5 replies to this topic

[Tom Andre F. (ex shinobi)]

Hello everyone,

 

First sorry again for my english.

 

I lunched a blog (with some help, thanks to them) to speak only about pterostilbene that you can visit here: http://www.pterostilbene.com

 

I did a topic about pterostilbene pharmacokinetics that you can read. But now im interested by knowing anything about the important metabolites, mainly piceatannol

 

We know that it is the most active metabolite of resveratrol (especially due to the half life following resveratrol consumption and due to the very high SIRT1 activity) . It is a a by product in vivo of resveratrol though its hydroxylation by CYP1B1 (which is over-expressed in a wide range of human tumors because it is a tumor-suppressing enzyme)

 

Here is a private reply by Maxwatt about this topic (and this study:  http://www.ncbi.nlm....ubmed/15276085)he allow me to post his reply so here we go:

 

"Pterostilbene is methoxylated resveratrol.  By comparison, codeine is methoxylated morphine.  Similar, but different effects.  And slightly different metabolic pathways.  I don't know enough about the pharokinetics of pterostilbene, though it is probably more bioavailabe than resveratrol, the effects may be slightly different.  I don't think it necessarily breaks down into piceatenol, or an analog.  If the particular CYP450 enzyme that mediates the process is rate limiting, using piceatenol would be more potent is some respects.  Interestingly, one of the other products they refer to as M1 is tetrahydroxystilbene, found it Polygonum multiflorum (Chinese herb He Shou Wu) traditionally used to restore grey hair to black. To my knowledge, it doesn't, nor does resveratrol to any great degree.  But tetrahydroxystilbene prevents AGE formation, and possibly according to one paper in Chinese, breaks the AGE bond. I had no idea it was a metabolite of resveratrol!"

 

We have also

 

However I do not remember why I noticed direct supplementation with piceatannol is not a good idea. I think it was due to the stability of the molecule, Im not sure and I try to found back all information about that. On the other hand, I think piceatannol is also a metabolite of pterostilbene. Pterostilbene is very close of resveratrol, and the bio mechanism looks very similar.

 

Also if anyone has access to this study : http://www.ncbi.nlm....ubmed/17132206 we can check the oral concentration of piceatannol, the bioavailability seems very low. Another study which should be helpful: http://www.ncbi.nlm....pubmed/18666380

 

Any help on the topic ?

 

 

 

 

Edited by Tom Andre F. (ex shinobi), 17 April 2015 - 04:13 PM.

[Logic]

As I understand it 2,3,5,4'- tetrahydroxystilbene is the AGE breaker Maxwatt?
Is M1 close enough to have the same effect?

 

...Using HPLC analysis with fluorescence detection we observed the formation of two major metabolites (M1 and M2) and one minor metabolite M3 (Figure 2A). The major metabolite M2 has been identified as piceatannol (3,4,3′,5′-tetrahydroxystilbene). The other metabolites M1 and M3 have not been conclusively identified due to the unavailability of authentic standards. However we have deduced that M1 is probably 3,4,5,4′-tetrahydroxystilbene which results from 4-hydroxylation of the other aromatic ring, whilst M3 is possibly the corresponding dihydroxylated metabolite 3,4,5,3′,4′-pentahydroxystilbene. It is interesting to note here the striking similarity in molecular structure of these two putative metabolites to the structure of the highly potent anticancer agent Combretastatin A4 (3-hydroxy-4,3′,4′,5′-tetramethoxystilbene) (Dark et al, 1997). The other major metabolite M1 has been tentatively assigned here as 3,4,5,4′-tetrahydroxystilbene, and this stilbene has very recently been reported as an analogue of resveratrol that induces apoptosis in transformed cells, but not in their normal counterparts...

http://www.nature.co...l/6600197a.html

 

2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (THSG), a natural product purified from the Chinese medical herb Polygoni multiflori Radix, has been demonstrated to possess many pharmacological activities, including antioxidant, anti-inflammatory, hepatoprotective and antitumor properties...

