Plasma Calcitonin Gene-related Peptide Levels Research Articles

Signalling of the neuropeptide calcitonin gene-related peptide (CGRP) through RAMP1 promotes liver fibrosis via TGFβ1/Smad2 and YAP pathways

The liver is innervated by primary sensory nerve fibres releasing the neuropeptide calcitonin gene-related peptide (CGRP). Elevated plasma levels of CGRP have been found in patients with liver fibrosis or cirrhosis. We hypothesised that signalling of CGRP and its receptors might regulate liver fibrosis and propose a novel potential target for the treatment. In this study, hepatic expression of CGRP and its receptor component, the receptor activity-modifying protein 1 (RAMP1), was dramatically increased in diseased livers of patients. In a murine liver fibrosis model, deficiency of RAMP1 resulted in attenuated fibrogenesis characterized by less collagen deposition and decreased activity of hepatic stellate cells (HSC). Mechanistically, activity of the TGFβ1 signalling core component Smad2 was severely impaired in the absence of RAMP1, and Yes-associated protein (YAP) activity was found to be diminished in RAMP1-deficient liver parenchyma. In vitro, stimulation of the HSC line LX-2 cells with CGRP induces TGFβ1 production and downstream signalling as well as HSC activation documented by increased α-SMA expression and collagen synthesis. We further demonstrate in LX-2 cells that CGRP promotes YAP activation and its nuclear translocation subsequent to TGFβ1/Smad2 signals. These data support a promotive effect of CGRP signalling in liver fibrosis via stimulation of TGFβ1/Smad2 and YAP activity.

Nape seven needles combined with pressing moxibustion for cervical vertigo: a randomized controlled trial

To observe the clinical effect of nape seven needles combined with pressing moxibustion for cervical vertigo (CV). A total of 70 patients with CV were randomized into an observation group and a control group, 35 cases in each group. In the observation group, nape seven needles combined with pressing moxibustion was delivered, once a day, 6 times a week, for consecutive 2 weeks. In the control group, betahistine hydrochloride tablet and aceclofenac dispersible tablet were given orally, for 2 weeks and 3 days respectively. Before and after treatment, the evaluation scale for cervical vertigo (ESCV) score was observed, the plasma levels of neuropeptide Y (NPY), endothelin-1 (ET-1) and calcitonin gene related peptide (CGRP) were detected, the hemorheologic and hemodynamic indexes were measured, and the clinical efficacy was evaluated after treatment in the two groups. After treatment, the scores of dizziness, daily life and work ability, psychological and social adaptability, and headache, as well as the total scores of ESCV were increased compared with those before treatment (P<0.01, P<0.05) in the two groups, and the score and total score of neck and shoulder pain of ESCV was increased compared with that before treatment (P<0.01) in the observation group; each sub-item score and total score of ESCV in the observation group were higher than those in the control group (P<0.01, P<0.05). After treatment, the plasma levels of NPY and ET-1 were decreased compared with those before treatment (P<0.01), while the plasma levels of CGRP were increased compared with those before treatment (P<0.01, P<0.05) in the two groups; the plasma levels of NPY and ET-1 in the observation group were lower than those in the control group (P<0.01), the plasma level of CGRP in the observation group was higher than that in the control group (P<0.01). After treatment, the whole blood high shear viscosity, plasma viscosity and whole blood low shear viscosity were decreased compared with those before treatment (P<0.01, P<0.05), the mean velocity of basilar artery (BA), left vertebral artery (LVA) and right vertebral artery (RVA) were increased compared with those before treatment (P<0.05) in the two groups; the whole blood high shear viscosity, plasma viscosity and whole blood low shear viscosity in the observation group were lower than those in the control group (P<0.01), and the mean velocity of BA, LVA and RVA in the observation group were higher than those in the control group (P<0.05). The total effective rate in the observation group was 91.4% (32/35), which was superior to 71.4% (25/35) in the control group (P<0.05). Nape seven needles combined with pressing moxibustion can effectively alleviate the clinical symptoms, and improve the hemorheology and hemodynamics in CV patients.

