Bone
-
Radiation of the hip is an established method to prevent heterotopic ossification (HO) following total hip arthroplasty (THA) but the precise mechanism is unclear. As inflammatory processes are suggested to be involved in the pathogenesis of HO, we hypothesized that the preoperative irradiation impacts local immune components. Therefore, we quantified immune cell populations and cytokines in hematomas resulting from the transection of the femur in two groups of patients receiving THA: patients irradiated preoperatively (THA-X-hematoma: THA-X-H group) in the hip region (7 Gy) in order to prevent HO and patients who were not irradiated (THA-H group) but were postoperatively treated with non-steroidal anti-inflammatory drugs (NSAIDs). ⋯ In contrast, the concentration of the angiogenic VEGF was significantly suppressed in the THA-X-H group. We conclude that preoperative irradiation results in significant changes in immune cell composition and cytokine secretion in THA-hematomas, establishing a specific - rather proinflammatory - milieu. This increase of inflammatory activity together with the observed suppression in VEGF secretion may contribute to the prevention of HO.
-
Epimedium-derived flavonoids (EFs) have a potential to treat established osteoporosis in postmenopausal women. However, one of the main disadvantages of the compound is the high volume and dosage during long-term administration period. Meanwhile, the beneficial effect of EFs on osteoporotic bone depends greatly on the intervention timing. Whether icaritin (ICT), an active molecular compound from EFs, can exert beneficial effect on osteoporotic bone and whether the beneficial effect is also dependent on the intervention timing remain unknown. ⋯ ICT can exert anabolic and anti-resorptive effect on osteoporotic bone. The beneficial effect of ICT treatment is dependent on the intervention timing in established osteoporosis induced by estrogen depletion.