Effect of flaxseed application on bone healing in male rats, histological and immunohistochemical evaluation of vascular endothelial growth factor

Abstract

Background and Objectives: Bone repair is a multistep process that involves migration, proliferation, differentiation and the activation of several cell types. Bone is a highly vascularised tissue that is reliant on the close spatial and temporal connection between the blood vessels and bone cells to maintain skeletal integrity. Therefore, angiogenesis plays a pivotal role in skeletal development and bone fracture repair. In this study, the role of angiogenic and osteogenic factors in the adaptive response and interaction of osteoblasts and endothelial cells during the multistep process of bone development and repair have been highlighted. Furthermore, the role of the local exogenous application of flaxseed in bone healing was identified and the immunohistochemical expression of VEGF in a rat model of bone defects was analyzed. Materials and Methods: Twenty-one male rats, weighing 350-400 g, were subjected to a surgical operation of the medial sides of both tibiae bones (the right side was considered as the experimental site and the left side as the control), in the control, the bone defect was treated with a local application of 1 µL normal saline, whereas, the experimental site was treated with a local application of 1 µL flaxseed oil. Seven rats were killed at 3, 7 and 14 days after surgery and bone healing was histologically examined through the immunohistochemical localization of VEGF. All statistical analyses were computed using GraphPad Prism version-5. Results: Bone defects treated with the local application of flaxseed showed early osteoid tissue deposition with high cell counts of osteoblasts, osteocytes and osteoclasts. Immunohistochemical staining for VEGF in stromal cells revealed a higher expression in the flaxseed group in comparison with the control. Conclusion: The low dose application of flaxseed could be an effective therapeutic treatment for bone injuries. These data indicate the possibility of future clinical applications for flaxseed.