NIR, a novel INHAT, negatively regulates the transcription activity of tumor repressor p53. However, if NIR functions in the tumorigenesis dependent on the regulation of p53 remains unknown. Here, we report that NIR promotes progression of colorectal cancer (CRC) through regulating RB function. Firstly, we found that NIR expression is upregulated in the human CRC tissues and significantly associated with the poor outcome of the patients. Sequence alignment shows that NIR contains an RB-binding motif LxCxE in its INHAT-2 domain. We demonstrate that NIR interacts with RB via INHAT-2 in CRC cells and promotes RB degradation through proteasome-mediated pathway. Further, either full-length GFP-NIR or GFP-NIR-INHAT2 facilitates poly-ubiquitination of RB. In addition, NIR inhibits RB acetylation by INHAT-2, suggesting NIR might promote RB degradation through inhibiting RB acetylation. Importantly, endogenous NIR is downregulated upon DNA damage, which is consistent with the upregulation of total level and acetylation of RB. We further show that Flag-NIR inhibits DNA damage-induced RB acetylation. https://www.selleckchem.com/products/i-bet-762.html Thus, downregulation of NIR might contribute to maintain the cellular homeostasis under DNA damage. Consequently, depletion of NIR inhibits cell proliferation and tumor growth in mouse xenografts. Taken together, we demonstrate that NIR promotes CRC progression partially through inhibiting RB acetylation and promoting RB degradation. Targeting NIR may provide a potential therapeutic strategy for NIR-upregulated CRC patients.Despite persistent clinical use for over 170 years, the neuronal mechanisms by which general anesthetics produce hypnosis remain unclear. Previous studies suggest that anesthetics exert hypnotic effects by acting on endogenous arousal circuits. Recently, it has been shown that the medial parabrachial nucleus (MPB) is a novel wake-promoting component in the dorsolateral pons. However, it is not known whether and how the MPB contributes to anesthetic-induced hypnosis. Here, we investigated the action of sevoflurane, a widely used volatile anesthetic agent that best represents the drug class of halogenated ethers, on MPB neurons in ****. Using in vivo fiber photometry, we found that the population activities of MPB neurons were inhibited during sevoflurane-induced loss of consciousness. Using in vitro whole-cell patch-clamp recordings, we revealed that sevoflurane suppressed the firing rate of MPB neurons in concentration-dependent and reversible manners. At a concentration equal to ****of hypnosis, sevoflurane potentiated synaptic GABAA receptors (GABAA-Rs), and the inhibitory effect of sevoflurane on the firing rate of MPB neurons was completely abolished by picrotoxin, which is a selective GABAA-R antagonist. At a concentration equivalent to ****of immobility, sevoflurane directly hyperpolarized MPB neurons and induced a significant decrease in membrane input resistance by increasing a basal potassium conductance. Moreover, pharmacological blockade of GABAA-Rs in the MPB prolongs induction and shortens emergence under sevoflurane inhalation at ****of hypnosis. These results indicate that sevoflurane inhibits MPB neurons through postsynaptic GABAA-Rs and background potassium channels, which contributes to sevoflurane-induced hypnosis.The NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome has been implicated as a crucial component in both neurodegeneration and diabetes. However, the role of metabolic signalling pathways and the NLRP3 inflammasome in frontotemporal dementia remain largely elusive. We therefore investigated the effects of an NLRP3 inhibitor (MCC950) in a murine tau knock-in (PLB2TAU) model vs. wild-type (PLBWT) control ****. In male PLB2TAU **** (4 months at start of study), MCC950 treatment (20 mg/kg, for 12 weeks) improved insulin sensitivity and reduced circulating plasma insulin levels. Further molecular analysis suggested normalisation in insulin signalling pathways in both liver and muscle tissue. Treatment also resulted in improvements in inflammation and ER stress signalling, both peripherally and centrally, alongside a partial normalisation of phospho-tau levels. Overall, we provide evidence that MCC950 improved metabolic, inflammatory and frontotemporal dementia (FTD) relevant phenotypes in multiple tissues. NLRP3 inhibition may therefore offer a therapeutic approach to ameliorate FTD pathology.Intracellular signalling pathways have been extensively studied as therapeutic targets for the treatment of mental diseases. Our attention has been caught by two kinases potentially involved in anxiety, ERK1/2 and CaMKII. The study aimed to examine changes in the activation of ERK1/2 and CaMKII concerning anxiolytic-like behaviours in ****. To evaluate anxiety-related response in ****, we used the open field test and the elevated