Whereas at low concentrations, hydrogen sulfide gas has been found to protect the heart from damage, the substance is unstable and volatile, rendering it difficult to deliver as therapy. David Lefer, from Emory University School of Medicine (Georgia, USA), have discovered that diallyl trisulfide, a garlic oil component, is a more stable and effective way to deliver the benefits of hydrogen sulfide to the heart. Their findings suggest that doctors could use diallyl trisulfide in many of the situations where researchers have proposed using hydrogen sulfide.  The researchers blocked coronary arteries of mice for 45 minutes, simulating a heart attack, and gave them diallyl sulfide just before blood flow was restored. The compound reduced the proportion of damaged heart tissue in the area at risk by 61%c, as  compared with untreated animals.  "Interruption of oxygen and blood flow damages mitochondria, and loss of mitochondrial integrity can lead to cell death," comments Lefer, who submits that: "We see that diallyl sulfide can temporarily turn down the function of mitochondria, preserving them and lowering the production of reactive oxygen species."