Molecular Mechanisms of Curcumin in Neuroinflammatory Disorders: A Mini Review of Current Evidences.

OBJECTIVE: Neuroinflammatory disease is a general term used to denote the progressive loss of neuronal function or structure. Many neuroinflammatory diseases, including Alzheimer's, Parkinson's, and multiple sclerosis (MS), occur due to neuroinflammation. Neuroinflammation increases nuclear factor-κB (NF-κB) levels, cyclooxygenase-2 enzymes and inducible nitric oxide synthase, resulting in the release of inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α). It could also lead to cellular deterioration and symptoms of neuroinflammatory diseases. Recent studies have suggested that curcumin (the active ingredient in turmeric) could alleviate the process of neuroinflammatory disease. Thus, the present mini-review was conducted to summarize studies regarding cellular and molecular targets of curcumin relevant to neuroinflammatory disorders. METHODS: A literature search strategy was conducted for all English-language literature. Studies that assessed the various properties of curcuminoids in respect of neuroinflammatory disorders were included in this review. RESULTS: The studies have suggested that curcuminoids have significant anti- neuroinflammatory, antioxidant and neuroprotective properties that could attenuate the development and symptom of neuroinflammatory disorders. Curcumin can alleviate neurodegeneration and neuroinflammation through multiple mechanisms, by reducing inflammatory mediators (such as TNF-α, IL-1ß, nitric oxide and NF-κB gene expression), and affect mitochondrial dynamics and even epigenetic changes. CONCLUSION: It is a promising subject of study in the prevention and management of the neuroinflammatory disease. However, controlled, randomized clinical trials are needed to fully evaluate its clinical potential.

A Novel Combination of ω-3 Fatty Acids and Nano-Curcumin Modulates Interleukin-6 Gene Expression and High Sensitivity C-reactive Protein Serum Levels in Patients with Migraine: A Randomized Clinical Trial Study.

BACKGROUND: Migraine is a disabling neuroinflammatory condition characterized by increasing the levels of interleukin (IL)-6, a proinflammatory cytokine and C-reactive protein (CRP) which considered as a vascular inflammatory mediator, disrupting the integrity of blood-brain barrier and contributing to neurogenic inflammation, and disease progression. Curcumin and ω-3 fatty acids can exert neuroprotective effects through modulation of IL-6 gene expression and CRP levels. The aim of present study is the evaluation of combined effects of ω-3 fatty acids and nano-curcumin supplementation on IL-6 gene expression and serum level and hs-CRP levels in migraine patients. METHODS: Eighty episodic migraine patients enrolled in the trial and were divided into four groups as 1) combination of ω-3 fatty acids (2500 mg) plus nano-curcumin (80 mg), 2) ω-3 (2500 mg), 3) nanocurcumin (80 mg), and 4) the control (ω-3 and nano-curcumin placebo included oral paraffin oil) over a two-month period. At the beginning and the end of the study, the expression of IL-6 from peripheral blood mononuclear cells and IL-6 and hs-CRP serum levels were measured, using a real-time PCR and ELISA methods, respectively. RESULTS: The results showed that both of ω-3 and nano-curcumin down-regulated IL-6 mRAN and significantly decreased the serum concentration. hs-CRP serum levels significantly decrease in combination and nano-curcumin within groups (P<0.05). An additive greater reduction of IL-6 and hs-CRP was observed in the combination group suggested a possible synergetic relation. CONCLUSION: It seems that ω-3 fatty acids and curcumin supplementation can be considered a new promising target in migraine prevention.

The Combined Effects of ω -3 Fatty Acids and Nano-Curcumin Supplementation on Intercellular Adhesion Molecule-1 (ICAM-1) Gene Expression and Serum Levels in Migraine Patients.

BACKGROUND: Migraine is an episodic headache, which is an endothelial disorder with neurological inflammation. Intercellular Adhesion Molecule-1 (ICAM-1), as an endothelial factor, leads to the adhesion of leukocytes to the walls of the cerebral blood vessels, which is an important step in the inflammation process. Curcumin and omega-3 fatty acids, by affecting transcription factors, can regulate the gene expression and serum levels of ICAM-1. Thus, this study aimed to evaluate the synergistic effects of ω-3 fatty acids and nano-curcumin on ICAM-1 gene expression and serum levels in migraine patients. METHOD: This clinical trial study was conducted on 72 episodic migraine patients in 4 groups for 2 months, with patients receiving ω-3 fatty acids, nano-curcumin, a combination of them, or a placebo during the study. At the beginning and end of the study, the gene expression and serum level of ICAM-1 were measured by real-time PCR and ELISA. RESULT: The results showed no significant change in ICAM-1 gene expression in any of the 4 groups. The ICAM-1 serum concentration in the combination group, and omega-3 alone, showed a significant reduction at the end of the study compared to the beginning. In addition, a significant reduction in attack frequency was observed in the combination group. CONCLUSION: Considering the results of supplementation with omega-3 fatty acids plus curcumin led to reductions of both attack frequency and ICAM-1 serum level in patients, it seems that supplementation with these two nutrients not only can lead to improvements in the function of metabolic pathways, but can also be used effectively as a treatment or prevention of migraine complications.

Molecular mechanisms of omega-3 fatty acids in the migraine headache.

Migraine is a common chronic inflammatory neurological disease with the progressive and episodic course. Much evidence have shown a role of inflammation in the pathogenesis of migraine. Omega-3 fatty acids are an important components of cell membranes phospholipids. The intake of these fatty acids is related to decrease concentration of C-reactive protein (CRP), proinflammatory eicosanoids, cytokines, chemokines and other inflammation biomarkers. Many of clinical trials have shown the beneficial effect of dietary supplementation with omega-3 fatty acids in inflammatory and autoimmune diseases in human, including Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD), multiple sclerosis (MS) and migraine headaches. Therefore, omega-3 fatty acids as an alternative therapy can be potentially important. This review focuses on the pathogenesis of a migraine, with an emphasis on the role of omega-3 fatty acid and its molecular mechanisms.