Entropy Stress and Scaling of Vital Organs over Life Span Based on Allometric Laws

Thermodynamic Analysis to Evaluate the Effect of Diet on Brain Glucose Metabolism: The Case of Fish Oil

Inefficient glucose metabolism and decreased ATP production in the brain are linked to ageing, cognitive decline, and neurodegenerative diseases (NDDs). This study employed thermodynamic analysis to assess the effect of fish oil supplementation on glucose metabolism in ageing brains. Data from previous studies on glucose metabolism in the aged human brain and grey mouse lemur brains were examined. The results demonstrated that Omega-3 fish oil supplementation in grey mouse lemurs increased entropy generation and decreased Gibbs free energy across all brain regions. Specifically, there was a 47.4% increase in entropy generation and a 47.4 decrease in Gibbs free energy in the whole brain, indicating improved metabolic efficiency. In the human model, looking at the specific brain regions, supplementation with Omega-3 polyunsaturated fatty acids (n-3 PUFAs) reduced the entropy generation difference between elderly and young individuals in the cerebellum and particular parts of the brain cortex, namely the anterior cingulate and occipital lobe, with 100%, 14.29%, and 20% reductions, respectively. The Gibbs free energy difference was reduced only in the anterior cingulate by 60.64%. This research underscores that the application of thermodynamics is a comparable and powerful tool in comprehending the dynamics and metabolic intricacies within the brain.

Mechanisms of Cardiac Repair in Cell Therapy

Heart failure is an important cause of morbidity and mortality. More than 20 years ago, special interest was drawn to cell therapy as a means of restoring damaged hearts to working condition. But progress has not been straightforward as many of our initial assumptions turned out to be wrong. In this review, we critically examine the last 20 years of progress in cardiac cell therapy and focus on several of the popular beliefs surrounding cell therapy to illustrate the mechanisms involved in restoring heart function after cardiac injury. Are they true or false?

Thermodynamic Assessment of the Effects of Intermittent Fasting and Fatty Liver Disease Diets on Longevity

Organisms uptake energy from their diet and maintain a highly organized structure by importing energy and exporting entropy. A fraction of the generated entropy is accumulated in their bodies, thus causing ageing. Hayflick's entropic age concept suggests that the lifespan of organisms is determined by the amount of entropy they generate. Organisms die after reaching their lifespan entropy generation limit. On the basis of the lifespan entropy generation concept, this study suggests that an intermittent fasting diet, which means skipping some meals without increasing the calories uptake in the other courses, may increase longevity. More than 1.32 million people died in 2017 because of chronic liver diseases, and a quarter of the world's population has non-alcoholic fatty liver disease. There are no specific dietary guidelines available for the treatment of non-alcoholic fatty liver diseases but shifting to a healthier diet is recommended as the primary treatment. A healthy obese person may generate 119.9 kJ/kg K per year of entropy and generate a total of 4796 kJ/kg K entropy in the first 40 years of life. If obese persons continue to consume the same diet, they may have 94 years of life expectancy. After age 40, Child-Pugh Score A, B, and C NAFLD patients may generate 126.2, 149.9, and 272.5 kJ/kg K year of entropy and have 92, 84, and 64 years of life expectancy, respectively. If they were to make a major recommended shift in their diet, the life expectancy of Child-Pugh Score A, B, and C patients may increase by 29, 32, and 43 years, respectively.

Biothermodynamics of Viruses from Absolute Zero (1950) to Virothermodynamics (2022)

Biothermodynamics of viruses is among the youngest but most rapidly developing scientific disciplines. During the COVID-19 pandemic, it closely followed the results published by molecular biologists. Empirical formulas were published for 50 viruses and thermodynamic properties for multiple viruses and virus variants, including all variants of concern of SARS-CoV-2, SARS-CoV, MERS-CoV, Ebola virus, Vaccinia and Monkeypox virus. A review of the development of biothermodynamics of viruses during the last several decades and intense development during the last 3 years is described in this paper.

