Cortisol plays an important role in normal foetal development and, later in life, in retaining normal body functions during periods of stress. Less research has been carried out on the effects of POPs on cortisol levels than on sex hormones.
POPs are widespread in nature and all animals and humans are exposed to them daily, mainly through food. There have been great concerns regarding the potential ability of these pollutants to affect the body's hormone balance. Zimmer's thesis sheds light on how exposure during early life stages interferes with hormone levels and may therefore cause harm to health later in life. Zimmer also investigated how the production of hormones such as cortisol and sex hormones were affected by environmental mixtures of POPs extracted from fish.
The thesis reveals that exposure to PCBs during foetal life and the suckling period caused altered cortisol levels in the blood of both foetuses and adult animals. This indicates that exposure during these sensitive, initial stages of life may have long-term consequences. Her findings are important because altered cortisol balance during early life may lead to a predisposition to develop several diseases in adulthood, such as diabetes and cardiovascular diseases.
Knowledge about how POPs work and how different POPs act together is important for the assessment of human health risks. Zimmer used human hormone-producing cells in her study. High levels of brominated flame retardants in a POP mixture extracted from fish in Lake Mjøsa in Norway did not make this mixture more potent as regards increasing hormone synthesis than a similar fish mixture from another lake with considerably lower levels. Another POP mixture extracted from crude, unprocessed cod liver also had a pronounced affect on the synthesis of cortisol and sex hormones, whereas a mixture from processed, commercial cod liver oil, which is frequently consumed as a dietary supplement, was shown to have only limited effects.
Karin Zimmer concludes that cortisol synthesis appears to be a sensitive target for POPs and that efforts should be made to find out to what degree this may threaten human and animal health.
Karin Zimmer Cand.med.vet. defended her thesis entitled “Persistent organic pollutants as endocrine disruptors: effects on adrenal development and steroidogenesis” at The Norwegian School of Veterinary Science on 2nd December 2010.
Credit: Gunn C. Østby
Magnhild Jenssen | alfa
Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
15.12.2017 | Power and Electrical Engineering
15.12.2017 | Materials Sciences
15.12.2017 | Life Sciences