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1.
BMC Neurol ; 20(1): 77, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32126981

RESUMO

BACKGROUND: This study aimed to investigate the roles of CYP3A4 and CYP11A1 variants in ischemic stroke (IS) susceptibility among the Han Chinese population. METHODS: Four hundred seventy-seven patients with IS and 493 healthy controls were enrolled. Seven single-nucleotide polymorphisms (SNPs) of CYP3A4 and CYP11A1 were genotyped by Agena MassARRAY. Odds ratio (OR) and 95% confidence intervals (CI) were calculated by logistic regression adjusted for age and gender. RESULTS: We found that CYP3A4 rs3735451 (OR = 0.81, p = 0.039) and rs4646440 (OR = 0.72, p = 0.021) polymorphisms decreased the risk of IS. CYP3A4 rs4646440 (OR = 0.74, p = 0.038) and CYP11A1 rs12912592 (OR = 1.58, p = 0.034) polymorphisms were correlated with IS risk in males. CYP3A4 rs3735451 (OR = 0.63, p = 0.031) and rs4646440 (OR = 0.57, p = 0.012) possibly weaken the IS susceptibility at age > 61 years. Besides, CYP3A4 rs4646437 (OR = 0.59, p = 0.029), CYP11A1 rs12912592 (OR = 1.84, p = 0.017) and rs28681535 (OR = 0.66, p = 0.038) were associated with IS risk at age ≤ 61 years. CYP11A1 rs28681535 TT genotype was higher high-density lipoprotein cholesterol level than the GT and GG genotype (p = 0.027). CONCLUSIONS: Our findings indicated that rs3735451, rs4646440, rs4646437 in CYP3A4 and rs28681535 in CYP11A1 might be protective factors for IS, while CYP11A1 rs12912592 polymorphism be a risk factor for IS in Chinese Han population.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32171529

RESUMO

Affective disorders are a set of mental disorders and particularly disrupt the mental health of susceptible women during puberty, pregnancy, parturition and menopause transition, which are characterized by dramatic changes in reproductive hormone profiles. The serum FSH level changes significantly during these periods; yet, the role of FSH in mood regulation is poorly understood. In the current study, FSHR knockout (Fshr-/-) mice displayed enhanced affective disorder behaviors in an open field test and a forced swim test, accompanied by altered gene expression profiles. The differentially expressed genes between Fshr-/- mice and Fshr+/+ mice were enriched in multiple neuroendocrine metabolic pathways. FSHR deletion significantly increased/decreased the mRNA and/or protein expression levels of AOX1, RDH12, HTR3a and HTR4 in mood-mediating brain regions, including the hippocampus and prefrontal cortex. These results reveal that FSH signaling is involved in the development of affective disorders.

4.
Crit Rev Biotechnol ; : 1-17, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32212873

RESUMO

With the high tolerance for acetic acid and abundant multifunctional enzymes, acetic acid bacteria (AAB), as valuable biocatalysts, exhibit great advantages during industrial acetic acid production and value-added chemical fermentation. However, low biomass and a low production rates arising from acid stress remains major hurdles in industrial processes. Engineering AAB with excellent properties is expected to obtain economically viable production and facilitates their biotechnological applications. Here, the investigation of acetic acid-tolerance mechanisms and metabolic features is discussed, and effective targets are provided for the metabolic engineering of AAB. Next, we review the advances in improving AAB and compare these advances with improvement to other model acid-tolerant microorganisms. Furthermore, future directions involving the combination of systems biology and synthetic biology to achieve efficient biomanufacturing in AAB are highlighted.

