The extracellular domain (p75ECD) of p75 neurotrophin receptor (p75NTR) antagonizes Aβ neurotoxicity and promotes Aβ clearance in Alzheimer's disease (AD). The impaired shedding of p75ECD is a key pathological process in AD, but its regulatory mechanism is largely unknown. This study was designed to investigate the presence and alterations of naturally-occurring autoantibodies against p75ECD (p75ECD-NAbs) in AD patients and their effects on AD pathology. We found that the cerebrospinal fluid (CSF) level of p75ECD-NAbs was increased in AD, and negatively associated with the CSF levels of p75ECD. Transgenic AD mice actively immunized with p75ECD showed a lower level of p75ECD and more severe AD pathology in the brain, as well as worse cognitive functions than the control groups, which were immunized with Re-p75ECD (the reverse sequence of p75ECD) and phosphate-buffered saline, respectively. These findings demonstrate the impact of p75ECD-NAbs on p75NTR/p75ECD imbalance, providing a novel insight into the role of autoimmunity and p75NTR in AD.
Mice ; Animals ; Alzheimer Disease/pathology* ; Receptor, Nerve Growth Factor ; Amyloid beta-Peptides ; Autoantibodies ; Mice, Transgenic

This study aims to explore the effect of Jinzhen Oral Liquid(JOL) on cough after infection in rats and the mechanism. To be specific, a total of 60 male SD rats were classified into 6 groups: normal group(equivalent volume of distilled water, ig), model group(equivalent volume of distilled water, ig), Dextromethorphan Hydrobromide Oral Solution group(3.67 mL·kg~(-1), ig), high-, medium-, and low-dose JOL groups(11.34, 5.67, and 2.84 mL·kg~(-1), respectively, ig). Lipopolysaccharide(LPS, nasal drip), smoking, and capsaicin(nebulization) were employed to induce cough after infection in rats except the normal group. Administration began on the 19 th day and lasted 7 days. Capsaicin(nebulization) was used to stimulate cough 1 h after the last administration and the cough frequency and cough incubation period in rats were recorded. The pathological morphology of lung tissue was observed based on hematoxylin-eosin(HE) staining. Immunohistochemistry(IHC) was used to detect the specific expression of transient receptor potential vanilloid 1(Trpv1), nerve growth factor(NGF), tropomyosin receptor kinase A(TrkA), and phosphorylated-p38 mitogen-activated protein kinase(p-p38 MAPK) in lung tissue, Western blot the protein expression of Trpv1, NGF, TrkA, and p-p38 MAPK in lung tissue, and real-time fluorescent quantitative polymerase chain reaction(real-time PCR) the mRNA expression of Trpv1, NGF, and TrkA. The results showed that model group demonstrated significantly high cough frequency, obvious proliferation and inflammatory cell infiltration in lung tissue, significantly enhanced positive protein expression of Trpv1, NGF, TrkA, and p-p38 MAPK in lung tissue and significant increase in the mRNA expression of Trpv1, NGF, and TrkA compared with the normal group. Compared with the model group, JOL can significantly reduce the cough frequency, alleviate the pathological changes of lung tissue, and decrease the protein expression of Trpv1, NGF, TrkA, and p-p38 MAPK in lung tissue, and high-dose and medium-dose JOL can significantly lower the mRNA expression of Trpv1, NGF, and TrkA. This study revealed that JOL can effectively inhibit Trpv1 pathway-related proteins and improve cough after infection. The mechanism is that it reduces the expression of NGF, TrkA, and p-p38 MAPK in lung tissue, thereby decreasing the expression of Trpv1 and cough sensitivity.
Animals ; Capsaicin/adverse effects* ; Cough/drug therapy* ; Dextromethorphan/adverse effects* ; Eosine Yellowish-(YS)/adverse effects* ; Hematoxylin ; Lipopolysaccharides/adverse effects* ; Male ; Medicine, Chinese Traditional ; Nerve Growth Factor/metabolism* ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Receptor, trkA/metabolism* ; TRPV Cation Channels/metabolism* ; Tropomyosin/metabolism* ; Water/metabolism* ; p38 Mitogen-Activated Protein Kinases/metabolism*

