Introduction Erectile dysfunction (ED) remains a major complication after radical prostatectomy. The use of adipose tissue-derived stem cells (ADSC) has shown promising results for the treatment of ED. However, the mechanisms of action for stem cell therapy remain controversial, with increasing evidence pointing to paracrine pathways. Aim To determine the effects and to identify the mechanism of action of ADSC and ADSC-derived lysate in a rat model of cavernous nerve (CN) crush injury. Methods Thirty-two male Sprague-Dawley rats were randomly divided into four equal groups: one group underwent sham operation, while three groups underwent bilateral CN crush. Crush-injury groups were treated at the time of injury with intracavernous injection of ADSC, lysate, or vehicle only (injured controls). Erectile function was assessed by cavernous nerve electrostimulation at 4 weeks. Penile tissue was collected for histology. Main Outcome Measures Intracavernous pressure increase upon CN stimulation; neuronal nitric oxide synthase (nNOS) content in the dorsal penile nerve; smooth muscle content, collagen content, and number of apoptotic cells in the corpus cavernosum. Results Both ADSC and lysate treatments resulted in significant recovery of erectile function, as compared to vehicle treatment. nNOS content was preserved in both the ADSC and lysate group, with significantly higher expression compared to vehicle-treated animals. There was significantly less fibrosis and a significant preservation of smooth muscle content in the ADSC and lysate groups compared to injured controls. The observed functional improvement after lysate injection supports the hypothesis that ADSC act through release of intracellular preformed substances or by active secretion of certain biomolecules. The underlying mechanism of recovery appears to involve neuron preservation and cytoprotection by inhibition of apoptosis. Conclusions Penile injection of both ADSC and ADSC-derived lysate can improve recovery of erectile function in a rat model of neurogenic erectile dysfunction.

Background-Effective treatment for stress urinary incontinence (SUI) is lacking. This study investigates whether transplantation of adipose tissue-derived stem cells (ADSCs) can treat SUI in a rat model.

Background Intracavernous (IC) injection of stem cells has been shown to ameliorate cavernous-nerve (CN) injury-induced erectile dysfunction (ED). However, the mechanisms of action of adipose-derived stem cells (ADSC) remain unclear. Objectives To investigate the mechanism of action and fate of IC injected ADSC in a rat model of CN crush injury. Design, setting, and participants Sprague-Dawley rats (n = 110) were randomly divided into five groups. Thirty-five rats underwent sham surgery and IC injection of ADSC (n = 25) or vehicle (n = 10). Another 75 rats underwent bilateral CN crush injury and were treated with vehicle or ADSC injected either IC or in the dorsal penile perineural space. At 1, 3, 7 (n = 5), and 28 d (n = 10) postsurgery, penile tissues and major pelvic ganglia (MPG) were harvested for histology. ADSC were labeled with 5-ethynyl-2-deoxyuridine (EdU) before treatment. Rats in the 28-d groups were examined for erectile function prior to tissue harvest. Measurements IC pressure recording on CN electrostimulation, immunohistochemistry of the penis and the MPG, and number of EdU-positive (EdU+) cells in the injection site and the MPG. Results and limitations IC, but not perineural, injection of ADSC resulted in significantly improved erectile function. Significantly more EdU+ ADSC appeared in the MPG of animals with CN injury and IC injection of ADSC compared with those injected perineurally and those in the sham group. One day after crush injury, stromal cell-derived factor-1 (SDF-1) was upregulated in the MPG, providing an incentive for ADSC recruitment toward the MPG. Neuroregeneration was observed in the group that underwent IC injection of ADSC, and IC ADSC treatment had beneficial effects on the smooth muscle/collagen ratio in the corpus cavernosum. Conclusions CN injury upregulates SDF-1 expression in the MPG and thereby attracts intracavernously injected ADSC. At the MPG, ADSC exert neuroregenerative effects on the cell bodies of injured nerves, resulting in enhanced erectile response.

