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1.
Biochem Biophys Res Commun ; 579: 89-96, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34597997

RESUMO

BACKGROUND: Till now, little is known regarding expression pattern and specific roles of lncRNA ASMTL antisense RNA 1 (ASMTL-AS1) in osteosarcoma (OS). Therefore, our current research measured the expression of ASMTL-AS1 in OS, unveiled the roles of ASMTL-AS1 in the modulation of malignant characteristics of OS, and identified the downstream mechanism. METHODS: The regulatory actions of ASMTL-AS1 ablation in OS cells were explored utilizing loss-of-function experiments. Mechanistic studies were implemented utilizing bioinformatics analysis, luciferase reporter assay, RNA immunoprecipitation and rescue experiments. RESULTS: ASMTL-AS1 expression in OS was elevated in both TCGA database and our own cohort. Interfering with ASMTL-AS1 restricted cell proliferation, migration and invasion while increasing cell apoptosis in vitro. Additionally, silencing ASMTL-AS1 blocked tumour growth in vivo. Mechanistically, ASMTL-AS1 could act as a competing endogenous RNA for microRNA-342-3p (miR-342-3p) and inhibit its activity in OS cells, consequently causing an increase in ADAM metallopeptidase domain 9 (ADAM9) levels. Furthermore, inhibiting miR-342-3p or upregulating ADAM9 abated silenced ASMTL-AS1-induced antitumour activity in OS cells. CONCLUSION: ASMTL-AS1 aggravated OS progression by regulating the miR-342-3p/ADAM9 axis.

2.
Endocrinology ; 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34647995

RESUMO

Seminal plasma contains a high concentration of extracellular vesicles (EVs). The heterogeneity of small EVs or the presence of non-vesicular extracellular matter (NV) pose major obstacles in understanding the composition and function of seminal EVs. In this study, we employed high-resolution density gradient fractionation to accurately characterize the composition and function of seminal EVs and NV. We found that the seminal EVs could be divided into three different subtypes, namely high-density EV (EV-H), medium-density EV (EV-M), and low-density EV (EV-L) after purification using iodixanol,while NV was successfully isolated. EVs and NV display different features in size, shape and expression of some classic exosome markers. Both EV-H and NV could markedly promote sperm motility and capacitation compared with EV-M and EV-L, whereas only the NV fraction induced sperm acrosome reaction. Proteomic analysis results showed that EV-H, EV-M, EV-L, and NV had different protein components and were involved in different physiological functions. Further study showed that EV-M might reduce the production of sperm intrinsic reactive oxygen species (ROS) through Glutathione S-transferase Mu 2 (GSTM2).This study provides novel insights into important aspects of seminal EVs constituents and sounder footing to explore their functional properties in male fertility.

3.
Mater Sci Eng C Mater Biol Appl ; 128: 112201, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474813

RESUMO

Tissue engineering technology provides effective alternative treatments for tracheal reconstruction. The formation of a functional microvascular network is essential to support cell metabolism and ensure the long-term survival of grafts. However, given the lack of an identifiable vascular pedicle of the trachea that could be anastomosed to the blood vessels directly in the recipient's neck, successful tracheal transplantation faces significant challenges in rebuilding the adequate blood supply of the graft. Herein, we describe a one-step method to construct microvascularization of tissue-engineered trachea in orthotopic transplantation. Forty rabbit tracheae were decellularized using a vacuum-assisted decellularization (VAD) method. Histological appearance and immunohistochemical (IHC) analysis demonstrated efficient removal of cellular components and nuclear material from natural tissue, which was also confirmed by 4'-6-diamidino-2-phenylindole(DAPI) staining and DNA quantitative analysis, thus significantly reducing the antigenicity. Scanning electron microscopy (SEM), immunofluorescence (IF) analysis, GAG and collagen quantitative analysis showed that the hierarchical structures, composition and integrity of the extracellular matrix (ECM) were protected. IF analysis also demonstrated that basic fibroblast growth factor (b-FGF) was preserved during the decellularization process, and also exerted biocompatibility and proangiogenic properties by the chick chorioallantoic membrane(CAM) assay. Xenotransplantation assays indicated that the VAD tracheal matrix would no longer induced inflammatory reactions implanted in the body for 4 weeks after treated by VAD more than 16 h. Furthermore, we seeded the matrix with bone marrow-derived endothelial cells (BMECs) in vitro and performed in vivo tracheal patch repair assays to prove the biocompatibility and neovascularization of VAD-treated tracheal matrix, and the formation of a vascular network around the patch promoted the crawling of surrounding ciliated epithelial cells to the surface of the graft. We conclude that this natural VAD tracheal matrix is non-immunogenic and no inflammatory reactions in vivo transplantation. Seeding with BMECs on the grafts and then performing orthotopic transplantation can effectively promote the microvascularization and accelerate the native epithelium cells crawling to the lumen of the tracheal graft.


