Downregulating miR-184 relieves calcium oxalate crystal-mediated renal cell damage via activating the Rap1 signaling...

Area of Science:

• Nephrology
• Molecular Biology
• Biochemistry

Background:

• Renal calculi, particularly calcium oxalate (CaOx) stones, represent a significant health burden due to their high prevalence and recurrence.
• Understanding the molecular mechanisms underlying CaOx-induced kidney damage is crucial for developing effective treatments.

Purpose of the Study:

• This study investigates the role of microRNA-184 (miR-184) in regulating cellular responses to CaOx exposure in kidney cells.
• The research aims to elucidate the specific signaling pathways modulated by miR-184 during CaOx-mediated renal injury.

Main Methods:

• Experiments involved treating kidney cells (HK2, human podocytes) and a rat kidney stone model with CaOx.
• Molecular analyses included qRT-PCR for miR-184 and IGF1R, cell proliferation assays (CCK8), apoptosis detection (TUNEL), Western blotting for key proteins and signaling pathways (NF-κB, Nrf2/HO-1, Rap1), and ELISA for inflammatory factors.
• miR-184's interaction with IGF1R was confirmed using dual luciferase and RNA immunoprecipitation assays.

Main Results:

• CaOx treatment led to increased miR-184 levels in both cell cultures and a rat kidney stone model.
• Inhibition of miR-184 mitigated CaOx-induced inflammation, apoptosis, and oxidative stress, while simultaneously activating the Rap1 signaling pathway.
• miR-184 was found to directly target Insulin-like Growth Factor 1 Receptor (IGF1R).
• IGF1R activation counteracted the protective effects of miR-184, and Hippo pathway suppression reversed the benefits of miR-184 knockdown.

Conclusions:

• Downregulation of miR-184 promotes renal cell protection against CaOx-induced damage.
• Activation of the Rap1 signaling pathway by reduced miR-184 levels is a key mechanism in ameliorating kidney injury.
• These findings highlight miR-184 as a potential therapeutic target for managing kidney stone disease.