Migraine, inflammatory bowel disease and celiac disease: a Mendelian randomization study

ObjectiveTo assess whether migraine may be genetically and/or causally associated with inflammatory bowel disease (IBD) or celiac disease.BackgroundMigraine has been linked to IBD and celiac disease in observational studies, but whether this link may be explained by a shared genetic basis or could be causal has not been established. The presence of a causal association could be clinically relevant, as treating one of these medical conditions might mitigate the symptoms of a causally linked condition.MethodsLinkage disequilibrium score regression and two-sample bidirectional Mendelian randomization analyses were performed using summary statistics from cohort-based genome-wide association studies of migraine (59,674 cases; 316,078 controls), IBD (25,042 cases; 34,915 controls) and celiac disease (11,812 or 4533 cases; 11,837 or 10,750 controls). Migraine with and without aura were analyzed separately, as were the two IBD subtypes Crohn's disease and ulcerative colitis. Positive control analyses and conventional Mendelian randomization sensitivity analyses were performed.ResultsMigraine was not genetically correlated with IBD or celiac disease. No evidence was observed for IBD (odds ratio [OR] 1.00, 95% confidence interval [CI] 0.99–1.02, p = 0.703) or celiac disease (OR 1.00, 95% CI 0.99–1.02, p = 0.912) causing migraine or migraine causing either IBD (OR 1.08, 95% CI 0.96–1.22, p = 0.181) or celiac disease (OR 1.08, 95% CI 0.79–1.48, p = 0.614) when all participants with migraine were analyzed jointly. There was some indication of a causal association between celiac disease and migraine with aura (OR 1.04, 95% CI 1.00–1.08, p = 0.045), between celiac disease and migraine without aura (OR 0.95, 95% CI 0.92–0.99, p = 0.006), as well as between migraine without aura and ulcerative colitis (OR 1.15, 95% CI 1.02–1.29, p = 0.025). However, the results were not significant after multiple testing correction.ConclusionsWe found no evidence of a shared genetic basis or of a causal association between migraine and either IBD or celiac disease, although we obtained some indications of causal associations with migraine subtypes.Genetics of disease, diagnosis and treatmen

Both Early and Delayed Treatment with Melanocortin 4 Receptor-Stimulating Melanocortins Produces Neuroprotection in Cerebral Ischemia

Ischemic stroke is one of the main causes of death and disability. We investigated whether melanocortin peptides, which have protective effects in severe hypoxic conditions, also produce neuroprotection in a gerbil model of ischemic stroke. A 10-min period of global cerebral ischemia, induced by occluding both common carotid arteries, caused impairment in spatial learning and memory that was associated with activation of inflammatory and apoptotic pathways, including severe DNA damage and delayed neuronal death, in the hippocampus. Treatment with nanomolar doses of the melanocortin analog [Nle4, D-Phe7] {alpha}-MSH [which activates the melanocortin receptor subtypes (MC) mainly expressed in central nervous system, namely MC3 and MC4] modulated the inflammatory and apoptotic cascades and reduced hippocampus injuries even when delayed up to 9 h after ischemia, with consequent dose-dependent improvement in subsequent functional recovery. The selective MC3 receptor agonist {gamma}2-MSH had no protective effects. Pharmacological blockade of MC4 receptors prevented the neuroprotective effects of [Nle4, D-Phe7] {alpha}-MSH and worsened some ischemia outcomes. Together, our findings suggest that MC4 receptor-stimulating melanocortins might provide potential to develop a class of drugs with a broad treatment window for a novel approach to neuroprotection in ischemic stroke