Nerve Growth Factor mRNA Levels Research Articles

Effect of Electroacupuncture at Different Acupoints on Expression of NGF and TrkA in Cerebral Cortex in Rats with Myocardial Ischemia

To compare the therapeutic effect of electroacupuncture (EA) of "Shenmen" (HT 7, Yuan point of the Heart Meridian), "Zhizheng" (SI 7, Luo point of the Small Intestine Meridian) and "Xinshu" (BL15, Back-shu point) on the expression of nerve growth factor (NGF) and its receptor, tyrosine kinase A (TrkA) in the cerebral cortex of myocardial ischemia (MI) rats. A total of 70 male SD rats were randomized into sham operation (sham, n=10), model, HT 7, SI 7, and BL15 groups (n=15 in each of the latter 4 groups). The MI model was established by ligation of the anterior descending branch of the left coronary artery. EA (1 mA, 2 Hz) was respectively applied to HT 7, SI 7 and BL15 for 15 min, once per day for 1 week. Immunohistochemistry and real-time fluorescent quantitative PCR were used to detect the expression of NGF and TrkA proteins and genes in the cerebral cortex. Compared with the sham group, no significant changes were found in the number of NGF immune-reaction (IR)-positive and TrkA IR-positive cells, and the expression levels of NGF mRNA and TrkA mRNA in the model group (P>0.05). After EA intervention, the number of NGF and TrkA IR-positive cells and the expression of NGF mRNA and TrkA mRNA in each of the 3 EA groups were significantly increased relevant to the model group (P<0.01, P<0.05). The effect of EA at BL 15 was significantly superior to that of EA at HT 7 and SI 7 in increasing the number of NGF and TrkA positive cells and up-regulating the expression of their mRNAs (P<0.01, P<0.05). EA at HT 7, SI 7 and BL 15 can increase the levels of expression of NGF and TrkA proteins and mRNAs in the cerebral cortex of subacute MI rats and the effects of EA-BL 15 are obviously superior to those of EA-HT 7 and EA-SI 7, suggesting a relative specificity of the effect of EA at different acupoints.

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.

Neurotrophins and cholinergic enzyme regulated by calpain-2: New insights into neuronal apoptosis induced by polybrominated diphenyl ether-153

Polybrominated diphenyl ether-153 (BDE-153) has been demonstrated to induce neuronal apoptosis in rat cerebral cortex and primary neurons. Neurotrophins and cholinergic enzymes play critical roles in the neuronal survival, maintenance, synaptic plasticity and learning memory, however, their roles in neuronal apoptosis following the BDE-153 treatment remain unclear. In this study, we firstly explored the possible predominant pathway underlying the neuronal apoptotic induced by the BDE-153 treatment in rat cerebral cortex, by measuring expression levels (mRNA and protein) of p53, caspase-3, 8, 9, calpain-1, and calpain-2, detected the levels (protein contents and mRNA) of neurotrophins including brain-derived neurotrophic factor (BDNF), glial-derived neurotrophic factor (GDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3), and neurotrophin-4 (NT-4), and measured acetylcholinesterase (AchE) and choline acetyltransferase (ChaT) activities in rat cerebral cortex and primary neurons following BDE-153 treatment with or without pretreatment with inhibitors. Results showed that the neuronal apoptosis induced by BDE-153 was dependent on p53, and dependent on more calpain-2 than caspase-3 in the cerebral cortex of rats. Following the BDE-153 treatment, the protein contents and mRNA levels of BDNF, GDNF, NGF, NT-3, and NT-4, as well as the AchE and ChaT activities were significantly decreased in the cerebral cortex and primary neurons when compared to the untreated group. When pretreated primary neurons with calpain inhibitor PD150606 or cyclin-dependent kinase (cdk5, the downstream complex of calpain) inhibitor Roscovitine, the neurotrophins contents and activities of ChaT and AchE were reverted, along with the improvement of neuron survival compared with BDE-153 treatment alone. We conclude that neurotrophins and cholinergic enzymes were regulated by the calpain-2 activation and its downstream cdk5 pathway, and which was involved in the neuronal apoptosis induced by the BDE-153 treatment.

