Tip Epigenetics

[Diane]

Lately I've been finding all kinds of fabulous and distracting reading material having to do with how influenced organisms (including human) still are by environmental incursions. One can only keep room open for the possibility that evolution is at least in part driven by individual adaptations (favourable or unfavourable) as well as species adaptations (the most conventional evolutionary story).

Not much to do with PT, I realize, but as a fundamental scientific mystery which includes human organisms, it involves us as PTs eventually, in that it's humans we are trying to understand scientifically. Right? So we can treat them/ourselves better?

People who eat (all of us, right?) are likely to find at least some little factoid or other in this blogpost interesting. Epigenetics: Feast, Famine, and Fatness

[Diane]

Here's another blogpost: Can holiday stress change your DNA? , courtesy of Precision Nutrition.

(It appears to be a site mostly about marketing a diet/sport plan, but this doesn't mean that their blog is not interesting.)

[Diane]

Somewhat related, from Ken Weiss, (Mermaid's Tale: A conversation about the nature of genetic causation in evolution, development and ecology): Cancer as an 'environmental' disease?

I like that there seems to be an awareness occurring around cellular environment. I've always tried to look at cells as little organisms in their own right. As organisms, cells have ordinary lives. They take in things, make things, metabolize, reproduce (although not many of them have to mate if they are already part of a larger 'organism'), and maybe most importantly, they excrete. Much of what they excrete is used by other cells as raw material for something else, for example, when microglia smell (chemo-sense) trouble, they get busy, come out of stasis, reproduce like crazy, gorge themselves, excrete all sorts of things including something called "nerve growth factor." Nearby neurons either use it to grow stronger or else can be irritated by it (see various glial threads). Small example. Generally cell excretions are at least chemically signalling.

A recent Seed article suggests that multi-cell bodies with all their/our various microbes are more like ecosystems than they/we are organisms.

Small wonder then that we rely so heavily on our neural array to keep up the illusion of separation from environment.

Just some stray thoughts today.

[Diane]

Here is yet another example of encounter between microbe (I think) and human immune system (I think), this time with the microbe genome (I think) winning: Mutant gene lessens devastation of flesh-eating bacteria.

"About the study Musser's lab compared 255 GAS genomes collected from patients in Ontario, Canada, over an 11-year period, to genomes of the 12 strains found in patients with the mutation, a naturally occurring single-nucleotide insertion in the MtsR (metal transporter of streptococcus regulator) gene. Using an integrated systems biology strategy, the study showed that the MtsR mutation results in early termination of the MtsR protein, and that MtsR inactivation is responsible for the decreased necrotizing fasciitis phenotype observed in human patients."

A stray memory from PT school: Sitting in an otherwise forgettable pathology class, with the instructor at the front making us repeat, in unison, "Beta-hemolytic-streptococcus-Lancefield-Group-A!" It worked - I've never forgotten it.

[Diane]

OK, how about that contagious lip cancer rapidly extinguishing Tasmanian devils?
1. Saving Tasmanian Devils From A New Form of Life–Themselves blogpost by Carl Zimmer.
2. Carl Zimmer's news story in NYT on the topic
3. Genetic analysis reveals parasitic origin of contagious cancer devastating Tasmanian devils, from Extinction Countdown, a sciam blog.
4. Nature News: Hopes of a tumour test for Tasmanian devils: Pinpointing nerve-insulating cells as the origin of devil facial cancer could aid diagnosis and vaccination.

Ouch, poor Schwann cells. The TD cancer is trying to evolve itself into a real species in its own right. Nature is so opportunistic that way.

[Diane]

Acute Stress Leaves Epigenetic Marks on the Hippocampus.

So... not sure how to weave this into a new year post.. it was out today, new year's eve, probably only coincidence, so I decided to put it here because of how my own hippocampus tends to forget details if I don't deal with them as I uncover them.. maybe it's a stressed hippocampus, or maybe just forgetful, or the wrong size, or whatever...

Anyway, happy new year.

Regulation of hippocampal H3 histone methylation by acute and chronic stress

Don't let those histones take a toll.

[Diane]

Another story.
Acute Stress Leaves Epigenetic Marks on the Hippocampus

We heard about this years ago - something about hippocampi being half their normal size in soldiers with PTSD.

Maybe I'm getting cynical, but today, I wonder why the sudden effort to broadcast all this - there seems to be something on it every day lately. I suspect public opinion is being shaped for some reason (add a pinch of paranoia to that cynicism). I suppose the next thing to come along will be drugs that one can take prior to a stressful event to prevent the biochemistry of stress and presumably any learning that can result from it or wisdom that can be gleaned from it. Cushioning from the impact of life?
I find myself a bit bothered by visions of nations of unfeeling, non-registering zombies... visions of the Valium-ized women of the 70's, minus all the kidney/liver failure one hopes..

Life IS stress, after all. And when the brain is all used up, or too full of misshapen proteins, or plaque, or scars, or lack of blood flow, or whatever, it dies. And so does the person embedded in it. Is life not about wading in and swimming through it as best one can? And isn't it still true that when there are enough people all stressed about the same thing at the same time, they notice, form groups, move to change things?

