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Effects of kiwi fruit consumption on platelet aggregation and plasma lipids in healthy human volunteers

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Fruits and vegetables have been thought to be beneficial in cardiovascular disease. The beneficial effects of fruits and vegetables may be explained by the antioxidants and other components contained therein. These nutrients may function individually or in concert to protect lipoproteins and vascular cells from oxidation, or by other mechanisms such as reducing plasma lipid levels (LDL cholesterol, triglycerides), and platelet aggregation response. Kiwi fruit which contains high amounts of vitamin C, vitamin E and polyphenols may be beneficial in cardiovascular disease; however very little is known about its cardioprotective effects. Platelets are involved in atherosclerotic disease development and the reduction of platelet activity by medications reduces the incidence and severity of disease. To this end, we evaluated whether consuming kiwi fruit modulated platelet activity and plasma lipids in human volunteers in a randomized cross-over study. We report that consuming two or three kiwi fruit per day for 28 days reduced platelet aggregation response to collagen and ADP by 18% compared with the controls (P < 0.05). In addition, consumption of kiwi fruit lowered blood triglycerides levels by 15% compared with control (P < 0.05), whereas no such effects were observed in the case of cholesterol levels. All these data indicate that consuming kiwi fruit may be beneficial in cardiovascular disease.
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Platelets
ISSN: 0953-7104 (Print) 1369-1635 (Online) Journal homepage: http://www.tandfonline.com/loi/iplt20
Effects of kiwi fruit consumption on platelet
aggregation and plasma lipids in healthy human
volunteers
Asim K. Duttaroy & Aud Jørgensen
To cite this article: Asim K. Duttaroy & Aud Jørgensen (2004) Effects of kiwi fruit consumption on
platelet aggregation and plasma lipids in healthy human volunteers, Platelets, 15:5, 287-292, DOI:
10.1080/09537100410001710290
To link to this article: http://dx.doi.org/10.1080/09537100410001710290
Published online: 07 Jul 2009.
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Citing articles: 62 View citing articles
Effects of kiwi fruit consumption on platelet
aggregation and plasma lipids in healthy human
volunteers
Asim K. Duttaroy, Aud Jørgensen
Fruits and vegetables have been thought to be beneficial in cardiovascular disease. The beneficial effects of fruits
and vegetables may be explained by the antioxidants and other components contained therein. These nutrients may
function individually or in concert to protect lipoproteins and vascular cells from oxidation, or by other mechanisms
such as reducing plasma lipid levels (LDL cholesterol, triglycerides), and platelet aggregation response. Kiwi fruit
which contains high amounts of vitamin C, vitamin E and polyphenols may be beneficial in cardiovascular disease;
however very little is known about its cardioprotective effects. Platelets are involved in atherosclerotic disease
development and the reduction of platelet activity by medications reduces the incidence and severity of disease. To
this end, we evaluated whether consuming kiwi fruit modulated platelet activity and plasma lipids in human
volunteers in a randomized cross-over study. We report that consuming two or three kiwi fruit per day for 28 days
reduced platelet aggregation response to collagen and ADP by 18% compared with the controls (P<0.05). In
addition, consumption of kiwi fruit lowered blood triglycerides levels by 15% compared with control (P<0.05),
whereas no such effects were observed in the case of cholesterol levels. All these data indicate that consuming
kiwi fruit may be beneficial in cardiovascular disease.
Introduction
Many risk factors for cardiovascular disease (CVD)
including platelet hyperactivity, high blood choles-
terol, triglycerides, obesity and diabetes are substan-
tially influenced by dietary factors. Since these risk
factors are modifiable therefore primary preventive
efforts through dietary means hold much promise.
1
High intake of fruit and vegetables is such an
important preventive measure by which the risk of
cardiovascular disease can be reduced. The American
Heart Association and other national agencies
recommend a diet that includes 5 servings of fruit
and vegetables daily.
2,3
These recommendations are
based primarily on the studies indicate that fruit and
vegetable intake may reduce CVD risk through the
beneficial combinations of micronutrients, antioxi-
dants, phytochemicals, and fiber in fruits and
vegetables.
4–7
A decreased oxidative modification of
LDL may be one of the mechanisms by which fruits
and vegetables reduce the risk of CVD and athero-
sclerotic progression. However, hyperactivity of
platelets, and their adhesion and aggregation at the
site of injury in atherosclerotic vessel walls, is also
critically important in the pathogenesis of CVD.
8–10
There is also an increasing evidence that acute clinical
manifestations of coronary atherosclerotic disease
are caused by plaque disruption and subsequent
platelet–thrombus formation.
11–13
Coronary athero-
sclerotic lesions may appear in early life and, towards
the end of the second decade of life, asymptomatic
atherosclerotic lesions are present in most people
living in industrialised societies.
12,14
Therefore, plate-
let activity may play a major role in the development
as well as in the stability of atherosclerotic plaques.
In support of the pathophysiological role of platelets,
platelet inhibitory drugs such as aspirin reduce the
incidence of myocardial infarction, stroke and death
from CVD in secondary prevention trials.
15–18
Flavonoids are polyphenolic compounds, widely
distributed in fruit and vegetables, many of which
have antioxidant as well as anti-thrombotic proper-
ties.
19–22
Certain polyphenols have been shown to be
inhibitory to platelet aggregation than others, and
Asim K. Duttaroy, Aud Jørgensen, Department of Nutrition,
Faculty of Medicine, University of Oslo, Oslo, Norway.
Correspondence to: Professor Asim K. Duttaroy, Department of
Nutrition, University of Oslo, P.O. Box 1046 Blindern, N-0316
Oslo, Norway. Tel.: þ47-22-85-15-47; Fax: þ47-22-85-13-41;
E-mail: a.k.duttaroy@medisin.uio.no
Platelets (August 2004) 15(5), 287–292
ISSN 0953-7104 print/ISSN 1369-1635 online/04/050287-6 ß2004 Taylor & Francis Ltd
DOI: 10.1080/09537100410001710290
consequently dietary studies involving flavonoids
on anti-platelet effects are not conclusive.
