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bioRxiv · 10.1101/2024.01.01.569918

Orally delivered biodegradable targeted inflammation resolving pectin-coated nanoparticles induce anastomotic healing post intestinal surgery

Abstract

Although medical treatment is sucessful in most cases in patients with inflammatory bowel diseases (IBD), a percentage of patients require surgical resection of diseased bowel segments at least once in their lifetime. Healing success of the intestinal anastomosis is at high risk, especially in presence of acute inflammation. Failure of anastomotic healing is a life-threatening complication and causes high socioeconomic costs. Common anti-inflammatory medications can have detrimental effects on wound healing. Thus, targeted perioperative therapeutics supporting anastomotic healing during colitis are an urgent medical need. Here, we develop a novel basal membrane targeted controlled release, pectin-coated polymeric nanoparticle (NP) encapsulating a highly potent inflammation resolving mediator, the peptide Ac2-26. These NPs can undergo gastric passage and facilitate localized release of the therapeutic peptide in the colon via degradation of their pectin-chitosan coating by microbial pectinases, which subsequently exposes a collagen IV targeted NP surface, allowing for further binding and retention of the NPs at the intestinal wound. To test these NPs, we used a murine surgical model combining the formation of an intestinal anastomosis with the induction of a preoperative colitis by dextran sodium sulfate. In this model, perioperative administration of pectin-chitosan coated NPs containing Ac2-26 (P-C-Col IV-Ac2-26-NP) led to the reduction of colitis activity in the postoperative phase. Macroscopic wound closure was improved by P-C-Col IV-Ac2-26-NP treatment as evaluated by endoscopy and intraabdominal adhesion scoring. Microscopic analysis of the healing process showed an improved semiquantitative healing score in the treatment group. In this proof-of-concept study we demonstrate that novel P-C-Col IV-Ac2-26-NP could be a promising and clinically feasible perioperative treatment strategy for IBD patients. TOC graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=135 SRC="FIGDIR/small/569918v1_ufig1.gif" ALT="Figure 1"> View larger version (53K): org.highwire.dtl.DTLVardef@14f726dorg.highwire.dtl.DTLVardef@e1739aorg.highwire.dtl.DTLVardef@16ca7d0org.highwire.dtl.DTLVardef@7d87fe_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

Lee, J. H., Reischl, S., Walter, R. L., Vieregge, V., Weber, M.-C., Xu, R., Chen, H., Kasajima, A., Friess, H., Neumann, P.-A., Kamaly, N.. 2024-01-02. Orally delivered biodegradable targeted inflammation resolving pectin-coated nanoparticles induce anastomotic healing post intestinal surgery. https://doi.org/10.1101/2024.01.01.569918

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