Apparatuses, methods, and compositions for the treatment and prophylaxis of chronic wounds
According to an illustrative embodiment a method to promote healing of a wound is provided comprising contacting the wound with a biologically active composition comprising a lipoic acid derivative and gelatin. In another embodiment a wound dressing is provided comprising a scaffold coated with a biologically active composition comprising a lipoic acid derivative. In a further embodiment, a system is provided for treating a tissue site of a patient, the system comprising a reduced-pressure source to supply reduced pressure, a manifold to distribute reduced pressure to a tissue site and a scaffold coated with a biologically active composition comprising a lipoic acid derivative. Methods for producing such a system and scaffold are also disclosed.
1. A dressing for treating a tissue site, comprising:
a manifold comprising an open-cell foam having a plurality of flow channels adapted to distribute reduced pressure through the manifold; and
a composition for reducing excessive matrix metalloprotease activity coated on at least a portion of the manifold, wherein the composition comprises:
a gelatin substrate as a sacrificial proteolytic enzyme substrate,
a lipoic acid derivative, and
a chelating agent capable of reducing matrix metalloprotease activity.
2. The dressing of claim 1 , wherein the gelatin substrate comprises exposed peptide sequences adapted to serve as signals for matrix metalloprotease binding.
3. The dressing of claim 1 , wherein the lipoic acid derivative comprises a pharmaceutically-acceptable salt.
4. The dressing of claim 1 , wherein the lipoic acid derivative is alpha-lipoic acid or a pharmaceutically-acceptable salt of alpha-lipoic acid.
5. The dressing of claim 1 , wherein the composition comprises 0.1% to 25% w/w gelatin substrate.
6. The dressing of claim 1 , wherein the composition comprises 0.1% to 5% w/v lipoic acid derivative.
7. The dressing of claim 1 , wherein the composition further comprises an antimicrobial agent, a growth factor, or a preservative.
8. The dressing of claim 7 , wherein the antimicrobial agent is non-ionic silver, polyhexamethylene biguanide, chlorhexidine, benzalkonium chloride, or triclosan.
9. The dressing of claim 1 , wherein the chelating agent comprises ethylenediaminetetraacetic acid.
10. The dressing of claim 1 , wherein the manifold comprises an open-cell polyurethane foam.
11. The dressing of claim 1 , further comprising a scaffold adapted to be positioned between the manifold and the tissue site, wherein the scaffold has a plurality of passages.
12. The dressing of claim 11 , further comprising a release layer adapted to be positioned between the scaffold and the manifold.
13. A composition for applying to a tissue dressing for reducing excessive matrix metalloprotease activity, comprising:
a sacrificial matrix metalloprotease substrate comprising gelatin and having exposed peptide sequences adapted to serve as signals for matrix metalloprotease binding;
a lipoic acid derivative; and
a chelating agent comprising ethylenediaminetetraacetic acid for reducing matrix metalloprotease activity.
14. The composition of claim 13 , wherein the lipoic acid derivative comprises a pharmaceutically-acceptable salt.
15. The composition of claim 13 , wherein the lipoic acid derivative is alpha-lipoic acid or a pharmaceutically-acceptable salt of alpha-lipoic acid.
16. The composition of claim 13 , wherein the composition comprises 0.1% to 25% w/w gelatin substrate.
17. The composition of claim 13 , wherein the composition comprises 0.1% to 5% w/v lipoic acid derivative.
18. The composition of claim 13 , further comprising an antimicrobial agent, a growth factor, or a preservative.
19. A wound dressing, comprising:
a porous polyurethane material; and
a composition comprising a sacrificial proteolytic enzyme substrate and a lipoic acid derivative, the composition provided on at least a portion of the porous polyurethane material;
wherein the lipoic acid derivative is a dihydrolipoic acid comprising the structure:
wherein n1 and n2 are, independently, C 1 -C 10 alkyl;
R 1 is H, C 1 -C 10 alkyl, C 6 -C 14 aryl, an alkyl ammonium or a protonated amino acid; and
R 2 is H, C 1 -C 10 alkyl or C 6 -C 14 aryl.
20. The wound dressing of claim 19 , wherein the composition further comprises an antimicrobial agent, a growth factor, a proteinase inhibitor, a chelating agent or a preservative.