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Journal of Fish Diseases Apr 2018Enteromyxum leei is a myxozoan parasite responsible for enteritis in gilthead sea bream (Sparus aurata). The parasite proliferates in the paracellular space of the...
Enteromyxum leei is a myxozoan parasite responsible for enteritis in gilthead sea bream (Sparus aurata). The parasite proliferates in the paracellular space of the intestinal epithelium and induces an inflammatory reaction. To assess intestinal cell turnover and parasite proliferation, fish were infected with the parasite by anal intubation; after 17 and 64 days, the cell proliferative marker bromodeoxyuridine (BrdU) was administered; and after 24 hr, tissue samples were taken for immunohistochemical detection. Parasite exposure induced increased epithelial and immune cell proliferation in all intestinal segments at all time points, even before parasite establishment. This increased turnover was triggered early after intubation and mainly at a local level, as shown by an increased proliferating cell nuclear antigen (pcna) gene expression only at the posterior intestine after 17 days (not found in lymphohaematopoietic organs). Incorporation of BrdU in parasite secondary and tertiary daughter cells indicated that parasite endogeny is not by schizogonial division, which uses de novo synthesis pathway of pyrimidines. Altogether, BrdU immunolabelling and pcna gene expression showed the rapid proliferative response of the fish intestines upon a myxozoan infection and how this response is effectively triggered even before the parasite reaches or establishes in the site.
Topics: Animals; Bromodeoxyuridine; DNA; Fish Diseases; Myxozoa; Parasitic Diseases, Animal; Sea Bream; Staining and Labeling
PubMed: 29265424
DOI: 10.1111/jfd.12765 -
Oncotarget Aug 2018High expression level of integrin α2β1 is a hallmark of prostate cancer stem cell like cells. The role of this collagen receptor is controversial since it is down...
High expression level of integrin α2β1 is a hallmark of prostate cancer stem cell like cells. The role of this collagen receptor is controversial since it is down regulated in poorly differentiated carcinomas, but concomitantly proposed to promote metastasis. Here, we show that docetaxel resistant DU145 prostate cancer cells express high levels of α2β1 and that α2β1 subpopulation of DU145 cells proliferates slower than the cells representing α2β1 subpopulation. To further study this initial observation we used Crispr/Cas9 technology to create an α2β1 negative DU145 cell line. Furthermore, we performed rescue experiment by transfecting α2 knockout cells with vector carrying α2 cDNA or with an empty vector for appropriate control. When these two cell lines were compared, α2β1 positive cells proliferated slower, were more resistant to docetaxel and also migrated more effectively on collagen and invaded faster through matrigel or collagen. Integrin α2β1 was demonstrated to be a positive regulator of p38 MAPK phosphorylation and a selective p38 inhibitor (SB203580) promoted proliferation and inhibited invasion. Effects of α2β1 integrin on the global gene expression pattern of DU145 cells in spheroid cultures were studied by RNA sequencing. Integrin α2β1 was shown to regulate several cancer progression related genes, most notably matrix metalloproteinase-1 (MMP-1), a recognized invasion promoting protein. To conclude, the fact that α2β1 decelerates cell proliferation may explain the dominance of α2β1 negative/low cells in primary sites of poorly differentiated carcinomas, while the critical role of α2β1 integrin in invasion stresses the importance of this adhesion receptor in cancer dissemination.
PubMed: 30197754
DOI: 10.18632/oncotarget.25945 -
Experimental Neurology Apr 2009One of the sexual dimorphic differences in adult rodents is neural proliferation. Here we demonstrate that physiological hormone stages can modulate this proliferation...
One of the sexual dimorphic differences in adult rodents is neural proliferation. Here we demonstrate that physiological hormone stages can modulate this proliferation in the adult forebrain. Female mice, both pregnant and synchronized in oestrus, exhibited higher proliferating cell percentages than males in both the rostral migratory stream (RMS) and the olfactory bulb (OB). Moreover, although the hormonal component also influenced the subventricular zone (SVZ), no differences in proliferation were observed in this region. In addition, both groups of females had higher numbers of serotonergic fibres in these regions. Serotonin may therefore be related to the mechanism of action by which hormones can affect cell proliferation of this brain region. We also evaluated cell death in the SVZ in males and females, finding that this was higher in the former. Taken together, our results support the idea that in female rodents more neuroblasts are able to reach the RMS and then proliferate, apoptosis being an additional mechanism affecting the low proliferation of cells in the RMS and OB in males. Thus, proliferation in the RMS is influenced by sexual dimorphism.
