Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 68
Filter
1.
World J Gastrointest Oncol ; 16(4): 1532-1546, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38660671

ABSTRACT

BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare hereditary neoplastic disorder mainly associated with serine/threonine kinase 11 (STK11/LKB1) gene mutations. Preimplantation genetic testing can protect a patient's offspring from mutated genes; however, some variations in this gene have been interpreted as variants of uncertain significance (VUS), which complicate reproductive decision-making in genetic counseling. AIM: To identify the pathogenicity of two missense variants and provide clinical guidance. METHODS: Whole exome gene sequencing and Sanger sequencing were performed on the peripheral blood of patients with PJS treated at the Reproductive and Genetic Hospital of Citic-Xiangya. Software was employed to predict the protein structure, conservation, and pathogenicity of the two missense variation sites in patients with PJS. Additionally, plasmids were constructed and transfected into HeLa cells to observe cell growth. The differences in signal pathway expression between the variant group and the wild-type group were compared using western blot and immunohistochemistry. Statistical analysis was performed using one-way analysis of variance. P < 0.05 was considered statistically significant. RESULTS: We identified two missense STK11 gene VUS [c.889A>G (p.Arg297Gly) and c.733C>T (p.Leu245Phe)] in 9 unrelated PJS families who were seeking reproductive assistance. The two missense VUS were located in the catalytic domain of serine/threonine kinase, which is a key structure of the liver kinase B1 (LKB1) protein. In vitro experiments showed that the phosphorylation levels of adenosine monophosphate-activated protein kinase (AMPK) at Thr172 and LKB1 at Ser428 were significantly higher in transfected variation-type cells than in wild-type cells. In addition, the two missense STK11 variants promoted the proliferation of HeLa cells. Subsequent immunohistochemical analysis showed that phosphorylated-AMPK (Thr172) expression was significantly lower in gastric, colonic, and uterine polyps from PJS patients with missense variations than in non-PJS patients. Our findings indicate that these two missense STK11 variants are likely pathogenic and inactivate the STK11 gene, causing it to lose its function of regulating downstream phosphorylated-AMPK (Thr172), which may lead to the development of PJS. The identification of the pathogenic mutations in these two clinically characterized PJS patients has been helpful in guiding them toward the most appropriate mode of pregnancy assistance. CONCLUSION: These two missense variants can be interpreted as likely pathogenic variants that mediated the onset of PJS in the two patients. These findings not only offer insights for clinical decision-making, but also serve as a foundation for further research and reanalysis of missense VUS in rare diseases.

2.
Article in English | MEDLINE | ID: mdl-38457239

ABSTRACT

Human neural progenitor cells (hNPCs) hold promise for treating spinal cord injury. Studies to date have focused on improving their regenerative potential and therapeutic effect. Equally important is ensuring successful delivery and engraftment of hNPCs at the injury site. Unfortunately, no current imaging solution for cell tracking is compatible with long-term monitoring in vivo. The objective of this study was to apply a novel bright-ferritin magnetic resonance imaging (MRI) mechanism to track hNPC transplants longitudinally and on demand in the rat spinal cord. We genetically modified hNPCs to stably overexpress human ferritin. Ferritin-overexpressing (FT) hNPCs labeled with 0.2 mM manganese provided significant T1-induced bright contrast on in vitro MRI, with no adverse effect on cell viability, morphology, proliferation, and differentiation. In vivo, 2 M cells were injected into the cervical spinal cord of Rowett nude rats. MRI employed T1-weighted acquisitions and T1 mapping on a 3 T scanner. Conventional short-term cell tracking was performed using exogenous Mn labeling prior to cell transplantation, which displayed transient bright contrast on MRI 1 day after cell transplantation and disappeared after 1 week. In contrast, long-term cell tracking using bright-ferritin allowed on-demand signal recall upon Mn supplementation and precise visualization of the surviving hNPC graft. In fact, this new cell tracking technology identified 7 weeks post-transplantation as the timepoint by which substantial hNPC integration occurred. Spatial distribution of hNPCs on MRI matched that on histology. In summary, bright-ferritin provides the first demonstration of long-term, on-demand, high-resolution, and specific tracking of hNPCs in the rat spinal cord.

