Abstract
The key target and regulatory mechanism of electroacupuncture of Zusanli (ST36) on extensor longus muscle injury in a jumping rat model were investigated. To this end, 24 female SD rats were randomly divided into the following four groups: no-treatment control group (NON), 6-week jumping group (J6O), electroacupuncture group after 6-week jumping (J6A), and natural recovery group after 6-week jumping (J6N). After 6 weeks of jumping, in the electroacupuncture group (J6A), electroacupuncture stimulation was applied at Zusanli(ST36) for 20 min per day over the course of 5 days. In the natural recovery group (J6N), rats were fastened with a special apparatus without electroacupuncture stimulation for 20 min at the same time. Transmission electron microscopy, transcriptome sequencing and analysis, Western blotting assay and immunofluorescence staining were performed at the end of our experiment. The recovery effect of J6A rats was more obvious than that of J6N rats and J6O rats as indicated by changes of infiltration of inflammatory cells and morphological structure. Notably, the morphological structure of J6A rats was closer to NON rats in the observation of transmission electron microscopy. CISH/STAT3 regulation was identified by mRNA-seq. The pro-inflammatory response to STAT3 activation was alleviated through up-regulating the expression of CISH protein in J6A rats relative to J6O rats. The level of BAX was decreased and the level of Bcl-2 level was increased in J6A rats relative to J6O rats. Moreover, when compared to J6N rats, the level of Bcl-2 was significantly up-regulated in J6A rats. Increased caspase-3 expression but decreased CDKN2α expression was shown in J6A rats relative to NON rats. These results indicate that the potential mechanism underlying electroacupuncture stimulation of Zusanli (ST36) in repairing the injured extensor digitorum longus following overused jumping may be attributed to CISH/STAT3 regulation of proteins associated with inflammation, apoptosis, and proliferation.
Highlights
Muscle fatigue due to reduced muscle shock absorption is the main cause of sports injuries
Electron microscopic observation of the extensor digitorum longus in NON rats showed normal membrane and myofibrillar architecture, including neatly aligned muscle fibers, intact Z-lines, an appropriate number of extracellular matrix collagen fibers evenly distributed around the myocytes, and small intercellular collagen area (Figure 2A)
Acupuncture has been used in China for thousands of years, and the clinical effect of acupuncture or electroacupuncture stimulation on the inhibition of persistent pain such as inflammatory pain, neuropathic pain, visceral pain, and cancer-related pain has been supported by relevant scientific evidence [12,13,14,15,16]
Summary
Muscle fatigue due to reduced muscle shock absorption is the main cause of sports injuries. Overuse of the lower extremities resulted in lower leg injury rates of 9.0% to. 32.2%, and the incidence of injuries around the foot ranged from 5.7 to 39.3% [1]. Muscle fatigue combined with repetitive motion loads during long-distance running and repetitive jumping movements can lead to fatigue of the dorsiflexors and plantar flexors of the ankle joint. The Mizrahi study [2] found that the mean integrated electromyographic signal (iEMG) of the anterior tibia was significantly lower from the 20th minute compared to the 5th minute of running, while no significant changes were found in the iEMG of the gastrocnemius muscle, suggesting that the imbalance between muscles may increase the Biomedicines 2021, 9, 1849.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
