Insulin‐like growth factor 1 sustained‐release collagen on urethral catheter prevents stricture after urethral injury in a rabbit model

Abstract

Objectives To evaluate the preventive effect of an insulin‐like growth factor 1 sustained‐release collagen urethral catheter on urethral stricture after urethral injury in a rabbit model. Methods We made urethral catheters coated either with insulin‐like growth factor 1 impregnated collagen or with only collagen, and we divided 19 male Japanese white rabbits into three groups according to the kind of catheter inserted immediately after the rabbit's urethra was injured by electrocoagulation. Group 1 (n = 7) had a catheter coated with insulin‐like growth factor 1 impregnated collagen inserted; group 2 (n = 7) had a catheter coated with only collagen inserted; and group 3 (n = 5) had an uncoated catheter inserted. A total of 14 days later, the injured urethras were evaluated by urethrography and urethroscopy, and were also histologically examined. Results Urethrography showed that the ratio of the urethral lumen diameter in injured urethra to that in normal urethra was the largest in group 1 (P < 0.0001). In addition, five of the seven rabbits in group 1 (71.4%) had a urethral lumen large enough for passage of a urethroscope, a fraction larger than the corresponding fractions in groups 2 (57.1%) and 3 (20%). On histological analysis, the injured area not covered with regenerated urethral epithelium tended to be smaller in group 1 than the other two groups, but the mean difference was not significant (P = 0.19). Conclusions An insulin‐like growth factor 1 sustained‐release collagen urethral catheter significantly improves wound healing and prevents urethral stricture after urethral injury.

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

“…The current mitotic drugs used in anti-scar treatment are steroid drugs and antitumor drugs including docetaxel, corticosteroid, 5-fluorouracil, bleomycin, mitomycin C, and retinoic acid. 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.…”

Successful engraftment of epithelial cells derived from autologous rabbit buccal mucosal tissue, encapsulated in a polymer scaffold in a rabbit model of a urethral stricture, transplanted using the transurethral approach

“…We followed the method reported by Shinchi et al. [ 5 ] and successfully formed strictures. TGP-encapsulated cell transplantation was performed without hurdles.…”

“…2 ). The urethra was injured by electrocoagulation with spherical monopolar electrocautery, wherein a spherical electrode was inserted into the bulbar urethra from the external urethral meatus and used for 30 s of electrocoagulation at 40 W [ 5 ]. Retrograde urethrography and urethroscopy observations were carried out to confirm the injured urethral segments immediately and after 14 days to confirm the stricture's creation ( Fig.…”

“…Therefore, we report herein the successful creation of urethral stricture in a rabbit model, which potentially could mimic urethral stricture in humans, following the protocol of Shinichi et al. [ 5 ] and the successful transplantation of autologous in vitro cultured rabbit buccal mucosal cells using the BEES-HAUS approach [ 4 ].…”

Growth Factors, Reactive Oxygen Species, and Metformin—Promoters of the Wound Healing Process in Burns?

“…The study results reported that IGF-1 promotes the wound healing of skin ulcers in diabetic rats [114]. Shinchi et al revealed in a rabbit model that IGF-1 may sustain the collagen release and significantly improves the wound healing and may prevent the urethral stricture after urethral injury [115]. IGF-1 has a therapeutic effect even in the healing of gingival mucosa damage [116].…”