Gold nanoclusters conjugated berberine reduce inflammation and alleviate neuronal apoptosis by mediating M2 polarization for spinal cord injury repair

Zipeng Zhou; Dan Li; Xiangyi Fan; Yajiang Yuan; Hongyu Wang; Dahao Wang; Xifan Mei

doi:10.1093/rb/rbab072

Gold nanoclusters conjugated berberine reduce inflammation and alleviate neuronal apoptosis by mediating M2 polarization for spinal cord injury repair

Regen Biomater. 2021 Dec 2:9:rbab072. doi: 10.1093/rb/rbab072. eCollection 2022.

Authors

Zipeng Zhou^{1

2}, Dan Li³, Xiangyi Fan⁴, Yajiang Yuan², Hongyu Wang², Dahao Wang², Xifan Mei^{2

5}

Affiliations

¹ Department of The First Clinical College, Liaoning University of Traditional Chinese Medicine, No. 79, Chongshan East Road, Huanggu District, Shenyang City, Liaoning Province 110847, P.R. China.
² Department of Orthopedics, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China.
³ Department of Basic Science, Jinzhou Medical University, Jinzhou, China.
⁴ Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Jinzhou Medical University, Jinzhou, China.
⁵ Jinzhou Medical University, No.40, Section 3, Songpo Road, Linghe District Jinzhou City, Liaoning Province 121001, P.R.China.

Abstract

Spinal cord injury (SCI) leads to nerve cell apoptosis and loss of motor function. Herein, excessive activation of the M1 phenotype macrophages/microglia is found to be the main reason for the poor prognosis of SCI, but the selective activation phenotype (M2) macrophages/microglia facilitates the recovery of SCI. Thereafter, we used gold nanoclusters loaded berberine (BRB-AuNCs) to reduce inflammation by inhibiting the activation of M1 phenotype macrophages/microglia, which simultaneously inhibited neuronal apoptosis after SCI. In vitro and in vivo experiments showed that BRB-AuNCs reduced M1 protein marker CD86, increased M2 protein marker CD206, reduced inflammation and apoptotic cytokines (IL-1β, IL-6, TNF-α, Cleaved Caspase-3 and Bax). These results indicate that BRB-AuNCs have excellent anti-inflammatory and anti-apoptotic effects by inducing the polarization of macrophages/microglia from M1 phenotype to M2 phenotype. Thereafter, the motor functions of SCI rats were significantly improved after treatment with BRB-AuNCs. This work not only provides a new way for the treatment of SCI but also broadens BRB utilization strategies.

Keywords: berberine; gold nanoclusters; macrophages/microglia; spinal cord injury.