MicroRNA-23a reduces lipopolysaccharide-induced cellular apoptosis and inflammatory cytokine production through Rho-associated kinase 1/sirtuin-1/nuclear factor-kappa B crosstalk / 中华医学杂志(英文版)

BACKGROUND@#MicroRNAs are closely associated with the progression and outcomes of multiple human diseases, including sepsis. In this study, we examined the role of miR-23a in septic injury.@*METHODS@#Lipopolysaccharide (LPS) was used to induce sepsis in a rat model and H9C2 and HK-2 cells. miR-23a expression was evaluated in rat myocardial and kidney tissues, as well as H9C2 and HK-2 cells. A miR-23a mimic was introduced into cells to identify the role of miR-23a in cell viability, apoptosis, and the secretion of inflammatory cytokines. Furthermore, the effect of Rho-associated kinase 1 (ROCK1), a miR-23a target, on cell damage was evaluated, and molecules involved in the underlying mechanism were identified.@*RESULTS@#In the rat model, miR-23a was poorly expressed in myocardial (sham vs. sepsis 1.00 ± 0.06 vs. 0.27 ± 0.03, P < 0.01) and kidney tissues (sham vs. sepsis 0.27 ± 0.03 vs. 1.00 ± 0.06, P < 0.01). Artificial overexpression of miR-23a resulted in increased proliferative activity (DNA replication rate: Control vs. LPS vs. LPS + Mock vs. LPS + miR-23a: H9C2 cells: 34.13 ± 3.12 vs. 12.94 ± 1.21 vs. 13.31 ± 1.43 vs. 22.94 ± 2.26, P < 0.05; HK-2 cells: 15.17 ± 1.43 vs. 34.52 ± 3.46 vs. 35.19 ± 3.12 vs. 19.87 ± 1.52, P < 0.05), decreased cell apoptosis (Control vs. LPS vs. LPS + Mock vs. LPS + miR-23a: H9C2 cells: 11.39 ± 1.04 vs. 32.57 ± 2.29 vs. 33.08 ± 3.12 vs. 21.63 ± 2.35, P < 0.05; HK-2 cells: 15.17 ± 1.43 vs. 34.52 ± 3.46 vs. 35.19 ± 3.12 vs. 19.87 ± 1.52, P < 0.05), and decreased production of inflammatory cytokines, including interleukin-6 (Control vs. LPS vs. LPS + Mock vs. LPS + miR-23a: H9C2 cells: 59.61 ± 5.14 vs. 113.54 ± 12.30 vs. 116.51 ± 10.69 vs. 87.69 ± 2.97 ng/mL; P < 0.05, F = 12.67, HK-2 cells: 68.12 ± 6.44 vs. 139.65 ± 16.62 vs. 143.51 ± 13.64 vs. 100.82 ± 9.74 ng/mL, P < 0.05, F = 9.83) and tumor necrosis factor-α (Control vs. LPS vs. LPS + Mock vs. LPS + miR-23a: H9C2 cells: 103.20 ± 10.31 vs. 169.67 ± 18.84 vs. 173.61 ± 15.91 vs. 133.36 ± 12.32 ng/mL, P < 0.05, F = 12.67, HK-2 cells: 132.51 ± 13.37 vs. 187.47 ± 16.74 vs. 143.51 ± 13.64 vs. 155.79 ± 15.31 ng/mL, P < 0.05, F = 9.83) in cells. However, ROCK1 was identified as a miR-23a target, and further up-regulation of ROCK1 mitigated the protective function of miR-23a in LPS-treated H9C2 and HK-2 cells. Moreover, ROCK1 suppressed sirtuin-1 (SIRT1) expression to promote the phosphorylation of nuclear factor-kappa B (NF-κB) p65, indicating the possible involvement of this signaling pathway in miR-23a-mediated events.@*CONCLUSION@#Our results indicate that miR-23a could suppress LPS-induced cell damage and inflammatory cytokine secretion by binding to ROCK1, mediated through the potential participation of the SIRT1/NF-κB signaling pathway.

Correlation between cytochrome 3A4+894C>T P450 gene polymorphism and outcomes of coronary intervention in patients with acute coronary syndrome / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the relationship between plasma cytochrome P450 3A4 (CYP3A4) 894C>T gene polymorphism and the risk of recurrence of adverse cardiac events after percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS).</p><p><b>METHODS</b>A total of 275 patients with ACS received standard dual antiplatelet therapy and PCI. Platelet aggregation rate (PAR) was detected in each patient before and 7 days after administration of the anti-platelet drugs. Single nucleotide polymorphism of CYP3A4 gene 894C>T was detected with PCR and microarray technique. The number of coronary artery lesions was determined by PCI and the Gensini score was calculated. The patients were followed up for 3-12 months after discharge.</p><p><b>RESULTS</b>No significant difference was found in CYP3A4 gene polymorphism between patients with clopidogrel resistance (CR group) and those without CR (NCR group) (P>0.05). Multivariate logistic regression analysis showed that CYP3A4 gene 894C>T polymorphism was not correlated with CR in patients with ACS (OR 1.359, P>0.05). During the follow-up, the incidence of cardiovascular events was significantly higher in CR group than in NCR group (P<0.05), but this difference was not related to the mutation type of 894C>T locus of CYP3A4 gene.</p><p><b>CONCLUSION</b>The CYP3A4 gene 894C>T polymorphism is not associated with the effect of anti-platelet therapy and the risk of cardiovascular event in patients with ACS following PCI.</p>

