Inhibitory Effects of the Leaves of Loquat (Eriobotrya japonica) on Bone Mineral Density Loss in Ovariectomized Mice and Osteoclast Differentiation

Abstract

The loquat, Eriobotrya japonica Lindl. (Rosaceae), is a small tree native to Japan and China that is widely cultivated for its succulent fruit. Its leaves are used as an ingredient of a tasty tea called "Biwa cha" in Japanese. The anti-osteoporosis effects of the leaves of loquat in vitro and in vivo have been investigated. After 15 days of feeding normal diet or diet supplemented with 5% loquat leaves, the body weight, viscera weights, and bone mineral density (BMD) of both groups of eight ovariectomized (OVX) mice were compared. The result showed that the loss of BMD in loquat-fed mice was significantly prevented in three parts of the body, especially in the trabecular bone of the head (P < 0.05), abdomen (P < 0.01), and lumbar (P < 0.05) compared to the control group. No hypertrophy in the uterus by the loquat leaves diet was observed. The effect of the extract (447.25 g) prepared from the dried leaves of loquat (2.36 kg) was further studied on RANKL-induced osteoclast differentiation and cell viability. The extract suppressed the differentiation of osteoclasts under 50, 125, 250, and 500 μg/mL. Through bioactivity-guided fractionation, ursolic acid (1) was isolated and inhibited osteoclast differentiation under 4 and 10 μg/mL. It was concluded that loquat leaves possess the potential to suppress ovariectomy-induced bone mineral density deterioration.

Inhibitory effects of ursolic acid on osteoclastogenesis and titanium particle-induced osteolysis are mediated primarily via suppression of NF-κB signaling

“…Furthermore, they showed that the expression of osteoblast-specific genes was enhanced after UA treatment, and that UA could induce osteoblastogenesis and mineralization of osteoblasts in vitro, which was associated with the activation of MAPKs, activator protein-1 (AP-1), and NF-kB [12]. Further, Tan et al observed that UA extracted from loquat leaves inhibited bone mineral density loss in ovariectomized mice [13]. These findings suggest that UA may be valuable for the treatment of metabolic osteopathy characterized by bone mass loss.…”

The Potential of Triterpenoids from Loquat Leaves (Eriobotrya japonica) for Prevention and Treatment of Skin Disorder

“…In addition, loquat leaves may ameliorate Alzheimer’s disease, since E. japonica leaves protect against oxidative stress and cognitive deficits induced by the Aβ peptide [13]. Our previous studies showed that E. japonica have the potential to suppress ovariectomy-induced bone mineral density deterioration [14], and isolated triterpenoids as the major bioactive compounds suppress osteoclast differentiation [15]. As a powerful indigenous therapy, loquat leaves have also been used for skin-care application such as for sunburn, dermatitis, and skin aging.…”

Phosphorylated peptides from Antarctic Krill (Euphausia superba ) improve fracture healing in mice with ovariectomy induced osteoporosis

“…Ovariectomized mice have been classically used as animal models for simulating osteoporosis of postmenopausal women (Lee et al, ; Tan et al, ). Since there are no apparent symptoms in early‐stage of osteoporosis, BMD test has been regarded as an effective means to diagnose this disease (Seeman, ).…”