Plasma calcitonin gene-related peptide levels in idiopathic intracranial hypertension: an exploratory study

BackgroundIdiopathic intracranial hypertension (IIH) is a debilitating condition characterized by increased intracranial pressure often presenting with chronic migraine-like headache. Calcitonin gene-related peptide (CGRP) plays an important pathophysiological role in primary headaches such as migraine, whilst its role in IIH has not yet been established.MethodsThis longitudinal exploratory study included patients with IIH, episodic migraine (EM) in a headache-free interval and healthy controls (HC). Blood samples were collected from a cubital vein and plasma CGRP (pCGRP) levels were measured by standardized ELISA.ResultsA total of 26 patients with IIH (mean age 33.2 years [SD 9.2], 88.5% female, median BMI 34.8 kg/m2 [IQR 30.0–41.4]), 30 patients with EM (mean age 27.6 years [7.5], 66.7% female) and 57 HC (mean age 25.3 years [5.2], 56.1% female) were included. pCGRP levels displayed a wide variation in IIH as well as in EM and HC on a group-level. Within IIH, those with migraine-like headache had significantly higher pCGRP levels than those with non-migraine-like headache (F(2,524) = 84.79; p < 0.001) and headache absence (F(2,524) = 84.79; p < 0.001) throughout the observation period, explaining 14.7% of the variance in pCGRP levels. CGRP measurements showed strong intraindividual agreement in IIH (ICC 0.993, 95% CI 0.987–0.996, p < 0.001). No association was found between pCGRP levels and ophthalmological parameters.ConclusionsAlthough interindividual heterogeneity of pCGRP levels is generally high, migraine-like headache seems to be associated with higher pCGRP levels. CGRP may play a role in the headache pathophysiology at least in a subgroup of IIH.

Elevated plasma levels of calcitonin gene-related peptide in individuals with rosacea: A cross-sectional case-control study.

Understanding the role of calcitonin gene-related peptide (CGRP) in the pathogenesis of rosacea might provide new therapeutic avenues for individuals with this disease. To compare plasma levels of CGRP between individuals with rosacea and healthy controls. In this cross-sectional case-control study conducted in Copenhagen, Denmark, we collected blood samples from the antecubital vein from adults with rosacea and from healthy controls. We enrolled 123 individuals with rosacea and 68 healthy controls. After adjusting for age and sex, plasma levels of CGRP were significantly higher in individuals with rosacea (mean, 95% confidence interval: 140.21 pmol/L, 128.50-151.92 pmol/L), compared with controls (110.77 pmol/L, 99.91-120.14 pmol/L, p = 0.002). Plasma levels of CGRP were not affected by age, sex, BMI, concomitant migraine, rosacea sub- or phenotype, concomitant disease or current treatment. Participants were not age-, sex- and BMI-matched. Elevated plasma levels of CGRP in individuals with rosacea suggest a role of CGRP in the pathogenesis of rosacea. Targeting CGRP signalling might hold therapeutic promise in people affected by this disease. NCT03872050.

Reduced plasma calcitonin gene-related peptide level identified in cluster headache: A prospective and controlled study.

The role of calcitonin gene-related peptide (CGRP) in the cyclic pattern of cluster headache is unclear. To acquire biological insight and to comprehend why only episodic cluster headache responds to CGRP monoclonal antibodies, we examined whether plasma CGRP changes between disease states (i.e. bout, remission and chronic) and controls. The present study is a prospective case-control study. Participants with episodic cluster headache were sampled twice (bout and remission). Participants with chronic cluster headache and controls were sampled once. CGRP concentrations were measured in plasma with a validated radioimmunoassay. Plasma was collected from 201 participants diagnosed with cluster headache according to the International Classification of Headache Disorders, 3rd edition, and from 100 age- and sex-matched controls. Overall, plasma CGRP levels were significantly lower in participants with cluster headache compared to controls (p < 0.05). In episodic cluster headache, CGRP levels were higher in bout than in remission (mean difference: 17.1 pmol/L, 95% confidence interval = 9.8-24.3, p < 0.0001). CGRP levels in bout were not different from chronic cluster headache (p = 0.266). Plasma CGRP is unsuitable as a diagnostic biomarker of cluster headache or its disease states. The identified reduced CGRP levels suggest that CGRPs role in cluster headache is highly complex and future investigations are needed into the modulation of CGRP and its receptors.

