Abalone Haliotis discus hannai Intestine Digests with Different Molecule Weights Inhibit MMP-2 and MMP-9 Expression in Human Fibrosarcoma Cells

The abalone Haliotis discus hannai, is one of the economically important species in the fisheries industry. Abalone intestines are one of the by-products of its processing. To investigate its bioactive potential, abalone intestine was digested using an in vitro gastrointestinal (GI) digestion system containing pepsin, trypsin, and ${\alpha}$-chymotrypsin. The abalone intestine G1 digests (AIGIDs) produced by the GI digestion system were fractionated into AIGID I (> 100 kDa), AIGID II (10-100 kDa), and AIGID III (1-10 kDa) using an ultrafiltration membrane system. Of the three digests, AIGID II and AIGID III exhibited inhibitory effects against matrix metalloproteinase-2 and -9 (MMP-2, MMP-9) in HT1080 human fibrosarcoma cells. Both fractions potently inhibited gelatine digestion by MMP-2 and MMP-9 treated with phorbol 12-myristate 13-acetate (PMA) and migration of HT1080 cells in dose dependently. Furthermore, AIGID II and III attenuated expression of p65, a component of nuclear transcription factor kappa B. These results indicate that of the abalone intestine digests inhibit MMP-2 and MMP-9. Thus, the AIGIDs or their active components may have preventive and therapeutic potential for diseases associated with MMP-2 and MMP-9 activation in fibrosarcoma cells.