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1.
Nucleic Acids Res ; 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32112110

RESUMO

The genetic etiology of premature ovarian insufficiency (POI) has been well established to date, however, the role of long noncoding RNAs (lncRNAs) in POI is largely unknown. In this study, we identified a down-expressed lncRNA HCP5 in granulosa cells (GCs) from biochemical POI (bPOI) patients, which impaired DNA damage repair and promoted apoptosis of GCs. Mechanistically, we discovered that HCP5 stabilized the interaction between YB1 and its partner ILF2, which could mediate YB1 transferring into the nucleus of GCs. HCP5 silencing affected the localization of YB1 into nucleus and reduced the binding of YB1 to the promoter of MSH5 gene, thereby diminishing MSH5 expression. Taken together, we identified that the decreased expression of HCP5 in bPOI contributed to dysfunctional GCs by regulating MSH5 transcription and DNA damage repair via the interaction with YB1, providing a novel epigenetic mechanism for POI pathogenesis.

2.
Cell Death Dis ; 11(2): 107, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034125

RESUMO

Mouse embryonic stem cells (ESCs) are isolated from the inner cell mass of blastocysts, and they exist in different states of pluripotency-naïve and primed states. Pten is a well-known tumor suppressor. Here, we generated Pten-/- mouse ESCs with the CRISPR-Cas9 system and verified that Pten-/- ESCs maintained naïve pluripotency by blocking Gsk3ß activity. Serum/LIF and 2i (MAPK and GSK3 inhibitors) conditions are commonly used for ESC maintenance. We show that the Pten-inhibitor SF1670 contributed to sustaining mouse ESCs and that Pten activation by the S380A, T382A, and T383A mutations (Pten-A3) suppressed the pluripotency of ESCs. The in vivo teratoma formation ability of SF1670-treated ESCs increased, while the Pten-A3 mutations suppressed teratoma formation. Furthermore, the embryoid bodies derived from Pten-deficient ESCs or SF1670-treated wild-type ESCs showed greater expression of ectoderm and pluripotency markers. These results suggest that Pten-mediated Gsk3ß modulates the naïve pluripotency of ESCs and that Pten ablation regulates the lineage-specific differentiation.

3.
Am J Reprod Immunol ; 83(4): e13220, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31925865

RESUMO

PROBLEM: For women of reproductive age, achieving a successful pregnancy requires both the normal functioning of reproductive endocrine and the health of the reproductive tract environment. We aimed to study how these fertility factors, such as female age, baseline sexual hormone levels, tubal patency, and vaginal pH, affect the composition of vaginal microbiome. METHOD OF STUDY: The 16S rRNA sequencing was carried on vaginal microbiome samples from 85 women of reproductive age without vaginal infections or reproductive endocrine diseases. The detailed correlations between fertility factors and vaginal microbiome were quantified by Spearman's rank tests. A linear discriminant analysis was carried out to explore the effects of fertility factors on the relative abundances of vaginal bacterial species. RESULTS: The vaginal pH, levels of basal E2, LH, and FSH all had significant effects on the distribution of vaginal microbiome. The relative abundances of vaginal bacterial species, including Escherichia coli, Streptococcus agalactiae, and Prevotella intermedia, were significantly different due to the host's state of reproductive endocrine and tubal patency. It was worth noting that women with tubal obstruction, or prolonged menstrual cycle, or antral follicle count >15, or vaginal pH > 4.5 all had a higher abundance of Escherichia coli in vagina. CONCLUSION: The fertility factors associated with the reproductive endocrine and the genital tract environment affected vaginal microbiome in women of reproductive age. The species Escherichia coli, Streptococcus agalactiae, Prevotella intermedia, etc could be used as biomarkers to reflect the pathological state of reproductive endocrine and genital tract.

4.
Int J Neurosci ; 130(1): 52-63, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31512542

RESUMO

Purpose: Gait variability analysis has been clinically adopted to characterize the presentation of various neurological diseases. However, literature and practice lack a comprehensive murine model assessment of the gait deficits that result from transient focal ischemic stroke. Further, correlations between gait parameters and the gene expression profiles associated with brain ischemia have yet to be identified. This study quantitatively assesses gait deficits through a murine model of transient focal cerebral ischemia on day 7 to determine associations between gait deficits and ischemia-related gene expressions.Methods: A total of 182 dynamic and static gait parameters from the transient middle cerebral artery occlusion (MCAO) murine model for simulating human transient focal ischemic stroke on day 7 were measured using the CatWalk system. Pearson's correlation analysis and genes associated with ischemia were identified from the existing literature to aid the investigation of the relationship between gait variability and gene expression profiles.Results: Thirty-nine gait parameters and the mRNA expression levels of four of the eight ischemia-associated genes exhibited more significant change in the MCAO models (p < 0.005) on day 7. Twenty-six gait parameters exhibited strong correlations with four ischemia-associated genes.Conclusion: This examination of gait variability and the strong correlation to the gene expression profiles associated with transient focal brain ischemia on day 7 provides a quantitative and reliable assessment of the MCAO model's motor performance. This research provides valuable insights into the study of disease progression and offers novel therapeutic interventions in the murine modeling of ischemic stroke.

