Bioavailability and
pharmacokinetics of caffeoylquinic acids and flavonoids
after oral administration of Artichoke leaf extracts in humans.
Phytomedicine. 2005
Jan;12(1-2):28-38.
Extracts from artichoke leaves are traditionally used in the treatment of
dyspeptic and hepatic disorders. Various potential pharmacodynamic effects
have been observed in vitro for mono- and dicaffeoylquinic acids (e.g.
chlorogenic acid, cynarin), caffeic acid and flavonoids (e.g.
luteolin-7-O-glucoside) which are the main phenolic constituents of
artichoke leaf extract. However, in vivo not only the genuine extract
constituents but also their metabolites may contribute to efficacy.
Therefore, the evaluation of systemic availability of potential bioactive
plant constituents is a major prerequisite for the interpretation of in
vitro pharmacological testing. In order to get more detailed information
about absorption, metabolism and disposition of artichoke leaf extract,
two different extracts were administered to 14 healthy volunteers in a
crossover study. Each subject received doses of both extracts. Artichoke
leaf extract A administered dose: caffeoylquinic acids equivalent to 107.0
mg caffeic acid and luteolin glycosides equivalent to 14.4 mg luteolin.
Artichoke leaf extract B administered dose: caffeoylquinic acids
equivalent to 153.8 mg caffeic acid and luteolin glycosides equivalent to
35.2 mg luteolin. Urine and plasma analysis were performed by a validated
HPLC method using 12-channel coulometric array detection. In human plasma
or urine none of the genuine target extract constituents could be
detected. However, caffeic acid (CA), its methylated derivates ferulic
acid (FA) and isoferulic acid (IFA) and the hydrogenation products
dihydrocaffeic acid (DHCA) and dihydroferulic acid (DHFA) were identified
as metabolites derived from caffeoylquinic acids. Except of DHFA all of
these compounds were present as sulfates or glucuronides. Peak plasma
concentrations of total CA, FA and IFA were reached within 1 h and
declined over 24 h showing almost biphasic profiles. In contrast maximum
concentrations for total DHCA and DHFA were observed only after 6-7 h,
indicating two different metabolic pathways for caffeoylquinic acids.
Luteolin administered as glucoside was recovered from plasma and urine
only as sulfate or glucuronide but neither in form of genuine glucosides
nor as free luteolin. Peak plasma concentrations were reached rapidly
within 0.5 h. The elimination showed a biphasic profile.
Antifungal activity of Cynara
scolymus L. extracts.
Fitoterapia. 2005 Jan;76(1):108-11.
Chloroform, ethanol and ethyl acetate extracts of artichoke leaves, heads
and stems were tested for their antifungal activity using the agar-well
diffusion assay technique. The artichoke leaves extracts and the ethanol
fractions were found to be the most effective extract against all the
tested organisms.
Anaphylactic Reaction to Inulin:
First Identification of Specific IgEs to an Inulin Protein Compound.
Int Arch Allergy Immunol. 2005 Jan 12;136(2):155-158
Background: A woman with a past history of allergy to artichoke presented
with two episodes of immediate allergic reactions, one of which was a
severe anaphylactic shock after eating two types of health foods
containing inulin. Results: Dot blot assay techniques identified specific
IgEs to artichoke, to yoghurt F, and to a heated BSA + inulin product. Dot
blot inhibition techniques confirmed the anti-inulin specificity of
specific IgE. Conclusions: The absence of a positive reaction to an
unheated milk-inulin mixture indicates the probability of protein-inulin
binding. There is no cross-reactivity with the carbohydrates of the
glycosylated allergens.
Artichoke juice improves endothelial
function in hyperlipemia.
Life Sci. 2004 Dec 31;76(7):775-82.
Artichoke extracts have been shown to produce various pharmacological
effects, such as the inhibition of cholesterol biosynthesis and of LDL
oxidation. Endothelial dysfunction represents the first stage of
atherosclerotic disease. Aim of the study was to investigate the effects
of dietary supplementation with artichoke juice on brachial FMV of
hyperlipemics. We studied 18 moderately hyperlipemic patients (LDL
cholesterol > 130 <200 mg/dl and/or triglycerides >150 <250
mg/dl) of both genders and 10 hyperlipemic patients, matched for age, sex
and lipid parameters. In conclusion, artichoke dietary supplementation
seems to positively modulate endothelial function in hypercholesterolemia.
