[Show abstract][Hide abstract] ABSTRACT: The association between the clinical use of nitroglycerin (NTG) and migraine suggests NTG as an animal model trigger for migraine. NTG-induced hyperalgesia in rats has been extensively used as a migraine model for pre-clinical research. Pregabalin is an anti-epileptic drug and may play a role in the preventive treatment of migraine; however, the mechanism of this action remains to be clarified. Herein, we performed the present study to investigate the effect of pregabalin on the NTG-induced hyperalgesia in rats. Sixty male Sprague-Dawley rats were divided equally into six groups. Thirty minutes before NTG injection, the rats were pretreated with pregabalin. von Frey hair testing was employed to evaluate tactile sensitivity. Enzyme linked immunosorbent assay was used to analyze plasma calcitonin gene-related peptide (CGRP) level in the jugular vein. Immunohistochemistry was applied to detect c-Fos immunoreactive neurons and western blot was performed to detect c-Fos protein expression in trigeminal nucleus caudalis (TNC). We found that pregabalin pretreatment alleviated the NTG-induced hyperalgesia. Moreover, pregabalin suppressed peripheral CGRP release, c-Fos immunoreactive neurons and the protein expression of c-Fos in TNC as well. These data suggest that pregabalin could alleviate the NTG-induced hyperalgesia. Further studies are required to determine the mechanisms of action for this effect.
[Show abstract][Hide abstract] ABSTRACT: This study was designed to investigate whether telomerase was involved in the neuroprotective effect of curcumin and Cur1. Alzheimer's disease is a consequence of an imbalance between the generation and clearance of amyloid-beta peptide in the brain. In this study, we used Aβ1-42 (10 µg/ml) to establish a damaged cell model, and curcumin and Cur1 were used in treatment groups. We measured cell survival and cell growth, intracellular oxidative stress and hTERT expression. After RNA interference, the effects of curcumin and Cur1 on cells were verified. Exposure to Aβ1-42 resulted in significant oxidative stress and cell toxicity, and the expression of hTERT was significantly decreased. Curcumin and Cur1 both protected SK-N-SH cells from Aβ1-42 and up-regulated the expression of hTERT. Furthermore, Cur1 demonstrated stronger protective effects than curcumin. However, when telomerase was inhibited by TERT siRNA, the neuroprotection by curcumin and Cur1 were ceased. Our study indicated that the neuroprotective effects of curcumin and Cur1 depend on telomerase, and thus telomerase may be a target for therapeutic effects of curcumin and Cur1.
[Show abstract][Hide abstract] ABSTRACT: Analgesic overuse often happens to migraine patients, especially chronic migraineurs, and migraine has been demonstrated to be associated with white matter lesions (WMLs). The aim of this study was to investigate the relationship between medication overuse headache (MOH) and WMLs in chronic migraine (CM) patients. Subjects were enrolled and divided into three groups: healthy controls, CM without MOH (CMwoMOH), and CM with MOH (CM-MOH). Most of the CM patients used non-steroidal anti-inflammatory drugs (NSAIDs) as acute headache medications. All the participants underwent magnetic resonance imaging scans and images were obtained for WML evaluation with semiquantitative scales. One hundred and forty-one participants were included, 45 of them for controls, 38 for CMwoMOH, and 58 for CM-MOH. In women, CMwoMOH patients had a higher prevalence of high WML load compared with controls and CM-MOH patients. In men, however, all the study groups showed no differences in the prevalence of high WML load. CMwoMOH women had increased risks of high deep white matter lesion (DWML) load compared with controls, while they had no risks of high periventricular white matter lesion (PVWML) load. CM-MOH women had no risks of high DWML load, but they had reduced risks of high PVWML load. The association of CM-MOH with high WML load in women was not changed when compared with CMwoMOH. Age was independently associated with high WML load among women. These data suggest that MOH caused by NSAIDs is not a risk factor for WMLs. Rather, NSAID overuse probably protects MOH patients from WMLs through anti-inflammatory effects.
No preview · Article · Feb 2014 · Journal of Neurology
[Show abstract][Hide abstract] ABSTRACT: To investigate the patient satisfaction with medications commonly used for migraine therapy in patients seen in headache clinic in China with emphasis on the evaluation of Chinese patent medicine (CPM) in relieving acute migraine attack.
Patients admitted at headache clinics in the neurological departments of four hospitals during April to October 2011 were enrolled in the investigation. The questionnaire was designed based on the validation of a diagnostic questionnaire for a population-based survey in China in 2009.
Among 219 eligible patients, 58% had used CPM at the acute attack of migraine while the guideline-recommended treatments were seldom used. However, patients using CPMs were less satisfied than those using Western Medicines (WMs) in either single medication groups or mixed medication groups (P < 0.05).
Fifty-eight percent of the eligible respondents in Guangdong and Guangxi Province had used CPM at the acute attack of migraine, but based on our data, the effect of CPM on treating migraine attack was poor with low satisfaction compared with WMs. However, many factors may bias or explain our findings. This suggests the need for accelerated research in understanding patient choice, treatment availability, and use of medications.
