Palmitate alters the rhythmic expression of molecular clock genes and orexigenic neuropeptide Y mRNA levels within immortalized, hypothalamic neurons

2011 ◽  
Vol 413 (3) ◽  
pp. 414-419 ◽  
Author(s):  
Laura J. Fick ◽  
Gordon H. Fick ◽  
Denise D. Belsham
Keyword(s):  
Neuropeptide Y ◽  
Molecular Clock ◽  
Clock Genes ◽  
Mrna Levels ◽  
Hypothalamic Neurons ◽  
Rhythmic Expression

P–372 Maternal circadian disruption is associated with impaired rhythmic expression of molecular clock genes and IUGR during placenta development in mice

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
N I Bektas ◽  
G Akcay ◽  
N Derin ◽  
D Adiguzel ◽  
C Celik-Ozenci
Keyword(s):  
Circadian Rhythm ◽  
Locomotor Activity ◽  
Molecular Clock ◽  
Clock Genes ◽  
Weight Ratio ◽  
Circadian Disruption ◽  
Control Group ◽  
Shift Workers ◽  
Rhythmic Expression ◽  
Registration Number

Abstract Study question Are molecular clock genes (MCGs) expressed rhythmically in mouse placenta, and whether maternal circadian rhythm disruption (MCRD) is associated with intrauterine growth retardation (IUGR) through disturbing rhythmic expression of MCGs? Summary answer Maternal circadian disruption causes impaired rhythmic expression of MCGs (Bmal1, Clock, Npas2, Per1, Per2, Per3, Cry1, and Cry2) and IUGR during placenta development in mice. What is known already The world economy is based on a 24/7 society and shift work or jet travel across time zones disrupts circadian rhythm in pregnant women. Evidence indicates that gestational chrono-disruption results in IUGR. Mature mouse and human placenta express MCGs. There is no information in the literature on whether the MCG expression in the placenta is rhythmic or not and whether the rhythmic expression of MCGs is impaired due to MCRD during pregnancy. Also, it is not known whether the association with MCRD and IUGR is related to MCGs. Study design, size, duration Young adult female BALB/c mice were paired with males until vaginal plug formation was verified. Females were randomly assigned to two groups: control and phase-advance. Controls remained on a constant 12-hr light:12-hr dark cycle, whereas phase-advanced mice were subjected to 6-hr advances in the LD cycle every 5 days. Placentae (n = 1329) and fetuses were obtained from 144 mice at Zeitgeber time (ZT)0, ZT6, ZT12, and ZT18 days 12, 14, and 16 of pregnancy. Participants/materials, setting, methods The following analysis was performed: (i) open field test was used for locomotor activity evaluations to confirm MCRD, (ii) placenta/fetus weight ratio for evaluation of IUGR development, (iii) morphometric evaluation of placental compartments utilizing H&E staining (iv) gene expression analysis of MCGs utilizing qRT-PCR. One-way and Two-way ANOVA test followed by Holm-Sidak posthoc test was used for multiple comparisons. Values are expressed as mean ± standard error, and values below p < 0.05 were considered statistically significant. Main results and the role of chance Expression of MCGs (Bmal1, Clock, Npas2, Per1, Per2, Per3, Cry1, and Cry2) was rhythmic in the early and mature placenta development stages (days 12, 14, 16). Locomotor activity tests reveal that the total distance covered on the 16th day of pregnancy significantly decreased compared to the control group (p = 0.000158). The ratio of the time spent in the outer/inner quadrant, an anxiety indicator, significantly increased in the MCRD group on the 14th (p = 0.0351) and 16th days of pregnancy (p = 0.000329). While the number of fetuses was similar in both groups for all gestational days (p = 0.896), in the MCRD group, the fetus/placenta weight ratio decreased significantly on the 12th and 16th days of pregnancy (p < 0.001). Thus, IUGR developed due to MCRD. Histomorphometry analysis of the placental compartments revealed a significant reduction in the spongiotrophoblast layer’s size on all days of pregnancy and the labyrinth layer on day 16 (p < 0.05). Finally, the rhythmic expression MCGs were impaired in placentas obtained from MCRD groups on days 12th, 14th, 6th of pregnancy (p < 0.001). In conclusion, we found a robust relationship with the disturbed MCGs expression and occurrence of IUGR during a chrono-disrupted gestation. Limitations, reasons for caution Since this study was conducted in mice, care should be taken when translating the results to humans. Wider implications of the findings: Our results in mice are important for initiating basic science knowledge regarding the outcomes of maternal chrono-disruption. Moreover, research in the placenta of gestational chrono-disrupted mothers, such as shift-workers, are urgently needed to translate our findings into the clinic. Trial registration number TUBITAK–119S121 and Akdeniz University Research Projects Unit TYL–2018–3960

scholarly journals Clock gene expression in gravid uterus and extra-embryonic tissues during late gestation in the mouse

