WHEY-PROTEIN SUPPRESSES THE OSTEOCLAST-MEDIATED BONE-RESORPTION AND OSTEOCLAST CELL-FORMATION

Effects of whey protein on bone resorption and osteoclastic cell forma tion were evaluated. In the pre-existed and newly formed osteoclast, i n bone resorption methods using an unfractionated bone cell culturing system, whey protein suppressed the area of pits formed by osteoclasts . In the osteoclastic cell formation method using the hemopoietic blas t cell culturing system, whey protein also suppressed osteoclastic cel l formation. These activities were resistant to heat when the protein was treated at 75-90 degrees C for 10 min. Heat-treated whey protein w as first fractionated on a Mono S column, and the active fraction (bas ic protein fraction) was then applied to Superose 12. The molecular we ights of the active components were approximately 23000 and 10000 Da, as determined by gel filtration. The inner solution of an everted gut- sac incubated in a solution of intact basic protein (BP), pepsin-diges ted BP or pepsin/pancreatin-digested BP also suppressed osteoclast-med iated bone resorption. Thus, these active components can possibly be a bsorbed or transported by the intestines. These results showed that wh ey protein contains an active component that suppresses osteoclast-med iated bone resorption and osteoclastic cell formation. (C) 1998 Elsevi er Science Ltd. All rights reserved.