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.

Angiotensin-(1-7) attenuates atrial tachycardia-induced sympathetic nerve remodeling.

Introduction:The effect of Angiotensin-(1–7) (Ang-(1–7)) on atrial autonomic remodeling is still unknown. We hypothesized that Ang-(1–7) could inhibit sympathetic nerve remodeling in a canine model of chronic atrial tachycardia.Materials and methods:Eighteen dogs were randomly assigned to sham group, pacing group and Ang-(1–7) group. Rapid atrial pacing was maintained for 14 days in the pacing and Ang-(1–7) groups. Ang-(1–7) was administered intravenously in the Ang-(1–7) group. The atrial effective refractory period and atrial fibrillation inducibility level were measured at baseline and under sympathetic nerve stimulation after 14 days of measurement. The atrial sympathetic nerves labeled with tyrosine hydroxylase were detected using immunohistochemistry and Western blotting, and tyrosine hydroxylase and nerve growth factor mRNA levels were measured by reverse transcription polymerase chain reaction.Results:Pacing shortened the atrial effective refractory period and increased the atrial fibrillation inducibility level at baseline and under sympathetic nerve stimulation. Ang-(1–7) treatment attenuated the shortening of the atrial effective refractory period and the increase in the atrial fibrillation inducibility level. Immunohistochemistry and Western blotting showed sympathetic nerve hyperinnervation in the pacing group, while Ang-(1–7) attenuated sympathetic nerve proliferation. Ang-(1–7) alleviated the pacing-induced increases in tyrosine hydroxylase and nerve growth factor mRNA expression levels.Conclusion:Ang-(1–7) can attenuate pacing-induced atrial sympathetic hyperinnervation.

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.

Does Endurance Training Compensate for Neurotrophin Deficiency Following Diabetic Neuropathy?

BackgroundA lack of neurotrophic support is believed to contribute to the development of diabetic neuropathy. On the other hand, neurotrophins have consistently been shown to increase in the central and peripheral nervous system following exercise, but the effects of exercise intervention on brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in diabetic neuropathy are not understood.ObjectivesThis experimental study was designed and carried out at the Tarbiat Modares university (TMU) in Tehran, Iran, to investigate the hypothesis that increased activity as endurance training can help to increase the endogenous expression of neurotrophins in diabetic rats.MethodsThis was an experimental study with 2 × 2 factorial plans performed at TMU in Iran. Sampling was accidental and 28 adult male Wistar rats in the body mass range of 326.3 ± 8.4 g comprised the sample, with each rat randomly assigned to four groups: diabetic control (DC), diabetic training (DT), healthy control (HC), and healthy training (HT). To induce diabetic neuropathy, after 12 hours of food deprivation, an intraperitoneal injection of streptozotocin (STZ) solution (45 mg/Kg) method was used. Two weeks after STZ injection, the endurance training protocol was performed for 6 weeks; 24 hours after the last training session, the rats were sacrificed. Real-time PCR was used for BDNF and NGF expression.ResultsThe data indicate that diabetes decreases BDNF and NGF expression in sensory (92%, P = 0.01; 90%, P = 0.038, respectively) and motor (93%, P = 0.05; 60%, P = 0.029, respectively) roots. However, NGF mRNA levels in the DT group were significantly higher than in the HC group ((7.1-fold), P = 0.01; (2.2-fold), P = 0.001, respectively, for sensory and motor roots), but this was not shown for BDNF. In addition, endurance training can increase NGF expression in healthy rats ((7.4-fold), P = 0.01; (3.8-fold), P = 0.001, respectively, for sensory and motor roots).ConclusionsThis study shows that BDNF and NGF expression decreases in diabetic neuropathy. However, this decrease can be reversed through endurance training. These results also indicate that endurance training may have a potential role in compensating for neurotrophin deficiency following diabetic neuropathy.