3.
iScience ; 27(2): 109008, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38352228

ABSTRACT

Disruption of circadian rhythms during fetal development may predispose mice to developing heart disease later in life. Here, we report that male, but not female, mice that had experienced chronic circadian disturbance (CCD) in utero were more susceptible to pathological cardiac remodeling compared with mice that had developed under normal intrauterine conditions. CCD-treated males showed ventricular chamber dilatation, enhanced myocardial fibrosis, decreased contractility, higher rates of induced tachyarrhythmia, and elevated expression of biomarkers for heart failure and myocardial remodeling. In utero CCD exposure also triggered sex-dependent changes in cardiac gene expression, including upregulation of the secretoglobin gene, Scgb1a1, in males. Importantly, cardiac overexpression of Scgb1a1 was sufficient to induce myocardial hypertrophy in otherwise naive male mice. Our findings reveal that in utero CCD exposure predisposes male mice to pathological remodeling of the heart later in life, likely as a consequence of SCGB1A1 upregulation.

4.
Stem Cell Res Ther ; 14(1): 330, 2023 Nov 14.
Article in English | MEDLINE | ID: mdl-37964388

ABSTRACT

BACKGROUND: A non-invasive imaging technology that can monitor cell viability, retention, distribution, and interaction with host tissue after transplantation is needed for optimizing and translating stem cell-based therapies. Current cell imaging approaches are limited in sensitivity or specificity, or both, for in vivo cell tracking. The objective of this study was to apply a novel ferritin-based magnetic resonance imaging (MRI) platform to longitudinal tracking of human embryonic stem cells (hESCs) in vivo. METHODS: Human embryonic stem cells (hESCs) were genetically modified to stably overexpress ferritin using the CRISPR-Cas9 system. Cellular toxicity associated with ferritin overexpression and manganese (Mn) supplementation were assessed based on cell viability, proliferation, and metabolic activity. Ferritin-overexpressing hESCs were characterized based on stem cell pluripotency and cardiac-lineage differentiation capability. Cells were supplemented with Mn and imaged in vitro as cell pellets on a preclinical 3 T MR scanner. T1-weighted images and T1 relaxation times were analyzed to assess contrast. For in vivo study, three million cells were injected into the leg muscle of non-obese diabetic severe combined immunodeficiency (NOD SCID) mice. Mn was administrated subcutaneously. T1-weighted sequences and T1 mapping were used to image the animals for longitudinal in vivo cell tracking. Cell survival, proliferation, and teratoma formation were non-invasively monitored by MRI. Histological analysis was used to validate MRI results. RESULTS: Ferritin-overexpressing hESCs labeled with 0.1 mM MnCl2 provided significant T1-induced bright contrast on in vitro MRI, with no adverse effect on cell viability, proliferation, pluripotency, and differentiation into cardiomyocytes. Transplanted hESCs displayed significant bright contrast on MRI 24 h after Mn administration, with contrast persisting for 5 days. Bright contrast was recalled at 4-6 weeks with early teratoma outgrowth. CONCLUSIONS: The bright-ferritin platform provides the first demonstration of longitudinal cell tracking with signal recall, opening a window on the massive cell death that hESCs undergo in the weeks following transplantation before the surviving cell fraction proliferates to form teratomas.