23–25
The
difference in platelet inhibitory effects among poly-
phenols could be due to several reasons. Variations in
digestion, absorption, and hepatic processing may
limit the bioavailability of these compounds. It is also
possible that compounds other than the polyphenols
may be responsible for the platelet inhibitory activity.
We recently examined the anti-platelet activity of
several fruits and this activity was not related to the
antioxidants potential of fruits.
9,26
Despite the fact
that kiwi fruit contain very significant amounts of
antioxidants such as polyphenols and vitamins C and
E,
27,28
it was not included in the study. Recently it
has been shown that kiwi fruit provide a dual
protection against oxidative DNA damage, enhan-
cing antioxidant levels and stimulating DNA repair
and may be beneficial in cancer;
29
however, no
information is available on the effects of kiwi fruit
on platelet activity and plasma lipids, these two
important risk factors of CVD, in human volunteers.
In this paper we report that consuming of two or
three kiwi fruit per day for 28 days significantly
reduced platelet aggregation in human volunteers in
a randomized cross-over design. Moreover, plasma
triglycerides levels were also reduced in these
volunteers. Our study indicates that consuming kiwi
fruit (two or three per day) may be beneficial in CVD.
Materials and methods
Materials
Collagen, ADP and arachidonic acid were obtained
from Chrono-Log (Havertown, USA). Uric acid,
ascorbic acid, EDTA, acetic acid, sodium hydroxide,
metaphosphoric acid and phosphate-buffered saline
(PBS) tablets were obtained from Sigma (Poole, UK).
All other reagents used were of analytical grade
quality.
Subjects
Thirty (12 males and 18 females) healthy volunteers
took part in this study. Volunteers were aged 20–51
years and their mean BMI was 22.43 0.52 kg/m
2
.
The volunteers were recruited by means of adver-
tisements at the Institute for Nutrition Research,
University of Oslo, Oslo, Norway. Volunteers were
requested to maintain normal diet during the trial.
Subjects were allocated randomly to two groups
(n¼15), each of which was given different order of
kiwi fruit doses. Group A took two kiwi fruit per day
in the first period and three kiwi fruit per day in the
second period, whereas group B took two and three
kiwi fruit per day. Each volunteer consumed two and
three kiwi fruit per day for successive 28-day periods
separated by at least 2-week wash-out periods. The
study protocol was approved by the Ethical
Committee of Ulleva
˚l University Hospital, Oslo.
Healthy subjects were recruited after assessment of
their medical and dietary history. Exclusion criteria
were the presence of overt vascular, haematological
or respiratory disease, hypertension, infection, fre-
quent consumption of drugs which affect platelet
function (e.g., aspirin, paracetamol, ibuprofen, ste-
roid, habitual consumption of omega-3 fatty acid
supplements).
Preparation of kiwi fruit extract
In order to investigate the effects of kiwi fruit extract
on human platelet aggregation in vitro. Extracts
consisting of 100% fruit juice were freshly prepared
on the day of the assay from kiwi fruit. To prepare
100% fruit juice, the fruits were peeled and the pulp
after being weighed was homogenised. The resulting
homogenate was centrifuged at 3000 gfor 10 min.
The supernatant was collected and the pH was
adjusted to 7.4 with sodium hydroxide. The pH-
adjusted kiwi fruit extract (KFE) was then used for
in vitro platelet aggregation experiments.
Platelet aggregation study
Overnight fasted blood was collected through silico-
nized needles into plastic syringes: coagulation was
prevented by mixing 9 vol of blood with 1 vol sodium
citrate (final concentration, 13 mM). Platelet-rich
plasma (PRP) was obtained by centrifugation of
citriated blood for 15 min at 180 g. The supernatant
platelet-rich plasma (2–3 10
8
cells/ml) was collected
and used for platelet aggregation.
24
Platelet aggregation was monitored on a platelet
aggregometer (Chrono-Log) at a constant stirring
speed of 1000 rpm at 37C, as described before.
24
The
aggregating agents used were ADP (4 and 8 mM),
and collagen (4 and 8 mg/ml). Platelet aggregation
was followed over 10 min. Platelet aggregation was
performed within 2 h after the blood was taken.
Platelet aggregation is expressed as the area under the
curve. To determine the effect of KFE on platelet
aggregation in vitro, PRP (450 ml) was incubated with
50 ml of KFE for 15 min at 37C prior to the addition
of an aggregating agent. Since maximal amplitude
of aggregation of PRP was obtained with either 4 mg/
ml collagen, 8 mM ADP, and 500 mg/ml arachidonic
acid, these concentrations of agonists were used
and aggregation was followed as described above.
Controls were run in parallel replacing fruit extract
with 50 ml of PBS. Inhibition of platelet aggregation is
expressed as the decrease in the area under the curve
compared with the control.
In order to determine the effects of consumption
of kiwi fruit on platelet aggregation response in
human volunteers, blood samples were taken at
study entry (day 0), and after day 28 of fruit con-
sumption, between 08:00 and 10:00 h after an over-
night fast. PRP was prepared for platelet aggregation
experiments as described before.
288 KIWI FRUIT CONSUMPTION
Determination of plasma vitamin C
Blood was collected in heparin on ice and was
centrifuged at 2000 gfor 10 min at 4C. Then 600 ml
of plasma were mixed with 600 ml of 10% metaphos-
phoric acid in a tube and was snap frozen The
samples were stored at 80C until required for
determination of total vitamin C concentration
(vitamin C and dehydroascorbic acid) by HPLC, as
published before.
30
Ferric reducing/antioxidant power (FRAP) assay
The FRAP assay was performed according to Benzie
and Strain (1997).
