Nerve Growth Factor mRNA Levels Research Articles

Targeted NGF siRNA delivery attenuates sympathetic nerve sprouting and deteriorates cardiac dysfunction in rats with myocardial infarction.

Nerve growth factor (NGF) is involved in nerve sprouting, hyper-innervation, angiogenesis, anti-apoptosis, and preservation of cardiac function after myocardial infarction (MI). Positively modulating NGF expression may represent a novel pharmacological strategy to improve post-infarction prognosis. In this study, lentivirus encoding NGF short interfering RNA (siRNA) was prepared, and MI was modeled in the rat using left anterior descending coronary artery ligation. Rats were randomly grouped to receive intramyocardial injection of lentiviral solution containing NGF-siRNA (n = 19, MI-SiNGF group), lentiviral solution containing empty vector (n = 18, MI-GFP group) or 0.9% NaCl solution (n = 18, MI-control group), or to receive thoracotomy and pericardiotomy (n = 17, sham-operated group). At 1, 2, 4, and 8 wk after transduction, rats in the MI-control group had higher levels of NGF mRNA and protein than those in the sham-operated group, rats in the MI-GFP group showed similar levels as the MI-control group, and rats in the MI-SiNGF group had lower levels compared to the MI-GFP group, indicating that MI model was successfully established and NGF siRNA effectively inhibited the expression of NGF. At 8 wk, echocardiographic and hemodynamic studies revealed a more severe cardiac dysfunction in the MI-siRNA group compared to the MI-GFP group. Moreover, rats in the MI-siRNA group had lower mRNA and protein expression levels of tyrosine hydroxylase (TH) and growth-associated protein 43-positive nerve fibers (GAP-43) at both the infarcted border and within the non-infarcted left ventricles (LV). NGF silencing also reduced the vascular endothelial growth factor (VEGF) expression and decreased the arteriolar and capillary densities at the infarcted border compared to the MI-GFP group. Histological analysis indicated a large infarcted size in the MI-SiNGF group. These findings suggested that endogenous NGF silencing attenuated sympathetic nerve sprouting and angiogenesis, enlarged the infarct size, aggravated cardiac dysfunction, and potentially contributed to an unfavorable prognosis after MI.

Novel Multi-System Functional Gains via Task Specific Training in Spinal Cord Injured Male Rats

Locomotor training (LT) after spinal cord injury (SCI) is a rehabilitative therapy used to enhance locomotor recovery. There is evidence, primarily anecdotal, also associating LT with improvements in bladder function and reduction in some types of SCI-related pain. In the present study, we determined if a step training paradigm could improve outcome measures of locomotion, bladder function, and pain/allodynia. After a T10 contusive SCI trained animals (adult male Wistar rats), trained animals began quadrupedal step training beginning 2 weeks post-SCI for 1 h/day. End of study experiments (3 months of training) revealed significant changes in limb kinematics, gait, and hindlimb flexor-extensor bursting patterns relative to non-trained controls. Importantly, micturition function, evaluated with terminal transvesical cystometry, was significantly improved in the step trained group (increased voiding efficiency, intercontraction interval, and contraction amplitude). Because both SCI and LT affect neurotrophin signaling, and neurotrophins are involved with post-SCI plasticity in micturition pathways, we measured bladder neurotrophin mRNA. Training regulated the expression of nerve growth factor (NGF) but not BDNF or NT3. Bladder NGF mRNA levels were inversely related to bladder function in the trained group. Monitoring of overground locomotion and neuropathic pain throughout the study revealed significant improvements, beginning after 3 weeks of training, which in both cases remained consistent for the study duration. These novel findings, improving non-locomotor in addition to locomotor functions, demonstrate that step training post-SCI could contribute to multiple quality of life gains, targeting patient-centered high priority deficits.

Nerve growth factor expression and nerve regeneration in monkey corneas after LASIK.

