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1.
Cell Mol Life Sci ; 81(1): 67, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38289345

RESUMO

Skeletal muscle is a highly specialized tissue composed of myofibres that performs crucial functions in movement and metabolism. In response to external stimuli and injuries, a range of stem/progenitor cells, with muscle stem cells or satellite cells (MuSCs) being the predominant cell type, are rapidly activated to repair and regenerate skeletal muscle within weeks. Under normal conditions, MuSCs remain in a quiescent state, but become proliferative and differentiate into new myofibres in response to injury. In addition to MuSCs, some interstitial progenitor cells (IPCs) such as fibro-adipogenic progenitors (FAPs), pericytes, interstitial stem cells expressing PW1 and negative for Pax7 (PICs), muscle side population cells (SPCs), CD133-positive cells and Twist2-positive cells have been identified as playing direct or indirect roles in regenerating muscle tissue. Here, we highlight the heterogeneity, molecular markers, and functional properties of these interstitial progenitor cells, and explore the role of muscle stem/progenitor cells in skeletal muscle homeostasis, aging, and muscle-related diseases. This review provides critical insights for future stem cell therapies aimed at treating muscle-related diseases.


Assuntos
Músculo Esquelético , Células-Tronco , Homeostase , Adipogenia
2.
Nano Lett ; 24(26): 8208-8215, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38913825

RESUMO

In the heterostructure of two-dimensional (2D) materials, many novel physics phenomena are strongly dependent on the Moiré superlattice. How to achieve the continuous manipulation of the Moiré superlattice in the same sample is very important to study the evolution of various physical properties. Here, in minimally twisted monolayer-multilayer graphene, we found that bubble-induced strain has a huge impact on the Moiré superlattice. By employing the AFM tip to dynamically and continuously move the nanobubble, we realized the modulation of the Moiré superlattice, like the evolution of regular triangular domains into long strip domain structures with single or double domain walls. We also achieved controllable modulation of the Moiré superlattice by moving multiple nanobubbles and establishing the coupling of nanobubbles. Our work presents a flexible method for continuous and controllable manipulation of Moiré superlattices, which will be widely used to study novel physical properties in 2D heterostructures.

3.
Int J Mol Sci ; 25(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39125656

RESUMO

Abnormal shifts in global climate, leading to extreme weather, significantly threaten the safety of individuals involved in outdoor activities. Hypothermia-induced coma or death frequently occurs in clinical and forensic settings. Despite this, the precise mechanism of central nervous system injury due to hypothermia remains unclear, hindering the development of targeted clinical treatments and specific forensic diagnostic indicators. The GEO database was searched to identify datasets related to hypothermia. Post-bioinformatics analyses, DEGs, and ferroptosis-related DEGs (FerrDEGs) were intersected. GSEA was then conducted to elucidate the functions of the Ferr-related genes. Animal experiments conducted in this study demonstrated that hypothermia, compared to the control treatment, can induce significant alterations in iron death-related genes such as PPARG, SCD, ADIPOQ, SAT1, EGR1, and HMOX1 in cerebral cortex nerve cells. These changes lead to iron ion accumulation, lipid peroxidation, and marked expression of iron death-related proteins. The application of the iron death inhibitor Ferrostatin-1 (Fer-1) effectively modulates the expression of these genes, reduces lipid peroxidation, and improves the expression of iron death-related proteins. Severe hypothermia disrupts the metabolism of cerebral cortex nerve cells, causing significant alterations in ferroptosis-related genes. These genetic changes promote ferroptosis through multiple pathways.


Assuntos
Córtex Cerebral , Ferroptose , Hipotermia , Neurônios , Ferroptose/genética , Animais , Hipotermia/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Neurônios/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos , Masculino , Ratos , Fenilenodiaminas/farmacologia , Cicloexilaminas
4.
Clin Proteomics ; 20(1): 2, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609216

