英语科研杂志（读外刊科学学英语）

本文节选自2021年12月8日发表在《科学》（SCIENCE ADVANCES Vol 7, Issue 50）的论文，Advanced PLGA hybrid scaffold with a bioactive PDRN/BMP2 nanocomplex for angiogenesis and bone regeneration using human fetal MSCs——具有生物活性的基于PDRN/BMP2纳米复合物的先进PLGA混合支架，利用人胎儿MSCs进行血管生成和骨再生。

Advanced PLGA hybrid scaffold with a bioactive PDRN/BMP2 nanocomplex for angiogenesis and bone regeneration using human fetal MSCs

具有生物活性的基于PDRN/BMP2纳米复合物的先进PLGA混合支架，利用人胎儿MSCs进行血管生成和骨再生

Biodegradable polymers have been used with various systems for tissue engineering.

生物可降解聚合物已用于各种组织工程系统。

Among them, poly(lactic-co-glycolic) acid (PLGA) has been widely used as a biomaterial for bone regeneration because of its great biocompatibility and biodegradability properties.

其中，聚乳酸-羟基乙酸（PLGA）具有良好的生物相容性和生物降解性，已被广泛用作骨再生的生物材料。

However, there remain substantial cruxes that the by-products of PLGA result in an acidic environment at the implanting site, and the polymer has a weak mechanical property.

然而，PLGA的副产物会导致植入部位的酸性环境，以及聚合物的力学性能较弱等问题仍然存在。

In our previous study, magnesium hydroxide (MH) and bone extracellular matrix are combined with a PLGA scaffold (PME) to improve anti-inflammation and mechanical properties and osteoconductivity.

在我们之前的研究中，氢氧化镁（MH）和骨细胞外基质与PLGA支架（PME）结合，以提高抗炎、力学性能和骨传导性。

In the present study, the development of a bioactive nanocomplex (NC) formed along with polydeoxyribonucleotide and bone morphogenetic protein 2 (BMP2) provides synergistic abilities in angiogenesis and bone regeneration.

在本研究中，由多脱氧核糖核酸核苷酸和骨形态发生蛋白2 (BMP2)组成的生物活性纳米复合物(NC)在血管生成和骨再生方面提供了协同能力。

This PME hybrid scaffold immobilized with NC (PME/NC) achieves outstanding performance in anti-inflammation, angiogenesis, and osteogenesis.

这种用NC固定的PME混合支架（PME/NC）在抗炎、血管生成和成骨方面具有优异的性能。

Such an advanced PME/NC scaffold suggests an integrated bone graft substitute for bone regeneration.

这种先进的PME/NC支架暗示了一种完整的骨移植替代物，用于骨再生。

重点词汇

mechanical property 力学性质；机械性能

magnesium hydroxide 氢氧化镁

extracellular matrix 胞外基质

combined with 与…结合 ; 联合

mechanical properties 机械性能；力学性质

along with 随着 ; 除某物以外 ; 随同…一起，跟…一起

With the design of a functionalized polymer-based scaffold for effective bone repair, many studies have emerged using prospective techniques such as bioactive molecule immobilization.

随着功能化聚合物基支架的设计用于有效的骨修复，许多研究使用了前瞻性的技术，如生物活性分子固定化。

However, it was said that bioactive molecules immobilized on the polymeric scaffold should have proper delivery systems because of several limitations, including rapid clearance, poor physiological stability, nonspecific targeting, and low permeability into the target tissue.

然而，有人说，固定在聚合物支架上的生物活性分子应具有适当的输送系统，因为存在一些限制，包括快速清除、较差的生理稳定性、非特异性靶向性和对靶组织的低渗透性。

To solve these problems, we proposed a self-assembled nanocomplex (NC) immobilization system.

为了解决这些问题，我们提出了一种自组装纳米复合物（NC）固定化系统。

The novel bioactive NC, which contains two different effective molecules, positively charged bone morphogenetic protein 2 (BMP2) and negatively charged polydeoxyribonucleotide (PDRN), can exert synergistic effects on bone regeneration.

新型生物活性NC含有两种不同的有效分子，带正电的骨形态发生蛋白2（BMP2）和带负电的聚脱氧核糖核酸（PDRN），可对骨再生产生协同效应。

Here, the NC spontaneously sinks on the surface of the scaffold in calcium- and phosphate-rich environment by ionic interaction.

