Abstract 1414: Pim-1 Stimulates Cardiac Progenitor Cell Proliferation And Asymmetric Division

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Christopher T Cottage ◽  
Savilla Tuck ◽  
Kimberlee Fischer ◽  
Natalie Gude ◽  
John Muraski ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Cell Fate ◽  
Cellular Proliferation ◽  
Gene Promoter ◽  
Asymmetric Division ◽  
Postnatal Growth ◽  
Chain Gene ◽  
Ki 67 ◽  
Population Number ◽  
Mechanistic Basis

Cardiac progenitor cells (CPCs) blunt cardiomyopathic damage and increase survival following adoptive transfer into hearts subjected to myocardial infarction (MI), but the initial survival, persistence, and long term engraftment of the donated cell population remains problematic. Previous studies from our group have demonstrated that transgenes driven by the α -myosin heavy chain gene promoter are expressed in the CPC population allowing for enhanced proliferation and survival. This study details a genetic engineering strategy to augment the salutary effects of CPCs through the use of a serine/threonine kinase named Pim-1 that promotes cellular proliferation and survival. Transgenic mice created with cardiac-specific Pim-1 overexpression (Pim-wt) exhibit enhanced Pim-1 activity in both cardiomyocytes and CPCs, both of which show increased proliferative activity assessed using BrdU or Ki-67 markers relative to non-transgenic (NTG) controls. However, CPC population number was not increased in the Pim-wt hearts during normal postnatal growth or after infarction challenge, suggesting that Pim-1 expression promotes asymmetric division resulting in maintenance of the CPC pool as well as expansion of the cardiomyocyte population. Localization and quantitation of cell fate determinants Numb and α -adaptin by confocal microscopy were employed to assess levels of asymmetric division in the CPC population. Polarization of Numb in mitotic phospho-histone positive cells demonstrates asymmetric division in 65% of the CPC population in hearts of Pim-wt mice versus 26% in NTG hearts after infarction challenge. Similarly, Pim-wt hearts had fewer cells with uniform α -adaptin staining indicative of symmetrically dividing CPCs, with in 36% of the CPCs versus vs. 73% in NTG sections. These findings define a mechanistic basis for enhanced myocardial regeneration in transgenic mice overexpressing Pim-1 kinase in the myocardial lineage cells.

scholarly journals Tissue-specific regulation of the alpha-myosin heavy chain gene promoter in transgenic mice.

1991 ◽  
Vol 266 (36) ◽  
pp. 24613-24620
Author(s):  
A. Subramaniam ◽  
W.K. Jones ◽  
J. Gulick ◽  
S. Wert ◽  
J. Neumann ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Gene Promoter ◽  
Chain Gene ◽  
Heavy Chain Gene ◽  
Myosin Heavy Chain Gene ◽  
Tissue Specific ◽  
Specific Regulation

Annexin VI overexpression targeted to heart alters cardiomyocyte function in transgenic mice

1996 ◽  
Vol 270 (3) ◽  
pp. H1091-H1100 ◽  
Author(s):  
A. M. Gunteski-Hamblin ◽  
G. Song ◽  
R. A. Walsh ◽  
M. Frenzke ◽  
G. P. Boivin ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Pulmonary Veins ◽  
Gene Promoter ◽  
Transgenic Animals ◽  
Lymphocytic Infiltration ◽  
Chain Gene ◽  
Release Channel ◽  
Annexin Vi ◽  
Pathological Evaluation ◽  
Transgenic Lines

Annexin VI is a member of a family of Ca(2+)-dependent phospholipid-binding proteins that is expressed in many tissues, including the heart. It is a regulator of membrane-associated events, including the skeletal muscle ryanodine-sensitive Ca2+ release channel and the cardiac Na+/Ca2+ exchanger. The potential roles of annexin VI in Ca2+ signaling in cardiac myocytes were evaluated by targeting its overexpression to the hearts of transgenic mice. Expression of full-length human annexin VI cDNA was targeted to the heart using the alpha-myosin heavy chain gene promoter (Subramaniam, A., W. K. Jones, J. Gulick, S. Wert, J. Neumann, and J. Robbins. J. Biol. Chem. 266: 24613-24620, 1991). Five transgenic lines exhibited at least 10-fold overexpression of annexin VI protein in both atria and ventricles. Pathological evaluation indicated mice overexpressing annexin VI had enlarged dilated hearts, acute diffuse myocarditis, lymphocytic infiltration, moderate to severe fibrosis throughout the heart, and mild fibrosis around the pulmonary veins of the lungs. Contractile mechanics of cardiomyocytes isolated from hearts of transgenic animals showed frequency-dependent reduced percent shortening and decreased rates of contraction and relaxation compared with control animals. Cardiomyocytes isolated from transgenic animals had lower basal levels of intracellular free Ca2+ and a reduced rise in free Ca2+ following depolarization. After stimulation, intracellular free Ca2+ returned to basal levels faster in transgenic cells than in cells from control animals. These data demonstrate that the overexpression of annexin VI in the heart disrupts normal Ca2+ homeostasis and suggests that this dysfunction may be due to annexin VI regulation of pumps and/or exchangers in the membranes of cardiomyocytes.

scholarly journals SARS-CoV-2 infection in the lungs of human ACE2 transgenic mice causes severe inflammation, immune cell infiltration, and compromised respiratory function

2020 ◽  
Author(s):  
Emma S. Winkler ◽  
Adam L. Bailey ◽  
Natasha M. Kafai ◽  
Sharmila Nair ◽  
Broc T. McCune ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Lung Disease ◽  
Immune Cell ◽  
Gene Promoter ◽  
Type I ◽  
Sequencing Analysis ◽  
Interferon Signaling ◽  
Activated T Cells ◽  
Mechanistic Basis ◽  
Activation Pathways

ABSTRACTSevere Acute Respiratory Syndrome Coronavirus -2 (SARS-CoV-2) emerged in late 2019 and has spread worldwide resulting in the Coronavirus Disease 2019 (COVID-19) pandemic. Although animal models have been evaluated for SARS-CoV-2 infection, none have recapitulated the severe lung disease phenotypes seen in hospitalized human cases. Here, we evaluate heterozygous transgenic mice expressing the human ACE2 receptor driven by the epithelial cell cytokeratin-18 gene promoter (K18-hACE2) as a model of SARS-CoV-2 infection. Intranasal inoculation of SARS-CoV-2 in K18-hACE2 mice results in high levels of viral infection in lung tissues with additional spread to other organs. Remarkably, a decline in pulmonary function, as measured by static and dynamic tests of respiratory capacity, occurs 4 days after peak viral titer and correlates with an inflammatory response marked by infiltration into the lung of monocytes, neutrophils, and activated T cells resulting in pneumonia. Cytokine profiling and RNA sequencing analysis of SARS-CoV-2-infected lung tissues show a massively upregulated innate immune response with prominent signatures of NF-kB-dependent, type I and II interferon signaling, and leukocyte activation pathways. Thus, the K18-hACE2 model of SARS-CoV-2 infection recapitulates many features of severe COVID-19 infection in humans and can be used to define the mechanistic basis of lung disease and test immune and antiviral-based countermeasures.

scholarly journals Characterization of Cytokines and Proliferation Marker Ki67 in Chronic Rhinosinusitis with Nasal Polyps: A Pilot Study

Medicina ◽  
2021 ◽  
Vol 57 (6) ◽  
pp. 607
Author(s):  
Rudolfs Janis Viksne ◽  
Gunta Sumeraga ◽  
Mara Pilmane
Keyword(s):  
Connective Tissue ◽  
Chronic Rhinosinusitis ◽  
Nasal Polyps ◽  
Cellular Proliferation ◽  
Rank Correlation ◽  
Control Group ◽  
Relative Distribution ◽  
Proliferation Marker ◽  
Ki 67 ◽  
Stimulation Of

