Tag: Selenoprotein P

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Selenium Supplementation and Alzheimer’s Disease

Clinical studies show a clear correlation between Alzheimer’s Disease and low selenium status.  Lower selenium status is associated with worse cognitive decline [Aaseth 2016].

In many regions of Europe and the Middle East, there is poor selenium content in the soil and, accordingly, lower intake of selenium from food sources [Stoffaneller & Morse 2015; Winther 2020].

Woman with Alzheimer's
Adequate levels of selenium are essential for brain function; in fact, the brain is one of the organs that is supplied with selenium at the expense of other organs and tissues in times of low selenium intake. Selenoprotein P plays a special role in delivering selenium to the brain and the neurons. Some of the glutathione peroxidase and thioredoxin reductase selenoenzymes are important intracellular antioxidants in neurons and glia cells of the central nervous system.

The daily intake of selenium from food in many European countries is well below the amount needed for optimal function of important selenoproteins. The needed intake of selenium from food is  estimated to be at least 105 mcg per day [Winther 2020, fig. 2].

Using evidence from human studies in various countries, Prof. Jan Aaseth and colleagues have documented the association between lower selenium  status and Alzheimer’s Disease and/or cognitive impairment [Aaseth 2016]. read more

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Breast Cancer Recurrence and Selenoprotein P Autoimmunity

Breast cancer prognosis is especially poor in patients with low serum selenium and serum selenoprotein P concentrations. Now, researchers have discovered natural autoantibodies with antagonistic properties to selenoprotein P uptake in breast cancer patients and  in patients with thyroid disease [Demircan 2022; Sun 2022].

Autoimmunity
Autoimmunity is the production of antibodies against the tissues or substances of one’s own body, resulting in an autoimmune disease or hypersensitivity reaction. Autoantibodies to Selenoprotein P impair the transport of the essential trace element selenium in breast cancer patients and in Hashimoto’s thyroiditis patients.

Selenium is an essential trace element that has numerous biological functions in the body, most of which are carried out by selenium-containing selenoproteins. Among the more important selenoproteins are selenoprotein P, the main transporter of selenium in the blood, and glutathione peroxidase 3 (GPX3), an important antioxidant.

The human body does not synthesize selenium. Human cells are dependent upon selenium sources in the diet. Unfortunately, the selenium content in the soil and in food varies considerably from region to region in the world. For example, the plasma selenium concentrations in people living in much of Europe are generally below, often well below, 80–90 mcg/L whereas people living in North America generally have plasma selenium levels above 120 mcg/L [Alehagen 2022]. read more

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Selenium Exposure Studies

Selenium exposure in the diet and in supplements: in this review article, we summarize the key outcomes of the best selenium exposure studies.

Optimal Selenium Intake and Status

In his review of the available research literature, Professor Urban Alehagen, Linköping University, Sweden, concluded that a daily intake of 100–150 mcg of selenium per day is required.

This is the intake level that enables an optimal expression of the important selenoprotein P that transports selenium from the liver to peripheral tissues [Alehagen 2022].  For other selenoproteins to be optimized, i.e., to be fully expressed, Prof. Alehagen argues that selenium status of approximately 120 mcg/L when measured in red blood cells is necessary [Alehagen 2022]. read more

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Hashimoto’s Disease Patients Benefit from Selenium Supplementation

Hypothyroidism is the medical condition caused by an underactive thyroid gland that is not producing sufficient quantities of thyroid hormones. It is the failure of the thyroid gland to function normally.

Jan Olav Aaseth
Endocrinologist Jan Aaseth, M.D., Ph. D., ERT, explains that, in Norway, the diagnosis of Hashimoto’s disease is made after a clinical examination that involves determination of the patient’s circulating levels of the thyroid hormone thyroxine (T4), thyroid stimulating hormone, and thyroperoxidase antibodies [Aaseth 2022].
The most common form of hypothyroidism is related to Hashimoto’s disease. Hashimoto’s disease is an autoimmune disorder most common among middle-aged women. Symptoms include anxiety, dry skin, fatigue and lethargy, muscle aches and muscle stiffness, negative mood, sensitivity to cold, slow thinking and poor memory.

The standard treatment for Hashimoto’s disease is twofold:

1) treatment with a synthetic hormone called levothyroxine, which works like the T4 hormone that is naturally produced by the thyroid gland read more

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Serum Selenium Levels Predict Breast Cancer Prognosis

Research done in southern Sweden shows that three blood biomarkers of selenium availability correlated inversely with mortality from breast cancer. The lower the three selenium biomarker levels, the higher the mortality [Demircan 2021].

Breast cancer awareness
Assessment of selenium status at the time of breast cancer diagnosis identifies patients at exceptionally high risk for a poor prognosis. They are breast cancer patients with low levels of selenium, selenoprotein P, and glutathione peroxidase in their blood.

The blood biomarkers are:

  • Total selenium
  • Selenoprotein P
  • Glutathione peroxidase 3

Breast cancer patients with blood concentrations of these three selenium biomarkers in the highest quintile had significantly better chances of survival compared with patients whose blood levels of these substances were in the lowest quintile [Demircan 2021].

Breast cancer patients with low selenium status according to these three biomarkers had the highest mortality risk with an overall survival probability of approximately 50% after 8 years. The difference in survival between the breast cancer patients in the lowest selenium quintile compared to breast cancer patients with at least one biomarker in the highest quintile was especially notable [Demircan 2021]. read more

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Selenium Status and Covid-19 Patients

In cases of severe Covid-19 disease, patients have significantly lower concentrations of selenium and selenoprotein P and significantly higher levels of oxidative stress. That is to say, there is a more intense formation of harmful free radicals in patients with severe Covid-19 disease [Skesters 2022].

Corona virus
An adequate supply of selenium and zinc and vitamin D is essential for resistance to the corona viruses and to other viral infections. Here, Skesters er al show that Covid-19 patients have significantly lower levels of plasma selenium and selenoprotein P and significantly higher levels of oxidative stress.

Note: Oxidative stress is the bio-medical term for an imbalance between harmful free radical activity and protective antioxidant activity. Selenium is a key component of antioxidant selenoproteins such as the glutathione peroxidases and the thioredoxin reductases.

Role of Selenium and Selenoprotein P in Covid-19 Disease

Researchers have been investigating the role that selenium may play in reducing the severity and mortality of Covid-19 infections. Studies have shown a close relationship between low selenium status, Selenoprotein P deficiency, oxidative stress level, and Covid-19 disease incidence, severity, and prognosis [Skesters 2022]. read more