胰腺癌细胞可溶性分泌物对小鼠脂代谢的影响

Effects of pancreatic cancer cell soluble secretions on lipid metabolism in mice

目的探讨胰腺癌细胞可溶性分泌物对体内脂肪代谢的影响。方法利用无血清培养基培养胰腺癌Panc-1、MiaPaCa-2、BxPC-3细胞24 h后留取上清制得胰腺癌细胞条件培养基。全实验包括两个子实验,实验A将37只BALB/c小鼠随机分为对照组(n=14),Panc-1组(n=10),MiaPaC-2组(n=6)和BxPC-3组(n=7),分别注射正常DMEM培养基和3种胰腺癌细胞(Panc-1,MiaPaCa-2,BxPC-3)条件培养基,每组小鼠连续7 d接受培养基的皮下注射,每日2次。监测每只小鼠进食量及体质量,检测血浆葡萄糖、三酰甘油含量和肝脏中糖原含量,酶联免疫吸附法(ELISA)测定血浆胰岛素水平,小鼠的腹股沟脂肪垫(BAT)、附睾脂肪垫(WAT)予以称质量,Western blot检测脂肪中脂肪甘油三酯脂肪酶(ATGL)蛋白表达水平。实验B将30只BALB/c小鼠随机分为对照组(n=10)、1/2 M组(n=10)、M组(n=10),将正常DMEM培养基和不同剂量的MiaPaCa-2细胞条件培养基注射入对应组别小鼠体内,余处理与实验A相同。结果实验A中,小鼠进食量及体质量初期均下降,之后回升并趋于稳定,与对照组相比,MiaPaCa-2组和BxPC-3组血浆胰岛素、血糖水平升高(P<0.05),肝糖原、三酰甘油水平下降(P<0.05),BAT和WAT质量增加(P<0.05),Panc-1组仅三酰甘油水平下降(P<0.05),3个胰腺癌细胞条件培养基注射组脂肪组织内ATGL表达水平均下降(P<0.05);实验B中,与对照组相比,M组血浆胰岛素和葡萄糖上升(P<0.05),肝糖原和三酰甘油均下降(P<0.05),BAT和WAT质量增加(P<0.05),ATGL表达水平下降(P<0.05),1/2 M组仅胰岛素水平和脂肪垫质量上升(P<0.05)。结论注射胰腺癌细胞条件培养基可造成小鼠体内脂肪代谢失衡,出现胰岛素抵抗、脂肪储存加强和脂肪分解减弱的现象。

Objective To observe the effects of pancreatic cancer cell soluble secretions on lipid metabolism.Methods The conditioned media of pancreatic cancer cells were derived from serum-free media culturing pancreatic cancer cells for 24 h.The whole study included 2 sub-studies.In the first one,37 BALB/c mice were randomly divided into control group(n=14),Panc-1 group(n=10),MiaPaCa-2 group(n=6)and BxPC-3 group(n=7).The normal DMEM and conditioned media of 3 pancreatic cancer cell lines(Panc-1,MiaPaCa-2 and BxPC-3)were injected into mice in the corresponding group.The mice in each group received subcutaneous injection twice a day for 7 days.Body weight and food intake of each mouse were recorded.Blood levels of glucose,triglyceride and hepatic glycogen content were detected.Plasma insulin level was detected by ELISA.Inguinal fat pad and epididymal fat pad were weighed,and the expression levels of ATGL were detected by Western blot assay.The second sub-study consisted of 30 mice and were divided into 3 groups,control group(n=10),1/2 M group(n=10)and M group(n=10).The normal DMEM and the different doses of MiaPaCa-2 cell conditioned media were injected into the corresponding groups of mice.Results In the first sub-study,the initial intake and body weight of mice decreased,and then recovered and tended to balance.Compared with the control group,the levels of plasma insulin and blood glucose increased,hepatic glycogen and triglyceride contents decreased,and the weight of BAT and WAT increased in MiaPaCa-2 group and BxPC-3 group(P<0.05),but only triglyceride contents decreased in Panc-1 group(P<0.05).The expression level of ATGL in adipose tissue was decreased in three pancreatic cancer cell media injection groups(P<0.05).In the M group of second experiment,plasma insulin and glucose increased(P<0.05),hepatic glycogen and triglyceride decreased(P<0.05),BAT and WAT weights increased(P<0.05),ATGL expression decreased(P<0.05),only insulin level and fat depot weights increased in 1/2 M group(P<0.05).Conclusion Injection of pancreatic cancer cell conditioned medium into mice can cause the dysregulation of lipid metabolism in vivo.In addition,the decreased insulin sensitivity,increased fat storage and impaired lipolysis are observed.