Professor Peter Shepherd and his team believe that caffeine and theophylline- compounds commonly found in cola beverages, coffee, tea and chocolate - block the operation of a key enzyme linked to a wide range of cell functions. This suggests these compounds would block cell growth and also blood clotting. The teams work may also explain the anti-inflammatory properties of theophylline, a drug used for many years in asthma treatment.
The enzyme, PI-3 Kinase, is thought by scientists to play a key role in the signalling mechanism which determines cell growth and death. The particular form of the enzyme targeted by caffeine - called p110 delta -was also recently found by another UCL team for being responsible for orchestrating the human body's response to infection and to be potentially involved in the development of irritable bowel disease.
Operating deep within the cell, PI-3 Kinase stimulates phosphates to be attached onto a particular lipid sited within the membrane of the cell. This process triggers the signalling pathways which ultimately control cell growth, movement and survival.
In the studies, genetically engineered insect cells were used to produce p110delta and a standard biochemical test was conducted to establish if phosphates had indeed attached to lipids. Interestingly caffeine and the closely related molecule theophylline blocked this process, providing compelling evidence that caffeine had indeed acted to block the functioning of the p110 delta enzyme.
Speaking today Professor Peter Shepherd, at UCL's Department of Biochemistry and Molecular Biology, said;
" We've shown that caffeine like compounds play a novel role in blocking enzymes known to play a critical role in a range of cellular functions in the body. Along side possible advances in cancer treatm
Contact: Patrick Edwards
University College London