5.
Endocrine ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32215813

RESUMO

PURPOSE: The role of thyroid autoimmunity in the association between obesity and hyperthyrotropinaemia remains unclear. We aimed to assess the relationship between obesity, autoimmunity, and hyperthyrotropinaemia. METHODS: In this population-based cross-sectional study, 12531 Chinese individuals (18-80 years) with thyroid function test were categorized into three groups by body mass index (BMI) and were categorized into three layers by thyroid autoantibodies. Multivariate logistic regression was employed to assess the correlation and interaction effect. RESULTS: There was no significant difference in prevalence of hyperthyrotropinaemia (P = 0.637) among three BMI groups. After stratification, the difference of serum thyrotropin (P < 0.01) and prevalence of hyperthyrotropinaemia (P < 0.01) between the three groups have significant linear trends at the positive levels of thyroid peroxidase antibody (TPOAb) or/and thyroglobulin antibody (TgAb). When TPOAb and TgAb were positive, the risk of hyperthyrotropinaemia increased 1.857-fold in overweight group and 2.201-fold in obese group compared with normal group. Compared with negative TPOAb and TgAb, the risk of hyperthyrotropinaemia for individuals with two positive antibodies increased 3.310-fold, 4.969-fold, and 5.122-fold in the three BMI groups. The adjusted OR (95% CI) for interaction were 1.033 (0.752-1.419) for overweight and one positive antibodies, 1.935 (1.252-2.990) for overweight and two positive antibodies, 1.435 (0.978-2.105) for obesity and one positive antibodies and 2.191 (1.252-3.832) for obesity and two positive antibodies. CONCLUSION: Overweight and obesity were associated with hyperthyrotropinaemia only in presence of thyroid autoimmunity, and obesity might aggravate the pathogenic effect of autoimmunity on hyperthyrotropinaemia. There was an interaction effect between obesity and autoimmunity on the prevalence of hyperthyrotropinaemia.

6.
Acta Pharmacol Sin ; 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32203083

RESUMO

Alteration in reproductive hormones profile is associated with the increasing risk of menopausal depression in women. Serum follicle-stimulating hormone (FSH) level is changed during the menopause transition, while the effect of FSH on menopausal depression has remained undefined. In this study we investigated whether or how FSH affected menopausal depression in postmenopausal (ovariectomized) FSHR knockout mice (Fshr-/-). We found that Fshr-/- mice displayed aggravated depression-like behaviors, accompanied by severe oxidative stress in the whole brain, resulted from significantly reduced glutamate cysteine ligase modifier subunit (GCLm) in glutathione synthesis and glucose-6-phosphate dehydrogenase (G6PD) in NADP/NADPH transition. Importantly, administration of ROS scavenger N-acetyl cysteine (NAC, 150 mg · kg-1 · d-1, i.p. for 12 weeks) attenuated the depression-like behaviors of Fshr-/- mice. Consistent with these in vivo experiment results, we found that pretreatment with FSH (50, 100 ng/mL) dose-dependently increased protein levels of GCLm and G6PD, and decreased the ROS production in N2a mouse neuroblastoma cells. These findings demonstrate that FSH signaling is involved in pathogenesis of menopausal depression, and likely to maintain the redox-optimized ROS balance in neurons.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32208550

RESUMO

The enoyl-acyl carrier protein reductase enzyme FabI is essential for fatty acid biosynthesis in Staphylococcus aureus and represents a promising target for the development of novel, urgently needed anti-staphylococcal agents. Here, we elucidate the mode of action of the kalimantacin antibiotics, a novel class of FabI inhibitors with clinically-relevant activity against multidrug-resistant S. aureus . By combining X-ray crystallography with molecular dynamics simulations, in vitro kinetic studies and chemical derivatization experiments, we characterize the interaction between the antibiotics and their target, and we demonstrate that the kalimantacins bind in a unique conformation that differs significantly from the binding mode of other known FabI inhibitors. We also investigate mechanisms of acquired resistance in S. aureus and identify key residues in FabI that stabilize the binding of the antibiotics. Our findings provide intriguing insights into the mode of action of a novel class of FabI inhibitors that will inspire future anti-staphylococcal drug development.

