Calcitonin gene-related peptide protects the myocardium from ischemia induced by endothelin-1: intravital microscopic observation and (31)P-MR spectroscopic studies

Pathological Roles of Oxidative Stress in Cardiac Microvascular Injury

Cardiac microvascular injury can be a fundamental pathological process that causes high incidence cardiovascular diseases such heart failure, diabetic cardiomyopathy, and hypertension. It is also an independent risk factor for cardiovascular disease. Oxidative stress is a significant pathological process in which the body interferes with the balance of the endogenous antioxidant defense system by producing reactive oxygen species, leading to property changes and dysfunction. It has been demonstrated that oxidative stress is one of the major causes of cardiac microvascular disease. Therefore, additional investigation into the relationship between oxidative stress and cardiac microvascular injury will direct clinical management in the future. In order to give suggestions and support for future in-depth studies, we give a basic overview of the cardiac microvasculature in relation to physiopathology in this review. We also summarize the role of oxidative stress of mitochondrial and non-mitochondrial origin in cardiac microvascular injury and related drug studies.

Drug Safety in Episodic Migraine Management in Adults. Part 2: Preventive Treatments

PURPOSE OF REVIEW

The aim of this review is to aid in decision-making when choosing safe and effective options for preventive migraine medications.

RECENT FINDINGS

In Part 2, we have compiled clinically relevant safety considerations for commonly used migraine prophylactic treatments. Preventive treatment of episodic migraine includes nonspecific and migraine-specific drugs. While medications from several pharmacological classes-such as anticonvulsants, beta-blockers, and antidepressants-have an established efficacy in migraine prevention, they are associated with a number of side effects. The safety of migraine-specific treatments such as anti-CGRP monoclonal antibodies and gepants are also discussed. This review highlights safety concerns of commonly used migraine prophylactic agents and offers suggestions on how to mitigate those risks.

Changes of Endothelin-1 and Calcitonin Gene-Related Peptide Concentrations in Patients with Cervical Radiculopathy after Wrist-Ankle Acupuncture-Moxibustion and Hot Compression with Chinese Herbal Medicine

Objective

This study aimed at investigating the effects of wrist-ankle acupuncture-moxibustion and hot compression with Chinese herbal medicine on pain symptoms, endothelin-1 (ET-1), and calcitonin gene-related peptide (CGRP) concentrations of patients with cervical radiculopathy (CR).

Methods

A total of 82 patients with CR were randomly divided into the study group and control group, with 41 cases in each group. The control group was treated with standard treatment. In addition to standard treatment, the study group was additionally treated with wrist-ankle acupuncture-moxibustion and hot compression with Chinese herbal medicine. The ET-1 and CGRP concentrations in the plasma were measured by the radioimmunoassay method.

Results

The total response rate in the study group and the control group was 97.55% and 82.93%, respectively. The study group showed lower scores of the visual analogue scale (VAS), Northwick Park Neck Pain Questionnaire (NPQ), McGill Pain Questionnaire (MPQ), numbness intensity assessment, and neck disability index (NDI) but higher scores of the Short Form-36 (SF-36) health survey questionnaire than the control group after treatment. Besides, the study group exhibited reduced ET-1 and substance P (SP) concentrations concomitant with increased CGRP and β-endorphin (β-EP) concentrations compared with the control group.

Conclusion

Wrist-ankle acupuncture-moxibustion and hot compression with Chinese herbal medicine could effectively alleviate the pain of CR patients, affect ET-1 and CGRP concentrations, promote the recovery of cervical function, and improve the quality of life.

