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Guan L, Viswanathan V, Jiang Y, Vijayakumar S, Cao H, Zhao J, Colburg DRC, Neuhöfer P, Zhang Y, Wang J, Xu Y, Laseinde EE, Hildebrand R, Rahman M, Frock R, Kong C, Beachy PA, Artandi S, Le QT. Tert-expressing cells contribute to salivary gland homeostasis and tissue regeneration after radiation therapy. Genes Dev 2024; 38:569-582. [PMID: 38997156 PMCID: PMC11293384 DOI: 10.1101/gad.351577.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 06/25/2024] [Indexed: 07/14/2024]
Abstract
Salivary gland homeostasis and regeneration after radiotherapy depend significantly on progenitor cells. However, the lineage of submandibular gland (SMG) progenitor cells remains less defined compared with other normal organs. Here, using a mouse strain expressing regulated CreERT2 recombinase from the endogenous Tert locus, we identify a distinct telomerase-expressing (TertHigh) cell population located in the ductal region of the adult SMG. These TertHigh cells contribute to ductal cell generation during SMG homeostasis and to both ductal and acinar cell renewal 1 year after radiotherapy. TertHigh cells maintain self-renewal capacity during in vitro culture, exhibit resistance to radiation damage, and demonstrate enhanced proliferative activity after radiation exposure. Similarly, primary human SMG cells with high Tert expression display enhanced cell survival after radiotherapy, and CRISPR-activated Tert in human SMG spheres increases proliferation after radiation. RNA sequencing reveals upregulation of "cell cycling" and "oxidative stress response" pathways in TertHigh cells following radiation. Mechanistically, Tert appears to modulate cell survival through ROS levels in SMG spheres following radiation damage. Our findings highlight the significance of TertHigh cells in salivary gland biology, providing insights into their response to radiotherapy and into their use as a potential target for enhancing salivary gland regeneration after radiotherapy.
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Affiliation(s)
- Li Guan
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Vignesh Viswanathan
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Yuyan Jiang
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Sivakamasundari Vijayakumar
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Hongbin Cao
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Junfei Zhao
- Department of Pathology and Cell Biology, Columbia University, New York, New York 10032, USA
| | | | - Patrick Neuhöfer
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Yiru Zhang
- Department of Radiology, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Jinglong Wang
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Yu Xu
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Eyiwunmi E Laseinde
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Rachel Hildebrand
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Mobeen Rahman
- Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Richard Frock
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Christina Kong
- Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Philip A Beachy
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Steven Artandi
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Quynh-Thu Le
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA;
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Tessema B, Sack U, König B, Serebrovska Z, Egorov E. Effects of Intermittent Hypoxia in Training Regimes and in Obstructive Sleep Apnea on Aging Biomarkers and Age-Related Diseases: A Systematic Review. Front Aging Neurosci 2022; 14:878278. [PMID: 35677200 PMCID: PMC9168371 DOI: 10.3389/fnagi.2022.878278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/21/2022] [Indexed: 11/13/2022] Open
Abstract
Several studies have assessed the effects of intermittent hypoxia-normoxia training (IHNT), intermittent hypoxia-hyperoxia training (IHHT), and obstructive sleep apnea (OSA) on aging and age-related diseases in humans; however, the results remain contradictory. Therefore, this review aims to systematically summarize the available studies on the effects of IHNT, IHHT, and OSA on aging and age-related diseases. Relevant studies were searched from PubMed, Google Scholar, Cochrane Library databases, and through manual searching from reference lists of eligible studies. A total of 38 eligible studies were included in this systematic review. IHHT and IHNT provide positive effects on several age-related parameters including quality of life, cognitive and physical functions, plasma level of glucose and cholesterol/LDL, systolic blood pressure, red blood cells, and inflammation. Moreover, moderate intermittent hypoxia induces telomerase reverse transcriptase (TERT) activity and telomere stabilization, delays induction of senescence-associated markers expression and senescence-associated β-galactosidase, upregulates pluripotent marker (Oct4), activates a metabolic shift, and raises resistance to pro-apoptotic stimuli. On the contrary, intermittent hypoxia in OSA causes hypertension, metabolic syndrome, vascular function impairment, quality of life and cognitive scores reduction, advanced brain aging, increase in insulin resistance, plasma hydrogen peroxide, GSH, IL-6, hsCRP, leptin, and leukocyte telomere shortening. Thus, it can be speculated that the main factor that determines the direction of the intermittent hypoxia action is the intensity and duration of exposure. There is no direct study to prove that IHNT/IHHT actually increases life expectancy in humans. Therefore, further study is needed to investigate the actual effect of IHNT/IHHT on aging in humans.Systematic Review Registrationwww.crd.york.ac.uk/prospero, identifier CRD42022298499.
