Expression Levels Of Nerve Growth Factor Research Articles

Synergetic Induction of NGF With Diazoxide and Erythropoietin Attenuates Spinal Cord Ischemic Injury

BackgroundParaplegia remains a significant complication of thoracoabdominal aortic intervention. We previously reported that diazoxide (DZ), enhances the neuroprotective efficacy of erythropoietin (EPO). We hypothesized that DZ and EPO combined treatment attenuates spinal cord ischemic injury through upregulation of nerve growth factor (NGF). MethodsDZ (pretreatment) was given to adult male C57/BL6 mice by oral gavage and EPO (before surgery) was intraperitoneally injected 32 h after administration of DZ. Spinal cords were harvested 0, 2, 4, and 6 h after injection of EPO. NGF expression was analyzed by western blot. After determining the optimal time, NGF expression was compared between DZ (pretreatment) + EPO (before surgery), DZ + PBS, PBS + EPO, and PBS + PBS (ischemic control). Four groups were studied to compare the motor function after ischemia: DZ + EPO (n = 11), ischemic control (n = 9), DZ + EPO + tropomyosin receptor kinase A receptor inhibitor (n = 9), and sham (without cross-clamp, n = 4). Spinal cord ischemia was induced by a 4-min thoracic aortic cross-clamp. Functional scoring (Basso Mouse Score) was done at 12-h intervals until 48 h, and spinal cords were harvested for evaluation of NGF expression and histological changes. ResultsNGF expression was significantly upregulated 4 h after administration of EPO. At 4 h after injection of EPO, NGF expression in the DZ + EPO group was significantly higher than that in the other groups. DZ + EPO significantly preserved motor function compared with all other groups. At 48 h after reperfusion, the level of NGF expression in the DZ + EPO group, was significantly higher than in all other groups. ConclusionsDZ + EPO attenuates spinal cord ischemic injury through upregulation of NGF. Better understanding of this mechanism may serve to further prevent ischemic complications for aortic intervention.

Abstract 424: Knockdown of Nerve Growth Factor in Spinal Cord Reduces Myocardial Reperfusion Injury by Suppressing Ischemic Nociceptive Signaling Transmission

Objective: To test the hypothesis that nerve growth factor (NGF) sensitized spinal cardiac afferent activity contributes to myocardial ischemia-reperfusion injury (IRI). Methods and Results: The expression levels of NGF were increased in both dorsal root ganglion (DRG) and spinal cord after myocardial IRI in rats. Whole-cell patch clamp in cultured DRG neurons revealed that NGF aggravated capsaicin-induced current which was eliminated by the transient receptor potential vanilloid 1 (TRPV1) antagonist. Intrathecal injection of lentivirus-mediated NGF shRNA into thoracic T1-T8 segments successfully suppressed NGF mRNA and protein levels. Knockdown of NGF in spinal cord significantly limited IRI-induced infarct size, lowered down the concentration of cardiac troponin I (cTnI), and improved arrhythmia score. NGF gene suppression markedly reduced IRI-caused elevation of NGF and its receptor tropomyosin receptor kinase A (TrkA), TRPV1 and phosphorylated TRPV1. The activation of protein kinase B (Akt) and extracellular signal-regulated kinase (ERK) was also inhibited by NGF shRNA. Upon immunofluorescence staining, substance P (SP) and calcitonin gene-related peptide (CGRP) were found strongly stained in DRG and spinal dorsal horn following myocardial IRI, while these immunoreactive staining were repressed due to NGF gene knockdown. Conclusions: NGF aggravated spinal cardiac afferent nerves activity by sensitizing TRPV1-mediated nociceptive signal transmission. Inhibition of spinal NGF expression effectively protected the heart from myocardial IRI, which may imply a new potential therapeutic approach in ischemic heart diseases.

Nerve growth factor and substance P may be involved in moist exposed burn ointment-mediated chronic refractory wound healing.

