Mice given alpha-ketoglutarate (AKG) supplements were reported to be healthier as they aged, and female mice lived longer than those not given the supplement, according to the researchers at the Buck Institute for Research on Aging.
“The big thing about this is that its safety profile is so good,” says the University of North Dakota aging researcher Holly Brown-Borg, who was not involved with the study. “It has potential and should be explored further, for sure.”
AKG is naturally made in both mice and human bodies, and it is already considered to be safe by regulators. It is part of the metabolic cycle that cells use to make energy from food; sometimes it is used to treat osteoporosis and kidney disease, along with some bodybuilders to bulk up.
In 2014 researchers discovered that this molecule may have an anti-ageing possibility when a study published in Nature reported that it helped to extend the lifespan of C.elegans by more than 50%; and other studies showed it improving lifespan in fruit flies.
AKG levels will gradually decline with age, as such the researchers are looking for ways to restore levels to those seen in younger years. In this study published in Cell Metabolism 18-month-old mice, which is the equivalent of around 55 human years, were given AKG as 2% of their daily feed until they died or for up to 21 months, recording all changes.
Within a few months: “They looked much blacker, shinier, and younger” than control mice, says Azar Asadi Shahmirzadi, a postdoc at the Buck Institute who did the experiments as a graduate student. Animals in the AKG group also scored on average 40% better on tests of frailty as measured by 31 physiological attributes including walking gait, grip strength hearing, and hair colour. Additionally, female mice in the AKG group lived a median of 8-20% longer than the controls. It was noted that the mice in the AKG group did not perform better in tests for heart function or treadmill endurance, and they did not test for cognitive improvement.
Female mice in the AKG group were found to produce higher levels of a molecule that fights inflammation. Although these effects on health and longevity were smaller for AKG than for some other anti-ageing compounds, some of the other compounds have had safety issues, for example, rapamycin can suppress the immune system and may promote diabetes.
The researchers plan to test AKG in human volunteers in the near future, possibly in a group of people between the ages of 45-65 to investigate whether the molecule will improve ageing-related biomarkers such as inflammation, arterial hardening, and chemical signatures on DNA that are associated with ageing.