在此，NC在富钙、富磷酸盐的环境中通过离子相互作用在支架表面自发下沉。

By introducing natural physical phenomenon, these bioactive molecules can be effectively immobilized on the surface and induced controlled release.

通过引入自然物理现象，将这些生物活性分子有效地固定在表面，诱导可控释放。

重点词汇

low permeability 低透水性

positively charged 带正电荷的

negatively charged 带负电荷的

on the surface of 上面

Recent studies have suggested that angiogenesis performs an important role in bone regeneration.

最近的研究表明，血管生成在骨再生中起着重要作用。

To address this issue, PDRN would be a considerable molecule, which enhances angiogenic effect during bone formation. Baek et al. reported that PDRN has a brilliant ability for angiogenesis and plays as an agonist of adenosine A2A receptor.

为了解决这个问题，PDRN将是一个重要的分子，它可以增强骨形成过程中的血管生成作用。Baek等报道PDRN具有出色的血管生成能力，并作为腺苷A2A受体的激动剂发挥作用。

Consequently, it accelerates the down-regulation of acute inflammation and up-regulates angiogenic factors, such as vascular endothelial growth factor (VEGF). PDRN is considered as an appropriate bioactive molecule for successfully regenerating a vascularized bone tissue.

因此，它加速急性炎症的下调，并上调血管生成因子，如血管内皮生长因子（VEGF）。PDRN被认为是成功再生血管化骨组织的合适生物活性分子。

Meanwhile, bone morphogenetic proteins are predominant molecules that play an important role in many bone regeneration studies. Among them, BMP2 is estimated to be the most promising molecule for bone regeneration.

同时，骨形态发生蛋白是在许多骨再生研究中起重要作用的主要分子。其中，BMP2被认为是最有希望的骨再生分子。

Although it has a great ability for bone repair, treatment with high dose of BMP2 has led to numerous side effects, such as cancer development, cytotoxicity, ectopic bone formation, and renal problems. In many other studies, the BMP2 was incorporated in various scaffolds for bone regeneration.

尽管BMP2具有很强的骨修复能力，但高剂量BMP2治疗已导致许多副作用，如癌症发展、细胞毒性、异位骨形成和肾脏问题。在许多其他研究中，BMP2被纳入各种骨再生支架中。

Walsh et al. and Liu et al. used 5 μg per scaffold and 400 ng per scaffold, respectively, whereas our PME/NC [PME hybrid scaffold immobilized with NC] scaffold has only 200 ng of recombinant human BMP2 per scaffold.

Walsh 等人和Liu 等人分别使用5μg/支架和400 ng/支架，而我们的PME/NC[PME混合支架用NC固定]支架每个支架只有200 ng重组人BMP2。

In other words, BMP2 has side effects when used a lot; so, it is good to use as little as to achieve its effect, as in our scaffolds.

换句话说，BMP2在大量使用时有副作用；所以，在我们的支架中，尽可能少地使用以达到其效果是很好的。

The efficiency of NC immobilization to the scaffold can increase in supersaturated calcium-phosphate solution (Ca/P = 1.67). We hypothesize that this novel bioactive NC has a dual effect on angiogenesis and osteogenesis.

在过饱和磷酸钙溶液（Ca/P=1.67）中，NC固定在支架上的效率可以提高。我们假设这种新的生物活性NC对血管生成和成骨具有双重作用。

重点词汇

bone formation 骨形成；骨生成

ability for 在…方面的能力

acute inflammation 急性炎症

be the most 是最好的

Moreover, mesenchymal stem cells (MSCs) are of great therapeutic potential for a variety of diseases because of their ability to self-renew and differentiate into multiple tissues.

此外，间充质干细胞(mesenchymal stem cells, MSCs)具有自我更新和分化为多种组织的能力，对多种疾病有很大的治疗潜力。

Among them, human fetal-derived MSCs (hfMSCs) correspond to the time of birth of human bone and show superior potential to osteogenic differentiation compared to adult MSCs (e.g., human bone marrow MSCs, human umbilical cord MSCs).

其中，人胎儿来源的骨髓间充质干细胞（hfMSCs）与人骨的出生时间相对应，与成人骨髓间充质干细胞（如人骨髓间充质干细胞、人脐带间充质干细胞）相比，显示出更高的成骨分化潜能。

It also displays great osteogenesis and lower immunogenicity, as compared to MSC from perinatal and postnatal sources.

