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Effect of blueberry ingestion on natural killer cell counts, oxidative stress, and inflammation prior to and after 2.5 h of running

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Blueberries are rich in antioxidants known as anthocyanins, which may exhibit significant health benefits. Strenous exercise is known to acutely generate oxidative stress and an inflammatory state, and serves as an on-demand model to test antioxidant and anti-inflammatory compounds. The purpose of this study was to examine whether 250 g of blueberries per day for 6 weeks and 375 g given 1 h prior to 2.5 h of running at ∼72% maximal oxygen consumption counters oxidative stress, inflammation, and immune changes. Twenty-five well-trained subjects were recruited and randomized into blueberry (BB) (N = 13) or control (CON) (N = 12) groups. Blood, muscle, and urine samples were obtained pre-exercise and immediately postexercise, and blood and urine 1 h postexercise. Blood was examined for F₂-isoprostanes for oxidative stress, cortisol, cytokines, homocysteine, leukocytes, T-cell function, natural killer (NK), and lymphocyte cell counts for inflammation and immune system activation, and ferric reducing ability of plasma for antioxidant capacity. Muscle biopsies were examined for glycogen and NFkB expression to evaluate stress and inflammation. Urine was tested for modification of DNA (8-OHDG) and RNA (5-OHMU) as markers of nucleic acid oxidation. A 2 (treatment) × 3 (time) repeated measures ANOVA was used for statistical analysis. Increases in F₂-isoprostanes and 5-OHMU were significantly less in BB and plasma IL-10 and NK cell counts were significantly greater in BB vs. CON. Changes in all other markers did not differ. This study indicates that daily blueberry consumption for 6 weeks increases NK cell counts, and acute ingestion reduces oxidative stress and increases anti-inflammatory cytokines.
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Effect of blueberry ingestion on natural killer cell
counts, oxidative stress, and inflammation prior to
and after 2.5 h of running
Lisa S. McAnulty, David C. Nieman, Charles L. Dumke, Lesli A. Shooter,
Dru A. Henson, Alan C. Utter, Ginger Milne, and Steven R. McAnulty
Abstract: Blueberries are rich in antioxidants known as anthocyanins, which may exhibit significant health benefits. Strenous
exercise is known to acutely generate oxidative stress and an inflammatory state, and serves as an on-demand model to test anti-
oxidant and anti-inflammatory compounds. The purpose of this study was to examine whether 250 g of blueberries per day for
6 weeks and 375 g given 1 h prior to 2.5 h of running at 72% maximal oxygen consumption counters oxidative stress, inflam-
mation, and immune changes. Twenty-five well-trained subjects were recruited and randomized into blueberry (BB) (N= 13) or
control (CON) (N= 12) groups. Blood, muscle, and urine samples were obtained pre-exercise and immediately postexercise,
and blood and urine 1 h postexercise. Blood was examined for F2-isoprostanes for oxidative stress, cortisol, cytokines, homo-
cysteine, leukocytes, T-cell function, natural killer (NK), and lymphocyte cell counts for inflammation and immune system acti-
vation, and ferric reducing ability of plasma for antioxidant capacity. Muscle biopsies were examined for glycogen and NFkB
expression to evaluate stress and inflammation. Urine was tested for modification of DNA (8-OHDG) and RNA (5-OHMU) as
markers of nucleic acid oxidation. A 2 (treatment) × 3 (time) repeated measures ANOVA was used for statistical analysis. In-
creases in F2-isoprostanes and 5-OHMU were significantly less in BB and plasma IL-10 and NK cell counts were significantly
greater in BB vs. CON. Changes in all other markers did not differ. This study indicates that daily blueberry consumption for
6 weeks increases NK cell counts, and acute ingestion reduces oxidative stress and increases anti-inflammatory cytokines.
Key words: F2-isoprostanes, antioxidants, blueberries, immunity, exercise, inflammation.
Résumé : Les bleuets sont riches en antioxydants notamment en anthocyanines qui sont bénéfiques sur le plan de la santé.
Lexercice intense suscite en peu de temps, on le sait, un stress oxydatif et un état inflammatoire, ce qui en fait un modèle pour
tester des composés aux propriétés antioxydantes et anti-inflammatoires. Cette étude veut vérifier leffet de lapport quotidien
de 250 g de bleuets durant 6 semaines plus lapport de 375 g 1 h avant une séance de course dune durée de 2,5 h à une inten-
sité sollicitant 72 % du consommation maximale doxygène inhibe le stress oxydatif, linflammation et les modifications du
système immunitaire. On sollicite 25 sujets bien entraînés et on les répartit aléatoirement dans lun des deux groupes : avec ap-
port de bleuets (BB, n= 13) et témoin (CON, n= 12). Avant le début de la séance et immédiatement après, on prélève des
échantillons de sang, durine et de tissu musculaire ; 1 h après la fin de la séance, on prélève des échantillons de sang et
durine. Pour évaluer le stress oxydatif, on analyse les F2-isoprostanes; pour évaluer le degré dinflammation et lactivation du
système immunitaire, on analyse le cortisol, les cytokines, lhomocystéine, les leucocytes, la fonction des lymphocytes T, les
cellules NK et la numération lymphocytaire ; pour évaluer le pouvoir antioxydant, on analyse la capacité plasmatique de réduc-
tion des ions ferriques. Pour évaluer le degré de stress et dinflammation, on analyse le glycogène et lexpression de NF-kB
dans le tissu musculaire prélevé. Pour évaluer loxydation des acides nucléiques, on analyse dans lurine la quantité de
8-OHdG de l'ADN et de 5-OHMU de lARN. Lanalyse statistique consiste en une analyse de variance 2 (traitement) × 3
(moment) avec mesures répétées. Comparativement au groupe témoin, on observe dans le groupe BB significativement plus de
F2-isoprostanes, moins de 5-OHMU et plus de cellules NK et dIL-10 dans le plasma. On nobserve aucune différence pour
tous les autres marqueurs. Daprès les observations de cette étude, lapport quotidien de bleuets durant 6 semaines augmente le
nombre de cellules NK et un seul apport diminue le stress oxydatif et augmente le nombre de cytokines anti-inflammatoires.
Motsclés : F2-isoprostanes, antioxydants, bleuets, immunité, exercice physique, inflammation.
[Traduit par la Rédaction]
Received 22 April 2011. Accepted 1 September 2011. Published at www.nrcresearchpress.com/apnm on 23 November 2011.
L.S. McAnulty. Department of Nutrition and Health Care Management, Appalachian State University, Boone, NC 28608, USA.
D.C. Nieman, L.A. Shooter, A.C. Utter, and S.R. McAnulty. Department of Health, Leisure, and Exercise Science, Appalachian State
University, Boone, NC 28608, USA.
C.L. Dumke. Department of Health and Human Performance, University of Montana, Missoula, MT 59812, USA.
D.A. Henson. Department of Biology, Appalachian State University, Boone, NC 28608, USA.
G. Milne. Department of Biomedical Research Education and Training, Vanderbilt University, Nashville, TN 37240, USA.
Corresponding author: Steven R. McAnulty (e-mail: mcanltysr@appstate.edu).
