PDF(Pubmed)
Abstract：
UNASSIGNED: To investigate the role and mechanism of trimethylamine N-oxide (TMAO), a uremic toxin, in renal fibrosis.
UNASSIGNED: A total of 20 male BALB/c mice were randomly and evenly assigned to a Control group and a TMAO group. Mice in the Control group received intraperitoneal injection of normal saline, while mice in the TMAO group received intraperitoneal injection of TMAO (20 mg/[kg·d]). The injection was given once a day for 8 weeks. Histopathology and fibrosis of kidney were observed by H&E staining and Masson staining. Immunohistochemistry was performed to determine the levels of alpha smooth muscle actin (α-SMA), recombinant human fibronectin fragment (Fibronectin), and sterol-regulatory element binding protein 1 (SREBP1). Western blot was performed to determine α-SMA, SREBP1, phosphatidylinositol 3 kinase (PI3K), phospho-phosphatidylinositol 3 kinase (p-PI3K), protein kinase B (PKB, also known as AKT), and phospho-AKT (p-AKT) protein levels. HK2 cells were treated with SREBP1 small interfering RNA (siRNA) and PI3K/AKT inhibitor, respectively, and the reversal of the effects of TMAO was examined.
UNASSIGNED: Animal experiments showed that, compared with the Control group, the mice treated with TMAO experienced pathological damage and fibrosis of the kidney tissue and the expression levels of fibrosis markers, α-SMA and Fibronectin, in the kidney were increased (all P<0.05). According to the findings from further investigation, the TMAO-treatment group showed increased expression of SREBP1 and an up-regulation of PI3K phosphorylation ratio and AKT phosphorylation ratio compared with those of the Control group (all P<0.05). Cell experiments produced results similar to those of the animal experiment. After siRNA interference with SREBP1 expression, the expression levels of fibrosis marker proteins decreased (P<0.05). Besides, the high expression of SREBP1 caused by TMAO was inhibited after HK2 cells were incubated with LY294002, a PI3K-AKT pathway inhibitor (P<0.05).
UNASSIGNED: TMAO may induce renal fibrosis by promoting the PI3K/AKT/SREBP1 pathway.
UNASSIGNED: A total of 20 male BALB/c mice were randomly and evenly assigned to a Control group and a TMAO group. Mice in the Control group received intraperitoneal injection of normal saline, while mice in the TMAO group received intraperitoneal injection of TMAO (20 mg/[kg·d]). The injection was given once a day for 8 weeks. Histopathology and fibrosis of kidney were observed by H&E staining and Masson staining. Immunohistochemistry was performed to determine the levels of alpha smooth muscle actin (α-SMA), recombinant human fibronectin fragment (Fibronectin), and sterol-regulatory element binding protein 1 (SREBP1). Western blot was performed to determine α-SMA, SREBP1, phosphatidylinositol 3 kinase (PI3K), phospho-phosphatidylinositol 3 kinase (p-PI3K), protein kinase B (PKB, also known as AKT), and phospho-AKT (p-AKT) protein levels. HK2 cells were treated with SREBP1 small interfering RNA (siRNA) and PI3K/AKT inhibitor, respectively, and the reversal of the effects of TMAO was examined.
UNASSIGNED: Animal experiments showed that, compared with the Control group, the mice treated with TMAO experienced pathological damage and fibrosis of the kidney tissue and the expression levels of fibrosis markers, α-SMA and Fibronectin, in the kidney were increased (all P<0.05). According to the findings from further investigation, the TMAO-treatment group showed increased expression of SREBP1 and an up-regulation of PI3K phosphorylation ratio and AKT phosphorylation ratio compared with those of the Control group (all P<0.05). Cell experiments produced results similar to those of the animal experiment. After siRNA interference with SREBP1 expression, the expression levels of fibrosis marker proteins decreased (P<0.05). Besides, the high expression of SREBP1 caused by TMAO was inhibited after HK2 cells were incubated with LY294002, a PI3K-AKT pathway inhibitor (P<0.05).