Topics: Analysis of Variance; Animals; Cell Movement; Cell Proliferation; Chorionic Gonadotropin; Female; Glial Fibrillary Acidic Protein; Gonadotropins, Equine; In Situ Nick-End Labeling; Lateral Ventricles; Male; Mice; Mice, Inbred C57BL; Neurons; Olfactory Bulb; Proliferating Cell Nuclear Antigen; Serotonin; Serotonin Plasma Membrane Transport Proteins; Sex Characteristics
PubMed: 19162010
DOI: 10.1016/j.expneurol.2008.12.013 -
Journal of Oral Pathology & Medicine :... Aug 2004The purpose of the present study was to elucidate whether myoepithelial cells proliferate mitotically during regeneration of rat submandibular glands after atrophy. (Comparative Study)
Comparative Study
BACKGROUND
The purpose of the present study was to elucidate whether myoepithelial cells proliferate mitotically during regeneration of rat submandibular glands after atrophy.
METHODS
The excretory duct of the right submandibular gland of rats was doubly ligated near the hilum with metal clips, which were removed after 7 days of ligation (day 0). The regenerating right submandibular glands were removed from 0 to 14 days after removal of the clips. The removed tissue was examined with immunohistochemical double staining for proliferating cell nuclear antigen (PCNA) as a marker of proliferating cells and actin as a marker of myoepithelial cells, as well as with transmission electron microscopy (TEM).
RESULTS
The PCNA-positive myoepithelial cells were observed at the periphery of transitional duct-acinar structures, ducts and acini in the regenerating glands at every time-point, and the PCNA-labeling index of myoepithelial cells increased greatly especially between day 2 and 4. The mitosis of myoepithelial cell was also identified by TEM at day 4.
CONCLUSION
These findings suggest that myoepithelial cells are able to proliferate mitotically during regeneration of rat submandibular gland.
Topics: Actins; Animals; Atrophy; Epithelial Cells; Immunoenzyme Techniques; Ligation; Male; Microscopy, Electron; Mitosis; Muscle Cells; Parotid Gland; Proliferating Cell Nuclear Antigen; Rats; Rats, Wistar; Regeneration; Salivary Ducts; Submandibular Gland
PubMed: 15250836
DOI: 10.1111/j.1600-0714.2004.00234.x -
Endocrinology Apr 1997Sex steroids control the proliferation of their target cells through two different pathways: 1) proliferative response (Step-1); and 2) inhibition of cell proliferation...
Sex steroids control the proliferation of their target cells through two different pathways: 1) proliferative response (Step-1); and 2) inhibition of cell proliferation (Step-2). Mechanisms of cell proliferation regulation are incompletely understood; however, there is general agreement with the notion that sex steroid receptors play an important role in the control of the proliferation of sex steroid target cells. To test this hypothesis, a full human androgen receptor (AR) vector was transfected into human breast cancer MCF7 cells. The cloned cells that stably express the AR, called MCF7-AR1 cells, contained approximately five times more AR than the wild-type MCF7 cells from which they were derived. These AR-transfected cells retained their capacity to proliferate when estrogens were added to 10% charcoal-dextran stripped human serum but did not acquire the ability to proliferate when androgens were added to this medium. In serumless medium (ITDME), these cells proliferated maximally, as MCF7 cells did; however, natural and synthetic androgens prevented the AR-transfected cells from proliferating. Inhibition of cell proliferation occurred when physiological androgen concentrations (1 nM) were added to ITDME; this effect was almost completely reversed by Casodex, a synthetic androgen antagonist. Under the effect of androgens added to ITDME, MCF7-AR1 cells were arrested in the G0/G1 phase within 24 h. These data suggest that: 1) the androgen-induced inhibition of cell proliferation (Step-2) is AR-mediated; and 2) the AR may be necessary, but not sufficient, to mediate the androgen-induced proliferative response (Step-1).
Topics: Androgen Antagonists; Androgens; Anilides; Blotting, Western; Breast Neoplasms; Cell Cycle; Cell Division; Dihydrotestosterone; Dose-Response Relationship, Drug; Female; Flutamide; Humans; In Vitro Techniques; Metribolone; Nandrolone; Nitriles; Receptors, Androgen; Testosterone; Testosterone Congeners; Tosyl Compounds; Transfection; Tumor Cells, Cultured
PubMed: 9075695
DOI: 10.1210/endo.138.4.5047 -
Endocrinology May 2006The ovarian surface epithelium (OSE) is a monolayer of cells that surround the ovary and accommodate repeated tear and repair in response to ovulation. OSE cells are...