RESUMO

BACKGROUND: Spermatozoa have the task of delivering an intact paternal genome to the oocyte and supporting successful embryo development. The detection of sperm DNA fragmentation (SDF) has been emerging as a complementary test to conventional semen analysis for male infertility evaluation, but the mechanism leading to SDF and its impact on assisted reproduction remain unclear. Therefore, the study identified and analyzed the differentially expressed proteins of sperm with high and low SDF. METHODS: Semen samples from men attended the infertility clinic during June 2020 and August 2020 were analyzed, and sperm DNA fragmentation index (DFI) was detected by the sperm chromatin structure assay. Semen samples with low DFI (< 30%, control group) and high DFI (≥ 30%, experimental group) were optimized by density gradient centrifugation (DGC), and the differentially expressed proteins of obtained sperm were identified by the Sequential Window Acquisition of All Theoretical Mass Spectra Mass Spectrometry (SWATH-MS) and performed GO and KEGG analysis. RESULTS: A total of 2186 proteins were identified and 1591 proteins were quantified, of which 252 proteins were identified as differentially expressed proteins, including 124 upregulated and 128 downregulated. These differentially expressed proteins were involved in metabolic pathways, replication/recombination/repair, acrosomal vesicles, kinase regulators, fertilization, tyrosine metabolism, etc. Western blotting results showed that the expression levels of RAD23B and DFFA proteins and the levels of posttranslational ubiquitination and acetylation modifications in the experimental group were significantly higher than those in the control group, which was consistent with the results of proteomics analysis. CONCLUSIONS: Proteomic markers of sperm with high DNA fragmentation can be identified by the SWATH-MS and bioinformatic analysis, and new protein markers and posttranslational modifications related to sperm DNA damage are expected to be intensively explored. Our findings may improve our understanding of the basic molecular mechanism of sperm DNA damage.

5.
Reprod Biomed Online ; 46(1): 11-19, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36272896

RESUMO

RESEARCH QUESTION: What are the molecular mechanisms leading to human sperm DNA damage? DESIGN: Semen samples were collected and the sperm DNA fragmentation index (DFI) was assessed. Differentially expressed RNA in spermatozoa with a high (DFI ≥30%, experimental group) or normal (DFI <30%, control group) DFI were identified by RNA-sequencing (RNA-seq) technology, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was performed. Three differentially expressed RNA related to sperm DNA damage and repair, namely PMS1, TP53BP1 and TLK2, were validated using real-time quantitative (RT-qPCR). RESULTS: A total of 19,970 expressed RNA were detected in the two groups. Compared with the control group, the expression levels of 189 RNA in the experimental group were significantly increased and those of 163 genes decreased. Gene Ontology enrichment analysis showed that these RNA were mainly concentrated in the ATPase-dependent transmembrane transport complex, extracellular exosome, somatic cell DNA recombination, protein binding, cytoplasm and regulation of localization. KEGG pathway analysis showed that these RNA were mainly related to the PI3K-Akt signalling pathway, endocytosis, p53 signalling pathway and cGMP-PKG signalling pathway. The RT-qPCR results showed that the expression levels of PMS1, TP53BP1 and TLK2 in the experimental group were significantly lower than in the control group (P = 0.01, 0.015 and 0.004, respectively), which was identical to the results of RNA sequencing. CONCLUSIONS: Differentially expressed RNA related to sperm DNA damage and repair may be identified by RNA-seq technology, which provides new insights into the understanding of sperm DNA damage and repair, and will help to discover new biomarkers related to sperm DNA damage.


Assuntos
Fosfatidilinositol 3-Quinases , Sêmen , Humanos , Masculino , RNA-Seq , Fosfatidilinositol 3-Quinases/metabolismo , Espermatozoides/metabolismo , Dano ao DNA , Perfilação da Expressão Gênica , Análise de Sequência de RNA , RNA/genética , Fragmentação do DNA
6.
Nutr Metab Cardiovasc Dis ; 33(3): 500-506, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36646600

