New research suggests that they key antioxidant in green tea might restore aging brain cells when combined with a significant dose of vitamin B3. (Photo by Eric Miguel on Shutterstock)
Lab-dish study using brain cells from elderly mice yields promising results for a potential anti-aging recipe, but more research is necessary.
In A Nutshell
Aging brain cells in mice restored youthful energy balance (GTP levels) within 16 hours using vitamin B3 and green tea extract
The treatment cleared toxic protein buildup and improved survival by 22% in Alzheimer’s-model neurons
It also restored waste-clearing vesicle function by reducing the buildup of Rab7- and Arl8b-tagged vesicles
Findings are based on in vitro studies and will require confirmation in living animals and humans
IRVINE, Calif. — Can brain cells really bounce back in a day? In an exciting lab-dish experiment, brain cells from elderly mice regained their youthful energy balance in just 16 hours using a combination of nicotinamide (vitamin B3) and EGCG, the main antioxidant in green tea.
As brain cells age, they lose their ability to produce adequate levels of GTP, a molecular energy source essential for cleaning up waste. Without it, neurons struggle to remove damaged proteins and debris, which can build up and disrupt brain function.
Published in GeroScience, the research shows that aged brain cells, including those from mice with Alzheimer’s-like symptoms, restored their GTP levels after a single treatment. The combination also cleared toxic protein clumps linked to Alzheimer’s and improved cell survival by 22% in aged Alzheimer’s-model neurons.
How Vitamin B3 and Green Tea Compound Restore Brain Cell Function
Researchers from the University of California, Irvine, discovered that combining nicotinamide with EGCG could rapidly restore lost cellular energy. Nicotinamide boosts levels of NAD+, a molecule that supports cellular metabolism and serves as a precursor in GTP production. EGCG activates Nrf2, a cellular defense switch that turns on protective antioxidant genes.
Within 30 minutes of treatment, Nrf2 began moving into the nucleus of neurons, where it activated known target genes like NQO1. This response suggests the treatment provides both immediate antioxidant protection and a boost in cellular energy balance.
The research team used brain cells from young (2–6 months), middle-aged (8–11 months), and old (17–28 months) mice. Half came from healthy mice, while the other half came from genetically modified mice that develop Alzheimer’s-like symptoms with age.
Using a fluorescent biosensor called GEVAL, scientists measured real-time GTP levels inside the neurons. They then treated the older neurons with nicotinamide, EGCG, or both together for 16 hours.
Though follow-up studies are in order, the findings are great news for older adults, particularly those who drink green tea. (Photo by Krakenimages.com on Shutterstock)
Brain Cells Regain Youthful Energy Levels After Treatment
Energy levels followed different trajectories depending on age and disease. In healthy neurons, GTP levels rose in middle age before falling in old age. In Alzheimer’s-model neurons, the decline happened earlier and remained low.
After 16 hours of combination treatment, neurons from both groups regained GTP levels comparable to those of young cells. This energy restoration had visible effects: neurons resumed clearing cellular waste, including amyloid-beta protein clumps often seen in Alzheimer’s disease.
The treatment also reduced the buildup of vesicles involved in waste processing. These vesicles, marked by the GTPases Rab7 and Arl8b, tend to accumulate in aging neurons when energy is low. After treatment, the number and size of these vesicles returned to youthful levels, suggesting that cellular cleanup pathways were functioning more normally again.
Foods rice in vitamin B3 (Niacin). (© Danijela – stock.adobe.com)
Further Research Needed
While promising, the study has limitations. It was conducted on neurons in petri dishes (not in living animals) and only measured short-term effects. It’s unknown whether the benefits would persist over time or in full organisms.
The Alzheimer’s mouse model also produces higher-than-natural levels of disease proteins. Further research will need to test these results in live animals and eventually in humans to determine dosing, delivery, and safety.
“More work is going to be required to find the best way to administer this treatment, since a recent clinical trial involving UC Irvine researchers showed that oral nicotinamide was not very effective because of inactivation in the bloodstream,” said lead author Gregory Brewer, adjunct professor of biomedical engineering at UC Irvine, in a statement.
Still, the findings suggest brain cell aging may be more reversible than previously believed. Simple compounds like vitamin B3 and green tea extract could one day help protect brain health and support cleanup processes that falter with age.
