| Objective: To observe the effects of rolling manipulation on inflammation,fibrosis,and TGF-β1/Smad pathway protein expression in acute blunt contusion of the quadriceps muscle in rabbits,thereby revealing the underlying mechanism for its amelioration of blunt contusion of skeletal muscle.Methods: A total of 15 New Zealand White Rabbits were randomly divided into a blank group,a model group,and rolling manipulation(n=5 in each gro up).The acute blunt contusion model was established by using an 850 g homemade gravity hammer free falling hitting at the quadriceps muscle of the right leg(height 40 cm).On day 7 after successful molding,In the rolling group,the rabbits were first tied and then treated with a homemade rolling massager(Patent No.: ZL 2021 2 2808068.0,Authorized Publication No.: CN216365872 U)on their quadriceps injury;in the blank and model groups,the rabbits were simply tied;all interventions were performed once in the morning and once in the afternoon,3 min/time,for 3 days.A sampling of the quadriceps muscle was performed 24 hours after the end of the 3-day intervention.Histomorphological changes in the injured quadriceps muscle,such as inflammation and fibrosis,were observed by HE and Ma sson staining;protein expression of TGF-β1,Smad2,p-Smad2,Smad3,SphK1,S1PR3 was detected by immunoblotting.Results: In the model group,HE staining showed deformed and broken m uscle fibers,severe myocyte necrosis,blurred and incomplete muscle membranes,and vacuolated structures formed after myofibrillar lysis,with obvious inflammatory cell infiltration and a small number of nucleus-centered neonatal myofibres,but in small numbers and Masson staining reveals a large number of blue collagen fibers.In contrast,in the rolling manipulation group,inflammatory cell infiltration was significantly reduced in the HE staining compared to the model group,and a large number of nucleus-centered new myofibres and multinucleated myotubes of different sizes were visible and Masson staining showed a significant reduction in blue collagen fibers compared to the model group(P<0.01).The protein expression of TGFβ1,Smad2,p-Smad2,Smad3,SphK1,and S1PR3 in the model group was significantly increased compared to the control group(all P<0.01).And after rolling manipulation therapy,the protein expression levels of these targets were significantly reduced(P<0.01 or P<0.05).Conclusion: Rolling manipulation treatment attenuates inflammation,and fibrosis and down-regulates TGF-β1/Smad pathway protein expression in the quadriceps muscle of rabbits with an acute blunt contusion. |
