Targeting STAT5 attenuates retinal neovascularization by promoting apoptosis and suppressing endothelial cell...

Area of Science:

• Ophthalmology
• Molecular Biology
• Cell Biology

Background:

• Signal transducer and activator of transcription 5 (STAT5) is a known regulator of tumor growth and angiogenesis.
• The specific role of STAT5 in retinal neovascularization (RNV) is not well understood.
• Retinal neovascularization is a hallmark of several vision-threatening diseases.

Purpose of the Study:

• To investigate the role of STAT5 in the progression of RNV.
• To identify the molecular pathways through which STAT5 influences RNV.
• To evaluate the therapeutic potential of STAT5 inhibition in RNV.

Main Methods:

• An oxygen-induced retinopathy (OIR) mouse model was established.
• STAT5 inhibitor was administered intravitreally to OIR mice.
• Western blot and immunofluorescence were used to assess protein levels and localization.
• Retinal neovascularization, apoptosis, and endothelial cell functions (proliferation, migration, tube formation) were quantified and analyzed.

Main Results:

• STAT5 and phosphorylated STAT5 (p-STAT5) levels were elevated in OIR mouse retinas, particularly in neovascular regions.
• STAT5 inhibition significantly reduced RNV areas and decreased STAT5/p-STAT5 levels.
• STAT5 inhibition increased apoptosis markers (PARP-1, Caspase-3/9, Bax/Bcl-2) in retinal neovascular regions.
• Inhibition of STAT5 suppressed proliferation, migration, invasion, and tube formation in human retinal microvascular endothelial cells (HRMVECs).

Conclusions:

• STAT5 signaling plays a crucial role in promoting RNV.
• STAT5 enhances RNV by promoting endothelial cell survival and angiogenic functions.
• Targeting STAT5 signaling represents a promising therapeutic strategy for RNV.