NO up-regulates migraine-related CGRP via activation of an Akt/GSK-3β/NF-κB signaling cascade in trigeminal ganglion neurons

AMPK/MTOR/TP53 Signaling Pathway Regulation by Calcitonin Gene-Related Peptide Reduces Oxygen-Induced Lung Damage in Neonatal Rats through Autophagy Promotion

Our previous studies indicated that calcitonin gene-related peptide (CGRP) alleviates hyperoxia-induced lung injury and suggested the possible involvement of autophagy in this process. Herein, we aimed to further explore the potential involvement of tumor protein p53 (TP53) and autophagy in the mode of action of CGRP against hyperoxia-induced lung injury in vitro and in vivo. The study conducted tests on type II alveolar epithelial cells (AECII) and rats that were subjected to hyperoxia treatment or combined treatment of hyperoxia with CGRP, CGRP inhibitor, rapamycin (an autophagy agonist), 3-methyladenine (3-MA, an autophagy inhibitor), TP53 silencing/inhibitor (pifithrin-α), or expression vector/activator (PRIMA-1 (2,2-bis(hydroxymethyl)-3-quinuclidinone)) and their corresponding controls. We found that oxidative stress, apoptosis, and autophagy were all increased by hyperoxia treatment in vitro. However, treating AECII cells with CGRP reversed hyperoxia-induced oxidative stress and apoptosis but further promoted autophagy. In addition, the combined treatment with rapamycin or TP53 silencing with CGRP promoted the effect of CGRP, while contrary results were obtained with combined therapy with 3-MA or TP53 overexpression. In vivo, the number of hyperoxia-induced autophagosomes was promoted in the lung tissue of neonatal rats. Furthermore, hyperoxia increased the expression levels of AMP-activated protein kinase (AMPK) alpha 1 (also known as protein kinase AMP-activated catalytic subunit alpha 1 (PRKAA1)) but inhibited TP53 and mechanistic target of rapamycin (MTOR); these expression trends were regulated by CGRP treatment. In conclusion, we showed that CGRP can attenuate hyperoxia-induced lung injury in neonatal rats by enhancing autophagy and regulating the TP53/AMPK/MTOR crosstalk axis.

Animal Models of Chronic Migraine: From the Bench to Therapy

PURPOSE OF REVIEW

Chronic migraine is a disabling progressive disorder without effective management approaches. Animal models have been developed and used in chronic migraine research. However, there are several problems with existing models. Therefore, we aimed to summarize and analyze existing animal models to facilitate translation from basic to clinical.

RECENT FINDINGS

The most commonly used models are the inflammatory soup induction model and the nitric oxide donor induction model. In addition, KATP openers have also been used in model induction. Based on the above models, some molecular targets have been identified, such as glutamate receptors. However, each model has its shortcomings and characteristics, and there are still some common problems that need to be solved, such as spontaneous headache, evaluation criteria after model establishment, and identification methods. In this review, we summarized and highlighted the advantages and limitations of the currently commonly used animal models of chronic migraine with a special focus on drug discovery and current therapeutic strategies, and discussed the directions that can be worked on in the future.

Association of dietary vitamin C consumption with severe headache or migraine among adults: a cross-sectional study of NHANES 1999-2004

Background

An antioxidant-rich diet has been shown to protect against migraines in previous research. However, little has been discovered regarding the association between migraines and vitamin C (an essential dietary antioxidant). This study assessed the dietary vitamin C intake among adult migraineurs in the United States to determine if there is a correlation between migraine incidence and vitamin C consumption in adults.

Methods

This cross-sectional research encompassed adults who participated in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2004, providing detailed information on their dietary vitamin C intake as well as their history of severe headaches or migraines. The study used weighted multivariable and logistic regression analyses to find an independent connection between vitamin C consumption and severe headache or migraine. Tests of interactions and subgroup analysis were conducted.

Results

Among the 13,445 individuals in the sample, 20.42% had a severe headache or migraine. In fully adjusted models, dietary vitamin C consumption was substantially linked negatively with severe headache or migraine (odds ratio [OR] = 0.94, 95% confidence interval [CI] = 0.91-0.98, p = 0.0007). Compared to quartile 1, quartile 4 had 22% fewer odds of having a severe headache or migraine (OR = 0.78, 95% CI = 0.69-0.89, p = 0.0002). Subgroup analyses showed a significant difference between vitamin C intake and severe headaches or migraines by gender (p for interaction < 0.01).

