 |
|
Longer-lived rodents have lower levels of thyroid hormone
October 10, 2006The thyroid may play an important role in longevity, with longer-lived rodents showing significantly lower levels of a thyroid hormone that speeds metabolism, a new study has found.
The study further strengthens the theory that the faster an animal's metabolism, the shorter its life, and vice versa, said Mario Pinto, the study's lead author. The thyroid releases hormones that regulate metabolic rate.
"Thyroid hormones are key regulators of metabolism and have been widely implicated to influence longevity," the authors wrote. Pinto will present the study "Differential thyroid hormone activity in rodents with different life spans" at a poster session Oct. 9 at Comparative Physiology 2006: Integrating Diversity. The study was carried out by Pinto and Rochelle Buffenstein, City College of New York.
Thyroid key to metabolic rate
The thyroid gland produces thyroxine (T4) which converts to triiodothyronine (T3) in the presence of iodine. T3 is the active component of T4 and is the key hormone in regulating metabolism, Pinto said. When an animal becomes cold, for example, its body converts T4 to T3 to speed metabolism and warm the body, he explained.
"Mice strains that exhibit extended longevity tend to have lower thyroid hormone concentrations than shorter living strains," the authors wrote. "Significant declines in thyroid hormone correlate well with enhanced maximum lifespan."
The study compared the levels of these thyroid hormones among four groups of rodents with different life spans: mice, guinea pigs, Damara mole-rats and naked mole-rats. Mice live to about three and a half years; guinea pigs live to six years; Damara mole-rats to 15 years; and naked mole-rats to 28 years.
The animals were of different ages, but at comparable points in their life spans. For example, the mole-rats, which live 28 years, were two years old. The mice, which live about 3.5 years, were six months old. The study determined the levels of T3 and T4 for each animal.
T4 levels vary the most
T4 levels varied significantly between all of the groups, with the shorter-lived groups having higher levels of T4 than longer-lived groups. The mice, for example, had twice as much T4 as the Damara mole-rats and had and three times more than that of the naked mole-rats, Pinto reported. There was also a significant difference in T3 levels between the naked mole-rats and the guinea pigs, but not between any of the other groups
"These hormone concentration differences correlate with maximum species lifespan and suggest an important regulatory role of thyroid hormone in longevity," the researchers concluded. However, because T3, levels did not differ significantly among all the groups, further research in this area using larger sample sizes (numbers of rodents in each group) is needed, Pinto said.
American Physiological Society
Thyroid key to metabolic rate
The thyroid gland produces thyroxine (T4) which converts to triiodothyronine (T3) in the presence of iodine. T3 is the active component of T4 and is the key hormone in regulating metabolism, Pinto said. When an animal becomes cold, for example, its body converts T4 to T3 to speed metabolism and warm the body, he explained.
"Mice strains that exhibit extended longevity tend to have lower thyroid hormone concentrations than shorter living strains," the authors wrote. "Significant declines in thyroid hormone correlate well with enhanced maximum lifespan."
The study compared the levels of these thyroid hormones among four groups of rodents with different life spans: mice, guinea pigs, Damara mole-rats and naked mole-rats. Mice live to about three and a half years; guinea pigs live to six years; Damara mole-rats to 15 years; and naked mole-rats to 28 years.
The animals were of different ages, but at comparable points in their life spans. For example, the mole-rats, which live 28 years, were two years old. The mice, which live about 3.5 years, were six months old. The study determined the levels of T3 and T4 for each animal.
T4 levels vary the most
T4 levels varied significantly between all of the groups, with the shorter-lived groups having higher levels of T4 than longer-lived groups. The mice, for example, had twice as much T4 as the Damara mole-rats and had and three times more than that of the naked mole-rats, Pinto reported. There was also a significant difference in T3 levels between the naked mole-rats and the guinea pigs, but not between any of the other groups
"These hormone concentration differences correlate with maximum species lifespan and suggest an important regulatory role of thyroid hormone in longevity," the researchers concluded. However, because T3, levels did not differ significantly among all the groups, further research in this area using larger sample sizes (numbers of rodents in each group) is needed, Pinto said.
American Physiological Society
Thyroid Hormone Current Events and Thyroid Hormone News RSSNewly revised guidelines for managing thyroid cancer published in Thyroid journal
The American Thyroid Association has released new, revised Management Guidelines for the diagnosis and treatment of patients with thyroid nodules and thyroid cancer.
New genetic link between cardiac arrhythmias and thyroid dysfunction identified
Genes previously known to be essential to the coordinated, rhythmic electrical activity of cardiac muscle -- a healthy heartbeat -- have now also been found to play a key role in thyroid hormone (TH) biosynthesis, according to Weill Cornell Medical College researchers.
Specific genetic cause of fetal alcohol-related developmental disorders found
Alcohol consumption by pregnant women hinders brain development in their children by interfering with the genetic processes that control thyroid hormone levels in the fetal brain, a new animal study found.
Concern over inappropriate diagnosis and treatment of thyroid problems
More and more people are being inappropriately diagnosed and treated for underactivity of the thyroid gland (known as primary hypothyroidism), warn doctors in an editorial published on bmj.com today.
Smoking during pregnancy may impair thyroid function of mom and fetus
Cigarette smoking during pregnancy is associated with potentially harmful changes in both maternal and fetal thyroid function, according to a new study accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology & Metabolism (JCEM).
Pediatric obesity may alter thyroid function and structure
In addition to its strong associations with hypertension, cardiovascular disease, and diabetes, pediatric obesity may induce alterations in thyroid function and structure, according to a new study accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology & Metabolism (JCEM).
