Roles of Calcitonin Gene–Related Peptide in Maintenance of Gastric Mucosal Integrity and in Enhancement of Ulcer Healing and Angiogenesis

doi:10.1053/j.gastro.2007.10.001

Gastroenterology

Volume 134, Issue 1, January 2008, Pages 215-225

https://doi.org/10.1053/j.gastro.2007.10.001 Get rights and content

Background & Aims: The gastrointestinal tract is known to be rich in neural systems, among which afferent neurons are reported to exhibit protective actions. We tested whether an endogenous neuropeptide, calcitonin gene–related peptide (CGRP), can prevent gastric mucosal injury elicited by ethanol and enhance healing of acetic acid–induced ulcer using CGRP knockout mice (CGRP^−/−). Methods: The stomach was perfused with 1.6 mmol/L capsaicin or 1 mol/L NaCl, and gastric mucosal injury elicited by 50% ethanol was estimated. Levels of CGRP in the perfusate were determined by enzyme immunoassay. Gastric ulcers were induced by serosal application of absolute acetic acid. Results: Capsaicin inhibited injured area dose-dependently. Fifty percent ethanol containing capsaicin immediately increased intragastric levels of CGRP in wild-type (WT) mice, although 50% ethanol alone did not. The protective action of capsaicin against ethanol was completely abolished in CGRP^−/−. Preperfusion with 1 mol/L NaCl increased CGRP release and reduced mucosal damage during ethanol perfusion. However, 1 mol/L NaCl was not effective in CGRP^−/−. Healing of ulcer elicited by acetic acid in CGRP^−/− mice was markedly delayed, compared with that in WT. In WT, granulation tissues were formed at the base of ulcers, and substantial neovascularization was induced, whereas those were poor in CGRP^−/−. Expression of vascular endothelial growth factor was more markedly reduced in CGRP^−/− than in WT. Conclusions: CGRP has a preventive action on gastric mucosal injury and a proangiogenic activity to enhance ulcer healing. These results indicate that the CGRP-dependent pathway is a good target for regulating gastric mucosal protection and maintaining gastric mucosal integrity.

Section snippets

Animals

A strain of 8-week-old male CGRP receptor knockout mice (CGRP^−/−)1 and their wild-type counterparts (WT, male) were used. To estimate immunohistochemical localization of CGRP in gastric mucosa, we isolated gastric specimens under normal conditions from WT mice, and the sections were stained with rabbit polyclonal antibody against CGRP (Cambridge Research Biochemicals, Northwich, UK) as described earlier. All mice were kept in a room maintained at a constant temperature (25° ± 1°C) and humidity

Localization of CGRP in Normal Gastric Mucosa and Reduced Gastric Contents of CGRP in CGRP^−/−

In WT, immunoreactive CGRP was present in the nerve fibers of the gastric mucosa (Figure 1A) and submucosal layer (Figure 1B), whereas the immunoreactive CGRP was hardly detected in the gastric mucosa in CGRP^−/− (data not shown). When CGRP contents in the stomach were determined by enzyme immunoassay in WT, CGRP detected was 13.0 ± 2.1 pg/mg wet tissue of stomach (Figure 1C). By contrast, CGRP content in CGRP^−/− was below the detection limits (0.05 pg/mg wet tissue of stomach) (Figure 1C).

Lack of Capsaicin-Induced Gastric Mucosal Protective Actions Against Ethanol in CGRP^−/−

Discussion

CGRP is a 37-amino acid vasoactive neuropeptide produced by tissue-specific alternative splicing of the primary transcript of the calcitonin/CGRP gene.²¹ Although the biologic properties of CGRP have been studied,²² its pathophysiologic roles are not fully elucidated. Some groups, including ours, have developed CGRP^−/− using gene-targeting strategies.1, 23, 24, 25 Little was examined in CGRP-null mice in terms of the contribution of CGRP to gastric mucosal protection, although cardiovascular

References (37)

