192 replies to this topic

[Turnbuckle]

 

The big question in my mind is why some people measure NAD+ levels over 300% higher than others following oral ingestion of NR.  As illustrated in the chart of the 8 participants in this same study:

 

 

 

 

There was an age range of 21–50, and it's known that NAD+ baseline drops off with age, likely due to growing levels of defective mitochondria. While the paper does not identify subject age with the individual curves, the ability of defective mitochondria to utilize the supplement will also likely be compromised. 

[LawrenceW]

Or, why kidney likes NMN more than NR.

[MikeDC]

The big question in my mind is why some people measure NAD+ levels over 300% higher than others following oral ingestion of NR. As illustrated in the chart of the 8 participants in this same study:

There was an age range of 21–50, and it's known that NAD+ baseline drops off with age, likely due to growing levels of defective mitochondria. While the paper does not identify subject age with the individual curves, the ability of defective mitochondria to utilize the supplement will also likely be compromised.

We thought NAD+ can’t be increased much higher in young people. The study shows NAD+ increase in younger people can be much higher than for old people. Old people have lower NAD+ and have less increase of NAD+ from NR supplementation. The best time to start NR is probably when you are at 20.

Edited by MikeDC, 04 April 2018 - 11:13 PM.

[MikeDC]

Or, why kidney likes NMN more than NR.

Kidney definitely likes to accumulate NMN. Most NMN in blood circulation is sucked up by kidney tissues. This is just my theory based on the ling LIU dissertation.

[able]

We need an NMN study that follows NAD+ for more than 6 hours. We also need to know why NMN likes kidney so much.

 

Yes, and we need an NR study that is longer than a couple of months (vs 12 months for NMN). 

 

And why NR likes liver so much.

 

Jeez. must you really destroy every discussion with your incessant blather?

 

Howard makes a great point we should discuss, but you can't resist messing it up.

[Turnbuckle]

 

 

The big question in my mind is why some people measure NAD+ levels over 300% higher than others following oral ingestion of NR. As illustrated in the chart of the 8 participants in this same study:
 

There was an age range of 21–50, and it's known that NAD+ baseline drops off with age, likely due to growing levels of defective mitochondria. While the paper does not identify subject age with the individual curves, the ability of defective mitochondria to utilize the supplement will also likely be compromised.

We thought NAD+ can’t be increased much higher in young people. The study shows NAD+ increase in younger people can be much higher than for old people. Old people have lower NAD+ and have less increase of NAD+ from NR supplementation. The best time to start NR is probably when you are at 20.

 

 

 

I agree that it likely varies by age, but it's unfortunate as the people who really need it will not benefit from it.

[MikeDC]

The big question in my mind is why some people measure NAD+ levels over 300% higher than others following oral ingestion of NR. As illustrated in the chart of the 8 participants in this same study:

There was an age range of 21–50, and it's known that NAD+ baseline drops off with age, likely due to growing levels of defective mitochondria. While the paper does not identify subject age with the individual curves, the ability of defective mitochondria to utilize the supplement will also likely be compromised.

We thought NAD+ can’t be increased much higher in young people. The study shows NAD+ increase in younger people can be much higher than for old people. Old people have lower NAD+ and have less increase of NAD+ from NR supplementation. The best time to start NR is probably when you are at 20.

I agree that it likely varies by age, but it's unfortunate as the people who really need it will not benefit from it.

It is inaccurate to say old people will not benefit from it. They benefit a lot from it.

[Michael]

Just looked at her Chemistry Department  dissertation and it's not totally clear what portion of the blood she tested.  "Whole blood" is mentioned once but there is no mention anywhere of centrifuging it to separate the cells from the plasma.  The problem generally cited isn't so much the sensitivity of the test but that NR in drawn blood degrades so quickly that even if it is there, it might be gone by the time its done centrifuging to separate out the plasma. There is mention of immediately flash-freezing the blood to avoid this degradation but the plasma cannot be separated in that state. 
 
