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Background: The purpose of this study was to investigate the potential involvement of pyruvate kinase M2 (PKM2), an enzyme acting as a rate-limiting enzyme in the final phase of glycolysis, in the regulation of glial activation and brain damage of intracerebral hemorrhage (ICH). Methods: Western blotting and immunofluorescence were performed to investigate PKM2 expression, terminal deoxynucleotidyl transferase deoxyurinary triphosphate (dUTP) nick end labeling staining, hematoxylin and eosin staining, and behavioral tests were employed to evaluate the brain damage of ICH mice, and RNA-seq and bioinformatic analyses were performed to detect gene expression changes in ICH mice treated with TEPP-46. Results: Increased PKM2 levels in perihematomal brain tissue were found starting from 3 days following ICH and peaked at 5 and 7 days post ICH. The increased expression of PKM2 was mainly co-localized with glial fibrillary acidic protein (GFAP)+ astrocytes and ionized calcium binding adaptor molecule-1 (IBA-1)+ microglia. Furthermore, we observed a notable increase in the nuclear translocation of PKM2 in glial cells following ICH. TEPP-46 treatment significantly reduced PKM2 nuclear translocation, and effectively attenuated glial activation and brain injury, and improved functional recovery of mice with ICH. RNA-seq data indicated that 91.1% (205/225) of differentially expressed genes (DEGs) were down-regulated in the TEPP-46 treated groups compared with the vehicle-treated groups in ICH brains. Furthermore, bioinformatic analyses revealed that these down-regulated DEGs were involved in a variety of biological processes, including autophagy and metabolic processes. In addition, the majority of these downregulated DEGs had a primary high expression in neurons, with subsequent expression seen in endothelial cells, microglia, and astrocytes. Conclusions: These results indicate that increased PKM2 nuclear translocation promotes the activation of glial cells after ICH, hence aggravating ICH-induced brain damage, and aggravates the brain injury induced by ICH. This highlights a potential therapeutic target for inhibiting glial activation to attenuate brain injury after ICH. [ABSTRACT FROM AUTHOR]

• This study proposed a novel kind of wet joint with UHPC shear keys to connect prefabricated composite beams. • The effects of different parameters for UHPC shear key on strengthening shear performances of wet joints were investigated. • The failure mechanism of novel UHPC shear key joints was clarified in detail. • The calculation formulas considering different factors were established to design and optimize the prefabricated composite beams. Ultra-high-performance concrete (UHPC) has excellent mechanical properties, which could be used in the connecting region between different prefabricated members to improve the continuity and integrity of prefabricated composite structures. In this paper, a novel kind of wet joint with UHPC shear key was proposed to connect different prefabricated components for assembled steel–concrete composite beams, and the effects of different parameters for UHPC shear key on strengthening shear performances of wet joints were evaluated via a series of push-out tests. Results indicated that the specimens with wet joints mainly failed and slipped in the precast and post-cast concrete interface under the longitudinal force. The application of the UHPC shear key could significantly increase the ultimate shear strength of the interface compared to the single layer of extended reinforcements, and the UHPC shear key with embedded short reinforcements could further improve the shear resistance and ductility to ensure the composite action between the precast slab and wet joint. Compared with the dual layers of extended reinforcements, the combination of the UHPC shear key and short straight steel bar presented a better performance in strength under a relatively lower slip level. In addition, the increase in width was helpful for enhancing the shear strength of the UHPC shear key, but the shear keys with the larger width might cause the failure of the precast part between two UHPC shear keys prior to the UHPC shear keys so limiting the strength development of interface, thus the reasonable design size of the shear key should be selected depending on the precast and post-cast concrete strength. Furthermore, an equation for the wet joint with UHPC shear key was proposed, which considered the proportion of effects of different factors such as the interface bonding strength, interface friction, extended reinforcement, negative bending moment, UHPC shear key and embedded short straight steel bar on the longitudinal shear behavior of UHPC wet joints. [ABSTRACT FROM AUTHOR]