125 research outputs found
Protective Effect of Strawberry Extract against Inflammatory Stress Induced in Human Dermal Fibroblasts
A protracted pro-inflammatory state is a major contributing factor in the development, progression and complication of the most common chronic pathologies. Fruit and vegetables represent the main sources of dietary antioxidants and their consumption can be considered an efficient tool to counteract inflammatory states. In this context an evaluation of the protective effects of strawberry extracts on inflammatory stress induced by E. coli LPS on human dermal fibroblast cells was performed in terms of viability assays, ROS and nitrite production and biomarkers of oxidative damage of the main biological macromolecules. The results demonstrated that strawberry extracts exerted an anti-inflammatory effect on LPS-treated cells, through an increase in cell viability, and the reduction of ROS and nitrite levels, and lipid, protein and DNA damage. This work showed for the first time the potential health benefits of strawberry extract against inflammatory and oxidative stress in LPS-treated human dermal fibroblast cells
Lipid Accumulation in HepG2 Cells Is Attenuated by Strawberry Extract through AMPK Activation
Regulation of lipid metabolism is essential for treatment and prevention of several chronic
diseases such as obesity, diabetes, and cardiovascular diseases, which are responsible for most
deaths worldwide. It has been demonstrated that the AMP-activated protein kinase (AMPK) has
a direct impact on lipid metabolism by modulating several downstream-signaling components.
The main objective of the present work was to evaluate the in vitro effect of a methanolic strawberry
extract on AMPK and its possible repercussion on lipid metabolism in human hepatocellular
carcinoma cells (HepG2). For such purpose, the lipid profile and the expression of proteins
metabolically related to AMPK were determined on cells lysates. The results demonstrated that
strawberry methanolic extract decreased total cholesterol, low-density lipoprotein (LDL)-cholesterol,
and triglycerides levels (up to 0.50-, 0.30-, and 0.40-fold, respectively) while it stimulated the
p-AMPK/AMPK expression (up to 3.06-fold), compared to the control. AMPK stimulation led
to the phosphorylation and consequent inactivation of acetyl coenzyme A carboxylase (ACC) and
inhibition of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), the major regulators of fatty
acids and cholesterol synthesis, respectively. Strawberry treatment also entailed a 4.34-, 2.37-, and
2.47-fold overexpression of LDL receptor, sirtuin 1 (Sirt1), and the peroxisome proliferator activated
receptor gamma coactivator 1-alpha (PGC-1α), respectively, compared to control. The observed
results were counteracted by treatment with compound C, an AMPK pharmacological inhibitor,
confirming that multiple effects of strawberries on lipid metabolism are mediated by the activation of
this protein.European Union (EU)
67930
Strawberry-Based Cosmetic Formulations Protect Human Dermal Fibroblasts against UVA-Induced Damage
Extreme exposure of skin to Ultraviolet A (UVA)-radiation may induce a dysregulated
production of reactive oxygen species (ROS) which can interact with cellular biomolecules leading
to oxidative stress, inflammation, DNA damage, and alteration of cellular molecular pathways,
responsible for skin photoaging, hyperplasia, erythema, and cancer. For these reasons, the use
of dietary natural bioactive compounds with remarkable antioxidant activity could be a strategic
tool to counteract these UVA-radiation-caused deleterious effects. Thus, the purpose of the present
work was to test the efficacy of strawberry (50 µg/mL)-based formulations supplemented with
Coenzyme Q10 (100 µg/mL) and sun protection factor 10 in human dermal fibroblasts irradiated
with UVA-radiation. The apoptosis rate, the amount of intracellular reactive oxygen species (ROS)
production, the expression of proteins involved in antioxidant and inflammatory response, and
mitochondrial functionality were evaluated. The results showed that the synergic topical use of
strawberry and Coenzyme Q10 provided a significant (p < 0.05) photoprotective effect, reducing cell
death and ROS, increasing antioxidant defense, lowering inflammatory markers, and improving
mitochondrial functionality. The obtained results suggest the use of strawberry-based formulations
as an innovative, natural, and useful tool for the prevention of UVA exposure-induced skin diseases
in order to decrease or substitute the amount of synthetic sunscreen agents
Polyphenol-Rich Strawberry Extract Protects Human Dermal Fibroblasts against Hydrogen Peroxide Oxidative Damage and Improves Mitochondrial Functionality