Subject(s)
Human Embryonic Stem Cells , Teratoma , Mice , Animals , Humans , Human Embryonic Stem Cells/pathology , Ferritins/genetics , Mice, SCID , Magnetic Resonance Imaging/methods , Embryonic Stem Cells
5.
J Clin Invest ; 133(1)2023 01 03.
Article in English | MEDLINE | ID: mdl-36301669

ABSTRACT

Signaling circuits crucial to systemic physiology are widespread, yet uncovering their molecular underpinnings remains a barrier to understanding the etiology of many metabolic disorders. Here, we identified a copper-linked signaling circuit activated by disruption of mitochondrial function in the murine liver or heart that resulted in atrophy of the spleen and thymus and caused a peripheral white blood cell deficiency. We demonstrated that the leukopenia was caused by α-fetoprotein, which required copper and the cell surface receptor CCR5 to promote white blood cell death. We further showed that α-fetoprotein expression was upregulated in several cell types upon inhibition of oxidative phosphorylation. Collectively, our data argue that α-fetoprotein may be secreted by bioenergetically stressed tissue to suppress the immune system, an effect that may explain the recurrent or chronic infections that are observed in a subset of mitochondrial diseases or in other disorders with secondary mitochondrial dysfunction.


Subject(s)
Copper , Mitochondrial Diseases , Mice , Animals , Copper/metabolism , alpha-Fetoproteins/metabolism , Mitochondria/genetics , Mitochondria/metabolism , Mitochondrial Diseases/metabolism , Immunosuppression Therapy
6.
Int J Mol Sci ; 23(18)2022 Sep 12.
Article in English | MEDLINE | ID: mdl-36142478

ABSTRACT

Circadian clocks evolved to enable organisms to anticipate and prepare for periodic environmental changes driven by the day-night cycle. This internal timekeeping mechanism is built on autoregulatory transcription-translation feedback loops that control the rhythmic expression of core clock genes and their protein products. The levels of clock proteins rise and ebb throughout a 24-h period through their rhythmic synthesis and destruction. In the ubiquitin-proteasome system, the process of polyubiquitination, or the covalent attachment of a ubiquitin chain, marks a protein for degradation by the 26S proteasome. The process is regulated by E3 ubiquitin ligases, which recognize specific substrates for ubiquitination. In this review, we summarize the roles that known E3 ubiquitin ligases play in the circadian clocks of two popular model organisms: mice and fruit flies. We also discuss emerging evidence that implicates the N-degron pathway, an alternative proteolytic system, in the regulation of circadian rhythms. We conclude the review with our perspectives on the potential for the proteolytic and non-proteolytic functions of E3 ubiquitin ligases within the circadian clock system.


Subject(s)
Circadian Clocks , Circadian Rhythm , Animals , CLOCK Proteins , Circadian Clocks/genetics , Circadian Rhythm/genetics , Drosophila/metabolism , Proteasome Endopeptidase Complex/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitins
7.
PLoS One ; 17(9): e0273098, 2022.
Article in English | MEDLINE | ID: mdl-36107951

ABSTRACT

Naked mole-rats are a long-lived rodent species (current lifespan >37 years) and an increasingly popular biomedical model. Naked mole-rats exhibit neuroplasticity across their long lifespan. Previous studies have begun to investigate their neurogenic patterns. Here, we test the hypothesis that neuronal maturation is extended in this long-lived rodent. We characterize cell proliferation and neuronal maturation in established rodent neurogenic regions over 12 months following seven days of consecutive BrdU injection. Given that naked mole-rats are eusocial (high reproductive skew where only a few socially-dominant individuals reproduce), we also looked at proliferation in brain regions relevant to the social-decision making network. Finally, we measured co-expression of EdU (newly-born cells), DCX (immature neuron marker), and NeuN (mature neuron marker) to assess the timeline of neuronal maturation in adult naked mole-rats. This work reaffirms the subventricular zone as the main source of adult cell proliferation and suggests conservation of the rostral migratory stream in this species. Our profiling of socially-relevant brain regions suggests that future work which manipulates environmental context can unveil how newly-born cells integrate into circuitry and facilitate adult neuroplasticity. We also find naked mole-rat neuronal maturation sits at the intersection of rodents and long-lived, non-rodent species: while neurons can mature by 3 weeks (rodent-like), most neurons mature at 5 months and hippocampal neurogenic levels are low (like long-lived species). These data establish a timeline for future investigations of longevity- and socially-related manipulations of naked mole-rat adult neurogenesis.