8.
Sci Rep ; 10(1): 1604, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005880

RESUMO

Aphids are important agricultural pests causing major yield losses worldwide. Since aphids can rapidly develop resistance to chemical insecticides there is an urgent need to find alternative aphid pest management strategies. Despite the economic importance of bluegreen aphid (Acyrthosiphon kondoi), very few genetic resources are available to expand our current understanding and help find viable control solutions. An artificial diet is a desirable non-invasive tool to enable the functional characterisation of genes in bluegreen aphid and discover candidate target genes for future use in RNA interference (RNAi) mediated crop protection against aphids. To date no artificial diet has been developed for bluegreen aphid, so we set out to develop a suitable diet by testing and optimising existing diets. Here, we describe an artificial diet for rearing bluegreen aphid and also provide a proof of concept for the supplementation of the diet with RNAi molecules targeting the salivary gland transcript C002 and gap gene hunchback, resulting in bluegreen aphid mortality which has not yet been documented in this species. Managing this pest, for example via RNAi delivery through artificial feeding will be a major improvement to test bluegreen aphid candidate target genes for future pest control and gain significant insights into bluegreen aphid gene function.

9.
Hypertension ; 75(3): 772-780, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32008433

RESUMO

The recommendations for the diagnosis of stage 1 hypertension were recently revised by the American Heart Association primarily based on its impact on cardiovascular disease risks. Whether the newly diagnosed stage 1 hypertension impacts pregnancy complications remain poorly defined. We designed a retrospective cohort study to investigate the associations of stage 1 hypertension detected in early gestation (<20 weeks) with risks of adverse pregnancy outcomes stratified by prepregnancy body mass index. A total of 47 874 women with singleton live births and blood pressure (BP) <140/90 mm Hg were included, with 5781 identified as stage 1a (systolic BP, 130-134 mm Hg; diastolic BP, 80-84 mm Hg; or both) and 3267 as stage 1b hypertension (systolic BP, 135-139 mm Hg; diastolic BP, 85-90 mm Hg; or both). Slightly higher, yet significant, rates and risks of gestational diabetes mellitus, preterm delivery, and low birth weight (<2500 g) were observed in both groups compared with normotensive controls. Importantly, women with stage 1a and stage 1b hypertension had significantly increased incidences of hypertensive disorders in pregnancy compared with normotensive women (adjusted odds ratio, 2.34 [95% CI, 2.16-2.53]; 3.05 [2.78-3.34], respectively). After stratifying by body mass index, stage 1a and 1b hypertension were associated with increased hypertensive disorders in pregnancy risks in both normal weight (body mass index, 18.5-24.9; adjusted odds ratio, 2.44 [2.23-2.67]; 3.26 [2.93-3.63]) and the overweight/obese (body mass index, ≥25; adjusted odds ratio, 1.90 [1.56-2.31]; 2.36 [1.92-2.90]). Current findings suggested significantly increased adverse pregnancy outcomes associated with stage 1 hypertension based on the revised American Heart Association guidelines, especially in women with prepregnancy normal weight.

10.
Comput Methods Programs Biomed ; 190: 105340, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-32023506

RESUMO

BACKGROUND AND OBJECTIVES: Fluorescein angiography (FA) is widely used in ophthalmology for examining retinal hemodynamics and vascular morphology. Artery-venous classification is an important step in FA image processing for measurement of feature parameters, such as arterio-venous passage time (AVP) and arterio-venous width ratio (AVR) that are proven useful in clinical assessment of circulation disturbance and vessel abnormalities. However, manual artery-venous classification needs expertise and is rather time consuming, and little effort has been devoted to develop automatic classification methods. In order to solve this problem, we propose a novel artery-venous classification method using region growing strategy with sequential and structural features (RGSS). METHODS: The main procedures of our proposed RGSS method include: (i) registration of FA image sequence by mutual-information method; (ii) extraction of sequential features of the dye perfusion process from the registrated FA images; (iii) extraction of vessel structural features from vascular centerline map; (iv) based on the obtained features, seeds of arteries and veins within initial growing region (here optic disk) are generated and then propagated in the entire vessel network using region growing strategy. The RGSS method was tested on our own dataset and public Duke dataset, and its performance was evaluated quantitatively. RESULTS: Tests show that RGSS method is able to classify arteries and veins from the complicated vessel network in FA images, with high classification accuracy of 0.91 ± 0.04 on Duke dataset and 0.92 ± 0.03 on our dataset. The employed sequential and structural features are demonstrated to be effective in classifying thin arteries and veins at vessel crossings. CONCLUSIONS: Automatic artery-venous classification can be accomplished using our proposed RGSS method with high accuracy. The RGSS method not only emancipates ophthalmologists from hard work of manual marking of arteries and veins, but also helps in measuring important parameters (such as AVP and AVR) for clinical assessment of circulation disturbance and vessel abnormalities.

