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1.
Br J Nutr ; 127(2): 233-247, 2022 01 28.
Article in English | MEDLINE | ID: mdl-33143761

ABSTRACT

Vitamin C (ascorbic acid) is a water-soluble vitamin with an array of biological functions. A number of proposed factors contribute to the vitamin's plasma bioavailability and ability to exert optimal functionality. The aim of this review was to systematically assess plasma vitamin C levels post-surgery compared with pre-surgery/the magnitude and time frame of potential changes in concentration. We searched the PUBMED, SCOPUS, SciSearch and the Cochrane Library databases between 1970 and April 2020 for relevant research papers. Prospective studies, control groups and true placebo groups derived from controlled trials that reported means and standard deviations of plasma vitamin C concentrations pre- and postoperatively were included into the meta-analysis. Data were grouped into short-term (≤7 d) and long-term (>7 d) postoperative follow-up. Twenty-three of thirty-one studies involving 642 patients included in the systematic review were suitable for meta-analysis. Pooled data from the meta-analysis revealed a mean depletion of plasma vitamin C concentration of -17·99 µmol/l (39 % depletion) (CI -22·81, -13·17) (trial arms = 25, n 565, P < 0·001) during the first postoperative week and -18·80 µmol/l (21 % depletion) (CI -25·04, -12·56) (trial arms = 6, n 166, P < 0·001) 2-3 months postoperatively. Subgroup analyses revealed that these depletions occurred following different types of surgery; however, high heterogeneity was observed amongst trials assessing concentration change during the first postoperative week. Overall, our results warrant larger, long-term investigations of changes in postoperative plasma vitamin C concentrations and their potential effects on clinical symptomology.


Subject(s)
Ascorbic Acid , Vitamins , Humans , Prospective Studies
2.
Nutr Res Rev ; 32(1): 79-98, 2019 06.
Article in English | MEDLINE | ID: mdl-30378509

ABSTRACT

The proportion of adults aged 60 years and over is expected to increase over the coming decades. This ageing of the population represents an important health issue, given that marked reductions to cerebral macro- and microstructural integrity are apparent with increasing age. Reduced cerebral structural integrity in older adults appears to predict poorer cognitive performance, even in the absence of clinical disorders such as dementia. As such, it is becoming increasingly important to identify those factors predicting cerebral structural integrity, especially factors that are modifiable. One such factor is nutritional intake. While the literature is limited, data from available cross-sectional studies indicate that increased intake of nutrients such as B vitamins (for example, B6, B12 and folate), choline, n-3 fatty acids and vitamin D, or increased adherence to prudent whole diets (for example, the Mediterranean diet) predicts greater cerebral structural integrity in older adults. There is even greater scarcity of randomised clinical trials investigating the effects of nutritional supplementation on cerebral structure, though it appears that supplementation with B vitamins (B6, B12 and folic acid) or n-3 fatty acids (DHA or EPA) may be beneficial. The current review presents an overview of available research examining the relationship between key nutrients or adherence to select diets and cerebral structural integrity in dementia-free older adults.


Subject(s)
Aging , Brain/drug effects , Cognition/drug effects , Cognitive Dysfunction/prevention & control , Diet , Dietary Supplements , Aged , Aged, 80 and over , Choline/pharmacology , Choline/therapeutic use , Dementia/prevention & control , Fatty Acids, Omega-3/pharmacology , Fatty Acids, Omega-3/therapeutic use , Humans , Middle Aged , Polyphenols/pharmacology , Polyphenols/therapeutic use , Vitamins/pharmacology , Vitamins/therapeutic use
3.
Nutr Metab Cardiovasc Dis ; 26(5): 393-9, 2016 05.
Article in English | MEDLINE | ID: mdl-27105868