Introduction Impotence, or erectile dysfunction (ED), is a major complication of type-II diabetes, and many diabetic men with ED are refractory to common ED therapies. Aim To determine whether autologous adipose tissue derived stem cells (ADSC) injected into the penis of impotent obese type-II diabetic rats survive and improve erectile function. Main outcome measures Intracorporal pressure (ICP) increase with cavernous nerve (CN) electrostimulation, immunohistochemistry, real-time PCR, and serum glucose and testosterone assays. Methods Twenty-two 10-week old male fatty type-II diabetic ZDF rats underwent weight and blood glucose measurement every 2 weeks. At age 22 weeks, all animals underwent unilateral CN electrostimulation and ICP measurement to confirm impotence, and paragonadal adipose tissue (5 grams) was harvested and digested to yield 1.5 million ADSC. Impotent animals were randomized to ADSC treatment and sham control groups. At age 23 weeks, treatment group animals underwent penile injection of 1.5 million ADSC; control group animals received only PBS. Erectile function studies were repeated at age 26 weeks, followed by harvest of tissue and serum. Results Pre- and post-treatment stimulation ICP increase was significantly different between groups (p<0.002). In the control group, mean (SD) pre- and post-treatment stimulation ICP increase was 33.8 (15.9) and 31.4 (24.3) cmH2O, respectively, whereas in the treatment group they were 27.4 (14.8) and 65.3 (15.4) cmH2O. BrdU-labeled ADSC were observed within corporal tissue of the treatment group. TUNEL staining (p<0.0001) and caspase-3 m-RNA expression (p<0.05) were significantly higher within corporal tissue of control group versus treatment group animals. Conclusion Autologous ADSCs injected into the penis appear to survive and improve erectile function. Autologous ADSC therapy is a promising approach to treat diabetic impotence.

In the injured spinal cord, a glial scar forms and becomes a major obstacle to axonal regeneration. Formation of the glial scar involves migration of astrocytes toward the lesion. Matrix metalloproteinases (MMPs), including MMP-9 and MMP-2, govern cell migration through their ability to degrade constituents of the extracellular matrix. Although MMP-9 is expressed in reactive astrocytes, its involvement in astrocyte migration and formation of a glial scar is unknown. Here we found that spinal cord injured, wild-type mice expressing MMPs developed a more severe glial scar and enhanced expression of chondroitin sulfate proteoglycans, indicative of a more inhibitory environment for axonal regeneration/plasticity, than MMP-9 null mice. To determine if MMP-9 mediates astrocyte migration, we conducted a scratch wound assay using astrocytes cultured from MMP-9 null, MMP-2 null, and wild-type mice. Gelatin zymography confirmed the expression of MMP-9 and MMP-2 in wild-type cultures. MMP-9 null astrocytes and wild-type astrocytes, treated with an MMP-9 inhibitor, exhibited impaired migration relative to untreated wild-type controls. MMP-9 null astrocytes showed abnormalities in the actin cytoskeletal organization and function but no detectable untoward effects on proliferation, cellular viability, or adhesion. Interestingly, MMP-2 null astrocytes showed increased migration, which could be attenuated in the presence of an MMP-9 inhibitor. Collectively, our studies provide explicit evidence that MMP-9 is integral to the formation of an inhibitory glial scar and cytoskeleton-mediated astrocyte migration. MMP-9 may thus be a promising therapeutic target to reduce glial scarring during wound healing after spinal cord injury.

