Driscoll Meghan K, Albanese Jason L, Xiong Zheng-Mei, Mailman Mitch, Losert Wolfgang, Cao Kan
Department of Physics, University of Maryland, College Park, MD 20742, USA.
Aging (Albany NY). 2012 Feb;4(2):119-32. doi: 10.18632/aging.100434.
The premature aging disorder, Hutchinson-Gilford progeria syndrome (HGPS), is caused by mutant lamin A, which affects the nuclear scaffolding. The phenotypic hallmark of HGPS is nuclear blebbing. Interestingly, similar nuclear blebbing has also been observed in aged cells from healthy individuals. Recent work has shown that treatment with rapamycin, an inhibitor of the mTOR pathway, reduced nuclear blebbing in HGPS fibroblasts. However, the extent of blebbing varies considerably within each cell population, which makes manual blind counting challenging and subjective. Here, we show a novel, automated and high throughput nuclear shape analysis that quantitatively measures curvature, area, perimeter, eccentricity and additional metrics of nuclear morphology for large populations of cells. We examined HGPS fibroblast cells treated with rapamycin and RAD001 (an analog to rapamycin). Our analysis shows that treatment with RAD001 and rapamycin reduces nuclear blebbing, consistent with blind counting controls. In addition, we find that rapamycin treatment reduces the area of the nucleus, but leaves the eccentricity unchanged. Our nuclear shape analysis provides an unbiased, multidimensional "fingerprint" for a population of cells, which can be used to quantify treatment efficacy and analyze cellular aging.
早衰症，即哈钦森-吉尔福德早衰综合征（HGPS），是由突变的核纤层蛋白A引起的，它会影响核支架结构。HGPS的表型特征是核膜泡化。有趣的是，在健康个体的衰老细胞中也观察到了类似的核膜泡化现象。最近的研究表明，用雷帕霉素（一种mTOR通路抑制剂）处理可减少HGPS成纤维细胞中的核膜泡化。然而，每个细胞群体中的膜泡化程度差异很大，这使得人工盲目计数既具有挑战性又主观。在这里，我们展示了一种新颖的、自动化的高通量核形状分析方法，该方法可以对大量细胞的曲率、面积、周长、偏心率和其他核形态指标进行定量测量。我们研究了用雷帕霉素和RAD001（雷帕霉素类似物）处理的HGPS成纤维细胞。我们的分析表明，RAD001和雷帕霉素处理可减少核膜泡化，这与盲目计数对照结果一致。此外，我们发现雷帕霉素处理会减小细胞核的面积，但偏心率不变。我们的核形状分析为细胞群体提供了一个无偏差的、多维的“指纹”，可用于量化治疗效果和分析细胞衰老。
