09 February 2009

In search of the elixir of youth

On January 27, the IX scientific conference of young scientists entitled "Topical issues of gerontology and Geriatrics" was held at the Institute of Gerontology of the Academy of Medical Sciences of Ukraine, and on January 28-29, a scientific and practical conference "Modern aspects of the diagnosis and treatment of cognitive disorders in aging" was held in the Congress hall of the Kievsky President Hotel.

These events were dedicated to the memory of Vladimir Veniaminovich Frolkis, a world–renowned scientist, academician of the National Academy of Sciences and the Academy of Medical Sciences of Ukraine, a professor who would have turned 85 this year.

"Not taking care of the elderly is like destroying a house during the day in which you will sleep at night," said this outstanding physiologist and gerontologist of our time, who devoted his life to studying the fundamental mechanisms of aging.

During the above-mentioned conferences with international participation, the problems of modern gerontology were considered, many myths were debunked and practical answers were given to questions relevant to doctors of Ukraine.

"Nothing lasts forever under the moon," scientists of all eras sought to refute this thesis. Legends about the philosopher's stone and the elixir of youth were replaced by theories of aging, Faust sold his soul for the secret of immortality, but the fact remained. And so gerontology appeared – the science of biological, medical, social, psychological aspects of aging, its causes and ways to combat it. V. Frolkis, a world–renowned scientist, made a significant contribution to its development.

In the 60-70 years of the twentieth century, V. Frolkis developed an adaptive-regulatory theory of aging, which received worldwide recognition. According to its provisions, age-related development and life expectancy are determined by the balance of two processes: anti-aging occurs in parallel with aging (vitaukt: from Lat. vita – life, auctum – increase), which is aimed at maintaining the viability of the organism, its adaptation, increasing life expectancy. Ideas about vitaukt have become widespread – in 1995, the first international congress dedicated to this problem was held in the USA.

An essential component of V. Frolkis' theory of aging is the gene-regulatory hypothesis of aging developed by him.

He believed that the gene-regulatory mechanisms of aging are the basis for the development of common types of so–called age-related pathology - atherosclerosis, cancer, diabetes mellitus (DM), Parkinsonism, Alzheimer's disease.

The scientist also considered neurohumoral mechanisms of aging. The results of a large cycle of experiments conducted by the author of the theory and his colleagues proved that in the conditions of an integral organism, the leading links in the mechanisms of aging are uneven changes in the functions of the central nervous system, neurohormonal connections, weakening of nervous trophic control over tissues. V. Frolkis drew attention to the similarity of many manifestations of aging and stress, and formulated the idea of stress-age-a syndrome that can lead to the development of pathology. From the pen of this outstanding gerontologist came out more than 700 scientific papers published in Ukraine and abroad (in the USA, Austria, Switzerland, Germany, etc.). He was also one of the founders and vice-president of the AMN of Ukraine.

The welcoming speech was delivered by: Yuriy Zozulya, Academician of the NAS and AMN of Ukraine, Vice-President of the AMN of Ukraine, Yuriy Kundiev, Academician, Vice-President of the AMN of Ukraine, Platon Kostyuk, Academician of the NAS and AMN of Ukraine, Director of the Institute of Physiology of the NAS of Ukraine, Isaac Trachtenberg, Academician of the AMN of Ukraine, Oleg Kulchitsky, Professor, Deputy Director Institute of Gerontology of the Academy of Medical Sciences of Ukraine for scientific and organizational work. Nikita Mankovsky, Professor, Honored Scientist, scientific consultant of the Department of Age Physiology and Pathology of the Nervous System of the Institute of Gerontology of the Academy of Medical Sciences of Ukraine, focused the attention of those present on the need for close professional cooperation of scientists from Ukraine, Russia and other European countries.

Alexander Vaiserman, MD, Chief Researcher of the Laboratory of Mathematical Modeling of Aging Processes at the Institute of Gerontology of the Academy of Medical Sciences of Ukraine in the report "Legends and myths of modern Gerontology" examined the main theories of aging from unexpected sides. According to the speaker, the worldview of modern gerontologists is largely based on a system of ideas (developed in the middle of the twentieth century), which today are questionable.

