Wednesday, April 09, 2014

Dr Doug Wallace on mitochondria

This link came to me from Bill Lagakos via Facebook. It covers a lot of ground and is, unavoidably, a little superficial in places when the subject matter is very deep. He mentions his work with mice made heteroplasmic for two different strains of mitochondria, the NZB and the 129. Both work perfectly well as the sole mitochondrial population giving normal mice. Engineering heteroplasmy produces mice with a stack of problems in high energy demand tissues.

I got to this point, about half way through the presentation, before the penny dropped that the speaker was Doug Wallace, group leader of the people who published this paper

There is a more detailed analysis of this aspect in Nick Lane’s comment in the same edition of Cell about why heteroplasmy might be a Bad Thing, especially in high ATP demanding cells.

I spent much of the presentation thinking that there was no mention of nutritional tools for managing mitochondrial heteroplasmy and very little about mitochondrial mutations and ageing but these came up in the Q and As at the end. The nicest question was about intermittent fasting but Wallace immediately threw in a ketogenic diet as a potential technique for clearing out deleterious heteroplasmic mitochondrial sub populations. He also mentioned the ubiquity of low level heteroplasmy and pre ovulatory selection for optimal mitochondrial population in oocytes...

A lot of ground. Much there which makes sense.


Thursday, March 06, 2014

Would you like soya oil poured over your methionine spiked casein?

Having a great week off work with my daughter, mostly swimming and gardening, so that blogging is off the radar as I'm fairly much off line at the moment. But...

I guess everyone has seen the takedowns of "meat causes cancer" by Longo et al. so no need for me to chime in. One hundred percent guilty of issuing a press release suggesting causation from an observational study. Duh. Hysterical highlight that meat is cancer for the decade 55-65 years of age and then, come your pension (as a bloke), it becomes the elixir of life. Shrug.

In the same Aussie pile of wallanga pertaining to report science there was a slightly more interesting study published by Le Couteur et al using the standard crippled C57BL/6 mouse strain. They fed umpteen macronutrient ratios to umpteen mice and looked at the longevity. Remember, you cannot feed butter to C57BL/6 mice. Saturated fats break their brain, they have problems with their peroxisomes and with their first phase insulin response, so they in no way resemble any but the most unfortunate of human beings. Feeding them saturated fat is out unless you feed them a ketogenic diet. With that said, enjoy the last comment in this quote from the group:

"Although the mice on a high-protein diet ate less and were slimmer, they also had a reduced lifespan and poor heart and overall health.

Those on a high-carbohydrate, low-protein diet ate more and got fat, but lived longest.

The mice that ate a high-fat, low-protein diet died quickest".

Executive summary: Fat = death.

A brief trip to supplementary data gives what the diets were made of:

"Diets varied in content of P (casein and methionine), C (sucrose, wheatstarch and dextrinized cornstarch) and F (soya bean oil)".

The only fat used was soya bean oil. Can I emphasise again, as many times before:


A free "did you notice that?" snippet: Protein was "casein and methionine". Methionine restriction has been shown to prevent metabolic syndrome and possibly to extend lifespan. If you wanted to show protein was bad, might you spike casein by adding extra methionine? To complement the PUFA induced fat-badness??? How do these people sleep at night?


Sunday, February 16, 2014

Protons (35) TFAM-KO revisited

Those adipose tissue TFAM knockout mice need a revisit. They have an engineered, adipose tissue specific, catastrophic injury to complex I. Complex I failure = insulin-independent DNL, so they should be fat. But they are thin, euglycaemic and have excellent glucose tolerance on a GTT. If complex I failure gives obesity, what is going on here?

These mice were one of the core triggers to me for the concept of TCA halting due to the inability of an injured complex I to oxidise NADH. It's very clear that rotenone, at concentrations which inhibit complex I without killing your model, activates de novo lipogenesis as a technique to deal with excess NADH, excess acetyl-CoA and to provide long chain saturated fatty acids to input as FADH2 to the ETC (at ETFdh) and so to run the rest of the ETC downstream of complex I.

Look at the ability of TFAM adipocytes to uptake 2-deoxyglucose with and without insulin. This is what you get:

TFAM mouse adipocytes appear to be VERY insulin sensitive. In fact they can uptake glucose in the complete absence of any insulin, at the same rate that control (Lox) adipocytes can under supra maximal* insulin. They are insulin hypersensitive without needing any insulin...

*In the supplementary methods these adipocytes are treated with 1.25iu/kg to get this graph, but they are in cell suspension after removal and predigestion, so I don't quite see what concentration of insulin was used. I think is a reasonable assumption that the concentration would be supra maximal...

Yet these adipocytes have mitochondria with a delta psi which is profoundly depressed. The photomicrographs show them as being completely f*cked. So enhanced insulin sensitivity is completely counterintuitive.