ABSTRACT

BACKGROUND AND AIMS: Progressive microvascular dysfunction in type 2 diabetes mellitus (T2DM) may impair the ability of cerebral vessels to supply blood to brain regions during local metabolic demand, thereby increasing risks of dementia. Having previously demonstrated that resveratrol can enhance vasodilator function in the systemic circulation, we hypothesised that resveratrol could similarly benefit the cerebral circulation. We aimed to determine the most efficacious dose of resveratrol to improve cerebral vasodilator responsiveness (CVR) in T2DM. METHODS AND RESULTS: In a double-blind, placebo-controlled, balanced crossover intervention, 36 dementia-free, non-insulin dependent T2DM older adults (49-78 years old) consumed single doses of synthetic trans-resveratrol (0, 75, 150, and 300 mg) at weekly intervals. Transcranial Doppler ultrasound was used to assess CVR to a hypercapnic stimulus, both before and 45 min after treatment. CVR, measured bilaterally in the middle cerebral arteries (MCA) and posterior cerebral arteries (PCA), was expressed as the percentage change in mean blood flow velocity from baseline to the peak velocity attained during hypercapnia. Resveratrol consumption increased CVR in the MCA; mean within-individual changes for each dose from placebo were 13.8 ± 3.5% for 75 mg (P = 0.001), 8.9 ± 3.5% for 150 mg (P = 0.016), and 13.7 ± 3.3% for 300 mg (P < 0.001); only the 75 mg dose was efficacious in the PCA (13.2 ± 4.5%, P = 0.016). CONCLUSIONS: Our results provide the first clinical evidence of an acute enhancement of vasodilator responsiveness in cerebral vessels following consumption of resveratrol in this population who are known to have endothelial dysfunction and sub-clinical cognitive impairment. Importantly, maximum improvement was observed with the lowest dose used. CLINICAL TRIAL REGISTRATION: ACTRN12614000891628 (www.anzctr.org.au).


Subject(s)
Cerebrovascular Circulation/drug effects , Cerebrovascular Disorders/prevention & control , Diabetes Mellitus, Type 2/drug therapy , Diabetic Angiopathies/prevention & control , Middle Cerebral Artery/drug effects , Posterior Cerebral Artery/drug effects , Stilbenes/administration & dosage , Vasodilation/drug effects , Aged , Blood Flow Velocity/drug effects , Cerebrovascular Disorders/diagnostic imaging , Cerebrovascular Disorders/etiology , Cerebrovascular Disorders/physiopathology , Cognition/drug effects , Cognition Disorders/etiology , Cognition Disorders/physiopathology , Cognition Disorders/prevention & control , Cognition Disorders/psychology , Cross-Over Studies , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/diagnosis , Diabetic Angiopathies/diagnostic imaging , Diabetic Angiopathies/etiology , Diabetic Angiopathies/physiopathology , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Male , Middle Aged , Middle Cerebral Artery/diagnostic imaging , Middle Cerebral Artery/physiopathology , Posterior Cerebral Artery/diagnostic imaging , Posterior Cerebral Artery/physiopathology , Resveratrol , Stilbenes/adverse effects , Time Factors , Treatment Outcome , Ultrasonography, Doppler, Transcranial , Victoria
4.
Age (Dordr) ; 37(3): 9782, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25903286

ABSTRACT

A number of randomised controlled trials have indicated that multivitamin/mineral supplementation for a period of 4 weeks or greater can enhance mood and cognition. To date, no studies have investigated whether a single multivitamin dose can benefit mental function in older adults. This study investigated the acute effects of a single multivitamin and mineral and herbal (MVMH) supplement versus placebo on self ratings of mood and the performance of an effortful computerised cognitive battery in a sample of 76 healthy women aged 50-75 years. Mood was assessed using the depression anxiety stress scale (DASS), state trait anxiety inventory-state anxiety scale and visual analogue scales (VAS). Mood was rated at 1 h post supplementation and again after the competition of the cognitive assessments at 2 h post supplementation. It was demonstrated that the MVMH supplement improved overall DASS mood ratings; however, the most prominent effects appeared to be a reduction in ratings of perceived mental stress. These findings were confirmed using visual analogue scales, with these measures also demonstrating MVMH-related increased ratings of calmness. There were no benefits of the MVMH to mood ratings of depression and performance was not enhanced on the cognitive battery. Supplementation with a single multivitamin, mineral and herbal supplement reduces stress several hours after intake in healthy older people.


Subject(s)
Affect/drug effects , Cognition/drug effects , Minerals/administration & dosage , Phytotherapy , Vitamins/administration & dosage , Aged , Dietary Supplements , Female , Humans , Middle Aged , Psychiatric Status Rating Scales
5.
Appetite ; 69: 123-36, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23727255

