Disturbance of neuron-microglia crosstalk mediated by GRP78 in Neuropsychiatric systemic lupus erythematosus mice

ETS1 promotes cisplatin resistance of NSCLC cells by promoting GRP78 transcription

Non-small cell lung cancer (NSCLC) is a common malignant tumor characterized by rapid growth and invasive power. Glucose regulatory protein 78 (GRP78) is important in cancer cell progression. Here, this study aimed to explore the effect and mechanism of GRP78 on cisplatin (DDP) resistance of NSCLC cells. qRT-PCR and Western blot detected the expression of genes and proteins. Flow cytometry was used to analyze endoplasmic reticulum stress (ERS) induced by DDP in NSCLC. Cell proliferation and apoptosis were examined using cell counting kit-8 (CCK8), cell cloning, and flow cytometry, respectively. Chromatin immunoprecipitation assay (CHIP) and dual-luciferase reporter assays were performed to determine the binding of ETS1 and GRP78 promoter. Mouse xenograft models were constructed for in vivo analysis. ERS was induced by DDP in NSCLC cells. GRP78 were upregulated in DDP-resistant NSCLC tissues, and knockdown of GRP78 suppressed DDP resistance, clone formation, promoted apoptosis, and inhibited ERS in DDP-resistant NSCLC cells. ETS1 knockdown repressed GRP78 expression and NSCLC tumor growth. Interestingly, ETS1 played a role in DDP-resistant NSCLC via GRP78. ETS1 inhibits cisplatin sensitivity of NSCLC cells by promoting GRP78 transcription.

CCR3 knockdown attenuates prolonged underwater operations-induced cognitive impairment via alleviating microglia-mediated neuroinflammation

Maintaining cognitive integrity is crucial during underwater operations, which can significantly impact work performance and risk severe accidents. However, the cognitive effects of underwater operations and their underlying mechanism remain elusive, posing great challenges to the medical protection of professionals concerned. Here, we found that a single underwater operation session affects cognition in a time-dependent model. Prolonged exposure elicits significant cognitive impairment and hippocampal dysfunction, accompanied by increased neuroinflammation. Furthermore, RNA sequencing (RNA-seq) analysis revealed the involvement of neuroinflammation and highlighted the critical role of CCR3. Knockdown of CCR3 significantly rescued cognitive impairment and hippocampal dysfunction and reversed the upregulation of pro-inflammatory cytokines, by switching the activated microglia from a pro-inflammatory to a neuroprotective phenotype. Taken together, these results highlighted the time-dependent effects of a single underwater operation session on cognitive function. Knocking down CCR3 can attenuate neuroinflammation by regulating polarization of activated microglia, thereby alleviating prolonged underwater operations-induced cognitive impairment.

Protein tyrosine phosphatase 1B contributes to neuropathic pain by aggravating NF-κB and glial cells activation-mediated neuroinflammation via promoting endoplasmic reticulum stress

BACKGROUND

Neuropathic pain is a prevalent and highly debilitating condition that impacts millions of individuals globally. Neuroinflammation is considered a key factor in the development of neuropathic pain. Accumulating evidence suggests that protein tyrosine phosphatase 1B (PTP1B) plays a crucial role in regulating neuroinflammation. Nevertheless, the specific involvement of PTP1B in neuropathic pain remains largely unknown. This study aims to examine the impact of PTP1B on neuropathic pain and unravel the underlying molecular mechanisms implicated.

METHODS

In the current study, we evaluated the paw withdrawal threshold (PWT) of male rats following spared nerve injury (SNI) to assess the presence of neuropathic pain. To elucidate the underlying mechanisms, western blotting, immunofluorescence, and electron microscopy techniques were employed.

RESULTS

Our results showed that SNI significantly elevated PTP1B levels, which was accompanied by an increase in the expression of endoplasmic reticulum (ER) stress markers (BIP, p-PERK, p-IRE1α, and ATF6) and phosphorylated NF-κB in the spinal dorsal horn. SNI-induced mechanical allodynia was impaired by the treatment of intrathecal injection of PTP1B siRNA or PTP1B-IN-1, a specific inhibitor of PTP1B. Moreover, the intrathecal administration of PTP1B-IN-1 effectively suppressed the expression of ER stress markers (BIP, p-PERK/p-eIF2α, p-IRE1α, and ATF6), leading to the inhibition of NF-κB, microglia, and astrocytes activation, as well as a decrease in pro-inflammatory cytokines, including TNF-α, IL-6, and IL-1β. However, these effects were reversed by intrathecal administration of tunicamycin (Tm, an inducer of ER stress). Additionally, intrathecal administration of Tm in healthy rats resulted in the development of mechanical allodynia and the activation of NF-κB-mediated neuroinflammatory signaling.

CONCLUSIONS

The upregulation of PTP1B induced by SNI facilitates the activation of NF-κB and glial cells via ER stress in the spinal dorsal horn. This, in turn, leads to an increase in the production of pro-inflammatory cytokines, thereby contributing to the development and maintenance of neuropathic pain. Therefore, targeting PTP1B could be a promising therapeutic strategy for the treatment of neuropathic pain.