Neural expression and increased lavage fluid levels of secretoneurin in seasonal allergic rhinitis

The Neuropeptide Secretoneurin Exerts a Direct Effect on Arteriogenesis In Vivo and In Vitro

It is well known that nerves modulate the development and remodeling of blood vessels by releasing different neuropeptides and neurotransmitters. Secretoneurin (SN), a neuropeptide located in nerve fibers along blood vessels, acts as a pro-angiogenic agent and induces postnatal vasculogenesis. However, little is known about its involvement in arteriogenesis. In the present study, we tested the hypothesis that SN promotes arteriogenesis in a rat model of hind limb ischemia, as such, we evaluated the effect of this neuropeptide on proliferation and the production of adhesion and chemotaxis molecules in vascular smooth muscle cells (VSMCs), the main component that carries the burden of the transformation of a small arteriole into a large collateral vessel. In vivo, SN-immunoreactive nerve fibers were abundantly distributed in the adventitia of the collateral vessel. Moreover, administration of SN induced cell proliferation in the vascular wall and the infiltration of inflammatory cells/macrophages to promote collateral vessel growth. This was shown by an increased density of arterioles/arteries, together with a well-developed network of collateral vessels, and well-preserved skeletal muscles. In vitro, SN exerted proliferative effects on VSMCs and stimulated these cells to express adhesion molecules. In conclusion, our data demonstrate for the first time that SN acts as a mediator of inflammation, contributing to collateral vessel growth, in addition to directly stimulating cell proliferation in the vascular wall to promote collateral vessel growth in a rat model of hind limb ischemia. Anat Rec, 301:1917-1927, 2018. © 2018 Wiley Periodicals, Inc.

Molecular mechanism of action of K(D)PT as an IL-1RI antagonist for the treatment of rhinitis

K(D)PT curing allergic rhinitis through keeping IL-1RI in close status.

A novel botulinum neurotoxin topical gel: Treatment of allergic rhinitis in rats and comparative safety profile

BACKGROUND

Rhinitis affects a significant proportion of adults and children with typically seasonal or chronic symptoms. Botulinum neurotoxin type A (BoNTA) is a well-known cholinergic antagonist widely used in a number of approved neurological and esthetic indications. This study was designed to assess the therapeutic effect of RT001, a novel topical gel formulation of BoNTA, in the treatment of allergic rhinitis using a rat model and to compare its safety profile with that of an aqueous formulation of BoNTA complex.

METHODS

A rat model of allergic rhinitis was used involving induction of classic rhinitis signs (sneezing and nasal itch) in addition to nasal inflammatory pathology to assess the degree of therapeutic effect of RT001. Comparative safety of RT001 and BoNTA complex was assessed in guinea pigs based on lethality and body weight gain.

RESULTS

Clinical signs of rhinitis were significantly (p < 0.01) relieved after a single intranasal administration of RT001 and resolved to normal baseline levels within 5 days after treatment. Mucosal inflammation characterized by edema, congestion, and vascular dilatation along with increased expression of vasoactive intestinal peptide was noted in control animals after allergy induction, whereas RT001 treatment resolved inflammation to essentially normal baseline levels. Safety studies in guinea pigs via intranasal dosing revealed ∼31-fold greater safety factor for RT001 when compared with BoNTA complex.

CONCLUSION

These results suggest that topical intranasal application of RT001 is effective in relief of clinical signs and inflammatory pathology associated with allergic rhinitis in a rodent model and may provide a safe treatment for rhinitis.

The extended granin family: structure, function, and biomedical implications

The chromogranins (chromogranin A and chromogranin B), secretogranins (secretogranin II and secretogranin III), and additional related proteins (7B2, NESP55, proSAAS, and VGF) that together comprise the granin family subserve essential roles in the regulated secretory pathway that is responsible for controlled delivery of peptides, hormones, neurotransmitters, and growth factors. Here we review the structure and function of granins and granin-derived peptides and expansive new genetic evidence, including recent single-nucleotide polymorphism mapping, genomic sequence comparisons, and analysis of transgenic and knockout mice, which together support an important and evolutionarily conserved role for these proteins in large dense-core vesicle biogenesis and regulated secretion. Recent data further indicate that their processed peptides function prominently in metabolic and glucose homeostasis, emotional behavior, pain pathways, and blood pressure modulation, suggesting future utility of granins and granin-derived peptides as novel disease biomarkers.