Howard

 
I say again: "It's also not clear to me why we would care particularly much about levels of NR,  NMN, eNAMPT and the rest except as they may inform about tissue NAD+, — but we don't have to guess about this, since as documented from multiple studies and in multiple tissues across multiple timescales, NR pretty consistently outperforms NMN [in raising tissue NAD+]. (As noted, a possible exception is the  hypothalamus [SNIP]"
 

We need an NMN study that follows NAD+ for more than 6 hours. We also need to know why NMN likes kidney so much.

 

Or, why kidney likes NMN more than NR.

 
What we need to pay attention . Ron H put forward a pretty plausible explanation, which I subsequently quoted approvingly:
 

Second, there is the matter of CD73.

A general line of reasoning, at least by people posting in this forum, is that NR is better than NMN at boosting NAD+ synthesis, simply because NMN needs to be converted by CD73 to NR before it can enter the cell, whereas NR itself enters the cell directly. In fact, this seems to be corroborated by most head-to-head comparisons of NR and NMN in Ratajczak paper [PMID 27725675]. Such comparisons are shown in Figs 2d and e, 4, 5e, 6a (controls), 7 and 8a. [...]

• I find it striking that in Figure 7 of the Ratajczak paper only in kidney the effects of NR and NMN are indistinguishable, and that CD73 levels in this organ are clearly higher than in the other tissues (cf. their supplementary Fig. 3a). In Figure 8 10-fold lower doses of NR and NMN are used and here the advantage of NR over NMN disappears.

 
able wrote: And [we need to know] why NR likes liver so much.

I think that's pretty obvious.

 
able wrote: Yes, and we need an NR study that is longer than a couple of months (vs 12 months for NMN).

Again, Able: we have several NR studies that lasted 3-4 mo, and one that lasted 10.
 

We thought NAD+ can’t be increased much higher in young people. The study shows NAD+ increase in younger people can be much higher than for old people. Old people have lower NAD+ and have less increase of NAD+ from NR supplementation. The best time to start NR is probably when you are at 20.

 
I put it to you that this actually is a strong argument against young people using the stuff. IF there is a benefit to boosting NAD+ levels, it's presumably to restore youthful levels of NAD+ in older people whose NAD+ levels may hypothetically be repressed by aging processes, leading to downstream metabolic dysfunction. Raising it over the levels in a young healthy person is more likely to lead to redox imbalance, or metabolic dysfunction resulting from homeostatic feedback (futile cycling, etc), which latter has been observed both in human studies (the Elysium trial) and in animals (the Sinclair exercise study).
 
Important questions will include whether such feedback occurs only to people achieving "excessively" high NAD+ levels, or whether everyone tends to trend back to his or her baseline level over time. As blue has reminded us a couple of times, the UWash study only lasted 9 days, and the Colorado trial only 6 weeks, and the Elysium and Colorado trials only reported medians and ranges for the NAD+ metabolome: the feedback effect was not observed in the Elysium trial at 30 days, but was at 60.
 

It is inaccurate to say old people will not benefit from it. They benefit a lot from it.

We have no idea if they benefit from it or not. Anecdotes are not evidence, and there's only hints of benefits inconsistently reported in the short-term studies to date.

[MikeDC]

“We have no idea if they benefit from it or not. Anecdotes are not evidence, and there's only hints of benefits inconsistently reported in the short-term studies to date.”
When a majority of people taking NR showed various benefits including blood work, it is no longer anecdote. It is a large scale clinical trial. The Colorado trial shows benefits in normalizing blood pressure. Future clinical trials will confirm all the anecdotes that have been reported.

[Michael]

“We have no idea if they benefit from it or not. Anecdotes are not evidence, and there's only hints of benefits inconsistently reported in the short-term studies to date.”
When a majority of people taking NR showed various benefits including blood work, it is no longer anecdote. It is a large scale clinical trial. The Colorado trial shows benefits in normalizing blood pressure. Future clinical trials will confirm all the anecdotes that have been reported.