2010 ◽  
Vol 22 (5) ◽  
pp. 743 ◽  
Author(s):  
Christine K. Ratajczak ◽  
Erik D. Herzog ◽  
Louis J. Muglia
Keyword(s):  
Molecular Clock ◽  
Clock Genes ◽  
Circadian Rhythmicity ◽  
Late Gestation ◽  
Gravid Uterus ◽  
Fetal Membranes ◽  
Molecular Clocks ◽  
Potential Contribution ◽  
Rhythmic Expression ◽  
Clock Gene Expression

Evidence in humans and rodents suggests the importance of circadian rhythmicity in parturition. A molecular clock underlies the generation of circadian rhythmicity. While this molecular clock has been identified in numerous tissues, the expression and regulation of clock genes in tissues relevant to parturition is largely undefined. Here, the expression and regulation of the clock genes Bmal1, Clock, cryptochrome (Cry1/2) and period (Per1/2) was examined in the murine gravid uterus, placenta and fetal membranes during late gestation. All clock genes examined were expressed in the tissues of interest throughout the last third of gestation. Upregulation of a subset of these clock genes was observed in each of these tissues in the final two days of gestation. Oscillating expression of mRNA for a subset of the examined clock genes was detected in the gravid uterus, placenta and fetal membranes. Furthermore, bioluminescence recording on explants from gravid Per2::luciferase mice indicated rhythmic expression of PER2 protein in these tissues. These data demonstrate expression and rhythmicity of clock genes in tissues relevant to parturition indicating a potential contribution of peripheral molecular clocks to this process.

scholarly journals The vascular clock: a new insight into endothelial cells and pericytes crosstalk

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
V Mastrullo ◽  
R S Matos ◽  
J H McVey ◽  
P Gupta ◽  
P Madeddu ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Circadian Rhythms ◽  
Circadian Clock ◽  
Blood Vessels ◽  
Molecular Clock ◽  
Clock Genes ◽  
Public Institution ◽  
Perivascular Cells ◽  
Rhythmic Expression ◽  
The Impact

Abstract Background/Introduction Circadian rhythms, defined as biological oscillations with a period of circa 24h, regulate many physiological processes in the cardiovascular system, such as vascular function, vascular tone, blood pressure, heart rate and thrombus formation [1]. The vasculature responds to the main pacemaker located in the brain, but it also possesses its own clock. Indeed, a molecular clock has been identified in endothelial cells (EC) and smooth muscle cells (SMC). The disruption of the circadian clock profoundly affects cardiovascular functionality with adverse cardiovascular events such as myocardial infarction or stroke showing a 24h rhythmicity with a peak incidence in the early morning. Among several mechanisms affected by circadian dysregulation, angiogenesis plays a fundamental role in homeostasis and development of new blood vessels. EC and pericytes (PC) are the two main cell populations in the capillaries, and their physical and paracrine interaction drives and regulates the sprouting. However, the presence and the role of circadian rhythms in pericytes and whether the molecular clock affects the endothelial/pericyte interactions remain unexplored. Purpose The aim of this study is to identify a molecular clock in human vascular pericytes and elucidate the impact of the circadian clock on the formation of new blood vessels. Methods Human primary PC were synchronised and the rhythmicity of clock genes measured by luminescence, immunofluorescence, and qPCR. Synchronised PC were co-cultured with Bmal1::LUC human primary EC. The effect of PC synchronisation and circadian clock disruption by shRNA on EC clock genes and angiogenic potential were measured by luminescence and Matrigel assay, respectively. A macroporous polyurethane scaffold was developed for 3D co-cultures. Results PC presented rhythmic expression of the principal circadian genes with a circa 24h period but in our experimental setting, EC did not show circadian rhythmicity. Synchronised PC supported the rhythmic expression of the clock gene Bmal1 in EC in a contact co-culture system, suggesting a secondary form of EC molecular clock regulation. Non-contact co-cultures failed to synchronise EC. Furthermore, when the clock was disrupted in PC, their capacity to support EC's tube-forming capacity on Matrigel was impaired; clock disruption in EC did not affect angiogenesis, supporting the hypothesis that a disrupted clock in perivascular cells affects angiogenesis. In a 3D tissue engineering scaffold seeded with both EC and PC, the synchronisation of the clock led to the development of organised vascular-like structures around the scaffold's pores, as compared to the non-synchronised condition where cells appeared disorganised. Conclusion This study defines for the first time the existence of an endogenous molecular circadian clock in perivascular cells and suggests implications for circadian clock synchronisation in physiological and therapeutic angiogenesis. FUNDunding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): University of Surrey Doctoral CollegeUniversity of Surrey Bioprocess and Biochemical Engineering (BioProChem) Group.