ABSTRACT

Previous research has suggested that multivitamin (MV) supplementation may be associated with beneficial effects for mood and general well-being, although treatment durations have typically been less than 90 days, samples have often been restricted to males only and acute effects have not been adequately differentiated from chronic effects. In the current study a MV supplement containing high levels of B-vitamins was administered daily to 138 healthy young adult participants between the ages of 20 and 50 years over a 16-week period. Chronic mood measures (GHQ-28, POMS, Chalder fatigue, PILL, Bond-Lader and custom visual analogue scales) were administered pre-dose at baseline, 8- and 16-weeks. Changes in Bond-Lader and VAS in response to a multi-tasking framework (MTF) were also assessed at 8- and 16-weeks. For a subset of participants, at-home mobile-phone assessments of mood were assessed on a weekly basis using Bond-Lader and VAS. No significant treatment effects were found for any chronic laboratory mood measures. In response to the MTF, a significant treatment x time interaction was found for STAI-S, with a trend towards a greater increase in stress ratings for male participants in the MV group at 16 weeks. However, this finding may have been attributable to a larger proportion of students in the male MV group. In contrast, at-home mobile-phone assessments, where assessments were conducted post-dose, revealed significantly reduced stress, physical fatigue and anxiety in the MV group in comparison to placebo across a number of time points. Further research using both acute and chronic dosing regimens are required in order to properly differentiate these effects.


Subject(s)
Affect/drug effects , Dietary Supplements , Health Status , Vitamins/administration & dosage , Adult , Anxiety/prevention & control , Cell Phone , Double-Blind Method , Fatigue/prevention & control , Female , Humans , Male , Middle Aged , Placebos , Stress, Psychological/prevention & control , Surveys and Questionnaires , Young Adult
6.
Phytother Res ; 27(11): 1605-13, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23280675

ABSTRACT

The efficacy and tolerability of current treatments for smoking cessation are relatively poor. More research is required to address the biological mechanisms underpinning nicotine withdrawal and drug treatments for smoking cessation. We assessed the neurocognitive effects of Remotiv® (Hypericum perforatum Special Extract - Ze 117), Nicabate CQ Nicotine Replacement therapy (NRT) and combined NRT/HP during conditions of smoking abstinence in 20 regular smokers aged between 18 and 60 years over a period of 10 weeks during smoking cessation. A Spatial Working Memory (SWM) task was completed at baseline, 4 weeks prior to quitting, as well as at the completion of the study, following the 10 weeks of treatment. Brain activity was recorded during the completion of the SWM task using Steady-State Probe Topography. Reaction time and accuracy on the SWM task were not found to be significantly different between treatment groups at retest. Differences in SSVEP treatment profiles at retest are discussed, including stronger SSVEP Amplitude increase in posterior-parietal regions for the HP and NRT groups and greater fronto-central SSVEP Phase Advance in the HP group.


Subject(s)
Hypericum/chemistry , Memory, Short-Term/drug effects , Plant Extracts/pharmacology , Reaction Time/drug effects , Smoking Cessation/methods , Adolescent , Adult , Drug Therapy, Combination , Humans , Middle Aged , Nicotine/therapeutic use , Plant Extracts/therapeutic use , Reproducibility of Results , Substance Withdrawal Syndrome/drug therapy , Young Adult
7.
Traffic Inj Prev ; 14(1): 13-7, 2013.
Article in English | MEDLINE | ID: mdl-23259514

ABSTRACT

OVERVIEW: Increasing concerns over the potentially impairing effects of prescriptive sedative drugs such as benzodiazepines on driving have been raised. However, other alternatives such as natural medicines may also carry similar risks with respect to driving safety. Kava (Piper methysticum) is a psychotropic plant commonly used both recreationally and medicinally in the United States, Australia, and the South Pacific to elicit a physically tranquilizing effect. To date no controlled study has tested a medicinal dose of kava versus placebo and a standard sedative drug on driving ability and driving safety. OBJECTIVE: Due to the need to establish the safety of kava in operating a motor vehicle, we compared the acute effects of the plant extract versus the benzodiazepine oxazepam and placebo using a driving simulator. METHODS: A driving simulator (AusEd) was used by 22 adults aged between 18 and 65 years after being randomly administered an acute medicinal dose of kava (180 mg of kavalactones), oxazepam (30 mg), or placebo one week apart in a crossover design trial. RESULTS: No impairing effects on driving outcomes were found after kava administration compared to placebo. Results on specific driving outcome domains revealed that the oxazepam condition had significantly slower braking reaction time compared to the placebo condition (p =.002) and the kava condition (p =.003). The kava condition had significantly fewer lapses of concentration compared to the oxazepam condition (p =.033). No significant differences were found between conditions for steering deviation, speed deviation, and number of crashes. Results were not modified by driving experience. On the Bond-Lader visual analogue sub-scale of alertness, a significant Treatment × Time interaction (p =.032) was found, with a significant reduction over time for oxazepam decreasing alertness (p <.001), whereas no significant reduction was found in the kava or placebo conditions. CONCLUSION: The results indicate that a medicinal dose of kava containing 180 mg of kavalactones does not impair driving ability, whereas 30 mg of oxazepam shows some impairment. Research assessing larger recreational doses of kava on driving ability should now be conducted.


