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Frontiers in Neuroscience 2020Astrocytes exhibit a region-dependent molecular and functional heterogeneity in the CNS. Although cortical astrocytes proliferate robustly during the first postnatal...
Astrocytes exhibit a region-dependent molecular and functional heterogeneity in the CNS. Although cortical astrocytes proliferate robustly during the first postnatal week and become proliferation quiescent, the temporal proliferation dynamics of astrocytes in subcortical regions during postnatal development remain essentially unknown. Whether subcortical astrocytes mature similarly to cortical astrocytes is also unexplored. In this current study, we examined proliferation of subcortical, especially hypothalamic, astrocytes during postnatal development using genetic labeling of astrocytes and pulse-chase EdU labeling of proliferating cells. While a lower number of proliferating astrocytes was found in the hypothalamus compared to cortex during the first postnatal week, astrocyte proliferation is much more active in hypothalamus than in cortex from P15 to P30 in both proliferating astrocyte density and percentage, indicating a persistent and distinct proliferation pattern of astrocytes in hypothalamus. This observation is further confirmed by Ki67 immunostaining with genetically or immunolabeled astrocytes in hypothalamus and cortex during P15-30. In addition, astrocytes in representative subcortical regions have a modest growth of their domain size and exhibit a significantly smaller domain size compared to cortical astrocytes at P30 when astrocytes have generally completed postnatal maturation. However, the expression of astrocyte-derived Sparc, an important synaptogenic inhibitor, is consistently higher in hypothalamic astrocytes than in cortical astrocytes throughout postnatal development. In summary, our study unveiled a distinct proliferation and maturation pattern of subcortical, especially hypothalamic, astrocytes during postnatal development.
PubMed: 32457572
DOI: 10.3389/fnins.2020.00435 -
Experimental Cell Research Mar 2020The cardiac and skeletal muscle tissues are both striated and contractile but their intrinsic cellular properties are distinct. The minimal cardiomyocyte proliferation...
The cardiac and skeletal muscle tissues are both striated and contractile but their intrinsic cellular properties are distinct. The minimal cardiomyocyte proliferation and the lack of cardiac stem cells directly leads to poor heart repair in adult mammals. But in skeletal muscle, the robust proliferation of widespread muscle stem cells support efficient muscle regeneration. The endogenous cardiomyocyte and muscle stem cell proliferation has been analyzed in common laboratory animals but not in large mammals including pigs, which are more comparable to human. In this study, we rigorously examined the cell cycle dynamics of porcine cardiomyocytes and muscle stem cells through different developmental stages. Proliferative cardiomyocytes and muscle stem cells were broadly observed in the embryonic heart and limb muscle respectively. Muscle stem cells continue to proliferate postnatally but cardiomyocyte proliferation was drastically reduced after birth. However, robust cardiomyocyte cell cycle activity was detected around postnatal day 20, which could be attributed to the binucleation but not cell division. Increased proliferating cells were detected in maternal heart during early pregnancy but they represent non-cardiomyocyte cell types. The islet1 expressing cells were only identified in the embryonic and new born porcine hearts. Furthermore, the accumulated oxidative DNA damage in the cardiac but not skeletal muscle during development could be responsible for the diminished cardiomyocyte proliferation in adult pig. Similarities and differences in the proliferation of heart and skeletal muscle cells are identified in pigs across different developmental stages. Such cellular proliferative features must be taken into account when using porcine models for cardiovascular and muscular research.
Topics: Animals; Animals, Newborn; Cell Cycle; Cell Proliferation; Cells, Cultured; Female; Gene Expression Regulation, Developmental; Heart; Muscle, Skeletal; Myocytes, Cardiac; Organogenesis; Pregnancy; Regeneration; Stem Cells; Swine
PubMed: 31954694
DOI: 10.1016/j.yexcr.2020.111854 -
Journal of Applied Physiology... Oct 2018In asthma, it is unclear if the airway smooth muscle cells proliferate more or are increased at the onset of asthma and remain stable. This study aimed to compare smooth...