Plasma calcitonin gene-related peptide and nerve growth factor as headache and pain biomarkers in recently deployed soldiers with and without a recent concussion.

The objective of this study was to characterize the utility of calcitonin gene-related peptide (CGRP) and nerve growth factor (NGF) as potential biomarkers for headache and pain disorders in the post-military deployment setting. The need to improve recognition, assessment, and prognoses of individuals with posttraumatic headache or other pain has increased interest in the potential of CGRP and NGF as biomarkers. The Warrior Strong Study (NCT01847040) is an observational longitudinal study of United States-based soldiers who had recently returned from deployment to Afghanistan or Iraq from 2009 to 2014. The present nested cross-sectional analysis uses baseline data collected from soldiers returning to Fort Bragg, North Carolina. In total, 264 soldiers (mean (standard deviation [SD] age 28.1 [6.4] years, 230/264 [87.1%] men, 171/263 [65.0%] White) were analyzed. Mean (SD) plasma levels of CGRP were 1.3 (1.1) pg/mL and mean levels of NGF were 1.4 (0.4) pg/mL. Age was negatively correlated with NGF (-0.01 pg/mL per year, p = 0.007) but was not associated with CGRP. Men had higher mean (SD) CGRP plasma levels than women (1.4 95% confidence interval [CI; 1.2] vs. 0.9 95% CI [0.5] pg/mL, p < 0.002, Kruskal-Wallis test). CGRP levels were lower in participants who had a headache at the time of the blood draw (1.0 [0.6] pg/mL vs. 1.4 [1.2] pg/mL, p = 0.024). NGF was lower in participants with continuous pain (all types; 1.2 [0.4] vs. 1.4 [0.4] pg/mL, p = 0.027) and was lower in participants with traumatic brain injury (TBI) + posttraumatic headache (PTH) versus TBI without PTH (1.3 [0.3] vs. 1.4 [0.4] pg/mL, p = 0.021). Otherwise, CGRP and NGF were not associated with migraine-like headache, TBI status, or headache burden as measured by the number of medical encounters in crude or adjusted models. In this exploratory study, plasma levels of NGF and CGRP showed promise as biomarkers for headache and other types of pain. These findings need to be replicated in other cohorts.

The Effect of Group Training or Spinal Orthosis on Quality of Life and Potential Plasma Markers of Pain in Older Women With Osteoporosis. A Randomized Controlled Trial

ObjectivePrimary purpose was to examine the effects of exercise and use of a spinal orthosis on quality of life (QoL). Secondary, to explore the effects of above-mentioned interventions on plasma levels of potential markers of pain: substance P (SP), calcitonin gene-related peptide (CGRP), and interleukin-6 (IL-6). DesignRandomized controlled trial. SettingCommunity-dwelling women in Stockholm. ParticipantsA total of 113 women aged 60-93 years suffering from back pain and self-reported osteoporosis (n=113). InterventionsThe randomized controlled trial was 3-armed: participation in an equipment exercise group, treatment with an activating spinal orthosis or controls. The intervention time was 6 months. Main Outcome Measure(s)QoL (QUALEFFO-41 and SF-36), plasma levels of SP, CGRP, and IL-6 measured at baseline and after 6 months in all 3 arms. ResultsNo improvement of QoL was found. Comparing change in mobility (QUALEFFO-41), the effect in least squares means was lower in the spinal orthosis group compared with controls. In the exercise group, the role emotional score (SF-36) deteriorated during the intervention. Effect size varied between 0.02 and 0.6. There was no change in the levels of CGRP or SP, while IL-6 levels were lower at 6 months in the spinal orthosis group compared with the other groups. At least 1 previous vertebral fracture was verified by X-ray in 46 women. ConclusionThe interventions showed none or negative effect on QoL, which was unexpected. The modest effect size may prompt a cautious interpretation. We found a lowering of IL-6 levels in the spinal orthosis group, but more studies are needed.