To determine whether changes in cornea nerve growth factor (NGF) protein and gene expression correlate with corneal nerve regeneration after LASIK in rhesus monkeys. Ten rhesus monkeys underwent randomly assigned LASIK procedures to correct -8.0 diopters of myopia in both eyes and two additional monkeys (with no surgery) served as controls. The central corneas of the experimental animals were excised 3 and 7 days and 1, 3, and 6 months after the surgery. Nerve regeneration, NGF mRNA, and protein expression were analyzed by gold chloride staining, real-time polymerase chain reaction, and enzyme-linked immune sorbent assay analysis, respectively. Compared to controls, the LASIK-treated animals had a significantly diminished nerve plexus in the sub-basal region of the cornea at all times after the surgery (P < .001). NGF protein levels decreased significantly on days 3 and 7 after LASIK (P < .001), but returned to control levels 1 month later. NGF mRNA levels increased 5.4-fold on day 3 after the surgery (P < .001), then reduced to two-fold (P < .05) above control levels on day 7 and were back to normal at 3 months and beyond. After LASIK, the changes of early NGF protein and NGF mRNA levels correlated with the density of the corneal nerve plexuses. The results showed that the LASIK procedure in non-human primates was associated with changes in NGF protein and mRNA levels in the cornea. Such changes may be related to the initiation of nerve regeneration and the final recovery of nerve plexuses in the cornea.

Role of nerve growth factor-tyrosine kinase receptor A signaling in paclitaxel-induced peripheral neuropathy in rats

The mechanisms underlying paclitaxel-induced peripheral neuropathy remain unknown. Nerve growth factor (NGF) is a representative neurotrophic factor that maintains neuronal function, promotes survival, and mediates neuropathic pain. We investigated expression levels of NGF and its receptors in the dorsal root ganglia (DRG) and spinal dorsal horn (DH) following paclitaxel treatment. Intraperitoneal (I.P.) administration of paclitaxel induced significant mechanical hypersensitivity and cold allodynia in rats, significantly increased the expression of NGF and its receptor tyrosine kinase receptor A (trkA) in the DRG, and increased NGF expression in the DH. In contrast, paclitaxel treatment did not alter the mRNA levels of NGF or its receptors in the DRG, DH, sciatic nerve, or hindpaw skin. Moreover, expression of NEDD4-2, a negative regulator of trkA, was significantly increased in the DRG of paclitaxel-treated rats. Intrathecal (I.T.) administration of the tyrosine kinase receptor inhibitor k252a significantly alleviated mechanical hypersensitivity in paclitaxel-treated rats. Our results suggest that NGF–trkA signaling is involved in mechanical allodynia in paclitaxel-induced neuropathy.

Maternal micronutrient imbalance alters gene expression of BDNF, NGF, TrkB and CREB in the offspring brain at an adult age

Micronutrients like folate, vitamin B12, and fatty acids which are interlinked in the one carbon cycle play a vital role in mediating epigenetic processes leading to an increased risk for neurodevelopmental disorders in the offspring. Our earlier study demonstrates that a micronutrient imbalanced diet adversely affects docosahexaenoic acid (DHA) and protein levels of neurotrophins like brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the brain and cognition in the offspring by 3 months of age. In this study we attempt to analyze if these effects are a consequence of a change in gene expression of these molecules. Further, we also examined the effect of either a postnatal control diet or a prenatal omega-3 fatty acid supplementation on gene expression in the cortex of the offspring. Pregnant rats were divided into control and five treatment groups at two levels of folic acid (normal and excess folate) in the presence and absence of vitamin B12. Omega-3 fatty acid (eicosapentaenoic acid – EPA+DHA) supplementation was given to vitamin B12 deficient groups. Following delivery, 8 dams from each group were shifted to control diet and remaining continued on the same treatment diet. Our results demonstrate that the imbalanced diet caused a marked reduction in the mRNA levels of BDNF, NGF, TrkB, and cAMP response element-binding protein (CREB). Prenatal omega-3 fatty acid supplementation to the maternal imbalanced diet was able to normalize the mRNA levels of all the above genes. This study demonstrates that a maternal diet imbalanced in micronutrients (folic acid, vitamin B12) influences gene expression of neurotrophins and their signalling molecules and thereby adversely affects the brain of the offspring.

