Biological Function Of Peptide From Meretrix Meretrix Linnaeus

Antineoplastic agents have been identified and isolated nowadays, and they provide new resources of antineoplastic drugs. For the past several years, many antineoplastic materials with original structures have been identified from marine organisms. And this presents a marvelous prospect in drug discovery area. Screening and extracting antineoplastic agents with unique chemical constitution from marine lives and their metabolites becomes more and more important. Meretrix meretrix Linnaeus is a kind of popular ocean mollusks, which values are shown not only in the abundant nutrition, but also in the use as a resourse of medicine. It can eliminate cyst and detoxify the body so that it can inhibit the cancer of liver,lung,kidney and goiter and so on, also it can decrease the level of blood sugar and blood fat. And it can also protect body cells from mutation or decrepitude. The active components along with its physiological function have aroused popular attention.In this study, we obtained five peaks through a series of methods including fragmentation, organic precipitation and Sephadex G-25 column chromatogram. We tested the inhibitory effect of five peaks on cancer cells and found that the substance of peak2 could inhibit the growth of cancer cells, which was called mer2. We used mer2 to treat the Hela cells, the human lung adenocarcinoma A549 cells and the human cholangiocarcinoma QBC939 cells, and investigated the biological effects of mer2 on cells and functional characteristics, and further study the functional mechanism of the peptide on cells. The result of MTT showed that mer2 could inhibit growth of the cells. And the /C50 to lung adenocarcinoma A549 and cholangiocarcinoma QBC939 cells were all lower than 40μg/mL. We investigated the effects of the peptide on the shape and cell-cycle of lung adenocarcinoma A549 cells by microscope, Hoechst staining and flow cytometry. We found that shapes of cells treated by the peptide had been changed distinctly, showing an obvious apoptotsis properties. It indicated that the inhibitory effect of the peptide on cells had a relationship with the cell apoptotsis.By using the method of dynamics, we studied the effect of the peptide on Alkaline Phosphatase (ALPase),Creen Crab (Acylla Serrata) N-Acetyl-β-D-gluco-saminidase (NAGase),mushroom Tyrosinase. The peptide showed mix-competitive type inhibitory effect on NAGase, the value of IC₅₀ is 112.9μg/mL and a noncompetitive type inhibitory effect on the mushroom Tyrosinase, the value of /C50 is 85μg/mL.Meanwhile, the peptide showed an activity of anti-lipidperoxidation.