6 environmental research studies reveal critical health risks from plastic
Exposure to Bisphenol A (BPA), phthalates and flame retardants (PBDEs) are strongly associated with adverse health effects on humans and laboratory animals.
Thyrotropin levels associated with Alzheimer's disease risk in women
Women with low or high levels of the hormone thyrotropin, which affects thyroid gland function and thyroid hormone levels, appear to have a higher risk of developing Alzheimer's disease, according to a report in the July 28 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Newly discovered role of thyroid hormone during pregnancy
Thyroid hormone deficiencies in early pregnancy can cause locomotor underdevelopment in the child, according to research from the Swedish medical university Karolinska Institutet. The results bring new insights into brain development and could affect routine pregnancy testing.
Thyroid treatment no 'quick fix' for weight loss in children
Children treated for hypothyroidism aren't likely to drop pounds with treatment for the condition says a new study in the Journal of Pediatrics. The study is the first to examine the link between hypothyroidism treatment and weight loss in pediatric patients.
More Thyroid Hormone Current Events and Thyroid Hormone News Articles
 |
Source Naturals N-Acetyl L-Tyrosine 300mg, 120 tablets by Source Naturals Dietary supplement. N-Acetyl L-Tyrosine is a more rapidly absorbed and bioavailable form of the amino acid L-tyrosine, and is less prone to urinary excretion. L-Tyrosine is converted in the body to key biologic compounds, including epinephrine, dopamine, L-dopa, CoQ10, thyroid hormones, and melanin. The B vitamins pyridoxine (B-6) and folic acid are provided to assist in the conversion process (These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease). Suitable for vegetarians. Contains no yeast, dairy, egg, gluten, soy or wheat. Contains no sugar, starch, preservatives, or artificial color, flavor or fragrance. |
 |
The Thyroid Hormone Breakthrough: Overcoming Sexual and Hormonal Problems at Every Age by Mary J. Shomon (Author) If you're one of the millions of American women suffering from PMS, irregular periods, difficulty getting pregnant, low sex drive, postpartum depression, menopausal symptoms, or many other hormonal problems, what you may not realize is that thyroid disease could be the culprit. The Thyroid Hormone Breakthrough is a holistic guide to identifying and overcoming the connection between hormonal problems and the thyroid, which goes undiagnosed in more than 30 million women in the U.S. alone. It will help you identify and diagnose thyroid problems and offer strategies to cope with the effects that thyroid conditions can have on everything from puberty to menopause, including ways to avoid the pitfalls of decreased sex drive. With information on diet and exercise, conventional and... |
 |
Raw Thyroid Glandular Complex 60 capsules. (from New Zeland bovine no antibiotics, chemicals & no grasslands pesticides) by Premier Nutraceuticals |
 |
Thyroid Hormones and Tests Audio James M. Lowrance (Primary Contributor) |
 |
The Thyroid Sourcebook (5th Edition) (Sourcebooks) by M. Sara Rosenthal (Author) The classic reference guide for living with thyroid disorder--now completely revised and updated The New York Times called this book "an excellent source of information." The Thyroid Sourcebook features patient narratives; information on the complications of hypo- and hyperthyroidism, such as depression, weight gain, thyroid, eye disease, and sleep disorders; the latest on complimentary medicine; and much more. |
 |
Native Remedies Thyroid Assist for Supporting Healthy Thyroid Functioning (50ml) by Native Remedies Thyroid Assist is a 100% safe, non-addictive, natural herbal remedy. Thyroid Assist can be used consistently to safely support health and systemic balance in the endocrine system. Thyroid Assist contains a selection of herbs known for their supportive function in maintaining thyroid health and hormonal balance. Thyroid Assist supports the healthy functioning of the thyroid, thereby helping to maintain balanced metabolism, body temperature, fertility, healthy weight and routine, healthy performance. Use Thyroid Assist to support normal production of thyroid hormone by the pituitary gland; help support healthy thyroid function naturally and support systemic balance in the endocrine system responsible for regulating body temperature, metabolism, fertility and growth. |
 |
3 bottles - Raw Thyroid Glandular Complex 60 capsules. (from New Zeland bovine, no antibiotics, chemicals & no grasslands pesticides) by Premier Nutraceuticals |
 |
The Menopause Thyroid Solution: Overcome Menopause by Solving Your Hidden Thyroid Problems by Mary J. Shomon (Author) From New York Times bestselling author and nationally recognized patient advocate Mary J. Shomon comes a groundbreaking guide to safely managing menopause through a better understanding of and better care for your thyroid. If you're one of the forty million American women struggling through menopause, you probably know all about the symptoms of fatigue, weight gain, and depression. But what you may not know is that the drop in reproductive hormones frequently triggers a thyroid slowdown—a "thyropause"—that can be the main cause for those troublesome symptoms. In fact, you may not even need hormone therapy, wild yam and progesterone creams, or herbs like black cohosh for a symptom-free menopause. What you really need is to begin to pay attention to your thyroid. ... |
|
|
Thyroid Hormones and Tests Audio James M. Lowrance (Primary Contributor) |
 |
Landmark Diagnostics Home TSH Test; Tests Thyroid Stimulating Hormone Levels in Blood by Landmark Diagnostics Landmark/HealthPoint Diagnostics TSH Test is a self collected lab analysis that measures a substance called Thyroid Stimulating Hormone. This test will help you and your doctor id &/or monitor an underactive or overactive thyroid condition. |
| © 2009 BrightSurf.com |