Location: Jean Mayer Human Nutrition Research Center On Aging
2016 Annual Report
Objectives
LAB NAME: Antioxidants Research
Objective 1. Determine the bioavailability, pharmacokinetics, metabolism, and mechanisms of phytochemicals (e.g., carotenoids, phenolic acids, polyphenols) from fruit, nuts, and whole grains using in vitro, animal model, and human studies.
Objective 2. Determine the effect of phytochemicals (e.g., alkylresorcinols, flavonoids) from fruit, nuts, and whole grains on intermediary biomarkers of age-related conditions (e.g., cytokines, isoprostanes), metabolomics parameters (e.g., fatty acids, organic acids), physiological profiles (e.g., endothelial responses, glucose homeostasis), and functional outcomes relevant to cardiovascular disease and type 2 diabetes.
Objective 3. Determine the effect of phytochemicals (e.g., anthocyanins, proanthocyanidins) from fruit, nuts, and whole grains on intermediary biomarkers of age-related conditions (e.g., oxidatively modified DNA) and physiological profiles (e.g., innate immunity) relevant to cancer, particularly colorectal and liver cancers.
Approach
LAB NAME: Antioxidants Research
Using in vitro, animal model, and human studies, we will characterize the bioavailability, pharmacokinetics, metabolism, and mechanisms of phytochemicals (e.g., carotenoids, phenolic acids, polyphenols) from fruit, nuts, and whole grains, particularly as relevant to the aging process and older adults. Building upon this information, we will determine the effect of phytochemicals (e.g., alkylresorcinols, flavonoids) from fruit, nuts, and whole grains on intermediary biomarkers of age-related conditions (e.g., cytokines, isoprostanes), metabolomic parameters (e.g., fatty acids, organic acids), physiological profiles (e.g., endothelial responses, glucose homeostasis), and functional outcomes relevant to cardiovascular disease and type 2 diabetes. In addition, we will investigate the effect of phytochemicals (e.g., anthocyanins, proanthocyanidins) from fruit, nuts, and whole grains on intermediary biomarkers of age-related conditions (e.g., oxidatively modified DNA) and physiological profiles (e.g., innate immunity) relevant to cancer, particularly colorectal and liver cancers.
Progress Report
Development of a method for quantification of cranberry proanthocyanin A2 dimer. Consumption of cranberries is associated with the reduction in risk of urinary tract infections, ulcers, and tooth decay through antibacterial, antiviral, and antioxidant activities. Proanthocyanins (PAC) are oligomeric flavonoids and present abundantly in cranberries. Most importantly, these compounds were found to be associated with a reduced risk of recurrent urinary tract infections by inhibiting E. coli adhesion to the wall of urinary tract. However, interpreting the varied results of human studies is confounded by lack of a valid biomarker(s) of their consumption. Here, we describe a sensitive analytical method for the quantification of urinary PAC from human subjects and test if its concentration can serve as a valid biomarker for the consumption of cranberry juice. After we established a reliable, sensitive analytical method for the quantification of cranberry PAC in human urine, we found that the urinary concentration of PAC is not likely to be a valid marker of cranberry intake. Thus, our study indicates that searching for a reliable, valid marker for consumption of cranberry juice and other related foods must continue as this marker will strengthen their link to health benefits.
By-product from red wine production maintains/improves gut health. Food residues derived from production of processed foods, e.g., wines, orange and grape juices, vegetable oils, dairy, and cereals, are generally underutilized. Using these food residues as ingredients for production of value added products in biotechnological applications, for example, enzymes and bioactive compounds, has been recognized. Grape pomace produced during the production of wine and grape juice contains fiber and phytochemicals, which have been known to confer an array of health benefits. In this study, we examined whether nutrients in grape pomace could exert antioxidant and anti-inflammatory actions in cultured intestinal cells. We found that nutrients in grape pomace could protect the intestinal cells against inflammation-induced damages, suggesting the potential of grape pomace for functional food developments.
