纳米技术在骨质疏松症治疗中的研究进展

目的 总结纳米技术在骨质疏松症治疗中的研究进展,展望其在临床上的应用前景。方法 应用计算机检索Pubmed、中国期刊全文数据库(CNKI)中2006-2023年的相关文献。在标题、摘要、关键词中以“nano, osteoporosis, bone marrow mesenchymal stem cells(BMMSCs),treatment”或“纳米,骨质疏松,骨髓间充质干细胞,治疗”为检索词进行检索。选择与纳米技术治疗骨质疏松症密切相关的文章,优先选择时间最近且发表于权威杂志的文章。结果 对筛选到的文献进行精选得到34篇文献进行综述。结论 纳米技术由于其高靶向性、高利用率和低不良反应的特性,在骨质疏松症的治疗研究中备受关注。目前常用的纳米技术包括药物纳米化和纳米载药两大类。但目前纳米技术尚未在临床上应用于骨质疏松症的治疗,仍有许多问题待解决。

纳米技术方法学概述及其改善中药抗肿瘤单体药性的研究

在中医药理论的指导下,中药在抑制肿瘤增殖、转移等方面发挥了重要的作用。由于中药复方的成分复杂,在对中药成分的深入研究中,中药单体抗肿瘤的作用越来越受到人们的重视。因其水溶性较差、生物利用度较低等诸多问题,严重限制了药物研发和在临床中的应用。纳米技术在改善中药单体溶解性、生物利用度等方面具有广阔的应用前景。系统阐述了纳米技术的分类及制备方法,探讨了纳米技术改善中药单体药性及其抗肿瘤作用,分析其发展中面临的问题,并对研究方向进行了展望。

Hollow iron oxide nanoparticles as multidrug resistant drug delivery and imaging vehicles

Magnetic nanopartides have been used as drug delivery vehicles against a number of cancer cells. Most of these theranostic formulations have used solid iron oxide nanoparticles （SIONPs） loaded with chemotherapeutics as nano-carrier formulation for both magnetic resonance imaging （MRI） and cancer therapy. In this study, we applied the dopamine-plus-human serum albumin （HSA） method to modify hollow iron oxide nanoparticles （HIONPs） and encapsuated doxorubicin （DOX） within the hollow porous structure of the nano-carrier. The new delivery system can load more drug than solid iron oxide nanoparticles of the same core size using the same coating strategy. The HIONPs-DOX formulation also has a pH-dependent drug release behaviour. Compared with free DOX, the HIONPs-DOX were more effectively uptaken by the multidrug resistant OVCAR8- ADR cells and consequently more potent in killing drug resistant cancer cells. MRI phantom and cell studies also showed that the HIONPs-DOX can decrease the T2 MRI signal intensity and can be used as a MR/contrast agent while acting as a drug delivery vehicle. For the first time, the dual application of chemo drug transport and MR imaging using the HIONPs-DOX formulation was achieved against both DOX-sensitive and DOX-resistant cancer cells.

Hollow mesoporous Ia3d silica nanospheres with single- unit-cell-thick shell： Spontaneous formation and drug delivery application

Mesoporous silica nanoparticles （MSNs） are promising for drug delivery and other biomedical applications owing to their excellent chemical stability and biocompatibility. For these applications, a hollow morphology with thin shell and open mesopores is preferred for MSNs in order to maximize the loading capacity of drugs. Herein we report a novel and direct synthesis of such an ideal drug delivery system in a dilute and alkaline solution of benzylcetyl- dimethylammonium chloride and diethylene glycol hexadecyl ether. The mixed surfactants can guide the formation of MSNs with cubic Ia3d mesostructure, and at a concentration of sodium hydroxide between 9.8 and 13.5 mM, hollow MSNs with uniform sizes of 90-120 nm and a single-unit-cell-thick shell are formed. A mechanism for the formation of the hollow Ia3d MSNs, designated as MMT-2, is proposed based on in situ small-angle X-ray scattering measurements and other analyses. MMT-2 exhibits much higher loading capacity of ibuprofen and degrades faster in simulated body fluid and phosphate buffered saline than non-hollow MSNs. The degradation of MMT-2 can be significantly retarded by modification with polyethylene glycol. More interestingly, the degradation of MMT-2 involves fragmentation instead of void formation, a phenomenon beneficial for their elimination. The results demonstrate the uniqueness of the hollow Ia3d MSNs and the great potential of the material for drug delivery and biomedical applications.

Au nanostructures:an emerging prospect in cancer theranostics

Au nanoparticles have been used in biomedical applications since ancient times. However, the rapid development of nanotechnology over the past century has led to recognition of the great potential of Au nanoparticles in a wide range of applications. Advanced fabrication techniques allow us to synthesize a variety of Au nanostructures possessing physiochemical properties that can be exploited for different purposes. Functionalization of the surface of Au nanoparticles further eases their application in various roles. These advantages of Au nanoparticles make them particularly suited for cancer treatment and diagnosis. The small size of Au particles enables them to preferentially accumulate at tumor sites to achieve in vivo targeting after systemic administration. Efficient light absorption followed by rapid heat conversion makes them very promising in photothermal therapy. The facile surface chemistry of Au nanoparticles eases delivery of drugs, ligands or imaging contrast agents in vivo. In this review, we summarize recent development of Au nanoparticles in cancer theranostics including imaging-based detection, photothermal therapy, chemical therapy and drug delivery. The multifunctional nature of Au nanoparticles means they hold great promise as novel anti-cancer therapeutics.

A novel bone marrow targeted gadofullerene agent protect against oxidative injury in chemotherapy

Chemotherapy as an effective cancer treatment technique has been widely used in tumor therapy. However, it is still a challenge to overcome the serious side effects of chemotherapy, especially for its myelotoxicity. Here we report a novel strategy using the water soluble gadofullerene nanocrystals（GFNCs） to protect against chemotherapy injury in hepatocarcinoma bearing mice, which was induced by the commonly chemotherapeutic agent cyclophosphamide（CTX）.The GFNCs were revealed to specifically accumulate in the bone marrow after intravenously injecting to mice and they exhibited excellent radical scavenging function, resulting in a prominent increase of mice blood cells and pathological improvements of the primary organs in the GFNCs（15 mg kg-（-1））treated mice after the CTX（60 mg kg-（-1）） therapy. Moreover,the GFNCs maintained and even strengthened the antineoplastic activity of the CTX agent. Therefore, the GFNCs would be the promising chemoprotective agents in chemotherapy based on their high efficiency, low toxicity and metabolizable property.