Vasoactive Intestinal Peptide Gene Research Articles

Vasoactive Intestinal Peptide (VIP) and its Receptors in Adipose Tissue: Implications for Cold Stress Adaptation.

Adipose tissue represents an organ that is highly dynamic and contributes toward vital survival events such as immune responses, lactation, metabolism fuel, and thermogenesis. Data emerging from recent studies support the notion of adipose tissue being organized into a complex system characterized by a discrete anatomy, elevated physiological plasticity, and specific vascular and nerve supplies. Vasoactive intestinal peptide (VIP), along with its receptors, type 1 (VPAC1) and type 2 (VPAC2), has been implicated in various physiological and pathophysiological processes. However, studies on VIP and its receptors in adipose tissue are limited. To explore VIP's presence and activity, as well as its adipose tissue-based receptors, we conducted a study on isolated adipocytes and adipose tissue from inguinal white adipose tissue (WAT) and interscapular brown adipose tissue (BAT) in normal and cold-stressed rats. Our findings indicate the presence of the gene expression VIP and VPAC1 in both WAT and BAT under normal conditions, while VPAC2 was absent. In both WAT and BAT, cold exposure upregulated VIP gene expression. However, the response of VIP receptors to cold exposure is controversial. VPAC2 gene expression was induced in both WAT and BAT, while VPAC1 gene expression presented no change of significance in BAT and a slight reduction in WAT. Additionally, VIP, VPAC1, and VPAC2 proteins were identified from Western blot studies on white and brown adipocytes. After exposure to cold there was an increase of significance in the VIP, VPAC1, and VPAC2 protein levels. This study provides novel insights into how VIP and its receptors alter gene expression and protein levels in adipose tissue and adipocytes during cold stress, indicating their potential involvement in adipose tissue regulation. The findings propose VIP's potentially crucial role in adipose tissue's adaptation to cold stress by affecting the metabolic and biochemical functions of subcutaneous and interscapular adipocytes, with potentially significant implications in the context of developing therapies targeting metabolic disorders.

Vasoactive Intestinal Polypeptide in the Enteric Neural Plexus Promotes Microbiome Diversity and Resistance to GvHD

Abstract Graft-versus-host disease (GvHD) in allo-transplant recipients is characterized by donor T cell- mediated damage to recipient organs and changes in the gut microbiome. Vasoactive intestinal peptide (VIP), an immunosuppressive neuropeptide, directs T cell responses towards a Th2 phenotype while inhibiting proinflammatory cytokine production. VIP-producing enteric neurons contribute to the mucosal barrier and maintain gut microbiome homeostasis. The impact of VIP production by host cells on GvHD remains unclear. We examined the effect of endogenous VIP synthesis in modulating GvHD in multiple murine allo-BMT models. VIP knock-out mice were exquisitely sensitive to GvHD, experiencing activation and expansion of Th1- and Th17-polarized T cells and early death. Transplanting radiation chimeric mice in which the VIP gene was knocked out in either hematopoietic or non-hematopoietic cells demonstrated that VIP production by non-hematopoietic tissues limited the GvHD activity of donor T cells. Immunofluorescence staining demonstrated VIP expression in enteric neurons in allo-BMT recipients, consistent with local effects of VIP on T cells and the gut microbiome. VIP- KO mice had lower gut pH, higher frequencies of Bacillota species, and less microbiome diversity post-transplantation. These data support the crucial role of VIP in maintaining the diversity of the gut microbiome with beneficial commensal species and in modulating the alloreactivity of donor T cells after allo-BMT.

MiR-30c affects the pathogenesis of ulcerative colitis by regulating target gene VIP

MicroRNAs play a crucial role in regulating the epithelial barrier and immune response, which are implicated in the pathogenesis of ulcerative colitis (UC). This study aimed to investigate the role and molecular mechanism of miR-30c in the pathogenesis of UC using a dextran sulfate sodium salt (DSS)-induced colitis model, which is similar to ulcerative colitis. Wild-type (WT) and miR-30c knockout (KO) mice were assigned to either control or DSS-treated groups to evaluate the influence of aberrant miR-30c expression on UC pathogenesis. The disease activity index, inflammatory factors, and the extent of pathological and histological damage in colon tissues were analyzed. The effect of miR-30c on vasoactive intestinal peptide (VIP) gene expression was validated through luciferase reporter assay, qRT-PCR, Western blotting, and immunohistochemistry. The results showed that miR-30c KO mice with DSS-induced colitis model showed more severe phenotypes: significantly higher disease activity indices, significant body weight loss, reduced length of the colon of mice, increased number of aberrant crypt structures, reduced mucus secretion, and significant differences in inflammatory factors. These findings suggested that the absence of miR-30c might promote DSS-induced colitis, and the targe-regulatory effect of miR-30c on VIP might play an important role in the development of colitis.