Seasonal changes in expression of nerve growth factor and its receptors TrkA and p75 in the ovary of wild ground squirrel (Citellus dauricus Brandt)

The aim of this study was to investigate the presence of nerve growth factor (NGF) and its receptors tyrosine kinase A (TrkA) and p75 in the ovaries of the wild ground squirrels during the breeding and nonbreeding seasons. In the breeding period, NGF, TrkA and p75 were immunolocalized in granulosa cells, thecal cells, interstitial cells and luteal cells whereas in the nonbreeding period, both of them were detected only in granulosa cells, thecal cells and interstitial cells. Stronger immunostaining of NGF, TrkA and p75 were observed in granulosa cells, thecal cells and interstitial cells in the breeding season compared to the nonbreeding season. Corresponding for the immunohistochemical results, immunoreactivities of NGF and its two receptors were greater in the ovaries of the breeding season then decreased to a relatively low level in the nonbreeding season. The mean mRNA levels of NGF, TrkA and p75 were significantly higher in the breeding season than in the nonbreeding season. In addition, plasma gonadotropins, estradiol-17β and progesterone concentrations were significantly higher in the breeding season than in the nonbreeding season, suggesting that the expression patterns of NGF, and TrkA and p75 were correlated with changes in plasma gonadotropins, estradiol-17β and progesterone concentrations. These results indicated that NGF and its receptors, TrkA and p75 may be involved in the regulation of seasonal changes in the ovarian functions of the wild ground squirrel.

Crosstalk between Delta Opioid Receptor and Nerve Growth Factor Signaling Modulates Neuroprotection and Differentiation in Rodent Cell Models

Both opioid signaling and neurotrophic factor signaling have played an important role in neuroprotection and differentiation in the nervous system. Little is known about whether the crosstalk between these two signaling pathways will affect neuroprotection and differentiation. Previously, we found that nerve growth factor (NGF) could induce expression of the delta opioid receptor gene (Oprd1, dor), mainly through PI3K/Akt/NF-κB signaling in PC12h cells. In this study, using two NGF-responsive rodent cell model systems, PC12h cells and F11 cells, we found the delta opioid neuropeptide [d-Ala2, d-Leu5] enkephalin (DADLE)-mediated neuroprotective effect could be blocked by pharmacological reagents: the delta opioid antagonist naltrindole, PI3K inhibitor LY294002, MAPK inhibitor PD98059, and Trk inhibitor K252a, respectively. Western blot analysis revealed that DADLE activated both the PI3K/Akt and MAPK pathways in the two cell lines. siRNA Oprd1 gene knockdown experiment showed that the upregulation of NGF mRNA level was inhibited with concomitant inhibition of the survival effects of DADLE in the both cell models. siRNA Oprd1 gene knockdown also attenuated the DADLE-mediated neurite outgrowth in PC12h cells as well as phosphorylation of MAPK and Akt in PC12h and F11 cells, respectively. These data together strongly suggest that delta opioid peptide DADLE acts through the NGF-induced functional G protein-coupled Oprd1 to provide its neuroprotective and differentiating effects at least in part by regulating survival and differentiating MAPK and PI3K/Akt signaling pathways in NGF-responsive rodent neuronal cells.

Ethanol- and acetaldehyde-induced cholinergic imbalance in the hippocampus of Aldh2-knockout mice does not affect nerve growth factor or brain-derived neurotrophic factor

Neurotrophins, including nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), play an important role in the maintenance of cholinergic-neuron function. The objective of this study was to investigate whether ethanol (EtOH)- and acetaldehyde (AcH)- induced cholinergic effects would cause neurotrophic alterations in the hippocampus of mice. We used Aldh2 knockout (Aldh2-KO) mice, a model of aldehyde dehydrogenase 2 (ALDH2)-deficiency in humans, to examine the effects of acute administration of EtOH and the role of AcH. Hippocampal slices were collected and the mRNA and protein levels of choline acetyltransferase (ChAT), acetylcholinesterase (AChE), NGF and BDNF were analyzed 30min after the i.p. administration of EtOH (0.5, 1.0, or 2.0g/kg). We show that treatment with 2.0g/kg of EtOH decreased ChAT mRNA and protein levels in Aldh2-KO mice but not in wild-type (WT) mice, which suggests a role for AcH in the mechanism of action of EtOH. The administration of 2.0g/kg of EtOH increased AChE mRNA in both strains of mice. EtOH failed to change the levels of NGF or BDNF at any dose. Aldh2-KO mice exhibited a distinctly lower expression of ChAT and a higher expression of NGF both at mRNA and protein levels in the hippocampus compared with WT mice. Our observations suggest that administration of EtOH and elevated AcH can alter cholinergic markers in the hippocampus of mice, and this effect did not change the levels of NGF or BDNF.

