Our society is fascinated by youth and aging. But while some people are on a quest for the “magic” youth cream, there’s a small group of children who actually battle a serious and fatal aging condition known as progeria. In a
recent report in the journal of
Aging Cell, scientists showed that a common chemical, methylene blue, may be a promising drug candidate for progeria treatment.
Known formally as
Hutchinson-Gilford progeria syndrome, this rare genetic condition is often described as accelerated aging. Afflicted children show signs and symptoms of abnormal aging beginning in their first year of life. The skin thins and wrinkles, hair falls out, bones and joints ache, organs fail – the entire system is so fragile that affected children resemble old, aging people. Most progeria patients do not reach adulthood and can barely survive their teenage years.
The most common causative mutation of progeria is found in the
LMNA gene, and results in a defective protein product called progerin. In mutated cells, progerin accumulates and affects the structural integrity of the nuclear envelope, ultimately leading to early cell death.
In addition to deforming the nucleus, the mutated protein also damages the mitochondria, a source of energy for the cell. In patients, the misshaped nature of the mitochondria – swollen and fragmented – prevents normal cellular functions to be carried out.
While most progeria research has been largely focused on the nucleus, researchers at the University of Maryland took a different approach and looked at the defective mitochondria. They treated progeria cells with methylene blue, a potent antioxidant, and noted that both the nucleus and mitochondria of these cells reversed to normal shape. They also showed that methylene blue freed the mutated progerin protein from the nuclear membrane and corrected the abnormal gene expression in progeria cells.
The researchers picked methylene blue based on its antioxidant nature. Damaged mitochondria release a substantial amount of reactive oxygen species (ROS), molecules that oxidize DNA, proteins, and lipids. This cumulative oxidation is known to contribute to the aging process, and too much may accelerate aging in progeria. Thus, they reasoned that treating progeria cells with an antioxidant may have positive effects.
Methylene blue is not a new drug, having been around for 140 years. Other researchers have shown that this compound can
delay cell death in cultured systems. But the compound is actually more widely known as a cheap antifungal for fish and
a fish tank cleaner. How this common compound reverses cellular aging is still being worked out.
This is such an exciting result with so much potential, both for progeria and normal aging. Methylene blue is common and inexpensive. It is fully water soluble and non-toxic. People use it to clean fish tanks because it is so safe for the fish eggs. – Zheng-Mei Xiong, lead author of the study.
But a word of caution before anyone thinks methylene blue is the long-awaited cure for aging: this study was done only in cells. The team will next conduct studies of methylene blue in animal models, asking whether the same cellular effect can be observed, and if so will it contribute to aging and survival length. In addition, just because it’s safe for fish doesn’t mean it’s safe for humans. So the team will have to carefully note any adverse effects of this drug on animal models aside from fish.
So far, we have done all of our work in stem cell lines. It is critical to see whether the effect extends to whole animal. We also want to see if methylene blue can repair specific effects of progeria in various cell types, such as bone, skin, cardiovascular cells and others. Further down the line, other groups might begin human clinical trials. – Kan Cao, senior author of the study.
Listen to the story of Sam Bern, a beloved progeria patient, and learn how he inspires a happy life despite the progeria diagnosis.
