Ceruloplasmin (ferroxidase) is a protein with copper ions in its structure. It is considered the main copper protein in human plasma. The concentration of this enzyme is tested when there is a suspicion of copper metabolism disorder in the body. What can the test results show? What is the function of ceruloplasmin in the human body?

Ceruloplasmin( ferroxidase ) is a protein belonging to multimeric oxidases, i.e. enzymes containing copper atoms, capable of catalyzing the oxidation of substrates. It is the most important copper-carrying protein in the blood. Ceruloplasmin also plays a role in the metabolism of iron in our body.

Ceruloplasmin - functions

Ceruloplasmin is an enzyme synthesized in the liver. It contains 6 copper atoms in its protein structure. She is responsible for the transport of the said metal. More than 95% of the copper transported in the body is related to ceruloplasmin.

The enzymatic activity of the described protein concerns the conversion of iron 2+ ions into oxidized iron 3+ ions. Thanks to this, it helps in the transport of this element in the body.

The normal concentration of ceruloplasmin in a he althy body is 20-50 mg / dL.

Ceruloplasmin in antioxidant processes

Cerruplasmin apart from the functions related to the transport of copper and the transformation of iron ions, also has the ability to remove superoxide radicals. Jet is a reactive form of oxygen which, if not deactivated, can cause damage to the body.

Ceruloplasmin in oxidative processes

Ceruplasmin is also responsible for carrying out the oxidation reactions. This enzyme activates the oxidation of various complex compounds in the body. This group includes:

  • norepinephrine
  • serotonin
  • sulfhydryl compounds
  • ascorbic acid

When do ceruloplasmin levels drop?

Due to the fact that ceruloplasmin is synthesized in the liver, its concentration in the blood decreases when this organ is disturbed.

Other causes of low blood levels of ceruloplasmin:

  • genetic background
  • low levels of copper in the body associated with malnutrition
  • insufficient absorption of copper from the intestine -Menkes' disease (curly hair disease)
  • Wilson's disease
  • vitamin C overdose
  • nephrotic syndrome

The concentration of ceruloplasmin in the blood depends on the concentration of copper in the body. The form of the enzyme without metal ions is called apoceluroplasmin. It is unstable and decays if copper ions are not attached to it.

When are ceruloplasmin levels too high?

Ceruloplasmin belongs to the so-called acute phase proteins. This means that its level rises in the course of inflammatory processes in the body. Tissue necrosis and chronic inflammation may lead to an increase in the synthesis of this enzyme in the liver.

Higher-than-normal levels of ceruloplasmin occur when:

  • copper poisoning
  • zinc deficiency
  • pregnancy
  • taking oral hormonal contraceptives
  • lymphoma
  • inflammation
  • rheumatoid arthritis
  • angina
  • Alzheimer's disease
  • schizophrenia

Mutations of the gene encoding ceruloplasmin

Mutations in the genetic information for ceruloplasmin are extremely rare. The disease caused by this type of damage is aceruloplasemia. As a result, there is an excessive accumulation of iron in the body.

The accumulation of this metal in the brain leads to characteristic neurological symptoms such as:

  • cerebellar ataxia
  • dementia

Excess iron can also accumulate in the liver, pancreas, and even the retina of the eye. Accumulation of this element can lead to

  • cirrhosis of the liver
  • hormonal disorders
  • vision loss

Ceruloplasmin - Ceruloplasmin level test

This measurement is not a standard test for blood chemistry. The test is performed in the case of suspected copper metabolism disorders as well as some liver diseases.

Measurement of the concentration of ceruloplasmin in the blood is primarily used to diagnose Wilson's disease. During its course, there is a significant decrease in the level of the enzyme carrying copper in the blood plasma.

In addition to the level of ceruloplasmin, it is usually recommended to measure the concentration of copper in the blood plasma and to determine its content in urine for 24 hours.

The test is usually performed on patients between 20 and 40 years of age who have been diagnosed with cirrhosis or hepatitis of unknown cause. Additional symptoms that are an indication for the measurement:

  • tremors of the upper limbs
  • drooling
  • appetite disorders
  • difficulties in moving
  • communication disorders
  • balance problems

Why does ceruloplasmin drop during Wilson's disease?

Wilson's disease is closely related to insufficient synthesis of ceruloplasmin from apoceruloplasmin in the body. The disorder is genetic.

During the disease, the concentration of copper in the body increases. It is related to the disturbance of the transport of copper. As a result, copper does not bind properly to the transport protein.

In a he althy organism, the excess of the element is excreted with bile in the form of ceruloplasmin. This process is disturbed in Wilson's disease sufferers.

This is due to the impairment of ceruloplasmin synthesis from apoceruloplasmin in hepatocytes. The reason for this is a defect in the protein that supplies this element to the liver cells.

Copper does not reach apoceruloplasmin in hepatocytes, while accumulating in the body.

During Wilson's disease, metal ions accumulate unbound in plasma and organs including the liver and brain. The process leads to organ damage through the toxic effects of copper.

Wilson's disease is a congenital disease, but it does not show any obvious symptoms in the first years of life. The dysfunctions usually appear in patients between 10 and 40 years of age. Due to the accumulation of copper in the liver, a large proportion of patients develop cirrhosis or liver inflammation.

Most patients with Wilson's disease develop neuropsychiatric disorders. They are related to the accumulation of copper in the brain. The most common nervous system symptoms are:

  • mood disorders
  • personality disorders
  • cognitive impairment
  • psychotic symptoms

Due to the non-specificity of symptoms, Wilson's disease is incorrectly diagnosed as various types of mental disorders, e.g. schizophrenia.

The characteristic symptoms of Wilson's disease are:

  • trembling hands
  • low appetite
  • writing disorder
  • drooling
  • imbalance
  • excessive muscle tension
  • speech disorder
  • swallowing disorders
  • involuntary movements

The presence of these symptoms may be an indication to test the level of ceruloplasmin in the blood.

A very characteristic symptom of Wilson's disease is the appearance of a colored circle on the cornea of ​​the eye. The change is called the Kayser-Fleischer ring. Confirmation of his presence oneye is one of the diagnostic procedures.

About the authorSara Janowska, MA in pharmacyPhD student of interdisciplinary doctoral studies in the field of pharmaceutical and biomedical sciences at the Medical University of Lublin and the Institute of Biotechnology in Białystok. A graduate of pharmaceutical studies at the Medical University of Lublin with a specialization in Plant Medicine. She obtained a master's degree defending a thesis in the field of pharmaceutical botany on the antioxidant properties of extracts obtained from twenty species of mosses. Currently, in his research work, he deals with the synthesis of new anti-cancer substances and the study of their properties on cancer cell lines. For two years she worked as a master of pharmacy in an open pharmacy.

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