Hemodynamic and neurobiological factors for the development of chronic pelvic pain in patients with pelvic venous disorder

ObjectiveThe study was aimed at the identification of hemodynamic and neurobiological factors for the development of chronic pelvic pain (CPP) in patients with pelvic venous disorder (PeVD) using ultrasound, radionuclide, and enzyme immunoassay methods. MethodsThis cohort study included 110 consecutive patients with PeVD and 20 healthy controls. Seventy patients with PeVD had symptoms (CPP in 100% of cases, discomfort in hypogastrium, dyspareunia, vulvar varices, and dysuria), and 40 were asymptomatic. Patients underwent clinical examination, duplex ultrasound study of the pelvic veins and lower extremities, and single-photon emission computed tomography of the pelvic veins with in vivo labeled red blood cells. The prevalence, duration, severity, and pattern of reflux in the pelvic veins, as well as the severity of pelvic venous congestion, were evaluated. Healthy controls underwent only clinical and duplex ultrasound examination. All 130 patients were assessed using enzyme immunoassays to determine plasma levels of calcitonin gene-related peptide (CGRP) and substance P (SP). ResultsSymptomatic patients with PeVD had a higher prevalence of reflux in the ovarian veins (OVs) than asymptomatic ones (45.7% vs 10%, respectively; P = .001) and a greater reflux duration (4.1 ± 1.7 seconds vs 1.4 ± 0.3 seconds; P = .002), although no differences in the OV diameter were found. Similar results were obtained when comparing the diameters of the parametrial veins (PVs) and the duration of reflux in them. Type II/III reflux (greater than 2 seconds) was identified in 41.4% of symptomatic and in only 5% of asymptomatic patients (P = .001). Among patients with CPP, 24.2% had a combined reflux in the OVs, PVs, and uterine veins, and 45.7% had a combined reflux in the OVs and PVs, whereas 90% of patients without CPP had only an isolated reflux in the PVs. The pelvic venous congestion was moderate or severe in 95.7% of patients with CPP and in only 15% patients without CPP (P = .001). In patients with PeVD, the presence of CPP was associated with higher levels of CGRP and SP compared with asymptomatic patients (CGRP: 0.48 ± 0.06 vs 0.19 ± 0.02 ng/mL, respectively, P = .001; SP: 0.38 ± 0.08 vs 0.13 ± 0.03 ng/mL, P = .001). ConclusionsIn patients with PeVD, significant hemodynamic and neurobiological factors for the CPP development were found to be reflux in the pelvic veins greater than 2 seconds, involvement of several venous collectors, and increased plasma levels of CGRP and SP.

High plasma calcitonin gene-related peptide and serum pituitary adenylate cyclase-activating polypeptide levels in patients with neuropathic pain

IntroductionBased on animal studies, calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP) are thought to play a role in neurobiological events such as neuropathic pain, neuroprotection, neurotransmission, neural plasticity, and neurotrophic effects. The aim of the study is to investigate whether there is a change in the blood level of CGRP and PACAP in patients with neuropathic pain and to look for clues about the utility of these peptides as pharmacological targets in the treatment of neuropathic pain in humans. MethodsThe study included 60 polyneuropathy patients with neuropathic pain, 30 polyneuropathy patients without neuropathic pain (NNP) and 29 healthy subjects as control group. Polyneuropathy patients with neuropathic pain were divided into two groups as diabetic (D-PNP) and non-diabetic polyneuropathy (ND-PNP) patients. Plasma CGRP and serum PACAP levels were measured from venous blood samples of the patients and healthy controls. ResultsThe CGRP level was significantly higher in the D-PNP and ND-PNP groups compared to the control and NNP groups (P<0.05). PACAP levels were significantly higher in the D-PNP and ND-PNP groups compared to the control and NNP groups (P<0.05). There was no significant correlation between CGRP and PACAP levels and neuropathic pain scale (NPS). ConclusionsThis study is the first to demonstrate elevated plasma CGRP and serum PACAP levels in polyneuropathy patients with neuropathic pain. The results of this study are important in terms of showing that both CGRP and PACAP can be new pharmacological targets in the treatment of neuropathic pain and polyneuropathy in humans.

