Micronutrients
Chuong Pham-Huy, Bruno Pham Huy in Food and Lifestyle in Health and Disease, 2022
The other physiological role of thyroid hormones is to control several metabolic processes in the body. These include the metabolism of carbohydrate, fat, protein, vitamin, and mineral. For example, thyroid hormone increases energy production, increases lipolysis, and regulates neo-glucogenesis, and glycolysis (3). Moreover, thyroid hormones are used to stimulate enzyme synthesis, oxygen consumption, basal metabolic rate, and a wide variety of other physiological activities such as heart rate and respiratory rate (4). However, under different circumstances, excess iodine intake can cause hyperthyroidism (thyrotoxicosis) and toxic nodular goiter (4, 8). Hyperthyroidism is largely confined to people over 40 years of age. Symptoms of hyperthyroidism include palpitations, trembling, nervousness, weight loss, lack of sleep, tremor, high blood pressure, excessive sweating, and heat intolerance (4). Indeed, too little or too much iodine in the body can cause goiter, an enlargement of the thyroid gland.
Hypothyroidism
K. Gupta, P. Carmichael, A. Zumla in 100 Short Cases for the MRCP, 2020
I he common causes of hypothyroidism are: Chronic autoimmune thyroiditis (Hashimoto's thyroiditis).Post surgical resection or radio-iodine therapy for hyperthyroidism.Secondary to anti-thyroid drugs, e.g. carbimazole, etc. Other causes include: Diet with endemic goitre.Developmental abnormalities, e.g. agenesis and maldevelopment.Dyshormonogenesis.Hypopituitarism.
The twentieth century
Michael J. O’Dowd in The History of Medications for Women, 2020
The incidence of hyperthyroidism in pregnant women was in the order of 0.2%. In the majority of patients, the thyrotoxicosis pre-dated pregnancy. In hyperthyroidism there is failure of ovulation and it was only with anti-thyroid therapy that affected women became fertile and eventually pregnant. Treatment of active thyrotoxicosis in pregnancy is imperative because the condition gives rise to higher incidences of toxemia, premature labor, and congestive heart failure. Perinatal mortality and morbidity were also significantly increased in the offspring of untreated patients. Antithyroid drugs for the treatment of hyperthyroidism in pregnancy were introduced by E.B. Astwood in 1951 (Sugrue and Drury, 1980) and Carbimazole or methimazole have been the mainstay of treatment. Antithyroid drugs readily cross the placenta and in high doses can produce neonatal hypothyroidism and goiter.
Thyrotoxic periodic paralysis: a presentation of hyperthyroidism increasing in frequency around the world
Published in Journal of Endocrinology, Metabolism and Diabetes of South Africa, 2023
Periodic paralysis should be considered in patients with sudden-onset paralysis and hypokalaemia. Thyrotoxicosis is a rare form of acquired periodic paralysis that is no longer confined to Asian populations due to global expansion. Clinicians should have a high index of suspicion for this diagnosis as the signs and symptoms of thyrotoxicosis are often subtle. If left untreated, hypokalaemia is likely to recur and may result in grave cardiac arrythmias. Treatment includes potassium supplementation and the use of non-selective beta blockers, such as propranolol. Definitive treatment remains the management of the underlying hyperthyroidism. Due to the potassium shift and no true potassium losses, regular serum potassium levels should be checked during supplementation to avoid rebound hyperkalaemia. Clinicians should also guard against aggressive potassium supplementation. With the expansion of globalisation, clinicians are more likely to encounter thyrotoxic periodic paralysis in all corners of the globe; awareness of this condition is thus imperative.
l -Thyroxine induces left ventricular remodeling and fibrosis in rats by upregulating miR-21 in a reactive oxygen-dependent mechanism: a protective role of N-acetylcysteine
Published in Drug and Chemical Toxicology, 2022
Administration of l-Thy remains the best strategy to induced hyperthyroidism and cardiac dysfunction and remodeling in rodents (Razvi et al.2018, Mayyas et al.2019, Sheng et al.2020). In this study, we validate our animal models by the significant reduction in rats' body weights, impaired LV function and structure, increase heart mass, and increased cardiac collagen deposition. Indeed, hyperthyroidism is associated with weight loss due to suppression of the appetite and increasing the cellular metabolic rate (Zamoner et al.2007, Asker et al.2015, Mayyas et al.2019, Sheng et al.2020). Supporting our data, many other authors have also similar cardiac effects to those reported in this study after subchronic and chronic administration of l-Thy (Wang et al.2010, Weltman et al.2012, Asker et al.2015, Wu et al.2017, Mayyas et al.2019, Barreto-Chaves et al.2020).
Comparing the effects of Portulaca oleracea seed hydro-alcoholic extract, valsartan, and vitamin E on hemodynamic changes, oxidative stress parameters and cardiac hypertrophy in thyrotoxic rats
Published in Drug and Chemical Toxicology, 2022
Roghayeh Pakdel, Mehran Vatanchian, Saeed Niazmand, Farimah Beheshti, Maryam Rahimi, Azita Aghaee, Mousa-Al-Reza Hadjzadeh
There is a close relationship between thyroid hormones and cardiac function. Most of the signs and symptoms of thyroid diseases are because of effects of thyroid hormone action on the cardiovascular system (Razvi et al.2018). Several studies have shown that increased thyroid hormone levels are associated with an increase in cardiac output, cardiac hypertrophy, and a decrease in peripheral vascular resistance. Cardiovascular manifestations of hyperthyroidism include tachycardia, atrial fibrillation, hypertension, widened pulse pressure, cardiac hypertrophy, and even heart failure (Vargas-Uricoechea et al.2014). Thyroid hormones, thyroxine (T4) and triiodothyronine (T3), impinge upon the cardiovascular system directly at the cellular level and indirectly through the hormonal and/or nervous system (Danzi and Klein 2014).
Related Knowledge Centers
- Heat Intolerance
- Tachycardia
- Thyroid Hormones
- Tremor
- Weight Loss
- Diarrhea
- Thyroid
- Pregnancy
- Goitre
- Thyroid Storm