scholarly journals Circadian rhythms of behavioral cone sensitivity and long wavelength opsin mRNA expression: a correlation study in zebrafish

2005 ◽  
Vol 208 (3) ◽  
pp. 497-504 ◽  
Author(s):  
P. Li
Keyword(s):  
Circadian Rhythms ◽  
Mrna Expression ◽  
Correlation Study ◽  
Long Wavelength ◽  
Cone Sensitivity

scholarly journals Memories of Rhythms Past: Evidence for Hippocampal Core Clock Disruptions in a Murine Model of Western Diet-induced Obesity (OR32-02-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Lauren Woodie ◽  
Robert Johnson ◽  
Bulbul Ahmed ◽  
Michael Greene
Keyword(s):  
Circadian Rhythms ◽  
Mrna Expression ◽  
Tap Water ◽  
Western Diet ◽  
Diurnal Rhythms ◽  
Whole Body ◽  
Molecular Clocks ◽  
Sugar Solution ◽  
Peripheral Tissues ◽  
The Core

Abstract Objectives Mammalian circadian rhythms are dictated by solar signals transmitted to the hypothalamic suprachaismatic nucleus (SCN). Although the SCN is the central clock for circadian rhythms, molecular clocks are found in every cell and are composed of the core clock proteins BMAL1, CLOCK/NPAS2, Period (Per) and Cryptochrome (Cry). Disruptions in the core clock occur in peripheral tissues after Western diet (WD) feeding and contribute to WD-induced metabolic disease. The mammalian center of memory, the hippocampus, is also sensitive to WD-induced dysfunction, but whether the WD disrupts the hippocampal core clock is not known. The present research explores this gap in our knowledge by examining hippocampal core clock rhythmicity in a mouse model of WD-induced obesity. Methods Mice were maintained on either standard rodent chow with tap water or a 45%/kcal fat WD with a 4% sugar solution (WD + S). Diurnal metabolic rhythms were collected for 24 h in metabolic cages during the 16th week of diet exposure. Livers, hypothalami and hippocampi were then collected at 4-h increments over 24 h. mRNA expression was measured using RT-qPCR and assessed by cosinor-based rhythmometry. Results WD + S feeding significantly increased body weight and normalized liver weight (P < 0.001) and significantly dampened diurnal rhythms of whole-body metabolism (P < 0.05). As expected, the WD + S also induced significant alterations in the hepatic rhythmicity of bmal1 and cry1 expression (P < 0.05). In line with previous findings, the rhythm of the hypothalamic core clock did not significantly differ between the dietary groups. The hippocampal core clock, however, was significantly disrupted by the WD + S. Bmal1 and npas2 expression were phase shifted by 16 and 4 h, respectively, while per2 expression was significantly amplified across all measured time points in the WD + S group (P < 0.01). Conclusions WD + S feeding significantly alters the rhythmicity of core clock mRNA expression in the hippocampus. These results indicate that diet-induced disruptions of the core clock may have implications in memory diseases with significant circadian etiologies, such as Alzheimer's disease. Funding Sources Funding was provided by the Alabama Agricultural Experiment Station and the Auburn University Center for Neuroscience Initiative.

A correlation study of Boar taint-related genes, Boar tant substances and sex hormones in Bama miniature pigs at defferent ages

2015 ◽  
Author(s):  
Q. H. Wang ◽  
J. Y. Chen ◽  
K. N. Guo ◽  
X. B. Zheng ◽  
Q. Wu ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Sex Hormones ◽  
Correlation Study ◽  
Boar Taint ◽  
Miniature Pig ◽  
Miniature Pigs ◽  
Meat Flavor ◽  
The Relationship ◽  
Sus Scrofa Domestica

The Bama miniature pig (Sus scrofa domestica), endemic in China,which is characterized by its small size and specific meat flavor. The evaluation of pork quality is closely related to boar taint. However, there are no published studies of boar taint in Bama miniature pigs. In this study, the correlation between mRNA expression of boar taint-related genes,boar taint substances (androstenone and skatole) and sex hormones (testosterone, estradiol) of Bama miniature pigs at consecutive ages were examined. We found a gradual increase of mRNA (CYP2E1, CYP2A19, CYP2C34, and COUP-TF1) expression in the livers of pigs aged from birth to 6 months of age. The mRNA expression of COUP-TF1 and CYP2C34 peaked at 12 months old. However, the mRNA expression of CYP2E1 and CYP2A19 declined after 6 months age. The mRNA expression of CYP11A1, CYP17A1, StAR, and COUP-TF1 was stable over time in the testicle of Bama miniature pig. However, a substantial increase in their relative expression levels was observed before sexual maturity. Boar age was positively correlated to sex hormone (testosterone, estradiol) and boar taint substances (androstenone, skatole). There is in vivo gene regulation in boars that controls the relationship between boar taint substances and sex hormones. In addition, CYP11A1, CYP17A1, StAR, and sex hormones (testosterone, estradiol) can be used as markers for low boar taint study. Our study elucidated the correlation of boar taint-related genes,boar taint substances and sex hormones. These results have provided reference for applied research using Bama miniature pigs as a model for livestock production.

