Heavy drinking will literally rot your DNA

Heavy drinking will literally rot your DNA
Even occasional heavy drinking can have long-lasting impacts
National Monitor
Ian Lang
January 02, 2014

For some, college wouldn’t be worth attending were it not for the weekend alcohol benders: Week-long bouts of studiousness bookended by weekends of debauchery and heavy drinking. Provided you lay off the sauce more often than not, letting loose a couple of days per week never hurt anyone, right? Wrong. According to a new study, even sporadic instances of heavy drinking can damage DNA.

Coming out of Mexico, the study worked with university students to analyze the effect of weekend alcohol consumption on the lipids comprising cell membrane and its genetic material, i.e. DNA. This is the first study of its kind to examine the effect of alcohol on DNA during the early stages of alcohol abuse. Earlier studies ignored it, likely because they focused on subjects who had consumed alcohol in an addictive manner for some time.

Oddly enough, researcher Adela Rendón was prompted to launch the study when she observed college students acting like college students. While lecturing Clinical Biochemistry on a Monday morning, she noticed that students who had drank over the weekend were inattentive and out of sorts. She suspected that this was due to alcohol consumption and not because “Clinical Biochemistry” sounds like the most boring subject on Earth. She involved the students and went ahead with gathering experts and completing necessary administrative documents.

The eventual aim of the study? Oxidative damage caused by the consumption of alcohol beverages in young people.

The activity of the alcohol enzyme dehydrogenase, responsible for metabolizing ethanol into acetaldehyde, acetoacetate and acetone was measured. Oxidative damage is evaluated by a TBARS biochemical test (types that react to barbituric acid), and reflects the lipid peroxidation that affects the membrane due to the impact not only of the ethanol in the blood but also of the acetaldehyde produced by the action of the enzyme on the ethanol. That means there are at least two means by which free radicals are formed and which can damage cell membrane integrity.

Researchers were surprised not because they found results, but by the volume of those results.

“We saw that the ones who drank sustained twice as much oxidative damage compared with the group that did not consume alcohol,” Rendón said. Further examining cells via the “comet test” (used to measure damage to cell DNA), they found that students who drank had 5.3 times the number of damaged cells as those who abstained.

Scientists expect to observe that kind of damage in chronic alcohol abusers, but were surprised to see any damage at all stemming from a comparatively isolated instance of drinking.

“When we talk about youth alcohol abuse, we are referring to youngsters who drink alcohol without having become addicted. Addiction involves a more complex issue socially and psychologically speaking. This is social alcohol abuse,” said Rendón, “but which causes damage in the long term and you have to be aware of that.”

The harmful consumption of alcoholic beverages is a global issue and constitutes a significant health, social and economic problem. According to World Health Organisation data, alcohol is responsible for 2.5 million deaths a year worldwide and drinkers between the ages of 19 and 25 account for 320,000 of them...

Many of us have more than one genome, either from mutations--or from people with whom we shared a womb

This is amazing. We don't have any way to know it, short of multiple DNA and/or blood tests, but many of us might actually be fused twins!

DNA Double Take
Noah Berger
New York Times
September 16, 2013

From biology class to “C.S.I.,” we are told again and again that our genome is at the heart of our identity. Read the sequences in the chromosomes of a single cell, and learn everything about a person’s genetic information — or, as 23andme, a prominent genetic testing company, says on its Web site, “The more you know about your DNA, the more you know about yourself.”

But scientists are discovering that — to a surprising degree — we contain genetic multitudes. Not long ago, researchers had thought it was rare for the cells in a single healthy person to differ genetically in a significant way. But scientists are finding that it’s quite common for an individual to have multiple genomes. Some people, for example, have groups of cells with mutations that are not found in the rest of the body. Some have genomes that came from other people.

“There have been whispers in the matrix about this for years, even decades, but only in a very hypothetical sense,” said Alexander Urban, a geneticist at Stanford University. Even three years ago, suggesting that there was widespread genetic variation in a single body would have been met with skepticism, he said. “You would have just run against the wall.” ...

In 1953... a British woman donated a pint of blood. It turned out that some of her blood was Type O and some was Type A. The scientists who studied her concluded that she had acquired some of her blood from her twin brother in the womb, including his genomes in his blood cells.

Chimerism, as such conditions came to be known, seemed for many years to be a rarity. But “it can be commoner than we realized,” said Dr. Linda Randolph, a pediatrician at Children’s Hospital in Los Angeles who is an author of a review of chimerism published in The American Journal of Medical Genetics in July.

Twins can end up with a mixed supply of blood when they get nutrients in the womb through the same set of blood vessels. In other cases, two fertilized eggs may fuse together. These so-called embryonic chimeras may go through life blissfully unaware of their origins.

One woman discovered she was a chimera as late as age 52. In need of a kidney transplant, she was tested so that she might find a match. The results indicated that she was not the mother of two of her three biological children. It turned out that she had originated from two genomes. One genome gave rise to her blood and some of her eggs; other eggs carried a separate genome.

