$16 Every disease is a consequence of the second principle of thermodynamics

Cells have to release entropy in order to keep their structural integrity. They can export entropy either in the form of heat (catabolism) or in the form of biomass (anabolism). Biomass can be exported outside the cell in the form of the extracellular secretion of molecules. The secreted molecules can be released in the blood and absorbed by other cells. Some of these molecules have special signaling properties and modify the activity of the cell which ingest it. For example estrogens are secreted by the ovaries and transported by the blood stream. These hormones bind to specific receptors in the breast and induce the growth of the gland at puberty. Similarly, brain glial cells release lactate as a byproduct of glucose they can not burn completely. There is an uptake of lactate by adjacent neurons which burn it and release entropy outside the body in the form of heat.

Biomass can also stay inside the cell. Stem cells release their entropy in the form of a daughter cell. The division of the cell in two different entities increases the entropy of the tissue.

Most common diseases (if not all) and conditions can be understood by the modulation of entropy secreted by the cell. As of today, symptoms and affected sites allow classification of diseases. We will try to classify the pathologies by the typologies of entropy.

Diseases with change in global entropy production

In a few rare diseases, the total amount of entropy can be increased or lowered. During hyperthyroidism there is increased heart rate, weight loss, diarrhea, nervousness, irritability, perspiration and hand tremors. There is an increased metabolism and enhanced mitochondrial activity resulting in enhanced production of entropy. Similar symptoms occur during substance abuse. Cocaine or heroin increase the heart rate, respiration and result in euphoria. Entropy is increased.
Carhart-Harris, R. L., Leech, R., Hellyer, P. J., Shanahan, M., Feilding, A., Tagliazucchi, E., Nutt, D. (2014). The entropic brain: a theory of conscious states informed by neuroimaging research with psychedelic drugs. Frontiers in human neuroscience, 8, 20.

To the opposite, during hypothyroidism, there is decreased rate of entropy production. The patients suffer from tiredness, depression and slow heart rate. Abuse of sedative may result in somnolence, amnesia and possibly dementia.

Diseases with increased synthesis of intracellular and extracellular biomass

Some benign tumors secrete proteins that are excreted in the blood stream. Benign prostatic adenoma secretes a protein: Protein Specific Antigen (PSA) that can be measured in the blood stream and used as a diagnostic tool. When present in the blood, this PSA has no known biological function. Other benign tumors can secrete hormones, which can be toxic. Best-known examples are the thyroid adenoma. Some of these benign tumors secrete thyroid hormones that can, in turn, be toxic to the heart or the brain.

Diseases with increased secretion of extracellular biomass and increased temperature

Hyperthermia is present in most acute infections, but also during tissue necrosis (like cardiac infarct). During infection or cell death there is an increased secretion of pro-inflammatory proteins or CRP. During cardiac infarct, release in the blood stream of multiple proteins present in the myocardial cells, such as troponin, occurs. The cardiologist will know the diagnosis of cardiac infarct by measuring the level of troponin in the blood. If it is increased, heart cells have died.

 
Diseases with Increased Heat and Intracellular and Extracellular Biomass

Increased heat and synthesis of biomass are always present in inflammatory diseases.
The following are common types of inflammatory diseases.

Acute Inflammation

Often the inflammatory disease is limited to a specific organ. Arthritis affects the joints, bronchitis the lung. More rarely the inflammation is diffuse and affects different organs. So rheumatoid arthritis can be limited to the joints. But there are more severe forms with pulmonary or cardiac involvement. Among any inflammation, no matter what its extent and gravity is, you have a concomitant release of entropy in the form of secretion of molecules. In other words, there is release of proteins in the blood stream, such as the C-Reactive Proteins (CRP) as well as numerous cytokines and lymphokines. The secretion of these proteins such as lymphokine and cytokine will result in the activation of the immune system. The immune cells will proliferate thus releasing their entropy in the form of new cells. These immune cells will invade diseased tissue and aid in recovery.
 

Table 4: link between diseases

From Schwartz, L., Devin, A., Bouillaud, F., & Henry, M. (2020). Entropy as the Driving Force of Pathogenesis: an Attempt of Diseases Classification Based on the Laws of Physics. Substantia, 4(2).