scholarly journals Ultrastructural study of proliferating cells with an improved immunocytochemical detection of DNA-incorporated bromodeoxyuridine.

1995 ◽  
Vol 43 (1) ◽  
pp. 21-29 ◽  
Author(s):  
R Tamatani ◽  
Y Taniguchi ◽  
Y Kawarai
Keyword(s):  
Ultrastructural Study ◽  
Staining Method ◽  
Improved Method ◽  
Proliferating Cells ◽  
Gold Particles ◽  
Immunocytochemical Detection ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation ◽  
Silver Staining Method ◽  
Incorporated Brdu

We designed an improved method to observe proliferating cells with well-preserved ultrastructure. After IP injection of bromodeoxyuridine (BrdU) into rats, the pituitaries were fixed in 4% paraformaldehyde with 0.05% or 0.2% glutaraldehyde and post-fixed with ferrocyanide-reduced osmium. They were embedded in LR White and polymerized by heat. BrdU incorporated into DNA was detected with a commercial anti-BrdU monoclonal antibody (MAb) by the immunogold or the immunogold-silver staining method. Using these methods, proliferating cells labeled by BrdU were observed with well-preserved ultrastructure. By light microscopy, the number of labeled cells was almost the same regardless of the fixative used. By electron microscopy, localization of gold particles that indicate incorporated BrdU varied according to the cells and was mainly observed in two patterns, one in which gold particles were localized in condensed chromatin scattered in the nucleus and the other in which gold particles were dispersed evenly all over the nucleus. These results showed that with our improved method fine ultrastructure and good immunoreactivity of BrdU can be obtained in proliferating cells. We consider that this method is very useful for ultrastructural study of cell proliferation and differentiation.

Contrasting patterns of c-myc and N-myc expression in proliferating, quiescent, and differentiating cells of the embryonic chicken lens

Development ◽  
1992 ◽  
Vol 115 (3) ◽  
pp. 813-820
Author(s):  
L.L. Harris ◽  
J.C. Talian ◽  
P.S. Zelenka
Keyword(s):  
Cell Proliferation ◽  
Protein Product ◽  
Mrna Levels ◽  
Lens Fiber ◽  
Proliferating Cells ◽  
Fiber Cells ◽  
Embryonic Chicken ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation

The present study uses the polymerase chain reaction and in situ hybridization to examine c-myc and N-myc mRNA in the embryonic chicken lens at 6, 10, 14 and 19 days of development and compares the pattern of expression obtained with the developmental pattern of cell proliferation and differentiation. In the central epithelium, c-myc mRNA levels were proportional to the percentage of proliferating cells throughout development. N-myc mRNA expression in this region was relatively low and showed no correlation with cell proliferation. The ratio of N-myc to c-myc mRNA increased markedly with the onset of epithelial cell elongation and terminal fiber cell differentiation, although both c-myc and N-myc mRNAs continued to be expressed in postmitotic, elongating cells of the equatorial epithelium and in terminally differentiating lens fiber cells. Thus, increased expression of N-myc, a gene whose protein product may compete with c-myc protein for dimerization partners, accompanies the dissociation of c-myc expression and cell proliferation during terminal differentiation of lens fiber cells.

scholarly journals Subcellular Localization of Prolyl Endopeptidase During the First Wave of Rat Spermatogenesis and in Rat and Human Sperm

2018 ◽  
Vol 67 (4) ◽  
pp. 229-243 ◽  
Author(s):  
Massimo Venditti ◽  
Sergio Minucci
Keyword(s):  
Sertoli Cells ◽  
Cognitive Disorders ◽  
Human Sperm ◽  
Prolyl Endopeptidase ◽  
Peptidase Activity ◽  
Female Reproduction ◽  
Proliferating Cells ◽  
Cell Proliferation And Differentiation ◽  
Potential Association ◽  
Proliferation And Differentiation

