Posts by Comatose

The essence of this finding is a series of molecular events that enable communication inside cells between the nucleus and mitochondria. As communication breaks down, aging accelerates. By administering a molecule naturally produced by the human body, scientists restored the communication network in older mice. Subsequent tissue samples showed key biological hallmarks that were comparable to those of much younger animals.

"The aging process we discovered is like a married couple -- when they are young, they communicate well, but over time, living in close quarters for many years, communication breaks down," said Harvard Medical School Professor of Genetics David Sinclair, senior author on the study. "And just like with a couple, restoring communication solved the problem."

This study was a joint project between Harvard Medical School, the National Institute on Aging, and the University of New South Wales, Sydney, Australia, where Sinclair also holds a position.

The findings are published Dec. 19 in Cell.

Communication breakdown

Mitochondria are often referred to as the cell's "powerhouse," generating chemical energy to carry out essential biological functions. These self-contained organelles, which live inside our cells and house their own small genomes, have long been identified as key biological players in aging. As they become increasingly dysfunctional over time, many age-related conditions such as Alzheimer's disease and diabetes gradually set in.

Researchers have generally been skeptical of the idea that aging can be reversed, due mainly to the prevailing theory that age-related ills are the result of mutations in mitochondrial DNA -- and mutations cannot be reversed.

Sinclair and his group have been studying the fundamental science of aging -- which is broadly defined as the gradual decline in function with time -- for many years, primarily focusing on a group of genes called sirtuins. Previous studies from his lab showed that one of these genes, SIRT1, was activated by the compound resveratrol, which is found in grapes, red wine and certain nuts.

Ana Gomes, a postdoctoral scientist in the Sinclair lab, had been studying mice in which this SIRT1 gene had been removed. While they accurately predicted that these mice would show signs of aging, including mitochondrial dysfunction, the researchers were surprised to find that most mitochondrial proteins coming from the cell's nucleus were at normal levels; only those encoded by the mitochondrial genome were reduced.

"This was at odds with what the literature suggested," said Gomes.

As Gomes and her colleagues investigated potential causes for this, they discovered an intricate cascade of events that begins with a chemical called NAD and concludes with a key molecule that shuttles information and coordinates activities between the cell's nuclear genome and the mitochondrial genome. Cells stay healthy as long as coordination between the genomes remains fluid. SIRT1's role is intermediary, akin to a security guard; it assures that a meddlesome molecule called HIF-1 does not interfere with communication.

For reasons still unclear, as we age, levels of the initial chemical NAD decline. Without sufficient NAD, SIRT1 loses its ability to keep tabs on HIF-1. Levels of HIF-1 escalate and begin wreaking havoc on the otherwise smooth cross-genome communication. Over time, the research team found, this loss of communication reduces the cell's ability to make energy, and signs of aging and disease become apparent.

"This particular component of the aging process had never before been described," said Gomes.

While the breakdown of this process causes a rapid decline in mitochondrial function, other signs of aging take longer to occur. Gomes found that by administering an endogenous compound that cells transform into NAD, she could repair the broken network and rapidly restore communication and mitochondrial function. If the compound was given early enough -- prior to excessive mutation accumulation -- within days, some aspects of the aging process could be reversed.

Cancer connection

Examining muscle from two-year-old mice that had been given the NAD-producing compound for just one week, the researchers looked for indicators of insulin resistance, inflammation and muscle wasting. In all three instances, tissue from the mice resembled that of six-month-old mice. In human years, this would be like a 60-year-old converting to a 20-year-old in these specific areas.

One particularly important aspect of this finding involves HIF-1. More than just an intrusive molecule that foils communication, HIF-1 normally switches on when the body is deprived of oxygen. Otherwise, it remains silent. Cancer, however, is known to activate and hijack HIF-1. Researchers have been investigating the precise role HIF-1 plays in cancer growth.

"It's certainly significant to find that a molecule that switches on in many cancers also switches on during aging," said Gomes. "We're starting to see now that the physiology of cancer is in certain ways similar to the physiology of aging. Perhaps this can explain why the greatest risk of cancer is age. "

"There's clearly much more work to be done here, but if these results stand, then many aspects of aging may be reversible if caught early," said Sinclair.

The researchers are now looking at the longer-term outcomes of the NAD-producing compound in mice and how it affects the mouse as a whole. They are also exploring whether the compound can be used to safely treat rare mitochondrial diseases or more common diseases such as Type 1 and Type 2 diabetes. Longer term, Sinclair plans to test if the compound will give mice a healthier, longer life.

30

You put your right foot in...you put your left foot out...

by hokeypokey in

enjoying the commentary on this board and up at night doing some research.

coming to grips with my new reality.

- hokey pokey.

Comatose

Hi! Welcome. I hope to learn more about your story in the future. Glad to have you.

112

Why does Organic Chemistry prove God's exists?

by KateWild in

so bring it on, and lay the evidence on me, kate (but perhaps you should start a new thread).-adam.

it does not prove god exists, there is no substantial evidence god is real.

if one is a self labeled atheist, one has no desire to see gods fingerprints in organic chemistry.

Comatose

This was crazy. Your thread title seems as if you will answer the question, then you say straight off that it doesn't prove it. lol

I agree it doesn't and that you have the right to believe what you choose. So....... Have a great rest of the day! :)

2

Do you Haiku?

by Comatose in

jw
friends

dad.

all these unsaid words.

caught in the air between us.

Comatose

Dad

All these unsaid words
Caught in the air between us
Sadness and silence

78

I think Im an Atheist :(? :)?

by chrisuk in

jw
friends

ive been pondering my beliefs for a while now and ive come across things that i just cant accept.

i was recently walking with a christian who stated that the universe couldnt just come from nothing.

he said that the universe was so complex that it needed a designer, he also said something which ive heard before.

Comatose

This train has jumped the track and is heading for the cliff.

25

dannalight - newbie wants to say hi

by besty in

jw
friends

say hi to dannalight here.... she made a post http://www.jehovahs-witness.net/jw/friends/46/12/welcome#4909211 but it made more sense to make a new topic for her....

Comatose

Hi and welcome! It's really nice to have you. I look forward to getting to know you.

78

I think Im an Atheist :(? :)?

by chrisuk in

jw
friends

ive been pondering my beliefs for a while now and ive come across things that i just cant accept.

i was recently walking with a christian who stated that the universe couldnt just come from nothing.

he said that the universe was so complex that it needed a designer, he also said something which ive heard before.

Comatose

I know how you feel Chris. I've been there and in some ways still go there from time to time. The grieving does stop though for the most part. And life means more to me now. Life is so much more precious than it was. Living and mattering to others is now so important.

I have also thought about all your questions you raise. I've had the same revelations. You are well on your way to healing. Hang in there.

81

Do you frown upon tattoos?

by confusedandalone in

i am very interested in hearing from people who really think that people with tattoos are somehow weird or cagey individuals.

i would just like to get your outlook on this matter.

today i was in a grocery store and i sawe this guy with his two kids and his wife shopping.

Comatose

I got one as I left WT. I'm very glad I did. It's very personal for me. Looks great.

57

oh dear I think I messed up and pushed too hard

by Frazzled UBM in

reading all the posts on the wt study on higher education and careers really fired me up yesterday.

i have 2 undergraduate and 2 postgraduate degerees and a career as a result which allows me to provide well for my jw wife and son.

i was already unhappy because after 5 or 6 weeks of not going and appearing to be making progress she went back on sunday for the second sunday in a row and as usual was away all day.

Comatose

So sorry you are going through this. Speak to a lawyer. Keep tabs on her correspondences if you can. You don't want her running off with your kid.