OBJECTIVE: To explore the transcriptional regulation mechanism and biological function of low expression of vasoactive intestinal peptide receptor 1 (VIPR1) in hepatocellular carcinoma (HCC). METHODS: We constructed plasmids carrying wild-type VIPR1 promoter or two mutant VIPR1 promoter sequences for transfection of the HCC cell lines Hep3B and Huh7, and examined the effect of AP-2<i>αi> expression on VIPR1 promoter activity using dual-luciferase reporter assay. Pyrosequencing was performed to detect the changes in VIPR1 promoter methylation level in HCC cells treated with a DNA methyltransferase inhibitor (DAC). Chromatin immunoprecipitation was used to evaluate the binding ability of AP-2<i>αi> to VIPR1 promoter. Western blotting was used to assess the effect of AP-2<i>αi> knockdown on VIPR1 expression and examine the differential expression of VIPR1 in the two cell lines. The effects of VIPR1 overexpression and knockdown on the proliferation, cell cycle and apoptosis of HCC cells were analyzed using CCK8 assay and flow cytometry. We also observed the growth of HCC xenograft with lentivirus-mediated over-expression of VIPR1 in nude mice. RESULTS: Compared with the wild-type VIPR1 promoter group, co-transfection with the vector carrying two promoter mutations and the AP-2<i>αi>-over-expressing plasmid obviously restored the luciferase activity in HCC cells (<i>Pi> < 0.05). DAC treatment of the cells significantly decreased the methylation level of VIPR1 promoter and inhibited the binding of AP-2<i>αi> to VIPR1 promoter (<i>Pi> < 0.01). The HCC cells with AP-2<i>αi> knockdown showed increased VIPR1 expression, which was lower in Huh7 cells than in Hep3B cells. VIPR1 overexpression in HCC cells caused significant cell cycle arrest in G2/M phase (<i>Pi> < 0.01), promoted cell apoptosis (<i>Pi> < 0.001), and inhibited cell proliferation (<i>Pi> < 0.001), while VIPR1 knockdown produced the opposite effects. In the tumor-bearing nude mice, VIPR1 overexpression in the HCC cells significantly suppressed the increase of tumor volume (<i>Pi> < 0.001) and weight (<i>Pi> < 0.05). CONCLUSION VIPR1 promoter methylation in HCC promotes the binding of AP-2<i>αi> and inhibits VIPR1 expression, while VIPR1 overexpression causes cell cycle arrest, promotes cell apoptosis, and inhibits cell proliferation and tumor growth.
Animals ; Carcinoma, Hepatocellular/pathology* ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Gene Expression Regulation, Neoplastic ; Humans ; Liver Neoplasms/pathology* ; Luciferases/genetics* ; Methylation ; Mice ; Mice, Nude ; Receptors, Vasoactive Intestinal Polypeptide, Type I/metabolism* ; Transcription Factor AP-2/metabolism*

BACKGROUND/AIMS: The internal anal sphincter (IAS) plays an important role in maintaining continence and a number of neurotransmitters are known to regulate IAS tone. The aim of this study was to determine the relative importance of the neurotransmitters involved in the relaxant and contractile responses of the porcine IAS. METHODS: Responses of isolated strips of IAS to electrical field stimulation (EFS) were obtained in the absence and presence of inhibitors of neurotransmitter systems. RESULTS: Contractile responses of the sphincter to EFS were unaffected by the muscarinic receptor antagonist, atropine (1 muM), but were almost completely abolished by the adrenergic neuron blocker guanethidine (10 muM). Contractile responses were also reduced (by 45% at 5 Hz, P < 0.01) following desensitisation of purinergic receptors with alpha,beta-methylene-ATP (10 muM). In the presence of guanethidine, atropine, and alpha,beta-methylene-ATP, the remaining relaxatory responses to EFS were examined. These responses were not altered by the cyclooxygenase inhibitor, indomethacin (5 muM), the vasoactive intestinal polypeptide receptor antagonist, [D-p-Cl-Phe6,Leu17]-vasoactive intestinal peptide (PheLeu-VIP; 100 nM), or the purinoceptor antagonists, 8-phenyltheophyline (P1 receptors) or suramin (P2 receptors). However, relaxation responses were reduced by Nomega-nitro-L-arginine (L-NNA; 100 muM), an inhibitor of nitric oxide synthesis (40-50% reduction), zinc protoprophyrin IX (10 muM), an inhibitor of carbon monoxide synthesis (20-40% reduction), and also propargylglycine (30 muM) and aminooxyacetic acid (30 muM), inhibitors of hydrogen sulphide synthesis (15-20% reduction). CONCLUSIONS: Stimulation of IAS efferent nerves releases excitatory and inhibitory neurotransmitters: noradrenaline is the predominant contractile transmitter with a smaller component from ATP, whilst 3 gases mediate relaxation responses to EFS, with the combined contributions being nitric oxide > carbon monoxide > hydrogen sulfide.
Adenosine Triphosphate ; Adrenergic Neurons ; Aminooxyacetic Acid ; Anal Canal* ; Atropine ; Autonomic Pathways ; Carbon Monoxide* ; Carbon* ; Gases ; Guanethidine ; Hydrogen Sulfide* ; Hydrogen* ; Indomethacin ; Neurotransmitter Agents* ; Nitric Oxide* ; Norepinephrine ; Prostaglandin-Endoperoxide Synthases ; Purinergic Antagonists ; Receptors, Muscarinic ; Receptors, Purinergic ; Relaxation* ; Suramin ; Vasoactive Intestinal Peptide ; Zinc