[Show abstract][Hide abstract] ABSTRACT: Pleiotrophin (PTN) is an effective neuroprotective factor and its expression is strikingly increased in microglia after ischemia/reperfusion injury. However, whether PTN could provide neurotrophic support to neurons by regulating microglia function is not clear. In this study, we demonstrated that the expression of PTN was induced in microglia after oxygen-glucose deprivation/reperfusion. PTN promoted the proliferation of microglia by enhancing the G1 to S phase transition. PTN also stimulated the secretion of brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF) and nerve growth factor (NGF) in microglia, but did not upregulate the expression of proinflammatory factors such as TNF-α, IL-1β and iNOS. Mechanistically, we found that PTN increased the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 in microglia in both concentration-dependent and time-dependent manners. In addition, ERK1/2 inhibitor U0126 abolished the proliferation and G1 to S phase transition of microglia stimulated by PTN, and inhibited the production of BDNF, CNTF and NGF induced by PTN. In conclusion, our results demonstrated that PTN-ERK1/2 pathway plays important role in regulating microglia growth and secretion of neurotrophic factors. These findings provide new insight into the neuroprotective role of PTN and suggest that PTN is a new target for therapeutic intervention of stroke.
No preview · Article · Dec 2012 · Neuroscience Research
[Show abstract][Hide abstract] ABSTRACT: Overuse of analgesic plays a prominent role in migraine chronification. Paracetamol caffeine aspirin (PCA) powders are commonly used in Chinese migraineurs. This study investigated the effects of the specific combination analgesic on cerebral glucose metabolism in chronic migraine (CM).
18F-FDG-PET was used to measure regional metabolism in all subjects. Brain metabolisms of CM patients with analgesic overuse (AO-CM; n = 10), no analgesic overuse (NAO-CM; n = 10), and no regimen (NR-CM; n = 10) and 17 age- and gender-matched normal controls (NC) were compared using statistical parametric mapping. Then, all patients underwent brain MRI analysis within 7 days after PET scans, as well as MMSE and MoCA scale for cognitive function tests.
Glucose metabolic changes in CM patients taking different dosage of analgesic during headache-free periods and clear distinctions in several brain regions were observed. Patients with AO-CM exhibited significant metabolic reductions in thalamus, as well as increased metabolism in middle temporal gyrus and insula relative to NR-CM and NAO-CM. However, in these regions, no difference was observed in AO-CM except for increased metabolism in the right insula relative to NC group.
Overusing PCA powders affects regional brain glucose metabolism in CM. Increased metabolism in the right insula may be associated with recurrently overusing of PCA powders.
No preview · Article · Oct 2012 · European Journal of Neurology
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to investigate the effects of transcranial direct current stimulation (TDCS) on hemichannel pannexin-1 (PX1) in cortical neurons and neural plasticity, and explore the optimal time window of TDCS therapy after stroke. Adult male Sprague–Dawley rats (n = 90) were randomly assigned to sham operation, middle cerebral artery occlusion (MCAO), and TDCS groups, and underwent sham operation, unilateral middle cerebral artery (MCA) electrocoagulation, and unilateral MCA electrocoagulation plus TDCS (daily anodal and cathodal 10 Hz, 0.1 mA TDCS for 30 min beginning day 1 after stroke), respectively. Motor function was assessed using the beam walking test (BWT), and density of dendritic spines (DS) and PX1 mRNA expression were compared among groups on days 3, 7, and 14 after stroke. Effects of PX1 blockage on DS in hippocampal neurons after hypoxia–ischemia were observed. TDCS significantly improved motor function on days 7 and 14 after stroke as indicated by reduced BWT scores compared with the MCAO group. The density of DS was decreased after stroke; the TDCS group had increased DS density compared with the MCAO group on days 3, 7, and 14 (all P < 0.0001). Cerebral infarction induced increased PX1 mRNA expression on days 3, 7, and 14 (P < 0.0001), and the peak PX1 mRNA expression was observed on day 7. TDCS did not decrease the up-regulated PX1 mRNA expression after stroke on day 3, but did reduce the increased post-stroke PX1 mRNA expression on days 7 and 14 (P < 0.0001). TDCS increased the DS density after stroke, indicating that it may promote neural plasticity after stroke. TDCS intervention from day 7 to day 14 after stroke demonstrated motor function improvement and can down-regulate the elevated PX1 mRNA expression after stroke.
[Show abstract][Hide abstract] ABSTRACT: The objective of this study was to observe the efficacy, safety, and side effects of a combination of flunarizine plus topiramate compared with either flunarizine and or toparamate alone for migraine prophylaxis.
Out of 150 patients with migraine recruited into the study and randomly assigned to one of three conditions, 126 completed the trial in their group: flunarizine (39), topiramate (44), and flunarizine plus topiramate (43). Patient information was assessed at enrollment and at follow-up visits at the end of months 1-3, 6, 9, and 12. The primary measure of efficacy reduction in mean monthly migraine frequency of at least 50% as compared with baseline. Secondary efficacy parameters included reduction in mean monthly migraine days and severity of headache. Side effects were compared in the three groups by recording adverse reactions and weight changes.
The proportion whose monthly headache frequency decreased more than 50% was 66.7% (26/39) in the flunarizine group, 72.7% (32/44) in the topiramate group and 76.7% (33/43) in the combination group, respectively (P=0.593). The mean monthly days and severity of headache in the three groups also declined and was more significant in the flunarizine plus topiramate group than in the flunarizine group and the topiramate group (P<0.05). In the flunarizine group, the average weight change was 0.6kg. Topiramate was associated with a mean weight loss was of -0.9kg in the topiramate group and -0.2kg in the flunarizine plus topiramate group.
Flunarizine, topiramate, and the combination of flunarizine with topiramate are all effective and have good tolerability in migraine prophylaxis. Adding topiramate to flunarizine may reduce the latter's impact on body weight.