976
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Introduction
Reactive oxygen species (ROS) are involved in the etiol-
ogy of aging, carcinogenesis, and the pathophysiology of
many diseases (Carlström et al. 2011; Halliwell and White-
man 2004; Halliwell 2007). Given the involvement of ROS
in vascular diseases and detrimental cellular processes, re-
search has focused on the potential beneficial effects of anti-
oxidant consumption and suppression of oxidative stress
(Schiffrin 2010; McAnulty et al. 2008). Evidence exists that
suggests that edible berries may have many beneficial effects
related to bioactive phytochemicals contained by the fruits,
which include flavonoids and proanthocyanins (Manach and
Donovan 2004). Specifically, blueberries contain large
amounts of anthocyanins (Zheng and Wang 2003). Anthocya-
nins are polyphenolic ring-based flavonoids that are found in
fruits and vegetables of redblue color, such as blueberries.
Epidemiological evidence indicates that the moderate con-
sumption of anthocyanins is associated with reduced risk of
cardiovascular disease (Hou et al. 2003). In animal models,
blueberry ingestion has been found to be important in pre-
venting degeneration in neural and cerebellar function from
ROS (Wang et al. 2005) and in preventing inflammation
from tumor necrosis factor (Youdim et al. 2002). These ben-
efits may derive from the antioxidant capabilities of antho-
cyanins which, in the serum, have been directly correlated
with an increase in serum antioxidant capacity.
Another interesting activity associated with berry antho-
cyanins may be the the ability to inhibit growth of several
types of human cancers. The anticancer effects are mediated
through inhibition of oxidative stress, inflammation, inflam-
matory cytokines, and regulation of carcinogen metabolizing
enzymes, various transcription and growth factors, and sub-
cellular signaling pathways of cancer cell proliferation
(Seeram 2008). One potential aspect of anthocyanin activity
against cancer cells involves natural killer cells (NK cells),
which represent a subset of peripheral lymphocytes that play
a critical role in the innate immune response to virus-infected
and tumor-transformed cells (Vojvodićand Popović2010). It
is thought that a better understanding of dietary and nutra-
ceutical compounds that activate and promote NK-cell func-
tion will broaden the applications for human cancer (Jha et
al. 2010). Thus far, the majority of berry research in regard
to health benefits has been limited to in vitro and animal ap-
plications, which do not allow a complete understanding of
the parameters of intake, bioavailability, and metabolism,
which actually occur in vivo (Stoner et al. 2010; Paul et al.
2010; Zhu et al. 2008).
Exercise can be used as a stimulus to induce increased ox-
idative stress and inflammation and, as such, provide a way
to test the antioxidant, signaling, and anti-inflammatory prop-
erties of blueberries (McAnulty et al. 2003; Nieman et al.
2007). Despite the acute increase in oxidative stress and in-
flammation, exercise-induced oxidative stress results in bene-
ficial adaptations and up-regulation of various antioxidant
enzymes (Powers et al. 2010). The purpose of the present
study was to examine the antioxidant and anti-inflammatory
mechanisms of blueberries. Although findings from this
study may have broader implications for the general popula-
tion or for specific disease states, the intent of the study was
not to investigate, determine, or suggest that reduction of ex-
ercise-induced oxidative stress by antioxidant compounds
should be utilized.
Therefore, given the potential health benefits of increasing
flavonoids such as anthocyanins in the diet, our aim was to
examine whether blueberries given in amounts roughly equal
to 50% of the suggested daily fruit recommendations would
counter exercise-induced changes in oxidative stress markers
(plasma F2-isoprostanes and urinary DNA and RNA modi-
fied bases), antioxidant status (ferric-reducing ability of
plasma (FRAP)), immune and inflammatory factors (cyto-
kines, NK cells), and transcription factors (muscle NFkB).
To our knowledge, this study represents the first attempt to
evaluate the effects of blueberry anthocyanins on these pa-
rameters prior to and after exhaustive exercise in humans.
We hypothesized that blueberry consumption would result in
change related to exercise-induced oxidative stress, inflam-
mation, and immunity before and after exhaustive running in
well-trained athletes.
Materials and methods
Subjects
Twenty-five trained subjects were recruited and random-
ized into either blueberry (BB) (N= 13) or control (CON)
(N= 12) groups. One to 3 weeks prior to beginning the
study, subjects reported to the Appalachian State University
Human Performance Laboratory for fitness testing and as-
sessment. Written informed consent was obtained from each
subject, and the experimental procedures were approved by
the Institutional Review Board of Appalachian State Univer-
sity.
Research design
Within 1 week prior to the start of supplementation, sub-
jects reported to the university Human Performance Lab for
orientation and measurement of maximal oxygen consump-
tion (
_
VO2max).
_
VO2max was determined using a graded maxi-
mal protocol adapted for runners with oxygen uptake and
ventilation measured using the MedGraphics CPX metabolic
system (MedGraphics Corp., St. Paul, Minn., USA). Heart
rate was measured using a chest heart rate monitor (Polar
Electro Inc., Woodbury, N.Y., USA). Basic demographic and
training data were obtained through a questionnaire. Body
composition was measured using hydrostatic weighing. At
that time, the subjects assigned to the BB group were given
10.5 kg of pre-packaged blueberries (250 g servings) in a
cooler. Subjects were told to incorporate 250 g of blueberries
per day into the diet for 6 weeks prior to returning to the lab-
oratory for a 2.5-h treadmill run. The subjects were only re-
quired to consume the total 250 g within the 24-h period.
The CON group simply followed their usual diet. Obviously,
the nature of the study prevented any attempt at blinding re-
garding the subjects.
After 6 weeks, subjects reported back to the lab to com-
plete a 2.5-h treadmill run at 72%
_
VO2max. In addition to
the chronic supplementation, subjects assigned to the BB
group consumed an acute dose of 375 g blueberries after the
initial blood draw and muscle biopsy and within 1 h prior to
exercise testing to investigate potential short-duration effects
of blueberry consumption. Immediately postexercise, a sec-
ond blood sample and muscle biopsy was obtained, and at
McAnulty et al. 977
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1 h postexercise a final blood sample was obtained. Subjects
reported to the lab at 0600 hours not having ingested energy
in any form for at least 8 h. The runs were conducted over a
5-week period with 46 runners on treadmills in the same
room at the same time on the same day of the week (0700
0930 hours, Saturday), with metabolic measures collected
every 30 min to verify workload (using the same equipment
used during baseline testing). Except for water ad libitum,
subjects were prohibited from ingesting any form of energy
or nutritional supplement during the run.
Subjects in both groups were instructed to avoid all nutri-
tional supplementation and anti-inflammatory medications
during the 6 weeks prior to the testing protocol. Throughout
the 6-week pre-test period, all subjects were directed to fol-
low a diet (using a food list provided by the research dieti-
tian), of which certain foods high in vitamins C and E were
prohibited. The subjects completed a 7-day food record dur-
ing the final week of the 6-week pre-test period to evaluate
similarity of diets. Compliance was monitored by asking par-
ticipants to return empty zip lock bags. Diet records were an-
alyzed using an ESHA Food Processor (version 11; Salem,
Ore., USA) for energy, macronutrient, and specific micro-
nutrient (vitamins C and E, b-carotene, copper, manganese,
selenium, and zinc) content.
Blood and urine samples
Blood samples were collected into heparinized and EDTA
vacutainer tubes. The tubes were immediately placed on ice
and then spun at 1000gfor 10 min at 4 °C. The plasma
from the heparin tubes was aliquoted into cryotubes, snap
frozen in liquid nitrogen, and stored at 80 °C until analysis
for F2-isoprostanes and FRAP. Urine was collected into
specimen containers and then aliquoted and snap frozen in
liquid nitrogen. All assay determinations were accomplished
within 2 months of the end of the study and were corrected
for plasma volume shift according to the methodology of Dill
and Costill (1974).
