (brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein 1), Per1 (period circadian clock 1), Per2, and Cry1 (cryptochrome 1), were examined.ResultsqPCR and western blot analyses demonstrated synchronized circadian clock gene expression within the uterus. Immunohistochemical analysis confirmed that BMAL1 protein expression was synchronized among the endometrium and myometrium. In groups I and II, mRNA expression of Bmal1 was elevated after ZT12 at the start of the active phase. In contrast, Bmal1 expression was elevated just after ZT20 in group III, showing that the uterine clock rhythm had shifted 8 h backward. The changes in BMAL1 protein expression were confirmed by western blot analysis.ConclusionsThis study is the first to indicate that time-restricted feeding regulates a circadian rhythm of the uterine clock that is synchronized throughout the uterine body. These findings suggest that the uterine clock system is a new candidate to explain the etiology of breakfast skipping–induced uterine dysfunction.

Renal Mitochondrial Gene Expression is Dependent on Time of Day in Diet‐induced Obesity

Obesity is an independent risk factor in the development of nephropathy and is associated with aberrations in renal energy metabolism. The circadian clock affects oxygen consumption and renal excretory rhythms in mice. However, the relationships between time of food intake, dietary fat content, and renal mitochondrial gene expression have not been explored. We hypothesized that feeding behaviors such as dietary fat content and circadian aspects such as the time of day and time of food intake would alter renal mitochondrial gene expression. Eight-week-old male C57Bl/6 mice were placed on a high (45%) fat or normal (10%) fat diet. After 20 weeks on their diets, the high fat diet group was further split into an ad libitum or reverse feeding schedule where food availability was restricted to the 12h lights on period. After 2 weeks of restricted feeding, mice were anesthetized with 4% isoflurane and euthanized in 4h intervals over a 24h period (ZT1, 5, 9, 13, 17, 21). Kidneys were removed and the cortex, outer and inner medulla were dissected and snap frozen in liquid nitrogen. Samples were stored at -80°C until used for analysis. We selected outer medulla samples from the ZT5 (lights on, inactive period) and ZT17 (lights off, active period) timepoints for analysis because these are associated with nadir and peak levels of energy metabolism in other tissues. Mitochondrial gene expression was measured in 84 genes by mouse-specific microarray analysis (RT2 Profiler PCR Array; Qiagen; Germantown, MD). Fold change/regulation was calculated using the delta-delta CT method. Mitochondria-specific genes within the outer medulla of diet-induced-obese mice display a pattern of expression that appears to be dependent upon the dietary fat content and time of day, but not the timing of food intake. When comparing the normal fat diet at the ZT5 and ZT17 timepoints, 24 genes were upregulated and 39 were downregulated consistent with a time-of-day difference in mitochondrial function. Comparing the high fat diet at the same timepoints yielded 18 upregulated genes and only one downregulated gene suggesting a loss of time-of-day mitochondrial function due to diet-induced obesity. When comparing the normal fat and high fat diet at ZT5, 23 genes were upregulated and 39 genes were downregulated. However, comparing the normal fat and high fat diets at ZT17 resulted in 43 upregulated genes and 20 downregulated genes, suggesting a differential effect of obesity at different times. When the high fat diet was restricted to the active period, 27 genes were differentially expressed between ZT5 and ZT17 indicating a minor improvement in circadian expression. Interestingly, many of the differentially expressed genes are involved in pathways related to membrane polarization and small molecule transport. Our results suggest that there indeed is an effect of time of day on the renal mitochondrial milieu, particularly in the context of diet induced obesity and specifically within the outer medulla. This concurs with previous observations that changes in oxygen consumption within peripheral tissues are under circadian regulation.

Issue Cover (April 2021)

Journal of NeurochemistryVolume 157, Issue 1 Issue CoverFree Access Issue Cover (April 2021) First published: 05 April 2021 https://doi.org/10.1111/jnc.15058 Read the full article: ‘How to time the time -A preface to the special issue Circadian Rhythms in the Brain’ by J. H. Stehle, A. Zemmar, L. Hausmann (J. Neurochem. 2021, vol. 157 (1), pp. 6–10) on doi:10.1111/jnc.15311 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Abstract Front cover: In vitro visualization of endogenous rhythmic oscillation in the mouse suprachiasmatic nucleus (SCN) with a circadian (circa: about; dies: day) phase length. Image Content: Shown are six selected images taken from an explanted coronal brain slice from a transgenic PER1-luciferase transgenic mouse, containing the region of the hypothalamic suprachiasmatic nucleus (SCN). Pictures were taken at indicated circadian times (CT), with CT0 corresponding to ‘lights on’ and CT12 corresponding to ‘lights off’ for the animal prior to tissue preparation. SCN slices were cultured in complete darkness with the medium containing luciferin. Pictures were extracted from a video, with images sampled in 10 minutes time bins. Note the increasing bioluminescence with in vitro progressing CT, peaking during subjective mid-day. The visualization shows the paired structure of the mouse SCN, separated by the third ventricle and located directly dorsal of the optic chiasm (A. Jilg and J.H. Stehle, unpublished). Read the full article ‘How to time the time -A preface to the special issue Circadian Rhythms in the Brain’ by J. H. Stehle, A. Zemmar, L. Hausmann (J. Neurochem. 2021, vol. 157 (1), pp. 6–10) on doi:10.1111/jnc.15311 Volume157, Issue1Special Issue: Circadian Rhythms in the BrainApril 2021 RelatedInformation

Turning to the dark side: LED light at night alters the activity and species composition of a foraging bat assemblage in the northeastern United States.

