I have neglected my scienceblogging duties for too long, so here is a compendium of the latest and coolest news to cross my desk.
* Resveratrol, a compound found in red wine and a long-time favorite of the blog, helps keep you fit by tricking the liver into thinking that you’re fasting (subscription wall). Focusing on the resveratrol target Sirtuin 1 rather than the drug itself, a team found that fasting stimulates the liver to break down fat and cholesterol via a signal from SIRT1. This further supports the idea that the drug lengthens lifespan among a staggering number of other beneficial effects largely by “tricking” the body into acting as though it’s starving.
* Move over resveratrol! Reporting in Cell, researchers have created a mouse that lives longer, eats more, weighs less and resists the negative physical effects of stress by knocking out a brain-specific signaling molecule called type 5 adenylyl cyclase (AC5; subscription wall). If AC5 proves as easy to manipulate with drugs as SIRT1 this news could be huge for people with stress-related heart and weight problems. Which is to say quite a lot of us.
* More good news – caffeine and exercise helps a mouse lose weight! You probably knew that already. Did you know that it also protects against cancer? The researchers specifically looked at skin cancer from ultraviolet light, but I will go out on a limb and predict that a limited number of other types of cancer will also prove amenable to the jogging-and-coffee treatment. I’ll explain my reasoning after the jump.
* A new population genetics study proposes a genetic theory of autism.
* Sadly in the near future we will need more PTSD-related research, not less. In the same vein as an earlier report that an experimental drug can selectively wipe out stressful memories, researchers have recently found that a gene variant, ADRA2B, increases the vividness of emotional memories.
* As they sometimes do Humboldt squid have migrated with warm, low-oxygen waters out of the Baja area and into southern and central California. This time, however, the big squid seem to have arrived for good. What the heck is a Humboldt? Think of a mean-tempered doberman that eats everything it sees. The squid’s reputation as a man-killer is probably exaggerated but commercial fishermen won’t be happy.
Back to the point about caffeine, skin cancer made a good topic for study because like a limited subset of carcinogens, ultraviolet light promotes cancer by acting like a micro-scale DNA chainsaw. Cells cannot divide when DNA has been cut so cell division waits until repair enzymes have fixed the break. Very rarely the repair enzymes make a mistake, which can be a problem if the error happens in the right (wrong) place. Mistakes that inappropriately activate (Ras) or inactivate (p53) specific proteins often kick off a process of unregulated growth and further mutation that eventually leads to cancer.
Interestingly, we knew for a while that caffeine is both a stimulant and a very handy drug for bypassing cell cycle checkpoints. This property, cutting the regulations on cell growth, is one of the reasons why I haven’t had much coffee since I took up science as a career. This study suggests that I should regard caffeine in almost exactly the opposite light. The key is that UV-damaged cells need that arrested period so that the repair enzymes can fix broken DNA. When caffeine shortcuts the mandatory wait time the cell barrels ahead with division without waiting for the repair. Instead of (maybe) a cancer cell you have a dead cell, which is a far more manageable problem.
The caffeine trick won’t do any good for cells that have already become cancerous and it won’t prevent inherited cancers, viral cancers (e.g., human pappilomavirus) or cancers that come from spontaneous mutations in non-dividing tissue. But it will probably work as well or better than sunblock if you’re planning some time at the beach.
Punchy
Tim, can you explain in biochemical terms why the body would break down cholesterol in times of fasting? The major products of said breakdown are bile salts, which seem inappropriate in a time nutrient deficiency.
Not just cut, but polymerized. Thymine dimers.
John Cole
In regards to the squid, can they not be battered, fried, and dipped in a tasty marinara?
The Other Steve
Ok, does this mean I need to drink more red wine? I want to process a lot of cholesterol and fat.
pharniel
so, when can i get a drug that makes my body behave like it’s on the atkins diet so i can have snickerdoodles and bill knapps cake and still drop weight?
