Anti-Inflammatory and Tissue Adhesion Properties of an α-Linolenic Acid-Modified Gelatin-Based In Situ Hydrogel.

Poly unsaturated fatty acids (PUFAs)-natural chemicals derived from fish and nuts-have anti-inflammatory and antioxidative properties that are attributed to the inhibition of inflammatory pathways and the radical scavenging activity of their double bonds. In this study, Alaska pollock-derived gelatin (ApGltn), which has a low sol-gel transition temperature, was modified with α-linolenic acid (ALA) to obtain ALA-ApGltn, which was subsequently cross-linked to give a hydrogel (ALA-gel). Although the elastic modulus of ALA-gel and nonmodified ApGltn gel (Org-gel) was almost the same, ALA-gel exhibited a higher tan δ as well as a lower swelling ratio and enzymatic degradation rate than Org-gel. Moreover, ALA-gel showed enhanced tissue adhesive strength compared with a commercial fibrin adhesive. The concentration of a tumor necrosis factor (TNF)-α secreted from macrophage-like cells and the intracellular mitochondrial activity indicated that ALA-ApGltn exerted anti-inflammatory effects and maintained cell viability compared with the higher toxicity nonconjugated ALA. In addition, ALA-gel demonstrated suppressed formation of lamellipodia and secretion of TNF-α. ALA-gel therefore has potential as an adhesive biomaterial for wound sealing and treating burn injuries.