The article entitled “The Extrathyronine Actions of Iodine as Antioxidant, Apoptotic, and Differentiation Factor in Various Tissues,” published in Thyroid in August 2013. This article focuses on extra thyroid activities of iodine.
In the WCT, carried out by Carmen Aceves, Brenda Anguiano, and Guadalupe Delgado, the authors consider diverse biological actions of iodine, especially those as an antioxidant, an apoptosis-inducing factor or tissue differentiation factor in iodine-rich tissues like the mammary and prostate glands.
Aceves C. in their study on molecular iodine published in the International Journal of Molecular Sciences discusses iodine's extrathyroidal effects and its role in immune support and cancer treatment.
Molecular Iodine's Role Beyond Thyroid Hormone Synthesis
Iodine is most associated with the production of thyroid hormones that control the rate of metabolism and other body systems, this paper, unlike the above-mentioned, presents more iodine as an iodine in order to operate more specifically in tissues not associated with the thyroid gland.
This study points out that iodine, especially in its various chemical forms such as molecular iodine (I2), iodide (I−), and iodate (IO3−), acts as an antioxidant, inhibits tumor growth, and enhances cellular differentiation. This bears great importance as additional avenues of therapy for several ailments such as cancer could be developed from the research, which investigates the use of iodine for human health.
Key Findings
The authors examine the fact that iodine, besides its involvement in the synthesis of thyroid hormones, may also be used as an antioxidant and an antiproliferative agent. Iodine plays a crucial role in preventing iodine deficiency disorders and has extrathyroidal benefits, including maintaining organ integrity and potentially suppressing tumor development.
Molecular iodine (I2) has been reported to inhibit growth and decrease size of different tissues, benign and malignant tumors. The study describes that in a different manner, how iodine has such effects. For example:
Antioxidant Effects in Breast Cancer Patients
Iodine also has the ability to eliminate reactive oxygen species (ROS), the products of cellular metabolism that are more toxic to cells than beneficial, doing this in order to prevent a cell from oxidative damage.
Oxidized iodine dissipates the mitochondrial membrane potential, leading to mitochondria-mediated apoptosis, which is a key mechanism in its antioxidant effects. This antioxidant effect is important especially in the tissues that absorb large amounts of iodine like the mother gland and prostate.
Apoptotic Effects: Triggering Mitochondrial Mediated Apoptosis
When present at high enough concentrations, molecular iodine (I2) activates apoptosis (programmed cell death) in cancerous cells via disrupting the mitochondrial membrane potential. Potassium iodide (KI), in comparison, acts as an antioxidant, reducing lipid peroxidation and cellular damage.
This process is carried out by the formation of iodolipids and activation of peroxisome proliferator-activated receptors, especially PPARγ. These processes prevent the proliferation and survival of neoplastic cells.
Differentiation Effects
Iodine on the other hand helps promote normal cellular differentiation, which in turn may thwart certain forms of cancer especially thyroid or mammary tissues.
Treatments with iodine result in significantly elevated levels of specific compounds in cancerous tissues compared to normal mammary tissue, emphasizing iodine's differential effects on cancerous cells vs. non-cancerous cells.
Iodine assists with the help of these alterations in critical signaling proportions along with factors involved in tumor growth and spread to preserve underlying tissues structure and functions.
Iodine Deficiency and Health Risks
Iodine deficiency is a significant public health concern worldwide, leading to a myriad of health problems. When the body lacks sufficient iodine, it can result in thyroid dysfunctions such as goiter, hypothyroidism, and cretinism. These conditions arise because iodine is a critical component in the synthesis of thyroid hormones, which regulate metabolism and other vital bodily functions.
Moreover, iodine deficiency is a major risk factor for thyroid cancer, particularly follicular thyroid cancer. The lack of iodine can also increase the risk of breast cancer, as it induces changes in breast tissue, making it more susceptible to malignancies. This is particularly concerning for breast cancer patients, as adequate iodine levels are crucial for maintaining healthy breast tissue.
Children are especially vulnerable to the effects of iodine deficiency. Insufficient iodine during developmental stages can lead to cognitive and physical impairments, affecting their overall growth and development. In men, chronic iodine deficiency has been linked to an increased risk of benign prostatic hyperplasia (BPH), a condition characterized by the enlargement of the prostate gland.
Iodine Deficiency Disorders
Other health issues associated with iodine deficiency include fatigue, weight gain, and skin problems. These symptoms highlight the essential role of iodine in maintaining overall health and well-being.
Preventing iodine deficiency is achievable through adequate iodine intake. The recommended daily intake of iodine varies by age and gender, but for adults, it is generally 150 mcg/day. Iodine can be obtained from dietary sources such as iodized salt, dairy products, and seaweed, as well as through supplements.
In regions where iodine deficiency is prevalent, public health programs have been established to provide iodine to deficient populations. For instance, in Japan, where iodine intake is high due to the consumption of seaweed, the incidence of breast and prostate cancer is lower compared to Western countries. This underscores the importance of dietary iodine in cancer prevention.
Molecular Iodine
Molecular iodine (I2) supplementation has shown promising results in breast cancer patients, including reducing the expression of vascular endothelial growth factor (VEGF) and triggering mitochondrial-mediated apoptosis. These findings suggest that adequate iodine intake can prevent iodine deficiency disorders and support overall health.
In conclusion, iodine deficiency poses significant health risks, including thyroid dysfunction, breast cancer, and cognitive impairments. Ensuring adequate iodine intake is essential to prevent these health issues, and public health initiatives should focus on providing sufficient iodine to at-risk populations.
Clinical Implications
Based on their review, some of the patients can be recommended to increase their iodine intake (especially I2) to at least 3 mg/day but only under medical supervision.
Iodine is crucial in preventing iodine deficiency disorders and has significant extrathyroidal benefits, including acting as an antioxidant and differentiation agent that maintains organ integrity and potentially suppresses tumor development.
It is recommended for many patients, since evidence is accumulating that iodine is effective in preventing the incidence and recurrence of both benign and malignant neoplasms and is necessary to preserve an adequate iodine pool in the tissues that are capable of iodine uptake.
Conclusion
The study mentions that iodine, particularly in molecular form has numerous benefits outside of the thyroid such as the antioxidant effect, the promoting of apoptosis and differentiation. Adequate iodine intake is crucial in preventing iodine deficient disorders and supporting overall health.
Therefore, they suggest further analysis concerning the role of iodine in the human body activities and development of therapy considering iodine use in the treatment of different diseases especially cancers of prostatic gland.
The authors advocate for more investigations to be carried out explaining better the indications of iodine and that iodine usage in healthcare should not be cast aside.
References
- Aceves, C., Anguiano, B., & Delgado, G. (2013). The Extrathyronine Actions of Iodine as Antioxidant, Apoptotic, and Differentiation Factor in Various Tissues. Thyroid, 23(8), 938–946. https://doi.org/10.1089/thy.2012.0579
