不同叶酸、维生素B_6摄入水平对模拟失重大鼠同型半胱氨酸代谢的影响

目的观察模拟失重条件下大鼠血清叶酸、维生素B6以及同型半胱氨酸(Hcy)代谢变化情况和不同叶酸、维生素B6摄入水平对Hcy代谢的影响。方法本实验采用大鼠尾部悬吊模型,将SD雄性大鼠按体重随机分为地面对照组、尾吊对照组及尾吊营养素干预组(按正交设计的方法分为9组),总共11组,对照组和尾吊营养干预组经人工灌胃的方式分别给于对应剂量的纯净水和维生素混合溶液,饲养4w后断头取血分离血清,按试剂盒方法测定其相关各项生化指标。结果尾吊对照组的血清叶酸、维生素B6水平低于地面对照组,而Hcy水平有增高的趋势;尾吊营养干预组的血清Hcy水平均低于尾吊对照组,血清叶酸、维生素B6水平均高于尾吊对照组,并且随着叶酸、维生素B6摄入的增加,血清Hcy水平有递减的趋势,正交结果分析显示剂量水平在H1组(叶酸高剂量水平和维生素B6低剂量水平)时,降低血清Hcy水平效果最佳。尾吊对照组的血清超氧化物歧化酶(SOD)活力显著高于其他各组(P<0.05),谷胱甘肽过氧化物酶(GSH-Px)活力各组无显著性差异。尾吊对照组血清血栓素A2(TXA2)水平显著增加(P<0.05)以及血清前列环素(PGI2)水平显著降低(P<0.05)。结论在尾吊条件下,实验4 w后大鼠体内叶酸、维生素B6水平降低,Hcy水平有升高的趋势;补充叶酸、维生素B6可以有效增加大鼠血清叶酸、维生素B6水平,降低血清Hcy水平,并且采用H1组剂量时效果最佳;补充叶酸、维生素B6可以通过调节Hcy的代谢,减少体内过氧化产物的形成,调节了PGI2与TXA2的水平,从而减小Hcy升高带来的消极影响。

EFFECTS OF DIFFERENT INTAKES OF FOLATE AND VITAMIN B6 ON HOMOCYSTEINE METABOLISM IN WEIGHTLESSNESS-SIMULATED RATS

Objective To observe the effects of different intakes of folate(FA) and vitamin B6(VB6) on homocysteine(Hcy) metabolism in the hindlimb suspended rats.Method The hindlimb suspended model was induced in 110 male SD rats and randomly divided into 11 groups: ground control group(GC),hindlimb suspended control group(HC) and nutrition intervention hindlimb suspended groups(NS) which were again divided into nine groups(L1,L2,L3,M1,M2,M3,H1,H2,H3) by orthogonal design mothod.They were fed normal diets and administered i.g.with water or vitamins solution.The biochemical indices of serum were measured after 4 w.Results After experiment,the serum FA and VB6 in HC group were lower than those in GC group,but serum Hcy higher.The serum Hcy in NS group was lower than that in HC group,but FA and VB6 all higher.In addition,when the intakes of FA and VB6 were increased,the serum Hcy was decreased.By orthogonal analysis,when the dose of FA intakes was at the highest level and VB6 intakes at the lowest level,the decrease of serum Hcy was the best.While serum superoxide dismutase(SOD) activities in HC group were higher than those in other groups(P<0.05),while serum glutathione peroxidase(GSH-Px) activities were not significantly different.The serum thromboxane A2(TXA2) in HC group was significantly higher than that in other groups(P<0.05),but the serum prostaglandin 2(PGI2) was in another way(P<0.05).Conclusion Serum FA and VB6 were decreased and serum Hcy increased in rats under weight-less condition.However,intragastric administration of FA and VB6 might effectively reverse these changes,decrease the peroxides in body,and lessen the negative effects induced by hyperhomocysteinemia.The level of serum PGI2 and TXA2 was also adjusted by supplement of FA and VB6.The dosage of FA and VB6 intakes in H1 group was preferable.