|
|
Recent Longevity News for the week ending
10/29/14:
Dietary
cocoa flavanols reverse age-related memory decline in mice - Science Daily,
10/26/14 - "Most methods of processing
cocoa remove many of the flavanols found in
the raw plant ... 37 healthy volunteers, ages 50 to 69, were randomized to
receive either a high-flavanol diet (900 mg of flavanols a day) or a
low-flavanol diet (10 mg of flavanols a day) for three months. Brain imaging and
memory tests were administered to each
participant before and after the study ... When we imaged our research subjects'
brains, we found noticeable improvements in the function of the dentate gyrus in
those who consumed the high-cocoa-flavanol drink ... The high-flavanol group
also performed significantly better on the memory test ... If a participant had
the memory of a typical 60-year-old at the beginning of the study, after three
months that person on average had the memory of a typical 30- or 40-year-old ...
The precise formulation used in the CUMC study has also been shown to improve
cardiovascular health ... the product used in the study is not the same as
chocolate, and they caution against an increase in chocolate consumption in an
attempt to gain this effect" - See
Garden of Life, Radical Fruits Antioxidant Complex at Amazon.com.
Why Stretching Is a Waste of Time for Runners - ABC News, 10/23/14 -
"runners who stretched were just as likely to be plagued
with injuries as those who never bothered. Another study that looked at more
than 1,500 serious male marathoners found that those who stretched on a regular
basis -- whether before or after a run -- actually had 33 percent more injuries
than those who didn't, even taking things like age and average weekly mileage
into account ... Even worse, some studies suggest that stretching may be
detrimental to performance" - Note: I've read studies as far back
as the '70's saying this but I still see people doing it.
Low Testosterone in
Diabetic Men Tied to Vascular Risk - Medscape, 10/22/14 -
"A total of 79 men had normal total
testosterone (> 12.1 nmol/L, or > 3.5 ng/mL),
and 36 men had low total testosterone (< 12.1 nmol/L, or < 3.5 ng/mL) — based on
International Society of Andrology cutoffs ... More patients with low vs normal
testosterone levels had a CIMT of 0.1 cm or greater (80% vs 39%),
atherosclerotic plaques (68.5% vs 44.8%), and endothelial dysfunction (80.5% vs
42.3%). Low testosterone levels were also associated with higher CRP levels"
Anti-inflammatories May
Help Ease Depression - Medscape, 10/21/14 - "Results
of a meta-analysis show that the adjunctive use of
NSAIDs was associated with improved antidepressant treatment response
without an increased risk for adverse effects. In particular, add-on treatment
with celecoxib (Celebrex, GD Searle LLC) improved antidepressant effects,
remission, and response"
Abstracts from this week:
n-3 PUFA
Induce Microvascular Protective Changes During Ischemia/Reperfusion -
Lipids. 2014 Oct 26 - "we may conclude that consumption
of n-3 polyunsaturated fatty acids, especially in
the triacylglycerol form, could be a promising therapy to prevent microvascular
damage induced by ischemia/reperfusion and its
consequent clinical sequelae" - See
fish oil supplements at Amazon.com.
Do
Environmental Factors Modify the Genetic Risk of Prostate Cancer? - Cancer
Epidemiol Biomarkers Prev. 2014 Oct 23 - "This study
suggests that selenium supplements may reduce
genetic risk of advanced PCa, while aspirin,
ibuprofen, and vegetables may reduce genetic risk of nonadvanced PCa" -
See
se-methyl l-selenocysteine at Amazon.com.
Total
testosterone is the most valuable indicator of metabolic syndrome among various
testosterone values in middle-aged Japanese men - Endocr J. 2014 Oct 23 -
"TT and
SHBG were significantly lower in men with
MetS than in men without MetS. All testosterone
values gradually decreased as the number of MetS components increased"
Effects of
Docosahexaenoic Acid on the Endothelial Function in Patients with Coronary
Artery Disease - J Atheroscler Thromb. 2014 Oct 24 -
"The serum level of DHA is associated with the endothelial function evaluated
according to the FMD in patients with CAD, thus suggesting that a low serum
level of DHA may be a predictive biomarker for endothelial dysfunction" -
See
docosahexaenoic acid at Amazon.com.
The effect of vitamin D supplementation on serum lipids in postmenopausal women
with diabetes: A randomized controlled trial - j.clnu.2014.10.002 -
"randomly assigned in a double-blind manner to 1 of 2
groups taking a daily tablet for 6 months: a group consuming 4000 IU tablets of
a vitamin D supplement (vitamin D group n = 52)
or a group consuming placebo tablets (placebo group n = 52) ... did identify a
greater decrease in serum triglycerides in
the vitamin D group. The average effect of supplementation on the treated group
was −34.24 mg/dL (P = 0.021), while the average treatment effect was −31.8 mg/dL
(P = 0.023)" - [Nutra
USA] - See
vitamin D at Amazon.com.