The ovarian surface epithelium (OSE) is a monolayer of cells that surround the ovary and accommodate repeated tear and repair in response to ovulation. OSE cells are thought to be the progenitors of 90% of ovarian cancers. Currently, the total amount of proliferation of the OSE has not been reported in response to one ovulatory event. In this study, proliferation of the OSE was quantified in response to superovulation induced by ip injection of pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) in immature 27-d-old CD1 mice using bromodeoxyuridine (BrdU). BrdU incorporation into the OSE cells was measured from the time of hCG injection for a total cumulative label of 12 h. BrdU incorporation was also measured from the time of PMSG injection for a total label of 60 h to correlate proliferation with specific gonadotropin stimulation. The OSE proliferation was significantly higher in superovulated animals compared with control mice at all time points. Proliferation was also analyzed in discrete anatomical sections and indicated that OSE covering antral follicles and corpora lutea proliferated more rapidly than OSE distal to follicular growth. Finally, apoptosis was assessed in response to ovulation, and virtually no cell death within the OSE was detected. These data demonstrate that the OSE, especially near antral follicles and corpora lutea, proliferates significantly in response to the gonadotropins PMSG and hCG. Therefore, ovarian surface cell division in response to ovulation could contribute to ovarian cancer by proliferation-induced DNA mutations and transformed cell progression.
Topics: Animals; Apoptosis; Bromodeoxyuridine; Cell Proliferation; Corpus Luteum; Epithelial Cells; Female; Gonadotropins; Image Processing, Computer-Assisted; Immunohistochemistry; In Situ Nick-End Labeling; Mice; Models, Biological; Models, Statistical; Mutation; Ovarian Follicle; Ovary; Ovulation; Superovulation; Time Factors
PubMed: 16484319
DOI: 10.1210/en.2005-1629 -
The Journal of Veterinary Medical... Jan 2002Proliferation of chondrocytes from nucleus pulposus (NP) and anulus fibrosus (AF) was confirmed in three-dimensional culture using alginate microspheres. Cells isolated...
Proliferation of chondrocytes from nucleus pulposus (NP) and anulus fibrosus (AF) was confirmed in three-dimensional culture using alginate microspheres. Cells isolated from NP and AF were incorporated in microspheres and cultured for 14 days. Round mononuclear cells of 20-25 microm in diameter proliferated and formed aggregates. At day 14, alcian blue positive matrix surrounded the proliferating cells. The cells had cytoplasmic vacuoles stained positively by toluidine blue. On electron microscopy, the cells contained proteoglycan vacuoles and lipid droplets in the cytoplasm and synthesized collagen fibrils and electron dense granules surrounding the cell. These features of the cells were characteristic for chondrocytes. This culture system should be useful to further investigate metabolic activities of intervertebral disk chondrocytes.
Topics: Alcian Blue; Alginates; Animals; Cell Culture Techniques; Cell Division; Chondrocytes; Dog Diseases; Dogs; Female; Intervertebral Disc; Male; Microscopy, Electron; Microscopy, Phase-Contrast; Microspheres
PubMed: 11853153
DOI: 10.1292/jvms.64.79 -
American Journal of Respiratory Cell... Jun 1995Integrative gene therapy typically requires dividing cells. This requirement has been perceived as an impediment for gene transfer to mature, uninjured airways where...
Integrative gene therapy typically requires dividing cells. This requirement has been perceived as an impediment for gene transfer to mature, uninjured airways where proliferation rates are very low. In diseases such as cystic fibrosis (CF) that may be candidates for integrative gene therapy, airway cell turnover is not known but may be increased as a result of chronic inflammation. To determine if cells in airway surface epithelium and submucosal glands of CF patients proliferate at an increased rate, paraffin sections of bronchial segments removed from CF patients (n = 6) at the time of lung transplantation or rapid autopsy and from non-CF patients (n = 4) undergoing lung resection or transplantation were immunostained with PC10, a monoclonal antibody to proliferating cell nuclear antigen (PCNA), a marker of proliferating cells. The PCNA index (percentage of nuclei immunostaining for PCNA) in CF bronchial surface epithelium was 17.0 +/- 4.6% (mean +/- SEM), substantially greater than in non-CF airways (less than 0.2%). Within submucosal glands, PCNA-positive cells were more prevalent in the collecting ducts of CF patients than in those of normal subjects, but only rare mucous or serous cells were PCNA positive. These studies show that airway epithelial cell proliferation rates can be very high in inflamed CF airways. This prevalence of proliferating cells suggests that CF airway epithelium and submucosal gland ducts may be amenable to gene transfer using vectors, such as retroviruses, that require cell replication for stable integrative expression. Further studies are needed to evaluate cell proliferation in CF airways with less extensive airway injury.