Conclusion

Reduced risk of severe headaches or migraines may be associated with increased consumption of vitamin C.

Genistein mitigates nitroglycerine-induced migraine: modulation of nitric oxide-mediated vasodilation and oxidative stress

Migraine is a widespread brain condition described by frequent, recurrent episodes of incapacitating, moderate-to-severe headaches with throbbing pain that are usually one-sided. It is the 2nd most debilitating state lived with disability in terms of years, with a prevalence rate of 15-20%. Significant drops in estrogen levels have been associated with triggering acute migraine attacks in certain cases. Phytoestrogens are plant-derived compounds that resemble estrogen in structure, enabling them to imitate estrogen's functions in the body by attaching to estrogen receptors. Thus, the study was aimed to explore the protective effect of genistein against migraine. Moreover, the role of nitric oxide was also studied in the observed effect of genistein. Nitric oxide (NO) is implicated in migraine pathophysiology due to its role in promoting cerebral vasodilation and modulation of pain perception. Exploring L-NAME, a nitric oxide synthase inhibitor in migraine research helps scientists better understand the role of NO in migraine. Nitroglycerine treatment significantly increased the facial-unilateral head pain and spontaneous pain, as evidenced by the increased number of head scratching and groomings. Nitroglycerine treatment also induced anxiogenic behavior in mice. A significant reduction in the number of entries in the light phase and open arm, respectively. Biochemical analysis indicated a significant increase in inflammatory and oxidative stress in the nitroglycerin group. A significant increase and decrease in brain TBARS and GSH were observed with nitroglycerine treatment, respectively. Moreover, nitroglycerine treatment has uplifted the serum TNF-α level. Genistein (20 mg/kg) significantly mitigated the facial-unilateral head pain, spontaneous pain, photophobia, and anxiety-like behavior induced by nitroglycerine. Biochemical analysis showed that genistein (20 mg/kg) significantly abrogated the nitroglycerine-induced lipid peroxidation and increased serum TNF-α level. Genistein treatment also upregulated the brain GSH level and downregulated the serum TNF-α level. The L-NAME-mediated alleviation of the protective effect of genistein might be attributed to the vasodilatory effect of L-NAME. Conclusively, it can be suggested that genistein might provide relief from migraine pain by inhibiting nitric oxide-mediated vasodilation and oxidative stress.

CGRP neuropeptide levels in patients with endometriosis-related pain treated with dienogest: a comparative study

BACKGROUND AND OBJECTIVE

Endometriosis (EM) involves the peripheral nervous system and causes chronic pain. Sensory nerves innervating endometriotic lesions contribute to chronic pain and influence the growth phenotype by releasing neurotrophic factors and interacting with nearby immune cells. Calcitonin gene-related peptide (CGRP), a pain-signaling neurotransmitter, has a significant role. This study examines the effect of Dienogest (DNG), a hormone therapy used for managing EM -related pain, on serum CGRP levels in EM patients.

MATERIALS AND METHODS

The Visual Analog Scale (VAS) assessed pain in diagnosed EM.

INDIVIDUALS

Serum samples were obtained to measure CGRP concentration. Participants received a 2 mg/day oral dose of DNG for six months as prescribed treatment. Additional serum samples were collected after this period to measure CGRP levels.

RESULTS

In the EM group, 6.7%, 33.3%, and 20% had ovarian EM, ovarian plus uterosacral, and ovarian plus bladder, respectively. The EM group showed higher CGRP serum levels than the control group (80.53 ± 16.13 vs. 58.55 ± 6.93, P < 0.0001). Still, after drug administration, CGRP serum levels significantly decreased compared to pre-treatment levels (69.66 ± 11.53 vs. 80.53 ± 16.13, P < 0.05). The EM group showed higher pain compared to the control group (7.93 ± 1.58 vs. 0.13 ± 0.35, P < 0.0001), but after drug administration, pain significantly decreased compared to pre-treatment levels (1.00 ± 2.00 vs. 7.93 ± 1.58, P < 0.05).

