The spice turmeric is a member of the Zingiberaceae (ginger family). Most usage of turmeric is in the form of powder from the roots, for color, and its medicinal value. Curcumin is the orange-yellow bioactive component of turmeric used to make curry in Indian cuisine. In Ayurvedic practices, turmeric is used as an antiseptic for cuts, burns and bruises and as an antibacterial agent. Turmeric is being investigated for possible benefits in pro-inflammatory conditions such as Alzheimer's disease.
Prevents Oxidation
Curcumin may protect against Alzheimer's disease by turning on a genetic code responsible for producing antioxidant proteins in the brain. The protective antioxidant system is called the heme oxygenase pathway. When curcumin triggers it in the brain tissue, the potent antioxidant bilirubin is produced. This antioxidant protects the brain from oxidative or free radical damage/injury. A study in the Italian Journal of Biochemistry, published in 2003, examined curcumin's role in this pathway. Since the brain is composed structurally of 60 percent fat, it is susceptible to free radical damage via oxidation. This oxidation may play a key role in the development of neurodegenerative disorders, age-related cognitive decline and dementia.
Inhibits Amyloid Plaque Formation
Alzheimer's disease results when a protein fragment called amyloid accumulates in brain cells. It produces oxidative stress which leads to chronic inflammation. Plaque forms between nerve cells (neurons) in the brain, disrupting proper cognitive function. In healthy brains, these protein fragments are broken down and eliminated from the body. In a study published in the Journal of Biological Chemistry in 2005, curcumin was injected into aged mice with advanced amyloid plaque accumulation. The curcumin crossed the blood-brain barrier and bound to the plaques, preventing clumping and plaque formation characteristic of advanced Alzheimer's. Curcumin has anti-inflammatory and antioxidant properties as well, which offers additional protection to brain cells.
Boosts Plaque Clearance
Turmeric may be beneficial in helping humans who already suffer from Alzheimer's disease. Another active ingredient in turmeric root, bisdemethoxycurcumin, boosts immune system activity in Alzheimer's patients. In healthy individuals, macrophages (a type of immune system cell) destroy abnormal cells. In Alzheimer's patients, macrophage activity (and the immune system) is suppressed. Macrophages are not able to effectively clear amyloid plaque. However, in a study published in the Proceedings of the National Academy of Sciences of the United States of America, researchers discovered that treating Alzheimer's patients' blood samples with bisdemethoxycurcumin boosted macrophage activity. It was more effective in clearing amyloid plaque in some of the blood samples, which indicates a genetic variable.
References
- "Advances in Experimental Medicine and Biology"; Antioxidant and anti-inflammatory properties of curcumin; V.P. Menon and A.R. Sudheer; 2007
- "The Italian Journal of Biochemistry"; Nutritional antioxidants and the heme oxygenase pathway of stress tolerance: novel targets for neuroprotection in Alzheimer's disease; V. Calabrese, D.A. Butterfield and A.M. Stella; December 2003
- "Journal of Biological Chemistry"; Curcumin inhibits formation of amyloid beta oligomers and fibrils, binds plaques, and reduces amyloid in vivo; F. Yang, G.P. Lim, A.N. Begum et al.; February 2005
- "Proceedings of the National Academy of Sciences of the United States of America"; Innate immunity and transcription of MGAT-III and Toll-like receptors in Alzheimer's disease patients are improved by bisdemethoxycurcumin; M. Fiala, P.T. Liu, A. Espinosa-Jeffrey, et. al.; July 2007