Reperfusion Cardiac Injury: Receptors and the Signaling Mechanisms

It has been documented that Ca2+ overload and increased production of reactive oxygen species play a significant role in reperfusion injury (RI) of cardiomyocytes. Ischemia/reperfusion induces cell death as a result of necrosis, necroptosis, apoptosis, and possibly autophagy, pyroptosis and ferroptosis. It has also been demonstrated that the NLRP3 inflammasome is involved in RI of the heart. An increase in adrenergic system activity during the restoration of coronary perfusion negatively affected cardiac resistance to RI. Toll-like receptors are involved in RI of the heart. Angiotensin II and endothelin-1 aggravated ischemic/reperfusion injury of the heart. Activation of neutrophils, monocytes, CD4+ T-cells and platelets contributes to cardiac ischemia/reperfusion injury. Our review outlines the role of these factors in reperfusion cardiac injury.

Cardiovascular outcomes in adults with migraine treated with eptinezumab for migraine prevention: pooled data from four randomized, double-blind, placebo-controlled studies

Background

Patients with migraine have an increased relative risk of cardio- and cerebrovascular events, and some migraine treatments may exacerbate this risk. The primary objective of this analysis was to determine whether the rate of cardiovascular adverse events was higher for patients with migraine treated with the migraine-preventive eptinezumab, compared with patients receiving placebo.

Methods

Cardiovascular outcomes in patients with migraine were pooled across four clinical trials (phase 1b, phase 2, and two phase 3 trials) for use of eptinezumab as a preventive migraine treatment for up to 1 year. In all studies, treatment-emergent adverse events (TEAEs) that occurred after the first dose of study treatment (eptinezumab 100 mg, 300 mg, 1000 mg, or placebo) and vital signs were recorded through study completion.

Results

Cardiovascular TEAEs were rare across all four clinical trials, and rates were similar between patients receiving eptinezumab and those receiving placebo. Cardiovascular TEAEs that did occur were mild or moderate in severity; there were no serious adverse events as per FDA definition. Vital signs (systolic blood pressure, diastolic blood pressure, and heart rate) were not meaningfully different across treatment groups over the course of 56 weeks, compared to placebo. Treatment with eptinezumab did not result in significant new or changed cardiovascular medications used concomitantly compared to placebo.

Conclusions

In this post hoc analysis of four clinical trials for eptinezumab, doses of 100 mg, 300 mg, and 1000 mg (more than 3 times the highest approved dose) were not associated with clinically relevant changes in vital signs or significant changes in concomitant cardiovascular medication usage, and had low incidences of cardiovascular TEAEs, comparable to placebo.

Trial registration

NCT01772524 (Study 2), 01/21/2013; NCT02275117 (Study 5), 10/27/2014; NCT02559895 (PROMISE-1), 09/25/2017; NCT02974153 (PROMISE-2), 11/28/2016

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01360-1.

The locus of Action of CGRPergic Monoclonal Antibodies Against Migraine: Peripheral Over Central Mechanisms

Migraine is a complex neurovascular disorder characterized by attacks of moderate to severe unilateral headache, accompanied by photophobia among other neurological signs. Although an arsenal of antimigraine agents is currently available in the market, not all patients respond to them. As Calcitonin Gene-Related Peptide (CGRP) plays a key role in the pathophysiology of migraine, CGRP receptor antagonists (gepants) have been developed. Unfortunately, further pharmaceutical development (for olcegepant and telcagepant) was interrupted due to pharmacokinetic issues observed during the Randomized Clinical Trials (RCT). On this basis, the use of monoclonal antibodies (mAbs; immunoglobulins) against CGRP or its receptor has recently emerged as a novel pharmacotherapy to treat migraines. RCT showed that these mAbs are effective against migraines producing fewer adverse events. Presently, the U.S. Food and Drug Administration approved four mAbs, namely: (i) erenumab; (ii) fremanezumab; (iii) galcanezumab; and (iv) eptinezumab. In general, specific antimigraine compounds exert their action in the trigeminovascular system, but the locus of action (peripheral vs. central) of the mAbs remains elusive. Since these mAbs have a molecular weight of ∼150 kDa, some studies rule out the relevance of their central actions as they seem unlikely to cross the Blood-Brain Barrier (BBB). Considering the therapeutic relevance of this new class of antimigraine compounds, the present review has attempted to summarize and discuss the current evidence on the probable sites of action of these mAbs.

