Who Knew I Could Relate to a Frog?
Courtney Golden (11 AM Micro) is worried about frogs, and found an article on Science Daily showing a link between an herbicide, a fungus, and how immunity of amphibians is affected by environmental levels of the herbicide. Courtney seems a bit surprised to find out about that amphibians have an immune system just as powerful as a human, however long time readers of BIO230 will recall my ode to the Nobel Prize winning work Jules Hoffman, who studied the ability of fruit flies to fight off fungal infections, and how the mechanisms are absolutely conserved by the human immune system. Courtney’s title could also be rewritten as “Who knew I could relate to a Fruit Fly?” Here is what Courtney has to say about frogs:
Whenever I think of frogs, I think of little green creatures that hop around and “ribbit-ribbit” in the local ponds and streams. Frogs are much more than a green, hoppy, amphibian. Frogs are an important part of our ecosystem. According to Science Daily, frogs have immune systems just like ours, and while treating the land and our crops with herbicides; the herbicide atrazine has shown an increase in mortality rates in frogs. The herbicide atrazine can be deadly to frogs when exposed at an early age, but why is this herbicide so deadly? Atrazine works together with Chytridiomycota fungus. The Chytridiomycota fungus is a typical pathogen to frogs, but usually the infection is fought off by their immune system. The USF’s Department of Integrative Biology showed that when frogs were exposed early in development to atrazine, one of the most common herbicides used today, and were exposed to Chytridiomycota fungus, the fate of the frog was fatal. The herbicide atrazine can cause frogs to die within 46 days of exposure to the herbicide. A direct relationship is shown through the exposure of atrazine and the frog’s death. The death occurs because as the frog become exposed to atrazine, their immune systems cannot fight off the usually typical Chytridiomycota fungal infection, and their immunity deteriorates with time.
This certain case of atrazine herbicide and Chytridiomycota fungual infections show an instance of chance that one specific frog, could be exposed to a specific herbicide, and then exposed to a certain fungal infection, creating loss of immunity in the frog, just like how it could happen to a human. This mirrors the case in the Frontline episode we watched on Friday, October 25th, 2013. The little girl Addie, who was infected with a superbug, received some of the bug by coincidence. Addie picked at her scabs and contracted a Staph infection, which in turn opened the door for other infections. Just by this chain of coincidental events Addie and the frog both contracted diseases in which their bodies could not fight off, and her life depended on a lung transplant. Although one infection was fungal and the other was a Gram-negative bacteria, in both instances immunity was lost and death was a possibility.
In an additional article published by NPR, in a scientific study done by Jason Rohr, a biology professor at the University of South Florida in Tampa also showed that with increased amounts of atrazine, snail population flourished which is a kiss of death for frogs. The snails carry flatworm parasites, and due to the fact that atrazine damages and deteriorates the frog’s immune systems, the frogs cannot fight off the parasites.
It is crazy to think that frogs and humans have biological connections, including their immune systems. I have always just thought of a frog as a little green slimy creature that hops around on four legs and “ribbits” and croaks loudly to hear; but that is not the case, frogs have immune systems and diseases as well, just like humans.