目的 观察丹蛭降糖胶囊(DJC)对db/db小鼠摄食行为及脑摄食中枢α-MSH、AgRP的调节作用.方法 db/db组和DJC组各9只db/db小鼠,db/dm组共9只db/dm小鼠,DJC组灌胃DJC混悬液每只630 mg·kg-1·d-1,db/db组和db/dm组灌胃等量纯净水,饲养12周.每周检测体质量及食物消耗量;Elisa法检测血清α-MSH、AGRP含量,下丘脑α-MSH、AGRP蛋白含量;qRT-PCR法检测下丘脑α-MSH、AGRP mRNA含量;HE染色观察病理改变;免疫组化法观察下丘脑α-MSH、AGRP表达.结果 相较db/dm组,db/db组血清α-MSH、下丘脑α-MSH蛋白、mRNA及免疫组化α-MSH均明显减少(P<0.001),而血清AgRP,下丘脑AgRP蛋白、mRNA及免疫组化AgRP均明显增多(P<0.01,P<0.001);db/db组的体质量及摄食量较db/dm组全饲养周期均明显增高(P<0.001);相较db/db组,DJC组血清α-MSH、下丘脑α-MSH蛋白、mRNA及免疫组化均明显升高(P<0.001),而血清AgRP、下丘脑AgRP蛋白、mRNA及免疫组化均明显减少(P<0.01,P<0.001);DJC组体质量从第8周开始较db/db组明显减轻(P<0.05,P<0.01,P<0.001),摄食量全饲养周期均明显低于db/db组(P<0.05,P<0.01,P<0.001).结论 丹蛭降糖胶囊能够能够通过提高db/db小鼠血清α-MSH、下丘脑α-MSH蛋白、mRNA的含量,减少血清AgRP、下丘脑AgRP蛋白、mRNA的含量,起到改善db/db小鼠的摄食行为,减少摄食量,减轻小鼠体重等作用.
Objective To observe Danzhi Jiangtang capsule(DJC)on feeding behavior and alpha-melanocyte stimulating hormone(α-MSH)and agouti-related protein(AgRP)in the brain feeding center of db/db mice.Methods 18 SPF grade male db/db mice and 9 SPF grade db/dm mice were selected.When the fasting blood glucose of db/db mice was≥11.1 mmol·L-1,18 db/db mice were divided into db/db group and DJC group,while the other 9 db/dm mice were as the db/dm group.Each mouse in the DJC group was gavaged with 630 mg·kg-1·d-1 of DJC suspension,and the db/db group and db/dm group were gavaged with the equal amount of purified water,and were reared for 12 weeks.Body mass and food consumption were detected weekly;The levels of serum α-MSH and AgRP,and hypothalamic α-MSH and AgRP protein were detected by Elisa assay;The levels of hypothalamic α-MSH and AgRP mRNA were detected by qRT-PCR assay;HE staining was used to observe pathological changes;And immunohistochemical assay was used to observe the expression of hypothalamic α-MSH and AgRP.Results Compared with the db/dm group,the levels of serum α-MSH,hypothalamic α-MSH protein,mRNA and immunohistochemical α-MSH were significantly reduced in the db/db group(P<0.001),whereas the levels of serum AgRP,hypothalamic AgRP protein,mRNA and immunohistochemical AgRP were significantly increased(P<0.01 and P<0.001);The body mass and feed intake of the db/db group were significantly higher than those of the db/dm group throughout the feeding cycle(P<0.001);Compared with the db/db group,the levels of serum α-MSH,hypothalamic α-MSH protein,mRNA and immunohistochemistry in the DJC group were significantly increased(P<0.001),whereas the levels of serum AgRP,hypothalamic AgRP protein,mRNA and immunohistochemistry were significantly decreased(P<0.01,P<0.001);In the DJC group body mass was significantly reduced from week 8 compared with the db/db group(P<0.05,P<0.01,P<0.001),and food intake throughout the feeding cycle was significantly lower than that in the db/db group(P<0.05,P<0.01,P<0.001).Conclusion By increasing the levels of serum α-MSH and hypothalamic α-MSH protein,mRNA,and decreasing the content of serum AgRP and hypothalamic AgRP protein,mRNA,DJC can improve feeding behavior,reduce food intake,and reduce body weight in db/db mice.