Dietary
supplement use and colorectal cancer risk: A systematic review and meta-analyses
of prospective cohort studies - Int J Cancer. 2014 Oct 21 -
"In total, 24 papers were included in the meta-analyses.
We observed inverse associations for colorectal cancer
risk and multivitamin (U-NU: RR=0.92; 95%CI: 0.87,0.97) and calcium supplements
(U-NU: RR=0.86; 95%CI: 0.79,0.95; H-L: RR=0.80; 95%CI: 0.70,0.92; DR: for an
increase of 100 mg/day, RR=0.96; 95%CI: 0.94,0.99)"
Inhibitory
Effects of French Pine Bark Extract, Pycnogenol® , on Alveolar Bone Resorption
and on the Osteoclast Differentiation - Phytother Res. 2014 Oct 21 -
"Pycnogenol® (PYC) ...
PYC treatment significantly inhibited osteoclast formation. Addition of PYC
(1-100 µg/ml) to purified osteoclasts culture induced cell apoptosis. These
results suggest that PYC may prevent alveolar bone resorption through its
antibacterial activity against P. gingivalis and by suppressing
osteoclastogenesis. Therefore, PYC may be useful as a therapeutic and
preventative agent for bone diseases such as
periodontitis" - See
Pycnogenol at Amazon.com.
Severe
Periodontitis Is Inversely Associated with Coffee Consumption in the Maintenance
Phase of Periodontal Treatment - Nutrients. 2014 Oct 21;6(10):4476-4490 -
"A total of 414 periodontitis
patients in the maintenance phase of periodontal treatment completed a
questionnaire including items related to coffee
intake and underwent periodontal examination ... presence of severe
periodontitis was correlated with smoking (former, OR = 1.35, p = 0.501;
current, OR = 3.98, p < 0.05), coffee consumption (≥1 cup/day, OR = 0.55, p <
0.05), number of teeth present (OR = 0.95, p < 0.05), and bleeding on probing ≥
20% (OR = 3.67, p < 0.001)"
Diet Quality
and Survival After Ovarian Cancer: Results From the Women's Health Initiative
- J Natl Cancer Inst. 2014 Oct 21;106(11) - "Overall,
higher diet quality was associated with lower all-cause mortality after
ovarian cancer (hazard ratio [HR] for
highest vs lowest tertile = 0.73"
Fish and
fatty acid consumption and the risk of hearing loss in women - Am J Clin
Nutr. 2014 Nov;100(5):1371-7 - "Data were from the
Nurses' Health Study II, a prospective cohort study ... In comparison with women
who rarely consumed fish (<1 serving/mo), the multivariable-adjusted RR for
hearing loss among women who consumed 2-4
servings of fish per week was 0.80 (95% CI: 0.74, 0.88) (P-trend < 0.001) ... In
comparison with women in the lowest quintile of intake of
long-chain omega-3 PUFAs, the
multivariable-adjusted RR for hearing loss among women in the highest quintile
was 0.85 (95% CI: 0.80, 0.91) and among women in the highest decile was 0.78
(95% CI: 0.72, 0.85) (P-trend < 0.001)" - See
fish oil supplements at Amazon.com.
Serum
25-hydroxyvitamin D, mortality, and incident cardiovascular disease, respiratory
disease, cancers, and fractures: a 13-y prospective population study - Am J
Clin Nutr. 2014 Nov;100(5):1361-70 - "Participants were
categorized into 5 groups according to baseline serum concentrations of total
25(OH)D <30, 30 to <50, 50 to <70, 70 to <90, and ≥90 nmol/L ... The age-, sex-,
and month-adjusted HRs (95% CIs) for all-cause
mortality (2776 deaths) for men and women by increasing
vitamin D category were 1, 0.84 (0.74, 0.94),
0.72 (0.63, 0.81), 0.71 (0.62, 0.82), and 0.66 (0.55, 0.79)" - See
vitamin D at Amazon.com.
Vitamin D
deficiency is associated with inflammatory cytokine concentrations in patients
with diabetic foot infection - Br J Nutr. 2014 Oct 21;:1-6 -
"As cytokine regulation
plays a significant role in infection and wound-healing processes, the present
study aimed to evaluate the association between
vitamin D status and inflammatory cytokine profiles in patients with
diabetic foot infection ... severe vitamin D deficiency is associated with
elevated inflammatory cytokine concentrations in diabetic patients, particularly
in those with foot infection" - See
vitamin D at Amazon.com.
