Halting Drop of Blood Pressure During Septic Shock

A study has found that administering a superoxide dismutase (SOD) mimetic to a rat model of septic shock can remove excess superoxide free radicals, restoring the ability of norepinephrine to constrict blood vessels and reverse hypotension. The study, conducted by researchers from the Saint Louis University School of Medicine (MO, USA) and MetaPhore Pharmaceuticals (St. Louis, MO, USA; www.metaphore.com), was reported in the August 15 issue of Proceedings of the National Academy of Sciences.

The researchers confirmed that free radicals--particularly superoxide anions--produced in large quantities during septic shock deactivate dopamine, norepinephrine, and epinephrine, destroying their biologic activity and often leading to a life-threatening free fall in blood pressure. The standard treatment is antibiotic therapy and intravenous fluids and catecholamines such as dopamine and norepinephrine to prevent a fall in blood pressure. However, the additional catecholamines administered are often destroyed by the huge excess of superoxide free radicals, produced as the body fights infection.

The SOD mimetic (M40403) is a specially constructed manganese-based compound developed by MetaPhore. Unlike the natural enzyme it simulates, MetaPhore's SOD is well-suited for use as a drug because it has a low molecular weight, as well as considerable oxidative and kinetic stability. According to MetaPhore, the SOD mimetics family has also shown promise in treating inflammation, pain, cancer, rheumatoid arthritis, and reperfusion injury and stroke.