Wei-Ren Li

The TGF-β1/Smad/CTGF Pathway and Corpus Cavernosum Fibrous-Muscular Alterations in Rats With Streptozotocin-Induced Diabetes

Diabetes-associated erectile dysfunction is associated with increased extracellular matrix deposition and reduced smooth muscle content in the corpus cavernosum. The mechanisms of these processes are not well understood. In this study, we investigated fibromuscular changes in the corpus cavernosum of rats with streptozotocin-induced diabetes to determine the mechanisms underlying pathologic changes in penile structure and function. Forty 8-week-old Sprague-Dawley rats were randomly distributed into control and diabetic groups. Diabetes was induced by a one-time intraperitoneal injection of streptozotocin 60 mg/kg. Twelve weeks later, erectile function was measured by cavernous nerve electrostimulation with real-time intracorporal pressure assessment. The penis was harvested for histologic examination (Masson trichrome stain, picrosirius red stain, Hart elastin stain, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, and immunohistochemistry) and Western blot. Diabetes significantly attenuated erectile response to cavernous nerve electrostimulation. Diabetic animals exhibited a decreased smooth muscle/collagen ratio in the corpus cavernosum. The ratio of collagen I to II fibers was significantly lower in the corpora of diabetic rats compared with controls. Cavernous elastic fibers were fragmented in diabetic rats. There was up-regulation of the transforming growth factor β1/Smad/connective tissue growth factor signaling pathway in diabetic rats. Phospho-Smad2 expression was higher in smooth muscle cells and fibroblasts of diabetic rats, as was the apoptotic index. The up-regulation of the transforming growth factor β1/Smad/connective tissue growth factor signaling pathway might play an important role in diabetes-induced fibrous-muscular structural changes and deterioration of erectile function.

Icarisid II, a PDE5 inhibitor from Epimedium wanshanense, increases cellular cGMP by enhancing NOS in diabetic ED rats corpus cavernosum tissue

The aim of this study was to explore the effects and mechanisms of Icarisid II (ICA‐II) on enhancing the cellular cGMP in rat corpus cavernosum tissue (RCCT). Diabetes mellitus Wistar rats were induced by streptozotocin, and diabetic ED rats were selected for the RCCT culture by apomorphine. ICA‐II was extracted and purified from Icariin (ICA) by enzymatic method. The RCCT was treated with ICA‐II, ICA and Sildenafil at different concentrations. cGMP and nitric oxide synthase (NOS) activities were checked respectively by enzyme immunoassay. Meanwhile, nNOS, iNOS and eNOS in RCCT were checked by western blot. ICA‐II evaluated the intracellular cGMP to 8.01 ± 1.02 pmol mg−1 min−1, which is much weaker than that from Sildenafil (12.4 ± 1.16 pmol mg−1 min−1) (P < 0.05). There is no significant difference between ICA‐II and ICA. With the treatment of 10 μm ICA‐II for 24 and 48 h, nNOS expression was significantly increased in RCCT (P < 0.05), while the eNOS expression level was very low without any change. Notably, ICA‐II increased the intracellular NOS activity significantly in vitro in RCCT. Except the PDE5 inhibitory effect, ICA‐II increases the intracellular cGMP through the enhancement of nNOS expression and NOS activity in RCCT in vitro. ICA‐II implies a potential compound for neurogenic erectile dysfunction by NO–cGMP pathway.

Autophagic deficiency is related to steroidogenic decline in aged rat Leydig cells.

Late-onset hypogonadism (LOH) is closely related to secondary androgen deficiency in aged males, but the mechanism remains unclear. In this study, we found that reduced testosterone production in aged rat Leydig cells is associated with decreased autophagic activity. Primary rat Leydig cells and the TM3 mouse Leydig cell line were used to study the effect of autophagic deficiency on Leydig cell testosterone production. In Leydig cells from young and aged rats, treatment with wortmannin, an autophagy inhibitor, inhibited luteinising hormone (LH)-stimulated steroidogenic acute regulatory (StAR) protein expression and decreased testosterone production. In contrast, treatment with rapamycin, an autophagy activator, enhanced LH-stimulated steroidogenesis in Leydig cells from aged, but not young, rats. Intracellular reactive oxygen species (ROS) levels were increased in both young and aged Leydig cells treated with wortmannin but decreased only in aged Leydig cells treated with rapamycin. Furthermore, an increased level of ROS, induced by H(2)O(2), resulted in LH-stimulated steroidogenic inhibition. Finally, knockdown of Beclin 1 decreased LH-stimulated StAR expression and testosterone production in TM3 mouse Leydig cells, which were associated with increased intracellular ROS level. These results suggested that autophagic deficiency is related to steroidogenic decline in aged rat Leydig cells, which might be influenced by intracellular ROS levels.