 

Ahem. There were twenty-four people in this trial: "large-scale" would be at least fifty times that number. No benefits were observed on any parameter of blood work in this trial. There may have been a benefit in normalizing blood pressure in the subgroup of subjects with baseline hypertension: the authors themselves aren't claiming this, and are careful to say that "Because this post-hoc subgroup analysis was exploratory, no statistical inferences can be made. ... [We] identify SBP and aortic stiffness as promising cardiovascular outcomes to be assessed in larger-scale clinical trials." Similarly, they don't make this exploratory finding the focus of the abstract, focusing instead on safety and NAD+; they only say that "Our results also provide initial insight into the effects of chronic NR supplementation on physiological function in humans, and suggest that, in particular, future clinical trials should further assess the potential benefits of NR for reducing blood pressure and arterial stiffness in this group." And if you look at Supplementary Table 6, you can see that even in the subgroup analysis, plenty of subjects in the NR phase had BP at least as high as people the placebo phase.
 

[able]

 

 

 
 

 
able wrote: Yes, and we need an NR study that is longer than a couple of months (vs 12 months for NMN).

Again, Able: we have several NR studies that lasted 3-4 mo, and one that lasted 10.
 

 

 

Good point, I was sloppy and should say 3-4 months.

 

On the 10 months, I disagree on how that is characterized.

 

In the study you speak of they tracked some parameters over a few months (2 or 3?).

 

Then, they recorded the mortality rates  up to  10 months.

 

It showed a nice increase in lifespan, which is good.

 

But they did not report ANY parameters past that 2-3 months.  So we have NO IDEA what happened to NAD+ levels, or anything else.

 

Compared to  the 12 month study by Mills which tracks everything for the entire 12 months.  

 

Not that I expect much difference in long term effects of NR vs NMN, but I just think there is not the same data for NR past 3 months.

Edited by able, 06 April 2018 - 10:51 PM.

[Michael]

I disagree on how that is characterized.

 

In the study you speak of they tracked some parameters over a few months (2 or 3?).

 

Then, they recorded the lifespan over 10 months.

 

It showed a nice increase in lifespan, which is good.

 

But they did not report ANY parameters past that 2-3 months.  So we have NO IDEA what happened to NAD+ levels, or anything else.

 

I agree, of course: different studies track different things over different time periods in different models. What you said was, "we need an NR study that is longer than a couple of months (vs 12 months for NMN)" — and, previously, "There is NO study of NR for 12 months.  I believe the longest is 3 months?" — and prior to that, "[Michael,] you mentioned long term studies on NR - is there some 12 months or longer like the NMN study?" Again: we have such studies. If what you mean is "we need an NR study that tracks tissue NAD+ levels longer than a couple of months (vs 12 months for NMN)," then just say so.

[able]

Yes, I wasn't as accurate as you - then again, no-one is here    

 

I'll try and do better.

[MikeDC]

Ahem. There were twenty-four people in this trial: "large-scale" would be at least fifty times that number. No benefits were observed on any parameter of blood work in this trial. There may have been a benefit in normalizing blood pressure in the subgroup of subjects with baseline hypertension: the authors themselves aren't claiming this, and are careful to say that "Because this post-hoc subgroup analysis was exploratory, no statistical inferences can be made. ... [We] identify SBP and aortic stiffness as promising cardiovascular outcomes to be assessed in larger-scale clinical trials." Similarly, they don't make this exploratory finding the focus of the abstract, focusing instead on safety and NAD+; they only say that "Our results also provide initial insight into the effects of chronic NR supplementation on physiological function in humans, and suggest that, in particular, future clinical trials should further assess the potential benefits of NR for reducing blood pressure and arterial stiffness in this group." And if you look at Supplementary Table 6, you can see that even in the subgroup analysis, plenty of subjects in the NR phase had BP at least as high as people the placebo phase.

When I said large scale trial, I meant all the people that have been taking NR and reported great benefits.

NR is not a drug in the sense that a drug like statin will lower cholesterol level even when your cholesterol level is normal. NR will only help to normalize blood levels outside range. The participants in the Colorado trial have an average cholesterol of 167. This is lower normal and NR will not make it even lower.