plus maze test. Behavioural studies were complemented with the immunoblotting analysis to identify proteins of interest in the cortex, hippocampus, and striatum. We analysed the phosphorylation status of ERK1/2 and CaMKII in **** treated with a well-known anxiolytic drug - diazepam. Next, the blockade of ERK1/2 pathway by SL-327, a selective MEK1/2 inhibitor, was checked for anxiolytic action. Finally, the co-administration of subeffective doses of diazepam and SL-327 was investigated for a potential synergistic anxiolytic effect. Anxiolytic effects of acute diazepam are accompanied by decreased p-ERK1/2 and upregulation of p-CaMKII. Subchronic treatment with SL-327 leads to the manifestation of anxiolytic-like behaviours and changes in the phosphorylation status of both kinases in a diazepam-like manner. Co-administration of subeffective doses of SL-327 and diazepam induces anxiolysis, which is CaMKII-independent and correlates to selectively decreased phosphoactive ERK1/2 in the hippocampus. The MEK-ERK pathway is significantly involved in anxiolytic action of diazepam and its prolonged inhibition produces anxiolytic-like phenotype in ****. ERK inhibition could be used to manage anxiety symptoms in a benzodiazepine-sparing regimen for treatment of anxiety.Amyloid-β (Aβ) accumulation is a pathological hallmark of Alzheimer's disease (AD). The receptor for advanced glycation end products (RAGE) is involved in the production and accumulation of Aβ. RP1, a peptide antagonist of RAGE, was screened by phage display technology in our previous studies, and its neuroprotective effects on an AD cell model have been confirmed. However, its efficacy in vivo remains unclear. Here, the intranasal delivery of RP1 to APPSwe/PS1dE9 (APP/PS1) **** significantly improved memory impairment and relieved the Aβ burden by decreasing the expression of amyloid precursor protein and β-secretase. RNA-sequencing (RNA-seq) was utilized to identify differentially expressed genes (DEGs) in APP/PS1 **** after RP1 administration. Several DEGs in RAGE downstream signalling pathways were downregulated. Some transcription factors (such as Fos) and the pathways enriched in the remarkable modules may also be related to the efficacy of RP1. In conclusion, RP1 significantly improves the AD symptoms of APP/PS1 ****, and the RNA-seq results provide new ideas for elucidating the possible mechanisms of RP1 treatment.
NIR, a novel INHAT, negatively regulates the transcription activity of tumor repressor p53. However, if NIR functions in the tumorigenesis dependent on the regulation of p53 remains unknown. Here, we report that NIR promotes progression of colorectal cancer (CRC) through regulating RB function. Firstly, we found that NIR expression is upregulated in the human CRC tissues and significantly associated with the poor outcome of the patients. Sequence alignment shows that NIR contains an RB-binding motif LxCxE in its INHAT-2 domain. We demonstrate that NIR interacts with RB via INHAT-2 in CRC cells and promotes RB degradation through proteasome-mediated pathway. Further, either full-length GFP-NIR or GFP-NIR-INHAT2 facilitates poly-ubiquitination of RB. In addition, NIR inhibits RB acetylation by INHAT-2, suggesting NIR might promote RB degradation through inhibiting RB acetylation. Importantly, endogenous NIR is downregulated upon DNA damage, which is consistent with the upregulation of total level and acetylation of RB. We further show that Flag-NIR inhibits DNA damage-induced RB acetylation. https://www.selleckchem.com/products/i-bet-762.html Thus, downregulation of NIR might contribute to maintain the cellular homeostasis under DNA damage. Consequently, depletion of NIR inhibits cell proliferation and tumor growth in mouse xenografts. Taken together, we demonstrate that NIR promotes CRC progression partially through inhibiting RB acetylation and promoting RB degradation. Targeting NIR may provide a potential therapeutic strategy for NIR-upregulated CRC patients.Despite persistent clinical use for over 170 years, the neuronal mechanisms by which general anesthetics produce hypnosis remain unclear. Previous studies suggest that anesthetics exert hypnotic effects by acting on endogenous arousal circuits. Recently, it has been shown that the medial parabrachial nucleus (MPB) is a novel wake-promoting component in the dorsolateral pons. However, it is not known whether and how the MPB contributes to anesthetic-induced hypnosis. Here, we investigated the action of sevoflurane, a widely used volatile anesthetic agent that best represents the drug class of halogenated ethers, on MPB neurons in mice. Using in vivo fiber photometry, we found that the population activities of MPB neurons were inhibited during sevoflurane-induced loss of consciousness. Using in vitro whole-cell patch-clamp recordings, we revealed that sevoflurane suppressed