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Research Abstracts
Plant
metabolites as nootropics and cognitives
Ceska
Slov Farm. 2006 Sep;55(5):219-29.
*
Cervenka F, * Jahodar L.
Univerzita
Karlova v Praze, Farmaceuticka fakulta v Hradci Kralove, Katedra
farmaceuticke botaniky a ekologie. frantisek.cervenka@faf.cuni.cz
Nowadays
several millions of people suffer from Alzheimer's disease and other
types of dementia. Etiology of these diseases is not known very well.
There occur different levels of neurotransmitters, the level of
acetylcholine in the brain is decreased and pathological changes
affect the brain tissue. Organic and toxic damage of the brain, free
radicals, and other changes participate in the development of these
diseases. Drugs as nootropics, cognitives, and neuroprotectives are
commonly used to treat these diseases. Some of these drugs have often
side and undesirable effects. In recent years some natural substances
(galanthamine, huperzine A, vinpocetine), and standardized plant
extracts (Ginkgo biloba L., Centella asiatica L.) Urban, Bacopa
monniera L., Evolvulus alsinoides L.) are often used. These plant
preparations produce fewer undesirable effects and the same
effectiveness as the classic therapy, or these preparations are used
as a supplement to the classic therapy.
PMID:
17128592 [PubMed - indexed for MEDLINE]
Effects
of a combined extract of Ginkgo biloba and Bacopa monniera on
cognitive function in healthy humans.
Hum
Psychopharmacol. 2004 Mar;19(2):91-6.
*
Nathan PJ, * Tanner S, * Lloyd J, * Harrison B, * Curran L, * Oliver
C, * Stough C.
Neuropsychopharmacology
Laboratory, Brain Sciences Institute, Swinburne University, Victoria,
Australia. pnathan@bsi.swin.edu.au
Extracts
of Ginkgo biloba and Bacopa monniera have been shown to produce
positive effects on cognitive function in healthy subjects. While the
exact mechanisms are not known, it has been suggested that
antioxidant properties and cholinergic modulation may play a role. In
the current study the sub-chronic (2 weeks) and chronic (4 weeks)
effects of an extract containing Ginkgo biloba (120 mg) and Bacopa
monniera (300 mg) (Blackmores Ginkgo Brahmi) on cognitive function
were examined. The study was a randomized, double-blind,
placebo-controlled, independent group design in which 85 healthy
subjects were allocated to one of two treatment conditions (placebo
or combined Ginkgo biloba and Bacopa monniera extract). Testing was
conducted at baseline and 2 and 4 weeks post treatment. The results
showed that the combined extract relative to placebo did not
demonstrate any significant effects on tests investigating a range of
cognitive processes including attention, short-term and working
memory, verbal learning, memory consolidation, executive processes,
planning and problem solving, information processing speed, motor
responsiveness and decision making. These findings suggest that at
least within the current treatment duration and doses, an extract
containing Ginkgo biloba and Bacopa monniera had no cognitive
enhancing effects in healthy subjects. Copyright 2004 John Wiley &
Sons, Ltd.
PMID:
14994318 [PubMed - indexed for MEDLINE]
The
acute effects of an extract of Bacopa monniera (Brahmi) on cognitive
function in healthy normal subjects.
Hum
Psychopharmacol. 2001 Jun;16(4):345-351.
*
Nathan PJ, * Clarke J, * Lloyd J, * Hutchison CW, * Downey L, *
Stough C.
Neuropharmacology
Laboratory, Brain Sciences Institute, Swinburne University of
Technology, Australia.
The
Ayurvedic medicine Bacopa monniera (Brahmi) has been shown to exert
cognitive enhancing effects in animals. The current study examined
the acute effects of an extract of Bacopa monniera on cognitive
function in normal healthy human subjects. The study was a
double-blind, placebo-controlled independent group design in which
subjects were randomly allocated to one of two treatment conditions,
Bacopa monniera (300 mg) (n = 18) or placebo (n = 20).
Neuropsychological testing was conducted before and 2 h after drug
administration. No significant changes were found on any of the
tests. The findings suggest that Bacopa monniera, at least for the
dose administered, has no acute effects on cognitive functioning in
normal healthy subjects. Copyright 2001 John Wiley & Sons, Ltd. PMID:
12404571 [PubMed - as supplied by publisher]
A
comparative study in rodents of standardized extracts of Bacopa
monniera and Ginkgo biloba: anticholinesterase and cognitive
enhancing activities.
Pharmacol
Biochem Behav. 2002 Nov;73(4):893-900.
