Testosterone rejuvenates, but not everyone
Researchers at the Universities of Boston and Texas, working under the guidance of Dr. Monty Montano, have found that the concentration of nine blood proteins changes with age, but these changes can be partially corrected by the introduction of the male sex hormone testosterone.
As part of the work, scientists compared the serum protein levels of two groups of healthy men: young men aged 18-35 years and elderly men aged 60-75 years.
It turned out that the concentrations of seven of the analyzed proteins were lowered in elderly men: growth factors (insulin-like growth factor–1 - GF-1, interleukin–7 - IL-7, interleukin–12p40 - IL-12p40, platelet growth factor–beta - PDGFbeta), proteins involved in the immune response (epithelial neutrophil-activating protein-78 – ENA78, macrophage inflammation protein-1-beta –MIP-1beta, interferon-gamma-induced protein 10 – IP-gamma-10), as well as procollagen type III – PIIINP. The level of another protein also involved in the development of the immune response, monokine induced by gamma interferon (MIG), on the contrary, was increased.
Testosterone therapy, traditionally used to treat age-related muscle tissue atrophy, not only increased the volume of muscle mass and the level of appetite-suppressing hormone leptin in both groups of men, but also increased the levels of procollagen type III and insulin-like growth factor-1 in young and some older men.
According to Dr. Montano, the identified blood proteins, whose levels change with normal aging, are also related to maintaining muscle functionality (procollagen type III and insulin-like growth factor-1) or are involved in the regulation of the immune system, possibly providing an age-related decrease in the activity of T-lymphocytes and neutrophils. In addition, all of these proteins are involved in signaling mechanisms mediated by protein kinase B (AKT), nuclear factor-kappa-beta (NF-kappa-beta) and transforming growth factor-beta (TGF-beta), known for their involvement in aging processes.
The proteins identified by the researchers are potential biomarkers of healthy aging. However, this set of indicators is hardly suitable for a personal assessment of biological age due to individual differences in the concentrations of each of the proteins. And, as has been repeatedly noted, testosterone replacement therapy in old age is not shown to everyone and does not guarantee the restoration of weakened muscles and the immune system.
Article by Camellia Banerjee et al. Identification of serum biomarkers for aging and anabolic response was published on June 20 in the journal Immunity & Aging.
Evgeniya Ryabtseva
Portal "Eternal youth" www.vechnayamolodost.ru Based on ScienceDaily: Proteins Used to Map the Aging Process.
22.06.2011