Subject(s)
Automobile Driving/psychology , Hypnotics and Sedatives/adverse effects , Kava/adverse effects , Plant Extracts/adverse effects , Psychomotor Performance/drug effects , Adolescent , Adult , Aged , Computer Simulation , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Male , Middle Aged , Oxazepam/adverse effects , Young Adult
8.
Hum Psychopharmacol ; 27(5): 514-6, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22847648

ABSTRACT

OBJECTIVE: The current pilot study aimed to assess the effects of drinking alcohol in a naturalistic setting on aspects of performance. METHODS: Thirty individuals were approached and tested individually in a university campus bar. They provided details regarding alcoholic drinks consumption. Each was breathalysed before and after completion of a computerised test battery administered on a handheld device. The battery consisted of visual analogue mood scales, a series of alcohol-sensitive psychomotor and cognitive tests. RESULTS: There were highly significant correlations between measured blood alcohol concentrations, estimated units of alcohol consumed and scores on a 'sober-drunk' VAS (p < 0.001 in all cases). For performance, there was a characteristic alcohol-associated shift in the speed/accuracy trade-off (SATO), which was reflected as significantly more errors with less effect on speed across several measures (including maze performance and Serial Sevens). Individuals who were more intoxicated were also significantly less alert. CONCLUSIONS: The data suggest that controlled laboratory tests into the effects of alcohol intoxication may have ecological validity, with SATO shifts amongst the characteristic impairments seen in both controlled and naturalistic settings.


Subject(s)
Affect/drug effects , Alcohol Drinking/adverse effects , Ethanol/adverse effects , Psychomotor Performance/drug effects , Adolescent , Cognition/drug effects , Diagnosis, Computer-Assisted , Ethanol/administration & dosage , Ethanol/blood , Humans , Neuropsychological Tests , Pilot Projects , Young Adult
10.
Hum Psychopharmacol ; 27(3): 262-9, 2012 May.
Article in English | MEDLINE | ID: mdl-22311378

ABSTRACT

RATIONALE: Kava (Piper methysticum) is a psychotropic plant medicine with history of cultural and medicinal use. We conducted a study comparing the acute neurocognitive, anxiolytic, and thymoleptic effects of a medicinal dose of kava to a benzodiazepine and explored for the first time specific genetic polymorphisms, which may affect the psychotropic activity of phytomedicines or benzodiazepines. METHODS: Twenty-two moderately anxious adults aged between 18 and 65 years were randomized to receive an acute dose of kava (180 mg of kavalactones), oxazepam (30 mg), and placebo 1 week apart in a crossover design trial. RESULTS: After exposure to cognitive tasks, a significant interaction was revealed between conditions on State-Trait Anxiety Inventory-State anxiety (p = 0.046, partial ŋ² = 0.14). In the oxazepam condition, there was a significant reduction in anxiety (p = 0.035), whereas there was no change in anxiety in the kava condition, and there was an increase in anxiety in the placebo condition. An increase in Bond-Lader "calmness" (p = 0.002) also occurred for the oxazepam condition. Kava was found to have no negative effect on cognition, whereas a reduction in alertness (p < 0.001) occurred in the oxazepam condition. Genetic analyses provide tentative evidence that noradrenaline (SLC6A2) transporter polymorphisms may have an effect on response to kava. CONCLUSION: Acute "medicinal level" doses of this particular kava cultivar in naive users do not provide anxiolytic activity, although the phytomedicine also appears to have no negative effects on cognition.


Subject(s)
Anti-Anxiety Agents/therapeutic use , Anxiety , Cognition Disorders , Kava , Mood Disorders , Norepinephrine Plasma Membrane Transport Proteins/genetics , Oxazepam/therapeutic use , Phytotherapy/methods , Adolescent , Adult , Aged , Anxiety/complications , Anxiety/drug therapy , Anxiety/genetics , Cognition Disorders/drug therapy , Cognition Disorders/etiology , Cognition Disorders/genetics , Cross-Over Studies , Double-Blind Method , Female , Humans , Liver/drug effects , Liver/enzymology , Male , Middle Aged , Mood Disorders/drug therapy , Mood Disorders/etiology , Mood Disorders/genetics , Neuropsychological Tests , Plant Preparations/therapeutic use , Polymorphism, Genetic , Psychiatric Status Rating Scales , Young Adult
11.
Physiol Behav ; 105(4): 948-57, 2012 Feb 28.
Article in English | MEDLINE | ID: mdl-22120044