Now the most authoritative is the free radical hypothesis of aging, proposed by Denchen Harman in 1956. She considers free radicals that are formed in the body during metabolism and are capable of damaging any biopolymers – proteins, lipids, DNA. According to this theory, such damage to cellular structures, accumulating, leads to aging and age-related diseases: cancer, diabetes, diseases of the cardiovascular system (CCC), Alzheimer's disease. Antioxidants – traps and neutralizers of free radicals are able to counteract these processes.

Thus, for about 50 years, antioxidants have been considered one of the most effective geroprotectors (drugs that can slow down the aging process). However, free radicals are an important component of processes in the body – they are involved in cell proliferation and differentiation, as well as in the functioning of the immune system (for example, thanks to active forms of oxygen, immunocompetent cells can cope with infectious agents).

In recent years, the antioxidant paradox has been widely discussed: when the functional state of a cell changes, any antioxidant can become a pro–oxidant - that is, it is able to enhance oxidative processes. The results of recent studies show against the free radical theory of aging. Thus, nematodes (roundworms-parasites) with increased activity of the endogenous antioxidant enzyme superoxide dismutase were bred: this made it possible to reduce oxidative stress, but had no effect on life expectancy (Doonan R. et al., 2008). Thus, antioxidants are not able to slow down the aging process.

Over 50 years of active study of geroprotectors, about 1000 scientific papers have been prepared, in which positive results on life extension have been obtained. However, there is an opinion that their effectiveness is reduced to hormesis – this is the effect of paradoxical stimulation, which can be provided by any damaging substance at a dose of 1% lethal. According to the speaker, there is no serious reason to believe that geroprotectors really do not act in the same way as hormetic substances.

Another theory of aging is the telomeric hypothesis (Olovnikov A., 1971). Fibroblasts in vitro are capable of dividing no more than 50 times – the Hayflick limit, discovered in 1961. The telomeric hypothesis explains the presence of this limit by the fact that with each cycle of cell division, the end sections of chromosomes – telomeres are shortened. When their length becomes incompatible with the process of division, the cell goes into the stage of cellular aging and dies. This hypothesis was confirmed in 1986 with the discovery of an enzyme called telomerase, which can increase telomeres to the initial level in cells that always divide (for example, cancer cells).

However, according to the author of the telomeric hypothesis, in a living organism, cells never have time to reach the Hayflick limit, having exhausted their potential of divisions: "The telomeric hypothesis of aging is beautiful in all respects, except for one thing – it is wrong." Thus, according to A. Weisserman, the future of gerontology is connected, first of all, with revolutionary discoveries in the study of stem cells.

Moving from theory to practice, on January 28-29, modern aspects of the diagnosis and treatment of cognitive impairments that occur with aging were considered. Cognitive functions are usually understood as the most complex functions of the brain, with the help of which the process of rational cognition of the world is carried out:

  • memory is the ability of the brain to assimilate, store and reproduce the information necessary for current activity;
  • gnosis is the ability to perceive information, process it and synthesize elementary sensory sensations into holistic images;
  • speech – the ability to exchange information through utterances;
  • praxis – the ability to acquire, maintain and use a variety of motor skills;
  • intelligence is the ability to compare information, find common and different things, make judgments and conclusions.

Professor Amos Korczyn (Korczyn A.D., Tel Aviv University Medical School) in his report "Vascular cognitive impairment" defined the concept of vascular dementia (dementia) as a group of severe cognitive impairments resulting from cerebral ischemia or hemorrhage, and also highlighted the prevalence and complexity of the diagnosis of mixed dementia.

Risk factors for dementia in general were named:

  • old age;
  • belonging to the female sex;
  • a history of head trauma;
  • low level of education;
  • arterial hypertension;
  • hyperlipidemia, hypercholesterolemia;
  • SD;
  • hyperhomocysteinemia.

The commonality of risk factors for cardiovascular diseases and dementia (both vascular genesis and dementia in Alzheimer's disease) has become an important discovery in recent years. Criteria for the diagnosis of vascular dementia are deterioration of memory and other cognitive functions, which affects social function or occupation, focal neurological symptoms.

