简介:AbstractSkeletal muscle plays an essential role in generating the mechanical force necessary to support the movement of our body and daily exercise. Compared with cardiac and smooth muscle, in mammals, skeletal muscle exhibits remarkable regenerative capacity in response to damage. Muscle stem cells, also known as satellite cells, directly contribute to regeneration. Here, we review primary and secondary myogenesis processes with a focus on muscle stem cells, as well as the function and regulation of muscle stem cells in adult muscle regeneration in mammals.
简介:AbstractChemotherapy is often used for female malignancies, but it can increase the risk of premature ovarian failure in women of reproductive age through different mechanisms. Therefore, how to protect ovarian function and preserve fertility has attracted great attention of oncologists and gynecologists. Recently, umbilical cord mesenchymal stem cells (UCMSCs) have been extensively studied in the field of regenerative medicine. Compared with mesenchymal stem cells (MSCs) from other sources, UCMSCs have a broader application potential due to their properties of lower immunogenicity, fewer ethical issues, and non-invasive collection. Paracrine is one of the most important therapeutic mechanisms of UCMSCs, which can exert anti-inflammatory, anti-fibrosis, anti-oxidative stress, immune regulation, and other therapeutic effects. Studies in animal models have shown that UCMSCs can restore ovarian function after chemotherapy injury. However, most of the relevant researches are still in the preclinical stage. In this article, the mechanism of chemotherapy-induced ovarian failure will be overviewed, and the clinical application potential of UCMSCs in chemotherapeutic ovarian injury will be discussed.
简介:AbstractObjective:To elucidate the epidermal melanocyte distribution according to sex, age, and body part with the goal of providing benchmark data for the diagnosis and therapeutic effect evaluation of pigmentary skin diseases.Methods:Epidermal melanocytes and keratinocytes were assessed using direct immunofluorescence staining, and the melanocyte density and epidermal thickness were calculated. The obtained data were statistically analyzed using SPSS Version 20.0 software. An independent-samples t test was used to compare the data between two groups, while data among three or more groups were compared by one-way analysis of variance. Data correlations were evaluated using Pearson correlation analysis.Results:Melanocytes were uniformly distributed among the keratinocytes in the basal layer, and the average ratio of melanocytes to keratinocytes was 1:7. Among them, the ratio in males was 1:6.5 and that in females was 1:7.4, with no significant difference (P= 0.127). The melanocyte density gradually declined as age increased; the ratio was 1:5.8 before 50 years of age without an obvious downtrend. The average melanocyte density was 1:7.9 within 51 to 65 years of age and 1:8.5 at >65 years of age, and the difference was statistically significant (P < 0.01). Obvious differences were found in the melanocyte density among different body parts; in descending order, these densities were as follows: face (1:4.0) >neck (1:5.1) >hip (1:5.7) >upper limb (1:7.4) >lower limb (1:8.3) >lower back (1:9.2) >thorax and abdomen (1:9.9). The melanocyte density was not related to the epidermal thickness.Conclusion:The melanocyte density showed a declining trend with age and significantly changed after 50 years of age. The melanocyte density was associated with body part; specifically, the density in the face, neck, and hip was higher than that in the limbs and torso. However, the melanocyte density was not associated with sex or epidermal thickness.
