阿伐他汀激活wnt/β-catenin信号通路促进骨质疏松模型大鼠移植物的骨整合

doi:10.3969/j.issn.2095-4344.2016.20.008

中国组织工程研究 ›› 2016, Vol. 20 ›› Issue (20): 2940-2948.doi: 10.3969/j.issn.2095-4344.2016.20.008

• 骨组织构建 bone tissue construction • 上一篇下一篇

阿伐他汀激活wnt/β-catenin信号通路促进骨质疏松模型大鼠移植物的骨整合

梁耀中1，陈舒2，杨裕豪1，蓝春海1，张国威1，纪志盛1，林宏生1

暨南大学附属第一医院，1骨科，2妇产科，广东省广州市 510630

收稿日期:2016-04-06 出版日期:2016-05-13 发布日期:2016-05-13
通讯作者: 林宏生，博士，教授，主任医师。暨南大学附属第一医院骨科，广东省广州市 510630
作者简介:梁耀中，男，1980年生，广西壮族自治区人，汉族，2010年暨南大学毕业，硕士，主治医师，主要从事脊柱外科及关节外科与骨组织工程研究。
基金资助:
广东省自然科学基金(2014A030313357)

Atorvastatin promotes implant
osseointegration via the activation of
Wnt/β-catenin signal pathway in osteoporotic rats

Liang Yao-zhong1, Chen Shu2, Yang Yu-hao1, Lan Chun-hai1, Zhang Guo-wei1, Ji Zhi-sheng1,
Lin Hong-sheng1

1 Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, Guangdong Province, China
2 Department of Gynaecology and Obstetrics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, Guangdong Province, China

Received:2016-04-06 Online:2016-05-13 Published:2016-05-13
Contact: Lin Hong-sheng, M.D., Chief physician, Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, Guangdong Province, China
About author:Liang Yao-zhong, Master, Attending physician, Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, Guangdong Province, China
Supported by:
the Natural Science Foundation of Guangdong Province, China, No. 2014A030313357

摘要/Abstract

摘要：

文章快速阅读：

文题释义：
骨质疏松症：是多种原因引起的一组骨病，骨组织有正常的钙化，钙盐与基质呈正常比例，以单位体积内骨组织量减少为特点的代谢性骨病变。在多数骨质疏松中，骨组织的减少主要由于骨质吸收增多所致，以骨骼疼痛、易于骨折为特征。
骨结合：为正常的改建骨和种植体直接接触，无光学显微镜下可见到的软组织长入，并能使种植体的负荷持续传导并分散在骨组织中。

摘要
背景：最近研究报道阿伐他汀可减少骨流失和骨折，但其对移植物骨整合的影响尚未可知。
目的：探讨阿伐他汀在骨质疏松症动物模型中对移植性骨整合的作用及相关作用机制。
方法：将48只SD大鼠随机分为假手术组，卵巢切除组，10，20 mg/(kg•d)阿伐他汀治疗组。除假手术组外，其他各组均进行卵巢切除手术和骨移植。干预12周后检测各组大鼠椎骨骨密度，移植物骨整合率及移植物抗拔强度。另外，用阿伐他汀处理大鼠的成骨细胞，酶联免疫法检测细胞中骨形成及骨吸收生物指标的表达情况，RT-PCR检测wnt信号通路相关基因的mRNA表达水平。
结果与结论：20 mg/(kg•d)阿伐他汀治疗组大鼠的骨密度、骨整合率及移植物抗拔强度均明显高于卵巢切除组(P < 0.05)。用阿伐他汀处理的大鼠成骨细胞中碱性磷酸酶、骨钙蛋白及骨保护素表达水平明显升高(P < 0.05)，破骨细胞分化因子核因子κB受体活化因子配体的表达显著降低(P < 0.05)。阿伐他汀治疗组明显提高低密度脂蛋白相关蛋白5和连环蛋白的mRNA表达(P < 0.05)，抑制Wnt信号通路抑制剂DKK1和骨硬化蛋白Sost的表达(P < 0.05)。结果证实，阿伐他汀可通过上调Wnt/β-catenin信号通路，促进骨质疏松模型大鼠移植物的骨整合。

中国组织工程研究杂志出版内容重点：组织构建；骨细胞；软骨细胞；细胞培养；成纤维细胞；血管内皮细胞；骨质疏松；组织工程
ORCID: 0000-0002-3641-6505(Lin Hong-sheng)