Mixed dementia, according to the speaker, is a diagnosis that is often not given due importance. According to pathologists, the accuracy of the clinical diagnosis of Alzheimer's disease and vascular dementia ranges from 30-70%. Therefore, Amos Korchin argues that the most common is dementia of mixed genesis. There is no elderly person who does not have any changes that occur in Alzheimer's disease, and in the presence of concomitant vascular disorders, this combination leads to the development of dementia.

Igor Damulin, MD, Professor of the I.M. Sechenov Moscow Medical Academy, presented a report on "Cognitive impairment in dyscirculatory encephalopathy (DEP)". According to him, the clinical picture of DEP is a slowdown in the speed of mental processes, or primary cognitive disorders, which are often combined with motor disorders, which leads to social maladaptation of patients.

It is necessary to distinguish between DEP and changes associated with the physiological process of aging. Thus, a decrease in cognitive functions with a variable degree of severity (may be absent) is observed in people over the age of 50, and only 1% of patients have cognitive impairment progressing within 1 year before the onset of dementia.

In the diagnosis, it is informative to talk with the patient and find out the anamnesis, as well as to conduct special tests to assess the ability to perform actions, the degree of adaptation to everyday conditions and the safety of work skills (if the patient is working).

Neuropsychological testing is:

  • objectification;
  • diagnosis of the initial stages of dementia, when it is necessary to make socially important decisions;
  • determination of legal capacity.

An interesting and informative presentation was made by Tamara Mishchenko, head of the Department of Vascular Pathology of the Brain of the Institute of Neurology, Psychiatry and Narcology of the Academy of Medical Sciences of Ukraine, professor on the topic "Asymptomatic brain infarctions and cognitive disorders". According to the speaker, dementia is noted in 17-20 million people in the world. The most common is dementia in Alzheimer's disease, followed by vascular dementia. In Europe, it was diagnosed in 3.7 million people, of which 0.8 million had vascular. T. Mishchenko also presented data on our country: in Ukraine, dementia was diagnosed in 62,180 patients, of whom 26,220 patients or 41% were vascular. Every year, about 5 thousand new cases of dementia are noted, which is associated with the possibility of a more accurate diagnosis of the disease, the need for help and a true increase in the incidence rate.

One of the causes of vascular dementia is an asymptomatic (subclinical, silent, mute) cerebral infarction. Due to the widespread introduction and availability of neuroimaging methods (magnetic resonance imaging, computed tomography), foci of brain damage that do not have clinical manifestations are detected. If a patient has suffered a silent brain infarction, the risk of cognitive impairment and dementia increases almost 4 times: "Small strokes are big problems."

In addition to the well-known risk factors for the development of asymptomatic cerebral infarction (such as old age, belonging to the female sex, genetic predisposition, smoking, uncontrolled hypertension, diabetes), there are others whose role is being actively studied today: chronic inflammation, elevated homocysteine levels in the blood, sleep apnea, depression, migraine.

According to T. Mishchenko, in our country there is an opportunity for the treatment and prevention of the development of cognitive disorders. In general, asymptomatic cerebral infarction is diagnosed 5-8 times more often than symptomatic, which makes it an important medical and social problem.

Natalia Bachinskaya, Professor, Head of the Department of Age Physiology and Pathology of the Nervous System of the Institute of Gerontology of the Academy of Medical Sciences of Ukraine – the main organizer of the conference "Modern aspects of the diagnosis and treatment of cognitive impairment in aging" – presented a report on the features of medical and ethical aspects of the management of older patients with cognitive impairment of varying degrees. The speaker also reported that the Association for Alzheimer's Disease has been working on the basis of the Institute of Gerontology of the Academy of Medical Sciences of Ukraine since 2000, which provides assistance to patients with cognitive impairments, their relatives, as well as specialists of various profiles working in this field.

According to the organizers, the events were a continuation of a series of conferences and seminars devoted to topical issues of epidemiology, etiology, pathogenesis, clinic, diagnosis, treatment, as well as management of older patients with cognitive impairments of varying degrees.

Press service of the Weekly PHARMACYPortal "Eternal youth" www.vechnayamolodost.ru


09.02.2009

Found a typo? Select it and press ctrl + enter Print version