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In response to sustained damage to a kidney, fibrosis that can be characterized as the deposition of a collagenous matrix occurs and consequently causes chronic kidney failure. Because most animals used in experiments synthesize ascorbic acid (AsA) from glucose, the roles of AsA in fibrotic kidney diseases are largely unknown. Unilateral ureteric obstruction (UUO) mimics the complex pathophysiology of chronic obstructive nephropathy and is an ideal model for the investigation of the roles of AsA in kidney failure. We examined the impact of a deficiency of Akr1a, a gene that encodes aldehyde reductase and is responsible for the production of AsA, on fibrotic damage caused by UUO in mice. Oxidatively modified DNA was elevated in wild-type and Akr1a-deficient kidneys as a result of UUO to a similar extent, and was only slightly suppressed by the administration of AsA. Even though Akrla-deficient mice could produce only about 10% of the AsA produced by wild-type mice, no difference was observed in collagen I synthesis under pathological conditions. The data implied either a low demand for AsA or the presence of another electron donor for collagen I production in the mouse kidney. Next, we attempted to elucidate the potential causes for oxidative damage in kidney cells during the fibrotic change. We found decreases in mitochondrial proteins, particularly in electron transport complexes, at the initial stage of the kidney fibrosis. The data imply that a dysfunction of the mitochondria leads to an elevation of ROS, which results in kidney fibrosis by stimulating cellular transformation to myofibroblasts. [ABSTRACT FROM AUTHOR]

A prerequisite for the successful clinical application of gene therapy in erectile dysfunction (ED) is the availability of safe and efficient gene delivery systems. The aim of this study was to examine the effectiveness of guanidinylated bioreducible polymer (GBP) polyplexes for gene delivery systems, which take advantage of the biodegradability of reducible disulfide bonds and the cell-penetrating ability of guanidine groups. For in vitro transfection experiments, we used mouse cavernous endothelial cells and A7r5 rat vascular smooth muscle cells. For in vivo experiments, we used a mouse model of hypercholesterolaemic ED in which 2-month-old male C57BL/6 mice were fed a diet containing 4% cholesterol and 1% cholic acid for 3 months. Animals or cells were treated with pCMV-Luc, poly(ethyleneimine) (PEI)25k/pCMV-Luc polyplex (weight ratio: 1) and GBP/pCMV-Luc polyplexes (weight ratio: 20, 40, 60 and 80). Gene expression was evaluated by luciferase assay, and the gene expression area was evaluated by immunohistochemistry. GBP had greater transfection efficiency as the weight ratio increased. GBP had sevenfold higher gene delivery efficiency in A7r5 cells at a weight ratio of 80 than did PEI25k. Moreover, the gene expression was more profoundly induced by GBP/pCMV-Luc than by pCMV-Luc in both the corpus cavernosum tissue of hypercholesterolaemic mice and in mouse cavernous endothelial cells, although the expression levels induced by the GBP gene delivery system were lower than those induced by the PEI25k gene delivery system. GBP revealed no considerable cytotoxicity to A7r5 cells and mouse cavernous endothelial cells (relative cell viability: 95 and 88% respectively), whereas PEI25k resulted in high cytotoxicity. Interestingly, immunofluorescent double staining revealed that luciferase expression induced by the GBP polyplex mainly overlapped with cavernous endothelial cells, but rarely with smooth muscle cells. The GBP-based non-viral gene expression system may be useful for the development of gene therapy in vasculogenic ED. [ABSTRACT FROM AUTHOR]

Introduction: Radical prostatectomy for prostate cancer not only induces cavernous nerve injury but also causes cavernous angiopathy, which is responsible for poor responsiveness to phosphodiesterase-5 inhibitors. Insulin-like growth factor-binding protein 5 (IGFBP5) promotes cell death and induces apoptosis in various cell types. Objective: To investigate the effectiveness of IGFBP5 knockdown at improving erectile function in a mouse model of cavernous nerve injury. Methods: Eight-week-old C57BL/6 mice were used to prepare cavernous nerve injury model. Mice were divided into 4 groups: a sham operation group and three cavernous nerve injury (CNI) groups, which were administered intracavernous injections of phosphate buffered saline, scrambled control shRNA, or shRNA targeting mouse IGFBP5 (shIGFBP5) lentivirus particles. One week later, we measured erectile function by electrically stimulating the bilateral cavernous nerve. Results: IGFBP5 expression in cavernous tissues were significantly increased in CNI mice compare to sham mice. CNI mice had reduced erectile function, but shIGFBP5 treatment resulted in significant improvements. Furthermore, in CNI mice, numbers of cavernous endothelial cells, pericytes, and neuronal cells were increased by shIGFBP5 treatment. Conclusions: Knockdown of IGFBP5 improved erectile function in CNI mice by enhancing neurovascular regeneration. Local inhibition of IGFBP5 expression may provide a new treatment strategy for the treatment of neurovascular diseases. Disclosure: No. [ABSTRACT FROM AUTHOR]

