Neuroprotective effects of quercetin 4’- O -β- d -diglucoside on human striatal precursor cells in nutrient deprivation condition

Abstract

Several investigations have demonstrated neuroprotective effects of quercetin, a polyphenol widely present in nature, against neurotoxic chemicals, as well as in neuronal injury/neurodegenerative disease models. Most of these studies have been performed with quercetin aglycone and its metabolites, while scanty data are available on its glycosides. This study is aimed at investigating the neuroprotective effects of quercetin 3,4'-O-β-d-diglucoside (Q3,4'dG), isolated from the bulbs of the white cultivar (Allium cepa L.), using an in vitro model of human striatal precursor cells (HSPs), a primary culture isolated from the striatal primordium and previously characterized. To study the effect of Q3,4'dG on cell survival, HSPs were exposed to nutrient deprivation created by replacing culture medium with phosphate buffer saline (PBS). Our findings showed that Q3,4'dG treatment significantly promoted cell survival and strongly decreased apoptosis induced by nutrient deprivation, as evaluated by cell proliferation/death analyses. In addition, since the adhesive capacities of cells are essential for cell survival, the expression of some adhesion molecules, such as pancadherin and focal adhesion kinase, was evaluated. Interestingly, PBS exposure significantly decreased the expression of both molecules, while in the presence of Q3,4'dG this effect was prevented. This study provides evidence of a neuroprotective role exerted by Q3,4'dG and suggests its possible implication in sustaining neuronal survival for prevention and treatment of neurodegenerative disorders.

Allium Flavonols: Health Benefits, Molecular Targets, and Bioavailability

“…These effects are ascribed to the strong antioxidant potential of flavonoids and their capacity to scavenge ROS [124]. A 3,4 -Qdg isolated from onion bulb protects human striatal precursor cells (HSPs) under nutrient deprived condition by reducing apoptosis and improving adhesion capacities via the expression of some adhesion molecules, such as pan-cadherin and focal adhesion kinase [90]. These studies indicate the potential application of Allium-derived flavonols in providing neuroprotective effects.…”

Benzo[a]pyrene impairs the migratory pattern of human gonadotropin-releasing-hormone-secreting neuroblasts

“…Cell viability was determined by MTT assay (Sigma-Aldrich), as previously described. 14 The immunocytochemistry was performed as previously described, 15 using rabbit anti-GnRH1 polyclonal antibody (1:100; Abcam, Cambridge, UK) and Alexa Fluor 488-conjugated as secondary antibody (1:200; Molecular Probes, Eugene, OR, USA). AlexaFluor 488-conjugated phalloidin (Molecular Probes) was used for cytoskeletal F-actin detection.…”

The Citrus Flavonoid Hesperetin Encounters Diabetes-Mediated Alzheimer-Type Neuropathologic Changes through Relieving Advanced Glycation End-Products Inducing Endoplasmic Reticulum Stress

“…Among the phytonutrients, flavanones have the highest bioavailability of flavonoid compounds [17]. Flavonoids play significant roles in neuroprotective applications, such as protecting against the development of dementia [18], promoting neuronal survival in nutrient deprivation conditions [19], and the emerging role as therapeutics against AD [20]. Hesperetin, a flavanone derivative, is widely distributed among plants and found in daily diets, predominantly in fruits and vegetables, which exhibits many beneficial actions, such as lessening the deterioration of diseases, including diabetes, hypertension, and arteriosclerosis [21].…”