Effects of gonadotropin-inhibitory hormone on testicular development and reproduction-related gene expression in roosters

Gonadotropin-inhibitory hormone (GnIH) plays a crucial role in regulating reproduction in the hypothalamus of poultry and has been intensely investigated since its discovery. This study aimed to assess the effects of GnIH on testicular development, as well as on reproduction-related hormone release and gene expression levels in roosters. The administration of exogenous GnIH resulted in a significant reduction in testis weight, testis volume and semen quality (p < 0.05). Additionally, exogenous GnIH significantly up-regulates the expression of GnIH, and down-regulates the expression of PRL (p < 0.05). GnIH application also decreased the GnRH, vasoactive intestinal peptide (VIP) and luteinizing hormone β subunit(LHβ)gene expression levels. Meanwhile, by neutralizing the effects of endogenous GnIH through immunization, testicular development on day 150 in roosters was significantly promoted. Compared to the control condition, GnIH immunization significantly down-regulated the expression of the VIP and PRL genes (p < 0.05). In conclusion, we found that exogenous GnIH treatment inhibited testicular development, reduces PRL gene expression, and suppressed reproductive performance in roosters. Conversely, GnIH immunization down-regulated VIP and PRL genes, activates the reproductive system, and promotes the reproductive activity and testicular development of roosters.

Evaluation of serum VIP and aCGRP during pulmonary exacerbation in cystic fibrosis: A longitudinal pilot study of patients undergoing antibiotic therapy.

Objective monitoring of improvement during treatment of pulmonary exacerbation can be difficulty in children when pulmonary function testing cannot be obtained. Thus, the identification of predictive biomarkers to determine the efficacy of drug treatments is of high priority. The major aim of the current study was to investigate the serum levels of vasoactive intestinal peptide (VIP) and alpha calcitonin gene related peptide (aCGRP) of cystic fibrosis pediatric patients during pulmonary exacerbation and post-antibiotic therapy, and possible associations of their levels with different clinicopathological parameters. 21 patients with cystic fibrosis were recruited at onset of pulmonary exacerbation. Serum was collected at time of admission, three days post-antibiotic therapy, and two weeks post-antibiotic therapy (end of antibiotic therapy). Serum VIP and aCGRP levels were measured using ELISA. Overall least square means of serum aCGRP level but not VIP changed from time of exacerbation to completion of antibiotic therapy (p = 0.005). Serum VIP was significantly associated with the presence of diabetes mellitus (p = 0.026) and other comorbidities (p = 0.013), and with type of antibiotic therapy (p = 0.019). Serum aCGRP level was significantly associated with type of antibiotic therapy (p = 0.012) and positive Staphylococcus aureus microbiology test (p = 0.046). This study could only show significant changes in serum aCGRP levels following treatment of pulmonary exacerbations. Future studies with larger sample size are required to investigate the clinical importance of VIP and aCGRP in cystic fibrosis patients.

Association of polymorphisms of vasoactive intestinal peptide and its receptor with reproductive traits of turkey hens

