DHA藻油脂质体对小鼠免疫功能调节作用研究

Effect of DHA algae oil liposomes on mouse immune function

目的研究脂质体对二十二碳六稀酸(docose hexaenoie acid,DHA)在肠上皮细胞中转运、吸收的特性并观察其对小鼠免疫功能的作用。方法采用Caco-2细胞模型测定脂质体对DHA在肠细胞摄取、表观渗透系数(apparent permeability coefficients,Papp)的影响,高效液相色谱法(high performance liquid chromatography,HPLC)测定DHA含量。KM小鼠体内实验中,将KM小鼠按照体重随机分为4组,即空白对照组、DHA藻油组(200 mg/kg)和DHA藻油脂质体组(50,200 mg/kg),观察其对免疫功能的作用。结果制备的DHA藻油脂质体包埋率为98.16%,DHA藻油和DHA藻油脂质体质量浓度在25-200 μg/mL对Caco-2细胞无明显毒性作用。DHA藻油和DHA藻油脂质体的表观渗透系数[顶侧(apical,AP)→基底侧(basolateral,BL)]值均大于1×10^(-6) cm/s,且药物外排率(efflux ratio,ER)小于2。DHA 藻油(200 mg/kg)、DHA 藻油脂质体(50 mg/kg)和DHA藻油脂质体(200 mg/kg)对小鼠的体重无明显的影响(P>0.05);与空白对照组比较,DHA藻油和DHA藻油脂质体能够显著增加溶血空斑数、溶血素水平、吞噬指数、免疫器官系数(P<0.05或P<0.01),且对小鼠单核巨噬细胞的吞噬能力有显著的增强作用(P<0.05或P<0.01);此外,与空白对照组比较,DHA藻油(200 mg/kg)、DHA藻油脂质体(50,200 mg/kg)还能显著增强KM小鼠自然杀伤细胞(natural killer cell,NK)活性(P<0.05或P<0.01)。结论 DHA藻油和DHA藻油脂质体在肠细胞中的跨膜吸收以被动扩散为主,脂质化后能够显著增强DHA的生物利用度,DHA藻油脂质体具备与DHA藻油相似的免疫调节作用,且DHA藻油脂质体对小鼠免疫功能的作用最为显著。

Objective To study the transport and absorption of docose hexaenoie acid(DHA)in intestinal epithelial cells and observe its effect on immune function of mice.Methods A Caco-2 cell model was applied to detect the effect of DHA algae oil liposomes on intestinal cell uptake,apparent permeability coefficients(Papp)and high performance liquid chromatography(HPLC)were used to detect the concentration of DHA.Subsequently,KM mice randomly divided into 4 groups according to body weight,the control group,DHA algae oil group(200 mg/kg)and DHA algae oil liposomes groups(50,200 mg/kg).After immunology related indicators were performed to analyze the effect of DHA algae oil liposomes on immune function.Results The encapsulation efficiency of DHA algae oil liposomes was 98.16%.There was no significant toxic effect on Caco-2 cells in the range of 25‒200μg/mL after DHA algae oil and DHA algae oil liposomes treatment.The Papp[apical(AP)→basolateral(BL)]ratios of DHA algae oil and DHA algae oil liposomes were greater than 1×10^(-6) cm/s,and the efflux ratio(ER)was less than 2.There was no significant change in body weight of KM mice after treatment with DHA algae oil and DHA algae oil liposomes as compared to the control group(P>0.05).Meanwhile,DHA algae oil(200 mg/kg),DHA algae oil liposomes(50 mg/kg)and DHA algae oil liposomes(200 mg/kg)treatment could significantly increase hemolytic plaque number,hemolysin level,phagocytosis index,immune organ coefficients(P<0.05 or P<0.01),as well as enhance the phagocytosis of mononuclear macrophage activity in KM mice(P<0.05 or P<0.01).In addition,treatment with DHA algae oil(200 mg/kg),DHA algae oil liposomes(50,200 mg/kg)could also significantly enhance the activity of natural killer cells(NK)in KM mice when compared with the control group(P<0.05 or P<0.01).Conclusion The transmembrane transport pathway of DHA algae oil and DHA algae oil liposomes are mainly passive diffusion,and lipidization can significantly improve the bioavailability of DHA algae oil.In addition,DHA algae oil liposome has a similar immunomodulatory effect to DHA algae oil,but its dose is significantly lower than that of DHA algal oil.