Extracellular pH and the SARS-CoV-2

The normal metabolic processes taking place inside our body lead to continuous variations in pH in a continuous following of intake-elimination of “acids” and bases” that lead to changes in the hydrogen ion concentration with the consequent modification in the organism’s pH, which then needs to adapt to these changes and maintain the physiological pH. The extracellular fluid pH, found in blood’s plasma, is normally strictly regulated between 7.32 and 7.42 by the buffer systems, by the respiratory system and by the renal system

In the last decades, many studies have shown the extracellular pH’s effects on the on cellular and humoral immune function. Since acidic pH predominates at inflammation points and other sites of immune activity, so far most studies have focused on the effect of acidic rather than alkaline pH. Investigations on specific leukocytes mainly demonstrate the inhibition of chemotaxis, respiratory activity and bactericidal capacity at reduced pH. Evidence of altered cytotoxicity and lymphocyte proliferation at acidic pH is also beginning to emerge. Many of the clinical acidoses are accompanied by immunodeficiency. A small number of studies demonstrate acid-induced activation of complement proteins and the alternative complement pathway, as well as increased binding of antibodies to leukocytes at lowered pH.  

Recent studies have shown the great impact of extracellular pH changes on the SARS-CoV-2 infections and the severity of COVID-19 symptoms. The acidic extracellular pH increases the SARS-CoV-2 infection, health complications and the death risk by COVID-19. The extracellular pH’s regulations help prevent or limit the entrance of SARS-CoV-2 in the human cells. In this context, the physiological capacity of the organism to maintain the pH of the extracellular fluid between 7.32 and 7.42 is very important and it is strictly regulated by the buffer systems, the respiratory system and by the renal system

Modulating a more alkaline extracellular environment unsuitable for fusion between the SARS- CoV-2 virus envelope and the host cell membrane is a promising method for preventing or limiting the coronavirus entry into human cells. Recent research has shown, as in past studies performed for other viruses, that a more alkaline extracellular environment could contribute in reducing the life cycle of the SARS- CoV-2 virus and be an excellent ally to current clinical treatments.  

As previously mentioned, the respiratory and renal functions and the body's buffer systems interact with each other to control the pH of organic liquids with extreme precision; when the buffers are saturated or altered, or there is respiratory or renal damage, the pH exceeds these limits causing the onset of acidosis symptoms. Temporary fluctuations in pH are frequent and in most cases are quickly recovered but, if the situation that caused the disturbance persists, the pH can remain altered. 

There are many causes that determine a condition of imbalance of the acid-base system: the most serious concern pathological conditions for example some pathologies of the SNC involving respiratory and circulatory reflexes, but there are others that belong to daily life and that can expose to this condition, which include stress and alcohol, intense sports, smoking, sedentary life, insufficient intake of liquids, prolonged use of drugs, excess of acidifying foods with positive PRAL and other conditions

In the long run, a diet rich in foods with a positive PRAL influences the acid / base characteristics of blood, particularly for patients suffering from functional disorders, pathologies or overweight. For this reason, many diseases benefit from a negative PRAL diet, rich in vegetables, low in sodium (NaCl) and enhanced with buffer systems

The efficacy in using buffer food supplements, to support the regulation of extracellular pH is demonstrated by scientific literature, which has analyzed the benefits of such substances in various fields from sport to both acute and chronic pathological conditions. Melcalin Base, for example, is a buffer supplement containing, in addition to the sodium carbonate buffer, magnesium and calcium and, therefore, it acts as a support to increased excretion of calcium and magnesium, typically seen in conditions of increased net acid excretion (elevated NEA).

Author: Dario Boschiero - Date: 01/02/2022

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