Prolyl endopeptidase (PREP) is an enzyme which cleaves several peptide hormones and neuropeptides on the carboxyl side of proline residues and is involved in many biological processes, including cell proliferation and differentiation, glucose metabolism, learning, memory, and cognitive disorders. PREP has also been identified as a binding partner of tubulin, suggesting the involvement of endopeptidase in microtubule-associate processes, independent of its peptidase activity. Furthermore, several reports have implied PREP participation in both male and female reproduction-associated mechanism. We herein assess a potential association of PREP to the morphogenesis of rat testis, profiling its localization versus tubulin, during the first wave of spermatogenesis and in the adult gonad (from 7 to 60 dpp). We show that, in mitotic phases, PREP shares its localization with tubulin in Sertoli cells, gonocytes, and spermatogonia. Later, during meiosis, both proteins are found in spermatocytes, and in the cytoplasm of Sertoli cells protrusions, surrounding the germ cells, while, during spermiogenesis, they both localize in the cytoplasm of round and elongating spermatids. We also found that this enzyme has a peculiar nuclear localization, in the proliferating cells in all phases of analysis. Finally, they are expressed in the flagellum of mature gametes, as corroborated by additional immunolocalization analysis on both rat and human sperm. Our data support the hypothesis of the fundamental role of PREP in reproduction and in cytoskeletal organization during mammalian testis morphogenesis and gamete progression.

scholarly journals Immunogold-silver staining method for light and electron microscopic detection of lymphocyte cell surface antigens with monoclonal antibodies.

1990 ◽  
Vol 38 (8) ◽  
pp. 1215-1221 ◽  
Author(s):  
Y Otsuki ◽  
L E Maxwell ◽  
S Magari ◽  
H Kubo
Keyword(s):  
Electron Microscopy ◽  
Monoclonal Antibodies ◽  
Staining Method ◽  
Surface Antigens ◽  
Cell Surfaces ◽  
Cell Surface Antigens ◽  
Gold Particles ◽  
Silver Staining Method ◽  
Lymphocyte Cell ◽  
Physical Developer

We used the immunogold-silver staining method (IGSS) for detection of lymphocyte cell surface antigens with monoclonal antibodies in light and electron microscopy and compared this procedure with the immunogold staining method. Two different sizes of colloidal gold particles (5 nm and 15 nm) were used in this study. Immunolabeling on cell surfaces was visualized as fine granules only by IGSS in light microscopy. The labeling density (silver-gold complexes/cell) and diameters of silver-enhanced gold particles on cell surfaces were examined by electron microscopy. Labeling density was influenced not by the enhancement time of the physical developer but by the size of the gold particles. However, the development of shells of silver-enhanced gold particles correlated with the enhancement time of the physical developer rather than the size of the colloidal gold particles. Five-nm gold particles enhanced with the physical developer for 3 min were considered optimal for this IGSS method because of reduced background staining and high specific staining in the cell suspensions in sheep lymph. Moreover, this method may make it possible to show the ultrastructure of identical positive cells detected in 1-micron sections counterstained with toluidine blue by electron microscopy, in addition to the percentage of positive cells by light microscopy.

scholarly journals QUANTITATIVE ANALYSIS OF CELL PROLIFERATION AND DIFFERENTIATION IN THE CORTEX OF THE POSTNATAL MOUSE CEREBELLUM

1967 ◽  
Vol 32 (2) ◽  
pp. 277-287 ◽  
Author(s):  
Setsuya Fujita
Keyword(s):  
Granular Layer ◽  
Molecular Layer ◽  
External Granular Layer ◽  
Proliferating Cells ◽  
Daily Production ◽  
Cell Proliferation And Differentiation ◽  
Matrix Cell ◽  
Proliferation And Differentiation ◽  
Before And After ◽  
Mantle Layer

The generation cycle of germinative cells (external matrix cells) in the external granular layer of the cerebellar cortex of the 10-to 11-day-old mouse was studied by radioautography following repeated injections of H3-thymidine. The generation time is 19 hr, presynthetic time 8.5 hr, DNA-synthetic time 8 hr, postsynthetic time 2 hr, and mitotic time 0.5 hr. These proliferating cells occupy the outer half of the external granular layer and make up the external matrix layer. Neuroblasts are differentiated from the external matrix cell, migrate out from the layer and accumulate in the inner half of the external granular layer to form the external mantle layer. The transit time of the neuroblasts in the external mantle layer is 28 hr. Thereafter, they migrate farther into the molecular layer and the internal granular layer. By means of long-term cumulative labeling, the rate of daily production of neuroblasts from the external matrix cell is studied in quantitative terms. It becomes clear that the entire population of the inner granule neurons arises postnatally in the external granular layer between 1 and 18 days of age and that 95% of them is produced between postnatal days 4 and 15. Finally, the fate of the cells in the external granular layer at its terminal stage was studied by marking the cells with H3-thymidine during 15–16 days of life and following their subsequent migration and developmental changes up to 21 days of life. Comparison of radioautographs taken before and after the migration disclosed that the external matrix cells give rise to a small number of neuroglia cells. This finding revealed their multipotential nature.

