Knowing Molecular Factors involved in Migraine
Migraine is usually a moderate or severe headache felt as a throbbing pain on one side of the head. The most common symptoms of a migraine attack include throbbing headache, sensitivity to light and noise, nausea (feeling sick), vomiting (being sick) and lethargy (lack of energy). It is a common neurological disorder that affects 11% of adults worldwide and most likely has neurovascular origin.
Migraine with aura and more common form- migraine without aura are the two main subtypes of disease. The exact pathology of migraine is still unknown, but both genetic and environmental factors are thought to be involved. Various studies have been conducted for gene analysis involved in migraine.
The genetic studies of migraine were focused on the rare sub type of migraine attack: familial hemiplegic migraine (FHM). The genes analyzed in familial and sporadic migraine were MTHFR, KCNK 18, HCRTR1, SLC6A4, STX1A, GRIA1 and GRIA3. Possibilities observed were that migraine was a multi-factorial disease with polygenic influence. Recent studies have also shown that the pathology of migraine involved both factors responsible for immune response and oxidative stress such as: cytokines, tyrosine metabolism, homocysteine and factors associated with pain transmission and emotions. e.g. serotonin, hypocretin-1, calcitonin gene-related peptide, glutamate.
After observations, the correlations between genetic variants of HCRTR1 gene, polymorphism 5-HTTLPR and hypocretin-1 and serotonin were noted. It was concluded that serotonin inhibits the activity of hypocretin neurons and might affect the appearance of the aura during migraine attack. The understanding of molecular mechanisms of migraine included genotype-phenotype correlations might have contributed to the finding markers which were important for the diagnosis and treatment of the disease. Such biomarkers could be detected in the blood or saliva sample of individuals using biochemical or molecular methods and would be helpful in migraine diagnosis. This might also help in monitoring drug response, disease prognosis and/or progression.
However, some of the mentioned molecular factors are still under investigation as new targets for migraine pharmacotherapy. Moreover, the neuropeptides and their receptors might be used for future treatment and prophylaxis of migraine.