Laboratory of Respiratory Diseases and Thoracic surgery, Department of Chronic Diseases and Metabolism, KU-Leuven, Leuven, Belgium.
Neurorehabilitation group, Department of Rehabilitation Sciences, KU-Leuven, Leuven, Belgium.
Am J Physiol Cell Physiol. 2024 Feb 1;326(2):C573-C588. doi: 10.1152/ajpcell.00344.2023. Epub 2023 Dec 18.
Inconsistent alterations in skeletal muscle histology have been reported in adolescents with cerebral palsy (CP) and whether alterations are present in young children and differ from older children is not yet known. This study aimed to define histological alterations in the medial gastrocnemius (MG) of ambulant CP (gross-motor classification system, GMFCS I-III) stratified in two age groups (preschool children, PS: 2-5 and school age children, SA: 6-9-yr old) compared with age-matched typically developing (TD) children. We hypothesized that alterations in muscle microscopic properties are already present in PS-CP and are GMFCS level specific. Ultrasound guided percutaneous microbiopsies were collected in 46 CP (24-PS) and 45 TD (13-PS) children. Sections were stained to determine fiber cross-sectional area (fCSA) and proportion, capillary, and satellite cell amount. Average absolute and normalized fCSA were similar in CP and TD, but a greater percentage of smaller fibers was found in CP. Coefficient of variation (CV) was significantly larger in PS-CP-GMFCS I-II and for type I fiber. In SA-CP, all fiber types contributed to the higher CV. Type IIx proportion was higher and type I was lower in PS-CP-GMFCS-III and for all SA-CP. Reduced capillary-to-fiber ratio was present in PS-CP-GMFCS II-III and in all SA-CP. Capillary fiber density was lower in SA-CP. Capillary domain was enhanced in all CP, but capillary spatial distribution was maintained as was satellite cell content. We concluded that MG histological alterations are already present in very young CP but are only partly specific for GMFCS level and age. Inconsistent histological alterations have been reported in children with cerebral palsy (CP) but whether they are present in very young and ambulant CP children and differ from those reported in old CP children is not known. This study highlighted for the first time that enhanced muscle fiber size variability and loss of capillaries are already present in very young CP children, even in the most ambulant ones, and these alterations seem to extend with age.
在脑瘫（CP）青少年中，已经报道了骨骼肌组织学的不一致改变，而这些改变是否存在于年幼的儿童中，以及是否与年长的儿童不同，目前尚不清楚。本研究旨在定义在两个年龄组（学龄前儿童，PS：2-5 岁和学龄儿童，SA：6-9 岁）的 CP 中，内侧腓肠肌（MG）的组织学改变，并与年龄匹配的正常发育（TD）儿童进行比较。我们假设肌肉微观特性的改变在 PS-CP 中已经存在，并且与 GMFCS 水平特异性相关。我们使用超声引导经皮微创活检收集了 46 名 CP（24 名 PS）和 45 名 TD（13 名 PS）儿童的肌肉组织。对组织切片进行染色，以确定纤维横截面积（fCSA）和比例、毛细血管和卫星细胞数量。CP 和 TD 儿童的平均绝对和标准化 fCSA 相似，但 CP 儿童中较小纤维的比例较大。PS-CP-GMFCS I-II 和 I 型纤维的变异系数（CV）显著较大。在 SA-CP 中，所有纤维类型都导致了更高的 CV。PS-CP-GMFCS-III 和所有 SA-CP 中的 IIx 型比例较高，而 I 型比例较低。PS-CP-GMFCS II-III 和所有 SA-CP 中毛细血管与纤维的比例均降低。SA-CP 中毛细血管纤维密度较低。所有 CP 中毛细血管域增加，但毛细血管空间分布得到维持，卫星细胞含量也保持不变。我们的结论是，MG 组织学改变已经存在于非常年幼的 CP 中，但仅部分具有 GMFCS 水平和年龄特异性。在脑瘫（CP）儿童中已经报道了不一致的组织学改变，但这些改变是否存在于非常年幼和能活动的 CP 儿童中，以及与老年 CP 儿童的改变是否不同，目前尚不清楚。本研究首次强调，即使在最活跃的 CP 儿童中，肌肉纤维大小变异性的增强和毛细血管的丧失也已经存在于非常年幼的 CP 儿童中，并且这些改变似乎随着年龄的增长而扩展。
