John Hemming's Web Log

An interesting paper was published recently. Intracellular metabolic gradients dictate dependence on exogenous pyruvate This was from the same lab as the excellent paper A non-canonical tricarboxylic acid cycle underlies cellular identity . An interesting question that the paper answers is what drives the need for external pyruvate. The paper concludes "The requirement for pyruvate over lactate can be partially rescued by NAD+, suggesting that at least part of the role of pyruvate in development is regulation of cellular redox62. ". What I find particularly interesting about the link to NAD+ is that Complex 1 (which is reduced in stem cells) has a major role in maintaining NAD+ levels. Hence if it is to be inhibited in some form then something else needs to be done to maintain NAD+ levels. Although Complex 1 maintains mitochondrial NAD+ rather than cytosolic NAD+, depletion in the Mitochondria will block the Malate-Aspartate shuttle affecting the cytosol Pyruvate in th...

Recently another paper was produced which hinted at a link between mitochondrial DNA damage and aging. In fact I have been of the view for some time that the damage to mitochondrial DNA is what drives both aging and development at the lowest level. I have said this before, but thought a summary would be useful. It is worth, however, explaining a few terms first before going into the details of how this happens. It is well known that animals (including people) are made of large number of cells. Within those cells there are little "organelles" called mitochondria that are used to convert nutrients into ATP (Adenosine Tri Phosphate) which is used by cells as a form of energy. There is a hypothesis that is generally believed to be true that this structure of cells arose from some bacteria going into old cells called archea as it created a form of symbiosis where the larger cells provided nutrients to the bacteria for the bacteria to process those. This is called Endosymbio...

The idea that Parkinson's Disease (PD) is an accelerated form of brain aging has been around for quite a long time. However, as with aging more generally any hypothesis as to the mechanisms behind Parkinson's needs to explain all the known research data. I have been discussing PD with a number of people over the past few months. The results from research indicate that Parkinsons is not primarily caused by genetic factors. That is because there are studies where individual twins get Parkinsons, whilst their twin does not. I was wondering, therefore, what might be an alternative cause. This paper is one that substantiates the argument that normally the brain does not age as fast as the rest of the body. What we need to look at is what might cause this to happen. If we start with the assumption from my previous posts that aging results from the mutation of mitochondrial DNA (mtDNA) then we need to find something that prevents the mutation of mtDNA in the brain that does n...

Software Developer and Artifical Intelligence Expert Samuel Collingwood Smith has been working with me on a number of projects for a last few years, mostly in the Artificial Intelligence / AI / bio-hacking space. We entered a number of competitions, some of which were against billion dollar organisations and in one case came in the top-ten with software that runs on a desktop PC, on an nVidia card, against thirty other competitors. As well as using open source AI models hosted in Python, Smith has used his C# and C++ tools to develop his own scratch-written neural network engine, LearnSilver. This is a C# native neural network library that can also execute on CUDA enabled nVidia cards with C/C++, including many gaming graphics cards. It enable significant processing on consumer hardware. It supports training, serialisation of entire models with a single method call and recurrent networks. TALIS is a side, personal project Smith worked on prior to joining me in setting up our new AI c...

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 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...