ABSTRACT

In a randomized, double-blind placebo controlled trial, 63 middle-aged volunteers aged between 40 and 65 years were administered a daily chocolate drink containing 250 mg or 500 mg cocoa flavanols versus a low cocoa flavanol (placebo) drink over a 30-day period. Participants were tested at baseline as well as at the end of the treatment period on a test of Spatial Working Memory. Steady State Probe Topography (SST) was used to assess neurocognitive changes associated with cocoa flavanol supplementation during the completion of the Spatial Working Memory task. SST is an electrophysiological technique which utilizes a 13 Hz diffuse visual flicker in order to generate a steady state visually evoked potential (SSVEP). Changes in the amplitude and phase of the SSVEP response after 30 days were compared between treatment groups. Behavioral measures of accuracy and reaction time were not found to be significantly different between treatment groups, while average SSVEP amplitude and phase differences at a number of posterior parietal and centro-frontal sites were found to be significantly different between groups during memory encoding, the working memory hold period and retrieval. In the absence of significant behavioral effects, these differences in brain activation can be interpreted as evidence of increased neural efficiency in spatial working memory function associated with chronic cocoa flavanol consumption.


Subject(s)
Beverages , Cacao , Evoked Potentials, Visual/drug effects , Flavonoids/pharmacology , Memory, Short-Term/drug effects , Nootropic Agents/pharmacology , Adult , Aged , Dose-Response Relationship, Drug , Double-Blind Method , Evoked Potentials, Visual/physiology , Female , Flavonoids/administration & dosage , Flavonols/pharmacology , Humans , Male , Memory, Short-Term/physiology , Middle Aged , Nootropic Agents/administration & dosage , Psychomotor Performance/drug effects , Psychomotor Performance/physiology , Reaction Time/drug effects , Reaction Time/physiology
12.
Hum Psychopharmacol ; 26(2): 102-11, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21437989

ABSTRACT

RATIONALE: Kava (Piper methysticum) elicits dose-dependent psychotropic effects and thus may potentially deleteriously affect cognitive performance. Clinical trials have assessed the effects of kava on cognition, however, to our knowledge no systematic review has been conducted in this area. OBJECTIVE: To systematically review the effects of kava on cognition, providing an analysis of the individual study's methodological quality, results and effect sizes. METHODS: A systematic review was conducted of publications up to June 15th 2010, using the electronic databases MEDLINE, PsychINFO, CINAHL, Web of Science and The Cochrane Library. The search criteria involved kava and cognition related terms, e.g. memory and attention. RESULTS: Ten human clinical trials met inclusion criteria (acute n = 7, chronic n = 3). One acute study found that kava significantly improved visual attention and working memory processes while another found that kava increased body sway. One chronic study found that kava significantly impaired visual attention during high-cognitive demand. Potential enhanced cognition may be attributed to the ability of kava to inhibit re-uptake of noradrenaline in the pre-frontal cortex, while increased body sway may be due to GABA pathway modulation. CONCLUSIONS: The majority of evidence suggests that kava has no replicated significant negative effects on cognition.


Subject(s)
Attention/drug effects , Cognition/drug effects , Kava , Plant Extracts/pharmacology , Animals , Attention/physiology , Clinical Trials as Topic/methods , Cognition/physiology , Humans , Phytotherapy/methods , Plant Extracts/chemistry , Plant Extracts/isolation & purification
13.
Neuropsychobiology ; 63(1): 15-21, 2011.
Article in English | MEDLINE | ID: mdl-20962543

ABSTRACT

AIMS: Our group has conducted several Internet investigations into the biobehavioural effects of self-reported recreational use of MDMA (3,4-methylenedioxymethamphetamine or Ecstasy) and other psychosocial drugs. Here we report a new study examining the relationship between self-reported Ecstasy use and traces of MDMA found in hair samples. METHODS: In a laboratory setting, 49 undergraduate volunteers performed an Internet-based assessment which included mood scales and the University of East London Drug Use Questionnaire, which asks for history and current drug use. They also provided a hair sample for determination of exposure to MDMA over the previous month. RESULTS: Self-report of Ecstasy use and presence in hair samples were consistent (p < 0.00001). Both subjective and objective measures predicted lower self-reported ratings of happiness and higher self-reported stress. Self-reported Ecstasy use, but not presence in hair, was also associated with decreased tension. CONCLUSION: Different psychoactive drugs can influence long-term mood and cognition in complex and dynamically interactive ways. Here we have shown a good correspondence between self-report and objective assessment of exposure to MDMA. These data suggest that the Internet has potentially high utility as a useful medium to complement traditional laboratory studies into the sequelae of recreational drug use.