[hav]

I was thinking about non-muscle effects of NR and NMN, noting their detection along with NAD+ in other places like kidney, liver, and apparently circulating blood cells.  One reported health effect is on glucose metabolism.  Sinclair showed this with ip-injection of NMN in female mice induced into obesity with a high fat diet, finding glucose reduction due to NMN effect on the liver.

 

NAD⁺ levels were measured in both muscle and liver. Previously it was shown that 7 days of NMN injection increased NAD⁺ levels in livers of diabetic mice (Yoshino et al., 2011), and exercise increased NAD⁺ in rodent skeletal muscle (Cantó et al., 2010; Koltai et al., 2010). In our experiment there was a trend for a reduction in NAD⁺ by HFD [high fat diet] but a significant increase by NMN injection in both tissues, with the greatest increase in liver (Figures 4A,B). Exercise also increased NAD⁺ levels in muscle but not in liver compared to the HFD sedentary group

 

A similar blood glucose effect was also shown in the  Trammell NR study using mice fed similar high fat diets plus two low doses of streptozotocin to induce diabetes symptoms, and countering with relatively small NR oral dosages (75 mg/kg). 

 

NR greatly reduced non-fasting and fasting blood glucose

...

Here we show that NR improves fasting glucose levels and glucose tolerance of PD [pre diabetic] mice, while providing resistance to a substantial degree of hepatic steatosis, hypercholesterolemia, liver damage and weight gain.

 

This study also observed an a1c improvement, suggesting a direct NR effect on red blood cells.

 

NR tended to normalize hemoglobin A1c (HbA1c) and significantly improved nonfasting glucose (P < 0.001) in T2D [type 2 diabetic] mice

 

Which connects back to Airhart and probably Ling Liu detecting NR in whole blood but not blood plasma suggesting it was in the cellular portion.  Sinclair didn't look for an a1c effect from NMN treatment but I expect he might next time.

 

Howard

 

Edited by hav, 08 April 2018 - 05:07 AM.

[MikeDC]

I know many people whose A1C dropped after taking NR.

[Michael]

[Cited and other studies find that NR & NMN improve glycemia in various models of diabetes]. This study also observed an a1c improvement, suggesting a direct NR effect on red blood cells.

Why would you say so? As you note, these studies consistently show reductions in postprandial glucose amongst diabetic animals, and sometimes show effects on fasting glucose too; an effect on either parameter will automatically lower a1c. Why posit a direct effect on RBC?

 

I hear the buzz of Occam's razor approaching ...

Edited by Michael, 08 April 2018 - 02:12 PM.

[MikeDC]

https://www.ncbi.nlm...08/#!po=44.2029

I can’t believe we missed this information in this old paper.
Why NMN disappear fast in blood after IV injection? It is metabolized by CD38.

“We now report, for the first time, that CD38 is one of the main enzymes degrading NMN in mouse tissues (Figure 6B), implying that CD38 has a key role in the pharmacokinetics of NMN. This was confirmed by the rapid disappearance of NMN in blood of WT, but not CD38KO mice”

[Michael]

https://www.ncbi.nlm...08/#!po=44.2029

I can’t believe we missed this information in this old paper.

 

We didn't: we started discussing it when it first came out, as well as its followup study, and have discussed or alluded to it repeatedly ever since, including everything from casual asides to an entire thread. (In fact, there's a ton of evidence that CD38 is not the sole or even the main driver of age-associated NAD+ decline — but that's a megapost for another day and another thread).

 

It's not just NAD+ and NMN, BTW.

 

 

NR is resistant to CD38 enzymatic activity in vitro (Figure 6A). However, since NR is converted to NMN (Bieganowski and Brenner, 2004; Grozio et al., 2013), it is still possible that CD38 may have a role in NR-mediated pharmacokinetics. To test this hypothesis, we administered NR to WT and CD38KO mice and followed plasma levels of NR, NMN, and NAD⁺. We show that, following an i.p. injection of NR (500 mg/kg), the levels of NR, NMN, and NAD⁺ in the blood of CD38KO mice are more stable than in WT animals (Figure 6D). In fact, levels of NR rapidly decline in WT mice, with a decrease of about 25% in the first 75 minutes, while NR levels are maintained in CD38KO mice. 150 minutes after NR injection, there were still higher levels of NMN and NAD⁺ in plasma of CD38KO than in WT mice (Figure 6D). These results indicate that CD38 is involved in the metabolism of NAD precursors in vivo.