CONCLUSION

DNG administration reduces pain and serum CGRP levels in EM patients, offering the potential for innovative treatments and tailored options. Understanding neurotransmitter roles and drug effects can aid in discovering more effective modulators for these pathways.

Restoring brain health: Electroacupuncture at GB20 and LR3 for migraine mitigation through mitochondrial restoration

BACKGROUND

Electroacupuncture (EA) is a promising alternative therapy for migraine, with mitochondrial dysfunction hypothesized as a pivotal mechanism in migraine pathophysiology. This research endeavors to investigate the therapeutic potential of EA in addressing migraines and shed light on the associated mechanisms linked to mitochondrial anomalies.

MATERIALS AND METHODS

Migraine in rats was induced by 10 mg/kg nitroglycerin, followed by 2/15 Hz EA treatment at GB20 and LR3. Nociceptive behavior was recorded via a camera and analyzed using EthoVision XT 12.0 software. The hind-paw withdrawal threshold was assessed using the von Frey test. We assessed the levels of calcitonin gene-related peptide (CGRP), nitric oxide (NO), and endothelin (ET) - key parameters in migraine pathophysiology using immunohistochemistry and enzyme-linked immunosorbent assay. Mitochondrial morphology in brain tissues was observed through transmission electron microscopy. Reactive oxygen species (ROS) level in mitochondria was measured by flow cytometry. The levels of PINK1 and Parkin were assessed using Western blot analysis.

RESULTS

EA at GB20 and LR3 decreased nociceptive behaviors (resting and grooming) and increased exploratory and locomotor behaviors in migraine rats. The hind-paw withdrawal threshold in migraine rats was significantly elevated following EA treatment. Post-EA treatment, levels of CGRP and NO decreased, while ET level increased, suggesting an alteration in pain and vascular physiology. Notably, EA treatment mitigated the mitochondrial damage and reduced ROS level in the brain tissues of migraine rats. EA treatment upregulated the expression of PINK1 and Parkin in migraine rats.

CONCLUSION

EA at GB20 and LR3 may treat migraine by alleviating PINK1/Parkin-mediated mitochondrial dysfunction.

CGRP Antagonism and Ketogenic Diet in the Treatment of Migraine

The study of migraine is based on the complexity of the pathology, both at the pathophysiological and epidemiological levels. Although it affects more than a billion people worldwide, it is often underestimated and underreported by patients. Migraine must not be confused with a simple headache; it is a serious and disabling disease that causes considerable limitations in the daily life of afflicted people, including social, work, and emotional effects. Therefore, it causes a daily state of suffering and discomfort. It is important to point out that this pathology not only has a decisive impact on the quality of life of those who suffer from it but also on their families and, more generally, on society as a whole. The clinical picture of migraine is complex, with debilitating unilateral or bilateral head pain, and is often associated with characteristic symptoms such as nausea, vomiting, photophobia, and phonophobia. Hormonal, environmental, psychological, dietary, or other factors can trigger it. The present review focuses on the analysis of the physiopathological and pharmacological aspects of migraine, up to the correct dietary approach, with specific nutritional interventions aimed at modulating the symptoms. Based on the symptoms that the patient experiences, targeted and specific therapy is chosen to reduce the frequency and severity of migraine attacks. Specifically, the role of calcitonin gene-related peptide (CGRP) in the pathogenesis of migraine is analyzed, along with the drugs that effectively target the corresponding receptor. Particularly, CGRP receptor antagonists (gepants) are very effective drugs in the treatment of migraine, given their high diffusion in the brain. Moreover, following a ketogenic diet for only one or two months has been demonstrated to reduce migraine attacks. In this review, we highlight the diverse facets of migraine, from its physiopathological and pharmacological aspects to prevention and therapy.

Network pharmacology and experimental verification to explore the anti-migraine mechanism of Yufeng Ningxin Tablet

ETHNOPHARMACOLOGICAL RELEVANCE

Yufeng Ningxin Tablet (YNT) is a traditional Chinese medicine formula, that has been used clinically to treat migraine for many years. It is composed of one herb Pueraria lobata var. lobata (Willd.) Ohwi (Relevant Chinese name: Gegen). Previously, it has been recorded by traditional Chinese doctor that Gegen could be used as medicine to treat migraine. However, the underlying mechanism of action remains to be investigated.