Phenolic compounds from the leaf
extract of artichoke (Cynara scolymus L.) and their antimicrobial
activities.
J Agric Food Chem. 2004 Dec 1;52(24):7272-8.
A preliminary antimicrobial disk assay of chloroform, ethyl acetate, and
n-butanol extracts of artichoke (Cynara scolymus L.) leaf extracts showed
that the n-butanol fraction exhibited the most significant antimicrobial
activities against seven bacteria species, four yeasts, and four molds.
Eight phenolic compounds were isolated from the n-butanol soluble fraction
of artichoke leaf extracts. The isolated compounds were examined for their
antimicrobial activities on the above microorganisms, indicating that all
eight phenolic compounds showed activity against most of the tested
organisms. Among them, chlorogenic acid, cynarin, luteolin-7-rutinoside,
and cynaroside exhibited a relatively higher activity than other
compounds; in addition, they were more effective against fungi than
bacteria.
Artichoke leaf extract reduces
symptoms of irritable bowel syndrome and improves quality of life in
otherwise healthy volunteers suffering from concomitant dyspepsia: a
subset analysis.
J Altern Complement Med. 2004 Aug;10(4):667-9.
OBJECTIVES: Does artichoke leaf extract ameliorate symptoms of Irritable
bowel syndrome (IBS) in otherwise healthy volunteers suffering concomitant
dyspepsia? METHODS: A subset analysis of a previous dose-ranging, open,
postal study, in adults suffering dyspepsia. Two hundred and eight (208)
adults were identified post hoc as suffering with IBS. IBS incidence,
self-reported usual bowel pattern, and the Nepean Dyspepsia Index (NDI)
were compared before and after a 2-month intervention period. RESULTS:
There was a significant fall in IBS incidence of 26.4% after treatment. A
significant shift in self-reported usual bowel pattern away from
"alternating constipation/diarrhea" toward "normal"
was observed. NDI total symptom score significantly decreased by 41% after
treatment. Similarly, there was a significant 20% improvement in the NDI
total quality-of-life (QOL) score in the subset after treatment.
CONCLUSION: This report supports previous findings that Artichoke leaf
extract ameliorates symptoms of IBS,
plus improves health-related QOL.
Flavonoids from artichoke (Cynara
scolymus L.) up-regulate endothelial-type nitric-oxide synthase gene
expression in human endothelial cells.
J Pharmacol Exp Ther. 2004 Sep;310(3):926-32.
Nitric oxide (NO) produced by endothelial nitric-oxide synthase (eNOS)
represents an antithrombotic and anti-atherosclerotic principle in the
vasculature. Hence, an enhanced expression of eNOS in response to
pharmacological interventions could provide protection against
cardiovascular diseases. In EA.hy 926 cells, a cell line derived from
human umbilical vein endothelial cells (HUVECs), an artichoke leaf extract
increased the activity of the human eNOS promoter (determined by
luciferase reporter gene assay). An organic subfraction from artichoke
leaf extract was more potent in this respect than the crude extract,
whereas an aqueous subfraction of artichoke leaf extract was without
effect. Thus, in addition to the lipid-lowering and antioxidant properties
of artichoke, an increase in eNOS gene transcription may also contribute
to its beneficial cardiovascular profile. Artichoke flavonoids are likely
to represent the active ingredients mediating eNOS up-regulation.
Effectiveness of artichoke extract
in preventing alcohol-induced hangovers: a randomized controlled trial.
CMAJ. 2003 Dec 9;169(12):1269-73.
Extract of globe artichoke (Cynara scolymus) is promoted as a possible
preventive or cure for alcohol-induced hangover symptoms. However, few
rigorous clinical trials have assessed the effects of artichoke extract,
and none has examined the effects in relation to hangovers. We undertook
this study to test whether artichoke extract is effective in preventing
the signs and symptoms of alcohol-induced hangover. Our results suggest
that artichoke extract is not effective in preventing the signs and
symptoms of alcohol-induced hangover.
Efficacy of artichoke leaf extract
in the treatment of patients with functional dyspepsia: a six-week
placebo-controlled, double-blind, multicentre trial.
Aliment Pharmacol Ther. 2003 Dec;18(11-12):1099-105.