Downregulation of core clock gene Bmal1 attenuates expression of progesterone and prostaglandin biosynthesis-related genes in rat luteinizing granulosa cells

2013 ◽  
Vol 304 (12) ◽  
pp. C1131-C1140 ◽  
Author(s):  
Huatao Chen ◽  
Lijia Zhao ◽  
Makoto Kumazawa ◽  
Nobuhiko Yamauchi ◽  
Yasufumi Shigeyoshi ◽  
...  
Keyword(s):  
Granulosa Cells ◽  
Clock Genes ◽  
Prostaglandin E ◽  
Mrna Levels ◽  
Rhythmic Expression ◽  
Circadian Oscillators ◽  
Transcript Profiles ◽  
Si Rna ◽  
Reproductive Processes ◽  
Core Clock Gene

Ovarian circadian oscillators have been implicated in the reproductive processes of mammals. However, there are few reports regarding the detection of ovarian clock-controlled genes (CCGs). The present study was designed to unravel the mechanisms through which CCG ovarian circadian oscillators regulate fertility, primarily using quantitative RT-PCR and RNA interference against Bmal1 in rat granulosa cells. Mature granulosa cells were prepared from mouse Per2-destabilized luciferase ( dLuc) reporter gene transgenic rats. A real-time monitoring system of Per2 promoter activity was employed to detect Per2-dLuc oscillations. The cells exposed to luteinizing hormone (LH) displayed clear Per2-dLuc oscillations and a rhythmic expression of clock genes ( Bmal1, Per1, Per2, Rev-erbα, and Dbp). Meanwhile, the examined ovarian genes ( Star, Cyp19a1, Cyp11a1, Ptgs2, Lhcgr, and p53) showed rhythmic transcript profiles except for Hsd3b2, indicating that these rhythmic expression genes may be CCGs. Notably, Bmal1 small interfering (si)RNA treatment significantly decreased both the amplitude of Per2-dLuc oscillations and Bmal1 mRNA levels compared with nonsilencing RNA treatment in luteinizing granulosa cells. Depletion of Bmal1 by siRNA decreased the transcript levels of clock genes ( Per1, Per2, Rev-erbα, and Dbp) and examined ovarian genes ( Star, Cyp19a1, Cyp11a1, Ptgs2, Hsd3b2, and Lhcgr). Accordingly, knockdown of Bmal1 also inhibited the synthesis of progesterone and prostaglandin E2, which are associated with crucial reproductive processes. Collectively, these data suggest that ovarian circadian oscillators regulate the synthesis of steroid hormones and prostaglandins through ovarian-specific CCGs in response to LH stimuli. The present study provides new insights into the physiologic significance of Bmal1 related to fertility in ovarian circadian oscillators.

scholarly journals The role of clockwork orange in the circadian clock of the cricket Gryllus bimaculatus

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Yasuaki Tomiyama ◽  
Tsugumichi Shinohara ◽  
Mirai Matsuka ◽  
Tetsuya Bando ◽  
Taro Mito ◽  
...  
Keyword(s):  
Circadian Clock ◽  
Clock Genes ◽  
Clock Cycle ◽  
Constant Darkness ◽  
Mrna Levels ◽  
Gryllus Bimaculatus ◽  
Locomotor Rhythm ◽  
Rhythmic Expression ◽  
Cryptochrome 2

Abstract The circadian clock generates rhythms of approximately 24 h through periodic expression of the clock genes. In insects, the major clock genes period (per) and timeless (tim) are rhythmically expressed upon their transactivation by CLOCK/CYCLE, with peak levels in the early night. In Drosophila, clockwork orange (cwo) is known to inhibit the transcription of per and tim during the daytime to enhance the amplitude of the rhythm, but its function in other insects is largely unknown. In this study, we investigated the role of cwo in the clock mechanism of the cricket Gryllus bimaculatus. The results of quantitative RT-PCR showed that under a light/dark (LD) cycle, cwo is rhythmically expressed in the optic lobe (lamina-medulla complex) and peaks during the night. When cwo was knocked down via RNA interference (RNAi), some crickets lost their locomotor rhythm, while others maintained a rhythm but exhibited a longer free-running period under constant darkness (DD). In cwoRNAi crickets, all clock genes except for cryptochrome 2 (cry2) showed arrhythmic expression under DD; under LD, some of the clock genes showed higher mRNA levels, and tim showed rhythmic expression with a delayed phase. Based on these results, we propose that cwo plays an important role in the cricket circadian clock.