The effect of synthetic oxygen carrier-enriched fibrin hydrogel on Schwann cells under hypoxia condition in vitro

Schwann cell (SC), which plays a key role in peripheral nerve regeneration, is one of the most classic supportive cells in neural tissue engineering. However, the biological activity of SCs seeded in nerve scaffolds decays subsequently due to local hypoxia induced by ischemia. Thus, we aimed to investigate whether a synthetic oxygen carrier-enriched fibrin gel would provide a sustained oxygen release to cultured SCs in vitro for overcoming a temporary (48 h) oxygen deprivation. In this study, perfluorotributylamine (PFTBA)-based oxygen carrying fibrin gel was prepared to provide oxygen for SCs under normoxic or hypoxic conditions. The dissolved oxygen within the culture media was measured by a blood-gas analyzer to quantify the time course of oxygen release from the PFTBA-enriched fibrin gel. SCs were cultured in the presence or absence of PFTBA-enriched fibrin gel under normoxic or hypoxic conditions. The tolerance of SCs to hypoxia was examined by a cell apoptosis assay. The growth of cells was characterized using S-100 staining and a CCK-8 assay. The migration of cells was examined using a Transwell chamber. The mRNA of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), glial cell derived neurotrophic factor (GDNF), neural cell adhesion molecule (N-CAM) and vascular endothelial growth factor (VEGF) in SCs were assayed by RT-PCR. In addition, SCs cultured in 3D PFTBA-enriched hydrogel were characterized by Live/Dead staining and the mRNA levels of BDNF, NGF, GDNF, N-CAM and VEGF were assayed by RT-PCR. The results showed that the PFTBA-enriched fibrin hydrogel was able to promote cell adhesion, migration, and proliferation under hypoxic conditions. Interestingly, PFTBA applied through the fibrin hydrogel dramatically enhanced the mRNA of BDNF, NGF, GDNF, N-CAM and VEGF under hypoxic condition. These findings highlight the possibility of enhancing nerve regeneration in cellular nerve grafts through PFTBA increased neurotropic secretion in SCs.

Differential expression of human placental neurotrophic factors in preterm and term deliveries

Neurotrophic factors such as brain derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are involved in development of the placenta and fetal brain. A series of human and animal studies in our department have shown that micronutrients (folic acid, vitamin B12) and omega 3 fatty acids like DHA are all interlinked in the one carbon cycle. Any alterations in one carbon components will lead to changes in methylation patterns that further affect the gene expression at critical periods of development resulting in complications during pregnancy. This may further contribute to risk for neurodevelopmental disorders in children born preterm. Therefore this study for the first time examines the mRNA levels from preterm and term placentae. A total number of 38 women delivering preterm (<37 weeks gestation) and 37 women delivering at term (=>37 weeks gestation) were recruited. The mRNA levels of BDNF and NGF were analyzed by real time quantitative polymerase chain reaction. Our results indicate that BDNF and NGF mRNA levels were lower in preterm group as compared to term group. There was a positive association of placental BDNF and NGF mRNA levels with cord plasma BDNF and NGF levels. The differential expression of BDNF and NGF gene in preterm placentae may also alter the vascular development in preterm deliveries. Our data suggests that the reduced mRNA levels of BDNF and NGF may possibly be a result of altered epigenetic mechanisms and may have an implication for altered fetal programming in children born preterm.