Genome-wide association study of aggressive behaviour in chicken.

In the poultry industry, aggressive behaviour is a large animal welfare issue all over the world. To date, little is known about the underlying genetics of the aggressive behaviour. Here, we performed a genome-wide association study (GWAS) to explore the genetic mechanism associated with aggressive behaviour in chickens. The GWAS results showed that a total of 33 SNPs were associated with aggressive behaviour traits (P < 4.6E-6). rs312463697 on chromosome 4 was significantly associated with aggression (P = 2.10905E-07), and it was in the intron region of the sortilin-related VPS10 domain containing receptor 2 (SORCS2) gene. In addition, biological function analysis of the nearest 26 genes around the significant SNPs was performed with Ingenuity Pathway Analysis. An interaction network contained 17 genes was obtained and SORCS2 was involved in this network, interacted with nerve growth factor (NGF), nerve growth factor receptor (NGFR), dopa decarboxylase (L-dopa) and dopamine. After knockdown of SORCS2, the mRNA levels of NGF, L-dopa and dopamine receptor genes DRD1, DRD2, DRD3 and DRD4 were significantly decreased (P < 0.05). In summary, our data indicated that SORCS2 might play an important role in chicken aggressive behaviour through the regulation of dopaminergic pathways and NGF.

Atorvastatin attenuates sympathetic hyperinnervation together with the augmentation of M2 macrophages in rats postmyocardial infarction.

Inflammation after myocardial infarction (MI) causes cardiac nerve sprouting and consequent ventricular arrhythmias (VAs). Macrophages, as major immune cells, are involved in the entire inflammation response process and serve as a link between inflammation and sympathetic hyperinnervation by regulating nerve growth factor (NGF) expression. Accumulating evidence shows that statins possess antiarrhythmogenic properties, and the aim of this study was to explore the mechanism by which atorvastatin ameliorates cardiac sympathetic nerve sprouting via regulating macrophage polarization. Rat models of MI were created by ligating the left coronary artery. MI-operated rats received either atorvastatin or phosphate-buffered saline for 7days. Immunohistochemical analyses and immunofluorescence staining were used to analyze macrophage infiltration after MI and to detect the distribution and density of growth-associated protein-43 (GAP-43) and tyrosine hydroxylase (TH) in nerve fibers in peri-infarct zones after MI. The polarity of the macrophages that were obtained from the rat peritoneal cavity was examined via flow cytometry. The protein levels of NGF were detected via Western blot analysis, and the concentrations of NGF in the supernatants were determined via enzyme-linked immunosorbent assay. The mRNA levels of NGF, inducible nitric oxide synthase (iNOS), Arginase-1 (Arg1), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were examined by quantitative real-time polymerase chain reaction. The association between VAs and MI was evaluated using programmed electrophysiological stimulation. Macrophages were successfully induced to the M1 (classically activated) and M2 (alternatively activated) phenotypes by stimulation with lipopolysaccharide and interferon-γ (LPS+IFN-γ) and interleukin-4 (IL-4), respectively. Atorvastatin markedly downregulated IL-1β, TNF-α, iNOS, and NGF and upregulated Arg1, shifting the macrophage phenotype from M1 to M2. Moreover, atorvastatin significantly reduced TH levels and the density of GAP-43-positive nerve fibers and decreased inducible VAs. Atorvastatin effectively ameliorated cardiac sympathetic nerve remodeling and prevented VAs after MI by significantly downregulating the expression of NGF, IL-1β, and TNF-α via together with the augmentation of M2 macrophage.