RESUMO

BACKGROUND AND AIMS: To investigate the relationship between elevated serum uric acid (SUA) levels and blood pressure (BP). METHODS AND RESULTS: Based on the Beijing Health Management Cohort, 5276 health examination people were enrolled. Cross-lagged model was used to explore the relationship between SUA levels and blood pressure. The results showed: (1) increased SUA and increased systolic blood pressure (SBP): ① The path coefficients from baseline SUA to follow-up SBP were statistically significant in both the general population (ß = 0.034, P < 0.05) and men (ß = 0.048, P < 0.05). The path coefficients from baseline SBP to follow-up SUA were not statistically significant in either the general population (ß = 0.010, P > 0.05) or men (ß = 0.011, P > 0.05). ② The path coefficients from baseline SUA to follow-up SBP and from baseline SBP to follow-up SUA were not statistically significant in women with BMI ≥ 25 kg/m2 and BMI < 25 kg/m2. (2) Increased SUA and diastolic blood pressure (DBP): ① There was no statistical significance between the path coefficients from baseline DBP to follow-up SUA and the path coefficients from baseline SUA to follow-up DBP. ② In men and women, BMI ≥ 25 kg/m2 and BMI < 25 kg/m2, the path coefficients from baseline DBP to follow-up SUA and from baseline SUA to follow-up DBP were not statistically significant. CONCLUSIONS: SUA can increase blood pressure in the general male population; no reverse time sequence relationship was found. The temporal relationships between SUA levels and SBP abnormalities were different in the sex and BMI subgroups. No bidirectional causal temporal relationship was found between SUA elevation and DBP abnormality.


Assuntos
Hipertensão , Humanos , Masculino , Feminino , Pressão Sanguínea/fisiologia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/etiologia , Ácido Úrico , Estudos de Coortes , Fatores de Risco
7.
Gynecol Endocrinol ; 39(1): 2217260, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37236239

RESUMO

OBJECTIVE: We retrospectively analyzed the correlation between different endometrial preparation protocols and pregnancy outcomes in patients with polycystic ovary syndrome (PCOS) who underwent frozen embryo transfer (FET). METHODS: A total of 200 PCOS patients who underwent FET were divided into HRT group (n = 65), LE group (n = 65), GnRHa + HRT group (n = 70) according to different endometrial preparation protocols. The endometrial thickness on the day of endometrial transformation, the number of embryos transferred, and the number of high-quality embryos transferred were compared among the three groups. The pregnancy outcomes of FET in the three groups were compared and analyzed, and a further multivariate logistic regression model was used to analyze the factors influencing FET pregnancy outcomes in PCOS patients. RESULTS: Endometrial thickness on the day of endometrial transformation, clinical pregnancy rate and live birth rate in GnRHa + HRT group were higher than those in the HRT group and LE group. The results of multivariate regression analysis showed that the pregnancy outcome of PCOS patients undergoing FET was significantly associated with the patient's age, endometrial preparation protocols, number of embryos transferred, endometrial thickness, and duration of infertility. CONCLUSION: Compared with HRT or LE alone, GnRHa + HRT protocol results in higher levels of endometrial thickness on the day of endometrial transformation, clinical pregnancy rate, and live birth rate. Female age, endometrial preparation protocols, number of embryos transferred, endometrial thickness, and duration of infertility are determined as factors influencing pregnancy outcomes in PCOS patients undergoing FET.


Assuntos
Criopreservação , Transferência Embrionária , Infertilidade , Síndrome do Ovário Policístico , Feminino , Humanos , Gravidez , Criopreservação/métodos , Transferência Embrionária/métodos , Infertilidade/complicações , Síndrome do Ovário Policístico/complicações , Resultado da Gravidez/epidemiologia , Taxa de Gravidez , Estudos Retrospectivos
8.
Environ Geochem Health ; 45(6): 3789-3804, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36580188

RESUMO

Chlorinated paraffins (CPs) are ubiquitous anthropogenic contaminants that have been found in various environmental media. The objective of this study was to determine concentrations, spatial distribution, possible sources and potential health risk of SCCPs and MCCPs in urban road dust collected from Shanghai, China. The concentrations ranged from 9.74 to 11,400 ng g-1 for ΣSCCPs, 44.1 to 49,900 ng g-1 for ΣMCCPs and 53.9 to 61,400 ng g-1 for total CPs, respectively. MCCPs were the dominant component in all road dust, averagely accounting for 82.8% of total CPs. The concentrations of CPs in dust collected from traffic and commercial areas were significantly higher than those from campus, industrial, park and residential areas (p < 0.01), which could be attributed to tire wear in heavy traffic. All dust samples were divided into two groups by hierarchical cluster analysis for both SCCPs and MCCPs, and the most abundant homologue groups in most samples were C10Cl7-10 and C13Cl7-9 for SCCPs, and C14Cl7-9 and C15Cl8-9 for MCCPs. Correlation analysis showed that all carbon homologues in road dusts were highly correlated each other, suggesting SCCPs and MCCPs in dust maybe came from similar sources. Three sources for CPs in dust samples were apportioned by the PMF model; their relative contributions to the total CPs burden in dust were 25.6% for factor 1 (commercial CP mixture), 13.7% for factor 2 (long-distance transport) and 60.7% for factor 3 (commercial CP mixture). The median estimated daily intakes of total CPs via road dust were 1.78 × 10-5 for children and 3.0 × 10-6 mg kg-1 day-1 for adults, respectively. Quantitative risk assessment using non-cancer hazard index and total margin of exposure of total CPs indicated that total CPs at the present level in road dust pose no significant risk for both children and adults in Shanghai.


