Lactoferrin Application for the Prevention and Restoration of Bone Tissue Alterations during Hindlimb Unloading in Rats

The effect of gravitational unloading (antiorthostatic hindlimbsuspension) and subsequent recovery on the mineral density and mechanicalproperties of the femoral and tibial bones in Wistar rats was studiedduring oral administration of a human lactoferrin (LF) biotechnologicalanalog (200 mg/kg) derived from the milk of producer goats. Bonemineral density was determined by dual energy X-ray absorptiometry,while bone strength and stiffness were assessed via the three-pointbending test. It was shown that 21-day gravitational unloading ledto a decrease in the mineral density of the tibia and femur. OralLF administration had no significant effect on the mineral densityand projected area of the bones. There were no statistically significantdifferences in mechanical stiffness between the experimental groups,although after readaptation, the ultimate strength was significantlyhigher in LF-administered groups. Thus, the results may indicatethe potential of LF preparations as prophylactic agents for maintainingbone strength. At the same time, the maintaining of bone mineraldensity under deficit-stimulating conditions requires a considerationof alternative dosages and drug delivery methods.