AIM OF THE STUDY

It was to explore the effect and mechanism of YNT on migraine based on network pharmacology and experimental verification.

MATERIALS AND METHODS

First, with the network pharmacology, the effective chemical components and target genes of YNT were filtrated, the YNT-compound-migraine-targets network was constructed. The protein-protein interaction network (PPI) and literature reports were combined to identify potential targets of YNT in the treatment of migraine. Then, the representative compounds of YNT were characterized by LC-MS/MS and the major effect components were identified. Finally, the prediction results of network pharmacology were verified by animal and cell experiments.

RESULTS

7 bioactive components of YNT could act on 97 migraine potential targets. The 5 bioactive components could be characterized comprehensively of YNT. The key therapeutic targets and pathways were collected including 5-HT, CGRP, inflammation and nociceptive factors, and NF-κB signaling pathway. Animal experiments showed that YNT could increase the expression level of 5-HT and reduce the expression of CGRP, NF-κB, c-fos and IL-1β. YNT could inhibit LPS-induced neuroinflammation by NF-κB in BV2 cells in vitro. Western blotting analysis results showed YNT inhibited the NF-κB and phospho-NF-κB levels.

CONCLUSIONS

It is the first time to verify the consistency between the metabolic components of YNT by LC-MS/MS and the active components predicted by network pharmacology. Meanwhile, the potential mechanism of YNT in the treatment of migraine was studied by combining network pharmacology and in vitro and in vivo experiments.

Roxadustat alleviates nitroglycerin-induced migraine in mice by regulating HIF-1α/NF-κB/inflammation pathway

Sensitization of central pain and inflammatory pathways play essential roles in migraine, a primary neurobiological headache disorder. Since hypoxia-inducible factor-1α (HIF-1α) is implicated in neuroprotection and inflammation inhibition, herein we investigated the role of HIF-1α in migraine. A chronic migraine model was established in mice by repeated injection of nitroglycerin (10 mg/kg, i.p.) every other day for 5 total injections. In the prevention and acute experiments, roxadustat, a HIF-1α stabilizer, was orally administered starting before or after nitroglycerin injection, respectively. Pressure application measurement, and tail flick and light-aversive behaviour tests were performed to determine the pressure pain threshold, thermal nociceptive sensitivity and migraine-related light sensitivity. At the end of experiments, mouse serum samples and brain tissues were collected for analyses. We showed that roxadustat administration significantly attenuated nitroglycerin-induced basal hypersensitivity and acute hyperalgesia by improving central sensitization. Roxadustat administration also decreased inflammatory cytokine levels in serum and trigeminal nucleus caudalis (TNC) through NF-κB pathway. Consistent with the in vivo results showing that roxadustat inhibited microglia activation, roxadustat (2, 10, and 20 μM) dose-dependently reduced ROS generation and inflammation in LPS-stimulated BV-2 cells, a mouse microglia cell line, by inhibiting HIF-1α/NF-κB pathway. Taken together, this study demonstrates that roxadustat administration ameliorates migraine-like behaviours and inhibits central pain sensitization in nitroglycerin-injected mice, which is mainly mediated by HIF-1α/NF-κB/inflammation pathway, suggesting the potential of HIF-1α activators as therapeutics for migraine.

Pharmacological evaluation of carvacrol anti-migraine potential

Migraine is a devitalizing neurovascular disorder that affects millions of people worldwide. This study was directed against the determination of the effectiveness of carvacrol against migraine. In silico results revealed that carvacrol possesses specific scoring values of - 4.4 to - 6 against selected targets. In vivo studies showed that carvacrol (25-50 mg/Kg) decreased migraine pain by reversing thermal allodynia, mechanical allodynia, number of head-scratching, and light phobicity in rats. Levels of glutathione, glutathione-s-transferase, and catalase enhanced in the cortex and trigeminal nucleus caudalis of the animal's brain tissues, i.e., cortex and trigeminal nucleus caudalis with the use of carvacrol, while a significant decrease in lipid peroxide level was seen. Histopathological evaluation showed improvement in cellular architecture and a decrease in expression of certain inflammatory markers such as tumor necrosis factor-alpha, nuclear factor kappa B, interleukin-18, and prostaglandin E2 validated by enzyme-linked immune sorbent assay, immunohistochemistry, and western blot analysis. This study indicates that carvacrol exhibits binding affinities against different targets involved in migraine pathology and possesses anti-migraine action, mediated through anti-inflammatory and anti-oxidant pathways.