Diet-dependent entropic assessment of athletes' lifespan

Life expectancies of the athletes depend on the sports they are doing. The entropic age concept, which was found successful in the previous nutrition studies, will be employed to assess the relation between the athletes' longevity and nutrition. Depending on their caloric needs, diets are designed for each group of athletes based on the most recent guidelines while they are pursuing their careers and for the post-retirement period, and then the metabolic entropy generation was worked out for each group. Their expected lifespans, based on attaining the lifespan entropy limit, were calculated. Thermodynamic assessment appeared to be in agreement with the observations. There may be a significant improvement in the athletes' longevity if they shift to a retirement diet after the age of 50. The expected average longevity for male athletes was 56 years for cyclists, 66 years for weightlifters, 75 years for rugby players and 92 years for golfers. If they should start consuming the retirement diet after 50 years of age, the longevity of the cyclists may increase for 7 years, and those of weightlifters, rugby players and golfers may increase for 22, 30 and 8 years, respectively.

A Brief on Biological Thermodynamics for Human Physiology

Thermodynamics, the science of energy interactions, governs the direction of processes found in nature. While the subject finds wide applications in science and technology, its connection to biological sciences and in particular to bio-engineering is becoming increasingly important. In this work, after a brief introduction to the fundamental concepts in thermodynamics, we focus on its application in human physiology. A review of application of thermodynamics to the interaction between human body and environment is presented. Research works on biological systems such as the nervous system and the cardiovascular systems are summarized. The thermodynamics of metabolism is reviewed, and finally, the role of the subject in understanding and combating diseases is highlighted.

Performance analysis of human respiratory system based on the second law of thermodynamics

The purpose of this study is to develop a comprehensive thermodynamic model of the human respiratory system and quantify the effects of inspiratory air temperature, relative humidity (RH), lung capacity and O₂ fluctuation in metabolic reaction on the human respiratory system under three different physiological conditions, i.e. rest, moderate level of physical activity and extreme level of physical activity. Therefore, a second law-based analysis has carried out for the human respiratory system. It is observed that exergetic efficiency decreases by 21% and 16.5% during moderate and extreme level of activity respectively as compared to the physical condition of rest. The respiratory efficiency also increases with the increase in inspiratory air temperature and RH. For a given inspiratory air temperature, an increase in lung volume leads to a reduction in the efficiency. Increase in TV with a high airflow rate gives a higher magnitude of efficiency, such a situation appearing when a person's lung compliance harmed due to diseases. The respiratory efficiency decreases up to 2% with the increase in O₂ percentage. The efficiency of the respiratory system is in maximum during rest followed by an extreme and moderate level of activity. However, with the controlled supply of O₂, the efficiency of the human respiratory performance increases with the decrease in O₂ percentage. Due to partial oxidation of glucose at a reduced O₂ level, exergy input from the metabolic reaction is less leading to increased exergetic efficiency.

Why women may live longer than men do? A telomere-length regulated and diet-based entropic assessment

BACKGROUND & AIMS

Empirical analyses of the data available around the word concluded that women have longer life span now, when compared to the men. Available literature unfortunately could not offer full answers to this observation. The "entropic age" concept suggests that ageing related changes in the body, such as loss of molecular functions and overwhelming of the maintenance systems, may be explained in terms of entropy generation.

METHODS

Telomere-length regulated entropic assessment based on metabolic activity with four different diets carried out.

RESULTS

Estimates of the life expectancy of the women on all of these diets is longer than those of the men. Faster shortening of the telomere lengths in men was the major reason of the shorter life expectancy. The highest and the lowest life expectancy for women were estimated with Mediterranean and the vegetarian diets, respectively; men were estimated to have the longest life span with the vegetarian diet and the shortest life span with the ketogenic diet.

CONCLUSIONS

A higher rate of metabolism causes higher entropy generation and hints correlations that can be helpful in future ageing research. Faster shortening of the telomere lengths in men was the major reason of the estimation of the shorter life span for men.

