Scientists have managed to stop the aging process of the liver
Scientists at Yeshiva University (New York), working under the guidance of Professor Anna Maria Cuervo, blocked the aging process of the liver of mice by stopping the accumulation of harmful proteins inside the cells of the organ.
As the body ages, the ability of cells to get rid of damaged proteins deteriorates. The accumulation of toxic substances occurring in this case is especially pronounced in Alzheimer's disease, Parkinson's disease and other neurodegenerative diseases. The authors claim that their discovery indicates the possibility of preventing age-related deterioration of some body functions by increasing the purification coefficient of waste proteins.
During the experiment, the livers of genetically modified mice aged 22-26 months (the equivalent of an eighty-year-old human) purified the blood as efficiently as the organs of four times younger animals. At the same time, the livers of normal mice in the control group were already beginning to show signs of insufficiency.
The authors believe that the benefits of restoring the mechanisms of cell purification extend far beyond one organ. According to Cuervo, the results obtained are particularly significant in relation to diseases such as Parkinson's and Alzheimer's diseases caused by the accumulation of abnormal or pathological proteins in neurons.
In a healthy body, an intracellular control system called chaperone-mediated autophagy detects, breaks down and destroys damaged proteins. Specialized chaperone proteins transfer toxic material to lysosomes – membrane vesicles filled with enzymes. After that, the receptor molecule transfers the protein into the lysosome, where it is rapidly cleaved.
As we age, the effectiveness of the receptors decreases, which leads to the accumulation of abnormal proteins. In the liver, this leads to the development of insulin resistance, as well as to the loss of the ability to metabolize carbohydrates, fats, as well as alcohol and other toxic substances. This may also be the cause of a violation of the liver's ability to remove drug residues at an age when they become part of the daily diet.
In genetically modified animals, scientists compensated for the loss of receptors by adding additional copies of the gene encoding them. This was enough to maintain the "purity" of the liver and prove that cleansing the cells improves their work.
Experts say that Cuervo has not yet published data according to which the tested genetic modification prolongs the life of animals. Moreover, she is currently working with pharmaceutical companies to identify drugs that can trigger the work of inactivated receptors or increase their activity.
The authors believe that activating the excretion of damaged proteins can increase life expectancy and improve the functioning of all body tissues. They suggest that such an effect can be achieved with the help of a rational diet.
Portal "Eternal youth" www.vechnayamolodost.ru based on ABC materials – Scientists stop the aging process
01.10.2008