Neuropeptide levels in nasal secretions from patients with and without chronic cough

BACKGROUND

The pathophysiology of upper airway cough syndrome is not well understood.

OBJECTIVE

To investigate the levels of neuropeptides found in nasal mucus of subjects with and without the complaint of chronic cough.

METHODS

Preformed nasal mucus from 26 subjects complaining of postnasal drip with chronic cough and 17 without self-reported chronic cough was collected at the time of presentation. The nasal secretions were assayed for 3 neuropeptides-substance P (SP), calcitonin gene-related peptide (CGRP), and Neurokinin A (NKA)-that have been previously linked to chronic cough.

RESULTS

Coughing subjects with postnasal drip have significantly higher levels of CGRP and SP than noncoughing subjects with postnasal drip (69.0 ng vs 4.6 ng, P < .001 and 4.5 ng vs 3.4 ng, P = .004). The differences in NKA levels in nasal secretions between coughing and noncoughing subjects did not reach statistical significance (16.3 ng vs 3.4 ng, P = .067).

CONCLUSIONS

Both CGRP and SP levels are elevated in preformed nasal secretions of coughing subjects when compared with noncoughing subjects. Additional studies are needed to clarify whether CGRP and SP levels in preformed nasal secretions may assist in diagnosis or predicting treatment response in patients presenting with chronic cough.

Sensory neuropeptides are potent chemoattractants for human basophils in vitro

The sensory neuropeptides secretoneurin (SN) and substance P (SP) are involved in "neurogenic" inflammatory processes as they occur in bronchial asthma or allergic rhinitis. A possible interaction with basophils has not been reported to date. Basophils were isolated from healthy donors by magnetic cell sorting technique and migration was explored using Boyden microchemotaxis chambers. SN [10(-8)M] and SP [10(-6) to 10(-8)M] proved to be chemoattractants equally potent to FMLP [10(-8)M] or LPS [10 pg/ml]. Specific anti-SN antibodies and a trypsinization preparation of SN were used to determine the specificity of the SN effect on basophils. The preincubation of basophils with neurokinin-1 (NK-1) or -2 (NK-2) receptor antagonists revealed the SP effect to act via NK-1 receptors in basophils. In addition, we were able to show phosphodiesterases and phosphoinositide-3 kinases to be engaged in the downstream signalling pathway. Our observations reveal for the first time a link between basophils, which are engaged in allergic processes, and the neuropeptides SN and SP. Furthermore, our data might suggest phosphodiesterases or phosphoinositide-3 kinases to be new therapeutic targets for the treatment of allergic diseases such as asthma or allergic rhinitis.

Botulinum toxin therapy in the ovalbumin-sensitized rat

OBJECTIVE

The aim of this study was to determine whether intranasal administration of botulinum toxin type A (BTX-A) could relieve the typical symptoms of allergic rhinitis (AR) and alter substance P (SP)- and vasoactive intestinal peptide (VIP)-immunoreactive (IR) expression in nasal mucosa of AR animals sensitized with ovalbumin (OVA).

METHODS

AR was induced by intraperitoneal injection of OVA followed by its repeated intranasal instillation in female Wistar rats. Some AR animals were intranasally treated with a cotton strip containing BTX-A (10 U per nostril) for 1 h. After BTX-A treatment, OVA was repeatedly instilled in AR and AR + BTX-A groups every 2 days for 10 days. Subsequently, nasal symptoms were evaluated, and nasal secretions collected. Finally, the nasal mucosae of all animals were prepared for histological and immunohistochemical assessment.

RESULTS

BTX-A administration alleviated typical AR symptoms including rhinorrhea, nasal itching and sneezing, and subsequent intranasal repeated challenge with OVA did not trigger AR symptoms. After BTX-A treatment, inflammatory histological characteristics within the nasal mucosa of AR animals were absent, but atrophy of serous glands was observed. BTX-A decreased dense SP-IR and VIP-IR cells and fibers within and beneath the epithelium, around blood vessels and close to serous glands in AR animals.

