Monday, May 16, 2022

Deuterium protected linoleic acid

This is a fascinating paper which has distracted me from my thought train on uncoupling, mitochondrial membrane potential and ROS generation because it has aspects involving all three while not being particularly intuitive as to what is going on. I picked it up via comments from Tucker and Raphi on twitter.

Deuterium-reinforced polyunsaturated fatty acids protect agains atherosclerosis by lowering lipid peroxidation and hypercholesterolemia

First aside: Mouse model. This current model, the APOE*3-Leiden mouse, is a model. It's not as totally useless as an APOE total knockout or an LDL receptor knockout model but it's still nothing like a real mouse or like a real human. Mouse lipoprotein management is not like human lipoprotein management. They do not have a cholesterol ester transfer protein. The Leiden mouse has this human gene engineered in. It also has a selective APOE*3 knockout to give a mild elevation of LDL. The end result is a model which has numbers on a lipid panel which look a bit more like a human with metabolic syndrome than the average extreme knockout mouse model.

But it's not a human with metabolic syndrome. It's an APOE*3-Leiden mouse and if you found a cure for its "atherosclerosis" you would have a great tool for helping APOE*3-Leiden mice. Would it translate to helping humans with metabolic syndrome? Hahahahahahahahah bonk. End aside.

Second aside: Does LDL cause atherosclerosis? Hahahahahahahah, bonk. To anyone with any sense atherosclerosis is a response to injury where IGF-1 delivered by platelets attaching to the injured endothelium causes media hypertrophy to reinforce the site of injury. This is accelerated if systemic hyperinsulinaemia also acts as an agonist on those IGF-1 receptors. It can almost certainly be enhanced by delivering lipid peroxides such as 4-HNE, 13-HODE and 9-HODE, though their effects are very, very complex. I'm perfectly willing to believe that any genetic engineered tweak in to a mouse which increases the persistence of linoleic acid containing lipoproteins in the plasma allows time for that LA to spontaneously oxidise and accelerate what looks a bit like atherosclerosis, in the model. Just my view. End second aside.

OK. On to the paper:

The APOE*3-Leiden mice were reared on non specific chow. At 12 weeks of age (Time -4) they were put on to something derived from the AIN-93M diet. All lipids were all supplied as methyl esters of fatty acids, not triglycerides. It contained 1.2% of calories as LA and 9% of calories as sucrose. The intervention group had exactly half of the 1.2% of LA calories supplied in the form of deuterium stabilised, ROS peroxidation resistant D2-linoleic acid.

They were fed these diets for four weeks. At that point (Time zero) 0.15% by weight of reagent grade cholesterol was added to both diets (otherwise the model doesn't work to get the essential-for-funding lipid lesions, no sniggering at the back. It's a model). This "western" diet, which only differed from the run-in diet by the added 0.15% reagent grade cholesterol, caused/allowed some weight gain over the following 12 weeks but less in the D2-LA supplemented group than the normal LA group:

No weight gain on either of the run-in diets, followed by lots of gain in the "normal" LA diet but not the D2-LA diet once the cholesterol was added.


Why should adding 0.15% of cholesterol produce such diverging weight gains?

Even more exciting is if you look at lean mass vs adipose mass:

Adding just 0.15% cholesterol produced a marked fat mass gain in the normal LA mice and a trend downward in fat mass for the ROS protected D2-LA mice.

On top of that the D2-LA mice started eating extra during the period of fat loss. A lot extra:

Soooooooo. What is going on?

Well, the first thing to realise is that during the four week run-in period after the replacement of chow by the AIN-93M derived diets there were already changes which didn't show in total body weights (graphs A and B). The mice, with or without deuterium stabilised LA, all lost muscle mass and all gained fat mass during those weeks, just under a gram of each. So, even without the reagent grade cholesterol, changes were already on going from a "normal" mouse phenotype on chow towards a "skinny-fat" phenotype on an AIN-93M-like diet. That's clear in graphs C and D. Possibly from the sucrose but there's no way of telling that from the paper.

The changes were on-going before the diets were "westernised" by the addition of 0.15% of reagent grade cholesterol. I suspect that the addition of the cholesterol is a red herring.

Let's go on to look at food intakes.

The mice on the deuterated LA eventually began eating more than those on the standard LA. This became statistically significant at about week five.

Any mouse which is eating extra and losing adipose tissue is either showing malabsorption or uncoupling.

