Time of day influences cytokine and clock gene response to immune stimulation in equine whole blood

Kisspeptin is crucial for the generation of the circadian-gated preovulatory gonadotrophin-releasing hormone (GnRH)–LH surge in female rodents, with expression in the anteroventral periventricular nucleus (AVPV) peaking in the late afternoon of pro-oestrus. Given kisspeptin expression is established before puberty, the aim of the present study was to investigate kisspeptin and clock gene rhythms during the neonatal period. Anterior and posterior hypothalami were collected from C57BL/6J mice on Postnatal Days (P) 5, 15 and 25, at six time points across 24 h, for analysis of gene expression by reverse transcription–quantitative polymerase chain reaction. Expression of aryl hydrocarbon receptor nuclear translocator-like gene (Bmal1) and nuclear receptor subfamily 1, group D, member 2 (Rev-erbα) in the anterior hypothalamus (containing the suprachiasmatic nucleus) was not rhythmic at P5 or P15, but Bmal1 expression exhibited rhythmicity in P25 females, whereas Rev-erbα expression was rhythmic in P25 males. KiSS-1 metastasis-suppressor (Kiss1) expression did not exhibit time-of-day variation in the anterior (containing the AVPV) or posterior (containing the arcuate nucleus) hypothalami in female and male mice at P5, P15 or P25. The data indicate that the kisspeptin circadian peak in expression observed in the AVPV of pro-oestrous females does not manifest at P5, P15 or P25, likely due to inadequate oestrogenic stimuli, as well as incomplete development of clock gene rhythmicity before puberty.

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FinDonor 10 000 study: A cohort to identify iron depletion and factors affecting it in Finnish blood donors

10.1101/507665 ◽

2018 ◽

Cited By ~ 1

Author(s):

Jukka Partanen ◽

Pia Niittymäki ◽

Nina Nikiforow ◽

Elina Palokangas ◽

Muriel Lobier ◽

...

Keyword(s):

Whole Blood ◽

Blood Donors ◽

Iron Status ◽

Time Lag ◽

Time Of Day ◽

Cool Temperature ◽

Factors Affecting ◽

Iron Stores ◽

Increased Risk ◽

Donation Frequency

AbstractBackground and ObjectivesThere is increasing evidence that frequent blood donation depletes the iron stores of some blood donors. The FinDonor 10 000 study was set up to study iron status and factors affecting iron stores in Finnish blood donors. In Finland, iron supplementation for at-risk groups has been in place since the 1980’s.Material and Methods2584 blood donors (N= 8003 samples) were recruited into the study alongside the standard donation at three donation sites in the capital region of Finland between 5/2015 and 12/2017. All participants were asked to fill out a questionnaire about their health and lifestyle. Blood samples were collected from the sample pouch of whole blood collection set, kept in cool temperature and processed centrally. Whole blood count, CRP, ferritin and sTFR were measured from the samples and DNA was isolated for GWAS studies.ResultsParticipant demographics, albeit in general similar to the general blood donor population in Finland, indicated some bias toward older and more frequent donors. Participation in the study increased median donation frequency of the donors. Analysis of the effect of time lag from the sampling to the analysis and the time of day when sample was drawn revealed small but significant time-dependent changes.ConclusionThe FinDonor cohort now provides us with tools to identify potential donor groups at increased risk of iron deficiency as factors explaining this risk. The increase in donation frequency during the study suggests that scientific projects can be used to increase the commitment of blood donors.

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Abstract P639: Attenuation of Renal Inner Medullary Circadian Clock Gene Expression in Response to High Salt Intake is Dependent on the Endothelin B Receptor

Hypertension ◽

10.1161/hyp.66.suppl_1.p639 ◽

2015 ◽

Vol 66 (suppl_1) ◽

Author(s):

Joshua S Speed ◽

Kelly A Hyndman ◽

Malgorzata Kasztan ◽

Jermaine G Johnston ◽

Martin E Young ◽

...

