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Objective To explore the hub genes and the potential targets in the treatment of diabetes with TREM2 mutation-related cognitive dysfunction with bioinformatics analysis. Methods The cases of differential genes (DEGs) of diabetes mellitus and TREM2 mutation-related cognitive dysfunction were obtained respectively by microarray data analysis, the common differential genes were obtained by intersection between the two diseases. GO analysis, KEGG and Reactome pathway analysis were performed on the selected differential genes. The protein-protein interaction(PPI) network was constructed using online database. Finally, the effects of diabetes and TREM2 on spatial learning and memory of mice were detected by water maze, and the expression of hub gene SNAP25 was detected by Western blot. Results In both datasets, 19 genes showed similar changes, mainly enriched in biological processes and pathways related to neurons and metabolism. According to PPI analysis, DNER, GFAP, GRM5 and SNAP25 were identified as hub genes. Trem2 gene knockout aggravated spatial learning and memory impairment in diabetic mice. The expression of SNAP25 in hippocampus of diabetes mice was significantly increased, and then decreased after Trem2 knockout. Conclusions This study identified 19 TREM2-related genes in diabetes with cognitive dysfunction, among which 4 hub genes were found. These results provide a new experimental basis for the treatment of diabetes patients with cognitive impairment.

Objective To explore the expression of triggering receptor expressed on myeloid cells 2 (TREM2) in high-glucose microglia and to investigate the role of TREM2 in the proliferation, migration and phagocytosis of high-glucose microglia. Methods Microglia cells were divided into control group and high-glucose treatment group(67.5 mmol/L glucose, 24 h). The microglia cells were counted and the expression of Iba1 and TREM2 was detected. TREM2 siRNA was transfected to detect the proliferation and migration of microglia. The amyloid β-peptide (Aβ) with a fluorescent tag was added to observe the phagocytosis of Aβ by microglia. Results Compared to normal microglia, the number of microglia significantly decreased after high-glucose treatment (P＜0.001), while the expression of TREM2 and Iba1 markedly increased (P＜0.001). High glucose and TREM2 did not affect the proliferation of microglia. Compared to the normal group, the migration of microglia significantly decreased after high-glucose treatment (P＜0.05) and TREM2 did not affect the migration ability of high-glucose microglia. Compared to the normal group, the phagocytosis of Aβ by microglia significantly decreased in the high-glucose treated group(P＜0.001). Furthermore, TREM2 knockdown further decreased the phagocytosis of Aβ by high-glucose microglia (P＜0.001). Conclusions The expression of TREM2 in microglia significantly increases after high-glucose treatment, which significantly affects phagocytosis of Aβ by microglia.

Objective The role of activin A receptor type 1C(ACVR1C) in white matter remyelination and neurological outcome of mice with ischemic stroke were investigated. Methods Mice were randomly divided into empty virus vector sham operation group, adeno-associated virus(AAV) sham operation group, empty virus vector model group, AAV model group, empty virus vector activin group A and AAV activin group A.Acvr1cflox/flox mice with middle cerebral artery oclusion-reperfusion (MCAO/R) for 1 to 10 days were established. Adeno-associated virus AAV-PDGFRα-cre and AAV-PLP-cre with cre recombinase were injected into the lateral ventricles of the mice. Conditional knockout of Acvr1c on oligodendrocytes and oligodendrocytes. Neurological function score was used to observe the prognosis of neurological function. The expressions of ACVR1C protein and myelin basic protein (MBP) were detected by Western blot. Results With the extension of reperfusion time, activin A improved the behavioral outcome of mice by ACVR1C on oligodendrocytes at day 7 (P＜0.05), and significantly increased the expression of MBP protein in corpus callosum at day 10 (P＜0.05). Conclusions Activin A promotes white matter remyelination and improves outcomes of neurological function of ischemic stroke mice by acting on ACVR1C on oligodendrocytes.

Objective To investigate the regulation and mechanism of Herkinorin preconditioning on NOD-like receptor protein 3 (NLRP3) in brain tissue of transient middle cerebral artery occlusion (tMCAO) rats. Methods Rats were randomly divided into sham operation group (sham), model group (tMCAO) and Herkinorin group (Herkinorin). Before modeling, rats in Herkinorin group were intraperitoneally given Herkinorin (10 mg/kg) once a day for a week. The rats were evaluated by neurologic score, TTC staining, TUNEL staining 24 h after reperfusion. The expression levels of IκBα, p65, p-p65, pro-IL-1β, IL-1β, pro-caspase1, caspase1 p20 and NLRP3 were detected by Western blot. The binding level of IκBα to β-arrestin2 was detected by co-immunoprecipitation (Co-IP). Results Compared with sham group, rats in tMCAO group had higher behavioral score (P＜0.01), increased cerebral infarction percentage and increased cerebral edema rate (P＜0.01). The level of cell apoptosis was increased in ischemic penumbra (P＜0.01). The expression levels of IκBα and p65 were decreased (P＜0.01) and the expression levels of p-p65, IL-1β, caspase1 p20 and NLRP3 were increased in ischemic penumbra (P＜0.01). The binding level of IκBα to β-arrestin2 was decreased in ischemic penumbra (P＜0.01). Compared with tMCAO group, rats in Herkinorin group had lower behavioral score (P＜0.01), lower cerebral infarction percentage and lower cerebral edema rate (P＜0.01). The level of cell apoptosis was decreased in ischemic penumbra(P＜0.01). The expression of IκBα and p65 was increased (P＜0.01) and the expression of p-p65, IL-1β, caspase1 p20 and NLRP3 was decreased in ischemic penumbra (P＜0.01). The binding of IκBα to β-arrestin2 was increased in ischemic penumbra (P＜0.01). Conclusions Herkinorin may negatively regulate NF-κB/NLRP3 pathway to alleviate cerebral ischemia-reperfusion injury of tMCAO rats.

