Department of Physical Therapy, University of Florida, Gainesville, FL, USA.
Breathing Research and Therapeutics Center, University of Florida, Gainesville, FL, USA.
J Neuroinflammation. 2023 Dec 19;20(1):303. doi: 10.1186/s12974-023-02985-6.
Acute hyperbaric O (HBO) therapy after spinal cord injury (SCI) can reduce inflammation and increase neuronal survival. To our knowledge, it is unknown if these benefits of HBO require hyperbaric vs. normobaric hyperoxia. We used a C4 lateralized contusion SCI in adult male and female rats to test the hypothesis that the combination of hyperbaria and 100% O (i.e. HBO) more effectively mitigates spinal inflammation and neuronal loss, and enhances respiratory recovery, as compared to normobaric 100% O. Experimental groups included spinal intact, SCI no O therapy, and SCI + 100% O delivered at normobaric pressure (1 atmosphere, ATA), or at 2- or 3 ATA. O treatments lasted 1-h, commenced within 2-h of SCI, and were repeated for 10 days. The spinal inflammatory response was assessed with transcriptomics (RNAseq) and immunohistochemistry. Gene co-expression network analysis showed that the strong inflammatory response to SCI was dramatically diminished by both hyper- and normobaric O therapy. Similarly, both HBO and normobaric O treatments reduced the prevalence of immunohistological markers for astrocytes (glial fibrillary acidic protein) and microglia (ionized calcium binding adaptor molecule) in the injured spinal cord. However, HBO treatment also had unique impacts not detected in the normobaric group including upregulation of an anti-inflammatory cytokine (interleukin-4) in the plasma, and larger inspiratory tidal volumes at 10-days (whole body-plethysmography measurements). We conclude that normobaric O treatment can reduce the spinal inflammatory response after SCI, but pressured O (i.e., HBO) provides further benefit.
急性高压氧（HBO）治疗脊髓损伤（SCI）后可以减轻炎症并增加神经元存活。据我们所知，尚不清楚 HBO 的这些益处是否需要高压与常压高氧。我们使用成年雄性和雌性大鼠的 C4 侧方挫伤 SCI 来测试以下假设：与常压 100%O（即 HBO）相比，高压与 100%O 的联合更有效地减轻脊髓炎症和神经元损失，并增强呼吸恢复。实验组包括脊髓完整、无 O 治疗的 SCI 以及在常压（1 个大气压，ATA）或 2 或 3ATA 下给予的 100%O。O 治疗持续 1 小时，在 SCI 后 2 小时内开始，并重复 10 天。使用转录组学（RNAseq）和免疫组织化学评估脊髓炎症反应。基因共表达网络分析表明，高压和常压 O 治疗均可显著减轻 SCI 的强烈炎症反应。同样，HBO 和常压 O 治疗均可减少损伤脊髓中星形胶质细胞（胶质纤维酸性蛋白）和小胶质细胞（离子钙结合衔接蛋白分子）的免疫组织化学标志物的发生率。然而，HBO 治疗还具有在常压组中未检测到的独特影响，包括血浆中抗炎细胞因子（白细胞介素 4）的上调以及 10 天时更大的吸气潮气量（全身 plethysmography 测量）。我们的结论是，常压 O 治疗可减轻 SCI 后的脊髓炎症反应，但加压 O（即 HBO）可提供进一步的益处。