P75 Neurotrophin Receptor Participates in the Choroidal Antiangiogenic and Apoptotic Effects of T-Lymphocyte–Derived Microparticles

Choroidal neovascularization (CNV) is a major cause of vision loss in which choroidal vessels penetrate the RPE-an important source of growth factors, including nerve growth factor (NGF), whose activation via the p75NTR receptor promotes apoptosis and inhibits angiogenesis. We demonstrated previously that human T-lymphocyte-derived microparticles (LMPs) significantly inhibit angiogenesis in several models of ocular neovascularization. We investigated how LMPs modulate pro- and antiangiogenic microenvironments during choroidal angiogenesis. Antiangiogenic effects of LMPs were investigated using a rat model of choroidal angiogenesis. The impact of LMPs on expression of major angiogenic factors was assessed by real-time quantitative PCR (qPCR). To determine whether p75NTR signalling was implicated in LMPs-induced activities, we used a specific antibody and short hairpin RNA (shRNA) targeting p75NTR. Cellular apoptosis was determined via evaluation of activated caspase-3 and annexin V binding. The LMPs time-dependently inhibited choroidal angiogenesis by more than 64% after 48 hours of treatment. Removal of the RPE from choroidal explants abolished the antiangiogenic effects of LMPs. The mRNA levels of pigment epithelium-derived factor (PEDF) and NGF were increased significantly following LMPs treatment of intact, but not RPE-removed choroids. Downregulation of PEDF and p75NTR significantly blocked the antiangiogenic effects of LMPs. Finally, induction of choroidal endothelial cell apoptosis by LMPs was dependent on p75NTR. We demonstrate for the first time to our knowledge that LMPs markedly inhibit choroidal angiogenesis via mechanisms that are dependent on the integrity of the RPE, and that are mediated largely by the PEDF and proapoptotic activities of p75NTR.

Decreased mRNA and Protein Expression of BDNF, NGF, and their Receptors in the Hippocampus from Suicide: An Analysis in Human Postmortem Brain.

Despite the devastating effect of suicide on numerous lives, there is still a lack of knowledge concerning its neurochemical aspects. There is increasing evidence that brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are involved in the pathophysiology and treatment of depression through binding and activating their cognate receptors TrkB and TrkA respectively. The present study was performed to examine whether the expression profiles of BDNF and/or TrkB as well as NGF and/or TrkA were altered in the hippocampus of postmortem brain of the participants, who had committed suicide and whether these alterations were associated with specific psychopathologic conditions. These studies were performed on the hippocampus of 21 suicide victims and 19 non-psychiatric control individuals. The protein and mRNA levels of BDNF, TrkB, NGF, and TrkA were determined by sandwich enzyme-linked immunosorbent assay, Western blot and reverse transcription-PCR. Given the importance of BDNF and NGF and their cognate receptors in mediating physiological functions, including cell survival and synaptic plasticity, our findings of reduced expression of BDNF, TrkB, NGF, and TrkA on both the protein and mRNA levels of postmortem brains of suicide victims suggest that these molecules may play an important role in the pathophysiological aspects of suicidal behavior.

Metoprolol-Mediated Amelioration of Sympathetic Nerve Sprouting after Myocardial Infarction

Objectives: Systemic or local inflammation causes cardiac nerve sprouting and consequent arrhythmia. Metoprolol can prevent sympathetic nerve remodeling after myocardial infarction (MI), but the underlying mechanism is unclear. In this study, we evaluated the role of metoprolol in ameliorating sympathetic sprouting. Methods: Rabbits underwent ligation of the coronary artery for MI. MI rabbits received metoprolol or saline for 7 days. Immunohistochemistry was used to measure cardiac nerve sprouting and sympathetic innervations. Nuclear factor-κB (NF-κB) DNA binding activity was analyzed by electrophoretic mobility shift assay. The protein levels of NF-κB p65, inhibitor κBa (IκBa) and nerve growth factor (NGF) were detected by Western blot analysis. The mRNA levels of NGF, interleukin-1ß (IL-1ß) and tumor necrosis factor-a (TNF-a) were examined by quantitative real-time PCR. Results: MI rabbits showed nerve sprouting and sympathetic hyperinnervation. In MI rabbits, as compared with saline treatment, metoprolol reduced NF-κB DNA binding activity and NF-κB p65 level, and increased IκBa level. Moreover, metoprolol downregulated IL-1ß, TNF-a and NGF levels, and reduced the density of sympathetic nerve fibers. Conclusions: Metoprolol ameliorates sympathetic nerve sprouting in rabbits after MI and is associated in part with inhibiting NF-κB activity.