What do they do with the glucose they so readily take up? They convert it in to lipid (supplementary data Fig2):

*primary isolated adipocytes, real functional cells, supplied with 5mmol/l glucose.

This lipogenesis looks remarkably like the lipogenesis you see in tissue culture cells treated with rotenone (aside; or in post-obese humans during an OGTT). These cells are energy deprived through the inability to utilise NADH. They side step this by converting acetyl-CoA to lipid and then oxidise this lipid through beta oxidation, which is less dependent on the TCA. The cells appear to be insulin sensitive because they are starving. Even without insulin there is a huge glucose uptake. Once given a few GLUT4s by supplying insulin you get supra-huge glucose uptake. I have to wonder if this is simply a concentration gradient effect, hard to say from the paper. The actual number of GLUT4s (up or down in number cf controls) is completely model dependent, if you read around. But the glucose gets converted to lipid. When you look at ATP turnover you see starvation:

*Note, cell culture 3T3-L1 derivatives at 25mmol/l glucose.

Careful here, we have gone from real mice with TFAM KO adipocytes to TFAM suppressed cell lines. Cultured shTf1 have mild knockdown, shTf2 have severe. These are tissue culture cells. They may or may not behave in quite the same manner as cells from a real live slightly broken mouse...

But the message appears to be that the processes to extract energy from glucose need to be up-regulated to the maximum possible.

Back to real broken mice. Their adipocyte mitochondria are uncoupled (i.e. they fail to correctly increase delta psi when ATP-synthase is blocked by oligomycin) and have an elevated oxygen consumption rate when running on succinate (to bypass complex I)

The uncoupling is very interesting. My feeling is that these cells really are uncoupled, really are insulin resistant due to this and that whatever effect insulin has at high doses is taken advantage of, to the maximum amount possible. Hence the term "apparently" insulin sensitive, when actually insulin resistant...

You could suggest that the underlying insulin resistance is reflected in the glycerol release. These cells, which do insulin-independent glucose uptake, also release glycerol in larger amounts than controls. Oh, and look at the palmitate oxidation too:

The FFAs released from their glycerol backbone do not appear to be discharged in to the systemic circulation (in these mice), they get oxidised because the adipocytes are in ATP starvation and can still use ETFdh to generate some ATP. We have considered FFAs and uncoupling before. The ATP situation may not suggest uncoupling as a particularly good idea but FFAs are FFAs and, if insulin is silenced, then uncoupling seems unavoidable.

BTW the control of uncoupling is so fascinating we'll have to come back to it some other time. Needless to say it integrates ADP, ATP, CoQ redox status, cytoplasm:mitochonrial ATP ratio. And free fatty acid availability, of course.

So let's summarise: Complex I damaged adipocytes are greedy for glucose without (or with) insulin. They are concurrently insulin resistant, which limits their ability to store triglycerides. Their size is immaterial. I was driven to this by a paper which demonstrated that adipocytes isolated from sucrose/lard fed mice are all equally insulin resistant, irrespective of their size (what exactly determines basal lipolysis in an interesting question, I'd guess it is not simply size, though it must be related. It's probably very important). Obviously isolated adipocytes are clear of the influence of leptin, the ventromedial hypothalamus and the sympathetic nervous system, which will certainly not be the case in any intact mouse. But, at the level of very core metabolism, this makes sense in the light of macroscopic observations. When adipocytes STOP getting fatter they do so because complex I has broken to an adequate degree. As they cease to enlarge and cease to respond to insulin they release FFAs, without any concern for higher level metabolic signalling from insulin. Systemic elevated FFAs uncouple the rest of the body's mitochondria (outside the CNS) and on we go through IGT to diabetes.


Monday, February 03, 2014

Dr Ravnskov on statins for primary prevention of CVD

This is more of a Facebook link than a blog post, but hats off to the BMJ as they have recently published some excellent articles in which neat truth appears to be very controversial (if you pedal b*ll*cks for a living).

Now they have published Dr Ravnskov's response to Ebrahim's pro statin for primary prevention paper. It's a nice reply and it's great to see a medical journal giving a voice to sanity. Of course, hats off to Dr R for being that voice.

You can read the letter here.


Friday, January 31, 2014

TV Pantomine or the Oxford study

I don't ever watch television (we have no digital decoding box, the TV is for DVDs) and I can't waste the time to watch this performance on the internet.

There are two truisms I love.

First: How can you tell when a politician is lying? You see their lips move.

Equally good: Any semblance of television documentaries to real life is purely accidental.

For a lesson in how to stack a real study against low carb this Oxford group beats any television entertainment hands down. Also, if you ignore the crap from the researchers, there are lots of interesting (pro LC) data in this study, especially the myocardial energetics and body composition.

