Skeletal microenvironment system utilising bovine bone scaffold co-cultured with human osteoblasts and osteoclast-like cells.

A three-dimensional ex vivo bone cell culture system mimicking the skeletal system is useful for bone tissue engineering and as drug discovery platforms. The present study aimed to establish a three-dimensional skeletal culture system using native bovine bone scaffolds and human bone cells. Bovine bone scaffolds were cultured with human foetal osteoblasts 1.19 and human peripheral blood mononuclear cells for 21 days under standard culture conditions. The following groups were established: Decalcified unseeded bone scaffold (DUBS) as baseline control, decalcified seeded bone scaffold (DSBS) to mimic osteoporosis condition and undecalcified seeded bone scaffold to mimic normal condition. The scaffold's porosity and cell attachment on the scaffolds were determined using scanning electron microscopy. Histological evaluation was used to examine changes in trabecular bone structure. Dual-energy X-ray absorptiometry analysis was performed to determine the bone mineral density (BMD) and bone mineral content (BMC) of the scaffolds. A compression test was performed to examine the total biomechanical strength of the scaffolds. The trabecular thickness and number increased, while the trabecular separationwas reduced slightly in DSBS than in DUBS (P>0.05). The BMD and BMC increased significantly (P<0.05), while the compressive strength only increased slightly in DSBS than in DUBS (P>0.05). In conclusion, the ex vivo skeletal microenvironment comprising native bovine bone scaffolds seeded with bone cells is structurally, functionally and mechanically comparable with natural bone. This system may be used as a platform to understand bone physiology and screen for potential drug candidates.

The relationship between circulating testosterone and inflammatory cytokines in men.

Testosterone is the predominant gonadal androgen in men. Low testosterone levels are found to be associated with an increased in metabolic risk and systematic inflammation. Since adipose tissue is a source of inflammatory cytokines, testosterone may regulate inflammation by acting on adipose tissue. This review aimed to explore the role of testosterone in inflammation and its mechanism of action. Both animal studies and human studies showed that (1) testosterone deficiency was associated with an increase in pro-inflammatory cytokines; (2) testosterone substitution reduced pro-inflammatory cytokines. The suppression of inflammation by testosterone were observed in patients with coronary artery disease, prostate cancer and diabetes mellitus through the increase in anti-inflammatory cytokines (IL-10) and the decrease in pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α). Despite these, some studies also reported a non-significant relationship. In conclusion, testosterone may possess anti-inflammatory properties but its magnitude is debatable. More evidence is needed to validate the use of testosterone as a marker and in the management of chronic inflammatory diseases.

Protective Effects of Selected Botanical Agents on Bone.

Osteoporosis is a serious health problem affecting more than 200 million elderly people worldwide. The early symptoms of this disease are hardly detectable. It causes progressive bone loss, which ultimately renders the patients susceptible to fractures. Osteoporosis must be prevented because the associated fragility fractures result in high morbidity, mortality, and healthcare costs. Many plants used in herbal medicine contain bioactive compounds possessing skeletal protective effects. This paper explores the anti-osteoporotic properties of selected herbal plants, including their actions on osteoblasts (bone forming cells), osteoclasts (bone resorbing cells), and bone remodelling. Some of the herbal plant families included in this review are Berberidaceae, Fabaceae, Arecaceae, Labiatae, Simaroubaceaea, and Myrsinaceae. Their active constituents, mechanisms of action, and pharmaceutical applications were discussed. The literature shows that very few herbal plants have undergone human clinical trials to evaluate their pharmacological effects on bone to date. Therefore, more intensive research should be performed on these plants to validate their anti-osteoporotic properties so that they can complement the currently available conventional drugs in the battle against osteoporosis.

Optimization of the Static Human Osteoblast/Osteoclast Co-culture System.

Osteoblasts (OBs) and osteoclasts (OCs) are 2 major groups of bone cells. Their cell-to-cell interactions are important to ensure the continuity of the bone-remodeling process. Therefore, the present study was carried out to optimize an OB/OC co-culture system utilizing the human OB cell line hFOB 1.19 and OCs extracted from peripheral blood mononuclear cells (PBMNCs). It was a 2-step procedure, involving the optimization of the OB culture and the co-culture of the OBs with PBMNCs at an optimum ratio. Firstly, pre-OBs were cultured to 90% confluency and the time required for differentiation was determined. OB differentiation was determined using the van Gieson staining to detect the presence of collagen and Alizarin Red for calcium. Secondly, OBs and OCs were co-cultured at the ratios of 1 OC: 1 OB, 1 OC: 4 OBs, 2 OCs: 1 OB, and 1 OC: 2 OBs. Tartrate-resistant acid phosphatase (TRAP) staining was used to detect the differentiation of the OCs. The results showed that collagen was present on day 1, whereas calcium was detected as early as day 3. Based on the result of TRAP staining, 1 OC: 2 OBs was taken as the most appropriate ratio. No macrophage colony-stimulating factor and receptor activator of the nuclear factor-κB ligand were added because they were provided by the OBs. In conclusion, these optimization processes are vital as they ensure the exact time point and ratio of the OB/OC co-culture in order to produce a reliable and reproducible co-culture system.