Assuntos
Engenharia Tecidual , Traqueia , Animais , Células Endoteliais , Matriz Extracelular , Coelhos , Tecidos Suporte
4.
FASEB J ; 35(10): e21925, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34569663

RESUMO

In mammalian testes, extensive remodeling of the microtubule (MT) and actin cytoskeletons takes place in Sertoli cells across the seminiferous epithelium to support spermatogenesis. However, the mechanism(s) involving regulatory and signaling proteins remains poorly understood. Herein, A-kinase anchoring protein 9 (AKAP9, a member of the AKAP multivalent scaffold protein family) was shown to be one of these crucial regulatory proteins in the rat testis. Earlier studies have shown that AKAP9 serves as a signaling platform by recruiting multiple signaling and regulatory proteins to create a large protein complex that binds to the Golgi and centrosome to facilitate the assembly of the MT-nucleating γ-tubulin ring complex to initiate MT polymerization. We further expanded our earlier studies based on a Sertoli cell-specific AKAP9 knockout mouse model to probe the function of AKAP9 by using the techniques of immunofluorescence analysis, RNA interference (RNAi), and biochemical assays on an in vitro primary Sertoli cell culture model, and an adjudin-based animal model. AKAP9 robustly expressed across the seminiferous epithelium in adult rat testes, colocalizing with MT-based tracks, and laid perpendicular across the seminiferous epithelium, and prominently expressed at the Sertoli-spermatid cell-cell anchoring junction (called apical ectoplasmic specialization [ES]) and at the Sertoli cell-cell interface (called basal ES, which together with tight junction [TJ] created the blood-testis barrier [BTB]) stage specifically. AKAP9 knockdown in Sertoli cells by RNAi was found to perturb the TJ-permeability barrier through disruptive changes in the distribution of BTB-associated proteins at the Sertoli cell cortical zone, mediated by a considerable loss of ability to induce both MT polymerization and actin filament bundling. A considerable decline in AKAP9 expression and a disruptive distribution of AKAP9 across the seminiferous tubules was also noted during adjudin-induced germ cell (GC) exfoliation in this animal model, illustrating AKAP9 is essential to maintain the homeostasis of cytoskeletons to maintain Sertoli and GC adhesion in the testis.

5.
Commun Biol ; 4(1): 1030, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34475516

RESUMO

Techniques involving three-dimensional (3D) tissue structure reconstruction and analysis provide a better understanding of changes in molecules and function. We have developed AutoCUTS-LM, an automated system that allows the latest advances in 3D tissue reconstruction and cellular analysis developments using light microscopy on various tissues, including archived tissue. The workflow in this paper involved advanced tissue sampling methods of the human cerebral cortex, an automated serial section collection system, digital tissue library, cell detection using convolution neural network, 3D cell reconstruction, and advanced analysis. Our results demonstrated the detailed structure of pyramidal cells (number, volume, diameter, sphericity and orientation) and their 3D spatial organization are arranged in a columnar structure. The pipeline of these combined techniques provides a detailed analysis of tissues and cells in biology and pathology.