P. Holzer
Neural emergency system in the stomach
Gastroenterology
(1998)
T. Green et al.
Calcitonin gene-related peptide and substance P in afferents to the upper gastrointestinal tract in the rat
Neurosci Lett
(1987)
K.A. Sharkey et al.
Sensory substance P innervation of the stomach and pancreasDemonstration of capsaicin-sensitive sensory neurons in the rat by combined immunohistochemistry and retrograde tracing
Gastroenterology
(1984)
H. Hayashi et al.
Transient prevention of ethanol-induced gastric lesion by capsaicin due to release of endogenous calcitonin gene-related peptide in rats
Jpn J Pharmacol
(2001)
K. Boku et al.
Adaptive cytoprotection mediated by prostaglandin I(2) is attributable to sensitization of CRGP-containing sensory nerves
Gastroenterology
(2001)
M. Majima et al.
Prostanoid receptor signaling relevant to tumor growth and angiogenesis
Trends Pharmacol Sci
(2003)
E. Kamoshita et al.
Recruitment of a prostaglandin E receptor subtype, EP3-expressing bone marrow cells is crucial in wound-induced angiogenesis
Am J Pathol
(2006)
S.J. Wimalawansa et al.
Isolation, purification and characterization of beta-hCGRP from human spinal cord
Biochem Biophys Res Commun
(1990)
L. Zhang et al.
Arthritic calcitonin/alpha calcitonin gene-related peptide knockout mice have reduced nociceptive hypersensitivity
Pain
(2001)
J.T. Lu et al.
Mice lacking alpha-calcitonin gene-related peptide exhibit normal cardiovascular regulation and neuromuscular development
Mol Cell Neurosci
(1999)

K. Matuoka et al.

Cultured rabbit gastric epithelial cells producing prostaglandin I₂

Gastroenterology

(1983)

Y. Hori et al.

Potentiation of bradykinin-induced nociceptive response by arachidonate metabolites in dogs

Eur J Pharmacol

(1986)

H. Mizuno et al.

Induction of cyclooxygenase 2 in gastric mucosal lesions and its inhibition by the specific antagonist delays healing in mice

Gastroenterology

(1997)

H. Amano et al.

Adenylate cyclase/protein kinase A signaling pathway enhances angiogenesis through induction of vascular endothelial growth factor in vivo

Jpn J Pharmacol

(2001)

Y. Oh-hashi et al.

Elevated sympathetic nervous activity in mice deficient in alphaCGRP

Circ Res

(2001)

A. Pinto et al.

Effects of adrenomedullin and calcitonin gene–related peptide on airway and pulmonary vascular smooth muscle in guinea-pigs

Br J Pharmacol

(1996)

K. Arai et al.

Endogenous prostaglandin I₂ regulates the neural emergency system through release of calcitonin gene related peptide

Gut

(2003)

T. Saeki et al.

Mild irritant prevents ethanol-induced gastric mucosal microcirculatory disturbances through actions of calcitonin gene-related peptide and PGI₂ in rats

Am J Physiol Gastrointest Liver Physiol

(2004)

Cited by (85)

