The Protective Effect Of Lycopene And Maca Extract On H₂O₂-induced Oxidative Damage Of PC12 Cells

Natural sources of lycopene is the most powerful antioxidant, it has excellent physiological functions. As a kind of functional colorant, lycopenc has many physiological functions, such as enhancing immunity ability, anti-cancer, anti-inflammatory, cardiovascular protection and so on.It is well known as "gold hidden in tomatoes". Maca?Lepidium meyenii Walp.?, has so many functions,like anti-fatigue, anti-oxidation, improving fertility, inhibiting BPH and improving sexual function,is a kind of crucifers growth Peru where is 3700-4500 meters above sea level.Therefore, it attracted much more attention around the world. The antioxidant is considered to be the basis of all the functions. So Maca and lycopene are particularly important in the study of anti-oxidation aspect. In this study, Maca and lycopene extract's antioxidant mechanism of cells was conducted a preliminary inquiry. Experimental divided into the following sections:1.PC12 cells were treated with 100 ?M?150 ?M?200 ?M?300 ?M?400 ?M concentration of hydrogen peroxide. After 4 h, cell viability was measured by MTT method. In the end,we used 150 ?M H₂O₂ to build cells oxidative injury model.2.PC12 cells were pretreated with concentration gradient of Maca, lycopene extract and after24 h and then 150 ?M H₂O₂ was added for 4 h to carry on oxidative damage. We used MTT method to measure cell viability. The final concentration of Maca was 100, 200, 500 ?g/mL and the final concentration of lycopene extract was 500, 600, 800 ?g/mL.3.The activity of lactate dehydrogenase?LDH? in extracellular fluid, the levels of cellular reactive oxygen species?ROS?, cellular lipid peroxidation?MDA?, glutathione?GSH?, and antioxidant enzyme activities were measured as biomarkers of cellular oxidative status. Maca and lycopene extract's antioxidant activity and antioxidant effect are better than VE and lycopene standards. We determined the optimal concentration of Maca?500 ?g/mL? and lycopene extract?800 ?g/mL?.The following studies were used the optimal concentration.4.By measuring the changes in mitochondrial membrane potential, early situation of apoptotic cells was observed. And the cell cycle was determined by flow cytometry, a preliminary inquiry of antioxidant mechanisms on Maca and lycopene extract was studied. The results showed thatafter adding 150 ?M H₂O₂ for 4 h, the mitochondrial membrane potential appear early apoptosis.No significant late apoptotic cells were showed by flow tests.but the cell cyclin showed S phase fraction increased. After pretreatment of lycopene extract and Maca, the mitochondrial membrane potential has been recovery in some extent, cell cycle progression in S phase was reduced and the number of cells in G2/M phase was increased, indicating that the DNA damage was reduced, cells can be proliferation smoothly.