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简介:AbstractBackground:Shenque (CV8) acupoint is located on the navel and has been therapeutically used for more than 2000 years in Traditional Chinese Medicine (TCM). However, clinical research on the underlying therapeutic molecular mechanisms of the CV8 acupoint lags far behind. This study aimed to study the mechanisms of umbilical acupoint therapy by using stem cells.Methods:The morphological characteristics of CV8 acupoint were detected under a stereomicroscope using hematoxylin and eosin (H&E) staining. Oil Red, Masson, and immunohistochemical staining on multi-layered slices were used to identify the type of cells at the CV8 acupoint. Cell proliferation was measured by a cell counting kit-8 (CCK-8) method. Flow cytometry and immunohistochemistry were used for cell identification. Induced differentiation was used to compare the differentiation of cells derived from CV8 acupoint and non-acupoint somatic stem cells into other cell types, such as osteogenic, adipogenic, and neural stem cell-like cells.Results:Morphological observations showed that adipose tissues at the linea alba of the CV8 acupoint in mice had a mass-like distribution. Immunohistochemical staining confirmed the distribution of stem cell antigen-1 (Sca-1) positive cells in the multi-layered slices of CV8 acupoint tissues. Cells isolated from adipose tissues at the CV8 acupoint exhibited high expression of Sca-1 and CD44 and low expression of CD31 and CD34, and these cells possessed osteogenic, adipogenic, and neurogenic stem cell-like cell differentiation ability. The cell proliferation (day 4: 0.5138 ± 0.0111 vs. 0.4107 ± 0.0180, t = 8.447, P = 0.0011; day 5: 0.6890 ± 0.0070 vs. 0.5520 ± 0.0118, t = 17.310, P < 0.0001; day 6: 0.7320 ± 0.0090 vs. 0.6157 ± 0.0123, t = 13.190, P = 0.0002; and day 7: 0.7550 ± 0.0050 vs. 0.6313 ± 0.0051, t = 42.560, P < 0.0001), adipogenic ([9.224 ± 0.345]% vs. [3.933 ± 1.800]%, t = 5.000, P = 0.0075), and neurogenic stem cell-like cell differentiation (diameter < 50 μm: 7.2000 ± 1.3040 vs. 2.6000 ± 0.5477, t = 7.273, P < 0.0001; diameter 50-100 μm: 2.6000 ± 0.5477 vs. 1.0000 ± 0.7071, t = 4.000, P = 0.0039; and diameter >100 μm: 2.6000 ± 0.5477 vs. 0.8000 ± 0.8367, t = 4.025, P = 0.0038) were significantly enhanced in somatic stem cells derived from the CV8 acupoint compared to somatic stem cells from the groin non-acupoint. However, cells possessed significantly weaker osteogenicity ([2.697 ± 0.627]% vs. [7.254 ± 0.958]%, t = 6.893, P = 0.0023) in the CV8 acupoint group.Conclusions:Our study showed that CV8 acupoint was rich with adipose tissues that contained abundant somatic stem cells. The biological examination of somatic stem cells derived from the CV8 acupoint provided novel insights for future research on the mechanisms of umbilical therapy.
简介:AbstractObjective:Liver cancer stem cells (CSCs) are the culprits of hepatocellular carcinoma metastasis and recurrence. Only by eliminating tumor stem cells can malignant tumors be fundamentally cured. This study aimed to identify the role and underlying mechanism of aberrant Collagen Type XIV Alpha 1 Chain (COL14A1) overexpression in liver CSCs, and improve understanding of the molecular basis of hepatocellular carcinoma metastasis and recurrence.Methods:First, quantitative real-time polymerase chain reaction was used to confirm aberrant high-expression of COL14A1 in liver CSCs. Next, interference experiments were performed to determine the key role of COL14A1. To explore the mechanism of COL14A1 overexpression in liver CSCs, putative microRNA (miRNAs) targeting COL14A1 were analyzed using the miRTarBase database. Next, quantitative real-time polymerase chain reaction, western blotting, and luciferase reporter assays were performed to verify the interaction between miR-7108-3p and COL14A1. Lastly, key target proteins of the COL14A1-extracellular-regulated signal kinase (ERK) signaling pathway were identified through western blotting analysis. This study was approved by the Ethics Committee of Shanghai Fourth People’s Hospital, Tongji University School of Medicine, China (approval No. 2019tjdx17) on February 21, 2019.Results:COL14A1 is abnormally highly expressed in liver CSCs, which is necessary for liver CSCs to maintain their self-renewal capability. Mechanistically, COL14A1 is post-transcriptionally regulated by miR-7108-3p in a negative manner. Low expression of miR-7108-3p increased translation of COL14A1, which subsequently activated ERK signaling, ultimately maintaining the self-renewal and stem cell-like properties of liver CSCs.Conclusion:COL14A1, which is negatively regulated by miR-7108-3p, was found to play a crucial role in maintaining the self-renewal and stem cell-like properties of liver CSCs through activation of ERK signaling.
