Nicotinamide Mononucleotide (NMN): Difference between revisions

The primary issue is that NMN's role as a direct precursor is effective only when it is '''inside the cell'''. This raises questions about how NMN, when ingested or administered externally, enters the cell to contribute to NAD+ synthesis. The central controversy surrounding NMN as a precursor to NAD+ lies in its mechanism of cellular entry. While NMN is a direct precursor of NAD+ within the cell, the debate focuses on whether NMN can be directly absorbed by cells or if it must first be converted to '''Nicotinamide Riboside (NR)'''. In that case, NR would hold an edge over NMN because NR would need on conversion less compared to NMN.  

One hypothesis is that NMN can directly enter cells through specific transporters. The ''Slc12a8'' transporter in the aged mouse ileum is an example, suggested to facilitate NMN's direct absorption<ref name="ref160">[Source 160]</ref>. However, this notion has faced challenges due to conflicting research findings<ref name="ref161">[Source 161]</ref><ref name="ref162">[Source 162]</ref>, and the functionality of ''Slc12a8'' in humans is yet to be conclusively determined.