Subject(s)
3,4-Methylenedioxyamphetamine/analogs & derivatives , Affect/drug effects , Hair/chemistry , Memory/drug effects , 3,4-Methylenedioxyamphetamine/analysis , 3,4-Methylenedioxyamphetamine/pharmacology , Adolescent , Adult , Female , Humans , Illicit Drugs/analysis , Illicit Drugs/pharmacology , Internet , Male , Marijuana Smoking/psychology , Self Medication , Self Report , Substance Abuse Detection , Surveys and Questionnaires
14.
Appetite ; 50(2-3): 506-13, 2008.
Article in English | MEDLINE | ID: mdl-18077056

ABSTRACT

Guaraná (Paullinia cupana) extracts are most commonly used in Western markets as putatively psychoactive food and drink additives. This double-blind, randomised, placebo-controlled, parallel groups study assessed the acute effects of either a vitamin/mineral/guaraná supplement or placebo drink in 129 healthy young adults (18-24 years). Participants completed a 10min version of the Cognitive Demand Battery (comprising: Serial 3s and Serial 7s subtraction tasks, a Rapid Visual Information Processing (RVIP) task, 'mental fatigue' scale). Thirty minutes following their drink participants made six consecutive completions of the battery (i.e. 60 min). The vitamin/mineral/guaraná combination resulted in improved task performance, in comparison to placebo, in terms of both increased speed and accuracy of performing the RVIP task throughout the post-dose assessment. The increase in mental fatigue associated with extended task performance was also attenuated by the supplement. This research supports previous findings demonstrating guaraná's cognition enhancing properties and provides evidence that its addition to a multi-vitamin-mineral supplement can improve cognitive performance and reduce the mental fatigue associated with sustained mental effort.


Subject(s)
Cognition/drug effects , Mental Fatigue/drug therapy , Paullinia/chemistry , Plant Extracts/pharmacology , Adolescent , Adult , Analysis of Variance , Cognition/physiology , Dietary Supplements , Double-Blind Method , Female , Humans , Male , Minerals , Neuropsychological Tests , Psychomotor Performance , Time Factors , Vitamins
15.
Hum Psychopharmacol ; 22(4): 199-210, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17457961

ABSTRACT

Recent data suggest that the complexation of standardised Ginkgo biloba extract (GBE) with soy-derived phospholipids enhances the bioavailability of GBE's active components. The current study therefore aimed to assess the comparative cognitive and mood effects of a low dose of GBE and products complexing the same extract with either phosphatidylserine or phosphatidylcholine. The study utilised a placebo-controlled, multi-dose, double-blind, balanced-crossover design. Twenty-eight healthy young participants received 120 mg GBE, 120 mg GBE complexed with phosphatidylserine (Virtiva), 120 mg GBE complexed with phosphatidylcholine and a matching placebo, on separate days 7 days apart. Cognitive performance was assessed using the Cognitive Drug Research (CDR) computerised test battery and Serial Subtraction tasks immediately prior to dosing and at 1, 2.5, 4 and 6 h thereafter. The primary outcome measures were the four aspects of cognitive performance, which have previously been derived by factor analysis of CDR subtests. Levels of terpenoids (bilobalide, ginkgolide A and ginkgolide B) were concomitantly assessed in plasma samples taken pre-dose and at 3 and 6.5 h post-dose.In keeping with previous research utilising the same methodology, 120 mg of GBE was not associated with markedly improved performance on the primary outcomes. However, administration of GBE complexed with phosphatidylserine resulted both in improved secondary memory performance and significantly increased speed of memory task performance across all of the post-dose testing sessions. Enhancement following GBE complexed with phosphatidylcholine was restricted to a modest improvement in secondary memory performance which was restricted to one post-dose time point. All three treatments were associated with improved calmness. There were no significant differences in post-dose levels of terpenoids between the Ginkgo containing treatments, although this latter finding may be attributable to methodological factors. Complexation with phosphatidylserine appears to potentiate the cognitive effects associated with a low dose of GBE. Further research is required to identify whether this effect is due to the complexation of the extracts, their mere combination, or the separate psychopharmacological actions of the two extracts.