UNASSIGNED: TMAO may induce renal fibrosis by promoting the PI3K/AKT/SREBP1 pathway.
摘要：
■为了研究三甲胺N-氧化物（TMAO）的作用和机理，一种尿毒症毒素,肾纤维化。
■将总共20只雄性BALB/c小鼠随机且均匀地分配到对照组和TMAO组。对照组小鼠腹腔注射生理盐水,TMAO组小鼠腹腔注射TMAO(20mg/[kg·d])。每天一次注射，持续8周。通过H&E染色和Masson染色观察肾脏的组织病理学和纤维化。进行免疫组织化学以确定α-平滑肌肌动蛋白（α-SMA）的水平，重组人纤连蛋白片段（纤连蛋白），和固醇调节元件结合蛋白1（SREBP1）。进行蛋白质印迹以确定α-SMA，SREBP1,磷脂酰肌醇3激酶(PI3K),磷酸-磷脂酰肌醇3激酶(p-PI3K),蛋白激酶B(PKB，也称为AKT），和磷酸-AKT(p-AKT)蛋白水平。用SREBP1小干扰RNA(siRNA)和PI3K/AKT抑制剂处理HK2细胞,分别,并检查了TMAO作用的逆转。
■动物实验表明,与对照组相比，用TMAO治疗的小鼠经历了肾组织的病理损伤和纤维化以及纤维化标志物的表达水平，α-SMA和纤连蛋白，在肾脏中增加（均P<0.05）。根据进一步调查的结果，与对照组相比，TMAO治疗组SREBP1表达增加，PI3K磷酸化率和AKT磷酸化率上调（均P<0.05）。细胞实验产生的结果与动物实验相似。siRNA干扰SREBP1表达后，纤维化标志物蛋白表达水平降低(P<0.05)。此外,用PI3K-AKT途径抑制剂LY294002孵育HK2细胞后，TMAO引起的SREBP1的高表达受到抑制（P<0.05）。
■TMAO可能通过促进PI3K/AKT/SREBP1途径诱导肾纤维化。
■将总共20只雄性BALB/c小鼠随机且均匀地分配到对照组和TMAO组。对照组小鼠腹腔注射生理盐水,TMAO组小鼠腹腔注射TMAO(20mg/[kg·d])。每天一次注射，持续8周。通过H&E染色和Masson染色观察肾脏的组织病理学和纤维化。进行免疫组织化学以确定α-平滑肌肌动蛋白（α-SMA）的水平，重组人纤连蛋白片段（纤连蛋白），和固醇调节元件结合蛋白1（SREBP1）。进行蛋白质印迹以确定α-SMA，SREBP1,磷脂酰肌醇3激酶(PI3K),磷酸-磷脂酰肌醇3激酶(p-PI3K),蛋白激酶B(PKB，也称为AKT），和磷酸-AKT(p-AKT)蛋白水平。用SREBP1小干扰RNA(siRNA)和PI3K/AKT抑制剂处理HK2细胞,分别,并检查了TMAO作用的逆转。
■动物实验表明,与对照组相比，用TMAO治疗的小鼠经历了肾组织的病理损伤和纤维化以及纤维化标志物的表达水平，α-SMA和纤连蛋白，在肾脏中增加（均P<0.05）。根据进一步调查的结果，与对照组相比，TMAO治疗组SREBP1表达增加，PI3K磷酸化率和AKT磷酸化率上调（均P<0.05）。细胞实验产生的结果与动物实验相似。siRNA干扰SREBP1表达后，纤维化标志物蛋白表达水平降低(P<0.05)。此外,用PI3K-AKT途径抑制剂LY294002孵育HK2细胞后，TMAO引起的SREBP1的高表达受到抑制（P<0.05）。
■TMAO可能通过促进PI3K/AKT/SREBP1途径诱导肾纤维化。
