RSC Advances
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2017
·Vol. 7
·期 20
·12185-12193
·
IF 3.108
Yuhua Zhang,Keming Jiang,Degang Qing,Bing Huang,Jiayi Jiang,Shumei Wang,Chunyan Yan
Camptotheca acuminata Decne (Nyssaceae) is a major natural source of the anticancer drug camptothecin (CPT) and its derivatives. The leaves and stems are two of the main regions that accumulate CPT in C. acuminata. In this study, we successfully isolated cambial meristematic cells (CMCs) and dedifferentiated cells (DDCs) from C. acuminata stems and leaves, identified their characteristic features using micrograph analysis, and assessed their hypersensitivity to γ-irradiation and zeocin. The growth and kinetics curves of CMCs and DDCs were also studied. Furthermore, the accumulation of CPT and 10-hydroxycamptothecin (HCPT)—a more potent and less toxic CPT derivative—was assessed by liquid chromatography, and the transcriptional levels of nine genes encoding key enzymes involved in CPT and HCPT biosynthesis was assessed using quantitative real-time polymerase chain reaction (PCR) in CMCs and DDCs. The results showed that CMCs induced were particularly hypersensitive to γ-irradiation and zeocin and presented with abundant and small vacuoles, whereas DDCs were not. The above morphological and physiological characteristics of CMCs were consistent with previous reports. B5 medium was determined as the best growth medium for CMCs and DDCs. The accumulation of CPT and HCPT was higher in CMCs than DDCs, and the expression of IPI, G10H, ASA1, TSB, TDC1, TDC2, and STR was significantly upregulated in CMCs compared with DDCs; HMGR2 and HMGR3 were downregulated in CMCs. We speculate that the high accumulation of CPT and HCPT in CMCs was due to the upregulation of these seven genes.
研究领域:
药理学
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植物生物学
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分子生物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR MEDICINE-JMM
·
2023
·
IF 4.7
Chen Yinghui,Wu Yizhuo,Feng Weiqi,Luo Xueyang,Xiao Bing,Ding Xiaowei,Gu Yongjia,Lu Yanan,Yu Yu
Abstract The ductus arteriosus (DA), bridging the aorta and pulmonary artery, immediately starts closing after birth. Remodeling of DA leads to anatomic obstruction to prevent repatency. Several histological changes, especially extracellular matrices (ECMs) deposition and smooth muscle cells (SMCs) migration bring to anatomic closure. The genetic etiology and mechanism of DA closure remain elusive. We have previously reported a novel copy number variant containing Vav2 in patent ductus arteriosus (PDA) patients, but its specific role in DA closure remains unknown. The present study revealed that the expression of Vav2 was reduced in human patent DA, and it was less enrichment in the adjacent aorta. Matrigel experiments demonstrated that Vav2 could promote SMC migration from PDA patient explants. Smooth muscle cells with Vav2 overexpression also presented an increased capacity in migration and downregulated contractile-related proteins. Meanwhile, SMCs with Vav2 overexpression exhibited higher expression of collagen III and lessened protein abundance of lysyl oxidase, and both changes are beneficial to DA remodeling. Overexpression of Vav2 resulted in increased activity of Rac1, Cdc42, and RhoA in SMCs. Further investigation noteworthily found that the above alterations caused by Vav2 overexpression were particularly reversed by Rac1 inhibitor. A heterozygous, rare Vav2 variant was identified in PDA patients. Compared with the wild type, this variant attenuated Vav2 protein expression and weakened the activation of downstream Rac1, further impairing its functions in SMCs. In conclusion, Vav2 functions as an activator for Rac1 in SMCs to promote SMCs migration, dedifferentiation, and ECMs production. Deleterious variant potentially induces Vav2 loss of function, further providing possible molecular mechanisms about Vav2 in PDA pathogenesis. These findings enriched the current genetic etiology of PDA, which may provide a novel target for prenatal diagnosis and treatment. Key messages
Although we have proposed the potential association between Vav2 and PDA incidence through whole exome sequencing, the molecular mechanisms underlying Vav2 in PDA have never been reported. This work, for the first time, demonstrated that Vav2 was exclusively expressed in closed DAs.