11.
Mol Ther Nucleic Acids ; 19: 1134-1144, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32059339

RESUMO

Circular RNAs (circRNAs) are a class of noncoding RNAs that are broadly expressed in various biological cells and function in regulating gene expression. However, the molecular mechanisms that link circRNAs with progression of papillary thyroid carcinoma (PTC) are not well understood. In the present study, the function of circ_0006156 (circFNDC3B) was investigated in human PTC cells. First, we detected the expression of circFNDC3B in PTC tissues and PTC cell lines by RT-PCR. A luciferase reporter assay and AGO2-RNA immunoprecipitation (RIP) was used to confirm the relationship between circFNDC3B and microRNA (miR)-1178. PTC cells were stably transfected with small interfering RNA (siRNA) against circFNDC3B, and cell proliferation, migration, and invasion were detected to evaluate the effect of circFNDC3B in PTC, while tumorigenesis was assayed in nude mice. In this study, circFNDC3B was observed to be upregulated in PTC tissues and cell lines. Knockdown of circFNDC3B inhibited cell proliferation and promoted cell apoptosis in PTC cells. Bioinformatics analysis predicted that there is a circFNDC3B/miR-1178/Toll-like receptor 4 (TLR4) axis in PTC. The dual-luciferase reporter system validated the direct interaction of circFNDC3B, miR-1178, and TLR4. Furthermore, circFNDC3B facilitates PTC progression in vivo. Importantly, we demonstrated that circFNDC3B was upregulated in serum exosomes from PTC patients. In summary, our study demonstrated that circFNDC3B modulates PTC progression through the miR-1178/TLR4 pathway. Our findings indicated that circFNDC3B may serve as a promising therapeutic target for the treatment of PTC patients.

12.
Mol Ther Nucleic Acids ; 19: 1153-1163, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32059341

RESUMO

Circular RNAs (circRNAs) are a class of non-coding RNAs broadly expressed in cells of various species. However, the molecular mechanisms that link circRNAs with progression of papillary thyroid carcinoma (PTC) are not well understood. In the present study, we attempted to provide novel basis for targeted therapy for PTC from the aspect of circRNA-miRNA-mRNA interaction. We investigated the expression of circRNAs in five paired PTC tissues and normal tissues by microarray analysis. The circRNA microarray assay followed by qRT-PCR was used to verify the differential expression of hsa_circ_0059354, which is located on chromosome 20 and derived from RASSF2, and thus we named it circRASSF2. The qRT-PCR analysis was to investigate the expression pattern of circRASSF2 in PTC tissues and cell lines. Then the effects of circRASSF2 on cell proliferation and apoptosis were assessed in PTC in vitro. Furthermore, bioinformatics online programs predicted and luciferase reporter assays were used to validate the association of circRASSF2 and miR-1178 in PTC cells. In this study, circRASSF2 was observed to be upregulated in PTC tissues and cell lines. Knockdown of circRASSF2 inhibited cell proliferation and promoted cell apoptosis in PTC cells. Bioinformatics analysis predicted that there is a circRASSF2/miR-1178/TLR4 axis in PTC. A dual-luciferase reporter system validated the direct interaction of circRASSF2, miR-1178, and TLR4. Furthermore, circRASSF2 facilitates PTC progression in vivo. Importantly, we demonstrated that circRASSF2 was upregulated in serum exosomes from PTC patients. In summary, our study demonstrates that circRASSF2 modulates PTC progression through the miR-1178/TLR4 pathway. Our findings indicate that circRASSF2 may serve as a promising therapeutic target for the treatment of PTC patients.