This study aimed to assess the efficacy of artichoke leaf extract in the
treatment of patients with functional dyspepsia (FD). METHODS: In a
double-blind, randomized controlled trial (RCT), 247 patients with
functional dyspepsia were recruited and treated with either a commercial
artichoke leaf extract preparation (2 x 320 mg plant extract t.d.s.) or a
placebo. The primary efficacy variable was the sum score of the patient's
weekly rating of the overall change in dyspeptic symptoms (four-point
scale). Secondary variables were the scores of each dyspeptic symptom and
the quality of life (QOL) as assessed by the Nepean Dyspepsia Index (NDI).
RESULTS: Two hundred and forty-seven patients were enrolled, and data from
244 patients (129 active treatment, 115 placebo) were suitable for
inclusion in the statistical analysis (intention-to-treat). The overall
symptom improvement over the 6 weeks of treatment was significantly
greater with artichoke leaf extract than with the placebo. Similarly,
patients treated with artichoke leaf extract showed significantly greater
improvement in the global quality-of-life scores (NDI) compared with the
placebo-treated patients. CONCLUSION: The artichoke leaf extract
preparation tested was significantly better than the placebo in
alleviating symptoms and improving the disease-specific quality of life in
patients with functional dyspepsia.
Screening pharmaceutical
preparations containing extracts of turmeric rhizome, artichoke leaf,
devil's claw root and garlic or salmon oil for antioxidant capacity.
J Pharm Pharmacol. 2003 Jul;55(7):981-6.
Pharmaceutical preparations derived from natural sources such as
vegetables often contain compounds that contribute to the antioxidant
defence system and apparently play a role in the protection against
degenerative diseases. In the present study, commercial preparations
containing extracts of turmeric, artichoke, devil's claw and garlic or
salmon oil were investigated. All fractions of the turmeric extract
preparation exhibited pronounced antioxidant activity, which was assigned
to the presence of curcumin and other polyphenols. The antioxidant
activity corresponding to the artichoke leaf extract was higher in the
aqueous fractions than in the lipophilic fractions. Similarly, devil's
claw extract was particularly rich in water-soluble antioxidants.
Harpagoside, a major compound in devil's claw, did not contribute
significantly to its antioxidant activity. The antioxidant capacity of the
garlic preparation was poor in the TEAC assay. That of salmon oil was
mainly attributed to vitamin E, which is added to the product for
stabilization. In all test preparations, the antioxidant activity was
significantly correlated with the content of total phenolic compounds.
Artichoke leaf extract reduces mild
dyspepsia in an open study.
Phytomedicine. 2002 Dec;9(8):694-9.
A recent post-marketing study indicated that high doses of standardised
artichoke leaf extract may reduce symptoms of dyspepsia. To substantial
these findings, this study investigated the efficacy of a low-dose
artichoke leaf extract on amelioration of dyspeptic symptoms and
improvement of quality of life. The study was an open, dose-ranging postal
study. Healthy patients with self-reported dyspepsia were recruited
through the media. The Nepean Dyspepsia Index and the State-Trait Anxiety
Inventory were completed at baseline and after 2 months of treatment with
artichoke leaf extract, which was randomly allocated to volunteers as 320
or 640 mg daily. Of the 516 participants, 454 completed the study. In both
dosage groups, compared with baseline, there was a significant reduction
of all dyspeptic symptoms, with an average reduction of 40% in global
dyspepsia score. However, there were no differences in the primary outcome
measures between the two groups, although relief of state anxiety, a
secondary outcome, was greater with the higher dosage. Health-related
quality of life was significantly improved in both groups compared with
baseline. We conclude that artichoke leaf extract shows promise to
ameliorate upper gastro-intestinal symptoms and improve quality of life in
otherwise healthy subjects suffering from dyspepsia.
Choleretic activity and biliary
elimination of lipids and bile acids induced by an artichoke leaf extract
in rats.
Phytomedicine. 2002 Dec;9(8):687-93.
The therapeutic properties of artichoke (Cynara scolymus L.) preparations
have been known since ancient times. The traditional use of artichoke leaf
extract in gastroenterology is mainly based upon its strong antidyspeptic
actions which are mediated by its choleretic activity. The aim of this
study was to investigate the effects of artichoke leaf extract on bile
flow and the formation of bile compounds in anaesthetised Wistar rats
after acute and repeated (twice a day for 7 consecutive days) oral
administration. A significant increase in bile flow was observed after
acute treatment with artichoke leaf extract as well as after repeated
administration. The choleretic effects of artichoke leaf extract were
similar to those of the reference compound dehydrocholic acid (DHCA).
