Enzyme protein eight times more effective against pain than morphine

The enzyme protein found naturally in the body alleviated pain eight times more effectively than morphine. Research findings are published this week as the cover story of the esteemed Neuron journal.

Professor Pirkko Vihko from the Department of Biological and Environmental Sciences of the University of Helsinki has conducted research on the Prostatic Acid Phosphatase (PAP) enzyme for more than 30 years. As the name indicates, the prostate contains plenty of this enzyme.

Last year, Vihko's research team described the membrane form of the enzyme and showed that it is present not only in the prostate, but in many other cells and organs as well. The PAP enzyme exists, for example, in pain-sensing nerves, but it has disappeared from damaged nerves.

For the research project presented in the Neuron journal, Vihko and her team prepared a knockout mouse model with the PAP enzyme knocked out. Together with Mark Zylka's team from the University of North Carolina they showed that these mice had an increased sensitivity for pain caused by inflammation and neural damage. The reason for the sensitivity was the lack of the PAP enzyme. Enzyme protein replacement treatment removed pain effectively – eight times more so than morphine. Clinical research will begin next.

Research teams also determined the mechanism that the acid phosphatase of the prostate uses to regulate pain alleviation. In an organism, the enzyme generates adenosine that controls the experience of pain through the adenosine receptor. Vihko’s team will prepare new publications that describe the entirely new effective areas of the enzyme.