June 18, 2013
New Probe Lets Researchers Watch As Body Makes ‘Rotten Egg’ Gas
Watch the video "Chemical Lights Up Rotten Egg Gas In Body's Cells"
Brett Smith for redOrbit.com - Your Universe Online
Researchers from Southern Methodist University in Dallas have devised a chemical probe that allows for the visualization of an important process in the human body, the generation of hydrogen sulfide.
Best known for its role in producing the “rotten egg” smell associated with certain bodily processes, hydrogen sulfide is also very important for the promotion of cardiovascular health, among other things.
“We made a molecular probe that, when it reacts with hydrogen sulfide, forms a fluorescent compound that can be visualized using fluorescence microscopy,” said Alexander R. Lippert, a chemistry professor at SMU and co-author of a report on the project that was recently published in the Proceedings of the National Academy of Sciences.
“This is the first time that endogenously generated hydrogen sulfide has been directly visualized in a living system,” Lippert added. “This confirms a lot of hypotheses that scientists have, but no one had the tools to directly detect it in real time.”
Before the SMU study, scientists had not been able to observe hydrogen sulfide generation in live cells. The new discovery allows researchers to see precisely how and when hydrogen sulfide is created, Lippert said.
“Having the tools to do this in living systems is going to open up a lot of possibilities and experiments for scientists,” the chemist explained. “As a tool, this will allow researchers to ask questions that weren´t possible before.”
Lippert and his co-authors from the University of California at Berkeley were able to capture real-time video of their chemical probe at work. The videos show live human cells taken from blood vessels and treated with both the chemical probe and a protein known to promote cell growth. Once the cells began making hydrogen sulfide, they squirmed about the screen like fluorescent green worms.
“Essentially we´re observing the initial events that lead to the building of new blood vessels, a process that´s active in babies as they develop, or in women during their menstruation cycles,” Lippert explained.
“We see the cells get really bright as they start moving around and ruffling their membranes,” he said. “That´s the (hydrogen sulfide) being formed. In the control group, which weren´t stimulated with the growth protein, they don´t get any brighter and they don´t move around.”
The researchers said their work could have ramifications for cancer treatments that involve starving a tumor of its nutrient supply.
“When tumors grow they need a lot of blood support because they need the nutrients to support their rapid growth,” he said. “If you can stop blood vessel formation you could starve the tumor and the tumor will die. So inhibiting (hydrogen sulfide) formation might be a way to treat cancer using this method.”
Hydrogen sulfide is one of several small gaseous molecules gaining a reputation as a major signaling molecule in the human body. Previous research has shown that human cells generate small amounts of hydrogen sulfide to deliver information to proteins. Proteins then act on this information to perform critical jobs throughout the body, such as digesting food or generating energy from oxygen.