31
The FRAP assay was used to
measure the concentration of total antioxidants in
plasma using Technicon RA 1000 system (Technicon
Instruments Corporation, New York, USA). An
intense blue colour with absorption maximum at
600 nm was measured.
Determination of plasma lipids
Plasma triglycerides, HDL and total cholesterol
concentrations were determined using reagents from
Genzyme diagnostics (UK) following the protocol.
LDL-cholesterol was calculated using the Friedwald
formula.
32
Statistical analysis
Results are presented as the mean SEM. Results were
analysed by the Student’s t-test. Values for the area
under the curve for platelet aggregation in the absence
and in the presence of different concentrations of
fruit extract were evaluated by a computer-assisted
programme. Other statistical analyses were per-
formed using ANOVA where appropriate, values
were considered to be significantly different when
P<0.05.
Results
Effects of kiwi fruit extract on human platelet
aggregation in vitro
One hundred percent kiwi fruit extract (KFE) (w/v)
was used in this study. Incubation of KFE (expressed
as weight of pulp used to prepare KFE) inhibited
ADP-induced platelet aggregation in a dose-
dependent manner (Figure 1). ADP-induced aggrega-
tion was inhibited by 11% with 5 mg KFE, 54% with
10 mg KFE, and 96% with 20 mg KFE, compared
with controls. KFE also inhibited collagen-induced
platelet aggregation, however, the level of inhibition
was lower with the 5- and 10-mg KFE incubations
compared with those observed with ADP-induced
platelet aggregation (Table 1). Inhibition of arachi-
donic acid-induced platelet aggregation exhibited a
very different profile with only 32% inhibition at the
highest KFE level (20 mg) tested, and nothing at all at
the lower concentrations of KFE. The IC
50
(mini-
mum concentration required for 50% inhibition of
platelet aggregation induced by ADP in 500 ml PRP)
of KFE extract was around 10 mg KFE. The KFE
extract inhibited both collagen- and ADP-induced
platelet aggregation to a greater extent, whereas
it had very little inhibitory effects on arachidonic
acid-induced aggregation.
Figure 1. Effect of different amounts of kiwi fruit extracts on platelet aggregation by ADP in vitro. PRP (450 ml) was incubated with
different amounts (0, 5, 10, and 20 mg) of kiwi fruit extract for 15 min at 37C prior to the addition of ADP (8 mM). For details, please see
Materials and methods. (A) Control; (B) 5 mg KFE; (C) 10 mg KFE; and (D) 20 mg KFE.
PLATELETS 289
Effects of consumption of kiwi fruit on plasma
antioxidants in human volunteers
Of these 30 subjects, all except two volunteers
completed the two phases of kiwi fruit consumption.
During the supplementation period no significant
change in their mean BMI was observed. The kiwi
fruit were well tolerated without any adverse effect.
Dietary antioxidants (antioxidant levels, and total
vitamin C) were measured in plasma before and after
the trial period. Figure 2 shows that the plasma levels
of FRAP increased significantly after two or three
kiwi fruit per day. FRAP levels were increased very
significantly in both the groups after consuming
fruit (two or three kiwi fruit per day) (P<0.01),
although no statistically significant differences
between these two groups were observed. Similar to
FRAP values, plasma vitamin C levels in these
volunteers were also increased significantly, increas-
ing from 65.92 9.0 mM (day 0) to 102 23.1 mM
(day 28) (P<0.01) and from 68 15.2 mMto
92.38 14.7 mM(P<0.01) after consuming two and
three kiwi fruit per day, respectively.
Platelet aggregation
Table 2 shows the platelet aggregation response to
different concentrations of ADP and collagen at day
0 and at 28 days after consuming two or three kiwi
fruit per day. Platelet response to both low and high
concentrations of ADP or collagen was inhibited by
kiwi fruit consumption. Consuming two kiwi fruit
inhibited ADP-induced platelet aggregation signifi-
cantly (18% in case of 4 mM ADP and 15% in case of
8mM ADP compared with those at day 0 (P<0.05).
Similar reduction in platelet aggregation in response
to collagen was observed when volunteers consumed
two or three kiwi fruit per day for 28 days (Table 2).
After the wash out period (minimum 2 weeks) platelet
aggregation response returned to the base line level
(day 0).
Plasma lipids
Table 3 shows the values of plasma concentrations of
total cholesterol, HDL, LDL, and triglycerides at day
0 and day 28. Mean total cholesterol, LDL, and HDL
cholesterol values in all groups were unchanged from
days 0 to 28 in both groups, whereas triglyceride
concentrations were significantly lowered on day 28
(1.16 0.45 mmol/l at day 0 vs. 0.87 0.29 mmol/l,
P<0.05, at day 28 and 1.19 0.35 vs.0.84
0.35 mmol/l, P<0.05, in the case where volunteers
consumed two and three kiwi fruit per day, respec-
tively), compared with those on day 0 in both groups
(P<0.05). After the wash-out period (minimum 2
weeks), plasma triglyceride concentrations returned
to the base line level.
Discussion
The kiwi fruit extracts inhibited both ADP and
collagen-induced platelet aggregation in vitro, but not
arachidonic acid-induced aggregation, indicating that
the thromboxane pathway does not appear to be
involved, as we observed in the case of tomato
extract.
26
This is quite different than that of aspirin’s
mode of action in platelets. Aspirin’s anti-platelet
action involves inhibition of the cyclooxygenase
enzyme in platelets, leading to a decreased formation
of prostaglandin G
2
, a precursor of TxA
2
.
17,18
This
blocks the formation of TxA
2
, a platelet aggregation
agonist. Since kiwi fruit extract does not inhibit the
Figure 2. Effect of consuming kiwi fruit on plasma FRAP
values in volunteers. FRAP was measured in the plasma of
volunteers at day 0 and after consuming two kiwi fruit per day for
28 days. For details, please see Materials and methods.