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Zusanli" (ST 36) on duodenal mast cells, nerve growth factor (NGF) and neurotrophic tyrosine kinase receptor type 1 (NTRK1), and to explore the mechanism of electroacupuncture at Zusanli (ST 36) on functional dyspepsia (FD). METHODS: Sixty SPF-grade 10-day-old SD rats were randomly divided into a normal group, a model group, a ketotifen group and an EA group, 15 rats in each group. The FD model was prepared by iodoacetamide combined with rat tail clamping method in the model group, the ketotifen group and the EA group. The rats in the ketotifen group were injected intraperitoneally with ketotifen (1 mg•kg^-1•d^-1) for 7 days; the rats in the EA group were treated with EA at bilateral "Zusanli" (ST 36), with disperse-dense wave, frequency of 2 Hz/50 Hz and intensity of 0.5 mA, 20 min each time, once a day for 14 days. The gastric emptying rate and small intestinal propulsion rate in each group were observed; the morphology of duodenal mucosa was observed by HE staining; the toluidine blue staining was used to observe the number and degranulation of mast cells in duodenal mucosa; the protein and mRNA expressions of NGF, NTRK1 in duodenum were detected by Western blot and real-time PCR; the level of interleukin-1β (IL-1β) in duodenum was measured by ELISA. RESULTS: Compared with the normal group, the gastric emptying rate and small intestinal propulsion rate in the model group were decreased (P<0.01); compared with the model group, the gastric emptying rate and small intestinal propulsion rate in the ketotifen group and the EA group were increased (P<0.01); the small intestinal propulsion rate in the EA group was higher than that in the ketotifen group (P<0.01). In the model group, local defects in duodenal mucosa were observed with a small amount of inflammatory cell infiltration; no obvious abnormality was found in duodenal mucosa of the other groups. Compared with the normal group, the mast cells of duodenal mucosa in the model group were increased significantly with significant degranulation; compared with the model group, the mast cells of duodenal mucosa in the ketotifen group and the EA group were decreased significantly, and the degranulation was not obvious. Compared with the normal group, the protein and mRNA expressions of NGF, NTRK1 as well as the level of IL-1β in duodenum in the model group were increased (P<0.01); compared with the model group, the protein and mRNA expressions of NGF, NTRK1 as well as the levels of IL-1β in duodenum in the ketotifen group and the EA group were decreased (P<0.01, P<0.05); compared with the ketotifen group, the mRNA expression of NGF, as well as the protein and mRNA expressions of NTRK1 in duodenum in the EA group were decreased (P<0.05, P<0.01). CONCLUSION EA at "Zusanli" (ST 36) could inhibit the activation of duodenal mast cells and regulate the expressions of NGF and its receptor to improve the low-grade inflammatory response of duodenum, resulting in treatment effect on FD.
Acupuncture Points ; Animals ; Duodenum/metabolism* ; Dyspepsia/therapy* ; Electroacupuncture ; Ketotifen ; Mast Cells/metabolism* ; Nerve Growth Factor/metabolism* ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Receptor, trkA/genetics*

The neurotrophin receptor kinase (NTRK) gene encodes neurotrophic factor receptor tyrosine kinase (NTRK), which plays an important role in the development and function of the nervous system. NTRK gene fusion mutation results in the production of chimeric NTRK proteins, which have carcinogenic potential through constitutive activation or overexpression. NTRK gene fusion mutation can lead to a special type of wild type gastrointestinal stromal tumor (GIST), whose clinical manifestations and treatment are completely different from other types of GIST. This fusion mutation can be detected clinically by a variety of methods, including tumor DNA and RNA sequencing and immunohistochemical staining. In patients with NTRK fusion positive tumors, NTRK inhibitors such as larotrectinib and entrectinib have shown good antitumor efficacy, with clinical response rates as high as 75%. Therefore, there is a need to improve the recognition and detection of fuch patients and to improve their prognosis by individualized and precise treatment with TRK inhibitors.
Gastrointestinal Stromal Tumors/genetics* ; Gene Fusion ; Humans ; Neoplasms ; Nerve Growth Factors ; Protein Kinase Inhibitors ; Receptor, trkA/genetics* ; Receptors, Nerve Growth Factor/genetics*

OBJECTIVE: Nerve growth factor (NGF) is a member of the neurotrophic factor family and plays a vital role in the physiological processes of organisms, especially in the nervous system. Many recent studies have reported that NGF is also involved in the regulation of tumourigenesis by either promoting or suppressing tumor growth, which depends on the location and type of tumor. However, little is known regarding the effect of NGF on interspinal schwannoma (IS). In the present study, we aimed to explored whether mouse nerve growth factor (mNGF), which is widely used in the clinic, can influence the growth of interspinal schwannoma cells (ISCs) isolated from IS in vitro.METHODS: ISCs were isolated, cultured and identified by S-100 with immunofluorescence analysis. S-100-positive cells were divided into five groups, and separately cultured with various concentrations of mNGF (0 [phosphate buffered saline, PBS], 40, 80, 160, and 320 ng/mL) for 24 hours. Western blot and quantantive real time polymerase chain reaction (PCR) were applied to detect tyrosine kinase A (TrkA) receptor and p75 neurotrophin receptor (p75(NTR)) in each group. Crystal violet staining was selected to assess the effect of mNGF (160 ng/mL) on ISCs growth.RESULTS: ISCs growth was enhanced by mNGF in a dose-dependent manner. The result of crystal violet staining revealed that it was significantly strengthened the cells growth kinetics when cultured with 160 ng/mL mNGF compared to PBS group. Western blot and quantantive real time PCR discovered that TrkA receptor and mRNA expression were both up-regualated under the condition of mNGF, expecially in 160 ng/mL, while the exoression of p75(NTR) demonstrated no difference among groups.CONCLUSION: From these data, we conclude that exogenous mNGF can facilitate ISC growth by activating both TrkA receptor and p75(NTR). In addition, patients who are suffering from IS should not be administered mNGF in the clinic.
Animals ; Blotting, Western ; Fluorescent Antibody Technique ; Gentian Violet ; Humans ; In Vitro Techniques ; Kinetics ; Mice ; Nerve Growth Factor ; Nervous System ; Neurilemmoma ; Physiological Processes ; Protein-Tyrosine Kinases ; Real-Time Polymerase Chain Reaction ; Receptor, Nerve Growth Factor ; Receptor, trkA ; Receptors, Nerve Growth Factor ; RNA, Messenger