Total bile acids, cholesterol and phospholipid were determined by
enzymatic assays. There was a strong artichoke leaf extract -induced
increase in total bile acid concentration over the entire experiment. With
the highest dose (400 mg/kg), a significant increase was obtained after
single and repeated administration. The bile acids-increased effects of
artichoke leaf extract were much more pronounced than those of reference (DHCA).
No significant differences in cholesterol and phospholipid content could
be found.
Artichoke leaf extract for treating
hypercholesterolaemia.
Cochrane Database Syst Rev. 2002;(3):CD003335.
BACKGROUND: Hypercholesterolaemia is directly associated with an increased
risk for coronary heart disease and other sequelae of atherosclerosis.
Artichoke leaf extract (Artichoke leaf extract), which is available as an
over-the-counter remedy, has been implicated in lowering cholesterol
levels. Whether Artichoke leaf extract is truly efficacious for this
indication, however, is still a matter of debate. OBJECTIVES: To assess
the evidence of Artichoke leaf extract versus placebo or reference
medication for treating hypercholesterolaemia defined as mean total
cholesterol levels of at least 5.17 mmol/L (200 mg /dL). REVIEWER'S
CONCLUSIONS: Few data from rigorous clinical trials assessing Artichoke
leaf extract for treating hypercholesterolaemia exist. Beneficial effects
are reported, the evidence however is not compelling. The limited data on
safety suggest only mild, transient and infrequent adverse events with the
short term use of Artichoke leaf extract. More rigorous clinical trials
assessing larger patient samples over longer intervention periods are
needed to establish whether Artichoke leaf extract is an effective and
safe treatment option for patients with hypercholesterolaemia.
Artichoke leaf extract reduces
symptoms of irritable bowel syndrome in a post-marketing surveillance
study.
Phytother Res. 2001 Feb;15(1):58-61.
Irritable bowel syndrome (IBS) is a problem reported to affect 22% of the
general population. It is characterized by abdominal pain and altered
bowel habit, but has so far defied elucidation of its pathogenesis and
proved difficult to treat. There is a growing body of evidence which
indicates therapeutic properties for artichoke leaf extract. Dyspepsia is
the condition for which the herb is specifically indicated, but the
symptom overlap between dyspeptic syndrome and IBS has given rise to the
notion that artichoke leaf extract may have potential for treating IBS as
well. A sub-group of patients with IBS symptoms was therefore identified
from a sample of individuals with dyspeptic syndrome who were being
monitored in a post-marketing surveillance study of artichoke leaf extract
for 6 weeks. Analysis of the data from the IBS sub-group revealed
significant reductions in the severity of symptoms and favourable
evaluations of overall effectiveness by both physicians and patients.
Furthermore, 96% of patients rated artichoke leaf extract as better than
or at least equal to previous therapies administered for their symptoms,
and the tolerability of artichoke leaf extract was very good. These
results provide support for the notion that artichoke leaf extract has
potential value in relieving IBS symptoms and suggest that a controlled
trial is justified.
Efficacy of Artichoke dry extract in
patients with hyperlipoproteinemia.
Arzneimittelforschung. 2000 Mar;50(3):260-5.
Efficacy and tolerability of artichoke dry extract (drug/extract ratio
25-35:1, aquous extract, CY450) as coated tablets containing 450 mg
extract (tradename: Valverde Artischocke bei Verdauungsbeschwerden) was
investigated in the treatment of hyperlipoproteinemia and compared with
placebo. 143 adult patients with initial total cholesterol of > 7.3
mmol/l (> 280 mg/dl) were included in a double blind, randomized,
placebo controlled, multi-center clinical trial. Patients received 1,800
mg artichoke dry extract per day or placebo over 6 weeks. Changes of total
cholesterol and LDL-cholesterol from baseline to the end of treatment
showed a statistically significant superiority of artichoke dry extract
over placebo. There were no drug related adverse events during this study
indicating an excellent tolerability of artichoke dry extract. This
prospective study could contribute clear evidence to recommend artichoke
dry extract CY450 for treating hyperlipoproteinemia and, thus, prevention
of atherosclerosis and coronary heart disease.
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