Assuntos
Poeira , Hidrocarbonetos Clorados , Adulto , Criança , Humanos , China , Poeira/análise , Parafina/análise , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise
9.
Zhongguo Zhong Yao Za Zhi ; 48(17): 4738-4746, 2023 Sep.
Artigo em Zh | MEDLINE | ID: mdl-37802813

RESUMO

This study aimed to explore the mechanism of albiflorin in the treatment of Alzheimer's disease(AD) based on network pharmacology, molecular docking, and in vitro experiments. Network pharmacology was used to predict the potential targets and pathways of albiflorin against AD, and molecular docking technology was used to verify the binding affinity of albiflorin to key target proteins. Finally, the AD cell model was induced by Aß_(25-35) in rat pheochromocytoma(PC12) cells and intervened by albiflorin to validate core targets and pathways. The results of network pharmacological analysis showed that albiflorin acted on key targets such as mitogen-activated protein kinase-1(MAPK1 or ERK2), albumin(ALB), epidermal growth factor receptor(EGFR), caspase-3(CASP3), and sodium-dependent serotonin transporter(SLC6A4), and signaling pathways such as MAPK, cAMP, and cGMP-PKG. The results of molecular docking showed that albiflorin had strong binding affinity to MAPK1(ERK2). In vitro experiments showed that compared with the blank group, the model group showed decreased cell viability, decreased expression level of B-cell lymphoma 2(Bcl-2), increased Bcl-2-associated X protein(Bax), and reduced phosphorylation level of extracellular signal-regulated kinase 1/2(ERK1/2) and the relative expression ratio of p-ERK1/2 to ERK1/2. Compared with the model group, the albiflorin group showed potentiated cell viability, up-regulated expression of Bcl-2, down-regulated Bax, and increased phosphorylation level of ERK1/2 and the relative expression ratio of p-ERK1/2 to ERK1/2. These results suggest that the mechanism of albiflorin against AD may be related to its activation of the MAPK/ERK signaling pathway and its inhibition of neuronal apoptosis.


Assuntos
Doença de Alzheimer , Animais , Ratos , Doença de Alzheimer/tratamento farmacológico , Proteína X Associada a bcl-2 , Farmacologia em Rede , Simulação de Acoplamento Molecular
10.
Int J Mol Sci ; 24(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36613978

RESUMO

Osteoarthritis (OA) is a chronic joint disease characterized by the degeneration of articular cartilage and thickening and sclerosis of the subchondral bone. Mechanical factors play significant roles in the development and progression of OA, but it is still controversial whether exercise or rest is a more effective treatment for OA patients. In this study, we compared the effects of swimming and immobilization at different stages of OA in mice. Four weeks (the middle stage of OA) or eight weeks (the late stage of OA) after DMM (destabilization of the medial meniscus) surgery, the mice were subjected to four-week immobilization or swimming. Ink blot analysis and a beam walking test were performed to measure the gait and balance ability. Histological analysis was performed to determine the trabecular bone area, the thickness of subchondral bone, the thickness of the cartilage, the OARSI score, and the expression of MMP13 (matrix metalloproteinases) and IL-6 (interleukin). The results showed that at the middle stage of OA, both immobilization and swimming slowed down the progression of OA. Immobilization relieved OA to a certain extent by decreasing the production of regulatory factors to attenuate the degeneration of cartilage, which partly relieved the effects of DMM on gait, mainly in the hindlimb. Swimming mainly attenuated the thickening and rescued the area of subchondral bone.


