Scientists say that people with atherosclerotic disease may someday be able to grow new blood vessels in their bodies which could help save ischemic limbs from amputation. Atherosclerosis is a condition in which an artery wall thickens as a result of the accumulation of fatty materials such as cholesterol. Commonly referred to as a hardening or furring of the arteries,it is caused by the formation of multiple plaques within the arteries. Now,a team from Stanford and Europe suggests that the delivery of genes for two molecules naturally produced by the body,called "PDGF-BB" and "VEGF",may successfully cause the body to grow new blood vessels that can save ischemic limbs. "We hope that our findings will ultimately develop into a safe and effective therapy for the many patients,suffering from blocked arteries in the limbs,who are currently not adequately treated by surgery or drugs. "This could help avoid the devastating consequences of limb amputations for both patients and their families," said Helen M Blau,a member of the team. To make this discovery,the scientists introduced the genes for PDGF-BB and VEGF into the muscles of mice,either independently or together. When high doses of VEGF alone were produced,they caused the growth of vascular tumours. When the two factors were produced in unbalanced amounts,tumour growth also occurred. And,when VEGF and PDGF were delivered in a fixed ratio relative to one another,however,no tumours occurred,and blood flow was restored to ischemic muscle tissue and damage repaired without any toxic effects.
