Gingko – A Traditional Medicine
The seeds and leaves of Ginkgo biloba are used in traditional medicines. The two main bioactive constituents present in a concentrated standardized extract of Ginkgo biloba are Flavonoid Glycosides (24%) and terpene lactones (6%), which may act in a complementary manner. These molecules act as antioxidants/free radical scavengers, enzyme inhibitors, and cation chelators (1). The therapeutic mechanisms of action of the Ginkgo leaf extract are suggested to be through its antioxidant, antiplatelet, anti-hypoxic, anti-edemic, Hemorheology, and microcirculatory actions. Studies conducted shows that there is a significant improvement in speed of information processing in the brain related to working memory. The bioactive constituents from the Ginkgo biloba have the potential to act as a ‘smart drug’ or nootropic agent to improve intelligence (3).
Mechanism of Action
The Ginkgo leaf extract has been reported to have the therapeutical role in neurodegenerative disease prevention and enhancing mental health (stress release and memory enhancing action) (2):
- Inhibit the formation of Aβ from β-amyloid precursor protein (APP), a crucial process in the pathogenesis of Alzheimer’s disease
- Inhibits ROS accumulation induced by Aβ (particularly flavonol quercetin) and also reduces neuron apoptosis, where apoptosis is considered to be one of the main causes for neurodegenerative diseases and thus help to relieve Alzheimer’s disease
- Improve cerebral blood flow by stimulating Norepinephrine secretion
- Anxiety syndromes such as stress, moods, and depression are becoming common in the modern world. 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
- 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
- Decrease the corticosteroid synthesis and subsequently the circulating levels of glucocorticoids
- The memory enhancing effects of Ginkgo leaf extract is through prevention of neuron degeneration
Side effects
A transient headache has been documented as a side effect. The use of GBE has not been associated with other severe side effects to date. The whole plant, seeds, and pulp are occasionally associated with severe allergic reactions. Patients taking aspirin should exercise caution when adding GBE therapy (1).
References
1. Kleijnen J, Knipschild P. Ginkgo biloba. Lancet 1992; 340: 1136
2. Mahadevan, S., and Y. Park. “Multifaceted therapeutic benefits of Ginkgo biloba L.: Chemistry, efficacy, safety, and uses.” Journal of Food Science 73.1 (2008): R14-R19.
3. Stough, Con, et al. “Neuropsychological changes after 30-day Ginkgo biloba administration in healthy participants.” International Journal of Neuropsychopharmacology 4.2 (2001): 131-134.