Assuntos
Cartilagem Articular , Imobilização , Osteoartrite , Condicionamento Físico Animal , Animais , Camundongos , Cartilagem Articular/fisiopatologia , Modelos Animais de Doenças , Meniscos Tibiais/cirurgia , Osteoartrite/fisiopatologia , Natação , Progressão da Doença
11.
Nanotechnology ; 32(1): 015707, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916664

RESUMO

In order to overcome the drawbacks of Fe3O4 composite samples and greatly increase their performance in microwave absorption, magnetic Fe3O4 spindles coated with dielectric SnO2 nanorods and MnO2 nanoflakes have been successfully synthesized by a four-step simple hydrothermal route. This rationally designed magneto-dielectric ternary nanocomposite will introduce multiple reflection and conductive losses caused by its special multilayer structure and the effective complementarity of dielectric loss and magnetic loss. Therefore, its absorbing performance can be greatly improved. It is notable that the as-prepared Fe3O4@SnO2@MnO2 nanocomposites show a minimum reflection loss value of -50.40 dB at 17.92 GHz at a thickness of 3.9 mm and the absorption bandwidth ranges from 3.62 to 12.08 GHz. The as-prepared Fe3O4@SnO2@MnO2 ternary nanocomposite is expected to be a potential candidate for high-performance microwave-absorbing materials with intensive electromagnetic wave absorption and wide effective absorbing bandwidth.

12.
Acta Pharmacol Sin ; 41(2): 278-285, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31554961

RESUMO

Epigallocatechin gallate (EGCG), a major polyphenol in green tea, exhibits diverse biological activities. Previous studies show that EGCG could effectively suppress HBV gene expression and replication, but the role of EGCG in HBV replication and its underlying mechanisms, especially the signaling pathways involved, remain unclear. In this study we investigated the mechanisms underlying EGCG inhibition on HBV replication with a focus on the signaling pathways. We showed that EGCG (12.5-50 µM) dose-dependently inhibited HBV gene expression and replication in HepG2.2.15 cells. Similar results were observed in HBV mice receiving EGCG (25 mg· kg-1· d-1, ip) for 5 days. In HepG2.2.15 cells, we showed that EGCG (12.5-50 µM) significantly activate ERK1/2 MAPK signaling, slightly activate p38 MAPK and JAK2/STAT3 signaling, while had no significant effect on the activation of JNK MAPK, PI3K/AKT/mTOR and NF-κB signaling. By using specific inhibitors of these signaling pathways, we demonstrated that ERK1/2 signaling pathway, but not other signaling pathways, was involved in EGCG-mediated inhibition of HBV transcription and replication. Furthermore, we showed that EGCG treatment dose-dependently decreased the expression of hepatocyte nuclear factor 4α (HNF4α) both at the mRNA and protein levels, which could be reversed by pretreatment with the ERK1/2 inhibitor PD98059 (20 µM). Moreover, we revealed that EGCG treatment dose-dependently inhibited the activity of HBV core promoter and the following HBV replication. In summary, our results demonstrate that EGCG inhibits HBV gene expression and replication, which involves ERK1/2-mediated downregulation of HNF4α.These data reveal a novel mechanism for EGCG to inhibit HBV gene expression and replication.


Assuntos
Catequina/análogos & derivados , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/administração & dosagem , Antivirais/farmacologia , Catequina/administração & dosagem , Catequina/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Hepatite B/genética , Hepatite B/virologia , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo
13.
J Lipid Res ; 60(10): 1765-1775, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31455613

RESUMO

Sterol-regulated HMG-CoA reductase (HMGCR) degradation and SREBP-2 cleavage are two major feedback regulatory mechanisms governing cholesterol biosynthesis. Reportedly, lanosterol selectively stimulates HMGCR degradation, and cholesterol is a specific regulator of SREBP-2 cleavage. However, it is unclear whether other endogenously generated sterols regulate these events. Here, we investigated the sterol intermediates from the mevalonate pathway of cholesterol biosynthesis using a CRISPR/Cas9-mediated genetic engineering approach. With a constructed HeLa cell line expressing the mevalonate transporter, we individually deleted genes encoding major enzymes in the mevalonate pathway, used lipidomics to measure sterol intermediates, and examined HMGCR and SREBP-2 statuses. We found that the C4-dimethylated sterol intermediates, including lanosterol, 24,25-dihydrolanosterol, follicular fluid meiosis activating sterol, testis meiosis activating sterol, and dihydro-testis meiosis activating sterol, were significantly upregulated upon mevalonate loading. These intermediates augmented both degradation of HMGCR and inhibition of SREBP-2 cleavage. The accumulated lanosterol induced rapid degradation of HMGCR, but did not inhibit SREBP-2 cleavage. The newly synthesized cholesterol from the mevalonate pathway is dispensable for inhibiting SREBP-2 cleavage. Together, these results suggest that lanosterol is a bona fide endogenous regulator that specifically promotes HMGCR degradation, and that other C4-dimethylated sterol intermediates may regulate both HMGCR degradation and SREBP-2 cleavage.


