Orbitides isolated from flaxseed induce apoptosis against SGC-7901 adenocarcinoma cells

Abstract

Unique plant-derived cyclic peptides family exhibiting various key biological activities has great possibility for anticancer therapy. In this study, we investigated the effects of orbitides isolated from flax (Linum usitatissimum L.) on the growth of SGC-7901 cancer cells and the potential mechanism. Results showed that flaxseed orbitides killed off cancer cells by inducing apoptosis in a dose-dependent manner, which was confirmed by the appearance of nuclear shrinkage and DNA fragmentation, and the inhibitory effect was stronger than that of pure orbitide [1–9-NαC]-linusorb B2 or [1–9-NαC]-linusorb B3. Besides, the mitochondrial apoptosis pathway-related protein cytochrome C (Cyt C) was released from mitochondria to cytosol, associated with the activation of caspases 9 and 3, and the cleavage of PARP. Taken together, these results indicated that flaxseed orbitides induced apoptosis via the mitochondrial pathway, releasing Cyt C, increasing Bax/Bcl-2 ratio and elevating the expression of cleaved caspase 9 and 3 in SGC-7901 cells.

Graphical Abstract

Keywords:

• Flaxseed
• orbitides
• cell viability
• apoptosis
• mitochondria

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors thank National Natural Science Foundation of China [31560464] and Goal Oriented Project of Sate Key Laboratory of Food Science and Technology, Nanchang University [SKLF-ZZA-201610] for financially supporting this project.