Berries are well-known fruits for their antioxidant effects due to their high content of flavonoids, and quercetin is one of the potent bioactive flavonoids. Although oxidative stress is an inevitable outcome in cells due to energy uptake and metabolism and other factors, excessive oxidative stress is considered a pivotal mediator for the cell death and leads to the progression of neurodegenerative diseases (NDDs). Furthermore, oxidative stress triggers inflammation that leads to neuronal cell loss. Alzheimer’s, Parkinson’s, Huntington’s disease, amyotrophic lateral sclerosis, multiple sclerosis, and so on are the main neurodegenerative diseases. Hence, AD and PD are the most affected NDDs and cause the most lethality without any effective cure. Since AD and PD are the most common NDDs, therefore, in this study, we will describe the effect of oxidative stress on AD and PD. Targeting oxidative stress could be a very effective way to prevent and cure NDDs. Thus, the nuclear factor erythroid 2–related factor 2 (Nrf2) and heme oxygenase-1 (HO1) are potent endogenous antioxidant modulatory pathways, which also show cytoprotective activities. Modulation of Nrf2/HO1 signaling pathways through a biological approach could be an effective way to treat with NDDs. Quercetin is a natural polyphenol, which protects neurodegeneration, remarkably by suppressing oxidative stress and inflammation. Thus, quercetin could be a very effective agent against NDDs. We will discuss the benefits and challenges of quercetin to treat against NDDs, focusing on molecular biology.

Bilberry (Vaccinium myrtillus L.) is a medicinal fruit known for its high content of anthocyanins, flavonoids, vitamins, ascorbic acid, carotenoids, tocopherols and phenolic acid. Bilberry has long been used in oriental medicine for the prevention and treatment of various diseases, such as visual acuity, hyperglycemia, dyslipidemia, diabetes, cancer, obesity, inflammatory and cardiovascular diseases. In this study, we investigated using the antioxidant and anti-inflammatory of 70% ethanol extracts of bilberry in vitro. Antioxidant activities were measured with total phenolic, flavonoid and ascorbic acid contents. The bilberry extract (BE) showed significant free radical scavenging activities and inhibited oxidation of linoleic acid in a dose-dependent manner. BE also suppressed nitric oxide (NO) generation and reversed pro-inflammatory cytokines such as iNOS, COX-2, TNF-α and IL-6 in LPS-induced RAW 264.7 cells. From these results, we suggest that BE is a natural powerful antioxidant, and the anti-inflammatory agent being a rich source of anthocyanins.

Chronic ultraviolet (UV) exposure causes skin injury thorough the production of reactive oxygen species (ROS). Skin dryness, a characteristic of UV-induced injury, is closely related to skin barrier dysfunction. We investigated the effect of fermented black rice and blueberry with Lactobacillus plantarum (FBBBR) on UVB-induced skin injury. In vitro, FBBBR suppressed UVB-induced ROS generation, apoptosis, and metalloproteinase-9 expression, while increasing the expression of collagen type 1 alpha 1 (COL1A1) gene and natural moisturising factor-related genes such as filaggrin (FLG) and transglutaminase-1 (TGM-1). Oral administration of FBBBR increased serum catalase activity and decreased serum IgE levels, improved stratum corneum hydration and epidermal thickness and enhanced FLG, TGM-1, involucrin, and COL1A1 mRNA expression in dorsal skin in UVB-irradiated hairless mice. Therefore, we suggest that FBBBR can be used as a functional food with beneficial effects on skin hydration and skin barrier function.