Muscle biopsies, glycogen, and NFkB determination
Muscle biopsies were obtained from the vastus lateralis
pre-exercise and immediately postexercise. Post-biopsy was
obtained 2 cm proximal from the pre-test biopsy site. Local
anesthesia (2% xylocaine) was injected subcutaneously and
intramuscularly. Following a small incision with a scalpel
(0.5 cm), a muscle biopsy sample (75 mg) was obtained
using the percutaneous needle biopsy procedure modified to
include suction. Muscle was trimmed of connective tissue
and fat and immediately frozen in liquid nitrogen. Muscle
samples were homogenized in 0.3 mol·L1PCA and glyco-
gen digested by the amyloglucosidase method (Passonneau
and Lauderdale 1974). The resulting glucose moieties were
quantified spectrophotometrically in the presence of hexoki-
nase and glucose-6-phosphate dehydrogenase. NFkB (p50)
was determined using an ELISA kit (10006912) from Cay-
man Chemical (Ann Arbor, Mich., USA).
Oxidative stress measures
F2-isoprostanes
Plasma F2-isoprostanes were determined using gas chroma-
tography mass spectrometry (GC-MS) as previously de-
scribed (Milne et al. 2007). Briefly, free F2-isoprostanes
were extracted from plasma added to a deuterated [2H4]
PGF2ainternal standard. The mixture was then added to a
C18 Sep Pak column, followed by silica solid phase extrac-
tions. F2-isoprostanes were converted to pentafluorobenzyl
esters, subjected to thin layer chromatography, and converted
to trimethylsilyl ether derivatives. Samples were analyzed by
a negative ion chemical ionization GC-MS using an Agilent
6890N gas chromatography interfaced to an Agilent 5975B
inert MSD mass spectrometer (Agilent Technologies Inc.
Santa Clara, Calif., USA).
Oxidized nucleic bases
RNA and DNA oxidatively modified base assays for
5-hydroxymethyl-2-deoxyuridine (5-OHMU) and 8-hydroxy-
2-deoxy guanosine (8-OHDG), respectively, were deter-
mined by Kronos Laboratory (Phoenix, Ariz., USA) using
standardized liquid chromatography-mass spectrometry
(LC-MS) methodologies.
Antioxidant measures
Ferric Reducing Antioxidant Potential (FRAP)
Total plasma antioxidant potential was determined by the
FRAP assay according to the methodology of Benzie and
Strain (1996). The basis of this assay is that water soluble re-
ducing agents (antioxidants) in the plasma will reduce ferric
ions to ferrous ions, which then react with an added chromo-
gen. Samples and standards were analyzed in duplicate and
expressed as ascorbate equivalents based on a physiologic as-
corbate standard curve (01000 µmol). Intra-assay and inter-
assay coefficients of variation were less than 5% and 7%,
respectively.
Homocysteine and cortisol
Plasma homocysteine was assayed in duplicate and deter-
mined by a standard protocol from an ELISA kit provided
by Axis-Shield Laboratories (Heidelberg, Germany). Plasma
cortisol was assayed in duplicate using the competitive solid-
phase 125I radioimmunoassay (RIA) technique (Diagnostic
Products Corp., Los Angeles, Calif., USA).
Cytokines, complete blood counts, hemoglobin, hematocrit
Enzyme-linked immunosorbant assays were used, in ac-
cordance with the manufacturer protocol, to measure total
plasma concentrations of IL-1 receptor antagonist (IL-1ra),
interleukin-6 (IL-6 and IL-6 high sensitivity), interleukin-8,
interleukin-10 (IL-10) (R&D Systems Inc., Minneapolis,
Minn., USA), and IL-10 Ultra Sensitive (BioSource Interna-
tional Inc., Camarillo, Calif., USA). All samples and pro-
vided standards were analyzed in duplicate. High sensitivity
kits were used to analyze pre-exercise and postexercise IL-6
and IL-10 samples. Pre-exercise and postexercise samples
were analyzed on the same assay plate to decrease interkit as-
say variability. Data were analyzed with SOFTmax software
(Molecular Devices, Sunnyvale, Calif., USA). Routine com-
plete blood counts (CBCs) were performed by our clinical
hematology laboratory using a Coulter STKS instrument
(Coulter Electronics, Hialeah, Fla., USA) and provided he-
moglobin and hematocrit.
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Lymphocyte subsets
Lymphocyte subset data (%T, %B, and %NK) were ob-
tained by flow cytometry. Briefly, peripheral blood mononu-
clear cells were isolated from heparinized whole blood by
density gradient centrifugation with Fico/Lite (cat. no.
I40150; Atlanta Biologicals, Atlanta, Ga., USA). The lym-
phocytes were gated using intracellular complexity (side scat-
ter) and FITC fluorescence intensity (CD45+), and flow
cytometric dot plots of CD19-ECD vs. CD3-PC5 and CD56-
PE vs. CD3-PC5 were produced. In this manner, the percent-
age of lymphocytes that were NK cells (CD56+ CD3-), B-
cells (CD19+ CD3-), and T-cells (CD3+ CD19-) was deter-
mined for each subject. Absolute numbers of each cell type
were then calculated using the CBC data to allow group com-
parison of circulating cell counts.
Phytohemagglutinin (PHA)-stimulated lymphocyte
proliferation
The mitogenic response of lymphocytes was determined in
whole blood culture using PHA at optimal and suboptimal
doses previously determined by titration experiments. Hepari-
nized venous blood was diluted 1:10 with complete media
consisting of RPMI-1640 supplemented with 5% heat-inacti-
vated fetal bovine serum, penicillin, streptomycin, sodium
pyruvate, L-glutamine, b-2-mercaptoethanol, and Mito+ Se-
rum Extender (cat. no. 355006; Becton Dickinson Immuno-
cytometry Systems, San Jose, Calif., USA). PHA was
prepared in RPMI-1640 media at a concentration of
1 mg·mL1and then further diluted with complete media to
the optimal and suboptimal working concentrations (6 and
12 µg·mL1, respectively). A 100 µL aliquot of the diluted
blood was dispensed into each of triplicate wells of a 96-well,
flat-bottom microtiter plate. To each well, 100 µL of the
appropriate mitogen dose was added. Control wells received
complete media instead of mitogen. After a 72-h incubation
at 37 °C and 5% CO2, the cells were pulsed with 1 µCi of
thymidine (methyl)-3H (New England Nuclear, Boston,
Mass., USA) prepared with RPMI-1640. After pulsing, cells
were incubated for an additional 4 h before harvesting. The
radionucleotide incorporation was assessed by a Wallac
1209 RackBeta Liquid Scintillation Counter (Gaithersburg,
Md., USA) with the results expressed as experimental minus
control counts per minute.
Statistical analysis
All data are expressed as means ± SD. Data in Table 1
were compared between groups using 1-way ANOVA. Data
in Tables 2 and 3 and Figs. 1 to 5 were analyzed using a
2 (groups) × 3 (times) repeated measures ANOVA. Main ef-
fects of treatment, time, and treatmenttime interaction were
determined by the method of GreenhouseGeiser. If signifi-
cant treatment by time interaction was detected, differences
between and within treatments for specific times were com-
pared between groups using 1-way ANOVA with significance
set at p0.025 after Bonferroni correction to account for
multiple comparisons. All data were screened for outliers
with an outlier being designated as outside of the mean ±2.5
standard deviations. Data designated as an outlier was re-
moved from all statistical analyses.