Moreover, we found that Vav2 participated in the process of anatomic closure by mediating SMCs migration, dedifferentiation, and ECMs deposition through Rac1 activation.
Our findings first identified a deleterious Vav2 c.701C>T variant that affected its function in SMCs by impairing Rac1 activation, which may lead to PDA defect. Vav2 may become an early diagnosis and an effective intervention target for PDA clinical therapy.
研究领域:
心血管生物学
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遗传学
·
分子生物学
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发育生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2024
·
IF 6.1
Yang Liu,Xiaoting Chen,Xueqin Tan,Yeqian Huang,Wen Zhang,Zhicun Wang,Li Yang,Yunbing Wang,Zhengyong Li,Xingdong Zhang
Microtia profoundly affects patients' appearance and psychological well-being. Tissue engineering ear cartilage scaffolds have emerged as the most promising solution for ear reconstruction. However, constructing tissue engineering ear cartilage scaffolds requires multiple passaging of chondrocytes, resulting in their dedifferentiation and lose their special phenotypes and functions. To tackle these issues, here we employ guanidinobenzoic acid (GBA) modified Generation 5 Polyamidoamine (PAMAM) dendrimers (PG) as Runx1 plasmid carrier to construct PG/pRunx1 polyplex nanoparticles. The PG/pRunx1 polyplexes are transfected into human auricular chondrocytes, significantly mitigating chondrocyte dedifferentiation and enhancing cartilage regeneration during the in vitro culture. Furthermore, we develop a highly porous double-network hydrogels based on methacrylate-functionalized and oxidized chondroitin sulfate and carbohydrazide-modified gelatin and the hydrogels possessed both dynamic adaptability and mechanical support characteristics by reversible dynamic covalent crosslinking and static covalent crosslinking, serving as an ideal scaffold for tissue engineering. Consequently, chondrocytes treated with PG/pRunx1 polyplex nanoparticles are incorporated into the hydrogels to construct tissue-engineered auricular cartilage scaffolds. After subcutaneous implantation in nude mice, the scaffolds containing chondrocytes treated with PG/pRunx1 nanoparticles showed more mature cartilaginous tissue, characterized by prominent ECM deposition and enhanced chondrogenesis. Therefore, this research provides a novel strategy for the development of tissue-engineered auricular cartilage scaffolds.
研究领域:
组织工程
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再生医学
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生物材料
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生物医学工程
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细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOTECHNOLOGY LETTERS
·
2024
·
IF 2
Yao Yongchang,Chen Ke,Pan Qian,Gao Hui,Su Weixian,Zheng Shicong,Dong Weiqiang,Qian Dongyang
Objectives We genetically modified dedifferentiated chondrocytes (DCs) using lentiviral vectors and adenoviral vectors encoding TGF-β3 (referred to as transgenic groups below) and encapsulated these DCs in the microcavitary hydrogel and investigated the combinational effect on redifferentiation of the genetically manipulated DCs. Results The Cell Counting Kit-8 data indicated that both transgenic groups exhibited significantly higher cell viability in the first week but inferior cell viability in the subsequent timepoints compared with those of the control group. Real-time polymerase chain reaction and western blot analysis results demonstrated that both transgenic groups had a better effect on redifferentiation to some extent, as evidenced by higher expression levels of chondrogenic genes, suggesting the validity of combination with transgenic DCs and the microcavitary hydrogel on redifferentiation. Although transgenic DCs with adenoviral vectors presented a superior extent of redifferentiation, they also expressed greater levels of the hypertrophic gene type X collagen. It is still worth further exploring how to deliver TGF-β3 more efficiently and optimizing the appropriate parameters, including concentration and duration. Conclusions The results demonstrated the better redifferentiation effect of DCs with the combinational use of transgenic TGF-β3 and a microcavitary alginate hydrogel and implied that DCs would be alternative seed cells for cartilage tissue engineering due to their easily achieved sufficient cell amounts through multiple passages and great potential to redifferentiate to produce cartilaginous extracellular matrix.
研究领域:
生物医学工程
·
组织工程
·
细胞生物学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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