In longevity studies, scientists have been getting more interested in the potential antiaging benefits of rapamycin. Currently, this drug is being used to treat specific lung diseases, prevent organ-transplant rejection and coat coronary stents.
Rapamycin was found to extend the lifespan of mice in an experiment in 2009. Since then, numerous clinical studies have been trying to discover the exact contribution and function of rapamycin in longevity and treating age-related diseases.
What is rapamycin?
First, let’s define it. Rapamycin refers to a compound released by a bacterium that is scientifically called Streptomyces hygroscopicus.
Historically speaking, rapamycin was first isolated from a soil sample found on Easter Island in 1972. The name “rapamycin,” in fact, came from the word Rapa Nui, which is the island’s native name. In clinical terms, rapamycin is also referred to as Sirolimus and is being sold under the brand name “Rapamune” [1].
The compound was originally used as an antifungal; however, it is presently commonly used as an immunosuppressant in clinics, which helps prevent organ rejection during transplant surgery–following the 1999 approval of the United States Food and Drug Administration in the use of Rapamune for kidney transplant patients [2].
Moreover, rapamycin is also used as an anti-proliferative that potentially inhibits cell growth, including the growth of malignant or cancerous cells.
How does rapamycin work?
Rapamycin is found to function as a blocker of cells to stop them from growing and multiplying. Consequently, it becomes an effective drug in preventing cancer cells from spreading in the body.
The compound can disrupt cell growth by promoting the inhibition of the mammalian target of rapamycin (mTOR). mTOR refers to a signaling pathway that contributes to cell synthesis and metabolism–basically, rapamycin can interrupt mTOR [3].
The mTOR pathway is known to be involved in the formation of numerous health diseases, primarily different types of cancer and Alzheimer’s disease. With the function of rapamycin, it can potentially treat such fatal health conditions.
Additionally, rapamycin can suppress the immune system of kidney transplant patients in order to keep the body from rejecting the donor’s kidney [4].
Potential benefits of rapamycin
Scientists are still investigating the use of rapamycin for longevity. They are looking at how rapamycin can either slow the aging process or prevent age-related diseases.
Meanwhile, rapamycin’s function in prolonging the lifespan of many species of mice [5], yeast [6] and fruit flies (Drosophila melanogaster) [7] are well-tested and experimented with.
Antiaging benefits
Numerous animal studies have been conducted for years on the effects of rapamycin on dogs, worms, fruit flies, mice and rats, and the results show antiaging potential. However, rapamycin’s beneficial effects on humans are still lacking and being investigated.
The antiaging effects of rapamycin on animal studies are what keep scientists intrigued. Rapamycin can potentially help in preventing age-related diseases, improving the quality of life of patients and extending lifespan.
Furthermore, many scientists believe that rapamycin can be an effective antiaging drug if it is administered to people before they even develop diseases associated with aging. Rapamycin can potentially increase both the health and lifespan of humans [8].
However, rapamycin is not a compound that can magically cure age-related diseases. It can only be a supplement that will be taken alongside a healthy lifestyle and diet.
What is lacking in antiaging studies involving rapamycin? It is determining the actual causes of aging to fully understand the antiaging capabilities of rapamycin.
Some of the major causes of why the body degenerates and develops age-related diseases are a halt in cell division, a loss of stem cells, damaged DNA and shortened telomeres, which are all cell-function related that threaten health and lifespan.
Increases longevity and lifespan
In terms of longevity, rapamycin is found to enhance autophagy, which is a process that removes unnecessary, abnormal and damaged components within cells and prevents cells from stress [9]. In short, autophagy keeps your cells healthy.
Rapamycin can improve autophagy in the body when it inhibits mTOR. It simultaneously boosts the process and disrupts unhealthy cell growth. As a result, the body can delay the onset of the aging process and age-related diseases, giving people a longer and healthier life. Hence, many researchers are positive that we might be able to use rapamycin for longevity in the future.
Used to treat cancer
The mTOR encourages cell growth and proliferation that affects the body’s function to remediate cellular damage through autophagy. When this happens, the body may develop various diseases, including cancer which is the uncontrolled growth of cells.
Interestingly, rapamycin’s ability to inhibit mTOR can also impact tumor proliferation by disrupting it. The inhibition of mTOR through rapamycin induces tumor cell apoptosis or cell death and angiogenesis, which is the process of supplying tumors with the network of blood vessels they need to acquire nutrients.
Rapalogs, which are rapamycin derivatives, are approved in the United States for the treatment of certain types of cancer, particularly renal cancer [10].
Helps with skin aging
The most visible sign of aging can be seen in one’s skin health. Creams made from rapamycin are scientifically produced and prescribed to treat certain skin conditions, such as vascular anomalies, facial angiofibroma and psoriasis in children and young adults. Moreover, rapamycin may also potentially lessen the signs of aging on the skin, including sun spots and wrinkles [11].
Research suggests that topical rapamycin application may reduce sagging skin and photoaging and enhance dermal volume on hands, thereby slowing the process of skin aging. However, a topical rapamycin cream to be added to cosmetics can be far from reality today [12].
Recommended dosage of rapamycin
There is an appropriate dosage of rapamycin, depending on where to use it.
- For kidney transplants – rapamycin should be taken orally by the patients as a tablet or liquid solution for those unable to swallow pills. Your doctor may advise you to take the rapamycin pills with food or a large glass of water or orange juice.
Take note, though, that rapamycin is not safe to take with grapefruit juice and should be taken at the same time and in the same way every day. You should also consult with your physician about the frequency and certain special instructions.
- For cancer patients – rapamycin treatment is commonly given through an IV, and it usually takes around 30 minutes to be administered.
Your rapamycin dose depends on how your body tolerates it, the side effects experienced and the impact on your current medical condition, as per the advice of a medical professional.
Side effects of rapamycin
Using rapamycin may cause side effects and the severity may vary from one person to another. Generally, rapamycin’s side effects are mild but for some, it can be really life-threatening.
Some minor side effects of rapamycin may include:
- A sore or inflamed mouth
- Constipation or diarrhea
- Elevated cholesterol or lipid levels
- Having anemia and experiencing fatigue
- High blood pressure
- Swollen hands and feet
- Weakened immune system
Possible major side effects of rapamycin may include:
- Headache
- Fever and nausea
- Chest pain
- Stomach pain
- Muscle aches
- Dizziness
- Blood clots
- Stroke or pulmonary embolism
- Blood clotting problems
Additionally, some people are not recommended to use rapamycin because it may be unsafe for them. The following must not take rapamycin:
- Pregnant or breastfeeding women
- Individuals who are sensitive to rapamycin
- Lung transplant patients due to increased risk of serious complications
Risks to health and longevity
While rapamycin may help kidney transplant patients, it may increase the risk of infection for some other people as it can notably suppress the immune system. Suppressing the immune system brought by rapamycin may significantly impair wound healing.
Some other risks of using rapamycin include insulin resistance, high cholesterol and interstitial lung disease. Using rapamycin can have negative effects on glucose metabolism that may cause diabetes-like effects.
Most importantly, the greatest risk of taking rapamycin as an antiaging drug is the lack of human research. There is still no strong evidence from clinical trials that may prove its health and longevity claims, especially when taken over a long period of time.
As mentioned several times before, there are many successful research studies on animals in relation to rapamycin’s antiaging effects; however, there are only a few human studies to back it up.
Not to mention, few human studies have mostly been conducted among small groups of patients and treatment regimens vary significantly between studies. Hence, there are still inconsistencies among the results.
Although, some scientists may argue that there may be little to no risk of adverse effects from using rapamycin to fight aging; however, we still can’t determine how much rapamycin should we take and when to schedule and the varying effects of these two variables on a person.
One thing we know for sure is that rapamycin has the potential to prolong longevity, improve quality of life and slow down aging but it is still early to celebrate yet.
[1] https://pubmed.ncbi.nlm.nih.gov/12742462/
[2] https://www.accessdata.fda.gov/drugsatfda_docs/nda/99/21083A.cfm
[3] https://www.uptodate.com/contents/pharmacology-of-mammalian-mechanistic-target-of-rapamycin-mtor-inhibitors
[4] https://pubmed.ncbi.nlm.nih.gov/33037985/
[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3434687/
[6] https://pubmed.ncbi.nlm.nih.gov/19458476/
[7] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2824086/
[8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6814615/
[9] https://www.sciencedirect.com/science/article/pii/S0014579310000360
[10] https://aacrjournals.org/mct/article/15/3/347/92052/The-Enigma-of-Rapamycin-DosageRapamycin-Dosage
[11] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6949048/
[12] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6925069/