OBJECTIVE: Notch receptors are heterodimeric transmembrane proteins that regulate cell fate, such as differentiation, proliferation, and apoptosis. Dysregulated Notch pathway signaling has been observed in glioblastomas, as well as in other human malignancies. Nerve growth factor (NGF) is essential for cell growth and differentiation in the nervous system. Recent reports suggest that NGF stimulates glioblastoma proliferation. However, the relationship between NGF and Notch1 in glioblastomas remains unknown. Therefore, we investigated expression of Notch1 in a glioblastoma cell line (U87-MG), and examined the relationship between NGF and Notch1 signaling.METHODS: We evaluated expression of Notch1 in human glioblastomas and normal brain tissues by immunohistochemical staining. The effect of NGF on glioblastoma cell line (U87-MG) was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. To evaluate the relationship between NGF and Notch1 signaling, Notch1 and Hes1 expression were evaluated by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis, respectively. To confirm the effects of NGF on Notch1 signaling, Notch1 and Hes1 small interfering RNAs (siRNAs) were used.RESULTS: In immunohistochemistry, Notch1 expression was higher in glioblastoma than in normal brain tissue. MTT assay showed that NGF stimulates U87-MG cells in a dose-dependent manner. RT-PCR and Western blot analysis demonstrated that Notch1 and Hes1 expression were increased by NGF in a dose-dependent manner. After transfection with Notch1 and Hes1 siRNAs, there was no significant difference between controls and 100 nM NGF-β, which means that U87-MG cell proliferation was suppressed by Notch1 and Hes1 siRNAs.CONCLUSION: These results indicate that NGF stimulates glioblastoma cell proliferation via Notch1 signaling through Hes 1.
Apoptosis ; Blotting, Western ; Brain ; Cell Line ; Cell Proliferation ; Glioblastoma ; Humans ; Immunohistochemistry ; Nerve Growth Factor ; Nervous System ; Polymerase Chain Reaction ; Receptor, Notch1 ; Receptors, Notch ; Reverse Transcription ; RNA, Small Interfering ; Transfection

Kallmann syndrome (KS) is a rare pediatric disease with major manifestations of olfactory dysfunction and hypogonadotropic hypogonadism. Five children (4 boys and 1 girl) with KS reported in this article were aged between 6 months and 19 years at the time when they attended the hospital. All the children had the clinical manifestation of hypogonadotropic hypogonadism; in addition, three children had olfactory dysfunction (two were found to have olfactory bulb dysplasia on magnetic resonance imaging), one had cleft lip and palate, and one had micropenis and cryptorchidism with right renal agenesis during infancy. All the five children had normal karyotype and their parents had normal clinical phenotypes. The uncle of one child had underdeveloped secondary sexual characteristics and olfactory disorder since childhood. High-throughput sequencing found two known heterozygous missense mutations in the FGFR1 gene, i.e., c.1097C>T(p.P366L) and c.809G>C(p.G270A), in two children. One child had a novel frameshift mutation, c.1877_1887/p.S627Tfs*6, in the KAL1 gene; this deletion mutation caused a frameshift in base sequence and produced truncated proteins, which led to a significant change in protein structure, and thus it was highly pathogenic. It is concluded that KS has great clinical and genetic heterogeneity and can be accompanied by incomplete dominant inheritance and that gene detection helps with the diagnosis of this disease.
Adolescent ; Child ; Child, Preschool ; DNA Mutational Analysis ; Extracellular Matrix Proteins ; Female ; Heterozygote ; Humans ; Hypogonadism ; Infant ; Kallmann Syndrome ; Male ; Mutation ; Nerve Tissue Proteins ; Receptor, Fibroblast Growth Factor, Type 1 ; Young Adult