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Affiliation(s)
- Belay Tessema
- Institute of Clinical Immunology, Faculty of Medicine, Leipzig University, Leipzig, Germany
- Institute of Medical Microbiology and Epidemiology of Infectious Diseases, Faculty of Medicine, Leipzig University, Leipzig, Germany
- Department of Medical Microbiology, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
- *Correspondence: Belay Tessema, ,
| | - Ulrich Sack
- Institute of Clinical Immunology, Faculty of Medicine, Leipzig University, Leipzig, Germany
| | - Brigitte König
- Institute of Medical Microbiology and Epidemiology of Infectious Diseases, Faculty of Medicine, Leipzig University, Leipzig, Germany
| | - Zoya Serebrovska
- Department of General and Molecular Pathophysiology, Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Egor Egorov
- IPAM Institute for Preventive and Anti-Aging Medicine, Berlin, Germany
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TELOMERASE MEDIATEDS PYROPTOSIS BY NF-κB Chicken telomerase reverse transcriptase mediates LMH cell pyroptosis by regulating the nuclear factor-kappa B signaling pathway. Poult Sci 2022; 101:101826. [PMID: 35385822 PMCID: PMC9170928 DOI: 10.1016/j.psj.2022.101826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 11/23/2021] [Accepted: 02/23/2022] [Indexed: 11/21/2022] Open
Abstract
The activation of human telomerase reverse transcriptase is regulated by the nuclear factor kappa B (NF-κB) signaling pathway to various degrees to promote the occurrence and development of tumors. However, the regulatory roles of chicken telomerase reverse transcriptase (chTERT) and the NF-κB signaling pathway in chickens are still elusive, particularly in respect to the regulation of cell pyroptosis. In this study, we found that chTERT upregulated the expression of p65 and p50, downregulated the expression of IκBα, promoted the phosphorylation of p65, p50, and IκBα, and significantly increased the transcript levels of the inflammatory cytokines IFNγ, TNFα, and IL-6 in LMH cells. The activity of NF-κB was significantly decreased after siRNA-mediated chTERT silencing. The expression of chTERT and telomerase activity were also significantly decreased when the NF-κB signaling pathway was blocked by p65 siRNA, MG132 or BAY 11-7082. In cells treated with LPS, the activity of NF-κB signaling pathway and the expression of chTERT were significantly upregulated. All of the results suggested that chTERT and the NF-κB pathway could regulate each other, reciprocally. Moreover, the expression of Caspase-1, NLRP3, GSDMA, IL-18, and IL-1β and caused membrane perforation, suggesting the development of pyroptosis by chTERT in LMH cells. And the expression of caspase-11 did not significantly increased in chTERT overexpression group. Genetic silence of NF-κB p65 or chTERT gene by siRNA suppressed the expression of these proinflammatory cytokines, indicating that chTERT mediates pyroptosis by regulating the NF-κB signaling pathway in LMH cells.
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Turkiewicz S, Ditmer M, Sochal M, Białasiewicz P, Strzelecki D, Gabryelska A. Obstructive Sleep Apnea as an Acceleration Trigger of Cellular Senescence Processes through Telomere Shortening. Int J Mol Sci 2021; 22:12536. [PMID: 34830418 PMCID: PMC8624921 DOI: 10.3390/ijms222212536] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 01/10/2023] Open
Abstract
Obstructive sleep apnea (OSA) is chronic disorder which is characterized by recurrent pauses of breathing during sleep which leads to hypoxia and its two main pathological sequelae: oxidative stress and chronic inflammation. Both are also associated with cellular senescence. As OSA patients present with higher prevalence of age-related disorders, such as atrial hypertension or diabetes mellitus type 2, a relationship between OSA and accelerated aging is observable. Furthermore, it has been established that these OSA are associated with telomere shortening. This process in OSA is likely caused by increased oxidative DNA damage due to increased reactive oxygen species levels, DNA repair disruptions, hypoxia, chronic inflammation, and circadian clock disturbances. The aim of the review is to summarize study outcomes on changes in leukocyte telomere length (LTL) in OSA patients and describe possible molecular mechanisms which connect cellular senescence and the pathophysiology of OSA. The majority of OSA patients are characterized by LTL attrition due to oxidative stress, hypoxia and inflammation, which make a kind of positive feedback loop, and circadian clock disturbance.
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Affiliation(s)
- Szymon Turkiewicz
- Department of Sleep Medicine and Metabolic Disorders, Medical University of Lodz, 92-215 Lodz, Poland; (S.T.); (M.D.); (M.S.); (P.B.)
| | - Marta Ditmer
- Department of Sleep Medicine and Metabolic Disorders, Medical University of Lodz, 92-215 Lodz, Poland; (S.T.); (M.D.); (M.S.); (P.B.)
| | - Marcin Sochal
- Department of Sleep Medicine and Metabolic Disorders, Medical University of Lodz, 92-215 Lodz, Poland; (S.T.); (M.D.); (M.S.); (P.B.)
| | - Piotr Białasiewicz
- Department of Sleep Medicine and Metabolic Disorders, Medical University of Lodz, 92-215 Lodz, Poland; (S.T.); (M.D.); (M.S.); (P.B.)
| | - Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Lodz, 92-215 Lodz, Poland;
| | - Agata Gabryelska
- Department of Sleep Medicine and Metabolic Disorders, Medical University of Lodz, 92-215 Lodz, Poland; (S.T.); (M.D.); (M.S.); (P.B.)