Plasma level of calcitonin gene-related peptide in the diagnosis of episodic migraine with comorbid conditions

Comorbid and co-occurring diseases are risk factors for the progression of episodic migraine to chronic migraine. Biomarkers for migraine could help with diagnosis and treatment selection and monitoring. Aim. To examine the role of the plasma level of calcitonin-gene-related peptide (CGRP) in the diagnosis of episodic migraine in combination with comorbid conditions in the form of cervicalgia and psychoemotional disorders. Materials and methods. The study included 112 patients (84 women, 28 men; mean age 18-58 years), episodic migraine with typical aura – 17, without aura – 60. Patients were divided into 3 groups: I – episodic migraine with cervicalgia (n = 42), II – episodic migraine only (n = 35), III – cervicalgia only (n = 35). The Visual Analogue Scale, Migraine Disability Assessment (MIDAS) score, Headache Impact Test (HIT-6), Neck Disability Index, State-Trait Anxiety Inventory, Beck’s Depression Inventory and the number of days with headache were assessed. The control group consisted of 30 healthy persons to compare the level of CGRP. The serum level of CGRP was determine by enzyme-linked immunosorbent assay using the sandwich ELISA principle. Results. Plasma level of CGRP was higher in groups I and II compared with group III (P = 0.012543), where it did not differ from the control (51.48 ± 5.08 pg/ml). The highest level of CGRP was observed in group I (242.98 ± 5.08 pg/ml) in comparison with group II (145.82 ± 15.38 pg/ml, P = 0.000341). Co-occurring neck-pain in patients with episodic migraine was associated with mood and anxiety disorders. Migraine severity, according to the MIDAS score, was most significantly influenced by plasma level of CGRP, severity of subjective and objective symptoms of headache by the HIT-6, level of State-anxiety and Trait-anxiety, number of days with headache during the last 3 months. Conclusions. The serum level of CGRP is a reliable diagnostic and differential diagnostic laboratory biomarker for episodic migraine. Additional painful syndrome such as cervicalgia influences CGRP level and daily activity, mood and anxiety disorders in episodic migraine patients.

Bariatric Surgery in Migraine patients: CGRP Level and Weight Loss.

Obesity makes migraine more prevalent and severe. Serum level of calcitonin gene-related peptide (CGRP) is associated with the severity of migraine attacks. Although the effect of weight and bariatric surgery has been studied on migraine, the role of CGRP in migraine remission after weight loss surgery needs more investigation. Patients with severe obesity who were bariatric surgery candidates and had been diagnosed with chronic migraine were included in this study. Weight, BMI, number of days with headache in the past 3months, and severity of headaches in 10-point Likert VAS, Migraine Disability Assessment Scale (MIDAS) and Migraine Specific Quality of life (MSQ) questionnaire scores, and serum CGRP levels were evaluated before and within 6-10months after surgery. Sixty patients with chronic migraine with severe obesity were included. Ninety-five percent of patients reported a significantly lower number of attacks (21 to 8, p < 0.001) and severity of headaches within 90-day (7.7 to 4.8, p < 0.001); MIDAS (64.4 to 25.5, p < 0.001) and MSQ scores (44.6 to 26.8, p < 0.001) and CGRP level (252.7 to 130.1, p < 0.001) were significantly reduced after surgery with a mean follow-up of 7.5months. Changes in MIDAS, MSQ, and CGRP were significantly associated with weight-related variables. Bariatric surgery decreases the frequency of migraine attacks, lessens the severity of headaches, and improves the quality of life and disability as well as CGRP plasma levels, suggesting CGRP as a possible etiology in the migraine-obesity link.

Xiongzhi Dilong decoction interferes with calcitonin gene-related peptide (CGRP)-induced migraine in rats through the CGRP/iNOS pathway