Subject(s)
Mole Rats , Neurogenesis , Animals , Bromodeoxyuridine , Longevity/physiology , Mole Rats/physiology , Neurons/physiology
8.
Ecotoxicol Environ Saf ; 241: 113723, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35679725

ABSTRACT

Constitutional delay of growth and puberty (CDGP) refers to the late onset of puberty. CDGP is associated with poor psychosocial outcomes and elevated risk of cardiovascular and osteoporotic diseases, especially in women. The environmental factors that contribute to CDGP are poorly understood. Here, we investigated the effects of chronic circadian disturbance (CCD) during the fetal stage on the pubertal development of female mice. Compared to non-stressed female (NS-F) mice that were not exposed to CCD in utero, adolescent CCD female (CCD-F) mice exhibited phenotypes that were consistent with CDGP, including lower body weight, reduced levels of circulating gonadal hormones, decreased expression of gonadal hormones and steroid synthesis-related enzymes in the ovary and hypothalamus, irregular estrus cycles, and tardive vaginal introitus initial opening (VO) days (equivalent to the menarche). Phenotypic differences in the above-noted parameters were not observed in CCD-F mice once they had reached adulthood. The expression of genes involved in fatty acid metabolism was perturbed in the ovary and hypothalamus of CCD-F mice. In addition, the ovaries of these animals exhibited altered diurnal expression profiles of circadian clock genes. Together, our findings not only suggest that CCD during fetal development may result in delayed puberty in female mice, they also offer insights on potential mechanisms that underlie CDGP.


Subject(s)
Puberty, Delayed , Animals , Circadian Rhythm , Female , Humans , Mice , Puberty
9.
Nat Commun ; 13(1): 1594, 2022 03 24.
Article in English | MEDLINE | ID: mdl-35332162

ABSTRACT

Ubiquitin ligases control the degradation of core clock proteins to govern the speed and resetting properties of the circadian pacemaker. However, few studies have addressed their potential to regulate other cellular events within clock neurons beyond clock protein turnover. Here, we report that the ubiquitin ligase, UBR4/POE, strengthens the central pacemaker by facilitating neuropeptide trafficking in clock neurons and promoting network synchrony. Ubr4-deficient mice are resistant to jetlag, whereas poe knockdown flies are prone to arrhythmicity, behaviors reflective of the reduced axonal trafficking of circadian neuropeptides. At the cellular level, Ubr4 ablation impairs the export of secreted proteins from the Golgi apparatus by reducing the expression of Coronin 7, which is required for budding of Golgi-derived transport vesicles. In summary, UBR4/POE fulfills a conserved and unexpected role in the vesicular trafficking of neuropeptides, a function that has important implications for circadian clock synchrony and circuit-level signal processing.


Subject(s)
Circadian Clocks , Drosophila Proteins , Neuropeptides , Animals , CLOCK Proteins/metabolism , Calmodulin-Binding Proteins/metabolism , Circadian Clocks/genetics , Circadian Rhythm , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Mice , Neuropeptides/genetics , Neuropeptides/metabolism , Ubiquitin/metabolism , Ubiquitin-Protein Ligases/metabolism
10.
Neurol Int ; 13(4): 541-554, 2021 Oct 26.
Article in English | MEDLINE | ID: mdl-34842772

