Hematological assessments of sericin-derived oligopeptides in BALB/c mice

摘要

Sericin, a protein removed from the silk cocoons, possesses various biological activities. Due to less solubility, utilization of the sericin protein may be limited. Enzymatic hydrolysates of this protein would thus, provide an alternative. Since safety assessment is required before any protein hydrolysates being used, the effects of sericin-derived oligopeptides (SP) on some hematological parameters were evaluated. Female BALB/c mice were fed orally with SP (50, 100 and 500 mg/kg body weight daily) or vehicle for 28 days. The total red blood cells (RBCs), percent (%) hematocrit, differential white blood cells (WBCs) and lymphocyte subpopulations were determined. SP, either 50, 100 and 500 mg/kg did not significantly influenced counts of the RBCs and % hematocrit. In addition, SP did not affect the number of types of WBCs. No changes in morphology of RBCs and WBCs were observed. These suggested that SP were not harmful to both RBCs and WBCs. Preliminary immune modulation study demonstrated a significant increased population of the CD8+ (T cytotoxic) cells in mice fed with SP 50 and 500 mg/kg compared to the controls, suggesting immunomodulatory activity of such oligopeptides on the cell-mediated immunity. Our results indicate intoxic significance and warrant further investigations of such SP.