简介:AbstractBackground:Our previous studies showed that topical application of mesenchymal stem cells (MSCs) improved functional recovery in rat traumatic brain injury (TBI) model, and hypoxic precondition further enhanced the therapeutic effects of MSCs. There was no previous study on the attenuation of cerebral edema by MSCs. We investigated whether topical application of normoxic and hypoxic MSCs could reduce cerebral edema in an experimental TBI model.Methods:Two million normoxic (N = 24) and hypoxic (N = 24) MSCs were applied topically to exposed the cerebral cortex in a controlled cortical impact (CCI) model. The MSCs were fixed in position with fibrin glue. No treatment was given to control animals (TBI only: n = 24). After surgery, four animals in each group were sacrificed daily (day 1 to day 6) for edema evaluation. Normal animals without TBI were used as reference (n = 4). The expressions of GFAP, AQP4, and MMP9 were also investigated by immunofluorescence staining and RT-PCR at day 3.Results:The edema peaked within 3 days after TBI. Compared with the control, hypoxic MSCs reduced brain water content significantly (p < 0.05). Both hypoxic and normoxic MSCs downregulated the expression of MMP9 and normalized AQP4 distribution to astrocyte end feet.Conclusion:Our preliminary study showed that topical application of hypoxic MSCs suppressed both vasogenic and cytotoxic edema formation.
简介:AbstractBackground:Pharmacological factors used to induce insulin resistance (IR) in in vitro models may not mimic the full in vivo features of type 2 diabetes mellitus (T2DM). This study aimed to examine the ability of diabetic serum (DS) to induce IR and investigate whether adipose-derived mesenchymal stem cell conditioned medium (ADMSC-CM) reverses DS-induced IR.Methods:DS was obtained from newly diagnosed T2DM patients. IR was induced in differentiated 3T3-L1 cells by employing dexamethasone, tumor necrosis factor alpha (TNF-α), palmitate and DS. Glucose uptake (2-[N-[7-nitrobenz-2-oxa-1,3-diazol-4-yl] amino]-2-deoxyglucose(2-NBDG) uptake assay), intracellular levels of reactive oxygen species (ROS), and superoxide radicals (O2-) (fluorescence microscopy and fluorometry) were analyzed in control and experimental samples. mRNA expression of key genes involved in glucose transport and inflammation were analyzed by using reverse transcription polymerase chain reaction (RT-PCR). Pro-inflammatory cytokines and phospho-insulin receptor substrate (IRS) (Ser-307) protein expression were analyzed by fluorescence activated cell sorter analysis. Statistical significance was determined by using one-way ANOVA followed by Tukey's multiple comparison tests.Results:ADMSC-CM significantly increased the DS-mediated decrease in 2-NBDG uptake (11.01 ± 0.50 vs. 7.20 ± 0.30, P < 0.01) and reduced DS-driven ROS (fluorescence count, 6.35 ± 0.46 vs. 9.80 ± 0.10, P < 0.01) and O2- (fluorescence count, 3.00 ± 0.10 vs. 4.60 ± 0.09, P < 0.01) production. Further, the ADMSC-CM restored DS-induced down regulation GLUT4 (1.52- fold, P < 0.05) as well as the up-regulation of PPARγ (0.35-fold, P < 0.01), and IKKβ (0.37-fold, P < 0.01) mRNA, and phospho-IRS (Ser-307) protein expression compared to the baseline (median fluorescence intensity, 88,192 ± 2720 vs. 65,450 ± 3111, P < 0.01). DS induced IR, similar to the traditionally used pharmacological factors, namely dexamethasone, TNF-α, and palmitate, which can be attributed to the significantly higher pro-inflammatory cytokines levels (TNF-α (2.28 ± 0.03 pg/mL vs. 2.38 ± 0.03 pg/mL, P < 0.01), interleukin 6 (IL)-6 (1.94 ± 0.02 pg/mL vs. 2.17 ± 0.04 pg/mL, P < 0.01), IL-17 (2.16 ± 0.02 pg/mL vs. 2.22 ± 0.002 pg/mL, P < 0.05), and interferon gamma (IFN-γ) (2.07 ± 0.02 pg/mL vs. 2.15 ± 0.04 pg/mL, P < 0.05)) in DS.Conclusions:DS can be explored as a novel inducer of IR in in vitro studies with further standardization, substituting the conventionally used pharmacological factors. Our findings also affirm the validity of ADMSC-CM as a prospective insulin sensitizer for T2DM therapy.