Ranking Renewable and Fossil Fuels on Global Warming Potential Using Respiratory Quotient Concept

Carbon dioxide (CO2) is one of the greenhouse gases which cause global warming. The amount of fossil fuels consumed to meet the demands in the areas of power and transportation is projected to increase in the upcoming years. Depending on carbon content, each power plant fuel has its own potential to produce carbon dioxide. Similarly, the humans consume food containing carbohydrates (CH), fat, and protein which emit CO2 due to metabolism. The biology literature uses respiratory quotient (RQ), defined as the ratio of CO2 moles exhausted per mole of O2 consumed within the body, to estimate CO2 loading in the blood stream and CO2 in nasal exhaust. Here, we apply that principle in the field of combustion to relate the RQ to CO2 emitted in tons per GJ of energy released when a fuel is combusted. The RQ value of a fuel can be determined either from fuel chemical formulae (from ultimate analyses for most liquid and solid fuels of known composition) or from exhaust gas analyses. RQ ranges from 0.5 for methane (CH4) to 1 for pure carbon. Based on the results obtained, the lesser the value of “RQ” of a fuel, the lower its global warming potential. This methodology can be further extended for an “online instantaneous measurement of CO2” in automobiles based on actual fuel use irrespective of fuel composition.

Entropy Production and the Pressure-Volume Curve of the Lung

We investigate analytically the production of entropy during a breathing cycle in healthy and diseased lungs. First, we calculate entropy production in healthy lungs by applying the laws of thermodynamics to the well-known transpulmonary pressure–volume (P–V) curves of the lung under the assumption that lung tissue behaves as an entropic spring similar to rubber. The bulk modulus, B, of the lung is also derived from these calculations. Second, we extend this approach to elastic recoil disorders of the lung such as occur in pulmonary fibrosis and emphysema. These diseases are characterized by particular alterations in the P–V relationship. For example, in fibrotic lungs B increases monotonically with disease progression, while in emphysema the opposite occurs. These diseases can thus be mimicked simply by making appropriate adjustments to the parameters of the P–V curve. Using Clausius's formalism, we show that entropy production, ΔS, is related to the hysteresis area, ΔA, enclosed by the P–V curve during a breathing cycle, namely, ΔS=ΔA∕T, where T is the body temperature. Although ΔA is highly dependent on the disease, such formula applies to healthy as well as diseased lungs, regardless of the disease stage. Finally, we use an ansatz to predict analytically the entropy produced by the fibrotic and emphysematous lungs.

Calculating Stress: From Entropy to a Thermodynamic Concept of Health and Disease

To date, contemporary science has lacked a satisfactory tool for the objective expression of stress. This text thus introduces a new-thermodynamically derived-approach to stress measurement, based on entropy production in time and independent of the quality or modality of a given stressor or a combination thereof. Hereto, we propose a novel model of stress response based on thermodynamic modelling of entropy production, both in the tissues/organs and in regulatory feedbacks. Stress response is expressed in our model on the basis of stress entropic load (SEL), a variable we introduced previously; the mathematical expression of SEL, provided here for the first time, now allows us to describe the various states of a living system, including differentiating between states of health and disease. The resulting calculation of stress response regardless of the type of stressor(s) in question is thus poised to become an entirely new tool for predicting the development of a living system.

"Stress entropic load" as a transgenerational epigenetic response trigger

Epigenetic changes are generally based on the switching of alternative functional or structural states and result in the adaptation of cellular expression patterns during proliferation, differentiation or plastic changes in the adult organism, whereas some epigenetic information can be passed on other generations while other is not. Hence, the principal question is: why is some information reset or resolved during the meiosis process and other is passed from one generation to another, or, in other words: what "adaptation trigger" level initiates transgenerationally transmitted epigenome change? Hereto, we propose a theory which states that stress, or, more specifically, the energy cost of an individual's adaptation to stress, represents a viable candidate for the transgenerational transmission trigger of a given acquired trait. It has been reported recently that the higher lifetime entropy generation of a unit's body mass, the higher the entropy stress level (which is a measure of energy released by a unit's organ mass) and the irreversibility within the organ, resulting in faster organ degradation and consequent health problems for the entire biological system. We therefore suggest a new term: "stress entropic load" will reflect the actual energetic cost of an individual's adaptation and may be used to estimate the probability of inducing transgenerational response once characterized or measured.