Each person’s body’s response to NMN may vary from individual to individual.
Factors such as age, sex, underlying health status, and genes may affect the effect of NMN.
Absorption process
When NMN (niacinamide mononucleotide) enters the body orally, a small part of it may be absorbed by the oral mucosa at first, but this part is relatively small.
Subsequently, most of the NMN enters the gastrointestinal tract. In the gastrointestinal tract, the absorption of NMN complicated.
It can absorbed by special transporters that act like “little guards” that recognize and help NMN pass through intestinal wall cells into the bloodstream.
For example, it has found that specific transporters in small intestinal epithelial cells play a key role in the absorption of NMN, which is similar to the absorption of other nutrients, but has its own unique mechanism.
Once NMN absorbed into the bloodstream, its transported to various parts of the body along with the blood flow.
Just like express packages sent to various places through a logistics network, NMN can quickly reach various tissues and organs such as liver, muscle, and brain in the “transportation network” of blood.
During this process, various components in the blood will interact with NMN, and the concentration of NMN will gradually decrease during transport as its distributed to different tissues, but this also ensures that all parts of the body have the opportunity to obtain NMN to play its role.
Cell uptake and transformation
Once NMN reaches the target tissue, it needs to enter cells to be effective. Cells have their own set of “access mechanisms” to take up NMN.
There are some specific transporters or channels on the cell membrane that recognize and allow NMN to enter the cell interior.
The presence of these transporters and channels ensures that NMN can enter the cell precisely, as if each cell has its own “access control system” that only allows certain “visitors” (NMN) to enter.
After entering the cell, NMN undergoes a critical transformation process.
NMN is the precursor of NAD +. In the cell, NMN quickly converted into NAD + through a series of chemical reactions under the catalysis of enzymes such as nicotinamide riboside kinase.
This transformation process is like a “magic transformation” in which NMN becomes NAD +, which is essential for energy metabolism and numerous physiological functions within cells.
NAD + is like an “energy transfer station” and “signal regulator” in the cell, participating in many important physiological processes such as cell respiration, DNA repair, and gene expression regulation.
Physiological function play
The transformed NAD + plays a central role in cellular energy metabolism.
Its involved in many aspects of cellular respiration, such as glycolysis, tricarboxylic acid cycle and oxidative phosphorylation.
During glycolysis, NAD + acts as a coenzyme to help break down glucose into pyruvate, while producing a small amount of ATP (adenosine triphosphate).
During the subsequent tricarboxylic acid cycle and oxidative phosphorylation, NAD + accepts electrons and passes them to oxygen, which produces large amounts of ATP to provide energy to the cell.
This is like NAD + in the “energy factory” (mitochondria) in the cell, promoting the operation of various “machines” (metabolic enzymes), and continuously producing energy “currency” (ATP).
NAD + is also involved in the DNA repair process.
When a cell DNA is damaged, for example by ultraviolet light, chemicals, or free radicals produced by the cell own metabolism, NAD + involved in activating PARP (polyADP-ribose polymerase).
PARP is an important DNA repair enzyme that uses NAD + as a substrate to repair damaged DNA and ensure that the genetic information of cells is stable.
At the same time, NAD + regulates gene expression by interacting with proteins such as SIRT1 (silencing information regulator 1).
SIRT1 is a NAD + dependent deacetylase, which can regulate the expression of many genes related to aging, metabolism, etc., thus affecting the function and fate of cells.
