In vitro effects of a polyphenol-rich blueberry extract on adult human neural progenitor cells

Authors: ZHENG, TONG - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; BIELINSKI, DONNA - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; Fisher, Derek; Shukitt-Hale, Barbara; STEINDLER, DENNIS - Jean Mayer Human Nutrition Research Center On Aging At Tufts University

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/21/2018
Publication Date: 11/3/2018
Citation: Zheng, T., Bielinski, D.F., Fisher, D.R., Shukitt Hale, B., Steindler, D.A. 2018. In vitro effects of a polyphenol-rich blueberry extract on adult human neural progenitor cells [abstract]. 2018 Society for Neuroscience Annual Meeting Program # 291.16.

Interpretive Summary:

Technical Abstract: The aging process affects all cells within the central nervous system, including neural stem cells. Significant declines in neurogenesis could contribute to neuronal dysfunction in aging. Pathology of aging and age-related neurodegeneration has been linked to increases in brain oxidative stress as well as inflammation, leading to interest in the protective effects of plant polyphenols, which possess both antioxidant and anti-inflammatory properties. Berries, including blueberry and strawberry, are rich in polyphenols and have been shown to improve cognition and memory in both aged animals and humans. While our previous studies have shown that blueberry and strawberry supplementations can increase neurogenesis in aged rodents, it is not clear whether this can be extrapolated to humans. We thus investigated the effects of berry fruit treatments on the viability, proliferation, and fate choice of adult human neural progenitor cells (AHNPs) that are neurogenic astrocytes potentially involved in memory and other brain functions. AHNPs from both control and Parkinson’s disease (PD) patients, isolated and characterized previously in our lab, were used here as an in vitro model for testing the effects of berry extract on human neural progenitor cells. AHNPs were cultured in N2 medium plus 5% fetal bovine serum, bovine pituitary extract and growth factors. Blueberry extract was prepared by homogenizing blueberries with deionized water (1:1 w/v) followed by centrifugation and freeze-drying. AHNPs were treated with blueberry extract at concentrations from 0.1 to 0.5 mg/ml for 5-7 days. The viability of cells was examined using the Trypan Blue exclusion method, and proliferation was evaluated using the ethynyl-deoxyuridine (EdU) assay. A subset of treated cells was labeled with antibodies against neuronal markers to examine the differentiation of these cells. To determine whether blueberry could protect AHNPs from induced oxidative stress by dopamine (DA) present in the media, some pre-treated cells were exposed to DA for 2 hours; their viability, proliferation, and calcium buffering were then examined. Our data show that blueberry has beneficial effects on the viability and proliferation of both human control- and PD-AHNPs. The extract was also able to reverse a decrease in viability, proliferation, and calcium buffering following stress induced by DA. Polyphenol-rich berry extracts thus confer a neuroprotective effect on control and Parkinson’s AHNPs, suggesting a role for dietary nutrients in helping to prevent and slow progression of neurodegenerative diseases.