 

 

Edited by Michael, 08 April 2018 - 10:01 PM.

[MikeDC]

CD38 has to be the main driver of NAD+ consumption. The CD38 KO mice’s NAD+ didn’t decline with age or much smaller than wild mice.

[hav]

Why would you say so? As you note, these studies consistently show reductions in postprandial glucose amongst diabetic animals, and sometimes show effects on fasting glucose too; an effect on either parameter will automatically lower a1c. Why posit a direct effect on RBC?

 

I hear the buzz of Occam's razor approaching ...

 

For the reasons stated... observed presence of NR in whole blood but not plasma, suggesting it is in the cellular portion. We just don't know if it's in all the blood cells or some of them. Since the observed effect is to the hemoglobin A1c protein found in red blood cells, NR in those cells might be contributing to that effect. 

 

Howard

Edited by hav, 09 April 2018 - 04:27 AM.

[Michael]

For the reasons stated... observed presence of NR in whole blood but not plasma, suggesting it is in the cellular portion. We just don't know if it's in all the blood cells or some of them. Since the observed effect is to the hemoglobin A1c protein found in red blood cells, NR in those cells might be contributing to that effect. 

 

Howard

 

But that's a totally unnecessary hypothesis — "multiplicanda entia sine necessitate," yes? Again: these studies consistently show reductions in postprandial glucose amongst diabetic animals, and sometimes show effects on fasting glucose too; an effect on either parameter will automatically lower a1c. That's not an hypothesis: that's a known fact of biochemistry. So there's no need to posit any additional, purely hypothetical mechanism mediated by NR's association wiht RBC.

[hav]

But that's a totally unnecessary hypothesis — "multiplicanda entia sine necessitate," yes? Again: these studies consistently show reductions in postprandial glucose amongst diabetic animals, and sometimes show effects on fasting glucose too; an effect on either parameter will automatically lower a1c. That's not an hypothesis: that's a known fact of biochemistry. So there's no need to posit any additional, purely hypothetical mechanism mediated by NR's association wiht RBC.

 

Ha, ha, at least your critique has evolved from "too complicated" to "unnecessary" which seems to be some progress.  I feared "overly simplistic" myself, considering how little I understand about the inner workings of diabetes, glucose metabolism,  and a1c.  So I kind of tried to stay away from that and focus on, "Where's the NR hiding in the blood?" And, "What's it doing there?"  Perhaps unnecessary but inquiring minds want to know.  Don't want to get too far afield in a thread about NAD+ but...  this glucose/a1c study in fact cites a divergence of glucose and a1c responses attributable to differences in erythrocyte lifespan, observing that "HbA1c levels can be generated by different glucose profiles"... again with the bloody red erythrocyte cells. But I think it's at least consistent with the notion that NR may be entering red blood cells and extending their lifespan.

 

Sorry if I'm wandering off-topic and thanks for your indulgence.
 

Howard

Edited by hav, 09 April 2018 - 04:38 PM.

[docmaas]

I never said NMN is superior. I said NMN is a very lousy NAD+ precursor. 6400% less effective than NR.

It would be great if someone can post that 10 month long NR study article. It is protected.

We have plenty of human experiences that NR is great to improve lipid and glucose control. We will see these data from clinical trials eventually.

 

https://www.research...n_mice/download

[docmaas]

You guys appear to be misinterpreting Fig. 2.7e in the Thesis. You're reading it as if it shows the level of NAD+, or NAD+ boost, resulting from administration of IV and oral NR and NMN — which is not what it shows. What it shows is what percentage of the NAD+ in the tissue at time of measure is derived from pre-existing or late-salvage NAD+ (M+0), or directly from parent supplement (M+2), or from NAM derived from early metabolism of supplement (M+1). None of that tells you the actual level of NAD+ in the tissue is at that time— just the fractional breakdown of what's there. I haven't read the paper, but I don't see anywhere where actual levels of NAD+ following supplementation are given.

