Navigation Links
Estrogen linked to lowered immunity in fish
Date:6/3/2009

Exposure to estrogen reduces production of immune-related proteins in fish. This suggests that certain compounds, known as endocrine disruptors, may make fish more susceptible to disease.

The research may provide new clues for why intersex fish, fish kills and fish lesions often occur together in the Shenandoah and Potomac rivers. The tests were conducted in a lab by scientists from the U.S. Geological Survey.

The study, led by USGS genomics researcher Dr. Laura Robertson, revealed that largemouth bass injected with estrogen produced lowered levels of hepcidin, an important iron-regulating hormone in mammals that is also found in fish and amphibians. This is the first published study demonstrating control of hepcidin by estrogen in any animal.

Besides being an important iron-regulating hormone, researchers also suspect that hepcidin may act as an antimicrobial peptide in mammals, fish and frogs. Antimicrobial peptides are the first line of defense against disease-causing bacteria and some fungi and viruses in vertebrate animals.

"Our research suggests that estrogen-mimicking compounds may make fish more susceptible to disease by blocking production of hepcidin and other immune-related proteins that help protect fish against disease-causing bacteria," said Robertson.

USGS researchers Drs. Vicki Blazer and Luke Iwanowicz have previously found intersex occurring in fish in the Potomac and Shenandoah rivers. Intersex is primarily revealed in male fish that have immature female egg cells in their testes. Because other studies have shown that estrogen and estrogen-mimicking compounds can cause intersex, the co-occurrence of fish lesions, fish kills and intersex in these two rivers suggested to USGS scientists that estrogen-mimicking compounds could be involved in the fish lesions and fish kills in addition to being a possible cause of intersex traits.

That caused Robertson and her colleagues to investigate how estrogen could be affecting the immune system in these fish. The study showed that largemouth bass produced two different hepcidin proteins. Production of the first hepcidin protein was "turned down" by estrogen. Production of the second hepcidin protein by fish exposed to bacteria was blocked by estrogen. The fact that estrogen blocked production of hepcidins in fish exposed to bacteria gives more weight to the theory that estrogen or estrogen-mimicking chemicals could be making fish more susceptible to diseases, Robertson added.

Hepcidin could protect against bacterial infection in two ways. "First," said Robertson, "hepcidin could be an antimicrobial peptide that actually kills pathogens. Or it could be more complex. To live, a microbe must have iron, so when a microbe invades a person or animal, that microbe must obtain iron from its host. To 'fight' the microbe, a host can 'suck up iron' and store it in places inaccessible to the microbe. In mammals, hepcidin is a key player in how the host takes up and stores iron."

The study, Identification of centrarchid hepcidins and evidence that 17β-estradiol disrupts constitutive expression of hepcidin-1 and inducible expression of hepcidin-2 in largemouth bass (Micropterus salmoides), was just published in the journal, Fish & Shellfish Immunology. The authors are USGS scientists Laura Robertson, Luke Iwanowicz and Jamie Marie Marranca.


'/>"/>

Contact: Laura Robertson
lrobertson@usgs.gov
304-724-4579
United States Geological Survey
Source:Eurekalert

Related medicine news :

1. Estrogen May Help Mens Hearts
2. Penn State professor investigates estrogen, heart disease connection in women
3. Estrogen May Combat Marijuanas Effect on Cognition
4. New study suggests Rx estrogen delivery through the skin may show safety benefits as opposed to oral delivery
5. Naturally produced estrogen may protect women from Parkinsons disease
6. Estrogen found to increase growth of the most common childhood brain tumor
7. Estrogen pills can benefit women with metastatic breast cancer
8. FDA Approves Durameds Synthetic Conjugated Estrogens-A Vaginal Cream
9. Estrogen therapy could be dangerous for women with existing heart risk
10. Estrogen May Explain Why Women With Cystic Fibrosis Suffer More
11. Estrogen and progesterone receptor isoforms expression in the stomach of Mongolian gerbils
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/26/2016)... ... May 26, 2016 , ... Connor Sports, ... as a partner for the Tamika Catchings Legacy Tour that will commemorate ... leader in hardwood basketball surfaces in all forms and levels of the game, Connor ...
(Date:5/26/2016)... ... 2016 , ... Cardiac arrhythmia is a common complication following ... survival, reports a team of UPMC researchers in the largest study of its ... Thoracic and Cardiovascular Surgery, provide critical information that will hopefully lead to better ...
(Date:5/26/2016)... ... May 26, 2016 , ... Catalent Pharma Solutions, ... biologics, consumer health and global clinical supply services, today announced two key appointments ... company’s continued investment and strategic growth plans in the Asia Pacific region. , ...
(Date:5/26/2016)... ... ... an effort to provide hair restoration information to the widest possible audience, Dr. Parsa Mohebi ... use the app. Dr. Mohebi, the founder of Parsa Mohebi Hair Restoration, is making all ... Dr. Mohebi says, “The positive response to the Snapchat videos we started last month has ...
(Date:5/26/2016)... ... May 26, 2016 , ... ... treatment for eating disorders, is opening a brand new child and adolescent residential ... 8-17 and their families with even more specialized eating disorder treatment and access ...
Breaking Medicine News(10 mins):
(Date:5/26/2016)... 26, 2016 According to a new ... Market - U.S. Industry Analysis, Size, Share, Growth, Trends, and ... the U.S. was valued at US$ 5.89 Bn in 2014 ... from 2015 to 2023 to reach US$ 7.99 Bn in ... and emerging needle free drug delivery devices and the market ...
(Date:5/26/2016)... May 26, 2016   Change Healthcare ... analytics, network solutions and technology-enabled services designed ... entered into a strategic channel partnership with ... software solutions and revenue cycle management services ... and rehabilitation clinics to optimize revenue, operational ...
(Date:5/25/2016)... India , May 25, 2016 ... Animation Market by Type (3D, 2D, 4D), by Therapeutic ... Education), by End User (Medical Device Manufacturers, Hospitals/ Clinics) ... studies the global Medical Animation Market for the forecast ... to reach USD 301.3 Million by 2021 from USD ...
Breaking Medicine Technology: