Today, more people are experiencing increased longevity as compared to past generations. Despite the benefits, this extended lifespan often leads to accumulated ailments common in old age, such as dementia, cancer, and more. Geroscience, a newly founded discipline, addresses primary factors of ageing, striving to defer the advent of diseases and impediments that can render old age wretched. The field attempts to confine these typical old-age diseases into a much briefer duration. This philosophy was further elaborated on by Cassandra Willyard in Science News and Richard Faragher in The Conversation, both in January 2021.
A notable turning point in history was the leap in the average human lifespan from about 30 years in the 1800s to over 70 years presently. This increase is largely due to advancements in scientific medicine and public health. This global population ageing is indeed a substantial shift.
Statistics from the United Nations, cited by Willyard, reveal that by 2030, one billion individuals will be 65 or older. By the end of the century, this number is projected to rise to five billion. Alongside this growth in lifespan comes a surge in age-related diseases such as type two diabetes, cancer and more. These demographics pose a significant strain on our health care and elder home facilities.
As we age, our fundamental biological structure declines, which results in a weaker immune system, making us more prone to diseases. There is also the development of diseases such as heart disease, dementia, type two diabetes, and more. Consequently, most people spend the closing years of their lives grappling with one or several of these diseases. This necessitates the development of new drugs to ensure the elderly remain healthy, self-reliant and lively for a more extended period.
Up until a short while back, the medical fraternity believed that the decline in health and capability during old age was unavoidable. Nonetheless, studies in the ’80s and ’90s gave rise to optimism that ageing could be controlled when they discovered that certain gene mutations in roundworms doubled their lifespan. Furthermore, the repurposing of drugs initially intended to treat conditions unrelated specifically to ageing as anti-ageing medication offered further hope. Rapamycin and metformin are prime examples of this practice.
The medication Rapamycin is often given to individuals who have undergone transplants to assist their immune systems in receiving the new tissue. Known for reducing inflammation, eliminating worn-out and damaged cells, and modifying metabolism, the drug addresses several aspects believed by researchers to contribute to the ageing process. Studies have illustrated that Rapamycin not only extends mice’s lifespan by 15%, but also significantly enhances immune function and vaccine reactions in older people.
Metformin, initially introduced as a treatment for type two diabetes, has over the years demonstrated additional benefits. Observations indicate that Metformin users experience less mortality and sickness compared to those who do not use the drug. The drug achieves this by reducing inflammation instigated by senescent cells. The promising performance of similar drugs, coupled with their safety proven by significant investments, gives them substantial superiority over newly discovered drugs.
Senescent cells are cells that cease dividing while maintaining their vitality in elderly individuals. Consequently, they disturb the normal metabolism of their surrounding tissues, induce additional senescence in adjacent cells, release inflammation-inducing chemicals, and obstruct tissue repair. Senolytics, a category of drugs designed to eradicate senescent cells by promoting programmed cell death, include Fisetin, a flavonoid prevalent in fruits and vegetables, with strawberries having an especially high content. Results in mice studies have shown promise, with human trials in progress to confirm these findings.
The investigation of potential anti-ageing drugs often begins with organisms such as yeast, worms, and mice. Their short lifespans enable quicker extraction of trial results. However, human trials, although time-intensive, are crucial for conclusive results, therefore necessitating a gradual progression of geroscience.
In view of the impending revolution in geroscience, we currently have practical guidance to enhance our healthspan. This includes maintaining a balanced diet, engaging in sufficient aerobic and resistance exercises, staying up-to-date with vaccinations, abstaining from tobacco, and consuming alcohol in moderation.
William Reville is a retired biochemistry professor at the University College Cork.