6.
Molecules ; 26(18)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34577169

RESUMO

Artemisinin (also known as Qinghaosu), an active component of the Qinghao extract, is widely used as antimalarial drug. Previous studies reveal that artemisinin and its derivatives also have effective anti-inflammatory and immunomodulatory properties, but the direct molecular target remains unknown. Recently, several reports mentioned that myeloid differentiation factor 2 (MD-2, also known as lymphocyte antigen 96) may be the endogenous target of artemisinin in the inhibition of lipopolysaccharide signaling. However, the exact interaction between artemisinin and MD-2 is still not fully understood. Here, experimental and computational methods were employed to elucidate the relationship between the artemisinin and its inhibition mechanism. Experimental results showed that artemether exhibit higher anti-inflammatory activity performance than artemisinin and artesunate. Molecular docking results showed that artemisinin, artesunate, and artemether had similar binding poses, and all complexes remained stable throughout the whole molecular dynamics simulations, whereas the binding of artemisinin and its derivatives to MD-2 decreased the TLR4(Toll-Like Receptor 4)/MD-2 stability. Moreover, artemether exhibited lower binding energy as compared to artemisinin and artesunate, which is in good agreement with the experimental results. Leu61, Leu78, and Ile117 are indeed key residues that contribute to the binding free energy. Binding free energy analysis further confirmed that hydrophobic interactions were critical to maintain the binding mode of artemisinin and its derivatives with MD-2.

7.
Sci Adv ; 7(33)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34380613

RESUMO

Human trophoblast stem cells (hTSCs) provide a valuable model to study placental development and function. While primary hTSCs have been derived from embryos/early placenta, and transdifferentiated hTSCs from naïve human pluripotent stem cells (hPSCs), the generation of hTSCs from primed PSCs is problematic. We report the successful generation of TSCs from primed hPSCs and show that BMP4 substantially enhances this process. TSCs derived from primed hPSCs are similar to blastocyst-derived hTSCs in terms of morphology, proliferation, differentiation potential, and gene expression. We define the chromatin accessibility dynamics and histone modifications (H3K4me3/H3K27me3) that specify hPSC-derived TSCs. Consistent with low density of H3K27me3 in primed hPSC-derived hTSCs, we show that knockout of H3K27 methyltransferases (EZH1/2) increases the efficiency of hTSC derivation from primed hPSCs. Efficient derivation of hTSCs from primed hPSCs provides a simple and powerful model to understand human trophoblast development, including the pathogenesis of trophoblast-related disorders, by generating disease-specific hTSCs.

8.
Adv Exp Med Biol ; 1288: 161-173, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34453736

RESUMO

Non-obstructive azoospermia (NOA) and obstructive azoospermia (OA) are two common causes of infertility that affect a considerable number of men. However, few studies were performed to understand the molecular etiology of these disorders. Studies based on bioinformatics and genetic analyses in recent years, however, have yielded insightful information and have identified a number of genes that are involved in these disorders. In this review, we briefly summarize and evaluate these findings. We also discuss findings based on epigenetic modifications of sperm DNAs that affect a number of genes pertinent to NOA and OA. The information summarized in this Chapter should be helpful to investigators in future functional studies of NOA and OA.


Assuntos
Azoospermia , Infertilidade Masculina , Azoospermia/genética , Testes Genéticos , Humanos , Infertilidade Masculina/genética , Masculino , Espermatozoides , Testículo
9.
Adv Exp Med Biol ; 1288: 131-159, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34453735

RESUMO

Unlike the intermediate filament- and septin-based cytoskeletons which are apolar structures, the microtubule (MT) and actin cytoskeletons are polarized structures in mammalian cells and tissues including the testis, most notable in Sertoli cells. In the testis, these cytoskeletons that stretch across the epithelium of seminiferous tubules and lay perpendicular to the basement membrane of tunica propria serve as tracks for corresponding motor proteins to support cellular cargo transport. These cargoes include residual bodies, phagosomes, endocytic vesicles and most notably developing spermatocytes and haploid spermatids which lack the ultrastructures of motile cells (e.g., lamellipodia, filopodia). As such, these developing germ cells require the corresponding motor proteins to facilitate their transport across the seminiferous epithelium during the epithelial cycle of spermatogenesis. Due to the polarized natures of these cytoskeletons with distinctive plus (+) and minus (-) end, directional cargo transport can take place based on the use of corresponding actin- or MT-based motor proteins. These include the MT-based minus (-) end directed motor proteins: dyneins, and the plus (+) end directed motor proteins: kinesins, as well as the actin-based motor proteins: myosins, many of which are plus (+) end directed but a few are also minus (-) end directed motor proteins. Recent studies have shown that these motor proteins are essential to support spermatogenesis. In this review, we briefly summarize and evaluate these recent findings so that this information will serve as a helpful guide for future studies and for planning functional experiments to better understand their role mechanistically in supporting spermatogenesis.


