Excerpt from the interview:
"Let’s talk a little bit more about your work. You are very well known for your work with NAD+ and its precursors; we’re often asked whether NR or NMN is better. However, the data seems to suggest that different precursors are more or less efficient in a tissue- or organ-dependent manner. Would it be fair to say that rather than asking which is better, we should instead consider these differences and that both may have their place?
They’re very similar molecules, and both have been shown to provide a variety of health benefits in mice. That doesn’t mean either of them will work to slow aging in humans, and that’s why placebo-controlled clinical trials are required to know if one of them, or both of them, will work in certain conditions.
There has been a great deal of debate over the ability of NMN to pass through the plasma membrane to reach the interior of the cell. However, you and your team recently showed that under certain conditions, NMN can indeed enter the cell via a previously undocumented transporter without the need to change back to NR. Have there been any further developments with this? In particular, what does this mean for the efficiency of NMN, given its close proximity to NAD+ in the salvage pathway?
The NMN transporter was recently published by Shin Imai’s group; I wrote a commentary about it. I’m aware of work that’s not yet published by a few different labs, looking at how these molecules travel through the body of a mouse. The conclusion is that some tissues have transporters, some don’t. It can even vary depending on where in the gut you’re talking about. I think, in the end, what’s going to happen, like most areas of science, is that everybody’s right; it just depends on what you’re talking about."
https://www.leafscience.org/an-intervie ... -sinclair/