Resveratrol
Based Oral Nutritional Supplement Produces Long-Term Beneficial Effects on
Structure and Visual Function in Human Patients - Nutrients. 2014 Oct
17;6(10):4404-4420 - "Longevinex® (L/RV) is a low dose
hormetic over-the-counter (OTC) oral resveratrol
(RV) based matrix of red wine solids, vitamin D3 and
inositol hexaphosphate (IP6) with established
bioavailability, safety, and short-term efficacy against the earliest signs of
human atherosclerosis, murine cardiac reperfusion injury, clinical retinal
neovascularization, and stem cell survival ... We observed broad bilateral
improvements in ocular structure and function over a long time period, opposite
to what might be expected due to aging and the natural progression of the
patient's pathophysiology. No side effects were observed" - See
resveratrol products at Amazon.com
and
IP-6 products at Amazon.com.
Dietary
glycaemic index and glycaemic load in relation to all-cause and cause-specific
mortality in a Japanese community: the Takayama study - Br J Nutr. 2014 Oct
20:1-8 - "Diets with a high
glycaemic index (GI) or glycaemic load (GL) have been hypothesised to
increase the risk of diabetes, CVD and some cancers. In the present study, the
associations of dietary GI and GL with the risk of all-cause and cause-specific
mortality were prospectively examined in a general population in Japan, where
white rice is the main contributor of dietary GI and GL ... Dietary intake was
assessed using a validated FFQ ... In men, dietary GI was found to be
significantly inversely associated with the risk of all-cause and non-cancer,
non-cardiovascular mortality; the hazard ratios (HR) for the highest v. lowest
quartile were 0.80 (95 % CI 0.68, 0.95) and 0.64 (95 % CI 0.49, 0.84),
respectively. Dietary GL was found to be significantly inversely associated with
the risk of all-cause, cancer, and non-cancer, non-cardiovascular mortality; the
HR for the highest v. lowest quartile were 0.71 (95 % CI 0.59, 0.86), 0.71 (95 %
CI 0.52, 0.99) and 0.64 (95 % CI 0.48, 0.87), respectively. The results obtained
for the GL derived from white rice, but not from other foods, closely mirrored
those obtained for overall GL. In women, dietary GI was found to be
significantly positively associated with the risk of cardiovascular mortality;
the HR for the highest v. lowest quartile was 1.56 (95 % CI 1.15, 2.13)"
Astaxanthin
lowers plasma TAG concentrations and increases hepatic antioxidant gene
expression in diet-induced obesity mice - Br J Nutr. 2014 Oct 20:1-8 -
"Non-alcoholic fatty
liver disease (NAFLD) is significantly associated with hyperlipidaemia and
oxidative stress. We have previously reported that astaxanthin (ASTX), a
xanthophyll carotenoid, lowers plasma total
cholesterol and TAG concentrations in apoE knockout mice ... ASTX
supplementation lowered the plasma concentrations of TAG, ALT and AST, increased
the hepatic expression of endogenous antioxidant genes, and rendered splenocytes
less sensitive to LPS stimulation. Therefore, ASTX may prevent
obesity-associated metabolic disturbances and inflammation" - See
carotenoids at Amazon.com.
Health Focus (Quercetin):
Specific Recommendations:
News & Research:
-
Antioxidant
may boost exercise endurance - msnbc.com, 6/29/09 -
"Compared with days of no supplementation, the
quercetin supplement periods were associated with a modest — nearly 4
percent — increase in maximum oxygen uptake. Quercetin was also associated
with a 13 percent increase in "ride time" before the volunteers were too
fatigued to continue"
-
Quercetin Inhibits Path to Myocardial Ischemia-Reperfusion Injury -
Medscape, 3/16/09 - "The naturally occurring flavone
quercetin inhibits mRNA and protein expression of several components
involved in the pathophysiology of myocardial ischemia-reperfusion injury in
rabbits"
-
Cranberry extracts may prevent colon cancer: Lab study - Nutra USA,
2/13/09 - "These findings are important because they
demonstrate that the F-κB signalling pathway provides a potential
mechanistic link between inflammation and cancer and that the
anti-inflammatory properties of crude cranberry extract or quercetin can be
used to modulate this pathway" - See
cranberry extract at Amazon.com.
-
Flavonoids’ heart health benefits in the blood vessels: Study - Nutra
USA, 10/10/08 - "A daily dose of quercetin or
(-)-epicatechin led to improvements in endothelial function, a key marker of
cardiovascular health" - [Abstract]
-
Substance Found In Fruits And Vegetables Reduces Likelihood Of The Flu -
Science Daily, 0/3/08 - "Mice that exercised and
took quercetin had nearly the same rate of illness as those that did not
exercise. In other words, quercetin canceled out the negative effect of
stressful exercise ... Although this study was done with mice, a recent
human study found that people who took quercetin suffered fewer illnesses
following three days of exhaustive exercise compared to those who did not"
-
Veggies, Exercise May Cut Cancer Risk - WebMD, 4/15/08 -
"People who ate quercetin-rich foods at least four
times a week, on average, were 51% less likely to have lung cancer than
those who ate none"
-
Onion compound linked to lower blood pressure - Nutra USA, 10/23/07 -
"receive a daily supplement of quercetin (730 mg,
USANA Health Sciences) or placebo for 28 days ... the hypertensives
receiving the quercitin supplement experienced reductions in systolic and
diastolic BP of seven and five mmHg, respectively, compared to placebo"
-
Chemical in Curry
May Cut Colon Cancer - WebMD, 8/2/06 -
"Each of the patients then received 480 milligrams
of curcumin and 20 milligrams of quercetin three times a day for six months
... The results showed that treatment with the curry and onion compounds
reduced the average number of polyps by 60%, and decreased their size by
50%" - See
curcumin supplements at Amazon.com and
iHerb
quercetin products.
