Navigation Links
Longer-lived rodents have lower levels of thyroid hormone

The 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 deter mined 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.


'"/>

Source:American Physiological Society


Related biology news :

1. Insight into natural cholesterol control suggests novel cholesterol-lowering therapy
2. Medical whistleblowers speak out
3. The evolutionary triumph of flower power
4. Bumblebees copy one another when contending with unfamiliar flowers
5. Analysis of flower genes reveals the fate of an ancient gene duplication
6. Gene therapy to lower blood pressure just enough
7. Long-sought flower-inducing molecule found
8. Divergent mating systems and parental conflict as a barrier to hybridization in flowering plants
9. Reducing antibiotic use lowers rates of drug-resistant bacteria
10. Recreating Flowers for Algernon with a happy ending
11. Overfishing may drive endangered seabird to rely upon lower quality food
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/17/2017)... , April 17, 2017 NXT-ID, Inc. ... company, announces the filing of its 2016 Annual Report on Form ... Exchange Commission. ... Form 10-K is available in the Investor Relations section of the ... on the SEC,s website at http://www.sec.gov . 2016 ...
(Date:4/11/2017)... Research and Markets has announced the addition of the "Global ... ... at a CAGR of 30.37% during the period 2017-2021. ... based on an in-depth market analysis with inputs from industry experts. ... the coming years. The report also includes a discussion of the ...
(Date:4/5/2017)... , April 5, 2017  The Allen Institute ... Allen Cell Explorer: a one-of-a-kind portal and dynamic digital ... 3D imaging data, the first application of deep learning ... human stem cell lines and a growing suite of ... platform for these and future publicly available resources created ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... BioMarketing, a leading provider of patient support solutions, has announced ... network, which will launch this week. The VMS CNEs will ... to enhance the patient care experience by delivering peer-to-peer education ... professionals to help women who have been diagnosed and are ... ...
(Date:10/10/2017)... SAN DIEGO, CALIF. (PRWEB) , ... October 10, 2017 , ... ... website as part of its corporate rebranding initiative announced today. The bold new ... broaden its reach, as the company moves into a significant growth period. , It ...
(Date:10/10/2017)... CRUZ, Calif. , Oct. 10, 2017 ... grant from the NIH to develop RealSeq®-SC (Single Cell), ... kit for profiling small RNAs (including microRNAs) from single ... Analysis Program highlights the need to accelerate development of ... "New techniques for measuring ...
(Date:10/9/2017)... ... 09, 2017 , ... At its national board meeting in North Carolina, ... University’s Departments of Physics and Astronomy, has been selected for membership in ARCS ... for the 2015 Breakthrough Prize in Fundamental physics for the discovery of the accelerating ...
Breaking Biology Technology: