BCL6 attenuates hyperoxia-induced lung injury by inhibiting NLRP3-mediated inflammation in fetal mouse.

BACKGROUND: The transcriptional repressor B-cell lymphoma 6 (BCL6) has been reported to inhibit inflammation. So far, experimental evidence for the role of BCL6 in bronchopulmonary dysplasia (BPD) is lacking. Our study investigated the roles of BCL6 in the progression of BPD and its downstream mechanisms. METHODS: Hyperoxia or lipopolysaccharide (LPS) was used to mimic the BPD mouse model. To investigate the effects of BCL6 on BPD, recombination adeno-associated virus serotype 9 expressing BCL6 (rAAV9-BCL6) and BCL6 inhibitor FX1 were administered in mice. The pulmonary pathological changes, inflammatory chemokines and NLRP3-related protein were observed. Meanwhile, BCL6 overexpression plasmid was used in human pulmonary microvascular endothelial cells (HPMECs). Cell proliferation, apoptosis, and NLRP3-related protein were detected. RESULTS: Either hyperoxia or LPS suppressed pulmonary BCL6 mRNA expression. rAAV9-BCL6 administration significantly inhibited hyperoxia-induced NLRP3 upregulation and inflammation, attenuated alveolar simplification and dysregulated angiogenesis in BPD mice, which were characterized by decreased mean linear intercept, increased radical alveolar count and alveoli numbers, and the upregulated CD31 expression. Meanwhile, BCL6 overexpression promoted proliferation and angiogenesis, inhibited apoptosis and inflammation in hyperoxia-stimulated HPMECs. Moreover, administration of BCL6 inhibitor FX1 arrested growth and development. FX1-treated BPD mice exhibited exacerbation of alveolar pathological changes and pulmonary vessel permeability, with upregulated mRNA levels of pro-inflammatory cytokines and pro-fibrogenic factors. Furthermore, both rAAV9-BCL6 and FX1 administration exerted a long-lasting effect on hyperoxia-induced lung injury (≥4 wk). CONCLUSIONS: BCL6 inhibits NLRP3-mediated inflammation, attenuates alveolar simplification and dysregulated pulmonary vessel development in hyperoxia-induced BPD mice. Hence, BCL6 may be a target in treating BPD and neonatal diseases.

[Clinical observation of improved proximal femoral locking plate in treating osteoporotic intertrochanteric fractures].

OBJECTIVE: To investigate the effects of proximal femoral locking plate (PFP) in treating osteoporotic intertrochanteric fractures and to analyze the failure cases. METHODS: Totally 32 patients with osteoporotic intertrochanteric fractures of Evans I and II were treated with improved locking PFP, including 17 males and 15 females with an average age of 77.3 years old ranging from 70 to 86 years old. After operation, according to Harris hip scores, the hip function and therapeutic effects were evaluated. RESULTS: The observed 32 patients' operative time was (60.5±15.7) min, intraoperative blood loss was (128.8±73.6) ml;perioperative blood transfusion was (224.0±72.7) ml. Hospitalization time was from 14 to 20 d with an average of 17.2 d. All patients were followed up from 6 to 18 months with an average of 14.1 months. The fracture healing time was from 3 to 6 months with an average of 3.1 months. One patient occurred internal fixation loosening and screw backward, 4 cases occurred urinary tract infection, 1 patient died of cardiovascular disease for 6 months postoperative, 2 patients died of a stroke for 1 year postoperative. No incision deep infection, peri internal fixation fractures, lower extremity deep venous thrombosis, internal fixation breakage, nonunion, severe coax vara and coax valgus occurred. The final Harris score was 89.74±6.84, the result was excellent in 10 cases, good in 16 cases, fair in 4 cases, and poor in 2 cases. CONCLUSIONS: Locking PFP can provide relative stable fixation to proximal end of osteoporotic femoral fractures, which is a good choice for the treatment of intertrochanteric fractures. It could provide stableness of fractures and bone union, even avoid screws loose or slide out.