scholarly journals CLOCK Is Required for Maintaining the Circadian Rhythms of Opsin mRNA Expression in Photoreceptor Cells

2008 ◽  
Vol 283 (46) ◽  
pp. 31673-31678 ◽  
Author(s):  
Ping Li ◽  
Shyam S. Chaurasia ◽  
Yan Gao ◽  
Aprell L. Carr ◽  
P. Michael Iuvone ◽  
...  
Keyword(s):  
Circadian Rhythms ◽  
Mrna Expression ◽  
Photoreceptor Cells

scholarly journals Does a Red House Affect Rhythms in Mice with a Corrupted Circadian System?

2021 ◽  
Vol 22 (5) ◽  
pp. 2288
Author(s):  
Menekse Öztürk ◽  
Marc Ingenwerth ◽  
Martin Sager ◽  
Charlotte von Gall ◽  
Amira A. H. Ali
Keyword(s):  
Circadian Rhythms ◽  
Neuronal Activity ◽  
Clock Genes ◽  
Plasma Corticosterone ◽  
Cellular Level ◽  
Circadian System ◽  
Targeted Deletion ◽  
Long Wavelength ◽  
And Behavior ◽  
Time Information

The circadian rhythms of body functions in mammals are controlled by the circadian system. The suprachiasmatic nucleus (SCN) in the hypothalamus orchestrates subordinate oscillators. Time information is conveyed from the retina to the SCN to coordinate an organism’s physiology and behavior with the light/dark cycle. At the cellular level, molecular clockwork composed of interlocked transcriptional/translational feedback loops of clock genes drives rhythmic gene expression. Mice with targeted deletion of the essential clock gene Bmal1 (Bmal1−/−) have an impaired light input pathway into the circadian system and show a loss of circadian rhythms. The red house (RH) is an animal welfare measure widely used for rodents as a hiding place. Red plastic provides light at a low irradiance and long wavelength—conditions which affect the circadian system. It is not known yet whether the RH affects rhythmic behavior in mice with a corrupted circadian system. Here, we analyzed whether the RH affects spontaneous locomotor activity in Bmal1−/− mice under standard laboratory light conditions. In addition, mPER1- and p-ERK-immunoreactions, as markers for rhythmic SCN neuronal activity, and day/night plasma corticosterone levels were evaluated. Our findings indicate that application of the RH to Bmal1−/− abolishes rhythmic locomotor behavior and dampens rhythmic SCN neuronal activity. However, RH had no effect on the day/night difference in corticosterone levels.

scholarly journals Binge Alcohol Disrupts Skeletal Muscle Core Molecular Clock Independent of Glucocorticoids

2021 ◽  
Author(s):  
Abigail L Tice ◽  
Joseph A Laudato ◽  
Michael L. Rossetti ◽  
Christopher A Wolff ◽  
Karyn A. Esser ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Circadian Rhythms ◽  
Mrna Expression ◽  
Molecular Clock ◽  
Alcohol Intoxication ◽  
Elevated Serum ◽  
C2c12 Myotubes ◽  
Saline Control ◽  
Serum Corticosterone ◽  
The Core

Circadian rhythms are central to optimal physiological function as disruption contributes to the development of several chronic diseases. Alcohol (EtOH) intoxication disrupts circadian rhythms within liver, brain, and intestines, but it is unknown whether alcohol also disrupts components of the core clock in skeletal muscle. Female C57BL/6Hsd mice were randomized to receive either saline (control) or alcohol (EtOH) (5g/kg) via intraperitoneal injection at the start of the dark cycle (ZT12), and gastrocnemius was collected every 4hr from Control and EtOH treated mice for the next 48hr following isoflurane anesthetization. In addition, metyrapone was administered prior to alcohol intoxication in separate mice to determine whether the alcohol-induced increase in serum corticosterone contributed to circadian gene regulation. Finally, synchronized C2C12 myotubes were treated with alcohol (100mM) to assess the influence of centrally or peripherally mediated effects of alcohol on the muscle clock. Alcohol significantly disrupted mRNA expression of Bmal1, Per1/2, and Cry1/2 in addition to perturbing the circadian pattern of clock-controlled genes, Myod1, Dbp, Tef, and Bhlhe40 (p<0.05) in muscle. Alcohol increased serum corticosterone levels and glucocorticoid target gene, Redd1, in muscle. Metyrapone prevented the EtOH-mediated increase in serum corticosterone but did not normalize the EtOH-induced change in Per1, Cry1 and Cry2 and Myod1 mRNA expression. Core clock gene expression (Bmal, Per1/2, Cry1/2) was not changed following 4, 8, or 12hrs of alcohol treatment on synchronized C2C12 myotubes. Therefore, binge alcohol disrupted genes of the core molecular clock independently of elevated serum corticosterone or direct effects of EtOH on the muscle.

