Location: Jean Mayer Human Nutrition Research Center On Aging
2020 Annual Report
Objectives
Objective 1: Determine the effects of genetic, molecular and environmental influences on the aging brain, and the modifying impact of specific phytonutrients on neural cell function and behavior, including cognition.
Sub-Objective 1a: Characterize genetic and molecular signatures, especially pro-inflammatory markers, of normal adult brain stem/progenitor and differentiated cells, including neurons and microglia, in vitro and following the introduction of whole berry fruits and a combination phytonutrient: polymolecular botanical compound (PBC).
Sub-Objective 1b: Characterize genetic and molecular signatures of normal neural stem/progenitor and differentiated cells from Sub-Objective 1a in vivo following their grafting to the forebrains of immunocompromised mice, and subsequent feeding of the phytonutrients assayed in the in vitro model of Sub-Objective 1a.
Sub-Objective 1c: Characterize the genetic and molecular signatures, especially those associated with chronic inflammatory pathways, and the cognitive behavioral profile in aging models in rodents following feeding of phytonutrient compounds studied in Sub-Objectives 1a and b.
Sub-Objective 1d: Analyze biomarkers, especially those related to chronic inflammation and the cognitive behavioral profile, from liquid biopsies (e.g., serum) collected in human studies following phytonutrient supplementation with the candidate fruit and plant compounds studied in Sub-Objectives 1a-c.
Objective 2: Characterize in vitro and in vivo models that manifest aspects of human age-related neurological diseases, such as Parkinson’s and Alzheimer’s disease, for screening combinations of phytonutrient that can prevent or delay chronic inflammation and other deleterious micro-environmental conditions that contribute to cell degeneration in the neurodegenerative disorders.
Sub-Objective 2a: Characterize, in vitro, the genetic and molecular signatures, especially those associated with chronic inflammatory pathways, of stem/progenitor and differentiated neural and microglial cells (and exosomes isolated from them) isolated from patients with Parkinson’s Disease, following phytonutrient treatments studied in Objective 1.
Sub-Objective 2b: Characterize, in vivo, the genetic and molecular signatures (including mutant LRRK2-associated inflammation, stem cell and cell death/protection gene pathways) of cells, and exosomes derived from them, following xenotransplantation to the forebrain of immunocompromised mice and feeding of the phytonutrients studied in Objective 1.
Sub-Objective 2c: Characterize the genetic and molecular signatures of neural cells at-risk for abnormal functioning and cell death in transgenic mouse models of Parkinson’s disease, including behavioral studies, following feeding of candidate phytonutrient compounds studied in Objective 1.
Approach
As Americans are living longer, the incidence of age-related neurological disorders is a growing burden for older adults and the healthcare system. Our lab studies how plant-derived phytonutrients benefit the aging brain, especially in maintaining mobility and cognitive function and slowing the progression of neurological disease. Specifically, we look at the ways phytonutrients can counteract the changes in the aging brain that make it more susceptible to neurological disorders. We focus on the persistent activation of inflammatory pathways that reduce brain plasticity and, over time, contribute to destructive cellular changes which affect the nervous system’s functioning and ability to adapt to new experiences. We will analyze the anti-inflammatory properties of phytonutrient combinations and berries that contain numerous beneficial bioactives that target aging processes involving cellular communication and the propagation of disease. In vitro and in vivo bioassays utilizing human stem/progenitor cells and the brain’s innate immune cells, microglia, will be used to test combinations of phytonutrient components in normal aging and neuropathological models (i.e. Parkinson’s disease in the proposed studies here). Exosome microvesicles isolated from these assays are used as sensitive biomarkers for gene and protein expression patterns in interactive anti-inflammatory, neurogenic, and cell survival networks. Phytonutrient screening along with molecular and behavioral findings from cell culture, in vivo xenotransplantation, and human studies will establish phytonutrient effects that help counter neurodegeneration.
Progress Report
Progress was made on Objective 1 and its subobjectives which fall under NP107, Human Nutrition.
Under Sub-objective 1a, for this reporting period, researchers from the Neuroscience and Aging Lab in Boston, Massachusetts, established all cell lines needed for in vitro and in vivo studies proposed in the plan. Specifically, adult human neuronal progenitor cells (AHNPs) derived from various areas of human brains were established and used as in vitro assays for follow up treatments and evaluations. Rodent primary neurons and microglial cell lines were also established for similar studies. Human Induced Pluripotent Stem Cells (hiPSCs) are currently maintained in the lab for proposed in vivo xenograft studies (sub-objective 1b).
We also proposed to use sensitive biomarkers (exosomes/microvesicles) in this sub-objective to provide essential data on the roles for diet and nutrition in supporting healthy brain aging and cognitive function throughout life. We have developed the methods for isolation and characterization of the exosomes from our in vitro cell assays. A paper has been published that describes exosomes/microvesicles isolated from both control- and PD-derived human neural stem cells, as biomarkers in early-stage neurodegenerative disease. We anticipate using the readouts from molecularly profiling stem cell, neurogenesis and chronic inflammation-associated exosomal cargoes for the proposed nutrient testing of at-risk human neural stem and progenitor cells.
