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Age at menarche (AAM) is a sign of puberty of females. It is a heritable trait associated with various adult diseases. However, the genetic mechanism that determines AAM and links it to disease risk is poorly understood. Aiming to uncover the genetic basis for AAM, we conducted a joint association study in up to 438,089 women from 3 genome-wide association studies of European and East Asian ancestries. A series of bioinformatical analyses and causal inference were then followed to explore in-depth annotations at the associated loci and infer the causal relationship between AAM and other complex traits/diseases. This largest meta-analysis identified a total of 21 novel AAM associated loci at the genome wide significance level (P < 5.0 × 10-8), 4 of which were European ancestry-specific loci. Functional annotations prioritized 33 candidate genes at newly identified loci. Significant genetic correlations were observed between AAM and 67 complex traits. Further causal inference demonstrated the effects of AAM on 13 traits, including forced vital capacity (FVC), high blood pressure, age at first live birth, etc, indicating that earlier AAM causes lower FVC, worse lung function, hypertension and earlier age at first (last) live birth. Enrichment analysis identified 5 enriched tissues, including the hypothalamus middle, hypothalamo hypophyseal system, neurosecretory systems, hypothalamus and retina. Our findings may provide useful insights that elucidate the mechanisms determining AAM and the genetic interplay between AAM and some traits of women.
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BACKGROUND AND AIMS: We aimed to assess the associations of baseline and long-term platelet count (PLT) with disability-free survival (DFS) among middle-aged and older Chinese. METHODS AND RESULTS: A total of 7296 participants were recruited in the analysis. Updated mean PLT was defined as the mean of the two PLT measurements (4 years between wave 1-3). The long-term status of PLT was defined as persistent low, attenuated, increased and persistent high PLT according to the optimal cut points from the receiver operating characteristic curves of the two PLT measurements, respectively. The primary outcome was DFS, evaluated by the first occurrence of either disability or mortality. During 6-year visit, 1579 participants experienced disability or all-cause mortality. The rates of primary outcome were significantly higher among participants with elevated baseline PLT and updated mean PLT. Multivariable adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of primary outcome were 1.253 (1.049-1.496) for highest baseline PLT tertile and 1.532 (1.124-2.088) for highest updated mean PLT tertile, comparing to the lowest tertiles. Multivariable-adjusted spline regression models showed a linear association of baseline PLT (plinearity < 0.001) and updated mean PLT (plinearity = 0.005) with primary outcome. Moreover, participants with persistent high PLT and increased PLT had increased risk of primary outcome (ORs [95% CIs]: 1.825 [1.282-2.597] and 1.767 [1.046-2.985], respectively), compared with the reference of those with persistent low PLT. CONCLUSION: This study proved elevated baseline PLT, especially long-term persist high or increased PLT was associated with less likelihood of DFS among middle-aged and older Chinese.
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População do Leste Asiático , Contagem de Plaquetas , Idoso , Humanos , Pessoa de Meia-Idade , China/epidemiologia , Estudos Longitudinais , Pessoas com DeficiênciaRESUMO
BACKGROUND AND AIMS: High sensitivity C-reactive protein (hsCRP) and triglyceride glucose (TyG) index were proved to be independent risk factors of cardiovascular disease (CVD). However, individual hsCRP or TyG index might not provide sufficient predictive value on CVD risk. The current study aimed to evaluate the cumulative effect of hsCRP and TyG index on CVD risk prospectively. METHODS AND RESULTS: A total of 9626 participants were enrolled in the analysis. The TyG index was calculated as ln(triglyceride [mg/dL] × fasting glucose [mg/dL]/2). The primary outcome was new-onset CVD events (cardiac events or stroke), and the secondary outcomes were new-onset cardiac events and stroke, separately. Participants were divided into 4 groups through the median of hsCRP and TyG index. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox proportion hazard models. From 2013 to 2018, 1730 participants experienced CVD (570 stroke and 1306 cardiac events). Linear associations were found between hsCRP, TyG index, hsCRP/TyG ratio and CVD (all p < 0.05). Compared to participants with low hsCRP/low TyG index, multivariable adjusted HRs (95% CIs) for those with high hsCRP/high TyG index were 1.17 (1.03-1.37) for CVD. No interaction of hsCRP and TyG index was found on CVD (p-interaction ≥0.05). Furthermore, adding hsCRP and TyG index simultaneously to conventional risk model improved risk reclassification for CVD, stroke and cardiac events (all p < 0.05). CONCLUSION: The present study suggested combination of hsCRP and TyG index might better improved the ability for risk stratification of CVD among middle-aged and older Chinese.
