As we age, there are two major biological events that are also linked to medical conditions: shortening telomeres (the regions with protective features at the ends of every chromosome) and the accumulation of old, malfunctioning cells (senescent cells) in the body. As senescent cells build up and telomere lengths diminish with age, we have a higher risk of experiencing age-related diseases like cancer and cardiovascular diseases.

Efrati and colleagues from Shamir Medical Center and Tel Aviv University in Israel recently published a study in Aging where they used hyperbaric oxygen therapy, exposure to 100% oxygen at elevated environmental pressure, to optimize body tissue oxygen absorption and find its effects on telomere length and senescent cell concentration among human blood immune cells. They found that telomeres grew 20-38% in different immune cell types and that the senescent cell population reduced 11-37% depending on the type of cell.

(Hachmo et al., 2020 | Aging [Albany NY]) White blood cell types show increased telomere length and decreased senescence in humans exposed to hyperbaric oxygen therapy. Top four graphs: All types of white blood cells measured had telomere length (TL) increase from repeated hyperbaric oxygen therapy sessions. Bottom graph: Senescent cell percentages decreased in T-helper white blood cells after 30 and 60 hyperbaric oxygen therapy sessions along with two to three weeks after the 60th session (Post HBOT).

“Today telomere shortening is considered the ‘Holy Grail’ of the biology of aging,” said Professor Efrati in a press release. “Researchers around the world are trying to develop pharmacological and environmental interventions that enable telomere elongation. Our [hyperbaric oxygen therapy] protocol was able to achieve this, providing that the aging process can in fact be reversed at the basic cellular-molecular level.”

The use of hyperbaric oxygen therapy has been shown to increase stem cell proliferation, promote the formation of new powerhouses of the cell called mitochondria, and induce the generation of new neurons. But no previous study had examined the effects of hyperbaric oxygen therapy on telomere length and accumulation of senescent cells.

The Israeli research team exposed 35 healthy people aged 64 and over to a series of 60 hyperbaric oxygen therapy sessions in 90 days. The participants each provided blood samples before, during, and at the end of their treatments and also one to two weeks after the treatment series concluded. The researchers then looked at the length of the telomeres and cellular markers of senescence to determine whether telomeres grew and the percentage of senescent cells in blood immune cells.

“Until now, interventions such as lifestyle modifications and intense exercise were shown to have some inhibiting effect on telomere shortening,” stated Dr. Hadanny, an author of the study, in the press release. “But in our study, only three months of [hyperbaric oxygen therapy] were able to elongate telomeres at rates far beyond any currently available interventions or lifestyle modifications. With this pioneering study, we have opened a door for further research on the cellular impact of [hyperbaric oxygen therapy] and its potential for reversing the aging process.”

The study’s limitations included a small sample size with only 35 healthy, aging participants. They also didn’t compare the results to a group of participants that did not undergo hyperbaric oxygen therapy, a control group. At the same time, the impressive results of telomere length increase and senescent cell clearance with hyperbaric oxygen therapy have not been observed with other interventions. Future studies will need to confirm these effects and evaluate whether similar effects occur in other tissues with this therapy.