Subject(s)
Cognition/drug effects , Ginkgo biloba/chemistry , Phosphatidylserines/pharmacology , Adult , Affect/drug effects , Attention/drug effects , Biological Availability , Chromatography, High Pressure Liquid , Cross-Over Studies , Double-Blind Method , Female , Humans , Male , Memory/drug effects , Memory, Short-Term/drug effects , Neuropsychological Tests , Phosphatidylserines/pharmacokinetics , Plant Extracts/pharmacokinetics , Plant Extracts/pharmacology , Psychomotor Performance/drug effects , Terpenes/blood
16.
J Psychopharmacol ; 21(1): 65-70, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16533867

ABSTRACT

The present study aimed to systematically assess acute, dose-related behavioural effects of an extract of guaraná plant for the first time in humans. This double-blind, counterbalanced, placebo-controlled study (n=26) assessed the acute mood and cognitive effects throughout the day of four different doses (37.5 mg, 75 mg, 150 mg and 300 mg) of a standardised guaraná extract (PC-102). Assessment included the Cognitive Drug Research computerized test battery and Bond-Lader mood scales. Guaraná improved secondary memory performance and increased alert and content mood ratings. The two lower doses produced more positive cognitive effects than the higher doses. This research supports previous findings of cognitive improvements following 75 mg guaraná and provides the first exploration of different dose effects of guaraná in humans. The findings suggest that the effects cannot be attributed to caffeine alone.


Subject(s)
Affect/drug effects , Caffeine/pharmacology , Cognition/drug effects , Psychotropic Drugs/pharmacology , Theobromine/pharmacology , Theophylline/pharmacology , Administration, Oral , Adult , Attention/drug effects , Caffeine/administration & dosage , Capsules , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Male , Memory/drug effects , Psychotropic Drugs/administration & dosage , Reference Values , Theobromine/administration & dosage , Theophylline/administration & dosage
17.
Br J Nutr ; 96(4): 639-42, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17010221

ABSTRACT

The results of two acute placebo-controlled, double-blind cross-over studies assessing the effect of Panax ginseng (G115) on blood glucose levels are reported. In study 1, thirty participants received three treatments: placebo; 200 mg G115; 400 mg G115. In study 2, twenty-seven participants received four treatments: placebo (0 mg ginseng and 30 mg saccharin); ginseng (200 mg ginseng and 30 mg saccharin); placebo-glucose (0 mg ginseng and 25 g oral glucose); ginseng-glucose (200 mg ginseng and 25 g oral glucose). Blood glucose levels were measured at baseline (at 09.00 hours after an overnight fast) and then 60, 90 (study 1 only) and 120 min post-dose. Both studies demonstrated that G115 alone significantly lowers fasting blood glucose levels. Conversely, in study 2 there was a significant drink x ginseng interaction suggesting opposing glycaemic effects of ginseng under fasting and raised blood glucose conditions. These data have implications for the use of ginseng in individuals with poor gluco-regulation.


Subject(s)
Blood Glucose/metabolism , Panax , Phytotherapy/methods , Adolescent , Adult , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Fasting/blood , Female , Glucose/pharmacology , Humans , Male , Plant Extracts/administration & dosage , Plant Extracts/therapeutic use
18.
Hum Psychopharmacol ; 21(5): 285-98, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16856221

ABSTRACT

BACKGROUND: Non-drug factors such as ambient temperature can heighten the adverse effects of MDMA (3,4-methylendioxymethamphetamine) in animals. We assessed whether dancing and feeling hot on Ecstasy would be associated with more psychobiological problems in recreational users. METHODS: In an internet study, 206 unpaid participants (modal age 16-24) reported that they had used recreational Ecstasy/MDMA. They completed a drug use questionnaire, the Prospective Memory Questionnaire (PMQ), questions about dancing and feeling hot when on Ecstasy, and psychobiological problems afterwards. RESULTS: Those who danced 'all the time' when on Ecstasy, reported significantly more PMQ memory problems than the less intensive dancers. Prolonged dancing was also associated with more complaints of depression, memory problems, concentration and organizational difficulties afterwards. Feeling hot when on Ecstasy was associated with poor concentration in the comedown period, and with mood fluctuation and impulsivity off-drug. PMQ long-term problems demonstrated a significant curvilinear relationship with thermal self-ratings; more memory problems were noted by those who felt very hot, and by those who did not feel hot when on Ecstasy. CONCLUSIONS: Non-drug factors such as dancing and feeling hot are associated with the incidence of psychobiological problems reported by recreational Ecstasy/MDMA users.