关键词: 组织构建, 骨组织工程, 阿伐他汀, 卵巢切除术, 移植性骨整合, 骨质疏松症, 高血脂症, 碱性磷酸酶, 骨保护素, 骨钙蛋白, 破骨分化因子, Wnt信号通路, 广东省自然科学基金

Abstract:

BACKGROUND: Atorvastatin has been shown to reduce bone loss and fracture, but its effects on implant osseointegration remain unknown.
OBJECTIVE: To investigate the effects of atorvastatin on implant osseointegration in osteoporotic rats and the underlying mechanisms.
METHODS: Forty-eight Sprague-Dawley rats were randomized into sham-surgery, ovariectomy, and atorvastatin (10 and 20 mg/kg per day) treatment groups, respectively. All rats received ovariectomy and implant surgery except those in the sham-surgery group. Bone mineral density of the lumbar vertebra, osseointegration ratio and pull-out strength of implants were measured after 12-week treatment. Levels of bone formation and resorption markers in osteoblasts treated with atorvastatin were determined by ELISA. Wnt pathway-related gene expression was detected by RT-PCR.
RESULTS AND CONCLUSION: Bone mineral density, osseointegration ratio and pull-out strength of implants were significantly increased in 20 mg/kg per day of atorvastatin treatment group compared with ovariectomy group (P < 0.05). Levels of alkaline phosphatase, osteocalcin and osteoprotegerin were significantly increased in osteoblasts treated with atorvastatin in vitro (P < 0 .05), and the level of osteoclast differentiation factor RANKL was significantly inhibited (P < 0.05). Meanwhile, atorvastatin significantly promoted the mRNA expression of low-density lipoprotein associated protein 5 and β-catenin, and inhibited the mRNA expression of dickkopf Wnt signal pathway inhibitor 1 and sclerostin. Our results suggest that atorvastatin promotes implant osseointegration in osteoporotic rats by activating Wnt/β-catenin signal pathway.

中国组织工程研究杂志出版内容重点：组织构建；骨细胞；软骨细胞；细胞培养；成纤维细胞；血管内皮细胞；骨质疏松；组织工程

Key words: Osteoporosis, Ovariectomy, Bone Transplantation, Osseointegration, Tissue Engineering

中图分类号:

R318

梁耀中1，陈舒2，杨裕豪1，蓝春海1，张国威1，纪志盛1，林宏生1. 阿伐他汀激活wnt/β-catenin信号通路促进骨质疏松模型大鼠移植物的骨整合[J]. 中国组织工程研究, 2016, 20(20): 2940-2948.

Liang Yao-zhong1, Chen Shu2, Yang Yu-hao1, Lan Chun-hai1, Zhang Guo-wei1, Ji Zhi-sheng1, . Atorvastatin promotes implant
osseointegration via the activation of
Wnt/β-catenin signal pathway in osteoporotic rats[J]. Chinese Journal of Tissue Engineering Research, 2016, 20(20): 2940-2948.

图/表（结果） 3

Effect of atorvastatin on BMD of osteoporotic rats

BMD of L₄ vertebrae in the Sham, ovariectomy, AST 10 and AST 20 groups at different time points are showed in Table 2. BMD of rats receiving ovariectomy was decreased. BMD of rats in AST 20 group was significantly increased compared with AST 10 group (P < 0.05). There was no significant difference in BMD between AST 20 and Sham groups (P > 0.05).

Effect of atorvastatin on histomorphometry and OIS ratio of implants in osteoporotic rats

Bone mass around the implant and OIS were obviously decreased in the VOX group compared with those in the Sham group, while it was markedly increased after atorvastatin administration, especially in AST 20 group, the bone mass was similar to that in the Sham group (Figure 1A). Moreover, the administration of atorvastatin signficantly increased OIS compared with the OVX group (P < 0.05). More bone mass around the implant and higher OIS were observed in the OVX 20 group compared with the OVX group (P < 0.05), while no significant differences were found between the AST 20 and sham-surgery groups (Figure 1B).

Effect of atorvastatin on the push-out strength of the tibias in osteoporotic rats

As presented in Figure 2, it was found that the maximum push-out force of the tibias in the OVX group was signi?cantly decreased compared with that of the Sham group (P < 0.05). Oral administration of atorvastatin (AST 10 and AST 20) signi?cantly increased the maximum push-out force of the tibias

(P < 0.05). Moreover, higher dosage of AST showed more pronounced effect on the increase of maximum push-out force of the tibias (P < 0.05). No difference was found between the Sham and AST 20 groups

(P > 0.05).