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Doenças Cardiovasculares , Acidente Vascular Cerebral , Pessoa de Meia-Idade , Humanos , Idoso , Glucose , Estudos Longitudinais , Proteína C-Reativa , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Glicemia/metabolismo , Aposentadoria , Triglicerídeos , População do Leste Asiático , Medição de Risco , Biomarcadores , Fatores de Risco , China/epidemiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologiaRESUMO
Recent studies have shown the relevance of gut microbiota in the occurrence and development of colorectal cancer (CRC), but the causal relationship remains unclear in the human population. The present study aims to assess the causal relationship from the gut microbiota to CRC and to identify specific causal microbe taxa via genome-wide association study (GWAS) summary statistics based two-sample Mendelian randomization (MR) analyses. Microbiome GWAS (MGWAS) in the TwinsUK 1,126 twin pairs was used as discovery exposure sample, and MGWAS in 1,812 northern German participants was used as replication exposure sample. GWAS of CRC in 387,156 participants from the UK Biobank (UKB) was used as the outcome sample. Bacteria were grouped into taxa features at both family and genus levels. In the discovery sample, a total of 30 bacteria features including 15 families and 15 genera were analyzed. Five features, including 2 families (Verrucomicrobiaceae and Enterobacteriaceae) and 3 genera (Akkermansia, Blautia, and Ruminococcus), were nominally significant. In the replication sample, the genus Blautia (discovery beta=-0.01, P = 0.04) was successfully replicated (replication beta=-0.18, P = 0.01) with consistent effect direction. Our findings identified genus Blautia that was causally associated with CRC, thus offering novel insights into the microbiota-mediated CRC development mechanism.
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Neoplasias Colorretais , Microbioma Gastrointestinal , Microbiota , Humanos , Microbioma Gastrointestinal/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Neoplasias Colorretais/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Bone mineral density (BMD) and lean body mass (LBM) not only have a considerable heritability each, but also are genetically correlated. However, common genetic determinants shared by both traits are largely unknown. In the present study, we performed a bivariate genome-wide association study (GWAS) meta-analysis of hip BMD and trunk lean mass (TLM) in 11,335 subjects from 6 samples, and performed replication in estimated heel BMD and TLM in 215,234 UK Biobank (UKB) participants. We identified 2 loci that nearly attained the genome-wide significance (GWS, p < 5.0 × 10-8) level in the discovery GWAS meta-analysis and that were successfully replicated in the UKB sample: 11p15.2 (lead SNP rs12800228, discovery p = 2.88 × 10-7, replication p = 1.95 × 10-4) and 18q21.32 (rs489693, discovery p = 1.67 × 10-7, replication p = 1.17 × 10-3). The above 2 pleiotropic loci may play a pleiotropic role for hip BMD and TLM development. So our findings provide useful insights that further enhance our understanding of genetic interplay between BMD and LBM.
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Composição Corporal/genética , Densidade Óssea/genética , Fêmur/química , Pleiotropia Genética , Estudo de Associação Genômica Ampla , Tronco/anatomia & histologia , Adulto , Idoso , Estudos de Coortes , Etnicidade/genética , Feminino , Heterogeneidade Genética , Técnicas de Genotipagem , Humanos , Masculino , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Estudos Observacionais como Assunto/estatística & dados numéricos , Osteoporose/genética , Polimorfismo de Nucleotídeo Único , Grupos Raciais/genéticaRESUMO
AIM/PURPOSE: Dental pulp stem cells (DPSCs) were widely used as seed cells in the field of tissue engineering and regenerative medicine, including spinal cord injury (SCI) repair and other neuronal degenerative diseases, due to their easy isolation, multiple differentiation potential, low immunogenicity and low rates of rejection during transplantation. Various studies have shown that bFGF can enhance peripheral nerve regeneration after injury, and phospho-ERK (p-ERK) activation as a major mediator may be involved in this process. Previous studies also have proved that a suitable biomaterial scaffold can carry and transport the therapeutic cells effectively to the recipient area. It has showed in our earlier experiments that 3D porous chitosan scaffolds exhibited a suitable circumstance for survival and neural differentiation of DPSCs in vitro. The purpose of the study was to evaluate the influence of chitosan scaffolds and bFGF on differentiation of DPSCs. MATERIALS AND METHODS: In current study, DPSCs were cultured in chitosan scaffolds and treated with neural differentiation medium for 7 days. The neural genes and protein markers were analyzed by western blot and immunofluorescence. Meanwhile, the relevant signaling pathway involved in this process was also tested. RESULTS: Our study revealed that the viability of DPSCs was not influenced by co-culture with the chitosan scaffolds as well as bFGF. Compared with the control and DPSC/chitosan-scaffold groups, the levels of GFAP, S100ß and ß-tubulin III significantly increased in the DPSC/chitosan-scaffold+bFGF group. CONCLUSION: Chitosan scaffolds were non-cytotoxic to the survival of DPSCs, and chitosan scaffolds combined with bFGF facilitated the neural differentiation of DPSCs. The transplantation of DPSCs/chitosan-scaffold+bFGF might be a secure and effective method of treating SCI and other neuronal diseases.
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Diferenciação Celular , Quitosana , Polpa Dentária , Fator 2 de Crescimento de Fibroblastos , Células-Tronco , Alicerces Teciduais , Adolescente , Adulto , Células Cultivadas , Humanos , Dente Serotino , Porosidade , Adulto JovemRESUMO
Aiming to uncover a shared genetic basis of abdominal obesity and osteoporosis, we performed a bivariate GWAS meta-analysis of femoral neck BMD (FNK-BMD) and trunk fat mass adjusted by trunk lean mass (TFMadj) in 11,496 subjects from 6 samples, followed by in silico replication in the large-scale UK Biobank (UKB) cohort. A series of functional investigations were conducted on the identified variants. Bivariate GWAS meta-analysis identified two novel pleiotropic loci 12q15 (lead SNP rs73134637, p = 3.45 × 10-7) and 10p14 (lead SNP rs2892347, p = 2.63 × 10-7) that were suggestively associated and that were replicated in the analyses of related traits in the UKB sample (osteoporosis p = 0.06 and 0.02, BMI p = 0.03 and 4.61 × 10-3, N up to 499,520). Cis-eQTL analysis demonstrated that allele C at rs73134637 was positively associated with IFNG expression in whole blood (N = 369, p = 0.04), and allele A at rs11254759 (10p14, p = 9.49 × 10-7) was negatively associated with PRKCQ expression in visceral adipose tissue (N = 313, p = 0.04) and in lymphocytes (N = 117, p = 0.03). As a proof-of-principle experiment, the function of rs11254759, which is 235 kb 5'-upstream from PRKCQ gene, was investigated by the dual-luciferase reporter assay, which clearly showed that the haplotype carrying rs11254759 regulated PRKCQ expression by upregulating PRKCQ promoter activity (p = 4.60 × 10-7) in an allelic specific manner. Mouse model analysis showed that heterozygous PRKCQ deficient mice presented decreased fat mass compared to wild-type control mice (p = 3.30 × 10-3). Mendelian randomization analysis demonstrated that both FNK-BMD and TFMadj were causally associated with fracture risk (p = 1.26 × 10-23 and 1.18 × 10-11). Our findings may provide useful insights into the genetic association between osteoporosis and abdominal obesity.
