LaRosa Domenic A, Ellery Stacey J, Snow Rod J, Walker David W, Dickinson Hayley
Ritchie Centre, Hudson Institute of Medical Research and Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia.
Centre for Physical Activity and Nutrition, Deakin University, Burwood, Australia.
Pediatr Res. 2016 Dec;80(6):852-860. doi: 10.1038/pr.2016.153. Epub 2016 Jul 28.
Maternal antenatal creatine supplementation protects the brain, kidney, and diaphragm against the effects of birth asphyxia in the spiny mouse. In this study, we examined creatine's potential to prevent damage to axial skeletal muscles.
Pregnant spiny mice were fed a control or creatine-supplemented diet from mid-pregnancy, and 1 d before term (39 d), fetuses were delivered by c-section with or without 7.5 min of birth asphyxia. At 24 h or 33 ± 2 d after birth, gastrocnemius muscles were obtained for ex-vivo study of twitch-tension, muscle fatigue, and structural and histochemical analysis.
Birth asphyxia significantly reduced cross-sectional area of all muscle fiber types (P < 0.05), and increased fatigue caused by repeated tetanic contractions at 24 h of age (P < 0.05). There were fewer (P < 0.05) Type I and IIa fibers and more (P < 0.05) Type IIb fibers in male gastrocnemius at 33 d of age. Muscle oxidative capacity was reduced (P < 0.05) in males at 24 h and 33 d and in females at 24 h only. Maternal creatine treatment prevented all asphyxia-induced changes in the gastrocnemius, improved motor performance.
This study demonstrates that creatine loading before birth protects the muscle from asphyxia-induced damage at birth.
母体产前补充肌酸可保护刺毛鼠的大脑、肾脏和膈肌免受出生时窒息的影响。在本研究中，我们检测了肌酸预防轴向骨骼肌损伤的潜力。
怀孕的刺毛鼠从妊娠中期开始喂食对照饮食或补充肌酸的饮食，在足月前1天（39天），通过剖宫产分娩胎儿，分娩时有无7.5分钟的出生窒息。在出生后24小时或33±2天时，获取腓肠肌进行离体研究，包括抽搐张力、肌肉疲劳以及结构和组织化学分析。
出生窒息显著降低了所有肌纤维类型的横截面积（P<0.05），并增加了24小时龄时由重复强直收缩引起的疲劳（P<0.05）。33日龄雄性腓肠肌中I型和IIa型纤维较少（P<0.05），IIb型纤维较多（P<0.05）。仅在24小时龄时，雄性和雌性的肌肉氧化能力均降低（P<0.05），在33日龄时，仅雄性的肌肉氧化能力降低（P<0.05）。母体肌酸治疗可预防所有窒息引起的腓肠肌变化，改善运动表现。
本研究表明，出生前补充肌酸可保护肌肉免受出生时窒息引起的损伤。