Background and Objectives: Chronic rhinosinusitis (CRS) is a condition that affects as much as 10.9% of the population and, along with presence of nasal polyps, is associated with significant morbidity and decreased quality of life. Studies on molecular pathways that have been activated in nasal polyp tissue are mainly based on cytokine concentration detection. Therefore, our aim is to investigate the complex appearance, relative distribution and interlinks of IL-1, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 and Ki 67 in chronic rhinosinusitis with nasal polyps (CRSwNP) affected human nasal mucosa. Materials and Methods: Samples of nasal polyps were obtained from 12 patients with previously diagnosed CRSwNP and no prior surgery. Control group consisted of samples from 17 otherwise healthy individuals with isolated nasal septum deviation. Tissues were stained for IL-1, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 and Ki67 immunohistochemically. Non-parametric statistic, Mann–Whitney U test and Spearman’s rank correlation coefficient were used. Results: All factors, except connective tissue cytokine IL-10 and proliferation marker Ki-67, had increased presence in connective tissue and decreased presence in epithelium of nasal polyps when compared to controls. Very strong and strong positive correlations between factors were observed. Conclusions: Decreased appearance of IL-1α, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 positive structures in the nasal epithelium with selective increase of IL-1α and IL-12 in nasal subepithelial connective tissue characterize the cytokine endotype with dysfunctional epithelial barrier and local stimulation of immune response in the connective tissue in case of chronic rhinosinusitis with polyps. Decrease of IL-6 in both—epithelium and connective tissue with strong correlation between it and IL-7 and IL-10 in connective tissue suggests significant stimulation of this regulatory cytokine and, possibly, the important role in pathogenesis of the development in nasal polyps. Correlations between Ki67 and cytokines indicate possible involvement of IL-4, IL-7 and IL-12 in regulation of cellular proliferation.

scholarly journals Mice lacking β-carotene-15,15’-dioxygenase exhibit reduced serum testosterone, prostatic androgen receptor signaling, and prostatic cellular proliferation

2016 ◽  
Vol 311 (6) ◽  
pp. R1135-R1148 ◽  
Author(s):  
Joshua W. Smith ◽  
Nikki A. Ford ◽  
Jennifer M. Thomas-Ahner ◽  
Nancy E. Moran ◽  
Eric C. Bolton ◽  
...  
Keyword(s):  
Androgen Receptor ◽  
Cellular Proliferation ◽  
Serum Testosterone ◽  
Cell Number ◽  
Immunofluorescent Staining ◽  
Receptor Signaling ◽  
Ki 67 ◽  
Androgen Receptor Signaling ◽  
Testosterone Levels ◽  
Β Carotene

β-Carotene-15,15’-dioxygenase (BCO1) cleaves dietary carotenoids at the central 15,15’ double bond, most notably acting on β-carotene to yield retinal. However, Bco1 disruption also impacts diverse physiological end points independent of dietary carotenoid feeding, including expression of genes controlling androgen metabolism. Using the Bco1−/− mouse model, we sought to probe the effects of Bco1 disruption on testicular steroidogenesis, prostatic androgen signaling, and prostatic proliferation. Male wild-type (WT) and Bco1−/− mice were raised on carotenoid-free AIN-93G diets before euthanasia between 10 and 14 wk of age. Weights of the prostate and seminal vesicles were significantly lower in Bco1−/− than in WT mice (−18% and −29%, respectively). Serum testosterone levels in Bco1−/− mice were significantly reduced by 73%. Bco1 disruption significantly reduced Leydig cell number and decreased testicular mRNA expression of Hsd17b3, suggesting inhibition of testicular testosterone synthesis. Immunofluorescent staining of the androgen receptor (AR) in the dorsolateral prostate lobes of Bco1−/− mice revealed a decrease in AR nuclear localization. Analysis of prostatic morphology suggested decreases in gland size and secretion. These findings were supported by reduced expression of the proliferation marker Ki-67 in Bco1−/− prostates. Expression analysis of 200 prostate cancer- and androgen-related genes suggested that Bco1 loss significantly disrupted prostatic androgen receptor signaling, cell cycle progression, and proliferation. This is the first demonstration that Bco1 disruption lowers murine circulating testosterone levels and thereby reduces prostatic androgen receptor signaling and prostatic cellular proliferation, further supporting the role of this protein in processes more diverse than carotenoid cleavage.

scholarly journals The c-myc proto-oncogene regulates cardiac development in transgenic mice.

