Neurochemical metabolite alterations of the occipital lobe in migraine without aura by proton magnetic resonance spectroscopy

BACKGROUND

Migraine without aura is the most common type of migraine headache, accounting for about 80% of all migraines. The aim of the present investigation was to determine the neurochemical metabolite alterations in the occipital lobe of patients suffering from migraine without aura using proton magnetic resonance spectroscopy (1H-MRS).

METHODS

Fifteen patients suffering from migraine without aura with an occipital plaque and 16 healthy controls were included in this study. Changes in the neurochemical metabolites in the occipital lobe were assessed using 1H-MRS. The ratios of N-acetylaspartate (NAA) to creatine (Cr), choline (Cho) to Cr and myo-inositol (MI) to NAA were measured by voxel volume at 8 cm3.

RESULTS

The mean NAA/Cr ratio decreased significantly in patients compared to controls. Cho/Cr and MI/NAA ratios increased significantly in patients. In addition, the duration of the disease and the frequency of headache attacks were significantly associated with a decrease in the NAA/Cr ratio and an increase in the Cho/Cr ratio.

CONCLUSIONS

Migraine without aura shows a significant association with changes in neurochemical metabolites detectable by 1H-MRS in the occipital lobe of patients. In addition, changes in metabolic ratios showed a significant relationship with the duration of the disease and the frequency of headache attacks.

[Calcium homeostasis and nitric oxide processes in children with migraine]

Eighty-one children aged 6 to 17 years who had migraine were examined by clinical and biochemical studies. The activity of Ca2(+)-ATPase and the levels of total intracellular calcium of platelets and plasma nitrites were studied in the attack-free period. Children with migraine were fond to have elevated levels of stable nitric oxide metabolites (nitrites). The level of intracellular calcium was 2 times greater than that in healthy children of the same age, which was followed by compensatory Ca2(+)-ATPase activation. There was a relationship of the parameters of calcium homeostasis and the plasma level of nitrites to the clinical and pathogenetic manifestations of migraine.

Oxidative stress in migraine with and without aura

Migraine is the most common neurological disorder, but the molecular basis is still not completely understood. An impairment of mitochondrial oxidative metabolism might play a role in the pathophysiology. The goal of this study was to investigate the differences in oxidative stress status with the measurement of erythrocyte superoxide dismutase (SOD), catalase activity, and malondialdehyde (MDA) levels in the migraine patients with or without aura and attack. There were 56 patients (46 female, 10 male) in the migraine group and 25 matched healthy subjects in the control group. The patients comprised 37 with migraine without aura (MWoA], 19 with migraine with aura (MWA), and 22 with headache attack. The MDA levels of patients in the migraine group were significantly higher than that in the control group. The SOD activity was significantly higher in the MWA as compared to MWoA. There was no significant correlation between these levels and headache attack period. Conclusively, in this preliminary study, we had found increased oxidative stress in the migraine patients especially the patients with MWA. Further knowledge about this issue may contribute the cause and complications of migraine and may be essential for development of treatment approaches.

Functional 1H-MRS findings in migraine patients with and without aura assessed interictally

The present study was aimed at investigating changes in brain metabolites due to visual cortex activation in migraineurs and normal subjects by (1)H-magnetic resonance spectroscopy (MRS). Twenty-two migraine patients with aura, 22 migraine patients without aura, and 10 control subjects were assessed. The volume of interest (about 8 cm(3)) was placed on the visual cortex area and the visual stimulus was applied using MR-compatible goggles with a flashing red light at a frequency of 8 Hz and an intensity of 14 lx. Data were acquired over 36'40". The experimental time course was: baseline phase, from 0 to 3'40" (1 spectrum); on phase (flashing light condition), from 3'40" to 29'20" (1540") (7 spectra), and off phase, from 29'20" to the end of the experiment at 36'40" (2 spectra). The main result of photic stimulation in patients with migraine with aura is the more consistent decrease (-14.61%) of the N-acetylaspartate (NAA) signal, which is significantly greater than that found in migraine patients without aura and control subjects. A parallel slight increase in the lactate peak was also detected. The above findings support little differences in brain metabolites between the two patient groups assessed in interictal periods, which suggests a less efficient mitochondrial functioning in migraine with aura patients.

