336
Zinc and copper are key to normal hormone synthesis. Zinc is an activator of 200
enzymatic reactions in the body, is required for pituitary gonadotropin, and is
required for testosterone synthesis. Copper acts as a stimulant for several neurotransmitters and is closely related to estrogen. There are correlations between
estrogen dominance and copper toxicity. The mineral iodine is crucial for the synthesis of thyroid hormones. Iodine deficiency is known to play an important role in
some thyroid conditions. Iodine deficiency results in a decrease in the concentration
of T 3 and T 4 .
11.6.2 Minerals and Metabolism
Most scientists single out 13 minerals essential for nutrition. These are minerals
whose constant deficiencies can cause deterioration of the functioning of the organism (disease), which can be prevented and cured by diet, by adequate food, and/or
in a state of severe deficiency, by taking supplements (WHO 2003; Marinangeli and
Jones 2010). There are still some issues regarding other minerals. The functioning
of the mineral elements can be structural, osmotic, catalytic, and signaling.
One specific mechanism is required for the resorption of copper from the gastrointestinal tract because the copper ion (Cu
2+
) is practically insoluble. One unidentified low-molecular-weight substance from human saliva and gastric juice forms a
complex with Cu
2+
that is soluble in the pH of intestinal fluid. In the cells of the
small intestinal mucosa, copper probably binds to a low-molecular-weight metalbinding protein called metallothionein. Copper enters the plasma where it binds to
amino acids, especially histidine, and serum albumin in one place that binds it
tightly. Copper is removed from the circulation by the liver within 1 hour. The liver
processes copper in two ways. The first is that copper is excreted via the bile into the
gastrointestinal tract from which it is not resorbed. The fact is that the homeostasis
of copper is maintained exclusively by this excretion in the bile, i.e., the more copper is excreted, the more it is in the feces. Normally there is only trace copper in
the urine.
Another way of copper metabolism in the liver is its incorporation into ceruloplasmin, a glycoprotein that is synthesized only in the liver. Ceruloplasmin is one of
the copper-dependent ferroxidases. It contains 95% of the total copper plasma.
Ceruloplasmin is not a transport protein for Cu
2+
because the copper from ceruloplasmin does not exchange with the copper ion or copper bound to other molecules.
Ceruloplasmin contains 6–8 copper atoms, half in cupro (Cu
+
) and half in cupra
(Cu
2+
) form.
Ceruloplasmin oxidizes Fe
2+
to Fe
3+
which is necessary for the mechanism of
iron resorption from the gastrointestinal tract. Other copper metalloproteins include
cytochrome oxidase, tyrosinase, monoamine oxidase, superoxide dismutase, and
lysyl oxidase. Boron is very efficiently resorbed and excreted in the urine.
Zinc metabolism is also a very complex process in the human body. Zinc-binding
factor (picolinic acid), which is secreted by the pancreas, is present in the lumen of
V. I. Petropulos and B. Balabanova
Zinc and copper are key to normal hormone synthesis. Zinc is an activator of 200
enzymatic reactions in the body, is required for pituitary gonadotropin, and is
required for testosterone synthesis. Copper acts as a stimulant for several neurotransmitters and is closely related to estrogen. There are correlations between
estrogen dominance and copper toxicity. The mineral iodine is crucial for the synthesis of thyroid hormones. Iodine deficiency is known to play an important role in
some thyroid conditions. Iodine deficiency results in a decrease in the concentration
of T 3 and T 4 .
11.6.2 Minerals and Metabolism
Most scientists single out 13 minerals essential for nutrition. These are minerals
whose constant deficiencies can cause deterioration of the functioning of the organism (disease), which can be prevented and cured by diet, by adequate food, and/or
in a state of severe deficiency, by taking supplements (WHO 2003; Marinangeli and
Jones 2010). There are still some issues regarding other minerals. The functioning
of the mineral elements can be structural, osmotic, catalytic, and signaling.
One specific mechanism is required for the resorption of copper from the gastrointestinal tract because the copper ion (Cu
2+
) is practically insoluble. One unidentified low-molecular-weight substance from human saliva and gastric juice forms a
complex with Cu
2+
that is soluble in the pH of intestinal fluid. In the cells of the
small intestinal mucosa, copper probably binds to a low-molecular-weight metalbinding protein called metallothionein. Copper enters the plasma where it binds to
amino acids, especially histidine, and serum albumin in one place that binds it
tightly. Copper is removed from the circulation by the liver within 1 hour. The liver
processes copper in two ways. The first is that copper is excreted via the bile into the
gastrointestinal tract from which it is not resorbed. The fact is that the homeostasis
of copper is maintained exclusively by this excretion in the bile, i.e., the more copper is excreted, the more it is in the feces. Normally there is only trace copper in
the urine.
Another way of copper metabolism in the liver is its incorporation into ceruloplasmin, a glycoprotein that is synthesized only in the liver. Ceruloplasmin is one of
the copper-dependent ferroxidases. It contains 95% of the total copper plasma.
Ceruloplasmin is not a transport protein for Cu
2+
because the copper from ceruloplasmin does not exchange with the copper ion or copper bound to other molecules.
Ceruloplasmin contains 6–8 copper atoms, half in cupro (Cu
+
) and half in cupra
(Cu
2+
) form.
Ceruloplasmin oxidizes Fe
2+
to Fe
3+
which is necessary for the mechanism of
iron resorption from the gastrointestinal tract. Other copper metalloproteins include
cytochrome oxidase, tyrosinase, monoamine oxidase, superoxide dismutase, and
lysyl oxidase. Boron is very efficiently resorbed and excreted in the urine.
Zinc metabolism is also a very complex process in the human body. Zinc-binding
factor (picolinic acid), which is secreted by the pancreas, is present in the lumen of
V. I. Petropulos and B. Balabanova