Effect of atorvastatin on bone formation markers in osteoblasts

As displayed in Figure 3A, the ALP activity in the AST group was significantly increased compared with that in the control group on day 7 (P < 0.05). Further increase in the ALP activity in both groups was observed on day 14, especially in the AST group. It was also found that the OCN concentration was significantly increased in the AST group compared with the control group (P < 0.05), and the OCN concentration in both groups were increased with time (Figure 3B).

Effect of atorvastatin on bone resorption markers in osteoblasts

It was found that the OPG level in AST group was significantly increased compared with that in control group after 7- and 14-day of cell culture (Figure 4A). However, the RANKL concentration was significantly decreased in the osteoblasts treated with atorvastatin for 7 or 14 days (Figure 4B). The ratio between OPG and RANKL also increased with time in the AST group (Figure 4C).

Effect of atorvastatin on mRNA expression of the Wnt signaling pathway

mRNA expression of the Wnt signaling pathway including DKK1, Sost, LRP5, and β-catenin were detected by RT-PCR, and the results were presented in Figure 5. Atorvastatin treatment significantly decreased the mRNA expression of DKK-1 to 0.5-fold (P < 0.05), Sost to 0.4-fold (P < 0.05), respectively; and significantly increased LRP5 up to 3.5-fold (P < 0.05), β-catenin to 4.5-fold (P < 0.05), compared with those of the control group, suggesting atorvastatin activates the Wnt signaling pathway.

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引言

As the most common bone diseases, osteoporosis and osteoporotic fractures affect millions of people globally and lead to high morbidity and high expenditure^[1]. In North America, there are approximately 1.5 million cases of osteoporotic fractures per year, with the mortality rate of approximately 20%^[2]. Osteoporosis would adversely affect the osseointegration of bone implants in the elderly population, by decreasing implant instant stability and increasing risks of implant loosening, shifting, and subsidence during the long-term follow-up. To date, there is no preferable solution to address this problem mentioned above, although some medical therapies for prevention or slowing down of bone loss rather than enhancing bone formation are now available in the clinic. To enhance bone formation in osseointegration issue, recent studies made promising progress. Interestingly, atorvastatin (3-hydroxy-3- methylglutaryl

coenzyme A reductase inhibitors, HMG-CoA), a traditional hypolipidemic agent, has been recently confirmed to be effective as a bone anabolic agent. In the past years, atorvastatin has been shown to play pleiotropic effects by modulating the immune system^{[3- 4]}, atherosclerotic plaque stability^[5], angiogenesis^[6], endothelial recruitment^[7], and neuroprotection^[8]. Recently, statins have been shown to be associated with increased bone mineral density (BMD)^[9] and a reduced fracture risk^[10-13]. Moreover, statins are believed to increase the bone mass by enhancing bone morphogenetic protein-2-mediated osteoblast expression, suggesting that atorvastatin may protect against osteoporosis^[14-17]. In addition, Gradosova et al.^[18]reported that atorvastatin had a beneficial effect on bone metabolism by improving BMD and bone biomechanical properties. However, a negative association between statin use and BMD increase and bone repair was detected in a previous study^[19].

Until now, whether atorvastatin shows positive effects on osteoporosis remains unclear. Additionally, the effects of atorvastatin on implant osseointegration and the underlying mechanisms remain poorly understood. Therefore, in the present study, a rat model of osteoporosis was established by bilateral ovariectomy, and the tibia was implanted. The effects of atorvastatin on implant osseointegration in osteoporotic rats were investigated. In addition, rat osteoblasts were cultured, and the effects of atorvastatin on osteoblasts were evaluated by detecting the bone formation and resorption markers in vitro. The mechanism of action of atorvastatin was also explored.

中国组织工程研究杂志出版内容重点：组织构建；骨细胞；软骨细胞；细胞培养；成纤维细胞；血管内皮细胞；骨质疏松；组织工程

材料方法

MATERIALS AND METHODS

Design

An observational experiment.

Time and setting

Experiments were performed at the Laboratory of Chigang campus of Guangdong College of Pharmacy Building between February 2014 and August 2015.

Materials

Forty-eight Sprague-Dawley female rats, aged 5 months and weighing (280±25) g, were provided by the Animal Center of Southern Medical University, Guangzhou, China (license No. SCXK (Yue) 2013-0020). Rats were kept in polypropylene cages under a 12 hour light/dark cycle at (25±1) ℃ and were allowed free access to food and water. The protocol was approved by the Animal Ethics Committee of Jinan University, China.