13.
Biochem Biophys Res Commun ; 524(4): 791-797, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32019676

RESUMO

Increased granulosa cell (GC) proliferation may contribute to abnormal folliculogenesis in patients with polycystic ovary syndrome (PCOS), which affects approximately 10% reproductive aged women. However, the mechanisms underlying increased GC proliferation in PCOS remain incompletely understood. In this study, we identified miR-3940-5p as a hub miRNA in GC from PCOS using weighted gene co-expression network analysis (WGCNA), and real-time polymerase chain reaction (RT-PCR) analysis confirmed that miR-3940-5p was significantly increased in GC from PCOS. Enrichment analysis of predicted target genes of miR-3940-5p indicated potential roles of miR-3940-5p in follicular development and cell proliferation regulation. Consistently, functional study confirmed that miR-3940-5p overexpression promoted granulosa cell proliferation. Integrated analysis of mRNA expression profiling data and predicted target genes of miR-3940-5p identified potassium voltage-gated channel subfamily A member 5 (KCNA5) as a potential target of miR-3940-5p, and was validated by luciferase reporter assay. Finally, functional analysis suggested that miR-3940-5p promoted GC proliferation in a KCNA5 dependent manner. In conclusion, miR-3940-5p was a hub miRNA upregulated in GC from PCOS, and promoted GC proliferation by targeting KCNA5.

15.
Lipids Health Dis ; 19(1): 8, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937307

RESUMO

BACKGROUND: It is believed that deposition of amyloid beta (Aß) in the brain is the central pathological changes of Alzheimer's disease (AD), which triggers a series of pathological processes. However, the relationship between dyslipidemia and AD is uncertain. Considering the peripheral Aß levels are related to brain Aß deposition, we explore the relationships between blood lipids and plasma Aß. METHODS: Participants who lived in the selected village of Xi'an for more than 3 years were enrolled, aged 40-85 years (n = 1282, 37.9% male). Fasting blood lipid, plasma Aß levels, basic information and living habits were measured. Multiple linear regressions were used. RESULTS: In total population, blood lipids were not associated with plasma Aß. After stratified by blood pressure, serum total cholesterol (TC) and low-density lipoprotein (LDL-c) were positively associated with plasma Aß42 levels (ßTC = 0.666, PTC = 0.024; ßLDL-c = 0.743, PLDL-c = 0.011, respectively) in normal blood pressure. LDL-c was negatively associated with plasma Aß40 levels (ß = - 0.986, P = 0.037) in high blood pressure. CONCLUSION: Elevated plasma Aß42 levels are associated with higher TC and LDL-c in normal blood pressure. Elevated plasma Aß40 levels are associated with lower LDL-c in high blood pressure. This indicated that the relationships between blood lipids and plasma Aß were confounded by blood pressure.