A polyphenol found in herb displays a potential for treating diabetic cataracts. Cataracts are the leading cause for impaired vision and blindness in people with diabetes. While mechanism(s) by which the diabetic condition increases the risk of cataracts remains to be established, it has been known that high blood glucose can induce free radical induced damages in the eyes and subsequent development of cataracts. The reason that high blood glucose can induce these detrimental effects is that this condition enhances the activity of an enzyme, aldose reductase, which mediates the production of a harmful product, sorbitol, from glucose. Cataract surgery is effective to improve vision but the outcomes tend to be poor in patients with diabetes. Preclinical evidence has shown a variety of compounds found in edible plants and meats can delay, prevent, or even reverse the development of diabetic cataracts. Dendrobium aurantiacum var. denneanum (D. aurantiacum) has long been used in the traditional Chinese medicine to treat cataracts. However, what and how compounds in this herb exert its therapeutic effect are unclear. In this study, we demonstrated gigantol, a compound identified in this herb, could prevent or delay development of diabetic cataracts in rats. We also found that gigantol inhibited the activity of aldose reductase. Thus, our study suggests that gigantol in D. aurantiacum var. denneanum can be developed as a therapeutic agent for diabetic cataracts.
Alaska pollock skin collagen may be beneficial to gut health. A healthy gastrointestinal tract is crucial for health. Particularly, maintaining or restoring the integrity of the gut barrier between gastrointestinal lumen and the body can improve many health conditions because the healthy gut barrier is crucial for nutrient absorption and defense against harmful pathogens, toxins and dietary antigens. In this study, we examined whether Alaska pollock skin derived collagen and its peptides, which have been found to display an array of healthful attributes, can ameliorate inflammation-induced dysfunctions in cultured intestinal cells. We found that Pollock skin collagen peptides could attenuate inflammation-induced reduction in the integrity and permeability of the gut barrier. Thus, Alaska Pollock skin collagen peptides can be developed as function foods for gut health.
Lutein may play a role in the early cognitive development. Lutein, a dietary carotenoid commonly present in fruits and vegetables, selectively accumulates in human eyes and brain. While many studies show evidence of a relationship between lutein in the diet and body tissues and cognitive health, the reason for lutein’s selective uptake into human brain tissue is poorly understood. The objective of this study was to evaluate the relationship between levels of brain lutein and a known binding protein for lutein that is found in the eye among three age groups: infants, older adults, and centenarians. It was found that there was a strong relationship in infant brains, suggesting that this is the reason why there is selective uptake of lutein in early life and that it has a role in early cognitive development. The relationship remained significant but weaker in older adults and insignificant in centenarians. These findings suggest a decrease or abnormal function of lutein’s binding protein in human brain that may occur with aging. Given that this protein is also involved in cholesterol transportation within cells, a process that is affected in cognitive degenerative diseases, the potential protective function of lutein against these diseases remains to be explored.
Accomplishments
1. Dietary cholesterol was not associated with increased risk of various cardiovascular diseases. Dietary cholesterol has been thought to increase risk of cardiovascular disease outcomes. Tufts University researchers at USDA in Boston, Massachusetts, examined the effects of dietary cholesterol on cardiovascular disease outcomes in healthy adults by evaluating 39 published studies. They found that dietary cholesterol was not associated with increased risk of various CVD outcomes (ischemic heart disease death, ischemic stroke or hemorrhagic stroke). Dietary cholesterol significantly increased both blood levels of total cholesterol and LDL cholesterol, as well as blood levels of HDL cholesterol. These findings show that dietary cholesterol is not a risk factor for cardiovascular diseases in people with a normal capacity for cholesterol metabolism.
2. Almonds improve blood cholesterol in Korean Americans consuming traditional Korean diets. Almonds have been shown to reduce cardiovascular disease risk via the improvements in blood cholesterol and inflammation. As this health benefit is generally illustrated in people consuming American diets, whether this effect can be extended to ethnic groups remains unknown. Tufts University researchers at USDA in Boston, Massachusetts, conducted a human trial examining whether adding 2 oz almonds per day to Korean diets would improve nutrition quality and reduce blood cholesterol. They found that the addition of almonds decreased caloric intake from carbohydrates and increased from monounsaturated fats, as well as increased vitamin E and dietary fiber intakes. Consistent to the benefits in blood cholesterol found in Americans, almonds decreased blood cholesterol in overweight and obese Korean adults. Thus, Tufts researchers at the USDA in Boston, Massachusetts concluded that almonds replacing unhealthy snacks could improve nutritional status and decrease blood cholesterol in American Koreans who consume traditional Korean diets.
