Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA.
Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT, 84132, USA.
Sci Rep. 2022 Mar 29;12(1):5327. doi: 10.1038/s41598-022-09328-0.
Electrical impedance methods, including electrical impedance myography, are increasingly being used as biomarkers of muscle health since they measure passive electrical properties of muscle that alter in disease. One disorder, Pompe Disease (Glycogen storage disease type II (GSDII)), remains relatively unstudied. This disease is marked by dramatic accumulation of intracellular myofiber glycogen. Here we assessed the electrical properties of skeletal muscle in a model of GSDII, the Pompe (Pompe) mouse. Ex vivo impedance measurements of gastrocnemius (GA) were obtained using a dielectric measuring cell in 30-week-old female Pompe (N = 10) and WT (N = 10) mice. Longitudinal and transverse conductivity, σ, and the relative permittivity, ε, and Cole-Cole complex resistivity parameters at 0 Hz and infinite frequency, ρ and ρ, respectively, and the intracellular resistivity, ρ were determined from the impedance data. Glycogen content (GC) was visualized histologically and quantified biochemically. At frequencies > 1 MHz, Pompe mice demonstrated significantly decreased longitudinal and transverse conductivity, increased Cole-Cole parameters, ρ and ρ-ρ, and decreased ρ. Changes in longitudinal conductivity and ρ correlated with increased GC in Pompe animals. Ex vivo high frequency impedance measures are sensitive to alterations in intracellular myofiber features considered characteristic of GSDII, making them potentially useful measures of disease status.
电阻抗方法，包括电阻抗肌电图，越来越多地被用作肌肉健康的生物标志物，因为它们测量肌肉的被动电学特性，这些特性在疾病中会发生改变。一种疾病，庞贝病（糖原贮积病 II 型（GSDII）），仍然相对未被研究。这种疾病的特点是细胞内肌纤维糖原的大量积累。在这里，我们评估了 GSDII 模型中骨骼肌的电学特性，即庞贝（Pompe）小鼠。使用介电测量单元对 30 周龄雌性庞贝（Pompe）（N = 10）和 WT（N = 10）小鼠的腓肠肌（GA）进行了离体阻抗测量。分别在 0 Hz 和无穷频率下，从阻抗数据中确定了纵向和横向电导率σ，相对介电常数ε，Cole-Cole 复电阻率参数ρ和ρ，以及细胞内电阻率ρ。通过组织学可视化和生物化学定量分析了糖原含量（GC）。在频率> 1 MHz 时，庞贝小鼠表现出明显降低的纵向和横向电导率、增加的 Cole-Cole 参数ρ和ρ-ρ，以及降低的ρ。纵向电导率和ρ的变化与庞贝动物中 GC 的增加相关。离体高频阻抗测量对被认为是 GSDII 特征的细胞内肌纤维特征的改变敏感，使它们成为疾病状态的潜在有用测量指标。
