A Metabolic Study of Natural Products (Turmeric and Cinnamon), Cognitive Biomarkers and Working Memory among Pre-diabetes

• Main Authors: Lu, Ting-Mei, 呂婷玫
• Other Authors: Lee, Meei-Shyuan
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/22897348608977293296

碩士 === 國防醫學院 === 公共衛生學研究所 === 102 === Dementia is a general term of symptoms associated with a decline in the brain by progressive neurodegeneration. Alzheimer’s disease (AD) is the most common type of dementia. Plaques and tangles tend to be pathological features of AD comprised of extracellular deposits of amyloid protein and intracellular deposits of twisted fibers of tau protein respectively. Studies have implicated diabetes in the development for dementia, and suggested that glucose levels might contribute to AD-type neuropathology. Turmeric and cinnamon are widely used as food spices and potentially regulate glucose metabolism. Curcumin extracted from turmeric has also shown effects on alleviating neuron damage. Therefore, we hypothesized that these natural products affect the expression of the key biomarkers of cognitive dysfunction such as amyloid precursor protein, γ-secretase subunits presenilin-1, presenilin-2, and glycogen synthase kinase, and may affect working memory. This metabolic study aimed to evaluate whether natural products turmeric or cinnamon or combination alter cognition among pre-diabetes. Elders with fasting blood glucose 100-126 mg/dL were recruited from Tri-service General Hospital. 45 participants were divided into 4 groups (placebo, turmeric or cinnamon only and both combined) by double-blinded and gender-stratified blocked allocation. Participants were asked to keep fasting after 10 pm the previous day. On study day, participants checked in before 7:30 am. After taking fasting blood, working memory (WM) pre-test and measuring anthropometric data, a standardized breakfast and drugs were distributed at 8am. Each treatment contained 8 capsules followed by group1: placebo, group2: 2g of cinnamon, group3: 1g of turmeric, group4: 2g of cinnamon and 1g of turmeric. . Blood samples were collected at baseline and at 2, 4, and 6 hours after the start of the intervention. WM post-test was given after the last blood drawing. The mRNA expression of biomarkers was measured in peripheral blood mononuclear cells by RT-PCR. The result showed that turmeric, but not cinnamon, significantly improves WM. Glucose is negative correlated with WM but non-significant. We speculate turmeric itself appears to influence cognitive function rather than collaborate with glucose or biomarkers in synergism. Turmeric, which improved memory, might therefore act on brain function through its metabolic effects.