Magnesium is an essential cofactor of over 300 enzymatic reactions of intermediary metabolism. By activating most ATP-dependent enzymes, such as kinases, aminopeptidases, nucleotidases, pyruvate oxidases, phosphatases, glutaminases, and carboxypeptidases, the mineral is involved in numerous metabolic processes, including oxidative phosphorylation, glycolysis, and protein and nucleic acid synthesis. Magnesium is a component of the following extracellular processes (free extracellular magnesium).
- Neuromuscular excitation conduction and transmission – by competitively displacing calcium ions from receptors and binding sites as a physiological calcium antagonist, magnesium inhibits calcium influx into smooth muscle cells and thus prevents intracellular binding of calcium to troponin; the result is a reduction in muscle contraction or excitability of muscles and nerves and a consequent decrease in energy expenditure and vascular tone.
- Stabilization of biological membranes – through interactions with phospholipids, magnesium lowers membrane fluidity and maintains membrane permeability
- Influencing cell adhesion via magnesium-dependent integrins – integrins are a group of receptors that enable cell adhesion and maintain contact between cells
- Platelet aggregation (aggregation) of platelets) – increased platelet aggregation can lead to the formation of a thrombus (blood clot) and thus thrombosis or embolism blood vessel occlusion).
- Modulation of ion pumps or channels – for example, magnesium affects the NMDH (N-methyl-D-aspartate) receptor channel by blocking it when unopened.
- Regulation of potassium channels in cardiac muscle cellsMaintenance of electrical potential of nerve and muscle membranes normal synaptic transmission of action potentials in neurons.
Magnesium is a component of the following intracellular processes – free intracellular and cytosolic magnesium, respectively.
- Energy production and provision – as a bound element to ATP, magnesium facilitates the cleavage of energy-rich phosphate residues from ATP; in addition, the essential mineral is involved in the degradation of energy-providing macronutrients by oxidation, such as carbohydrates, proteins, fats, and glucose
- Muscle contraction – as an antagonist of calcium, magnesium decreases the contraction of smooth and striated muscle cells, ultimately reducing energy expenditure and vascular tone
- Storage and release of hormones and neurotransmitters – magnesium inhibits both parathyroid hormone function and the release of epinephrine and norepinephrine; because of the reduction in the release of epinephrine and norepinephrine, magnesium may also be referred to as a “stress mineral”; as serum magnesium levels decrease, sensitivity to stress, particularly noise stress, increases as a result of the increased release of the stress hormones epinephrine and norepinephrine; accordingly, magnesium deficiencies may lead to stress-induced physiological damage
- Mineralization and growth of bone – Approximately 50-60% of the magnesium found in the body is stored or deposited in bone tissue and teeth. In this process, magnesium is bound to hydroxyapatite (calcium phosphate salts of high hardness). Magnesium is important for the mineralization of bones and teeth.