I'll buy the uncoupling, but then I would.

Why the delay to the onset of starting to eat extra? Is there a delay in uncoupling onset? Not necessarily. A normal mouse uses a significant percentage of its caloric intake to generate heat in its brown adipose tissue. There is no need to increase food intake while ever the purported uncoupling from deuterated D2-LA is generating less heat than is needed to maintain body temperature. As heat production increases over time it begins to exceed this essential minimum and so comes to represent a "calories-out" in excess of what is merely needed to keep warm. At this point an increase in food intake becomes necessary to balance the heat lost by supra-physiological uncoupling.

If this is correct, and that's a big if, there is clearly an on-going progressive increase in uncoupling with time. The logical explanation is that there is a progressive increase of deuterated D2-LA in tissues and/or being used for beta oxidation.

How might deuterated, ROS resistant LA, facilitate uncoupling?

I don't know, so it's time for some routine wild speculation. If we could answer that one question the whole scenario becomes straight forward. Sadly it is not at all obvious why D2-LA should facilitate uncoupling. Here's my current best shot. If I think of something more plausible I'll post again:

Let's assume that linoleic acid, whether deuterated or native, allows excess calories in to a cell. This is the doodle from a few posts ago:

which then leads to this doodle:

and this doodle:

This begs the question as to how much damage (signalling?) is done by the stray electrons, how much by superoxide, by hydrogen peroxide or how much is actually mediated by the lipid peroxides generated from linoleic acid per se. Which is the most important mediator?

Let me suggest that D2-LA allows the excessive delta psi, which facilitates both reverse electron transport and pathological ROS generation. As in the previous post the high delta psi eventually allows D2-LA to drive RET at the cost of, via high delta psi, allowing electrons to be lost from the ETC to oxygen at abnormal sites, forming superoxide. Under D2-LA this superoxide has very limited ability to contact oxidisable native linoleic acid.

So now we look more like this with ;

There is a surfeit of ATP, high delta psi and availability of either LA and/or D2-LA to facilitate uncoupling combined with minimal damage to the ETC. You do have to have a source of 4-HNE or a related "damage marker" to facilitate uncoupling but it doesn't need much.

I can't see any more straightforward technique for D2-LA to uncouple. If there is one and it's clear how it works, that would be great. Currently this is the best I can do.

Summary: D2-LA allows uncoupling. That explains everything, but the mechanism for the uncoupling is obscure and I'm guessing.

NB I was also trying to explain to myself why the control group got fat. I don't think they did. A total weight gain of 5g over 12 weeks to give a final weight of 25g sounds like a normal mouse to me. It's the slim mice eating extra food to maintain that slim bodyweight that are abnormal.

Ultimately the paper poses the question: What determines whether a cell deals with excess calories by sequestration to storage vs uncoupling. Obviously this is insulin signalling. But is it an oxidation product of linoleic acid which controls insulin signalling? Are we simply looking at a situation of absolutely suppressed insulin signalling, due to D2-LA being "too" stable?


Final addendum/aside. There is a claim on 'tinternet, un referenced, that low dose oral deuterium oxide in mammals causes weight loss, rather than the death which is the normal result of high dose exposure. Could D2O trigger uncoupling irrespective of LA type and the catabolism of D2-LA be a simple source of deuterated water by oxidation of the D2-LA? I doubt this but the idea is still a potential explanation. I have hunted support/refutation for this without success.


Puddleg said...

The insulin enhancing linoleic acid metabolite could also be an endocannabinoid, they have similar effects to insulin on glucose uptake and fat synthesis.

Peter said...

Yes George, quite likely. From my perspective I have linoleic acid oxidation as central. It signifies, to the whole organism, that calories are about to disappear in to adipocytes/hepatocytes/anywhere else. An early warning. So better eat more NOW. Of course elevated insulin is another necessity for serious calorie sequestration. So if the problem is worse with linoleic acid + elevated insulin, maybe a linoleic acid derivative which has been elongated and desaturated under the influence of insulin might be a better signal to keep on eating. Oh, arachidonic acid! Maybe attach it to a glycerol molecule and..... Munch munch munch.


Passthecream said...

With stimulated Raman spectroscopy you could watch exactly what the deuterium gets up to:'s%20hydrogen,humans)%20is%20safe%20to%20drink.

I wonder how slimming tritium might be?

Peter said...