-
Apples May Ward Off Alzheimer's Disease
- WebMD, 11/18/04 -
"The results suggest that quercetin "contributes
significantly" to the protection of brain cells from free radicals in
conditions like
Alzheimer's disease"
- Mediterranean diet
'extends life' - bbc.co.uk. 8/24/03 - "The[y]
found that quercetin, which is abundant in olive oil, has a similar effect"
-
Drinking Tea May Help Prevent Heart Attacks - Doctor's Guide, 5/9/02 -
"Drinking more tea and increasing
flavonoid intake may help primary prevention of
ischaemic heart disease ... The intake of the dietary flavonoids quercetin,
kaempferol and myricetin was significantly associated inversely with fatal
myocardial infarction only in upper tertiles of intake"
-
Quercetin Relieves Prostate Pain - Nutrition Science News, 7/01
-
Quercetin Is Promising for Chronic Prostatitis - Nutrition Science News,
4/01 - "an encouraging 59 percent of the subjects
improved"
-
Canceling Cancer: New Cancer Prevention Strategies on the Horizon -
WebMD, 3/26/01 - "Xing has shown that quercetin
blocks androgen receptors when applied to cancer cells in the laboratory ...
We are very excited by our finding that the new approach quercetin [can be
used] in the fight against prostate cancer"
-
Eating apples improves lung function - Doctor's Guide, 1/26/00 -
"Apples are high in the antioxidant flavoid quercetin. This antioxidant is
also found in onions, tea and red wine and it may be important in protecting
the lungs from the harmful effects of atmospheric pollution and cigarette
smoke"
- New Study Offers Hope
for Chronic Prostatitis Treatment
- Medscape, 1/00 -
"More than 80% of chronic prostatitis patients who
took a proprietary formulation of quercetin, a natural dietary supplement,
significantly reduced pain and improved their quality of life, according to
a new study published in the December issue of Urology"
Abstracts:
-
Multi-target
effects of Quercetin in Leukemia - Cancer Prev Res (Phila). 2014 Oct 7 -
"The antitumor activity of quercetin both in vitro and
in vivo revealed in this study, point to quercetin as an attractive antitumor
agent for hematological malignancies" - See
quercetin at Amazon.com.
-
Quercetin
prevents docetaxel-induced testicular damage in rats - Andrologia. 2014 Mar
6 - "the administration of docetaxel induced the
testicular damage (oxidative stress, testes tissue damage and sperm parameters),
and quercetin prevented docetaxel-induced testicular damage in rats" -
See
quercetin at Amazon.com.
-
Site-Specific Anticancer Effects of Dietary Flavonoid Quercetin - Nutr
Cancer. 2013 Dec 30 - "Food-derived flavonoid quercetin,
widely distributed in onions, apples, and tea, is able to inhibit growth of
various cancer cells indicating that this compound can be considered as a good
candidate for anticancer therapy. Although the exact mechanism of this action is
not thoroughly understood, behaving as antioxidant and/or prooxidant as well as
modulating different intracellular signalling cascades may all play a certain
role. Such inhibitory activity of quercetin has been shown to depend first of
all on cell lines and cancer types; however, no comprehensive site-specific
analysis of this effect has been published. In this review article, cytotoxicity
constants of quercetin measured in various human malignant cell lines of
different origin were compiled from literature and a clear cancer selective
action was demonstrated. The most sensitive malignant sites for quercetin
revealed to be cancers of blood, brain, lung, uterine, and salivary gland as
well as melanoma whereas cytotoxic activity was higher in more aggressive cells
compared to the slowly growing cells showing that the most harmful cells for the
organism are probably targeted"
-
Chemopreventive Effect of Quercetin in MNU and Testosterone Induced Prostate
Cancer of Sprague-Dawley Rats - Nutr Cancer. 2013 Dec 9 -
"male Sprague-Dawley rats were induced prostate cancer
by hormone (testosterone) and carcinogen (MNU) and simultaneously supplemented
with quercetin (200 mg/Kg body weight) thrice a week ... The study concluded
that dietary quercetin prevented MNU + T-induced prostate carcinogenesis on both
ventral and dorsolateral lobes of Sprague-Dawley rats"
-
Quercetin
prevents liver carcinogenesis by inducing cell cycle arrest, decreasing cell
proliferation and enhancing apoptosis - Mol Nutr Food Res. 2013 Oct 1 -
"Adult male Wistar rats were subjected to a two-phase
model of hepatocarcinogenesis (initiated-promoted group). Initiated-promoted
animals also received quercetin 10 and 20 mg/kg body weight (IPQ10 and IPQ20
groups, respectively). Antioxidant defenses were modified by quercetin
administration at both doses. However, only IPQ20 group showed a reduction in
number and volume of preneoplastic lesions. This group showed increased
apoptosis and a reduction in the proliferative index"
-
Chemopreventive effect of quercetin, a natural dietary flavonoid on prostate
cancer in in vivo model - Clin Nutr. 2013 Sep 3 -
"the rats were divided into four groups; Group I: control (propylene
glycol-vehicle), Group II: cancer-induced (MNU and Testosterone treated) rats,
Group III: cancer-induced + Quercetin (200 mg/kg body wt/orally) and Group IV:
Quercetin (200 mg/kg body wt) thrice a week ... Quercetin down regulates the
cell survival, proliferative and anti-apoptotic proteins thereby prevents
prostate cancer, by acting as a chemopreventive agent in preclinical model"
-
Quercetin
Protects Mouse Brain against Lead-induced Neurotoxicity - J Agric Food Chem.
