Procyanidins-crosslinked small intestine submucosa: A bladder patch promotes smooth muscle regeneration and bladder function restoration in a rabbit model

Partial urinary bladder outlet obstruction (PBOO) in men, secondary to benign prostatic hyperplasia, induces detrusor smooth muscle (DSM) hypertrophy. However, despite DSM hypertrophy, some bladders become severely dysfunctional (decompensated). Using a rabbit model of PBOO, we found that although DSM from sham-operated bladders expressed nearly 100% of both the smooth muscle myosin heavy chain isoform SM-B and essential light chain isoform LC17a, DSM from severely dysfunctional bladders expressed as much as 75% SM-A and 40% LC17b(both associated with decreased maximum velocity of shortening). DSM from dysfunctional bladder also exhibited tonic-type contractions, characterized by slow force generation and high force maintenance. Immunofluorescence microscopy showed that decreased SM-B expression in dysfunctional bladders was not due to generation of a new cell population lacking SM-B. Metabolic cage monitoring revealed decreased void volume and increased voiding frequency correlated with overexpression of SM-A and LC17b. Myosin isoform expression and bladder function returned toward normal upon removal of the obstruction, indicating that the levels of expression of these isoforms are markers of the PBOO-induced dysfunctional bladders.

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Use of a Novel, Reinforced, Low Immunogenic, Porcine Small Intestine Submucosa Patch to Repair a Supraspinatus Tendon Defect in a Rabbit Model

BioMed Research International ◽

10.1155/2019/9346567 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12

Author(s):

Xuancheng Zhang ◽

Zhaoyi Fang ◽

Eunshinae Cho ◽

Kai Huang ◽

Jinzhong Zhao ◽

...

Keyword(s):

Small Intestine ◽

Rabbit Model ◽

Dry Weight ◽

Supraspinatus Tendon ◽

Patch Repair ◽

Rotator Cuff Tears ◽

Dependent Manner ◽

Small Intestine Submucosa ◽

Tendon Defect ◽

Porcine Small Intestine Submucosa

Background. Repairs of large to massive rotator cuff tears have a high failure rate. We investigated the efficacy of a novel, reinforced, low immunogenic, porcine small intestine submucosa (SIS) patch to repair a supraspinatus tendon defect in a rabbit model. We hypothesized that the histological and biomechanical results of SIS patch repair would be comparable with those of autologous fascia lata (FL) repair. Methods. The study mainly comprised two parts. First, the characteristics of the SIS patch were evaluated, including its micromorphology, mechanical properties, and immunogenic properties. Second, a supraspinatus tendon defect model was created in 36 rabbits (72 shoulders). The bilateral shoulders were randomly chosen to undergo repair using either a SIS patch (SIS group) or autologous FL (FL group). At 4, 8, and 12 weeks, histological analysis was performed using four shoulders from each group, and biomechanical tests were performed using eight shoulders from each group. Results. The SIS patch was a three-dimensional construct mainly composed of collagen fibers. The mean single and double suture retention loads of the SIS patch were 48.6 ± 5.8 N and 117.9 ± 2.7 N, respectively. The DNA content in the SIS patch was 53.9 ± 10.9 ng/mg dry weight. Both the histological score and ultimate load to failure increased in a time-dependent manner in both groups, with no significant differences between the SIS and FL groups at 12 weeks. Conclusion. Repair of a large supraspinatus tendon defect using a reinforced, low immunogenic, SIS patch achieves similar effects as autologous FL in a rabbit model. This novel patch might be useful to be employed as a structural tissue replacement in medical activities.

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