Aging is reversible

Scientists from Boston Children's Hospital found that the transformation of skin cells taken from patients with premature aging into induced pluripotent stem cells lengthens telomeres in them and activates telomerase.

Telomeres – repetitive DNA sequences located at the ends of chromosomes – shorten with each division of ordinary cells, which is one of the generally recognized causes of aging. Telomerase (an enzyme consisting of two pairs of protein globules and an RNA chain, a complementary repeating sequence of six nucleotides that make up telomeres) it actively functions in stem and cancer cells, restoring their telomeres to their original length and protecting cells from aging. Therefore, telomerase is the object of close attention of both oncologists and specialists trying to understand the mechanisms of aging and find ways to delay it.

Mutations of genes encoding components of the telomerase complex are the cause of congenital dyskeratosis – one of the types of progeria, hereditary diseases characterized by premature aging. The disease manifests itself in abnormal pigmentation of the skin, keratinization of the mucous membranes and damage to other rapidly renewing tissues. The most serious consequence of telomerase dysfunction is a violation of the hematopoietic function of the bone marrow, which ultimately leads to early death from infections or from bleeding. Cells of patients with congenital dyskeratosis grow much worse in cultures than cells of healthy people.

Previously, it was found that reprogramming is able to lengthen telomeres in cells taken from healthy people. But the question of whether the same thing would happen in induced pluripotent stem cells with initially defective telomerase remained open.

Researchers working under the guidance of Dr. Suneet Agarwal, using genetic manipulation, reprogrammed the skin cells of three patients suffering from congenital dyskeratosis into an embryonic state. Despite the presence of mutations in the genes encoding the components of telomerase, the resulting induced pluripotent stem cells were able to grow and divide, and their telomeres were not shortened with each division, but lengthened.

The results of the study can be used both to develop methods of progeria therapy and to study the activity of telomerase and the development of senile diseases. For example, the question remains unclear whether cells taken from people suffering from age-related diseases such as Parkinson's disease and Alzheimer's disease, and reprogrammed into embryonic ones, will show characteristic signs of the disease soon after reprogramming or not? In addition, the new development is a convenient method for studying telomerase involved in the development of oncological diseases.

The article by Suneet Agarwal et al. "Telomere elongation in induced pluripotent stem cells from dyskeratosis congenita patients" was published online on February 17, 2010 in the journal Nature.

Daria Chervyakova
Portal "Eternal youth" http://vechnayamolodost.ru based on Technology Review: Rewinding the Clock for Aging Cells24.02.2010