Evaluation of Angiogenic Factor Release From Thermosensitive Poly N-Vinylcaprolactam -g-Collagen: In Vitro and In Vivo Studies

I n this study, a thermosensitive poly N-vinylcaprolactam -g-collagen PNVCL-g-Col hybrid hydrogel was synthesized by conjugation using the NHS/EDC cross-linking system, and characterized. At first, the efficiency of in vitro sustained delivery of human vascular endothelial growth factor VEGF from the thermosensitive PNVCL-g-Col hydrogel modified with heparin, was evaluated for duration of ten days under in vitro physiological conditions 37oC, pH 7.4 . The results indicated that PNVCL-g-Col hydrogel preserved its stability and released ~90% of the loaded VEGF within this time period. In vitro study showed that PNVCL-g-Col was basically histocompatible. Then, the in vivo angiogenic activity of the VEGF-releasing PNVCL-g-Col was investigated using a subcutaneous rat model. In vivo study confirmed that angiogenic-factor-loaded PNVCL-g-Col had the capacity to induce neovascularization indicating that the in vivo bioactivity of the VEGF was preserved in the thermosensitive PNVCL-g-Col

Keywords:

Thermosensitive polymer, Sustained release, Conjugation, Angiogenesis, Hybrid hydrogel VEGF.,

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