Women can also gain genomes from their children. After a baby is born, it may leave some fetal cells behind in its mother’s body, where they can travel to different organs and be absorbed into those tissues. “It’s pretty likely that any woman who has been pregnant is a chimera,” Dr. Randolph said.

Everywhere You Look

As scientists begin to search for chimeras systematically — rather than waiting for them to turn up in puzzling medical tests — they’re finding them in a remarkably high fraction of people. In 2012, Canadian scientists performed autopsies on the brains of 59 women. They found neurons with Y chromosomes in 63 percent of them. The neurons likely developed from cells originating in their sons.

In The International Journal of Cancer in August, Eugen Dhimolea of the Dana-Farber Cancer Institute in Boston and colleagues reported that male cells can also infiltrate breast tissue. When they looked for Y chromosomes in samples of breast tissue, they found it in 56 percent of the women they investigated.

Exercise Alters DNA within minutes

How Exercise Can Change Your DNA
By Alice Park
Time
March 07, 2012

Just 20 Minutes of Exercise Can Change Your Genes MyHealthNewsDaily

Exercise does a lot of good things — it burns calories, helps keep your weight in check and lowers your risk of heart disease, stroke and diabetes. Now add one more thing to the list: physical activity can change your DNA.

Unlike the aberrations and genetic mutations caused by carcinogens and toxins, exercise-induced alterations to DNA are more like tune-ups, helping muscles to work better and more efficiently. What’s more, these changes occur even after a single 20-minute workout.

Juleen Zierath, a professor of physiology at the Karolinska Institute in Stockholm, reports with her colleagues in the journal Cell Metabolism about these very early changes that muscle cells undergo the first time you get off the couch and into the gym. The researchers worked with a group of 14 young men and women who were relatively sedentary, and asked them to work out on an exercise bike that measured their maximum activity levels. The participants also volunteered to give up a little bit of muscle, from their quadriceps, in a relatively painless biopsy procedure performed under local anesthesia. The researchers took the biopsy of muscle cells once before the participants exercised, and again within 20 minutes afterward.

VIDEO: Walking While Working: Healthland’s Belinda Luscombe Tries the Treadmill Desk

Using the biopsied samples, researchers compared the activity in a series of muscle-related genes before and after exercise. More genes were turned on in the cells taken after the exercise and the participants’ DNA showed less methylation, a molecular process in which chemicals called methyl groups settle on the DNA and limit the cell’s ability to access, or switch on, certain genes. By controlling how much methylation goes on in certain cells at specific times, the body regulates which genes in the DNA are activated — that’s what differentiates the development of an an eye cell, for example, from that of a liver cell.

Methylation also helps to prime muscle cells for a bout of exercise, getting them to pump out the right enzymes and nutrients the muscle needs to get energy and burn calories while you’re pounding the pavement during that mile-long jog. “We are trying to get at the early messages that the muscle is [receiving in order] to say, ‘Something is happening here, we need to coordinate so we can get more enzymes and more machinery on board so we can cope with the demands of this exercise,’” says Zierath.

The more intense the exercise, she says, the more the methyl groups are on the move. She and her team were able to see this firsthand by comparing gene activity in participants who also agreed to exercise at two different intensities over a period of a week. On one visit, they were asked to cycle until they reached 40% of their maximum capacity; on another occasion, they biked until they reached 80% of their maximum. The muscle biopsies following the 80% sessions showed a lower concentration of methyl groups — and therefore more RNA, which is the first byproduct of gene activity — than samples taken after the 40% sessions.

MORE: Why Exercise Won’t Make You Thin

To confirm the role of exercise on gene expression in muscle, the scientists then studied how calcium affected the entire system. When muscle cells start to gear up for intense activity like exercise, they release calcium, which fuels the contraction process. When the scientists blocked calcium production, the effect disappeared, and the muscles didn’t contract as much.

That’s when Zierath threw in some coffee — or more specifically, caffeine. Caffeine triggers the release of calcium, and can enhance the way methyl groups move aside to turn on the genes that help muscles contract. When she added caffeine to a lab dish containing cells from the leg muscles of rats, the muscle cells showed lower concentrations of methyl groups and more mRNA — a similar effect as seen after exercise — as she expected.

But, says Zierath, that doesn’t mean you can skip the workout for a cup of coffee instead. “Most of the physiological effect of the caffeine we drink is on the central nervous system, and not dispersed to all the muscles,” she says. “In order to get the same kind of effect we saw in the cells, you would have to drink 50 cups of coffee a day, which is close to the lethal dose. In my mind, half an hour of moderately high intensity exercise is sufficient to do the same thing.”

Read more: http://healthland.time.com/2012/03/07/how-exercise-can-change-your-dna/#ixzz2UXQNygP3