Moist exposed burn ointment (MEBO) is becoming increasingly popular in China as it shortens wound-healing time and reduces scar formation. However, its exact mechanism in mediating the wound-healing process is not yet clear. In the present study a total of 90 healthy adult male Wistar rats of specific-pathogen-free grade were divided equally into a control group, wound group, MEBO group, recombinant bovine basic fibroblast growth factor (rb-bFGF) group and sham operation group. Wound healing was observed from the extracted granulation tissues and recorded at three time points on 3, 7 and 14 days. Different levels of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) in tissue homogenate were detected using ELISA. Western blot analysis and quantitative PCR were used to detect the expression of nerve growth factor (NGF), substance P (SP) as well as tyrosine kinase A (TrkA) receptor protein and the corresponding mRNA levels in granulation tissue. It was observed that the wound healing progressed faster in the MEBO and rb-bFGF groups compared with the wound group (P<0.01). TNF-α and IL-6 had an upward-downward trend at three time points, with the wound group demonstrating the most obvious increase (P<0.01). NGF and SP mRNA and protein levels in granulation tissue in MEBO, rb-bFGF and sham operation groups reached their highest levels on day 7 and then decreased on day 14. The expression level of TrkA was also measured simultaneously and its expression pattern was similar to that of NGF and SP. These results suggested that MEBO may promote nerve repair and accelerate wound healing through mediating the expression levels of NGF and SP, as well as TrkA.

Anti-nerve growth factor antibody improves airway hyperresponsiveness by down-regulating RhoA

ABSTRACTBackground: The pathogenesis of asthma is complex and continues to be considered as a challenging subject. Some studies have shown that nerve growth factor (NGF) participates in the pathogenesis of asthma, but the mechanism of airway contraction caused by NGF is still unclear. Objective: Our aim was to discuss the effect of anti-NGF antibody on RhoA expression, and further explore the role of NGF in airway hyperresponsiveness (AHR). Methods: Thirty female BALB/c mice were divided into three groups randomly: control group (group C, n = 10), asthma group (group A, n = 10) and anti-NGF antibody intervention group (group N, n = 10). The asthmatic mice were stimulated by OVA suspension, the intervention mice were given nasal instillation of anti-NGF antibody before the stimulation. Airway responsiveness, eosinophils, IL-13, IFN-γ were measured. The protein expression and mRNA level of NGF and RhoA were detected by immunohistochemical and Real Time-PCR (RT-PCR) analyses. Results: Airway responsiveness, eosinophils and IL-13 levels in group A were significantly increased compare with the other groups, and significantly decreased in group N than those in group A. IFN-γ level was significantly reduced in group A and increased in group N. Immunohistochemistry and RT-PCR analyses showed that the protein expression and mRNA level of NGF and RhoA were significantly increased in group A and significantly decreased in group N. Conclusion: NGF participates in the pathogenesis of asthma in mice. Anti-NGF antibody can inhibit airway inflammation and alleviate AHR by down-regulating the protein expression and mRNA level of RhoA.

Vildagliptin, a DPP4 inhibitor, alleviates diabetes-associated cognitive deficits by decreasing the levels of apoptosis-related proteins in the rat hippocampus.

Cognitive impairment is a prevalent but underestimated complication of diabetes, which can cause spatial memory and learning deficits. In the present study, a streptozotocin-induced type 2 diabetic rat model was employed to investigate the effects of vildagliptin, a new oral hypoglycemic agent that acts by inhibiting dipeptidyl peptidase-4, on diabetes-associated cognitive impairments, as well as the molecular mechanisms involved. The present findings demonstrated that vildagliptin treatment prevented memory impairment and decreased the apoptosis of hippocampal neurons. It also attenuated the abnormal expression of caspase-3, B cell lymphoma-2 (Bcl-2) and Bcl-2 associated X protein in the diabetic model. Vildagliptin treatment also reversed diabetes-induced decreases in phosphorylated (p)-protein kinase B (Akt) and p-glycogen synthase kinase 3β (GSK3β), brain-derived neurotrophic factor and nerve growth factor expression levels. The results indicated that the administration of vildagliptin exerts a protective effect against cognitive deficits by decreasing the expression of apoptosis-related proteins in the hippocampus and that this protective effect was mediated via the Akt/GSK3β signaling pathway.

Therapeutic effects of liver soothingpingchuanformula decoction on experimental asthma in BALB/c mice via regulation of nerve growth factor-tyrosine kinase A pathway.