Strawberry bioactive compounds are widely known to be powerful antioxidants. In this study, the antioxidant and anti-aging activities of a polyphenol-rich strawberry extract were evaluated using human dermal fibroblasts exposed to H2O2. Firstly, the phenol and flavonoid contents of strawberry extract were studied, as well as the antioxidant capacity. HPLC-DAD analysis was performed to determine the vitamin C and β-carotene concentration, while HPLC-DAD/ESI-MS analysis was used for anthocyanin identification. Strawberry extract presented a high antioxidant capacity, and a relevant concentration of vitamins and phenolics. Pelargonidin- and cyanidin-glycosides were the most representative anthocyanin components of the fruits. Fibroblasts incubated with strawberry extract and stressed with H2O2 showed an increase in cell viability, a smaller intracellular amount of ROS, and a reduction of membrane lipid peroxidation and DNA damage. Strawberry extract was also able to improve mitochondrial functionality, increasing the basal respiration of mitochondria and to promote a regenerative capacity of cells after exposure to pro-oxidant stimuli. These findings confirm that strawberries possess antioxidant properties and provide new insights into the beneficial role of strawberry bioactive compounds on protecting skin from oxidative stress and aging
Strawberry (cv. Romina) Methanolic Extract and Anthocyanin-Enriched Fraction Improve Lipid Profile and Antioxidant Status in HepG2 Cells
Dyslipidemia and oxidation of low density lipoproteins (LDL) are recognized as critical factors in the development of atherosclerosis. Healthy dietary patterns, with abundant fruit and vegetable consumption, may prevent the onset of these risk factors due to the presence of phytochemical compounds. Strawberries are known for their high content of polyphenols; among them, flavonoids are the major constituents, and it is presumed that they are responsible for the biological activity of the fruit. Nevertheless, there are only a few studies that actually evaluate the effects of different fractions isolated from strawberries. In order to assess the effects of two different strawberry extracts (whole methanolic extract/anthocyanin-enriched fraction) on the lipid profile and antioxidant status in human hepatocellular carcinoma (HepG2) cells, the triglycerides and LDL-cholesterol content, lipid peroxidation, intracellular reactive oxygen species (ROS) content and antioxidant enzymes’ activity on cell lysates were determined. Results demonstrated that both strawberry extracts not only improved the lipid metabolism by decreasing triglycerides and LDL-cholesterol contents, but also improved the redox state of HepG2 cells by modulating thiobarbituric acid-reactive substances production, antioxidant enzyme activity and ROS generation. The observed effects were more pronounced for the anthocyanin-enriched fraction
Phenolic Compounds Isolated from Olive Oil as Nutraceutical Tools for the Prevention and Management of Cancer and Cardiovascular Diseases
Non-communicable diseases (NCDs) have become the largest contributor to worldwide
morbidity and mortality. Among them, cancer and cardiovascular diseases (CVDs) are responsible
for a 47% of worldwide mortality. In general, preventive approaches modifying lifestyle are more
cost-effective than treatments after disease onset. In this sense, a healthy diet could help a range
of NCDs, such as cancer and CVDs. Traditional Mediterranean Diet (MD) is associated by the
low-prevalence of certain types of cancers and CVDs, where olive oil plays an important role. In fact,
different epidemiological studies suggest that olive oil consumption prevents some cancers, as well as
coronary heart diseases and stroke incidence and mortality. Historically, the beneficial health effects
of virgin olive oil (VOO) intake were first attributed to the high concentration of monounsaturated
fatty acids. Nowadays, many studies indicate that phenolic compounds contained in olive oil have
positive effects on different biomarkers related to health. Among them, phenolic compounds would
be partially responsible for health benefits. The present work aims to explore, in studies published
during the last five years, the effects of the main phenolic compounds isolated from olive oil on
different cancer or CVD aspects, in order to clarify which compounds have more potential to be used
as nutraceuticals with preventive or even therapeutic properties
Phenolic Compounds in Honey and Their Associated Health Benefits: A Review
Honey is a natural substance appreciated for its therapeutic abilities since ancient times.
