Department of Chemical Engineering and Pharmaceutical Technology, Universidad de La Laguna, La Laguna, 38206, Spain.
Institute of Biomedical Technologies (ITB), Universidad de La Laguna, La Laguna, 38320, Spain.
Int J Nanomedicine. 2024 Nov 20;19:12171-12188. doi: 10.2147/IJN.S476546. eCollection 2024.
Osteoporosis is a metabolic disorder characterized by the loss of bone mass and density. Nucleic acid-based therapies are among the most innovative approaches for osteoporosis management, although their effective delivery to bone tissue remains a challenge. In this work, SFRP1-silencing GampeR loaded-nanoparticles were prepared and functionalized with specific moieties to improve bone targeting and, consequently, therapeutic efficacy. SFRP1-silencing would promote osteoblastic differentiation by enhancing the WNT/β-catenin pathway and thus diminishing the progression of osteoporosis.
A nucleic acid-based delivery system consisting of lipid-polymer hybrid nanoparticles (LPNPs) loading a GapmeR for SFRP1 silencing was developed and further functionalized with two bone-targeting moieties: a specific aptamer (Apt) for murine mesenchymal stem cells and an antiresorptive drug, namely alendronate (ALD). These systems were tested in vivo in osteoporotic mice at different dosage regimens to analyze dose dependence in bone-forming activity and potential toxicity. The quality of trabecular and cortical bone was assessed by both micro computed tomography (micro-CT) and histological and histomorphometric analyses. Early and late osteogenesis were quantified by immunohistochemistry.
Results showed that functionalizing LPNPs loaded with an SFRP1-silencing GapmeR using both Apt and ALD improved bone quality and enhanced osteogenesis following a dose-effect relationship, as revealed by micro-CT, histological and immunohistochemical analyses. In contrast, non-functionalized LPNPs did not produce these effects.
These findings highlight the relevance of proper targeting and dosage in nucleic acid-based therapeutics, proving to be crucial for exerting their therapeutic effect: a deficient targeting strategy and/or dosage may result in the therapeutic failure of an adequate gene therapy agent.
骨质疏松症是一种代谢性疾病，其特征是骨量和密度的丧失。核酸疗法是骨质疏松症管理中最具创新性的方法之一，尽管它们向骨组织的有效传递仍然是一个挑战。在这项工作中，制备了沉默 SFRP1 的 GampeR 负载纳米颗粒，并对其进行了功能化修饰，以改善骨靶向性，从而提高治疗效果。沉默 SFRP1 可通过增强 WNT/β-catenin 通路促进成骨细胞分化，从而减缓骨质疏松症的进展。
开发了一种由脂质-聚合物杂化纳米颗粒（LPNP）负载用于 SFRP1 沉默的 GapmeR 的核酸递药系统，并进一步用两种骨靶向部分进行功能化：一种用于鼠间充质干细胞的特异性适配体（Apt）和一种抗吸收药物，即阿仑膦酸钠（ALD）。这些系统在不同剂量方案的骨质疏松症小鼠体内进行了测试，以分析成骨活性和潜在毒性的剂量依赖性。通过微计算机断层扫描（micro-CT）以及组织学和组织形态计量学分析评估了小梁骨和皮质骨的质量。通过免疫组织化学定量评估早期和晚期成骨。
结果表明，用 Apt 和 ALD 对负载沉默 SFRP1 的 GapmeR 的 LPNP 进行功能化，改善了骨质量，并增强了成骨作用，呈剂量效应关系，这通过 micro-CT、组织学和免疫组织化学分析得到证实。相比之下，未功能化的 LPNP 没有产生这些效果。
这些发现强调了适当的靶向和剂量在核酸治疗中的重要性，证明这对于发挥其治疗效果至关重要：靶向策略和/或剂量不足可能导致适当的基因治疗剂治疗失败。