Assuntos
Dineínas , Espermatogênese , Animais , Masculino , Miosinas , Epitélio Seminífero , Células de Sertoli , Espermátides
10.
Ultrasound Med Biol ; 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34456083

RESUMO

This study aimed to investigate left atrium (LA) strain components in the assessment of cardiac function and its clinical correlates in pre-eclampsia (PE). With the use of speckle tracking echocardiography, phasic LA strain and (LASr)/(E/e'), the surrogate of LA compliance, were compared between healthy pregnant women (n = 70) and those with PE (n = 146) and among different diastolic dysfunction (DD) grades in PE. Receiver operating characteristic curves and logistic regression analysis were used to identify the role of strain components in distinguishing DD grades and predicting cardiac complications. LA reservoir strain, conduit strain and LA compliance reduced significantly in PE (p < 0.01). LASr/(E/e') gradually decreased with worsening DD and LASr/(E/e') <3.40 was the independent risk factor for cardiac events in PE (p < 0.01). This study observed significantly decreased LA strain and compliance in PE. Notably, LA compliance decreased progressively with the severity of DD, and LASr/(E/e') <3.40 is the independent risk factor for cardiac complications during PE pregnancy.

11.
J Bioenerg Biomembr ; 53(5): 561-572, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34424449

RESUMO

BACKGROUND: Recently, more and more circular RNAs (circRNAs) have been identified in osteogenesis. In this study, we aimed to explore the effect of circ_FBLN1 on the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs). METHODS: The protein levels of osteogenesis-related genes, let-7i-5p, frizzled class receptor 4 (FZD4), Ki67, Wnt6 and ß-catenin were measured by western blot assay. The levels of circ_FBLN1, FBLN1 mRNA and FZD4 mRNA were determined by quantitative real-time polymerase chain reaction (qRT-PCR) assay. The feature of circ_FBLN1 was investigated by RNase R and Actinomycin D assays. Cell proliferation ability was evaluated by colony formation assay and 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The targeting relationship between let-7i-5p and circ_FBLN1 or FZD4 was verified by dual-luciferase reporter assay. RESULTS: Circ_FBLN1 level was enhanced during the osteogenic differentiation of hBMSCs. Silencing of circ_FBLN1 repressed cell proliferation and osteogenic differentiation in hBMSCs. For mechanism analysis, circ_FBLN1 was found to act as a sponge for let-7i-5p and FZD4 served as a direct target gene of let-7i-5p. Let-7i-5p was downregulated during the osteogenic differentiation of hBMSCs and let-7i-5p inhibition restored the effects of circ_FBLN1 knockdown on the proliferation and osteogenesis of hBMSCs. Moreover, let-7i-5p overexpression suppressed cell proliferation and osteogenesis in hBMSCs through targeting FZD4. In addition, circ_FBLN1 knockdown reduced the levels of Wnt6 and ß-catenin in hBMSCs, indicating the inactivation of Wnt/ß-catenin pathway. CONCLUSION: Knockdown of circ_FBLN1 inhibited the proliferation and osteogenesis of hBMSCs by regulating let-7i-5p/FZD4 axis and repressing Wnt/ß-catenin pathway.