NGF induces adult stem Leydig cells to proliferate and differentiate during Leydig cell regeneration

Nerve growth factor (NGF) has been reported to be involved in male reproductive physiology. However, few reports have described the activity of NGF during Leydig cell development. The objective of the present study was to examine the role of NGF during stem-Leydig-cell (SLC) regeneration. We investigated the effects of NGF on Leydig-cell (LC) regeneration by measuring mRNA levels in the adult rat testis after ethane dimethanesulfonate (EDS) treatment. Furthermore, we used the established organ culture model of rat seminiferous tubules to examine the regulation of NGF during SLC proliferation and differentiation using EdU staining, real-time PCR and western blotting. Progenitor Leydig cells (PLCs) and immature Leydig cells (ILCs) were also used to investigate the effects of NGF on LCs at different developmental stages. NGF mRNA levels changed significantly during Leydig-cell regeneration in vivo. In vitro, NGF significantly promoted the proliferation of stem Leydig cells and also induced steroidogenic enzyme gene expression and 3β-HSD protein expression. The data from PLCs and ILCs showed that NGF could increase Cyclin D1 and Hsd 17b3 mRNA levels in PLCs and Cyclin D1 mRNA levels in ILCs. These results indicate that NGF may play an important role during LC regeneration by regulating the proliferation and differentiation of LCs at different developmental stages, from SLCs to PLCs and from PLCs to ILCs. The discovery of this effect of NGF on Leydig cells will provide useful information for developing new potential therapies for PADAM (Partial Androgen Deficiency in the Aging Male).

Growth and expression of rat bone marrow mesenchymal stem cells modified by nerve growth factor in diabetic rat bladders

The aim of the present study was to determine whether rat bone marrow mesenchymal stem cells (MSCs) transfected with the nerve growth factor (NGF) gene and then transplanted into diabetic rat bladder tissues survive and continue to express NGF. A recombinant lentiviral vector carrying the NGF gene was constructed and transfected into rat bone marrow MSCs. BrdU‑labeled immunohistochemistry was used to observe NGF expression in the transfected MSCs. BrdU‑labeled and NGF‑transfected MSCs were transplanted into diabetic rat bladder tissues. BrdU‑labeled immunohistochemistry was used to observe the growth of NGF‑transfected MSCs in the tissue samples. NGF mRNA and protein expression levels in MSCs were analyzed using reverse transcription polymerase chain reaction (RT-PCR) and ELISA, respectively. The recombinant NGF gene lentiviral vector and NGF gene-modified rat bone marrow MSCs were successfully constructed. NGF gene-modified rat MSCs survived in the diabetic rat bladders 4 weeks following injection and NGF gene expression was increased. In the present study, NGF gene-modified MSCs were shown to be capable of survival in diabetic rat bladder tissues and stably expressed NGF.