Role of melatonin in regulating neurogenesis: Implications for the neurodegenerative pathology and analogous therapeutics for Alzheimer’s disease

2020 ◽  
Vol 3 (2) ◽  
pp. 216-242 ◽  
Author(s):  
Mayuri Shukla ◽  
Areechun Sotthibundhu ◽  
Piyarat Govitrapong
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Adult Neurogenesis ◽  
Adult Brain ◽  
Therapeutic Approaches ◽  
Therapeutic Implications ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation ◽  
Progenitor Cell Proliferation

The revelation of adult brain exhibiting neurogenesis has established that the brain possesses great plasticity and that neurons could be spawned in the neurogenic zones where hippocampal adult neurogenesis attributes to learning and memory processes. With strong implications in brain functional homeostasis, aging and cognition, various aspects of adult neurogenesis reveal exuberant mechanistic associations thereby further aiding in facilitating the therapeutic approaches regarding the development of neurodegenerative processes in Alzheimer’s Disease (AD). Impaired neurogenesis has been significantly evident in AD with compromised hippocampal function and cognitive deficits. Melatonin the pineal indolamine augments neurogenesis and has been linked to AD development as its levels are compromised with disease progression. Here, in this review, we discuss and appraise the mechanisms via which melatonin regulates neurogenesis in pathophysiological conditions which would unravel the molecular basis in such conditions and its role in endogenous brain repair. Also, its components as key regulators of neural stem and progenitor cell proliferation and differentiation in the embryonic and adult brain would aid in accentuating the therapeutic implications of this indoleamine in line of prevention and treatment of AD.   

Icariin Stimulates hFOB 1.19 Osteoblast Proliferation and Differentiation via OPG/RANKL Mediated by the Estrogen Receptor

2020 ◽  
Vol 22 (1) ◽  
pp. 168-175 ◽  
Author(s):  
Lin-Jun Sun ◽  
Chong Li ◽  
Xiang-hao Wen ◽  
Lu Guo ◽  
Zi-Fen Guo ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Estrogen Receptor ◽  
Protein Expression ◽  
Chinese Herb ◽  
Human Osteoblast ◽  
Osteoblast Cells ◽  
Expression Ratio ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation ◽  
Mrna And Protein Expression

Background:: Icariin (ICA), one of the main effective components isolated from the traditional Chinese herb Epimedium brevicornu Maxim., has been reported to possess extensive pharmacological actions, including enhanced sexual function, immune regulation, anti-inflammation, and antiosteoporosis. Methods:: Our study was designed to investigate the effect of ICA on cell proliferation and differentiation and the molecular mechanism of OPG/RANKL mediated by the Estrogen Receptor (ER) in hFOB1.19 human osteoblast cells. Results:: The experimental results show that ICA can stimulate cell proliferation and increase the activity of Alkaline Phosphatase (ALP), Osteocalcin (BGP) and I Collagen (Col I) and a number of calcified nodules. Furthermore, the mRNA and protein expression of OPG and RANKL and the OPG/ RANKL mRNA and protein expression ratios were upregulated by ICA. The above-mentioned results indicated that the optimal concentration of ICA for stimulating osteogenesis was 50ng/mL. Subsequent mechanistic studies comparing 50ng/mL ICA with an estrogen receptor antagonist demonstrated that the effect of the upregulated expression is connected with the estrogen receptor. In conclusion, ICA can regulate bone formation by promoting cell proliferation and differentiation and upregulating the OPG/RANKL expression ratio by the ER in hFOB1.19 human osteoblast cells.