What they found, and which made the tittle of the paper, was the gem that LCHF eating "impairs cardiac high-energy phosphate metabolism". Baaaad?

What I really liked was that despite "9% lower cardiac PCr/ATP (P< 0.01)" there was "no change in cardiac function".

Ketones. Ketones allow normal cardiac function at reduced PCr/ATP levels. Ketones (from Veech's work) bypass insulin resistance, be that pathological as in Alzheimers or physiological as in very LCHF eating. Cardiac muscle functions well at reduced ATP levels, provided ketones are available.

Feeling like crap in the early stages of ketosis (Atkins Flu™) is common, it's usually at its absolute worst at about a week in to ketogenic eating. This group clearly knew how to time their cognitive testing! They have more of an agenda than I do.

Both the study and the TV drama have the potential to injure people who need ketogenic eating, I guess the TV show more so than the Oxford study, because it is more likely to stop grass roots level defections from Weight Watchers to genuinely healthy fat-based eating.


Saturday, January 25, 2014

An aside on psychiatric links from Sid Dishes

Sid has recently put these two excellent links up on her Facebook timeline. The Protons thread is slowly working its way towards probable causes of complex I failure and an awful lot of the basic mitochondrial information comes from papers on Parkinsons disease or Alzheimers disease.

It has been clear for some time that many, many mitochondrial problems, when localised in specific sets of neurons, are categorised as psychiatric illnesses without needing to have a full blown genetic mitochondrial disease at their core. Acquired mitochondrial dysfunction, most likely at complex I, might well be all you need. Have the right SNPs in genes for proteins of the ETC or assorted ion channels might allow you to be allocated schizophrenia, bipolar disorder or major depression as your pigeonhole.

Trying to treating mitochondrial psychosis by tinkering with the superficial knock on effects at the neurotransmitter level will be of limited effectiveness. Altering bioenergetics using an NAD+ precursor or by inducing ketosis might be far more logical approaches.


The psychiatric presentation of mitochondrial disorders in adults

Nicotinamide, NAD(P)(H), and Methyl-Group Homeostasis Evolved and Became a Determinant of Ageing Diseases: Hypotheses and Lessons from Pellagra.

The second paper is a rather broad brushed picture of evolution, society and NADH. Gross NAD deficiency with adequate calories (pellagra) will mean that there is almost no time for NAD+ to exist before being reconverted to NADH. The high NADH/NAD+ ratio will particularly favour excess superoxide generation at complex I if there is any reverse electron flow from the CoQ couple. It's a pity this paper does't have mtG3Pdh in its diagram of the ETC. An interesting read even if it's full of concepts which the Hyperlipid perspective might question or might invert the causality there-of.

EDIT: I found this one myself and nearly lost it. The perils of PubMed-ing in your lunch break at work and not emailing the link to yourself!

Neuroanatomical Pattern of Mitochondrial Complex I Pathology Varies between Schizophrenia, Bipolar Disorder and Major Depression



Thursday, January 23, 2014

Macrobiosis, macrobiopathy?

I hope we all remember Barnad's low fat vegan treatment for diabetes. This figure sums it up:

By 74 weeks folks are not looking very well controlled. Certainly not compared to sustained LCHF. Now, if we crop it nicely we get:

Which makes low fat veganism look pretty good, just so long as you limit your study to 12 weeks.

How a bout a macrobiotic diet?

Very low fat, low protein, LOADS of fibre and complex grain based carbs.

Take some diabetics, measure some numbers, feed for three weeks by skilled macrobiotic cooks while teaching macrobiotic cookery, re test at twelve weeks after self preparing food at home for the last nine of those weeks.


We don't get HbA1cs in this study but we have the fasting glucose levels, the 2h post prandial levels, the lipid levels and I quite like the blood pressure levels.

Everything improved when you have a real macrobiotic cook serving you. Do it yourself and by twelve weeks things are already starting to fall to pieces:

Two hour post prandial glucose levels are already rising by 3 months. Even Barnard's study preserved glycaemia for longer than this. You might expect triglycerides to be rising too. They are. If you could give a monkeys about cholesterol levels they too are deteriorating:

Blood pressures pre intervention 127/76, 3 weeks 113/69, 12 weeks, ohoh, 118/75.

Of course you could always claim that these folks weren't doing the macrobiotic diet correctly at home.

Me, I think they are metabolically broken and, even before they stop losing weight, they show their broken metabolism by their climbing post prandial (and fasting) glycaemia. By 74 weeks they will be worse off than Barnards failures.

There is no answer for diabetics other than LCHF.

Sometimes things come up in comments which are so good. As Johnny so kindly obliged the person who linked to the macrobiotic study in their request for comments:

"Yes I would like to comment. Please put your keyboard into a potato sack and throw it into the sewer"



BTW, if anyone can reconcile Fig 1 and the red line in Fig 2, congratulations!