Yes pass, and also what the lethal dose might be.........


karl said...

"...reagent grade cholesterol was added to both diets (otherwise the model doesn't work to get the essential-for-funding lipid lesions, no sniggering at the back. It's a model)."

Made my coffee come out my nose.. .. 'Grant seeking behaviors' bias research in so many fields - that it really has to be the first question asked when looking at any paper.

So will pharma come out with a weight-loss deuterium drug? They seem pretty good at making risks disappear..

It is interesting that Kendrick's narrative - 'the tear and clot happens first'. If the clot is not easily removed (formed with APO(a)) it gets paved over by new intima and the clot now gets called plaque. This narrative fails to sell cholesterol lowering drugs, but does fit with the observations of nicotine, lead(Pb), high BP, stress, high BG, Lp(a), sickle-cell, etc. etc. etc.

Peter said...

Hahaha karl, sorry-not-sorry about the coffee! There is enormous evolutionary pressure on the "models" themselves.

I love the climate models best for this because tweaking a bit of computer code is a lot easier than developing a new mouse strain containing a mix of knock-outs and knock-ins to get a funding friendly phenotype.

It gets to the point where funding-friendly alarmist climate predictions (yes, they are predictions not possibilities) become an embarrassment even to other climate modellers! Evolutionary pressure in action.

They're hilarious.


Passthecream said...

That DRPUFA paper is a surrealist sketch in terms of the combination of ideas+ingredients which went into it.

I was thinking, deuterium would complicate your concepts relating to protons :))) (2 for the price of 1) which then reminded me that when I search for 'protons 38' on Google I only get strontium but I don't want all those neutrons.

raphi said...

"The sixth and latest IPCC assessment weights climate models according to how well they reproduce other evidence"

what a strange idea to test whether models have any predictive hahahahaha

Unknown said...

An explanation could be found in the weight of the Deuterium. Deuterium probably induces uncoupling because it cannot go through ATP Synthase since it is too big (double the weight of H+) and would destroy the rotating part of the motor therefore disabling the ATP production capability. To avoid that situation, uncoupling would make sense as a safe getaway for mitochondria to resolve that issue.

Peter said...

Pass and Unknown,

Yes, the size of a deuteron may be the same as a proton but the mass might make movement through ATP synthase slow, leading to high delta psi and secondary uncoupling. But the lack of lipid peroxides makes me think this is more of a lipid peroxide reduction effect.

Re blocking ATP synthase, localised injection of oligomycin (in to a rat's knee joint) is *very* inflammatory. I think ROS via high delta psi might be the explanation.

raphi, yes, modelling is now disreputable in my mind. There are also good people out there with good models. But to get government attention you have to be crap and have evolved to outcompete models with simple excellence...


Passthecream said...

If deuterons could be transported into the intermembrane space they might get stuck there unless uncoupling could move them back out.

Eric said...

Off topic, but definitely more about fats than Covid:

See how these are full of carbs and most likely seed oils? This is also what my branch of the family that hails from there still cooks like to day, everything deep fried in sunflower or wheat germ oil. Yet the people in these pictures look slim and healthy (in my family, most do also).

Peter said...

Yes Eric, I too was very skinny as a youth (with a mouthful of cavities and fillings), very slim as a teenager (Hi Peter, you still look like and advertisement for Biafra) and slim through 20s and 30s. I found LC in my 40s. My mum always had a "spare tyre" as she called it and in old images I see my dad was well covered in middle age. Given long enough the young lady's grandmother looks like the eventual phenotype...

Thanks for the access


Eric said...

So did you fill out before switching to LC or was is just your conviction that this was better?

Regarding phenotype, I still haven't quite figured out what kind of nutrition makes for a significant percentage of the US population (by nowhere near all) who are massive and somewhat bloated without being obese. A bloated, meaty face can be part of it. Carbs and seed oils are certainly part of the recipe but there must be something else.

On my recent trip, almost every premade food I looked at contained soybean oil. So maybe it is different seed oils?

raphi said...


I count 2 chubby older women in that NYT piece. Only the young woman seems lean

Peter said...

I developed a small pot belly which I couldn't shift, never obese. Low carb was clearly an unarguably successful solution to weight control and, certainly for me, body composition correction. Bear in mind I was sugar free pretty well all of my life but used seed oils and loads of bread/pasta/rice. I was hard core kayak surfing on all possible occasions, which was a lot each winter. Avoidance of seed oils came later. And I don't worry about defining seed vs non-seed oils, just the number of double bonds.