Table 2. Effect of kiwi fruit consumption on platelet aggregation
Agents Two kiwi
fruit per day
Three kiwi
fruit per day
Day 0 Day 28 Day 0 Day 28
% Aggregation
ADP, 4 mM703.2 53 3.2* 69 1.8 55 2.1*
ADP, 8 mM693.1 55 4.1* 68 2.3 52 3.2*
Collagen, 4 mg/ml 68 4.2 52 2.3* 67 3.1 53 3.1*
Collagen, 8 mg/ml 70 3.9 51 4.3* 70 2.2 50 3.5*
For details please see Materials and methods, *P< 0.05.
Table 1. Mean percentage inhibition of platelet aggregation in
vitro by kiwi fruit extracts induced by three different aggregating
agents
Kiwi fruit extract
(mg)
Inhibition of platelet aggregation (%)
Arachidonic
acid (500 mg/ml)
Collagen
(2 mg/l)
ADP (8 mM)
5 0 0.53 0.21 11 4.3
10 0 18 4.5 54 12
20 32 89611 96 14
For details please see Materials and methods.
290 KIWI FRUIT CONSUMPTION
thromboxane pathway, it is possible that the mode of
action is upstream of platelet activation/aggregation
processes. At present we do not know the nature of
the anti-platelet factors in kiwi fruit.
This study was, therefore, designed to assess the
effects of kiwi fruit consumption on the cardiovas-
cular risk profiles in healthy volunteers. Kiwi fruit
consumption increased plasma antioxidants and
vitamin C levels in these volunteers as expected.
Consuming two or three kiwi fruit reduced platelet
aggregation to a similar extent. In addition, con-
sumption of kiwi fruit reduced plasma triglyceride
levels without affecting cholesterol levels in these
volunteers. There were no correlations between
individual changes in platelet aggregation response
and plasma lipids and vitamin C values. In addition,
the magnitude of these effects of kiwi fruit is not
related to the number of kiwi fruit consumed. We do
not have any explanation for this. The inhibitory
effects on platelet aggregation response and lowering
effects on plasma triglyceride levels of kiwi fruit
disappeared during the wash-out period. This indi-
cates that the effects of kiwi fruit on platelets and
plasma lipids are reversible. We restricted our study
with relatively small number of kiwi fruit (two, or
three), as consuming larger number of fruits is known
to have laxative effect. However, further work is
necessary to determine the structure and mechanism
of action of the active principles in kiwi fruit
responsible for lowering platelet aggregation
response as well as plasma triglycerides in humans.
Epidemiological studies as well as laboratory
experiments have provided very strong evidence
that fruits and vegetables and specific antioxidants
are beneficial for human health.
33,34
The protective
effects of vegetables and fruit may in part be
attributed to antioxidant vitamins and specific poly-
phenols that display powerful inhibition of oxidative
stress. However, we have earlier reported that the
anti-platelet potential of the fruits appeared to be
unrelated to their antioxidant activity.
9,24,26
Although
further research on identification of the active
compounds requires for definitive conclusions.
Given the role of blood lipids in the development
of atherosclerosis and CVD and the positive roles of
fruits and vegetables on plasma lipids,
35–37
we have
also assessed the effects of kiwi fruit on plasma lipids.
Lowering of plasma triglycerides by kiwi fruit was
observed despite these volunteers maintaining their
regular diet during the supplementation periods.
None of the volunteers reported any loss of appetite
or changes in their food intake during the supple-
mentation. The mechanism of action is not known; it
is possible that the presence of certain components in
kiwi fruit may be responsible for the lipid-lowering
effects. However, further work is required to under-
stand the mechanism of action. It must be noted that
the lipid-lowering effects of fruits and vegetables were
also reported before.
35–37
In conclusion, consuming kiwi fruit is an effective
way of inhibiting platelet aggregation induced by
collagen and ADP in human volunteers. Our data
thus provide evidence that consuming kiwi fruit has
the potential to increase the effectiveness of throm-
bosis prophylaxis. Modulation of platelet reactivity
towards collagen, ADP and plasma triglyceride levels
by kiwi fruit could be of potentially prophylactic
and therapeutic benefit in preventing and halting
pathological processes that lead to CVD.
Acknowledgements
This work was supported by the International Kiwi Fruit
Organization (IKO). We are thankful to Mr Hamid Shergafi for
his technical assistance and Ms Anette Karlson for vitamin C
analysis. We are also grateful to BAMA, Norway, and Zespri,
New Zealand, for supplying us kiwi fruit for this study.
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292 KIWI FRUIT CONSUMPTION
... 18 The potential adverse effects of standard antiplatelet therapies 19 encourage us to use medicinal herbs, particularly for the primary prevention of cardiovascular disease. Various mechanisms have been proposed for inhibiting platelet aggregation through medicinal herbs, including the inhibition of the collagen and adenosine diphosphate (ADP) pathway, 20 an increase in the basal levels of tyrosine phosphorylation, 21 the inhibition of cyclooxygenase activity, 22 the inhibition of thromboxane A2 production, 17 and the reduction of intracellular Ca 2+ mobilization. 23 The current medical literature still lacks a systematic review on the antiplatelet activity of herbs. ...