BACKGROUND/AIMS: Previous studies have revealed that mast cells (MCs) may activate the protease-activated receptors and release of neuropeptides involved in the pathogenesis of irritable bowel syndrome (IBS). The levels of protease-activated receptor 2 (PAR-2) and tryptase can contribute to understanding the pathogenesis of IBS. METHODS: Colonoscopic biopsies were performed of 38 subjects (20 with IBS-diarrhea [IBS-D], eight with IBS-constipation [IBS-C], and 10 healthy volunteers). The mRNA and protein levels of tryptase and PAR-2 were assessed by real-time PCR and Western blot. The levels of vasoactive intestinal peptide (VIP), substance P (SP), and calcitonin gene-related peptide (CGRP) were measured by immunohistochemistry, and MCs were counted by toluidine blue staining. RESULTS: Significant increases in the mRNA expression of tryptase (p<0.05, IBS-D, IBS-C vs control) and PAR-2 (p<0.05, IBS-D, IBS-C vs control) and in the tryptase protein level (p<0.05, IBS-D, IBS-C vs control) were detected in IBS. Elevations of MCs, CGRP, VIP and SP (p<0.05, IBS-D vs control) were observed for IBS-D only. CONCLUSIONS: Tryptase levels may upregulate the function of PAR-2, resulting in the release of neuropeptide and they were correlated with clinical symptoms associated with IBS.
Biopsy ; Blotting, Western ; Calcitonin Gene-Related Peptide ; Immunohistochemistry ; Inflammation ; Irritable Bowel Syndrome* ; Mast Cells ; Neuropeptides ; Real-Time Polymerase Chain Reaction ; Receptor, PAR-2* ; Receptors, Proteinase-Activated ; RNA, Messenger ; Substance P ; Tolonium Chloride ; Tryptases* ; Vasoactive Intestinal Peptide

OBJECTIVE: To determine whether chronic alcoholism alters the expression levels of Vasoactive intestinal polypeptide (VIP) and its receptor (VIPR1) in the cochlea of chronic alcoholism rats. METHOD: We measured their expression levels in 30 SD rats, in which we created models of different degrees of chronic alcoholism. We investigated the presence of the mRNA of VIP in the cochlea of chronic alcoholism rats and controls by reverse transcription-polymerase chain reaction (RT-PCR) method. We investigated the presence of proteins of VIPR1 in poisoned rats and controls by western blot. We also evaluated the local distribution of VIP cells by immunohistochemistry. RESULT: We found that the levels of VIP and VIPR1 were downregulated in the chronic alcoholism groups compared to the controls group. The differences in some expression levels were significant different between chronic alcoholism rats and control rats. Moreover, at different degrees of alcohol poisoning in rats, the contents of VIP and VIPR1 differed. Decreased levels of VIP and VIPR1 were detected in the deep chronic alcoholism group compared to the group with low-degree poisoning (P < 0.05). In spiral ganglion cell plasm the expression of VIP and VIPR1 had no significant difference in three groups (P > 0.05). CONCLUSION These results suggest that VIP and VIPR1 play an important role in the auditory function in rats with chronic alcoholism. Chronic alcoholism may cause a peptide hormone secretion imbalance in the auditory system, eventually leading to hearing loss.
Alcoholism ; metabolism ; Animals ; Cochlea ; metabolism ; Disease Models, Animal ; Down-Regulation ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Receptors, Vasoactive Intestinal Polypeptide, Type I ; metabolism ; Spiral Ganglion ; Vasoactive Intestinal Peptide ; metabolism

