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71.
Ju Zhou Qing Lan Wu Li Lin Yang Jing You Yan‐Mei Zhang Wei Ni 《Cell biology international》2020,44(1):108-116
To investigate the roles of tripartite motif containing 52 (TRIM52) in human hepatic fibrosis in vitro, human hepatic stellate cell line LX‐2 cells were transfected with hepatitis B virus (HBV) replicon to establish HBV‐induced fibrosis in LX‐2 cells, and then treated with small interfering RNA‐mediated knockdown of TRIM52 (siTRIM52). LX‐2 cells without HBV replicon transfection were treated with lentiviruses‐mediated overexpression of TRIM52 and phosphatase magnesium dependent 1A (PPM1A). Fibrosis response of LX‐2 cells were assessed by the production of hydroxyproline (Hyp) and collagen I/III, as well as protein levels of α‐smooth muscle actin (α‐SMA). PPM1A and phosphorylated (p)‐Smad2/3 were measured to assess the mechanism. The correlation between TRIM52 and PPM1A was determined using co‐immunoprecipitation, and whether and how TRIM52 regulated the degradation of PPM1A were determined by ubiquitination assay. Our data confirmed HBV‐induced fibrogenesis of LX‐2 cells, as evidenced by significant increase in Hyp and collagen I/III and α‐SMA, which was associated with reduction of PPM1A and elevation of transforming growth factor‐β (TGF‐β), p‐Smad2/3, and p‐Smad3L. However, those changes induced by HBV were significantly attenuated with additional siTRIM52 treatment. Similar to HBV, overexpression of TRIM52 exerted promoted effect in the fibrosis of LX‐2 cells. Interestingly, TRIM52 induced the fibrogenesis of LX‐2 cells and the activation of TGF‐β/Smad pathway were significantly reversed by PPM1A overexpression. Furthermore, our data confirmed TRIM52 as a deubiquitinase that influenced the accumulation of PPM1A protein, and subsequently regulated the fibrogenesis of LX‐2 cells. TRIM52 was a fibrosis promoter in hepatic fibrosis in vitro, likely through PPM1A‐mediated TGF‐β/Smad pathway. 相似文献
72.
Xiao‐Li Li Fei Yu Bao‐Ying Li Chun‐Li Fu Xin Yu Mei Xu Mei Cheng Hai‐Qing Gao 《Cell biology international》2020,44(1):268-277
The progression of diabetic cardiomyopathy is related to cardiomyocyte dysfunction and apoptosis. Our previous studies showed that asporin (ASPN) was significantly increased in the myocardium of db/db mice through proteomics, and grape seed procyanidin B2 (GSPB2) significantly inhibited the expression of ASPN in the heart of db/db mice. We report here that ASPN played a critical role in glycated low‐density lipoproteins (gly‐LDL) induced‐cardiomyocyte apoptosis. We found that gly‐LDL upregulated ASPN expression. ASPN increased H9C2 cardiomyocyte apoptosis with down‐regulation of Bcl‐2, upregulation of transforming growth factor‐β1, Bax, collagen III, fibronectin, and phosphorylation of smad2 and smad3. However, GSPB2 treatment reversed ASPN‐induced impairments in H9C2 cardiomyocytes. These results provide evidence for the cardioprotective action of GSPB2 against ASPN injury, and thus suggest a new target for fighting against diabetic cardiomyopathy. 相似文献
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74.
Tripartite motif protein 25 (TRIM25) expression was altered in various human cancers. Herein, we found that the expression of TRIM25 was elevated in hepatocellular carcinoma (HCC) tissues and cell lines. Knockdown of TRIM25 increased the sensitivity of HCC HepG2 cells to epirubicin (EPI), as indicated by reduced cell viability, enhanced cell apoptosis, and downregulated P‐glycoprotein (P‐gp) and multiple drug‐resistance protein 1 (MRP1). Moreover, TRIM25 knockdown strengthened the effects of EPI on phosphatase and tensin homolog (PTEN) and phosphorylated (p)‐AKT. However, overexpression of TRIM25 exerted an opposite effect, weakening the sensitivity of Huh7 to EPI, and obviously increasing PTEN and reducing p‐AKT. Most important, all the changes induced by TRIM25 overexpression in Huh7 were reversed with additional treatment of LY294002 (an AKT pathway inhibitor). Notably, coimmunoprecipitation experiments confirmed the interaction between TRIM25 and PTEN. Knockdown of TRIM25 resulted in reduced ubiquitination of PTEN protein. Collectively, our data suggested that TRIM25 enhanced EPI resistance via modulating PTEN/AKT pathway, and targeting TRIM25 may enhance the sensitivity of HCC cells toward chemotherapy drugs. 相似文献
75.
