Health Agency

Daf-2 was one of the original longevity genes uncovered in nematode worms. Here, Ouroboros looks at the knowledge spiraling out from that discovery: "The insulin-like growth factor (IGF) pathway is one of the longest-known and well-studied regulators of longevity. Extracellular signals (insulin-like peptides) activate insulin-receptor homologs (in worm, DAF-2) which in turn recruit and activate phosphoinositol 3-kinases (AGE-1). PI3Ks convert PIP2 into PIP3, which tethers and recruits other kinases such as AKT-1. Eventually, activation of these upstream kinases results in phosphorylation and inactivation of the longevity assurance gene DAF-16, which encodes a transcription factor that activates (among many other things) stress resistance genes. ... And what does DAF-16 do? It heads to the nucleus and transcriptionally silences the genes encoding the upstream kinases DAF-2, AGE-1 and others - in other words, DAF-16 turns off the genes that could turn off DAF-16. It's a feedback loop! ... The authors argue that this arrangement represents a biological switch between a short-lived 'reproductive state' and a non-reproducing 'longevity state', characterized by DAF-16 activation of stress-resistance and other types of longevity assurance genes."

View the Article Under Discussion: http://ouroboros.wordpress.com/2009/04/30/giving-daf-16-the-upper-hand-a-transcriptional-switch-in-the-igf-pathway/
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

A look at what's going on the tissue engineering labs these days from ScienceDaily: "Cartilage, bones and the internal walls of blood vessels can be created by using common connective tissue cells from human skin. Researchers [have] successfully manipulated these tissue cells to take on different shapes depending on the medium they have been cultivated in. ... This means that it will be much easier to produce autologous tissue, which is tissue created from the patient's own body ... Different strategies have been attempted to instead grow autologous tissue from stem cells, for example those present in bone marrow. These cells, however, can be difficult to harvest, cultivate and store. Compared to these cells connective tissue cells from human skin has great advantages. A small biopsy is often enough to collect a sufficient amount of cells. ... They are the 'weed' cells of the body, very easy to collect and cultivate into the cell type required. They are also very suitable to use to create a personal cell bank. ... The dream is to be able to manipulate connective tissue cells in the human body to develop into specific cell types, for example to create bone cells for broken bones."

View the Article Under Discussion: http://www.sciencedaily.com/releases/2009/04/090430122044.htm
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

A research group believes they have teased out the effects of wine consumption on life expectancy from all the confounding and related effects of diet and lifestyle. It'll take a few more such studies to convince me that this isn't just another artifact relating to inadvertent low-level calorie restriction, however. "Drinking up to half a glass of wine a day may boost life expectancy by five years ... The Dutch authors base their findings on a total of 1,373 randomly selected men whose cardiovascular health and life expectancy at age 50 were repeatedly monitored between 1960 and 2000. ... The researchers found that light long term alcohol consumption of all types - up to 20g a day - extended life by around two extra years compared with no alcohol at all. Extended life expectancy was slightly less for those who drank more than 20g. And men who drank only wine, and less than half a glass of it a day, lived around 2.5 years longer than those who drank beer and spirits, and almost five years longer than those who drank no alcohol at all. Drinking wine was strongly associated with a lower risk of dying from coronary heart disease, cerebrovascular disease, and death from all causes. These results held true, irrespective of socioeconomic status, dietary and other lifestyle habits, factors long thought to influence the association between wine drinking and better health."

View the Article Under Discussion: http://www.sciencedaily.com/releases/2009/04/090429205609.htm
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

Via EurekAlert!: "researchers describe how they are able to reprogram human adult skin cells into other cell types in order to decipher the elusive mechanisms underlying reprogramming. To demonstrate their point, they transformed human skin cells into mouse muscle cells and vice versa. This research shows that by understanding the regulation of cell specialization it may be possible to convert one cell type into another, eventually bypassing stem cells. ... Regenerative medicine provides hope of novel and powerful treatments for many diseases, but depends on the availability of cells with specific characteristics to replace those that are lost or dysfunctional. We show here that mature cells can be directly reprogrammed to generate those necessary cells, providing another way besides embryonic stem cells or induced pluripotent stem cells of overcoming this important bottleneck to restoring tissue function. ... Reprogramming mature cells will likely complement the use of embryonic stem cells in regenerating tissues. By elucidating the regulators of reprogramming [it] may be possible to generate replacement cells in cases where stem cells are not present or not appropriate."

View the Article Under Discussion: http://www.eurekalert.org/pub_releases/2009-04/foas-sst043009.php
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/

EurekAlert! notes a synthesis of previous Parkinson's disease research into a complete understanding of what is taking place: "In a study that reveals the clearest picture to date of neuron death in Parkinson's disease, researchers [have] found that a trio of culprits acting in concert is responsible for killing the brain cells ... symptoms of Parkinson's - including uncontrollable tremors and difficulty in moving arms and legs - are blamed on the loss of neurons from the substantia nigra region of the brain. Researchers had previously suspected dopamine, alpha-synuclein and calcium channels were involved in killing the neurons, but could not pin the deaths on any single molecule. The new paper, along with previous studies, [shows] that it is the combination of all three factors that kills the neurons. The studies found that neurons die because calcium channels lead to an increase of dopamine inside the cell; excess dopamine then reacts with alpha-synuclein to form inactive complexes; and then the complexes gum up the cell's ability to dispose of toxic waste that builds up in the cell over time. The waste eventually kills the cell. ... It may be possible to save neurons and stop Parkinson's disease by interfering with just one of the three factors."

View the Article Under Discussion: http://www.eurekalert.org/pub_releases/2009-04/cumc-pnd042309.php
Read More Longevity Meme Commentary: http://www.longevitymeme.org/news/