The aim of this study was to identify variations of vasoactive intestinal peptide (VIP) and VIP receptor-1 (VIPR-1) genes that might be associated with turkey reproductive traits. One hundred twenty turkey hens were recorded for age at first egg (AFE), first egg weight (FEW), egg number (EN), total egg weight (TEW), laying period (LP), and broodiness. The DNA was isolated from blood samples and subjected to PCR amplification of the meleagrine VIP and VIPR-1 genes. The SNPs were detected by single-strand conformation polymorphism and the variant DNA fragments were sequenced. One mutation in 3’-UTR of VIP (G5846A) and two SNPs in intron 2 of VIPR-1 (C17687T and A17690T) were found, all of them novel. The associations of the three detected SNPs with the reproductive traits of turkeys were evaluated. The detected polymorphisms were used for marker-trait association analyses. The results of association analysis showed that G5846A on 3’ UTR of VIP has a significant association with LP, EN, TEW, and AFE. The G allele of G5846A was the favourable SNP allele for LP, EN, and TEW traits. The AA genotype of A17690T on intron 2 of VIPR-1 was significantly associated with higher LP, EN, and TEW. AGAA haplotype showed association with higher EN and TEW. These results suggest that the SNPs in 3’-UTR of VIP and intron 2 of VIPR-1 genes may influence egg production traits in turkey hens.Keywords: broodiness, candidate gene, egg production, single nucleotide polymorphism, VIPR-1

Lentiviral gene therapy vectors encoding VIP suppressed diabetes-related inflammation and augmented pancreatic beta-cell proliferation

Type 1 diabetes (T1DM) is an autoimmune condition in which the immune system attacks and destroys insulin-producing beta cells in the pancreas leading to hyperglycemia. Vasoactive intestinal peptide (VIP) manifests insulinotropic and anti-inflammatory properties, which are useful for the treatment of diabetes. Because of its limited half-life due to DPP-4-mediated degradation, constant infusions or multiple injections are needed to observe any therapeutic benefit. Since gene therapy has the potential to treat genetic diseases, an HIV-based lentiviral vector carrying VIP gene (LentiVIP) was generated to provide a stable VIP gene expression in vivo. The therapeutic efficacy of LentiVIP was tested in a multiple low-dose STZ-induced animal model of T1DM. LentiVIP delivery into diabetic animals reduced hyperglycemia, improved glucose tolerance, and prevented weight loss. Also, a decrease in serum CRP levels, and serum oxidant capacity, but an increase in antioxidant capacity were observed in LentiVIP-treated animals. Restoration of islet cell mass was correlated with an increase in pancreatic beta-cell proliferation. These beneficial results suggest the therapeutic effect of LentiVIP is due to the repression of diabetes-induced inflammation, its insulinotropic properties, and VIP-induced beta-cell proliferation.

Transplanted Vasoactive Intestinal Peptide-Secreting Donor Plasmacytoid Dendritic Cells Migrate to Lymphoid Organs and GvHD Target Organs