Introduction Hyperlipidemia has been associated with erectile dysfunction (ED) via damage to the cavernous endothelium and nerves. Adipose tissue-derived stem cells (ADSC) have been shown to differentiate into endothelial cells and secrete vasculotrophic and neurotrophic factors. Aim To assess whether ADSC have therapeutic effects on hyperlipidemia-associated ED. Methods Twenty-eight male rats were induced to develop hyperlipidemia with a high fat diet (hyperlipidemic rats, HR). Ten additional male rats were fed a normal diet to serve as controls (normal rats, NR). Five months later, all rats were subjected to ADSC isolation from paragonadal fat. The cells were cultured for one week, labeled with 5-ethynyl-2′-deoxyuridine (EdU), and then injected autologously into the corpus cavernosum of 18 HR. The remaining 10 HR rats were injected with phosphate-buffered saline (PBS). At 3 and 14 days post-transplantation, 4 rats in the HR+ADSC group were sacrificed for tracking of the transplanted cells. At one month post-transplantation, all remaining rats were analyzed for serum biochemistry, erectile function and penile histology. Main Outcome Measures Erectile function was assessed by intracavernous pressure measurement during electrostimulation of the cavernous nerve. Cavernous nerves, endothelium, and smooth muscle were assessed by immunohistochemistry. Results Serum total cholesterol and low-density lipoprotein levels were significantly higher in HR than in NR. High-density lipoprotein level was significantly lower in HR than in NR. Mean intracavernous pressure/mean arterial pressure ratio was significantly lower in HR+PBS than in NR+PBS or HR+ADSC. Neuronal nitric oxide synthase (nNOS)-positive nerve fibers and endothelial cells were fewer in HR+PBS than in HR+ADSC. Smooth muscle content was significantly higher in both HR groups than in NR. Conclusions Hyperlipidemia is associated with abnormalities in both the nerves and endothelium. Treatment with ADSC ameliorates these adverse effects and holds promise as a potential new therapy for ED.

Neuropathic pain and bladder dysfunction represent significant quality-of-life issues for many spinal cord injury patients. Loss of GABAergic tone in the injured spinal cord may contribute to the emergence of these symptoms. Previous studies have shown that transplantation of rodent inhibitory interneuron precursors from the medial ganglionic eminence (MGE) enhances GABAergic signaling in the brain and spinal cord. Here we look at whether transplanted MGE-like cells derived from human embryonic stem cells (hESC-MGEs) can mitigate the pathological effects of spinal cord injury. We find that 6 months after transplantation into injured mouse spinal cords, hESC-MGEs differentiate into GABAergic neuron subtypes and receive synaptic inputs, suggesting functional integration into host spinal cord. Moreover, the transplanted animals show improved bladder function and mitigation of pain-related symptoms. Our results therefore suggest that this approach may be a valuable strategy for ameliorating the adverse effects of spinal cord injury.

Background Intracavernous injection of cultured adipose tissue-derived stem cells (ADSCs) effectively restores erectile function in cavernous nerve (CN) injured rats when administered at the time of injury. However, culturing exposes ADSCs to risks of contamination and dedifferentiation. Furthermore, the acute treatment paradigm precludes selecting the patient subset benefitting from the treatment the most. Objectives To explore the effect of uncultured autologous adipose-derived stromal vascular fraction (SVF) on improving erectile function in a rat model of CN injury when administered at the time of injury or four weeks post-injury. Design, setting, and interventions Sixty-three male Sprague-Dawley rats were randomly divided into three groups: intracavernous injection of saline immediately after CN crush (vehicle), intracavernous injection of SVF immediately after CN crush (immediate-treatment), intracavernous injection of SVF four weeks post-CN crush (delayed-treatment). Twenty-six animals underwent sham surgery (sham). Functional testing and histological analysis were performed 12 weeks post-CN crush or sham surgery. Measurements Intracavernous pressure (ICP) response to CN electrostimulation, histological examination of midpenile cross-sections. Results Intracavernous injection of SVF, either immediately, or four weeks post-CN injury, resulted in significantly increased ICP/mean arterial pressure (MAP) ratios compared with the vehicle-treated group. Both immediate and delayed treatment with SVF significantly increased expression of neuronal nitric oxide synthase (nNOS) and neurofilament (NF) in dorsal penile nerves compared to the vehicle group. Furthermore, smooth muscle content and smooth muscle/collagen ratio within corpus cavernosum were significantly improved in both SVF treatment groups compared to vehicle-treated rats. Conclusions Uncultured autologous SVF injected immediately or 4 weeks post-CN crush improved erectile function, promoted nerve regeneration and prevented fibrosis of the corpus cavernosum following CN injury. The clinical availability of routine SVF isolation devices merits testing autologous SVF therapy in penile rehabilitation studies following radical prostatectomy in the near future.