the firing rate of MPB neurons in concentration-dependent and reversible manners. At a concentration equal to MAC of hypnosis, sevoflurane potentiated synaptic GABAA receptors (GABAA-Rs), and the inhibitory effect of sevoflurane on the firing rate of MPB neurons was completely abolished by picrotoxin, which is a selective GABAA-R antagonist. At a concentration equivalent to MAC of immobility, sevoflurane directly hyperpolarized MPB neurons and induced a significant decrease in membrane input resistance by increasing a basal potassium conductance. Moreover, pharmacological blockade of GABAA-Rs in the MPB prolongs induction and shortens emergence under sevoflurane inhalation at MAC of hypnosis. These results indicate that sevoflurane inhibits MPB neurons through postsynaptic GABAA-Rs and background potassium channels, which contributes to sevoflurane-induced hypnosis.The NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome has been implicated as a crucial component in both neurodegeneration and diabetes. However, the role of metabolic signalling pathways and the NLRP3 inflammasome in frontotemporal dementia remain largely elusive. We therefore investigated the effects of an NLRP3 inhibitor (MCC950) in a murine tau knock-in (PLB2TAU) model vs. wild-type (PLBWT) control mice. In male PLB2TAU mice (4 months at start of study), MCC950 treatment (20 mg/kg, for 12 weeks) improved insulin sensitivity and reduced circulating plasma insulin levels. Further molecular analysis suggested normalisation in insulin signalling pathways in both liver and muscle tissue. Treatment also resulted in improvements in inflammation and ER stress signalling, both peripherally and centrally, alongside a partial normalisation of phospho-tau levels. Overall, we provide evidence that MCC950 improved metabolic, inflammatory and frontotemporal dementia (FTD) relevant phenotypes in multiple tissues. NLRP3 inhibition may therefore offer a therapeutic approach to ameliorate FTD pathology.Intracellular signalling pathways have been extensively studied as therapeutic targets for the treatment of mental diseases. Our attention has been caught by two kinases potentially involved in anxiety, ERK1/2 and CaMKII. The study aimed to examine changes in the activation of ERK1/2 and CaMKII concerning anxiolytic-like behaviours in mice. To evaluate anxiety-related response in mice, we used the open field test and the elevated plus maze test. Behavioural studies were complemented with the immunoblotting analysis to identify proteins of interest in the cortex, hippocampus, and striatum. We analysed the phosphorylation status of ERK1/2 and CaMKII in mice treated with a well-known anxiolytic drug - diazepam. Next, the blockade of ERK1/2 pathway by SL-327, a selective MEK1/2 inhibitor, was checked for anxiolytic action. Finally, the co-administration of subeffective doses of diazepam and SL-327 was investigated for a potential synergistic anxiolytic effect. Anxiolytic effects of acute diazepam are accompanied by decreased p-ERK1/2 and upregulation of p-CaMKII. Subchronic treatment with SL-327 leads to the manifestation of anxiolytic-like behaviours and changes in the phosphorylation status of both kinases in a diazepam-like manner. Co-administration of subeffective doses of SL-327 and diazepam induces anxiolysis, which is CaMKII-independent and correlates to selectively decreased phosphoactive ERK1/2 in the hippocampus. The MEK-ERK pathway is significantly involved in anxiolytic action of diazepam and its prolonged inhibition produces anxiolytic-like phenotype in mice. ERK inhibition could be used to manage anxiety symptoms in a benzodiazepine-sparing regimen for treatment of anxiety.Amyloid-β (Aβ) accumulation is a pathological hallmark of Alzheimer's disease (AD). The receptor for advanced glycation end products (RAGE) is involved in the production and accumulation of Aβ. RP1, a peptide antagonist of RAGE, was screened by phage display technology in our previous studies, and its neuroprotective effects on an AD cell model have been confirmed. However, its efficacy in vivo remains unclear. Here, the intranasal delivery of RP1 to APPSwe/PS1dE9 (APP/PS1) mice significantly improved memory impairment and relieved the Aβ burden by decreasing the expression of amyloid precursor protein and β-secretase. RNA-sequencing (RNA-seq) was utilized to identify differentially expressed genes (DEGs) in APP/PS1 mice after RP1 administration. Several DEGs in RAGE downstream signalling pathways were downregulated. Some transcription factors (such as Fos) and the pathways enriched in the remarkable modules may also be related to the efficacy of RP1. In conclusion, RP1 significantly improves the AD symptoms of APP/PS1 mice, and the RNA-seq results provide new ideas for elucidating the possible mechanisms of RP1 treatment.
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