...The concentrations of the THSG in rat plasma, bile and urine or faeces samples were determined by HPLC-UV. The results show THSG was rapidly absorbed within 30 min in plasma. Absolute bioavailability of THSG was 40%. Total recovery of unchanged THSG within 24 h were low (0.041% in bile, 0.06% in faeces), whereas the amount of unchanged THSG excreted in the urine within 24 h was lower than LLOQ.

https://www.research...metry_and_high_

 

This study found that 2,3,5,4'-tetrahydroxystilbene 2-O-beta-D-glucoside (THSG), the major bioactive compound from Polygonum multiflorum Thunb., can efficiently inhibit the formation of AGEs in a dose-dependent manner by trapping reactive MGO under physiological conditions (pH 7.4, 37 degrees C). More than 60% MGO was trapped by THSG within 24 h, which was much more effective than resveratrol and its methylated derivative, pterostilbene, the two major bioactive dietary stilbenes.

http://www.ncbi.nlm....pubmed/20104848

 

 

[Logic]

deleted

Edited by Logic, 14 January 2016 - 03:47 AM.

[maxwatt]

 M1 IS 2,3,5,4'- tetrahydroxystilbene.

I looked diligently for this substance, because of the positive reports of its effects.  Then discovering it is a major metabolite of resveratrol, I just take more resveratrol. 

 

 

As I understand it 2,3,5,4'- tetrahydroxystilbene is the AGE breaker Maxwatt?
Is M1 close enough to have the same effect?

 

...Using HPLC analysis with fluorescence detection we observed the formation of two major metabolites (M1 and M2) and one minor metabolite M3 (Figure 2A). The major metabolite M2 has been identified as piceatannol (3,4,3′,5′-tetrahydroxystilbene). The other metabolites M1 and M3 have not been conclusively identified due to the unavailability of authentic standards. However we have deduced that M1 is probably 3,4,5,4′-tetrahydroxystilbene which results from 4-hydroxylation of the other aromatic ring, whilst M3 is possibly the corresponding dihydroxylated metabolite 3,4,5,3′,4′-pentahydroxystilbene. It is interesting to note here the striking similarity in molecular structure of these two putative metabolites to the structure of the highly potent anticancer agent Combretastatin A4 (3-hydroxy-4,3′,4′,5′-tetramethoxystilbene) (Dark et al, 1997). The other major metabolite M1 has been tentatively assigned here as 3,4,5,4′-tetrahydroxystilbene, and this stilbene has very recently been reported as an analogue of resveratrol that induces apoptosis in transformed cells, but not in their normal counterparts...

http://www.nature.co...l/6600197a.html

 

2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (THSG), a natural product purified from the Chinese medical herb Polygoni multiflori Radix, has been demonstrated to possess many pharmacological activities, including antioxidant, anti-inflammatory, hepatoprotective and antitumor properties...

...The concentrations of the THSG in rat plasma, bile and urine or faeces samples were determined by HPLC-UV. The results show THSG was rapidly absorbed within 30 min in plasma. Absolute bioavailability of THSG was 40%. Total recovery of unchanged THSG within 24 h were low (0.041% in bile, 0.06% in faeces), whereas the amount of unchanged THSG excreted in the urine within 24 h was lower than LLOQ.

https://www.research...metry_and_high_

 

This study found that 2,3,5,4'-tetrahydroxystilbene 2-O-beta-D-glucoside (THSG), the major bioactive compound from Polygonum multiflorum Thunb., can efficiently inhibit the formation of AGEs in a dose-dependent manner by trapping reactive MGO under physiological conditions (pH 7.4, 37 degrees C). More than 60% MGO was trapped by THSG within 24 h, which was much more effective than resveratrol and its methylated derivative, pterostilbene, the two major bioactive dietary stilbenes.

http://www.ncbi.nlm....pubmed/20104848

 

[Logic]

M1 IS 2,3,5,4'- tetrahydroxystilbene.
I looked diligently for this substance, because of the positive reports of its effects.  Then discovering it is a major metabolite of resveratrol, I just take more resveratrol. 

You sure!??

From the above:
...M1 is probably 3,4,5,4′-tetrahydroxystilbene...

 

I don't see anything saying any different in quite a thorough search?

Link??

[maxwatt]

oops.  close.  Another study might clarify....