2013 Jul 15 - "Mice were exposed to lead acetate (20
mg/kg body weight/day) intragastrically with or without QE (15 and 30 mg/kg body
weight/day) co-administration for three months. Our data showed that QE
significantly prevented Pb-induced neurotoxicity in a dose-dependent manner. In
exploring the underlying mechanisms of QE action, we found QE administration
decreased Pb contents in blood (13.2%, 19.1%) and brain (17.1%, 20.0%). QE
markedly increased NO production (39.1%, 61.1%) and PKA activity (51.0%, 57.8%)
in brains of Pb-treated mice. Additionally, QE remarkably suppressed Pb-induced
oxidative stress in mouse brain. Western blot analysis showed that QE increased
the phosphorylations of Akt, CaMKII nNOS, eNOS and CREB in brains of Pb-treated
mice" - See
quercetin at Amazon.com.
-
Quercetin
Potentiates Apoptosis by Inhibiting Nuclear Factor-kappaB Signaling in H460 Lung
Cancer Cells - Biol Pharm Bull. 2013;36(6):944-951 -
"The herbal flavonoid quercetin inhibits the growth of various cancer cells, but
how it affects human cancer cells, particularly lung cancer cells, is unclear
... Taken together, these findings suggest that quercetin may be useful in the
prevention and therapy of NSCLC"
-
Resveratrol
and Quercetin in Combination Have Anticancer Activity in Colon Cancer Cells and
Repress Oncogenic microRNA-27a - Nutr Cancer. 2013 Apr;65(3):494-504 -
"Resveratrol and quercetin (RQ) in combination (1:1
ratio) previously inhibited growth in human leukemia cells. This study
investigated the anticancer activity of the same mixture in HT-29 colon cancer
cells. RQ decreased the generation of reactive oxygen species (ROS) by up to
2.25-fold and increased the antioxidant capacity by up to 3-fold in HT-29 cells
(3.8-60 μg/mL), whereas IC50 values for viability were 18.13, 18.73, and 11.85
μg/mL, respectively. RQ also induced caspase-3-cleavage (2-fold) and increased
PARP cleavage. Specificity protein (Sp) transcription factors are overexpressed
in colon and other cancers and regulate genes required for cell proliferation
survival and angiogenesis" - See
resveratrol products at Amazon.com
and
quercetin at Amazon.com.
