Abstract
Background: During early phases of life, epigenetic factors interfere with normal growth of the individual and induce morphological and functional alterations. The aim of this study was to analyze the effects of pre and postnatal food restriction in rats, on the microstructure and mechanical properties of the rat femur bone.
Methods: Food restricted male rats were from pregnant mothers maintained under daily-restricted diet pre and postnatal periods. After waning, the rats were maintained with access to milk only for 12 h until weaning. The control rats were from normal pregnant mothers feeding with free access to food and water during experimental period. Animals were sacrificed at 6 and 9 weeks of age; with femur bone submitted to 3 point bending mechanical test like indicators of biomechanical properties. After that the samples were morphometrically evaluated at electronic microscope.
Results: The restricted diet group showed reductions in the body weight, width and thickness of femur bone. Statistical analysis demonstrated significant (P<0.05) changes in the evaluated parameters, showing different values for the Young modulus, ultimate load at fracture, failure (maximum breaking load), percentage of maximum deformation displacement showed decrement compared with the control rats. The data of structural measure showed that microstructure arrangement was damaged by food scarcity. Findings showed that food restriction contributed to detrimental bone structure, particularly modifying the collagen bundle and consequently inducing bone fragility in adulthood, demonstrated by the flexural diminished values.
Conclusion: Nutritional conditions are determinants for the bone structure establishment, with effects persisting for a long-term period, remaining until adult life.
Keywords: Bone rat, breaking resistance, development, collagen fibers, food scarcity.
Graphical Abstract
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