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A Beginner's Introduction to Skin Stem Cells and Wound Healing. Int J Mol Sci 2021; 22:ijms222011030. [PMID: 34681688 PMCID: PMC8538579 DOI: 10.3390/ijms222011030] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/06/2021] [Accepted: 10/11/2021] [Indexed: 02/06/2023] Open
Abstract
The primary function of the skin is that of a physical barrier against the environment and diverse pathogens; therefore, its integrity is essential for survival. Skin regeneration depends on multiple stem cell compartments within the epidermis, which, despite their different transcriptional and proliferative capacity, as well as different anatomical location, fall under the general term of skin stem cells (SSCs). Skin wounds can normally heal without problem; however, some diseases or extensive damage may delay or prevent healing. Non-healing wounds represent a serious and life-threatening scenario that may require advanced therapeutic strategies. In this regard, increased focus has been directed at SSCs and their role in wound healing, although emerging therapeutical approaches are considering the use of other stem cells instead, such as mesenchymal stem cells (MSCs). Given its extensive and broad nature, this review supplies newcomers with an introduction to SSCs, wound healing, and therapeutic strategies for skin regeneration, thus familiarizing the reader with the subject in preparation for future in depth reading.
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Gong C, Yang H, Wang S, Liu J, Li Z, Hu Y, Chen Y, Huang Y, Luo Q, Wu Y, Liu E, Xiao Y. hTERT Promotes CRC Proliferation and Migration by Recruiting YBX1 to Increase NRF2 Expression. Front Cell Dev Biol 2021; 9:658101. [PMID: 34079797 PMCID: PMC8165255 DOI: 10.3389/fcell.2021.658101] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/12/2021] [Indexed: 12/14/2022] Open
Abstract
High human telomerase reverse transcriptase (hTERT) expression is related to severe Colorectal Cancer (CRC) progression and negatively related to CRC patient survival. Previous studies have revealed that hTERT can reduce cancer cellular reactive oxygen species (ROS) levels and accelerate cancer progression; however, the mechanism remains poorly understood. NFE2-related factor 2 (NRF2) is a molecule that plays a significant role in regulating cellular ROS homeostasis, but whether there is a correlation between hTERT and NRF2 remains unclear. Here, we showed that hTERT increases CRC proliferation and migration by inducing NRF2 upregulation. We further found that hTERT increases NRF2 expression at both the mRNA and protein levels. Our data also revealed that hTERT primarily upregulates NRF2 by increasing NRF2 promoter activity rather than by regulating NRF2 mRNA or protein stability. Using DNA pull-down/MS analysis, we found that hTERT can recruit YBX1 to upregulate NRF2 promoter activity. We also found that hTERT/YBX1 may localize to the P2 region of the NRF2 promoter. Taken together, our results demonstrate that hTERT facilitates CRC proliferation and migration by upregulating NRF2 expression through the recruitment of the transcription factor YBX1 to activate the NRF2 promoter. These results provide a new theoretical basis for CRC treatment.
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Affiliation(s)
- Chunli Gong
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Huan Yang
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Sumin Wang
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Jiao Liu
- Department of Endoscope, General Hospital of Shenyang Military Region, Shenyang, China
| | - Zhibin Li
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yiyang Hu
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yang Chen
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yu Huang
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Qiang Luo
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yuyun Wu
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - En Liu
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yufeng Xiao
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
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Yao D, GangYi Y, QiNan W. Autophagic dysfunction of β cell dysfunction in type 2 diabetes, a double-edged sword. Genes Dis 2020; 8:438-447. [PMID: 34179308 PMCID: PMC8209341 DOI: 10.1016/j.gendis.2020.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 03/07/2020] [Accepted: 03/12/2020] [Indexed: 12/19/2022] Open
Abstract
Diabetes is an age-related disease, most of which is type 2 diabetes, and islet β cell dysfunction and insulin resistance are the main mechanisms of type 2 diabetes. Recent studies have revealed that autophagy plays an important role in maintaining the structure and function of islet beta cells and inhibiting insulin resistance and apoptosis induced by oxidative stress. In this review, we discussed the positive and negative effects of autophagy and its dysfunction on type 2 diabetes mellitus, which is the so-called double-edged sword, analysed its possible mechanism, and identified possible research hot spots.