Introduction: As a peripheral nerve injury disease, cavernous nerve injury (CNI) caused by prostate cancer surgery and other pelvic surgery causes organic damage to cavernous blood vessels and nerves, thereby significantly attenuating the response to phosphodiesterase-5 inhibitors. Objective: Here, we investigated the role of heme-binding protein 1 (Hebp1) in erectile function using a mouse model of bilateral CNI, which is known to promote angiogenesis and improve erection in diabetic mice. Methods: To investigate the efficacy and mechanism of Hebp1 in restoring erectile function in CNI-induced ED mice, we injected recombinant mouse Hebp1 protein into the penis of CNI-induced ED mice. Detailed mechanisms were assessed using Signaling Explorer Antibody Arrays on penile tissue from CNI-induced ED mice; MPG tissue and Schwann cells were cultured in the presence of 2.5 μg/ml LPS. Results: We found a potent neurovascular regenerative effect of Hebp1 in CNI mice, demonstrating that exogenously delivered Hebp1 improved erectile function by promoting the survival of cavernous endothelial-mural cells and neurons. We further found that endogenous Hebp1 delivered by mouse cavernous pericyte (MCP)-derived extracellular vesicles promoted neurovascular regeneration in CNI mice. Moreover, Hebp1 achieved these effects by reducing vascular permeability through regulation of claudin family proteins. Conclusions: Our findings provide new insights into Hebp1 as a neurovascular regeneration factor and demonstrate its potential therapeutic application to various peripheral nerve injuries. Disclosure: No. [ABSTRACT FROM AUTHOR]

In the present study, withdrawal symptoms induced by morphine or β-endorphin administered intracerebroventricularly (i.c.v.) were compared in ICR mice. Naloxone (10 mg/kg) was post-treated intraperitoneally (i.p.) 3 h after either a single or repeated (1 time/day for 3 days) i.c.v. injections with opioids. Withdrawal symptoms such as jumping frequency, diarrhea, weight loss, rearing, penile licking and paw tremor were observed for 30 min immediately after naloxone treatment. Withdrawal symptoms (jumping, diarrhea, weight loss, rearing, penile licking and paw tremor) observed in the group treated with morphine was persistently increased during 3 days. On the other hand, withdrawal symptoms such as diarrhea, weight loss and rearing in β-endorphin-treated group were increased after a single injection with β-endorphin, but gradually decreased after the repeated injection. Furthermore, no jumping behavior, penile licking and paw tremor in β-endorphin-treated group were observed throughout the whole period of time. In addition, the hypothalamic changes of several signal molecules such as pERK, pCaMK-IIα, c-FOS and pCREB expression were observed during the presence or absence of withdrawal responses induced by morphine or β-endorphin administered once or repeatedly. Both hypothalamic pCaMK-IIα and c-FOS expressions were increased by naloxone treatment in acutely administered morphine group, whereas only pCaMK-IIα expression was elevated by naloxone treatment in repeatedly administered morphine group. In contrast with the findings in morphine-treated group, only pCaMK-IIα expression was decreased by naloxone treatment in repeatedly administered β-endorphin group. Our results suggest that profiles of the withdrawal symptoms induced by morphine and β-endorphin administered supraspinally appear to be differentially regulated. The pCaMK-IIα and the c-FOS protein expression may play important roles for the regulation of naloxone-precipitated withdrawal symptoms such as jumping, diarrhea, weight loss, rearing, penile licking and paw tremor induced by morphine-treated group, whereas the phosphorylation of hypothalamic pCaMK-IIα appears to be involved only in the regulation of naloxone-precipitated withdrawal symptoms such as diarrhea, weight loss and rearing in β-endorphin-treated group. [ABSTRACT FROM AUTHOR]