Periacetabular stress distributions during normal gait cycle and its guiding function in acetabular reconstruction of THA / 医用生物力学

Objective To study the basic regular patterns of stress distributions inside and outside periacetabular districts during normal gait cycle of healthy adults, so as to provide clinical guidance for acetabular reconstruction of total hip arthroplasty (THA). Methods Based on CT scans of a male and a female healthy adult volunteer, The three-dimensional model including pelvis and proximal femur was reconstructed. By using an inhomogeneous material distribution scheme which was based on CT data to calculate elastic modulus and convergence analysis, each element was given a corresponding material attribute. The dynamic change of hip contact force during a normal gait cycle was used as the load condition to the model. Von Mises stress of the nodes inside and outside the model was considered as the criterion to assess the results. Results During normal gait, the stress on the hip surface of two volunteers was mainly transmitted from postersuperior part of acetabulum to auricular surface along posterolateral of iliac wing, and the maximum stress was at the district near greater sciatic. As for the superior, middle and inferior section of two volunteers' acetabulum, the stress was distributed both on cortical and cancellous bone of postersuperior part. However, in terms of acetabular anterior and posterior column, the stress distribution was mainly found on cortical bone. Conclusions According to the observed acetabular stress distribution pattern of health adults during normal gait cycle, choosing acetabular component with more suitable size and controlling the placement of acetabular component with more accuracy could obtain some acetabular reconstruction plan better in accordance with stress distributions during normal gait.

Influence from acetabular component orientation on stress distributions of periacetabulum / 医用生物力学

Abstract： Objective To study the influence from different placement angles of acetabular component on inner and outer stress distributions of periacetabulum in acetabular reconstruction of total hip arthroplasty (THA), so as to explore proper orientation for improving stability of acetabular component after THA. Methods Based on model with inhomogeneous material property assignment, nine THA models with acetabular component at different anteversion angles(15°, 20°, 25°) and abduction angles(40°, 45°, 50°) as well as one normal hip model were constructed. The maximal hip contact force in phase of single leg stance during normal gait cycle was chosen as the loading condition. In addition, according to the qualitative and quantitative principle, inner and outer stress distributions on 9 THA models were analyzed and compared with the normal hip model as control. Results When abduction angle of acetabular component was the nearest to anatomic angle (19° anteversion, 46° abduction) of acetabulum, the phenomenon of stress shielding on periacetabulum was the most obvious. When abduction angle of acetabular component was placed at 45° and anteversion angle changed from 15° to 25°, no significant influence was exerted on the whole stress distributions of THA models. Meanwhile, when anteversion angle of acetabular component was 15°, the THA model had good stability in stress distributions, and the phenomenon of stress shielding on cortical and cancellous bone was obviously improved. Conclusions For patients who have normal anatomic acetabulum and need to be treated with THA, the abduction angle of acetabular component should be placed at 45°, as that of normal acetabulum; the anteversion angle should be 5° smaller than that of normal acetabulum and between 15° and 20°.

Expression of Gluc-Fluc dual luciferase plasmid after transfection into MB49 bladder cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the expression characteristics of Gluc-Fluc dual luciferase plasmid after its transfection into MB49 bladder cells.</p><p><b>METHODS</b>pAAV2neoCAG-Gluc-2A-Fluc and pAAV2neo-Gluc plasmids were separately transfected into MB49 cells via LipofectamineTM2000. The Gluc activity in the cell culture supernatant and the Fluc activity in the cells were detected by luminometer and Lumina Imaging system.</p><p><b>RESULTS</b>The luminometer result showed that the activity of Gluc in the supernatant increased gradually in a cell number- and time-dependent manner, while Fluc activity in the cells increased with the cell number but not with time. The Lumina Imaging system showed that Gluc-Fluc was successfully expressed in MB49 bladder cells and cell lines with stable Gluc-Fluc expression were obtained after G418 selection.</p><p><b>CONCLUSION</b>Gluc in the dual luciferase plasmid retains its expression characteristics. Due to the advantages of Fluc in localization in living imaging and the easy quantitative detection of Gluc, the dual luciferase plasmid, after transfection in MB49 bladder cells, allows reliable and dynamic detection of tumor growth in animal models.</p>