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Affiliation(s)
- Ding Yao
- Endocrinology and Nephrology Department, Chongqing University Cancer Hospital and Chongqing Cancer Institute and Chongqing Cancer Hospital, Chongqing, 400030, PR China
| | - Yang GangYi
- Endocrinology Department, The Second Affiliated Hospital of the Chongqing Medical University, Chongqing, 400010, PR China
| | - Wu QiNan
- Endocrinology and Nephrology Department, Chongqing University Cancer Hospital and Chongqing Cancer Institute and Chongqing Cancer Hospital, Chongqing, 400030, PR China
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The Potential Role of Cycloastragenol in Promoting Diabetic Wound Repair In Vitro. BIOMED RESEARCH INTERNATIONAL 2019; 2019:7023950. [PMID: 31930133 PMCID: PMC6939423 DOI: 10.1155/2019/7023950] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 11/29/2019] [Indexed: 12/17/2022]
Abstract
Background Refractory wound healing is a severe complication of diabetes with a significant socioeconomic burden. Whereas current therapies are insufficient to accelerate repair, stem cell-based therapy is increasingly recognized as an alternative that improves healing outcomes. The aim of the present study is to explore the role of cycloastragenol (CAG), a naturally occurring compound in Astragali Radix, in ameliorating refractory cutaneous wound healing in vitro, which may provide a new insight into therapeutic strategy for diabetic wounds. Methods Human epidermal stem cells (EpSCs) obtained from nine patients were exposed to CAG, with or without DKK1 (a Wnt signaling inhibitor). A lentiviral short hairpin RNA (shRNA) system was used to establish the telomerase reverse transcriptase (TERT) and β-catenin knockdown cell line. Cell counting kit-8, scratch wound healing, and transwell migration assay were used to determine the effects of CAG in cell growth and migration. The activation of TERT, β-catenin, and c-Myc was determined using real-time qPCR and western blot analysis. Chromatin immunoprecipitation (ChIP) was performed to evaluate the associations among CAG, TERT, and Wnt/β-catenin signals. Results CAG not only promoted the proliferation and migration ability of EpSCs but also increased the expression levels of TERT, β-catenin, c-Myc. These effects of CAG were most pronounced at a dose of 0.3 μM. Notably, the CAG-promoted proliferative and migratory abilities of EpSCs were abrogated in TERT and β-catenin-silenced cells. In addition, the ChIP results strongly suggested that CAG-modulated TERT was closely associated with the activation of Wnt/β-catenin signaling. Conclusion Our data indicate that CAG is a TERT activator of EpSCs and is associated with their proliferation and migration, a role it may play through the activation of Wnt/β-catenin signaling.
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Hu Z, Zhou S, Luo H, Ji M, Zheng J, Huang F, Wang F. miRNA-17 promotes nasopharyngeal carcinoma radioresistance by targeting PTEN/AKT. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2019; 12:229-240. [PMID: 31933738 PMCID: PMC6944021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 11/23/2018] [Indexed: 06/10/2023]
Abstract
Radioresistance remains a challenge during nasopharyngeal carcinoma (NPC) radiotherapy. Numerous studies suggest that the miRNAs may play important roles in the regulation of radioresistance. miRNA-17-5p, which is located within the miR-17-92a cluster, could modulate tumor progression in different tissues by targeting multiple tumor associated genes. However, whether it is correlated with the radioresistance of tumor cells has not yet been elucidated. In our study, we have observed increasing miR-17-5p expression in radioresistant NPC tissues. The functional experiments suggested that miR-17-5p could clearly promote NPC cell proliferation and the cell cycle even after X-ray irradiation. Irradiation leads to tumor cell damage and death via ROS generation. The overexpression of miR-17-5p could protect NPC cells from apoptosis induced by irradiation. In addition, an in vivo experiment indicated that miR-17-5p promoted tumor growth with radiotherapy using the xenograft tumor model. A bioinformatics analysis and reporter assay were carried out to demonstrate that PTEN, which is a key regulator of AKT phosphorylation, is a target of miR-17-5p. The overexpression of miR-17-5p directly suppresses the mRNA and protein expression of PTEN. In addition, the rescue experiments showed that the AKT inhibitor can diminish the proliferation, promotion, and apoptosis inhibition effects on radioresistant NPC cells mediated by miR-17-5p. In conclusion, our findings demonstrated that miR-17-5p can enhance the radioresistance of NPC through the PTEN/AKT pathway, which is a biomarker of radioresistant NPC and a potential target for new therapeutic strategies.