Methods

Surgical procedure

All rats were randomized into sham-surgery (Sham), ovariectomy (OVX), AST 10, and AST 20 groups, respectively. Bone mineral density (BMD) of the fourth lumbar vertebra (L₄) was measured by dual-energy X-ray absorptiometry (DEXA, Discovery, Histologic, USA). Rats in ovariectomy and both atorvastatin treatment groups received bilateral ovariectomy followed by tibia implant after 8 weeks, while rats in the sham-surgery group only received sham operation. Rats in the AST 10, and AST 20 groups were orally administrated 10 and 20 mg/kg per day of atorvastatin for 12 consecutive weeks, respectively, and rats in the sham and OVX groups were given saline. The doses of atorvastatin were given based on earlier safety and efficacy animal studies, and those were similar to the results from the study of the influence of atorvastatin on bone metabolism in rodents assessed by other researchers. At the end of the study, the rats were euthanized with an overdose of thiopental, and the tibias and femurs were harvested for further study.

A rat osteoporotic model was established by bilateral ovariectomy according to the method described previously^[20]. Briefly, the rats were anesthetized with 10% chloral hydrate (280-350 mg/kg, i.p.), and then a peritoneal incision was made to expose the uterine tube, and both ovaries were removed and the abdominal wall was surgically closed. The sham procedure was performed in the same manner without the removal of the ovaries. BMD of the L₄ vertebrae in rats was determined after 8 weeks. The average declines of BMD beyond 20% were defined as the successful osteoporosis model. After osteoporosis models were established, the rats received bone implant to repair bone defect in the tibia. In brief, an incision was made through the skin and periosteumn in the rats, and then a certain size of tibia with posterior tibial artery was amputated and transplanted to the limb of osteoporotic rats. Finally, bone sections were fixed with screws.

Push-out strength test

For push-out test, tibias from rats in each group were removed after 12 weeks and pull-out test was performed according to a protocol described previously^[20]. In brief, the tibia was placed in the cavity mold, and the proximal end (2 mm) of the implant was exposed. And then polymethylmethacrylate was used again to embed the tibia. The quadrate moulds with tibiae were then ?xed on a material testing system (MTS858 bionixII machine, MTS System Inc., Minneapolis, MN, USA). Compression loads were applied vertically to the proximal end of the implant at a speed of 5 mm/min, and maximum push out force was recorded at 100 Hz.

Histomorphometric analysis

For histomorphometric analysis, the tibias from each rat were removed after 12 weeks and fixed for 24 hours, and then embedded in methylmethacrylate, sectioned at 5 mm. Histomorphometric analysis was performed by an experienced technician blinded to the treatment of rats. To quantify the osseointegration ratio, the index of the osseointegrated implant surface (OIS), which was defined as the ratio (%) of the implant surface directly contacted with surrounding bone to total implant surface, was determined. Three slices were taken from each sample. Calculated by the computer, the average OIS of the three slices were considered as the OIS of that sample. Image J1.31p software was used to analyze the pictures caught by a microscope (National Institutes of Health, Bethesda, MD, USA) and automatically calculate the circumference of the prosthesis and percentage of bone attachment to the prosthesis.

Cell culture

Rat skulls (10 g) from OVX group were carefully dissected, cut into small fragments, and washed in phosphate-buffer solution (PBS) to remove non-adherent cells, and then placed in T75 flask. The bone fragments were incubated in phenol red-free minimal essential medium (MEM) (Gibco, Gran Island, NY, USA) supplemented with 10% FBS (1 mmol/L), penicillin (56 U/mL), and streptomycin (56 U/mL), until confluence. Cells at passage 3 were seeded at density of 10,000/mL into 6-well plate and fed with or without atorvastatin (20 nmol/L). Cell cultures were collected and analyzed on days 7 and 14 until they reached confluence.

ELISA assay

After osteoblasts were cultured for 7 and 14 days, the typical bone formation markers, including alkaline phosphatase (ALP) activity, osteocalcin (OCN), and bone resorption markers including osteoprotegerin (OPG), RANKL were detected by enzyme-linked immunosorbent assay using ELISA assay kits (Life technology, USA) on microplate reader, according to the manufacturer's instructions.

