Tried NMN but barely felt any difference? Hidden inflammation in your blood vessels speeds up aging! A Science Advances study shows problems with your blood vessel lining drive aging. Low NAD+ isn’t just about topping it up — you also need to stop the damage happening inside your vessels.
As an old Chinese saying goes: Scooping boiling water and pouring it back won’t cool the pot. The only real fix is putting out the fire under it.
This old tale perfectly describes what many people do when taking NAD+ boosters. As we age, our NAD+ levels drop, and we notice less energy and weaker memory. So we take NMN supplements to slow aging, constantly adding raw materials to the “pot.” Yet the results feel underwhelming.
Maybe the real issue isn’t a shortage of raw materials. The fire under the pot is still burning! A research team from the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, published a study in Science Advances. They found a new driver of aging: when we get older, NAD+ gets depleted not only because less is made, but because the production process itself breaks down. And this whole chain of damage starts with the thin lining of your blood vessels — the vascular endothelium.
Your blood vessel lining triggers aging across the whole body
Let’s talk about this endothelium. It’s a delicate layer of cells covering every blood vessel throughout your body. Think of it as your body’s universal supply crew: it delivers oxygen and nutrients, clears waste, maintains the blood-brain barrier, and releases signal molecules to control inflammation and clotting.
Researchers compared tissue samples from young and old mice and humans, from skeletal muscle and brain cortex. Older samples had far fewer endothelial cells. At the same time, two proteins called C/EBPβ and AEP were much more active in these vessel lining cells.
What do these two proteins do? C/EBPβ ramps up inflammation. AEP is a protein-cutting enzyme. Earlier work found C/EBPβ in brain cells rises with age, which then activates AEP. Once the C/EBPβ/AEP pathway stays switched on, brain cells degenerate and lifespans shorten.
This pathway doesn’t only live in the brain. It also acts inside blood vessels. Researchers suspected this active pathway shrinks tiny blood vessels and pushes organs to age faster.
To prove cause and effect, they engineered young mice to make extra AEP just in their vessel lining. These young mice quickly developed classic aging signs: stiff blood vessels, leaky blood-brain barrier, worse endurance, poorer memory, and much shorter lifespans. Male mice’s average lifespan dropped from 706 days down to 435 days, almost a 40% cut.
When your blood vessel lining breaks down, every organ suffers. Muscles and your brain take the first hit. Old, damaged endothelial cells also pump out inflammatory messengers that travel through your bloodstream, broadcasting aging signals all over your body.
And all this triggered by AEP eventually messes up how your body makes NAD+.
The real story behind falling NAD+ levels: it’s not just low supply, active destruction
Most NAD+ in your body comes from this simple production chain: Nicotinamide (NAM) → NMN → NAD+. The first step depends on an enzyme called NAMPT. It’s the gatekeeper that decides how fast NAD+ can be produced. As aging cuts NAD+ levels, energy production, DNA repair and antioxidant defense all weaken. That’s why so many people take NMN or NR to add precursor materials.
But there’s more to this picture. You can’t keep making NAD+ if your “factory equipment” gets broken.
AEP recognizes a specific spot on the NAMPT enzyme and slices it apart. Once cut, NAMPT stops working. The whole NAD+ assembly line slows right down.
Lab tests confirmed this. AEP can directly cut NAMPT in test tubes. In live cells, more AEP means more broken NAMPT and lower NAD+. If researchers alter NAMPT so AEP cannot find its cutting point, NAD+ production stays stable.
Now we understand the full cycle: Aging turns up C/EBPβ inside blood vessel lining cells, which boosts AEP. Active AEP cuts NAMPT, so endothelial cells make far less NAD+. Low NAD+ makes vessel lining cells old and dysfunctional. They release more inflammation. This becomes a vicious loop: worse aging creates more inflammation, and more inflammation speeds aging.
We often think stiff arteries and plaque are just side effects of getting old. This research flips that idea. Damage to your blood vessel lining may actually cause aging across your organs.
From “pouring more boiling water” to “putting out the fire”: move beyond supplements to fix your body’s own system
If AEP damages NAMPT and drives vessel aging and NAD+ loss, blocking AEP could turn things around.
1. Gene knockout: dramatic age reversal in lab mice
Scientists worked with mice engineered to have high C/EBPβ in their vessel lining, which made them age fast. When they knocked out the AEP gene in these mice, NAD+ levels jumped. Blood vessel function and blood-brain barrier integrity recovered. The mice had better exercise stamina, sharper memory and fewer frailty symptoms.
Their lifespans rebounded sharply. Male fast-aging mice went from an average 381 days up to 666 days. Females rose from 435 days to 643 days, nearly matching the lifespan of normal healthy mice.
Most of the rapid aging damage caused by high C/EBPβ happens through AEP. Even with high C/EBPβ, little aging damage occurs without active AEP.
2. Are there AEP inhibitors available?
Beyond gene editing, the team tested a custom high-selectivity AEP inhibitor in mice and compared it directly with NMN. Both treatments raised NAD+ levels in muscle and brain tissue. The inhibitor worked even better.
It also improved blood vessel relaxation, sealed the leaky blood-brain barrier and calmed inflammation more effectively. The mice had better physical performance and cognition, and slightly longer lifespans than the NMN group. Long-term treatment showed no obvious liver or kidney issues in these animal tests.
Important note: these results are only from animal studies. We still need human clinical trials to confirm safe dosages and effects on people. Still, this research sends a clear message: only adding raw materials may not work if the root damage stays unchecked.
Should you keep taking your supplements? How to protect your blood vessels
Reading this, you might wonder what to do with your NMN bottles. Let’s break this down.
NMN and other precursors do supply building blocks for NAD+. But worn-out, inflamed blood vessels and damaged cell environments limit how well they work. That’s why many people take NMN yet feel almost no benefits.
The C/EBPβ/AEP pathway harms your body in multiple ways besides cutting NAMPT:
- Aged vessel lining cells absorb NMN poorly
- Inflammation and DNA damage burn through NAD+ faster
- Fewer tiny blood vessels mean circulating NMN struggles to reach your muscles and brain
Protecting your blood vessel lining is essential. Bad habits including high sugar and high-fat diets, smoking, staying up late and sitting for too long all injure your vessel walls. This speeds up NAMPT breakdown and drains your NAD+.
At Xi’an Springjia, we always remind our partners and customers: fancy supplements are no shortcut. Consistent light cardio, balanced nutrition and keeping blood sugar and lipids under control protect your endothelium and preserve your natural NAD+ production.
Don’t just chase “replace what you lose.” Try to understand why those nutrients get depleted in the first place. Chasing trendy supplements can end up being like scooping boiling water to cool a pot. Looking after your blood vessels and protecting your body’s natural repair systems is the sustainable, long-term anti-aging strategy, and that’s the philosophy we stand for at Xi’an Springjia.