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Background: Platelet aggregation is a crucial mechanism in the progression of atherothrombotic events. This systematic review aims to introduce the plants studied in healthy people as primary prevention to inhibit platelet aggregation. We also discuss possible mechanisms that are involved in the inhibition of platelet aggregation. Methods: A systematic search on the electronic medical databases from 1970 to February 2020 was performed. The selected keywords were: "herb", "plant", "platelet aggregation", "platelet activation", "clinical trial", "randomized" and "controlled". Results: The result of the initial search was a pool of 136 articles. After initial abstract reviewing, there were 55 relevant articles. Finally, 28 eligible records fulfilled our inclusion criteria to enter the qualitative synthesis process. Conclusion: Out of the 10 plants evaluated in the clinical trials, nine had inhibitory effects on platelet aggregation. Most of the reviewed plants, including tomato (Solanum lycopersicum L), garlic (Allium sativum), kiwifruit (Actinidia deliciosa), cacao (Theobroma cacao), grape (Vitis vinifera), ginkgo (Ginkgo biloba), flaxseed (Linum usitatissimum), sea buckthorn berry (Hippophae), and argan (Argania spinose) could be potential sources for the primary prevention of atherothrombotic events at an appropriate dosage. Finally, we do not consider phytoceuticals as a replacement for the guideline-directed medical treatment. Large randomized, double-blind clinical trials are required to evaluate the anti-platelet characteristics of these plants for the adjuvant primary prevention of cardiovascular disease.
... AD is reputed as an essential source of polyphenols, dietary fibers, protein, calcium, iron, and various vitamins, especially vitamin C [5,6]. AD has many biological activities, including antioxidant, anticancer, amendment of platelet accumulation, regulation of lipids level, lowering blood pressure, and modification of inflammation process [5,7,8]. erefore, the present work is designed to investigate the antihyperglycemic and antioxidant potentiality of Actinidia deliciosa aqueous extract against oxidative stress and pancreatic deterioration in diabetic rats. ...
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The present study evaluated the antioxidant capacity and antidiabetic effect of Actinidia deliciosa in diabetic rats. Rats were grouped as follows: control, Actinidia deliciosa aqueous extract (ADAE, 1 g/kg, daily and orally), streptozotocin (STZ, 50 mg/kg BW, single intraperitoneal dose), and STZ plus ADAE, respectively. Twenty-eight components were detected by GC-MS analysis with high phenolic contents and high DPPH scavenging activity. In vivo results revealed that rats treated with STZ showed a highly significant elevation in blood glucose and a decrease in insulin hormone levels. Thiobarbituric acid-reactive substances and hydrogen peroxide levels were elevated, while bodyweight, enzymatic, and nonenzymatic antioxidants were significantly decreased. Furthermore, histopathological and immunohistochemical insulin expression, besides ultrastructure microscopic variations (β-cells, α-cells, and δ-cells), were seen in pancreas sections supporting the obtained biochemical changes. Otherwise, rats supplemented with ADAE alone showed an improved antioxidant status and declined lipid peroxidation. Moreover, diabetic rats augmented with ADAE showed significant modulation in oxidative stress markers and different pancreatic tissue investigations compared to diabetic ones. Conclusively, ADAE has a potent antioxidant and hypoglycemic influence that may be utilized as a health-promoting complementary therapy in diabetes mellitus.
... It is commonly known as kiwifruit, and the species is originated in China [9]. A. deliciosa is considered one of the extremely important sources of polyphenols, dietary fibers, protein, calcium, iron, and various vitamins especially vitamin C [10]. It has many biological activities including antioxidant, anticancer, amendment of platelet aggregation, regulation of lipids, lowering of blood pressure, and inflammation progress [10,11]. Therefore, the present work objective is to investigate the possible antidiabetic, antihyperlipidemic, and antioxidant effects of A. deliciosa aqueous extract in STZ-induced diabetic rats. ...
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The present research intended to assess the possible protective and hypoglycemic effect of Actinidia deliciosa fruit aqueous extract (ADAE) in diabetic rats. The scavenging antioxidant capabilities of ADAE were evaluated using GC-MS analysis. In addition, rats were divided into four groups: control, ADAE, streptozotocin-induced DM (STZ), and STZ-treated rats + ADAE in an in vivo investigation. GC-MS analysis of ADAE was shown to include major components with high total phenolic contents and high DPPH scavenging activity. In diabetic rats, significant elevation in blood glucose level, lipid peroxidation, bilirubin, and lactate dehydrogenase activity as well as a change in lipid profile was observed, while insulin, body and liver weights, enzymatic and nonenzymatic antioxidants, liver function biomarkers, and protein content were significantly decreased. Furthermore, changes in the expression of the peroxisome proliferator-activated receptor (PPAR-γ), apoptotic, and inflammation-related genes were found. In addition, histological differences in rat liver tissue architecture were discovered, corroborating the biochemical modifications. However, consuming ADAE alone reduced lipid peroxidation and improved antioxidant status. Furthermore, diabetic rats given ADAE showed significant reductions in oxidative stress indicators and biochemical parameters, as well as improved tissue structure, when compared to the diabetic rats’ group. Also, ADAE supplementation protects diabetic rats’ hepatic tissue by upregulating PPAR-γ and downregulating apoptotic and inflammatory-related gene expression. In conclusion, A. deliciosa has beneficial protective effects so, it might be used as a complementary therapy in diabetes mellitus.
... •By preventing the rapid onset of the atherosclerotic process Fidrianny et al, 60 Prabhu et al; 61 64 Asgary and Keshvari, 65 73 Iwasawa et al, 72 Jung et al, 76 Karlsen et al, 79 Padmanabhan and Paliyath, 78 Al-Jarallah et al, 116 Cao et al, 85 Haghighian et al, 94 Jadeja et al, 90 Mohan et al, 83 Shao et al, 93 Sun et al, 89 100 Gayosso-García et al, 97 Hiraga et al, 98 Santana et al, 95 Wilson et al 96 ...