Sympathetic arborizations act as the essential efferent signals in regulating the metabolism of peripheral organs including white adipose tissues (WAT). However, whether these local neural structures would be of plastic nature, and how such plasticity might participate in specific metabolic events of WAT, remains largely uncharacterized. In this study, we exploit the new volume fluorescence-imaging technique to observe the significant, and also reversible, plasticity of intra-adipose sympathetic arborizations in mouse inguinal WAT in response to cold challenge. We demonstrate that this sympathetic plasticity depends on the cold-elicited signal of nerve growth factor (NGF) and TrkA receptor. Blockage of NGF or TrkA signaling suppresses intra-adipose sympathetic plasticity, and moreover, the cold-induced beiging process of WAT. Furthermore, we show that NGF expression in WAT depends on the catecholamine signal in cold challenge. We therefore reveal the key physiological relevance, together with the regulatory mechanism, of intra-adipose sympathetic plasticity in the WAT metabolism.
Adipose Tissue, Beige ; cytology ; diagnostic imaging ; innervation ; metabolism ; Animals ; Catecholamines ; metabolism ; Cold Temperature ; Imaging, Three-Dimensional ; Mice ; Nerve Growth Factor ; metabolism ; Neuronal Plasticity ; Receptor, trkA ; metabolism ; Signal Transduction ; Sympathetic Nervous System ; physiology

Enhancing adult nerve regeneration is a potential therapeutic strategy for treating spinal cord injury. Vascular endothelial growth factor (VEGF) is a major contributor to angiogenesis, which can reduce the spinal cord injury by inhibiting the inflammation and improve recovery after spinal cord injury. We have previously demonstrated that exogenous VEGF has neurotrophic effects on injured spinal nerves in organotypic spinal cord slice cultures. However, the mechanisms underlying the neurite growth by exogenous VEGF remain to be explored in spinal cord. In this study, we found out that exogenous VEGF mediated axonal outgrowth through VEGF receptor 1 (VEGFR1) and VEGFR2, both of which were expressed on organotypic spinal cord slices. Although VEGFR1 and VEGFR2 were constitutively expressed in some cells of control spinal cord slices, VEGF treatment upregulated expression of VEGFR1 and VEGFR2. Both VEGFR1 and VEGFR2 were expressed in neuronal cells as well as glial cells of organotypic spinal cord slices. We also observed that VEGF-induced axonal outgrowth was attenuated by a specific mitogen-activated protein kinase (MAPK) inhibitor PD98059 and a specific phosphoinositide 3-kinase (PI3K) inhibitor wortmannin. Thus, these findings suggest that these MAPK and PI3K pathways have important roles in regulating VEGF-induced axonal outgrowth in the postnatal spinal cord.
Adult ; Axons* ; Humans ; Inflammation ; Nerve Regeneration ; Neurites ; Neuroglia ; Neurons ; Protein Kinases ; Receptors, Vascular Endothelial Growth Factor* ; Spinal Cord Injuries ; Spinal Cord* ; Spinal Nerves ; Vascular Endothelial Growth Factor A* ; Vascular Endothelial Growth Factor Receptor-1*

OBJECTIVETo investigate the expressions and action mechanisms of nerve growth factor (NGF) receptors TrkA and p75NTR in the oncogenesis and progression of prostate cancer (PCa).

METHODSUsing immunohistochemistry, we detected the expressions of TrkA and p75NTR in 62 PCa and 35 benign prostatic hyperplasia (BPH) samples, and conducted statistical analysis on the basis of clinical data.

RESULTSIndependent-samples t-test showed that, along with poorer tissue differentiation or higher clinical stage of PCa, the expression of TrkA was significantly up-regulated, that of p75NTR remarkably down-regulated, and the expression ratio of TrkA to p75NTR markedly increased. The TrkA/p75NTR ratio was 0.32 in the BPH, 0.52 in the PCa tissue with Gleason score of 6, 1.65 in the PCa tissue with Gleason score of 7, 5.75 in the PCa tissue with Gleason score ≥ 8, 0.89 in the clinical stage of pT2, 1.5 in pT3 a, 3.75 in pT3b, and 7.00 in pTxN1.

CONCLUSIONThe abnormally increased expression ratio of TrkA to p75NTR might be one of the essential features of malignant transformation of prostate cells. A higher TrkA/p75NTR expression ratio may be associated with a lower tissue differentiation, a higher clinical stage or Gleason score, and therefore a poorer prognosis.

Humans ; Immunohistochemistry ; Male ; Neoplasm Grading ; Neoplasm Staging ; Nerve Tissue Proteins ; metabolism ; Prognosis ; Prostatic Hyperplasia ; pathology ; Prostatic Neoplasms ; pathology ; Receptor, trkA ; metabolism ; Receptors, Nerve Growth Factor ; metabolism ; Up-Regulation