CONCLUSION

Local BTX-A treatment is an effective method to reduce AR symptoms. BTX-A decreased the excessive SP-IR and VIP-IR expression induced by OVA. Therefore, BTX-A may affect the nasal mucosa via the suppression of neuropeptides, playing a major role in autonomous mucosal innervation in the pathophysiology of AR.

Comparative proteomics of nasal fluid in seasonal allergic rhinitis

A comparative proteomic approach was applied to examine nasal lavage fluid (NLF) from patients with seasonal allergic rhinitis (SAR, n = 6) and healthy subjects (controls, n = 5). NLF samples were taken both before allergy (pollen) season and during season, and proteins were analyzed by two-dimensional gel electrophoresis (2-DE) and matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) after tryptic cleavage. Twenty proteins were selected and quantified. During allergy season, the levels of six sialylated isoforms of PLUNC (palate lung nasal epithelial clone) were lower in SAR patients than controls, as were the levels of six isoforms of von Ebner's gland protein (VEGP), including a previously undescribed form with N-linked glycosylation, and of cystatin S. PLUNC is a new innate immunity protein and VEGP and cystatin S are two endogenous proteinase inhibitors. By contrast, the levels of an acidic form of alpha-1-antitrypsin were higher in SAR patients than controls. One previously unidentified NLF protein was found in all samples from the SAR patients during allergy season but not in any sample before allergy season: this protein was identified as eosinophil lysophospholipase (Charcot-Leyden crystal protein/galactin 10). MS/MS analysis of the N-terminus of the protein showed removal of Met and acetylation of Ser. Altogether, these findings illustrate the potential use of proteomics for identifying protein changes associated with allergic rhinitis and for revealing post-translational modifications of such new potential markers of allergic inflammation.

Effects of the neuropeptide secretoneurin on natural killer cell migration and cytokine release

Secretoneurin has a widespread occurrence in airway mucosal innervation of patients with allergic diseases and may play an important role in the local traffic of immune cells in human airway mucosa. Whether secretoneurin affects natural killer cell migration and cytokine release in vitro was tested. Natural killer cells were obtained from venous blood of healthy donors. Cell migration was studied by micropore filter assays. Signalling mechanisms required for secretoneurin-dependent migration were tested using signalling enzyme blockers. Cytokine release was measured in natural killer cell supernatants by ELISA. Secretoneurin significantly stimulated natural killer cell chemotaxis via activation of phosphatidylinositol 3'-kinase and protein kinase C. IL-2 stimulated natural killer cells showed a stronger response toward secretoneurin than unstimulated cells. Moreover, secretoneurin increased the release of interleukin-5 in a dose-dependent manner but did not affect Th1 cytokine release by natural killer cells. Data suggest that secretoneurin stimulates directed migration of natural killer cells and may modulate Th1/Th2-response via affecting chemokine release. Thus, secretoneurin may play an important role in the early stages of allergic inflammation.

Secretoneurin is released into human airways by topical histamine but not capsaicin

BACKGROUND

The neuropeptide secretoneurin, with potential relevance to leukocyte trafficking, is present in nerves of the nasal mucosa in allergic rhinitis and may be released in response to allergen and histamine exposure. There is no information on the occurrence and mechanisms of release of secretoneurin in healthy human airways.

METHODS

The presence of secretoneurin in nasal biopsies and its release in response to nasal capsaicin and histamine challenges were examined. Symptoms and lavage fluid levels of fucose were recorded as markers of effects in part produced by neural activity. Bronchial histamine challenges followed by sputum induction and analysis of secretoneurin were also carried out.

RESULTS

Nerves displaying secretoneurin immunoreactivity abounded in the nasal mucosa. Nasal capsaicin challenge produced local pain (P <0.05) and increased the levels of fucose (P <0.05), but failed to affect the levels of secretoneurin. Nasal histamine challenge produced symptoms (P <0.05) and increased the mucosal output of secretoneurin (P <0.05) and fucose (P <0.05). Bronchial histamine challenge increased the sputum levels of secretoneurin (P <0.05).

CONCLUSIONS

We conclude that secretoneurin is present in healthy human airways and that histamine evokes its release in both nasal and bronchial mucosae. The present observations support the possibility that secretoneurin is involved in histamine-dependent responses of the human airway mucosa.