Results
Table 1 describes participant characteristics and perform-
ance values for BB and CON groups. Blueberry ingestion
did not result in changes for any performance indicator. Diet-
ary analysis indicated that macronutrient and micronutrient
content did not differ between groups (data not shown). Skel-
etal muscle glycogen was determined to access overall exer-
cise stress and any potential differences in metabolism.
Glycogen declined similarly by approximately 61% in both
groups following the 2.5-h run (Fig. 1). F2-isoprostanes ex-
hibited significant interaction effects (p= 0.016) and in-
creased immediately postexercise 129% in CON compared
with 55% in BB (Fig. 2). Cortisol decreased by 10% and
23%, respectively, in BB and CON from pre-exercise to 1 h
postexercise, but the pattern of change was not different be-
tween groups (Fig. 3). Skeletal muscle NFkB activity in-
creased significantly immediately following the run (p=
0.002), but the pattern of change was not different between
treatments (Fig. 4). The urinary modified RNA base marker
5-OHMU declined significantly postexercise in BB compared
with the decline observed in CON (p= 0.028), but the DNA
marker 8-OHDG was not significantly altered (Table 2). The
FRAP plasma antioxidant potential significantly increased in
BB (23%) and CON (17%) following exercise (p0.001),
but the pattern of change was not different between groups
(Table 2).
Plasma IL-10 was significantly elevated after exercise in
BB vs. CON (p= 0.045) (Table 3). Plasma IL-1ra, IL-6, IL-8,
and homocysteine significantly increased after exercise (p
0.05), but the patterns of change were not different between
groups (Table 3). The mitogen-induced lymphocyte prolifer-
ative response decreased postexercise for both groups in a
similar pattern (Table 3). NK cells were higher in BB com-
pared with CON, being 96%, 122%, and 76% greater, re-
spectively, at the 3 sampling times. NK cells exhibited
significant group (p= 0.003), time (p0.001), and inter-
action (p= 0.047) effects. After a Bonferroni correction
(p< 0.025) and further examination, NK cells remained
significantly higher at all 3 sampling times (Fig. 5). The
pattern of change in total blood leukocytes, neutrophils,
monocytes, lymphocytes, T lymphocytes, and B lymphocytes
did not differ between groups (data not shown).
Table 1. Subject characteristics and performance measures.
Blueberry Control
Age (y) 31.1±12.6 33.4±16.0
Height (m) 1.76±0.1 1.72±0.1
Weight (kg) 71.7±10.0 72.3±15.1
_
VO2max (mL·kg1·min1)47.61±9.0 45.32±7.0
% Body fat 11.9±8.5 14.4±5.6
Average (km·wk1) 48.7±25.9 62.2±30.2
RER at 2.5 h 0.84±0.1 0.86±0.1
_
VO2(L·min1) at 2.5h 2.21±4.44 2.16±5.46
RPE at 2.5 h 13.2±3.3 13.0±2.4
HR (beats·min1) at 2.5h 151±18.2 150±23.2
Note: Values are means ± SD. Means did not differ between
groups for any variable (p0.05). Blueberry, N= 13; control, N=
12.
_
VO2max, maximal oxygen consumption; RER, respiratory ex-
change ratio;
_
VO2, volume of oxygen; RPE, ratings of perceived ex-
ertion; HR, heart rate.
McAnulty et al. 979
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Table 2. Urinary oxidative (8-OHDG, 5-OHMU) and plasma antioxidant capacity markers (FRAP).
Blueberry Control Treatment time interaction
(pvalue)Pre-exercise Postexercise 1 h postexercise Pre-exercise Postexercise 1 h postexercise
8-OHDG (N= 10) (mg·g1creatine) 7.9±4.4 9.6±10.6 6.6±3.0 7.3±4.8 7.9±4.6 6.1±3.0 0.601
0.439
0.877
5-OHMU (N= 10) (mg·g1creatine) 7.4±6.3 4.9±4.2 3.0±2.5 7.1±6.6 6.4±3.0 6.5±5.9 0.028
0.380
0.431
FRAP (N= 11) (µmol·L1ascorbate
equivalents)
577.7±88.3 716.3±77.2 633.4±79.9 596.5±114.5 698.9±106 624.1±75 0.893
<0.001
0.811
Note: Values are means ± SD. Differences in Nreflect losses in sample processing and removal of outliers. 8-OHDG, 8-hydroxy-deoxyguanodine; 5-OHMU, 5-hydroxy-methyluracil; FRAP, ferric-reducing
ability of plasma.
Table 3. Plasma cytokines and homocysteine.
Blueberry (N= 13) Control (N= 12) Treatment time interaction
(pvalue)Pre-exercise Postexercise 1 h postexercise Pre-exercise Postexercise 1 h postexercise
IL-6 (pg·mL1) 1.1±0.3 15.5±1.9 8.3±1.0 0.6±0.7 10.8±1.9 6.4±0.7 0.059
0.001
0.210
IL-8 (pg·mL1) 15.3±1.6 20.4±2.0 16.9±2.0 16.7±4.1 20.4±4.9 19.8±5.0 0.740
0.011
0.467
IL-10 (pg·mL1) 1.1±0.4 13.7±3.3 9.8±2.0 0.6±0.2 7.6±2.4 3.8±0.9 0.045
0.001
0.200
IL-1ra (pg·mL1) 150.3±21.2 350±5.7 07.5±256.5 206.1±26.7 311.3±37.2 386±88.8 0.493
0.045
0.366
PHA-12 18.1±2.8 16.6±3.2 13.2±1.3 23.8±4.1 19.0±3.7 20.5±3.5 0.222
0.095
0.261
Hcy (µmol·L1) 6.7±2.1 11.8±4.8 9.1±4.7 6.6±4.1 9.0±4.7 9.2±4.5 0.617
<0.001
0.372
Note: Values are means ± SD. IL, interleukin; PHA, plasma hemaglutin activator; Hcy, homocysteine.
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Discussion
The main findings from this study were that consumption
of 250 g of blueberries daily for 6 weeks and 375 g of blue-
berries given 1 h prior to running for 2.5 h at 72%
_
V
_
O2max
resulted in significant reductions in plasma F2-isoprostanes,
urinary 5-OHMU, and significant increases in plasma IL-10
postexercise. Most interestingly, NK cell counts were almost
doubled in the blueberry group prior to exercise, and this in-
crease was maintained throughout the exercise. To our
knowledge, this large increase in NK cells has never before
been demonstrated in humans consuming blueberries. Blood
NK cell counts typically decrease after prolonged endurance
exercise, but the high pre-exercise NK cell levels in the blue-
berry group helped maintain postexercise counts close to
those of the control group prior to exercise (Horn et al.
2007). Although a study limitation is that a baseline value
was not established prior to supplementation, our subjects
were randomized to the respective treatment groups. There-
fore, the randomization associated with the very strong treat-
ment effect deems it unlikely that anything other than the
blueberry ingestion was responsible for the differences in
NK cell counts.
Cellular components of both the innate and the adaptive
arms of the immune system are important in controlling tu-
mor growth. Specifically, NK cells are emerging as key com-
ponents in functioning between innate and adaptive immunity
in combating cancer (Stagg and Smyth 2007). Although no
evaluation of any type or risk of disease state was conducted
in this study, our outcomes regarding reductions in oxidative
stress, increases in NK cells, and anti-inflammatory cytokines
coincide with growing evidence from tissue culture, animal,
and clinical models that support a benefit associated with
0
20
40
60
80
100
120
140
160
180
Pre- exercise Postexercise
(µmol·g wet tissue)
–1
Blueberry Control
Skeletal muscle glycogen
Fig. 1. Skeletal muscle glycogen over time in blueberry (N= 13)
and control groups (N= 10). Main effects were treatment (p=
0.884), time (p0.001), and interaction (p= 0.901). Values are
means ± SD.