5.
iScience ; 21: 1-18, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31654850

RESUMO

Aberrant RAS signaling activation is common in cancers with even few Ras mutations, indicating alternative dysregulation other than genetic mutations. We identified a Ras GTPase-activating gene RASA5/SYNGAP1, at the common 6p21.3 deletion, methylated/downregulated in multiple carcinomas and different from other RASA family members (RASA1-RASA4), indicating its special functions in tumorigenesis. RASA5 mutations are rare, unlike other RASA members, whereas its promoter CpG methylation is frequent in multiple cancer cell lines and primary carcinomas and associated with patient's poor survival. RASA5 expression inhibited tumor cell migration/invasion and growth in mouse model, functioning as a tumor suppressor. RASA5 suppressed RAS signaling, depending on its Ras GTPase-activating protein catalytic activity, which could be counteracted by oncogenic HRas Q61L mutant. RASA5 knockdown enhanced Ras signaling to promote tumor cell growth. RASA5 also inhibited epithelial-mesenchymal transition (EMT) through regulating actin reorganization. Thus, epigenetic inactivation of RASA5 contributing to hyperactive RAS signaling is involved in Ras-driven human oncogenesis.

6.
Stem Cells Dev ; 28(20): 1365-1375, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31580778

RESUMO

Glaucoma is characterized by retinal ganglion cell (RGC) degeneration and is the second leading cause of blindness worldwide. However, current treatments such as eye drop or surgery have limitations and do not target the loss of RGC. Regenerative therapy using embryonic stem cells (ESCs) holds a promising option, but ethical concern hinders clinical applications on human subjects. In this study, we employed spermatogonial stem cells (SSCs) as an alternative source of ESCs for cell-based regenerative therapy in mouse glaucoma model. We generated functional RGCs from SSCs with a two-step protocol without applying viral transfection or chemical induction. SSCs were first dedifferentiated to embryonic stem-like cells (SSC-ESCs) that resemble ESCs in morphology, gene expression signatures, and stem cell properties. The SSC-ESCs then differentiated toward retinal lineages. We showed SSC-ESC-derived retinal cells expressed RGC-specific marker Brn3b and functioned as bona fide RGCs. To allow in vivo RGC tracing, Brn3b-EGFP reporter SSC-ESCs were generated and the derived RGCs were subsequently transplanted into the retina of glaucoma mouse models by intravitreal injection. We demonstrated that the transplanted RGCs could survive in host retina for at least 10 days after transplantation. SSC-ESC-derived RGCs can thus potentially be a novel alternative to replace the damaged RGCs in glaucomatous retina.

8.
Front Oncol ; 9: 486, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31245291

RESUMO

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression at a post-transcriptional level. We examined the role of miR-126 in granulosa cell tumor (GCT) of the ovaries. In tissues from malignant GCT patients miR-126 expression was repressed. We showed that miR-126 could inhibit proliferation, migration, hormone production and promote apoptosis of cancerous granulosa cells (GCs) in vitro. The role of miR-126 as "tumor suppressor" was confirmed by using a tumor formation model in vivo. By RNA-seq, immunohistochemical staining (IHC), Western blot and luciferase reporter assay, we identified and confirmed EGFL7 as a direct functional target of miR-126 in cancer GCs. Furthermore, we found that the AKT signaling pathway was associated with miR-126 and EGFL7 in cancer GCs. Taken together, our results demonstrate a function of miR-126 in the suppression of GCT development via the regulation of EGFL7.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31173666