[Suppressing effect of the serotonin 5HT1B/D receptor agonist rizatriptan on calcitonin gene-related peptide (CGRP) concentration in migraine attacks]

Calcitonin gene-related peptide (CGRP) is one of the neuropeptides most abundant in the nervous tissue. Recent studies indicate that local cranial release of CGRP from the trigeminal nerve perivascular endings within arachnoidea plays an important role in the pathophysiology of migraine attacks and cluster headaches. Elevated CGRP levels in cranial venous blood (in the jugular vein) during an acute spontaneous migraine attack have been reported in rather few studies so far. Sumatriptan--a selective serotonin 5HT1B/D receptor agonist, highly effective in terminating migraine attacks, decreases the elevated CGRP level back to normal. The aim of our study was to determine the effect of rizatriptan (a drug from a new generation of triptans) on CGRP release in migraine attacks. In 45 patients suffering from migraine attacks with and without aura, plasma CGRP levels were assessed during an attack twice: before treatment and two hours after rizatriptan administration. In the group under study the plasma CGRP level before treatment was significantly higher than that measured two hours after rizatriptan administration. The decrease in CGRP levels was associated with subsidence of the migraine attack. There was no difference between migraine patients with and without aura. These results suggest that triptans as serotonin 5HT1B/D receptor agonists decrease CGRP plasma concentration in migraine attacks.

Contrasts in cortical magnesium, phospholipid and energy metabolism between migraine syndromes

BACKGROUND

Previous single voxel (31)P MRS pilot studies of migraine patients have suggested that disordered energy metabolism or Mg(2+) deficiencies may be responsible for hyperexcitability of neuronal tissue in migraine patients. These studies were extended to include multiple brain regions and larger numbers of patients by multislice (31)P MR spectroscopic imaging.

METHODS

Migraine with aura (MWA), migraine without aura (MwoA), and hemiplegic migraine patients were studied between attacks by (31)P MRS imaging using a 3-T scanner.

RESULTS

Results were compared with those in healthy control subjects without headache. In MwoA, consistent increases in phosphodiester concentration [PDE] were measured in most brain regions, with a trend toward increase in [Mg(2+)] in posterior brain. In MWA, phosphocreatine concentration ([PCr]) was decreased to a minor degree in anterior brain regions and a trend toward decreased [Mg(2+)] was observed in posterior slice 1, but no consistent changes were found in phosphomonoester concentration [PME], [PDE], inorganic phosphate concentration ([Pi]), or pH. In hemiplegic migraine patients, [PCr] had a tendency to be lower, and [Mg(2+)] was significantly lower than in the posterior brain regions of control subjects. Trend analysis showed a significant decrease of brain [Mg(2+)] and [PDE] in posterior brain regions with increasing severity of neurologic symptoms.

CONCLUSIONS

Overall, the results support no substantial or consistent abnormalities of energy metabolism, but it is hypothesized that disturbances in magnesium ion homeostasis may contribute to brain cortex hyperexcitability and the pathogenesis of migraine syndromes associated with neurologic symptoms. In contrast, migraine patients without a neurologic aura may exhibit compensatory changes in [Mg(2+)] and membrane phospholipids that counteract cortical excitability.

Serum ionized magnesium levels and serum ionized calcium/ionized magnesium ratios in women with menstrual migraine

OBJECTIVE

It has been suggested that magnesium deficiency may play an important role in menstrual migraine and that the serum ionized calcium (ICa2+)/ionized magnesium (IMg2+) ratio is important in migraine headache. Studies were designed to test these hypotheses.