OBJECTIVETo study the effect of Jiaweisinisan (JWSNS), a traditional Chinese herbal medicinal recipe, on gastric mucosal ultrastructure and brain-gut axis in rat models of chronic psychological stress and elucidate the mechanism of JWSNS for ameliorating stress-induced gastrointestinal dysfunction.

METHODSSixty rats were randomly assigned into normal control group, model group, 3 JWSNS groups (high, moderate, and small doses), and omeprazole group (n=10). Rat models of chronic psychological stress were established by random stressful stimulations, and following the corresponding interventions, plasma adrenocorticotropic hormone (ACTH) and cortisol (CORT) levels were detected using radioimmunoassay, and the mRNA expressions of gastrin receptor in the gastric tissue (GASR) and vasoactive intestinal peptide II receptor (VIPR2) in the jejunal tissue were examined using RT-PCR. Transmission electron microscopy was employed to examine the ultrastructural changes in the gastric mucosa tissue cells of the glandular stomach area and alterations in the intercellular junctions.

RESULTSElectron microscopy revealed obvious damages in gastric mucosal epithelial cell organelles and nuclei in the model rats. These damages were ameliorated after treatments with JWSNS and omeprazole. Compared with the model group, the 3 JWSNS groups and omeprazole group all showed significantly lowered plasma ACTH and CORT levels, increased gastrin receptor mRNA expression and decreased jejunal VIPR2 mRNA expression (P<0.05 or 0.01).

CONCLUSIONJWSNS can obviously ameliorate the pathologies of the gastric mucosa cells, regulate the state of brain-gut axis, and modulate the gastric gastrin receptor and jejunal VIPR2 mRNA expressions in rats with chronic psychological stress.

Adrenal Cortex Hormones ; blood ; Adrenocorticotropic Hormone ; blood ; Animals ; Drugs, Chinese Herbal ; pharmacology ; Gastric Mucosa ; metabolism ; pathology ; ultrastructure ; Hydrocortisone ; blood ; Jejunum ; metabolism ; Male ; Rats ; Rats, Wistar ; Receptors, Bombesin ; metabolism ; Receptors, Vasoactive Intestinal Peptide, Type II ; metabolism ; Stress, Psychological ; pathology

It was hypothesized that the VPAC1 agonist may exert anti-obesity functions because VPAC1 is involved in the anorexigenic effects and the anti-inflammatory function of pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal polypeptide (VIP). Furthermore, our in vitro test showed that the expression of VPAC1 increased significantly after the 3T3-L1 adipocytes were differentiated, and that incubation of adipocytes with VPAC1 agonist (10-1 000 nmol/L per 1x10(6) cells) resulted in stimulation of lipolysis. To test the effect of VPAC1 agonist [Lys15, Arg16, Leu27]-VIP (1-7) GRF (8-27) on diet-induced obesity (DIO), we further designed the following two in vivo experiments: (1) Mice were fed on high-fat diet (HFD) and intraperitoneally (i.p.) treated with VPAC1 agonist simultaneously for 28 d; (2) Mice were given HFD for 35 d, and subsequently fed on the same HFD and i.p. treated with VPAC1 agonist for the next 28 d. The physiological indices, including body weight, weight of white adipose tissue, plasma glucose and blood lipid, were collected. The results showed that treatment with VPAC1 agonist inhibited ingestion significantly and prevented the elevations in body weight and the weights of the white adipose tissues (epididymal and dorsal) induced by HFD. The increases in plasma glucose, cholesterol, triglycerides and LDL induced by HFD were also down-regulated in mice treated with VPAC1 agonist. VPAC1 agonist treatment also improved the glucose tolerance. Therefore, VPAC1 agonist treatment inhibits the development of the obesity induced by HFD and helps to improve the morbidities associated with DIO.
3T3-L1 Cells ; Adipocytes ; drug effects ; Animals ; Body Weight ; Diet, High-Fat ; Mice ; Obesity ; drug therapy ; Receptors, Vasoactive Intestinal Polypeptide, Type I ; agonists ; Vasoactive Intestinal Peptide ; pharmacology