Effectiveness of gastrodin for migraine: A meta-analysis

Background

Gastrodia elata Blume (GEB), a traditional Chinese medicine, has been widely used to treat dizziness, numbness of limbs, and infantile convulsion, among other issues. Gastrodin is the main component of GEB. This meta-analysis aimed to evaluate the efficacy and safety of gastrodin in the treatment of migraine.

Methods

Ten electronic databases, namely the Cochrane Library, Embase, EBSCO, PubMed, Web of Science, CENTRAL, CNKI (China National Knowledge Infrastructure), CBM (Chinese Biomedicine Database), WanFang, and VIP (Chinese Scientific Journals Database), were searched for randomized controlled trials (RCTs) of gastrodin for migraine published before September 2021. The data were analyzed by RevMan 5.3 software and evaluated by GRADEpro.

Results

A total of 1,332 subjects were included in 16 RCTs. The meta-analysis showed that gastrodin was significantly effective in treating migraine (RR = 1.21, 95%CI = [1.17, 1.27]), reducing the pain degree (MD = −1.65, 95% CI = [−2.28, −1.02]), reducing the frequency of migraine attack (SMD = −2.77, 95% CI = [−3.92, −1.62]), shortening the duration of migraine attack (SMD = −1.64, 95% CI = [−2.35, −0.93]), and slowing average arterial cerebral blood flow velocity (SMD = −3.19, 95% CI = [−5.21, −1.17]), as well as being safe.

Conclusions

This systematic review revealed gastrodin is effective and safe in the treatment of migraine.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=197094, identifier: CRD42020197094.

Xiongshao Zhitong Recipe Attenuates Nitroglycerin-Induced Migraine-Like Behaviors via the Inhibition of Inflammation Mediated by Nitric Oxide Synthase

Migraine is a major cause of disability worldwide, particularly in young adults and middle-aged women. Xiongshao Zhitong Recipe (XZR) is a traditional Chinese medicine prescription used for treating migraine, but its bioactive components and therapeutic mechanisms remain unclear. We aimed to confirm the therapeutic effect of XZR on migraine and to determine the possible mechanism and bioactive components of XZR. Here, a sensitive UHPLC-LTQ-Orbitrap MS assay was carried out to analyze the ingredients of XZR, and a total of 62 components were identified, including coumarins, phenolic acids, phthalides, flavonoids, and terpenoids; among them, 15 components were identified in the serum samples after XZR treatment. We established a rat model of migraine via nitroglycerin (NTG) injection. The in vivo experiments demonstrated that XZR attenuated allodynia and photophobia in rats with NTG-induced migraine, and XZR also demonstrated analgesic effects. XZR reversed the abnormal levels of nitric oxide, 5-hydroxytryptamine (5-HT), calcitonin gene-related peptide (CGRP), and substance P (SP) to normal levels. XZR also downregulated inflammatory reactions, including mast cell degranulation and serum IL-1β, IL-6, and TNF-α levels. In terms of mechanism, we revealed that XZR treated NTG-induced migraine through the inhibition of neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS) expression in both the trigeminal nucleus caudalis (TNC) and periaqueductal gray matter (PAG), as well as the total NOS enzyme activity, which regulated the NF-κB signaling pathway. Additionally, imperatorin and xanthotoxin, two major ingredients of XZR, showed a high binding affinity to nNOS (Gly468-Leu616). In vitro, XZR, imperatorin, and xanthotoxin inhibited the nNOS expression and the NF-κB signaling pathway in lipopolysaccharide (LPS)-stimulated PC12 cells. In conclusion, we demonstrated the therapeutic effects of XZR and provided evidence that XZR played a critical anti-inflammatory role by suppressing NOS and NF-κB signaling pathway activation. Imperatorin and xanthotoxin were potential bioactive components of XZR. The findings from this study supported that XZR was a candidate herbal drug for migraine therapy.

