Therapeutic potential of fish collagen hydrolysates in osteoporosis prevention: a narrative review based on cellular, molecular, and clinical evidence.

Osteoporosis is a prevalent bone disorder diagnosed by diminished bone density and deterioration of skeletal microarchitecture. Adverse side effects caused by the prolonged use of anti-osteoporotic medications have prompted researchers to find safe and natural therapeutic compounds to manage osteoporosis. Among natural compounds, fish collagen hydrolysates (FCHs) derived from fish processing wastes offer a safe, inexpensive, and environment-friendly alternative to mammalian collagen. This review critically evaluates the preclinical and clinical evidence for the therapeutic effectiveness of FCHs on bone cell biology, highlighting their potential in osteoporosis prevention. The review also highlights high bioavailability, biocompatibility, and the potential of fish collagen peptides to influence bone metabolism. Evidence of increased bone mineral density and improved bone microarchitecture has also been discussed in vivo, along with key regulatory markers of osteoblasts and osteoclasts function, including alkaline phosphatase (ALP), osteocalcin (OCN), osteopontin (OPN), runt-related transcription factor-2 (Runx-2), bone morphogenetic protein (BMP-2), receptor activator of nuclear factor κ B ligand (RANKL), tartrate-resistant acid phosphatase (TRAP), and cathepsin K. Although early clinical trials suggest beneficial effects on bone turnover and bone mineral density, robust, large-scale randomized studies are still needed to confirm these findings. FCHs thus present a promising but still developing therapeutic avenue in the prevention and management of osteoporosis.