-
Quercetin
Induces Apoptosis via Mitochondrial Pathway in KB and KBv200 cells - J Agric
Food Chem. 2013 Feb 14 - "In this study, anticancer
activities of six compounds of flavonoids were investigated in human epidermoid
carcinoma KB and KBv200 cells. Among these compounds, quercetin and acacetin
showed strong inhibition of cell growth in KB and KBv200 cells"
-
Dietary fat
increases quercetin bioavailability in overweight adults - Mol Nutr Food
Res. 2013 Jan 15 - "Epidemiologic evidence supports that
dietary quercetin reduces cardiovascular disease (CVD) risk, but its oral
bioavailability is paradoxically low. The aim of this study was to determine
whether dietary fat would improve quercetin bioavailability in adults at high
risk for CVD and to assess lipid-mediated micellarization of quercetin in vitro
... In a randomized, cross-over study, overweight/obese men and postmenopausal
women (n = 4 M/5 F; 55.9 +/- 2.1 years; 30.8 +/- 1.4 kg/m(2) ) ingested 1095 mg
of quercetin aglycone with a standardized breakfast that was fat-free (<0.5 g),
low-fat (4.0 g), or high-fat (15.4 g) ... Compared to the fat-free trial, plasma
quercetin maximum concentration (C(max) ), and area under curve (AUC(0-24 h) )
increased (p < 0.05) by 45 and 32%, respectively, during the high-fat trial"
-
Protective
Effects of Quercetin on Streptozotocin-induced Diabetic Nephropathy in Rats
- Phytother Res. 2012 Dec 27 - "Diabetic nephropathy
(DN) is an important microvascular complication and one of the main causes of
end-stage renal disease. In this study, we examined the protective effects of
quercetin on DN in streptozotocin-induced diabetic rats ... Compared with the
levels in the DN group, quercetin decreased the levels of fasting blood glucose,
creatinine, blood urea nitrogen, and urine protein, and the intensity of
oxidative stress decreased significantly. Quercetin significantly inhibited the
expression of advanced glycosylation end products, collagen IV, laminin,
connective tissue growth factor, Smad 2/3, and transforming growth factor-β(1)
mRNA. Moreover, quercetin was observed to inhibit proliferation of mesangial
cells and decrease thickness of glomerular basement membrane. Those results
suggest that quercetin has protective effects on several pharmacological targets
in the progress of DN and is a potential drug for the prevention of early DN"
-
Quercetin
protects against pulmonary oxidant stress via heme oxygenase-1 induction in lung
epithelial cells - Biochem Biophys Res Commun. 2011 Nov 25 -
"In the present study, we showed that quercetin
increased the levels of heme oxygenase (HO)-1 expression and protected against
hydroxy peroxide (H(2)O(2))-induced cytotoxicity in lung epithelial cell lines.
Quercetin suppressed H(2)O(2)-induced apoptotic events, including hypodiploid
cells, activation of caspase 3 enzyme activity and lactate dehydrogenase
release. This cytoprotective effect was attenuated by the addition of the HO
inhibitor, tin protoporphyrin IX. In addition, the end products of heme
metabolites catalyzed by HO-1, carbon monoxide and bilirubin, protect against
H(2)O(2)-induced cytotoxicity in LA-4 cells. Quercetin may well be one of the
promising substances to attenuate oxidative epithelial cell injury in lung
inflammation"
-
Anti-inflammatory, anti-proliferative and anti-atherosclerotic effects of
quercetin in human in vitro and in vivo models - Atherosclerosis. 2011 May 5
- "In cultured human endothelial cells, quercetin
protected against H(2)O(2)-induced lipid peroxidation and reduced the
cytokine-induced cell-surface expression of VCAM-1 and E-selectin. Quercetin
also reduced the transcriptional activity of NFκB in human hepatocytes. In human
CRP transgenic mice (quercetin plasma concentration: 12.9+/-1.3μM), quercetin
quenched IL1β-induced CRP expression, as did sodium salicylate. In ApoE*3Leiden
mice, quercetin (plasma concentration: 19.3+/-8.3μM) significantly attenuated
atherosclerosis by 40% (sodium salicylate by 86%). Quercetin did not affect
atherogenic plasma lipids or lipoproteins but it significantly lowered the
circulating inflammatory risk factors SAA and fibrinogen. Combined histological
and microarray analysis of aortas revealed that quercetin affected vascular cell
proliferation thereby reducing atherosclerotic lesion growth. Quercetin also
reduced the gene expression of specific factors implicated in local vascular
inflammation including IL-1R, Ccl8, IKK, and STAT3 ...Quercetin reduces the
expression of human CRP and cardiovascular risk factors (SAA, fibrinogen) in
mice in vivo. These systemic effects together with local anti-proliferative and
anti-inflammatory effects in the aorta may contribute to the attenuation of