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Affiliation(s)
- Zhiqiang Hu
- Department of Ear, Nose and Throat Diseases, 906 Hospital of PLANingbo, Zhejiang, China
| | - Subo Zhou
- Department of Ear, Nose and Throat Diseases, 906 Hospital of PLANingbo, Zhejiang, China
| | - Hengdan Luo
- Department of Ear, Nose and Throat Diseases, 906 Hospital of PLANingbo, Zhejiang, China
| | - Miao Ji
- Department of Ear, Nose and Throat Diseases, 906 Hospital of PLANingbo, Zhejiang, China
| | - Jianliang Zheng
- Department of Ear, Nose and Throat Diseases, 906 Hospital of PLANingbo, Zhejiang, China
| | - Fei Huang
- Department of Stomatology, No. 6 Medical Center of PLA General HospitalBeijing, China
| | - Feng Wang
- Department of Stomatology, No. 6 Medical Center of PLA General HospitalBeijing, China
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Han Z, Li Q, Sun S, Zhao W, Shi L. Inactivated Sendai virus strain Tianjin induces apoptosis and autophagy through reactive oxygen species production in osteosarcoma MG-63 cells. J Cell Physiol 2018; 234:4179-4190. [PMID: 30146726 DOI: 10.1002/jcp.27176] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/17/2018] [Indexed: 12/20/2022]
Abstract
Sendai virus strain Tianjin, a novel genotype of Sendai virus, has been proven to possess potent antitumor effect on certain cancer cell types although inactivated by ultraviolet (UV). This study was carried out to investigate the in vitro anticancer properties of UV-inactivated Sendai virus strain Tianjin (UV-Tianjin) on human osteosarcoma cells and the underlying molecular mechanism. Our studies demonstrated UV-Tianjin significantly inhibited the viability of human osteosarcoma cell lines and triggered apoptosis through activation of both extrinsic and intrinsic pathways in MG-63 cells. Meanwhile, autophagy occurred in UV-Tianjin-treated cells. Blockade of autophagy with 3-methyladenine remarkably attenuated the inhibition of cell proliferation by UV-Tianjin, suggesting that UV-Tianjin-induced autophagy may be contributing to cell death. Furthermore, UV-Tianjin induced reactive oxygen species (ROS) production, which was involved in the execution of MG-63 cell apoptosis and autophagy, as evidenced by the result that treatment of N-acetyl-L-cysteine, a ROS scavenger, attenuated both apoptosis and autophagy. In addition, inhibition of apoptosis promoted autophagy, whereas suppression of autophagy attenuated apoptosis. Our results suggest that UV-Tianjin triggers apoptosis and autophagic cell death via generation of the ROS in MG-63 cells, which might provide important insights into the effectiveness of novel strategies for osteosarcoma therapy.
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Affiliation(s)
- Zhe Han
- Department of Orthopedics, Tianjin hospital, Tianjin, China.,Department of Pathogenic Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Qing Li
- Department of Pathogenic Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Shuya Sun
- Department of Pathogenic Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Wei Zhao
- Department of Emergency & General Department, Stomatological Hospital of Tianjin Medical University, Tianjin, China
| | - Liying Shi
- Department of Pathogenic Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
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11
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Jiang LB, Cao L, Ma YQ, Chen Q, Liang Y, Yuan FL, Li XL, Dong J, Chen N. TIGAR mediates the inhibitory role of hypoxia on ROS production and apoptosis in rat nucleus pulposus cells. Osteoarthritis Cartilage 2018; 26:138-148. [PMID: 29061494 DOI: 10.1016/j.joca.2017.10.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2017] [Revised: 10/07/2017] [Accepted: 10/11/2017] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Hypoxia has been shown to inhibit reactive oxygen species (ROS) production in nucleus pulposus (NP) cells. The TP53-induced glycolysis and apoptosis regulator (TIGAR) has been reported to suppress oxidative stress. We sought to explore the role of TIGAR in the effect of hypoxia on ROS production and apoptosis. METHODS An intervertebral disc degeneration (IDD) model of Sprague-Dawley (SD) rat caudal spine was established by puncturing the Co6-7 disc. TIGAR expression was detected by immunohistochemistry and western blotting in human and SD rat NP tissues of degenerated discs. Rat primary NP cells treated with hypoxia and cobalt chloride (CoCl2) were analyzed by western blotting for TIGAR expression. After TIGAR silence with TIGAR siRNA transfection, apoptosis percentage, mitochondrial and total intracellular ROS levels were measured. H2O2 was used to further check the effects of TIGAR on oxidative stress. Finally, NADPH/NADP+ and GSH/GSSH ratio were examined after TIGAR silencing under hypoxic conditions and after H2O2 treatment. RESULTS A degree-dependent increase in TIGAR expression was observed in human and rat degenerated NP tissues. Hypoxia and hypoxia-inducer CoCl2 enhanced TIGAR and P53 expressions in rat NP cells. TIGAR silence reversed the inhibitory effects of hypoxia on intracellular and mitochondrial ROS production, as well as apoptosis percentage. However, TIGAR silence aggravated H2O2-induced ROS production. In addition, TIGAR increased NADPH/NADP+ and GSH/GSSH ratio in NP cells. CONCLUSIONS These results suggested that TIGAR appears to mediate the protective role of hypoxia on ROS production and apoptosis percentage by enhancing NADPH/NADP+ and GSH/GSSH ratio.
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Affiliation(s)
- L-B Jiang
- Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - L Cao
- Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Y-Q Ma
- Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Q Chen
- Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Y Liang
- Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - F-L Yuan
- Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - X-L Li
- Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China.
| | - J Dong
- Department of Orthopedic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China.
| | - N Chen
- Department of Orthopedic Surgery, Zhongshan Hospital, Qingpu Branch, Fudan University, Shanghai, China.