Expression of nerve growth factor in skin tissues and its effect on the proliferation of outer root sheath cells in cashmere goats

Nerve growth factor (NGF) is widely expressed in the nervous system and best understood for its neuronal function. The present study was designed to describe the characteristics of hair follicles and the expression pattern of NGF and its receptor, tyrosine kinase receptor (TrkA), in the skin of Liaoning cashmere goats during hair follicle cycling. Results of hematoxylin and eosin staining revealed that there was a high ratio of secondary to primary follicles, with more active secondary follicles during anagen phase than other phases. The results of quantitative real-time polymerase chain reaction and western blot showed that both NGF and TrkA mRNA and protein levels were persistently detected in the skin tissue during hair follicle cycling. Furthermore, NGF and TrkA mRNA and protein levels during anagen were significantly higher than that during catagen. Using immunohistochemistry, the especially high immunoreactivities of TrkA in the outer root sheath (ORS) and NGF in the internal root sheath (IRS) and ORS were observed during anagen of hair follicles. Meanwhile, NGF and TrkA immunoreactivities were also observed in the epidermis of cashmere goats at similar expression levels as hair follicles. ORS cells were isolated from secondary follicle, and NGF treatment experiments were also studied. Result show that 20ng/mL or 100ng/mL NGF could significantly promote the proliferation of ORS cells in vitro, but the promotion could be blocked by the addition of 20ng/mL K252a, the inhibitor of TrkA. The present study indicates that NGF might be involved in the reconstruction and growth of hair follicles through TrkA tyrosine kinase dependent pathways.

Elevated Nerve Growth Factor/p75NTR Co-localization In Smokers After Eccentric Exercise

PURPOSE: Smoking increases musculoskeletal injury risk and protracts healing. While the underlying mechanisms are poorly understood, altered inflammatory responses may contribute. We previously found at 48h post-eccentric contractions (ECC) that smokers (SM) experienced: 1) 15% greater delayed onset muscle soreness (DOMS) than non-smokers (NS); and 2) altered muscle activity of key pro-inflammatory regulator canonical nuclear factor kappa-beta (p65 NFκB; NS: -7.1±1.3 fold change from baseline; SM: -1.1±1.0 fold). Coinciding with a shift from pro- to anti-inflammatory signaling and peak DOMS, these data suggest delayed inflammatory resolution in SM. Nerve growth factor (NGF) plays a role in pain development and is stimulated by p65 NFκB. We hypothesized that NGF expression and co-localization with both high- (tyrosine receptor kinase A, TrkA) and low- (p75NTR) affinity receptors would be greater in SM than NS following ECC, and may explain greater DOMS in SM. METHODS: Young adult male SM (N=6) and NS (N=5) performed 100 maximal ECC using only the non-dominant knee extensors. Bilateral vastus lateralis biopsies were obtained at 48h post-exercise for NGF mRNA quantification via qPCR. Immunohistochemistry was performed on a subcohort (n=3/group) to quantify and localize NGF, TrkA, and p75NTR protein. RESULTS: ECC did not alter NGF mRNA (NS: 1.9±0.3 fold; SM: 2.8±0.7 fold; p=0.09) or protein levels, which were similarly induced in SM compared to NS (1.1 fold). NGF co-localization with TrkA was unrelated to exercise or smoking status (~23.2±2%). However, SM expressed 2.1 fold higher p75NTR levels than NS (p<0.05). Further, there was a significant interaction (p<0.05) whereby NGF/p75NTR co-localization after ECC decreased in NS (control: 39.6±8.1%; exercise: 31.3±11.4%) but increased in SM (control: 59.2±8.4%; exercise: 72.4±13.7%). CONCLUSIONS: Greater p75NTR expression and p75NTR/NGF co-localization may enhance nerve sensitivity in SM and further augment DOMS. Along with our previous DOMS and inflammatory findings, p75NTR/NGF in SM could delay inflammatory resolution, enhancing risk for chronic pain/disability. This work provides insights into mechanisms that may place SM at greater risk for musculoskeletal injury and impaired healing. Supported, in part, by a grant from the Department of Defense.

