Related Experiment Video
Updated: Dec 25, 2025
A Quantitative Detection Method for MicroRNAs in the Kidney of an Ischemic Kidney Injury Mouse Model
Published on: September 11, 2020
MiR-133a alleviates renal injury caused by sepsis by targeting BNIP3L
1Department of Emergency, Beijing Friendship Hospital, Capital Medical University, Beijing, China. zhanghao3383@163.com.
Objective:
Sepsis is an important cause of acute kidney injury (AKI), seriously jeopardizing the health of patients. This paper's aim was to investigate whether microRNA-133a had a protective effect on sepsis-induced kidney injury.
Materials And Methods:
We established a kidney injury model with lipopolysaccharide (LPS) and divided TCMK-1 cells into 4 groups: control group (con); LPS treatment group; LPS + negative control (NC) treatment group; LPS + miR-133a mimic (mim) group. The expressions of miR-133a, TNF-α mRNA, IL-6 mRNA, Bax mRNA, Bcl-2 mRNA, BNIP3L mRNA, IκKα Mrna and IκB-α mRNA were detected by PCR. Western blot was used to detect the protein expression of TNF-α, IL-6, Bax, Bcl-2, BNIP3L, IκKα and IκB-α. Cell viability was measured by cell counting kit-8 (CCK-8). Flow cytometry was utilized to detect apoptosis rate. IL-1β immunofluorescence and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining were used to observe the inflammation and apoptosis in TCMK-1 cells.
Results:
The miR-133a expression was decreased in TCMK-1 cells treated with LPS. In the LPS treatment group, the expression of TNF-α, IL-6, Bax, BNIP3L and IκKα increased, and the expression of Bcl-2 and IκB-α decreased. When overexpressing miR-133a, the protein and mRNA expression of TNF-α, IL-6, Bax, BNIP3L and IκKα decreased markedly, while the expression of Bcl-2 and IκB-α increased markedly. Compared with the LPS-treated group, the apoptotic rate, the number of TUNEL-positive cells, and the immunofluorescence intensity of IL-1β in LPS+mim group were greatly decreased.
Conclusions:
The miR-133a expression was decreased in TCMK-1 cells treated by LPS and miR-133a can inhibit inflammation and apoptosis of TCMK-1 cells induced by LPS by targeting BNIP3L via inhibiting NF-κB pathway.
Insights
MicroRNA-133a (miR-133a) protects against sepsis-induced acute kidney injury by reducing inflammation and apoptosis. This study demonstrates that restoring miR-133a levels inhibits key inflammatory and apoptotic pathways in kidney cells.
Area of Science:
- Nephrology
- Molecular Biology
- Biochemistry
Background:
- Sepsis is a leading cause of acute kidney injury (AKI), posing a significant threat to patient health.
- MicroRNAs (miRNAs) play crucial roles in regulating cellular processes, including inflammation and apoptosis, which are implicated in AKI pathogenesis.
Purpose of the Study:
- To investigate the protective role of microRNA-133a (miR-133a) in a cellular model of sepsis-induced kidney injury.
- To elucidate the underlying molecular mechanisms by which miR-133a exerts its effects.
Main Methods:
- A lipopolysaccharide (LPS)-induced kidney injury model using TCMK-1 cells was established.
- Quantitative PCR and Western blotting were employed to assess the expression of various genes and proteins involved in inflammation and apoptosis.
- Cell viability, apoptosis rates, and inflammatory markers were evaluated using CCK-8 assay, flow cytometry, TUNEL staining, and immunofluorescence.
Main Results:
- LPS treatment led to decreased miR-133a expression and increased levels of pro-inflammatory and pro-apoptotic factors (TNF-α, IL-6, Bax, BNIP3L, IκKα), while Bcl-2 and IκB-α expression decreased.
- Overexpression of miR-133a significantly reversed these changes, reducing inflammatory and apoptotic markers.
- miR-133a mimic treatment markedly decreased cell apoptosis, TUNEL-positive cells, and IL-1β immunofluorescence intensity compared to LPS treatment alone.
Conclusions:
- miR-133a expression is downregulated in LPS-induced kidney injury.
- miR-133a demonstrates a protective effect by inhibiting inflammation and apoptosis in kidney cells.
- The mechanism involves targeting BNIP3L and inhibiting the NF-κB pathway.