FSH induces the development of circadian clockwork in rat granulosa cells via a gap junction protein Cx43-dependent pathway

2013 ◽  
Vol 304 (6) ◽  
pp. E566-E575 ◽  
Author(s):  
Huatao Chen ◽  
Lijia Zhao ◽  
Guiyan Chu ◽  
Gakushi Kito ◽  
Nobuhiko Yamauchi ◽  
...  
Keyword(s):  
Gap Junction ◽  
Granulosa Cells ◽  
Clock Genes ◽  
Fluorescence Signal ◽  
Mrna Levels ◽  
Rhythmic Expression ◽  
Clock System ◽  
Junction Protein ◽  
Equine Chorionic Gonadotropin ◽  
Cx 43

The present study was designed to assess the relationship between gap junctions and the maturation of a clock system in rat granulosa cells stimulated by follicle-stimulating hormone (FSH). Immature and mature granulosa cells were prepared by puncturing the ovaries of diethylstilbestrol- and equine chorionic gonadotropin (eCG)-treated mouse Period2 ( Per2)- dLuc reporter gene transgenic rats, respectively. Mature granulosa cells exposed to dexamethasone (DXM) synchronization displayed several Per2-dLuc oscillations and a rhythmic expression of clock genes. Intriguingly, we observed clear evidence that the FSH stimulation significantly increased the amplitude of Per2 oscillations in the granulosa cells, which was confirmed by the elevation of the Per2 and Rev-erbα ( Nr1d1) mRNA levels. FSH also induced a major phase-advance shift of Per2 oscillations. The mature granulosa cells cultured for 2 days with FSH expressed higher mRNA levels of Per2, Rev-erbα, Bmal1 ( Arnt1), Lhcgr, and connexin ( Cx) 43 ( Gja1) compared with the immature granulosa cells. Consistently, our immunofluorescence results revealed abundant Cx43 protein in antral follicles stimulated with eCG and weak or no fluorescence signal of Cx43 in primary and preantral follicles. Similar results were confirmed by Western blotting analysis. Two gap junction blockers, lindane and carbenoxolone (CBX), significantly decreased the amplitude of Per2 oscillations, which further adhered significant decreases in Per2 and Rev-erbα transcript levels. In addition, both lindane and CBX induced a clear phase-delay shift of Per2 oscillations. These findings suggest that FSH induces the development of the clock system by increasing the expression of Cx43.

scholarly journals DBC1 (Deleted in Breast Cancer 1) modulates the stability and function of the nuclear receptor Rev-erbα

2013 ◽  
Vol 451 (3) ◽  
pp. 453-461 ◽  
Author(s):  
Claudia C. S. Chini ◽  
Carlos Escande ◽  
Veronica Nin ◽  
Eduardo N. Chini
Keyword(s):  
Breast Cancer ◽  
Nuclear Receptor ◽  
Clock Genes ◽  
Mrna Levels ◽  
Protein Levels ◽  
The Stability ◽  
And Function ◽  
Interfering Rna ◽  
In Cells

The nuclear receptor Rev-erbα has been implicated as a major regulator of the circadian clock and integrates circadian rhythm and metabolism. Rev-erbα controls circadian oscillations of several clock genes and Rev-erbα protein degradation is important for maintenance of the circadian oscillations and also for adipocyte differentiation. Elucidating the mechanisms that regulate Rev-erbα stability is essential for our understanding of these processes. In the present paper, we report that the protein DBC1 (Deleted in Breast Cancer 1) is a novel regulator of Rev-erbα. Rev-erbα and DBC1 interact in cells and in vivo, and DBC1 modulates the Rev-erbα repressor function. Depletion of DBC1 by siRNA (small interfering RNA) in cells or in DBC1-KO (knockout) mice produced a marked decrease in Rev-erbα protein levels, but not in mRNA levels. In contrast, DBC1 overexpression significantly enhanced Rev-erbα protein stability by preventing its ubiquitination and degradation. The regulation of Rev-erbα protein levels and function by DBC1 depends on both the N-terminal and C-terminal domains of DBC1. More importantly, in cells depleted of DBC1, there was a dramatic decrease in circadian oscillations of both Rev-erbα and BMAL1. In summary, our data identify DBC1 as an important regulator of the circadian receptor Rev-erbα and proposes that Rev-erbα could be involved in mediating some of the physiological effects of DBC1.