ABSTRACT

Mood disorders negatively impact the lives of hundreds of millions of individuals worldwide every year, yet the precise molecular mechanisms by which they manifest remain elusive. Circadian dysregulation is one avenue by which mood disorders are thought to arise. SOX2 is a transcription factor that is highly expressed in the murine suprachiasmatic nucleus (SCN), the circadian master clock, and has been recently found to be an important regulator of Per2, a core component of the molecular clock. Genetic ablation of the Sox2 gene in GABAergic neurons selectively impacts SCN neurons, as they are one of very few, if not the only, GABAergic populations that express Sox2. Here, we show that GABAergic-restricted ablation of Sox2 results in anxio-depressive-like phenotypes in mice as observed in the elevated plus maze, forced swim test, tail suspension test, and sucrose preference test. We further observe a reduction in basal and/or forced swim-induced c-Fos expression, a marker of neuronal activation, in the nucleus incertus, arcuate nucleus, and dentate gyrus of Sox2 conditional knockout (cKO) mice. Given the restricted disruption of SOX2 expression in the SCN of Sox2 cKO mice, we propose that their mood-associated phenotypes are the consequence of a dysregulated central clock that is unable to communicate appropriately timed signals to other brain nuclei that regulate affective behaviors.

11.
Cell Rep ; 36(11): 109704, 2021 09 14.
Article in English | MEDLINE | ID: mdl-34525369

ABSTRACT

Histone variants are crucial regulators of chromatin structure and gene transcription, yet their functions within the brain remain largely unexplored. Here, we show that the H2A histone variant H2A.Z is essential for neuronal survival. Mice lacking H2A.Z in GABAergic neurons or Purkinje cells (PCs) present with a progressive cerebellar ataxia accompanied by widespread degeneration of PCs. Ablation of H2A.Z in other neuronal subtypes also triggers cell death. H2A.Z binds to the promoters of key nuclear-encoded mitochondrial genes to regulate their expression and promote organelle function. Bolstering mitochondrial activity genetically or by organelle transplant enhances the survival of H2A.Z-ablated neurons. Changes in bioenergetic status alter H2A.Z occupancy at the promoters of nuclear-encoded mitochondrial genes, an adaptive response essential for cell survival. Our results highlight that H2A.Z fulfills a key, conserved role in neuronal survival by acting as a transcriptional rheostat to regulate the expression of genes critical to mitochondrial function.


Subject(s)
Cell Nucleus/metabolism , Histones/genetics , Mitochondria/metabolism , Transcriptome , Animals , Cell Survival/drug effects , Cells, Cultured , Down-Regulation , Fibroblasts/cytology , Fibroblasts/metabolism , GABAergic Neurons/cytology , GABAergic Neurons/metabolism , Histones/deficiency , Histones/metabolism , Metformin/pharmacology , Mice , Mice, Inbred C57BL , Mice, Knockout , Mitochondria/genetics , Mitochondrial Proteins/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Oxidative Phosphorylation , Purkinje Cells/cytology , Purkinje Cells/metabolism , Transcriptome/drug effects , Up-Regulation
12.
Front Neurosci ; 15: 659974, 2021.
Article in English | MEDLINE | ID: mdl-33833665

ABSTRACT

The suprachiasmatic nucleus (SCN) of the hypothalamus is the central circadian clock of mammals. It is responsible for communicating temporal information to peripheral oscillators via humoral and endocrine signaling, ultimately controlling overt rhythms such as sleep-wake cycles, body temperature, and locomotor activity. Given the heterogeneity and complexity of the SCN, its genesis is tightly regulated by countless intrinsic and extrinsic factors. Here, we provide a brief overview of the development of the SCN, with special emphasis on the murine system.

13.
Int J Mol Sci ; 23(1)2021 Dec 26.
Article in English | MEDLINE | ID: mdl-35008655

ABSTRACT

In mammals, the hypothalamic suprachiasmatic nucleus (SCN) functions as the central circadian pacemaker, orchestrating behavioral and physiological rhythms in alignment to the environmental light/dark cycle. The neurons that comprise the SCN are anatomically and functionally heterogeneous, but despite their physiological importance, little is known about the pathways that guide their specification and differentiation. Here, we report that the stem/progenitor cell transcription factor, Sex determining region Y-box 2 (Sox2), is required in the embryonic SCN to control the expression of SCN-enriched neuropeptides and transcription factors. Ablation of Sox2 in the developing SCN leads to downregulation of circadian neuropeptides as early as embryonic day (E) 15.5, followed by a decrease in the expression of two transcription factors involved in SCN development, Lhx1 and Six6, in neonates. Thymidine analog-retention assays revealed that Sox2 deficiency contributed to reduced survival of SCN neurons during the postnatal period of cell clearance, but did not affect progenitor cell proliferation or SCN specification. Our results identify SOX2 as an essential transcription factor for the proper differentiation and survival of neurons within the developing SCN.