In asthma, it is unclear if the airway smooth muscle cells proliferate more or are increased at the onset of asthma and remain stable. This study aimed to compare smooth muscle cell proliferation in individuals with and without asthma and correlate proliferation rates with cell size and number and with granulocytic airway inflammation. Postmortem airway sections were labeled with proliferating cell nuclear antigen (PCNA) and percent positive muscle cells calculated. On the same sections, smooth muscle cell size and number and the number of eosinophils and neutrophils were estimated and compared in cases of nonfatal ( n = 15) and fatal ( n = 15) asthma and control subjects ( n = 15). The %PCNA muscle cells was not significantly different in fatal (29.4 ± 7.7%, mean ± SD), nonfatal asthma (28.6 ± 8.3%), or control subjects (24.6 ± 6.7%) and not related to mean muscle cell size ( r = 0.09), number ( r = 0.36), thickness of the muscle layer ( r = 0.05), or eosinophil numbers ( r = 0.04) in the asthma cases. These data support the hypothesis that in asthma the increased thickness of the smooth muscle layer may be present before or at the onset of asthma and independent of concurrent granulocytic inflammation or exacerbation. NEW & NOTEWORTHY There is debate regarding the origins of the increased airway smooth muscle in asthma. It may be independent of inflammation or arise as a proliferative response to inflammation. The present study found no increase in the proportion of proliferating smooth muscle cells in asthma and no relation of proliferation to numbers of airway smooth muscle cells or inflammation. These results support a stable increase in smooth muscle in asthma that is independent of airway inflammation.
Topics: Adolescent; Adult; Asthma; Bronchi; Case-Control Studies; Cell Proliferation; Female; Humans; Inflammation; Male; Muscle, Smooth; Myocytes, Smooth Muscle; Young Adult
PubMed: 30024335
DOI: 10.1152/japplphysiol.00342.2018 -
Current Medicinal Chemistry 2015Mitochondria are responsible for coordinating cellular energy production in the vast majority of somatic cells, and every cell type in a specific state can have a... (Review)
Review
Mitochondria are responsible for coordinating cellular energy production in the vast majority of somatic cells, and every cell type in a specific state can have a distinct metabolic signature. The metabolic requirements of cells from different tissues changes as they proliferate/differentiate, and cellular metabolism must match these demands. Proliferating cells, namely cancer cells and stem cells, tend to prefer glycolysis rather than a more oxidative metabolism. This preference has been exploited for the improvement of new biotechnological and therapeutic applications. In this review, we describe mitochondrial dynamics and energy metabolism modulation during nuclear reprogramming of somatic cells, which will be essential for the development and optimization of new protocols for regenerative medicine, disease modeling and toxicological screens involving patient-specific reprogrammed cells.
Topics: Animals; Cell Proliferation; Cellular Reprogramming; Humans; Mitochondria; Neoplasms; Stem Cells
PubMed: 25973982
DOI: 10.2174/0929867322666150514095718 -
Indian Journal of Dermatology,... 2023Syringocystadenoma papilliferum is a benign adnexal neoplasm. Contiguous squamous proliferation has been rarely described in syringocystadenoma papilliferum.
BACKGROUND
Syringocystadenoma papilliferum is a benign adnexal neoplasm. Contiguous squamous proliferation has been rarely described in syringocystadenoma papilliferum.
AIMS
This study aimed to evaluate the spectrum and pathogenesis of contiguous squamous proliferation in syringocystadenoma papilliferum.
MATERIALS AND METHODS
All cases of syringocystadenoma papilliferum diagnosed over the past 12 years were screened for contiguous squamous proliferation. Cases with associated nevus sebaceous were excluded from the study. Immunohistochemistry for GATA3, CK7, BRAFV600E and p16 was performed. PCR for human papilloma virus, type 16 and 18, was carried out.
RESULTS
Of a total of 30 cases, 14 cases showed associated contiguous squamous proliferation which included four cases of verrucous hyperplasia, six cases with papillomatosis, two cases with mild squamous hyperplasia and one case each of Bowen's disease and squamous cell carcinoma. In the cases with non-neoplastic contiguous squamous proliferations, the squamous component did not express CK7 or GATA3. However, the squamous component of premalignant and malignant lesions expressed CK7 and GATA3 concordant with the adenomatous component. BRAF was positive in adenomatous component in five cases while the contiguous squamous proliferation component was negative for BRAF in all but one case. p16 was negative in both components of all cases and PCR for human papilloma virus was negative in all cases.
LIMITATIONS
Due to the rarity of disease, the sample size of our study was relatively small with two cases in the 2nd group, that is, syringocystadenoma papilliferum with malignant contiguous squamous proliferation. Detailed molecular studies such as gene sequencing were not performed.
CONCLUSION
Syringocystadenoma papilliferum with contiguous squamous proliferation is underreported, and most commonly displays verrucous hyperplasia. The premalignant and malignant contiguous squamous proliferations likely arise from syringocystadenoma papilliferum while the hyperplastic contiguous squamous proliferations likely arise from the adjacent epidermis. Relationship with high-risk human papilloma virus is unlikely. However, further molecular analysis of larger number of cases is required to establish the pathogenesis.
Topics: Humans; Tubular Sweat Gland Adenomas; Sweat Gland Neoplasms; Retrospective Studies; Proto-Oncogene Proteins B-raf; Hyperplasia; Carcinoma, Squamous Cell
PubMed: 34623039
DOI: 10.25259/IJDVL_845_20 -
European Journal of Histochemistry : EJH Oct 2023Cholangiocytes, the epithelial cells that line the biliary tree, can proliferate under the stimulation of several factors through both autocrine and paracrine pathways....
