Short communicationsPre-clinical evidence for the efficacy and safety of α-amylase inhibitory peptides from cumin (Cuminum cyminum) seed

- CSPs demonstrated dose-dependent inhibitions and cytotoxic effects on AR42J cells.
- The safe and effective doses of CSPs were found in the range of 1.33-4.22 mg/ml.
- Efficacies of CSPs inhibitors were enhanced by increasing starch loads.
- CSPs able to sustain more than 50% of their initial inhibitions upon 2 h treatment.
- CSPs displayed non-competitive inhibition patterns.

Inhibitor of α-amylase offers an effective strategy to modulate hyperglycemia. Three novel cumin-seed peptides (CSPs) were proposed as potent inhibitors according to previous study. This study was performed to further assess the clinical relevance of CSPs in simulated physiological conditions via an in vitro model using AR42J α-amylase secretory cells. The CSPs displayed dose-dependent manners for bioactivities and cytotoxic responses. The IC50 values for inhibition were 5.6, 1.58, and 2.39 mg/ml, for CSP3, CSP4 and CSP6, respectively. The following starch load test further confirmed the efficiencies of CSPs as potent α-amylase inhibitor, as they were found capable of retaining more than 50% of their initial inhibition upon 2 h treatment. In addition, CSPs displayed mixed-type inhibition patterns with respect to soluble substrate (∼7.3-29.2 mM), suggesting that these peptide inhibitors have multiple binding modes to α-amylase. Therefore, CSPs exhibit promising potentials for development as new agents for the treatment of diabetic.