1990 ◽  
Vol 10 (7) ◽  
pp. 3709-3716 ◽  
Author(s):  
T Jackson ◽  
M F Allard ◽  
C M Sreenan ◽  
L K Doss ◽  
S P Bishop ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Mrna Expression ◽  
Cardiac Myocyte ◽  
Cellular Proliferation ◽  
Cardiac Development ◽  
Constitutive Expression ◽  
Transgenic Animals ◽  
Hypertrophic Growth ◽  
Myocyte Proliferation

During the maturation of the cardiac myocyte, a transition occurs from hyperplastic to hypertrophic growth. The factors that control this transition in the developing heart are unknown. Proto-oncogenes such as c-myc have been implicated in the regulation of cellular proliferation and differentiation, and in the heart the switch from myocyte proliferation to terminal differentiation is synchronous with a decrease in c-myc mRNA abundance. To determine whether c-myc can influence myocyte proliferation or differentiation, we examined the in vivo effect of increasing c-myc expression during embryogenesis and of preventing the decrease in c-myc mRNA expression that normally occurs during cardiac development. The model system used was a strain of transgenic mice exhibiting constitutive expression of c-myc mRNA in cardiac myocytes throughout development. In these transgenic mice, increased c-myc mRNA expression was found to be associated with both atrial and ventricular enlargement. This increase in cardiac mass was secondary to myocyte hyperplasia, with the transgenic hearts containing more than twice as many myocytes as did nontransgenic hearts. The results suggest that in the transgenic animals there is additional hyperplastic growth during fetal development. However, this additional proliferative growth is not reflected in abnormal myocyte maturation, as assessed by the expression of the cardiac and skeletal isoforms of alpha-actin. The results of this study indicate that constitutive expression of c-myc mRNA in the heart during development results in enhanced hyperplastic growth and suggest a regulatory role for this proto-oncogene in cardiac myogenesis.

Analysis of lens cell fate and eye morphogenesis in transgenic mice ablated for cells of the lens lineage

Development ◽  
1989 ◽  
Vol 106 (3) ◽  
pp. 457-463 ◽  
Author(s):  
M.L. Breitman ◽  
D.M. Bryce ◽  
E. Giddens ◽  
S. Clapoff ◽  
D. Goring ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Cell Fate ◽  
Vitreous Body ◽  
Cell Types ◽  
Ciliary Epithelium ◽  
Specific Cell ◽  
Promoter Sequences ◽  
Fiber Cells ◽  
Lens Cell ◽  
Diphtheria Toxin A

Transgenic mice carrying the diphtheria toxin A gene driven by mouse gamma 2-crystallin promoter sequences manifest microphthalmia due to ablation of fiber cells in the ocular lens. Here we map ablation events in the lens by crossing animals hemizygous for the ablation construct with transgenic mice homozygous for the in situ lacZ reporter gene driven by identical gamma 2-crystallin promoter sequences. By comparing the spatial distribution of lacZ-expressing cells and the profile of gamma-crystallin gene expression in the lenses of normal and microphthalmic offspring, the contributions of specific cell types to lens development were examined. The results suggest that phenotypically and developmentally distinct populations of lens fiber cells are able to contribute to the lens nucleus during organogenesis. We also show that dosage of the transgene and its site of integration influence the extent of ablation. In those mice homozygous for the transgene and completely lacking cells of the lens lineage, we show that the sclera, cornea, and ciliary epithelium are reduced in size but, otherwise, reasonably well formed. In contrast, the anterior chamber, iris, and vitreous body are not discernible while the sensory retina is highly convoluted and extensively fills the vitreous chamber.

