Psychopharmacology (Berl). 2010 Oct;212(3):345-56. doi: 10.1007/s00213-010-1964-y. Epub 2010 Jul 31.
Effects of American ginseng (Panax quinquefolius) on neurocognitive function: an acute, randomised, double-blind, placebo-controlled, crossover study.
Scholey A*, Ossoukhova A, Owen L, Ibarra A, Pipingas A, He K, Roller M, Stough C.
Over the last decade, Asian ginseng (Panax ginseng) has been shown to improve aspects of human cognitive function. American ginseng (Panax quinquefolius) has a distinct ginsenoside profile from P. ginseng, promising cognitive enhancing properties in preclinical studies and benefits processes linked to human cognition.
The availability of a highly standardised extract of P. quinquefolius (Cereboost™) led us to evaluate its neurocognitive properties in humans for the first time.
This randomised, double-blind, placebo-controlled, crossover trial (N = 32, healthy young adults) assessed the acute mood, neurocognitive and glycaemic effects of three doses (100, 200 400 mg) of Cereboost™ (P. quinquefolius standardised to 10.65% ginsenosides). Participants’ mood, cognitive function and blood glucose were measured 1, 3 and 6 h following administration.
There was a significant improvement of working memory (WM) performance associated with P. quinquefolius. Corsi block performance was improved by all doses at all testing times. There were differential effects of all doses on other WM tasks which were maintained across the testing day. Choice reaction time accuracy and ‘calmness’ were significantly improved by 100 mg. There were no changes in blood glucose levels.
This preliminary study has identified robust working memory enhancement following administration of American ginseng. These effects are distinct from those of Asian ginseng and suggest that psychopharmacological properties depend critically on ginsenoside profiles. These results have ramifications for the psychopharmacology of herbal extracts and merit further study using different dosing regimens and in populations where cognition is fragile.
Hum Psychopharmacol. 2015 Mar;30(2):108-22. doi: 10.1002/hup.2463.
Improved working memory performance following administration of a single dose of American ginseng (Panax quinquefolius L.) to healthy middle-age adults.
Ossoukhova A*, Owen L, Savage K, Meyer M, Ibarra A, Roller M, Pipingas A, Wesnes K, Scholey A.
A ginsenoside-rich extract of American ginseng (Panax quinquefolius L.), Cereboost(TM), was previously shown to improve working memory and mood in healthy young individuals. The present study represented a partial replication investigating whether these effects extended to healthy middle-aged individuals.
Fifty-two healthy volunteers (40-60 years old, mean age 51.63) received 200 mg of P. quinquefolius or a matching placebo according to a double-blind, placebo-controlled, balanced, crossover design. The Cognitive Drug Research battery and the Computerised Mental Performance Assessment System were used to evaluate cognitive performance at baseline then 1, 3 and 6 h following treatment. Blood glucose and mood were co-monitored.
Compared with placebo, P. quinquefolius improved cognitive performance on ‘Working Memory’ factor at 3 h. Similar effects were observed in one of the two tasks making up this factor, spatial working memory. There were no significant effects on mood or blood glucose levels.
These data confirm that P. quinquefolius can acutely benefit working memory and extend the age range of this effect to middle-aged individuals. These changes are unlikely to be underpinned by modulation of blood glucose in this population.
Phytother Res. 2012 Aug;26(8):1166-72. doi: 10.1002/ptr.3700. Epub 2011 Dec 30.
HT1001, a proprietary North American ginseng extract, improves working memory in schizophrenia: a double-blind, placebo-controlled study.
Chen EY*, Hui CL.
Evidence suggests that HT1001™, a proprietary North American ginseng extract containing known levels of active ginsenosides, may improve cognitive function. Importantly, individuals with schizophrenia show marked deficits in working memory, which are believed to be predictive of functional outcome in this population. The present study aimed to characterize the effect of HT1001 on working memory in a group of stable individuals with schizophrenia. In a double-blind, placebo-controlled study design, a total of 64 individuals satisfying DSM-IV criteria for schizophrenia were randomly assigned to receive either HT100 or placebo for 4 weeks. Verbal working memory and visual working memory were assessed at baseline and again at the end of the treatment phase using the Letter-Number Span Test and Visual Pattern Test, respectively. Symptoms and medication side effects were also measured at baseline and post-treatment. Visual working memory was significantly improved in the HT1001 group, but not in the placebo group. Furthermore, extrapyramidal symptoms were significantly reduced after 4 weeks treatment with HT1001, whereas no difference in extrapyramidal effects was observed in the placebo group. These results provide a solid foundation for the further investigation of HT1001 as an adjunct therapy in schizophrenia, as an improvement in working memory and a reduction in medication-related side effects has considerable potential to improve functional outcome in this population.
Regul Toxicol Pharmacol. 2016 Jul;78:53-8. doi: 10.1016/j.yrtph.2016.04.006. Epub 2016 Apr 22.
Cereboost™, an American ginseng extract, improves cognitive function via up-regulation of choline acetyltransferase expression and neuroprotection.
Shin K, Guo H, Cha Y, Ban YH, Seo da W, Choi Y, Kim TS, Lee SP, Kim JC, Choi EK, Yon JM, Kim YB.
In Alzheimer disease (AD), amyloid-beta (Aβ) peptides induce the degeneration of presynaptic cholinergic system, in which decreased activity of enzyme choline acetyltransferase (ChAT) responsible for acetylcholine synthesis is observed. Cereboost™, an extract of American ginseng extract, contains a high concentration of Rb1 ginsenoside which is a well-known ingredient improving human cognitive function. We investigated the effects of Cereboost™ on learning and memory function of mice challenged with an Aβ1-42 peptide and the underlying mechanisms in vitro. Cereboost™ protected against Aβ1-42-induced cytotoxicity in F3.ChAT stem cells, and enhanced the ChAT gene expression. Aβ1-42 injection into the mouse brain impaired the cognitive function, which was recovered by oral administration of Cereboost™. In addition, Cereboost™ restored brain microtubule-associated protein 2 and synaptophysin as well as acetylcholine concentration. The results demonstrate that Cereboost™ administration recovered the cognitive function of AD model animals by enhancing acetylcholine level via ChAT gene expression and neuroprotection.