34 MECHANISMS INDUCING AUTONOMIC DYSREFLEXIA DURING BLADDER DISTENTION IN RATS WITH SPINAL CORD INJURY

You have accessJournal of UrologyUrodynamics/Incontinence/Female Urology: Basic Research (1)1 Apr 201334 MECHANISMS INDUCING AUTONOMIC DYSREFLEXIA DURING BLADDER DISTENTION IN RATS WITH SPINAL CORD INJURY Tsuyoshi Yoshizawa, Satoru Yoshikawa, Ryosuke Takahashi, Satoru Takahashi, and Naoki Yoshimura Tsuyoshi YoshizawaTsuyoshi Yoshizawa Pittsburgh, PA More articles by this author , Satoru YoshikawaSatoru Yoshikawa Pittsburgh, PA More articles by this author , Ryosuke TakahashiRyosuke Takahashi Pittsburgh, PA More articles by this author , Satoru TakahashiSatoru Takahashi Tokyo, Japan More articles by this author , and Naoki YoshimuraNaoki Yoshimura Pittsburgh, PA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.1409AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Autonomic dysreflexia (AD) is a potentially life-threatening medical emergency, and can be induced by viscero-vascular reflexes during bladder distention, resulting in uncontrolled sympathetic activity and hypertension, in patients with spinal cord injury (SCI). This study investigated the mechanisms inducing AD in SCI due to enhanced bladder-to-vascular reflexes in rats, especially focusing on capsaicin-sensitive C-fiber afferents and nerve growth factor (NGF) expression. METHODS SCI was produced by transection of the Th4-5 spinal cord in female rats. After 4 weeks, changes in blood pressure during graded increases in intravesical pressure (20 to 80 cmH2O) were measured in spinal intact (SI) and SCI rats under urethane anesthesia. In some animals, effects of C-fiber desensitization induced by capsaicin-pretreatment (125mg/kg, s.c.) on the bladder-to-vascular reflex were also examined. NGF levels of mucosa and detrusor muscle layers of the bladder, and L6-S1 dorsal root ganglia (DRG) were measured by RT-PCR and ELISA. Patch-clamp recordings were also performed in capsaicin-sensitive bladder afferent neurons dissociated from L6-S1 DRG, which were labeled by Fast Blue injected into the bladder wall. RESULTS In SI and SCI rats, systemic arterial blood pressure was increased in pressure-dependent fashion during increases in intravesical pressure, with blood pressure elevation started at lower intravesical pressure (20 cmH2O) in SCI rats compared to SI rats. In addition, these arterial blood pressure responses to bladder distention were significantly reduced by desensitization of capsaicin-sensitization C-fiber afferent pathways. Patch-clamp recordings showed hyperexcitability of bladder afferent neurons from SCI rats as evidenced by lower thresholds for action potential activation in SCI rats compared to SI rats (−26.4±1.3 vs. −21.8±0.9mV). SCI rats also had higher NGF mRNA and protein levels of the bladder and DRG compared to SI rats. CONCLUSIONS These results indicate that the bladder-to-vascular reflex induced by capsaicin-sensitive C-fiber afferents is enhanced in association with increased NGF expression after SCI, suggesting that suppression of C-fiber bladder afferent activity and/or NGF expression in the bladder could be effective for reducing AD episodes during bladder distention in patients with SCI. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e13-e14 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Tsuyoshi Yoshizawa Pittsburgh, PA More articles by this author Satoru Yoshikawa Pittsburgh, PA More articles by this author Ryosuke Takahashi Pittsburgh, PA More articles by this author Satoru Takahashi Tokyo, Japan More articles by this author Naoki Yoshimura Pittsburgh, PA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Oxytocin Receptor Ligands Induce Changes in Cytoskeleton in Neuroblastoma Cells

Aim of the present study was to evaluate effects of ligands of oxytocin receptors on gene expression of neurofilament proteins (nestin and microtubule-associated protein 2 (MAP2)) associated with neuronal differentiation and growth factors (brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF)) related to neuronal growth. Fluorescent staining of F-actin was used to observe morphology of cells. Co-treatment with oxytocin and oxytocin receptor antagonist--atosiban--resulted in significant increase of MAP2 gene expression in SK-N-SH cells. There was no effect of oxytocin on gene expression of growth factors BDNF and NGF. Surprisingly, oxytocin with atosiban significantly increased mRNA levels for both BDNF and NGF. Gene expression of vasopressin receptor (V1aR) significantly decreased in response to vasopressin. Atosiban decreased mRNA levels for oxytocin receptor (OXTR) and V1aR. Oxytocin significantly decreased OXTR and nestin mRNA levels and increased mRNA levels for BDNF and NGF in U-87 MG cells. The densest recruitment of F-actin filaments was observed in apical parts of filopodia in SK-N-SH cells incubated in oxytocin presence. Present data demonstrate complex role of ligands of oxytocin receptors in regulation of gene expression of intermediate filaments and thus, oxytocin might be considered as a growth factor in neuronal type of cells.

