Abstract：
OBJECTIVE: Mandibular condylar cartilage (MCC) of the rat was examined with the Fourier-transform infrared (FITR) spectroscopic imaging to study the effects of ageing, oestrogen level and altered dietary loading on the structure of MCC.
METHODS: The Sprague-Dawley rats (n = 96) aged 5 and 14 months were divided into 12 subgroups according to age, oestrogen status (ovariectomized [OVX], non-ovariectomized [non-OVX)]) and diet (hard, normal, soft). Specimens of the MCC were examined with FTIR spectroscopic imaging to quantify the distribution of collagens and proteoglycans. MCC was divided sagittally into three segments: anterior, most superior and posterior. From each segment, the collagen and proteoglycan contents at different depths of cartilage were statistically compared between the groups using an N-way analysis of variance (ANOVA).
RESULTS: The amount of collagen content was significantly associated with old age in the deep layer of the anterior segment and in the middle layer of the posterior segment of MCC. In the deep layer of the most superior segment, the collagen content also increased with ageing. The amount of proteoglycan content increased significantly when dietary loading increased, and the oestrogen level decreased in the deep layer of the most superior segment of MCC.
CONCLUSIONS: Ageing, oestrogen level and altered dietary loading have a significant effect on the location and content of collagens and proteoglycans of rat MCC. Ageing significantly increased the amount of collagen content in the superior and posterior segments, being highest in the older soft-diet rats. Decreased oestrogen levels and increased dietary loading increased the amount of proteoglycan content.
METHODS: The Sprague-Dawley rats (n = 96) aged 5 and 14 months were divided into 12 subgroups according to age, oestrogen status (ovariectomized [OVX], non-ovariectomized [non-OVX)]) and diet (hard, normal, soft). Specimens of the MCC were examined with FTIR spectroscopic imaging to quantify the distribution of collagens and proteoglycans. MCC was divided sagittally into three segments: anterior, most superior and posterior. From each segment, the collagen and proteoglycan contents at different depths of cartilage were statistically compared between the groups using an N-way analysis of variance (ANOVA).
RESULTS: The amount of collagen content was significantly associated with old age in the deep layer of the anterior segment and in the middle layer of the posterior segment of MCC. In the deep layer of the most superior segment, the collagen content also increased with ageing. The amount of proteoglycan content increased significantly when dietary loading increased, and the oestrogen level decreased in the deep layer of the most superior segment of MCC.
CONCLUSIONS: Ageing, oestrogen level and altered dietary loading have a significant effect on the location and content of collagens and proteoglycans of rat MCC. Ageing significantly increased the amount of collagen content in the superior and posterior segments, being highest in the older soft-diet rats. Decreased oestrogen levels and increased dietary loading increased the amount of proteoglycan content.
摘要：
目的：用傅立叶变换红外（FITR）光谱成像检查大鼠下颌髁突软骨（MCC），以研究衰老的影响，雌激素水平和饮食负荷对MCC结构的影响。
方法：将5和14月龄的Sprague-Dawley大鼠（n=96）按年龄分为12个亚组，雌激素状态（卵巢切除[OVX]，非卵巢切除[非OVX)])和饮食(硬，正常,软)。用FTIR光谱成像检查MCC的样本以量化胶原蛋白和蛋白聚糖的分布。MCC矢状分为三段：前段，最上和后。从每个片段中，采用N路方差分析(ANOVA)对各组不同软骨深度的胶原和蛋白聚糖含量进行统计学比较.
结果：在MCC的前段深层和后段中间层，胶原蛋白含量的量与年龄显着相关。在最高级的深层，胶原蛋白含量也随着年龄的增长而增加。当膳食负荷增加时，蛋白聚糖含量显著增加，MCC最上段深层雌激素水平下降。
结论：老龄化，雌激素水平和饮食负荷的改变对大鼠MCC的胶原蛋白和蛋白聚糖的位置和含量有显着影响。老化显著增加上段和后段胶原含量，在老年软饮食大鼠中最高。雌激素水平的降低和饮食负荷的增加增加了蛋白聚糖的含量。
方法：将5和14月龄的Sprague-Dawley大鼠（n=96）按年龄分为12个亚组，雌激素状态（卵巢切除[OVX]，非卵巢切除[非OVX)])和饮食(硬，正常,软)。用FTIR光谱成像检查MCC的样本以量化胶原蛋白和蛋白聚糖的分布。MCC矢状分为三段：前段，最上和后。从每个片段中，采用N路方差分析(ANOVA)对各组不同软骨深度的胶原和蛋白聚糖含量进行统计学比较.
结果：在MCC的前段深层和后段中间层，胶原蛋白含量的量与年龄显着相关。在最高级的深层，胶原蛋白含量也随着年龄的增长而增加。当膳食负荷增加时，蛋白聚糖含量显著增加，MCC最上段深层雌激素水平下降。
结论：老龄化，雌激素水平和饮食负荷的改变对大鼠MCC的胶原蛋白和蛋白聚糖的位置和含量有显着影响。老化显著增加上段和后段胶原含量，在老年软饮食大鼠中最高。雌激素水平的降低和饮食负荷的增加增加了蛋白聚糖的含量。
