TA-65 safety claims

Earlier I posted about TA-65, a telomerase activator, which some hope could reverse some of the effects of aging. Amiya Sarkar is a doctor in Calcutta who writes a fascinating blog on physiology and physics. He and I have emailed back and forth for a couple years now, starting with a very cool idea he had for an inexpensive open-source electrocardiogram. (One of these days we really need to get that project back on track.)

Amiya expressed the concern that any telomerase activator could be viewed as a potential cancer risk. Cancerous cells use telomerase to support the unlimited replication that characterizes cancer. The folks at Sierra Sciences openly recognize this concern, and give reasons why they believe it's a red herring, on this webpage:

In most cases (85–95%), cancers accomplish this indefinite cell division by turning on telomerase. For this reason, forcing telomerase to turn off throughout the body has been suggested as a cure for cancer, and there are several telomerase inhibitor drugs presently being tested in clinical trials.

So, anti-aging scientists must be out of their minds to want to turn the telomerase gene on, right?

No! Although telomerase is necessary for cancers to extend their lifespan, telomerase does not cause cancer. This has been repeatedly demonstrated: at least seven assays for cancer have been performed on telomerase-positive human cells: the soft agar assay, the contact inhibition assay, the mouse xenograft assay, the karyotype assay, the serum inhibition assay, the gene expression assay, and the checkpoint analysis assay. All reported negative results...

Paradoxically, even though cells require telomerase to become dangerous cancers, turning on telomerase may actually prevent cancer. This is not just because the risk of chromosome rearrangements is reduced, but also because telomerase can extend the lifespan of our immune cells, improving their ability to seek out and destroy cancer cells.

In support of this, they list several papers.

• Jiang, X.-R. et al. Telomerase expression in human somatic cells does not induce changes associated with a transformed phenotype. Nature Genet., 21, 111–114 (1999)
  
• Morales, C.P., et. al. Absence of cancer-associated changes in human fibroblasts immortalized with telomerase. Nature Genet., 21, 115–118 (1999)
  
• Harley, C. B. Telomerase is not an oncogene. Oncogene 21(4): 494-502 (2002).

From other writings on their website, and from their postings to Twitter and Facebook, it's clear that the Sierra Sciences folks are 100% confident that telomerase activators pose zero cancer risk. They are in a much better position to know about this than I. But if I started taking TA-65 and they were somehow mistaken, they wouldn't be the ones at risk for cancer. I hope to find out about those seven assays and try to read those three papers in my abundant spare time, and maybe discuss the matter with my doctor. (My present circumstances do not permit me to afford TA-65 even if I decide I want it.) Wouldn't it be cool if the Sierra Sciences people turn out to be correct...

Telomeres and aging

Recently I became aware of Sierra Sciences, a startup founded by William Andrews, previously of Geron. Andrews had done a lot of research on telomeres and telomerase.

Your cells have nuclei in them where your DNA is wadded up into packets called chromosomes. On the ends of the DNA strands there's a thing called a telomere. It protects the DNA from unravelling, like the little plastic tube on the end of your shoelace. Our telomeres shorten as we get older, and longer telomeres are strongly correlated with youth and vigor and health. There are many contributors to ageing but telomere length is currently regarded as one of the most urgent and one of the best understood.

Our reproductive cells do not suffer this effect. If we passed on shorter telomeres to our kids, they wouldn't live long, and they probably couldn't have kids of their own. To accomplish this, our reproductive cells produce stuff called telomerase which protects the telomeres from shortening. Here's the cool part: the gene for producing telomerase is present in ALL our cells, but it's only switched on in the reproductive cells. So there's a research push to find a telomerase activator that switches on the gene in all our cells. Sierra Sciences is one of the companies involved in this research.

You can buy a telomerase activator today, called TA-65. It's expensive, about $1500 per month, I think. But I haven't yet found any compelling evidence that it's a scam or a significant health risk. So I'm toying with the idea of trying it for a few months and see if I feel any different.

There is also a clinical test to measure the length of your telomeres. I know it exists but I don't know much more about it at the moment.