Keyword(s):

Gene Expression ◽

Circadian Clock ◽

Clock Gene ◽

Salt Intake ◽

Time Of Day ◽

High Salt ◽

Circadian Clock Gene ◽

Clock Gene Expression ◽

High Salt Intake ◽

Renal Inner Medulla

Our lab has recently shown that ETB deficient (ETB def) rats have a time of day dependent impairment in their ability to excrete a Na+ load. These observations suggest an interaction between renal ETB receptors and circadian mechanisms that regulate renal tubular Na+ transport and excretion. Given that knockout of the circadian clock gene Bmal1 reduces blood pressure in mice, we hypothesized that a high salt intake impairs the clock mechanism in the renal inner medulla in an ETB dependent manner. Transgenic control (Tg con) or ETB def rats were fed normal (NS, 0.8% NaCl) or high (HS, 4% NaCl) salt for two weeks. In one group, rats were euthanized every 4 hours beginning at zeitgeber time 0 (lights on) for tissue collection (and subsequent assessment of circadian clock genes), while in a second group of rats urine was collected in 12-hour intervals (active vs. inactive). Consistent with our hypothesis, we observed that HS abolished the normal oscillation in Bmal1 expression in the renal inner medulla of Tg con rats, and effect not observed in ETB def rats. Interestingly, renal production of ET-1, was significantly higher during the active period vs. inactive period in both NS (3.6±1.1 vs. 0.8±0.2 pg/12hr respectively) and HS (9.2±4.1 vs. 1.6±0.3 pg/12hr respectively) fed Tg con rats. There was no time-of-day-dependent difference in ET-1 excretion in ETB def rats on NS (6.6±2.2 vs. 4.6±1.7 pg/12hr respectively), although this pattern was restored in ETB def rats fed HS (2.2±1.0 vs. 9.2±2.5 pg/12hr inactive vs. active). Taken together, these data indicate that an increase in renal ET-1/ETB activation in response to HS modulates inner medullary clock gene expression to promote renal Na+ excretion.

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Diurnal Corticosterone Presence and Phase Modulate Clock Gene Expression in the Male Rat Prefrontal Cortex

Endocrinology ◽

10.1210/en.2015-1884 ◽

2016 ◽

Vol 157 (4) ◽

pp. 1522-1534 ◽

Cited By ~ 17

Author(s):

Elizabeth R. Woodruff ◽

Lauren E. Chun ◽

Laura R. Hinds ◽

Robert L. Spencer

Keyword(s):

Gene Expression ◽

Prefrontal Cortex ◽

Clock Gene ◽

Expression Patterns ◽

Time Of Day ◽

Male Rat ◽

Mrna Levels ◽

Diurnal Pattern ◽

Peripheral Tissues ◽

Clock Gene Expression

Abstract Mood disorders are associated with dysregulation of prefrontal cortex (PFC) function, circadian rhythms, and diurnal glucocorticoid (corticosterone [CORT]) circulation. Entrainment of clock gene expression in some peripheral tissues depends on CORT. In this study, we characterized over the course of the day the mRNA expression pattern of the core clock genes Per1, Per2, and Bmal1 in the male rat PFC and suprachiasmatic nucleus (SCN) under different diurnal CORT conditions. In experiment 1, rats were left adrenal-intact (sham) or were adrenalectomized (ADX) followed by 10 daily antiphasic (opposite time of day of the endogenous CORT peak) ip injections of either vehicle or 2.5 mg/kg CORT. In experiment 2, all rats received ADX surgery followed by 13 daily injections of vehicle or CORT either antiphasic or in-phase with the endogenous CORT peak. In sham rats clock gene mRNA levels displayed a diurnal pattern of expression in the PFC and the SCN, but the phase differed between the 2 structures. ADX substantially altered clock gene expression patterns in the PFC. This alteration was normalized by in-phase CORT treatment, whereas antiphasic CORT treatment appears to have eliminated a diurnal pattern (Per1 and Bmal1) or dampened/inverted its phase (Per2). There was very little effect of CORT condition on clock gene expression in the SCN. These experiments suggest that an important component of glucocorticoid circadian physiology entails CORT regulation of the molecular clock in the PFC. Consequently, they also point to a possible mechanism that contributes to PFC disrupted function in disorders associated with abnormal CORT circulation.

