Senescent Cells A Cause Of Aging
Senescent or old cells are a major feature of the aging process, and finding a way to deal with them can help promote health and younger looks. Researchers reported in a recent study that the immune system could be of great help in this regard.
Findings made in a new study done at the Weizmann Institute of Science showed that an efficient immune system may be an answer to aging and for promoting a youthful appearance. These were published in the journal Nature Communications.
The researchers led by Prof. Valery Krizhanovsky were interested in knowing what role the immune system can play in dealing with old cells that accumulate in the body as people grow older.
The use of a certain protein was found to enhance the ability of the immune system to clear away the aging-inducing cells.
Combating senescent cells
It has been long since researchers became aware of the role of senescent cells in the aging process.
There are different reasons cellular senescence may occur. The most prominent one has to do with the Hayflick limit. This phenomenon sets in when somatic cells reach their replication threshold.
Senescence also does occur as a means of guarding against the development of cancer. It prevents cells from replicating and renders those that can turn into tumors inactive.
The immune system assists in clearing away these old cells. The cells also do get destroyed through programmed cell death mechanisms.
However, some of these cells may refuse to be eliminated from the body while remaining metabolically active.
The inflammatory and other signals they produce can adversely affect tissue structure and function over time. This explains why older people often battle with inflammatory and age-related disorders.
Senescent cells have, therefore, been the target of many anti-aging researchers. These believe that effectively dealing with the cells could help rejuvenate the body.
Getting rid of old cells with the immune system
In the current research, scientists used a mouse model to investigate how the immune system may help against senescent cells.
Mice that were lacking the perforin gene were found to have greater amounts of old, ineffective cells in their bodies. As a result, they suffered from reduced functions and had more chronic inflammation. They also suffered premature deaths, compared to their healthy counterparts.
The researchers observed that the protein perforin was vital to the function of the immune system. It especially helps in getting rid of senescent cells. This was why mice with low amounts had more of these cells and developed age-related disorders more.
The animals with a silenced perforin gene were administered with an experimental drug called ABT-737, one of the pharmacological inhibitors of BCL-2 proteins. The substance, which was originally developed for cancer treatment, blocks certain proteins that keep senescent cells from dying.
Elderly mice that were experiencing issues due to the accumulation of old cells in their body responded impressively to the drug. The number of problematic cells in their bodies reduced significantly.
The improvements seen in the treated mice made them more like younger, healthy mice. Their tissues became almost like those in the latter group. They became more active and their lifespan, on average, increased.
A major concern, though, is the potential of ABT-737 to cause unpleasant side effects. This is a reason it has yet to be made available for cancer treatment in humans.
The main point in this new research, however, is that therapies that boost the immune system and its ability to eliminate old cells may help combat aging.