Subject(s)
Dancing , Hallucinogens/administration & dosage , Memory/drug effects , N-Methyl-3,4-methylenedioxyamphetamine/administration & dosage , Substance-Related Disorders , Thermosensing/drug effects , Adolescent , Adult , Chi-Square Distribution , Female , Humans , Male , Neuropsychological Tests , Psychiatric Status Rating Scales , Substance-Related Disorders/etiology , Substance-Related Disorders/physiopathology , Substance-Related Disorders/psychology , Surveys and Questionnaires
19.
J Psychopharmacol ; 20(3): 385-8, 2006 May.
Article in English | MEDLINE | ID: mdl-16574712

ABSTRACT

In recent years working memory deficits have been reported in users of MDMA (3,4-methylenedioxymethamphetamine, ecstasy). The current study aimed to assess the impact of MDMA use on three separate central executive processes (set shifting, inhibition and memory updating) and also on "prefrontal" mediated social and emotional judgement processes. Fifteen polydrug ecstasy users and 15 polydrug non-ecstasy user controls completed a general drug use questionnaire, the Brixton Spatial Anticipation task (set shifting), Backward Digit Span procedure (memory updating), Inhibition of Return (inhibition), an emotional intelligence scale, the Tromso Social Intelligence Scale and the Dysexecutive Questionnaire (DEX). Compared with MDMA-free polydrug controls, MDMA polydrug users showed impairments in set shifting and memory updating, and also in social and emotional judgement processes. The latter two deficits remained significant after controlling for other drug use. These data lend further support to the proposal that cognitive processes mediated by the prefrontal cortex may be impaired by recreational ecstasy use.


Subject(s)
Amphetamine-Related Disorders/diagnosis , Cognition Disorders/chemically induced , Emotions , Illicit Drugs/adverse effects , Judgment , N-Methyl-3,4-methylenedioxyamphetamine/adverse effects , Neuropsychological Tests , Social Perception , Substance-Related Disorders/diagnosis , Adolescent , Adult , Alcoholism/diagnosis , Alcoholism/psychology , Amphetamine-Related Disorders/psychology , Attention/drug effects , Cocaine-Related Disorders/diagnosis , Cocaine-Related Disorders/psychology , Cognition Disorders/diagnosis , Cognition Disorders/psychology , Drug Interactions , Emotions/drug effects , Female , Humans , Inhibition, Psychological , Male , Marijuana Abuse/diagnosis , Marijuana Abuse/psychology , Mental Recall/drug effects , Prefrontal Cortex/drug effects , Problem Solving/drug effects , Smoking/adverse effects , Substance-Related Disorders/psychology
20.
J Psychopharmacol ; 20(3): 437-46, 2006 May.
Article in English | MEDLINE | ID: mdl-16174668

ABSTRACT

Previous work provided preliminary evidence that different patterns of use among ecstasy users may impact on perceived side-effects. Participants recruited via an ecstasy-related bulletin board differed in their responses compared to those recruited via other means. The present investigation compares self-reports of psychobiological difficulties among ecstasy users recruited either via a bulletin board or by alternative methods. Qualitative data included reports of any negative or positive changes attributable to ecstasy use and reasons for cessation of use. An Internet-based design was utilized and 209 volunteers completed the study, 117 of whom were recruited via a bulletin board devoted to discussion of ecstasy. Psychobiological difficulties attributable to ecstasy use varied, with mood fluctuation the most common. Differences between the two groups in the extent to which these problems were reported was found. Bulletin board recruits were less likely to report anxiety or poor concentration, but more likely to report tremors/twitches. For the whole sample, lifetime use was associated more with psychobiologial problems, although this pattern was stronger and more pervasive for the non-bulletin board participants. Bulletin board recruits were more aware of possible negative psychological effects and were more likely to report adopting harm reduction strategies. From the qualitative data three negative consequences of use were identified, the most common of which was "psychological problems". In support of the quantitative findings the likelihood of reporting psychological problems increased with lifetime exposure to ecstasy in both recruitment conditions but interestingly this did not appear to impact on reasons for cessation of use. Participants also reported a number of effects that they regarded as beneficial. Future research should also take these aspects of use into account.


Subject(s)
Amphetamine-Related Disorders/complications , Attitude to Health , Illicit Drugs/adverse effects , Internet , N-Methyl-3,4-methylenedioxyamphetamine/adverse effects , Adolescent , Adult , Affect/drug effects , Amphetamine-Related Disorders/psychology , Attention/drug effects , Awareness , Female , Harm Reduction , Humans , Male , Memory/drug effects , Surveys and Questionnaires , Tics/chemically induced , Tics/psychology , Tremor/chemically induced , Tremor/psychology
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