RT-PCR

Total RNA of cells was extracted using the TriPure Isolation Reagent (Invitrogen Corp.), and then RNA was quantified by ultra violet (UV)-spectrometry (Thermo Scientific). Total RNA (1 μg) was reversely transcribed into cDNA with the Transcriptor First Strand cDNA Synthesis Kit (Roche Applied Science). PCR amplification was performed using a Light Cycler Instrument and the Light Cycler Fast Start DNA Master SYBR Green 1 Kit (Roche Applied Science) according to the manufacturer’s instructions. The differences in the threshold cycles for glyceraldehyde-3-phosphate dehydrogenase (GAPDH), dickkopf Wnt signaling pathway inhibitor (DKK1), sclerostin (Sost), low-density lipoprotein associated protein 5LRP5, β-catenin were used to calculate the mRNA expressions. GAPDH was used as reference gene, and the expression ratios were obtained using the comparative cycle threshold method (2^-??Ct). The primers for DKK1, Sost, LRP5, β-catenin and GAPDH are listed in Table 1.

Table 1 Primer sequences for RT-qPCR

Gene	Sequence (5’-3’)	Product size (bp)
DKK1	Forward: ATG AGG CAC GCT ATG TGC TG Reverse: CTC GAG GTA AAT GGC TGT GGT C	82
Sost	Forward: GAG TAC CCA GAG CCT CCT CA Reverse: AGC ACA CCA ACT CGG TGA	193
LRP5	Forward: GCT CCT GCA GAA CCT GCT GA Reverse: CAC CAG TGG CAC ATG CAA AC	74
β-Catenin	Forward: GTC TGA GGA CAA GCC ACA GGA CTA C Reverse: AAT GTC CAG TCC GAG ATC AGC A	115
GAPDH	Forward: AGA CAG CCG CAT CTT CTT GT Reverse: CTT GCC GTG GGT AGA GTC AT	207

Note: DKK1: Dickkopf Wnt signaling pathway inhibitor 1; Sost: sclerostin; LRP5: low-density lipoprotein associated protein 5; GAPDH: glyceraldehyde-3-phosphate dehydrogenase;

Statistical analysis

Data were analyzed using SPSS 13.0 statistical software (SPSS, Chicago, IL, USA). The measurement data were experssed as the mean± SD. Intergroup comparisons were analyzed using one-way analysis of variance. A value of P < 0.05 was considered statistically significant.

讨论

Osteoporosis is defined as a systemic skeletal impairment characterized by low bone mass, the deterioration of bone tissues and an increased risk of fracture^[21-22]. Recently, atorvastatin is reported to reduce bone loss and fracture, but its effect on implant fixation is still unknown. Therefore, the present study aimed to investigate the effect of atorvastatin on the implant fixation, and elucidate the underlying mechanisms. The OVX animal model has been widely used for the evaluation of potential osteoporosis treatment^[23-24]. In the present study, the rat osteoporosis models established by bilateral ovariectomy received implant surgery to repair bone defect in the tibia. BMD, histomorphometry, OIS ratio and push-out strength of tibias were evaluated. The results confirmed that the osteoporotic rats administrated with therapeutic doses of atorvastatin had a significant increase in BMD. Moreover, it was found that therapeutic doses of atorvastatin obviously enhanced implant osteointegration including bone-implant contact ratio and osseointergrated implant surface (OIS) in a dose-dependent manner.

In order to investigate the effects of atorvastatin on the growth of osteoblasts, the bone formation markers of ALP and OCN and bone resorption markers of OPG and RANKL were measured in the present study. ALP was found to be an osteoblast marker for bone mineralization. OCN was a non-collagenous protein secreted by osteoblasts, which plays a role in mineralization and calcium ion homeostasis. RANKL was a member of the tumor necrosis factor (TNF) cytokine family, which regulates osteoclast differentiation and activation. OPG was a decoy receptor for RANKL which works by neutralizing its function in osteoclastogenesis through inhibiting the activation of osteoclasts and promoting osteoclast apoptosis^[25]. The results of the present study showed that atorvastatin increased the bone marker of ALP, OCN, OPG, OPG/RANKL, and reduced RANKL, which indicated that atorvastatin can enhance osteoblastic differentiation and inhibit bone resorption.