Expression of Nerve Growth Factor (NGF) and Its Receptors TrkA and p75 in the Reproductive Organs of Laying Hens

In order to investigate the expression levels of nerve growth factor (NGF) and its receptors (TrkA and p75) in prehierarchical follicles and oviducts of hens, five 130-day-old laying hens were examined by immunohistochemistry and RT-PCR analysis. NGF and its receptors were expressed in theca cells and granulosa cells of prehierarchical follicles, and they were also expressed in the epithelial cells of oviducts. The expression of the genes NGF, TrkA and p75 were significantly different in prehierarchical follicles (p<0.05 or p<0.01), and NGF and TrkA gene expression was significantly different in different parts of oviduct (p<0.05 or p<0.01). The expression of NGF and p75 mRNA levels was highest in large white follicle (LWF), as well as the expression of TrkA in small yellow follicle (SYF). In the oviduct, the expression of NGF was the highest in infundibulum, and lowest in isthmus. These results suggest that NGF may play an important role in the regulation of hen reproduction.

Cartilage stem/progenitor cells are activated in osteoarthritis via interleukin-1β/nerve growth factor signaling.

IntroductionInterleukin-1β (IL-1β) and nerve growth factor (NGF) are key regulators in the pathogenesis of inflammatory arthritis; specifically, IL-1β is involved in tissue degeneration and NGF is involved in joint pain. However, the cellular and molecular interactions between IL-1β and NGF in articular cartilage are not known. Cartilage stem/progenitor cells (CSPCs) have recently been identified in osteoarthritic (OA) cartilage on the basis of their migratory properties. Here we hypothesize that IL-1β/NGF signaling is involved in OA cartilage degeneration by targeting CSPCs.MethodNGF and NGF receptor (NGFR: TrkA and p75NTR) expression in healthy and OA human articular cartilage and isolated chondrocytes was determined by immunostaining, qRT-PCR, flow cytometry and western blot. Articular cartilage derived stem/progenitor cells were collected and identified by stem/progenitor cell characteristics. 3D-cultured CSPC pellets and cartilage explants were treated with NGF and NGF neutralizing antibody, and extracellular matrix changes were examined by sulfated glycosaminoglycan (GAG) release and MMP expression and activity.ResultsExpression of NGF, TrkA and p75NTR was found to be elevated in human OA cartilage. Cellular changes upon IL-1β and/or NGF treatment were then examined. NGF mRNA and NGFR proteins levels were upregulated in cultured chondrocytes exposed to IL-1β. NGF was chemotactic for cells isolated from OA cartilage. Cells isolated on the basis of their chemotactic migration towards NGF demonstrated stem/progenitor cell characteristics, including colony-forming ability, multi-lineage differentiation potential, and stem cell surface markers. The effects of NGF perturbation in cartilage explants and 3D-cultured CSPCs were next analyzed. NGF treatment resulted in extracellular matrix catabolism indicated by increased sGAG release and MMP expression and activity; conversely, treatment with NGF neutralizing antibody inhibited increased MMP levels, and enhanced tissue inhibitor of matrix metalloprotease-1 (TIMP1) expression in OA cartilage explants. NGF blockade with neutralizing antibody also affected cartilage matrix remodeling in 3D-CSPC pellet cultures.ConclusionOur results strongly suggest that NGF signaling is a contributing factor in articular cartilage degeneration in OA, which likely targets a specific subpopulation of progenitor cells, the CSPCs, affecting their migratory and matrix remodeling activities. These findings provide novel cellular/signaling therapeutic targets in osteoarthritic cartilage.Electronic supplementary materialThe online version of this article (doi:10.1186/s13075-015-0840-x) contains supplementary material, which is available to authorized users.