The present study was designed to investigate the effects of liver soothing pingchuan formula decoction (LSPF) on experimental asthma in BALB/c mice and explore its potential molecular mechanisms. An animal model of asthma was established in BALB/c mice through sensitization and activation with intraperitoneal injection of 10% ovalbumin (OVA)/Al(OH)3 solution in addition to inhalation of a 5% OVA solution. LSPF (300 and 600 mg/kg/day) was initially administered orally prior to activation. Following this, bronchoalveolar lavage fluid (BALF) and lung tissues were collected for histopathalogical examination. Levels of inflammatory cells and cytokines were determined in the BALF, and levels of nerve growth factor (NGF) and tyrosine kinase A (TrkA) in the lung tissues were determined. The results of the present study indicated that increased inflammatory reactions were observed following OVA sensitization (P<0.05), and the expression levels of NGF (P<0.05) and TrkA (P<0.05) were significantly increased, compared with normal mice. Notably, compared with the asthma model group, immunohistochemical results revealed that LSPF treatment suppressed OVA induced inflammatory reactions (P<0.05) and NGF (P<0.05) and TrkA expression levels (P<0.05). In addition, the NGF (P<0.05) and TrkA (P<0.05) were revealed to be downregulated with LSPF treatment from the results of the ELISA and western blotting assay. Overall, the results of the present study demonstrated that LSPF exhibits therapeutic effects on experimental asthma in mice, via downregulation of the NGF-TrkA pathway.

Effects of gangliosides on expressions of caspase-3 and NGF in rats with acute spinal cord injury.

To investigate the effects of ganglioside [monostalotetra-hexosylganglioside (GM1)] on the expressions of caspase-3 and nerve growth factor (NGF) in rats with acute spinal cord injury (SCI). Male Sprague- Dawley (SD) rats were selected and randomly divided into Sham group, SCI group and GM1 administration group. The rats in Sham group, SCI group and GM1 group were subjected to behavioral examinations of Basso Beattie Bresnahan (BBB) and oblique-plate test at 1, 7 and 14 d after operation. The content of methylene dioxyamphetamine (MDA) and the activity of superoxide dismutase (SOD) of every rat in each group were measured by enzyme-linked immunosorbent assay (ELISA). Immunofluorescence staining assay was used to detect the expression levels of caspase-3 and NGF of rats in each group. The messenger ribonucleic acid (mRNA) and protein expressions of caspase-3 and NGF of rats in Sham group, SCI group and GM1 group were detected using reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting assay. The BBB scores and the results of oblique-plate test in Sham group, SCI group and GM1 group at 1, 7 and 14 d showed that the BBB scores and the results of oblique-plate test of rats in each group were significantly decreased at 1 d after SCI, and had different degrees of recovery at 7 and 14 d after injury. The results of ELISA detection revealed that SCI group had increased content of MDA and clearly decreased activity of SOD in comparison with Sham group; at the same time, MDA content in GM1 group was overtly lower than that in SCI group, while SOD activity was enhanced evidently in GM1 group compared with that in SCI group. According to immunofluorescence assay, significantly increased expression of caspase-3 and distinctly decreased expression of NGF were found in SCI group. However, this phenomenon was significantly reversed by GM1. RT-PCR and Western blotting assay severally proved that the mRNA and protein expressions of caspase-3 were raised in SCI group and decreased clearly after the administration of GM1; while the mRNA and protein expressions of NGF was significantly reduced in SCI group and overtly elevated after the administration of GM1. ANOVA showed that there were statistically significant differences in expressions of caspase-3 and NGF among Sham group, SCI group and GM1 group (p<0.05). GM1 has an evident effect on the expressions of caspase-3 and NGF in rats with acute SCI, and is able to down-regulate the expression of caspase-3 and up-regulate the expression of NGF, so as to achieve its therapeutic effect on SCI.

Exenatide upregulates gene expression of glucagon-like peptide-1 receptor and nerve growth factor in streptozotocin/nicotinamide-induced diabetic mice.