Ki-67/MIB-1 and Recurrence in Pituitary Adenoma

2021 ◽  
Author(s):  
Kent Tadokoro ◽  
Colten Wolf ◽  
Joseph Toth ◽  
Cara Joyce ◽  
Meharvan Singh ◽  
...  
Keyword(s):  
Systematic Review ◽  
Pituitary Adenoma ◽  
Recurrence Rate ◽  
Pituitary Adenomas ◽  
Cellular Proliferation ◽  
Published Data ◽  
Ki 67 ◽  
Institutional Data ◽  
Mib 1

Abstract Objectives Ki-67/MIB-1 is a marker of cellular proliferation used as a pathological parameter in the clinical assessment of pituitary adenomas, where its expression has shown utility in predicting the invasiveness of these tumors. However, studies have shown variable results when using Ki-67/MIB-1 association with recurrence. The purpose of this study is to determine if a high Ki-67/MIB-1 labeling index (LI) is predictive of recurrence in pituitary adenomas. Methods A retrospective chart review was performed for patients undergoing pituitary adenoma resection with at least 1 year of follow-up. Additionally, systematic data searches were performed and included studies that correlated recurrence rate to Ki-67/MIB-1 LI. Our institutional data were included in a synthesis with previously published data. Results Our institutional review included 79 patients with a recurrence rate of 26.6%. We found that 8.8% of our patients had a high Ki-67/MIB-1 LI (>3%); however, high Ki-67/MIB-1 was not associated with recurrence. The systematic review identified 244 articles and 49 full-text articles that were assessed for eligibility. Quantitative analysis was performed on 30 articles including our institutional data and 18 studies reported recurrence by level of Ki-67/MIB-1 LI. Among studies that compared Ki-67/MIB-1 ≥3 vs. <3%, 10 studies reported odds ratios (OR) greater than 1 of which 6 were statistically significant. A high Ki-67/MIB-1 had higher odds of recurrence via the pooled odds ratio (OR = 4.15, 95% confidence interval [CI]: 2.31–7.42). Conclusion This systematic review suggests that a high Ki-67/MIB-1 should prompt an increased duration of follow-up due to the higher odds of recurrence of pituitary adenoma.

Reduction of dietary obesity in aP2-Ucp transgenic mice: physiology and adipose tissue distribution

1996 ◽  
Vol 270 (5) ◽  
pp. E768-E775 ◽  
Author(s):  
J. Kopecky ◽  
Z. Hodny ◽  
M. Rossmeisl ◽  
I. Syrovy ◽  
L. P. Kozak
Keyword(s):  
Body Weight ◽  
Adipose Tissue ◽  
Transgenic Mice ◽  
Body Weight Gain ◽  
Uncoupling Protein ◽  
Gene Promoter ◽  
Lipid Binding ◽  
Brown Fat ◽  
Mitochondrial Uncoupling ◽  
Dietary Obesity

We seek to determine whether increased energy dissipation in adipose tissue can prevent obesity. Transgenic mice with C57BL6/J background and the adipocyte lipid-binding protein (aP2) gene promoter directing expression of the mitochondrial uncoupling protein (UCP) gene in white and brown fat were used. Physiologically, UCP is essential for nonshivering thermogenesis in brown fat. Mice were assigned to a chow or a high-fat (HF) diet at 3 mo of age. Over the next 25 wk, gains of body weight were similar in corresponding subgroups (n = 6-8) of female and male mice: 4-5 g in chow nontransgenic and transgenic, 20 g in HF nontransgenic, and 9-11 g in HF transgenic mice. The lower body weight gain in the HF transgenic vs. nontransgenic mice corresponded to a twofold lower feed efficiency. Gonadal fat was enlarged, but subcutaneous white fat was decreased in the transgenic vs. nontransgenic mice in both dietary conditions. The results suggest that UCP synthesized from the aP2 gene promoter is capable of reducing dietary obesity.

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