Research Unit of Population Health, Faculty of Medicine, University of Oulu, Oulu, Finland.
Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.
Orthod Craniofac Res. 2024 Feb;27(1):151-164. doi: 10.1111/ocr.12693. Epub 2023 Aug 11.
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.
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).
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.
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.
应用傅里叶变换红外（FTIR）光谱成像技术研究年龄、雌激素水平和饮食负荷改变对大鼠髁突软骨（MCC）结构的影响。
将 5 月龄和 14 月龄的 Sprague-Dawley 大鼠（n=96）分为 12 组，根据年龄、雌激素状态（卵巢切除术[OVX]、非卵巢切除术[non-OVX]）和饮食（硬食、正常、软食）进行分组。用 FTIR 光谱成像技术检测 MCC 标本，以定量分析胶原蛋白和蛋白聚糖的分布。将 MCC 矢状位分为前、最上和后三个节段。从每个节段，用 N -way ANOVA 分析比较各组软骨不同深度的胶原蛋白和蛋白聚糖含量。
在 MCC 前节段深层和后节段中层，胶原蛋白含量与年龄呈显著正相关。在最上节段深层，胶原蛋白含量也随年龄增长而增加。随着饮食负荷的增加，蛋白聚糖含量显著增加，而 MCC 最上节段深层的雌激素水平下降。
年龄、雌激素水平和饮食负荷改变对大鼠 MCC 中胶原蛋白和蛋白聚糖的位置和含量有显著影响。年龄的增加显著增加了 MCC 上后节段的胶原蛋白含量，在较老的软食大鼠中最高。雌激素水平下降和饮食负荷增加增加了蛋白聚糖含量。