Cholangiocytes, the epithelial cells that line the biliary tree, can proliferate under the stimulation of several factors through both autocrine and paracrine pathways. The cocaine-amphetamine-regulated-transcript (CART) peptide has several physiological functions, and it is widely expressed in several organs. CART increases the survival of hippocampal neurons by upregulating brain-derived neurotrophic factor (BDNF), whose expression has been correlated to the proliferation rate of cholangiocytes. In the present study, we aimed to evaluate the expression of CART and its role in modulating cholangiocyte proliferation in healthy and bile duct ligated (BDL) rats in vivo, as well as in cultured normal rat cholangiocytes (NRC) in vitro. Liver samples from both healthy and BDL (1 week) rats, were analyzed by immunohistochemistry and immunofluorescence for CART, CK19, TrkB and p75NTR BDNF receptors. PCNA staining was used to evaluate the proliferation of the cholangiocytes, whereas TUNEL assay was used to evaluate biliary apoptosis. NRC treated or not with CART were used to confirm the role of CART on cholangiocytes proliferation and the secretion of BDNF. Cholangiocytes proliferation, apoptosis, CART and TrkB expression were increased in BDL rats, compared to control rats. We found a higher expression of TrkB and p75NTR, which could be correlated with the proliferation rate of biliary tree during BDL. The in vitro study demonstrated increased BDNF secretion by NRC after treatment with CART compared with control cells. As previously reported, proliferating cholangiocytes acquire a neuroendocrine phenotype, modulated by several factors, including neurotrophins. Accordingly, CART may play a key role in the remodeling of biliary epithelium during cholestasis by modulating the secretion of BDNF.
Topics: Animals; Rats; Bile Ducts; Brain-Derived Neurotrophic Factor; Cell Proliferation; Epithelium; Nerve Tissue Proteins
PubMed: 37859350
DOI: 10.4081/ejh.2023.3846 -
Animals : An Open Access Journal From... Jul 2022The E2F family of transcription factor is divided into activators and repressors that control cell proliferation. Bovine mammary epithelial cells (BMECs) can be...
The E2F family of transcription factor is divided into activators and repressors that control cell proliferation. Bovine mammary epithelial cells (BMECs) can be immortalized using human papillomavirus 16 E6E7 (HPV16 E6E7) and simian vacuolating virus 40 large T antigen (SV40T). In addition, SV40T does not require E2F1, E2F2, and E2F3 activators to induce proliferation in mouse embryo fibroblasts (MEFs). However, we report that E2F3 activator is required to induce the proliferation of BMECs. Our results showed that, at an early stage, primary BMECs lacking the E2F1 expression have the capacity to proliferate and show E2F2 and E2F3 slight protein levels. At a late stage, primary BMECs deficient for E2F3 completely abolish any proliferative ability and exhibit a severe cell senescence signal, although the E2F2 can be expressed at a late stage of primary BMECs. Compared with the late stage of primary BMECs, the BMECs immortalized by SV40T and E6E7 restored the protein level of E2F3 and enhanced the CDK4, CDK6, cyclin D3, and CDK2 protein level, leading to proliferating robustly. Surprisingly, it was found that p53, p21, and p27 were upregulated in SV40T and E6E7-immortalized BMECs, relatively to primary BMECs. Notably, Cdc2 was almost expressed in primary BMECs. However, Cdc2 was elevated in BMECs immortalized by SV40T and E6E7. In conclusion, this study revealed a molecular mechanism where E2F3 controls the BMECs' proliferation and senescence.
PubMed: 35883337
DOI: 10.3390/ani12141790 -
Medical Archives (Sarajevo, Bosnia and... Aug 2021Recent advances in stem cell technologies have rekindled an interest in the use of cell therapies to treat patients with Parkinson's disease. Although the...
BACKGROUND
Recent advances in stem cell technologies have rekindled an interest in the use of cell therapies to treat patients with Parkinson's disease. Although the transplantation of dopaminergic mesencephalic human fetal brain tissue has previously been reported in the treatment of patients with Parkinson's disease, this method is limited by the availability of tissue obtained from each human embryo.
OBJECTIVE
Our study aimed to isolate, culture, proliferate, and differentiate dopaminergic neurons from human neuroepithelial stem cells obtained from embryo reduction procedures performed in multifetal pregnancies following in vitro fertilization.
MATERIALS AND METHODS
A total of 201 human embryos were dissected for isolation and culture of neuroepithelial stem cells for proliferation and differentiation into dopaminergic neurons. All embryos were obtained from embryo reduction procedures performed in multifetal pregnancies after in vitro fertilization treatments.
