Bioassay-guided isolation and evaluation of anti-osteoporosis active polysaccharides from Morinda officinalis

Ethnopharmacological relevance: As a famous Chinese tonic herb for the bones and joints, the clinical efficacy of Morinda officinalis has shown its advantages in the treatment of bone disease. However, the anti-osteoporosis potential and responsible ingredients of M. officinalis polysaccharides (MOPs) worth further investigation.

Aim of the study: This study aimed to investigate the antiosteoporosis effects of different MOP fractions in ovariectomized (OVX) rats, and identify the responsible osteoprotective ingredients by bioassay-guided isolation.

Materials and methods: MOPs were prepared by hot water and alkali extraction, separated into three fractions (MO50, MO70, and MOB) and evaluated in the classic OVX rat model and MC3T3-E1 cells for anti-osteoporosis activity.

Results: Administration of MOPs (400 mg/kg/day) could significantly prevented ovariectomy-induced bone loss, biomechanical reduction, deterioration of trabecular microarchitecture and high levels of bone turnover markers in rats. Bioactivity-guided fractionations led to the isolation of two inulin-type fructans MOW50-1 and MOP50-2 with potential anti-osteoprotic activities from MO50, consisting of (2→1)-linked β-D-fructosyl residues (DP = 7 and 13, respectively). Besides, MOW50-1 promoted the osteogenic differentiation of MC3T3-E1 cells by increasing alkaline phosphatase activity.

Conclusions: These data suggest very strongly that MOPs, especially MO50 and MOW50-1, may play an important role in osteoporosis prevention and treatment.

Keywords: ); MOP50-2; MOW50-1; MOW50-1, MOP50-2 were inulin-type fructans with a backbone consisted of α-D-Glcp-(1→, →1)-β-D-Fruf-(2→ and β-D-Fruf-(2→ residues (DP = 7 and 13, respectively; Morinda officinalis How; osteoporosis; ovariectomized rats; polysaccharide; structural characterization.