与围产期和产后来源的间充质干细胞相比，它还显示出巨大的成骨能力和较低的免疫原性。

hfMSCs were seeded on an NC-immobilized hybrid scaffold to enhance bone regenerative efficacy.

将hfMSCs植入NC固定的混合支架以增强骨再生效果。

In this study, an advanced PLGA/mMH/bECM hybrid scaffold with NC (PME/NC) was prepared, and the great capacity for biocompatibility, inhibition of osteoclast differentiation, and osteogenic ability of hfMSCs was investigated in vitro.

本研究制备了一种先进的PLGA/mMH/bECM复合NC支架(PME/NC)，并在体外研究了hfMSCs的生物相容性、抑制破骨细胞分化和成骨能力。

In addition, to evaluate the reduced inflammation response and angiogenic effect as well as bone regenerative efficacies of the PME/NC in vivo, 8 weeks of implantation into critical-size rat calvarial defect was performed and compared with other scaffolds.

此外，为了评估PME/NC在体内降低的炎症反应、血管生成效果以及骨再生效果，我们将PME/NC植入大鼠颅骨缺损8周，并与其他支架进行比较。

重点词汇

a variety of 各种各样的 ; 种种 ; 形形色色

differentiate into 区分为

correspond to 相当于

compared to 与…相比 ; 比拟

bone marrow 骨髓

umbilical cord 脐带

In summary, the advanced bone regeneration system using the PME/NC scaffold has multifunctional ability that plays a crucial role as a substantial bone graft biomaterial.

综上所述，采用PME/NC支架的先进骨再生系统具有多功能，作为一种实质性的骨移植生物材料发挥着至关重要的作用。

The existing PME scaffold showed significantly improved mechanical properties and a pH-neutralizing capacity.

现有的PME支架显著改善了力学性能和ph中和能力。

The NC was successfully immobilized on the scaffold for the controlled release of bioactive molecules, BMP2 and PDRN.

成功将NC固定在支架上，实现生物活性分子BMP2和PDRN的控释。

As shown in the in vitro results, the PME/NC scaffold has many magnificent properties that increase its regenerative effects, which are biocompatibility, osteoclast inhibition, and osteogenesis.

体外实验结果表明，PME/NC支架具有生物相容性、破骨细胞抑制和成骨等多种显著的特性，可提高其再生效果。

Moreover, the PME/NC with hfMSCs performed outstanding bone tissue repair in critical-sized rat calvarial defects because of its surpassing potential of osteogenic differentiation.

此外，含hfMSCs的PME/NC对大鼠颅骨缺损进行了出色的骨组织修复，因为其成骨分化的潜力超过了预期。

In addition, the PME/NC exhibited interesting effects on angiogenesis as well as anti-inflammatory and antibacterial responses around the defected area.

此外，PME/NC在缺陷区域周围的血管生成以及抗炎和抗菌反应中表现出有趣的作用。

In particular, neovascularization with the PME/NC scaffold was improved as much as that of the native group in vivo.

特别是，使用PME/NC支架的新生血管的改善程度与在体原生组相同。

In the field of bone tissue engineering, many other approaches have been attempted for effective bone regeneration via several side abilities such as neovascularization and antibacterial effect.

在骨组织工程领域，通过血管再生和抗菌作用等多种辅助功能，已经尝试了许多其他方法来实现有效的骨再生。

The advanced PME/NC hybrid scaffold showed great multifunctional effects: osteogenesis, anti-inflammation, angiogenesis, and antibacterial effect.

新型PME/NC复合支架具有成骨、抗炎、血管生成和抗菌等多种功能。

On the basis of these results, we suggest that the advanced PME/NC hybrid scaffold be developed using differentiated approaches from previous studies to achieve various applications in bone regeneration.

基于这些结果，我们建议使用与先前研究不同的方法开发先进的PME/NC混合支架，以实现骨再生中的各种应用。

It would be a highly effective therapeutic strategy in bone tissue engineering and regenerative medicine.

这将是骨组织工程和再生医学中一种高效的治疗策略。

重点词汇

controlled release 控制释放的

bone tissue 骨组织

In addition 此外 ; 另外;加之;除…之外

as well as 以及 ; 既…又… ; 除…之外 ; 此外

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