COX-2-10aa-PGIS gene therapy improves erectile function in rats after cavernous nerve injury.

Erectile dysfunction (ED) is a very common complication after radical prostatectomy. COX-2-10aa-PGIS is a newly engineered protein with COX-2 and prostacyclin synthase activities that converts arachidonic acid directly to prostacyclin (prostaglandin I2 [PGI2]). PGI2 is a potent smooth muscle relaxant. The purpose of this study was to explore the effect and mechanism of COX-2-10aa-PGIS gene therapy in penile rehabilitation. Bilateral cavernous nerve crush (BCNC) in adult Sprague-Dawley rats was used to mimic radical prostatectomy-induced ED. Sprague-Dawley rats were randomly assigned into four groups: 1. sham surgery; 2. BCNC; 3. BCNC + null control recombinant adenovirus intracavernous injection; and 4. BCNC + Ad-COX2-10aa-PGIS intracavernous injection. Twenty-eight days later, intracavernosal pressure (ICP) was recorded under cavernous nerve stimulation; in the meantime, the mean arterial pressure (MAP) was monitored. At the end of the measurement, the penis was harvested and processed for (i) immunohistochemistry analysis of endothelial nitric oxide synthase (eNOS), alpha-smooth muscle actin (α-SMA), and transforming growth factor beta-1 (TGF-β1); (ii) Masson's trichrome stain for smooth muscle/collagen ratios; (iii) Western blot of eNOS, α-SMA, TGF-β1, and COX2-10aa-PGIS; and (iv) terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay for apoptosis. Erectile function was evaluated by ICP/MAP. Smooth muscle and endothelium functions in corpora cavernosum were assessed by Masson's trichrome stain, immunohistochemistry, and Western blot. Apoptosis was identified by TUNEL assay. The results were the following: 1. COX2-10aa-PGIS gene therapy improved erectile function (82%, compared with control) in the BCNC rat model; 2. COX2-10aa-PGIS gene therapy increased eNOS (121%) and α-SMA (118%) expression and decreased TGF-β1 (45%) expression; 3. COX2-10aa-PGIS gene therapy reduced cell apoptosis after cavernous nerve injury (64%); and 4. COX2-10aa-PGIS gene therapy improved smooth muscle/collagen ratios (81%). Our data demonstrated that COX2-10aa-PGIS improved erectile function after cavernous nerve injury through antifibrotic and anti-apoptotic mechanisms.

Lin H ，Yuan J ，Ruan KH ，Yang W ，Zhang J ，Dai Y ，Wang R ... -  《-》

Molecular mechanisms of vacuum therapy in penile rehabilitation: a novel animal study.

Penile rehabilitation (PR) is widely applied after radical prostatectomy. Vacuum erectile device (VED) therapy is the one of three PR methods used in the clinical setting that improve erectile function (EF) and is the only PR method which may preserve penile length. However, its unknown mechanism hampered doctors' recommendations and patients' compliance. To assess the effects of VED therapy on erectile dysfunction (ED) in a rat model of bilateral cavernous nerve crush (BCNC) and to investigate the molecular mechanism of VED in postprostatectomy ED. This was an experimental study using Sprague-Dawley rats in three groups: sham, BCNC, and BCNC plus VED. Intervention included BCNC, electrical stimulation of the cavernous nerve (CNS), and VED therapy. At the end of a 4-wk period, CNS was used to assess EF by maximum intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio and duration (area under the curve [AUC]). For the structural analyses, whole rat penis was harvested. Terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling assay was used for the assessment of apoptotic indices (AI). Immunohistochemistry was performed for endothelial nitric oxide synthase (eNOS), α-smooth muscle actin (ASMA), transforming growth factor beta 1 (TGF-β1), and hypoxia inducible factor-1α (HIF-1α). Staining for Masson's trichrome was utilized to calculate the smooth muscle/collagen ratios. EF was improved with VED therapy measured by ICP/MAP ratios and AUC. VED therapy reduced HIF-1α expression and AI significantly compared with control. Animals exposed to VED therapy had decreased TGF-β1 expression, increased smooth muscle/collagen ratios, and preserved ASMA and eNOS expression. To our knowledge, this is the first scientific study to suggest that VED therapy in the BCNC rat model preserves EF through antihypoxic, antiapoptotic, and antifibrotic mechanisms.

Yuan J ，Lin H ，Li P ，Zhang R ，Luo A ，Berardinelli F ，Dai Y ，Wang R ... -  《-》

Effectiveness of intracavernous delivery of adenovirus encoding Smad7 gene on erectile function in a mouse model of cavernous nerve injury.

Men with erectile dysfunction (ED) respond poorly to oral phosphodiesterase-5 inhibitors following radical prostatectomy. Recent studies have reported that up-regulation of transforming growth factor-β1 (TGF-β1) and activation of the Smad signaling pathway play important roles in cavernous fibrosis and in the deterioration of erectile function in a mouse model of cavernous nerve injury (CNI) and in patients with spinal cord injury. The mothers against decapentaplegic homolog 7 (Smad7) is known to inhibit the phosphorylation of Smad2 and Smad3. To investigate the effectiveness of adenoviruses encoding Smad7 gene (Ad-Smad7) on erectile function in a mouse model of CNI. Twelve-week-old C57BL/6J mice were used and distributed into 7 groups: sham operation group, untreated CNI group, and CNI groups receiving a single intracavernous injection of adenovirus encoding LacZ (1 × 10(8) virus particles [vp]/20 μL) or adenovirus encoding Smad7 (Ad-Smad7; 1 × 10(7), 1 × 10(8), 2 × 10(8), or 1 × 10(9) vp/20 μL). Two weeks after bilateral cavernous nerve crushing and treatment, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was harvested for histologic examinations and Western blot analysis. The highest erectile response was noted in CNI mice treated with Ad-Smad7 at a dose of 1 × 10(8)  vp, which reached up to 82-85% of sham control values. Local delivery of Ad-Smad7 significantly decreased endothelial cell apoptosis and the production of extracellular matrix proteins, including plasminogen activator inhibitor-1, fibronectin, collagen I, and collagen IV, and induced endothelial nitric oxide synthase phosphorylation in the corpus cavernosum tissue of CNI mice. The adenovirus-mediated gene transfer of Smad7 successfully restored erectile function by enhancing endothelial cell function and through antifibrotic effects. These findings suggest that inhibition of the TGF-β signaling pathway by use of Smad7 may represent a promising therapeutic strategy for ED induced by radical prostatectomy.

Song KM ，Chung JS ，Choi MJ ，Jin HR ，Yin GN ，Kwon MH ，Park JM ，Kim WJ ，Lee SJ ，Kim SJ ，Ryu JK ，Suh JK ... -  《-》

N-acetylcysteine maintains penile length and erectile function in bilateral cavernous nerve crush rat model by reducing penile fibrosis.

Ma M ，Wu CJ ，Zhang P ，Li T ，Wei SZ ，Yu BT ，Qin F ，Yuan JH ... -  《-》

Transplantation of Human Urine-Derived Stem Cells Transfected with Pigment Epithelium-Derived Factor to Protect Erectile Function in a Rat Model of Cavernous Nerve Injury.

Yang Q ，Chen X ，Zheng T ，Han D ，Zhang H ，Shi Y ，Bian J ，Sun X ，Xia K ，Liang X ，Liu G ，Zhang Y ，Deng C ... -  《-》