In 1999, Mundy et al.^[26] first observed that statins possessed positive effects on osteoblasts by enhancing bone morphogenetic protein-2 expression which enhanced osteogenesis. Subsequently, some studies showed that statins exert osteogenic effects by inhibiting the formation of osteoclasts and controlling bone resorption^[27-31], which is consistent with the findings of Mundy et al. Osteopenia and osteoporosis shared the same receptor activator of NF-kB Ligand/osteoprotegerin (RANKL/OPG) pathway^[32-33], which provide molecular evidence for the anti-osteoporotic effect of atorvastatin. Some studies focused on the underlying mechanisms involving the mevalonic acid (MVA) pathway^[34-35] and RANKL/OPG pathway involved in the mediation process^[36-37], which play a role in the lipid modulation as well as the bone metabolism pathway. In the present study, we found that the positive effects of therapeutic doses of atorvastatin on bone mass and implant osseointegration in osteoporotic animal models. More importantly, we confirmed that the beneficial effects of atorvastatin treatment on bone mass and osseointegration were realized by increasing the concentrations of ALP, OCN and the ratio of OPG/RANKL, which accelerated osteoblastic differentiation and inhibited osteoclastic formation.

Until recently, the effects of statins on bone mass and BMD in vivo remain controversial. Some studies demonstrated the positive effects of atorvastatin on the increase of BMD in animal models^[38], but others found a negative association between statins and the increase in BMD and bone repair^[19]. The present study confirmed that the positive effects of oral administration with therapeutic doses of atorvastatin on BMD in animal models. Additionally, We are the first to show that atorvastatin obviously enhances bone-implant contact ratio, OIS and even push-out strength of the tibias in a dose-dependent manner in vivo.

Up to now, the mechanism by which atorvastatin enhances osteoblastic differentiation was not fully understood. Recently, Wnt signaling pathway has caught attentions as a potential target for osteoporosis treatment due to its important role in bone development^[39]. Wnt/β-catenin pathway is a highly complex and unique signaling pathway, which has ability to regulate gene expression, cell invasion, migration, proliferation, and differentiation for the initiation and progression of bone metastasis^[40-41]. DKK-1 and Sost were the two important Wnt pathway inhibitors. The inhibition of DKK-1 expression has been reported to link to high bone mass while overexpression of DKK-1 results in osteopenia in mice^[42-43]. Sost, a glycoprotein-secreted predominantly by osteocytes, is one antagonist of Wnt signaling that has been implicated in the process of bone formation by binding to the LRP5/6 receptor^[44]. Deletion of the Sost gene increased bone formation in mice while overexpression of Sost leads to significant bone loss^[45-46]. LRP5, a known low-density receptor-related protein, plays an essential role in cellular proliferation and osteoblastogenesis via the β-catenin signaling pathway^{[25, 47]}. In the present study, we found atorvastatin enhanced the mRNA expressions of Wnt membrane receptors (LRP5) and the downstream gene (β-catenin) of Wnt signal pathway, and significantly inhibited the mRNA expressions of DKK1 and Sost. These findings suggest that the mechanism by which atorvastatin promotes the implant fixation and osteoblastic differentiation involves the wnt/β-catenin signal pathway activated by atorvastatin.

However, our study has several limitations. First, we did not assess direct or indirect effects of atorvastatin on osteoclast functions. Second, we did not assess other osteoblastic factors that have been reported to be regulated by statins, including BMP-2, aggrecan and type 2 collagen, vascular endothelial growth factor, and metalloproteinase-9. However, the present study is the first to confirm the positive effect of oral administration of atorvastatin on implant osseointegration. Additionally, we confirmed that the desirable effects of atorvastatin were executed through bone cell biology approachs.

In conclusion, atorvastatin can enhance implant osteointegration in osteoporotic rats by promoting the bone formation and inhibiting bone resorption via activating Wnt/β-catenin signal pathway, which provide strong and valuable scientific evidence for clinical application of atorvastatin, especially for the patients with osteoporotic fracture.

中国组织工程研究杂志出版内容重点：组织构建；骨细胞；软骨细胞；细胞培养；成纤维细胞；血管内皮细胞；骨质疏松；组织工程

阿伐他汀激活wnt/β-catenin信号通路促进骨质疏松模型大鼠移植物的骨整合

Atorvastatin promotes implant
osseointegration via the activation of
Wnt/β-catenin signal pathway in osteoporotic rats

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阿伐他汀激活wnt/β-catenin信号通路促进骨质疏松模型大鼠移植物的骨整合

Atorvastatin promotes implant osseointegration via the activation of Wnt/β-catenin signal pathway in osteoporotic rats

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Atorvastatin promotes implant
osseointegration via the activation of
Wnt/β-catenin signal pathway in osteoporotic rats