Under Sub-objective 1b, control hIPSCs proposed to be used as donor cells for the xenograft study were established and characterized. The human neural stem/progenitor cell xenograft model was also established, and baseline information related to the survival and differentiation of the donor cells was obtained for future comparison with xenografted animals undergoing diet treatments. A manuscript for the generation of this model was submitted for publication. Animal breeding has not been initiated due to the current pandemic situation. However, IACUC protocols are being prepared.
Under Sub-objective 1c, we began experiments to assess the association of metabolites that can cross the blood brain barrier with motor and cognitive alterations following continuous or intermittent wild blueberry supplementation in old rats. While studies from our laboratory and others have shown that continuous daily supplementation with blueberry can improve motor function and cognition, the optimal intake of blueberries is currently unknown, including if intermittent consumption differs from continuous consumption. Intermittent consumption of blueberries could: A) have a reduced beneficial effect due to the lower dose relative to continuous consumption, B) have the same effect as continuous consumption (e.g., if metabolites are retained in tissue), or C) have increased beneficial effects relative to continuous consumption due to the repeated stimulation of cellular repair mechanisms. Therefore, aged rats were fed either a continuous control diet, a continuous 2% blueberry diet, or intermittent 2% blueberry diet for 7-8 weeks prior to testing on a battery of age-sensitive tests. Psychomotor behavior was assessed using rod walking, plank walking, wire suspension, inclined screen, and rotarod, while cognitive behavior was assessed in the 8-arm radial arm water maze (RAWM).
In support of Sub-objective 1d, we began recruitment on a multi-center, double-blind, placebo-controlled, crossover study in older (55-70 year-old), overweight/obese (BMI 27-35) adults to study the effects of acute raspberry intake on the relationship between enhanced metabolic control and cognitive and psychomotor function. This project is in collaboration with Dr. Britt-Burton Freeman at Illinois Institute of Technology in Chicago. The aim of this project is to determine whether restoring meal-induced metabolic/inflammatory balance via supplementation with red raspberries results in improved cognitive performance in humans. Further, we are interested in determining if the expected enhancements are mediated through improvements in vascular function. Before recruitment began several steps were completed: test meals were developed and pilot tested for acceptance; cognitive assessment tools were set up; clinical procedures were reviewed at both sites for consistency; and ethics / IRB approval was obtained.
Accomplishments
1. Biomarkers of Parkinson's Disease. There is a need to identify sensitive signs of aging disorders, including Parkinson's and Alzheimer's disease early, to allow the use of diet and nutrition to delay the disorders. ARS researchers in Boston, Massachusetts, focused on one signal of Parkinson's disease risk and progression called "exosomes," which shows up when cells are stressed. This study shows that exosomes, which can be obtained non-invasively, may serve as sensitive biomarkers of Parkinson's disease.
Review Publications
Rutledge, G.A., Fisher, D.R., Miller, M.G., Kelly, M.E., Bielinski, D.F., Shukitt Hale, B. 2019. The effects of blueberry and strawberry serum metabolites on age-related oxidative and inflammatory signaling in vitro. Food and Function. 10(12):7707-7713. https://doi.org/10.1039/C9FO01913H.
Rabin, B.M., Miller, M.G., Larsen, A., Spadafora, C., Zolnerowich, N.N., Dell'Acqua, L.A., Shukitt Hale, B. 2019. Effects of exposure to 12C and 4He particles on cognitive performance of intact and ovariectomized female rats. Life Sciences in Space Research. 22:47-54. https://doi.org/10.1016/j.lssr.2019.07.005.
Carey, A.N., Fisher, D.R., Bielinski, D.F., Cahoon, D.S., Shukitt Hale, B. 2020. Walnut-associated fatty acids inhibit LPS-induced activation of BV-2 microglia. Inflammation. 43(1):241-250.
Sood, D., Tang-Schomer, M., Pouli, D., Mizzoni, C., Raia, N., Tai, A., Arkun, K., Wu, J., Black Iii, L.D., Scheffler, B., Georgakoudi, I., Steindler, D.A., Kaplan, D.L. 2019. 3D extracellular matrix microenvironment in bioengineered tissue models of primary pediatric and adult brain tumors. Nature Communications. 10:4529.
Candelario, K.M., Balaj, L., Zheng, T., Skog, J., Breakefield, X., Schule, B., Steindler, D. 2019. Exosome/microvesicle content is altered in leucine rich repeat kinase 2 mutant induced pluripotent stem cell derived neural cells. Journal of Comparative Neurology. https://doi.org/10.1002/cne.24819.
Pusey, M.A., Pace, K., Fascelli, M., Linser, P.J., Steindler, D.A., Galileo, D. 2019. Ectopic expression of L1CAM ectodomain alters differentiation and motility, but not proliferation, of human neural progenitor cells. International Journal of Developmental Neuroscience. 78:49-64. https://doi.org/10.1016/j.ijdevneu.2019.08.001.
