scholarly journals Glucocorticoids Reset the Nasal Circadian Clock in Mice

Endocrinology ◽  
2015 ◽  
Vol 156 (11) ◽  
pp. 4302-4311 ◽  
Author(s):  
Aya Honma ◽  
Yoshiko Yamada ◽  
Yuji Nakamaru ◽  
Satoshi Fukuda ◽  
Ken-ichi Honma ◽  
...  
Keyword(s):  
Allergic Rhinitis ◽  
Circadian Rhythm ◽  
Circadian Clock ◽  
Nasal Mucosa ◽  
Ex Vivo ◽  
Luciferase Reporter ◽  
Peripheral Tissues ◽  
Circadian Physiology ◽  
First Time

The symptoms of allergic rhinitis show marked day-night changes that are likely to be under the control of the circadian clock, but the mechanism of this control is poorly understood. Because most peripheral tissues have endogenous circadian clocks, we examined the circadian rhythm of the clock gene product PERIOD2 (PER2) in the nasal mucosa of male mice using a luciferase reporter and demonstrated for the first time the phase-dependent effects of dexamethasone (DEX) on nasal PER2 rhythm in vivo and ex vivo. The phase shifts in PER2 rhythm caused by DEX were observed around the peak phase of serum glucocorticoids, suggesting that the circadian rhythm of endogenous glucocorticoids regulates the peripheral clock of the mouse nasal mucosa. From the viewpoint of circadian physiology, the best time to administer intranasal steroid treatment for allergic rhinitis would be when no phase shift is caused by DEX: in the early evening in diurnal humans.

Abstract P466: Circadian Rhythm Disruptions in a Novel Diabetic db/db-mPer2 Luc Mouse Model

Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Tianfei Hou ◽  
Wen Su ◽  
Ming C Gong ◽  
Zhenheng Guo
Keyword(s):  
Blood Pressure ◽  
Circadian Rhythms ◽  
Real Time ◽  
Clock Gene ◽  
Ex Vivo ◽  
Phase Advance ◽  
Luciferase Reporter ◽  
High Time Resolution ◽  
Peripheral Tissues

Db/db mouse, which lacks functional leptin receptor, is an extensively used model of obesity and type 2 diabetes. We and others have demonstrated that db/db mouse has disruptions in circadian rhythms of behavior, physiology and some clock genes. However, systemic investigations of the alterations in clock gene oscillations in multiple systems with high time resolution in this model are impeded by the impractical demand for large number of animals. To overcome this limitation, we cross bred the db/db mouse with mPer2 Luc mouse in which the clock gene Period2 is fused with a luciferase reporter thus allow real-time monitoring of the clock gene Per2 oscillations. The generated db/db-mPer2 Luc mice had the typical diabetic mellitus including obesity, hyperglycemia, hyperinsulinemia, glucose intolerance and insulin resistance. In addition, the db/db-mPer2 Luc mice also exhibited disruptions in circadian rhythms in behavior (locomotor activity), physiology (blood pressure) and metabolism (respiratory exchange ratio and energy expenditure). Using the LumiCycle system, we monitored in real-time of the Per2 oscillations in both the SCN central clock and multiple peripheral tissues ex vivo . The results showed no difference in the phase of the central SCN Per2 oscillation. However, the peripheral tissues that related to metabolism, such as liver and white adipose clocks, displayed 3.28±0.86 and 4.64±1.06 hours of phase advance respectively. Aorta, mesentery artery and kidney, organs play important role in blood pressure homeostasis, showed 0.99±0.37, and 2.12±0.4, and 2.21±0.5 hours phase advance respectively. Interestingly, no difference was observed in the lung and adrenal gland. We then investigated the Per2 oscillation in vivo by using the IVIS imaging system. Consistent with the ex vivo results, the liver Per2 oscillation were phase advanced in vivo. Our findings demonstrated that clock gene Per2 oscillations were disrupted in multiple peripheral tissues but not in central SCN. Moreover, the extent of phase advance in peripheral tissue varies largely. Our results suggest dyssynchrony of the clock oscillations among various peripheral systems likely contribute to the multiple disruptions in physiology and metabolism in diabetic db/db mice.

scholarly journals Tumor Suppressive Role of miR-342-5p in Human Chondrosarcoma Cells and 3D Organoids

2021 ◽  
Vol 22 (11) ◽  
pp. 5590
Author(s):  
Clément Veys ◽  
Abderrahim Benmoussa ◽  
Romain Contentin ◽  
Amandine Duchemin ◽  
Emilie Brotin ◽  
...  
Keyword(s):  
Luciferase Reporter ◽  
Functional Screening ◽  
Western Blots ◽  
Egfr Expression ◽  
Reporter Assays ◽  
Direct Target ◽  
Induced Apoptosis ◽  
First Time

Chondrosarcomas are malignant bone tumors. Their abundant cartilage-like extracellular matrix and their hypoxic microenvironment contribute to their resistance to chemotherapy and radiotherapy, and no effective therapy is currently available. MicroRNAs (miRNAs) may be an interesting alternative in the development of therapeutic options. Here, for the first time in chondrosarcoma cells, we carried out high-throughput functional screening using impedancemetry, and identified five miRNAs with potential antiproliferative or chemosensitive effects on SW1353 chondrosarcoma cells. The cytotoxic effects of miR-342-5p and miR-491-5p were confirmed on three chondrosarcoma cell lines, using functional validation under normoxia and hypoxia. Both miRNAs induced apoptosis and miR-342-5p also induced autophagy. Western blots and luciferase reporter assays identified for the first time Bcl-2 as a direct target of miR-342-5p, and also Bcl-xL as a direct target of both miR-342-5p and miR-491-5p in chondrosarcoma cells. MiR-491-5p also inhibited EGFR expression. Finally, only miR-342-5p induced cell death on a relevant 3D chondrosarcoma organoid model under hypoxia that mimics the in vivo microenvironment. Altogether, our results revealed the tumor suppressive activity of miR-342-5p, and to a lesser extent of miR-491-5p, on chondrosarcoma lines. Through this study, we also confirmed the potential of Bcl-2 family members as therapeutic targets in chondrosarcomas.

scholarly journals Circadian Rhythm: Potential Therapeutic Target for Atherosclerosis and Thrombosis

2021 ◽  
Vol 22 (2) ◽  
pp. 676
Author(s):  
Andy W. C. Man ◽  
Huige Li ◽  
Ning Xia
Keyword(s):  
Circadian Rhythm ◽  
Cardiovascular Diseases ◽  
Circadian Rhythms ◽  
Circadian Clock ◽  
Therapeutic Target ◽  
Environmental Changes ◽  
Clock Genes ◽  
Vascular System ◽  
Peripheral Tissues ◽  
Inflammatory Processes

Every organism has an intrinsic biological rhythm that orchestrates biological processes in adjusting to daily environmental changes. Circadian rhythms are maintained by networks of molecular clocks throughout the core and peripheral tissues, including immune cells, blood vessels, and perivascular adipose tissues. Recent findings have suggested strong correlations between the circadian clock and cardiovascular diseases. Desynchronization between the circadian rhythm and body metabolism contributes to the development of cardiovascular diseases including arteriosclerosis and thrombosis. Circadian rhythms are involved in controlling inflammatory processes and metabolisms, which can influence the pathology of arteriosclerosis and thrombosis. Circadian clock genes are critical in maintaining the robust relationship between diurnal variation and the cardiovascular system. The circadian machinery in the vascular system may be a novel therapeutic target for the prevention and treatment of cardiovascular diseases. The research on circadian rhythms in cardiovascular diseases is still progressing. In this review, we briefly summarize recent studies on circadian rhythms and cardiovascular homeostasis, focusing on the circadian control of inflammatory processes and metabolisms. Based on the recent findings, we discuss the potential target molecules for future therapeutic strategies against cardiovascular diseases by targeting the circadian clock.

scholarly journals Extra-gastric expression of the proton pump H+/K+-ATPase in the gills and kidney of the teleost Oreochromis niloticus

2020 ◽  
Vol 223 (16) ◽  
pp. jeb214890
Author(s):  
Ebtesam Ali Barnawi ◽  
Justine E. Doherty ◽  
Patrícia Gomes Ferreira ◽  
Jonathan M. Wilson
Keyword(s):  
Oreochromis Niloticus ◽  
Cellular Localization ◽  
Ex Vivo ◽  
Uptake Inhibition ◽  
Custom Made ◽  
Potassium Regulation ◽  
Immunohistochemical Techniques ◽  
Collecting Tubules ◽  
First Time

ABSTRACTPotassium regulation is essential for the proper functioning of excitable tissues in vertebrates. The H+/K+-ATPase (HKA), which is composed of the HKα1 (gene: atp4a) and HKβ (gene: atp4b) subunits, has an established role in potassium and acid–base regulation in mammals and is well known for its role in gastric acidification. However, the role of HKA in extra-gastric organs such as the gill and kidney is less clear, especially in fishes. In the present study in Nile tilapia, Oreochromis niloticus, uptake of the K+ surrogate flux marker rubidium (Rb+) was demonstrated in vivo; however, this uptake was not inhibited with omeprazole, a potent inhibitor of the gastric HKA. This contrasts with gill and kidney ex vivo preparations, where tissue Rb+ uptake was significantly inhibited by omeprazole and SCH28080, another gastric HKA inhibitor. The cellular localization of this pump in both the gill and kidney was demonstrated using immunohistochemical techniques with custom-made antibodies specific for Atp4a and Atp4b. Antibodies against the two subunits showed the same apical ionocyte distribution pattern in the gill and collecting tubules/ducts in the kidney. Atp4a antibody specificity was confirmed by western blotting. RT-PCT was used to confirm the expression of both subunits in the gill and kidney. Taken together, these results indicate for the first time K+ (Rb+) uptake in O. niloticus and that HKA is implicated, as shown through the ex vivo uptake inhibition by omeprazole and SCH28080, verifying a role for HKA in K+ absorption in the gill's ionocytes and collecting tubule/duct segments of the kidney.