In order to ensure the straightening quality of spindle rod, reduce the labor intensity of workers and improve the working environment of workers, the causes of straightness error and deformation of spindle rod after hot rolling forming, longitudinal cutting forming, heat treatment and manual straightening were analyzed. The method of straightening the spindle rod with the automatic loading and unloading device of the manipulator on the thread rolling machine was adopted. With the method, the spindle rod was placed on the support plate between the two straightening rollers, and the moving roller moved forward, straightened, retreated and returned to the original position along the radial direction, with the spindle rod repeatedly bent and deformed along the axial direction through the spiral groove of the roller to achieve the purpose of straightening. At the same time, the structural characteristics and dimensions of the straightening roller and the support plate were introduced. The experimental results show that the spindle rod is straightened on the thread rolling machine after rough grinding, and the qualified rate is more than 90%; and the rod output reaches 3 000, which creates conditions for intelligent manufacturing of spindle rod.

Abstract Background Extracellular signal-regulated kinase (ERK), one member of the mitogen-activated protein kinase (MAPK) family, has been suggested to regulate a diverse array of cellular functions, including cell growth, differentiation, survival, as well as neuronal plasticity. Recent evidence indicates a role for ERKs in nociceptive processing in both dorsal root ganglion and spinal cord. However, little literature has been reported to examine the differential distribution and activation of ERK isoforms, ERK1 and ERK2, at different levels of pain-related pathways under both normal and pain states. In the present study, quantitative blot immunolabeling technique was used to determine the spatial and temporal expression of ERK1 and ERK2, as well as their activated forms, in the spinal cord, primary somatosensory cortex (SI area of cortex), and hippocampus under normal, transient pain and persistent pain states. Results In naïve rats, we detected regional differences in total expression of ERK1 and ERK2 across different areas. In the spinal cord, ERK1 was expressed more abundantly than ERK2, while in the SI area of cortex and hippocampus, there was a larger amount of ERK2 than ERK1. Moreover, phosphorylated ERK2 (pERK2), not phosphorylated ERK1 (pERK1), was normally expressed with a high level in the SI area and hippocampus, but both pERK1 and pERK2 were barely detectable in normal spinal cord. Intraplantar saline or bee venom injection, mimicking transient or persistent pain respectively, can equally initiate an intense and long-lasting activation of ERKs in all three areas examined. However, isoform-dependent differences existed among these areas, that is, pERK2 exhibited stronger response than pERK1 in the spinal cord, whereas ERK1 was more remarkably activated than ERK2 in the S1 area and hippocampus. Conclusion Taken these results together, we conclude that: (1) under normal state, while ERK immunoreactivity is broadly distributed in the rat central nervous system in general, the relative abundance of ERK1 and ERK2 differs greatly among specific regions; (2) under pain state, either ERK1 or ERK2 can be effectively phosphorylated with a long-term duration by both transient and persistent pain, but their response patterns differ from each other across distinct regions; (3) The long-lasting ERKs activation induced by bee venom injection is highly correlated with our previous behavioral, electrophysiological, morphological and pharmacological observations, lending further support to the functional importance of ERKs-mediated signaling pathways in the processing of negative consequences of pain associated with sensory, emotional and cognitive dimensions.

Abstract Background Strong noxious stimuli cause plastic changes in spinal nociceptive neurons. Intracellular signal transduction pathways from cellular membrane to nucleus, which may further regulate gene expression by critical transcription factors, convey peripheral stimulation. Cyclic AMP-responsive element binding protein (CREB) is a well-characterized stimulus-induced transcription factor whose activation requires phosphorylation of the Serine-133 residue. Phospho-CREB can further induce gene transcription and strengthen synaptic transmission by the activation of the protein kinase cascades. However, little is known about the mechanisms by which CREB phosphorylation is regulated by protein kinases during nociception. This study was designed to use Western blot analysis to investigate the role of mitogen-activated protein (MAP)/extracellular signal-regulated kinase (ERK) kinase (MEK 1/2), PKA and PKC in regulating the phosphorylation of CREB in the spinal cord of rats following intraplantar capsaicin injection. Results We found that capsaicin injection significantly increased the phosphorylation level of CREB in the ipsilateral side of the spinal cord. Pharmacological manipulation of MEK 1/2, PKA and PKC with their inhibitors (U0126, H89 and NPC 15473, respectively) significantly blocked this increment of CREB phosphorylation. However, the expression of CREB itself showed no change in any group. Conclusion These findings suggest that the activation of intracellular MAP kinase, PKA and PKC cascades may contribute to the regulation of phospho-CREB in central nociceptive neurons following peripheral painful stimuli.