Basic Research on Neurotrophic Factors and Its Application to Medical Uses

The author has studied nerve growth factor (NGF) and its family of neurotrophic factors (neurotrophins) for over 40 years. During the first 20 years, my laboratory established a highly sensitive enzyme immunoassay for NGF and analyzed the regulatory mechanism of NGF synthesis in cultured primary cells. Fibroblast cells cultured from peripheral organs such as the heart and astrocytes from the brain produced a substantial amount of NGF in a growth-dependent manner. Furthermore, synthesis of NGF in these cells could be upregulated by catechol compounds including catecholamines. This observation might explain a physiological relation between the level of NGF mRNA and the density of innervation in the peripheral sympathetic nervous systems. Over the subsequent 20 years, my laboratory investigated the physiological functions of neurotrophic factors, including neurotrophins, during development or post-injury and found that brain-derived neurotrophic factor (BDNF) plays a role in the formation of the laminar structure of the cerebral cortex. In addition, my laboratory discovered that endogenous glial cell line-derived neurotrophic factor (GDNF) contributes to the amelioration of motor activity after spinal cord injury. Therefore we aimed to develop low-molecular weight compounds that generate neurotrophic factor-like intracellular signals to protect or ameliorate neurological/psychiatric diseases. 2-Decenoic acid derivatives and other similar molecules could protect or ameliorate in animal models of mood disorders such as depression and enhance recovery from spinal cord injury-induced motor paralysis. Compounds that can generate neurotrophin-like signals in neurons are expected to be developed as therapeutic drugs for certain neurological or psychiatric disorders.

Expression of nerve growth factor and its receptor, tyrosine kinase receptor A, in rooster testes

Nerve growth factor (NGF), which is required for the survival and differentiation of the nervous system, is also thought to play an important role in the development of mammalian reproductive tissues. To explore the function of NGF in the male reproductive system of non-mammalian animals, we determined the presence of NGF and its receptor, tyrosine kinase receptor A (TrkA), in rooster testes and investigated the regulation of NGF and TrkA expression by follicle-stimulating hormone (FSH). The mRNA and protein levels of NGF and TrkA in 6-week-old rooster testes were lower than those in 12-, 16- or 20-week age groups; levels were highest in the 16-week group. Immunohistochemistry showed that NGF and TrkA were both detected in spermatogonia, spermatocytes and spermatids. NGF immunoreactivity was observed in Leydig cells and strong TrkA signals were present in Sertoli cells. Meanwhile, FSH increased TrkA transcript levels in rooster testes in a dose-dependent manner. We present novel evidence for the developmental and FSH-regulated expression of the NGF/TrkA system, and our findings suggest that the NGF/TrkA system may play a prominent role in chicken spermatogenesis.

Maternal omega-3 fatty acid supplementation to a vitamin B12 deficient diet normalizes angiogenic markers in the pup brain at birth

Vitamin B12 and omega-3 fatty acids are critical for normal brain development and function and their deficiencies during pregnancy could have adverse effects on cognitive performance in children. Our earlier studies indicate that both maternal vitamin B12 and omega-3 fatty acids influence brain development by regulating the levels of neurotrophins. Literature suggests that there exists a cross talk between neurotrophins like nerve growth factor (NGF) and angiogenic factors like vascular endothelial growth factor (VEGF). It remains to be established whether maternal nutrients like vitamin B12 and omega-3 fatty acids influence the levels of angiogenic markers like VEGF and NGF in the brain of the offspring. Therefore the present study examines the effect of maternal vitamin B12 and omega-3 fatty acids on protein and mRNA levels of VEGF, HIF-1 alpha (hypoxia inducible factor alpha) and NGF in the pup brain at birth. Pregnant Wistar rats were divided into five dietary groups (n=8 each): control, vitamin B12 deficient, vitamin B12 deficient+omega-3 fatty acid, vitamin B12 supplemented, vitamin B12 supplemented+omega-3 fatty acid. At birth the pups were dissected to collect the brain tissue. Maternal vitamin B12 deficiency showed lower (p<0.05) pup brain mRNA and protein levels (p<0.01) of VEGF, higher (p<0.01) HIF-1 alpha protein levels, lower (p<0.05) NGF protein levels while NGF mRNA levels were not altered. Omega-3 fatty acid supplementation to a vitamin B12 deficient group normalized the VEGF mRNA levels, NGF protein levels and HIF-1 alpha protein levels. Vitamin B12 supplementation showed similar protein and mRNA levels of VEGF and NGF as well as HIF-1 alpha protein levels as compared to control. Omega-3 fatty acid supplementation to the vitamin B12 supplemented group showed higher (p<0.01) protein and mRNA levels of NGF but the protein and mRNA levels of VEGF were comparable to control. In conclusion maternal vitamin B12 and omega-3 fatty acids both influence the levels and expression of neurotrophins and angiogenic factors in the offspring brain suggesting a possible benefit of combined maternal supplementation of these vital nutrients.