0
20
40
60
80
100
120
Pre- exercise Postexercise 1.5 h postexercise
Plasma F
2-isoprostanes (pg·mL )
–1
Blueberry Control
*
**
Fig. 2. Plasma F2-isoprostanes over time in blueberry and control
groups (N= 10). Main effects were treatment (p= 0.016), time (p
0.001), and interaction (p= 0.007). Since interaction was signifi-
cant, point to point comparisons were examined after a Bonferroni
correction to p0.025. ***, Significantly different from control
value (p0.001). Values are means ± SD.
0
100
200
300
400
500
600
700
800
900
Pre-exercise Postexercise 1.5 h postexercise
Plasma cortisol (nmol·L )
–1
Blueberry Control
Fig. 3. Plasma cortisol over time in blueberry (N= 13) and control
groups (N= 12). Main effects were treatment (p= 0.335), time (p=
0.068), and interaction (p= 0.254). Values are means ± SD.
0
10
20
30
40
50
60
70
Pre-exercise Postexercise
(ug /10 µL wet muscle)
Blueberry Control
NFKB p65
Fig. 4. Skeletal muscle NFkB over time in blueberry (N= 8) and
control groups (N= 7). Main effects were treatment (p= 0.159),
time (p= 0.002), and interaction (p= 0.906). Values are means ±
SD.
McAnulty et al. 981
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flavonoid consumption. These models suggest flavonoid
compounds may influence the development of cancer and
vascular diseases such as atherosclerosis, ischemic stroke,
and neurodegenerative diseases of aging which are associated
with increased oxidative stress and inflammation. Anthocya-
nins specifically are capable of influencing mechanisms that
counteract oxidative stress, decrease inflammation, and mod-
ulate expression of genes associated with disease (Neto 2007).
Our exercise stress model induced significant oxidative
stress, and F2-isoprostane values were more than doubled im-
mediately postexercise in the controls compared with the BB
group. We have routinely observed increases in F2-isopros-
tanes from various exercise protocols (McAnulty et al. 2005,
2007, 2010). The measurement of F2-isoprostanes provides
an accurate assessment of oxidative stress both in vitro and
in vivo and is the most reliable index of oxidative stress
(Milne et al. 2007). In addition to specificity and reliability,
F2-isoprostanes exhibit biological activity in vitro,causing
smooth muscle vasoconstriction and platelet aggregation. F2-
isoprostanes are produced by non-cylooxygenase free radical
mediated lipid peroxidation of arachidonic acid, which was
inhibited postexercise by the acute consumption of blueber-
ries . Because this is a novel finding, little information exists
as to the magnitude or importance of this result in relation to
prolonged exercise.
Blueberries were also effective at reducing oxidation of
some genetic material as we observed a decrease in urinary
5-OHMU but not 8-OHDG when compared with controls.
Oxidation of cytidine results in formation of uridine oxidates
which can be detected in vivo.In partial support of our find-
ings, Reichhold et al. (2009) found that ultra endurance types
of exercise did not result in DNA damage, but unfortunately
RNA oxidative markers were not examined. The reason for
this difference cannot be ascertained from this study, and we
can only speculate that perhaps the nucleus is better shielded
from ROS.
Despite the reductions seen with F2-isoprostanes and uri-
nary 5-OHMU, plasma antioxidant capacity as determined
by the FRAP assay was not different between groups. Several
explanations for these findings are possible. Formation of F2-
isoprostanes and urinary 5-OHMU may be influenced by
blueberry polyphenols in a way not reflected by the FRAP
assay. Our results indicate that polyphenolic compounds lose
the ability to function as typical reducing compounds after
absorption, most likely because of the extensive conjugation
(Rechner et al. 2002a). Therefore, flavonoids most likely
function in ways such as cell signaling that have little or
nothing to do with antioxidant function.
Blueberry ingestion resulted in higher postexercise plasma
concentrations of the anti-inflammatory cytokine IL-10 com-
pared with controls. Magrone et al. (2008) found that red
wine polyphenols and Crouvezier et al. (2001) found that tea
polyphenols promoted IL-10 release in vitro, and provide
some support for our findings. IL-1ra, IL-6, and IL-8 were
all increased after exercise, as we have reported in a previous
study (Nieman et al. 2003), but no group differences existed
for these cytokines. The higher postexercise levels of plasma
IL-10 in the blueberry group do not appear to be related to
changes in skeletal muscle NFkB or muscle glycogen, as no
group differences were measured.
Our design emphasized the use of an exercise stress model
to determine if blueberry ingestion can counter postexercise
inflammation, oxidative stress, and immune changes. The
acute dose of blueberries ingested 1 h prior to exercise exhib-
ited the major influence on the group differences reported in
this paper (F2-isoprostanes, IL-10, and 5-OHMU), with the
exception of NK cell counts, which were elevated in the
blueberry group after chronic ingestion. The bioavailability
of blueberry anthocyanins is known to be low with a rapid
elimination rate (Rechner et al. 2002b), implying that poten-
tial bioactive influences are transient. However, little is
known regarding tissue incorporation of anthocyanins follow-
ing a chronic increase in ingestion and related influences on
the outcome measures included in this study.
In conclusion, we have demonstrated for the first time that
250 g of blueberries ingested daily for 6 weeks increased
basal NK cell counts, and acute ingestion (375 g) increased
plasma IL-10, and reduced plasma F2-isoprostanes and uri-
nary 5-OHMU in athletes following 2.5 h of intense running.
These effects occurred despite no group differences for exer-
cise-induced changes in plasma antioxidant capacity, other
cytokines, T-cell function, or muscle glycogen and NFkB
levels. In light of these findings, future studies should pursue
examinations that define critical amounts and length of blue-
berry consumption necessary to induce these effects. Trials
with sedentary individuals with certain disease states would
also be interesting. Last, the benefit or detrimental effects of
a reduction of F2-isoprostanes during exercise should con-
tinue to be examined.
Acknowledgements
Financial support for this study was provided by the North
American Blueberry Council and the North Carolina High-
bush Blueberry Council. There were no conflicts of interest.
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Pre-exercise Postexercise 1.5 h postexercise
Blood NK cells (10
9
/L)
Blueberry Control
*
*
**
*
*
*
*
Fig. 5. Blood natural killer cells over time in blueberry (N= 12)
and control groups (N= 11). Main effects were treatment (p=
0.003), time (p0.001), and interaction (p= 0.047). Since interac-
tion was significant, point to point comparisons were examined after
a Bonferroni correction to p0.025. **, Significantly different
from corresponding control value (p0.01); ***, significantly dif-
ferent from corresponding control value (p0.001). Values are
means ± SD.
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... In our study, no immune signals of unregulated inflammation (e.g., a dramatic increase of leukocytes and reduction of lymphocytes) were verified, which highlights diet adequacy and/or recovery efficacy. An adequate diet can boost immunocompetence and reduce inflammatory processes [67]. Micronutrient supplementation can improve the immune system only in situations of nutritional deficiency [68]. ...
