March 3, 2015

Ginkgo biloba is one of the most widely used herbs in natural medicine. The idea that it can help improve cognitive function is far from new. However, new research is shedding light on how ginkgo works in the body and suggesting new uses for this fascinating herb.

It has long been known that ginkgo biloba increases blood flow to the brain. However, that in and of its self is not sufficient to explain the clinical benefits of its supplementation. In mouse models ginkgo decreases oxidative damage in brain tissues and increased levels of brain derived neurotropic factor, a protein necessary for nerve health.[1] Similarly, a study looking at the oxidative damage and apoptosis triggered by beta-amyloid in mouse hippocampal cells showed that a ginkgo extract could inhibit the creation of reactive oxygen species and the activation of caspace-3 thus inhibiting cell death.[2] Another new study provided evidence that bilobalide provides neuroprotective effects that help prevent reperfusion injuries by down regulating the expression of inflammatory mediators and decreasing programmed cell death.[3] In the peripheral nervous system ginkgo has been shown to increase nerve repair and neovascularization in experimental models of nerve damage.[4]

Beyond ginkgo’s traditional uses newer research is showing that ginkgo may have a role in managing blood lipids and blood sugar. In a recent German study on patients with metabolic syndrome, two months of treatment with a ginkgo extract led to significant decreases in C-reactive protein levels (by 44.4%) and insulin resistance. The authors also noted a decrease in the formation of nano-plaques.[5] Ginkgo appears to also protect and restore insulin sensitivity and signaling pathways in type 2 diabetes. It also decreased food intake, body fat and blood lipids in this particular study.[6] In models of plaque formation ginkgo has been shown to decrease the pro-inflammatory effects of oxidized low density lipoprotein and decrease matrix metalloproteinases in blood vessel endothelial cells.[7]

Safety is always a concern when putting a substance in your body. A recent meta-analysis of existing data found “that G. biloba extract is well tolerated and safe for humans.”[8] Newer research is confirming what has long been known in practice, that ginkgo is a safe and effective herb for improving nervous system health and cognitive function. It also supports the emerging use of this herb in the management of insulin-sensitivity and cardiovascular health.

References

  • [1] Behav Brain Res. 2014 Oct 30;278C:453-461. doi: 10.1016/j.bbr.2014.10.032.
    The effects of Ginkgo biloba extract on cognitive functions in aged female rats: The role of oxidative stress and brain-derived neurotrophic factor.
    Belviranlı M1, Okudan N2.
  • [2] Zhongguo Zhong Xi Yi Jie He Za Zhi. 2014 Jul;34(7):833-8.
    [Ginkgo biloba extract 50 inhibited beta-amyloid-induced oxidative stress in rats' hippocampal neurons: an experimental study].
    Xia CY, Dong XW, Zhao Y, Xu Y, Hao L, Zhang ZX.
  • [3] J Neuroinflammation. 2014 Sep 26;11(1):167.
    Neuroprotective effects of bilobalide on cerebral ischemia and reperfusion injury are associated with inhibition of pro-inflammatory mediator production and down-regulation of JNK1/2 and p38 MAPK activation.
    Jiang M, Li J, Peng Q, Liu Y, Liu W, Luo C, Peng J, Li J, Yung K, Mo Z.
  • [4] Cell Mol Neurobiol. 2014 Oct 16.
    Ginkgo Biloba Extract (EGb 761) Promotes Peripheral Nerve Regeneration and Neovascularization After Acellular Nerve Allografts in a Rat Model.
    Zhu Z1, Zhou X, He B, Dai T, Zheng C, Yang C, Zhu S, Zhu J, Zhu Q, Liu X.
  • [5] Atherosclerosis. 2014 Dec;237(2):584-8. doi: 10.1016/j.atherosclerosis.2014.10.023. Epub 2014 Oct 18.
    Combined lowering of low grade systemic inflammation and insulin resistance in metabolic syndrome patients treated with Ginkgo biloba.
    Siegel G1, Ermilov E2, Knes O3, Rodríguez M4.
  • [6] Braz J Med Biol Res. 2014 Sep;47(9):780-8. Epub 2014 Jul 25.
    Beneficial effects of Ginkgo biloba extract on insulin signaling cascade, dyslipidemia, and body adiposity of diet-induced obese rats.
    Banin RM1, Hirata BK1, Andrade IS2, Zemdegs JC2, Clemente AP3, Dornellas AP2, Boldarine VT2, Estadella D4, Albuquerque KT5, Oyama LM2, Ribeiro EB2, Telles MM1.
  • [7] J Vasc Surg. 2014 Jul 28. pii: S0741-5214(14)01124-0. doi: 10.1016/j.jvs.2014.05.098.
    Ginkgo biloba extract inhibits oxidized low-density lipoprotein (oxLDL)-induced matrix metalloproteinase activation by the modulation of the lectin-like oxLDL receptor 1-regulated signaling pathway in human umbilical vein endothelial cells.
    Tsai KL1, Chang YL2, Huang PH3, Cheng YH2, Liu DH4, Chen HY5, Kao CL6.
  • [8] Toxicology. 2015 Jan 2;327C:95-115. doi: 10.1016/j.tox.2014.10.013. Epub 2014 Nov 11.
    Cross matching observations on toxicological and clinical data for the assessment of tolerability and safety of Ginkgo biloba leaf extract.
    Heinonen T1, Gaus W2.