Abstract P283: Parkin Mediates Mitophagy in Cardioprotection

2011 ◽  
Vol 109 (suppl_1) ◽  
Author(s):  
Allen M Andres ◽  
Chengqun Huang ◽  
Eric P Ratliff ◽  
Genaro Hernandez ◽  
Pamela Lee ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Wild Type ◽  
Simulated Ischemia ◽  
Selective Targeting ◽  
Cardioprotective Effects ◽  
Mitochondrial Turnover ◽  
First Time

Autophagy-dependent mitochondrial turnover in response to cellular stress is necessary for maintaining cellular homeostasis. However, the mechanisms that govern the selective targeting of damaged mitochondria are poorly understood. Parkin, an E3 ubiquitin ligase, has been shown to be essential for the selective clearance of damaged mitochondria. Parkin is expressed in the heart, yet its function has not been investigated in the context of cardioprotection. We previously reported that autophagy is required for cardioprotection by ischemic preconditioning (IPC). In the present study, we used simulated ischemia in vitro and IPC in hearts (in vivo and ex vivo) to investigate the role of Parkin in mediating cardioprotection. In HL-1 cells, simulated ischemia induced Parkin translocation to mitochondria and mitochondrial elimination. Mitochondrial loss was blunted in Atg5-deficient cells, revealing the requirement for autophagy in mitochondrial elimination. Consistent with previous reports implicating p62/SQSTM1 in mitophagy, we found that downregulation of p62 attenuated mitophagy and exacerbated cell death in HL-1 cardiomyocytes subjected to simulated ischemia. While wild type mice showed p62 translocation to mitochondria after IPC, Parkin knockout mice exhibited attenuated translocation of p62 to mitochondria. Importantly, ablation of Parkin in mice abolished the cardioprotective effects of IPC. These results reveal for the first time the crucial role of Parkin and mitophagy in cardioprotection.

scholarly journals Maf1 regulates dendritic morphogenesis and influences learning and memory

2020 ◽  
Vol 11 (7) ◽  
Author(s):  
Kui Chen ◽  
Liang Zhu ◽  
Lin Guo ◽  
Yuan-Bo Pan ◽  
Dong-Fu Feng
Keyword(s):  
Learning And Memory ◽  
Dendritic Spines ◽  
Mtor Signaling ◽  
Pten Expression ◽  
Luciferase Reporter ◽  
Downstream Effector ◽  
Dendritic Morphogenesis ◽  
First Time

Abstract Maf1, a general transcriptional regulator and mTOR downstream effector, is highly expressed in the hippocampus and cortex, but the function of Maf1 in neurons is not well elucidated. Here, we first demonstrate that Maf1 plays a central role in the inhibition of dendritic morphogenesis and the growth of dendritic spines both in vitro and in vivo. Furthermore, Maf1 downregulation paradoxically leads to activation of AKT-mTOR signaling, which is mediated by decreased PTEN expression. Moreover, we confirmed that Maf1 could regulate the activity of PTEN promoter by luciferase reporter assay, and proved that Maf1 could bind to the promoter of PTEN by ChIP-PCR experiment. We also demonstrate that expression of Maf1 in the hippocampus affects learning and memory in mice. Taken together, we show for the first time that Maf1 inhibits dendritic morphogenesis and the growth of dendritic spines through AKT-mTOR signaling by increasing PTEN expression.

scholarly journals Candida albicans forms biofilms on the vaginal mucosa

Microbiology ◽  
2010 ◽  
Vol 156 (12) ◽  
pp. 3635-3644 ◽  
Author(s):  
M. M. Harriott ◽  
E. A. Lilly ◽  
T. E. Rodriguez ◽  
P. L. Fidel ◽  
M. C. Noverr
Keyword(s):  
Biofilm Formation ◽  
Ex Vivo ◽  
Microscopic Analysis ◽  
Vaginal Mucosa ◽  
First Time ◽  
Established Role ◽  
Type Strains

