GlyNAC supplementation slows cognitive deterioration in seniors 2023
As people age, they want to avoid cognitive deterioration as much as possible. Baylor College of Medicine scientists are studying the molecular reasons of age-related cognitive decline and developing brain-healthy diets.
In a study published in Antioxidants, researchers found that supplementing with GlyNAC, a compound made of the amino acids glycine and N-acetylcysteine, precursors to glutathione, improved or reversed age-related cognitive decline in old mice and corrected multiple brain defects.
“For over two decades, my lab has been studying natural aging in older humans and aged mice,” said corresponding and senior author Dr. Rajagopal Sekhar, Baylor professor of medicine-endocrinology, diabetes, and metabolism.
“Our work provides an understanding of how age-associated cognitive decline in older humans is linked to glutathione deficiency, increased oxidative stress, mitochondrial dysfunction, abnormal glucose metabolism and insulin resistance, inflammation, and low levels of neurotrophic or neuron-supporting factors, and that supplementing GlyNAC reverses these defects and improves cognition.”
This study addressed aging brain problems in mice because human studies only assess whole body
This study is important because it examines the reversibility of naturally occurring cognitive decline in aging rather than gene-induced cognitive decline; age is the biggest risk factor for Alzheimer’s disease; and these defects were studied directly in the brain.
Sekhar’s team used three mouse groups. Two groups were aged naturally side-by-side until 90 weeks, which is 70 years old. Both groups of senior mice were tested for cognitive ability at 90 weeks, such as remembering the labyrinth route to a food reward. Compared to young mice, the third group. One group of elderly mice had a GlyNAC-supplemented food, whereas the other, the old controls, kept their usual diet.
After eight weeks on their diets, the animals’ cognitive abilities were reassessed and their brains were examined for particular brain abnormalities linked to cognitive impairment in prior research. Old mice fed with GlyNAC were compared to the old-control group and young mice.
“We were very excited with the findings of this study,” Sekhar stated. Old mice experienced cognitive impairment, glutathione insufficiency, increased oxidative stress, reduced mitochondrial function, higher inflammation, genomic damage, and fewer brain-supporting factors compared to young mice.
Importantly, we observed that brain glucose transporters were lacking. The brain’s mitochondria, which burn glucose for energy, were also malfunctioning. These flaws show that the aging brain is energy-starved, which might cause cognitive impairment.
GlyNAC supplementation in aged mice restored brain glutathione, glucose transporters, mitochondrial activity, and cognition. GlyNAC also decreased oxidative stress, inflammation, genomic damage, and neurotrophic factors.
impairment, because similar defects are also reported in these conditions,” Sekhar added. “We’re looking at glutathione deficiency in older people with mild cognitive impairment versus those without.”