IL-17 crosses the blood-brain barrier to trigger neuroinflammation: a novel mechanism in nitroglycerin-induced chronic migraine

Background

Chronic migraine places a disabling burden on patients, which is extensively modeled by the nitroglycerin (NTG)-treated animal model. Although the NF-κB pathway is involved in an increase in CGRP levels and activation of the trigeminal system in the NTG model, the relationship between NTG and neuroinflammation remains unclear. This study aimed to optimize a chronic NTG rat model with hyperalgesia and the ethological capacity for estimating migraine therapies and to further explore the underlying mechanism of NTG-induced migraine.

Methods

Rats were administered different doses of NTG s.c. daily or every 2 d; 30 min and 2 h later, the mechanical threshold was tested. After 9 d, the rats were injected with EB or Cy5.5 for the permeability assay. The other animals were sacrificed, and then, brainstem and caudal trigeminal ganglion were removed to test CGRP, c-Fos and NOS activity; Cytokines levels in the tissue and serum were measured by ELISA; and NF-κB pathway and blood–brain barrier (BBB)-related indicators were analyzed using western blotting. Immunohistochemistry was performed to observe microglial polarization and IL-17A⁺ T cell migration in the medulla oblongata.

Results

NTG (10 mg/kg, s.c., every 2 d for a total of 5 injections) was the optimal condition, resulting in progressive hyperalgesia and migraine behavior. TNC neuroinflammation with increases in cytokines, CGRP and c-Fos and activation of the NF-κB pathway was observed, and these changes were alleviated by ibuprofen. Furthermore, NTG administration increased BBB permeability by altering the levels functional proteins (RAGE, LRP1, AQP4 and MFSD2A) and structural proteins (ZO-1, Occludin and VE-cadherin-2) to increase peripheral IL-17A permeation into the medulla oblongata, activating microglia and neuroinflammation, and eventually causing hyperalgesia and migraine attack.

Conclusions

This study confirmed that NTG (10 mg/kg, s.c., every 2 d for a total of 5 injections) was the optimal condition to provoke migraine, resulting in mechanical hyperalgesia and observable migraine-like behavior. Furthermore, IL-17A crossed the blood–brain barrier into the medulla oblongata, triggering TNC activation through microglia-mediated neuroinflammation. This process was a novel mechanism in NTG-induced chronic migraine, suggesting that IL-17A might be a novel target in the treatment of migraine.

Study on the Chemical Constituents and Anti-Migraine Activity of Supercritical CO2 Extracts of Zanthoxylum schinifolium

Background:Zanthoxylum schinifolium is a common herbal medicine in Southwest China. It is also a condiment commonly used in many families. In Chinese folk medicine, Z. schinifolium is considered to have the effect of relieving migraine, but there is no modern evidence on its anti-migraine mechanism.

Objective: The aim of this study was to investigate the chemical constituents of the supercritical carbon dioxide extracts of Z. schinifolium (CO₂-ZSE) and its effects on migraine animals.

Materials and Methods: Supercritical CO₂ extraction technology was applied to extract the dried fruit of Z. schinifolium, and the chemical components were determined by gas chromatography–mass spectrometry (GC-MS). Two migraine animal models were established by subcutaneous injection of nitroglycerin (NTG) and reserpine, respectively, to further evaluate the therapeutic effect of CO₂-ZSE and explore its mechanism. On the basis of the experimental results, the therapeutic effects of linalool in different dosages and different ways of administration on NTG-induced migraine rats have been further investigated.

Results: About 125 peaks were detected in CO₂-ZSE, and the relative content of linalool was 74.16%. CO₂-ZSE decreased the number of head-scratching significantly and the levels of serum nitric oxide (NO), endothelin-1 (ET-1), calcitonin gene–related peptide (CGRP), interleukin-1β (IL-1β), nuclear factor kappa B (NF-κB) p65, and inhibitor of kappa B alpha (IκBα), and increased the level of 5-hydroxytryptamine (5-HT). Linalool has the potential to reduce the frequency of scratching the head and the expressions of NO, ET-1, and CGRP in NTG-induced migraine rats.

Conclusion: CO₂-ZSE has a definite therapeutic effect on migraine by affecting the expression of vasomotor factors and the inflammatory pathway. Linalool has been proven to be the main effective substance against migraine. These findings provide scientific basis for the development of effective and simple migraine therapy.

