Dexamethasone upregulates macrophage PIEZO1 via SGK1, suppressing inflammation and increasing ROS and apoptosis.

The side effects of high-dose dexamethasone in anti-infection include increased ROS production and immune cell apoptosis. Dexamethasone effectively activates serum/glucocorticoid-regulated kinase 1 (SGK1), which upregulates various ion channels by activating store-operated calcium entry (SOCE), leading to Ca2+ oscillations. PIEZO1 plays a crucial role in macrophages' immune activity and function, but whether dexamethasone can regulate PIEZO1 by enhancing SOCE via SGK1 activation remains unclear. The effects of dexamethasone were assessed in a mouse model of sepsis, and primary BMDMs and the RAW264.7 were treated with overexpression plasmids, siRNAs, or specific activators or inhibitors to examine the relationships between SGK1, SOCE, and PIEZO1. The functional and phenotypic changes of mouse and macrophage models were detected. The results indicate that high-dose dexamethasone upregulated SGK1 by activating the macrophage glucocorticoid receptor, which enhanced SOCE and subsequently activated PIEZO1. Activation of PIEZO1 resulted in Ca2+ influx and cytoskeletal remodelling. The increase in intracellular Ca2+ mediated by PIEZO1 further increased the activation of SGK1 and ORAI1/STIM1, leading to intracellular Ca2+ peaks. In the context of inflammation, activation of PIEZO1 suppressed the activation of TLR4/NFκB p65 in macrophages. In RAW264.7 cells, PIEZO1 continuous activation inhibited the change in mitochondrial membrane potential, accelerated ROS accumulation, and induced autophagic damage and cell apoptosis in the late stage. CaMK2α was identified as a downstream mediator of TLR4 and PIEZO1, facilitating high-dose dexamethasone-induced macrophage immunosuppression and apoptosis. PIEZO1 is a new glucocorticoid target to regulate macrophage function and activity. This study provides a theoretical basis for the rational use of dexamethasone.

LncRNA-mRNA Expression Profiles and Functional Networks Associated with Cognitive Impairment in Folate-deficient Mice.

BACKGROUND: Cognitive impairment is a common neurocognitive disorder that affects the health of millions of people worldwide, related to folate deficiency. OBJECTIVE: The present study aimed to investigate the lncRNA-mRNA functional networks associated with cognitive impairment in folate-deficient mice and elucidate their possible molecular mechanisms. METHODS: We downloaded the gene expression profile (GSE148126) of lncRNAs and mRNAs from NCBI Gene Expression Omnibus (GEO) database. Four groups of mouse hippocampi were analyzed, including 4 months (4mo) and 18 months (18mo) of folic acid (FA) deficiency/supplementation. The differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs) were identified using gplots and heatmap packages. The functions of the DEmRNAs were evaluated using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The hub genes were identified by CytoHubba plugins of Cytoscape, and protein-protein interaction (PPI) network of deregulated mRNAs was performed using the STRING database. Finally, lncRNA-mRNA co-expression and competitive endogenous RNA (ceRNA) network analyses were constructed. RESULTS: In total, we screened 67 lncRNAs with 211 mRNAs, and 89 lncRNAs with 229 mRNAs were differentially expressed in 4mo_FA and 18mo_FA deficient mice, respectively. GO analyses indicated that DEmRNAs were highly related to terms involved in binding and biological regulation. KEGG pathway analyses demonstrated that these genes were significantly enriched for renin secretion, pancreatic secretion, and AMPK signaling pathways in the 18mo_FA deficiency group. Subsequently, the top 5 hub genes were screened from the PPI network, which may be key genes with the progression of folate deficiency. Upon the lncRNA-mRNA co-expression network analysis, we identified the top 10 lncRNAs having the maximum number of connections with related mRNAs. Finally, a ceRNA network was constructed for DE lncRNAs and DEmRNAs, and several pivotal miRNAs were predicted. CONCLUSIONS: This study identified the lncRNA-mRNA expression profiles and functional networks associated with cognitive impairment in folate-deficient mice by bioinformatics analysis, which provided support for the possible mechanisms and therapy for this disease.

[Effect of triptolide on cognitive dysfunction in vascular dementia rats through SIRT1/NF-κB signaling pathway].

