31st January 2026 Newsletter
Hi guys. This is the thirteenth newsletter from the Rejuvenation Science Institute (ICR). In these newsletters, we will tell you what we've done, since the last newsletter, to accelerate the development of rejuvenation science.
We have completed the funding for the Rat Rejuvenation Experiment
During January 2026, we managed to raise the US$75,000 needed to carry out the Rat Rejuvenation Experiment, one year after we started the fundraising campaign for it. This experiment, which will be conducted starting in April 2026 in collaboration with the university Unicamp, aims to assess whether PPEPs (Pig Plasma Extracellular Particles) from young animals can rejuvenate elderly Sprague Dawley rats (or slow down or stop their aging), in addition to evaluating their effect on young rats.
PPEPs are a fraction of pig plasma that contains small extracellular vesicles — commonly called exosomes — as well as other nanoparticles. PPEPs were originally isolated by Harold Katcher and colleagues in an experiment in which the injection of these particles led to the best epigenetic rejuvenation results in mammals ever published.
Thus, the ICR aims to replicate this experiment in order to verify whether mammalian rejuvenation was indeed invented, as extraordinary claims require extraordinary evidence. Furthermore, this is how science is done; experiments need to be replicated by third parties, as publication alone does not establish something as scientific truth.
The ICR's experiment also has some differences from Harold Katcher's original experiment: we will use 10 rats instead of 6 in each group — a larger N. In addition, we will have not only a group of treated old rats, but also a group of treated young rats, to assess whether the treatment can keep them young. Finally, we will measure epigenetic age before and after treatment, so that the comparison will not only be with the control group, as in the original experiment, but also with the group itself.
We would like to thank everyone who donated to the ICR to make this experiment possible, and everyone who helped in other ways. In particular, we are grateful to DoNotAge.org, for donating US$25,000, and to Heales, for donating US$10,000. We ask those who currently make recurring donations to continue doing so, because although we have completed the funding for this experiment, we will certainly have additional costs due to the fact that, at the end of the experiment, until all analyses (epigenetic and non-epigenetic) are complete, we will not be able to make a decision on whether or not to conduct the Rat Longevity Experiment (which will only be conducted in full if the rats rejuvenate, or if their aging is slowed or halted in the Rat Rejuvenation Experiment). Therefore, we will have to at least start the Rat Longevity Experiment anyway, including injecting another dose of PPEPs into the rats. In any case, once we are sure that the Rat Longevity Experiment will be carried out in full — which basically consists of letting the rejuvenated rats live and be treated until they have (or do not have!) a natural death — we will open a crowdfunding campaign for the Rat Longevity Experiment, and we will include the funds donated to the ICR after the Rat Rejuvenation Experiment funding campaign closed.
The experiment will start in April, not June
Since January 2025, the Sprague Dawley rats have been aging in the university Unicamp animal facility so that we can use them in the experiment. Harold Katcher and his collaborators used 25-month-old rats. In our reproduction of Katcher's experiment, we will need 20 rats of that age: 10 will be from the treated group and 10 will be from the control group. However, during this period of approximately one year in which they were aging, some of the animals that were set aside for this purpose died of natural causes. Since we knew this could happen, we had 42 aging rats initially, not just 20. So, in order to ensure that we have 20 old rats for the experiment, we decided to bring the experiment forward by two months, so that the animals will be 23 months old, not 25, when they receive the first dose of treatment. This difference is relatively small, considering that 23 months is already a very advanced age for rats, and this change will give us more certainty that we will have the desired N for the experiment.
Veterinarian hired
An important part of the Rat Rejuvenation Experiment is the collection of blood from young pigs, since the PPEPs will be isolated from this blood. This requires the services of a veterinarian specialized in pigs to perform the collection at the pig farm, in addition to assessing the overall health of the animals before slaughter and collection in order to confirm that they are healthy. After months of searching, we were able to find a qualified professional who agreed to work with us.
Meeting with our university Unicamp collaborators
In January 2026, the ICR held its first in-person meeting of the year with our university Unicamp collaborators. The Rat Rejuvenation Experiment will be conducted mostly at the university Unicamp, in the Laboratory of Aging Biology, coordinated by Professor Marcelo Mori, PhD, from the Institute of Biology. The meeting was attended by the university Unicamp team that will participate in the experiment, and we made several alignments regarding the experiment schedule, the supplies to be purchased, the details of PPEPs isolation, and the next steps to be taken.
This is a collective effort
This experiment is a collective effort to reproduce Harold Katcher's seminal study, in which the ICR relies on the contribution of those interested in the realization of the experiment. Thus, if you know someone who might be interested in the content of this newsletter, you can forward it to them. Also, if you are not yet a financial contributor of the ICR, we invite you to become one by clicking on this link.
So that's it. We're carrying on, and we won't rest until we've implemented rejuvenation in human beings. See you next time!