title: Wnt-signaling-mediated antiosteoporotic activity of porcine placenta hydrolysates in ovariectomized rats.
abstract: Anti-osteoporotic effects of two types of porcine placenta hydrolysates (PPH) were evaluated in ovariectomized (OVX) rats orally administered PPH without (WPPH) or with (NPPH) ovarian hormones (1 g/kg bw/day). PPH groups were compared with OVX rats with estrogen replacement (0.1 mg/kg bw conjugated estrogen; EST), or dextrose (placebo; OVX-control) All rats received high-fat/calcium-deficient diets for 12 weeks. NPPH contained less estrogen and progesterone, but more essential amino acids, whereas the opposite was true for WPPH. NPPH decreased body weight and peri-uterine fat pads, and maintained uterus weight. NPPH rats had higher femur and lumbar spine bone mass density compared to controls; but less than those of EST rats. Serum phosphorus and urinary calcium and phosphorus levels were reduced in NPPH rats compared to OVX-controls. Serum bone-specific alkaline phosphatase, osteocalcin, and bone turnover marker levels were reduced NPPH rats compared to OVX-controls. WPPH produced results similar to those of NPPH, but less significant. Both NPPH and estrogen upregulated low-density lipoprotein receptor-related protein 5 and β-catenin in OVX rats, while the expression of dickkopf-related protein 1 was suppressed. In conclusion, NPPH exerted anti-osteoporotic effects by activating osteogenesis and stimulating Wnt signaling, possibly mediated by the various amino acids and not ovarian hormones.
authors.affiliation: Korea Institute of Oriental Medicine, Daejeon 305811, Republic of Korea.
authors.forename: Byoung-Seob
authors.initials: BS
authors.lastname: Ko
authors.forename: Da Sol
authors.initials: DS
authors.lastname: Kim
authors.forename: Suna
authors.initials: S
authors.lastname: Kang
authors.forename: Na Ra
authors.initials: NR
authors.lastname: Lee
authors.forename: Jin Ah
authors.initials: JA
authors.lastname: Ryuk
authors.forename: Sunmin
authors.initials: S
authors.lastname: Park