Alendronate nanoparticles promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway

Background: Fracture is a common skeletal disorder, and fracture healing is a complex biological process. The Wingless-Int-Integrated/beta-catenin (Wnt/β-catenin) signaling pathway plays an important role in bone formation and fracture healing. Low-density lipoprotein receptor-related protein 4 (LRP...

Full description

Saved in:
Bibliographic Details
Main Authors: ZW Sun, QL Zhu, JP Gong, YH Sui, XY Liu
Format: Article
Language:English
Published: Forum Multimedia Publishing LLC 2025-06-01
Series:European Cells & Materials
Subjects:
Online Access:https://www.ecmjournal.org/papers/vol051/vol051a06.php
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850110429292920832
author ZW Sun
QL Zhu
JP Gong
YH Sui
XY Liu
author_facet ZW Sun
QL Zhu
JP Gong
YH Sui
XY Liu
author_sort ZW Sun
collection DOAJ
description Background: Fracture is a common skeletal disorder, and fracture healing is a complex biological process. The Wingless-Int-Integrated/beta-catenin (Wnt/β-catenin) signaling pathway plays an important role in bone formation and fracture healing. Low-density lipoprotein receptor-related protein 4 (LRP4) has been reported to negatively regulate the Wnt/β-catenin pathway. This study investigated whether alendronate nanoparticles (alendronate-NPs) can activate the Wnt/β-catenin pathway by inhibiting LRP4, thereby promoting fracture healing. Methods: We initially synthesized alendronate-NPs. Then, the impact of alendronate, alendronate-NPs, and LRP4 on the osteogenic differentiation of rat osteoblasts was investigated. The proliferation capacity of osteoblasts was evaluated using cell-counting kit-8. The effects on the messenger ribonucleic acid (mRNA) and protein levels of proliferating cell nuclear antigen (PCNA), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), osteopontin (OPN), LRP4, Wingless-type MMTV integration site family, member 4 (Wnt4), glycogen synthase kinase 3 beta (GSK-3β), p-GSK-3β, and β-catenin were analyzed by quantitative reverse-transcription polymerase chain reaction and Western blot. The impact on osteoblast apoptosis and calcium deposition was assessed using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and alizarin red staining assays. A rat fracture model was then established, followed by treatments with either alendronate or alendronate-NPs. Bone formation during fracture healing was evaluated using alkaline phosphatase. The effects of alendronate and alendronate-NPs on fracture healing were assessed through hematoxylin-eosin (HE) staining and immunohistochemistry staining of collagen I. Results: Alendronate and alendronate-NPs significantly downregulated the expression of LRP4 during osteoblast differentiation and upregulated the expression of downstream targets of the Wnt/β-catenin pathway (p < 0.01). The co-treatment of osteoblasts with alendronate-NPs and LRP4 overexpression partially offset the bone-formation-promoting effects of alendronate-NPs. LRP4 overexpression reversed the proliferative and osteogenic effects of alendronate-NPs (p < 0.01). Compared with alendronate-NP treatment alone, the combined treatment of alendronate-NPs and LRP4 overexpression downregulated the expression of downstream targets of the Wnt/β-catenin pathway in osteoblasts (p < 0.01). Alendronate and alendronate-NPs significantly accelerated fracture healing in rats. They also promoted the proliferation and bone-formation capacity of osteoblasts, with alendronate-NPs showing a more pronounced therapeutic effect on fracture healing than alendronate. Conclusions: Alendronate-NPs may promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway. This study provides experimental evidence for a new mechanism of alendronate-NPs in promoting fracture healing.
format Article
id doaj-art-c32c0008efe14698bb0e3b04bb8f19e0
institution OA Journals
issn 1473-2262
language English
publishDate 2025-06-01
publisher Forum Multimedia Publishing LLC
record_format Article
series European Cells & Materials
spelling doaj-art-c32c0008efe14698bb0e3b04bb8f19e02025-08-20T02:37:50ZengForum Multimedia Publishing LLCEuropean Cells & Materials1473-22622025-06-015110311910.22203/eCM.v051a06Alendronate nanoparticles promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathwayZW SunQL ZhuJP GongYH SuiXY LiuBackground: Fracture is a common skeletal disorder, and fracture healing is a complex biological process. The Wingless-Int-Integrated/beta-catenin (Wnt/β-catenin) signaling pathway plays an important role in bone formation and fracture healing. Low-density lipoprotein receptor-related protein 4 (LRP4) has been reported to negatively regulate the Wnt/β-catenin pathway. This study investigated whether alendronate nanoparticles (alendronate-NPs) can activate the Wnt/β-catenin pathway by inhibiting LRP4, thereby promoting fracture healing. Methods: We initially synthesized alendronate-NPs. Then, the impact of alendronate, alendronate-NPs, and LRP4 on the osteogenic differentiation of rat osteoblasts was investigated. The proliferation capacity of osteoblasts was evaluated using cell-counting kit-8. The effects on the messenger ribonucleic acid (mRNA) and protein levels of proliferating cell nuclear antigen (PCNA), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), osteopontin (OPN), LRP4, Wingless-type MMTV integration site family, member 4 (Wnt4), glycogen synthase kinase 3 beta (GSK-3β), p-GSK-3β, and β-catenin were analyzed by quantitative reverse-transcription polymerase chain reaction and Western blot. The impact on osteoblast apoptosis and calcium deposition was assessed using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and alizarin red staining assays. A rat fracture model was then established, followed by treatments with either alendronate or alendronate-NPs. Bone formation during fracture healing was evaluated using alkaline phosphatase. The effects of alendronate and alendronate-NPs on fracture healing were assessed through hematoxylin-eosin (HE) staining and immunohistochemistry staining of collagen I. Results: Alendronate and alendronate-NPs significantly downregulated the expression of LRP4 during osteoblast differentiation and upregulated the expression of downstream targets of the Wnt/β-catenin pathway (p < 0.01). The co-treatment of osteoblasts with alendronate-NPs and LRP4 overexpression partially offset the bone-formation-promoting effects of alendronate-NPs. LRP4 overexpression reversed the proliferative and osteogenic effects of alendronate-NPs (p < 0.01). Compared with alendronate-NP treatment alone, the combined treatment of alendronate-NPs and LRP4 overexpression downregulated the expression of downstream targets of the Wnt/β-catenin pathway in osteoblasts (p < 0.01). Alendronate and alendronate-NPs significantly accelerated fracture healing in rats. They also promoted the proliferation and bone-formation capacity of osteoblasts, with alendronate-NPs showing a more pronounced therapeutic effect on fracture healing than alendronate. Conclusions: Alendronate-NPs may promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway. This study provides experimental evidence for a new mechanism of alendronate-NPs in promoting fracture healing.https://www.ecmjournal.org/papers/vol051/vol051a06.phpalendronate nanoparticleslrp4wnt/β-catenin pathwaybone-fracture healing
spellingShingle ZW Sun
QL Zhu
JP Gong
YH Sui
XY Liu
Alendronate nanoparticles promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway
European Cells & Materials
alendronate nanoparticles
lrp4
wnt/β-catenin pathway
bone-fracture healing
title Alendronate nanoparticles promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway
title_full Alendronate nanoparticles promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway
title_fullStr Alendronate nanoparticles promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway
title_full_unstemmed Alendronate nanoparticles promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway
title_short Alendronate nanoparticles promote fracture healing by inhibiting LRP4 to activate the Wnt/β-catenin pathway
title_sort alendronate nanoparticles promote fracture healing by inhibiting lrp4 to activate the wnt β catenin pathway
topic alendronate nanoparticles
lrp4
wnt/β-catenin pathway
bone-fracture healing
url https://www.ecmjournal.org/papers/vol051/vol051a06.php
work_keys_str_mv AT zwsun alendronatenanoparticlespromotefracturehealingbyinhibitinglrp4toactivatethewntbcateninpathway
AT qlzhu alendronatenanoparticlespromotefracturehealingbyinhibitinglrp4toactivatethewntbcateninpathway
AT jpgong alendronatenanoparticlespromotefracturehealingbyinhibitinglrp4toactivatethewntbcateninpathway
AT yhsui alendronatenanoparticlespromotefracturehealingbyinhibitinglrp4toactivatethewntbcateninpathway
AT xyliu alendronatenanoparticlespromotefracturehealingbyinhibitinglrp4toactivatethewntbcateninpathway