“Stress‐alleviating” and “vigilance‐enhancing” actions of Ginkgo biloba extract (EGb 761)

Abstract

This overview is focused on the stress-alleviating and vigilance-enhancing properties of Ginkgo biloba extract (EGb 761) that have been observed in animal models and in humans and that appear useful in explaining the therapeutic effects of the extract on non-cognitive brain functions that may be reflective of mood changes. With regard to its stress-alleviating activity, in rodents EGb 761 facilitates behavioral adaptation, decreases circulating levels of corticosterone, catecholamines, ACTH, and CRH, suppresses the expression of the mitochondrial peripheral benzodiazepine receptor of the adrenal cortex, increases the anxiolytic activity of diazepam, increases arousal by an action that may involve GABA A receptor antagonism, induces anxiolytic-like activity, prevents stress-induced desensitization of hippocampal 5-HT 1A receptors, suppresses the down-regulation of hippocampal glucocorticoid receptors, and facilitates decision-making. In humans, EGb 761 has vigilance-enhancing effects that support its clinical use in treating disorders involving stress-induced brain dysfunction and those non-cognitive symptoms of dementia currently classified as ''behavioral and psychological symptoms of dementia'' (BPSD). Collectively, these findings indicate that EGb 761 is useful for treating symptoms that are now classified as components of BPSD. As drug combinations consisting of EGb 761 and a non-selective cholinesterase inhibitor, an antidepressant drug, or a neuroleptic could possibly be even more useful in treating BPSD, evaluation of such therapy is recommended. Drug Dev.

Modulation of cognitive performance following single doses of 120 mg Ginkgo biloba extract administered to healthy young volunteers

“…Given the complicated pattern of effects seen on attention task performance, with slowing seen here for 120 mg, but faster performance seen to increase with dose for 240 and 360 mg previously (Kennedy et al, 2000) a potential mechanism that might accommodate complicated behavioural response such as this would be modulation of neurotransmitter synthesis and/or functionality. To this end Ginkgo has been shown to interact with adrenergic, cholinergic, dopaminergic, glutamatergic, serotonergic and GABAergic parameters (for reviews see Ahlemeyer and Krieglstein, 2003;DeFeudis and Drieu, 2004). However, this possibility does not preclude a behavioural influence of any of the wide range of other microscopic cellular effects exerted by Ginkgo or their concordant modulation of physiological parameters.…”

“…and Krieglstein, 2003;Ahmad et al, 2005;DeFeudis and Drieu, 2004;Lee et al, 2004;Shah et al, 2003), beneficial effects on blood circulation (e.g. Ahlemeyer and Krieglstein, 2003;Chung et al, 1999;Jung et al, 1990;Koltringer et al, 1993;Krieglstein et al, 1986;Santos et al, 2003;Topp et al, 2001), with the latter including increased cerebral perfusion in humans (Santos et al, 2003).…”

Antioxidant Activity and Fatty Acid Composition of Ginkgo Biloba From Turkey

“…In recent years, use of herbal medicine in many countries is widely getting increase. National survey in the U.S.A. revealed that 18% of surveyed adults reported concomitant use of herbal medicines or high-dose vitamins with prescription medications (Feudis and Drieu 2004). Globally, one of the largest selling herbal supplements was standardized extract of Ginkgo leaves, EGB 761 on the markets.…”

Multifaceted Therapeutic Benefits of Ginkgo biloba L.: Chemistry, Efficacy, Safety, and Uses

“…Stress involves a rise in the levels of glucocorticoids, and a subsequent memory dysfunction, increased anxiety, decreased immunity, gastrointestinal tract disturbances, myocardial infarction, or effects such as increased vigilance (Walesiuk and others 2005). Since mood and emotion are related to stress, the alleviating effects of Ginkgo leaf extract may result in improving mood, thus resulting in antidepressant activity (DeFeudis and Drieu 2004).…”