Introduction: Donor plasmacytoid dendritic cells (pDCs) have important roles in the pathogenesis of graft versus host disease (GvHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Vasoactive intestinal peptide (VIP), a potent anti-inflammatory neuropeptide with pleiotropic effects, has shown promise in managing GvHD through induction of regulatory dendritic cells (Chorny, Blood 2006) and regulatory T cells (Delgado, JLB 2005). Our previous data showed that transplantation of hematopoietic stem cells (HSC) lacking VIP expression in enhanced Th1 polarization and antiviral immunity (Li, JI 2011). Whether VIP produced by pDCs plays a key role in preventing GvHD is the focus of the current study. Method: A reductive allo-HSCT model was established by transplanting purified populations of 5 x 103 hematopoietic stem cells (HSC), 5 x 104 pDCs and 106 T cells from B6 (H-2Kb) to MHC mismatched B10.BR (H-2Kk) recipients. Mice received either VIP knockout pDCs (experimental group) or wild-type pDCs (control). Survival and clinical GvHD scores were monitored for at least 60 days. Serum pro-inflammatory cytokines were measured by luminex on day 3 and day 8. Additional recipients were transplanted for interim analyses of GvHD pathology in histological sections of small intestine and colon on day 8 and day 15. To investigate pDC migration and proliferation status, 5 x 104 luciferase-expressing pDCs, together with 5 x 103 WT B6 HSC, were transplanted to MHC mismatched Balb/c (H2kd) recipients. Bioluminescent imaging was performed on day 14. We used mice carrying an eGFP reporter linked to a VIP promoter to measure VIP production by donor cells in vivo. The construct has the eGFP reporter gene, followed by a polyadenylation sequence, inserted into BAC clone RP23-25A8 at the initiating ATG codon of the first coding exon of the VIP gene, so that eGFP expression is driven by the regulatory sequences of the BAC gene. The BAC is inserted randomly in the genome. We used serial breeding to establish the eGFP-VIP reporter in B6 mice. Bone marrow pDCs were sorted from transgenic eGFP-VIP B6 mice and used in transplant experiments, allowing VIP gene activity from donor-derived pDCs to be detected as GFP expression using confocal microscopy. Results: Compared to recipients of WT pDCs, recipients of VIP-KO pDCs have a significantly lower survival rate with increased GvHD clinical score (Figure 1; *p&lt;0.05). Transplant recipients of VIP-KO donor pDC had higher serum pro-inflammatory cytokine levels on day 3 and day 8 respectively. (Figure 2). At 2 weeks post-transplant donor pDCs migrated primarily to the spleen, with limited presence of donor pDCs in the gastrointestinal tract and lung (Figure 3). Compared to mice transplanted with WT pDCs, recipients of VIP-KO pDCs had increased donor T cell migration to the lung and paw, which are chronic GvHD target organs after two weeks. (Figure 4; *p&lt;0.05). When stimulated with IFN-g, eGFP-VIP transgenic pDCs have activation of the VIP gene promoter in vitro, as detected using eGFP (Figure 5). Confocal microscopy data showed that pDCs have activated the VIP promoter and secreted more VIP following stimulation by IFN-g, consistent with VIP up-regulation by the inflammatory mileu in allo-transplant recipients. Conclusions: These data show that lack of VIP secretion by donor pDCs resulted in lower survival rates and higher GvHD scores in allo-BMT recipients. Recipients of VIP KO donor pDC had increased donor T cell proliferation in GvHD target organs and increased GvHD clinical signs. The major site of donor pDCs migration in recipients is spleen, suggesting that pDCs may interact with other lymphoid cells, such as T cells, inducing a more tolerogenic environment. Donor pDCs were also found, to a lesser extent, in the lung and gastrointestinal tract, which are both GvHD target organs. Thus, pDCs may protect recipients from GvHD by limiting the activity of alloreactive T cells at these sites. The mechanism by which VIP-secreting donor pDCs regulate GvHD will be discussed. Disclosures Waller: Amgen: Consultancy; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Other: Travel expenses, Research Funding; Cerus Corporation: Other: Stock, Patents &amp; Royalties; Chimerix: Other: Stock; Cambium Oncology: Patents &amp; Royalties: Patents, royalties or other intellectual property ; Kalytera: Consultancy.

Changes in VIP-, SP- and CGRP- like immunoreactivity in intramural neurons within the pig stomach following supplementation with low and high doses of acrylamide

Acrylamide is one of the food toxins to which the human body is exposed. Although researchers’ interest in acrylamide has been growing in recent years, the knowledge of its effect on the gastrointestinal tract, especially on intramural neurons which form the enteric nervous system is scarce. The aim of this experiment was to determine the influence of acrylamide, administered at doses equivalent to the human tolerable daily intake (TDI, 0.5 μg/kg b.w./day) and ten times higher than the TDI (5 μg/kg b.w./day), on the distribution of vasoactive intestinal peptide (VIP), substance P (SP), and calcitonin gene related peptide (CGRP) in intramural neurons of the domestic pig stomach. Using double immunofluorescent labelling we revealed that the ENS neurons underwent adaptive changes in response to the supplementation of acrylamide, which manifested themselves as increased expression of VIP, SP and CGRP, both in intramural neurons and by an increase in the nerve density in submucous and muscular layers in the porcine stomach. These substances take part in defensive reactions of neurons and transmission of sensory reactions may play an important role in protecting the stomach against the harmful effect of acrylamide. Moreover, it has been shown that acrylamide induces a significant response of ENS neurons even in TDI dose, which suggests that it is not neutral to the body. These findings may be the basis for further toxicological studies addressing the question if currently permitted minimal content of acrylamide in the food does jeopardize the health of human consumers?

Trophoblast VIP deficiency entails immune homeostasis loss and adverse pregnancy outcome in mice.