Assuntos
Hidroximetilglutaril-CoA Redutases/metabolismo , Lanosterol/metabolismo , Ácido Mevalônico/metabolismo , Proteólise , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Retroalimentação Fisiológica , Células HeLa , Humanos , Lanosterol/química , Metilação
14.
J Cell Physiol ; 234(11): 19824-19832, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30980397

RESUMO

The cross-talk between cells is very critical for moving forward fracture healing in an orderly manner. Connexin (Cx) 43-formed gap junctions and hemichannels mediate the communication between adjacent cells and cells and extracellular environment. Loss of Cx43 in osteoblasts/osteocytes results in delayed fracture healing. For investigating the role of two channels in osteocytes in bone repair, two transgenic mouse models with Cx43 dominant negative mutants driven by a 10 kb-DMP1 promoter were generated: R76W (gap junctions are blocked, whereas hemichannels are promoted) and Δ130-136 (both gap junctions and hemichannels are blocked). R76W mice (promotion of hemichannels) showed a significant increase of new bone formation, whereas delayed osteoclastogenesis and healing was observed in Δ130-136 (impairment of gap junctions), but not in R76W mice (hemichannel promotion may recover the delay). These results suggest that gap junctions and hemichannels play some similar and cooperative roles in bone repair.


Assuntos
Conexina 43/metabolismo , Consolidação da Fratura , Osteócitos/metabolismo , Animais , Calo Ósseo/patologia , Cartilagem/patologia , Junções Comunicantes/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Osteogênese
15.
J Lipid Res ; 59(3): 507-514, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29353240

RESUMO

The transport of LDL-derived cholesterol from lysosomes to peroxisomes is facilitated by membrane contacts formed between the lysosomal protein synaptotagmin VII and the peroxisomal lipid phosphatidylinositol 4, 5-bisphosphate [PI(4,5)P2]. Here, we used RNA interference to search for regulators of PI(4,5)P2 and to study the effects of altered PI(4,5)P2 homeostasis on cholesterol transport. We found that knockdown of phosphatidylinositol 5-phosphate 4-kinase type-2 α (PIP4K2A) reduced peroxisomal PI(4,5)P2 levels, decreased lysosome-peroxisome membrane contacts, and increased accumulation of lysosomal cholesterol in human SV-589 fibroblasts. Forced expression of peroxisome-localized, kinase-active PIP4K2A in the knockdown cells reduced cholesterol accumulation, and in vitro addition of recombinant PIP4K2A restored membrane contacts. These results suggest that PIP4K2A plays a critical role in intracellular cholesterol transport by upregulating PI(4,5)P2 levels in the peroxisomal membrane. Further research into PIP4K2A activity may inform future therapeutic interventions for managing lysosomal storage disorders.


Assuntos
Colesterol/metabolismo , Homeostase , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Transporte Biológico , Células Cultivadas , Células HEK293 , Humanos
16.
J Cell Biochem ; 119(12): 10327-10337, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30129142