 

I'm seeing they used the same weight of each of the compounds 50mg/kg rather than using mol weighting.  NMN is 2.6 times the weight of NRaning that  the effective availability of the molecules from each compound differs by that same factor.  There are 2.6 times as many NR molecules available as NMN.  

 

I'm just reading this thread tonight so this might have gotten pointed out later in the thread but just in case here it is.

Edited by docmaas, 03 October 2018 - 02:16 AM.

[MikeDC]

I'm seeing they used the same weight of each of the compounds 50mg/kg rather than using mol weighting.  NMN is 2.6 times the weight of NRaning that  the effective availability of the molecules from each compound differs by that same factor.  There are 2.6 times as many NR molecules available as NMN.  

 

I'm just reading this thread tonight so this might have gotten pointed out later in the thread but just in case here it is.

 

It is more like 1.3 times. 335/255.  Since NR and NMN are sold by weight, we will have to compare them based on weight.

[docmaas]

It is more like 1.3 times. 335/255.  Since NR and NMN are sold by weight, we will have to compare them based on weight.

 

You are right.  Thanks for the correction.  However, it is not we that decide how to dose and compare but those who do the experiment.  

 

Mike

[stefan_001]

Reviving this thread about the Ling Liu dissertation "Quantitative Analysis of NAD Synthesis-Breakdown Fluxes" that was re-debated in the "NR Personal experiences thread".

[Harkijn]

Reviving this thread about the Ling Liu dissertation "Quantitative Analysis of NAD Synthesis-Breakdown Fluxes" that was re-debated in the "NR Personal experiences thread".

I think that's a good idea, for in one of the NAD threads  someone even called NAD 'just a compound' . Anyway this complicated subject needs continuous study even by experts.

 

I post a link to (the abstract of) a 2019 review of  the present state of research on NAD metabolism/ precursors. 

In the full text the authors also pay attention to NADases like SARM1 and CD38. CD38 was discussed earlier in the present thread but also in several others.

https://www.ncbi.nlm...pubmed/30626706

Edited by Harkijn, 11 January 2019 - 12:26 PM.

[Fredrik]

I think that's a good idea, for in one of the NAD threads  someone even called NAD 'just a compound' 

 

First, thank you for the link to a new review on NAD metabolism. Second, If you are going to quote me do it correctly, please. I never said it was "just a compound" and I am not denying the importance of NAD as a cellular compound.

 

I said:

 

What good is increasing NAD levels in certain blood cells if there is no significant clinical benefit to show? NAD is a cofactor in the body, a compound, not a health benefit in and of itself.

 

 

I fully realize the importance of NAD. I am just reminding everyone that we have mechanistic explanations and positive animal data. What we still do not have is the same positive human results. In fact, we have some worrisome non-results that differ from the animal trials.

 

High dose nicotinamide riboside (2000 mg) showed NO beneficial effects in humans on any of these health-related parameters:

 

• no effect on insulin sensitivity
• endogenous glucose production
• glucose disposal
• glucose oxidation
• resting energy expenditure
• lipolysis
• cholesterol
• fat oxidation
• body composition

 

"Results: Insulin sensitivity, endogenous glucose production, and glucose disposal and oxidation were not improved by NR supplementation. Similarly, NR supplementation had no effect on resting energy expenditure, lipolysis, oxidation of lipids, or body composition."

 

 

 

 

1. Dollerup OL, Christensen B, Svart M, Schmidt MS, Sulek K, Ringgaard S, Stødkilde-Jørgensen H, Møller N, Brenner C, Treebak JT, Jessen N. A randomized placebo-controlled clinical trial of nicotinamide riboside in obese men: safety, insulin-sensitivity, and lipid-mobilizing effects. The American journal of clinical nutrition. 2018 Jul 10;108(2):343-53.

Edited by Fredrik, 11 January 2019 - 02:55 PM.