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简介:摘要:STEM教育强调科学、技术、工程、数学的有机融合,加强我国STEM教育能有效地增强学生跨学科思维能力、独立解决复杂问题的能力。STEM课程整合是实现STEM教育的前提基础。但当前我国STEM课程整合情况并不乐观,分析当前我国中小学STEM课程整合中存在的问题,借鉴美国课程整合的经验,得到以下启发:国家加强政策引领,发动社会各界积极参与STEM教育;设置相应的STEM课程标准;重视技术、工程在STEM课程整合中的作用;坚持项目学习、问题解决为导向,促进STEM课程深度整合。
简介:AbstractChronic obstructive pulmonary disease (COPD), characterized by persistent and not fully reversible airflow restrictions, is currently one of the most widespread chronic lung diseases in the world. The most common symptoms of COPD are cough, expectoration, and exertional dyspnea. Although various strategies have been developed during the last few decades, current medical treatment for COPD only focuses on the relief of symptoms, and the reversal of lung function deterioration and improvement in patient’s quality of life are very limited. Consequently, development of novel effective therapeutic strategies for COPD is urgently needed. Stem cells were known to differentiate into a variety of cell types and used to regenerate lung parenchyma and airway structures. Stem cell therapy is a promising therapeutic strategy that has the potential to restore the lung function and improve the quality of life in patients with COPD. This review summarizes the current state of knowledge regarding the clinical research on the treatment of COPD with mesenchymal stem cells (MSCs) and aims to update the understanding of the role of MSCs in COPD treatment, which may be helpful for developing effective therapeutic strategies in clinical settings.
简介:AbstractBackground:Circular RNA (circRNA) is a type of closed circular noncoding RNA (ncRNA), mostly formed by back-splicing or alternative splicing of pre-messenger RNA (mRNA). The aim of this study was to explore the expression profile of circRNA in peripheral blood mononuclear cells (PBMCs) of patients with ankylosing spondylitis (AS) and discover potential molecular markers of AS.Methods:The circRNA microarray technology was used to detect the expression of circRNAs in the peripheral blood of 6 patients with AS and 6 healthy controls (HC). To screen the differentially expressed circRNAs by fold change (FC) and P value, these differentially expressed circRNAs were analyzed by bioinformatics. In 60 cases of AS and 30 cases of HC, 4 circRNAs were subjected to real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), and their correlation with various clinical indicators was analyzed. Finally, the receiver operating characteristic (ROC) curve was used to analyze their potential as AS diagnostic markers.Results:The microarray results showed that there were 1369 significantly differently expressed (P < 0.05, FC > 1.5) circRNAs between the AS and HC groups (675 upregulated and 694 downregulated). The results of bioinformatics analysis suggested that they were mainly involved in "enzyme binding," "adenosine ribonucleotide binding," "MAPK signaling pathway" , etc. The RT-qPCR results showed that the expressions of hsa_circRNA_001544 (U = 486.5, P < 0.05) and hsa_circRNA_102532 (U = 645, P < 0.05) were significantly different between the AS group and the HC group. The AS group was further divided into two subgroups: active AS (ASA) and stable AS (ASS). After analysis, it was found that compared with the HC group, hsa_circRNA_001544 was significantly increased in both ASA (U = 214, P < 0.05) and ASS groups (U = 273, P < 0.05), while hsa_circRNA_008961 (U = 250, P < 0.05) and hsa_circRNA_102532 (U = 295, P < 0.05) were only significantly increased in the ASA group. Furthermore, hsa_circRNA_012732 was significantly different between the ASA and ASS groups (U = 194, P < 0.05), and there was no statistical significance among the remaining groups. Correlation analysis results showed that hsa_circRNA_012732 was negatively correlated with Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), high-sensitivity C-reactive protein (hsCRP), and globulin (GLOB) and positively correlated with lymphocyte count (LY), mean corpusular volume, and albumin (ALB), and hsa_circRNA_008961 was negatively correlated with platelet (PLT) count. ROC curve analysis showed that hsa_circRNA_001544 (95% CI = 0.610-0.831, P < 0.05) and hsa_circRNA_102532 (95% CI = 0.521-0.762, P < 0.05) were statistically significant, and their area under curve (AUC) values were 0.720 and 0.642, respectively.Conclusions:There are differentially expressed circRNAs in PBMCs of AS patients, and they may be involved in the occurrence and development of AS. Among these differentially expressed circRNAs, hsa_circRNA_012732 has the potential to become an indicator of disease activity, and hsa_circRNA_001544 has the potential to become a molecular marker for AS diagnosis.