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Digital gene expression analysis of Takifugu rubripes brain after acute hypoxia exposure using next-generation sequencing. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2017; 24:12-18. [DOI: 10.1016/j.cbd.2017.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 03/07/2017] [Accepted: 05/27/2017] [Indexed: 01/21/2023]
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Qin H, Xu HZ, Gong YQ. Mechanism of NF-κB signaling pathway and autophagy in the regulation of osteoblast differentiation. Mol Membr Biol 2017; 33:138-144. [PMID: 29166808 DOI: 10.1080/09687688.2017.1400601] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The objective of the present work was to investigate a possible mechanism of NF-κB signaling pathway and autophagy in the regulation of osteoblast differentiation, and provide experimental basis for the study of tooth eruption disorder. METHODS Mouse osteoblast-like (MC3T3-E1) cells were inoculated with a cell density of 70%. According to the grouping experimental design, Western blot and monodansylcadaverine (MDC) detection were conducted after dosing for 24 h. The cells were divided into the following five groups: blank control group; 6.25 µg/mL SN50 group; 12.5 µg/mL SN50 group; 25 µg/mL SN50 group and 50 µg/mL SN50 group. RESULTS Western blot analysis revealed that the expression of LC3 protein was present in the blank control group; 6.25 µg/mL SN50 group; 12.5 µg/mL SN50 group and 50 µg/mL SN50 group, with no significant differences among these groups. However, the expression of LC3 protein was significantly lower in the 25 µg/mL SN50 group. MDC detection showed that, in the blank control group; 6.25 µg/mL SN50 group; 12.5 µg/mL SN50 group and 50 µg/mL SN50 group, there was obvious green fluorescence in the cytoplasm of the osteoblasts. However, in the 25 µg/mL SN50 group, it was found that there were significantly fewer green fluorescent particles. CONCLUSION The osteoblast itself had a strong function of autophagy. The appropriate concentration of SN50 in blocking the NF-κB pathway of the osteoblast was associated with the obvious inhibition of autophagy. However, the relationship between NF-κB signaling pathway and autophagy in the process of tooth eruption requires further study.
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Affiliation(s)
- Han Qin
- a Department of Stomatology , Lianyungang Affiliated Hospital of Xuzhou Medical University , Liangyungang , Jiangsu Province , China
| | - Hong-Zhi Xu
- a Department of Stomatology , Lianyungang Affiliated Hospital of Xuzhou Medical University , Liangyungang , Jiangsu Province , China
| | - Yong-Qing Gong
- a Department of Stomatology , Lianyungang Affiliated Hospital of Xuzhou Medical University , Liangyungang , Jiangsu Province , China
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Wang R, Shen Z, Yang L, Yin M, Zheng W, Wu B, Liu T, Song H. Protective effects of heme oxygenase-1-transduced bone marrow-derived mesenchymal stem cells on reduced‑size liver transplantation: Role of autophagy regulated by the ERK/mTOR signaling pathway. Int J Mol Med 2017; 40:1537-1548. [PMID: 28901391 PMCID: PMC5627878 DOI: 10.3892/ijmm.2017.3121] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 08/21/2017] [Indexed: 12/17/2022] Open
Abstract
Autophagy is a critical lysosomal pathway that degrades cytoplasmic components to maintain cell homeostasis and provide substrates for energy metabolism. A study revealed that heme oxygenase-1 (HO-1)-transduced bone marrow-derived mesenchymal stem cells (BM-MSCs) could protect 50% reduced-size liver transplantation (RSLT) in a rat model. However, the mechanisms remain mostly unknown. The aim of the present study was to explore the effects and related mechanism of autophagy on the protection conferred by HO-1-transduced BM-MSCs (HO-1/BM-MSCs) on 50% RSLT in a rat model. The authors established an acute rejection model following 50% RSLT in rats, with recipients divided into three groups receiving treatment with BM-MSCs, HO-1/BM-MSCs or normal saline (NS) injected through the dorsal penile vein. Transplanted liver tissues at 0, 1, 3, 5, 7, 10 and 14 days following transplantation were acquired for further analysis. The results indicated that the expression of autophagy-related proteins LC3 and Beclin-1 increased, the levels of ERK and p-ERK increased, and the levels of mammalian target of rapamycin (mTOR) and p-mTOR decreased in the HO-1/BM-MSCs. These observations indicated that autophagy is involved in the protective effects of HO-1/BM-MSCs on liver grafts following RSLT, possibly via upregulation of autophagy-related proteins through the ERK/mTOR signaling pathway.