... The effect of supplementation on NK cell concentration seems to be dependent on the supplement type and type of exertion. While blueberries, rich in vitamins and phytochemicals, improve immunity, increasing NK cell levels after long-lasting intense running [67], ginseng does not affect the immune response to moderate exercise [71]. It was also reported that acute multi-nutrient supplement ingestion (1000 mg quercetin, 120 mg epigallocatechin 3-gallate, 400 mg isoquercetin, 400 mg each eicosapentaenoic acid [EPA], and docosahexaenoic acid [DHA], 1000 mg vitamin C, and 40 mg niacinamide), 15 min before heavy exertion caused a strong increase in plasma quercetin levels but did not counter post-exercise inflammation or immune changes relative to placebo [72]. ...
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... Subsequent berry studies confirmed beneficial post-exercise recovery effects on running-induced (2.5 h at 72%VO 2max ) natural killer cells, oxidative stress and inflammation [blueberry (Vaccinium sect. Cyanococcus): (13)], effects on muscle damage and inflammation after a half-marathon [bilberry (Vaccinium myrtillus): (14)], and New Zealand blackcurrant effects on rowing-induced (30 min at 80%VO 2max ) oxidative stress and inflammation (5). The focus of the early berry studies [e.g., (3,5,13)] was on the recovery of exercise-induced inflammation and oxidative stress. ...
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... In view of the major impact of inflammation on the organism, supplementation with immunomodulatory substances would be beneficial [41][42][43][44][45]. Among many populations there is growing interest in regular physical exercise, often involving muscle strength training exercises [46][47][48][49][50][51]. This pattern of activity highlights the importance of incorporating antioxidant substances in the diet to counteract the possible negative effects of this exercise on the body [17,50]. ...
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... Particularly, the (poly)phenolic (PP) fraction of fruits, especially berries, has been acknowledged and demonstrated to be a component with significant health-promoting properties, through its anti-inflammatory and immune-modulating activities (Fraga et al., 2019;Shama, 2016;Folmer et al., 2014). The anti-inflammatory effect of berry PP have been demonstrated on the postprandial response to meals as well as to exercise-induced inflammation in humans, e.g. by reducing the circulatory postprandial level of C-Reactive protein, Plasminogen activator inhibitor-1, interleukin (IL)1β and IL-6 (Edirisinghe et al., 2011;Ellis et al., 2011;McAnulty et al., 2011). More studies yet have investigated the effect of berry extracts on chronic low-grade inflammation in groups of individuals suffering from overweight or metabolic syndrome (Chiva-Blanch, 2017) and, although not all studies demonstrated significant anti-inflammatory effects of the berry PP, the overall trend is an attitude towards mild anti-inflammatory effects. ...
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The immunomodulatory potential of probiotics and (poly)phenols (PP) is recognized; however, studies regarding microorganisms-PP synergisms are yet to be explored. Here, we investigated the cooperation between probiotics and berry-derived PP extracts in modulating the cytokine responses in dendritic cells. Bacteria elicited immune responses in a strain-dependent manner. PP extracts showed different modulation of cytokine triggered by bacteria. Also with LPS, used as pro-inflammatory stimulus, PP from blueberry (BB) and cranberry (CB) most efficiently reduced IL12 production. L. paracasei LPC-S01 and B. bifidum MIMBb23sg resulted the best bacterial association in abrogating IL12 and increasing IL10. The use of PP fraction from BB50f and CB1 with the LPC-S01 + MIMBb23sg association resulted the most efficient combinations in terms of anti-inflammatory activity. These results provide bases for further investigation in vivo, in the perspective to develop food supplements that might conceivably deliver the single and combined benefits of probiotics and berry (poly)phenols.
... [94] Blueberry fruit is safe when consumed in normal amounts [100] Cilantro (Coriandrum sativum) Metal-binding proteins Enhance mercury excretion and decrease lead absorption. ...
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Since the thyroid gland is one of the organs most affected by autoimmune processes, many patients with thyroiditis of Hashimoto (TH) seek medical advice on lifestyle variance and dietary modifications to improve and maintain their hyroid function. In this review, we aim to present and discuss some challenges associated with the nutritional management of TH, focusing on environmental and dietary deficits, inflammatory and toxic nutrients, cyanotoxins, etc. We discuss the relationships among different diets, chronic inflammation, and microbiota, and their impact on the development and exacerbation of TH in detail. We share some novel insights into the role of vitamin D and melatonin for preserving thyroid function during chronic inflammation in autoimmune predisposed subjects. A comprehensive overview is provided on anti-inflammatory nutrients and ecological diets, including foods for cleansing and detoxification, which represent strategies to prevent relapses and achieve overall improvement of life quality. In conclusion, data from biomedical and clinical studies provide evidence that an appropriate dietary and lighting regimen could significantly improve the function of the thyroid gland and reduce the reactivity of autoantibodies in TH. Compliance with nutritional guidelines may help TH patients to reduce the need for medicines.
... Initially, studies have indicated some diet alterations that might act in favor of the immune system. Meals filled with plants rich in antioxidants, for instance, may improve the immune system defenses against viral infections (114,115) (Figure 3): blueberry, for example, has been shown to increase the amount of NK cells and anti-inflammatory cytokines, upon acute ingestion (116). In contrast with that, processed oils (as opposed to short-chain fatty acids), for instance, shall be avoided, due to the demonstrated enhancement of a more proinflammatory state when ingested (117). ...
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COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been considered a public health emergency, extensively investigated by researchers. Accordingly, the respiratory tract has been the main research focus, with some other studies outlining the effects on the neurological, cardiovascular, and renal systems. However, concerning SARS-CoV-2 outcomes on skeletal muscle, scientific evidence is still not sufficiently strong to trace, treat and prevent possible muscle impairment due to the COVID-19. Simultaneously, there has been a considerable amount of studies reporting skeletal muscle damage in the context of COVID-19. Among the detrimental musculoskeletal conditions associated with the viral infection, the most commonly described are sarcopenia, cachexia, myalgia, myositis, rhabdomyolysis, atrophy, peripheral neuropathy, and Guillain-Barré Syndrome. Of note, the risk of developing sarcopenia during or after COVID-19 is relatively high, which poses special importance to the condition amid the SARS-CoV-2 infection. The yet uncovered mechanisms by which musculoskeletal injury takes place in COVID-19 and the lack of published methods tailored to study the correlation between COVID-19 and skeletal muscle hinder the ability of healthcare professionals to provide SARS-CoV-2 infected patients with an adequate treatment plan. The present review aims to minimize this burden by both thoroughly exploring the interaction between COVID-19 and the musculoskeletal system and examining the cutting-edge 3D cell culture techniques capable of revolutionizing the study of muscle dynamics.
... It was revealed that anthocyanins-and proanthocyanidins-rich portions of fermented blueberry-blackberry wine can inhibit lipopolysaccharide triggered inflammatory response in macrophages of mouse (Johnson et al., 2013). A growth in natural killer cell activity and anti-inflammatory cytokines along with reduction in oxidative stress was reported in highly fit athletes who were given 250 g of blueberries/day for 6 weeks, which clearly proved that there is a positive relation between the amount of anthocyanins and immune function (McAnulty et al., 2011). ...
