Telomeres can lengthen?

[dime]

This is amazing study, showing that certain lifestyle changes can cause telomeres to lengthen! They became 10% longer over 5 years, in this particular study.

http://www.medicaldaily.com/healthy-lif ... ing-257068

Study: http://www.thelancet.com/journals/lanon ... 8/abstract

I'll try to get the full article.

At the outset of the study, 10 of the men changed their lifestyles comprehensively. These modifications included adopting a plant-based diet (high in fruits, vegetables, and unrefined grains, and low in fat and refined carbohydrates), exercising moderately (walking 30 minutes a day, six days a week), and reducing stress (gentle yoga-based stretching, breathing, and meditation). These 10 patients also participated in weekly group support meetings.

The other 25 men made no changes whatsoever to their lifestyle. Next, the researchers took blood samples at five years and compared the telomere length and telomerase enzymatic activity with measures taken at the beginning of the study, and then they compared and analyzed the results in relation to the degree of lifestyle changes.
Telomere length increased by approximately 10 percent in the group of 10 men who had changed their lifestyle, while it decreased by about three percent in the group of 25 men who had made no lifestyle changes whatsoever. The researchers also found that the more the men followed the improved lifestyle program, the more dramatic their telomere length.

[RRM]

Actually, they said relative

We took blood samples at 5 years and compared relative telomere length and telomerase enzymatic activity

Relative telomere length is compared to its 'normal' / 'average' / control group length given a specific age.
So, the shortening of telomeres continues, but at a slower rate, so that 5 years later,
its (relative) length has increased (compared to age-matched controls).
In this study (Ornish D et al) they conclude:

lifestyle intervention was associated with increases in relative telomere length after 5 years of follow-up, compared with controls, in this small pilot study
...
telomerase activity ... was not associated with adherence to lifestyle changes

Short telomeres are not just the result of (cell) stress, but also yield more DNA errors.
So that's why ageing often seems accelerated at old age.
"Critically short telomeres may trigger chromosomal aberrations and produce genomic instability leading to cancer development".
Martinez-Delgado B et al

Hereditary ...tumors were characterized by shorter telomeres comparing to sporadic tumors.
Considering all tumors, tumor grade was a strong risk factor determining the proportion of short telomeres

Also interesting:

Gewirtz DThe literature relating to this topic is inconclusive, with some reports appearing to be consistent with a direct relationship between autophagy and senescence and others indicative of an inverse relationship.

Naturally, its seems logic that autophagy (as preventing cell death) slows down telomere shortening.
In this quoted study the author regards telomere shortening as "an internal form of stress" .... (rather than as an 'indicator' of stress)

[dime]

Well spotted! These articles on the internet have interpreted it a bit wrongly and completely missed the relative part. They all say lengthten, rather than slow down shortening.