CGRP and CGRP-receptor as targets of migraine therapy: Brain Prize-2021

BACKGROUND

Migraine is a highly prevalent primary headache with an unclear pathomechanism. During the last 40 years numerous hypotheses have arisen, among them the theory of the trigeminovascular system is the primary one. It serves as a skeleton in successful preclinical studies and in the development of effective therapeutic options for migraine headache.

OBJECTIVE

The Brain Prize (awarded annually by the Lundbeck Foundation) is the most prestigious tribute in neuroscience. The winners in 2021 were Lars Edvinsson, Peter Goadsby, Michael Moskowitz and Jes Olesen. They are the fathers of the migraine pathomechanism which led to revolutionary new treatments. This review summarizes their landmark findings.

METHODS

Data related to this topic were reviewed from PubMed records published between 1979 and May 2021. Searches were based on preclinical and clinical studies in the covered field. The findings were listed in chronological order. From a therapeutic perspective, only randomized controlled trials and meta-analysis were discussed.

RESULTS

The calcitonin gene-related peptide-related pathogenesis of migraine is based on the activation of the trigeminovascular system. The therapeutic triad for migraine is triptans, gepants and calcitonin gene-related peptide-targeted monoclonal antibodies.

CONCLUSION

In the past 40 years, the systematic work of leading headache scientists has resulted in robust theoretical and therapeutic knowledge in the preclinical and clinical study of migraine.

VDR Gene Polymorphisms and Cluster Headache Susceptibility: Case-Control Study in a Southeastern European Caucasian Population

Cluster headache (CH) is a severe primary headache disorder with a genetic component, as indicated by family and twin studies. Diurnal and seasonal rhythmicity are key features of the disease and might be related to vitamin D, as low vitamin D levels have been observed in patients with cluster headache. In addition, the vitamin D receptor (VDR) occurs in brain areas and particularly in the hypothalamus. The aim of the present case-control study was to investigate the association of cluster headache susceptibility and clinical phenotypes with the VDR gene polymorphisms FokI, BsmI and TaqI in a Southeastern European Caucasian population. DNA was extracted from 131 unrelated CH patients and 282 non-headache controls and genotyped using real-time PCR (melting curve analysis). Linkage disequilibrium (LD) analysis confirmed that BsmI and TaqI, both located in the 3'UTR of the VDR gene, are in strong LD. Genotype and allele frequency distribution analysis of the VDR FokI, BsmI, and TaqI polymorphisms showed no statistically significant difference between cases and controls, whereas haplotype analysis indicated that the TAC haplotype might be associated with decreased cluster headache susceptibility. Intra-patient analysis according to diverse clinical phenotypes showed an association of the BsmI GG and TaqI TT genotypes with more frequent occurrence of CH attacks in this cohort. Therefore, a possible association was observed between VDR gene polymorphisms BsmI and TaqI or a linked locus and susceptibility for cluster headache development and altered clinical phenotypes in the Southeastern European Caucasian study population. Further large-scale replication studies are needed to validate these findings.

Targeting Glycogen Synthase Kinase 3 Beta Regulates CD47 Expression After Myocardial Infarction in Rats via the NF-κB Signaling Pathway

The aim of this study was to investigate the effects of the GSK-3β/NF-κB pathway on integrin-associated protein (CD47) expression after myocardial infarction (MI) in rats. An MI Sprague Dawley rat model was established by ligating the left anterior descending coronary artery. The rats were divided into three groups: Sham, MI, and SB + MI (SB216763) groups. Immunohistochemistry was used to observe the changes in cardiac morphology. A significant reduction in the sizes of fibrotic scars was observed in the SB + MI group compared to that in the MI group. SB216763 decreased the mRNA and protein expression of CD47 and NF-κB during MI. Primary rat cardiomyocytes (RCMs) and the H9c2 cell line were used to establish in vitro hypoxia models. Quantitative real-time PCR and western blotting analyses were conducted to detect mRNA and protein expression levels of CD47 and NF-κB and apoptosis-related proteins, respectively. Apoptosis of hypoxic cells was assessed using flow cytometry. SB216763 reduced the protein expression of CD47 and NF-κB in RCMs and H9c2 cells under hypoxic conditions for 12 h, and alleviated hypoxia-induced apoptosis. SN50 (an NF-κB inhibitor) also decreased CD47 protein expression in RCMs and H9c2 cells under hypoxic conditions for 12 h and protected cells from apoptosis. GSK-3β upregulates CD47 expression in cardiac tissues after MI by activating NF-κB, which in turn leads to myocardial cell damage and apoptosis.