DESIGN

We prospectively evaluated 270 women seen at a headache clinic and in 61 women with menstrual migraine measured IMg2+, total magnesium, and ICa2+ levels so as to calculate the ICa2+/IMg2+ ratio.

RESULTS

The incidences of IMg2+ deficiency were 45% during menstrual attacks, 15% during nonmenstrual attacks, 14% during menstruation without a migraine, and 15% between menstruations and between migraine attacks. The serum ICa2+ levels were within our reference range, but the ICa2+/IMg2+ ratio was elevated (P<.01) in menstrual migraine.

CONCLUSIONS

The high incidence of IMg2+ deficiency and the elevated ICa2+/IMg2+ ratio during menstrual migraine confirm previous suggestions of a possible role for magnesium deficiency in the development of menstrual migraine.

[Molecular genetic findings in migraine]

This review focuses on the different molecular genetic findings in migraine. Familial hemiplegic migraine (FHM) is a rare subtype of migraine with aura, which is inherited as an autosomal dominant. Half the cases of FHM are caused by point mutations in the CACNA1A gene on the short arm of chromosome 19 (19p). The gene encodes a calcium ion channel. Other mutation types cause episodic ataxia 2 (EA-2). Expansions of the CAG repeat in the 3' end bring about spinocerebellar ataxia 6 (SCA 6). Some families with FHM link to loci on the long arm of chromosome 1 (1q). The genes have not yet been identified. Some families neither link to 1q nor to 19p. Population-based family and twin studies have shown that migraine both with and without aura have a multifactorial inheritance. The CACNA1A gene may be of importance for ordinary forms of migraine in a few families. Mutations in genes on the X chromosome, dopamine receptor genes, and the ACE gene appear to be involved in migraine in a few families, whereas genes for nitric oxide synthase, serotonin receptors, and mitochondrial DNA do not seem to be involved. The positive associations have not been reproduced in other studies and therefore they should be interpreted with care. It is to be hoped that in the next few years much more will be known about the molecular genetic mechanisms of migraine with and without aura. FHM is an ion channel disorder, and many factors suggest that migraine is also an ion channel disorder, which is consistent with the paroxysmal nature of the illness.

Course of primary headaches during hormone replacement therapy

OBJECTIVE

The aim of the present study was to evaluate how hormone replacement therapy (HRT) could influence the course of primary headaches in postmenopausal women.

METHODS

Fifty patients presenting for clinical evaluation of menopausal status and suffering from headache were enrolled. The observational period lasted 7 months during which women filled in a diary with the clinical characteristics of headache attacks (frequency, days with headache, severity) and the analgesic use (no. of analgesic/month). Climacteric symptoms and both anxiety and depression were also measured. At the first visit the patients were divided into two groups: those suffering from migraine without aura (MwA) and those suffering from episodic tension-type headache (ETTH) and separately randomized. After a month of run-in period, they received two different HRT regimen, either: (1) transdermal estradiol 50 mcg every 7 days for 28 days plus medroxyprogesterone acetate (MAP) 10 mg/day from 15th to 28th day, or (2) oral conjugated estrogens 0.625 mg/day for 28 days plus MAP 10 mg/day for the last 14 days. Follow up evaluations were planned after 1, 3 and 6 months of treatment.

RESULTS

While we did not observe any significance change regarding headache parameters in ETTH patients during both transdermal and oral treatment, the course of migraine was significantly affected by the route of HRT. Both frequency of attacks (F = 8.5; P < 0.000) and days with headache (F = 6.9; P < 0.000) significantly increased during HRT in the subgroup assuming oral formulation. On the contrary, no changes in the same parameters were found in the group taking transdermal treatment. Moreover, while severity of migraine was unaffected by HRT, analgesic consumption was significantly increased in the subgroup on oral treatment (F = 6.3; P = 0.001).