To evaluate the effects of Xiongzhi Dilong decoction (XZDLD) and its wind medicine on calcitonin gene-related peptide (CGRP)-induced migraine and explore the mechanism through the CGRP/inducible nitric oxide synthase (iNOS) pathway. Rats were divided into control, model, XZDLD, XZDLD (external wind), XZDLD (internal wind), and olcegepant groups. CGRP was injected into the dura mater to induce a migraine. The frequency of head scratching, cage climbing, and facial grooming was observed. The pain threshold, the levels of CGRP, pituitary adenylate cyclase activating polypeptide (PACAP), substance P (SP), and the plasma protein extravasation (PPE) ratio were measured. The phosphorylation levels of p38, extracellular signal-regulated kinase 1/2 (ERK1/2), and expression of iNOS were detected by western blot. Compared with the model group, the three modified XZDLD groups showed reduced frequency of head scratching and cage climbing in the first 30 min (all P < .05). Facial grooming frequency was reduced in XZDLD and XZDLD (external wind) groups ( P = .0003 and P = .0131, respectively). External wind medicine played a more important role in increasing mechanical pain threshold than internal wind medicine. Moreover, compared with the model group, the three modified XZDLD groups demonstrated reduced plasma levels of CGRP and PACAP (all P < .05). No difference in the SP level was observed among the six groups. XZDLD reduced PPE ratio. XZDLD and XZDLD (external wind) groups suppressed the CGRP/iNOS pathway by inhibiting the p-p38/p38 ratio and the expression of iNOS. No difference in pERK1/2/ERK1/2 ratio was detected among the six groups. XZDLD increases pain threshold, downregulates the expression of CGRP and PACAP, and reduces PPE ratio by inhibiting the CGRP/iNOS pathway. External wind medicine is more effective than internal one on improving facial grooming and head scratching, increasing the mechanical pain threshold, and inhibiting the expression of iNOS.

Unpredictable Sound Stress Model Causes Migraine-Like Behaviors in Mice With Sexual Dimorphism.

Migraine represents one of the major causes of disability worldwide and is more prevalent in women; it is also related to anxiety symptoms. Stress, such as sound stress, is a frequently reported trigger in migraine patients, but the underlying mechanisms are not fully understood. However, it is known that patients with migraine have higher levels of plasma inflammatory cytokines and calcitonin gene-related peptide (CGRP). Stress mediated by unpredictable sound is already used as a model of painful sensitization, but migraine-like behaviors and sexual dimorphism have not yet been evaluated. This study characterized nociception and anxiety-related symptoms after the induction of sound stress in mice. C57BL/6 mice (20–30 g) were exposed to unpredictable sound stress for 3 days, nonconsecutive days. We observed enhanced plasma corticosterone levels on day 1 after stress induction. First, 7 days after the last stress session, mice developed hind paw and periorbital mechanical allodynia, grimacing pain behavior, anxiety-like symptoms, and reduced exploratory behavior. The nociceptive and behavioral alterations detected in this model were mostly shown in female stressed mice at day 7 post-stress. In addition, on day 7 post-stress nociception, these behaviors were consistently abolished by the CGRP receptor antagonist olcegepant (BIBN4096BS, 100 mg/kg by intraperitoneal route) in female and male stressed mice. We also demonstrated an increase in interleukine-6 (IL-6), tumor necrosis factor (TNF-α), and CGRP levels in stressed mice plasma, with female mice showing higher levels compared to male mice. This stress paradigm allows further preclinical investigation of mechanisms contributing to migraine-inducing pain.

CGRP and PACAP-38 play an important role in diagnosing pediatric migraine

BackgroundAn increasing number of studies have suggested that the important role of vasoactive peptides, such as pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38) and calcitonin gene-related peptide (CGRP), in the pathophysiology of migraine seems undeniable in adults, but studies in pediatric migraine patients remain scarce. We prospectively investigated CGRP and PACAP-38 plasma levels in children with migraine during ictal and interictal periods and compared the results between migraine patients with aura and without aura. We were the first to explore the diagnostic value of a combination of CGRP and PACAP-38.MethodsSeventy-six migraine patients aged 4–18 years and seventy-seven age-matched healthy children were included in the study. Plasma vasoactive peptides were measured using the enzyme-linked immunosorbent assay (ELISA). Differences and correlations of groups were analyzed using the independent samples t-test, analysis of variance (ANOVA), Mann-Whitney U test, and multiple linear regression. We also performed logistic regression and receiver operating characteristic curve (ROC) analyses to evaluate the diagnostic value of CGRP and PACAP-38 in pediatric migraine.ResultsPACAP-38 and CGRP levels in migraine patients during the ictal and interictal periods were higher than those in controls (p < 0.001). PACAP-38 and CGRP levels in migraine patients with aura and without aura were higher than those in controls (p < 0.001). PACAP-38 and CGRP were independent risk factors in diagnosing pediatric migraine (adjusted OR (PACAP-38) =1.331, 95% CI: 1.177–1.506, p < 0.001; adjusted OR (CGRP) = 1.113, 95% CI: 1.064–1.165, p < 0.001). Area Under Curve (AUC) comparison: Combination (0.926) > CGRP (0.869) > PACAP-38 (0.867).ConclusionsOur study found almost the same changes in CGRP and PACAP levels in pediatric migraine, suggesting that CGRP and PACAP-38 may work together to play an integral role in pediatric migraine. Higher CGRP levels were found in the ictal phase than in the interictal phase and with aura group than without aura group, indicating that CGRP may take part in the formation of pain and aura. Moreover, ROC and logistic regression analyses suggested that CGRP and PACAP-38 are good indicators to diagnose pediatric migraine, and the combination of CGRP and PACAP-38 was valuable in diagnosing pediatric migraine and differentiating pediatric migraine from non-migraine headaches.Trial registrationThe study has been registered at the Chinese Clinical Trial Registry (ChiCTR2100043157).