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Affiliation(s)
- Raorao Wang
- Tianjin First Central Hospital Clinic Institute, Tianjin Medical University, Tianjin 300070, P.R. China
| | - Zhongyang Shen
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
| | - Liu Yang
- Tianjin First Central Hospital Clinic Institute, Tianjin Medical University, Tianjin 300070, P.R. China
| | - Mingli Yin
- Tianjin First Central Hospital Clinic Institute, Tianjin Medical University, Tianjin 300070, P.R. China
| | - Weiping Zheng
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
| | - Bin Wu
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
| | - Tao Liu
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
| | - Hongli Song
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
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l -carnitine preserves cardiac function by activating p38 MAPK/Nrf2 signalling in hearts exposed to irradiation. Eur J Pharmacol 2017; 804:7-12. [DOI: 10.1016/j.ejphar.2017.04.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 03/29/2017] [Accepted: 04/05/2017] [Indexed: 01/31/2023]
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Chen X, Wang P, Guo F, Wang X, Wang J, Xu J, Yuan D, Zhang J, Shao C. Autophagy enhanced the radioresistance of non-small cell lung cancer by regulating ROS level under hypoxia condition. Int J Radiat Biol 2017; 93:764-770. [PMID: 28463025 DOI: 10.1080/09553002.2017.1325025] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PURPOSE Tumor resistance towards radiation has been a big obstacle in the poor prognosis of lung cancer. It has been reported that hypoxia and autophagy partly contribute to this resistance. However, there is controversy over whether autophagy plays a positive role in cancer therapy or not. We aim to find out the specific mechanism of radiation resistance. MATERIALS AND METHODS A549 cells were treated with conditioned medium (CM) under 12 h hypoxia or normoxia before irradiation, followed by the measurement of clonogenic survival, reactive oxygen species (ROS), signal of mitochondria and autophagy flux. In some experiments, the A549 cells were respectively transfected with LC3 small interfering RNA (siRNA), or treated with Earle's Balanced Salt Solution (EBSS). RESULTS We found that hypoxia enhanced cell radioresistance by increasing the induction of autophagy. And after hypoxia stress, the number of mitochondria was reduced but the cellular ROS level was enhanced. It was significant that autophagy may enhance cell radioresistance by reducing ROS during hypoxic treatment. CONCLUSIONS We elucidated the possible mechanisms of autophagy in regulating cancer cell death or survival. These results supply a new opinion about the intrinsic factor of radioresistance of hypoxia tumors.
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Affiliation(s)
- Xiaoyan Chen
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
| | - Ping Wang
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
| | - Fei Guo
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
| | - Xiangdong Wang
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
| | - Juan Wang
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
| | - Jinping Xu
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
| | - Dexiao Yuan
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
| | - Jianghong Zhang
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
| | - Chunlin Shao
- a Institute of Radiation Medicine , Fudan University , Shanghai , China
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Liu Q, Guan JZ, Sun Y, Le Z, Zhang P, Yu D, Liu Y. Insulin-like growth factor 1 receptor-mediated cell survival in hypoxia depends on the promotion of autophagy via suppression of the PI3K/Akt/mTOR signaling pathway. Mol Med Rep 2017; 15:2136-2142. [PMID: 28260056 PMCID: PMC5364871 DOI: 10.3892/mmr.2017.6265] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 12/15/2016] [Indexed: 12/14/2022] Open
Abstract
Hypoxia is widely accepted as a fundamental biological phenomenon, which is strongly associated with tissue damage and cell viability under stress conditions. Insulin-like growth factor-1 (IGF-1) is known to protect tissues from multiple types of damage, and protect cells from apoptosis. Hypoxia is a regulatory factor of the IGF system, however the role of the IGF-1 receptor (IGF-1R) in hypoxia-induced apoptosis remains unclear. The present study investigated the potential mechanisms associated with IGF-1R-associated apoptosis under hypoxic conditions. Mouse embryonic fibroblasts exhibiting disruption or overexpression of IGF-1R (R- cells and R+ cells) were used to examine the level of apoptosis, autophagy, and production of reactive oxygen species (ROS). The autophagy inhibitor 3-methyladenine was used to assess the effect of autophagy on ROS production and apoptosis under hypoxic conditions. A potential downstream signaling pathway involving phosphatidylinositol 3-kinase (PI3K)/threonine protein kinase B (Akt)/mammalian target of rapamycin (mTOR) was identifiedby western blot analysis. The results demonstrated that hypoxia induced apoptosis, increased ROS production, and promoted autophagy in a time-dependent manner relative to that observed under normoxia. R+ cells exhibited a lower percentage of apoptotic cells, lower ROS production, and higher levels of autophagy when compared to that of R- cells. In addition, inhibition of autophagy led to increased ROS production and a higher percentage of apoptotic cells in the two cell types. Furthermore, IGF-1R is related with PI3K/Akt/mTOR signaling pathway and enhanced autophagy-associated protein expression, which was verified following treatment with the PI3K inhibitor LY294002. These results indicated that IGF-1R may increase cell viability under hypoxic conditions by promoting autophagy and scavenging ROS production, which is closed with PI3K/Akt/mTOR signaling pathway.