12.
Turk Neurosurg ; 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-34374979

RESUMO

AIM: The purpose of this study was to investigate the safety and efficacy of endoport-assisted endoscopic techniques when used to remove intraventricular lesions. MATERIAL AND METHODS: Data of patients with intraventricular lesions who were surgically treated by endoport-assisted endoscopic resection between January 2018 and February 2019 were retrospectively reviewed. The surgical procedures, complications and outcomes were analyzed. RESULTS: A total of 11 patients, with a mean age of 33 years (5-70 years) were included in the study. The mean Karnofsky Performance Scale (KPS) score evaluated on admission was 50.0 ± 7.0. Lesions located in the unilateral ventricle, the third ventricle and multiple sites of ventricles were recorded in 7, 2 and 2 patients, respectively. The average lesion size was 3.4 ± 0.4 cm (2-6 cm). Gross-total removal of all lesions was achieved, and all patients experienced a stable recovery after operations except for one hemorrhage and one visual field defect occurring in two patients in the early postoperative period. With a follow-up of 6-19 months, dysfunctions and complications occurring pre- or postoperation gradually recovered to different degrees. The mean KPS score was 85.5 ± 4.3 at the last follow-up, and no tumor recurrence was observed in any of the patients. CONCLUSION: Endoport-assisted endoscopic techniques could be a simple, minimally invasive surgical method in the resection of lesions located in the lateral ventricle, the third ventricle, or both with acceptable surgical complications occurring in patients.

13.
Sci Rep ; 11(1): 16281, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381064

RESUMO

Essential oils and their active components, referred here as plant derived antimicrobials (PDAs), have been used for their antimicrobial, anti-inflammatory and antioxidant properties. Many reports also document PDAs' cytotoxic effects on cancerous cells, raising the hope that they could be used for cancer treatments. Due to the lack of specificity, we hypothesize that PDAs are cytotoxic to both cancerous and non-cancerous cells. Trans-cinnamaldehyde (TCA), carvacrol, and eugenol were assessed for their cytotoxicity on cancerous HeLa cells and normal skin fibroblasts (CCD-1123Sk, CCD) by MTT and LDH assays, flow cytometry, and reverse transcription quantitative PCR (RT-qPCR). After 24 h of treatment, carvacrol and TCA significantly decreased cell viability (by more than 50%) at 100 µg/ml, whereas eugenol was ineffective up to 400 µg/ml. Cell detachment and significantly increased apoptosis were observed with 100 µg/ml of TCA on both cell types. RT-qPCR for apoptotic genes (BCL2, CASP3 and CASP8) and necrosis genes (MLKL, RIPK1 and RIPK3) did not show significant differences between control and treated cells of both types, with the exception of eugenol-treated HeLa cells in which expression of BCL2, MLKL and RIPK1 was significantly higher than controls. Taken together, we conclude that the three PDAs studied here exhibited similar cytotoxic effects on both cancerous and non-cancerous cells.

14.
Cell Death Differ ; 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34420035

RESUMO

The methyl-CpG-binding domain 2 (MBD2) interprets DNA methylome-encoded information through binding to the methylated CpG DNA, by which it regulates target gene expression at the transcriptional level. Although derailed DNA methylation has long been recognized to trigger or promote autoimmune responses in type 1 diabetes (T1D), the exact role of MBD2 in T1D pathogenesis, however, remains poorly defined. Herein, we generated an Mbd2 knockout model in the NOD background and found that Mbd2 deficiency exacerbated the development of spontaneous T1D in NOD mice. Adoptive transfer of Mbd2-/- CD4 T cells into NOD.scid mice further confirmed the observation. Mechanistically, Th1 stimulation rendered the Stat1 promoter to undergo a DNA methylation turnover featured by the changes of DNA methylation levels or patterns along with the induction of MBD2 expression, which then bound to the methylated CpG DNA within the Stat1 promoter, by which MBD2 maintains the homeostasis of Th1 program to prevent autoimmunity. As a result, ectopic MBD2 expression alleviated CD4 T cell diabetogenicity following their adoptive transfer into NOD.scid mice. Collectively, our data suggest that MBD2 could be a viable target to develop epigenetic-based therapeutics against T1D in clinical settings.