16.
Invest Ophthalmol Vis Sci ; 61(1): 1, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31995153

RESUMO

Purpose: Vacuolar protein sorting 35 (Vps35) mutations and protein dysfunction have been linked to the hyperphosphorylation and accumulation of tau protein in a number of central neurodegenerative disorders. The aims of the present study were to investigate the mechanism underlying the tau hyperphosphorylation caused by Vps35 deficiency. Methods: The cells used in this study were primary retinal ganglion cells (RGCs). The rat retinal glutamate excitotoxicity model was used in vivo. Fresh retinal tissues or eyeballs were collected at different time points. The expression and interactions of Vps35, Cdk5/p35, tau hyperphosphorylation, LAMP1, EEA1 and UBE1 in RGCs were studied by immunofluorescence staining, Western blotting, and immunoprecipitation. Results: The downregulation and overexpression of Vps35 increased and decreased the expression of p35 and tau hyperphosphorylation, respectively. More important, roscovitine, a Cdk5 inhibitor, could effectively decrease the hyperphosphorylated tau level induced by Vps35 deficiency. Furthermore, this study confirmed that the inhibition of Vps35 could increase the activity of Cdk5/p35 by affecting the lysosomal degradation of p35 and lead to the degeneration of RGCs. Conclusions: These findings demonstrate the possibility that Cdk5/p35 acts as a "cargo" of Vps35 and provide new insights into the pathogenesis of RGC degeneration caused by hyperphosphorylated tau protein. Vps35 is a potential target for basic research and clinical treatment of RGC degeneration in many ocular diseases such as glaucoma.


Assuntos
Quinase 5 Dependente de Ciclina/metabolismo , Fosfotransferases/metabolismo , Células Ganglionares da Retina/metabolismo , Proteínas de Transporte Vesicular/deficiência , Proteínas tau/metabolismo , Animais , Western Blotting , Células Cultivadas , Quinase 5 Dependente de Ciclina/antagonistas & inibidores , Regulação para Baixo , Técnica Indireta de Fluorescência para Anticorpo , Ácido Glutâmico/toxicidade , Glicoproteínas de Membrana Associadas ao Lisossomo/metabolismo , Masculino , Camundongos , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Degeneração Retiniana/induzido quimicamente , Degeneração Retiniana/metabolismo , Roscovitina/farmacologia , Transfecção , Enzimas Ativadoras de Ubiquitina/metabolismo , Proteínas de Transporte Vesicular/metabolismo
17.
J Biophotonics ; : e201960218, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31990430

RESUMO

In preclinical researches, bioluminescence tomography (BLT) has widely been used for tumor imaging and monitoring, imaged-guided tumor therapy, and so forth. For these biological applications, both tumor spatial location and morphology analysis are the leading problems needed to be taken into account. However, most existing BLT reconstruction methods were proposed for some specific applications with a focus on sparse representation or morphology recovery, respectively. How to design a versatile algorithm that can simultaneously deal with both aspects remains an impending problem. In this study, a Sparse-Graph Manifold Learning (SGML) method was proposed to balance the source sparseness and morphology, by integrating non-convex sparsity constraint and dynamic Laplacian graph model. Furthermore, based on the nonconvex optimization theory and some iterative approximation, we proposed a novel iteratively reweighted soft thresholding algorithm (IRSTA) to solve the SGML model. Numerical simulations and in vivo experiments result demonstrated that the proposed SGML method performed much superior to the comparative methods in spatial localization and tumor morphology recovery for various source settings. It is believed that the SGML method can be applied to the related optical tomography and facilitate the development of optical molecular tomography.

18.
Oxid Med Cell Longev ; 2020: 1249630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31998431

RESUMO

Background & Aims: Oxidative stress-related liver diseases were shown to be associated with elevated serum thyroid stimulating hormone (TSH) levels. Mitochondria are the main source of cellular reactive oxygen species. However, the relationship between TSH and hepatic mitochondrial stress/dysfunction and the underlying mechanisms are largely unknown. Here, we focused on exploring the effects and mechanism of TSH on hepatic mitochondrial stress. Methods: As the function of TSH is mediated through the TSH receptor (TSHR), Tshr -/- mice and liver-specific Tshr -/- mice and liver-specific Tshr -/- mice and liver-specific. Results: A relatively lower degree of mitochondrial stress was observed in the livers of Tshr -/- mice and liver-specific in vitro. Microarray and RT-PCR analyses showed that Tshr -/- mice and liver-specific. Conclusions: TSH stimulates hepatic CypD acetylation through the lncRNA-AK044604/SIRT1/SIRT3 signaling pathway, indicating an essential role for TSH in mitochondrial stress in the liver.