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Pleiotropia Genética/genética , Interferon gama/genética , Obesidade Abdominal/genética , Osteoporose/genética , Proteína Quinase C-theta/genética , Locos de Características Quantitativas/genética , Animais , Índice de Massa Corporal , Estudos de Coortes , Feminino , Colo do Fêmur/fisiologia , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Análise da Randomização Mendeliana , Camundongos , Camundongos Knockout , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genéticaRESUMO
BACKGROUND: Fat mass and lean mass are two biggest components of body mass. Both fat mass and lean mass are under strong genetic determinants and are correlated. METHODS: We performed a bivariate genome-wide association meta-analysis of (lean adjusted) leg fat mass and (fat adjusted) leg lean mass in 12,517 subjects from 6 samples, and followed by in silico replication in large-scale UK biobank cohort sample (N = 370 097). RESULTS: We identified four loci that were significant at the genome-wide significance (GWS, α = 5.0 × 10-8) level at the discovery meta-analysis, and successfully replicated in the replication sample: 2q36.3 (rs1024137, pdiscovery = 3.32 × 10-8, preplication = 4.07 × 10-13), 5q13.1 (rs4976033, pdiscovery = 1.93 × 10-9, preplication = 6.35 × 10-7), 12q24.31 (rs4765528, pdiscovery = 7.19 × 10-12, preplication = 1.88 × 10-11) and 18q21.32 (rs371326986, pdiscovery = 9.04 × 10-9, preplication = 2.35 × 10-95). The above four pleiotropic loci may play a pleiotropic role for fat mass and lean mass development. CONCLUSIONS: Our findings further enhance the understanding of the genetic association between fat mass and lean mass and provide a new theoretical basis for their understanding.
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Adiposidade/genética , Pleiotropia Genética , Estudo de Associação Genômica Ampla , Adulto , Idoso , Genótipo , Humanos , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , Reino UnidoRESUMO
The mechanism of local inflammation and systemic injury in chronic periodontitis is complicated, in which and exosomes play an important role. In our study, we found that T helper cell 17 (Th17)/regulatory T cell (Treg) balance is destabilized in the peripheral blood of patients with periodontitis, with upregulated Th17 or downregulated Treg, respectively. Porphyromonas gingivalis lipopolysaccharide (LPS) was used to simulate the inflammatory microenvironment of chronic periodontitis. The exosomes were extracted from periodontal ligament stem cells (PDLSCs) in LPS-induced periodontitis environment, which inversely effected on CD4+ T cells under normal and inflammatory conditions. Furthermore, compared with exosomes from normal PDLSCs, lower expression of microRNA-155-5p (miR-155-5p) and higher expression of Sirtuin-1 (SIRT1) were observed in exosomes from LPS-stimulated PDLSCs. Exosomes from PDLSCs alleviated inflammatory microenvironment through Th17/Treg/miR-155-5p/SIRT1 regulatory network. This study aimed to find the "switching" factors that affected the further deterioration of periodontitis to maximally control the multiple downstream damage signal factors to further understand periodontitis and find new targets for its treatment.
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MicroRNAs/metabolismo , Ligamento Periodontal/citologia , Periodontite/metabolismo , Sirtuína 1/metabolismo , Células-Tronco/metabolismo , Doença Crônica , Regulação da Expressão Gênica/imunologia , Gengiva/metabolismo , Gengiva/patologia , Humanos , MicroRNAs/genética , Periodontite/imunologia , Sirtuína 1/genética , Linfócitos T Reguladores , Células Th17RESUMO
AIM: Casein kinase 2 interacting protein-1 (CKIP-1) is a recently discovered intracellular regulator of bone formation, muscle cell differentiation, and tumor cell proliferation. Our study aims to identify the inhibition of BMP2-Smad1/5 signaling by CKIP-1 in odontoblastic differentiation of human dental pulp stem cells (DPSCs). MATERIALS AND METHODS: DPSCs infected CKIP-1 siRNA or transfected CKIP-1 full-length plasmid were cultured in odontoblastic differentiation medium or added noggin (200 ng/mL) for 21 days. We examined the effects of CKIP-1 on odontoblastic differentiation, mineralized nodules formation, and interaction by western blot, real-time polymerase chain reaction (RT-PCR), alkaline phosphatase (ALP) staining, alizarin red S staining, and immunoprecipitation. RESULTS: Firstly, we have demonstrated that CKIP-1 expression markedly decreased time-dependently along with cell odontoblastic differentiation. Indeed, the silence of CKIP-1 upregulated odontoblastic differentiation via BMP2-Smad1/5 signaling, while CKIP-1 over-expression had a negative effect on odontoblastic differentiation of DPSCs. Furthermore, CKIP-1 could interact with Neuropilin-1 (NRP1). CONCLUSIONS: This work provides data that advocates a novel perception on odontoblastic differentiation of DPSCs. Therefore, inhibiting the expression of CKIP-1 may be of great significance to the development of dental caries.
