Niagen alleviates Parkinson’s disease symptoms but downregulates dopamine metabolism?

[Bolt_Upright]

I understand that the B3 study used Niacin, but I was researching NR and found this report from March showing eventually NR lowers dopamine (based on worms and mice). Now I'm wondering if this might apply to Niacin also? (I still take 250 mg of Niacin at night and 50 mg more in the afternoon.

"We find that NR attenuates PD associated disease symptoms both in C. elegans and in mice, but the primary endpoint - a rescue of nigrostriatal dopamine levels and function - is not reached. Instead, NR disturbs DA metabolism upon drug-induced proteostasis failure in mice."

biorxiv.org/content/biorxiv...

Nicotinamide riboside alleviates Parkinson’s disease symptoms but downregulates dopamine metabolism upon lactacystin-induced proteostasis failure

Giorgio Turconi1, Farhan Alam2, Tanima SenGupta3, Sini Pirnes-Karhu2, Soophie Olfat1, Mark S. Schmidt4, Kärt Mätlik1, Ana Montaño-Rodriguez1, Vladimir Heiskanen2, Petteri T. Piepponen5, Charles Brenner6, Carina I. Holmberg7, Hilde Nilsen3, Jaan-Olle Andressoo1,8§, Eija Pirinen2

I don't know if this confirms a danger of using NR, or if it bodes poorly for Niacin. Definitely going to research it more.

Update 9/3/2021: I contacted the authors of the report from March showing eventually NR lowers dopamine (based on worms and mice). I will just share what they wrote. I did not really ask them a question, just let them know I found their results concerning. They were very nice and replied and it looks to me like they really don't have any evidence that taking Niacin downregulates Dopamine production:

"It is indeed at that point quite safe to say that without proteasome inhibition using lactacystin we do not see reduction in dopamine upon NR application. How is the situation in PD remains to be seen. We and for that sake-noone knows how welldoes lactacystin injection model Parkinson’s disease in humans. It maybe that not at all, it may be that it models some patients and it may be that quite many-but it is not possible to know at that point for sure. We found it important to report our results, as science should."

So that was nice of them. Glad I stayed on the Niacin.

[park_bear]

Another good cautionary note. Given the high cost of nicotinamide riboside, it might be a good one to skip. I tried it for a while and it did not do anything for me.

[Bolt_Upright in reply to park_bear]

I contacted the authors of the report from March showing eventually NR lowers dopamine (based on worms and mice). I will just share what they wrote. I did not really ask them a question, just let them know I found their results concerning. They were very nice and replied and it looks to me like they really don't have any evidence that taking Niacin downregulates Dopamine production:

"It is indeed at that point quite safe to say that without proteasome inhibition using lactacystin we do not see reduction in dopamine upon NR application. How is the situation in PD remains to be seen. We and for that sake-noone knows how welldoes lactacystin injection model Parkinson’s disease in humans. It maybe that not at all, it may be that it models some patients and it may be that quite many-but it is not possible to know at that point for sure. We found it important to report our results, as science should."

So that was nice of them. Glad I stayed on the Niacin.

[Bolt_Upright]

I contacted the authors of the report from March showing eventually NR lowers dopamine (based on worms and mice). I will just share what they wrote. I did not really ask them a question, just let them know I found their results concerning. They were very nice and replied and it looks to me like they really don't have any evidence that taking Niacin downregulates Dopamine production:

"It is indeed at that point quite safe to say that without proteasome inhibition using lactacystin we do not see reduction in dopamine upon NR application. How is the situation in PD remains to be seen. We and for that sake-noone knows how welldoes lactacystin injection model Parkinson’s disease in humans. It maybe that not at all, it may be that it models some patients and it may be that quite many-but it is not possible to know at that point for sure. We found it important to report our results, as science should."

So that was nice of them. Glad I stayed on the Niacin.