Monoaminergic Receptors as Modulators of the Perivascular Sympathetic and Sensory CGRPergic Outflows

Blood pressure is a highly controlled cardiovascular parameter that normally guarantees an adequate blood supply to all body tissues. This parameter is mainly regulated by peripheral vascular resistance and is maintained by local mediators (i.e., autacoids), and by the nervous and endocrine systems. Regarding the nervous system, blood pressure can be modulated at the central level by regulating the autonomic output. However, at peripheral level, there exists a modulation by activation of prejunctional monoaminergic receptors in autonomic- or sensory-perivascular fibers. These modulatory mechanisms on resistance blood vessels exert an effect on the release of neuroactive substances from the autonomic or sensory fibers that modify blood pressure. Certainly, resistance blood vessels are innervated by perivascular: (i) autonomic sympathetic fibers (producing vasoconstriction mainly by noradrenaline release); and (ii) peptidergic sensory fibers [producing vasodilatation mainly by calcitonin gene-related peptide (CGRP) release]. In the last years, by using pithed rats, several monoaminergic mechanisms for controlling both the sympathetic and sensory perivascular outflows have been elucidated. Additionally, several studies have shown the functions of many monoaminergic auto-receptors and hetero-receptors expressed on perivascular fibers that modulate neurotransmitter release. On this basis, the present review: (i) summarizes the modulation of the peripheral vascular tone by adrenergic, serotoninergic, dopaminergic, and histaminergic receptors on perivascular autonomic (sympathetic) and sensory fibers, and (ii) highlights that these monoaminergic receptors are potential therapeutic targets for the development of novel medications to treat cardiovascular diseases (with some of them explored in clinical trials or already in clinical use).

Sympathetic and Sensory-Motor Nerves in Peripheral Small Arteries

Small arteries, which play important roles in controlling blood flow, blood pressure, and capillary pressure, are under nervous influence. Their innervation is predominantly sympathetic and sensory motor in nature, and while some arteries are densely innervated, others are only sparsely so. Innervation of small arteries is a key mechanism in regulating vascular resistance. In the second half of the previous century, the physiology and pharmacology of this innervation were very actively investigated. In the past 10-20 yr, the activity in this field was more limited. With this review we highlight what has been learned during recent years with respect to development of small arteries and their innervation, some aspects of excitation-release coupling, interaction between sympathetic and sensory-motor nerves, cross talk between endothelium and vascular nerves, and some aspects of their role in vascular inflammation and hypertension. We also highlight what remains to be investigated to further increase our understanding of this fundamental aspect of vascular physiology.

Anti-migraine Calcitonin Gene-Related Peptide Receptor Antagonists Worsen Cerebral Ischemic Outcome in Mice

Objective

Calcitonin gene–related peptide (CGRP) pathway inhibitors are emerging treatments for migraine. CGRP‐mediated vasodilation is, however, a critical rescue mechanism in ischemia. We, therefore, investigated whether gepants, small molecule CGRP receptor antagonists, worsen cerebral ischemia.

Methods

Middle cerebral artery was occluded for 12 to 60 minutes in mice. We compared infarct risk and volumes, collateral flow, and neurological deficits after pretreatment with olcegepant (single or 10 daily doses of 0.1–1mg/kg) or rimegepant (single doses of 10–100mg/kg) versus vehicle. We also determined their potency on CGRP‐induced relaxations in mouse and human vessels, in vitro.