Plasma Levels of CGRP During a 2-h Infusion of VIP in Healthy Volunteers and Patients With Migraine: An Exploratory Study

IntroductionThe activation of perivascular fibers and the consequent release of vasoactive peptides, including the vasoactive intestinal polypeptide (VIP), play a role in migraine pathogenesis. A 2-h infusion of VIP provoked migraine, but the mechanisms remain unknown. We investigated whether 2-h infusion of VIP caused alterations in plasma levels of the calcitonin gene-related peptide (CGRP) and whether any changes might be related to the induced migraine attacks.Materials and MethodsWe enrolled individuals with episodic migraine without aura and healthy participants to randomly receive a 2-h infusion of either VIP (8 pmol/kg/min) or placebo (sterile saline) in two randomized, placebo-controlled crossover trials. We collected clinical data and measured plasma levels of VIP and CGRP at fixed time points: at baseline (T0) and every 30 min until 180 min (T180) after the start of the infusion.ResultsBlood samples were collected from patients with migraine (n = 19) and healthy individuals (n = 12). During VIP infusion, mixed effects analysis revealed a significant increase in plasma CGRP (p = 0.027) at T30 (vs. T180, adjusted p-value = 0.039) and T60 (vs. T180, adjusted p-value = 0.027) in patients with migraine. We found no increase in plasma CGRP during VIP-induced migraine attacks (p = 0.219). In healthy individuals, there was no increase in plasma CGRP during VIP (p = 0.205) or placebo (p = 0.428) days.DiscussionPlasma CGRP was elevated in patients with migraine during a prolonged infusion of VIP, but these alterations were not associated with VIP-induced migraine attacks. Given the exploratory design of our study, further investigations are needed to clarify the role of CGRP in VIP-induced migraine.Clinical Trial RegistrationClinicalTrials.gov, identifier: NCT03989817 and NCT04260035.

The neuropeptide calcitonin gene-related peptide links perineural invasion with lymph node metastasis in oral squamous cell carcinoma

ObjectiveAlthough perineural invasion (PNI) is well-known to be correlated with and able to predict lymph node metastasis (LNM) in oral squamous cell carcinoma (OSCC), the clinical and molecular correlation between PNI and LNM has not been elucidated, and preoperative biomarkers for LNM prediction in OSCC are urgently needed.Materials and methodsThe correlation between PNI and LNM was retrospectively evaluated using a cohort of 218 patients diagnosed with OSCC. Candidate neuropeptides were screened based on TCGA database and verified via immunohistochemistry and Western blot analyses. ELISA was used to detect calcitonin gene-related peptide (CGRP) in patient plasma. In vitro assays were used to explore the effects of CGRP on OSCC cells.ResultsOSCC patients with PNI had a higher incidence of LNM (69.86% vs. 26.2%, P < 0.0001, n = 218). CGRP expression was upregulated in the PNI niche and in metastatic lymph nodes, and was correlated with poor overall survival of OSCC patients. Preoperative plasma CGRP levels were higher in OSCC patients (n = 70) compared to healthy donors (n = 60) (48.59 vs. 14.58 pg/ml, P < 0.0001), and were correlated with LNM (P < 0.0001) and PNI (P = 0.0002). Preoperative plasma CGRP levels alone yielded an AUC value of 0.8088 to predict LNM, and CGRP levels combined with preoperative T stage reached an AUC value of 0.8590. CGRP promoted proliferation and migration abilities of OSCC cells, which could be antagonized by either pharmacological or genetic blockade of the CGRP receptor.ConclusionsThe neuropeptide CGRP links PNI and LNM in OSCC, and preoperative plasma CGRP levels can be used to predict LNM in OSCC.