A biologically active lipid, thromboxane, as a regulator of angiogenesis and lymphangiogenesis
2023, Biomedicine and Pharmacotherapy
Thromboxane (TX) and prostaglandins are metabolites of arachidonic acid, a twenty-carbon unsaturated fatty acid, and have a variety of actions that are exerted via specific receptors. Angiogenesis is defined as the formation of new blood vessels from pre-existing vascular beds and is a critical component of pathological conditions, including inflammation and cancer. Lymphatic vessels play crucial roles in the regulation of interstitial fluid, immune surveillance, and the absorption of dietary fat from the intestine; and they are also involved in the pathogenesis of various diseases. Similar to angiogenesis, lymphangiogenesis, the formation of new lymphatic vessels, is a critical component of pathological conditions. The TP-dependent accumulation of platelets in microvessels has been reported to enhance angiogenesis under pathological conditions. Although the roles of some growth factors and cytokines in angiogenesis and lymphangiogenesis have been well characterized, accumulating evidence suggests that TX induces the production of proangiogenic and prolymphangiogenic factors through the activation of adenylate cyclase, and upregulates angiogenesis and lymphangiogenesis under disease conditions. In this review, we discuss the role of TX as a regulator of angiogenesis and lymphangiogenesis, and its emerging importance as a therapeutic target.
The Physiology and Pharmacology of Diabetic Gastropathy Management
2022, Comprehensive Pharmacology
Chronic diabetes leads to complex biochemical and cellular changes resulting in gastric dysfunction that is often underappreciated by care providers. While gastric symptoms of nausea, vomit, bloating, abdominal pain and early satiety are generally attributed to delay in gastric emptying, the latter poorly correlates with the timing or severity of these symptoms. Other physiological changes including rapid emptying, particularly of liquids, decreased accommodation, poor antropyloral coordination, gastric dysrhythmias, decreased or delayed onset of antral contractions, and hyperalgesia are generally not assessed clinically. A broader term of diabetic gastropathy appears more appropriate to represent the heterogeneous mixture of the various physiological disorders. Moreover, potentially underlying muscular, neuronal, hormonal and inflammatory changes in deeper submucosal structures may explain some of the complex aberrations in chronic diabetes, but remain poorly understood and has largely limited current therapies as empiric and palliative. Also newer understanding of driving forces in the progression of the metabolic syndrome has brought greater understanding for the role of hormonal and surgical therapies. Meanwhile, a better mechanistic understanding of gastric motility and of the various potential pharmacological agents, of which many are undergoing clinical studies as reviewed here, ushers hopes not only for more treatment options, but for optimal individualized therapy.
The effects of CGRP in vascular tissue - Classical vasodilation, shadowed effects and systemic dilemmas
2020, European Journal of Pharmacology
Citation Excerpt :
Furthermore, exogenous CGRP promotes HUVEC secretion of vascular endothelial growth factor (VEGF) in vitro (Lv et al., 2019), which is a key player in the formation of blood vessels and endothelial proliferation (Cai et al., 2006). In vivo, endogenous CGRP has also been found to have proangiogenic activity (Ohno et al., 2008). In CGRP KO mice, basal cardiac microvessel density is decreased in response to transverse aortic constriction-induced cardiac pressure overload leading to cardiac hypertrophy, cardiomyocyte cell death, and eventually, decreased survival rate for the CGRP KO mice, illustrating that CGRP may play a key role in microvascular development (Li et al., 2013).
Vascular tissue consists of endothelial cells, vasoactive smooth muscle cells and perivascular nerves. The perivascular sensory neuropeptide CGRP has demonstrated potent vasodilatory effects in any arterial vasculature examined so far, and a local protective CGRP-circuit of sensory nerve terminal CGRP release and smooth muscle cell CGRP action is evident.
The significant vasodilatory effect has shadowed multiple other effects of CGRP in the vascular tissue and we therefore thoroughly review vascular actions of CGRP on endothelial cells, vascular smooth muscle cells and perivascular nerve terminals. The actions beyond vasodilation includes neuronal re-uptake and neuromodulation, angiogenic, proliferative and antiproliferative, pro- and anti-inflammatory actions which vary depending on the target cell and anatomical location. In addition to the classical perivascular nerve-smooth muscle CGRP circuit, we review existing evidence for a shadowed endothelial autocrine pathway for CGRP.
Finally, we discuss the impact of local and systemic actions of CGRP in vascular regulation and protection from hypertensive and ischemic heart conditions with special focus on therapeutic CGRP agonists and antagonists.
Protective effects of camellia oil (Camellia brevistyla) against indomethacin-induced gastrointestinal mucosal damage in vitro and in vivo
2019, Journal of Functional Foods
Accumulating evidence reveals that nonsteroidal anti-inflammatory drugs (NSAIDs), such as indomethacin, cause oxidative stress and inflammation, which consequently cause gastrointestinal (GI) mucosal damage. Camellia oil, a common edible oil used in Asia, has excellent antioxidative and anti-inflammatory characteristics. Herein, we examined the benefits and protective effects of camellia oil in indomethacin-induced human intestinal Int-407 cells and a mouse model of indomethacin-induced gastric mucosal damage. Camellia oil pretreatment significantly increased cell viability and wound healing and reduced reactive oxygen species production in indomethacin-induced Int-407 cells. In vivo experiments revealed that camellia oil preadministration prevented gastric wound generation by decreasing inflammatory mediators interleukin-6, tumor necrosis factor-α, and cyclooxygenase-2 levels; increasing heme oxygenase-1 antioxidant protein level; and elevating transforming growth factor-β and vascular endothelial growth factor levels in indomethacin-induced BALB/c mice. Thus, camellia oil is a functional dietary oil that prevents oxidative damage and inflammation in NSAID-induced GI mucosal damage.
The impact of low and high doses of acrylamide on the intramural neurons of the porcine ileum
2019, Food and Chemical Toxicology
The present study was designed to assess the influence of acrylamide supplementation, in tolerable daily intake (TDI) dose and a dose ten times higher than TDI, on the neurochemical phenotype of the ENS neurons and synthesis of proinflammatory cytokines in the wall of the porcine ileum. The study was performed on 15 juvenile female Danish Landrace pigs, divided into three groups: C group- animals receiving empty gelatine capsules, LD group- animals receiving capsules with the TDI dose (0.5 μg/kg b.w./day) of acrylamide and HD group- animals receiving acrylamide in a dose ten times higher than the TDI (5 μg/kg b.w./day) in a morning meal for 28 days. It was established that supplementation of acrylamide led to an increase in substance P (SP)-, calcitonin gene-related peptide (CGRP)-, galanin (GAL)- and vesicular acetylcholine transporter (VAChT)-like immunoreactive (LI) neurons as well as a decrease in neuronal nitric oxide synthase (nNOS) -like immunoreactivity in all types of ileum intramural plexuses. Moreover, using ELISA method, an increase in the level of proinflammatory cytokines (IL-1β, IL-6 and TNF- α) was noted in the ileum wall. The results suggest that SP, CGRP, GAL, nNOS and VACHT participate in the regulation of inflammatory conditions induced by acrylamide supplementation.
CGRP/CGRP Receptor Antibodies: Potential Adverse Effects Due to Blockade of Neovascularization?
2019, Trends in Pharmacological Sciences
Citation Excerpt :
The development of chronic inflammation is highly dependent on angiogenesis, which has been particularly observed during chronic proliferative inflammation in subcutaneous surgical sponge implants, a process regulated by endogenous CGRP derived from neuronal systems [4]. VEGF is an important downstream molecule of CGRP receptor signaling, and its upregulation was also observed during healing of skin wounds [57] and gastric ulcer healing [5], both highly dependent on angiogenesis. Healing of acetic acid-induced ulcers is markedly delayed in CGRP-KO animals with reduced angiogenesis in the granulation tissues, which is new connective tissue formed at the base of ulcers [5].
Migraine is a severe neurological disorder in which calcitonin gene-related peptide (CGRP) is a key molecule in pathophysiology. Neuronal system-derived CGRP enhances neovascularization in several important pathological conditions and sends a cue to the vascular system. In 2018, the FDA approved erenumab and fremanezumab, antibodies against CGRP receptor and CGRP, as the first new class of drugs for migraine. Treatment of migraine with these antibodies requires great care because neovascularization-related adverse effects may be induced in some patients. Here, we focus on enhancement of neovascularization by CGRP and discuss possible adverse effects resulting from blocking neovascularization. We also suggest that CGRP antibodies may also be used as novel antitumor agents by suppressing tumor-associated angiogenesis.