Subject(s)
Cell Differentiation , Embryonic Development , Neurons/metabolism , SOXB1 Transcription Factors/metabolism , Suprachiasmatic Nucleus/metabolism , Animals , Circadian Rhythm , Mice , Neurons/physiology , SOXB1 Transcription Factors/physiology , Suprachiasmatic Nucleus/growth & development , Suprachiasmatic Nucleus/physiology
14.
iScience ; 23(8): 101350, 2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32707432

ABSTRACT

A major unresolved challenge in cell-based regenerative medicine is the absence of non-invasive technologies for tracking cell fate in deep tissue and with high spatial resolution over an extended interval. MRI is highly suited for this task, but current methods fail to provide longitudinal monitoring or high sensitivity, or both. In this study, we fill this technological gap with the first discovery and demonstration of in vivo cellular production of endogenous bright contrast via an MRI genetic reporter system that forms manganese-ferritin nanoparticles. We demonstrate this technology in human embryonic kidney cells genetically modified to stably overexpress ferritin and show that, in the presence of manganese, these cells produce far greater contrast than conventional ferritin overexpression with iron or manganese-permeable cells. In living mice, diffusely implanted bright-ferritin cells produce the highest and most sustained contrast in skeletal muscle. The bright-ferritin platform has potential for on-demand, longitudinal, and sensitive cell tracking in vivo.

15.
Genome Biol Evol ; 12(8): 1217-1239, 2020 08 01.
Article in English | MEDLINE | ID: mdl-32413100

ABSTRACT

The precise localization of CaV2 voltage-gated calcium channels at the synapse active zone requires various interacting proteins, of which, Rab3-interacting molecule or RIM is considered particularly important. In vertebrates, RIM interacts with CaV2 channels in vitro via a PDZ domain that binds to the extreme C-termini of the channels at acidic ligand motifs of D/E-D/E/H-WC-COOH, and knockout of RIM in vertebrates and invertebrates disrupts CaV2 channel synaptic localization and synapse function. Here, we describe a previously uncharacterized clade of RIM proteins bearing domain architectures homologous to those of known RIM homologs, but with some notable differences including key amino acids associated with PDZ domain ligand specificity. This novel RIM emerged near the stem lineage of metazoans and underwent extensive losses, but is retained in select animals including the early-diverging placozoan Trichoplax adhaerens, and molluscs. RNA expression and localization studies in Trichoplax and the mollusc snail Lymnaea stagnalis indicate differential regional/tissue type expression, but overlapping expression in single isolated neurons from Lymnaea. Ctenophores, the most early-diverging animals with synapses, are unique among animals with nervous systems in that they lack the canonical RIM, bearing only the newly identified homolog. Through phylogenetic analysis, we find that CaV2 channel D/E-D/E/H-WC-COOH like PDZ ligand motifs were present in the common ancestor of cnidarians and bilaterians, and delineate some deeply conserved C-terminal structures that distinguish CaV1 from CaV2 channels, and CaV1/CaV2 from CaV3 channels.


