Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA.
Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA.
Theranostics. 2021 Jan 1;11(3):1269-1294. doi: 10.7150/thno.49672. eCollection 2021.
Neonatal hypoxic-ischemic (HI) injury is a severe complication often leading to neonatal death and long-term neurobehavioral deficits in children. Currently, the only treatment option available for neonatal HI injury is therapeutic hypothermia. However, the necessary specialized equipment, possible adverse side effects, and limited effectiveness of this therapy creates an urgent need for the development of new HI treatment methods. Photobiomodulation (PBM) has been shown to be neuroprotective against multiple brain disorders in animal models, as well as limited human studies. However, the effects of PBM treatment on neonatal HI injury remain unclear. Two-minutes PBM (808 nm continuous wave laser, 8 mW/cm on neonatal brain) was applied three times weekly on the abdomen of pregnant rats from gestation day 1 (GD1) to GD21. After neonatal right common carotid artery ligation, cortex- and hippocampus-related behavioral deficits due to HI insult were measured using a battery of behavioral tests. The effects of HI insult and PBM pretreatment on infarct size; synaptic, dendritic, and white matter damage; neuronal degeneration; apoptosis; mitochondrial function; mitochondrial fragmentation; oxidative stress; and gliosis were then assessed. Prenatal PBM treatment significantly improved the survival rate of neonatal rats and decreased infarct size after HI insult. Behavioral tests revealed that prenatal PBM treatment significantly alleviated cortex-related motor deficits and hippocampus-related memory and learning dysfunction. In addition, mitochondrial function and integrity were protected in HI animals treated with PBM. Additional studies revealed that prenatal PBM treatment significantly alleviated HI-induced neuroinflammation, oxidative stress, and myeloid cell/astrocyte activation. Prenatal PBM treatment exerts neuroprotective effects on neonatal HI rats. Underlying mechanisms for this neuroprotection may include preservation of mitochondrial function, reduction of inflammation, and decreased oxidative stress. Our findings support the possible use of PBM treatment in high-risk pregnancies to alleviate or prevent HI-induced brain injury in the perinatal period.
新生儿缺氧缺血性(HI)损伤是一种严重的并发症,常导致新生儿死亡和儿童长期神经行为缺陷。目前,新生儿 HI 损伤唯一可用的治疗选择是治疗性低温。然而,这种治疗所需的专门设备、可能的不良反应以及治疗效果的局限性,都迫切需要开发新的 HI 治疗方法。光生物调节(PBM)已在动物模型中被证明对多种脑部疾病具有神经保护作用,同时也有一些有限的人类研究。然而,PBM 治疗对新生儿 HI 损伤的影响尚不清楚。在妊娠第 1 天(GD1)至第 21 天(GD21),对怀孕大鼠的腹部进行两分钟的 PBM(808nm 连续波激光,8mW/cm ² 于新生儿脑部),每周三次。在新生大鼠右侧颈总动脉结扎后,通过一系列行为测试评估 HI 损伤引起的皮质和海马相关行为缺陷。然后评估 HI 损伤和 PBM 预处理对梗死面积、突触、树突和白质损伤、神经元变性、细胞凋亡、线粒体功能、线粒体碎片化、氧化应激和神经胶质增生的影响。产前 PBM 治疗显著提高了新生大鼠的存活率,并减少了 HI 损伤后的梗死面积。行为测试显示,产前 PBM 治疗显著减轻了皮质相关运动缺陷和海马相关记忆和学习功能障碍。此外,PBM 处理的 HI 动物的线粒体功能和完整性得到了保护。进一步的研究表明,产前 PBM 治疗显著减轻了 HI 诱导的神经炎症、氧化应激和髓样细胞/星形胶质细胞激活。产前 PBM 治疗对新生 HI 大鼠具有神经保护作用。这种神经保护的潜在机制可能包括维持线粒体功能、减少炎症和降低氧化应激。我们的研究结果支持在高危妊娠中使用 PBM 治疗,以减轻或预防围产期 HI 引起的脑损伤。