Das
A, * Shanker G, * Nath C, * Pal R, * Singh S, * Singh H.
Division
of Pharmacology, Central Drug Research Institute, P.O. Box 173,
Lucknow, 226 001, India. amitavadascdri@rediffmail.com
Bacopa
monniera and Ginkgo biloba are well-known cognitive enhancers in
Indian and Chinese traditional medicine systems. Standardized
extracts of B. monniera and G. biloba were used to evaluate the
antidementic and anticholinesterase activities in adult male Swiss
mice. Antidementic activity was tested against scopolamine (3 mg/kg
ip)-induced deficits in passive avoidance test. Three different
extracts of B. monniera (30 mg/kg) and extract of G. biloba (15, 30
and 60 mg/kg) were administered postoperatively, daily for 7 days and
60 min after the last dose, i.e., on Day 7, first trial was
conducted. In passive avoidance test, increased transfer latency time
(TLT) and no transfer response (NTR) were taken as criteria for
learning. TLT and NTR were significantly increased and decreased in
second trial, 24 h after the first trial in control group and
scopolamine-dementia group, respectively. The B. monniera- and G.
biloba-treated groups produced significant increase in TLT and NTR on
second trial (40-80%) after scopolamine treatment, thus, attenuating
its antidementic effect. Both the extracts showed a dose (10-1000
microg)-dependent inhibitory effect on acetylcholinesterase (AChE)
activity (in vitro), performed spectrophotometrically. IC(50) of G.
biloba was 268.33 microg, whereas none of the extracts of B. monniera
showed more than 50% inhibition. At a dose concentration of 30 and 60
mg/kg, extracts of G. biloba showed a cognitive enhancing property
and, at the same time, a significant decrease in AChE-specific
activity in both per se and scopolamine-dementia groups. These
extracts possess a significant anticholinesterase and antidementic
properties, which may be useful in the treatment of dementia.
PMID:
12213536 [PubMed - indexed for MEDLINE] Chronic
effects of Brahmi (Bacopa monnieri) on human memory.
Neuropsychopharmacology.
2002 Aug;27(2):279-81.
*
Roodenrys S, * Booth D, * Bulzomi S, * Phipps A, * Micallef C, *
Smoker J.
Department
of Psychology, University of Wollongong, Woolongong, Australia.
steven_roodenrys@uow.edu.au
A
study is reported on the effects of Brahmi (Bacopa monniera) on human
memory. Seventy-six adults aged between 40 and 65 years took part in
a double-blind randomized, placebo control study in which various
memory functions were tested and levels of anxiety measured. There
were three testing sessions: one prior to the trial, one after three
months on the trial, and one six weeks after the completion of the
trial. The results show a significant effect of the Brahmi on a test
for the retention of new information. Follow-up tests showed that the
rate of learning was unaffected, suggesting that Brahmi decreases the
rate of forgetting of newly acquired information. Tasks assessing
attention, verbal and visual short-term memory and the retrieval of
pre-experimental knowledge were unaffected. Questionnaire measures of
everyday memory function and anxiety levels were also unaffected.
PMID:
12093601 [PubMed - indexed for MEDLINE]
The
chronic effects of an extract of Bacopa monniera (Brahmi) on
cognitive function in healthy human subjects.
Psychopharmacology
(Berl). 2001 Aug;156(4):481-4.
Stough
C, * Lloyd J, * Clarke J, * Downey LA, * Hutchison CW, * Rodgers T, *
Nathan PJ.
Neuropsychology
Laboratory, School of Biophysical Science and Electrical Engineering,
Victoria, Australia.
RATIONALE:
Extracts of Bacopa monniera have been reported to exert cognitive
enhancing effects in animals. However, the effects on human cognition
are inconclusive. OBJECTIVE: The current study examined the chronic
effects of an extract of B. monniera (Keenmind) on cognitive function
in healthy human subjects. METHODS: The study was a double-blind
placebo-controlled independent-group design in which subjects were
randomly allocated to one of two treatment conditions, B. monniera
(300 mg) or placebo. Neuropsychological testing was conducted
pre-(baseline) and at 5 and 12 weeks post drug administration.
RESULTS: B. monniera significantly improved speed of visual
information processing measured by the IT task, learning rate and
memory consolidation measured by the AVLT (P<0.05), and state
anxiety (P<0.001) compared to placebo, with maximal effects
evident after 12 weeks. CONCLUSIONS: These findings suggest that B.
monniera may improve higher order cognitive processes that are
critically dependent on the input of information from our environment
such as learning and memory.
PMID:
11498727 [PubMed - indexed for MEDLINE]
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