Immune homeostasis maintenance throughout pregnancy is critical for normal fetal development. Trophoblast cells differentiate into an invasive phenotype and contribute to the transformation of maternal arteries and the functional shaping of decidual leukocyte populations. Insufficient trophoblast invasion, inadequate vascular remodeling, and a loss of immunologic homeostasis are associated with pregnancy complications, such as preeclampsia and intrauterine growth restriction. Vasoactive intestinal peptide (VIP) is a pleiotropic neuropeptide synthetized in trophoblasts at the maternal-placental interface. It regulates the function of trophoblast cells and their interaction with decidual leukocytes. By means of a murine model of pregnancy in normal maternal background with VIP-deficient trophoblast cells, here we demonstrate that trophoblast VIP is critical for trophoblast function: VIP gene haploinsufficiency results in lower matrix metalloproteinase 9 expression, and reduced migration and invasion capacities. A reduced number of regulatory T cells at the implantation sites along with a lower expression of proangiogenic and antiinflammatory markers were also observed. Findings detected in the implantation sites at early stages were followed by an abnormal placental structure and lower fetal weight. This effect was overcome by VIP treatment of the early pregnant mice. Our results support the relevance of trophoblast-synthesized VIP as a critical factor in vivo for trophoblast-cell function and immune homeostasis maintenance in mouse pregnancy.-Hauk, V., Vota, D., Gallino, L., Calo, G., Paparini, D., Merech, F., Ochoa, F., Zotta, E., Ramhorst, R., Waschek, J., Leirós, C. P. Trophoblast VIP deficiency entails immune homeostasis loss and adverse pregnancy outcome in mice.

HIV-based lentivirus-mediated vasoactive intestinal peptide gene delivery protects against DIO animal model of Type 2 diabetes.

Type 2 diabetes mellitus (T2DM) is characterised by insulin resistance, glucose intolerance and beta cell loss leading to hyperglycemia. Vasoactive intestinal peptide (VIP) has been regarded as a novel therapeutic agent for the treatment of T2DM because of its insulinotropic and anti-inflammatory properties. Despite these beneficial properties, VIP is extremely sensitive to peptidases (DPP-4) requiring constant infusion or multiple injections to observe any therapeutic benefit. Thus, we constructed an HIV-based lentiviral vector encoding human VIP (LentiVIP) to test the therapeutic efficacy of VIP peptide in a diet-induced obesity (DIO) animal model of T2DM. VIP gene expression was shown by immunocytochemistry (ICC) and VIP peptide secretion was confirmed by ELISA both in HepG2 liver and MIN6 pancreatic beta cell lines. Functional properties of VIP were demonstrated by cAMP production assay and glucose-stimulated insulin secretion test (GSIS). Intraperitoneal (IP) delivery of LentiVIP vectors into mice significantly increased serum VIP concentrations compared to control mice. Most importantly, LentiVIP delivery in DIO animal model of T2DM resulted in improved insulin sensitivity, glucose tolerance and protection against STZ-induced diabetes in addition to reduction in serum triglyceride/cholesterol levels. Collectively, these data suggest LentiVIP delivery should be evaluated as an experimental therapeutic approach for the treatment of T2DM.

Co-expression of vasoactive intestinal peptide and protein gene product 9.5 surrounding the lumen of human Schlemm's canal

Previous studies of aqueous humor outflow have focused primarily on resistance at the trabecular meshwork (TM), and little is known about the function of Schlemm's canal (SC). Here, we aimed to investigate whether SC is innervated by the peripheral nervous system. Ten eye specimens from eight donors were processed for histological analysis. CD31 was used to identify SC, after which we used protein gene product (PGP) 9.5 as a marker to detect nerve fibers around SC. We then characterized the nerves by double staining for PGP9.5 and sympathetic nerve markers, such as tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DβH), or the parasympathetic marker vasoactive intestinal peptide (VIP), as well as sensory nerve marker calcitonin gene-related peptide (CGRP) and vesicular glutamate transporter 2 (VGLUT2). Immunohistochemistry and immunofluorescence were also performed to detect the expression of γ-epithelial Na+ channel (γ-ENaC) in SC. We found that different markers were expressed in the anterior chamber angle, with the luminal surface of SC were only positive stained for PGP9.5, VIP, and γ-ENaC. CGRP and VGLUT2 were expressed in TM and scleral spur (SS), whereas TH and DβH were absent in both TM and SC. Furthermore, PGP9.5 was co-expressed with VIP and γ-ENaC in the region surrounding the SC as well as in SS. Our findings indicate that the peripheral nerves anatomically spread in the tissues around the SC and the local nerve fibers may be parasympathetic or sensory rather than sympathetic.

Vasoactive intestinal peptide gene polymorphisms, associated with its serum levels, predict treatment requirements in early rheumatoid arthritis

We previously reported that early arthritis (EA) patients with low vasoactive intestinal peptide (VIP) serum levels demonstrate a worse clinical disease course. In this study, we analysed whether variants in the VIP gene correlated with its serum levels and clinical EA parameters. The VIP gene was sequenced in patients with extremely high/low VIP levels, measured by enzyme immunoassay. Sixteen single nucleotide polymorphisms (SNPs) were differentially distributed between both groups, which were subsequently genotyped in two patients’ sets. We observed that patients with rs688136 CC genotype showed higher VIP levels in both discovery (n = 91; p = 0.033) and validation populations (n = 131; p = 0.007). This effect was attenuated by the presence of minor alleles rs35643203 and rs12201140, which showed a clear trend towards low VIP level association (p = 0.118 and p = 0.049, respectively). Functional studies with miR-205-5p, which has a target site in the 3′ UTR close to rs688136, revealed a miRNA-mediated regulatory mechanism explaining the higher VIP gene expression in homozygous patients. Moreover, patients with an rs688136 CC genotype and no minor alleles of the other polymorphisms required less treatment (p = 0.009). We concluded that the identification of polymorphisms associated with VIP serum levels would complement the clinical assessment of the disease severity in rheumatoid arthritis patients.

Enhanced Mortality to Metastatic Bladder Cancer Cell Line MB49 in Vasoactive Intestinal Peptide Gene Knockout Mice.

To identify if the absence of the vasoactive intestinal peptide (VIP) gene enhances susceptibility to death from metastatic bladder cancer, two strains of mice were injected with MB49 murine bladder cancer cells. The growth and spread of the cancer was measured over a period of 4 weeks in C57BL/6 mice and 5 weeks in VIP knockout (KO) mice. A Kaplan–Meier plot was constructed to compare control C57BL/6 mice and C57BL/6 mice with MB49 vs. VIP KO controls and VIP KO mice with MB49. The wild-type (WT) strain (C57BL/6) contained the VIP gene, while the other strain, VIP knockout backcrossed to C57BL/6 (VIP KO) did not and was thus unable to endogenously produce VIP. VIP KO mice had increased mortality compared to C57BL/6 mice at 4 weeks. The number of ulcers between both groups was not statistically significant. In vitro studies indicated that the presence VIP in high doses reduced MB49 cell growth, as well as macrophage inhibitory factor (MIF), a growth factor in bladder cancer cells. These findings support the concept that VIP may attenuate susceptibility to death from bladder cancer, and that it exerts its effect via downregulation of MIF.

Reproductive axis gene regulation during photostimulation and photorefractoriness in Yangzhou goose ganders

BackgroundThe Yangzhou goose is a long-day breeding bird that has been increasingly produced in China. Artificial lighting programs are used for controlling its reproductive activities. This study investigated the regulations of photostimulation and photorefractoriness that govern the onset and cessation of the breeding period.ResultsIncreasing the daily photoperiod from 8 to 12 h rapidly stimulated testis development and increased plasma testosterone concentrations, with peak levels being reached 2 months after the photoperiod increase. Subsequently, testicular activities, testicular weight, spermatogenesis, and plasma testosterone concentrations declined steadily and reached to the nadir at 5 months after the 12-hour photoperiod. Throughout the experiment, plasma concentrations of triiodothyronine and thyroxine changed in reciprocal fashions to that of testosterone. The stimulation of reproductive activities caused by the increasing photoperiod was associated with increases in gonadotropin-releasing hormone (GnRH), but decreases in gonadotropin-inhibitory hormone (GnIH) and vasoactive intestinal peptide (VIP) gene messenger RNA (mRNA) levels in the hypothalamus. In the pituitary gland, the levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) mRNA abruptly increased during the longer 12-hour photoperiod. The occurrence of photorefractoriness was associated with increased GnIH gene transcription by over 250-fold, together with increased VIP mRNA levels in the hypothalamus, and then prolactin and thyroid-stimulating hormone in the pituitary gland. FSH receptor, LH receptor, and StAR mRNA levels in the testis changed in ways paralleling those of testicular weight and testosterone concentrations.ConclusionsThe seasonal reproductive activities in Yangzhou geese were directly stimulated by a long photoperiod via upregulation of GnRH gene transcription, downregulation of GnIH, VIP gene transcription, and stimulation of gonadotrophin. Development of photorefractoriness was characterized by hyper-regulation of GnIH gene transcription in the hypothalamus, in addition of upregulation of VIP and TRH gene transcription, and that of their receptors, in the pituitary gland.

