The Link Between Pain Patient and Analgesic Medication is Greater in Migraine than in Rheumatic Disease Patients

Our aim was to measure and compare the link between pain patients and the different kinds of analgesic medications they use by the Leeds Dependence Questionnaire (LDQ). This is a self-completion 10-item instrument to measure the severity of dependence upon a variety of substances. LDQ was administered to 200 episodic migraine patients (EM group), 77 chronic migraine patients (CM group) overusing acute medications, and 114 patients suffering from rheumatic disease (RD group), consecutively attending the Headache Centre or the Rheumatology Clinic of the University Hospital of Modena in the course of the first semester of 2007. The link with analgesics was greater in migraine patients than in patients with rheumatic disease, since the LDQ total score was significantly higher in the EM (6.65 ± 0.32, P < 0.005) and CM groups (9.61 ± 0.59, P < 0.0001) than in the RD group (5.17 ± 0.37) (Kruskal–Wallis and Mann–Whitney U-tests). Migraine patients were significantly more linked to triptans and to combined medications than to non-steroidal anti-inflammatory drugs. The strength of the link between migraine patients and the analgesic medications they take could represent a factor of vulnerability: overusing these medications could develop medication overuse headache.

Effective prophylactic treatments of migraine lower plasma glutamate levels

The role of glutamate in migraine treatment has not been much studied, even if this amino acid seems to be crucial in the pathogenesis of migraine. Our aim was to determine if there were differences in the plasma levels of glutamate between migraine patients and control subjects and if plasma levels of glutamate in migraine patients modified after 8 weeks of prophylactic treatment. We studied 24 patients with diagnosis of migraine without aura according to International Classification of Headache Disorders, 2nd edn criteria, and 24 age- and sex-matched healthy subjects, as controls. In migraineurs the level of glutamate was measured before and after 8 weeks of prophylactic treatment (topiramate 50 mg/day, five patients; amitriptyline 20 mg/day, seven patients; flunarizine 5 mg/day, seven patients; propranolol 80 mg/day, five patients). Venous blood samples were taken in the morning, after overnight fasting, and at least 3 days after the last migraine day. Glutamate levels were measured by means of a fluorimetric detector high-pressure liquid chromatographic method. Plasma levels of glutamate were significantly higher in migraine patients-either before (61.79 +/- 18.75 micromol/l) or after prophylactic treatment (17.64 +/- 5.08 micromol/l)-than in controls (9.36 +/- 2.1 micromol/l) (P < 0.05, anova followed by Newman-Keuls' test). After prophylactic treatment, with headache frequency reduced, plasma glutamate levels were significantly lower in the same patient with respect to the prior baseline level (P < 0.0001, Student's t-test for paired data), without any differences depending on the kind of prophylactic drug. Effective prophylactic treatments reducing high glutamate plasma levels found in migraine patients could act on the underlying mechanism that contributes to cause migraine. Plasma glutamate level monitoring in migraine patients might serve as a biomarker of response to treatments and as an objective measure of disease status.

Targeting the central nervous system: In vivo experiments with peptide-derivatized nanoparticles loaded with Loperamide and Rhodamine-123

Polymeric nanoparticles (Np) represent one of the most innovative non-invasive approaches for the drug delivery to the central nervous system (CNS). It is known that the ability of the Np to cross the Blood Brain Barrier (BBB), thus allowing the drugs to exert their pharmacological activity in the central nervous district, is linked to their surface characteristics. Recently it was shown that the biocompatible polyester poly(d,l-lactide-co-glycolide) (PLGA) derivatized with the peptide H(2)N-Gly-l-Phe-d-Thr-Gly-l-Phe-l-Leu-l-Ser(O-beta-d-Glucose)-CONH(2) [g7] was a useful starting material for the preparation of Np (g7-Np); moreover, fluorescent studies showed that these Np were able to cross the BBB. In this research, g-7 Np were loaded with Loperamide in order to assess their ability as drug carriers for CNS, and with Rhodamine-123, in order to qualitatively determine their biodistribution in different brain macro-areas. A pharmacological evidence is given that g7-Np are able to cross the BBB, ensuring, for the first time, a sustained release of the embedded drug, and that these Np are able to reach all the brain areas here examined. The ability to enter the CNS appears to be linked to the sequence of the peptidic moiety present on their surface.