Antioxidants neuroprotective properties

Flavonoids in the diet have been widely promoted as important antioxidant contributors. Their neuroprotective properties, because of this effect, have been demonstrated by several workers. However, they have also been demonstrated to have MAOI activity and this has been proposed as part of the explanation of the use of the common herb, St Johns Wort, Hypericum perforatum L., as an antidepressant. This dual role has now been proposed for a variety of flavonoids, such as kaempferol (22) from the leaves of Ginkgo biloba L., a widely used herbal product which has been suggested as a preventative agent against neurodegeneration. Quercetin (23), similarly, has also shown to inhibit MAO-B " and reverse the effects of induced catalepsy, which mimics the bradykinesia associated with PD. Tangeretin (24) also inhibits MAO-B and crosses the blood brain barrier in a rat model. 

The mechanism of how lowering cholesterol affects beta amyloid production is still unclear studies have demonstrated that statins do not alter beta amyloid morphology (Hoglund et al., 2004). It may be that the neuroprotective properties of statins are due to antioxidant and anti-inflammatory effects. 

Moosmann, B., and Behl, C. (1999) The antioxidant neuroprotective effects of estrogens and phenolic compounds are independent from their estrogenic properties. Proc Natl Acad Sci U S. 4 96,... 

It has beat proposed that possible mechanisms underlying the neuroprotective and/or neurotrophic properties of EGb in the CNS indude influences on neurotransmitters, energy metabolism and membrane functions, as well as antioxidant activities and inhibition of platelet-activation factor (PAF). 

Neuroprotective Action of EGCG Does Not Involve Its Antioxidant Properties... 

Stobadine ((-)-cis-2,8 dimethyl-2,3,4,4a,5,9b-hexahydro-l-H-pyrido (4,3b) indole) is a model drug with pyridoindole structure with cardioprotective and antioxidant properties [109]. Based on stobadine, (-)-ris-2,8-dimethyl-2,3,4,4a,5,9b-hexahydro-lH-pyrido[4,3-b]indole (Fig. 4), a well-known antioxidant, free-radical scavenger and neuroprotectant, stobadine derivatives with improved pharmacodynamic and toxicity profiles were developed [110]. A stobadine molecule was modified mostly by electron donating substitution on the benzene ring and by alkoxycarbonyl substitution at N-2 position. Significant antioxidant activity was observed in the new compounds. A link... 

Biochanin-A is a potent phytoconstituent which has been used in India as an antitumor, a dopaminergic neuron protective agent, an antioxidant, an anticholinergic and a neuroprotectant with antioxidant properties, anticholinesterase activity, and neurotransmitter (noradrenalin, dopamine) enhancing capacity [215]. 

Lastres-Becker 1, Molina-Holgado F, Ramos JA, Mechoulam R, Fernandez-Ruiz J (2004a) Cannabinoids provide neuroprotection in experimental models of Parkinson s disease involvement of their antioxidant properties and/or of glial cell-mediated effects. Neurobiol Dis (in press)... 

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