The effects of hyperbaric oxygen on macrophage polarization after rat spinal cord injury.
The immunoreactive responses are a two-edged sword after spinal cord injury (SCI). Macrophages are the predominant inflammatory cells responsible for this response. However, the mechanism underlying the effects of HBOT on the immunomodulation following SCI is unclear now. The present study was performed to examine the effects of hyperbaric oxygen therapy (HBOT) on macrophage polarization after the rat compressive injury of the spinal cord. HBOT was associated with significant increases in IL-4 and IL-13 levels, and reductions in TNF-α and IFN-ɣ levels. This was associated simultaneously with the levels of alternatively activated macrophages (M2 phenotype: arginase-1- or CD206-positive), and decreased levels of classically activated macrophages (M1 phenotype: iNOS- or CD16/32-positive). These changes were associated with functional recovery in the HBOT-transplanted group, which correlated with preserved axons and increased myelin sparing. Our results suggested that HBOT after SCI modified the inflammatory environment by shifting the macrophage phenotype from M1 to M2, which may further promote the axonal extension and functional recovery.
Department of Orthopedics, Yan׳an Hospital of Kunming City, the Affiliated Hospital of Kunming Medical University, Kunming 650032, China; Department of Minimally Invasive Neurosurgery, The First Affiliated Hospital of Kunming Medical University, No. 295, Xichang Road, Kunming 650032, China.
Cheng-Kui
CK
Geng
Department of Hematology, Tumor Hospital of Yunnan Province & The Third Affiliated Hospital of Kunming Medical University, Kunming 650118, China.
Hong-Hua
HH
Cao
Department of Orthopedics, Yan׳an Hospital of Kunming City, the Affiliated Hospital of Kunming Medical University, Kunming 650032, China.
Xiong
X
Ying
Department of Minimally Invasive Neurosurgery, The First Affiliated Hospital of Kunming Medical University, No. 295, Xichang Road, Kunming 650032, China; The Affiliated Bayi Brain Hospital, The General Hospital of Beijing PLA, Beijing 100700, China. Electronic address: xiaohaijun_neu@126.com.
Hong-Tian
HT
Zhang
Department of Minimally Invasive Neurosurgery, The First Affiliated Hospital of Kunming Medical University, No. 295, Xichang Road, Kunming 650032, China. Electronic address: zhanghongtian007@126.com.
Hua-Lin
HL
Yu
D000818:Animals; D001369:Axons / Q000473:pathology; D016764:Cell Polarity; D016207:Cytokines / Q000378:metabolism; D006931:Hyperbaric Oxygenation; D007249:Inflammation / Q000378:metabolism; D008124:Locomotion; D008264:Macrophages / Q000378:metabolism / Q000502:physiology*; D009186:Myelin Sheath / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013119:Spinal Cord Injuries / Q000276:immunology* / Q000378:metabolism / Q000473:pathology / Q000628:therapy*
D016207:Cytokines
Hyperbaric oxygen therapy; Inflammation; Macrophage polarization; Secondary damage; Spinal cord injury