简介:AbstractBackground:Autophagy of alveolar macrophages is a crucial process in ischemia/reperfusion injury-induced acute lung injury (ALI). Bone marrow-derived mesenchymal stem cells (BM-MSCs) are multipotent cells with the potential for repairing injured sites and regulating autophagy. This study was to investigate the influence of BM-MSCs on autophagy of macrophages in the oxygen-glucose deprivation/restoration (OGD/R) microenvironment and to explore the potential mechanism.Methods:We established a co-culture system of macrophages (RAW264.7) with BM-MSCs under OGD/R conditions in vitro. RAW264.7 cells were transfected with recombinant adenovirus (Ad-mCherry-GFP-LC3B) and autophagic status of RAW264.7 cells was observed under a fluorescence microscope. Autophagy-related proteins light chain 3 (LC3)-I, LC3-II, and p62 in RAW264.7 cells were detected by Western blotting. We used microarray expression analysis to identify the differently expressed genes between OGD/R treated macrophages and macrophages co-culture with BM-MSCs. We investigated the gene heme oxygenase-1 (HO-1), which is downstream of the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway.Results:The ratio of LC3-II/LC3-I of OGD/R treated RAW264.7 cells was increased (1.27 ± 0.20 vs. 0.44 ± 0.08, t = 6.67, P < 0.05), while the expression of p62 was decreased (0.77 ± 0.04 vs. 0.95 ± 0.10, t = 2.90, P < 0.05), and PI3K (0.40 ± 0.06 vs. 0.63 ± 0.10, t = 3.42, P < 0.05) and p-Akt/Akt ratio was also decreased (0.39 ± 0.02 vs. 0.58 ± 0.03, t = 9.13, P < 0.05). BM-MSCs reduced the LC3-II/LC3-I ratio of OGD/R treated RAW264.7 cells (0.68 ± 0.14 vs. 1.27 ± 0.20, t = 4.12, P < 0.05), up-regulated p62 expression (1.10 ± 0.20 vs. 0.77 ± 0.04, t = 2.80, P < 0.05), and up-regulated PI3K (0.54 ± 0.05 vs. 0.40 ± 0.06, t = 3.11, P < 0.05) and p-Akt/Akt ratios (0.52 ± 0.05 vs. 0.39 ± 0.02, t = 9.13, P < 0.05). A whole-genome microarray assay screened the differentially expressed gene HO-1, which is downstream of the PI3K/Akt signaling pathway, and the alteration of HO-1 mRNA and protein expression was consistent with the data on PI3K/Akt pathway.Conclusions:Our results suggest the existence of the PI3K/Akt/HO-1 signaling pathway in RAW264.7 cells under OGD/R circumstances in vitro, revealing the mechanism underlying BM-MSC-mediated regulation of autophagy and enriching the understanding of potential therapeutic targets for the treatment of ALI.