RESUMO

Epidermal growth factor-like domain multiple 7 (EGFL7) is an important sport stimulating factor and motility related factors significantly enhanced the tumor cell metastasis and overexpressed in many cancers, including hepatocellular carcinoma (HCC), associated with tumorigenesis. However, the molecular mechanism by which EGFL7 regulates HCC cell proliferation and apoptosis and the correlation between EGFL7 and cyclin-dependent kinases regulatory subunit 2 (CKS2), which is essential for biological function, have not fully explained. In this study, EGFL7 and CKS2 expression in patients with HCC was measured by real-time polymerase chain reaction and immunohistochemistry. After HCC cells respectively transfected with pLKO.1-EGFL7-shRNA, pLVX-Puro-EGFL7 recombined vector or CKS2 small interfering RNA, cell counting kit-8 and flow cytometry was performed to examine the cell proliferation and apoptosis, respectively, and the expression of ß-catenin, CKS2, CDK2, and cleaved caspase-3 was measured by Western blot analysis. We found that EGFL7 and CKS2 were overexpressed in HCC tissues and a positive correlation was found between them. EGFL7 knockdown markedly inhibited proliferation and promoted apoptosis of HCC cells, along with decreased expression of CKS2 and CDK2, but increased cleaved caspase-3 expression, while EGFL7 overexpression showed an opposite effect. EGFL7 silencing in nude mice also showed decreased tumor growth and altered protein expression similar to its effect in HCC cells in vitro. Importantly, CKS2 silencing significantly inhibited EGFL7-induced HCC cell proliferation and protein expression, and Wnt/ß-catenin signaling pathway inhibitor IWR-1-endo significantly inhibited CKS2 expression in HCC cells. Taken together, EGFL7 promotes HCC cell proliferation and inhibits cell apoptosis through increasing CKS2 expression by activating Wnt/ß-catenin signaling.


Assuntos
Quinases relacionadas a CDC2 e CDC28/genética , Carcinoma Hepatocelular/genética , Proteínas de Transporte/genética , Proteínas de Ciclo Celular/genética , Fatores de Crescimento Endotelial/genética , Neoplasias Hepáticas/genética , Apoptose/genética , Proteínas de Ligação ao Cálcio , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Família de Proteínas EGF , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Via de Sinalização Wnt/genética
17.
Yi Chuan ; 40(9): 693-703, 2018 Sep 20.
Artigo em Zh | MEDLINE | ID: mdl-30369474

RESUMO

With the development of the omic technologies, the acquisition approaches of various biological data on different levels and types are becoming more mature. As a large amount of data will be produced in the process of diagnosis and treatment of diseases, it is necessary to utilize the artificial intelligence such as machine learning to analyze complex, multi-dimensional and multi-scale data and to construct clinical decision support tools. It will provide a method to figure out rapid and effective programs in diagnosis and treatment. In this process, the choice of artificial intelligence seems to be particularly important, such as machine learning. The article reviews the type and algorithm of machine learning used in clinical decision support, such as support vector machines, logistic regression, clustering algorithms, Bagging, random forests and deep learning. The application of machine learning and other methods in clinical decision support has been summarized and classified. The advantages and disadvantages of machine learning are elaborated. It will provide a reference for the selection between machine learning and other artificial intelligence methods in clinical decision support.


Assuntos
Inteligência Artificial/tendências , Sistemas de Apoio a Decisões Clínicas/tendências , Algoritmos , Pesquisa Biomédica , Humanos , Aprendizado de Máquina/tendências
18.
Biochem Biophys Res Commun ; 490(3): 629-635, 2017 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-28630004

RESUMO

Oxidized low-density lipoprotein (ox-LDL) is well known to disrupt normal functionality of endothelium, which plays a prominent role in endothelial dysfunction in many cardiovascular diseases. CO-releasing molecule 2 (CORM-2) is a promising candidate for treatment of cardiovascular diseases. However, it has not been defined whether CORM-2 might improve endothelial injury induced by ox-LDL. The present study was undertaken to determine the regulatory role of CORM-2 in cell injury of ox-LDL-treated human umbilical vein endothelial cells (HUVECs). Our results showed that ox-LDL inhibited the cell proliferation, but promoted apoptosis and release of cytochrome c (cytc) from mitochondrion into cytoplasm, stimulated the cleavage of caspase-3 and mitochondrial permeability transition pore (MPTP) opening. In addition, ox-LDL-incubated HUVECs exhibited excessive reactive oxygen species (ROS), increased protein levels of NADPH oxidase subunits p22phox, p47phox, NOX-2 and activation of Wnt/ß-catenin signaling pathway. However, pretreatment with CORM-2 significantly reduced cell apoptosis, release of cytc from mitochondrion into cytoplasm, MPTP opening and cleavage of caspase-3, suppressed the superoxide anion generation and Wnt/ß-catenin pathway activation in HUVECs response to ox-LDL. Collectively, we provide the evidence that CORM-2 attenuated ox-LDL-mediated endothelial apoptosis and oxidative stress by recovering the mitochondrial function and blocking Wnt/ß-catenin pathway.


