RESUMO
BACKGROUND: Renal interstitial fibrosis (RIF) seriously threatens the health of individuals. MiRNAs regulate the progression of fibrosis. Nevertheless, the detailed function of miR-449a in RIF is largely unknown. METHODS: In vitro and in vivo models of RIF were developed to evaluate the function of miR-449a. The relationship among miR-449a, KLF4, and MFN2 was explored using a dual-luciferase reporter assay and chromatin immunoprecipitation. Additionally, the pathological changes in the mice were detected using Masson staining. The mRNA and protein expressions were assessed using quantitative reverse transcription polymerase chain reaction and western blot, respectively. RESULTS: TGF-ß1 downregulated the expressions of KLF4 and MFN2 in TCMK-1 cells, but upregulated the level of miR-449a. The downregulation of miR-449a significantly inhibited TGF-ß1-induced upregulation of fibrotic proteins in TCMK-1 cells. Meanwhile, miR-449a directly targeted KLF4. Moreover, KLF4 overexpression activated MFN2 transcription and reversed TGF-ß1-induced fibrosis by positively regulating MFN2. Furthermore, the downregulation of miR-449a could obviously alleviate the symptoms of RIF in mice with unilateral ureteral obstruction. CONCLUSION: MiR-449a downregulation attenuated the development of RIF by mediating the KLF4/MFN2 axis. Therefore, miR-449a might act as a target in treating RIF.
Assuntos
Nefropatias , MicroRNAs , Animais , Camundongos , Regulação para Baixo , Fibrose , Nefropatias/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Aims: The authors aim to investigate the function of circPlekha7 in renal fibrosis. Methods: Human renal tissues from chronic kidney disease patients, kidney cell line and primary cultured renal tubular epithelial cells were used. TGF-ß1-treated human kidney 2 cells/tubular epithelial cells and a unilateral ureteral obstruction mouse model were employed to study renal fibrosis. Results: circPlekha7 was diminished in renal tissues from chronic kidney disease patients and TGF-ß1-treated human kidney 2 cells and tubular epithelial cells, while miR-493-3p was upregulated. Overexpression of circPlekha7 or knockdown of miR-493-3p suppressed TGF-ß1 induced enhancements on epithelial to mesenchymal transition and fibrogenesis, as well as attenuated renal fibrosis and injury in mice subjected to unilateral ureteral obstruction. circPlekha7 bound with miR-493-3p, which directly targeted KLF4. Conclusion: circPlekha7 inhibits epithelial to mesenchymal transition of renal tubular epithelial cells and fibrosis via targeting miR-493-3p to de-repress KLF4/mitofusin2 expression.
Chronic kidney disease (CKD) ultimately leads to complete kidney dysfunction. The incidence of CKD continues to rise as a result of the increasingly aging population, and the treatment is very limited. In this study, the authors identified a novel molecule, circPlekha7, that plays a crucial role in CKD development and progression. The level of circPlekha7 is lower in the kidney tissues of CKD patients, and increasing its level could attenuate kidney injury and fibrosis. This work helps researchers understand the disease better and, more importantly, provides new avenues to develop therapy.
Assuntos
MicroRNAs , RNA Circular , Insuficiência Renal Crônica , Animais , Transição Epitelial-Mesenquimal , Fibrose , Humanos , Rim/patologia , Fator 4 Semelhante a Kruppel/genética , Fator 4 Semelhante a Kruppel/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Transdução de SinaisRESUMO
Salvianolic acid A, salvianolic acid B, danshensu, protocatechuic aldehyde, rosmarinic acid and lithospermic acid are the six major active constituents in Danshen injection. In this study, a rapid, sensitive and specific liquid chromatographic-electrospray ionization-mass spectrometry method for the simultaneous quantitative determination of these compounds in rat plasma was developed. After a single step of liquid-liquid extraction with ethyl acetate, they were eluted by a Hypersil C18 column (5 µm, i.d. 4.6 × 200 mm) within 4 min with a mobile phase consisting of acetonitrile and 0.1% formic acid water solution (35:65, v/v). The assay was linear in the concentration range of 0.05-10 µg mL(-1). Absolute recoveries were above 60%. The precisions and accuracies determined within three consecutive days were within acceptable limits. The method was successfully applied to a pharmacokinetic study in rats after an intravenous administration of Danshen injection.