To investigate the effect of triptolide on cognitive dysfunction in vascular dementia rats and its effect on SIRT1/NF-κB pathway,fifty healthy male Sprague-Dawley rats were randomly divided into 5 groups: Sham operation group( Sham group),vascular dementia model group( 2 VO group),triptolide intraperitoneal injection group( TR group),triptolide intraperitoneal injection + EX527 intracerebroventricular administration group( T+E group),EX527 intracerebroventricular administration group( EX527 group). After 4 weeks of modeling,Morris water maze test and object recognition test were used to evaluate the learning and memory ability of rats. The morphological changes of hippocampus in each group were observed in brain tissue. The chemical colorimetry was used to detect the activities of SOD and MDA in hippocampus. IL-6 and TNF-α levels were detected by ELISA. Western blot was used to detect the expression of SIRT1,NF-κB,IκBα and caspase 3 in hippocampus. The results showed that compared with the Sham group,the learning and memory ability of the vascular dementia model rats was reduced,the SOD activity in the hippocampus was decreased,the MDA activity and IL-6 level were increased,the neuronal degeneration changed significantly,the expression of SIRT1 and IκBα was decreased and the expression of caspase 3 and NF-κB was significantly increased. After intervention by triptolide,the level of oxidative stress and the degenerative changes in hippocampus were significantly slowed down. The expression of SIRT1 and IκBα protein was increased and the expression of caspase 3 and NF-κB was significantly decreased. While,after intervention by triptolide and EX527,the expression of SIRT1 was decreased,the levels of oxidative stress and neuronal degeneration in the hippocampus were aggravated,and the learning and memory ability was reduced. The results showed that triptolide could improve cognitive impairment in vascular dementia rats and its mechanism may be related to SIRT1/NF-κB signaling pathway.

Protective and therapeutic effects of Danhong injection on acute pancreatitis­associated lung injury.

Lung functional impairment caused by acute pancreatitis (AP) is the primary contributor to AP­associated mortality. Previous studies have reported that AP­associated lung injury is associated with systemic inflammatory response syndrome and oxidative stress. In the present study, the protective effects of Danhong injection (DHI), a widely used Chinese Traditional Medicine preparation, on AP­associated lung injury in rats was examined. The myeloperoxidase activity, malondiadelhyde level and superoxide dismutase activity determination demonstrated the anti­inflammatory and anti­oxidative properties of DHI. The results of western blotting and reverse­transcription­semi­quantitative polymerase chain reaction indicated that DHI could protect rats against AP­associated lung injury, and the protective effect was associated with the suppression of nuclear factor­κB activation and cell adhesion molecule expression, and the reduction of neutrophil infiltration and oxidative stress levels. As demonstrated by HE staining, DHI inhibited the pancreas and lung tissue injury. Therefore, DHI could be a potential candidate for the treatment of patients with AP­associated lung injury.

[Effect of electroacupuncture for immune function of patients treated with laparoscopic radical rectectomy for rectal cancer].

OBJECTIVE: To observe the effect of electroacupuncture (EA) combined with general anesthesia for the immune function of patients treated with laparoscopic radical rectectomy for rectal cancer. METHODS: Fifty patients who would receive selective laparoscopic radical rectectomy for rectal cancer with general anesthesia were randomly divided into an observation group and a control group,25 cases in each one. Fifteen minutes before anesthesia induction,patients in the observation group were treated with EA at Zusanli (ST 36) and Sanyinjiao (SP 6) until the end of operation. Sham acupuncture without piercing the skin was applied at the same acupoints in the control group, and electrodes were connected without stimulation. Interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-6 (IL-6) were quantitatively tested before anesthesia (T0), at the time of abdomen closing (T1) and one hour after anesthesia anabiosis (T2). And serum procalcitonin (PCT) level, leucocyte count and the number of cases with increasing leucocyte (the standard number>10×109/L) were measured on the first day after operation. RESULTS: The levels of IL-4 and IL-6 were increased apparently and the ratio of IFN-γ/IL-4 was decreased at T2 compared with those before treatment in the control group (all P<0.05), but obvious change did not appear in the observation group (all P>0.05). The ratio of IFN-γ/IL-4 was enhanced (P<0.05),and the levels of IL-4 and IL-6 were reduced (both P<0.05) at T2 in the observation group compared with those in the control group. The level of PCT of the observation group was markedly lower than that of the control group on the first day after operation (P<0.05). There was no statistical significance about leucocyte count and the number of cases with increasing leucocyte between the two groups (both P>0.05). CONCLUSIONS: EA at Zusanli (ST 36) and Sanyinjiao (SP 6) could alleviate the depressing immune function and inflammatory reaction of patients after laparoscopic radical rectectomy for rectal cancer.