RESUMO

BACKGROUND: Low muscularity (LM) is associated with high mortality in the Caucasian critically ill population. Muscularity can be accurately measured by the skeletal muscle index (SMI; cm2 /m2 ) generated by computed tomography (CT). This study aimed to establish the overall and sex-specific cutoff values that predict hospital mortality in an Asian critically ill population. METHODS: This single-center, retrospective, observational study included patients aged ≥18 years with an abdominal CT conducted within 72 hours of admission to the intensive care unit. SMI generated from CT images at the level of the mid-third lumbar vertebra were extracted from the medical records. Area under the receiver operating characteristic curves (AUC) was generated to determine the SMI cutoff values for hospital mortality. Association between LM (defined by SMI cutoff value) and hospital mortality was further evaluated by multivariable logistic regression. RESULTS: In a sample of 228 patients, the overall SMI cutoff value (cm2 /m2 ) for hospital mortality was 42.0 (AUC: 0.637; sensitivity: 66.7%, specificity: 56.8%), whereas it was 46.5 in males and 35.3 in females. More males than females had LM (51.4% vs 37.5%), and >40% of overweight/obese patients had LM. Patients with LM were older and had a longer duration of mechanical ventilation and hospitalization. After adjusting for known confounders, LM independently predicted hospital mortality in the overall sample (adjusted odds ratio: 2.42; 95% CI 1.16-5.03; P = 0.003) and in both sexes. CONCLUSION: This study established a set of SMI cutoff values that predict hospital mortality. LM is independently associated with hospital mortality.

10.
Int J Comput Assist Radiol Surg ; 14(10): 1815-1819, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31020576

RESUMO

PURPOSE: Lung nodules have very diverse shapes and sizes, which makes classifying them as benign/malignant a challenging problem. In this paper, we propose a novel method to predict the malignancy of nodules that have the capability to analyze the shape and size of a nodule using a global feature extractor, as well as the density and structure of the nodule using a local feature extractor. METHODS: We propose to use Residual Blocks with a 3 × 3 kernel size for local feature extraction and Non-Local Blocks to extract the global features. The Non-Local Block has the ability to extract global features without using a huge number of parameters. The key idea behind the Non-Local Block is to apply matrix multiplications between features on the same feature maps. RESULTS: We trained and validated the proposed method on the LIDC-IDRI dataset which contains 1018 computed tomography scans. We followed a rigorous procedure for experimental setup, namely tenfold cross-validation, and ignored the nodules that had been annotated by < 3 radiologists. The proposed method achieved state-of-the-art results with AUC = 95.62%, while significantly outperforming other baseline methods. CONCLUSIONS: Our proposed deep Local-Global network has the capability to accurately extract both local and global features. Our new method outperforms state-of-the-art architecture including Densenet and Resnet with transfer learning.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Humanos
11.
Stem Cells Dev ; 28(13): 833-845, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31020917

RESUMO

Doxycycline (DOX), an antibacterial drug, has been widely used in the inducible gene expression system. However, its effect was largely ignored when studying functions of the inducible transgene. By using a DOX-inducible Tet-ON system, we identified that DOX alone dramatically promoted dopaminergic (DA) neuron differentiation from human pluripotent stem cells (hPSCs), whereas the studied gene had no significant effects after considering the confounding factor DOX. These findings suggest that the effect of DOX should be taken into consideration when it is used in the inducible system especially during DA neuron differentiation from hPSCs. Meanwhile, it also suggests that DOX can be used as an efficient and inexpensive molecule to increase DA neuron differentiation efficacy from hPSCs for cell therapy.

12.
Artigo em Inglês | MEDLINE | ID: mdl-30949134

RESUMO

The granulosa cell (GC) is a critical somatic component of the ovary. It is essential for follicle development by supporting the developing oocyte, proliferating and producing sex steroids and disparate growth factors. Knowledge of the GC's function in normal ovarian development and function, and reproductive disorders, such as polycystic ovary syndrome (PCOS) and premature ovarian failure (POF), is largely acquired through clinical studies and preclinical animal models. Recently, microRNAs have been recognized to play important regulatory roles in GC pathophysiology. Here, we examine the recent findings on the role of miRNAs in the GC, including four related signaling pathways (Transforming growth factor-ß pathway, Follicle-stimulating hormones pathway, hormone-related miRNAs, Apoptosis-related pathways) and relevant diseases. Therefore, miRNAs appear to be important regulators of GC function in both physiological and pathological conditions. We suggest that targeting specific microRNAs is a potential therapeutic option for treating ovary-related diseases, such as PCOS, POF, and GCT.