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Evidence for widespread dysregulation of circadian clock progression in human cancer

PeerJ ◽

10.7717/peerj.4327 ◽

2018 ◽

Vol 6 ◽

pp. e4327 ◽

Cited By ~ 20

Author(s):

Jarrod Shilts ◽

Guanhua Chen ◽

Jacob J. Hughey

Keyword(s):

Circadian Clock ◽

Clock Gene ◽

Clock Genes ◽

Human Cancer ◽

Human Tumor ◽

Time Of Day ◽

Large Set ◽

Healthy Human ◽

Promote Tumor Growth

The ubiquitous daily rhythms in mammalian physiology are guided by progression of the circadian clock. In mice, systemic disruption of the clock can promote tumor growth. In vitro, multiple oncogenes can disrupt the clock. However, due to the difficulties of studying circadian rhythms in solid tissues in humans, whether the clock is disrupted within human tumors has remained unknown. We sought to determine the state of the circadian clock in human cancer using publicly available transcriptome data. We developed a method, called the clock correlation distance (CCD), to infer circadian clock progression in a group of samples based on the co-expression of 12 clock genes. Our method can be applied to modestly sized datasets in which samples are not labeled with time of day and coverage of the circadian cycle is incomplete. We used the method to define a signature of clock gene co-expression in healthy mouse organs, then validated the signature in healthy human tissues. By then comparing human tumor and non-tumor samples from twenty datasets of a range of cancer types, we discovered that clock gene co-expression in tumors is consistently perturbed. Subsequent analysis of data from clock gene knockouts in mice suggested that perturbed clock gene co-expression in human cancer is not caused solely by the inactivation of clock genes. Furthermore, focusing on lung cancer, we found that human lung tumors showed systematic changes in expression in a large set of genes previously inferred to be rhythmic in healthy lung. Our findings suggest that clock progression is dysregulated in many solid human cancers and that this dysregulation could have broad effects on circadian physiology within tumors. In addition, our approach opens the door to using publicly available data to infer circadian clock progression in a multitude of human phenotypes.

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Glucocorticoids reset circadian clock in choroid plexus via period genes

Journal of Endocrinology ◽

10.1530/joe-20-0526 ◽

2020 ◽

Author(s):

Karolína Liška ◽

Martin Sládek ◽

Vendula Čečmanová ◽

Alena Sumová

Keyword(s):

Cerebrospinal Fluid ◽

Choroid Plexus ◽

Glucocorticoid Receptors ◽

Clock Gene ◽

Time Of Day ◽

The Body ◽

Surgical Removal ◽

The Brain

The epithelial cells of choroid plexus (CP) in brain ventricles produce cerebrospinal fluid and act as the blood-cerebrospinal fluid barrier. In this study, we confirmed that CP in the 4th ventricle is composed of cellular oscillators that all harbor glucocorticoid receptors and are mutually synchronized to produce a robust clock gene expression rhythm detectable at the tissue level in vivo and in vitro. Animals lacking glucocorticoids (GCs) due to surgical removal of adrenal glands had Per1, Per2, Nr1d1 and Bmal1 clock gene rhythmicity in their CP significantly dampened, whereas subjecting them to daily bouts of synthetic GC analog, dexamethasone (DEX), reinforced those rhythms. We verified these in vivo effects using an in vitro model of organotypic CP explants; depending on time of its application, DEX significantly increased the amplitude and efficiently reset the phase of the CP clock. The results are the first description of a PRC for a non-neuronal clock in the brain, demonstrating that CP clock shares some properties with the non-neuronal clocks elsewhere in the body. Finally, we found that DEX exhibited multiple synergic effects on the CP clock, including acute activation of Per1 expression and change of PER2 protein turnover rate. The DEX-induced shifts of the CP clock were partially mediated via PKA-ERK1/2 pathway. The results provide first evidence that the GC rhythm strengthens and entrains the clock in the CP helping thus fine-tune the brain environment according to time of day.