19.
EBioMedicine ; 52: 102618, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31982829

RESUMO

BACKGROUND: The retinal pigment epithelium (RPE) has the potential to regenerate the entire neuroretina upon retinal injury in amphibians. In contrast, this regenerative capacity has been lost in mammals. The reprogramming of differentiated somatic cells into induced pluripotent stem cells (iPSCs) by viral transduction of exogenous stem cell factors has triggered a revolution in regenerative medicine. However, the risks of potential mutation(s) caused by random viral vector insertion in host genomes and tumor formation in recipients hamper its clinical application. One alternative is to immortalize adult stem cells with limited potential or to partially reprogram differentiated somatic cells into progenitor-like cells through non-integration protocols. METHODS: Sphere-induced RPE stem cells (iRPESCs) were generated from adult mouse RPE cells. Their stem cell functionality was studied in a mouse model of retinal degeneration. The molecular mechanism underlying the sphere-induced reprogramming was investigated using microarray and loss-of-function approaches. FINDINGS: We provide evidence that our sphere-induced reprogramming protocol can immortalize and transform mouse RPE cells into iRPESCs with dual potential to differentiate into cells that express either RPE or photoreceptor markers both in vitro and in vivo. When subretinally transplanted into mice with retinal degeneration, iRPESCs can integrate to the RPE and neuroretina, thereby delaying retinal degeneration in the model animals. Our molecular analyses indicate that the Hippo signaling pathway is important in iRPESC reprogramming. INTERPRETATION: The Hippo factor Yap1 is activated in the nuclei of cells at the borders of spheres. The factors Zeb1 and P300 downstream of the Hippo pathway are shown to bind to the promoters of the stemness genes Oct4, Klf4 and Sox2, thereby likely transactivate them to reprogram RPE cells into iRPESCs. FUND: National Natural Science Foundation of China and the National Institute of Health USA.

20.
Cell Cycle ; 19(4): 448-463, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31944163

RESUMO

Long non-coding RNAs (lncRNAs) have been proposed to correlate with various carcinomas, yet the role of lncRNA SNHG7 in nasopharyngeal carcinoma (NPC) is hardly studied. This study intends to examine the molecular mechanism of SNHG7 on NPC cells. The NPC tissues and nasopharyngeal tissues of mild inflammation of nasopharyngeal mucosa were obtained. SNHG7, miR-140-5p, and GLI3 mRNA and protein expression in tissues and in the CNE1, HONE1, C666-1, CNE2, and normal NP69 cell lines was detected. IC50 and the protein expression of related drug-resistant genes of CNE2 and CNE2/DDP cells were determined. Proliferative ability, cell colony formation rate, cell cycle, and apoptosis of CNE2 and CNE2/DDP cells were also detected. SNHG7, miR-140-5p, and GLI3 mRNA and protein expression in CNE2 and CNE2/DDP cells in each group was detected. SNHG7's cell localization, the binding sites of SNHG7 and miR-140-5p along with miR-140-5p and GLI3 were detected. Overexpressed SNHG7 and GLI3, and underexpressed miR-140-5p were found in NPC tissues and cells. SNHG7 silencing and miR-140-5p elevation declined the drug resistance of drug-resistant NPC cells and their parent cells, restrained NPC cell colony formation ability and proliferation, and boosted cell apoptosis. SNHG7 specially bound to miR-140-5p, and SNHG7 silencing elevated miR-140-5p expression. GLI3 was a direct target gene of miR-140-5p and miR-140-5p elevation diminished GLI3 expression. MiR-140-5p inhibition reversed the impacts of SNHG7 silencing on NPC cells. In summary, our study reveals that downregulated SNHG7 restricts GLI3 expression by upregulating miR-140-5p, which further suppresses cell proliferation, and promotes apoptosis of NPC.

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