Glucagon-like peptide-1 (GLP-1) is an incretin hormone that has modulating effects on insulin release. GLP-1 and receptors for GLP-1 are widely expressed throughout the body including the brain. The expression of GLP-1 receptors is very specific to large neurons in hippocampus, neocortex, and cerebellum. GLP-1 receptor stimulation enhances glucose-dependent insulin secretion and lowers blood glucose in type 2 diabetes mellitus. Studies on adipobiology of neurotrophins have focused on nerve growth factor (NGF) as an example of adipose-derived neurotrophins. Compromised trophic factor signaling may underlie neurodegenerative diseases ranging from Alzheimer's disease to diabetic neuropathies. Exenatide, a potent and selective agonist for the GLP-1 receptor, is currently approved for the treatment of type 2 diabetes mellitus. The aim of this study was to assess the effect of chronic exenatide treatment on the hippocampal gene expression levels of GLP-1 receptor and NGF in diabetic mice. The effects of chronic exenatide treatment (0.1 μg/kg, s.c., twice daily for 2 weeks) on GLP-1 receptor and NGF gene expression levels in the hippocampus of streptozotocin/nicotinamide (STZ-NA)-induced diabetic mice were assessed by quantitative real-time polymerase chain reaction (RT-PCR). The results of this study revealed that hippocampal gene expression of GLP-1 receptor and NGF were downregulated in diabetic mice. Importantly, a significant increase in the gene expression level of GLP-1 receptor and NGF was determined after 2 weeks of exenatide administration. Increased gene expression level of GLP-1 receptor and NGF may underlie the beneficial action of exenatide in STZ/NA-induced diabetes.

Effects of SCN9A gene modification on Na+ channel and the expression of nerve growth factor in a rat model of diarrhea‑predominant irritable bowel syndrome.

The aim of the present study was to identify whether the sodium voltage-gated channel alpha subunit9 (SCN9A) gene modification is a potential treatment for diarrhea‑predominant irritable bowel syndrome (D‑IBS), via regulating the Na+ channel and the expression of nerve growth factor (NGF). The recombinant adenovirus vector of the SCN9A gene was established, and rat colon cells were isolated for SCN9A gene modification. All subjects were divided into four groups: i) The SCN9A‑modified (D‑IBS rat model implanted with SCN9A‑modified colon cells), ii)negative control (NC; D‑IBS rat model implanted with colon cells without SCN9A gene modification), iii) blank (D‑IBS rat model without any treatment) and iv) normal (normal rats without any treatment). Western blotting and reverse transcription‑quantitative polymerase chain reaction were used to detect the protein and mRNA expression levels of SCN9A, NGF and voltage gated sodium channels (Nav)1.8 and Nav1.9 in rat colon tissues. Compared with the normal group, the rats in the SCN9A, NC and blank groups had significantly elevated mRNA and protein expression levels of NGF, SCN9A, Nav1.8 and Nav1.9. The rats in the SCN9A group demonstrated significantly increased mRNA and protein expression levels of NGF, SCN9A, Nav1.8 and Nav1.9 compared with the NC group and the blank group (all P<0.05). SCN9A gene modification can promote the expression of Nav1.8 and Nav1.9 channels, in addition to NGF which may provide a novel therapeutic basis for treating of D‑IBS.

Butyrate promotes visceral hypersensitivity in an IBS-like model via enteric glial cell-derived nerve growth factor.

Altered visceral sensation is common in irritable bowel syndrome (IBS) and nerve growth factor (NGF) participates in visceral pain development. Sodium butyrate (NaB) could induce colonic hypersensitivity via peripheral up-regulation of NGF in animals. Enteric glial cells (EGCs) appear to be an important source of NGF. Whether butyrate could induce visceral hypersensitivity via increased EGC-derived NGF is still unknown. CRL-2690 cells were used for transcriptome analyses after butyrate treatment. Rats received butyrate enemas to induce colonic hypersensitivity. Colorectal distention test was performed to assess visceral sensitivity. Immunofluorescence studies were used to evaluate the co-expression of glial fibrillary acidic protein (GFAP) and NGF or growth associated protein 43 in animal model. NGF expression in rat colon was also investigated. In vitro, CRL-2690 cells were stimulated with NaB or trichostatin A (TSA). NGF or GFAP expression was also examined. Transcriptome analyses showed that butyrate induced marked changes of genes expression related to neurotrophic signaling pathways. NaB-treated rats showed increased visceral sensitivity. An improved NGF expression level was observed in NaB-treated rats. Meanwhile, a 2.1-fold increase in co-expression of GFAP and NGF was also determined in rats received NaB enemas. In cultured cells, both NaB and TSA treatment could cause obvious NGF expression. Thus, butyrate might regulate EGC function via histone deacetylase inhibition. Butyrate-EGC interplay may play a pivotal role in regulation of NGF expression and the development of colonic hypersensitivity in IBS-like animal model.