13.
Development ; 146(6)2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-30824552

RESUMO

Neonatal germ cell development provides the foundation of spermatogenesis. However, a systematic understanding of this process is still limited. To resolve cellular and molecular heterogeneity in this process, we profiled single cell transcriptomes of undifferentiated germ cells from neonatal mouse testes and employed unbiased clustering and pseudotime ordering analysis to assign cells to distinct cell states in the developmental continuum. We defined the unique transcriptional programs underlying migratory capacity, resting cellular states and apoptosis regulation in transitional gonocytes. We also identified a subpopulation of primitive spermatogonia marked by CD87 (plasminogen activator, urokinase receptor), which exhibited a higher level of self-renewal gene expression and migration potential. We further revealed a differentiation-primed state within the undifferentiated compartment, in which elevated Oct4 expression correlates with lower expression of self-renewal pathway factors, higher Rarg expression, and enhanced retinoic acid responsiveness. Lastly, a knockdown experiment revealed the role of Oct4 in the regulation of gene expression related to the MAPK pathway and cell adhesion, which may contribute to stem cell differentiation. Our study thus provides novel insights into cellular and molecular regulation during early germ cell development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Análise de Sequência de RNA , Espermatogônias/citologia , Animais , Animais Recém-Nascidos , Apoptose , Adesão Celular , Diferenciação Celular , Perfilação da Expressão Gênica , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Microscopia de Fluorescência , Fator 3 de Transcrição de Octâmero/fisiologia , Receptores do Ácido Retinoico/fisiologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase/fisiologia , Espermatogênese/genética , Transcriptoma , Tretinoína/fisiologia
14.
J Mol Endocrinol ; 62(4): 197-206, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30913535

RESUMO

Obesity is a worldwide health problem with rising incidence and results in reproductive difficulties. Elevated saturated free fatty acids (FFAs) in obesity can cause insulin resistance (IR) in peripheral tissues. The high intra-follicular saturated FFAs may also account for IR in ovarian granulosa cells (GCs). In the present study, we investigated the relationship between saturated FFAs and IR in GCs by the use of palmitic acid (PA). We demonstrated that the glucose uptake in cultured GCs and lactate accumulation in the culture medium were stimulated by insulin, but the effects of insulin were attenuated by PA treatment. Besides, insulin-induced phosphorylation of Akt was reduced by PA in a dose- and time-dependent manner. Furthermore, PA increased phosphorylation of JNK and JNK blockage rescued the phosphorylation of Akt which was downregulated by PA. These findings highlighted the negative effect of PA on GCs metabolism and may partially account for the obesity-related reproductive disorders.

16.
Cell Death Differ ; 26(11): 2194-2207, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30760872

RESUMO

Lethal (3) malignant brain tumor like 2 (L3MBTL2) is a member of the MBT-domain proteins, which are involved in transcriptional repression and implicated in chromatin compaction. Our previous study has shown that L3MBTL2 is highly expressed in the testis, but its role in spermatogenesis remains unclear. In the present study, we found that L3MBTL2 was most highly expressed in pachytene spermatocytes within the testis. Germ cell-specific ablation of L3mbtl2 in the testis led to increased abnormal spermatozoa, progressive decrease of sperm counts and premature testicular failure in mice. RNA-sequencing analysis on L3mbtl2 deficient testes confirmed that L3MBTL2 was a transcriptional repressor but failed to reveal any significant changes in spermatogenesis-associated genes. Interestingly, L3mbtl2 deficiency resulted in increased γH2AX deposition in the leptotene spermatocytes, subsequent inappropriate retention of γH2AX on autosomes, and defective crossing-over and synapsis during the pachytene stage of meiosis I, and more germ cell apoptosis and degeneration in aging mice. L3MBTL2 interacted with the histone ubiquitin ligase RNF8. Inhibition of L3MBTL2 reduced nuclear RNF8 and ubH2A levels in GC2 cells. L3mbtl2 deficiency led to decreases in the levels of the RNF8 and ubH2A pathway and in histone acetylation in elongating spermatids, and in protamine 1 deposition and chromatin condensation in sperm. These results suggest that L3MBTL2 plays important roles in chromatin remodeling during meiosis and spermiogenesis.

17.
Biogerontology ; 20(3): 255-269, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30666569

RESUMO

Aging is a natural and unavoidable part of life. However, aging is also the primary driver of the dominant human diseases, such as cardiovascular disease, cancer, and neurodegenerative diseases, including Alzheimer's disease. Unraveling the sophisticated molecular mechanisms of the human aging process may provide novel strategies to extend 'healthy aging' and the cure of human aging-related diseases. Werner syndrome (WS), is a heritable human premature aging disease caused by mutations in the gene encoding the Werner (WRN) DNA helicase. As a classical premature aging disease, etiological exploration of WS can shed light on the mechanisms of normal human aging and facilitate the development of interventional strategies to improve healthspan. Here, we summarize the latest progress of the molecular understandings of WRN protein, highlight the advantages of using different WS model systems, including Caenorhabditis elegans, Drosophila melanogaster and induced pluripotent stem cell (iPSC) systems. Further studies on WS will propel drug development for WS patients, and possibly also for normal age-related diseases.