Results

Olcegepant (1mg/kg, single dose) increased infarct risk after 12‐ to 20‐minute occlusions mimicking transient ischemic attacks (14/19 vs 6/18 with vehicle, relative risk = 2.21, p < 0.022), and doubled infarct volumes (p < 0.001) and worsened neurological deficits (median score = 9 vs 5 with vehicle, p = 0.008) after 60‐minute occlusion. Ten daily doses of 0.1 to 1mg/kg olcegepant yielded similar results. Rimegepant 10mg/kg increased infarct volumes by 60% after 20‐minute ischemia (p = 0.03); 100mg/kg caused 75% mortality after 60‐minute occlusion. In familial hemiplegic migraine type 1 mice, olcegepant 1mg/kg increased infarct size after 30‐minute occlusion (1.6‐fold, p = 0.017). Both gepants consistently diminished collateral flow and reduced reperfusion success. Olcegepant was 10‐fold more potent than rimegepant on CGRP‐induced relaxations in mouse aorta.

Interpretation

Gepants worsened ischemic stroke in mice via collateral dysfunction. CGRP pathway blockers might thus aggravate coincidental cerebral ischemic events. The cerebrovascular safety of these agents must therefore be better delineated, especially in patients at increased risk of ischemic events or on prophylactic CGRP inhibition. ANN NEUROL 2020;88:771–784

Emerging Role of Compartmentalized G Protein-Coupled Receptor Signaling in the Cardiovascular Field

G protein-coupled receptors (GPCRs) are cell surface receptors that for many years have been considered to function exclusively at the plasma membrane, where they bind to extracellular ligands and activate G protein signaling cascades. According to the conventional model, these signaling events are rapidly terminated by β-arrestin (β-arr) recruitment to the activated GPCR resulting in signal desensitization and receptor internalization. However, during the past decade, emerging evidence suggest that many GPCRs can continue to activate G proteins from intracellular compartments after they have been internalized. G protein signaling from intracellular compartments is in general more sustained compared to G protein signaling at the plasma membrane. Notably, the particular location closer to the nucleus is beneficial for selective cellular functions such as regulation of gene transcription. Here, we review key GPCRs that undergo compartmentalized G protein signaling and discuss molecular considerations and requirements for this signaling to occur. Our main focus will be on receptors involved in the regulation of important physiological and pathological cardiovascular functions. We also discuss how sustained G protein activation from intracellular compartments may be involved in cellular functions that are distinct from functions regulated by plasma membrane G protein signaling, and the corresponding significance in cardiovascular physiology.

Characterisation of vasodilatory responses in the presence of the CGRP receptor antibody erenumab in human isolated arteries

BACKGROUND

Migraine is associated with activation of the trigeminovascular system, release of calcitonin gene-related peptide (CGRP) and dilation of dural arteries. Novel treatments target calcitonin gene-related peptide or its receptor, which are present in all vascular beds, raising cardiovascular concerns. Erenumab is a human CGRP-receptor antibody approved for the prophylactic treatment of migraine.

METHODS

We characterised the relaxant responses to CGRP in the absence and presence of erenumab (1 μM) in isolated human middle meningeal, internal mammary and (proximal and distal) coronary arteries. Furthermore, in human internal mammary arteries from cardiovascularly-compromised patients, we assessed the pharmacological specificity of erenumab by investigating whether the vasodilatory responses to acetylcholine, sodium nitroprusside, pituitary adenylate cyclase activating polypeptide-38 (PACAP), vasoactive intestinal peptide and nicardipine, along with the vasoconstrictor responses to dihydroergotamine, were modified by erenumab.

RESULTS

Calcitonin gene-related peptide induced concentration-dependent vasodilatory responses in all vessels studied that were significantly antagonised by erenumab. In human internal mammary arteries from cardiovascularly-compromised patients, the responses to acetylcholine, sodium nitroprusside, PACAP, vasoactive intestinal peptide, nicardipine and dihydroergotamine were unaffected by erenumab.

CONCLUSION

Erenumab inhibits calcitonin gene-related peptide-induced vasodilatory responses in human middle meningeal arteries, human internal mammary arteries and human coronary arteries. Moreover, erenumab shows functional specificity as no interaction was observed with the relaxant responses to several vasodilators, nor the dihydroergotamine-dependent vasoconstrictor responses.

