Let’s think about what happens in response to a starchy meal. Blood sugar rises and insulin is released. Insulin attaches to the insulin receptors on the cell membranes of muscle cells, fat cells, etc. The cells respond by moving a glucose transporter, GLUT4, into the cell membrane so that they can start importing glucose. Insulin …
Physiological Insulin Resistance Read More »
In the introductory series, we first saw an example of ROS (Reactive Oxygen Species) as a signal in a small worm (nematode) called c. elegans. When glucose oxidation in c. elegans is blocked, the worms shift to burning fat which creates more ROS which ultimately leads to a longer lifespan for the worm. Why does …
A Highly Conserved Molecular Bottleneck Read More »
A mitochondria works like a battery. It maintains a voltage gradient across its inner-membrane. The outside of the membrane has a positive charge and the inside has a negative charge. Protons from the outside flow back through the membrane down the gradient, releasing energy, through a large cross-membrane protein complex called ATP synthase, which uses …
AKA The Layperson’s Guide to Hyperlipid This series is going to be exploring the root cause of obesity and how energy balance is controlled at a cellular level. My thinking on this subject has been heavily influenced by Peter at Hyperlipid and his protons theory. His writing is dense, technical and full of acronyms. I …
The ROS Theory of Obesity Read More »
If you’been reading through the Introduction to Fire in a Bottle series, I explained the concept of oxidation, discussed the oxygen catastrophe and its implications for evolution, I introduced our unlikely hero superoxide and then we met our bodies inbuilt antioxidant defense system. Along the way I introduced the key point that Reactive Oxygen Species …
Two Elegant Experiments Demonstrating that ROS is The Signal Read More »
Oxidation (in a biological context) is the flow of electrons from elements like Hydrogen and Carbon to Oxygen Oxygen is very reactive. Chlorophyll took its electrons away and it would very much like to get them back. In metabolism – the oxidation of starch and fat – free radicals, notably superoxide, are produced from Oxygen. …
Summary of The Introduction to Life in a Bottle Read More »
When I took oncology at Cornell in the mid-90’s, the root cause of cancer was explained in the following way. Certain things – such as ionizing radiation from a nuclear explosion – cause free radical formation. The free radicals can damage the DNA, causing genetic mutations. When enough mutations accumulated in key genes affecting the …
Superoxide: An Unlikely Hero Read More »
The primordial atmosphere of the earth didn’t contain Oxygen (O2). The atmosphere was a “reducing atmosphere”, the exact opposite of today’s “oxidizing atmosphere”. Somewhere along the line life evolved. Single-celled organisms. Weirdos by today’s standards. Methanogens and sulfate-reducing microorganisms. That was just life for a couple billion years. And then chlorophyll evolved. Chlorophyll changes everything. …
The Great Oxygenation Read More »
In the previous post, we introduced our unlikely hero superoxide, a free radical. We also introduced peroxide and the term “Reactive Oxygen Species” (ROS), the term that refers collectively to superoxide and peroxide and others in the family of pro-oxidant molecules. We evolved to thrive in the presence of oxygen and ROS after the Great …
Meet Your Antioxidant System Read More »
Fire is a positive feedback loop where atmospheric oxygen (O2) oxidizes the hydrocarbon bonds (the bonds between a carbon and a hydrogen atom) in common fuel sources like wood, paper, fat, cellulose, starch, sugar, natural gas and gasoline. The oxidation reaction gives off heat. The heat causes more oxidation which causes more heat which causes …
Humans are electrical creatures. Our basic biology is controlled by the movement of electrons. In a biological system, instead of moving through a wire, the electrons move from one molecule to another. These reactions are called redox reactions, which is short for reduction and oxidation. when an electron moves from one molecule to another, the …
A Very Gentle Introduction to Oxidation Read More »
