TOM40 mediates the effect of TSPO on postpartum depression partially through regulating calcium homeostasis in microglia

AIMS

To assess the effect of the translocator protein 18 kDa (TSPO) on postpartum depression and explore its mechanism.

METHODS

Postpartum depression (PPD) mouse model was established, and flow cytometry, immunofluorescence, Western blot analysis, real-time quantitative PCR, adeno-associated virus (AAV), co-immunoprecipitation-mass spectrometry and immunofluorescence co-staining were used to detect the effect of TSPO ligand ZBD-2 on PPD mice.

RESULTS

ZBD-2 inhibits the overactivation of microglia in the hippocampus and amygdala of PPD model mice. ZBD-2 not only inhibited the inflammation but also repressed the burst of reactive oxygen species (ROS) and mitochondrial ROS (mtROS). Meanwhile, ZBD-2 protects mitochondria from LPS-induced damages through inhibiting the influx of calcium. ZBD-2 modulated the calcium influx by increasing the level of translocase of the outer mitochondrial membrane 40 (TOM40) and reducing the interaction of TSPO and TOM40. In addition, the effect of ZBD-2 was partially dependent on anti-oxidative process. Knockdown of TOM40 by adeno-associated virus (AAV) in the hippocampus or amygdala dramatically reduced the effect of ZBD-2 on PPD, indicating that TOM40 mediates the effect of ZBD-2 on PPD.

CONCLUSIONS

TOM40 is required for the effect of ZBD-2 on treating anxiety and depression in PPD mice. This study reveals the role of microglia TSPO in PPD development and provides the new therapeutic strategy for PPD.

[Effectiveness of TRB3 on human hepatocellular carcinoma cells proliferation, apoptosis and migration]

Objective: To explore the regulatory role and mechanism of tribbles pseudokinase 3 (TRB3) on hepatocarcinoma (HCC) cells proliferation, apoptosis and migration. Methods: Immunohistochemistry and Western blot were used to detect TRB3 expression in cancerous and adjacent cancerous liver tissues of HCC patients. TRB3 expression was detected in vitro in HepG2 and Huh7 hepatocarcinoma cell lines. Simultaneously, CCK8 and EdU were used to detect cell proliferation after TRB3 targeted inhibition with small interfering RNA. CCK8 and EdU were used to detect cell proliferation. Flow cytometry assay was used to detect apoptosis. Transwell assay was used to evaluate migration ability. Simultaneously, Western blot was used to detect changes in apoptosis, migration-related proteins and AKT phosphorylation activity. The mean comparison between the two groups was performed by t-test, and the comparison between multiple groups was performed by one-way analysis of variance. Results: Western blot showed that the expression of TRB3 was significantly up-regulated in HCC tissues. Compared with normal liver tissues adjacent to cancer, the relative expression levels were 0.78 ± 0.12 and 0.29 ± 0.09, respectively, P < 0.01, and the difference was statistically significant. After interfering siRNA inhibited TRB3, CCK8 and EdU tests showed that the proliferation activity of HepG2 and Huh7 cells were significantly weakened (P < 0.05). Flow cytometry results showed that the apoptotic proportions of HepG2 and Huh7 cells was significantly increased (P < 0.01). Western blot also showed that the expression of apoptosis regulatory proteins BAX and BIM were significantly increased (P < 0.01). Transwell assay results showed that the migration ability of HepG2 and Huh7 cells was decreased (P < 0.05), and the expression of migration regulatory proteins MMP4 and MMP9 was also significantly down-regulated. Western blot results showed that the AKT phosphorylation level was significantly increased. Conclusion: TRB3 regulates hepatocarcinoma cells proliferation, apoptosis and migration by inhibiting the AKT phosphorylation activity. Therefore, TRB3 may be a potential target site for the liver cancer treatment.

Quaking Deficiency Amplifies Inflammation in Experimental Endotoxemia via the Aryl Hydrocarbon Receptor/Signal Transducer and Activator of Transcription 1-NF-κB Pathway

Macrophages, characterized by considerable diversity and plasticity, play a crucial role in a broad spectrum of biological processes, including inflammation. However, the molecular mechanisms underlying the diverse phenotypes of macrophages are not well defined. Here, we show that the RNA-binding protein, quaking (QKI), dynamically modulates macrophage polarization states. After lipopolysaccharide (LPS) stimulation, QKI-silenced RAW 264.7 cells displayed a pro-inflammatory M1 phenotype characterized by increased expression of iNOS, TNF-α, and IL-6 and decreased expression of anti-inflammatory factors, such as IL-10, found in inflammatory zone (Fizz1), and chitinase-like 3 (Chil3 or Ym1). By contrast, QKI5 overexpression led to a suppressive phenotype resembling M2 macrophages, even under M1 differentiation conditions. Moreover, myeloid-specific QKI-deficient mice tended to be more susceptible to LPS-induced endotoxic shock, while the exogenous transfer of macrophages overexpressing QKI5 exerted a significant improving effect. This improvement corresponded to a higher proportion of M2 macrophages, in line with elevated levels of IL-10, and a decrease in levels of pro-inflammatory mediators, such as IL-6, TNF-α, and IL-1β. Further mechanistic studies disclosed that QKI was a potent inhibitor of the nuclear factor-kappa B (NF-κB) pathway, suppressing p65 expression and phosphorylation. Strikingly, reduced expression of the aryl hydrocarbon receptor (Ahr) and reduced phosphorylation of signal transducer and activator of transcription 1 in QKI-deficient cells failed to restrain the transcriptional activity of NF-κB and NRL pyrin domain containing 3 (NLRP3) activation, while restoring QKI expression skewed the above M1-like response toward an anti-inflammatory M2 state. Taken together, these findings suggest a role for QKI in restraining overt innate immune responses by regulating the Ahr/STAT1–NF-κB pathway.

[Heart morphologic state in retired fighter pilots]

Objective. To study the heart morphology in the retired fighter pilots, and to provide clinical evidence for protection combined G-loads (+ Gz), heat, noise, hypoxic and vibration stress induced cardiac structural damage. Method. Parameters of heart morphology were studied using Doppler echocardiography in 40 retired fighter pilots with 40 veteran cadres as control. Result. LVDd, LVDs, LADs, LVEDV, LVPWs and LVM in pilot group were somewhat higher than those in control group (NS); while IVSs and LVMI in pilot group were slightly lower than those in control group (NS); LVESV, aortic valve area, internal diameter of the ring and sinus in pilot group were significantly higher than those in control group (P < 0.05). Conclusion. Analysis of the results revealed no pathomorphologic damage of the heart. It suggest that all the variations can be regarded as adaptive changes due to the effects of the combined environmental factors experienced in long time flying.