Alzheimer's disease, AD, is a neurodegenerative disorder with a limited number of therapeutic options. Curcumin is the main biologically-active constituent found in turmeric, which is a well known spice used in Indian cooking. AD is believed to be driven primarily by plaque growth on neuronal cells. Curcumin has shown beneficial effects as an alternative treatment for AD by inhibiting molecular pathways leading to the production of plaques. However, always consult a neurologist before treating nervous disorders with herbal supplements.
Plaque Formation in AD
Amyloid β, or Aβ, plaques are considered to be possible targets for therapy and diagnosis of AD. In the February 2011 issue of "Biomaterials," researchers showed that curcumin targets Aβ plaques and interferes with their formation, which suggests a potential role for treatment of AD. The authors used chemical methods to generate nanoliposomes, microscopic vessels made of fats, containing a curcumin derivative that was stable for periods of up to 20 days. They measured the binding capabilities of these liposomes to Aβ plaques and found a very high affinity potentially offering a new targeted delivery system of therapeutic molecules for AD treatment.
Role of Metals
The disruption of metal interactions with Aβ plaques holds considerable promise as a rational therapy against the development of AD. An article appearing in the November 2010 issue of "Expert Opinion on Therapy Targets" investigated the chelating properties of curcumin on the localization and removal of zinc, iron, copper and aluminum, which act as a catalyst for Aβ plaque formation in AD. The authors found that the interactions of metals with the metal-responsive elements on proteins involved in the progression of AD were inhibited by curcumin.
Biological Activities of Curcumin
Curcumin possesses potent and extensive biological activities, including anti-inflammatory and antioxidant activities, chemopreventative effects, and effects on the movement of proteins. The September 2010 issue of the "Journal of Biological Chemistry" includes a study that investigated the effects of curcumin on Aβ levels and Aβ precursor proteins in various nerve cell lines. The authors showed for the first time that curcumin potently lowers Aβ levels by inhibiting the maturation of the proteins in a secretory pathway, which allows the transportation of the plaques. This study provides a compelling mechanism of action for the ability of curcumin to influence Aβ pathology.
Spatial Learning and Memory
A study published in the September 2010 issue of "Neuroscience" investigated the effects of a curcumin mixture on spatial learning and memory in Aβ protein-infused rat models of AD. The researchers studied the gene expression of factors leading to the production of Aβ plaques and documented any memory-enhancing effect in the test animals. The study found that this compound altered gene expression levels in the hippocampus of the test animals and prevented the formation of precursor molecules leading to plaques, which suggested there are possibly multiple target sites with the potential of enhancing spatial memory in AD sufferers.
References
- "Journal of Biological Chemistry"; Curcumin decreases amyloid-beta peptide levels by attenuating the maturation of amyloid-beta precursor protein; C. Zhang et al; September 2010
- "Expert Opinion on Therapy Targets"; Novel drug targets based on metallobiology of Alzheimer's disease; S. Bandyopadhyay et al; November 2010
- "Biomaterials"; Curcumin-decorated nanoliposomes with very high affinity for amyloid-β1-42 peptide; S. Mourtas et al; February 2011
- "Neuroscience"; Curcuminoids enhance memory in an amyloid-infused rat model of Alzheimer's disease; T. Ahmed et al; September 2010
