Effects of enzymatic hydrolysate from seahorse Hippocampus abdominalis on testosterone secretion from TM3 Leydig cells and in male mice

Protein hydrolysates, the so-called bioactive peptides, are specific protein fragments that have positive effects on several body functions and may improve human health. Marine organism-derived protein hydrolysates and bioactive peptides have shown to possess many physiological functions. Seahorses, used in traditional medicine, are generally ground to powder form either for direct application or for application following dissolution in warm water. In this present study, we purified, hydrolyzed, and characterized two bioactive peptides (ALC and PEP) obtained from seahorse (Hippocampus abdominalis). The hydrolysates derived from seahorse significantly upregulated the expression of cyclin D and cyclin E and increased cell proliferation and testosterone level in the TM3 mouse Leydig cell line. These findings suggest that the hydrolysates stimulate the proliferation of TM3 cells via the AKT, ERK, and JNK pathways. The decline in the circulating testosterone levels in older men is associated with various adverse health effects. Following daily intake of hydrolysates for 12 weeks, the circulating level of testosterone and the sperm count in mice were measured. We found increased sperm motility (sperm count) as well as an increase in the testosterone level in male mice following a 12-week intake of hydrolysates derived from H. abdominalis. Hence, it can be suggested that seahorse-derived hydrolysates play an important role in improving male health by improving the serum testosterone level.