A Study on Action of Lycopene in Neuroprotection Phenomenon in Rat Pheochromocytoma PC 12 Cell Lines

Abstract

Lycopene, a carotenoid, is found in particularly high amounts in tomatoes. Like all carotenoids, lycopene is a polyunsaturated hydrocarbon (an un-substituted alkene). Structurally, it is a tetra-terpene assembled from eight isoprene units. Lycopene s eleven conjugated double bonds give it its deep red color and are responsible for its antioxidant activity which is 47 and 100 times greater than that of and#946;-carotene and vitamin E respectively. Reactive oxygen species mediated tissue injury is the final common pathway for a myriad of disease processes. The body is continuously exposed to free radicals and ROS, both from external sources and endogenously generated sources. Oxidative stress and oxidative damage to tissues are common end points of chronic neurological diseases such as Parkinson s disease, schizophrenia, depression, etc. During oxidative stress there is a reduction in antioxidant levels which can further increase the deleterious effects of free radicals. The common free radicals are reactive oxygen species (ROS) namely, superoxide radical, hydroxyl radical and peroxide radical which can be internally produced by cellular metabolism, inflammation by immune cells and externally by radiation, hydrogen peroxide, toxic chemicals, smoke, alcohol. Free radicals can cause neurodegeneration, heart damage, cancer, cataracts and a weak immune system. Antioxidants work by neutralizing highly reactive destructive compounds called free radicals. They transform free radicals into non-damaging compounds or repair cell damage. They are able to donate electrons easily to molecules in need of an electron, before they steal from some other place, thus stabilize and prevent a damaging chain reaction. Antioxidants help to neutralize the production of free radicals and serve as a source of electrons that can be provided to free radicals. They prevent unstable oxygen molecules from interacting with other molecules and consequently causing them to become unstable, a process that starts the free radical chain reaction.