View all citing articles on Scopus

: The authors thank Michiko Ogino and Osamu Katsumata for technical assistance. This work was supported by research grants (#12470529 and #12670094), by a High-tech Research Center grant, by an Academic Frontier Project grant, and by a grant from The 21st Century COE Program, from the Ministry of Education, Culture, Sports, Science and Technology. This study was also supported by an Integrative Research Program of the Graduate School of Medical Science, Kitasato University. We are also grateful to Mr. C.W.P. Reynolds for linguistic assistance in the preparation of the manuscript.

View full text

Basic–Alimentary TractRoles of Calcitonin Gene–Related Peptide in Maintenance of Gastric Mucosal Integrity and in Enhancement of Ulcer Healing and Angiogenesis

Section snippets

Animals

Localization of CGRP in Normal Gastric Mucosa and Reduced Gastric Contents of CGRP in CGRP−/−

Lack of Capsaicin-Induced Gastric Mucosal Protective Actions Against Ethanol in CGRP−/−

Discussion

Gastroenterology

Neurosci Lett

Gastroenterology

Jpn J Pharmacol

Gastroenterology

Trends Pharmacol Sci

Am J Pathol

Biochem Biophys Res Commun

Pain

Mol Cell Neurosci

Gastroenterology

Eur J Pharmacol

Gastroenterology

Jpn J Pharmacol

Elevated sympathetic nervous activity in mice deficient in alphaCGRP

Circ Res

Effects of adrenomedullin and calcitonin gene–related peptide on airway and pulmonary vascular smooth muscle in guinea-pigs

Br J Pharmacol

Endogenous prostaglandin I2 regulates the neural emergency system through release of calcitonin gene related peptide

Gut

Mild irritant prevents ethanol-induced gastric mucosal microcirculatory disturbances through actions of calcitonin gene-related peptide and PGI2 in rats

Am J Physiol Gastrointest Liver Physiol

Basic–Alimentary Tract
Roles of Calcitonin Gene–Related Peptide in Maintenance of Gastric Mucosal Integrity and in Enhancement of Ulcer Healing and Angiogenesis

Localization of CGRP in Normal Gastric Mucosa and Reduced Gastric Contents of CGRP in CGRP^−/−

Lack of Capsaicin-Induced Gastric Mucosal Protective Actions Against Ethanol in CGRP^−/−

Endogenous prostaglandin I₂ regulates the neural emergency system through release of calcitonin gene related peptide

Mild irritant prevents ethanol-induced gastric mucosal microcirculatory disturbances through actions of calcitonin gene-related peptide and PGI₂ in rats