MicroRNA Determines the Fate of Intestinal Epithelial Cell Differentiation and Regulates Intestinal Diseases

2019 ◽  
Vol 20 (7) ◽  
pp. 666-673 ◽  
Author(s):  
Sujuan Ding ◽  
Gang Liu ◽  
Hongmei Jiang ◽  
Jun Fang
Keyword(s):  
Target Genes ◽  
Gastrointestinal Disease ◽  
Intestinal Barrier ◽  
Vital Role ◽  
Intestinal Barrier Function ◽  
Intestinal Epithelial ◽  
Intestinal Function ◽  
Cell Fates ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation

The rapid self-renewal of intestinal epithelial cells enhances intestinal function, promotes the nutritional needs of animals and strengthens intestinal barrier function to resist the invasion of foreign pathogens. MicroRNAs (miRNAs) are a class of short-chain, non-coding RNAs that regulate stem cell proliferation and differentiation by down-regulating hundreds of conserved target genes after transcription via seed pairing to the 3' untranslated regions. Numerous studies have shown that miRNAs can improve intestinal function by participating in the proliferation and differentiation of different cell populations in the intestine. In addition, miRNAs also contribute to disease regulation and therefore not only play a vital role in the gastrointestinal disease management but also act as blood or tissue biomarkers of disease. As changes to the levels of miRNAs can change cell fates, miRNA-mediated gene regulation can be used to update therapeutic strategies and approaches to disease treatment.

scholarly journals Regulation of Metabolic Reprogramming by Long Non-Coding RNAs in Cancer

Cancers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 3485
Author(s):  
Assunta Sellitto ◽  
Giovanni Pecoraro ◽  
Giorgio Giurato ◽  
Giovanni Nassa ◽  
Francesca Rizzo ◽  
...  
Keyword(s):  
Lipid Metabolism ◽  
Cancer Cells ◽  
Metabolic Reprogramming ◽  
Metabolic Phenotype ◽  
Metabolic Alterations ◽  
Cell Proliferation And Differentiation ◽  
Non Coding Rna ◽  
Proliferation And Differentiation ◽  
Non Coding Rnas ◽  
Additional Level

Metabolic reprogramming is a well described hallmark of cancer. Oncogenic stimuli and the microenvironment shape the metabolic phenotype of cancer cells, causing pathological modifications of carbohydrate, amino acid and lipid metabolism that support the uncontrolled growth and proliferation of cancer cells. Conversely, metabolic alterations in cancer can drive changes in genetic programs affecting cell proliferation and differentiation. In recent years, the role of non-coding RNAs in metabolic reprogramming in cancer has been extensively studied. Here, we review this topic, with a focus on glucose, glutamine, and lipid metabolism and point to some evidence that metabolic alterations occurring in cancer can drive changes in non-coding RNA expression, thus adding an additional level of complexity in the relationship between metabolism and genetic programs in cancer cells.

scholarly journals Signal-mediated nuclear transport in proliferating and growth-arrested BALB/c 3T3 cells.

1991 ◽  
Vol 115 (4) ◽  
pp. 933-939 ◽  
Author(s):  
C M Feldherr ◽  
D Akin
Keyword(s):  
High Cell Density ◽  
Unit Length ◽  
3T3 Cells ◽  
Proliferating Cells ◽  
Gold Particles ◽  
Nuclear Uptake ◽  
Large Particles ◽  
The Mean ◽  
Transport Channels ◽  
Relative Uptake

Mediated transport across the nuclear envelope was investigated in proliferating and growth-arrested (confluent or serum starved) BALB/c 3T3 cells by analyzing the nuclear uptake of nucleoplasmin-coated colloidal gold after injection into the cytoplasm. Compared with proliferating cells the nuclear uptake of large gold particles (110-270 A in diameter, including the protein coat) decreased 5.5-, 33-, and 78-fold, respectively, in 10-, 14-17-, and 21-d-old confluent cultures; however, the relative uptake of small particles (total diameter 50-80 A) did not decrease with increasing age of the cells. This finding suggests that essentially all pores remain functional in confluent populations, but that most pores lose their capacity to transport large particles. By injecting intermediate-sized gold particles, the functional diameters of the transport channels in the downgraded pores were estimated to be approximately to 130 and 110 A, in 14-17- and 21-d-old cultures, respectively. In proliferating cells, the transport channels have a functional diameter of approximately 230 A. The mean diameters of the pores (membrane-to-membrane distance) in proliferating and confluent cells (728 and 712 A, respectively) were significantly different at the 10%, but not the 5%, level. No differences in pore density (pore per unit length of membrane) were detected. Serum-deprived cells (7-8 d in 1% serum or 4 d in 0.5% serum) also showed a significant decrease in the nuclear uptake of large, but not small, gold particles. Thus, the permeability effects are not simply a function of high cell density but appear to be growth related. The possible functional significance of these findings is discussed.

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