Role of the serotonergic axis in the reproductive failure associated with aging broiler breeder roosters

Reproductive failure associated with aging is a well-known phenomenon. However, the mechanism by which this failure occurs in broiler breeder roosters is still unclear. A previous study conducted in our laboratory, comparing young and aging broiler breeder roosters, demonstrated an elevation in hypothalamic vasoactive intestinal peptide (VIP) and pituitary prolactin (PRL) gene expression accompanied by a deterioration of gonadal axis function. This resulted in a decrease in semen-quality variables as roosters aged. The objective of this study was to examine the involvement of the serotonergic axis in the age-associated reproductive failure in broiler breeder roosters. Cobb roosters aged 64 wk were divided into 3 groups (n = 20 each): parachlorophenylalanine (PCPA) administration, active immunization against chicken VIP, and controls. At 69 wk of age, each group was divided into 2 equal subgroups: 1 received ovine PRL and the other served as controls. Weekly semen volume, concentration and motility, and plasma testosterone, estradiol, and PRL concentrations were examined. At the end of the experiment, roosters were euthanized, testes were weighed, and hypothalamus and pituitary were removed to assay the expression of genes encoding hypothalamic GnRH-I, pituitary FSH, pituitary LH, hypothalamic VIP, and pituitary PRL. Both PCPA administration and active immunization against chicken VIP significantly increased testis weight, semen volume, sperm concentration, ejaculation grade, plasma testosterone level, and GnRH-I, FSH and LH gene expression compared with controls (P ≤ 0.05). In addition, a decrease in plasma estradiol and PRL concentrations and VIP and PRL gene expression was observed in PCPA- and VIP-immunized birds compared with controls (P ≤ 0.05). Administration of PRL in all groups decreased gonadal axis function and semen-quality variables (P ≤ 0.05). Collectively, these results suggest that the increasing expression levels of the serotonergic axis in aging broiler breeder roosters inhibit proper gonadal function and reproductive performance. This article establishes for the first time the inhibitory role of serotonin on reproduction in aging roosters.

Molecular cloning, characterisation and tissues expression analysis of the goose (Anser cygnoides) vasoactive intestinal peptide (VIP) gene

1. Vasoactive intestinal peptide (VIP) is involved in the control of prolactin (PRL) release and plays a pivotal role as a regulator of reproductive behaviour and neuroendocrine secretion in birds.2. In this study, a 941-bp cDNA fragment covering the complete coding region (CDS) of goose VIP gene was identified. The cDNA contains a 32-bp 5′-untranslated region (UTR), a 603-bp CDS and a 306-bp 3′-UTR containing two ATTTA sequence elements, two polyadenylation signals (AATAAA) and a 25-bp poly (A) tail.3. Seven exons and 6 introns were identified, and both the cDNA and genomic DNA sequences showed high identity with those of other species.4. The sequence analysis indicated that there were two alternatively spliced transcripts the long transcript (VIP-1) encoded both VIP and peptide histidine isoleucine exons and the short one (VIP-2) only encoded VIP.5. RT-PCR analysis indicates that the expression level of the VIP-1 is much lower than that of VIP-2, and that VIP-1 is negligible or absent in muscle, abdominal fat, ovary and spleen, whereas VIP-2 is widely distributed in all the examined tissues.6. A total of 12 single nucleotide polymorphisms (SNPs), including 2 SNPs located in the coding region and 10 variations in intron regions, were identified in goose VIP gene.

Enhancement of catecholamine release from PC12 cells by the traditional Japanese medicine, rikkunshito.