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Cardiovascular diseases (CVDs) are one of the leading causes of morbidity and mortality in both developed and developing countries, affecting millions of individuals each year. Despite the fact that successful therapeutic drugs for the management and treatment of CVDs are available on the market, nutritional fruits appear to offer the greatest benefits to the heart and have been proved to alleviate CVDs. Experimental studies have also demonstrated that nutritional fruits have potential protective effects against CVDs. The aim of the review was to provide a comprehensive summary of scientific evidence on the effect of 10 of the most commonly available nutritional fruits reported against CVDs and describe the associated mechanisms of action. Relevant literatures were searched and collected from several scientific databases including PubMed, ScienceDirect, Google Scholar and Scopus. In the context of CVDs, 10 commonly consumed nutritious fruits including apple, avocado, grapes, mango, orange, kiwi, pomegranate, papaya, pineapple, and watermelon were analysed and addressed. The cardioprotective mechanisms of the 10 nutritional fruits were also compiled and highlighted. Overall, the present review found that the nutritious fruits and their constituents have significant benefits for the management and treatment of CVDs such as myocardial infarction, hypertension, peripheral artery disease, coronary artery disease, cardiomyopathies, dyslipidemias, ischemic stroke, aortic aneurysm, atherosclerosis, cardiac hypertrophy and heart failure, diabetic cardiovascular complications, drug-induced cardiotoxicity and cardiomyopathy. Among the 10 nutritional fruits, pomegranate and grapes have been well explored, and the mechanisms of action are well documented against CVDs. All of the nutritional fruits mentioned are edible and readily accessible on the market. Consuming these fruits, which may contain varying amounts of active constituents depending on the food source and season, the development of nutritious fruits-based health supplements would be more realistic for consistent CVD protection.
... 95 Regular consumption of kiwi, also containing polyphenols, though led to a reduced collagen/ADP-induced platelet aggregation. 96 Anthocyanidins (IIa): dark grape juice or anthocyanin supplement. Surprisingly strong antiplatelet effects were reported after regular intake of anthocyanin-rich food additives, in 11 small-to medium-sized controlled studies. ...
Article
Cardiovascular disease, in particular due to arterial thrombosis, is a leading cause of mortality and morbidity, with crucial roles of platelets in thrombus formation. For multiple plant-derived phytochemicals found in common dietary components, claims have been made regarding cardiovascular health and antiplatelet activities. Here we present a systematic overview of the published effects of common phytochemicals, applied in vitro or in nutritional intervention studies, on agonist-induced platelet activation properties and platelet signaling pathways. Comparing the phytochemical effects per structural class, we included general phenols: curcuminoids (e.g., curcumin), lignans (honokiol, silybin), phenolic acids (caffeic and chlorogenic acid), derivatives of these (shikimic acid) and stilbenoids (isorhapontigenin, resveratrol). Furthermore, we evaluated the flavonoid polyphenols, including anthocyanidins (delphinidin, malvidin), flavan-3-ols (catechins), flavanones (hesperidin), flavones (apigenin, nobiletin), flavonols (kaempferol, myricetin, quercetin), isoflavones (daidzein, genistein); and terpenoids including carotenes and limonene; and finally miscellaneous compounds like betalains, indoles, organosulfides (diallyl trisulfide) and phytosterols. We furthermore discuss the implications for selected phytochemicals to interfere in thrombosis and hemostasis, indicating their possible clinical relevance. Lastly, we provide guidance on which compounds are of interest for further platelet-related research.
... Thus, it showed protective effects against vascular damage caused by oxidation of LDL. These findings are in accordance with those found by Duttaroy and Jørgensen [36]. The reduction in the concentration of LDL cholesterol may be accredited to bioactive compounds with higher antioxidant potential present in mango peels. ...
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Obesity is a chronic metabolic and noncommunicable disease that affects 50% of world population. Reactive oxygen species and oxidative stress are interconnected with the obesity and several metabolic disorders, gaining the attention of scientific community to combat this problem naturally. Among various fruits, mango as a yellow fruit is rich in polyphenols, carotenoids, terpenes, and flavonoids that act as antioxidants to protect against free radicals produced in the body. The present study was performed to explore in vivo antioxidant potential of mango peels against dyslipidemia and oxidative stress in overweight subjects. The female volunteers (n=31) between 25 and 45 years of age having a body mass index (BMI) of 25.0-29.9 (overweight) were included in this study, while participants with complications as diabetes, hypertension, cardiovascular, and liver diseases were excluded. The treatment group consumed 1 g mango peel powder for 84 days. The subjects were analyzed for biochemical analysis, antioxidant status, and anthropometric measurements at baseline and end of the study period. Further, at the end of study, the safety evaluation tests were also performed. The results showed that upon consumption of mango peel powder, low-density lipoproteins (LDL), cholesterol, triglyceride, urea, and creatinine levels were decreased and high-density lipoprotein (HDL) level was increased (P≤0.05), while thiobarbituric acid reactive substances (TBARS) showed increased antioxidant status (P≤0.05) which suggests that mango peels have a strong management potential against oxidative stress and dyslipidemia in obese subjects.
... In an intervention trial that lasts for 8 weeks, berry consumption resulted in favorable changes in platelet function, and antiplatelet activity was induced by both ADP and collagen [106]. Similar findings were also stated when consuming 2 or 3 kiwi fruits per day for 28 days [107]. The daily consumption of 50 mL of pomegranate juice (1.5 mmol total polyphenols) for 2 weeks was found to reduce LDL susceptibility to aggregation and retention and to increase the activity of serum paraoxonase by 20% [108]. ...
Article
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Cardiovascular diseases (CVD) are one of the main causes of mortality in the world. The development of these diseases has a specific factor-alteration in blood platelet activation. It has been shown that phenolic compounds have antiplatelet aggregation abilities and a positive impact in the management of CVD, exerting prominent antioxidant, anti-inflammatory, antitumor, cardioprotective, antihyperglycemic, and antimicrobial effects. Thus, this review is intended to address the antiplatelet activity of phenolic compounds with special emphasis in preventing CVD, along with the mechanisms of action through which they are able to prevent and treat CVD. In vitro and in vivo studies have shown beneficial effects of phenolic compound-rich plant extracts and isolated compounds against CVD, despite that the scientific literature available on the antiplatelet aggregation ability of phenolic compounds in vivo is scarce. Thus, despite the current advances, further studies are needed to confirm the cardioprotective potential of phenolic compounds towards their use alone or in combination with conventional drugs for effective therapeutic interventions.