Gepants for the treatment of migraine

INTRODUCTION

Migraine is the most common of all neurological disorders. A breakthrough in migraine treatment emerged in the early nineties with the introduction of 5-HT1B/D receptor agonists called triptans. Triptans are used as the standard of care for acute migraine; however, they have significant limitations such as incomplete and inconsistent pain relief, high rates of headache recurrence, class- specific side effects and cardiovascular contraindications. First- and second-generation calcitonin gene-related peptide (CGRP) receptor antagonists, namely gepants, is a class of drugs primarily developed for the acute treatment of migraine. CGRP is the most evaluated target for migraine treatments that are in development.

AREAS COVERED

This article reviews the available data for first- and second-generation CGRP receptor antagonists, the role of CGRPs in human physiology and migraine pathophysiology and the possible mechanism of action and safety of CGRP-targeted drugs.

EXPERT OPINION

Available data suggest that second generation of gepants has clinical efficacy similar to triptans and lasmiditan (5-HT1F receptor agonist) and has improved tolerability. Future studies will assess their safety, especially in specific populations such as patients with cardiovascular disease and pregnant women.

Understanding CGRP and Cardiovascular Risk

Increasing knowledge about the role of calcitonin gene-related peptide (CGRP) in migraine pathophysiology has led to the development of antibodies against this peptide or its receptor. However, CGRP is widely expressed throughout the body, participating not only in pathophysiological conditions but also in several physiological processes and homeostatic responses during pathophysiological events. Therefore, in this chapter, the risks of long-term blockade of the CGRP pathway will be discussed, with focus on the cardiovascular system, as this peptide has been described to have a protective role during ischemic events, and migraine patients present a higher risk of stroke and myocardial infarction.

CGRP, a target for preventive therapy in migraine and cluster headache: Systematic review of clinical data

Introduction

Migraine and cluster headache are challenging to manage, with no tailored preventive medications available. Targeting the calcitonin gene-related peptide (CGRP) pathway to treat these headaches may be the first focused therapeutic option to date, with the potential for promising efficacy.

Methods

We systematically searched PubMed and clinicaltrials.gov for randomized controlled trials investigating the preventive potential of monoclonal antibodies against the CGRP pathway in the treatment of migraine and cluster headache.

Results

The literature search returned a total of 136 records, of which 32 were eligible for review.

Discussion

Clinical data from phase II and III trials of the four monoclonal antibodies targeting the CGRP pathway: Eptinezumab, erenumab, fremanezumab, and galcanezumab, collectively show a positive effect in the preventive treatment of episodic and chronic migraine. Multiple phase II and III trials are under way to further determine the efficacy and safety of this new drug class. It may be particularly important to assess the cardiovascular effects of long-term CGRP blockade. Phase III trials are also currently in progress for the preventive treatment of cluster headache.

Conclusion

Efficacy of anti-CGRP monoclonal antibodies spells a promising future for the many patients suffering from migraine, and possibly also for the smaller but severely-affected population with cluster headache.

Comparison of protein-chip array analysis and traditional ELISAs for biomarker detection of diabetic limb arterial stenosis

The aim of this study was to screen the biomarkers of diabetic limb arterial stenosis. Fasting blood samples of 40 patients with diabetic limb arterial stenosis (experimental group), 40 diabetes patients (diabetic control group), and 40 healthy individuals (healthy control group) were collected. Protein-chip assay analysis and ELISA were used to detect tumor necrosis factor α, interleukin-6, endothelin-1, calcitonin gene-related peptide and high-sensitivity C-reactive protein in the three groups. Protein-chip array analysis and ELISA found consistent results that endothelin-1, tumor necrosis factor α, interleukin-6 and high-sensitivity C-reactive protein in the experimental group were significantly up-regulated while the expression of calcitonin gene-related peptide was down-regulated compared with the healthy control group ( P < 0.01). When compared with the diabetic control group, only markedly increased calcitonin gene-related peptide and interleukin-6 were observed in the experimental group ( P < 0.01). The study suggests that high-throughput protein-chip may be a reliable method to screen biomarkers of diabetic limb arterial stenosis. Calcitonin gene-related peptide and interleukin-6 might be promising biomarkers for diabetic limb arterial stenosis.