RESULTS
Human neuroepithelial stem cells were isolated and cultured from embryos from 6.0 to 8.0 weeks. Neuroepithelial stem cells were successfully isolated, proliferated, and differentiated into dopaminergic neurons. The cells adhered to the surfaces of cell culture plates after 2 days and could be proliferated and differentiated into neurons within 4 days. Cultured cells expressed the dopaminergic marker tyrosine hydroxylase after 6 days, suggesting that these cells were successfully differentiated into dopaminergic neurons.
CONCLUSION
The successful isolation, culture, proliferation, and differentiation of human dopaminergic neurons from embryo reductions performed for multifetal pregnancies after in vitro fertilization suggests that this pathway may serve as a potential source of cell therapy materials for use in the treatment of Parkinson's disease.
Topics: Cell Differentiation; Cell Proliferation; Cells, Cultured; Dopaminergic Neurons; Female; Fertilization in Vitro; Humans; Pregnancy; Pregnancy Reduction, Multifetal; Stem Cells
PubMed: 34759448
DOI: 10.5455/medarh.2021.75.280-285 -
Frontiers in Cell and Developmental... 2022Stem Leydig cells (SLCs) play a critical role in the development and maintenance of the adult Leydig cell (ALC) population. SLCs also are present in the adult testis....
Stem Leydig cells (SLCs) play a critical role in the development and maintenance of the adult Leydig cell (ALC) population. SLCs also are present in the adult testis. Their identification, characteristics, and regulation in the adult testis remain uncertain. Using single-cell RNA-seq, we found that the mesenchymal stromal population may be involved in ALC regeneration. Upon ALC elimination, a fraction of stromal cells begins to proliferate while a different fraction begins to differentiate to ALCs. Transcriptomic analysis identified five stromal clusters that can be classified into two major groups representing proliferation and differentiation populations. The proliferating group represents stem cells expressing high levels of CD90, Nes, Lum, Fn and Gap43. The differentiating group represents a progenitor stage that is ready to form ALCs, and specifically expresses Vtn, Rasl11a, Id1 and Egr2. The observation that the actively dividing cells after ALC loss were not those that formed ALCs suggests that stem cell proliferation and differentiation are regulated separately, and that the maintenance of the stromal stem cell pool occurs at the population level. The study also identified specific markers for the major interstitial cell groups and potential paracrine factors involved in the regulation of SLCs. Our data suggest a new theory about SLC identity, proliferation, differentiation, and regulation.
PubMed: 35242757
DOI: 10.3389/fcell.2022.805249 -
Frontiers in Immunology 2019The location of coelomocyte proliferation in adult sea urchins is unknown and speculations since the early 1800s have been based on microanatomy and tracer uptake...
The location of coelomocyte proliferation in adult sea urchins is unknown and speculations since the early 1800s have been based on microanatomy and tracer uptake studies. In adult sea urchins () with down-regulated immune systems, coelomocyte numbers increase in response to immune challenge, and whether some or all of these cells are newly proliferated is not known. The gene regulatory network that encodes transcription factors that control hematopoiesis in embryonic and larval sea urchins has not been investigated in adults. Hence, to identify the hematopoietic tissue in adult sea urchins, cell proliferation, expression of phagocyte specific genes, and expression of genes encoding transcription factors that function in the conserved regulatory network that controls hematopoiesis in embryonic and larval sea urchins were investigated for several tissues. Cell proliferation was induced in adult sea urchins either by immune challenge through injection of heat-killed or by cell depletion through aspiration of coelomic fluid. In response to either of these stimuli, newly proliferated coelomocytes constitute only about 10% of the cells in the coelomic fluid. In tissues, newly proliferated cells and cells that express SpTransformer proteins (formerly Sp185/333) that are markers for phagocytes are present in the axial organ, gonad, pharynx, esophagus, and gut with no differences among tissues. The expression level of genes encoding transcription factors that regulate hematopoiesis show that both the axial organ and the pharynx have elevated expression compared to coelomocytes, esophagus, gut, and gonad. Similarly, an RNAseq dataset shows similar results for the axial organ and pharynx, but also suggests that the axial organ may be a site for removal and recycling of cells in the coelomic cavity. Results presented here are consistent with previous speculations that the axial organ may be a site of coelomocyte proliferation and that it may also be a center for cellular removal and recycling. A second site, the pharynx, may also have hematopoietic activity, a tissue that has been assumed to function only as part of the intestinal tract.
Topics: Animals; Cell Proliferation; Hematopoiesis; Immune System; Phagocytes; Pharynx; Sea Urchins; Transcription Factors; Vibrio
PubMed: 31105697
DOI: 10.3389/fimmu.2019.00870