Subject(s)
Calcium Channels/genetics , Evolution, Molecular , Phylogeny , Placozoa/genetics , rab GTP-Binding Proteins/genetics , Amino Acid Sequence , Animals , Calcium Channels/metabolism , Lymnaea/genetics , Placozoa/chemistry , Placozoa/metabolism , rab GTP-Binding Proteins/chemistry , rab GTP-Binding Proteins/metabolism
16.
FASEB J ; 33(11): 12240-12252, 2019 11.
Article in English | MEDLINE | ID: mdl-31431066

ABSTRACT

It is recognized that stress can induce cardiac dysfunction, but the underlying mechanisms are not well understood. The present study aimed to test the hypothesis that chronic negative stress leads to alterations in DNA methylation of certain cardiac genes, which in turn contribute to pathologic remodeling of the heart. We found that mice that were exposed to chronic restraint stress (CRS) for 4 wk exhibited cardiac remodeling toward heart failure, as characterized by ventricular chamber dilatation, wall thinning, and decreased contractility. CRS also induced cardiac arrhythmias, including intermittent sinus tachycardia and bradycardia, frequent premature ventricular contraction, and sporadic atrioventricular conduction block. Circulating levels of stress hormones were elevated, and the cardiac expression of tyrosine hydroxylase, a marker of sympathetic innervation, was increased in CRS mice. Using reduced representation bisulfite sequencing, we found that although CRS did not lead to global changes in DNA methylation in the murine heart, it nevertheless altered methylation at specific genes that are associated with the dilated cardiomyopathy (DCM) (e.g., desmin) and adrenergic signaling of cardiomyocytes (ASPC) (e.g., adrenergic receptor-α1) pathways. We conclude that CRS induces cardiac remodeling and arrhythmias, potentially through altered methylation of myocardial genes associated with the DCM and ASPC pathways.-Zhang, P., Li, T., Liu, Y.-Q., Zhang, H., Xue, S.-M., Li, G., Cheng, H.-Y.M., Cao, J.-M. Contribution of DNA methylation in chronic stress-induced cardiac remodeling and arrhythmias in mice.


Subject(s)
Arrhythmias, Cardiac/etiology , DNA Methylation , Stress, Psychological/complications , Ventricular Remodeling/physiology , Animals , Chronic Disease , Heart/innervation , Heart Failure/pathology , Male , Mice , Mice, Inbred C57BL , Receptors, Adrenergic, alpha-1/physiology
17.
J Biol Rhythms ; 34(6): 634-644, 2019 12.
Article in English | MEDLINE | ID: mdl-31452438

ABSTRACT

The principal circadian pacemaker in mammals, the suprachiasmatic nucleus (SCN), expresses a number of neuropeptides that facilitate intercellular synchrony, helping to generate coherent outputs to peripheral clocks throughout the body. In particular, arginine vasopressin (AVP)- and vasoactive intestinal peptide (VIP)-expressing neurons have been recognized as crucial subpopulations within the SCN and have thus been the focus of many chronobiological studies. Here, we analyze the neuropeptide expression of 2 popular transgenic mouse strains commonly used to direct or restrict Cre-mediated recombination to AVP- and VIP-ergic neurons. The Avp-IRES2-Cre (JAX #023530) and Vip-IRES-Cre (JAX #010908) "driver" mouse strains express the Cre recombinase under the control of the endogenous Avp or Vip gene, respectively, allowing scientists either to ablate their gene of interest or to overexpress a transgene in a cell type-specific manner. Although these are potentially very powerful tools for chronobiologists and other scientists studying AVP- and VIP-ergic neurons, we found that neuropeptide expression in these mice is significantly decreased when an IRES(2)-Cre cassette is inserted downstream of the neuropeptide-encoding gene locus. The impact of IRES(2)-Cre cassette insertion on neuropeptide expression may be a confounding factor in many experimental designs. Our findings suggest that extreme caution must be exercised when using these mouse models to avoid misinterpretation of empirical results.