... [9] The edible seeds contain 62% alpha-linolenic acid, an omega-3 fatty acid and antioxidants. [10] It has been used in traditional folk remedy for many diseases and show potent anti-hepatotoxic, anti-pyorrheal and prevent gingival inflammation. [11] In our present study, we have investigated the effect of the ethanolic extracts of Persea americana and Actinidia deliciosa on the oxidative stress parameters of Sodium selenite induced cataract in Wistar albino rats. ...
Article
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The effect of ethanolic extracts of Persea americana and Actinidia deliciosa on the oxidative stress parameters of sodium selenite induced cataract in Wistar albino rats was studied. The experimental rats were grouped into 6: Group I-Normal controls, Group II-sodium selenite cataract induced animals (developed cataract), Group III-Persea americana extract co-treated animals, Group IV-Actinidia deliciosa extract co-treated animals, Group V-Persea americana and Actinidia deliciosa extract co-treated animals (animals were co-treated for 28 days with each of the plant extract after sodium selenite induction) Group VI-standard Ascorbic acid co-treated animals(animals were co-treated for 28 days after sodium selenite induction). Body weight, organ weight and insulin level of selenite induced cataract animals decreased while plant treatment prevented this loss. Increase in values of glucose, glycated haemoglobin, creatinine, urea and uric acid levels were observed in selenite induced cataract rats, while plant treated groups restored these levels. The changes in lipid profile in Group II rats were prevented by treatment. Animals with sodium selenite induced cataract showed elevated levels of lipid peroxides and conjugated dienes, while Persea americana, Actinidia deliciosa and Ascorbic acid co-treated groups showed lower levels. Enzymatic antioxidants (superoxide dismutase, catalase, glutathione peroxidase, glutathione S transferase) activities decreased in rats with sodium selenite cataract while both the plant and standard ascorbic acid co-treated animals showed increased enzymatic antioxidant levels. Similarly, levels of non-enzymatic antioxidants such as vitamin C and total protein decreased in sodium selenite cataract rats, Vol 5, Issue 8, 2016. 682 Indumathi et al. World Journal of Pharmaceutical Research while both the plant and standard ascorbic acid treated animals showed increased levels. The above results thus, signify the antioxidative and anticataract potential of both Persea americana and Actinidia deliciosa.
Article
Kiwi fruit (KF) (Actinidia deliciosa L.) are members of the Actinidia genus (Family Actinidiaceae). Previously these plants have confirm anti-diabetic, anti-oxidant, anti-inflammatory, antifungal, anticarcinogenic, hepatoprotective, anti-microbial etc. properties. The therapeutic efficacy of complex phytoconstituents found in fruit extracts has piqued the interest of pharmaceutical companies and academics alike. Methanolic extract of kiwi fruit (MEKF) was analyzed by gas chromatography-mass spectroscopy and yielded positive results signaling towards identification and characterization of therapeutic claims of this species in the traditional system. The antioxidant activity of MEKF was determined by the most suitable DPPH method. The most significant constituents found in MEKF are 2-cyclohexylpiperidine (0.58%), phenol, 2,4-bis(1,1-dimethylethyl)- (0.13%), 1,6-anhydro- β-d-glucopyranose (0.52%), dodecanoic acid (0.32%), 2-heptenoic acid, trimethylsilyl ester (2.84%), Tetradecanoic acid (1.87%), Neophytadiene (2.81%), Hexahydro farnesyl acetone (1.72%), Neophytadiene (0.97%), n-hexadecanoic acid (19.00%), Ethyl hexadecanoate (7.21%), Linoleic acid ethyl ester (0.23%), Phytol (4.74%), α-linolenic acid (16.73%), Ethyl (9z,12z)-9,12-octadecadienoate (2.92%), Octadecanoic acid (4.76%), Octadecanoic acid, 17-methyl-, methyl ester (1.68%), Phytol, acetate (0.15%), 2-Methylhexacosane (0.97%), Ethyl 9,12,15-octadecatrienoate (0.81%), Tetracontane (1.45%), α-tocospiro A (0.15%), α-tocospiro B (0.19%), 3.β-Acetoxystigmasta-4,6,22-triene (0.24%), Octacosane, 1-iodo (0.43%), 4,6-cholestadien-3.β-ol, benzoate (2.14%), γ.-Sitosterol (4.40%), and Tigogenin (2.32%). The found results in the analysis of the antioxidant activity of MEKF showed significant free radical scavenging capacity against DPPH-generated free radicals due to the presence of alkaloids, glycoside, terpenoids, vitamins, and some other reported compounds. In the pharmaceutical industry, GC-MS reports will be useful for identifying a wide range of phytoconstituents in polyherbal extracts and standardizing of plant materials.
Chapter
In addition to their roles in thrombotic events, hyperactive platelets play essential roles in atherosclerosis development. Currently available antiplatelet drugs are not suitable for use where the risk of a cardiovascular event is relatively low. Potent antiplatelet factors were identified in the water-soluble extract of tomato (Fruitflow), which lower blood pressure. Human volunteer studies demonstrated the potency and bioavailability of active compounds in Fruitflow. Fruitflow became the first product in Europe to obtain an approved, proprietary health claim under Article 13(5) of the European Health Claims Regulation 1924/2006 on nutrition and health claims made on foods. In addition to its reduction of platelet reactivity, Fruitflow contains antiangiotensin-converting enzyme and antiinflammatory factors, making it an effective bioactive against cardiovascular disease.