Oncogene‐ and Oxidative Stress‐Induced Cellular Senescence Shows Distinct Expression Patterns of Proinflammatory Cytokines in Vascular Endothelial Cells

Senescent cells are metabolically active and produce a variety of proinflammatory cytokines. It was previously reported that atherosclerotic plaques contain senescent cells, suggesting that senescence may contribute to the progression of atherosclerosis. In this study, we induced cellular senescence in vascular endothelial cells (VECs) using hydrogen peroxide (H2O2) or an adenovirus that expresses a constitutively active mutant of Ras (AdRas12V) and studied the expression of cytokines. Both H2O2 treatment and AdRas12V infection induced senescence in VECs, as assessed by senescence-associated β-Gal activity and the expression of proteins such as p53 and p21CIP1. In addition, both treatments induced the expression of a variety of cytokines, including interleukin-1β (IL-1β) and nerve growth factor (NGF). AdRas12V infection induced IL-1β expression more significantly than H2O2 treatment, whereas both treatments induced comparable mRNA and protein expression levels of NGF. These results suggest that senescent cells express different patterns of proinflammatory cytokines, depending on the trigger that induced senescence. It is therefore possible that senescent cells can differentially induce inflammation in the surrounding tissues, depending on the cause of senescence.

Decreased mRNA and Protein Expression of BDNF, NGF, and their Receptors in the Hippocampus from Suicide: An Analysis in Human Postmortem Brain

Despite the devastating effect of suicide on numerous lives, there is still a lack of knowledge concerning its neurochemical aspects. There is increasing evidence that brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are involved in the pathophysiology and treatment of depression through binding and activating their cognate receptors TrkB and TrkA respectively. The present study was performed to examine whether the expression profiles of BDNF and/or TrkB as well as NGF and/or TrkA were altered in the hippocampus of postmortem brain of the participants, who had committed suicide and whether these alterations were associated with specific psychopathologic conditions. These studies were performed on the hippocampus of 21 suicide victims and 19 non-psychiatric control individuals. The protein and mRNA levels of BDNF, TrkB, NGF, and TrkA were determined by sandwich enzyme-linked immunosorbent assay, Western blot and reverse transcription-PCR. Given the importance of BDNF and NGF and their cognate receptors in mediating physiological functions, including cell survival and synaptic plasticity, our findings of reduced expression of BDNF, TrkB, NGF, and TrkA on both the protein and mRNA levels of postmortem brains of suicide victims suggest that these molecules may play an important role in the pathophysiological aspects of suicidal behavior.

Possible involvement of nerve growth factor in dysmenorrhea and dyspareunia associated with endometriosis

Nerve growth factor (NGF) has been recently proposed as one of the key factors responsible not only for promotion of nerve fiber growth but also for the onset and maintenance of pain in a variety of diseases. The aim of this study was to investigate the role of NGF in the pelvic pain associated with endometriosis. Tissue and peritoneal fluid samples were collected from 95 women with laparoscopically and histopathologically confirmed endometriosis and 59 control women without endometriosis. Expression levels of NGF mRNA and protein were examined using real-time RT-PCR and immunohistochemistry, respectively. Concentration of NGF in the peritoneal fluid (PF-NGF) was measured using ELISA. The degree of dyspareunia and dysmenorrhea was evaluated using a verbal rating scale. Real-time RT-PCR analysis revealed that NGF mRNA was significantly more abundant in the ovarian endometriomas and peritoneal endometriosis than in the normal control endometrium. Immunohistochemical analyses demonstrated that NGF was prominently expressed and preferentially localized to the glands of the ovarian endometriomas and peritoneal endometriosis, whereas it was only weakly detectable in the normal endometrium. Although PF-NGF was undetectable in some normal subjects and endometriosis patients, elevated PF-NGF in the peritoneal fluid was more frequently observed in endometriosis patients with severe pain than in those with less severe pain. Our results suggest that NGF produced locally in the peritoneal cavity may be involved in the generation of endometriosis-associated pelvic pain.