染料木素对大鼠髁突软骨改建影响的初步研究

Preliminary Sdudy on the Effect of Genistein on Rat Condylar Cartilage Remodeling

目的初步探讨染料木素对大鼠TM J髁突软骨改建的影响。方法 30只8周龄雌性大鼠,随机分为操作对照组、去势组和去势+染料木素组,去势组和去势+染料木素组大鼠行双侧卵巢切除术,术后每天给予去势+染料木素组大鼠20mg/kg的染料木素,6周后取材。HE染色观察组织形态变化,通过免疫组化和实时定量PCR分别检测Ⅱ型胶原、蛋白聚糖、ERα和ERβ的蛋白和mRNA水平变化。结果①去势组髁突软骨前部、中部厚度对显著高于操作对照组和去势+染料木素组;②去势组髁突软骨中Ⅱ型胶原及ERα、ERβ的平均阳性面积百分比显著低于操作对照组和去势+染料木素组;③去势组髁突软骨中Ⅱ型胶原、aggrecan的mRNA水平显著低于操作对照组和去势+染料木素组;④去势组髁突软骨中ERβ的mRNA水平显著低于操作对照组和去势+染料木素组,但ERα在各组之间无显著差异。结论①卵巢切除所引起大鼠髁突软骨增厚过程中新合成的软骨基质成分可能不同于正常大鼠髁突软骨;②一定剂量的染料木素可以基本恢复系统雌激素缺乏所造成的髁突软骨组织形态及软骨基质成分的改变,在此过程中染料木素可能主要通过ERβ发挥作用。

Objective To investigate the effect of genistein on rat condylar cartilage remodeling. Methods Thirty female rats, 8 weeks old, were assigned randomly into sham control group, ovariectomized （OVX） group, OVX and genistein treatment （OVX ＋ Gen） group. The rats from OVX and OVX ＋ Gen groups were ovariectomized. The animals in OVX ＋ Gen group were fed with 20mg/kg genistein per day. All animals were sacrificed 6 weeks later. HE staining was carried out to investigate the morphology of condylar carti- lage, and immunohistochemical staining and real - time PCR were performed to investigate the expression of collagen Ⅱ （ Col Ⅱ ） , aggrecan, ERα and ERβ at protein and mRNA level. Results （1）The thickness of condylar cartilage in anterior and middle region of OVX group was higher than that of sham control and OVX ＋ Gen group, （2）The average percent of Col II , ERα and ERβ - positive area in OVX group was lower than that in sham control and OVX ＋ Gen group. （3） The mRNA level of Col II and aggreean in OVX group was lower than that in sham control and OVX ＋ Gen group. （4） The mRNA level of ERβ in OVX group was lower than that in sham control and OVX ＋ Gen group, but not for ERos. Conclusion （1） The new synthesized cartilage matrix may be different from that in normal condylar cartilage,（ 2）The changes of morphology and cartilage matrix induced by system estrogen deficiency can be recovered by certain dose of genistein via ERβ.