"Three Methods and Three Points" regulates p38 mitogen-activated protein kinase in the dorsal horn of the spinal cord in a rat model of sciatic nerve injury

Abstract

Tuina is a traditional Chinese treatment for sensory disturbances caused by peripheral nerve injury and related diseases. Our previous studies showed that tuina regulates relevant regions and indices of the spinal dorsal horn using the Dian, Bo, and Rou method in Yinmen (BL37), Yanglingquan (GB34), and Weizhong (BL40). Treatment prevents muscle atrophy, protects spinal cord neurons, and promotes sciatic nerve repair. The mechanisms of action of tuina for treating peripheral nerve injury remain poorly understood. This study established rat models of sciatic nerve injury using the crushing method. Rats received Chinese tuina in accordance with the principle of "Three Methods and Three Points," once daily for 20 days. Tuina intervention reduced paw withdrawal latency and improved wet weight of the gastrocnemius muscle, as well as promoting morphological recovery of sciatic nerve fibers, Schwann cells, and axons. The protein expression levels of phospho-p38 mitogen-activated protein kinase, tumor necrosis factor-α, and interleukin-1β also decreased. These findings indicate that "Three Methods and Three Points" promoted morphological recovery and improved behavior of rats with peripheral nerve injury.

Keywords: Three Methods and Three Points; dorsal horn of the spinal cord; interleukin-1β; nerve regeneration; neural regeneration; phospho-p38 mitogen-activated protein kinase; sciatic nerve injury; tuina; tumor necrosis factor-α.

Figure 1

Tuina manipulation emulator.

Figure 2

Effects of tuina treatment on the solar-thermal pain threshold in a rat model of sciatic nerve injury. The solar-thermal pain threshold was expressed as paw withdrawal latency. Data are expressed as the mean ± SEM (n = 8; one-way analysis of variance and post hoc least significant difference test). **P < 0.01, vs. sham-operated group; ##P < 0.01, vs. model group; §P < 0.05, vs. model control group.

Figure 3

Effects of tuina treatment on the recovery rate of wet weight of gastrocnemius muscle in a rat model of sciatic nerve injury. The recovery rate of muscle wet weight is defined by muscle weight on the experimental side divided by muscle weight on the control side. Data are expressed as the mean ± SEM (n = 8; one-way analysis of variance and post hoc least significant difference test). **P < 0.01, vs. sham-operated group; ##P < 0.01, vs. model group; §P < 0.05, vs. model control group.

Figure 4

Effects of tuina treatment on morphology of injured sciatic nerves of rats at 7 days and 27 days after sciatic nerve injury (hematoxylin-eosin staining, × 400). Arrows show the myelin sheath and axon. Scale bars: 100 μm.

Figure 5

Effects of tuina treatment on p-p38MAPK in the dorsal horn of the spinal cord in a rat model of sciatic nerve injury. (A, B) Western blots of p-p38MAPK on day 0 (A) and day 20 (B). (C) Quantification of p-p38MAPK protein expressions (western blot assay). The p-p38MAPK protein expressions were expressed as a ratio of integrated optical density to β-actin. Data are expressed as the mean ± SEM (n = 4; one-way analysis of variance and post hoc least significant difference test). *P < 0.05, vs. sham-operated group; ##P < 0.01, vs. model group; §§P < 0.01, vs. model control group. p38MAPK: p38 mitogen activated protein kinase; p-p38MAPK: phospho-p38MAPK.

Figure 6

Effects of tuina treatment on TNF-α (A) and IL-1β (B) in the spinal cord of rats with injured sciatic nerves (enzyme-linked immunosorbent assay). Data are expressed as the mean ± SEM (n = 4; one-way analysis of variance and post hoc least significant difference test). **P < 0.01, vs. sham-operated group; ##P < 0.01, vs. model group; §§P < 0.01, vs. model control group. TNF-α: Tumor necrosis factor-α; IL-1β: interleukin-1β.