Abstract
Background: Flaxseed oil (FO) is an alpha linolenic acid source important for growth and body development. However, there is little literature on the role of FO in critical stages of bone development and formation. Objective: This study evaluated the influence of a diet containing FO on rat femurs. Methods: After birth, mothers and pups were divided into control and flaxseed groups (n = 6 pups each) fed diets containing 7% soybean oil (C) or 7% FO. At 21 days, pups were weaned and separated from the mothers, and control or experimental diets were continued. At 67 days, the following were analyzed: osteocalcin and osteoprotegerin (OPG) levels, bone mineral density (BMD) and content, and bone area; the dimension, BMD, head radiodensity, and biomechanical proprieties of the right femur; and histomorphometric parameters of the left femur. Results: Compared to the C group, the FO group presented (p < 0.05) a lower body mass (-3.7%) and medullary area (-10.1%) and higher osteocalcin (+36.7%), OPG (+52.5%), femur width (+3.8%), absolute mass (+2.3%), femur BMD (+3.6%), head radiodensity (+6.1%), maximum force (+7.4%), breaking strength (+17.3), and cortical thickness (+7.0). Conclusion: The FO diet contributed to femur quality in healthy male Wistar rats.
Link to Full Text
Key Points
Flaxseed oil (FO) is considered a food with functional properties and represents one of the largest sources of ALA among plants (15% LA and 56% ALA). However, there is little literature about the role of FO in critical stages of bone development and formation. Thus, the purpose of this study was to evaluate the influence of a diet containing FO during lactation, childhood, and adolescence on the bone structure of Wistar male rats at 67 days of life, which is equivalent to human adolescence, a critical period for bone mass acquisition. This the first study to evaluate the body composition of young male rats with FO intake during early life. DXA revealed similar body compositions between groups. Higher osteocalcin and OPG levels were observed in the FO group than in the C group. Increased osteocalcin levels are related to bone formation, while increased OPG levels are associated with negative regulation of osteoclastogenesis, thus favoring osteoclast apoptosis and, osteoblast maintenance and contributing to bone formation. Therefore, osteocalcin and OPG levels are involved in bone formation and contributed to important factors for bone integrity in the FO group, including increases in absolute bone mass, femur width, BMD, head radiodensity, maximum strength, and breaking strength and a decreased medullary area inthe femur.
Regarding histomorphometry, the femurs of FO group rats had a significantly lower medullary area and higher cortical thickness compared to those of controls. With the findings that FO was able to increase bone density, quality, and strength, the consumption of FO by humans in critical stages of development can contribute to greater acquisition of bone mass.