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Our immune system depends on leucocytes or white blood cells which possess the power to produce antibodies to fight various disease‐causing pathogens. People have now realized the crucial role played by the immune system in keeping them healthy. Therefore, recent scenario has witnessed an upsurge in the demand of immunity boosting foods. The use of naturally available fruits as immunomodulators is so ubiquitous and just needs concrete scientific proofs for claiming its efficacy. Many studies have shown that fruits are abundant in bioactive compounds like vitamins (vitamin A, C, E, etc.), minerals, and phytochemicals (like β‐ carotene, flavonoids, tannins, and phenolics, etc.). These components have the potential to enhance our immunity by supporting the proliferation of lymphocytes, scavenging free radical species, reducing oxidative stress, improving anti‐inflammatory as well as immunomodulatory mechanism, and supporting aggregation of platelets. Thus, supplementation of diet with an appropriate amount of fruits daily could support body's natural defense by strengthening our immune response. In this preface, we attempt to summarize the significant role played by various phytochemicals and bioactive compounds of fruits in boosting our immune system.
... Total plasma antioxidant capacity was higher in the blueberry group post-muscle stress than in the placebo group. Muscle damaging exercise, such as eccentric exercise, is known to increase oxidant stress [9], and the increased antioxidant capacity noted in the current study is similar to what has been observed after blueberry consumption in runners (10) and young females after eccentric muscle stress (11). However, this is the first time this has been documented in older adults following muscle stress. ...
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Muscles of old adults respond to stress with heightened inflammatory signaling that disrupts the regenerative process. This muscle inflammation susceptibility could contribute to the age-related decline in muscle mass, as anti-inflammatory medications taken concurrently with exercise training, have proven beneficial in attenuating age-related loss of muscle mass. With antioxidants and anti-inflammatory potential, blueberries (BB) are a natural alternative that might regulate aged muscle inflammation susceptibility. Objectives: The purpose of this study was to determine the effects of BB consumption on the muscle inflammatory profile of older adults, and to determine the subsequent muscle inflammatory response to exercise. We hypothesized that BB would lower the inflammatory profile of muscle and attenuate the inflammatory response after resistance exercise. Design: Subjects were randomized to receive daily BB or placebo supplements, which were blind to subjects and researchers. All subjects underwent baseline functional testing, post-supplementation testing, and testing post-muscle stress stimulus. Setting: Volunteers were recruited from Western North Carolina region, USA. Participants: Healthy, non-resistance trained adults over 60 years old (n=22) were recruited. Measurements: Profiles of inflammation pathways known to affect muscle mass were established prior to and after 6-weeks of daily consumption of BB. Post-supplementation, subjects performed an exercise protocol to induce inflammation and returned 24 hours post-exercise to determine the muscle inflammatory profiles. Results: Muscle cytokine and soluble cytokine receptor levels were similar between groups and within groups before and after BB consumption. Cytokine and cytokine receptor levels post-muscle stress changed similarly in the BB and placebo group, indicating BB had no effect on the muscle’s inflammatory response. Total plasma antioxidant capacity was 22% higher in the BB group 24-hours post-muscle stress, however, plasma oxidative stress was not different between groups or within groups. Conclusion: While BB consumption did not affect inflammatory signaling pathways within the muscle nor affect inflammation after a regenerative stimulus, a higher plasma antioxidant capacity could contribute to a better long-term regenerative response.
... Highbush blueberries include three types: northern highbush blueberry (NHB), half highbush blueberry (HHB), and southern highbush blueberry (SHB). Blueberries are rich in bioactive compounds, mainly flavones and other polyphenolic compounds (Zeng et al., 2021), which confer strong antioxidant properties that provide health benefits and earn the blueberry the title of functional food (McAnulty et al., 2011). Anthocyanins, the major part of total phenolic compounds and the most important subclass of flavonoids, are ubiquitous in the world's fruits and vegetables (Koh, Xu, & Wicker, 2020b). ...
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Blueberry anthocyanins have received increasing attention for their remarkable antioxidant, vision improvement, anti-inflammatory and cardiovascular disease prevention properties. However, the application of blueberry anthocyanins is limited due to their instability and the difficulty in absorption and utilization by the human body. This review provides a comprehensive summary of the species of blueberry (genus Vaccinium), the distribution of those species and the bioactivity of blueberry anthocyanins. Furthermore, the current review discusses the applications of blueberry anthocyanin-rich extracts, challenges in their application, and strategies to improve their bioavailability in the process of further development in the food and nutrition industry.
... Pharmacological studies revealed that blueberry possesses anti-diabetic, anti-inflammatory, anti-tumor, and neuroprotective effects [119]. Evidence suggests that blueberry exhibited strong protection against inflammation in pre-clinical and clinical evaluations [120][121][122]. In a study by Goyarzu et al., the flavonoid-rich diets including the anti-oxidant rich blue berry were well reported to prevent cognitive impairment associated with inflammaging in animal studies [123]. ...
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Inflammaging, the steady development of the inflammatory state over age is an attributable characteristic of aging that potentiates the initiation of pathogenesis in many age-related disorders (ARDs) including neurodegenerative diseases, arthritis, cancer, atherosclerosis, type 2 diabetes, and osteoporosis. Inflammaging is characterized by subclinical chronic, low grade, steady inflammatory states and is considered a crucial underlying cause behind the high mortality and morbidity rate associated with ARDs. Although a coherent set of studies detailed the underlying pathomechanisms of inflammaging, the potential benefits from non-toxic nutrients from natural and synthetic sources in modulating or delaying inflammaging processes was not discussed. In this review, the available literature and recent updates of natural and synthetic nutrients that help in controlling inflammaging process was explored. Also, we discussed the clinical trial reports and patent claims on potential nutrients demonstrating therapeutic benefits in controlling inflammaging and inflammation-associated ARDs.
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The metabolic syndrome (MetS) comprises pathological conditions that include insulin resistance, arterial hypertension, visceral adiposity and dyslipidaemia, which favour the development of CVD. Some reports have shown that cranberry ingestion reduces cardiovascular risk factors. However, few studies have evaluated the effect of this fruit in subjects with the MetS. The objective of the present study was to assess the effect of reduced-energy cranberry juice consumption on metabolic and inflammatory biomarkers in patients with the MetS, and to verify the effects of cranberry juice concomitantly on homocysteine and adiponectin levels in patients with the MetS. For this purpose, fifty-six individuals with the MetS were selected and divided into two groups: control group (n 36) and cranberry-treated group (n 20). After consuming reduced-energy cranberry juice (0·7 litres/d) containing 0·4 mg folic acid for 60 d, the cranberry-treated group showed an increase in adiponectin (P= 0·010) and folic acid (P= 0·033) and a decrease in homocysteine (P< 0·001) in relation to baseline values and also in comparison with the controls (P< 0·05). There was no significant change in the pro-inflammatory cytokines TNF-α, IL-1 and IL-6. In relation to oxidative stress measurements, decreased (P< 0·05) lipoperoxidation and protein oxidation levels assessed by advanced oxidation protein products were found in the cranberry-treated group when compared with the control group. In conclusion, the consumption of cranberry juice for 60 d was able to improve some cardiovascular risk factors. The present data reinforce the importance of the inverse association between homocysteine and adiponectin and the need for more specifically designed studies on MetS patients.