Disclaimer: This article summarizes findings from a preclinical study conducted on isolated mouse brain cells in laboratory conditions. The results, while promising, have not yet been tested in living animals or humans. Dosage estimates and potential implications for human health are extrapolations based on standard scientific methods and are provided for informational purposes only.
This content is not intended as medical advice and should not be used to diagnose, treat, or prevent any disease. Always consult a qualified healthcare professional before making changes to your supplement or healthcare routine, especially when considering high doses of vitamins or antioxidants.
Natural Food Sources of EGCG and Vitamin B3 (Niacin)
These foods contain the key nutrients studied in the UC Irvine brain cell energy restoration experiment: EGCG, the antioxidant in green tea, and vitamin B3 (niacin), which the body converts into cellular energy molecules.
Top Sources of EGCG
(Epigallocatechin gallate, per provided EGCG food content table)
FoodEGCG Content (mg per 100 mL or g)Green tea (brewed)70.2–88.9 mg per 100 mLMatcha green tea (powdered)~137 mg per gram (dry weight)White tea42.0 mg per 100 mLOolong tea34.5 mg per 100 mLApple skin (red apple)5.5 mg per 100 gCarob beansTrace amountsHazelnuts & cranberriesTrace amounts
Tip: Brew green tea at 80–85°C for best EGCG retention. Matcha offers the highest EGCG dose by weight.
Top Sources of Vitamin B3 (Niacin)
(From the NIH Health Professional Fact Sheet)
FoodNiacin per Serving% Daily Value*Beef liver (pan-fried, 3 oz)14.9 mg93%Marinara (spaghetti sauce) ready to serve, 1 cup10.3 mg64%Chicken breast (grilled, 3 oz)10.3 mg64%Turkey breast (roasted, 3 oz)10.0 mg63%Salmon or canned tuna (3 oz)8.6 mg54%Peanuts (dry roasted, 1 oz)4.2 mg26%Brown rice (1 cup, cooked)5.2 mg33%Whole wheat bread (1 slice)1.4 mg9%Lentils (½ cup, cooked)1.0 mg6%
*DV = Daily Value, based on 16 mg/day for adults. Fortified cereals can also contain up to 100% of the DV.
Sources:
Paper Summary
Methodology
Researchers isolated brain cells from mice of three age groups (young, middle-aged, and old) from both normal mice and those genetically modified to develop Alzheimer’s-like symptoms. They used a fluorescent sensor called GEVAL to measure GTP (cellular energy) levels in real-time within living neurons. Cells were grown in laboratory conditions for 12-15 days, then treated with nicotinamide (2mM), EGCG (2μM), or both compounds together for 16 hours. Scientists used advanced microscopy to track energy levels, cellular cleanup processes, and protein accumulation before and after treatment.
Results
Aging caused significant drops in cellular energy (GTP) levels, with Alzheimer’s model neurons showing earlier and more severe declines. The combination treatment of nicotinamide and EGCG restored GTP levels in old neurons to match those of young cells within 16 hours. This energy restoration improved cellular cleanup processes (autophagy), cleared toxic amyloid-beta protein clumps, reduced oxidative damage, and increased cell survival by 22%. The treatment also normalized the function of key cellular transport proteins that had accumulated abnormally in aged neurons.
Limitations
The study used isolated mouse neurons in laboratory dishes rather than living animals, which may not fully represent aging in complete organisms. The research examined only short-term effects (16 hours), leaving questions about long-term benefits. The Alzheimer’s mouse model produces artificially high levels of disease proteins compared to human cases. Results need validation in living animals and eventually human clinical trials before therapeutic applications can be considered.
Funding and Disclosures
Research was supported by NIH grant RF1 AG058218 to senior author G.J. Brewer and the UC Irvine Foundation. Lead author R.A. Santana received support from Mexico’s SECTEI for postdoctoral work. Authors declared no competing financial interests.
Publication Information
Title: Treatment of age‑related decreases in GTP levels restores endocytosis and autophagy
Authors: R.A. Santana, J.M. McWhirt, G.J. Brewer
Journal: GeroScience, August 2025
DOI: 10.1007/s11357-025-01786-4