BACKGROUND: The pathogenesis of melasma has not yet been clearly demonstrated. But, clinical manifestations such as remarkable lesional symmetry and the distribution related to trigeminal nerves, suggest that the neural system could play a pathogenic role in melasma. OBJECTIVE: This study was carried out to examine the expression of some neuropeptides and their receptors, which are well known to be major contributors of neuroinflammation in many dermatoses, in melasma lesions. METHODS: Skin biopsies were obtained from the lesional and non-lesional facial skin of 6 Korean women with melasma. Immunofluorecence staining and confocal laser scanning microscopy were performed. RESULTS: In our results, no difference could be detected with regard to the intensity of immunoreactivity for vasoactive intestinal peptide (VIP), calcitonin gene-related peptide (CGRP), calcitonin gene-related peptide receptor (CGRPR), substance P (SP), substance P receptor (SPR), somatostatin (SOM), pituitary adenylate cyclase activating peptide (PACAP) and pituitary adenylate cyclase activating peptide receptor (PACAPR) in the lesional skins compared with the non-lesional skins. CONCLUSION: These results suggest that neuroinflammation induced by neuropeptides such as substance P, calcitonin gene-related peptide, vasoactive intestinal peptide, and somatostatin and their receptors included in this study, are not directly associated with melasma pathogenesis.
Adenylyl Cyclases ; Biopsy ; Calcitonin Gene-Related Peptide ; Female ; Humans ; Melanosis ; Microscopy, Confocal ; Neuropeptides ; Receptors, Neurokinin-1 ; Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide ; Skin ; Skin Diseases ; Somatostatin ; Substance P ; Trigeminal Nerve ; Vasoactive Intestinal Peptide

OBJECTIVE: To investigate the effect of regulation of VIPhybrid, an unselective antagonist of vasoactive intestinal peptide receptors (VIPR), on the formation and development of form deprivation myopia (FDM) in chick and the expression of protein and mRNA of VIP on the retina and choroids of in chicks. METHODS: Seventy-two 1-day-old yellow healthy leghorn chicks were assigned into 6 groups (12 in each group). Eyes in Group I were covered on the right as a blank control group. Eyes in GroupII were those eyes having been injected with 20 microL saline into vitreous cavity and then covered as a negative control group. Eyes in GroupIII,IV and V were injected with 20 microL VIPhybrid with low (3*10(-12) mol/L), middle (3*10(-10) mol/L) and high (3*10(-8) mol/L) dosage into vitreous cavity and then covered as experimental groups. The above groups had been continuously covered for 1 week. Eyes in Group VI were uncovered and uninjected as a normal control group. Diopter was detected using retinoscopic refraction. The eyeball axis was determined using ophthalmological ultra-A. The expression of protein and mRNA of VIP on retina-choroids-sclera were investigated by SP immunohistochemistry staining and RT-PCR. RESULTS: Form deprivation for 1 week induced high myopia eyes and elongated eyeball axis in GroupI and GroupII, and there was no difference between the 2 groups (P>0.05). The diopter and eyeball axis were significantly reduced in Group III, IV, and V as compared with Group I and II (P<0.01), but the diopter was higher and the eyeball axis was longer than those of Group VI. The diopter and eyeball axis had negative correlation with the concentration gradient of VIPhybrid. The expressions of protein and mRNA of VIP in Group III, IV, and V were down-regulated as compared with those of Group I and I I(P<0.01)and also down-regulated with the increase of concentration of VIPhybrid. CONCLUSION VIPhybrid can decrease the development of FDM in chicks, which may provide a new pathway for drug therapy of myopia in human beings.
Animals ; Animals, Newborn ; Chickens ; Myopia ; etiology ; metabolism ; RNA, Messenger ; biosynthesis ; genetics ; Receptors, Vasoactive Intestinal Peptide ; antagonists & inhibitors ; Recombinant Fusion Proteins ; pharmacology ; Retina ; metabolism ; Vasoactive Intestinal Peptide ; biosynthesis ; genetics