CONCLUSIONS

HRT significantly affects the course of headache in postmenopausal migraine sufferers. Indeed, while the clinical pattern of ETTH remained stable throughout the observational period, patients suffering from MwA worsened their symptoms within the first 3 months of treatment. In particular, the oral route of administration significantly worsened migraine in comparison to the transdermal route.

Linked activation of nitric oxide synthase and cyclooxygenase in peripheral monocytes of asymptomatic migraine without aura patients

Many reports indicate that nitric oxide (NO) could be involved in migraine without aura (MWA), an extremely diffuse clinical event. Since monocyte may be a relevant source of NO, we analysed monocyte activation in MWA patients, in a period in which they were free of symptoms. NO basal production by MWA peripheral monocytes was significantly higher than in healthy subjects (91.25+/-8.6 microM/10(6) cells vs. 22.6+/-3.2 microM/106 cells). Interestingly, even the release of prostaglandin E2 (PGE2), was higher in MWA patients than in healthy subjects (3137+/-320 pg/10(6) cells vs. 1531+/-220 pg/10(6) cells). The incubation of monocytes from healthy subjects and MWA patients with N-nitro-L-arginine methyl ester caused a marked decrease of both NO and PGE2 release. We hypothesise that NOS and cyclooxygenase pathways in monocytes are linked and are, in MWA patients, up-regulated, even in a symptoms-free period. NO and PGE2 hyperproduction could therefore be involved in the neurovascular modifications leading to migraine attacks.

Effects of the anti-migraine drug sumatriptan on muscle energy metabolism: relationship to side-effects

Sumatriptan succinate (Imitrex) is a 5-HT (5-hydroxytryptamine) agonist used for relief of migraine symptoms. Some individuals experience short-lived side-effects, including heaviness of the limbs, chest heaviness and muscle aches and pains. The effects of this drug on skeletal muscle energy metabolism were studied during short submaximal isometric exercises. We studied ATP flux from anaerobic glycolysis (An Gly), the creatine kinase reaction (CK) and oxidative phosphorylation (Ox Phos) using 31P nuclear magnetic resonance spectroscopy (31P MRS) kinetic data collected during exercise. It was found that side-effects induced acutely by injection of 6 mg sumatriptan succinate s.c. were associated with reduced oxygen storage in peripheral skeletal muscle 5-20 min after injection as demonstrated by a transient reduction in mitochondrial function at end-exercise. These results suggest that mild vasoconstriction in peripheral skeletal muscle is associated with the action of sumatriptan and is likely to be the source of the side-effects experienced by some users. Migraine with aura patients were more susceptible to this effect than migraine without aura patients.

Glyceryl trinitrate induces attacks of migraine without aura in sufferers of migraine with aura

Migraine with aura and migraine without aura have the same pain phase, thus indicating that migraine with aura and migraine without aura share a common pathway of nociception. In recent years, increasing evidence has suggested that the messenger molecule nitric oxide (NO) is involved in pain mechanisms of migraine without aura. In order to clarify whether the same is true for migraine with aura, in the present study we examined the headache response to intravenous infusion of glyceryl trinitrate (GTN) (0.5 microg/kg/min for 20 min) in 12 sufferers of migraine with aura. The specific aim was to elucidate whether an aura and/or an attack of migraine without aura could be induced. Fourteen healthy subjects served as controls. Aura symptoms were not elicited in any subject. Headache was more severe in migraineurs than in the controls during and immediately after GTN infusion (p=0.037) as well as during the following 11 h (p = 0.008). In the controls, the GTN-induced headache gradually disappeared, whereas in migraineurs peak headache intensity occurred at a mean time of 240 min post-infusion. At this time the induced headache in 6 of 12 migraineurs fulfilled the diagnostic criteria for migraine without aura of the International Headache Society. The results therefore suggest that NO is involved in the pain mechanisms of migraine with aura. Since cortical spreading depression has been shown to liberate NO in animals, this finding may help our understanding of the coupling between cortical spreading depression and headache in migraine with aura.