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Proteína Morfogenética Óssea 2/metabolismo , Diferenciação Celular , Polpa Dentária/citologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neuropilina-1/metabolismo , Odontoblastos/citologia , Transdução de Sinais , Células-Tronco/citologia , Adolescente , Proteínas de Transporte/metabolismo , Regulação para Baixo/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Modelos Biológicos , Fenótipo , Ligação Proteica , Proteínas Smad/metabolismo , Células-Tronco/metabolismo , Regulação para Cima/genética , Adulto JovemRESUMO
OBJECTIVE: To evaluate the prevalence and severity of periodontal disease in Chinese rheumatoid arthritis patients. SUBJECTS AND METHODS: This cross-sectional study included 128 RA and 109 healthy controls. Two dentists conducted periodontal status including Plaque index (PI), Gingival index (GI), pocket probing depths (PPDs), Clinical attachment level (CAL) and Bleeding on probing (BOP) independently. Sociodemographic, lifestyle, clinical parameters and use of medication were assessed. Data were analyzed by Student's t test, χ2 test, Wilcoxin-Mann- Whitney's test, Correlational Analysis, univariate or multivariate logistic regression. RESULTS: The periodontal status was significantly worse in RA, especially the condition of dental and gingival status. RA had 4.68-fold. After adjusted potential risk factors, RA had 10.26-fold. The independent variable related to GI was DAS28 (p = .05) negatively, to the contrary, ESR (p = .013) was positively associated; the independent variable positively and related to periodontitis was educational level (p = .021) and anti-CCP positivity (p = .002). Through multivariate logistic regression, age and swollen joint were the independent variable related to periodontitis of RA (OR 1.087, p = .044) and (OR 1.560, p = .008) respectively. CONCLUSIONS: Chinese RA patients show higher odds of PD. It is important to take early interventions in combination with medical therapy.
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Artrite Reumatoide/complicações , Doenças Periodontais/complicações , Doenças Periodontais/epidemiologia , Adulto , Idoso , Artrite Reumatoide/etnologia , Povo Asiático , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Índice de Placa Dentária , Humanos , Pessoa de Meia-Idade , Perda da Inserção Periodontal , Doenças Periodontais/etnologia , Índice PeriodontalRESUMO
Dental pulp stem cells (DPSCs) were the most widely used seed cells in the field of neural regeneration and bone tissue engineering, due to their easily isolation, lack of ethical controversy, low immunogenicity and low rates of transplantation rejection. The purpose of this study was to investigate the role of basic fibroblast growth factor (bFGF) and nerve growth factor (NGF) on neural differentiation of DPSCs in vitro. DPSCs were cultured in neural differentiation medium containing NGF and bFGF alone or combination for 7 days. Then neural genes and protein markers were analyzed using western blot and RT-PCR. Our study revealed that bFGF and NGF increased neural differentiation of DPSCs synergistically, compared with bFGF and NGF alone. The levels of Nestin, MAP-2, ßIII-tubulin and GFAP were the most highest in the DPSCs + bFGF + NGF group. Our results suggested that bFGF and NGF signifiantly up-regulated the levels of Sirt1. After treatment with Sirt1 inhibitor, western blot, RT-PCR and immunofluorescence staining showed that neural genes and protein markers had markedly decreased. Additionally, the ERK and AKT signaling pathway played a key role in the neural differentiation of DPSCs stimulated with bFGF + NGF. These results suggested that manipulation of the ERK and AKT signaling pathway may be associated with the differentiation of bFGF and NGF treated DPSCs. Our date provided theoretical basis for DPSCs to treat neurological diseases and repair neuronal damage.