Correlation among Inflammatory Cytokine Expression Levels, Degree of Disk Degeneration, and Predominant Clinical Symptoms in Patients with Degenerated Intervertebral Discs

Study DesignObservational study.PurposeTo assess the correlation among inflammatory cytokine expression levels, degree of intervertebral disk (IVD) degeneration, and predominant clinical symptoms observed in degenerative disk disease (DDD).Overview of LiteratureLow back pain (LBP) is associated with inflammatory cytokine expression levels, including those of tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and nerve growth factor (NGF). However, the association between cytokine expression levels and the physiological mechanisms of disk degeneration and clinical pain remain controversial.MethodsUsing the enzyme-linked immunosorbent assay, TNF-α, IL-6, and NGF expression levels were analyzed in 58 IVD samples that were harvested from patients with lumbar DDD. Patient samples were grouped according to the degree of IVD degeneration using the Pfirrmann grading system and magnetic resonance imaging, and the correlations between the disease groups and each cytokine expression level were assessed. In addition, on the basis of their predominant preoperative symptoms, the patients were assigned to either an LBP or leg pain group to determine the correlation among these disease manifestations and individual cytokine expression levels.ResultsA gradual increase in TNF-α (R=0.391) and IL-6 (R=0.388) expression levels correlated with the degree of IVD degeneration, whereas NGF (R=0.164) expression levels exhibited a minimal decrease with disease progression. Regarding the predominant clinical manifestation, only the LBP group exhibited a significant increase in TNF-α expression levels (p=0.002).ConclusionsThese results suggested that TNF-α and IL-6 play an important role in the pathophysiology of IVD degeneration at any stage, whereas NGF plays an important role during the early disease stages. Moreover, because TNF-α expression levels were significantly high in the LBP group, we propose that they are involved in LBP onset or progression.

Connexin 43 is involved in the sympathetic atrial fibrillation in canine and canine atrial myocytes

Objective:Atrial fibrillation (AF) is the most common rapid cardiac arrhythmia associated with high morbidity and mortality. Stimulation of the sympathetic nerve is involved in AF occurrence. The gap junction protein connexin 43 (Cx43) plays a key role in electrical conduction velocity in cardiac tissues, and under expression of Cx43 was linked with AF. The aim of this study was to investigate whether Cx43 was involved in sympathetic AF.Methods:Fifteen dogs were randomly divided into 3 groups (5 in each group). Sympathetic AF was induced in dogs and isolated canine atrial myocytes by isoproterenol (ISO) perfusion and rapid atrium pacing (RAP). The expression levels of nerve growth factor (NGF) and tyrosine hydroxylase (TH) in the atrial tissues were detected using immunohistochemical staining. The transcription and protein expression of Cx43 in the AF cell model was measured. Subsequently, Cx43 was blocked by short interfering (si) RNA in atrial myocytes and the gap junctional inter-cellular communication was detected using the scrape-loading and dye transfer assay.Results:Sympathetic AF was successfully induced by a combination of ISO perfusion and RAP. The expression levels of NGF and TH were increased in the RAP group, and further increased in the RAP + ISO group. Tissue samples from the AF dogs had a lower Cx43 level than those of the control group (p<0.05). The expressions of mRNA and protein of Cx43 in sympathetic AF cell model decreased by 26% and 28%, respectively, when compared with the control group, with p<0.05. Silencing Cx43 in cells by siRNA could also efficiently reduce Cx43 expression. The relative levels of Cx45 mRNA were decreased by 73% compared with unaffected cells. The scrape-loading and dye transfer assay showed that gap junctional intercellular communication was hampered in the sympathetic AF cell model and silencing Cx43 could impede channel conduction.Conclusion:The results suggested that low expression of Cx43 was involved in sympathetic AF by influencing intercellular channel conduction. Intervention of Cx43 expression might be an appealing therapy to sympathetic AF.

