ABSTRACT
OBJECTIVE@#To observe the effects of electroacupuncture (EA) on denervated skeletal muscle atrophy and expression of IGF-1/PI3K/AKT signaling pathway in rats, and to explore the possible mechanisms of it.@*METHODS@#Thirty-six male SD rats were randomly divided into a control group, a model group and an EA group. Denervated muscle atrophy model was made by cutting off the left hindlimb sciatic nerve in the model group and the EA group. In the EA group, EA, dense-disperse wave, 2 Hz/33 Hz and 1.5-2 mA, was connected at "Zusanli" (ST 36) and "Shangjuxu" (ST 37). The treatment was given for 30 min every time, once a day and a total of 20 times were needed, there was 2 days interval every 5 times. The rats in the control group and model group were fixed in the same cage every day but not applied EA. Sciatic nerve function index (SFI) and ratio of muscle wet weight (RWW) were measured after treatment. HE staining was used to determine the ratio of cross-sectional area (RCA) and the ratio of fiber diameter (RFD). TUNEL and double immunofluorescence staining were used to evaluate the myocyte apoptosis, proliferation and differentiation. The mRNA expressions of IGF-1 and AKT were detected by real-time PCR. The total protein of AKT, p-AKT (Ser473) and p-AKT (Thr308) were detected by western blot.@*RESULTS@#Compared with the control group, SFI, RWW, RCA and RFD of the model group were significantly decreased and apoptotic index of myocytes were significantly increased (all <0.01). Compared with the model group, the above indexes of the EA group were improved (all <0.05), and the expressions of PAX3 and PAX7 related to proliferation and differentiation of muscle satellite cells were significantly increased (both <0.01), p-AKT (Ser473) protein level was increased (<0.05).@*CONCLUSION@#EA can improve the atrophy of denervated muscles, reduce myocyte apoptosis, and promote the proliferation and differentiation of muscle satellite cells. The mechanism may be related to the increase of p-AKT (Ser473) level and activation of AKT signaling pathway.
Subject(s)
Animals , Male , Rats , Acupuncture Points , Electroacupuncture , Insulin-Like Growth Factor I , Muscle, Skeletal , Muscular Atrophy , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Rats, Sprague-DawleyABSTRACT
Objective To sift out the optimized electric pulse parameters for electroacupuncture treatment for lower limb myatrophy and explore the mechanism of its treatment.Method A model of lower limb myatrophy was made in 40 SD rats.The rats were then randomized to groups A (model group without electroacupuncture), B (a pulse duration of 0.5 ms and a frequency of 2 Hz), C (a pulse duration of 200 msand a frequency of 2 Hz) and D (a pulse duration of 200 ms and a frequency of 1/2/3 Hz).Points Zusanli(ST36)and Chengshan(BL57)were given electroacupuncture for four courses of treatment.Thesciaticfunction index (SFI),gastrocnemius muscle wet weight ratio (GW), gastrocnemius muscle fiber cross-sectional area ratio (GC),gastrocnemius muscle cell diameter ratio (GD)and gastrocnemius muscle cell apoptosis index (AI)were determined.Result SFI, GW and GC increased significantly and AI decreased significantly in groups C and D compared with group A (P<0.05). AI decreased significantly in groups C and D compared with group B (P<0.05). AI decreased significantly in groups D compared with group C (P<0.05). Conclusion Apulse duration of 200 ms and a frequency of 1/2/3 Hz are the optimizedelectric pulse parametersfor electroacupuncture delaying myatrophy.Its mechanism is related to inhibiting myocyte apoptosis.
ABSTRACT
Objective To sift and optimize pulse width for electroacupuncture prevention and treatment of muscular atrophy. Method A model of lower limb muscle atrophy was made in 40 rats. They were randomized into groupsⅠ (no electroacupuncture),Ⅱ (a pulse width of 0.5 ms and a frequency of 2 Hz), Ⅲ (a pulse width of 100 ms and a frequency of 2 Hz) and Ⅳ (a pulse width of 200 ms and a frequency of 2 Hz). Points Zusanli (ST36) and Chengshan(BL57) were given electroacupuncture. Sciatic function index (SFI), gastrocnemius muscle wet weight ratio (GW), the cross-sectional area of gastrocnemius muscle fibers (GC), gastrocnemius muscle cell diameter (GD) and gastrocnemius muscle cell apoptosis index (AI) were used as indicators of therapeutic effect. Result Compared with group Ⅰ, SFI and GW increased significantly in groups Ⅲ and Ⅳ (P<0.05). Compared with groupsⅠ and Ⅱ, AI on the affected side decreased significantly in groups Ⅲ and Ⅳ (P<0.05). Conclusion The therapeutic effect of electroacupuncture is related to its pulse width. The pulse widths of 100 ms and 200 ms are significantly more effective than a pulse width of 0.5 ms from a conventional electroacupuncture device in preventing and treating muscular atrophy.