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Circadian rhythms in septic shock patients

Annals of Intensive Care ◽

10.1186/s13613-021-00833-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Gunnar Lachmann ◽

Bharath Ananthasubramaniam ◽

Viktor A. Wünsch ◽

Lara-Marie Scherfig ◽

Clarissa von Haefen ◽

...

Keyword(s):

Gene Expression ◽

Septic Shock ◽

Immune Cells ◽

Clock Gene ◽

Clock Genes ◽

Young Men ◽

Time Of Day ◽

Organ Injury ◽

Control Group ◽

Clock Gene Expression

Abstract Background Despite the intensive efforts to improve the diagnosis and therapy of sepsis over the last decade, the mortality of septic shock remains high and causes substantial socioeconomical burden of disease. The function of immune cells is time-of-day-dependent and is regulated by several circadian clock genes. This study aims to investigate whether the rhythmicity of clock gene expression is altered in patients with septic shock. Methods This prospective pilot study was performed at the university hospital Charité–Universitätsmedizin Berlin, Department of Anesthesiology and Operative Intensive Care Medicine (CCM, CVK). We included 20 patients with septic shock between May 2014 and January 2018, from whom blood was drawn every 4 h over a 24-h period to isolate CD14-positive monocytes and to measure the expression of 17 clock and clock-associated genes. Of these patients, 3 whose samples expressed fewer than 8 clock genes were excluded from the final analysis. A rhythmicity score SP was calculated, which comprises values between -1 (arrhythmic) and 1 (rhythmic), and expression data were compared to data of a healthy study population additionally. Results 77% of the measured clock genes showed inconclusive rhythms, i.e., neither rhythmic nor arrhythmic. The clock genes NR1D1, NR1D2 and CRY2 were the most rhythmic, while CLOCK and ARNTL were the least rhythmic. Overall, the rhythmicity scores for septic shock patients were significantly (p < 0.0001) lower (0.23 ± 0.26) compared to the control group (12 healthy young men, 0.70 ± 0.18). In addition, the expression of clock genes CRY1, NR1D1, NR1D2, DBP, and PER2 was suppressed in septic shock patients and CRY2 was significantly upregulated compared to controls. Conclusion Molecular rhythms in immune cells of septic shock patients were substantially altered and decreased compared to healthy young men. The decrease in rhythmicity was clock gene-dependent. The loss of rhythmicity and down-regulation of clock gene expression might be caused by sepsis and might further deteriorate immune responses and organ injury, but further studies are necessary to understand underlying pathophysiological mechanisms. Trail registration Clinical trial registered with www.ClinicalTrials.gov (NCT02044575) on 24 January 2014.

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Profile of whole blood gene expression following immune stimulation in a wild passerine

BMC Genomics ◽

10.1186/1471-2164-15-533 ◽

2014 ◽

Vol 15 (1) ◽

pp. 533 ◽

Cited By ~ 12

Author(s):

Richard Meitern ◽

Reidar Andreson ◽

Peeter Hõrak

Keyword(s):

Gene Expression ◽

Whole Blood ◽

Immune Stimulation ◽

Blood Gene Expression

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Clock Gene Expression in the Human Pituitary Gland

Endocrinology ◽

10.1210/en.2012-2274 ◽

2013 ◽

Vol 154 (6) ◽

pp. 2046-2057 ◽

Cited By ~ 13

Author(s):

Florian Wunderer ◽

Sina Kühne ◽

Antje Jilg ◽

Katrin Ackermann ◽

Tamas Sebesteny ◽

...