Voluntary Running Enhances Hippocampal Proliferation by Increasing Hippocampal NGF, BDNF, and IGF-1

Neurotrophic factors and growth factors are known to have positive effects on hippocampal proliferation. However, previous findings on the effects of these factors on exercise-induced hippocampal proliferation are inconsistent. In this study, we investigated the effects of voluntary running on hippocampal proliferation and the expression levels of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and insulin-like growth factor 1 (IGF-1) in hippocampus. Twenty-four male C57BL/6 mice were randomly divided into four groups: control groups 1 and 2 (C1, n = 6; C2, n = 6) and running groups 1 and 2 (R1, n = 6; R2, n = 6). Mice from C1 and C2 were placed individually in standard cages for eight weeks; mice from R1 and R2 were housed individually in cages with a running wheel for eight weeks. At the fifth week, C1 and R1 mice were injected with BrdU for 7 consecutive days. On the first day of the ninth week, the C1 and R1 mice were anaesthetized and hippocampal neuronal proliferation was assessed using immunohistochemistry; the mice in C2 and R2 were sacrificed to test the expression levels of NGF, BDNF, and IGF-1 mRNA in hippocampus using RT-PCR. The results indicated that voluntary running significantly increased the number of BrdU-positive cells in the dentate gyrus (DG), and significantly upregulated the levels of NGF, BDNF, and IGF-1 mRNA in the hippocampus. In conclusion, our findings indicated that hippocampal proliferation was enhanced by voluntary running, which was associated with increased NGF, BDNF, and IGF-1 mRNA levels in the hippocampus.

Assessing the itching intensity using visual analogue scales in atopic dermatitis patients against the background of a therapy with calcineurin inhibitors

Goal. To assess the effect of topical treatment of atopic dermatitis patients with the 0.1% tacrolimus ointment on the itching intensity and skin expression level of growth factor proteins affecting the intensity of cutaneous innervation. Materials and methods. Fifteen patients suffering from atopic dermatitis underwent treatment with the 0.1% tacrolimus ointment. The SCORAD index was calculated to assess the severity of clinical manifestations. The itching intensity was assessed using a visual analogue scale. The skin expression of nerve growth factors, amphiregulin, semaphorin 3A and PGP9.5 protein (a nerve fiber marker) was assessed by the indirect immunofluorescence method. Results. An increased expression of the nerve growth factor and reduced semaphorin 3A expression levels were noted in the patients’ epidermis; there was an increase in the quantity, mean length and fluorescence intensity of PGP9.5+ nerve fibers. As a result of the treatment, the disease severity and itching intensity were reduced, the nerve growth factor expression level was reduced while semaphorin 3A expression level increased in the epidermis, and the mean length and fluorescence intensity of PGP9.5+ nerve fibers was also reduced. A positive correlation among the itching intensity and nerve growth factor expression level, quantity and mean length of PGP9.5+ nerve fibers in the epidermis was revealed, and negative correlation between the itching intensity and semaphorin 3A expression level in the epidermis was established. Conclusion. Topical treatment with the 0.1% Tacrolimus ointment reduces the itching intensity in atopic dermatitis patients, which is related to the therapy-mediated reduction in the epidermis innervation level, decreased expression of epidermal nerve growth factor and increased semaphorin 3A expression level.

PGE1 Attenuates IL-1β-induced NGF Expression in Human Intervertebral Disc Cells.

In vitro study using isolated human intervertebral disc (IVD) cells. To investigate the effects of prostaglandin (PG)E1 and its orally available derivative limaprost on the regulation of nerve growth factor (NGF) expression and to compare their actions with other prostanoids using interleukin (IL)-1-stimulated human IVD cells. We previously reported that a selective COX-2 inhibitor enhanced, whereas PGE2 suppressed the induction of NGF by IL-1 in human IVD cells, and proposed that PGE2 can suppress NGF expression by a negative feedback mechanism. Isolated human IVD cells were stimulated with IL-1 in the presence or absence of increasing concentrations of PGE2, PGE1, limaprost, PGI2, PGD2, or PGF2α (10-10,000 nM). For some experiments, an E-series prostanoid receptor (EP)4 antagonist (L-161,982) was added prior to the stimulation. NGF expression was determined by real-time polymerase chain reaction and its protein level was quantified by enzyme-linked immunosorbent assay. PGE2, PGE1, and limaprost inhibited the IL-1-mediated induction of NGF in a concentration-dependent manner, with IC50 values of 9.9, 10.6, and 70.9 nM, respectively. PGI2 also suppressed NGF expression but to a much less extent. PGD2, on the other hand, significantly enhanced NGF expression, whereas PGF2α had no effect. Protein expression levels of NGF mirrored its mRNA levels. The suppression of NGF expression by PGE2 and PGE1 was partly reversed by L-161,982. PGE1 and limaprost exhibited a novel pharmacological action that suppresses NGF expression in human IVD cells, and other prostanoids differentially regulated NGF expression. Limaprost has been used to treat patients with lumbar spinal stenosis in Japan and was proved to be effective in relieving symptoms. Our in vitro results may explain, in part, the mechanism of action of limaprost for low back pain. N/A.