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Diferenciação Celular/efeitos dos fármacos , Polpa Dentária/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fator de Crescimento Neural/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Adolescente , Diferenciação Celular/fisiologia , Células Cultivadas , Polpa Dentária/citologia , Polpa Dentária/fisiologia , Humanos , Regeneração Nervosa/fisiologia , Células-Tronco/fisiologia , Adulto JovemRESUMO
Previous studies have revealed that bone marrow-mesenchymal stem cells (BM-MSCs) from systemic lupus erythematosus (SLE) patients exhibited early signs of senescence, which may participate in the development of SLE. However, the molecular mechanisms about this phenomenon have not been fully elucidated. In the current study, we aimed to investigate whether Janus kinase (JAK)-signaling transducers and activators of transcription (STAT) signaling mediated the senescence of BM-MSCs from SLE patients. Twelve female SLE patients and healthy subjects were enrolled in the study. All BM-MSCs were isolated by density gradient centrifugation. Western blot analysis was used to test the expression of JAK-STAT signaling molecules. We observed the activity of ß-gal of cells, the changes of cytoskeletal structure by F-actin staining, and the distribution of cell cycle by flow cytometry. BM-MSCs from SLE patients showed prominent features of senescence, and abnormal activation of JAK-STAT signaling transduction, high level of phosphorylated JAK2, and STAT3. After stimulation of IFN-γ in normal MSCs, JAK-STAT signaling was activated. The cell volume and the number of senescence-associated ß-galactosidase (SA-ß-gal) positive in SLE BM-MSCs were increased. The organization of cytoskeleton was nearly disordered. The rate of cell proliferation was decreased. AG490, the inhibitor of JAK2, and knockdown of STAT3 in BM-MSCs, could significantly reverse the senescence. In summary, our study indicated that JAK-STAT signaling pathway may play a critical role in the senescence of SLE BM-MSCs.
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Medula Óssea/patologia , Senescência Celular , Janus Quinase 2/metabolismo , Lúpus Eritematoso Sistêmico/patologia , Células-Tronco Mesenquimais/patologia , Transdução de Sinais , Adolescente , Adulto , Medula Óssea/metabolismo , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Fosforilação , Fator de Transcrição STAT3/metabolismo , Adulto JovemRESUMO
Distraction osteogenesis (DO) remains a major challenge in orthopedic and craniofacial surgery. The transplantion of mesenchymal stem cells (MSCs) could reduce the treatment period and the associated complications by increasing new bone formation during long-bone DO. Runt-related transcription factor 2 (Runx2) encodes a nuclear protein that is a pivotal regulator of osteoblast differentiation. It significantly stimulates calcium accumulation and alkaline phosphatase (ALP) activity in dental pulp stem cells (DPSCs). In this study, we investigated the effects of gene therapy using Runx2 on new bone formation during tibia DO of rabbits. The distraction gap of the rabbits was injected with adenovirus (Adv)-Runx2-green fluorescent protein (GFP)-transfected DPSCs (overexpression group, Group OE) or Adv-GFP-transfected DPSCs (negative control group, Group NC). Rabbits in the control group (Groups CON) were injected with physiologic saline. The generation of new bone tissue in the distraction gap was studied by radiographic examination, micro-computed tomography (CT) evaluation, histological analyze, and Mechanical testing at weeks 8 in the consolidation period. Excellent bone formation in the distracted callus was observed in Group OE and Group NC. Moreover, the OE group showed better bone formation and the highest bone mineral density (BMD) and bone mineral content (BMC). Group CON animals showed inadequate bone formation in the distracted callus compared to the other groups. The results suggest that gene therapy using Runx2-modiï¬ed DPSCs was more effective during bone deposition and new bone formation in tibia DO.
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Diferenciação Celular/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Terapia Genética , Osteogênese por Distração , Osteogênese/genética , Animais , Polpa Dentária/citologia , Polpa Dentária/transplante , Proteínas de Fluorescência Verde/genética , Humanos , Mandíbula/crescimento & desenvolvimento , Mandíbula/cirurgia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Coelhos , Tíbia/crescimento & desenvolvimento , Tíbia/cirurgia , Microtomografia por Raio-XRESUMO
Cell-based transplantation strategies hold great potential for spinal cord injury (SCI) repair. Chitosan scaffolds have therapeutic benefits for spinal cord regeneration. Human dental pulp stem cells (DPSCs) are abundant available stem cells with low immunological incompatibility and can be considered for cell replacement therapy. The purpose of this study is to investigate the role of chitosan scaffolds in the neural differentiation of DPSCs in vitro and to assess the supportive effects of chitosan scaffolds in an animal model of SCI. DPSCs were incubated with chitosan scaffolds. Cell viability and the secretion of neurotrophic factors were analyzed. DPSCs incubated with chitosan scaffolds were treated with neural differentiation medium for 14 days and then neural genes and protein markers were analyzed by Western blot and reverse transcription plus the polymerase chain reaction. Our study revealed a higher cell viability and neural differentiation in the DPSC/chitosan-scaffold group. Compared with the control group, the levels of BDNF, GDNF, b-NGF, and NT-3 were significantly increased in the DPSC/chitosan-scaffold group. The Wnt/ß-catenin signaling pathway played a key role in the neural differentiation of DPSCs combined with chitosan scaffolds. Transplantation of DPSCs together with chitosan scaffolds into an SCI rat model resulted in the marked recovery of hind limb locomotor functions. Thus, chitosan scaffolds were non-cytotoxic and provided a conducive and favorable microenvironment for the survival and neural differentiation of DPSCs. Transplantation of DPSCs might therefore be a suitable candidate for treating SCI and other neuronal degenerative diseases.
