New Discovery: How Zinc Can Help with Infections
By Jeff Jurmain - February 13, 2013
Disclaimer: Results are not guaranteed*** and may vary from person to person***.
Zinc keeps your immune system in check.Zinc is known to help fight off viruses and bacteria, and a new study shows one big reason why: zinc controls infections by gently halting the body¡¯s immune response in order to prevent inflammation that can be quite damaging.
What happens is that a protein lures zinc into cells that are first-responders against infection. Zinc moderates this fight and, as such, helps balance your immune response. For the first time, we find out that zinc hones in here to ensure the immune system does not spiral out of control. If a virus strikes and you have low levels of zinc, the consequences include excessive inflammation (the cause of a myriad of illnesses).
These findings may help to explain why taking zinc tablets or lozenges at the start of a common cold helps to stem the effects of the illness. But the big thing to note here is that without proper zinc levels during an infection, you are at a disadvantage, because your defense system is inappropriately amplified.
About two billion people in the world suffer zinc deficiency. That includes 40% of older adults in the United States, the most likely demographic to end up in intensive care.
Previously, researchers showed that zinc-deficient mice experienced significant inflammation in response to ¡°sepsis¡± (the body¡¯s severe response to bacteria). Zinc supplementation improved outcomes in the zinc-deficient mice.
Until now, zinc¡¯s benefits in fighting infection haven¡¯t been fully understood. This is due to zinc¡¯s vastly complex role in our bodies. Only 10% of it, in fact, is accessible to defend against infection. So this helps narrow a gap in understanding¡ªwhich is always important when you are deciding which supplements to purchase.
The key word is ¡°balance¡±: our powerful immune system must work under strict balance. More is not always better. Zinc makes sure this balance is not left unchecked, which could result in too much inflammation and possible attacks against the body¡¯s healthy tissues (which leads to autoimmune diseases).
Zinc vs. Infections: New Insight
How zinc starves lethal bacteria to stop infection
Date: November 11, 2013
Source: University of Adelaide
Researchers have found that zinc can ¡®starve¡¯ one of the world¡¯s most deadly bacteria by preventing its uptake of an essential metal.
Australian researchers have found that zinc can 'starve' one of the world's most deadly bacteria by preventing its uptake of an essential metal.
The finding, by infectious disease researchers at the University of Adelaide and The University of Queensland, opens the way for further work to design antibacterial agents in the fight against Streptococcus pneumoniae.
Streptococcus pneumoniae is responsible for more than one million deaths a year, killing children, the elderly and other vulnerable people by causing pneumonia, meningitis, and other serious infectious diseases.
Published today in the journal Nature Chemical Biology, the researchers describe how zinc "jams shut" a protein transporter in the bacteria so that it cannot take up manganese, an essential metal that Streptococcus pneumoniae needs to be able to invade and cause disease in humans.
"It's long been known that zinc plays an important role in the body's ability to protect against bacterial infection, but this is the first time anyone has been able to show how zinc actually blocks an essential pathway causing the bacteria to starve," says project leader Dr Christopher McDevitt, Research Fellow in the University of Adelaide's Research Centre for Infectious Diseases.
"This work spans fields from chemistry and biochemistry to microbiology and immunology to see, at an atomic level of detail, how this transport protein is responsible for keeping the bacteria alive by scavenging one essential metal (manganese), but at the same time also makes the bacteria vulnerable to being killed by another metal (zinc)," says Professor Bostjan Kobe, Professor of Structural Biology at The University of Queensland.
The study reveals that the bacterial transporter (PsaBCA) uses a 'spring-hammer' mechanism to bind the metals. The difference in size between the two metals, manganese and zinc, causes the transporter to bind them in different ways. The smaller size of zinc means that when it binds to the transporter, the mechanism closes too tightly around the zinc, causing an essential spring in the protein to unwind too far, jamming it shut and blocking the transporter from being able to take up manganese.
"Without manganese, these bacteria can easily be cleared by the immune system," says Dr McDevitt. "For the first time, we understand how these types of transporters function. With this new information we can start to design the next generation of antibacterial agents to target and block these essential transporters."
Materials provided by University of Adelaide. Note: Content may be edited for style and length.
Rafael M Couñago, Miranda P Ween, Stephanie L Begg, Megha Bajaj, Johannes Zuegg, Megan L O'Mara, Matthew A Cooper, Alastair G McEwan, James C Paton, Bostjan Kobe, Christopher A McDevitt. Imperfect coordination chemistry facilitates metal ion release in the Psa permease. Nature Chemical Biology, 2013; DOI: 10.1038/nchembio.1382
How zinc starves lethal bacteria to stop infection -- ScienceDaily