Some Medical Aspects of Thermodynamic Theory of Evolution
Medical Market, 25 (1, 1997), P. 6-7, Popular article
The author defined one of the aspects of the thermodynamic theory of the evolution related to the problems of aging, dietetics and other medical and biological disciplines as the following principle: Diets incorporating "evolutionary juvenile" foods of plant and animal origin facilitate longevity and quality of life. The indicator of the "evolutionary juvenility" of a natural foodstuff is determined by its chemical composition and supramolecular structure which in turn depend on ontogenetic and phylogenetic age and the habitat of the organism which acts as the source of that food. An important quantitative parameter of the "longevity value" of a natural foodstuff is the value of the specific Gibbs function fo the formation of its supramolecular structure. The facts revealed to date indicate reliably that nascent thermodynamics of aging and dietetics will pave the way to new medical preparations and diets that would slow down the process of aging and improve public health.
Throughout the 20th century the view has been gaining currency in some scholarly circles that the behavior of biological systems and their evolutionary changes cannot be investigated by methods of classical thermodynamics (thermostatics). That view was based on the notion of living systems (cells, biological tissues, organisms, popoulations, etc) as open systems exchanging matter with the environment.
The fundamentals of thermodynamics were defined in the work of R. Clausius, J. Gibbs, H. Helmholtz and other classics of natural sciences. Thermodynamics makes it possible to investigate the more general properties of macroscopic systems of any nature in a state of thermodynamic equilibrium and transitions between those states.
It yields precise relationships between the measured properties of systems and responds to the question as to how far the process of the evolution of a system shall proceed before an equilibrium has been reached. Thermodynamic theory is especially handy where isolated and closed systems are concerned and as was pointed out in the general case biological systems are not in that number.
Recent studies, however, have revealed that the hierarchical structure of the world as we know it and biosystems in particular makes it possible acting on the basis of certain assumptions and over certain time spans to single out biosystems that are quasi-closed (thermodynamically and kinetically). Such biosystems may be investigated relying on the methods of macrothermodynamics, a new method of investigating open complex heterogeneous systems. Gibbs' theory, the most general and exact physical theory upon which all natural sciences rely, could be extended to living beings as well.
It transpired that the key to the motive forces of the biological evolution is the chemistry of supramolecular structures. Experimental data about the thermodynamic stability of supramolecular structures and variation of the chemical composition of living beings made it possible to substantiate a macrothermodynaic model of ontogeny and phylogeny (G.P.Gladyshev. Thermodynaic theory of the evolution of living beings, 1996. M.: Luch, 86 с., Nova, New-York, US, 1997 ; Izvestiya RАN. Biol. series. , № 4, 1996, pp. 389-397).
According to the theoretical model the tendency of the average specific Gibbs function of supramolecular structures (related to a unit volume or mass of biosystem) to a minimum causes the variation of chemical composition and structure of living systems. It has been shown that as part of ontogeny and also phylogeny and the evolution as a whole, the biological tissues of the organism become enriched with lipids, proteins, polysaccharides etc., which oust water from these biotissues. This is a result of the thermodynamic tendency of the evolutionary processes of the formation of supramolecular structures. It has also been shown that the changes in the chemical composition and structure of biological structures which are adaptive can be be expained from the position of macrothermodynamics.
The use of the Gibbs-Helmholtz equation, other thermodynamic relationships and the correlational equations of the author (Gladyshev G.P. In: Chemical Evolution: Physics of the Origin and Evolution of Life, Ed. J. Chela-Flores and F. Raulin. Kluwer Acad. Publ. Dordrecht-Boston- London. 1996, pp. 221-230) makes it possible to calculate the Gibbs functions of the formation of the supramolecular structures of biological systems such as biological tissues of plants and animals and determine their physiological age. The measurements of the Gibbs function of the formation of supramolecular structures of biological systems can be reliably done using differential scanning calorimetry.
In investigating the aging (ontogeny) of a suprmolecular structure of biological tissue, organ, or any biological system from the position of thermodynamics it makes sense to investigate the effect of physical and chemical factors upon that process. Among these factors are the temperature and pressure of the environment, calorie value and nature of food, effects of synthetic chemical preparations, natural physiologically active compounds, physical exertion, ionizing radiation, physical fields, etc. If ontogeny takes place against a constant background created by the above factors which make up the parameters of the thermostat - the environment, the ontogenesis of a biological system draws to an end at a definite Gibbs function value of the formation of the supramolecular structure of a biological system. That value is close to a minimum.
The "average life expectancy" of an organism is related to its origin and some averaged conditions of the environment. That is why it is strictly "programmed" in an environment typical of a given species. However, any transition to a new environment (in thermodynamic terms it amounts to a transition to a new thermostat) leads to a situation where the system can either age rapidly or become rejuvenated to the extent allowed by the adaptive capabilities of the organism (G.P.Gladyshev, F.I.Komarov. Vestnik RAMN, № 6, 1996, pp. 31-38).
Theory asserts that the rejuvenation of a specific organism, organ, functional system or any local zone of the biological tissue (against a background of constant genetic characteristics of a given organism) is possible through changes in the parameters of its habitat. It also indicates that the variation of the parameters of the habitat (changes in the atmosphere, intensity of physical fields, etc.) cause variation of the stability of the supramolecular structure of a biological system. This variation either ages or rejuvenates the biological tissues of an organism within the limits of its adaptive capability and is a manifestation of the thermodynamic "force" of the environment in the ontogeny of an organism.
It is now possible to quantitatively explain the effects of various medical preparations and diets on the condition of an organism.
For instance, if the diet of a species is changed by increasing the amount of unsaturated fatty acids the supramolecular structures (tissues) containing lipids may become rejuventated. The Gibbs function of the formation of these structures will assume a lesser negative value. This conclusion of the thermodynamic theory of aging is in agreement with the conclusions of clinical practice of treating patients with Linetol obtained from linseed oil. The preparation contains a mixture of ethyl ethers of oleic, linoleic, and linoleneic acids. The effect of that preparation is in strict agreement with thermodynamic calculations. There are many other examples of the rejuvenation of fatty, collagen and other biological tissues.
The thermodynamics of supramolecular structures offers a good explanation of the well-known instances of increasing the life span of animals fed low-calorie diets or administered preparations slowing down food digestion (Medina J.J. The Clock of Ages. 1996. Cambridge: Cambridge Univ. Press, 332 p.). The above phenomena can be explained by the correlation established by the author between the chemical and supramolecular components of the Gibbs function of the formation of the supramolecular structure of the food biomass. In the first approximation the specific Gibbs function of the formation of the supramolecular structure of the biomass correlates with the specific calorie value of the food. This indicates that the specific calorie value of food is related to the thermodynamic stability of its supramolecular structure. The lesser the calorie value of food (specific value) the less negative or positive is the value of the Gibbs function of the formation of the biomass consumed.
A patient using such food enriches his biological tissues with components (molecular building blocks) which take part in the formation of a relatively young biological tissue.
The use of stricter corelations between the chemical component of the Gibbs function of the formation of the biomass (and not the combustion heat- calorie value of the biomass) and the supramolecular component of the Gibbs function of the formation of superstructure of that biomass makes it possible to identify additional opportunities for the rejuvenation of biological tissues.
Given equal calorie value of food depending on the nature of the biomass consumed the effect of rejuvenation may vary and herein lie additional opportunities for the application of macrothermodynamic theory. The calorie value of diets should be lowered not only through the amount of foods consumed, but above all through their molecular and supramolecular value.