Gavin Herbert Eye Institute, University of California, Irvine, Irvine, California.
Anat Rec (Hoboken). 2011 Feb;294(2):185-92. doi: 10.1002/ar.21305. Epub 2010 Nov 16.
Recent studies suggest that mouse meibomian glands (MG) undergo age-related atrophy that mimics changes seen in age-related human MG dysfunction (MGD). To better understand the structural/functional changes that occur during aging, this study developed an imaging approach to generate quantifiable volumetric reconstructions of the mouse MG and measure total gland, cell, and lipid volume. Mouse eyelids were fixed in 4% paraformaldehyde, embedded in LR White resin and serially sectioned. Sections were then scanned using a 20× objective and a series of tiled images (1.35 × 1.35 × 0.5 mm) with a pixel size of 0.44 microm lateral and 2 microm axial were collected using a Zeiss 510 Meta LSM and a femtosecond laser to simultaneously detect second harmonic generated (SHG) and two-photon excited fluorescence (TPEF) signals from the tissue sections. The SHG signal from collagen was used to outline and generate an MG mask to create surface renderings of the total gland and extract relevant MG TPEF signals that were later separated into the cellular and lipid compartments. Using this technique, three-dimensional reconstructions of the mouse MG were obtained and the total, cell, and lipid volume of the MG measured. Volumetric reconstructions of mouse MG showed loss of acini in old mice that were not detected by routine histology. Furthermore, older mouse MG had reduced total gland volume that is primarily associated with loss of the lipid volume. These findings suggest that mice MG undergo "dropout" of acini, similar to that which occurs in human age-related MGD.
最近的研究表明，小鼠的睑板腺（MG）会发生与年龄相关的萎缩，这种萎缩类似于与年龄相关的人类 MG 功能障碍（MGD）中观察到的变化。为了更好地了解衰老过程中发生的结构/功能变化，本研究开发了一种成像方法，对小鼠 MG 进行可量化的容积重建，并测量总腺体、细胞和脂质体积。将小鼠眼睑固定在 4%多聚甲醛中，嵌入 LR White 树脂中并进行连续切片。然后使用 20×物镜和一系列平铺图像（1.35×1.35×0.5 毫米）对切片进行扫描，使用 Zeiss 510 Meta LSM 和飞秒激光以同时检测来自组织切片的二次谐波产生（SHG）和双光子激发荧光（TPEF）信号，其中每个像素的大小为 0.44 微米的横向和 2 微米的轴向。从组织切片中同时检测来自组织切片的二次谐波产生（SHG）和双光子激发荧光（TPEF）信号，其中每个像素的大小为 0.44 微米的横向和 2 微米的轴向。从组织切片中同时检测来自组织切片的二次谐波产生（SHG）和双光子激发荧光（TPEF）信号，其中每个像素的大小为 0.44 微米的横向和 2 微米的轴向。胶原的 SHG 信号用于勾勒并生成 MG 掩模，以创建总腺体的表面渲染图，并提取相关的 MG TPEF 信号，这些信号后来被分离成细胞和脂质隔室。使用该技术，获得了小鼠 MG 的三维重建，并测量了 MG 的总、细胞和脂质体积。小鼠 MG 的体积重建显示，在常规组织学无法检测到的老年小鼠中，腺泡丢失。此外，老年小鼠的 MG 总腺体体积减小，主要与脂质体积减少有关。这些发现表明，小鼠的 MG 经历了类似人类年龄相关性 MGD 中发生的腺泡“脱落”。
