Résumé
Objective:To investigate the role of Sestrin2 overexpression in regulating mitochondrial fission and its mechanism in human neuroblastoma SH-SY5Y cell model of glucose and oxygen deprivation/recovery (OGD/R). Methods:(1) SH-SY5Y cells were divided into normal control group, OGD/R group, Vector group, and Sestrin2 overexpression group; Sestrin2 overexpression or empty vector stable cell lines in the Sestrin2 overexpression group and Vector group were constructed by lentivirus infection; cells in the later 3 groups were subjected to oxygen-glucose deprivation (OGD) for 4 h followed by restoration of O 2 supply for 18 h. The cell survival rate was detected by cell counting kit (CCK)-8 assay. The protein levels of Sestrin2, dynamin-related protein 1 (Drp1), mitochondrial fission protein 1 (Fis1), B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), Kelch-like ECH-related protein 1 (Keap1) in the cytoplasm and nuclear factor E2-related factor (Nrf2) in the nucleus were detected by Western blotting. The mitochondria ultrastructure was observed by transmission electron microscope. The Nrf2 nuclear translocation was detected by immunofluorescence staining. (2) Cell lines with Sestrin2 overexpression were divided into Sestrin2 overexpression group, Brusatol+ Sestrin2 overexpression group, and DMSO+ Sestrin2 overexpression group. Cells in the Brusatol+ Sestrin2 overexpression group were pretreated with normal medium containing Brusatol (Keap1/Nrf2 pathway inhibitor, final concentration: 100 nmol/L) for 4 h before OGD/R; cells in the DMSO+ Sestrin2 group were pretreated with normal medium containing DMSO (final volume fraction: 0.1%) for 4 h before OGD/R. Cells in these groups were then subjected to OGD for 4 h followed by restoration of O 2 supply for 18 h. The protein levels of Drp1, Fis1, Keap1 in the cytoplasm, and Nrf2 in the nucleus were measured by Western blotting. Results:(1) As compared with those in the OGD/R group, cells in the Sestrin2 overexpression group had significantly increased survival rate (61.33%±1.15% vs. 81.00%±3.00%), significantly up-regulated Bcl-2/Bax ratio (0.467±0.006 vs. 0.880±0.010), significantly decreased Drp1, Fis1 and cytoplasmic Keap1 protein levels (1.089±0.033 vs. 0.865±0.014; 0.829±0.009 vs. 0.350±0.007; 0.967±0.017 vs. 0.881±0.024), and significantly up-regulated nuclear Nrf2 protein level (0.627±0.025 vs. 0.957±0.015, P<0.05). The mitochondrial structure in the Sestrin2 overexpression group under electron microscope was more complete than that in the OGD/R group, and obvious nuclear translocation of Nrf2 was noted. (2) As compared with the Sestrin2 overexpression group, Brusatol+ Sestrin2 overexpression group had significantly decreased nuclear Nrf2 protein level (0.920±0.013 vs. 0.627±0.035), and statistically increased Drp1 and Fis1 protein levels (0.994±0.020 vs. 1.084±0.005; 0.728±0.010 vs. 0.906±0.022, P<0.05). Conclusion:Sestrin2 overexpression could suppress mitochondrial fission, reduce cell apoptosis, and attenuate OGD/R injury of SH-SY5Y cells by activating Keap1/Nrf2 pathway via down-regulating cytoplasmic Keap1 protein level and promoting Nrf2 nuclear translocation.
Résumé
Objective:To evaluate the effect of dual-tube epidural segmental injection of lidocaine analgesia on the delivery outcome and maternal and infant complications of persistent posterior occipital position postpartum or lateral occipital position postpartum patients with protracted active phase.Methods:The full and single-term primiparas ( n=216, 37 to 42 weeks gestation, 22 to 35 years) diagnosed as persistent posterior or lateral occipital position during the active period were selected from the Department of Obstetrics of Qingdao Municipal Hospital from January 2015 to October 2019. The subjects were randomly assigned into two groups: double-tube epidural block group ( n=108) and single-tube epidural block group ( n=108), 1% lidocaine was used for epidural analgesia respectively under ultrasound guidance. Senior midwife or obstetricians implement new partogram, and guide women to perform position management, and push or rotate the fetal head in a timely manner. Observation indicators: general condition, the use of non-pharmacological analgesic measures, analgesia related conditions and pain visual analogue scale (VAS) score, delivery-related indicator, cesarean section indication, anesthesia-related indicator, maternal and child complications. Results:(1) General condition: the age, weight, height, gestational age, the ratio of persistent lateral or posterior occipital position, cephalic score, and neonatal birth weight between the two groups of women were not statistically significant (all P>0.05). (2) The use of non-pharmacological analgesic measures: the women’s Lamaze breathing method, Doula delivery companionship, percutaneous electrical stimulation, and other measures between two groups were compared, and there were not significant differences (all P>0.05). (3) Analgesia related conditions and VAS scores of women undergoing vaginal delivery: compared with the single-tube epidural block group ( n=40), the second-partum time of the women in the double-tube epidural block group ( n=59) was significantly shortened [(124±44) vs (86±33) minutes, P<0.01]; after 30 minutes of analgesia (4.4±0.5 vs 0.9±0.5, P<0.01), during forced labor in the second stage of labor (5.7±0.6 vs 1.3±0.4, P<0.01), the VAS scores of pain were also significantly reduced ( P<0.01). (4) Labor-related indicators: compared with the single-tube epidural block group, the natural delivery rate (21.3% vs 49.1%) and the delivery experience satisfaction rate (51.9% vs 98.1%) of women in the double-tube epidural block group were significantly increased (all P<0.01), cesarean section rate (63.0% vs 45.4%), instrument assisted rate (15.7% vs 5.6%) decreased significantly (all P<0.05). (5) Cesarean section indications: compared with the single-tube epidural block group, the cesarean section rate caused by prolonged labor or protracted active phase of women in the double-tube epidural block group was significantly reduced (38.0% vs 22.2%； P<0.05), and the fetal distress, intrauterine infection, and social factors caused by cesarean section between the two groups were compared, while the differences were not statistically significant (all P>0.05).(6) Anesthesia related indexes: the block planes of the maternal upper tube administration in the double-tube epidural block group were mostly T7, T8, T9-L2 and L3,While,the block planes in the single-tube epidural block group were mostly T10, T11-S1, S2, S3, and the modified Bromage score were all 0. (7) Maternal and child complications: compared with the single-tube epidural block group, the postpartum hemorrhage rate (18.5% vs 7.4%), the perineal lateral cut rate (20.4% vs 5.6%), the neonatal asphyxia rate (12.0% vs 3.7%), ICU rate of transferred neonates (13.9% vs 4.6%) in the double-tube epidural block group were significantly reduced (all P<0.05). Soft birth canal injury rate, puerperal disease rate and neonatal birth rate between two groups were compared, and there were not statistically significant differences (all P>0.05). Conclusion:Dual-tube epidural segmental injection of lidocaine analgesia could increase the natural delivery rate of women with posterior occipital or lateral occipital position with active stagnation, reduce the rate of cesarean section and the rate of transvaginal instruments, and reduce the complications of mother and child.