John Hemming's Web Log

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Biohacking Team withdraws from XPRIZE Healthspan - Team continues to work to improve people's health

The Biohacking Team has withdrawn from XPRIZE Healthspan. We think the prize is a really good idea and the science behind the judging is really good. However, we are not willing to sign the competitors agreement. XPRIZE have asked that the competitors agreement be kept confidential and hence we should not give our reasons as to why we will not sign the competitors agreement. Signing the competitors agreement is a requirement for remaining in the contest, hence we need to withdraw. We wish XPRIZE Healthspan well. Finding out what can be done to increase the proportion of people's lives in good health is a really good idea. We have, however, decided to keep the team together. Although the team was brought together to compete in XPRIZE and we are no longer doing that, we have other things to do. We have already participated in the Biomarkers of Aging contest and the Medical Affairs Olympics. We are also running small scale biohacking coaching sessions on both the Diseases of ...

The Electron Transport Chain, DNA and aging - does evolution intentionally expose the Electron Transfer Process to mitochondrial DNA damage?

The Electron Transport Chain has five complexes. These are comprised of a number of subunits. What I find particularly interesting is that some of the proteins are generated via nuclear DNA and some of the proteins are generated via mitochondrial DNA. Most of the ROS (that damages mtDNA) is generated by Complexes 1 and 3. Complex 1 has 45 subunits in humans, but in fact only 7 of those (ND1, ND2, ND3, ND4, ND4L, ND5, ND6) are encoded by the mitochondrial genome. Complex 3, however, has 11 subunits only 1 of which is in mtDNA (MT-CYB) Complex 2 is entirely coded by the nucleus, Complex 4 has 3 (MT-CO1, MT-CO2, and MT-CO3) out of 13 units coded in mtDNA. ATP Synthase also called Complex 5 has 16 units two of which are encoded in the mitochondria. Hence it is clear that complex 1 is perhaps the key complex for mtDNA mutation linked aging and not surprising that this is the complex inhibited in Oocytes. There is an argument that for hydrophobic subunits the energy cost of transferr...

Aging, Development, and Living at High Altitudes (Oxygen Levels)

Oxygen is essential for human life. That is well known. However, the level of Oxygen in the atmosphere has interesting effects. I wrote previously about The Hypoxia Inducible Factor (HIF). HIF (particularly 1 alpha) is a molecule which signals cells to create proteins to build in response to stress. This can involve building new mitochondria or recycling old inefficient mitochondria. In essence it is ringing an alarm that calls for cells to get better prepared for stress. Interestingly HIF is switched on by a drop in the oxygen partial pressure (that proportion of air pressure that is oxygen). It is also well known that if brain cells get too little Oxygen then they can get harmed or die. Hence too low an Oxygen level causes brain damage. In fact there is evidence from people living at high altitudes that at a point the oxygen level is too low and this harms health. However, there is another aspect of Oxygen levels that relates to the mitochondria. The mitochondria produc...

Are we programmed to die?

There are a number of theoretical debates about aging. One is the question of whether we are "programmed to die". Those who believe this think that at a point creatures get to a stage where the organism at a cellular level starts processes which deliberately set out to end the life of the multicellular organism. Another potentially contradictory view is simply that creatures accumulate damage up the point at which they can no longer survive. It is possible, however, to look at different species and see how their lifespan operates. What is clear is that different species age in different ways. Some species don't age in the same way as others. It is worth having a look at how species vary and to what extent that explains the relationship between evolution and lifespan. Firstly, it is clear that there are species where the adult commits some form of suicide after mating. Octopuses and Pacific Salmon There are, however, also species which have negligible senes...

How to fix the Extra Cellular Matrix - Fix the Mitochondria

An interesting paper was published in the week before Christmas. Mitochondrial quality control: the real dawn of intervertebral disc degeneration? The summary states: Intervertebral disc degeneration is the most common disease in chronic musculoskeletal diseases and the main cause of low back pain, which seriously endangers social health level and increases people’s economic burden. Disc degeneration is characterized by NP cell apoptosis, extracellular matrix degradation and disc structure changes. It progresses with age and under the influence of mechanical overload, oxidative stress and genetics. Mitochondria are not only the energy factories of cells, but also participate in a variety of cellular functions such as calcium homeostasis, regulation of cell proliferation, and control of apoptosis. The mitochondrial quality control system involves many mechanisms such as mitochondrial gene regulation, mitochondrial protein import, mitophagy, and mitochondrial dynamics. A large numbe...

Subtle details of mitochondrial DNA are revealed showing the underlying biochemical cause of aging

The fact that mitochondria have their own DNA has been known for a number of decades. However, reading that DNA is harder than the nuclear DNA. That is because there are multiple copies of the DNA in individual mitochondria as well as there being more than one mitochondrion in most cells. However, science has now developed techniques for analysing the mitochondrial DNA in quite subtle detail. In 2024 a number of interesting papers were produced which I will talk about in this post The rate and nature of mitochondrial DNA mutations in human pedigrees is paper produced by a number of researchers in Iceland. The abstract states: We examined the rate and nature of mitochondrial DNA (mtDNA) mutations in humans using sequence data from 64,806 contemporary Icelanders from 2,548 matrilines. Based on 116,663 mother-child transmissions, 8,199 mutations were detected, providing robust rate estimates by nucleotide type, functional impact, position, and different alleles at the same position...