Isn't that a good thing? Let oneself be bothered to the point of acting to change input from the physical or social environment? Provided that freedom to do so still is a politically protected right?

[Jon Newman]

Wouldn't that same argument extend to reducing/eliminating pain?

[Diane]

Originally Posted by Jon Newman

Wouldn't that same argument extend to reducing/eliminating pain?

I don't think so. I do not think stress and pain should ever be confused, conflated or otherwise mixed up with one another.

Pain is something produced by the brain, entirely endogenous, a response, and if it persists, maladaptive.

Stress is imposed, almost always, and is the raw material against which the brain develops response, usually favorable, adaptive, growthful.

They intertwine to a degree, in that pain will cause stress.
Stress does not, on the other hand, cause pain, unless the brain can't cope with degree, kind, or relentlessness of a given stress, perhaps.

But they are not the same thing. Not at all.

[Bas Asselbergs]

I see Jon's point though: it is the approach/attitude when dealing with the condition - stress OR pain - they can be similar in the way that they motivate, challenge, and stimulate an effort for change? Although they have different origins, they both serve as triggers for the organism.

[Jon Newman]

Hi Diane,

I wasn't suggesting that pain=stress or the stress causes pain or that the two can be conflated on a neurological level. I was addressing your concerns that systematic observations (science) will allow us, whether it is a good idea or not, to alleviate conditions we find unpleasant such as PTSD or pain or other unmentioned experiences. How do we decide whether an unpleasant human condition is worthy of remediation?

[Diane]

OK, I see what you're saying.

How do we decide whether an unpleasant human condition is worthy of remediation?

Good question. I would start with winnowing out things I do not think such therapies should be based on.
I don't think it should be based on who has access to them because of having more $ to spend.

E.g., a pampered individual stressed over a broken fingernail or a lapdog lost to a coyote, versus one who has been a prisoner for a couple years and subjected to nasty torture, inflicted arbitrarily and randomly.

[Jon Newman]

I think I just wasn't following your post (#7) correctly. You aren't so much against developing the ability to relieve acute stress via drugs but rather advocating for the prudent use of such drugs. Do I have that right?

[Diane]

Originally Posted by Jon Newman

I think I just wasn't following your post (#7) correctly. You aren't so much against developing the ability to relieve acute stress via drugs but rather advocating for the prudent use of such drugs. Do I have that right?

Yes, I'd say so.
"I" (whatever "I" is) find it "stressful" when something "new" such as putative counter-epigenetic drugs, then their application, will become immediately skewed by economics into something quite useless for those in the entire human primate troop who would most benefit because of economic barriers and structural, institutional impediments. Yet my brain always seems to see things that way. My own impatient political brain, expressing itself through its own default mode, finding a thought or a prospect stressful then attempting to relieve its own stress load. AKA "opinion."
Fun person aren't I?

[Jon Newman]

Originally Posted by Diane

Fun person aren't I?

Yes, actually.

[nari]

Aldous Huxley's soma in his Brave New World suggests a sarcastic overboard approach to relieving stress of any variety.
Its implications are ominous but pharma continues to search for the ideal drug/s to keep people happy or at least neutral.

Stress does not = pain, and both are vital for survival. I guess drugs step in when the individual can no longer survive in an acceptable manner. After all, some people thrive on stress; they never relax in the true sense of the word.
They think and act best when stressed and are often quite happy in the process. They are the ones for whom prescription of easy-reach drugs would be unethical; but to some outsiders, comparing them with their own calm selves, they need help.
Probably the persons most at risk are the passive, expressionless 'contented' ones who seem the least stressed. Just an idea....

Nari

[Diane]

Here is yet another tidbit on this topic from Cold Spring Harbor Lab. Proteins, bookmarks, leukemia, etc.

[Diane]

Here is a video on epigenetics, with Shelley Berger. I swear I'm not going out looking for any of these - they are just falling into my computer. This has to be a babyboomer warp in general biological research or something. Find ways to slow down aging etc. Find a market for all of it. Exploit fear of aging/dying? Exploit vanity?

[Diane]

Epigenetics, histones, and mental retardation.

[Diane]

Epigenetics in population separation, into distinct populations with distinct biological differences. Epigenetics of embryological differentiation. Babraham research provides insight into the reprogramming of cell fate.

Sexual reproduction wipes out most of the epigeneisis that occurs - this keeps a species stable over generations, species adaptation happens slowly and through sexual selection/reproduction. But the whole epigenome can be traced and examined, too, because it has to do with individual adaptation within the lifespan of an individual. Then the two can be examined together. Like binocular vision or something - clearer view into genetics as a whole.

[wellbeing]

Diane, I am intrigued the "contagious cancers" links that you posted in post #5 about the Tasmanian devils facing extinction. As an example of both devolution and the malignant significance of epigenetics, what if we played a mental reversal? What if viruses which cannot live outside another organism, actually may represent cases where a cell reverts and then has the random opportunity to spread to another very genetically similar host (member of the same species?)