Xanthippas
I’ve read about resveratrol before (and have now discovered that you guys have written about it…alot) but I have no idea what supplement you should take or in what amount. How do I know which supplement actually contains high-quality resveratrol (and not just say, rat droppings) and what amount is it recommended that people should take?
Tim F.
David Sinclair, who discovered resveratrol, recommends the Longevinex brand. Wine probably isn’t a great idea since you need several gallons to get a medicinal dose. But then it certainly doesn’t hurt.
The Other Steve
What kind of wine? Can I drink a Shiraz, or must I have Merlot?
Tim F.
Again referring back to Sinclair, red is better than white and pinot noir beats most other reds. The problem with wine, tho, is that the alcohol will kill your liver before the resveratrol makes you immortal. Small doses might help a bit but not to the degree that a 200 milligram pill will do. Drink wine because you like wine.
ImJohnGalt
I take the longevinex now, based on Tim’s original postings and a google of some of the “live longer” newgroups. Some of those folks also suggest you take Quercetin with it. In related news, most recent studies of DHEA suggest it doesn’t do squat.
Can’t say I feel any better as a result, but I don’t feel any worse either.
ImJohnGalt
And FWIW, apparently Sinclair didn’t actually *recommend* Longevinex, but may have consulted on its development. His feeling was that as it tends to oxidize quickly the best way to package it would be in a sealed capsule that was filled in a non-oxygenated environment (I believe they tout Longevinex as being produced in a nitrogen-filled environment).
Punchy
This just doesn’t jive with what’s expected. For example, from wiki:
The breakdown of lipids is understandable, for the gluconeogenesis pathway(s). But a decrease/catabolism in/of cholesterol is antithetical to a fasting state. Tim, what’s the article’s dicussion on this?
Dreggas
A calamari lovers dream!
Ed Willers
Re: AC5
It’s not brain-specific, and is actually quite ubiquitously expressed, especially in the heart and liver. Also, there’s been lots of effort to try and develop isoform-specific adenylyl cyclase activators and inhibitors, but because they are all so similar (especially AC5 and AC6), success has been quite limited. However in Japan they have been using a semi-specific AC5/6 activator to treat late-stage congestive heart failure.
Until now I thought my dissertation topic and research was a waste of time and energy, but being able to reply to a Tim F. post has made it all worthwhile!
TenguPhule
Squid Heathen!
Everyone knows you must eat them with garlic mayo!
Z
Ahhhh! What beautiful news!! First red wine and chocolate being good for you, and now this! I finally have the study to both counter my girlfriend’s nagging to cut down on caffeine AND the sunblock nannies out there who insist I cover every inch of my pasty white skin! Halelujah and pass the coffee pot!!!!
Z
srv
Wasn’t there some North Carolina wine made from some local grape that was much better? Couldn’t find the stuff in CA…
Krista
Wacky stuff. Actual fasting slows down your metabolism, so does resveratrol bypass that effect?
Xanthippas
I looked up the price of Longevinex, and I’d definitely feel worse about shelling that much out of pocket for a product I’m not sure actually will do anything for me. If I can get this blogging gig to pay off though, maybe I can get someone to sponsor me…
The Other Steve
GNC has some stuff for about 1/10th the cost. But now I worry if it was put in pills in a non-oxygenated environment.
Was reading some other article, and the way it read, the mass doses aren’t so helpful because it leaves the bloodstream pretty quickly.
So from that I have decided a steady diet of one glass of Pinot Noir hourly is in order. I’m going to tell my boss at work about this, so he doesn’t think I’m an alcoholic.
Punchy
I’m with Kris. This doesn’t make sense physiologically, although biochemicially I suppose anything is possible. As in any diet, a loss of fat is expected, but as the metabolism accordingly slows, the effect wanes. Just like how the body eventually titrates the level of lipases in the Atkins diet, rendering it pointless after 6 months or so…
Tax Analyst
I think Tim just blinded me with Science…expect to hear from my Lawyer…