Researchers from Baylor College of Medicine in Houston have recently published a study that reveals supplementation of glutathione can extend lifespan by 24% in mice, both male and female: 129 vs. 104 weeks. These results were among the best achieved in mice.
GlyNAC Promotes Healthy Aging In Humans
However, these same researchers conducted a pilot study in humans in 2021 using GlyNAC (a blend of glycine and N-Acetylcysteine “NAC”) as a precursor to naturally occurring antioxidant glutathione (GSH) where it improved many age-related deficiencies in older people, such as improved muscle strength and cognitive function and benefited healthy aging.
In the study, participants treated with GlyNAC for 24 weeks experienced significant improvements in many aging-related characteristics, such as,
- exercise capacity
- glutathione deficiency
- oxidative stress
- muscle strength
- cognitive function
- endothelial dysfunction
- mitochondrial dysfunction
- gait speed
- insulin resistance
- body fat
- genomic toxicity
The study suggested that GlyNAC supplementation could be a viable and straightforward method to promote and improve healthy aging in older adults.
Researchers called it the “Power of Three” because the benefits of NAC, glutathione, and glycine are combined to enable such wide-ranging and overall improvements.
The clinical trial results were published in Clinical and Translational Medicine. The scientists revealed that supplementing with GlyNAC could improve older adults’ mitochondrial, metabolic, and cellular health, increase their strength and cognition, and thus extend their life expectancy.
Their research emphasized that mitochondrial dysfunction and oxidative stress contribute significantly to aging. Cognitive and physical decline are associated with aging in older adults, including increased inflammation, endothelial dysfunction, insulin resistance, and central obesity. These defects in older people are not fully understood, and effective interventions to reverse them are either not available or severely limited.
How GlyNAC Impacts The Hallmarks Of Aging
Scientists have identified nine hallmark flaws contributing to aging to understand what causes unhealthy aging. These hallmarks of aging are:
- telomere attrition
- mitochondrial dysfunction
- altered intercellular communication (which includes inflammation)
- genomic instability
- stem cell exhaustion
- dysregulated nutrient sensing (which includes insulin resistance)
- epigenetic alterations
- cellular senescence
- loss of proteostasis
Researchers believe improving or reversing these aging hallmarks could help people age more healthily and improve many age-related disorders.
The causes of these hallmark defects are not fully understood, and currently, there are no solutions to fix even one of them.
Scientists involved in the clinical trial have been studying natural aging for more than two decades now, in both humans and mice.
The mitochondria and aging have been linked in their previous work. In age-related mitochondrial dysfunction, they believe, improving mitochondrial health is crucial. Mitochondria produce the energy necessary to support cellular functions by burning fats and sugars from foods, so mitochondrial health is essential for survival.
Whenever mitochondria generate energy, waste products like free radicals are created. In addition to damaging cells, membranes, lipids, proteins, and DNA, these molecules are highly reactive. To neutralize these toxic free radicals, our cells depend on antioxidants, such as glutathione, our most abundant antioxidant.
Fuel oxidation generates toxic reactive oxygen species (ROS), causing oxidative stress. To protect mitochondria from oxidative stress, antioxidants are necessary.
Oxidative stress can damage mitochondria when free radicals are not neutralized. Older people have much lower glutathione (GSH) levels than their younger counterparts, and oxidative stress levels are also higher.
These same researchers previously showed that glutathione deficiency in mice, even in their youth, was associated with mitochondrial dysfunction. And that restoring glutathione levels by supplementing them with GlyNAC reversed the glutathione deficiency, prevented oxidative stress, and restored mitochondrial function in aged mice.
Past research also indicated that supplementing HIV-infected patients with GlyNAC improved multiple deficits associated with premature aging.
In this particular clinical trial, the scientists wanted to determine whether GlyNAC supplementation affected aging-related conditions in older people and whether it could help with mitochondrial regeneration.
Study participants included eight older adults between 70 and 80 years of age and gender-matched younger adults between 21 and 30.
They specifically measured the following:
- mitochondrial fuel-oxidation
- glutathione in red blood cells
- endothelial function
- plasma biomarkers of oxidative stress and oxidant damage
- glucose and insulin
- muscle strength
- muscle-protein breakdown rates
- exercise capacity
- body composition
- cognitive tests
NOTE: Before administering GlyNAC, all these measurements were abnormal in the older group compared to the younger one.”
For 24 weeks, the older participants took GlyNAC, followed by a 12-week break. The measurements mentioned above were retaken after 12 weeks of GlyNAC supplementation, after 24 weeks, and after stopping it for 12 weeks.
There were no adverse effects during the study period. Of interest, the benefits of GlyNAC supplementation decreased after 12 weeks.
Despite this finding, continuing supplementation with GlyNAC for 24 weeks enhanced four out of the nine hallmarks of aging (mitochondrial dysfunction, insulin resistance, inflammation, and genomic damage).
These findings indicate that GlyNAC supplementation in older adults is well tolerated and could play a critical role in prolonging healthy aging by repairing mitochondrial dysfunction, GSH deficiency, oxidative stress, muscle strength, gait speed, inflammation, insulin resistance, endothelial dysfunction, body fat, and cognitive function.
Their findings surprised them. These deficiencies in older adults improved after taking GlyNAC for 24 weeks. In some cases, the levels even reversed to those of young adults, especially improvements in cognition and muscle strength.
Mild cognitive impairment (MCI) and Alzheimer’s disease are severe medical conditions that affect memory in older people, and neither of them can be effectively treated. The researchers are looking at the possibility of GlyNAC supplementation improving cognitive defects related to Alzheimer’s disease and MCI and possibly improving cognitive function in two upcoming pilot randomized clinical trials.
GlyNAC is shown to be safe and is already sold as a supplement, although more research may be needed to establish its effectiveness in humans.
The results may be even more fascinating if GlyNAC is integrated with NMN or calorie restriction. According to these studies, GlyNAC may become one of the most promising supplements for extending life.