BackgroundRikkunshito is a traditional Japanese herbal medicine that is used to treat appetite loss associated with cancer and other disorders. The formulation contains various constituents that influence cell signaling, and rikkunshito may accordingly affect human homeostasis through multiple regulatory pathways, including those governed by the endocrine system. We investigated the actions of rikkunshito on catecholamine release from PC12 cells, an adrenal chromaffin cell line.MethodsThe actions of rikkunshito on PC12 cells were evaluated by measuring intracellular cAMP levels, tyrosine hydroxylase (TH) and vasoactive intestinal peptide (VIP) mRNA expression levels, and catecholamine levels in the culture medium. The transcriptional activation of VIP gene by rikkunshito was assessed by using a VIP promoter-driven reporter gene assay.ResultsRikkunshito dose-dependently enhanced forskolin-induced elevations in cAMP in PC12 cells, and also increased the gene expression of TH and VIP. The transcriptional activation of VIP gene by rikkunshito was confirmed. Norepinephrine and dopamine secretion into the culture medium of PC12 cells were also dose-dependently augmented by rikkunshito and/or forskolin, but experiments with a protein kinase C (PKC) activator and a phosphodiesterase inhibitor revealed that the effects of rikkunshito were not simply due to the modulation of PKC or phosphodiesterase activity.ConclusionsThese findings suggest that rikkunshito enhances the release of catecholamines by a novel mechanism involving cAMP.

Short communication. An association between the G/A single nucleotide polymorphism within intron II of VIP gene and milk performance traits in dairy cattle

Single nucleotide polymorphisms (SNPs), which are present in the encoding part of the genes responsible for important breeding functions, exert an influence on the cattle’s phenotype since their function is to regulate the genes expression. In this study a G/A single nucleotide polymorphism within intron II of the vasoactive intestinal peptide (VIP) gene was detected. The study covered a herd of 185 Jersey dairy cows from the Wielkopolska Province in Poland. All possible VIP/DraI genotypes determined by using two alleles (AA, AG, GG) were examined in the herd of cows under study. The AA genotype frequency was 0.48; AG 0.22, and GG 0.30. Allele A frequency was 0.592, whereas allele G was 0.408. Analyzed VIP/DraI gene polymorphism with respect to milk utility traits showed slight statistical differences in the percentage of fat and protein content in milk of the animals with different VIP/DraI genotypes. This study could have a significant influence on dairy cattle breeding programs in the future as improvements in genetic selection methods will continue to be important in milking management.

VIP Gene Deletion in Mice Causes Cardiomyopathy Associated with Upregulation of Heart Failure Genes

RationaleVasoactive Intestinal Peptide (VIP), a pulmonary vasodilator and inhibitor of vascular smooth muscle proliferation, is absent in pulmonary arteries of patients with idiopathic pulmonary arterial hypertension (PAH). We previously determined that targeted deletion of the VIP gene in mice leads to PAH with pulmonary vascular remodeling and right ventricular (RV) dilatation. Whether the left ventricle is also affected by VIP gene deletion is unknown. In the current study, we examined if VIP knockout mice (VIP−/−) develop both right (RV) and left ventricular (LV) cardiomyopathy, manifested by LV dilatation and systolic dysfunction, as well as overexpression of genes conducive to heart failure.MethodsWe examined VIP−/−and wild type (WT) mice using Magnetic Resonance Imaging (MRI) for evidence of cardiomyopathy associated with biventricular dilation and wall thickness changes. Lung tissue from VIP−/− and WT mice was subjected to whole-genome gene microarray analysis.ResultsLungs from VIP−/− mice showed overexpression of cardiomyopathy genes: Myh1 was upregulated 224 times over WT, and Mylpf was increased 72 fold. Tnnt3 was increased 105 times and tnnc2 181 fold. Hearts were dilated in VIP−/− mice, with thinning of LV wall and increase in RV and LV chamber size, though RV enlargement varied. Weights of VIP−/− mice were consistently lower.ConclusionsCritically-important heart failure-related genes are upregulated in VIP−/− mice associated with the spontaneous cardiomyopathy phenotype, involving both left and right ventricles, suggesting that loss of the VIP gene orchestrates a panoply of pathogenic genes which are detrimental to both left and right cardiac homeostasis.