Its content in flavonoids and phenolic acids plays a key role on human health, thanks to the high
antioxidant and anti-inflammatory properties that they exert. Honey possesses antimicrobial capacity
and anticancer activity against different types of tumors, acting on different molecular pathways that
are involved on cellular proliferation. In addition, an antidiabetic activity has also been highlighted,
with the reduction of glucose, fructosamine, and glycosylated hemoglobin serum concentration.
Honey exerts also a protective effect in the cardiovascular system, where it mainly prevents the
oxidation of low-density lipoproteins, in the nervous system, in the respiratory system against
asthma and bacterial infections, and in the gastrointestinal system. A beneficial effect of honey can
also be demonstrated in athletes. The purpose of this review is to summarize and update the current
information regarding the role of honey in health and diseases
Beeswax by-Products Efficiently Counteract the Oxidative Damage Induced by an Oxidant Agent in Human Dermal Fibroblasts
The antioxidant capacity and the phytochemical composition of two by-products from
beeswax recycling processes were recently investigated. The aim of the present work was to
evaluate the efficacy of one of these by-products, MUD1, against the oxidative stress induced by
2,20-azobis(2-amidinopropane) dihydrochloride (AAPH) in human dermal fibroblast (HDF) cells.
After a preliminary viability assay, the protective effect of MUD1 was investigated through the
measurement of apoptosis level, the reactive oxygen species (ROS) and nitrite (NO2-) production,
the level of protein and lipid biomarkers (carbonyl groups, total glutathione and thiobarbituric
acid-reactive substance) of oxidative damage, and the measurement of antioxidant enzymes activities
(glutatione peroxidase, glutathione reductase, glutathione transferase, superoxide dismutase and
catalase). The obtained results showed that MUD1 exerted protective effects on HDF, increasing
cell viability and counteracted the oxidative stress promoted by AAPH-treatment, and improved
mitochondria functionality and wound healing capacities. This work shows the antioxidant effects
exerted by beeswax by-products, demonstrating for the first time their potential against oxidative
stress in human dermal fibroblast cells; however, further research will be necessary to evaluate their
potentiality for human health by more deeply in vitro and in vivo studies.The present study was partially funded by the “National Beekeeping Aid Program (Programa
Nacional de Ayudas a la Apicultura)”, cofounded by the European Union and assigned to Spanish FEGA and
FEAGA agencies. Patricia Reboredo-Rodríguez acknowledges award of a post-doctoral contract from Xunta
de Galicia
Fermi Large Area Telescope Constraints on the Gamma-ray Opacity of the Universe
The Extragalactic Background Light (EBL) includes photons with wavelengths
from ultraviolet to infrared, which are effective at attenuating gamma rays
with energy above ~10 GeV during propagation from sources at cosmological
distances. This results in a redshift- and energy-dependent attenuation of the
gamma-ray flux of extragalactic sources such as blazars and Gamma-Ray Bursts
(GRBs). The Large Area Telescope onboard Fermi detects a sample of gamma-ray
blazars with redshift up to z~3, and GRBs with redshift up to z~4.3. Using
photons above 10 GeV collected by Fermi over more than one year of observations
for these sources, we investigate the effect of gamma-ray flux attenuation by
the EBL. We place upper limits on the gamma-ray opacity of the Universe at
various energies and redshifts, and compare this with predictions from
well-known EBL models. We find that an EBL intensity in the optical-ultraviolet
wavelengths as great as predicted by the "baseline" model of Stecker et al.
(2006) can be ruled out with high confidence.Comment: 42 pages, 12 figures, accepted version (24 Aug.2010) for publication
in ApJ; Contact authors: A. Bouvier, A. Chen, S. Raino, S. Razzaque, A.
Reimer, L.C. Reye
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