3. Avocados improve lutein status and may be part of a healthy diet for cognitive health. Lutein and zeaxanthin, dietary carotenoids, can cross the blood brain barrier and exclusively accumulate in the macular region of the retina in the eyes, where they are referred to as macular pigment (MP). MP density has been regarded as a valid marker of lutein levels in the brain. Tufts University researchers at USDA in Boston, Massachusetts, conducted a 6-month human trial with 40 heathy older adults to examine the effects of daily intake of 1 medium avocado or 1 cup of chickpeas on serum lutein levels, MPD and cognition. They found at 6 months, avocado consumption significantly increased serum lutein levels and MPD. Further, avocados improved working memory at 6 months, and the improvement in working memory was significantly related to the increase in MPD. Thus, These results show that frequent avocado consumption can increase lutein status and may serve as an effective dietary strategy for cognitive health.
None.
Review Publications
Blumberg, J.B., Vita, J.A., Chen, C. 2015. Concord grape juice polyphenols and cardiovascular risk factors: dose-response relationships. Nutrients. 7(12):10032-10052. doi:10.3390/nu7125519.
Ekinci, F.Y., Baser, G.M., Ozcan, E., Guclu-Ustundag, O., Korachi, M., Sofu, A., Blumberg, J.B., Chen, C. 2016. Characterization of chemical, biological and antiproliferative properties of fermented black carrot juice,shalgam . European Food Research and Technology. 242(8):1355-1368. doi: 10.1007/s00217-016-2639-7.
Trupia, S., Moser, J.K., Guney, A., Beckstead, R., Chen, C. 2016. Nutritional quality of eggs from hens fed distillers dried grains with solubles. Poultry Science. doi: 10.3382/ps/pew142.
Kamil, A., Smith, D.E., Blumberg, J.B., Astete, C., Sabliov, C., Chen, C. 2016. Bioavailability and biodistribution of nanodelivered lutein. Food Chemistry. 192:915-923. doi: 10.1016/j.foodchem.2015.07.106.
Hashimoto, N., Blumberg, J.B., Chen, C. 2016. Hyperglycemia and anthocyanin inhibit quercetin metabolism in HepG2 cells. Journal of Medicinal Food. 19(2):141-147.
Walsh, J.M., Ren, X., Zampariello, C., Polasky, D.A., Mckay, D.L., Blumberg, J.B., Chen, C. 2016. Liquid chromatography with tandem mass spectrometry quantification of urinary proanthocyanin A2 dimer and its potential use as a biomarker of cranberry intake. Journal of Separation Science. 39(2):342-349.
Erdman, J.W., Smith, J.W., Kuchan, M.J., Mohn, E., Johnson, E.J., Rubakhin, S.S., Wang, L., Sweedler, J.V., Neuringer, M. 2015. Lutein and brain function. Foods. 4(4):547-564.
Wu, J., Lu, C., Li, X., Fang, H., Wan, W., Yang, Q., Sun, X., Wang, M., Hu, X., Chen, C., Wei, X. 2015. Synthesis and biological evaluation of novel gigantol derivatives as potential agents in prevention of diabetic cataract. PLoS One. 10(10):e0141092. doi: 10.1371/journal.pone.0141092.
Lieblein-Boff, J.C., Johnson, E.J., Kennedy, A.D., Lai, C., Kuchan, M.J. 2015. Exploratory metabolomic analyses reveal compounds correlated with lutein concentration in frontal cortex, hippocampus, and occipital cortex of human infant brain. PLoS One. 10(8):e136904. doi: 10.1371/journal.pone.0136904.
Hruby, A., Mckeown, N.M. 2016. Magnesium deficiency: What is our status. Nutrition Today. 51(3):121-128.