Activation of VEGF and ERK1/2 and improvement of urethral function by adipose-derived stem cells in a rat stress urinary incontinence model.

OBJECTIVE To investigate the injected autologous adipose-derived stem cells (ADSCs) in improving stress urinary incontinence in a rodent model of parturition-related stress incontinence and the possible mechanism. METHODS The 40 rats were developed stress urinary incontinence models by postpartum balloon dilation of the vagina for 4 hours followed by bilateral ovariectomy. ADSCs were isolated from the peri-ovarian fat and labeled with thymidine analog 5-ethynyl-2-deoxyuridine (EdU). Twenty stress urinary incontinence rats received peri-urethral injection of phosphate-buffered saline as the negative controls and the other 20 stress urinary incontinence rats received peri-urethral injection of EdU-labeled ADSCc. Twenty control rats underwent sham ovariectomy without balloon dilation and served as positive controls. Four weeks later, voiding function was assessed by cystometry. Urethral histologic examination (Masson trichrome stain, picrosirius red stain, Hart elastin stain, Gordon and Sweet stain, and immunohistochemical stain) and Western blot were performed on urethral tissues. RESULTS Both leak point pressure and bladder capacity were significantly increased in ADSC-treated rats, compared to the balloon-injured ovariectomized rats. Histologic examination revealed normalized appearance of the fibromuscular structure of the urethra as well as increased peri-urethral blood vessel density in ADSC-treated rats. On Western blot, vascular endothelial growth factor and P-extracellular signal-regulated kinases (ERKs)1/2 protein was expressed at a higher rate in tissues from ADSC-treated rats compared to phosphate-buffered saline-treated rats. CONCLUSION Peri-urethral injection of ADSCs is associated with more normal urinary function and urethral structure in rats with parturition-related incontinence. The activation of vascular endothelial growth factor and ERK1/2 may be responsible for the paracrine effects from ADSCs.

Al-Ghorab Shunt plus intracavernous tunneling for prolonged ischemic priapism.

To investigate the efficacy and safety of the corpus cavernosum-corpus spongiosum shunt (Al-Ghorab Shunt) plus intracavernous tunneling (CC-CSS+ICT) for prolonged ischemic priapism (PIP). Twelve patients with PIP were enrolled in this study. The mean age of patients was 38.3 ± 9.2 years old and the mean duration of PIP was 2.8 ± 1.0 days (range, 1.5-4 days). All patients received CC-CSS+ICT for treating PIP. The penile hardness score (PHS) and pain visual analogue score (PVAS) were used to assess the efficacy of the surgery 1, 3, and 5 days after surgery. Color duplex Doppler ultrasonography, International Index of Erectile Function, and quality of life (QOL) were used for evaluating penile morphology, erectile function, QOL, and response to sildenafil treatment. The mean duration of follow up was 21.6 ± 10.1 months. Penile detumescence was successfully restored for all 12 patients postsurgery, with the mean PHS and PVAS significantly decreased compared with that presurgery at different time points (1, 3, 5 days postsurgery; P < .001). The cavernosal arterial blood flow observed with the mean PSV at 1, 3, and 5 days postoperation were 17.79 ± 2.04, 19.14 ± 1.58, and 7.73 ± 2.02 cm/s respectively. All patients suffered from corpus cavernosum fibrosis and erectile dysfunction postoperation; only 2 cases (16.7%) with a short duration of PIP (1.5 days) showed response to sildenafil treatment, and 3 cases (25.0%) with severe fibrosis were satisfied with sexual life after excision of penile corpus cavernosum scar and penile prosthesis implantation. The CC-CSS+ICT could quickly reduce penile rigidity and pain for improving the symptoms of PIP and suggests a safe and effective therapeutic method for PIP.