Artificial light at night (ALAN) is a rapidly intensifying form of environmental degradation that can impact wildlife by altering light‐mediated physiological processes that control a broad range of behaviors. Although nocturnal animals are most vulnerable, ALAN's effects on North American bats have been surprisingly understudied. Most of what is known is based on decades‐old observations of bats around street lights with traditional lighting technologies that have been increasingly replaced by energy‐efficient broad‐spectrum lighting, rendering our understanding of the contemporary effects of ALAN on North American bats even less complete. We experimentally tested the effects of broad‐spectrum ALAN on presence/absence, foraging activity, and species composition in a Connecticut, USA bat community by illuminating foraging habitat with light‐emitting diode (LED) floodlights and comparing acoustic recordings between light and dark conditions. Lighting dramatically decreased presence and activity of little brown bats (Myotis lucifugus), which we detected on only 14% of light nights compared with 65% of dark (lights off) and 69% of control (lights removed) nights. Big brown bat (Eptesicus fuscus) activity on light nights averaged only half that of dark and control nights. Lighting did not affect presence/absence of silver‐haired bats (Lasionycteris noctivagans), but decreased their activity. There were no effects on eastern red bats (Lasiurus borealis) or hoary bats (L. cinereus), which have been described previously as light‐tolerant. Aversion to lighting by some species but not others caused a significant shift in community composition, thereby potentially altering competitive balances from natural conditions. Our results demonstrate that only a small degree of ALAN can represent a significant form of habitat degradation for some North American bats, including the endangered little brown bat. Research on the extent to which different lighting technologies, colors, and intensities affect these species is urgently needed and should be a priority in conservation planning for North America's bats.

Sleep time and efficiency in patients undergoing laboratory-based polysomnography.

Sleep quality in patients studied with laboratory-based polysomnography may differ from sleep quality in patients studied at home but remains clinically relevant and important to describe. We assessed objective sleep quality and explored factors associated with poor sleep in patients undergoing laboratory-based polysomnography. We reviewed diagnostic polysomnography studies from a 10-year period at a single sleep center. Total sleep time (TST) and sleep efficiency (SE) were assessed as markers of sleep quality. Poor sleep was defined as TST ≤ 4 hours or SE ≤ 50%. Multivariable analysis was performed to determine associations between objective sleep quality as an outcome and multiple candidate predictors including age, sex, race, body mass index, comorbidities, severity of obstructive sleep apnea, and central nervous system medications. Among 4957 patients (age 53 ± 15 years), average TST and median SE were 5.8 hours and 79%, respectively. There were 556 (11%) and 406 (8%) patients who had poor sleep based on TST and SE, respectively. In multivariable analysis, those who were older (per 10 years: 1.48 [1.34, 1.63]), male (1.38 [1.14,1.68]), and had severe obstructive sleep apnea (1.76 [1.28, 2.43]) were more likely to have short sleep. Antidepressant use was associated with lower odds of short sleep (0.77 [0.59,1.00]). Older age (per 10 years: 1.48 [1.34, 1.62]), male sex (1.34 [1.07,1.68]), and severe obstructive sleep apnea (2.16 [1.47, 3.21]) were associated with higher odds of poor SE. We describe TST and SE from a single sleep center cohort. Multiple demographic characteristics were associated with poor objective sleep in patients during laboratory-based polysomnography. Harrison EI, Roth RH, Lobo JM, et al. Sleep time and efficiency in patients undergoing laboratory-based polysomnography. J Clin Sleep Med. 2021;17(8):1591-1598.

Late Night Thoughts on Listening to Schoenberg’s Klavierstück, op. 33a

This essay considers the sound of Arnold Schoenberg’s Klavierstück, op. 33a, discussing aesthetic effects of combinatoriality and pitch repetition. In taking John Rahn’s general advice regarding listening to Schoenberg “late at night with the lights off,” two compelling parallels with psycholinguistic phenomena emerge—one dealing with semantic satiation, and the other with a related experience called the verbal transformation effect.

Implementation of Internet of Thing Technology for Infrared Therapy Device Design

This study aims to develop an infrared therapy device by embedding the internet of things technology in the research area of therapy devices, especially infrared therapy. Low back pain is a disease that attacks the back muscles that can cause disability and discomfort in activities. This system was developed with an automatic system located in the automation of the lights off and the LM35 temperature sensor, which records the temperature if you feel hot and the timer setting that appears on the LCD and the android interface. This system is based on the internet of things to be monitored from anywhere, anytime. This study consists of an LED lamp, cloud system, and ATmega 328 microcontroller. The study and literature review are carried out following the device development method that embeds the internet of things technology systems in infrared. This study’s result is a prototype design of an infrared therapy device with the internet of things technology that can be used to treat people with low back pain.