atherosclerosis"
-
Quercetin's
Effects on Intestinal Polyp Multiplicity and Macrophage Number in the Apc(Min/+)
Mouse - Nutr Cancer. 2011 Mar 1:1 - "Numerous in
vitro studies argue for quercetin's chemopreventive potential in colon cancer;
however, experimental studies in rodents are limited. Macrophages play a role in
tumorigenesis, but the effects of quercetin on macrophage infiltration in colon
cancer is unknown. We examined the effects of quercetin on intestinal polyp
multiplicity and macrophage number in Apc(Min/+) mice ... These data suggest
that quercetin can reduce polyp number and size distribution in the Apc(Min/+)
mouse and that these effects may be related to a reduction in macrophage
infiltration"
-
The
Flavonoid Quercetin Modulates the Hallmark Capabilities of Hamster Buccal Pouch
Tumors - Nutr Cancer. 2011 Feb 2:1 -
"Epidemiological studies have consistently demonstrated the protective effects
of dietary phytochemicals against cancer risk. Quercetin, a ubiquitous dietary
flavonoid, has attracted considerable attention owing to its potent antioxidant
and antiproliferative activities ... Simultaneous administration of quercetin to
DMBA-painted hamsters reduced tumor incidence and tumor burden, while
posttreatment of quercetin resulted in a significant tumor growth delay. In
addition, quercetin administration induced cell cycle arrest and apoptosis and
blocked invasion and angiogenesis. We found a positive correlation between the
inhibition of HDAC-1 and DNMT1 by quercetin and its anticancer properties. A
dietary phytochemical such as quercetin that modulates a plethora of molecules
offers promise as an ideal candidate for multitargeted cancer prevention and
therapy"
-
Quercetin is
equally or more effective than resveratrol in attenuating tumor necrosis
factor-{alpha}-mediated inflammation and insulin resistance in primary human
adipocytes - Am J Clin Nutr. 2010 Oct 13 - "These
data suggest that quercetin is equally or more effective than trans-RSV in
attenuating TNF-α-mediated inflammation and insulin resistance in primary human
adipocytes"
-
Dietary flavonoid intake and colorectal cancer: a case-control study - Br J
Nutr. 2009 Sep 7:1-8 - "We concluded that flavonols,
specifically quercetin, obtained from non-tea components of the diet may be
linked with reduced risk of developing colon cancer"
-
Inhibition
of UVA and UVB radiation-induced lipid oxidation by quercetin - J Agric Food
Chem. 2009 Jun 24;57(12):5301-5 - "Quercetin, which
absorbs UV radiation at 255 and 365 nm, was determined to be a stronger
inhibitor of lipid oxidation induced by UVB (3.7 radicals scavenged per
molecule) than by lipid oxidation induced by UVA (1.9 radicals scavenged per
molecule). The values for inhibition of UVB-induced lipid oxidation by quercetin
are comparable to those when 2,2'-azobis(2-amidinopropane) was used as an
oxidizing system (four radicals scavenged per molecule). The protective effect
of quercetin appears to be mainly the result of scavenging of UV-generated
radical species, although this may be decreased slightly in the UVA as a result
of its absorption at 365 nm"
-
Quercetin
inhibits fatty acid and triacylglycerol synthesis in rat-liver cells - Eur J
Clin Invest. 2009 Jun 8 - "In hepatocytes from normal
rats, the quercetin-induced decrease in both de novo fatty acid and TAG
synthesis, with a consequent reduction in VLDL-TAG formation, may represent a
potential mechanism contributing to the reported hypotriacylglycerolemic effect
of quercetin"
-
Quercetin reduces systolic blood pressure and plasma oxidised low-density
lipoprotein concentrations in overweight subjects with a high-cardiovascular
disease risk phenotype: a double-blinded, placebo-controlled cross-over study
- Br J Nutr. 2009 Apr 30:1-10 -
"Subjects were randomised to receive 150 mg
quercetin/d in a double-blinded, placebo-controlled cross-over trial with 6-week
treatment periods separated by a 5-week washout period. Mean fasting plasma
quercetin concentrations increased from 71 to 269 nmol/l (P < 0.001) during
quercetin treatment. In contrast to placebo, quercetin decreased systolic blood
pressure (SBP) by 2.6 mmHg (P < 0.01) in the entire study group, by 2.9 mmHg (P
< 0.01) in the subgroup of hypertensive subjects and by 3.7 mmHg (P < 0.001) in
the subgroup of younger adults aged 25-50 years. Quercetin decreased serum
HDL-cholesterol concentrations (P < 0.001), while total cholesterol, TAG and the
LDL:HDL-cholesterol and TAG:HDL-cholesterol ratios were unaltered. Quercetin
significantly decreased plasma concentrations of atherogenic oxidised LDL, but
did not affect TNF-alpha and C-reactive protein when compared with placebo ...
