ABSTRACT
BACKGROUND: Acute kidney injury (AKI) was characterized by loss of renal function, associated with chronic kidney disease, end-stage renal disease, and length of hospital stay. Long non-coding RNAs (lncRNAs) participated in AKI development and progression. Here, we aimed to investigate the roles and mechanisms of lncRNA MALAT1 in AKI. METHODS: AKI serum samples were obtained from 129 AKI patients. ROC analysis was conducted to confirm the diagnostic value of MALAT1 in differentiating AKI from healthy volunteers. After hypoxic treatment on HK-2 cells, the expressions of inflammatory cytokines, MALAT1, miR-204, APOL1, p65, and p-p65, were measured by RT-qPCR and Western blot assays. The targeted relationship between miR-204 and MALAT1 or miR-204 and APOL1 was determined by luciferase reporter assay and RNA pull-down analysis. After transfection, CCK-8, flow cytometry, and TUNEL staining assays were performed to evaluate the effects of MALAT1 and miR-204 on AKI progression. RESULTS: From the results, lncRNA MALAT1 was strongly elevated in serum samples from AKI patients, with the high sensitivity and specificity concerning differentiating AKI patients from healthy controls. In vitro, we established the AKI cell model after hypoxic treatment. After experiencing hypoxia, we found significantly increased MALAT1, IL-1ß, IL-6, and TNF-α expressions along with decreased miR-204 level. Moreover, the targeted relationship between MALAT1 and miR-204 was confirmed. Silencing of MALAT1 could reverse hypoxia-triggered promotion of HK-2 cell apoptosis. Meanwhile, the increase of IL-1ß, IL-6, and TNF-α after hypoxia treatment could be repressed by MALAT1 knockdown as well. After co-transfection with MALAT1 silencing and miR-204 inhibition, we found that miR-204 could counteract the effects of MALAT1 on HK-2 cell progression and inflammation after under hypoxic conditions. Finally, NF-κB signaling was inactivated while APOL1 expression was increased in HK-2 cells after hypoxia treatment, and lncRNA MALAT1 inhibition reactivated NF-κB signaling while suppressed APOL1 expression by sponging miR-204. CONCLUSIONS: Collectively, these results illustrated that knockdown of lncRNA MALAT1 could ameliorate AKI progression and inflammation by targeting miR-204 through APOL1/NF-κB signaling.
Subject(s)
Acute Kidney Injury/genetics , Apolipoprotein L1/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/blood , Acute Kidney Injury/metabolism , Acute Kidney Injury/pathology , Adult , Apolipoprotein L1/metabolism , Case-Control Studies , Cell Hypoxia/genetics , Cell Line , Female , Gene Expression Regulation , Gene Knockdown Techniques , Humans , Kidney Function Tests , Male , MicroRNAs/antagonists & inhibitors , Middle Aged , NF-kappa B/genetics , NF-kappa B/metabolismABSTRACT
OBJECTIVE: To study the effect of mahogunin ring finger-1 (MGRN1) on the autophagy of Sertoli cells in mice. METHODS: Using RNA interference, we down-regulated the expression of MGRN1 in the mouse TM4 Sertoli cells cultured in vitro, determined the expressions of the autophagy-related proteins LC3-II/I, ATG-5 and ATG-7 by Western blot, and detected the autophagosomes in the TM4 cells by immunofluorescence and electron microscopy. RESULTS: Western blot showed increased expressions of LC3-II/I, ATG-5 and ATG-7 in the mouse TM4 Sertoli cells after knockdown of MGRN1. Fluorescence microscopy revealed significantly more autophagosomes in the TM4 cells than in the control group (P < 0.05). CONCLUSIONS: MGRN1 affects the autophagy of mouse Sertoli cells, and its specific molecular mechanism needs to be further studied.