15.
Front Immunol ; 12: 690783, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335595

RESUMO

Type 1 diabetes (T1D) is characterized by the unresolved autoimmune inflammation and islet ß cell destruction. The islet resident antigen-presenting cells (APCs) including dendritic cells and macrophages uptake and process the ß cell-derived antigens to prime the autoreactive diabetogenic T cells. Upon activation, those autoreactive T cells produce copious amount of IFN-γ, TNF-α and IL-1ß to induce ß cell stress and death. Autoimmune attack and ß cell damage intertwine together to push forward this self-destructive program, leading to T1D onset. However, ß cells are far beyond a passive participant during the course of T1D development. Herein in this review, we summarized how ß cells are actively involved in the initiation of autoimmune responses in T1D setting. Specifically, ß cells produce modified neoantigens under stressed condition, which is coupled with upregulated expression of MHC I/II and co-stimulatory molecules as well as other immune modules, that are essential properties normally exhibited by the professional APCs. At the cellular level, this subset of APC-like ß cells dynamically interacts with plasmacytoid dendritic cells (pDCs) and manifests potency to activate autoreactive CD4 and CD8 T cells, by which ß cells initiate early autoimmune responses predisposing to T1D development. Overall, the antigen-presenting function of ß cells helps to explain the tissue specificity of T1D and highlights the active roles of structural cells played in the pathogenesis of various immune related disorders.

16.
Anal Chem ; 93(29): 10075-10083, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34270209

RESUMO

Metabolomics is a powerful and essential technology for profiling metabolic phenotypes and exploring metabolic reprogramming, which enables the identification of biomarkers and provides mechanistic insights into physiology and disease. However, its applications are still limited by the technical challenges particularly in its detection sensitivity for the analysis of biological samples with limited amount, necessitating the development of highly sensitive approaches. Here, we developed a highly sensitive liquid chromatography tandem mass spectrometry method based on a 3-nitrophenylhydrazine (3-NPH) derivatization strategy that simultaneously targets carbonyl, carboxyl, and phosphoryl groups for targeted metabolomic analysis (HSDccp-TM) in biological samples. By testing 130 endogenous metabolites including organic acids, amino acids, carbohydrates, nucleotides, carnitines, and vitamins, we showed that the derivatization strategy resulted in significantly improved detection sensitivity and chromatographic separation capability. Metabolic profiling of merely 60 oocytes and 5000 hematopoietic stem cells primarily isolated from mice demonstrated that this method enabled routine metabolomic analysis in trace amounts of biospecimens. Moreover, the derivatization strategy bypassed the tediousness of inferring the MS fragmentation patterns and simplified the complexity of monitoring ion pairs of metabolites, which greatly facilitated the metabolic flux analysis (MFA) for glycolysis, the tricarboxylic acid (TCA) cycle, and pentose phosphate pathway (PPP) in cell cultures. In summary, the novel 3-NPH derivatization-based method with high sensitivity, good chromatographic separation, and broad coverage showed great potential in promoting metabolomics and MFA, especially in trace amounts of biospecimens.


Assuntos
Metabolômica , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida , Camundongos , Fenil-Hidrazinas
17.
Genes Dev ; 35(15-16): 1175-1189, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34301767

RESUMO

Knowledge of how Mediator and TFIID cross-talk contributes to promoter-enhancer (P-E) communication is important for elucidating the mechanism of enhancer function. We conducted an shRNA knockdown screen in murine embryonic stem cells to identify the functional overlap between Mediator and TFIID subunits on gene expression. Auxin-inducible degrons were constructed for TAF12 and MED4, the subunits eliciting the greatest overlap. Degradation of TAF12 led to a dramatic genome-wide decrease in gene expression accompanied by destruction of TFIID, loss of Pol II preinitiation complex (PIC) at promoters, and significantly decreased Mediator binding to promoters and enhancers. Interestingly, loss of the PIC elicited only a mild effect on P-E looping by promoter capture Hi-C (PCHi-C). Degradation of MED4 had a minor effect on Mediator integrity but led to a consistent twofold loss in gene expression, decreased binding of Pol II to Mediator, and decreased recruitment of Pol II to the promoters, but had no effect on the other PIC components. PCHi-C revealed no consistent effect of MED4 degradation on P-E looping. Collectively, our data show that TAF12 and MED4 contribute mechanistically in different ways to P-E communication but neither factor appears to directly control P-E looping, thereby dissociating P-E communication from physical looping.

