Comment · Sun, February 20, 2022 · ND Owner
Slc12a8 possibly not an NMN transporter?
Original post in this thread
__shamir__ · 3 points
I came across an article, ["Absence of evidence that Slc12a8 encodes
a nicotinamide mononucleotide transporter"](https://sci-hub.hkvisa.net/10.1038/s42255-019-0085-0#), which appears to debunk [at least some of] the evidence presented in Slc12a8 is a nicotinamide mononucleotide transporter for Slc12a8's action as an NMN transporter. The article is quite brief so I won't quote from it, but it basically disputes the validity of the techniques used (especially from a chemistry / biochemistry perspective from what I can gather)
OTOH, some of the findings in Slc12a8 is a nicotinamide mononucleotide transporter seem pretty definitive. But if the argument of the critique, namely that the analytical methods were invalid/flawed holds, then I suppose it can't necessarily be trusted. Here's some quotes from a relevant subsection, "Biochemical features of the Slc12a8 protein":
> Next, we overexpressed the full-length mouse Slc12a8 cDNA in mouse NIH3T3 cells. We chose this cell line because it does not have any detectable extracellular activities of CD73 (converting NM…
What they were answering
Direct reply to the original post — see the thread post above.
u/MisterYouAreSoDumb · ND Owner
Competing interests
C.B. owns stock in and is chief scientific adviser to ChromaDex, Inc.
These studies are all sponsored by Chromadex, who has a history of trying to convince people that NMN is useless, and that people need nicotinamide riboside instead. Hmmm, I wonder why they might do that... Because they own a patent on NR! It's blatant conflicts of interest. Plus, the authors of the paper already responded to their bullshit.
Reply to: Absence of evidence that Slc12a8 encodes a nicotinamide mononucleotide transporter
Myself, my product specialist, and my lab director read through both of those papers when they were released. The data put forth by Grozio et al. is more compelling, and ~~they don't have conflicts of interest~~. Their data is good. The methods were not flawed, and their validation data is solid. Chromadex is once again trying to muddy the waters to try and get people to use nicotinamide riboside instead of NMN.