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Recently, cherries and cherry products have received growing attention within the literature with regards to their application in both exercise and clinical paradigms. Reported to be high in anti-inflammatory and anti-oxidative capacity, cherries and their constituents are proposed to provide a similar, but natural alternative akin to over-the-counter non-steroidal anti-inflammatory drugs (NSAID’s) or analgesics. Within exercise paradigms, concern has been raised with regards to the use of products which inhibit such inflammatory or oxidative actions, due to the possibility of the blunting of physiological training adaptations. Despite this, numerous scenarios exist both within exercise and clinical populations where a goal of optimal recovery time is more important than physiological adaptation. This review critically evaluates and discusses the use of cherries as a supplementation strategy to enhance recovery of muscle function, inhibit exercise-induced inflammation, oxidative stress and pain primarily; furthermore the potential application of cherries to clinical populations is discussed
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Background: Exercise-induced muscle damage (EIMD) is accompanied by localized oxidative stress / inflammation which, in the short-term at least, is associated with impaired muscular performance. Dietary antioxidants have been shown to reduce excessive oxidative stress; however, their effectiveness in facilitating recovery following EIMD is not clear. Blueberries demonstrate antioxidant and anti-inflammatory properties. In this study we examine the effect of New Zealand blueberries on EIMD after strenuous eccentric exercise. Methods: In a randomized cross-over design, 10 females consumed a blueberry smoothie or placebo of a similar antioxidant capacity 5 and 10 hours prior to and then immediately, 12 and 36 hours after EIMD induced by 300 strenuous eccentric contractions of the quadriceps. Absolute peak and average peak torque across the knee, during concentric, isometric, and eccentric actions were measured. Blood biomarkers of oxidative stress, antioxidant capacity, and inflammation were assessed at 12, 36 and 60 hours post exercise. Data were analyzed using a two-way ANOVA. Results: A significant (p < 0.001) decrease in isometric, concentric and eccentric torque was observed 12 hours following exercise in both treatment groups. During the 60 hour recovery period, a significant (p = 0.047) interaction effect was seen for peak isometric tension suggesting a faster rate of recovery in the blueberry intervention group. A similar trend was observed for concentric and eccentric strength. An increase in oxidative stress and inflammatory biomarkers was also observed in both treatment groups following EIMD. Although a faster rate of decrease in oxidative stress was observed in the blueberry group, it was not significant (p < 0.05) until 36 hours post-exercise and interestingly coincided with a gradual increase in plasma antioxidant capacity, whereas biomarkers for inflammation were still elevated after 60 hours recovery. Conclusions: This study demonstrates that the ingestion of a blueberry smoothie prior to and after EIMD accelerates recovery of muscle peak isometric strength. This effect, although independent of the beverage's inherent antioxidant capacity, appears to involve an up-regulation of adaptive processes, i.e. endogenous antioxidant processes, activated by the combined actions of the eccentric exercise and blueberry consumption. These findings may benefit the sporting community who should consider dietary interventions that specifically target health and performance adaptation.
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Unlabelled: INTRODUCTION; Natural Killer cells (NK cells) represent the subset of peripheral lymphocytes that play critical role in the innate immune response to virus-infected and tumor transformed cells. Lysis of NK sensitive target cells could be mediated independently of antigen stimulation and without requirement of peptide presentation by the major histocompatibility complex (MHC) molecules. NK cell activity and functions are controlled by a considerable number of cell surface receptors, which exist in both inhibitory and activating isoforms. There are several groups of NK cell surface receptors: 1) killer immunoglobulin like receptors-KIR, 2) C-type lectin receptors, 3) natural citotoxicity receptors-NCR and 4) Toll-like receptors-TLR. Functions of nk receptors: Defining the biology of NK cell surface receptors has contributed to the concept of the manner how NK cells selectively recognize and lyse tumor and virally infected cells while sparing normal cells. Further, identification of NK receptor ligands and their expression on the normal and transformed cells has led to the development of clinical approaches to manipulating receptor/ligand interactions that showed clinical benefit. NK cells are the first lymphocyte subset that reconstitute the peripheral blood following allogeneic HSCT and multiple roles for alloreactive donor NK cells have been demonstrated, in diminishing Graft vs. Host Disease (GvHD) through selective killing recipient dendritic cells, prevention of graft rejection by killing recipient T cells and participation in Graft vs. Leukaemia (GvL) effect through destruction of residual host tumor cells. Conclusion: Besides their role in HSCT, NK cell receptors have an important clinical relevance that reflects from the fact that they play a crucial role in the development of some diseases as well as in possibilities of managing all NK receptors through selective expansion and usage of NK cells in cancer immunotherapy.
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Although antioxidant systems help control the level of reactive oxygen species they may be overwhelmed during periods of oxidative stress. Evidence suggests that oxidative stress components as well as inflammatory mediators may be involved in the pathogenesis of vascular disorders, where localized markers of oxidative damage have been found. In this regard we investigated the putative antioxidant and anti-inflammatory effects of blueberry and cranberry anthocyanins and hydroxycinnamic acids against H2O2 and TNFα induced damage to human microvascular endothelial cells. Polyphenols from both berries were able to localize into endothelial cells subsequently reducing endothelial cells vulnerability to increased oxidative stress at both the membrane and cytosol level. Furthermore, berry polyphenols also reduced TNFα induced up-regulation of various inflammatory mediators (IL-8, MCP-1 and ICAM-1) involved in the recruitment of leukocytes to sites of damage or inflammation along the endothelium. In conclusion, polyphenols isolated from both blueberry and cranberry were able to afford protection to endothelial cells against stressor induced up-regulation of oxidative and inflammatory insults. This may have beneficial actions against the initiation and development of vascular diseases and be a contributing factor in the reduction of age-related deficits in neurological impairments previously reported by us.
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Cardiovascular disease is characterized by enhanced oxidative stress in the vascular wall, heart, kidney, and brain. Epidemiological evidence suggests that antioxidants, including vitamins C and E, α-carotene, and β-carotene, may be therapeutic; however, interventional trials of antioxidants have provided mixed results, with some showing deleterious consequences. It is thus crucial that we consider the implications of trial design and execution, and further investigation of cellular pro-and antioxidant mechanisms is critical. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and mineralocorticoid receptor blockers reduce the generation of reactive oxygen species, in experimental models as well as in humans, and have demonstrated beneficial cardiovascular effects. Polyphenols and antioxidants contained in foods and beverages may also be cardioprotective. Recent studies suggest that the judicious development of antioxidant agents may provide an effective approach to quench oxidative stress in tissues and improve cardiovascular health.
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Reduced bioavailability of endogenous nitric oxide (NO) is a central pathophysiological event in hypertension and other cardiovascular diseases. Recently, it was demonstrated that inorganic nitrate from dietary sources is converted in vivo to form nitrite, NO, and other bioactive nitrogen oxides. We tested the hypothesis that dietary inorganic nitrate supplementation may have therapeutic effects in a model of renal and cardiovascular disease. Sprague-Dawley rats subjected to unilateral nephrectomy and chronic high-salt diet from 3 weeks of age developed hypertension, cardiac hypertrophy and fibrosis, proteinuria, and histological as well as biochemical signs of renal damage and oxidative stress. Simultaneous nitrate treatment (0.1 or 1 mmol nitrate kg⁻¹ day⁻¹), with the lower dose resembling the nitrate content of a diet rich in vegetables, attenuated hypertension dose-dependently with no signs of tolerance. Nitrate treatment almost completely prevented proteinuria and histological signs of renal injury, and the cardiac hypertrophy and fibrosis were attenuated. Mechanistically, dietary nitrate restored the tissue levels of bioactive nitrogen oxides and reduced the levels of oxidative stress markers in plasma (malondialdehyde) and urine (Class VI F2-isoprostanes and 8-hydroxy-2-deoxyguanosine). In addition, the increased circulating and urinary levels of dimethylarginines (ADMA and SDMA) in the hypertensive rats were normalized by nitrate supplementation. Dietary inorganic nitrate is strongly protective in this model of renal and cardiovascular disease. Future studies will reveal if nitrate contributes to the well-known cardioprotective effects of a diet rich in vegetables.