Lycium barbarum polysaccharide protects against osteonecrosis of femoral head via regulating Runx2 expression.

BACKGROUND: Osteonecrosis of femoral head (ONFH) is a pathological state caused by lack of blood supply in femoral head. This study aimed to explore the function of Lycium barbarum polysaccharide (LBP), an antioxidant agent extracted from L. barbarum, on ONFH. METHODS: Osteonecrosis rat model was generated using lipopolysaccharide (LPS) and methylprednisolone followed by examination of body weight, blood glucose, morphology, and BMSC osteoblast differentiation. The effect and underlying mechanism of LBP on the proliferation, apoptosis, and osteoblast differentiation of BMSC were determined with or without LPS or hypoxia treatment using CCK-8. Alizarin Red S staining, flow cytometry, and western blot, respectively. RESULT: LBP could protect against glucocorticoid-induced ONFH in rats, resulting in improved sparse trabecular bone, empty lacunae and bone cell coagulation. Moreover, LBP promoted the proliferation and osteoblast differentiation of bone mesenchymal-derived stem cells (BMSCs) in a dose-dependent manner. Furthermore, LBP enhanced osteoblast differentiation of BMSCs under hypoxia condition. Mechanistically, we found that LBP treatment enhanced Runx2 and ALP expression in BMSCs. LBP restored the expression of Runx2 and ALP under hypoxia, suggesting that LBP might be involved in regulating Runx2/ALP expression and contributed to osteoblast differentiation. Knockdown of Runx2 significantly inhibited BMSCs proliferation, while LBP treatment did not rescue the osteoblast differentiation ability of BMSCs with Runx2 knockdown. CONCLUSION: Our findings suggested that LBP protects against ONFH via regulating Runx2 expression, which could be utilized to treat patients suffering ONFH.

Clinical application of different operative approach of total knee replacement in knee valgus patients. Retrospective cohort study.

PURPOSE: According to the severity of knee valgus, different operative approaches were applied in total knee replacement. Hence, we assessed the safety and efficacy of different operative approaches in the level IV study. METHODS: From May 2011 to March 2014, a retrospectively analysis was conducted among 31 patients with knee valgus (mild in 10 cases, moderate in 8 cases and severe in 13 cases based on Keblish grade). Medial approach trip knee replacement was performed in mild and moderate patients, which were assigned as medial approach group. Lateral approach was performed in severe patients, which was assigned as lateral approach group. Relevant results were compared between medial approach group and lateral approach group, including valgus corrected angle, postoperative knee joint activity and Kss score. Furthermore, operative time, postoperative blood loss, patellar trajectory and anterior knee pain were also compared between the two groups. RESULTS: All operations were successful without obvious complications. In medial approach group, postoperative knee valgus angle was (7 ±â€¯1)°. Three months after operation, degree of knee joint activity was (85.2 ±â€¯5.2)°, and KSS score of knee joint was (80.1 ±â€¯5.2). Significant differences were detected in these compared with preoperative data (all P < .05). Moreover, similar results were found in lateral approach group with postoperative knee valgus angle as (8.2 ±â€¯2.3)°, degree of knee joint activity three months after operation as (85.2 ±â€¯5.3)°, and KSS score of knee joint as (80.3 ±â€¯3.2). However, no significant differences were found among these three groups in operative time, postoperative blood loss, patellar trajectory or anterior knee pain. CONCLUSIONS: Different operative approaches in total knee replacement according to the severity of knee valgus were proved as effective and safe procedures, which deserved further application.