Massage protects skeletal muscle from injury during long-term heavy-duty exercise via integrin β1 and laminin 2 channels of basement membrane

Abstract

Background: Massage is widely used in exercise-induced skeletal muscle damage (EIMD). It has been proven that massage can improve the morphology and function of damaged skeletal muscle in multiple ways. However, whether massage can protect skeletal muscles from injury during long-term heavy-duty exercise has not yet been determined.

Methods: In this study, a rat model of overuse injury was established by eccentric running for 4 weeks, and pressing at constant pressure and frequency and massage were used as intervention methods to explore whether massage could protect skeletal muscle from injury through upregulating integrin and the basement membrane laminin.

Results: The results showed that compared with the model group, the ultrastructure of skeletal muscle in the massage group was relatively complete and clear, and the maximum isotonic and tetanic contraction forces were significantly increased (P < 0.01). In addition, in the massage group, β1 integrin expression was significantly increased, p-FAK protein expression was decreased, and the co-localization of β1 integrin and the basement membrane laminin 2 was significantly increased (P < 0.01).

Conclusion: Our study shows that during long-term heavy-duty exercise, massage can enhance the cell adhesion function mediated by integrin β1 and laminin 2 to protect skeletal muscle from injury and prevent the occurrence of overuse injury.

Keywords: Laminin 2; Long-term heavy exercise; Massage; Overuse injury; Skeletal muscle; α7β1 integrin.

Fig. 1

Quantification and monitoring of massage parameters

Fig. 2

Maximum single contraction force and tetanic force of the medial head of the gastrocnemius muscle in rats. (A) Maximum single contraction force. (B) Maximum forced contraction force. C, control group; M, long-term heavy-duty exercise group; G, long-term heavy-duty exercise + sham massage group; T, long-term heavy-duty exercise + massage group. ***P < 0.001

Fig. 3

Changes in ultrastructure of the gastrocnemius muscle

Fig. 4

Protein expression in the gastrocnemius muscle of rats. The FAK, p-FAK, β-actin experiments were conducted under the same conditions as each other, and the integrin α7, integrin β1, and ATPase experiments were also conducted under the same conditions as each other. C, control group; M, long-term heavy-duty exercise group; G, long-term heavy-duty exercise + sham massage group; T, long-term heavy-duty exercise + massage group. *P < 0.05, ***P < 0.001

Fig. 5

Relative mRNA expression in gastrocnemius muscle tissue of rats. C, control group; M, long-term heavy-duty exercise group; G, long-term heavy-duty exercise + sham massage group; T, long-term heavy-duty exercise + massage group. *P < 0.05, **P < 0.01, ***P < 0.001

Fig. 6

Immunofluorescence staining