Transcriptional expression of inflammatory mediators in various somatosensory relay centers in the brain of rat models of peripheral mononeuropathy and local inflammation

Contradictory results have been reported regarding the role of inflammatory mediators in the central nervous system in mediating neuropathic pain and inflammatory hyperalgesia following peripheral nerve injury or localized inflammation. The present study aims to correlate between the mRNA expression and protein secretion of proinflammatory cytokines and nerve growth factor (NGF), in the dorsal root ganglia (DRGs), spinal cord, brainstem and thalamus, and pain-related behavior in animal models of peripheral mononeuropathy and localized inflammation.Different groups of rats (n=8, each) were subjected to either lesion of the nerves of their hindpaws to induce mononeuropathy or intraplantar injection of endotoxin (ET) and were sacrificed at various time intervals. TNF-α, IL-1β and NGF mRNA expression and protein levels in the various centers involved in processing nociceptive information were determined, by RT-PCR and ELISA. Control groups were either subjected to sham surgery or to saline injection.Mononeuropathy and ET injection produced significant and sustained increases in the mRNA expression and protein levels of TNF-α, IL-1β and NGF in the ipsilateral and contralateral DRGs, spinal cord, and brainstem. No significant and consistent changes in the mRNA expression of cytokines were noticed in the thalamus, while a downregulation of the NGF-mRNA level was observed.The temporal and spatial patterns of the observed changes in mRNA expression of cytokines and NGF are not closely in phase with the observed allodynia and hyperalgesia in the different models, suggesting that the role of these mediators may not be reduced exclusively to the production and maintenance of pain.

Effects of carvedilol reduce conjunctivitis through changes in inflammation, NGF and VEGF levels in a rat model.

Carvedilol is a novel third generation β-blocker that acts as an antagonist of β and α adrenergic receptors, and is able to regulate various cell factors. In addition, it possesses antioxidant activity, is capable of reversing cardiac remodeling effects and has anti-arrhythmic effects. The present study aimed to investigate whether the effects of carvedilol were able to reduce conjunctivitis clinical scores. Initially, 24 Sprague Dawley (SD) rats were randomly divided into three equal groups as follows: Control group, model group and carvedilol group. The model and carvedilol group adult SD rats were injected with lipopolysaccharide (LPS) to induce conjunctivitis. In the carvedilol group, the eight SD rats with LPS-induced conjunctivitis also received 50 mg/kg/day of carvedilol for 4 weeks. Next, the effects carvedilol were assessed utilizing a system of clinical sign scores, and an enzyme-linked immunosorbent assay was used to determine the expression levels of interleukin-1β (IL-1β), IL-6, IL-8 and tumor necrosis factor-α (TNF-α). Finally, nuclear factor-κB (NF-κB), nerve growth factor (NGF) and vascular endothelial growth factor (VEGF) were analyzed by western blotting. Carvedilol was observed to significantly reduce clinical sign scores in a dose-dependent manner (P<0.01), and reduce IL-1β, IL-6, IL-8 and TNF-α expression levels (P<0.01) in the LPS-induced rat model of conjunctivitis. Carvedilol was also able to significantly reduce the protein expression levels of NF-κB, and induce the protein expression levels of NGF and VEGF in the LPS-induced rat model of conjunctivitis (P<0.01). In conclusion, the effects of carvedilol may reduce conjunctivitis clinical scores through inflammation, NGF and VEGF in LPS-induced rat models.

