A Machine Learning-Based Image Segmentation Method to Quantify In Vitro Osteoclast Culture Endpoints.

Quantification of in vitro osteoclast cultures (e.g. cell number) often relies on manual counting methods.

Evidence that pyrophosphate acts as an extracellular signalling molecule to exert direct functional effects in primary cultures of osteoblasts and osteoclasts.

Extracellular pyrophosphate (PP) is well known for its fundamental role as a physiochemical mineralisation inhibitor. However, information about its direct actions on bone cells remains limited. This study shows that PP decreased osteoclast formation and resorptive activity by ≤50 %.

Hypoxia mimetics restore bone biomineralisation in hyperglycaemic environments.

Diabetic patients have an increased risk of fracture and an increased occurrence of impaired fracture healing. Diabetic and hyperglycaemic conditions have been shown to impair the cellular response to hypoxia, via an inhibited hypoxia inducible factor (HIF)-1α pathway. We investigated, using an in vitro hyperglycaemia bone tissue engineering model (and a multidisciplinary bone characterisation approach), the differing effects of glucose levels, hypoxia and chemicals known to stabilise HIF-1α (CoCl and DMOG) on bone formation.

Modulation of osteoblast differentiation and function by the P2X4 receptor.

Bone cells are known to express multiple P2 receptor subtypes, and the functional effects of receptor activation have been described for many of these. One exception is the P2X4 receptor, which despite strong expression in osteoblasts and osteoclasts, has no defined functional activity. This study used the selective P2X4 receptor antagonists, 5-BDBD and PSB-12062, to investigate the role of this receptor in bone.