Osteo-modulatory dietary proteins and peptides: A concise review

The integrity of the bone is dependent on the strict balance between osteoclastogenesis and osteoblastogenesis, and any imbalance results in bone diseases. Dietary proteins (DP) have been shown to promote osteogenesis while inhibiting bone resorption in cultured osteoblasts, and in animal models of bone diseases such as ovariectomy, 1α,25-dihydroxy-vitamin D3 (VD3), and prostaglandin E2 (PGE2)-induced bone resorption. Hydrolysis of some of these DPs with osteo-modulatory properties has been shown to generate hydrolysates with bioactive peptides that exhibit higher osteo-modulatory properties in comparison to intact (parent) proteins. The higher bioactivity of the isolated peptides and protein hydrolysates compared to intact proteins indicates that the osteo-modulatory properties are dependent on the degree of exposure of the functional groups of amino acid residues involved in target interaction. This review provides an overview of the preparation of DP and select peptides with osteo-modulatory properties, and summarizes the potential underlying mechanisms of action through which the bioactive peptides help maintain bone health. PRACTICAL APPLICATIONS: Bone diseases such as osteoporosis (OP), osteoarthritis (OA), bone cancer (BC), and others have negative impacts on the quality of life, especially in older women after menopause. Current drugs used in treating many bone diseases such as bisphosphonates, anabolic steroids, and selective estrogen receptor modulators have been limited by worrisome adverse effects such as organ toxicity, increased risk of cancer, and cardiovascular abnormalities, and gastrointestinal discomfort. There is growing scientific evidence that certain multifunctional dietary proteins and bioactive peptides may positively modulate bone health by modifying risk factors for bone diseases including inflammation, oxidative stress, hyperlipidemia, and hyperglycemia.