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Diferenciação Celular/efeitos dos fármacos , Quitosana/farmacologia , Polpa Dentária/citologia , Neurônios/citologia , Traumatismos da Medula Espinal/patologia , Transplante de Células-Tronco , Células-Tronco/citologia , Alicerces Teciduais/química , Adolescente , Animais , Caspase 3/metabolismo , Células Cultivadas , Técnicas de Silenciamento de Genes , Humanos , Masculino , Atividade Motora/efeitos dos fármacos , Fatores de Crescimento Neural/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Células-Tronco/ultraestrutura , Via de Sinalização Wnt/efeitos dos fármacos , Adulto Jovem , beta Catenina/metabolismoRESUMO
Dental pulp stem cells (DPSCs) are multipotent adult stem cells capable of differentiating along the osteoblast, adipocyte, and chondrocyte lineages. Regulating differentiation of DPSCs may be a useful tool for regenerative medicine and cell-based therapy in oral diseases. Multisignaling pathways are involved in osteogenic differentiation of DPSCs. Recent studies show that cAMP/PKA/CREB signaling could stimulate the expression of genes such as bone morphogenic proteins 2 (BMP2), inhibitor of DNA binding 2 (ID2), bone sialoprotein, osteocalcin, and type XXIV collagen, which have been implicated in osteogenesis and bone formation. Activator of G-protein signaling 3 (AGS3, gene name G-protein signaling modulator-1, Gpsm1), an accessory protein for G-protein signaling, plays an important role in regulating the phosphorylation of cyclic AMP response element-binding protein (p-CREB). However, the involvement of AGS3 in osteogenic differentiation of DPSCs has not been explored. Our data indicated that increased expression of AGS3 would inhibit osteogenic differentiation of DPSCs exposed to inflammatory cytokine tumor necrosis factor α (TNF-α) via cAMP/PKA/CREB signaling. The negative role of AGS3 in osteogenic differentiation was further confirmed by knocking down and over expression of AGS3. Our findings may provide clinical implications for osteoporosis.
Assuntos
Polpa Dentária/citologia , Inibidores de Dissociação do Nucleotídeo Guanina/fisiologia , Células-Tronco Multipotentes/citologia , Osteogênese/fisiologia , Fator de Necrose Tumoral alfa , Adulto , Idoso , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Regulação da Expressão Gênica , Humanos , Proteína 2 Inibidora de Diferenciação/genética , Proteína 2 Inibidora de Diferenciação/metabolismo , Sialoproteína de Ligação à Integrina/genética , Sialoproteína de Ligação à Integrina/metabolismo , Masculino , Pessoa de Meia-Idade , Osteocalcina/genética , Osteocalcina/metabolismo , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaAssuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Obesidade/genética , Osteoporose/genética , Feminino , Loci Gênicos/genética , Humanos , Masculino , Obesidade/complicações , Obesidade/patologia , Osteoporose/complicações , Osteoporose/patologia , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
Human dental pulp contains a rapidly proliferative subpopulation of precursor cells termed dental pulp stem cells (DPSCs) that show self-renewal and multilineage differentiation, including neurogenic, chondrogenic, osteogenic and adipogenic. We previously reported that tomuor necrosis factor-α (TNF-α) (10 ng/mL) triggered osteogenic differentiation of human DPSCs via the nuclear factor-κB (NF-κB) signaling pathway. While previous studies showed that cells treated with TNF-α at higher concentrations showed decreased osteogenic differentiation capability. In this study we analyze the function of TNF-α (100 ng/mL) on osteogenic differentiation of human DPSCs for the first time and identify the underlying molecule mechanisms. Our data revealed that TNF-α with higher concentration significantly reduced mineralization and the expression of bone morphogenetic protein 2 (BMP2), alkaline phosphatase (ALP) and runt-related transcription factor 2 (RUNX2). Further, we revealed that TNF-α could suppress the osteogenic differentiation of DPSCs via increasing the expression of RAC1, which could activate the Wnt/ß-catenin signaling pathway and liberate ß-catenin to translocate into the nucleus. Genetic silencing of RAC1 expression using siRNA restored osteogenic differentiation of DPSCs. Our findings may provide a potential approach to bone regeneration in inflammatory microenvironments.
