FAK-Activated Mucosal Healing Promotes Resistance to Reinjury

Area of Science:

• Gastroenterology
• Molecular Biology
• Pharmacology

Background:

• Gastrointestinal (GI) mucosal injury is a common side effect of long-term nonsteroidal anti-inflammatory drug (NSAID) use.
• Epithelial healing involves migration, proliferation, and angiogenesis, processes potentially modulated by focal adhesion kinase (FAK).

Purpose of the Study:

• To investigate whether novel FAK activators promote intestinal mucosal healing through enhanced angiogenesis.
• To determine if FAK activation increases resistance to reinjury in the GI tract.

Main Methods:

• Induction of ischemic jejunal ulcers in mice, followed by treatment with FAK activator ZINC40099027 (ZN27) or vehicle.
• Assessment of ulcer healing, angiogenesis, and proliferation markers via immunofluorescence.
• In vitro studies using human umbilical vein endothelial cells (HUVECs) to evaluate ZN27 effects on migration and angiogenesis.
• A reinjury model using FAK activator M64HCl and indomethacin to assess protection against recurrent NSAID-induced injury.

Main Results:

• ZN27 treatment significantly reduced ulcer size and increased angiogenesis and proliferation markers.
• In vitro, ZN27 enhanced HUVEC migration and angiogenesis in an ERK1/2-dependent manner.
• M64HCl treatment during initial injury reduced ulcer size following a second indomethacin challenge, indicating increased resistance to reinjury.

Conclusions:

• FAK activation accelerates ischemic ulcer healing, partly by enhancing angiogenesis.
• FAK activation during initial injury confers protection against recurrent NSAID-induced intestinal injury, likely through improved initial repair quality.