Lanthanide containing compounds for therapeutic care in bone resorption disorders
作者:Cheri A. Barta、Kristina Sachs-Barrable、Jessica Jia、Katherine H. Thompson、Kishor M. Wasan、Chris Orvig
DOI:10.1039/b705123a
日期:——
Lanthanide ions, Ln(III), are known functional mimics of Ca(II) ions and have been shown to affect the bone remodeling cycle. Exploiting this disruption to the bone remodeling cycle has potential for the treatment of bone density disorders, such as osteoporosis. In an effort to find new orally active agents for these disorders, a series of Ln(III) containing complexes incorporating small, non-toxic, bidentate pyrone and pyridinone ligands have been synthesized and characterized (LnL3, Ln = La, Eu, Gd, Tb, Yb, L = 3-oxy-2-methyl-4-pyrone (ma−), 3-oxy-2-ethyl-4-pyrone (ema−), 3-oxy-1,2-dimethyl-4-pyridinone (dpp−) and 3-oxy-2-methyl-4(1H)-pyridinone (mpp−)). Preliminary biological analysis included cytotoxicity, cell uptake and bidirectional transport studies in Caco-2 cells and in vitro hydroxyapatite (HA) binding studies. The proportion of intact compounds bound to HA was calculated based on determination of Ln(III) concentration by ICP-MS and by UV-vis spectrophotometric assay of the proligand in solution. The LnL3 species were found to have IC50 values at least 6 times greater than that of cisplatin, ≥ 98% HA-binding capacity, and permeability coefficients in the moderate range. La(dpp)3 was ascertained to be the lead compound for the treatment of bone density disorders with the highest percentage cell uptake of 9.07 ± 2.33% and the highest preliminary Papp value of 3.54 ± 2.86 × 10−6 cm s−1 compared to the other LnL3 complexes tested.
镧系离子Ln(III)被认为是钙离子Ca(II)的功能模拟物,并已显示出对骨重塑周期的影响。利用这种对骨重塑周期的干扰有望治疗骨密度疾病,如骨质疏松症。为了寻找这些疾病的新型口服活性剂,合成并表征了一系列含有小型、无毒、双齿配体的Ln(III)复合物(LnL3,Ln = La、Eu、Gd、Tb、Yb,L = 3-氧-2-甲基-4-吡喃酮(ma−),3-氧-2-乙基-4-吡喃酮(ema−),3-氧-1,2-二甲基-4-吡啶酮(dpp−)和3-氧-2-甲基-4(1H)-吡啶酮(mpp−))。初步生物分析包括细胞毒性、细胞摄取和Caco-2细胞中的双向转运研究,以及体外羟基磷灰石(HA)结合研究。结合HA的完整化合物比例是通过ICP-MS测定Ln(III)浓度与溶液中前配体的UV-vis光谱法测定来计算的。发现LnL3物种的IC50值至少比顺铂大6倍,HA结合能力≥98%,透过系数处于中等范围内。经过测试后,La(dpp)3被确定为治疗骨密度疾病的领先化合物,其细胞摄取百分比最高为9.07 ± 2.33%,初步Papp值最高为3.54 ± 2.86 × 10−6 cm s−1。