18.
Int Immunopharmacol ; 98: 107906, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34198238

RESUMO

The functional state of T cells is diverse and under dynamic control for adapting to the changes of microenvironment. Reversible protein phosphorylation represents an important post-translational modification that not only involves in the immediate early response of T cells, but also affects their functionality in the long run. Perturbation of global phosphorylation profile and/or phosphorylation of specific signaling nodes result in aberrant T cell activity. Dual specific phosphatases (DUSPs), which target MAPKs and beyond, have increasingly been emerged as a versatile regulator in T cell biology. Herein in this mini review, we sought to summarize and discuss the impact of DUSP proteins on the regulation of effector T cell activity, T cell polarization, regulatory T cell development and T cell senescence/exhaustion. Given the distinctive engagement of each DUSP member under various disease settings such as chronic infection, autoimmune disorders, cancer and age-related diseases, DUSP proteins likely hold the promise to become a druggable target other than the existing therapeutics that are predominantly by manipulating protein kinase activity.

19.
Lipids Health Dis ; 20(1): 71, 2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34273996

RESUMO

BACKGROUND: Some previous studies on different populations have yielded inconsistent findings with respect to the relationship between levels of high-density lipoprotein cholesterol (HDL-C) and future type 2 diabetes mellitus (T2DM) incidence. This study was designed to gain further insight into this relationship through a cohort study with a 25-year follow-up duration. METHODS: In total, 1462 individuals that were 55 years of age or older and were free of T2DM at baseline were enrolled in the present study. T2DM incidence among this study population was detected through self-reported diagnoses or the concentration of fasting plasma glucose. The data were derived from nine surveys conducted from 1992 to 2017. The correlation between HDL-C levels and the T2DM risk was assessed through Cox proportional-hazards model and proportional hazards model for the sub-distribution with time-dependent variables. RESULTS: Over the follow-up period, 120 participants were newly diagnosed with new-onset T2DM. When research participants were separated into four groups on the basis for quartiles of their levels of HDL-C measured at baseline, and incidence of diabetes declined with higher baseline HDL-C levels at 12.60, 9.70, 5.38, and 5.22 per 1000 person-years, respectively. Adjusted hazard ratios (HRs) were 0.98 (95% confidence interval [CI]: 0.62-1.55), 0.48 (95% CI: 0.27-0.85) and 0.44 (95% CI: 0.25-0.80) for individuals with HDL-C levels within the 1.15-1.39, 1.40-1.69, and ≥ 1.70 mmol/L ranges relative to participants with HDL-C levels < 1.15 mmol/L. Multiple sensitivity analyses similarly revealed reduced risk of diabetes incidence with increased HDL-C levels. Incorporating the levels of HDL-C into a multivariate model significantly enhanced the overall power of the predictive model (P values were 0.0296, 0.0011, respectively, for 5- and 10-year risk of diabetes). CONCLUSIONS: Levels of HDL-C were independently and negatively associated with the risk of the new-onset T2DM among middle-aged and elderly Chinese.

20.
Signal Transduct Target Ther ; 6(1): 288, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326308

RESUMO

The COVID-19 pandemic poses a global threat to public health and economy. The continuously emerging SARS-CoV-2 variants present a major challenge to the development of antiviral agents and vaccines. In this study, we identified that EK1 and cholesterol-coupled derivative of EK1, EK1C4, as pan-CoV fusion inhibitors, exhibit potent antiviral activity against SARS-CoV-2 infection in both lung- and intestine-derived cell lines (Calu-3 and Caco2, respectively). They are also effective against infection of pseudotyped SARS-CoV-2 variants B.1.1.7 (Alpha) and B.1.1.248 (Gamma) as well as those with mutations in S protein, including N417T, E484K, N501Y, and D614G, which are common in South African and Brazilian variants. Crystal structure revealed that EK1 targets the HR1 domain in the SARS-CoV-2 S protein to block virus-cell fusion and provide mechanistic insights into its broad and effective antiviral activity. Nasal administration of EK1 peptides to hACE2 transgenic mice significantly reduced viral titers in lung and intestinal tissues. EK1 showed good safety profiles in various animal models, supporting further clinical development of EK1-based pan-CoV fusion inhibitors against SARS-CoV-2 and its variants.


Assuntos
Antivirais , COVID-19/tratamento farmacológico , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/química , Antivirais/farmacologia , Células CACO-2 , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Humanos , Camundongos Transgênicos , Domínios Proteicos , SARS-CoV-2/química , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
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