Abstract:

Objective: To investigate the effects of collagen peptides from tilapia skin on the proliferation ability of humancolon carcinoma cell line LoVo in vitro and its possible mechanism. Methods: The inhibitory effects of collagen peptidesfrom tilapia on the proliferation of LoVo cells were observed by MTT assay. Fluorescent staining method was used toanalyze the effect on cell membrane and nucleus. Laser confocal microscopy was used to examine reactive oxygen species(ROS) expression in LoVo cells. The activities of mitochondrial respiration chain complex I and III were analyzed bycolorimetry. Results: Collagen peptides from tilapia skin showed certain inhibitory effect on the proliferation of LoVocells. After being treated by 100 mg/mL of collagen peptides for 48 h, the growth inhibitory effect rate reached 55.03%(P < 0.05). Compared with the control group, the nucleus of LoVo cells was shrunk and cell membrane was destructed afterbeing treated by collagen peptides. Meanwhile, the ROS level was significantly increased (P < 0.05). Collagen peptidessignificantly inhibited the activity of complex III. Conclusion: Collagen peptides from tilapia skin have inhibitory effects onthe proliferation of human colon carcinoma cells, which is probably associated with the inhibited activity of mitochondrialrespiration chain complex III in LoVo cells, promoting ROS expression and destructing the cell membrane in LoVo cells.

Key words: tilapia skin, collagen peptides, colon carcinoma, reactive oxygen species (ROS), mitochondrial respiratory chain complex