Piceatannol and resveratrol have the same basic parent structure with toluylene. The hydrogen atoms are substituted by hydroxy in different positions of benzene ring, then it becomes polyphenol. Studies show these compounds have obvious bioactivities of anti oxygenation, freeing radicals, protecting cardiovascular diseases and anti-cancer. 

Piceatannol mainly existent in grapes rhubarb moss, rhubarb and sugarcane. Its chemical formula is 3,4,3’,5’-TETRAHYDROXY-TRANS-STILBENE, C14H12O4. It has unstable chemical properties, it can be easily oxidized. The cis or trans configurations of natural piceatannol are inter-changeable. 

After the quick combination of reversal and glucose uronic acid derivatives, and it is transported in such form, and it disturbed in liver, spleen and other organs. Reversal in bound form can be easily entered through the blood-brain barrier. (Wang, 2002)

1. Scavenging oxygen radicals and antioxidant 

The over accumulation of reactive oxygen species radicals such as superoxide, hydroxyl radicals and hydrogen peroxide radicals, can damage organic component such as DNA, proteins and fat, which may lead to cancer, heart disease and cerebral hemorrhage and other diseases. Phenolic hydroxyls in piceatannol has effective anti oxygenation, and it can reduce the production of ROS by inhibiting the expression of inducible nitric oxide synthase and cyclooxyrgenase, so the glutathione level and superoxide dismutase can be recovered. It is able to eliminate and catch radicals to protect the damage from ROS among DNA and protein. 

2.  Anti-aging 

Aging is a complex life process. The oxidized unsaturated fatty acid in cell membrane lead to lipid per oxidation, and an inert waste-lipofuscin is cross linked and polymerized which is difficult to eliminate. The accumulation of this waste can hurt cells, and prevent the transmission of message and materials in cells. Lipofuscin accumulates into age pigments in skin cells. It can also accumulate in cardiac muscle cells which inhibits cardiac functions. The accumulation of lipofuscin in brain cells may decline memory and cause mental retardation, even lead to senile dementia. 

The cross linked collagen proteins reduce the elasticity and tightness of skin, wrinkle begins to increase, senile hyperosteogeny as well. Piceatannol and resveratrol can reduce the lipid per oxidation level and form of free radicals, and they can reduce the form of lipofuscin and damage of collagen. (Jefremov, 2007)

3. Anti-inflammatory 

Piceatannol has a positive effect on cue and chronic inflammation caused by ischemia, hurt and allergy. Noxious stimuli can increase ROS free radicals in body which may lead to change of regulation factors such as nuclear factor-κB, peroxisome proliferator-activated receptor, and signal transducer and activator of transcription. (Kim, 2007)

Piceatannol can inhibit the expression of certain genes which may lead to inflammation. 

It can restrain lipid per oxidation, release the vascular congestion of capillary, prevent the tissue degeneration and other inflammatory reactions. 

4. Anti-pathogenic microorganism 

Studies show piceatannol is broad spectrum anti-pathogenic microorganism, which has effective antibacterial activity for bacterias, epiphyte and virus. 

Piceatannol is able to disturb synthesis of staphylococcal cell wall, and damage cell membrane as well. It can disturb the synthesis in bacterias and affect cell growth and metabolism when the drug enter into thalli. The administration of piceatannol in cell wall leads to ionic balance disadjustment in cell, change of pH and osmotic pressure, and hurt matrix and organelle. 

And it has positive inhibition effect on SARS, H1N1 and other virus. 

5. Anticancer 

Piceatannol may has antiumous effect on initial stage, anti enzyme which help cancer grow, reproduction. It is able to disturb the message deliver and cell period in cells which may lead to 

apoptosis in cancer. (Yu, 2003)

6. Organ protective actions

Piceatannol can protective cardiovascular by reducing ischemia-reperfusion, morbidity and period of ventricular tachycardia and fibrillation, and vasodilative effects. It can prevent fat accumulation in cells and inhibit form of atherosclerotic plaque. It can inhibit platelet functions and expression of TF in endothelial cells. It can reduce atherosclerosis and promote vasodilative effects . 

Piceatannol is also able to protect brain cells, anti brain cell damage made by I/R and spinal cord injury. Prevent Parkinson’s disease and Alzheimer’s disease. 

Piceatannol can protect liver cells damaged by CCl4, obviously reduce liver fibrosis caused by CCl4. 

Piceatannol can promote the cell differentiation and proliferation from bone mesenchymal stem cells to osteoblasts cells. 

7. Immunomodulation

Piceatannol has good immunomodulatory effect on specific and unspecific reaction. It can obviously improve myocarditis, ostarthritis, and other diseases. The immunomodulation of piceatannol has a double effect, and dose correlation. 

Safety and dose:

After administration of resveratrol, it will absorbed in intestine in form of glucuronic acid, plasma concentrations attained peak in half an hour altering taking drugs, and recover in 2 hours. 

Liver is the main organ of reversal metabolism which is mainly phase II metabolisms. (Wenzel, 2005)The metabolites can be excreted via the urine, and can be eliminated quickly, which can not be accumulated easily. 

Piceatannol’s  50% inhibiting concentration of gonococcus and neisseria meningitis are 25 and 100 μg/mL, which is the best inhibition effect.

Reference:

Jefremov V, Zilmer M, Zilmer K, et al. Antioxidative effects of plant polyphenols: from protection of G protein signaling to prevention of age-related pathologies.[J]. Annals of the New York Academy of Sciences, 2007, 1095(1):449-57.

Kim J B, Han A R, Park E Y. Inhibition of LPS-induced iNOS, COX-2 and cytokines expression by poncirin through the NF-kappaB inactivation in RAW 264.7 macrophage cells.[J]. Biological & Pharmaceutical Bulletin, 2007, 30(12):2345-2351.

Wang Q, Xu J, Rottinghaus G E, et al. Resveratrol protects against global cerebral ischemic injury in gerbils[J]. Brain Research, 2002, 958(2):439-47.

Wenzel E, Soldo T, Erbersdobler H, et al. Bioactivity and metabolism of trans -resveratrol orally administered to Wistar rats[J]. Molecular Nutrition & Food Research, 2005, 49(5):482-94.

Yu C, Shin Y G, Kosmeder J W, et al. Liquid chromatography/tandem mass spectrometric determination of inhibition of human cytochrome P450 isozymes by resveratrol and resveratrol-3-sulfate[J]. Rapid Communications in Mass Spectrometry, 2003, 17(4):307-13.