Valproic acid attenuates traumatic spinal cord injury-induced inflammation via STAT1 and NF-κB pathway dependent of HDAC3.

BACKGROUND: Microglial polarization with M1/M2 phenotype shifts and the subsequent neuroinflammatory responses are vital contributing factors for spinal cord injury (SCI)-induced secondary injury. Nuclear factor-κB (NF-κB) is considered the central transcription factor of inflammatory mediators, which plays a crucial role in microglial activation. Lysine acetylation of STAT1 seems necessary for NF-kB pathway activity, as it is regulated by histone deacetylases (HDACs). There have been no studies that have explained if HDAC inhibition by valproic acid (VPA) affects the NF-κB pathway via acetylation of STAT1 dependent of HDAC activity in the microglia-mediated central inflammation following SCI. We investigated the potential molecular mechanisms that focus on the phenotypic transition of microglia and the STAT1-mediated NF-κB acetylation after a VPA treatment. METHODS: The Basso-Beattie-Bresnahan locomotion scale, the inclined plane test, the blood-spinal cord barrier, and Nissl staining were employed to determine the neuroprotective effects of VPA treatment after SCI. Assessment of microglia polarization and pro-inflammatory markers, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, and interferon (INF)-γ was used to evaluate the neuroinflammatory responses and the anti-inflammatory effects of VPA treatment. Immunofluorescent staining and Western blot analysis were used to detect HDAC3 nuclear translocation, activity, and NF-κB signaling pathway activation to evaluate the effects of VPA treatment. The impact of STAT1 acetylation on NF-kB pathway and the interaction between STAT1 and NF-kB were assessed to evaluate anti-inflammation effects of VPA treatment and also whether these effects were dependent on a STAT1/NF-κB pathway to gain further insight into the mechanisms underlying the development of the neuroinflammatory response after SCI. RESULTS: The results showed that the VPA treatment promoted the phenotypic shift of microglia from M1 to M2 phenotype and inhibited microglial activation, thus reducing the SCI-induced inflammatory factors. The VPA treatment upregulation of the acetylation of STAT1/NF-κB pathway was likely caused by the HDAC3 translocation to the nucleus and activity. These results indicated that the treatment with the VPA suppressed the expression and the activity of HDAC3 and enhanced STAT1, as well as NF-κB p65 acetylation following a SCI. The acetylation status of NF-kB p65 and the complex with NF-κB p65 and STAT1 inhibited the NF-kB p65 transcriptional activity and attenuated the microglia-mediated central inflammatory response following SCI. CONCLUSIONS: These results suggested that the VPA treatment attenuated the inflammatory response by modulating microglia polarization through STAT1-mediated acetylation of the NF-κB pathway, dependent of HDAC3 activity. These effects led to neuroprotective effects following SCI.

Family participatory clown therapy in venipuncture in hospitalized children: A non-randomized controlled trial.

OBJECTIVE: To explore the effectiveness of family participatory clown therapy in venipuncture in hospitalized children. METHODS: We recruited 104 children aged 3 to 6 years for a non-randomized controlled trial from March to December 2022. All participants required peripheral venepuncture infusions for treatment. The children were assigned to either the control group (n = 52) or the experimental group (n = 52).Standard care was utilized in the control group. In the experimental group, two clown nurses and a parent provided family participatory clown therapy for 35-45 minutes per child before, during, and after venipuncture. We assessed children's pain (FLACC and W-B FPS), anxiety (VAS-A), medical fear (CFS), crying incidence, compliance, parental anxiety (S-AI), and parental satisfaction. RESULTS: At venipuncture, the FLACC score was lower in the experimental group (4.46±2.053) compared to the control group (5.96±2.441), the W-B FPS score was also lower in the experimental group (4.96±2.392) than in the control group (6.35±2.266), with a statistically significant difference (P<0.05).The children in the experimental group had lower levels of anxiety, medical fear, crying, and parental anxiety than the control group. In addition, child compliance and parent satisfaction were higher in the experimental group than in the control group, with statistically significant differences (P<0.05). CONCLUSION: Family participatory clown therapy can reduce pain, anxiety, medical fear, and crying during venipuncture in children. It can also improve venipuncture compliance, reduce parental anxiety, and increase parental satisfaction.

Histone Deacetylase 3 Inhibition Ameliorates Microglia-Mediated Neuro-Inflammation Via the SIRT1/Nrf2 Pathway After Traumatic Spinal Cord Injury.

BACKGROUND: Microglial-induced inflammation plays a crucial role in the pathophysiological process of nervous system injury, however, still lacks effective therapeutic agents. Previously, we discovered that the inhibition of histone deacetylase 3 (HDAC3) exerts anti-inflammatory effects after traumatic spinal cord injury (SCI), whereas little is known about its underlying mechanism. Therefore, the present study aimed to explore the effects and potential mechanisms of HDAC3 on neuroinflammation and microglial function. METHODS: Rats were randomized into 4 groups: sham group, SCI group, SCI + vehicle group, and SCI + RGF966 group. To examine the effect of HDAC3 on neurological deficit after SCI, we gathered data using the Basso Beattie Bresnahan locomotion scale, the inclined plane test, the blood-spinal cord barrier, junction protein expression, and Nissl staining. We also evaluated microglial activation and inflammatory factor levels. Immunofluorescence analysis, immunohistochemical analysis, western blotting, and quantitative real-time polymerase chain reaction were performed to examine the regulation of the Sirtuin 1 (SIRT1)/nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway. RESULTS: The results showed that HDAC3 inhibition significantly ameliorated Basso-Beattie-Bresnahan (BBB) permeability, brain edema, and improved neurological functions and junction protein levels. Additionally, HDAC3 inhibition significantly inhibited microglial activation, thereby reducing the levels of SCI-induced pro-inflammatory factors. Moreover, HDAC3 inhibition dramatically enhanced the expression of SIRT1 and increased both Nrf2 nuclear accumulation and transcriptional activity, thereby increasing downstream heme oxygenase-1 and NAD(P)H quinone oxidoreductase 1 expression. CONCLUSIONS: The results of this study suggest that HDAC3 inhibition protects the spinal cord from injury following SCI by inhibiting SCI-induced microglial activation and the subsequent inflammatory response via SIRT1/Nrf2 signaling pathway, highlighting HDAC3 as a potential therapeutic target for the treatment of SCI.

Experimental investigation of external explosion in the venting process.

Experimental investigations were conducted on the process of combustion and explosion vent in a 200 mm (diameter) x 400 mm (length) vertical cylindrical vessel. When CH(4)-air mixture gases were used and the vent diameter was 55 mm, conditions of Phi (equivalent ratio)=0.8, Phi=1.0 and Phi=1.3 and two ignition positions (at the cylinder center and bottom) were selected. The venting processes and the correlated factors are discussed in this paper.