Assuntos
Envelhecimento/patologia , Síndrome de Werner/patologia , Animais , Caenorhabditis elegans/fisiologia , Drosophila melanogaster/fisiologia , Humanos , Modelos Biológicos , Mutação , Síndrome de Werner/genética , Síndrome de Werner/terapia
18.
Curr Protein Pept Sci ; 20(3): 265-276, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29895244

RESUMO

A variety of fungi, plants, and their different tissues are used in Traditional Chinese Medicine to improve health, and some of them are recommended for dietary therapy. Many of these plants and fungi contain antifungal proteins and peptides which suppress spore germination and hyphal growth in phytopathogenic fungi. The aim of this article is to review antifungal proteins produced by medicinal plants and fungi used in Chinese medicine which also possess anticancer and human immunodeficiency virus-1 (HIV-1) enzyme inhibitory activities.


Assuntos
Fármacos Anti-HIV/farmacologia , Antifúngicos , Antineoplásicos , Proteínas Fúngicas , Proteínas de Plantas , Plantas Medicinais/química , Animais , Fármacos Anti-HIV/química , Antifúngicos/química , Antifúngicos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Proteínas Fúngicas/química , Proteínas Fúngicas/farmacologia , Humanos , Medicina Tradicional Chinesa , Proteínas de Plantas/química , Proteínas de Plantas/farmacologia
19.
Curr Drug Targets ; 20(1): 16-28, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30156157

RESUMO

In previous studies, oxidative stress damage has been solely considered to be the mechanism of ovarian aging, and several antioxidants have been used to delay ovarian aging. But recently, more reports have found that endoplasmic reticulum stress, autophagy, sirtuins, mitochondrial dysfunction, telomeres, gene mutation, premature ovarian failure, and polycystic ovary syndrome are all closely related to ovarian aging, and these factors all interact with oxidative stress. These novel insights on ovarian aging are summarized in this review. Furthermore, as a pleiotropic molecule, melatonin is an important antioxidant and used as drugs for several diseases treatment. Melatonin regulates not only oxidative stress, but also the various molecules, and normal and pathological processes interact with ovarian functions and aging. Hence, the mechanism of ovarian aging and the extensive role of melatonin in the ovarian aging process are described herein. This systematic review supply new insights into ovarian aging and the use of melatonin to delay its onset, further supply a novel drug of melatonin for ovarian aging treatment.


Assuntos
Envelhecimento/efeitos dos fármacos , Melatonina/antagonistas & inibidores , Ovário/efeitos dos fármacos , Envelhecimento/metabolismo , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Melatonina/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ovário/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Sirtuínas/metabolismo
20.
J Clin Endocrinol Metab ; 104(4): 1049-1059, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30247605

RESUMO

CONTEXT: The high mobility group AT hook 2 (HMGA2) gene was previously identified in a genome-wide association study as a candidate risk gene that might be related to polycystic ovary syndrome (PCOS). Whether HMGA2 contributes to promoting granulosa cell (GC) proliferation in PCOS remains unknown. OBJECTIVE: We sought to determine whether HMGA2 is involved in the ovarian dysfunction of PCOS and in the mechanism of increased GC proliferation. PATIENTS AND CELLS: mRNA expression was analyzed in ovarian GCs from 96 women with PCOS and 58 healthy controls. Immortalized human GCs (KGN and SVOG cells) were used for the mechanism study. MAIN OUTCOME MEASURES: mRNA expression in ovarian GCs was measured using quantitative RT-PCR, and KGN cells were cultured for proliferation assays after overexpression or knockdown of target genes. Protein expression analysis, luciferase assays, and RNA binding protein immunoprecipitation assays were used to confirm the mechanism study. RESULTS: HMGA2 and IGF2 mRNA binding protein 2 (IMP2) were highly expressed in the GCs of women with PCOS, and the HMGA2/IMP2 pathway promoted GC proliferation. Cyclin D2 and SERPINE1 mRNA binding protein 1 were regulated by IMP2 and were highly expressed in women with PCOS. CONCLUSIONS: The HMGA2/IMP2 pathway was activated in women with PCOS and promoted the proliferation of GCs. This might provide new insights into the dysfunction of GCs in PCOS.


Assuntos
Células da Granulosa/patologia , Proteína HMGA2/metabolismo , Síndrome do Ovário Policístico/patologia , Proteínas de Ligação a RNA/metabolismo , Adulto , Animais , Linhagem Celular Tumoral , Proliferação de Células , China , Ciclina D2/metabolismo , Feminino , Perfilação da Expressão Gênica , Células HEK293 , Proteína HMGA2/genética , Humanos , Camundongos , Cultura Primária de Células , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Regulação para Cima
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