What is Hashimoto’s Thyroiditis?
The autoimmune condition Hashimoto’s thyroiditis (HT) is a disease where lymphocytes mediate the autoimmune damage and destruction of the thyroid gland.
Inflammation from Hashimoto’s disease, also known as chronic lymphocytic thyroiditis, often leads to an underactive thyroid gland (hypothyroidism). Hashimoto’s disease is the most common cause of hypothyroidism. It primarily affects middle-aged women but can also occur in men and women of any age and in children
Signs of HT can include increased infiltration of lymphocytes into the thyroid, high levels of circulating autoantibodies specific to thyroid antigens and an increase in thyroid size.
These can lead to significant clinical complications in affected patients including diabetes, anemia and a propensity to develop other serious autoimmune conditions. HT affects women more commonly than men.
What are Common Symptoms of HT?
You might not notice signs or symptoms of Hashimoto’s disease at first, or you may notice a swelling at the front of your throat (goiter). Hashimoto’s disease typically progresses slowly over years and causes chronic thyroid damage, leading to a drop in thyroid hormone levels in your blood. The signs and symptoms are mainly those of an underactive thyroid gland (hypothyroidism).
Some common sign and symptoms of HT are:
- Fatigue and sluggishness.
- Increased sensitivity to cold.
- Pale, dry skin.
- Hair loss.
- Unexplained weight gain.
What Causes Hashimoto’s Thyroiditis?
Hashimoto’s disease is an autoimmune disorder in which your immune system creates antibodies against the thyroid gland. The exact cause of why this happens is unknown. Some research suggests that virus or bacterial infection might trigger the response, while other studies suggest that there is a genetic component involved.
The specific molecular mechanisms governing the development of HT are uncertain, although both genetic and environmental factors are thought to contribute, leading to an eventual loss of self-tolerance allowing for T cells to react to specific thyroid autoantigens.
This is associated with an influx of lymphocytes into the thyroid, as well as an increase in the production of specific anti-thyroid antigen autoantibodies. A key regulator of immune responses to a wide range of antigens are CD4+ T helper (Th) cells. Interleukin 17 (IL-17) producing Th17 subset of CD4+ cells is known to be linked to the development of autoimmune conditions including HT. Whereas levels of the immunosuppressive regulatory T cells (Tregs) are associated with reductions in such autoimmunity.
Patients with HT have been shown to have high levels of Th17 cells within the thyroid, as well as increased levels of Th17-derived cytokines including IL-22 and IL-17 relative to normal controls (individuals without the condition).
What are Risk Factors For Developing HT?
- Sex. Women are much more likely to get Hashimoto’s disease.
- Age. Hashimoto’s disease can occur at any age but more commonly occurs during middle age.
- Heredity. You have a higher risk of HT if others in your family have thyroid or other autoimmune diseases.
- Other autoimmune diseases. Having another autoimmune disease, such as rheumatoid arthritis, type 1 diabetes or lupus, increases your risk of developing Hashimoto’s disease.
- Radiation exposure. People exposed to excessive levels of environmental radiation are more prone to Hashimoto’s disease.
Current Treatment Options
One of the more commonly used treatments is the use of synthetic hormones to replace thyroid hormone. This usually involves daily use of the synthetic thyroid hormone levothyroxine (Lexoxyl, Synthroid, others).
There are currently no effective means of treating HT, with the primary strategies of thyroid hormone therapy, surgery or immunomodulatory therapy being associated with serious risks and side effects. Thus, there is an urgent need to identify novel treatments for the condition. Researchers have been studying the use of mesenchymal stem cells (MSCs) due to their immunomodulatory potential that makes them useful in treating immune related diseases.
A group of researchers from the University of Traditional Chinese Medicine in Nantong, China published in 2019 a study in which they utilized female rats with induced HT to evaluate the ability of transplanted MSCs to regulate Th17/Treg interactions. They found that transplanted MSCs could decrease thyroid lesions and less lymphoid infiltration of the thyroid in MSC-treated rats relative to HT model rats, as well as fewer Th17 cells and more Treg cells.
The researchers used MSCs derived from human umbilical cord tissue and infused them intravenously (IV) on days 0, 7, 14 and 21 and compared them with controls that did not receive the infusion. They found that the treatment with MSCs decreased the thyroid lesions and lymphoid infiltration. They also observed decreased levels of autoantibodies against thyroid peroxidase and thyroglobulin compared to healthy controls.
Future trials in humans will be needed to explore the underlying molecular mechanisms of how MSCs influence HT pathogenesis. The results suggest MSCs can reduce thyroid autoantibody levels in a rat model. If the results can be translated in the future into human trials, cellular therapies could become an appropriate and novel treatment for Hashimoto’s thyroiditis.
Stem Cell Therapy with Umbilical Cord MSCs at Zignagenix
Mesenchymal stem cells have the ability to modulate the immune system. Due to the nature of this condition and how it’s caused by a dysregulation in the immune system, MSCs are an excellent treatment option that has been under study and has shown good results.
At our clinic we use Umbilical cord-derived MSCs that are infused intravenously at high doses and are combined with exosome therapy to increase the quantity and immunomodulatory effect of stem cells.
Hashimoto’s thyroiditis is known to have an increased activity of T cell lymphocytes that MSCs have shown to be capable of decreasing this activity, decreasing the levels of autoantibodies and the lymphoid infiltration on the thyroid gland, improving the patient’s symptoms and their quality of life.
Cao, Y., Jin, X., Sun, Y., & Wen, W. (2019). Therapeutic effect of mesenchymal stem cell on Hashimoto’s thyroiditis in a rat model by modulating Th17/Treg cell balance. Autoimmunity, 1–11. doi:10.1080/08916934.2019.1697689