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Bone & Joint Research
Vol. 11, Issue 8 | Pages 528 - 540
1 Aug 2022
Dong W Postlethwaite BC Wheller PA Brand D Jiao Y Li W Myers LK Gu W

Aims. This study investigated the effects of β-caryophyllene (BCP) on protecting bone from vitamin D deficiency in mice fed on a diet either lacking (D-) or containing (D+) vitamin D. Methods. A total of 40 female mice were assigned to four treatment groups (n = 10/group): D+ diet with propylene glycol control, D+ diet with BCP, D-deficient diet with control, and D-deficient diet with BCP. The D+ diet is a commercial basal diet, while the D-deficient diet contains 0.47% calcium, 0.3% phosphorus, and no vitamin D. All the mice were housed in conditions without ultraviolet light. Bone properties were evaluated by X-ray micro-CT. Serum levels of klotho were measured by enzyme-linked immunosorbent assay. Results. Under these conditions, the D-deficient diet enhanced the length of femur and tibia bones (p < 0.050), and increased bone volume (BV; p < 0.010) and trabecular bone volume fraction (BV/TV; p < 0.010) compared to D+ diet. With a diet containing BCP, the mice exhibited higher BV and bone mineral density (BMD; p < 0.050) than control group. The trabecular and cortical bone were also affected by vitamin D and BCP. In addition, inclusion of dietary BCP improved the serum concentrations of klotho (p < 0.050). In mice, klotho regulates the expression level of cannabinoid type 2 receptor (Cnr2) and fibroblast growth factor 23 (Fgf23) through CD300a. In humans, data suggest that klotho is connected to BMD. The expression of klotho is also associated with bone markers. Conclusion. These data indicate that BCP enhances the serum level of klotho, leading to improved bone properties and mineralization in an experimental mouse model. Cite this article: Bone Joint Res 2022;11(8):528–540


Bone & Joint Research
Vol. 9, Issue 10 | Pages 667 - 674
1 Oct 2020
Antich-Rosselló M Forteza-Genestra MA Calvo J Gayà A Monjo M Ramis JM

Aims. Platelet concentrates, like platelet-rich plasma (PRP) and platelet lysate (PL), are widely used in regenerative medicine, especially in bone regeneration. However, the lack of standard procedures and controls leads to high variability in the obtained results, limiting their regular clinical use. Here, we propose the use of platelet-derived extracellular vesicles (EVs) as an off-the-shelf alternative for PRP and PL for bone regeneration. In this article, we evaluate the effect of PL-derived EVs on the biocompatibility and differentiation of mesenchymal stromal cells (MSCs). Methods. EVs were obtained first by ultracentrifugation (UC) and then by size exclusion chromatography (SEC) from non-activated PL. EVs were characterized by transmission electron microscopy, nanoparticle tracking analysis, and the expression of CD9 and CD63 markers by western blot. The effect of the obtained EVs on osteoinduction was evaluated in vitro on human umbilical cord MSCs by messenger RNA (mRNA) expression analysis of bone markers, alkaline phosphatase activity (ALP), and calcium (Ca. 2+. ) content. Results. Osteogenic differentiation of MSCs was confirmed when treated with UC-isolated EVs. In order to disprove that the effect was due to co-isolated proteins, EVs were isolated by SEC. Purer EVs were obtained and proved to maintain the differentiation effect on MSCs and showed a dose-dependent response. Conclusion. PL-derived EVs present an osteogenic capability comparable to PL treatments, emerging as an alternative able to overcome PL and PRP limitations. Cite this article: Bone Joint Res 2020;9(10):667–674


Aims

This study examined whether systemic administration of melatonin would have different effects on osseointegration in ovariectomized (OVX) rats, depending on whether this was administered during the day or night.

Methods

In this study, a titanium rod was implanted in the medullary cavity of one femoral metaphysis in OVX rats, and then the rats were randomly divided into four groups: Sham group (Sham, n = 10), OVX rat group (OVX, n = 10), melatonin day treatment group (OVX + MD, n = 10), and melatonin night treatment group (OVX + MN, n = 10). The OVX + MD and OVX + MN rats were treated with 30 mg/kg/day melatonin at 9 am and 9 pm, respectively, for 12 weeks. At the end of the research, the rats were killed to obtain bilateral femora and blood samples for evaluation.


Bone & Joint Research
Vol. 9, Issue 10 | Pages 709 - 718
1 Oct 2020
Raina DB Liu Y Jacobson OLP Tanner KE Tägil M Lidgren L

Bone is a dynamic tissue with a quarter of the trabecular and a fifth of the cortical bone being replaced continuously each year in a complex process that continues throughout an individual’s lifetime. Bone has an important role in homeostasis of minerals with non-stoichiometric hydroxyapatite bone mineral forming the inorganic phase of bone. Due to its crystal structure and chemistry, hydroxyapatite (HA) and related apatites have a remarkable ability to bind molecules. This review article describes the accretion of trace elements in bone mineral giving a historical perspective. Implanted HA particles of synthetic origin have proved to be an efficient recruiting moiety for systemically circulating drugs which can locally biomodulate the material and lead to a therapeutic effect. Bone mineral and apatite however also act as a waste dump for trace elements and drugs, which significantly affects the environment and human health.

Cite this article: Bone Joint Res 2020;9(10):709–718.


Bone & Joint Research
Vol. 7, Issue 11 | Pages 601 - 608
1 Nov 2018
Hsu W Hsu W Hung J Shen W Hsu RW

Objectives

Osteoporosis is a metabolic disease resulting in progressive loss of bone mass as measured by bone mineral density (BMD). Physical exercise has a positive effect on increasing or maintaining BMD in postmenopausal women. The contribution of exercise to the regulation of osteogenesis in osteoblasts remains unclear. We therefore investigated the effect of exercise on osteoblasts in ovariectomized mice.

Methods

We compared the activity of differentially expressed genes of osteoblasts in ovariectomized mice that undertook exercise (OVX+T) with those that did not (OVX), using microarray and bioinformatics.