Assuntos
Células Endoteliais/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Compostos Organometálicos/farmacologia , Substâncias Protetoras/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Citocromos c/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(3): 783-7, 2017 Mar.
Artigo em Zh, Inglês | MEDLINE | ID: mdl-30148572

RESUMO

The fluorescence quenching agents was characterized with three-dimensional fluorescence and ultraviolet (UV) spectra. When there was Fe (Ⅲ) in the sample, the humic fluorescence would be quenched and their UV spectra were not affected. The variation of fluorescence intensity (I) at Ex/Em=300/510 nm and UV absorbance(A) at UV300 were investigated in the article. The smaller the ratio of fluorescence intensity versus UV absorbance (I/A) is, the higher the fluorescence quencher Fe(Ⅲ) concentration is. According to Stern-Volmer equation I/I0=1-fc×Kc×[c] /(1+Kc×[c] ) and fitted function I/A=f×[k/(cFe3++c)+b] , the fitted fluorescent quenching constant Kc was ranged between 1.08 to 1.15, the ratio of bounded fluorophores versus total fluorophores, i.e. fc, was ranged between 1.10 to 1.14. The ratio of fluorescence intensity and absorbance of humic acid was fitted with Fe(Ⅲ) concentration and the constants were acquired as following: f=0.83~1.19, k=587.19~612.19, c=0.87~0.92, b=-87.09~-46.36. The correlation curve values were 0.99. The Stern-Volmer formula was used to describe the quenching effect of humic acid fluorescence by Fe (Ⅲ). However, due to the fact that the fluorescence intensity I0 without quencher was difficult to acquire during the analysis of practical samples, the fitted function between the ratio of I/A and Fe(Ⅲ) was used to reflect the quenching effect of Fe(Ⅲ) on the fluorescence of humic acid, which was based on the correlations between the fluorescence intensity I0 and ultraviolet absorbance A. The fitted formula was used to predict the iron ions concentration of the resin separated and concentrated samples from wastewater treatment plant and receiving waters. The predicted values were in good accordance with those determined with inductively coupled plasma atomic emission spectroscopy(ICP-AES) method when the iron ion concentration was above 0.4 mg·L-1, which could be used to ascertain the existence of fluorescence quenching agent and their corresponding concentration.


Assuntos
Substâncias Húmicas , Espectrometria de Fluorescência , Compostos Férricos , Corantes Fluorescentes , Íons
20.
Hepatol Res ; 46(10): 1028-36, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26776560

RESUMO

AIM: Accumulating evidence suggests platelets play critical roles in tumor metastasis. Moreover, the role of platelets in metastasis is partially correlated with inflammation. However, evidence regarding the contribution of platelets to hepatocellular carcinoma (HCC) metastasis is lacking. This study investigated the association between platelets and metastatic risk in HCC. METHODS: We used huge HCC (diameter over 10 cm), a tumor subgroup with a strong inflammatory background, as a model to evaluate the potential predictive role of platelets and platelet-related biomarkers for metastasis in HCC patients undergoing transarterial chemoembolization. A logistic regression model was used to analyze risk factors for metastasis. RESULTS: Patients with huge HCC (n = 178) were enrolled, and 24.7% (44/178) of patients had remote metastases after treatment. Univariate analyses showed high platelet counts (P = 0.012), pretreatment platelet-to-lymphocyte ratios (pre-PLR) of 100 or more (P = 0.018) and post-PLR of 100 or more (P = 0.013) were potential risk factors for metastasis. Furthermore, multivariate analyses showed high platelet counts (odds ratio, 2.18; 95% confidence interval, 1.074-4.443; P = 0.031) and platelet-related biomarkers were independent risk factors for HCC metastasis. Particularly, the risk of metastasis in patients with high post-PLR values was significantly greater than patients with low post-PLR values. For tumor response and survival, patients with high platelet counts had faster disease progression (P = 0.002) and worse survival (P < 0.0001). CONCLUSION: High platelet counts increase the extrahepatic metastasis risk of huge HCC undergoing chemoembolization, which supply clinical verification of the association between high platelet counts and HCC metastasis.

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