In a process called parabiosis, surgically joining a young and old mouse to share circulation revealed that factors in young blood can reverse key aging markers in the brain. This led to reactivated stem cells, reduced inflammation, and improved memory in the older mice.

Only 5% of investigational cancer drugs reach the market due to the gap between lab models and human biology. Dr. Saav Solanki highlights organoids, which use real patient tissue, as a key translational model to improve the predictive accuracy of preclinical research and increase the low success rate.

By converting his blood cells into pluripotent stem cells and growing them into 'organoids' (mini versions of his heart, liver, etc.), Bryan Johnson can test the effects and side effects of new molecules on his own tissues in a petri dish, accelerating and de-risking his longevity experiments.

The technology behind new cell cryopreservatives also enables short-term (3-5 days), ice-free cold storage of complex structures like organoids and organs. This overcomes a major hurdle in their transportation and use, as they traditionally cannot be frozen or held for long periods.

Companies like Cortical Labs are growing human brain cells on chips to create energy-efficient biological computers. This radical approach could power future server farms and make personal 'digital twins' feasible by overcoming the massive energy demands of current supercomputers.

Many major diseases are not separate issues but symptoms of the underlying aging process. By treating aging itself and restoring youthful cellular function, the body can heal itself from conditions previously thought to be incurable.

Biological computing is becoming accessible outside of major labs. Using Python and off-the-shelf components, an independent developer connected 800,000 human brain cells in a petri dish to the video game Doom, successfully teaching the neurons to play. This raises profound ethical questions about consciousness in 'wetware' experiments.

There's a qualitative difference between neurons grown in vitro from stem cells and those found in an adult brain. The scientific community discusses whether lab-grown neurons are less mature, like "infant" neurons, and may lack some receptors. The "perfect" neuron for computation is an open research question.

Shifting focus from amyloid plaque, Dr. Francisco Gonzalez Lima's research suggests viewing Alzheimer's as a vascular disease rooted in mitochondrial dysfunction. This perspective opens new treatment avenues like low-dose methylene blue and photobiomodulation to improve mitochondrial function.