Effect of Bushenwenyanghuayu decoction on nerve growth factor and bradykinin/bradykinin B1 receptor in a endometriosis dysmenorrhea mouse model

ObjectiveTo observe the effects of Bushenwenyanghuayu decoction (BD), a Traditional Chinese Medicine (TCM), on the serum concentration of nerve growth factor (NGF) and bradykinin (BK), and protein and mRNA levels of NGF and bradykinin B1 receptor (BKB1R) in a mouse model of endometriosis dysmenorrhea. MethodsSeventy-five experimental female BALB/c mice were randomly divided into five groups, 15 mice each: sham, model, BD high dose (61.67 g/kg), BD low dose (15.42 g/kg), and gestrinone (0.4 mg/kg) groups. All the mice except for those in the sham group underwent auto-transplantation surgery and were gavaged estradiol valerate (0.5 mg/kg, daily for 12 days) after surgery. On the 12th day, 1 h after administration, writhing response was induced by intraperitoneal injection of oxytocin at 2 U/mouse. The writhing frequency and latency were recorded and the volume of the ectopic foci was measured. The concentration of serum NGF and BK was detected by enzyme-linked immunosorbent assay, the protein expression of NGF and BKB1R was tested by immunohistochemistry and western blotting, and NGF and BKB1R mRNAs were detected by real-time PCR. ResultsCompared with the model group, the volume of the ectopic foci in the treatment groups was significantly lower (P < 0.01), the writhing frequency was decreased (P < 0.05), and the writhing latency was prolonged (P < 0.01). Compared with the sham group, serum NGF and BK levels in the model group were significantly increased (P < 0.01). There were positive correlations for writhing frequency among the NGF and BK groups (P < 0.01). The serum NGF and BK levels were significantly lower in the treatment groups than the model group (P < 0.05). The protein expression of NGF, BKB1R was significantly decreased in the treatment groups compared with the model group (P < 0.01). NGF and BKB1R mRNA expression was significantly decreased in the treatment groups compared with the model group (P < 0.01). ConclusionNGF and BK/BKB1R may play an important role in the development of endometriosis-associated dysmenorrhea, and BD was found to inhibit the development of endometriosis and relieve dysmenorrhea by influencing NGF and BK/BKB1R mRNA and protein levels.

Time Course of Behavioral Alteration and mRNA Levels of Neurotrophic Factor Following Stress Exposure in Mouse.

Stress is known to affect neurotrophic factor expression, which induces depression-like behavior. However, whether there are time-dependent changes in neurotrophic factor mRNA expression following stress remains unclear. In the present study, we tested whether chronic stress exposure induces long-term changes in depression-related behavior, serum corticosterone, and hippocampal proliferation as well as neurotrophic factor family mRNA levels, such as brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3), and ciliary neurotrophic factor (CNTF), in the mouse hippocampus. The mRNA level of neurotrophic factors (BDNF, NGF, NT-3, and CNTF) was measured using the real-time PCR. The serum corticosterone level was evaluated by enzyme-linked immunosorbent assay, and, for each subject, the hippocampal proliferation was examined by 5-bromo-2-deoxyuridine immunostaining. Mice exhibited depression-like behavior in the forced-swim test (FST) and decreased BDNF mRNA and hippocampal proliferation in the middle of the stress exposure. After 15days of stress exposure, we observed increased immobility in the FST, serum corticosterone levels, and BDNF mRNA levels and degenerated hippocampal proliferation, maintained for at least 2weeks. Anhedonia-like behavior in the sucrose preference test and NGF mRNA levels were decreased following 15days of stress. NGF mRNA levels were significantly higher 1week after stress exposure. The current data demonstrate that chronic stress exposure induces prolonged BDNF and NGF mRNA changes and increases corticosterone levels and depression-like behavior in the FST, but does not alter other neurotrophic factors or performance in the sucrose preference test.