Peter said...

Adult life re sucrose. I grew up on sucrose until the 80s.


karl said...

@Peter - re: climate-change-cult

I had written about AGW many years ago when a few things popped in to my head that troubled me.

- No one knows the amplitude of the background noise over long time spans - the natural variations. If you don't know this amplitude - what are you measuring?

- They didn't do any error analysis - it blows up in a few months at best.
- Irrigation is a huge confounding variable - historical records do exist for humidity - it has increased - most of the Colorado river that once flowed into the Baja now goes overland as humidity.
- The models don't predict the past and they Don't use the measured emissivity - ends up being estimated - useful as a fudge factor - yet the public thinks this is from first principals and highly predictive.

The need for purpose - the need to virtue signal - has given rise to an amazing cult - and the call is always for more authoritarian interventions.

It puts me in a strange situation - I don't think we should burn up all the worlds petro - better to save it for our descendants to use for better things - there is a better way to generate power. Yet the AWG propaganda has always been obvious garbage masquerading as science. (early on there was an article in Nature where they truncated a graph to change the slope - never retracted.)

But now they are doing the same thing with health care.. and ever more authoritarian interventions -

Passthecream said...

Karl "I don't think we should burn up all the worlds petro - better to save it for our descendants to use for better things - there is a better way to generate power."

By means of fossil energy inputs into agriculture, food preparation, transport, industry, accomodation and so forth people "eat" coal or oil. It sustains us. Massive transformed energy flows like this lead directly to overpopulation and on to epidemic disease, planet heating, planet cooling, ice melting, warfare etc.The superabundance of fossil fuels underpinning the whole human edifice resembles what happens with yeast cells when a source of sugar is suddenly available to them.

Nuclear power has similar consequences. Sunlight and wind power (and tree burning) are finite and self limiting in any given time period but humanity will never willingly live within any limits so the alternative is that those limits be extrinsic and involuntary. Fossil fuels will all be used up; disease will kill us all; the sky will be so polluted that plants can't grow; the planet will somehow become inhospitable to life as we know it; enter your favourite doomsday scenario here.

Peter said...

Pass and karl, yes. You cannot make people out of thin air. It’s like the two rat thought experiment. Put a breeding pair of rats in a massive, pleasant, sanitised cage and supply a kilo of rat food a day. Always a kilo, never more, never less. They’ll breed more rats. At some point they will reach the number of rats which can be supported by a kilogram of rat food. You cannot make more rats than a kilo will support. They don’t spontaneously generate out of nothing. Fertility will drop, elderly rats may not live quite as long as they otherwise might, so the population will stabilise.

The world could never have supported a population of seven billion without a massive [over] supply of food. We are using petrol to make humans. I agree it’s equally possible to turn uranium in to people via the Haber-Bosch process.

If we oversupply our rats with a progressively increasing amount of food to support a population way above that supported by a kilo we will clearly get a huge population, much as the mouse plagues produced in Auss over the last few years have illustrated. We seem to be doing this with humans currently.

The interesting thing about humans is that we don’t over breed indefinitely, provided women are given a choice about it. I’ve read, without ever chasing the verity, that simply educating young girls, especially teaching reading, limits subsequent family size. The developed world doesn’t have enough young tax payers to fund their elderly pension requirements. Educate women, less children, higher proportion of elderly. Hence the UK’s need for young immigrants to get in here and start paying taxes, much as my dad did 70 years ago.

The question is whether educating girls will curb population growth enough in developing countries to limit our world population to something where life is reasonably comfortable the vast majority of us outside the Davos set.

Of course I suppose there are alternatives


cavenewt said...

The last three comments are the most intelligent discussion about overpopulation that I've seen in quite a while. Thank you so much, guys.

I seem to remember that Germany tried disincentivizing reproduction at one point, but then realized they were losing their tax base. Humans are so shortsighted.

Eric said...

Newt, don't know what you remember but I don't think this was ever the case, certainly not in the 20th century (which was full of atrocities).

And now for something completely different:

It is interesting to read the comments. There are many physicians and patients well educated about statin side effects but also many of either sort who wholeheartedly buy into the myth. There's one guy who claims he lowered is LDL from 160s to 70s by switching to a plant based diet. Unless he was living on soy oil and red yeast rice exclusively, I don't believe it.