scholarly journals Circadian effects of ionizing radiation on reproductive function and clock genes expression in male mouse

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Fenju Qin ◽  
Ningang Liu ◽  
Jing Nie ◽  
Tao Shen ◽  
Yingjie Xu ◽  
...  
Keyword(s):  
Circadian Rhythms ◽  
Ionizing Radiation ◽  
Mrna Expression ◽  
Sperm Motility ◽  
Clock Genes ◽  
Functional Markers ◽  
X Rays ◽  
Sperm Production ◽  
Potential Health ◽  
Daily Sperm Production

Abstract Background Exposure to the ionizing radiation (IR) encountered outside the magnetic field of the Earth poses a persistent threat to the reproductive functions of astronauts. The potential effects of space IR on the circadian rhythms of male reproductive functions have not been well characterized so far. Methods Here, we investigated the circadian effects of IR exposure (3 Gy X-rays) on reproductive functional markers in mouse testicular tissue and epididymis at regular intervals over a 24-h day. For each animal, epididymis was tested for sperm motility, and the testis tissue was used for daily sperm production (DSP), testosterone levels, and activities of testicular enzymes (glucose-6-phosphate dehydrogenase (G6PDH), sorbitol dehydrogenase (SDH), lactic dehydrogenase (LDH), and acid phosphatase (ACP)), and the clock genes mRNA expression such as Clock, Bmal1, Ror-α, Ror-β, or Ror-γ. Results Mice exposed to IR exhibited a disruption in circadian rhythms of reproductive markers, as indicated by decreased sperm motility, increased daily sperm production (DSP), and reduced activities of testis enzymes such as G6PDH, SDH, LDH, and ACP. Moreover, IR exposure also decreased mRNA expression of five clock genes (Clock, Bmal1, Ror-α, Ror-β, or Ror-γ) in testis, with alteration in the rhythm parameters. Conclusion These findings suggested potential health effects of IR exposure on reproductive functions of male astronauts, in terms of both the daily overall level as well as the circadian rhythmicity.

scholarly journals How is mRNA expression predictive for protein expression? A correlation study on human circulating monocytes

2008 ◽  
Vol 40 (5) ◽  
pp. 426-436 ◽  
Author(s):  
Yanfang Guo ◽  
Peng Xiao ◽  
Shufeng Lei ◽  
Feiyan Deng ◽  
Gary Guishan Xiao ◽  
...  
Keyword(s):  
Protein Expression ◽  
Mrna Expression ◽  
Correlation Study

Activated Prominences; Mechanisms for Activation and Eruption

1979 ◽  
Vol 44 ◽  
pp. 307-313
Author(s):  
D.S. Spicer
Keyword(s):  
Pressure Gradient ◽  
Density Gradient ◽  
Current Density ◽  
Convective Instability ◽  
Tearing Mode ◽  
Magnetic Shear ◽  
Long Wavelength ◽  
Ideal Mhd ◽  
Gradient Change ◽  
Accelerated Particles

A possible relationship between the hot prominence transition sheath, increased internal turbulent and/or helical motion prior to prominence eruption and the prominence eruption (“disparition brusque”) is discussed. The associated darkening of the filament or brightening of the prominence is interpreted as a change in the prominence’s internal pressure gradient which, if of the correct sign, can lead to short wavelength turbulent convection within the prominence. Associated with such a pressure gradient change may be the alteration of the current density gradient within the prominence. Such a change in the current density gradient may also be due to the relative motion of the neighbouring plages thereby increasing the magnetic shear within the prominence, i.e., steepening the current density gradient. Depending on the magnitude of the current density gradient, i.e., magnetic shear, disruption of the prominence can occur by either a long wavelength ideal MHD helical (“kink”) convective instability and/or a long wavelength resistive helical (“kink”) convective instability (tearing mode). The long wavelength ideal MHD helical instability will lead to helical rotation and thus unwinding due to diamagnetic effects and plasma ejections due to convection. The long wavelength resistive helical instability will lead to both unwinding and plasma ejections, but also to accelerated plasma flow, long wavelength magnetic field filamentation, accelerated particles and long wavelength heating internal to the prominence.

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