Neurological function following cerebral ischemia/reperfusion is improved by the Ruyi Zhenbao pill in a rats.

The present study aimed to investigate the effect and underlying mechanisms of the Ruyi Zhenbao pill on neurological function following cerebral ischemia/reperfusion in rats. Male Sprague-Dawley rats underwent middle cerebral artery occlusion following reperfusion. The rats received intragastrically either sodium carboxymethyl cellulose (control and model groups) or Ruyi Zhenbao pill at doses of 0.2, 0.4 or 0.8 g/kg. Neurological function was assessed by cylinder, adhesive and beam-walking tests after 14-day Ruyi Zhenbao pill treatment. Neurogenesis and angiogenesis were detected using immunofluorescence staining. The expression levels of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) and vascular endothelial growth factor (VEGF) were determined by enzyme-linked immunosorbent assays. Treatment with 0.4 and 0.8 g/kg Ruyi Zhenbao for 14 days significantly improved neurological function, and increased the number of von Willebrand Factor- and neuronal nuclear antigen-positive cells in the ischemic hemisphere of rats. Ruyi Zhenbao pill treatment also significantly enhanced the expression levels of BDNF, NGF and VEGF in the ischemic hemisphere. The results demonstrated that the Ruyi Zhenbao pill improved neurological function following ischemia in rats. The mechanisms of the Ruyi Zhenbao pill are associated with increasing the expression levels of BDNF, NGF and VEGF, and subsequently promoting neurogenesis and angiogenesis in the ischemic zone.

Progression of itching intensity and expression of growth factor proteins in skin of people suffering from atopic dermatitis under the influence of ultraviolet phototherapy

Study of progression of itching intensity and expression of growth factor proteins in skin of people suffering from atopic dermatitis under the influence of narrowband (311Nm) phototherapy. Material and methods. 30 patients with atopic dermatitis were treated by using narrowband (311Nm) phototherapy. SCORAD index was used to assess the severity of the clinical responses. Itching intensity was assessed using visual analogue scale. Expression of growth factor of nerves, semaphorine-3A, amphiregulin, and PGP9.5, a protein marker for nerve fibers, was investigated by means of indirect immunofluorescence. Results. Increased expression level of nerves growth factor, decreased expression level of semaphorine-3A, and increase in the number, average length and luminous intensity of PGP9.5+ -nerve fibers were found in the patients’ epidermis. Course of narrowband (311 Nm) phototherapy resulted in a decrease of the severity of the disease and itching intensity, and semaphorine-3A expression increase, reduction of number and average length of nerve fibers in the epidermis. A direct correlation relationship between the itching intensity and expression level of nerve growth factor, number and average length of PGP9.5+ -nerve fibers in the epidermis as well as an inverse correlation relationship between itching intensity and expression level of semaphorine-3A in the epidermis were found. Conclusion. Treating patients suffering from atopic dermatitis with narrowband (311 Nm) phototherapy leads to a decrease of the itching intensity associated with a decreased intensity of innervation of the epidermis. This decrease in course of phototherapy is facilitated by decrease of nerve growth factor expression level and increase of semaphorine-3A expression.

Human Adenomyosis Endometrium Stromal Cells Secreting More Nerve Growth Factor: Impact and Effect.

Abnormal expression of nerve growth factor (NGF) was found in adenomyosis (AM). We collected AM foci from patients and eutopic endometrium from non-AM controls. Endometrium stromal cells (ESCs) were cultured. Different levels of 17β-estradiol, tumor necrosis factor (TNF), CoCl2, and H2O2 were added to the culture system separately, then the expression level of NGF in ESCs was detected. After adding different levels of NGF, the proliferation and apoptosis of ESCs and aromatase expression were detected. We found that 17β-estradiol promoted NGF production in AM ESCs but not in control ESCs; TNF promoted NGF production in both AM and control ESCs; and CoCl2 inhibited NGF production in control ESCs, but had no effect in AM ESCs. Nerve growth factor promoted the proliferation and synthesis of aromatase in AM ESCs. In conclusion, locally increased estrogen levels and inflammation may cause increased NGF production in the uterus of patients with AM. Nerve growth factor stimulated the proliferation and increased aromatase expression of ESCs from AM foci, suggesting NGF might contribute to the pathology and etiology of AM.