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Affiliation(s)
- Qi Liu
- Cancer Research Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China
| | - Jing-Zhi Guan
- Department of Oncology, The People's Liberation Army No. 309 Hospital, Beijing 100193, P.R. China
| | - Yong Sun
- Cancer Research Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China
| | - Ziyu Le
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, P.R. China
| | - Ping Zhang
- Cancer Research Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China
| | - Dong Yu
- School of Radiological Medicine and Protection, Medical College of Soochow University, Soochow University, Suzhou, Jiangsu 215123, P.R. China
| | - Yong Liu
- Cancer Research Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, P.R. China
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Meng JJ, Li SP, Zhao FY, Tong Y, Mu DZ, Qu Y. [Effect of telomerase activation on biological behaviors of neural stem cells in rats with hypoxic-ischemic insults]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2017; 19:229-236. [PMID: 28202125 PMCID: PMC7389468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 12/08/2016] [Indexed: 11/12/2023]
Abstract
OBJECTIVE To investigate the effect of telomerase activation on biological behaviors of neural stem cells after hypoxic-ischemic insults. METHODS The neural stem cells passaged in vitro were divided into four groups: control, oxygen-glucose deprivation (OGD), OGD+cycloastragenol (CAG) high concentration (final concentration of 25 μM), and OGD+CAG low concentration (final concentration of 10 μM). The latter three groups were subjected to OGD. Telomerase reverse transcriptase (TERT) expression level was evaluated by Western blot. Telomerase activity was detected by telomerase repeat amplification protocol (TRAP). Cell number and neural sphere diameter were measured under a microscope. The activity of lactate dehydrogenase (LDH) was examined by chemiluminescence. Cell proliferation rate and apoptosis were detected by flow cytometry. RESULTS After OGD insults, obvious injury of neural stem cells was observed, including less cell number, smaller neural sphere, more dead cells, lower proliferation rate and decreased survival rate. In CAG-treated groups, there were higher TERT expression level and telomerase activity compared with the control group (P<0.05). In comparison with the OGD group, CAG treatment attenuated cell loss (P<0.05) and neural sphere diameter decrease (P<0.05), promoted cell proliferation (P<0.05), and increased cell survival rate (P<0.05). Low and high concentrations of CAG had similar effects on proliferation and survival of neural stem cells (P>0.05). In the normal cultural condition, CAG treatment also enhanced TERT expression (P<0.05) and increased cell numbers (P<0.05) and neural sphere diameter (P<0.05) compared with the control group. CONCLUSIONS Telomerase activation can promote the proliferation and improve survival of neural stem cells under the state of hypoxic-ischemic insults, suggesting telomerase activators might be potential agents for the therapy of hypoxic-ischemic brain injury.
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Affiliation(s)
- Jun-Jie Meng
- Department of Pediatrics, West China Second University Hospital, Sichuan University/Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education/Key Laboratory of Development and Related Diseases of Women and Children, Chengdu 610041, China.
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Meng JJ, Li SP, Zhao FY, Tong Y, Mu DZ, Qu Y. [Effect of telomerase activation on biological behaviors of neural stem cells in rats with hypoxic-ischemic insults]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2017; 19:229-236. [PMID: 28202125 PMCID: PMC7389468 DOI: 10.7499/j.issn.1008-8830.2017.02.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 12/08/2016] [Indexed: 06/06/2023]
Abstract
OBJECTIVE To investigate the effect of telomerase activation on biological behaviors of neural stem cells after hypoxic-ischemic insults. METHODS The neural stem cells passaged in vitro were divided into four groups: control, oxygen-glucose deprivation (OGD), OGD+cycloastragenol (CAG) high concentration (final concentration of 25 μM), and OGD+CAG low concentration (final concentration of 10 μM). The latter three groups were subjected to OGD. Telomerase reverse transcriptase (TERT) expression level was evaluated by Western blot. Telomerase activity was detected by telomerase repeat amplification protocol (TRAP). Cell number and neural sphere diameter were measured under a microscope. The activity of lactate dehydrogenase (LDH) was examined by chemiluminescence. Cell proliferation rate and apoptosis were detected by flow cytometry. RESULTS After OGD insults, obvious injury of neural stem cells was observed, including less cell number, smaller neural sphere, more dead cells, lower proliferation rate and decreased survival rate. In CAG-treated groups, there were higher TERT expression level and telomerase activity compared with the control group (P<0.05). In comparison with the OGD group, CAG treatment attenuated cell loss (P<0.05) and neural sphere diameter decrease (P<0.05), promoted cell proliferation (P<0.05), and increased cell survival rate (P<0.05). Low and high concentrations of CAG had similar effects on proliferation and survival of neural stem cells (P>0.05). In the normal cultural condition, CAG treatment also enhanced TERT expression (P<0.05) and increased cell numbers (P<0.05) and neural sphere diameter (P<0.05) compared with the control group. CONCLUSIONS Telomerase activation can promote the proliferation and improve survival of neural stem cells under the state of hypoxic-ischemic insults, suggesting telomerase activators might be potential agents for the therapy of hypoxic-ischemic brain injury.
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Affiliation(s)
- Jun-Jie Meng
- Department of Pediatrics, West China Second University Hospital, Sichuan University/Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education/Key Laboratory of Development and Related Diseases of Women and Children, Chengdu 610041, China.
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