Topics: Adolescent; Adult; Aged; Bronchi; Cell Division; Child; Child, Preschool; Cystic Fibrosis; Epithelium; Female; Humans; Immunohistochemistry; Male; Middle Aged; Proliferating Cell Nuclear Antigen
PubMed: 7766425
DOI: 10.1165/ajrcmb.12.6.7766425 -
Tissue & Cell Aug 2010Cell morphology and proliferation was investigated in the atretic follicles during estrous cycles in the guinea pig. Ovarian samples on days 1, 4, 8, 12 and 16 of the...
Cell morphology and proliferation was investigated in the atretic follicles during estrous cycles in the guinea pig. Ovarian samples on days 1, 4, 8, 12 and 16 of the estrous cycle in the guinea pig were taken in the morning for histologic staining with hematoxylin and eosin (HE), and immunohistochemical staining of the protein proliferating cell nuclear antigen (PCNA). The results indicated that the granulosa cells degenerated and eliminated first in atretic follicles, while the fibroblast-like cells appeared in the innermost layer of theca interna cells. When the fibroblast-like cells migrated to the antrum, they proliferated and formed a new tissue in peripheral to the zona pellucida of the oocyte. Our results also revealed that the orientation of the theca interna cell arrangement changed twice during the process of atresia, and the loose connective tissue in the antrum was critical for follicular atresia. Therefore, follicular atresia was not a simple process of cell death and elimination, but coexisted with cell proliferation. To our knowledge, we have for the first time confirmed cell proliferation and the presence of new tissue in atretic follicles in guinea pigs.
Topics: Animals; Cell Proliferation; Estrous Cycle; Female; Follicular Atresia; Guinea Pigs; Immunohistochemistry; Ovarian Follicle; Proliferating Cell Nuclear Antigen; Theca Cells
PubMed: 20605181
DOI: 10.1016/j.tice.2010.04.006 -
Journal of Cellular Physiology Jun 1991During the development of atherosclerotic and fibromuscular proliferates/lesions, smooth muscle cells (SMC) in the media, particularly near the lumen, are activated to...
During the development of atherosclerotic and fibromuscular proliferates/lesions, smooth muscle cells (SMC) in the media, particularly near the lumen, are activated to migrate into the intima, where they continue to proliferate to form an intimal thickening. It is to date unclear whether SMCs situated adjacent to the adventitia possess a lower capacity to proliferate because they are a special subpopulation of medial SMCs or because the adventitia excerts an inhibitory effect. We have, therefore, developed an in vitro system whereby we have attempted to clear up this uncertainty. The following observations were made from the in vitro experiments: Media-explants from rabbit aorta were laid on a polycarbonate filter with pores 5 microns in diameter. The SMCs migrated through the pores and formed a fibromuscular proliferate on the other side of the filter. Endothelial cells were seeded on one side of the filter before media-explants were laid on the other side of the filter. The confluent endothelium inhibited migration of SMCs through the filter pores. Media-explants were placed between two polycarbonate filters (pores 5 microns diameter). In this "sandwich" arrangement SMCs migrated through both filters, i.e., in both directions. The quantity of migrating and proliferating cells through both filters was almost identical. This suggests that there is no difference in the migratory and proliferative capacity of SMCs in the inner and outer layers in the media of arteries. To investigate the influence of the adventitia on medial SMCs, media-explants were placed between a lower (5 microns) and an upper (0.2 micron) filter. On the 0.2 micron filter adventitia-explants were laid above the media-explants. The 0.2 micron filter prevented migration of SMCs from the media-explant into the adventitia and migration of fibroblasts from the adventitia into the media. Interestingly, the adventitial tissue inhibited proliferation of SMCs at the abluminal and migration and proliferation at the luminal side of the media-explant; the number of cells migrating through the 5 microns pores at the luminal side was diminished, suggesting that the adventitial tissue has an antiproliferative influence on SMCs. Moreover, it was found that in media-explants near the filter with adventitia, the medial SMCs were in a better preserved condition than at the de-endothelialised luminal side. As a control, cultures consisting of media-explants were incubated without filters (i.e., explant organ cultures). The proliferates in the concavity (luminal side) exhibited a pattern of proliferating SMCs different from that of the cells at the abluminal convexity.(ABSTRACT TRUNCATED AT 400 WORDS)
Topics: Actins; Animals; Arteries; Bromodeoxyuridine; Cattle; Cell Communication; Cell Division; Cells, Cultured; DNA; Endothelium, Vascular; Immunohistochemistry; Male; Muscle, Smooth, Vascular; Rabbits; Swine
PubMed: 2066360
DOI: 10.1002/jcp.1041470302