Inflammatory Response Mechanisms of the Dentine-Pulp Complex and the Periapical Tissues

The macroscopic and microscopic anatomy of the oral cavity is complex and unique in the human body. Soft-tissue structures are in close interaction with mineralized bone, but also dentine, cementum and enamel of our teeth. These are exposed to intense mechanical and chemical stress as well as to dense microbiologic colonization. Teeth are susceptible to damage, most commonly to caries, where microorganisms from the oral cavity degrade the mineralized tissues of enamel and dentine and invade the soft connective tissue at the core, the dental pulp. However, the pulp is well-equipped to sense and fend off bacteria and their products and mounts various and intricate defense mechanisms. The front rank is formed by a layer of odontoblasts, which line the pulp chamber towards the dentine. These highly specialized cells not only form mineralized tissue but exert important functions as barrier cells. They recognize pathogens early in the process, secrete antibacterial compounds and neutralize bacterial toxins, initiate the immune response and alert other key players of the host defense. As bacteria get closer to the pulp, additional cell types of the pulp, including fibroblasts, stem and immune cells, but also vascular and neuronal networks, contribute with a variety of distinct defense mechanisms, and inflammatory response mechanisms are critical for tissue homeostasis. Still, without therapeutic intervention, a deep carious lesion may lead to tissue necrosis, which allows bacteria to populate the root canal system and invade the periradicular bone via the apical foramen at the root tip. The periodontal tissues and alveolar bone react to the insult with an inflammatory response, most commonly by the formation of an apical granuloma. Healing can occur after pathogen removal, which is achieved by disinfection and obturation of the pulp space by root canal treatment. This review highlights the various mechanisms of pathogen recognition and defense of dental pulp cells and periradicular tissues, explains the different cell types involved in the immune response and discusses the mechanisms of healing and repair, pointing out the close links between inflammation and regeneration as well as between inflammation and potential malignant transformation.

A Comprehensive Review on the Role of Genetic Factors in the Pathogenesis of Migraine

Migraine is a common neurovascular condition. This disorder has a complex genetic background. Several single-nucleotide polymorphisms (SNPs) or mutations within genes regulating glutamatergic neurotransmission, cortical excitability, ion channels, and solute carriers have been associated with polygenic and monogenic forms of migraine. SNPs within ACE, DBH, TRPM8, COMT, GABRQ, CALCA, TRPV1, and other genes have been reported to affect the risk of migraine or the associated clinical parameters. The distribution of some HLA alleles within the HLA-DRB1, HLA-DR2, HLA-B, and HLA-C regions have also been found to differ between migraineurs and healthy subjects. In addition, certain mitochondrial DNA changes and polymorphisms in this region have been shown to increase the risk of migraine. A few functional studies have investigated the molecular mechanisms contributing to these genetic factors in the development of migraine. Here we review studies evaluating the role of genetic polymorphisms and mRNA/miRNA dysregulation in migraine.

Nitric oxide role in anxiety-like behavior, memory and cognitive impairments in animal model of chronic migraine

The occurrence of cognitive dysfunctions and anxiety and mood disorders has been shown to be higher in migraine patients. Nitric Oxide (NO) is a significant neurotransmitter in the pathophysiology of migraine, anxiety and neurodegenerative disorders. Therefore, the present study was conducted to evaluate the role of NO system in migraine-induced memory impairment and anxiety like behaviors. Nitroglycerin (NTG) was administered to the animals as an animal model of migraine and pretreatment with L-Arginine, L-NAME and saline were implemented to evaluate the role of NO system in possible cognitive impairments in animal model of migraine. Avoidance learning and memory performance, object recognition memory, anxiety-like behavior and motor activity were assessed using a shuttle box apparatus, novel object recognition, elevated plus-maze, and open field tests respectively. The data showed that the injection of nitroglycerin disturbs learning and memory and elicit anxiety like behavior in the animals. L-NAME administration suppressed the observed effect of nitroglycerin on memory and anxiety. Overall, the results indicated that nitric oxide system is implicated in memory impairments and anxiety like behavior in an animal model of migraine.