Researchers at the University of Oregon synthesized organic molecules that break down and release hydrogen sulfide under certain biological conditions such as oxidative stress, and may protect cells.
Oxidative stress is an imbalance between the production of free radicals and the ability of cells to detoxify them. These free radicals or reactive oxygen species are harmful to the cells and are associated with a number of diseases, including Parkinson’s disease (PD).
Hydrogen sulfide is a colorless and toxic gas found in the environment. But it is also produced in small amounts in mammalian cells and plays a vital role in regulating inflammation response. It is thought that it could have therapeutic properties for diseases associated with oxidative stress, such as Parkinson’s.
The newly designed molecules remains stable and nontoxic inside cells until oxidative stress triggers them to release carbonyl sulfide, which is then converted into hydrogen sulfide by an enzyme in the body called carbonic anhydrase.
“We have discovered that small organic molecules can be engineered to release a molecule called carbonyl sulfide, which is the most prevalent sulfur-containing molecule in the atmosphere, but more importantly converts rapidly to hydrogen sulfide under biological conditions,” Dr. Michael Pluth, a professor of chemistry at the University of Oregon, explained in a press release. “We developed and demonstrated a new mechanism to release small molecules that provide therapeutic hydrogen sulfide.”
However, the research is at the cellular level and laboratory-based and still far from medical applications.
“We are synthetic chemists. We make molecules with the goal of developing new research tools or therapeutic tools,” Pluth said in the press release. “As for treating a disease, we aren’t there yet, but these cell-based studies suggest that those types of protective effects might be possible.”
According to Pluth, the novelty of this research is that they were able to use carbonyl sulfide as a source of hydrogen sulfide. “It opened up a whole new class of donor molecules,” he said, and explained that currently available hydrogen sulfide donors are slow-release molecules that donate hydrogen sulfide passively while the newly developed molecules are programmed to quickly react to reactive oxygen species.
Different parts of the findings were published in two scientific journals. One was titled “Self-Immolative Thiocarbamates Provide Access to Triggered H2S Donors and Analyte Replacement Fluorescent Probes” and was published in the Journal of the American Chemical Society, and the other was titled “Hydrogen Sulfide Donors Activated by Reactive Oxygen Species” and was published in the international edition of the German journal Angewandte Chemie.