EW-7197 eluting nano-fiber covered self-expandable metallic stent to prevent granulation tissue formation in a canine urethral model

Abstract

PurposeTo evaluate an EW-7197-eluting nanofiber-covered stent (NFCS) for suppressing granulation tissue formation after stent placement in a canine urethral model.Materials and methodsAll experiments were approved by the committee of animal research. A total of 12 NFCSs were placed in the proximal and distal urethras of six dogs. Dogs were divided into two groups with 3 dogs each. The control stent (CS) group received NFCSs and the drug stent (DS) group received EW-7197 (1000 μg)-eluting NFCSs. All dogs were sacrificed 8 weeks after stent placement Histologic findings of the stented urethra were compared using the Mann-Whitney U test.ResultsStent placement was technically successful in all dogs without procedure-related complications. On urethrographic analysis, the mean luminal diameter was significantly larger in the DS group than in the CS group at 4 and 8 weeks after stent placement (all p < 0.001). On histological examination, mean thicknesses of the papillary projection, thickness of submucosal fibrosis, number of epithelial layers, and degree of collagen deposition were significantly lower in the DS group than in the CS group (all p < 0.001), whereas the mean degree of inflammatory cell infiltration was not significantly different (p > 0.05).ConclusionThe EW-7197-eluting NFCS is effective and safe for suppressing granulation tissue formation after stent placement in a canine urethral model.

Biodegradable drug-eluting urethral stent in limiting urethral stricture formation after urethral injury: An experimental study in rabbit

“…22 Previous studies showed that drugs targeting anti-inflammatory and anti-cell proliferation may be ideal candidates for stent-based therapy to prevent restenosis. 23 Kim et al 24 revealed significantly less granulation tissue formation at both time points in the rats receiving sirolimus-eluting biodegradable PLLA stent by urethrographic and histologic examinations. In this study, the biodegradable paclitaxel urethral stent we used can release paclitaxel effectively along with the degradation of stent, the drug release at early stage was rapid, and the later drug release was gradual.…”

Drug-delivering devices in the urinary tract: A systematic review

“…A total of 485 publications were screened for eligibility and 29 articles were eventually included in the systematic review (Figure 1). Table 2 [9][10][11][12][13][14][15][16][17], Tab le 3 [3,[18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] and Table 4 [3,33] show a summary of the included studies. The available studies were published over a period of 18 years (2000-2019).…”

EW‐7197 prevents ulcerative colitis‐associated fibrosis and inflammation

“…To further support of the complexity of TGFβ signaling on inflammation, Han et al () have reported that metallic stents covered with EW‐7197 did not alter inflammatory cell infiltration after stent placement in a canine urethral model. Moreover, Jun et al () indicated that although, EW‐7197 could significantly decrease the level of fibrogenic markers but had no effect on inflammatory cell infiltration in the stented esophagus of rats.…”