Promotion Of Fracture Healing By Conjugated Linoleic Acid In Rats

Objcective: Examine the effect of Conjugated Linoleic Acid(CLA) in fracture healing in rats.Methods: 30 female Sprague-Dawley rats of 200 g in weight were randomly divided into two equal groups: CLA intervention(A) and Control(B),and fracture were created in the middle shaft of tibia on each rat. Group A had CLA(10g/Kg·diet) intragastric administration,and Group B had saline.This study quantified CLA effect in fracture healing in rats using Alkaline phosphatase(ALP),combined structural evaluation(x-ray,scoring and micro-CT), biomechanical test(3-point bending test) and histological examination.Result: 1. The level of ALP had significant difference between two groups at week 2(P<0.01).2. Radiographic evaluation showed the CLA group had vague fracture line at week 4with increased callus in volume and numbers. The fracture scoring was significant different at week 6.3. The micro-CT images indicated that at week 4, both groups had no significant difference in CSA(p=0.15), BMD(p=0.69) and BSI(p=0.06). However, at week 6, the CLA group had 14.05±3.13 mm2 in CSA, 0.98±0.04 mg/mm3 in BMD and 13.73±2.67mg/mm in BSI, which were significantly greater than the control(9.38±1.87 mm2 in CSA,p=0.02, 0.86±0.78 mg/mm3 in BMD, p= 0.02, and 8.07±1.66 mg/mm in BSI, p= 0.002).4. The 3-point bending test indicated that the load to failure of the CLA and the control groups was 78.12±10.03 N and 32.34±8.99 N, respectively. The difference was statistically significant(p=0.03).5. In the 6th week of fracture healing, CLA group is full of a lot of osteoid callus Center formed prepared bone, bony callus formed bone around the bridge complete, callus began sculpting;Callus Control group only a small proportion of hypertrophicchondrocytes, callus cartilaginous ossification distinct, full of lots of osteoid, forming prepared bone, bony callus edge bony bridge formation.Conclusion:1. CLA can significantly increase ALP activities,indicating active osteoblasts and increases the number of mineralized nodules cell maturation process. DR was equally straightforward description CLA in promoting fracture healing.2. CLA may improve the quality of fracture healing in rats callus, further improve fracture healing strength, and promote fracture healing.