Article
DNA oxidation is a potential cause of cancer in humans. It is well-known that fruits and vegetables protect against cancer, and this may be in part because they contain antioxidants, which decrease the level of oxidation of DNA. However, there are other possible mechanisms, such as an enhancement of cellular repair of this damage. A randomized cross-over study was carried out on healthy human subjects, who were given kiwifruit as a supplement to their normal diet, for 3-week periods at different ‘doses’, with 2-week washout periods between doses. Endogenous oxidation of bases in lymphocyte DNA, and the resistance of the DNA to oxidation ex vivo, were assessed using single cell gel electrophoresis (the ‘comet assay’). The capacity to repair DNA base oxidation was measured with an in vitro test, and levels of expression of repair-related genes OGG1 and APE1 were assessed by semi-quantitative RT–PCR. Concentrations of dietary antioxidants were measured in plasma. The antioxidant status of plasma and of lymphocytes was increased by consumption of kiwifruit. Levels of endogenous oxidation of pyrimidines and purines in DNA were markedly decreased, and DNA repair measured on a substrate containing 8-oxo-7,8-dihydroguanine was substantially increased (without change in levels of OGG1 or APE1 mRNA). The magnitude of these effects was generally not related to the number of kiwifruits consumed per day. Kiwifruit provides a dual protection against oxidative DNA damage, enhancing antioxidant levels and stimulating DNA repair. It is probable that together these effects would decrease the risk of mutagenic changes leading to cancer.
Article
Objective. —To examine prospectively the relationship between dietary fiber and risk of coronary heart disease.Design. —Cohort study.Setting. —In 1986, a total of 43 757 US male health professionals 40 to 75 years of age and free from diagnosed cardiovascular disease and diabetes completed a detailed 131 -item dietary questionnaire used to measure usual intake of total dietary fiber and specific food sources of fiber.Main Outcome Measure. —Fatal and nonfatal myocardial infarction (Ml).Results. —During 6 years of follow-up, we documented 734 cases of Ml (229 were fatal coronary heart disease). The age-adjusted relative risk (RR) for total Ml was 0.59 (95% confidence interval [CI], 0.46 to 0.76) among men in the highest quintile of total dietary fiber intake (median, 28.9 g/d) compared with men in the lowest quartile (median, 12.4 g/d). The inverse association was strongest for fatal coronary disease (RR, 0.45; 95% CI, 0.28 to 0.72). After controlling for smoking, physical activity and other known nondietary cardiovascular risk factors, dietary saturated fat, vitamin E, total energy intake, and alcohol intake, the RRs were only modestly attenuated. A 10-g increase in total dietary fiber corresponded to an RR for total Ml of 0.81 (95% CI, 0.70 to 0.93). Within the three main food contributors to total fiber intake (vegetable, fruit, and cereal), cereal fiber was most strongly associated with a reduced risk of total Ml (RR, 071; 95% CI, 0.55 to 0.91 for each 10-g increase in cereal fiber per day).Conclusions. —Our results suggest an inverse association between fiber intake and Ml. These results support current national dietary guidelines to increase dietary fiber intake and suggest that fiber, independent of fat intake, is an important dietary component for the prevention of coronary disease.(JAMA. 1996;275:447-451)
Article
THIS is the second of a two-part article on the results of randomized trials of treatments designed to reduce mortality or major morbidity in heart disease. Our goal is to summarize the results of trials of common treatments on major outcomes in unstable angina, congestive heart failure, primary prevention with aspirin, and risk factor modification. This summary should provide useful background information against which clinicians must consider other information (eg, patient prognosis, risk of side effects, drug interactions, and specific clinical picture) in making decisions about individual patients. We do not deal in either article with trials of coronary artery bypass graft surgery for stable angina, trials of valve replacement, or congenital heart disease. The risk reductions are based on the odds ratio calculated by the Mantel-Haenszel method as applied to combining data from several trials. When event rates are low, the odds ratio and the relative risk are numerically
Article
Quercetin and 12 other natural flavonoid aglycones inhibit washed human platelet aggregation and secretion of serotonin induced by ADP, collagen or thrombin. The inhibitory effect of flavonoids is of the same order of magnitude as IBMX and dipyridamole. The structural features required for a flavonoid to inhibit human platelet function are similar to those previously reported by us to inhibit cyclic nucleotide phosphodiesterase. The inhibitory effect of flavonoids on human platelet function was diminished by saturation of the C-2, C-3 double bond, lack of the C-4 carbonyl, glycosylation at C-3 and a high number of hydroxyl substituents.
Article
Coronary artery disease is responsible for much mortality and morbidity around the world. Platelets are involved in atherosclerotic disease development and the reduction of platelet activity by medications reduces the incidence and severity of disease. Red wine and grapes contain polyphenolic compounds, including flavonoids, which can reduce platelet aggregation and have been associated with lower rates of cardiovascular disease. Citrus fruits contain different classes of polyphenolics that may not share the same properties. This study evaluated whether commercial grape, orange and grapefruit juices, taken daily, reduce ex vivo platelet activity. In a randomized cross-over design, ten healthy human subjects (ages 26-58 y, five of each gender) drank 5-7.5 mL/(kg. d) of purple grape juice, orange juice or grapefruit juice for 7-10 d each. Platelet aggregation (whole blood impedance aggregometry, Chronolog Model #590) at baseline was compared to results after consumption of each juice. Drinking purple grape juice for one week reduced the whole blood platelet aggregation response to 1 mg/L of collagen by 77% (from 17.9 +/- 2.3 to 4.0 +/- 6.8 ohms, P = 0.0002). Orange juice and grapefruit juice had no effect on platelet aggregation. The purple grape juice had approximately three times the total polyphenolic concentration of the citrus juices and was a potent platelet inhibitor in healthy subjects while the citrus juices showed no effect. The platelet inhibitory effect of the flavonoids in grape juice may decrease the risk of coronary thrombosis and myocardial infarction.