In vivo action of a new octadecaneuropeptide antagonist on neuropeptide Y and corticotropin-releasing hormone mRNA levels in rat

2005 ◽  
Vol 141 (2) ◽  
pp. 156-160 ◽  
Author(s):  
V. Compère ◽  
S. Li ◽  
J. Leprince ◽  
M.C. Tonon ◽  
H. Vaudry ◽  
...  
Keyword(s):  
Neuropeptide Y ◽  
Mrna Levels ◽  
Corticotropin Releasing Hormone ◽  
Releasing Hormone

scholarly journals Secretogranin II binds to secretogranin III and forms secretory granules with orexin, neuropeptide Y, and POMC

2009 ◽  
Vol 202 (1) ◽  
pp. 111-121 ◽  
Author(s):  
Kikuko Hotta ◽  
Masahiro Hosaka ◽  
Atsushi Tanabe ◽  
Toshiyuki Takeuchi
Keyword(s):  
Body Weight ◽  
Neuropeptide Y ◽  
Secretory Granules ◽  
Immunohistochemical Analysis ◽  
Mrna Levels ◽  
Weight Changes ◽  
Body Weight Changes ◽  
Hypothalamic Area ◽  
Double Labeling ◽  
Secretogranin Ii

Functional variations in the secretogranin III (SCG3) gene are associated with susceptibility to obesity. SCG3 forms secretory granules with orexin, melanin-concentrating hormone (MCH), neuropeptide Y (NPY), and POMC in the hypothalamus. In this study, we screened proteins for SCG3-binding activity and identified secretogranin II (SCG2) using a yeast two-hybrid system. Immunoprecipitation revealed that SCG2 interacts with SCG3. In situ hybridization and immunohistochemistry indicated that SCG2 was highly expressed in the lateral hypothalamic area, paraventricular nucleus, and arcuate nucleus of the hypothalamus. Double-labeling immunohistochemical analysis demonstrated that SCG2 was expressed in orexin-, MCH-, NPY-, and POMC-expressing neurons. SCG2 was also coexpressed with SCG3. Upon introduction into neuroblastoma cells, SCG2 was expressed in the cytosol and formed granule-like structures with SCG3, orexin, NPY, or POMC. SCG3 bound to POMC; however, it did not bind to orexin, MCH, or NPY. By contrast, SCG2 formed aggregates with orexin, MCH, NPY, and POMC. SCG2 may act as a hormone carrier for orexin, MCH, NPY, and POMC by binding with SCG3, which targets proteins to the secretory granules. SCG2 mRNA levels increased along with those of SCG3, orexin, MCH, and NPY after a 24-h fast, suggesting that the SCG2/SCG3 system may respond in an adaptive manner to acute body weight changes. However, this SCG2/SCG3 system appears to be unresponsive to chronic body weight changes, such as diet-induced obesity or obesity in ob/ob mice. We suggest that SCG2, as well as SCG3, may be a potential regulator of food intake based on its capacity to accumulate appetite-related hormones into secretory granules.

Regulation of food intake by neuropeptide Y in goldfish

2000 ◽  
Vol 279 (3) ◽  
pp. R1025-R1034 ◽  
Author(s):  
Yuwaraj K. Narnaware ◽  
Pierre P. Peyon ◽  
Xinwei Lin ◽  
Richard E. Peter
Keyword(s):  
Food Intake ◽  
Neuropeptide Y ◽  
Mrna Levels ◽  
Food Ration ◽  
Y1 Receptor ◽  
Daily Food ◽  
Daily Food Ration ◽  
Brain Ventricle ◽  
Dose Dependent Increase ◽  
Dose Dependent

In mammals, neuropeptide Y (NPY) is a potent orexigenic factor. In the present study, third brain ventricle (intracerebroventricular) injection of goldfish NPY (gNPY) caused a dose-dependent increase in food intake in goldfish, and intracerebroventricular administration of NPY Y1-receptor antagonist BIBP-3226 decreased food intake; the actions of gNPY were blocked by simultaneous injection of BIBP-3226. Goldfish maintained on a daily scheduled feeding regimen display an increase in NPY mRNA levels in the telencephalon-preoptic area and hypothalamus shortly before feeding; however, a decrease occured in optic tectum-thalamus. In both fed and unfed fish, brain NPY mRNA levels decreased after scheduled feeding. Restriction in daily food ration intake for 1 wk or food deprivation for 72 h resulted in increased brain NPY mRNA levels. Results from these studies demonstrate that NPY is a physiological brain signal involved in feeding behavior in goldfish, mediating its effects, at least in part, through Y1-like receptors in the brain.

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