Lars Edvinsson: bench-to-bedside discovery

Lars Edvinsson: bench-to-bedside discovery

CGRP measurements in human plasma - a methodological study.

BackgroundCalcitonin gene-related peptide plasma levels have frequently been determined as a biomarker for primary headaches. However, published data is often inconsistent resulting from different methods that are not precisely described in most studies.MethodsWe applied a well-proven enzyme-linked immunosorbent assay to measure calcitonin gene-related peptide concentrations in human blood plasma, we modified parameters of plasma preparation and protein purification and used calcitonin gene-related peptide-free plasma for standard solutions, which are described in detail.ResultsCalcitonin gene-related peptide levels are stable in plasma with peptidase inhibitors and after deep-freezing. Calcitonin gene-related peptide standard solutions based on synthetic intercellular fluid or pooled plasma with pre-absorbed calcitonin gene-related peptide influenced the measurements but yielded both comprehensible results. In a sample of 56 healthy subjects the calcitonin gene-related peptide plasma levels varied considerably from low (<50 pg/mL) to very high (>500 pg/mL) values. After a 12-hour exposure of these subjects to normobaric hypoxia the individual calcitonin gene-related peptide levels remained stable.ConclusionBuffering with peptidase inhibitors and immediate freezing or processing of plasma samples is essential to achieve reliable measurements. Individuals show considerable differences and partly high calcitonin gene-related peptide plasma levels without detectable pathological reason. Thus plasma measurements are suited particularly to follow calcitonin gene-related peptide levels in longitudinal studies.The use of data for this study was approved by the Ethics Committee of the MedicalUniversity of Innsbruck (https://www.i-med.ac.at/ethikkommission/; EK Nr: 1242/2017).

Plasma calcitonin gene-related peptide (CGRP) in migraine and endometriosis during the menstrual cycle.

ObjectiveMigraine, endometriosis, and the comorbidity of both are frequent pain disorders of special relevance for women. The neuropeptide calcitonin gene‐related peptide (CGRP) is critically involved in migraine, and circumstantial evidence suggests a role in endometriosis. We assessed CGRP levels at different times of menstrual cycle in four groups: healthy women, women with migraine or endometriosis and with the comorbidity of both.MethodsWomen with episodic migraine and women with a histologically confirmed endometriosis were recruited from specialized centers. For CGRP determination with a commercial enzyme immunoassay kit, cubital vein blood samples were collected on menstrual cycle day 2 ± 2 (during menstruation) and on day 15 ± 2 (periovulatory period). The primary endpoint of the study was the absolute difference of CGRP plasma levels between the menstrual and the periovulatory phase of all study groups. Groups were compared using nonparametric test procedures.ResultsA total of 124 women were included in the study. The change of CGRP plasma levels between menstruation and the periovulatory period was different between groups (p = 0.007). Women with comorbid migraine and endometriosis showed an increase of CGRP in the menstrual phase of +6.32 (interquartile range, IQR −3.64–13.60) compared to the periovulatory time, while healthy controls had a decrease of −10.14 (−22.54–0.91, p = 0.004). CGRP levels were different in the periovulatory phase among groups (p = 0.008), with highest values in healthy controls.InterpretationCGRP levels change significantly during the menstrual cycle. Different patterns in women with the comorbidity point to a deviant regulation of CGRP release.

Role of Neurogenic Inflammation, especially Calcitonin Gene-related Peptide (CGRP), in Anaphylactic Reaction of Children with Food Allergy

CGRP has been suggested to mediate neurogenic inflammation in allergic disorders, and induce symptoms which mimic anaphylaxis. In animal models of food allergy(FA), plasma CGRP levels and CGRP-containing nerves are shown to increase, indicating its role in anaphylaxis. Thus, we wanted to know whether CGRP mediates anaphylaxis in children with FA.