Description
7,8-Dihydroxyflavone(7,8-DHF) is a naturally occurring flavone found in the tree Godmania aesculifolia. It is a selective tyrosine kinase receptor B(TrkB) agonist that has neurotrophic effects in various neurological diseases such as stroke and Parkinson's disease. 7,8-Dihydroxyflavone binds to the TrkB receptors in a similar way to BDNF, or brain derived neurotrophic factor. When the TrkB receptor is activated, neuroprotective and neurogenetive effects occur in neurons, which tend to affect the dendrites. Dendrites are what reach out from the neurons into the synapse to participate in signaling with other neurons. 7,8-DHF has been shown to promote the growth of these dendrites, and to help restore communication between neurons in animal models.
Chemical Properties
White crystalline powder or Yellow Solid, soluble in methanol, ethanol, DMSO and other organic solvents, from the dried root of Pulsatilla chinensis (Bge.) Regel.
Uses
7,8-Dihydroxyflavone is disubstituted flavone that acts as a small-molecule TrkB agonist. 7,8-Dihydroxyflavone has been shown to reverse memory deficits and BACE1 elevation in a mouse model of Alzheimer''s disease. 7,8-Dihydroxyflavone may also provide a therapeutic option in the treatment of other neorological disorders such as Rett syndrome and PTSD. It has recently been shown to counteract the inhibition of NMDA receptor caused by lead poisoning and confer protective effects in live rats.
Definition
ChEBI: 7,8-dihydroxyflavone is a dihydroxyflavone that is flavone substituted by hydroxy groups at positions 7 and 8. A dihydroxyflavone that is flavone substituted by hydroxy groups at positions 7 and 8. A naturally occurring flavonoid produced by several plants, including the weed Tridax procumbens (coalbuttons or tridax daisy) and the tree Godmania aesculifolia, In animal models, it has shown efficacy against several diseases of the nervous system, including Alzheimer's, Parkinson's, and Huntington's. It has a role as a plant metabolite, a tropomyosin-related kinase B receptor agonist, an antidepressant, an antioxidant and an antineoplastic agent.
Biological Activity
7,8-Dihydroxyflavone (7,8-DHF) is a monophenolic flavone with diverse effects. It acts as an agonist of the neurotrophic tyrosine kinase receptor TrkB (Kd = 320 nM), protecting neurons that express TrkB from apoptosis. 7,8-DHF is neuroprotective in an animal model of Parkinson’s disease. It supports emotional learning in mice and reverses memory deficits in a mouse model of Alzheimer’s disease. It also improves motor function and extends survival in an animal model of Huntington’s disease. 7,8-DHF inhibits the cytochrome P450 aromatase (IC50 = 10 μM) and, in this way, alters estrogen metabolism. It also has antioxidant action that increases intracellular glutathione synthesis and scavenges reactive oxygen species.
Biochem/physiol Actions
7,8-Dihydroxyflavone is a selective tyrosine kinase receptor B (TrkB) receptor agonist. It manifests all the therapeutic effects of brain-derived neurotrophic factor (BDNF)—such as protecting neurons from apoptosis, inhibiting kainic acid-induced toxicity, decreasing infarct volumes in stroke, and neuroprotecting in an animal model of Parkinson′s disease—without the poor pharmacokinetic profile of BDNF limiting its therapeutic potential.
Side effects
As with any other drug, 7,8-DHF is not without its side effects. However, there are not as many side effects associated with the use of 7,8-DHF as it is a natural product.
The following are some reported side effects associated with the use of 7,8-DHF or products that contain it:
Overstimulation
Restlessness
Dizziness
Nausea
Irritability
Trouble sleeping
target
TNF-α | MMP(e.g.TIMP) | ROS | HO-1 | p38MAPK | SOD | Akt | cAMP | HIF | PPAR | Calcium Channel
Mode of action
7,8-Dihydroxyflavone (7,8-DHF, tropoflavin) is the most common and effective flavone identified in Sophora plants.
7,8-DHF mimics the effects of brain-derived neurotrophic factor (BDNF) in brain cells by activating tropomyosin-related kinase B (TrkB) receptors, the typical target of BDNF.
The therapeutic potential of BDNF is restricted due to its short half-life (less than 10 minutes) and its inability to cross the blood-brain barrier because of its large size. Unlike BDNF 7,8-DHF is able to penetrate the blood-brain barrier and enter the central nervous system (CNS) .
7,8-DHF also increases the production of Nrf2. Nrf2 increases antioxidants enzymes such as heme oxygenase 1 (HO-1) and also enzymes that repair DNA (8-oxoguanine DNA glycosylase-1 – OGG1) .
References
1) Jang et al. (2010), A selective TrkB agonist with potent neurotrophic activities by 7,8-dihydroxyflavone; Proc. Natl. Acad. Sci. USA, 107 2687
2) Liu et al. (2014) Biochemical and biophysical investigation of the brain-derived neurotrophic factor mimetic 7,8-dihydroxyflavone in the binding and activation of the TrkB receptor; J. Biol. Chem., 289 27571
3) Jiang et al. (2013) Small-molecule TrkB receptor agonist improve motor function and extend survival in a mouse model of Huntington’s disease; Hum. Mol. Genet., 22 2462
4) Zhao et al. (2016) Post-injury Treatment of 7,8-Dihydroxyflavone Promotes Neurogenesis in the Hippocampus of the Adult Mouse; J. Neurotrauma, 33 2055
5) Korkmaz et al. (2014) 7,8-dihydroxyflavone improves motor performance and enhances lower motor neuronal survival in a mouse model of amyotrophic lateral sclerosis; Neurosci. Lett., 566 286