AbstractThe purpose of the study was to acquire the source and evaluate the risk posed by heavy metals in road dust of steel industrial city (Anshan), Liaoning, Northeast China. Potential ecological risk index (RI), pollution index (PI) and geo-accumulation index (Igeo) were applied to evaluate the heavy metal pollution level, and the carcinogenic risk (RI) and hazard index (HI) were calculated to estimate the human health risk. The geographic information system maps clearly reveal the hot spots of heavy metal spatial distribution. Principle component analysis (PCA) and cluster analysis (CA) classified heavy metals into three groups. The metal Zn and Pb originate from the traffic emission, while Cd, Cr, Fe, Mn, Ni and Sb primarily come from industrial activities. These two pathways were the major source of heavy metals pollution by positive matrix factorization (PMF). The Igeo and PI values of heavy metals were decreased in the following order: Cd?>?Sb?>?Zn?>?Fe?>?Pb?>?Cu?>?Cr?>?Sn?>?Mn?>?Ni. The RI index showed the heavy metals were moderate to very high potential ecological risk. The HI values for children and adults presented a decreasing order of Cr?>?Pb?>?Ni?>?Cu?>?Cd?>?Zn. The HI also predicted a possibility of non-carcinogenic risk for children living in urban areas in comparison with adults. 相似文献
76.
Zhengyun Zou Qiuxiang Ou Yu Ren Qing Lv Lanqun Qin Lianjun Zhao Shu Su Xue Wu Hua Bao Ao Wang Dongqin Zhu Xiaonan Wang Yang W. Shao Baorui Liu 《Pigment cell & melanoma research》2020,33(4):601-611
The incidence of melanoma is rising globally including China. Comparing to Caucasians, the incidence of non‐cutaneous melanomas is significantly higher in Chinese. Herein, we performed genomic profiling of 89 Chinese surgically resected primary melanomas, including acral (n = 54), cutaneous (n = 22), and mucosal (n = 13), by hybrid capture‐based next‐generation sequencing. We show that mucosal melanomas tended to harbor more pathogenic mutations than other types of melanoma, though the biological significance of this finding remains uncertain. Chromosomal arm‐level alterations including 6q, 9p, and 10p/q loss were highly recurrent in all subtypes, but mucosal melanoma was significantly associated with increased genomic instability. Importantly, 7p gain significantly correlated with unfavorable clinical outcomes in non‐cutaneous melanomas, representing an intriguing prognostic biomarker of those subtypes. Furthermore, focal amplification of 4q12 (KIT, KDR, and PDGFRα) and RAD51 deletion were more abundant in mucosal melanoma, while NOTCH2 amplification was enriched in acral melanoma. Additionally, cutaneous melanomas had higher mutation load than acral melanomas, while mucosal melanomas did not differ from other subtypes in mutation burden. Together, our data revealed important features of acral and mucosal melanomas in Chinese including distinctive driver mutation pattern and increased genomic instability. These findings highlight the possibilities of combination therapies in the clinical management of melanoma. 相似文献
77.
78.
Jingwen Li Xi Long Qing Zhang Xi Fang Na Li Zhicheng Lin Jinghong Li Nian Xiong 《PLoS neglected tropical diseases》2020,14(12)
Medical staff treating Coronavirus Disease 2019 (COVID-19) patients are at high risk for exposure to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), and many have been infected, which may cause panic among medical workers, their relatives, health professionals, and government leaders. We report the epidemiologic and clinical characteristics of healthcare workers and that the majority of infected medical staff had milder symptoms/conditions with a better prognosis than admitted patients. Timely improvement to medical staff’s working conditions such as allowing adequate rest and providing sufficient medical protection is extremely important. 相似文献
79.
80.
Liping Liu Lihua Zhao Piaojuan Chen Hanyang Cai Zhimin Hou Xingyue Jin Mohammad Aslam Mengnan Chai Linyi Lai Qing He Yanhui Liu Xiaoyi Huang Huihuang Chen Yingzhi Chen Yuan Qin 《The Plant journal : for cell and molecular biology》2020,102(6):1172-1186
Angiosperm reproductive development is a complex event that includes floral organ development, male and female gametophyte formation and interaction between the male and female reproductive organs for successful fertilization. Previous studies have revealed the redundant function of ATP binding cassette subfamily G (ABCG) transporters ABCG1 and ABCG16 in pollen development, but whether they are involved in other reproductive processes is unknown. Here we show that ABCG1 and ABCG16 were not only expressed in anthers and stamen filaments but also enriched in pistil tissues, including the stigma, style, transmitting tract and ovule. We further demonstrated that pistil‐expressed ABCG1 and ABCG16 promoted rapid pollen tube growth through their effects on auxin distribution and auxin flow in the pistil. Moreover, disrupted auxin homeostasis in stamen filaments was associated with defective filament elongation. Our work reveals the key functions of ABCG1 and ABCG16 in reproductive development and provides clues for identifying ABCG1 and ABCG16 substrates in Arabidopsis. 相似文献