Calcitonin gene-related peptide in aerobic exercise induces collateral circulation development in rat ischemia myocardium

PURPOSE

Aerobic exercise may offer favorable effects for coronary perfusion in the myocardial ischemia area, although the underlying molecular mechanisms remain unclear. This study was designed to investigate the effect of aerobic exercise on the collateral circulation in the ischemia myocardium and to evaluate calcitonin gene-related peptide (CGRP) changes during this process.

METHODS AND RESULTS

Wistar rats were randomly divided into 3 groups of 7 rats each: a sham operated group (Sham), a myocardial ischemia-only group (MI) and a MI plus aerobic exercise group (MI+AE). The rat myocardial ischemia model was established by injecting isoprenaline (2mg/kg, i.p.). The aerobic exercise training consisted of swimming (40min/d, 5d/wk) for 4 weeks. At the end-points, after echocardiographic analysis was performed, blood and ischemia myocardium samples were collected and analyzed by ELISA to quantify the CGRP protein. The dorsal root ganglia were isolated and analyzed by reverse transcription polymerase chain reaction (RT-PCR) to examine the CGRP mRNA expression, and ischemia myocardium capillary density was evaluated by immunohistochemistry. Our data showed that the capillary density in the left ventricle and heart function were significantly decreased with decreased CGRP production in the MI rats, which were reversed by aerobic exercise in the MI+AE rats.

CONCLUSION

These results indicate that aerobic exercise may alleviate myocardial ischemia through collateral circulation development with increased CGRP production. CGRP may play an important role in developing the collateral circulation.

Impaired capsaicin-induced relaxation in diabetic mesenteric arteries

AIMS

To investigate capsaicin-induced vasodilation in the diabetic mesenteric arteries.

METHODS

A diabetic rat model was established by intraperitoneal injection of streptozotocin after a 12-h fast. At 12 weeks post-injection, the third branch of the mesenteric artery was dissected out and prepared for vascular reactivity assessment. Capsaicin, capsazepine, N(ω)-nitro-L-arginine methyl ester hydrochloride (L-NAME), sodium nitroprusside (SNP), calcitonin gene-related peptide 8-37 (CGRP8-37), calcitonin gene-related peptide (CGRP), and substance P (SP) were added to investigate subsequent alterations in vascular activity. Plasma and physiological salt solution (PSS) levels of CGRP and SP were measured using radioimmunoassay. The expression of transient receptor potential vanilloid 1 (TRPV1) and phospho-eNOS were determined using Western blot analysis, and nitric oxide (NO) production was measured using a fluorescence probe.

RESULTS

The dilation effect of capsaicin was weaker under the diabetic than control conditions. Capsazepine, L-NAME, and CGRP8-37 attenuated capsaicin-induced vasorelaxation significantly in the diabetic vascular rings. Exogenous CGRP elicited dose-dependent vasodilation in the control arteries, whereas the dilation effect was reduced under diabetic conditions. Plasma and PSS CGRP levels were attenuated and mesenteric artery TRPV1 expression was decreased in the diabetic rats. Phospho-eNOS levels were augmented, and NO production increased following the administration of capsaicin.

CONCLUSIONS

Decreased expression of TRPV1 and associated neuropeptide release contributed to the impaired capsaicin-induced vasodilation in diabetic mesenteric arteries. Furthermore, an endothelium-dependent NO-related pathway was involved in capsaicin-induced vasodilation.