Rodrigo A M, Martínez M E, Martínez P, Escudero M L, Ruíz J, Saldaña L, Gómez-García L, Fernández L, del Valle I, Munuera L
Investigation Unit Hospital La Paz, Madrid, Spain.
J Biomed Mater Res. 2001 Jan;54(1):30-6. doi: 10.1002/1097-4636(200101)54:1<30::aid-jbm4>3.0.co;2-v.
One of the problems associated with the modern biomaterials used in prostheses is osteolysis, which, although its exact origin is unknown, has been associated with wear particles. Osteoblasts seem to participate directly in this phenomenon. This paper investigates in vitro cellular response to the wear particles from the metal substrate and ceramic covering (alpha-alumina) of a new titanium yttrium aluminum alloy, MA 956, that has been proposed as a biomaterial because of its exceptional mechanical and electrochemical properties. The effect of different sizes (10 and 80 microm) of MA 956 and alpha-alumina particles on osteoblast function was studied in primary human bone cell cultures. Cells were harvested from trabecular bone fragments obtained during knee arthroplasty. Osteoblastic cell response to the particles was measured by assaying C-terminal type I procollagen (PICP), alkaline phosphatase, and osteocalcin secretion, with and without 1.25(OH)(2)D(3) stimulation, in the cell-conditioned medium. Both sizes of MA 956 and alpha-alumina particles decreased PICP secretion in nonstimulated osteoblastic cells, but this secretion was not affected in the cultures stimulated with 1.25(OH)(2)D(3). Only the 10 microm alpha-alumina particles inhibited alkaline phosphatase activity in 1.25(OH)(2)D(3)-stimulated and nonstimulated cultures. The rise in osteocalcin levels after 1.25(OH)(2)D(3) stimulation was lower in the presence of the 10 microm MA 956 particles than in the presence of alpha-alumina particles. Although both materials seem to have directly affected in vitro osteoblastic cell function, the increase in osteocalcin levels after 1.25(OH)(2)D(3) stimulation was lower after exposure to MA 956 particles than the increase observed after exposure to alpha-alumina particles. Therefore, it does not seem that osteocalcin stimulated bone resorption, suggesting that MA 956 would be less likely to provoke osteolysis.
与假体中使用的现代生物材料相关的问题之一是骨溶解，尽管其确切起源尚不清楚，但一直与磨损颗粒有关。成骨细胞似乎直接参与了这一现象。本文研究了一种新型钛钇铝合金MA 956的金属基底和陶瓷涂层（α-氧化铝）产生的磨损颗粒在体外的细胞反应，该合金因其优异的机械和电化学性能而被提议作为生物材料。在原代人骨细胞培养物中研究了不同尺寸（10和80微米）的MA 956和α-氧化铝颗粒对成骨细胞功能的影响。细胞取自膝关节置换术中获得的小梁骨碎片。通过检测细胞条件培养基中I型前胶原C端（PICP）、碱性磷酸酶和骨钙素的分泌情况，在有和没有1.25(OH)₂D₃刺激的情况下，测量成骨细胞对颗粒的反应。MA 956和α-氧化铝颗粒的两种尺寸均降低了未刺激的成骨细胞中PICP的分泌，但在1.25(OH)₂D₃刺激的培养物中，这种分泌不受影响。只有10微米的α-氧化铝颗粒在1.25(OH)₂D₃刺激和未刺激的培养物中抑制了碱性磷酸酶活性。在1.25(OH)₂D₃刺激后，10微米MA 956颗粒存在时骨钙素水平的升高低于α-氧化铝颗粒存在时。尽管两种材料似乎都直接影响了体外成骨细胞的功能，但在暴露于MA 956颗粒后，1.25(OH)₂D₃刺激后骨钙素水平的升高低于暴露于α-氧化铝颗粒后观察到的升高。因此，骨钙素似乎并未刺激骨吸收，这表明MA 956引发骨溶解的可能性较小。