BACKGROUND/AIMS: Interactions between H. pylori and gastric epithelial cells contribute to gastric inflammation and epithelial damage. This study was performed to evaluate the gene expression profile of AGS cells by adhesion of H. pylori. METHODS: Changes in AGS cell gene expression induced by co-culturing with H. pylori (G69a strain) (4, 12, 24, 48 hours) were monitored using oligonucleotide microarray. Real-time reverse transcription-polymerase chain reaction (RT-PCR) was performed for data validation by the Assay-on-Demand Gene Expression product method. RESULTS: A total of 270 (2.66%) and 19 genes (0.19%) were up-regulated in AGS cells by H. pylori adhesion. Gene ontology analysis showed that up-regulated genes were categorized into endolipidase activity (17 genes), receptor binding (17 genes), integrin binding (4 genes), and two down-regulated genes into GTP binding category. The expression levels of 20 up- and 5 down-regulated genes were quantified by real-time RT-PCR. Sixteen genes involving cytokine activity (IL8, IL1B, TNF), hydrolase activity (PTP4A1, ERCC1, CASP8, CASP7, ACIN1), VIP receptor activity (VIPR2), and neuropeptide Y receptor activity (GPR83) were confirmed to be up-regulated. Five genes, namely, ARF3, M17S2, DDB2, AWP1, and WTAP were confirmed to be down-regulated. CONCLUSIONS: Host genes are significantly changed by H. pylori adhesion, which might explain the gastroduodenal pathogenesis induced by H. pylori infection.
Epithelial Cells ; Gene Expression* ; Gene Ontology ; Guanosine Triphosphate ; Helicobacter pylori* ; Helicobacter* ; Inflammation ; Oligonucleotide Array Sequence Analysis ; Receptors, Neuropeptide Y ; Receptors, Vasoactive Intestinal Peptide ; Transcriptome*

The present study was aimed to investigate the changes of vasoactive intestinal polypeptide (VIP) and VIP receptor 1 (VIPR1) in small intestinal and hepatic tissues during macaque development. The tissue samples of small intestine, liver and blood samples from peripheral and portal vein of 4 macaques of 6-month fetus, 2-day neonate, 45-day neonate and adult were obtained after anesthetization. The concentration of VIP in blood or tissues of macaques was measured by radioimmunoassay. The distribution of VIP in small intestinal or hepatic tissues was visualized by immunohistochemical staining. The expression of VIPR1 was detected by in situ hybridization. The results showed that: (1) VIP concentration in intestinal tissue of 6-month fetus was (20.7+/-14.3) ng/mg protein, and a few VIP-positive nerve fibers first appeared in intestinal villus root and submucosal layer but not in muscle layer. The intestinal concentration of VIP increased gradually with macaque development and reached (514.8+/- 49.2) ng/mg protein in adult, significantly higher than that in 6-month fetus (P<0.01). (2) In adult animal, VIP-positive nerve fibers became thicker and gradually extended into the mucosal crypt, submucosal layer nerve, myenteric nerve plexus of annular muscle and indulge muscle, and annular muscle. Correspondingly, the expression of VIPR1 in intestine was up-regulated during development. (3) On the contrary, the levels of VIP and VIPR1 in liver were gradually decreased during development. (4) VIP concentration in small intestinal tissue was higher than that in hepatic tissue during development. The VIP level in portal vein was also significantly higher than that in peripheral blood during development. In conclusion, the levels of VIP and VIPR1 in mucosal crypt, submucosal layer nerve, myenteric nerve plexus of annular muscle and indulge muscle increase rapidly after birth. Most of VIP from intestinal tract is degraded in portal vein before entering liver, suggesting that VIP does not metabolize and decompose in liver, and that VIPR1 is only present in embryo hepatic blood vessels.
Animals ; Animals, Newborn ; Fetus ; Intestine, Small ; metabolism ; Liver ; metabolism ; Macaca mulatta ; embryology ; growth & development ; metabolism ; Receptors, Vasoactive Intestinal Polypeptide, Type I ; metabolism ; Vasoactive Intestinal Peptide ; metabolism