Assuntos
Diferenciação Celular , Polpa Dentária/citologia , Osteogênese , Células-Tronco/citologia , Fator de Necrose Tumoral alfa/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Adolescente , Adulto , Células Cultivadas , Polpa Dentária/patologia , Humanos , Células-Tronco/patologia , Adulto JovemRESUMO
Dental pulp stem cells (DPSCs) are a type of mesenchymal stem cell (MSC) characterized by multi-lineage differentiation making it an attractive choice for tissue regeneration. However, before DPSCs can be used for cell-based therapy, we have to understand their biological properties in response to intrinsic and extrinsic stimuli such as lipopolysaccharide (LPS). DPSCs were therefore stimulated with LPS and senescence was evaluated by senescence-associated ß-galactosidase (SA-ß-gal) staining, with cell number and cell-cycle arrest being examined by BrdU assay and flow cytometry, respectively. The morphology of DPSCs was characterized by their flat shape, increased size and increased SA-ß-gal activity after repeated stimulation (3 or 6 times) with LPS. Reactive oxygen species (ROS) staining showed that the number of ROS-stained cells and the DCFH fluorescent level were higher in the LPS-treated DPSCs compared with those in the untreated DPSCs. Protein and mRNA expression levels of γ-H2A.X and p16(INK4A) were also increased in DPSCs with repeated LPS stimulation. We found that the LPS bound with Toll-like receptor 4 (TLR4) and that TLR4 signaling accounted for p16(INK4A) expression. Further results indicated that the senescence of DPSCs stimulated repeatedly with LPS was reversed by p16(INK4A) short interfering RNA. The DNA damage response and p16(INK4A) pathways might be the main mediators of DPSC senescence induced by repeated LPS stimulation. Thus, DPSCs tend to undergo senescence after repeated activation, implying that DPSC senescence starts after many inflammatory challenges. Ultimately, these findings should lead to a better understanding of DPSC-based clinical therapy.
Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Polpa Dentária/citologia , Células-Tronco Mesenquimais/citologia , Dente Serotino/citologia , Receptor 4 Toll-Like/metabolismo , Adolescente , Adulto , Apoptose , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Senescência Celular , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , Inibidor p16 de Quinase Dependente de Ciclina/genética , Reparo do DNA , Histonas/biossíntese , Humanos , Lipopolissacarídeos , Ligação Proteica , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo , Adulto Jovem , beta-GalactosidaseRESUMO
Insulin-like growth factor 1 (IGF-1) is a multifunctional peptide that can enhance osteogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs). However, it remains unclear whether IGF-1 can promote osteogenic differentiation of human dental pulp stem cells (DPSCs). In our study, DPSCs were isolated from the impacted third molars, and treated with IGF-1. Osteogenic differentiation abilities were investigated. We found that IGF-1 activated the mTOR signaling pathway during osteogenic differentiation of DPSCs. IGF-1 also increased the expression of runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), osterix (OSX) and collagen type I (COL I) during this process. Rapamycin, an mTOR inhibitor, blocked osteogenic differentiation induced by IGF-1. Meanwhile, CCK-8 assay and flow cytometry results demonstrated that 10-200 ng/mL IGF-1 could enhance proliferation ability of DPSCs and 100 ng/mL was the optimal concentration. In summary, IGF-1 could promote proliferation and osteogenic differentiation of DPSCs via mTOR pathways, which might have clinical implications for osteoporosis.