Blood parameters of liver and kidney function, haematology and serum
electrolytes did not reveal any adverse effects of quercetin. In conclusion,
quercetin reduced SBP and plasma oxidised LDL concentrations in overweight
subjects with a high-CVD risk phenotype. Our findings provide further evidence
that quercetin may provide protection against CVD"
-
Quercetin up-regulates paraoxonase 1 gene expression with
concomitant protection against LDL oxidation - Biochem Biophys
Res Commun. 2009 Jan 10 - "Compared to the
pair-fed control group, feeding quercetin (10mg/L) in the liquid
diet for 4 weeks increased (a) hepatic expression of PON1 by 35%
(p<0.01), (b) serum and liver PON1 activities by 29% (p<0.05) and
57% (p<0.01), respectively, and (c) serum homocysteine thiolactonase
(HCTL) activity by 23% (p<0.05). Correspondingly, the lag time of
low-density lipoprotein (LDL) oxidation was increased by >3-fold
(p<0.001) with plasma HDL from quercetin-fed group compared to the
HDL from control group. Our data suggest that quercetin has
antiatherogenic effect by up regulating PON1 gene expression and its
protective capacity against LDL oxidation"
-
Protective Effect of Quercetin against Gentamicin-Induced
Nephrotoxicity in Rats - Pharm Bull. 2009 Jan;32(1):61-7 -
"Gentamicin (GM) is an antibiotic widely
used in treating severe gram-negative infections. However, its
clinical use is limited by its nephrotoxicity ... Histopathological
examination of GM-treated rats revealed degenerative changes in
glomeruli and tubules. On the other hand, simultaneous
administration of quercetin plus gentamicin protected kidney tissues
against nephrotoxic effects of gentamicin as evidenced from
amelioration of histopathological changes and normalization of
kidney biochemical parameters"
-
Pure dietary flavonoids quercetin and (-)-epicatechin augment nitric
oxide products and reduce endothelin-1 acutely in healthy men -
Am J Clin Nutr. 2008 Oct;88(4):1018-25 -
"Dietary flavonoids, such as quercetin and (-)-epicatechin, can
augment nitric oxide status and reduce endothelin-1 concentrations
and may thereby improve endothelial function"
-
Serum
C-reactive protein concentrations are inversely associated with
dietary flavonoid intake in u.s. Adults - J Nutr. 2008
Apr;138(4):753-60 - "Among the flavonoid
compounds investigated, quercetin, kaempferol, malvidin, peonidin,
daidzein, and genistein had inverse associations with serum CRP
concentration"
-
Quercetin
inhibits vascular superoxide production induced by endothelin-1:
Role of NADPH oxidase, uncoupled eNOS and PKC - Atherosclerosis.
2008 Mar 16 - "Chronic administration of the
most abundant dietary flavonoid quercetin exerts antihypertensive
effects and improves endothelial function ... endothelin-1 (ET-1,
10nM). ET-1 increased the contractile response induced by
phenylephrine and reduced the relaxant responses to acetylcholine in
phenylephrine contracted intact aorta, and these effects were
prevented by co-incubation with quercetin, isorhamnetin or
chelerythrine (protein kinase C (PKC) inhibitor). This endothelial
dysfunction was also improved by superoxide dismutase (SOD),
apocynin (NADPH oxidase inhibitor) and sepiapterin
(tetrahydrobiopterin synthesis substrate). Furthermore, ET-1
increased intracellular O(2)(-) production in all layers of the
vessel, protein expression of NADPH oxidase subunit p47(phox)
without affecting p22(phox) expression and lucigenin-enhanced
chemiluminescence signal stimulated by calcium ionophore A23187. All
these changes were prevented by both quercetin and isorhamnetin.
Moreover, apocynin, endothelium denudation and N(G)-nitro-l-arginine
methylester (l-NAME, nitric oxide synthase inhibitor) suppressed the
ET-1-induced increase in A23187-stimulated O(2)(-) generation.
Moreover, quercetin but not isorhamnetin, inhibited the increased
PKC activity induced by ET-1"
-
The flavonoid
luteolin inhibits niacin-induced flush - Br J Pharmacol. 2008
Jan 28 - "Sustained release niacin
effectively lowers serum cholesterol, LDL and triglycerides, while
raising HDL. However, 75% of patients experience cutaneous warmth
and itching known as flush, leading to discontinuation.
Acetylsalicylic acid (aspirin) reduces this flush only by about 30%
... Quercetin and luteolin (4.3 mg per rat; 1000 mg per human),
administered i.p. 45 min prior to niacin, inhibited the niacin
effect by 96 and 88%, respectively. Aspirin (1.22 mg per rat; 325 mg
per human) inhibited the niacin effect by only 30%. Niacin almost
doubled plasma PGD(2) and 5-HT, but aspirin reduced only PGD(2) by
86%. In contrast, luteolin inhibited both plasma PGD(2) and 5-HT
levels by 100 and 67%, respectively"
-
Quercetin selectively inhibits bioreduction and enhances apoptosis
in melanoma cells that overexpress tyrosinase - Nutr Cancer.
2007;59(2):258-68 - "quercetin can
selectively sensitize Tyr+ expressing melanoma cells to apoptosis
and may serve as an adjuvant to chemotherapy by enhancing cell death
and interfering with GST-mediated drug resistance"
-
Quercetin reduces blood pressure in hypertensive subjects - J
Nutr. 2007 Nov;137(11):2405-11 - "730 mg
quercetin/d for 28 d vs. placebo ... reductions in (P < 0.01)
systolic (-7 +/- 2 mm Hg), diastolic (-5 +/- 2 mm Hg), and mean
arterial pressures (-5 +/- 2 mm Hg) were observed in stage 1
hypertensive patients after quercetin treatment"
-
Comparative effects of quercetin and its predominant human
metabolites on adhesion molecule expression in activated human
vascular endothelial cells - Atherosclerosis. 2007 Sep 17 -
"both quercetin and its metabolites, at
physiological concentrations, can inhibit the expression of key
molecules involved in monocyte recruitment during the early stages
of atherosclerosis"
|
|