Featured Research

from universities, journals, and other organizations

Biomarker for stress hormones in polar bears, wildlife affected by global climate change

Date:
January 24, 2014
Source:
University of Massachusetts at Amherst
Summary:
Researchers have reported fluctuations in climate and ice cover related to stress in polar bears as indicated by levels of cortisol in hair samples.

Chemical analyses by neuroscientist Jerrold Meyer and colleagues at the University of Massachusetts Amherst are helping to establish hair cortisol concentration (HCC) as an important new biomarker for stress in wild animals facing global climate change.

The technique is demonstrated in the current issue of the Journal of Visualized Experiments (JOVE) where Meyer's lab manager Kendra Rosenberg and neuroscience and behavior graduate student Amanda Hamel provide an annotated illustration of UMass Amherst's standard technique, which they hope will lead to its wider use, including in humans.

Last year, an international research team led by Danish bioscientist Thea Bechshψft of Aarhus University reported that fluctuations in climate and ice cover are closely related to stress among polar bears in East Greenland as indicated by levels of the stress hormone cortisol in hair samples measured in Meyer's UMass Amherst laboratory. He says, "We are very hopeful that researchers around the world will discover the usefulness of this type of analysis once they learn that it can now be done with much greater reliably than before."

"Nobody else has done this so far," adds Meyer, a behavioral endocrinologist. "We've not only been one of the key developers of the technique but we have also have worked very hard to demonstrate its reliability and validity. In collaboration with Melinda Novak, chair of the psychology department, we were among the first to show in a major controlled study that a prolonged or major life stress does lead to a demonstrable increase in cortisol in hair. Now we're making the technique available to others and we hope it spurs new collaborations with our lab."

Meyer's assay core laboratory is expert in measuring not only cortisol concentrations, but also progesterone, testosterone and oxytocin levels in a variety of sample types including hair, blood, saliva and cerebrospinal fluid. His major research area is in behavioral endocrinology, and in exploring "how these modern techniques can be used to get exciting new insights into the relationship between the endocrine system and behavior in animal research and human studies."

Over the past 40 years, Meyer says techniques have become not only much more sensitive and precise, but safer for researchers as they have been able to move away from using radioactive substances. "We can now measure much lower levels of substances than we could when I was a grad student," he recalls. "And with new enzyme immunoassay techniques read by a microplate reader, the work has become not only safer for researchers, but for lab workers and the environment."

To analyze cortisol levels in hair, the researchers need a sample about 3 cm long and weighing about 5 mg, that is, 10 or 12 strands. In humans, this amount cut from the scalp outward represents about three months of hormone activity as human hair grows an average 3 cm per month, Meyer notes. In his UMass Amherst lab about six undergraduates are currently learning the exacting techniques for washing and drying samples, grinding them to powder, extracting the cortisol, and conducting the enzyme immunoassay.

For the collaboration with Bechshψft and colleagues, Meyer's lab received blind hair samples from 88 polar bears legally killed between 1988 and 2009 in Greenland by indigenous people who have an arrangement with researchers to provide biological samples. Cortisol will persist in hair for hundreds of years, Meyer explains.

"We have analyzed this hormone in several blind samples of polar bear hair from museum specimens that were killed and stuffed in the late 1800s, and we had no trouble measuring it 125 years later," he says. "Others have measured cortisol concentrations in Peruvian mummies 1,500 years old. It's one of the beauties of hair cortisol, you can measure it in archival specimens."


Story Source:

The above story is based on materials provided by University of Massachusetts at Amherst. Note: Materials may be edited for content and length.


Journal Reference:

  1. Jerrold Meyer, Melinda Novak, Amanda Hamel, Kendra Rosenberg. Extraction and Analysis of Cortisol from Human and Monkey Hair. Journal of Visualized Experiments, 2014; (83) DOI: 10.3791/50882

Cite This Page:

University of Massachusetts at Amherst. "Biomarker for stress hormones in polar bears, wildlife affected by global climate change." ScienceDaily. ScienceDaily, 24 January 2014. <www.sciencedaily.com/releases/2014/01/140124093659.htm>.
University of Massachusetts at Amherst. (2014, January 24). Biomarker for stress hormones in polar bears, wildlife affected by global climate change. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2014/01/140124093659.htm
University of Massachusetts at Amherst. "Biomarker for stress hormones in polar bears, wildlife affected by global climate change." ScienceDaily. www.sciencedaily.com/releases/2014/01/140124093659.htm (accessed September 2, 2014).

Share This




More Earth & Climate News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Iceland Lowers Aviation Alert on Volcano

Iceland Lowers Aviation Alert on Volcano

AFP (Sep. 1, 2014) — Iceland has lowered its aviation alert on its largest volcano after a fresh eruption on a nearby lava field prompted authorities to enforce a flight ban for several hours. Duration: 01:07 Video provided by AFP
Powered by NewsLook.com
Lightning Hurts 3 on NYC Beach

Lightning Hurts 3 on NYC Beach

AP (Sep. 1, 2014) — A lightning strike injured three people on a New York City beach on Sunday. The storms also delayed flights and interrupted play at the US Open tennis tournament. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Thailand Totters Towards Waste Crisis

Thailand Totters Towards Waste Crisis

AFP (Sep. 1, 2014) — Fears are mounting in Bangkok that poor planning and lax law enforcement are tipping Thailand towards a waste crisis. Duration: 01:21 Video provided by AFP
Powered by NewsLook.com
Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Newsy (Sep. 1, 2014) — A study of almost 20 years' worth of satellite images shows Antarctic sea levels are on the rise as ice shelves continue to melt. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins