乳铁蛋白对幼年大鼠骨健康影响

目的:研究乳铁蛋白(Lactoferrin,LF)对幼年大鼠骨健康的作用。方法:将40 只4 周龄雄性SD大鼠随机分为对照组(0 mg/kg bw/d)、LF低剂量组(100 mg/kg bw/d)、LF中剂量组(500 mg/kg bw/d)和LF高剂量组(1000 mg/kg bw/d),连续喂养30 d后,测定幼年大鼠体重和脏体比变化、股骨骨密度(Bone mineral density,BMD)和骨微观结构变化、血清及股骨骨髓组织中抗酒石酸酸性磷酸酶(Tartrate resistant acid phosphatase,TRACP)、基质金属蛋白酶9(Matrix metalloproteinase 9,MMP-9)、组织蛋白酶K(Cathepsin,CTSK)、核因子κB受体激活因子配体(Receptor activator for nuclear factor-κB ligand,RANKL)和骨保护素(Osteocalcin,OPG)水平。结果:灌胃LF 30 d后,与对照组比较,LF剂量组幼年大鼠体重、脏体比增长趋势相近,差异不显著(P>0.05),LF中、高剂量组骨小梁数量(Trabecular bone number,Tb.N)、骨小梁厚度(Trabecular bone thickness,Tb.Th)、血清及股骨骨髓组织中OPG和OPG/RANKL水平显著增加(P<0.05),骨小梁分离度(Trabecular bone space,Tb.Sp)、TRACP、MMP-9、CTSK和RANKL显著降低(P<0.05)。结论:补充LF能够减少幼年大鼠骨吸收,增加骨形成和骨量,调节骨代谢平衡,促进骨健康。

Effect of Lactoferrin on Bone Health in Juvenile Rats

Objective:The effects of lactoferrin (LF) on bone health in juvenile rats were studied. Methods:Forty male Sprague-Dawley rats aged 4 weeks were randomly divided into control group (0 mg/kg bw/day), low dose LF group (100 mg/kg bw/day), LF medium dose group (500 mg/kg bw/day) and LF high-dose group (1000 mg/kg bw/day), continuous feeding for 30 days, the changes of body weight, visceral ratio, bone mineral density (BMD), bone microstructure of femur, levels of anti-tartrate acid phosphatase (TRACP), matrix metalloproteinases 9 (MMP-9) and cathepsin K (CTSK), nuclear factor kappa B receptor activating factor activating factor ligands (RANKL), osteoprotegerin (OPG) and OPG/RANKL in serum and bone marrow tissues of femurs in juvenile rats were measured. Results:After 30 days of LF gavage, compared with the control group, the increasing trend of body weight and visceral ratio of juvenile rats in LF dose group were similar that the difference was not significant (P>0.05), BMD, trabecular bone number (Tb.N), trabecular bone thickness (Tb.Th), the levels of OPG and OPG/RANKL in serum and bone marrow tissue of juvenile rats in medium and high dose group significantly increased (P<0.05), and Trabecular bone space (Tb.Sp) significantly increased, TRACP, MMP-9, CTSK and RANKL significantly decreased (P<0.05).Conclusion:Supplementation of LF can reduce bone resorption, increase bone formation and bone mass, regulate bone metabolism balance and promote bone health in juvenile rats.