The effect of propolis implantation on skeletal muscle atrophy in peripheral nerve injury

Background and Aim : Peripheral nerve injuries are widespread in trauma happenings. Nerve injuries are important because it can cause lifelong disabilities. One of the complications of nerve injuries is atrophy of the skeletal muscles innervated by the injured nerve. Skeletal muscle atrophy can affect the quality of life. Moreover it is associated with increased invalidism and life expectancy. Currently there is no proper treatment for muscle atrophy, just exercise and protein supplements. Propolis is a natural resinous product of honeybees from parts of plants such as buds and exudates. Propolis has pleasant smell because of aromatic compounds. It varies in color from yellow, green too red and dark brown depending on its origin and age. It has been used in folk medicine for its special properties such as anti-bacterial, anti-inflammatory, anti-oxidant, angiogenesis, anti-tumor, anti-fungal and etc. The present study is to investigate the effect of natural product of honeybees named propolis, against gastrocnemius muscle in the nerve injury conditions.Methods : 24 adult male rats were randomly divided into 3 groups as sham surgery, control group and propolis group. After routine preparation, under general anesthesia, left sciatic nerve was exposed. Next, 10mm nerve segment was cut and then sutured the distal and proximal stump of nerve with 8-0 nylon in both propolis and control groups. Then put a piece of sterilized raw brown propolis at the suture places in propolis group. In the sham group just exposed the sciatic nerve. Finally in all groups the muscle and the skin were sutured with 4-0 nylon. 30 and 90 days after surgery, all animals were evaluated by wet muscle weight and muscle fiber diameter with H&E staining.Results : On day 30 after surgery, the mean of muscle fiber diameters was greater in propolis (40.11±2.7μm) than control (27.46±3.2μm) groups. The difference between them was statistically significant (p<0.01). The mean of wet muscle weight in propolis (1.408±0.21g) was greater than control (0.87±0.14g) groups (p<0.01). The mean of wet muscle weight in sham group (1.76±0.23g) was greater than other groups. But the difference between sham and propolis group was not statistically significant (p> 0.05). On day 90 post operation the mean of muscle fiber diameters was greater in propolis (46.12±3.2μm) than control (36.48±2.5μm) groups (p<0.02). The mean of muscle fiber diameter in sham group (50.49±2.4μm) was greater than other groups (p<0.05). The mean of wet muscle weight in propolis (1.623±0.14g) was greater than control (1.18±0.2g) groups. The mean of wet muscle weight in sham group (1.78±0.16g) was greater than both propolis and control groups. But the difference between sham and propolis group was not statistically significant (p> 0.05).Conclusion : These findings demonstrate that propolis can decrease skeletal muscles atrophy following nerve injury.

کلیدواژه ها:

Propolis ، Muscle atrophy ، Peripheral nerve ، Rat