[Diane]

It's a thought, but to have it be a scientifically acceptable thought, you would need to investigate, then rule out what viruses "are" - i.e., what is already known about them and their behaviour. Don't start up a new theory about something until you understand what's lacking in the old one, what it fails to account for.

[Diane]

Get your red-hot Nature Immuno-Epigenetics papers here, FREE ACCESS !!! until April 2010 ----> LINK

I think we ought to have at least a passing familiarity with this, given that our nervous system tries to control the immune system as best it can, and is forced to live with the consequences of whatever adventures it has and fights it gets into. Sometimes its own organism is attacked for whatever reason. I feel for the nervous system in those circumstances, like I do for any battered spouse, this one without hope of escape til death really does part.

[Diane]

Why your DNA isn't your destiny, from Time. Very interesting 4 pager about all sorts of impacts on successive generations of humans (and other creatures) because of environmental epigenetic influences. It's making evolutionists remember Lamarck.

[smith]

Lamarck's ideas can account for some within species varitation (arctic hare changing fur colors with the seasons), but not speciation. Darwin better explains speciation I believe. Change through descent. If I can remember correctly.

[Jon Newman]

Originally Posted by Diane

Why your DNA isn't your destiny, from Time. Very interesting 4 pager about all sorts of impacts on successive generations of humans (and other creatures) because of environmental epigenetic influences. It's making evolutionists remember Lamarck.

Also make note of The Baldwin Effect (no,not those Baldwins).

Smith, I actually thought "change through dissent" (from another thread) was pretty inciteful and wasn't sure if it was intentional or a typo.

[Diane]

Nice video on epigenetics, #7 in this set of prize-winning posters and videos. A video on Alzheimer's at #10.

[Diane]

Teasing Out the Effects of Environment on the Brain by Mo Costandi.

The Switches That Can Turn Mental Illness On and Off by Carl Zimmer.

Mo says Carl pretty much says what he says. So, I guess that means, take your pick.

[Jon Newman]

Part 1 follows. You can access the remaining parts by going to youtube directly.

(hat tip: Imaginary Foundation)

[Diane]

Epigenetics and the human brain. Excerpts:
1.

Several aspects of epigenetic marks are of particular interest to researchers: (1) they are gene specific, (2) they are influenced by the environment, (3) they are dynamic and reversible, but (4) they can nonetheless remain stable across generations.

2.

epigenetics is the ensemble of processes that link a person’s genotype, or the genetic information, to its phenotype, the physical and biological expression of this genetic information. These processes regulate gene activity. They can activate or inactivate genes, alter the amount of protein synthesized or expressed by a gene, and determine when a gene is expressed throughout the course of a lifetime. By implementing such changes, epigenetic processes regulate gene activity in a dynamic way.

3.

several enzymes that modify DNA or histone proteins are essential elements of signaling pathways, allowing proper neuronal signaling for learning and memory.9 This is because the formation of long-term memory requires that epigenetic processes induce lasting changes in gene expression in brain cells. Mice with dysfunctions in any of the epigenetic components that contribute to these changes can have impaired long-term memory.10,11

[Diane]

A new paper, mentioned in this report, Epigenetic 'memory' key to nature versus nurture, published in Nature.

Excerpt:

"There are quite a few examples that we now know of where the activity of genes can be affected in the long term by environmental factors. And in some cases the environment of an individual can actually affect the biology or physiology of their offspring but there is no change to the genome sequence."

[Diane]

Lamarck's Revenge

Very good review of a book called Epigenetics: The Ultimate Mystery of Inheritance, by Richard Francis, also the author of 'Why Men Won't Ask for Directions'.

[Randy Dixon]

I'm just cruising through here quickly and didn't have time to read any of the articles but you probably have read about the domestication of silver foxes and how domestication changed some of their phenotypical expression. Is this the same thing you are discussing?

I would suggest googling Silver Foxes but you might end up with a senior citizen porn site.

[Diane]

Sounds like it would be in the same ball park.

[JayCola]

Our Genes Our Destiny?

A "hidden" code linked to the DNA of plants allows them to develop and pass down new biological traits far more rapidly than previously thought, according to the findings of a groundbreaking study by researchers at the Salk Institute for Biological Studies.

[Diane]

Podcast from SciAm about epigenetics, Nov 22/11

[Diane]

This looks good, from National Geographic, on twin studies and epigenetics.

[amacs]

some more material relevant to pain

regards

ANdy

[Diane]

Epigenetics and osteoarthritis link.

[Tirving]

Originally Posted by amacs

some more material relevant to pain

regards

ANdy

Pain, having influence on genetic expression and having epigenetic properties is an extremely interesting topic (and, it would seem, relevant to this forum). Thanks for posting this and for posting the OA/epigenetics article Dianne.

[AdamB]

Thank you very much for this thread!

[AlexP]

Watched this today, it was all new to me and very interesting. No surprise a relevant thread already exists!

http://www.voicesfromoxford.org/vide...ry-biology/184