MircoRNA-145 promotes activation of hepatic stellate cells via targeting krüppel-like factor 4

Area of Science:

• Molecular biology
• Hepatology
• Fibrosis research

Background:

• Krüppel-like Factor 4 (KLF4) is known to inhibit lung fibrosis.
• The role of KLF4 and miR-145 in hepatic stellate cells (HSCs) activation and liver fibrosis remains unclear.
• Understanding these molecular players is crucial for developing new therapeutic strategies for liver fibrosis.

Purpose of the Study:

• To investigate the role and molecular mechanism of miR-145 and KLF4 in HSC activation and liver fibrosis.
• To characterize the expression patterns of miR-145 and KLF4 in activated HSCs and cirrhotic liver tissues.
• To elucidate the regulatory relationship between miR-145 and KLF4 in the context of liver fibrosis.

Main Methods:

• Primary rat HSCs were isolated and treated with TGF-β to induce activation.
• miR-145 mimics and inhibitors were used to modulate miR-145 levels in HSCs.
• KLF4 expression was inhibited using specific shRNA and overexpressed to study its effects.
• Expression levels of α-SMA and COL-I (collagen type I) were measured as markers of HSC activation and fibrosis.
• KLF4 mRNA and protein levels were assessed in cirrhotic patient and rat liver samples.

Main Results:

• miR-145 was significantly upregulated, while KLF4 was downregulated during HSC activation.
• miR-145 mimics increased, and miR-145 inhibition decreased α-SMA and COL-I expression in HSCs.
• KLF4 mRNA and protein levels were significantly reduced in cirrhotic livers.
• KLF4 inhibition led to increased α-SMA and COL-I expression, while KLF4 overexpression reduced them.
• These findings indicate that miR-145 promotes HSC activation and liver fibrosis by targeting KLF4.

Conclusions:

• miR-145 plays a critical role in promoting HSC activation and liver fibrosis.
• KLF4 acts as a suppressor of HSC activation and liver fibrosis.
• The miR-145/KLF4 axis is a key molecular mechanism driving liver fibrosis progression.
• Targeting the miR-145/KLF4 pathway may offer a novel therapeutic approach for liver fibrosis.