Ethanol Extract of Peanut Sprout Exhibits a Potent Anti-Inflammatory Activity in Both an Oxazolone-Induced Contact Dermatitis Mouse Model and Compound 48/80-Treated HaCaT Cells.

BackgroundWe developed an ethanol extract of peanut sprouts (EPS), a peanut sprout-derived natural product, which contains a high level of trans-resveratrol (176.75 µg/ml) and was shown to have potent antioxidant activity.ObjectiveWe evaluated the potential anti-inflammatory activity of EPS by measuring its antioxidant potential in skin.MethodsThe anti-inflammatory activity of EPS was tested using two models of skin inflammation: oxazolone (OX)-induced contact dermatitis in mice and compound 48/80-treated HaCaT cells. As biomarkers of skin inflammation, cyclooxygenase-2 (COX-2) and nerve growth factor (NGF) levels were measured.ResultsOX-induced contact dermatitis was suppressed markedly in mice that were treated with an ointment containing 5% EPS as evidenced by a decrease in the extent of scaling and thickening (p<0.05) and supported by a histological study. COX-2 (messenger RNA [mRNA] and protein) and NGF (mRNA) levels, which were upregulated in the skin of OX-treated mice, were suppressed markedly in the skin of OX+EPS-treated mice. Consistent with this, compound 48/80-induced expression of COX-2 (mRNA and protein) and NGF (mRNA) in HaCaT cells were suppressed by EPS treatment in a dose-dependent manner. As an inhibitor of NF-κB, IκB protein levels were dose-dependently upregulated by EPS. Fluorescence-activated cell sorting (FACS) analysis revealed that EPS scavenged compound 48/80-induced reactive oxygen species (ROS) in HaCaT cells.ConclusionEPS exerts a potent anti-inflammatory activity via its anti-oxidant activity in both mouse skin and compound 48/80-treated HaCaT cells in vitro. Compound 48/80-treated HaCaT cells are a useful new in vitro model of skin inflammation.

Hepatic nerve growth factor induced by iron overload triggers defenestration in liver sinusoidal endothelial cells

The fenestrations of liver sinusoidal endothelial cells (LSECs) play important roles in the exchange of macromolecules, solutes, and fluid between blood and surrounding liver tissues in response to hepatotoxic drugs, toxins, and oxidative stress. As excess iron is a hepatotoxin, LSECs may be affected by excess iron. In this study, we found a novel link between LSEC defenestration and hepatic nerve growth factor (NGF) in iron-overloaded mice. By Western blotting, NGF was highly expressed, whereas VEGF and HGF were not, and hepatic NGF mRNA levels were increased according to digital PCR. Immunohistochemically, NGF staining was localized in hepatocytes, while TrkA, an NGF receptor, was localized in LSECs. Scanning electron microscopy revealed LSEC defenestration in mice overloaded with iron as well as mice treated with recombinant NGF. Treatment with conditioned medium from iron-overloaded primary hepatocytes reduced primary LSEC fenestrations, while treatment with an anti-NGF neutralizing antibody or TrkA inhibitor, K252a, reversed this effect. However, iron-loaded medium itself did not reduce fenestration. In conclusion, iron accumulation induces NGF expression in hepatocytes, which in turn leads to LSEC defenestration via TrkA. This novel link between iron and NGF may aid our understanding of the development of chronic liver disease.