Early Intervention of Cold-Water Swimming on Functional Recovery and Spinal Pain Modulation Following Brachial Plexus Avulsion in Rats.

Yueh-Ling Hsieh,Chen-Chia Yang,Yu-Lin Lu,Nian-Pu Yang,Shih-Fong Chen

doi:10.3390/ijms23031178

Yueh-Ling Hsieh, Chen-Chia Yang + Show 3 more

Open Access

https://doi.org/10.3390/ijms23031178

Copy DOI

Abstract

Brachial plexus avulsion (BPA) causes peripheral nerve injury complications with motor and sensory dysfunction of the upper limb. Growing evidence has shown an active role played by cold-water swimming (CWS) in alleviating peripheral neuropathic pain and functional recovery. This study examined whether CWS could promote functional recovery and pain modulation through the reduction of neuroinflammation and microglial overactivation in dorsal horn neurons at the early-stage of BPA. After BPA surgery was performed on rats, they were assigned to CWS or sham training for 5 min twice a day for two weeks. Functional behavioral responses were tested before and after BPA surgery, and each week during training. Results after the two-week training program showed significant improvements in BPA-induced motor and sensory loss (p < 0.05), lower inflammatory cell infiltration, and vacuole formation in injured nerves among the BPA–CWS group. Moreover, BPA significantly increased the expression of SP and IBA1 in dorsal horn neurons (p < 0.05), whereas CWS prevented their overexpression in the BPA–CWS group. The present findings evidenced beneficial rehabilitative effects of CWS on functional recovery and pain modulation at early-stage BPA. The beneficial effects are partially related to inflammatory suppression and spinal modulation. The synergistic role of CWS combined with other management approaches merits further investigation.

Highlights

Brachial plexus avulsion (BPA) is considered the most severe type of injury to the upper limb
Z = −3.79, p < 0.001) and 2Wposttr (TRPM8: Z = −3.79, p < 0.001; transient receptor potential vanilloid subtype 1 (TRPV1): Z = −3.79, p < 0.001) in the BPA–cold-water swimming (CWS) group compared with the BPA–sCWS group
CWS significantly reduced substance P (SP)-LI cells and ionized calcium-binding adaptor molecule 1 (IBA1)-LI in dorsal horns, especially in Lamina I and II in the BPA–CWS group compared with the BPA–sCWS group (SP-LI: Z = −3.79, p < 0.001, Figure 3E; IBA1-LI: Z = −3.79, p < 0.001, Figure 3J)

Summary

Introduction

Brachial plexus avulsion (BPA) is considered the most severe type of injury to the upper limb. It is usually caused by high-energy trauma with a tremendous amount of stretching force and is often combined with multiple injuries of one or more roots from the spinal cord levels of C5 to T1 [1,2]. An avulsion injury triggers intense neuroinflammation at the lesion site both in the peripheral and central nervous systems; BPA has unique characteristics including motor and sensory dysfunction of the upper limb, and even total loss of these functions during the whole pathophysiological process of global avulsion [3].

Methods

Results

Discussion

Conclusion