Keyword(s):

Gene Expression ◽

Clock Gene ◽

Clock Genes ◽

Time Of Day ◽

Adaptive Plasticity ◽

Pituitary Cells ◽

Human Pituitary ◽

Hormone Synthesis ◽

Clock Gene Expression ◽

Pituitary Glands

Abstract Pituitary function relies on strictly timed, yet plastic mechanisms, particularly with respect to the daytime-dependent coordination of hormone synthesis and release. In other systems, clock genes and their protein products are well-described candidates to anticipate the daily demands in neuroendocrine coupling and to manage cellular adaptation on changing internal or external circumstances. To elucidate possible mechanisms of time management, a total of 52 human autoptic pituitary glands were allocated to the 4 time-of-day groups, night, dawn, day, and dusk, according to reported time of death. The observed daytime-dependent dynamics in ACTH content supports a postmortem conservation of the premortem condition, and thus, principally validates the investigation of autoptic pituitary glands. Pituitary extracts were investigated for expression of clock genes Per1, Cry1, Clock, and Bmal1 and corresponding protein products. Only the clock gene Per1 showed daytime-dependent differences in quantitative real-time PCR analyses, with decreased levels observed during dusk. Although the overall amount in clock gene protein products PER1, CRY1, and CLOCK did not fluctuate with time of day in human pituitary, an indication for a temporally parallel intracellular translocation of PER1 and CRY1 was detected by immunofluorescence. Presented data suggest that the observed clock gene expression in human pituitary cells does not provide evidence for a functional intrinsic clockwork. It is suggested that clock genes and their protein products may be directly involved in the daytime-dependent regulation and adaptation of hormone synthesis and release and within homeostatic adaptive plasticity.

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Circadian Rhythms in Septic Shock Patients

10.21203/rs.3.rs-61571/v1 ◽

2020 ◽

Author(s):

Gunnar Lachmann ◽

Bharath Ananthasubramaniam ◽

Viktor A. Wünsch ◽

Lara-Marie Scherfig ◽

Clarissa von Haefen ◽

...

Keyword(s):

Gene Expression ◽

Septic Shock ◽

Immune Cells ◽

Clock Gene ◽

Clock Genes ◽

Time Of Day ◽

University Hospital ◽

Organ Injury ◽

Control Group ◽

Clock Gene Expression

Abstract Background: Although intensive efforts to improve diagnosis and therapy of sepsis over the last decade, the mortality of septic shock remains high and causes substantial socioeconomical burden of disease. The function of immune cells is time-of-day-dependent and is regulated by several circadian clock genes. This study aims to investigate whether the rhythmicity of clock gene expression is altered in patients with septic shock.Methods: This prospective pilot study was performed at the university hospital Charité – Universitätsmedizin Berlin, Department of Anesthesiology and Operative Intensive Care Medicine (CCM, CVK). We included 20 patients with septic shock between May 2014 and January 2018, from whom blood was drawn every 4 hours over a 24-hour period to isolate CD14-positive monocytes and to measure expression of 17 clock and clock-associated genes. Of these patients, 3 whose samples expressed fewer than 8 clock genes were excluded from the final analysis. Expression data were compared to data of a healthy study population and a rhythmicity score SP was calculated, which comprises values between -1 (arrhythmic) and 1 (rhythmic). Results: Overall, the rhythmicity scores for septic shock patients were significantly (p < 0.0001) lower (0.23 ± 0.26) compared to the control group (12 healthy young men, 0.70 ± 0.18). 77% of the measured clock genes were classified as having inconclusive rhythms, i.e. neither rhythmic nor arrhythmic. The clock genes NR1D1, NR1D2 and CRY2 were the most rhythmic, while CLOCK and ARNTL were the least rhythmic. In addition, the expression of clock genes CRY1, NR1D1, NR1D2, DBP, and PER2 was suppressed in septic shock patients and CRY2 was significantly upregulated compared to controls.Conclusion: Compared to young healthy men, molecular rhythms in immune cells of septic shock patients were substantially decreased. The decrease in rhythmicity was clock gene-dependent. The loss of rhythmicity and downregulation of clock gene expression might be caused by sepsis and might further deteriorate immune responses and organ injury, but further studies are necessary to understand underlying pathophysiological mechanisms.Clinical trial registered with www.ClinicalTrials.gov (NCT02044575) on 24 January 2014.

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