Subject(s)
Arginine Vasopressin/genetics , Circadian Clocks , Gene Expression , Mice, Transgenic , Vasoactive Intestinal Peptide/genetics , Animals , Chronobiology Phenomena , Circadian Rhythm , Female , Integrases/genetics , Male , Mice , Neurons/physiology , Suprachiasmatic Nucleus/cytology , Suprachiasmatic Nucleus/physiology
18.
Int J Mol Sci ; 20(9)2019 May 13.
Article in English | MEDLINE | ID: mdl-31086044

ABSTRACT

The central pacemakers of circadian timekeeping systems are highly robust yet adaptable, providing the temporal coordination of rhythms in behavior and physiological processes in accordance with the demands imposed by environmental cycles. These features of the central pacemaker are achieved by a multi-oscillator network in which individual cellular oscillators are tightly coupled to the environmental day-night cycle, and to one another via intercellular coupling. In this review, we will summarize the roles of various neurotransmitters and neuropeptides in the regulation of circadian entrainment and synchrony within the mammalian and Drosophila central pacemakers. We will also describe the diverse functions of protein kinases in the relay of input signals to the core oscillator or the direct regulation of the molecular clock machinery.


Subject(s)
Circadian Rhythm/physiology , Neuropeptides/metabolism , Signal Transduction/physiology , Animals , Drosophila , Humans , Mice , Suprachiasmatic Nucleus/metabolism
19.
Medicine (Baltimore) ; 98(18): e15374, 2019 May.
Article in English | MEDLINE | ID: mdl-31045783

ABSTRACT

There is scarce evidence regarding the association between the consumption of vegetables and fruits and depressive symptoms in Chinese population. The purpose of this study was to ascertain the influence of vegetables and fruits consumption on depressive symptoms in a middle-aged Chinese population. This study comprised 1676 Chinese adults aged between 45 and 59 years, who participated in a Health Survey at the time of periodic checkup in the city of Linyi, Shandong Province, China. Dietary intake was assessed using a semi-quantitative food frequency questionnaire (FFQ). Depressive symptoms were assessed using the Center for Epidemiological Studies Depression (CES-D) scale. Log-binomial regression analysis was used to evaluate the association between the consumption of vegetables and fruits and depressive symptoms. A total of 53 participants (3.2%) were classified as having depressive symptoms. After adjustment for confounding variables, participants in the highest quartile of the fruits consumption and vegetables consumption had lower prevalence ratio (PR) for depressive symptoms (PR = 0.76; 95% confidence interval [CI]: 0.603-0.974, P = .042; PR = 0.77; 95% CI: 0.612-0.977, P = .045) than those in the lowest quartile. Moreover, those in the highest quartile of total vegetables and fruits consumption had also a lower PR of depressive symptoms (PR = 0.67; 95% CI: 0.503-0.806, P = .037) than did those in the lowest quartile.Our findings indicate that higher consumption of vegetables and fruits is significantly associated with a lower risk of depressive symptoms. Further prospective studies are needed to confirm these findings.


Subject(s)
Depression/epidemiology , Fruit , Vegetables , China/epidemiology , Cross-Sectional Studies , Diet , Female , Health Surveys , Humans , Male , Middle Aged , Prevalence , Prospective Studies
20.
Data Brief ; 24: 103909, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31061857

ABSTRACT

SOX2 is a stem cell-associated pluripotency transcription factor whose role in neuronal populations is undefined. Here we present the RNA-sequencing based transcriptome profiles of control (Sox2 fl/fl ) and SOX2 conditional knock-out (Vgat-cre;Sox2 fl/fl ) mice at four time points in one 24-h circadian cycle. The raw sequencing data were deposited to ArrayExpress database at EMBL-EBI (https://www.ebi.ac.uk/arrayexpress) under the accession number E-MTAB-7496. Results of rhythmicity analysis, differential expression analysis, network prediction, and potential target identification stemming from the RNA-sequencing dataset are also given in this article. The interpretation and discussion of these data can be found in the related research article entitled "SOX2-dependent transcription in clock neurons promotes the robustness of the central circadian pacemaker." Cheng et al. 2019.

SELECTION OF CITATIONS
SEARCH DETAIL
...