Current understanding of resistance and susceptibility to vulvovaginal candidiasis challenges existing paradigms of host defence against fungal infection. While abiotic biofilm formation has a clearly established role during systemic Candida infections, it is not known whether C. albicans forms biofilms on the vaginal mucosa and the possible role of biofilms in disease. In vivo and ex vivo murine vaginitis models were employed to examine biofilm formation by scanning electron and confocal microscopy. C. albicans strains included 3153A (lab strain), DAY185 (parental control strain), and mutants defective in morphogenesis and/or biofilm formation in vitro (efg1/efg1 and bcr1/bcr1). Both 3153A and DAY815 formed biofilms on the vaginal mucosa in vivo and ex vivo as indicated by high fungal burden and microscopic analysis demonstrating typical biofilm architecture and presence of extracellular matrix (ECM) co-localized with the presence of fungi. In contrast, efg1/efg1 and bcr1/bcr1 mutant strains exhibited weak or no biofilm formation/ECM production in both models compared to wild-type strains and complemented mutants despite comparable colonization levels. These data show for the first time that C. albicans forms biofilms in vivo on vaginal epithelium, and that in vivo biotic biofilm formation requires regulators of biofilm formation (BCR1) and morphogenesis (EFG1).

scholarly journals Single-cell analysis of circadian dynamics in tissue explants

2015 ◽  
Vol 26 (22) ◽  
pp. 3940-3945 ◽  
Author(s):  
Laura Lande-Diner ◽  
Jacob Stewart-Ornstein ◽  
Charles J. Weitz ◽  
Galit Lahav
Keyword(s):  
Circadian Clock ◽  
Single Cell ◽  
Cell Tracking ◽  
Single Cell Analysis ◽  
Single Cells ◽  
Tissue Imaging ◽  
Wide Field ◽  
Isolated Cells ◽  
Peripheral Tissues

Tracking molecular dynamics in single cells in vivo is instrumental to understanding how cells act and interact in tissues. Current tissue imaging approaches focus on short-term observation and typically nonendogenous or implanted samples. Here we develop an experimental and computational setup that allows for single-cell tracking of a transcriptional reporter over a period of >1 wk in the context of an intact tissue. We focus on the peripheral circadian clock as a model system and measure the circadian signaling of hundreds of cells from two tissues. The circadian clock is an autonomous oscillator whose behavior is well described in isolated cells, but in situ analysis of circadian signaling in single cells of peripheral tissues is as-yet uncharacterized. Our approach allowed us to investigate the oscillatory properties of individual clocks, determine how these properties are maintained among different cells, and assess how they compare to the population rhythm. These experiments, using a wide-field microscope, a previously generated reporter mouse, and custom software to track cells over days, suggest how many signaling pathways might be quantitatively characterized in explant models.

LncRNA MIAT Promotes Allergic Inflammation and Symptoms by Targeting MiR-10b-5p in Allergic Rhinitis Mice

2021 ◽  
Vol 35 (6) ◽  
pp. 781-789
Author(s):  
Zhiqi Ma ◽  
Haijuan Lian ◽  
Xiaoyan Lin ◽  
Yong Li
Keyword(s):  
Allergic Rhinitis ◽  
Nasal Mucosa ◽  
Th17 Cells ◽  
Immunoglobulin E ◽  
Allergic Inflammation ◽  
Specific Ige ◽  
Luciferase Reporter ◽  
Mice Model ◽  
Ige Response ◽  
The Relationship

Background Allergic rhinitis (AR) is one of the most common noninfectious respiratory diseases caused by immunoglobulin E (IgE) response. Objective The study sought to explore the relationship between lncRNA MIAT and miR-10b-5p and their interaction in the regulation of allergic phenotypes in allergic rhinitis (AR) mice. Methods A mice model of AR was constructed using ovalbumin (OVA) sensitization. AR mice were treated with miR-10b-5p agomiR and LNA mediated lncRNA MIAT. The targeting relationship between MIAT and miR-10b-5p was analyzed by the ENCORI website and dual-luciferase reporter assay. The numbers of rubbing and sneezing of mice were counted. Hematoxylin-eosin (HE) staining visualized the eosinophils infiltration in nasal mucosa tissues of mice. The percentage of Th17 cells was quantitated by flow cytometry analysis. ELISA was used to detect the levels of serum OVA-specific IgE, the Th12 cytokine IL-4, and inflammatory cytokines (IL-6, IL-17). Results MIAT was up-regulated in the nasal mucosa of AR mice, while miR-10b-5p was down-regulated. MIAT directly suppressed miR-10b-5p expression in AR mice. The numbers of rubbing and sneezing, the percentage of Th17 cells, and the levels of OVA-specific IgE, IL-4, IL-6, and IL-17 in AR mice were decreased by miR-10b-5p overexpression, which was reversed by MIAT overexpression. The eosinophils infiltration in AR mice was inhibited by miR-10b-5p overexpression, which was also reversed by MIAT overexpression. Conclusion The present study demonstrates that MIAT overexpression Promotes allergic inflammation and symptoms by activating Th17 immune response via miR-10b-5p inhibition.

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