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RationaleNlrx1, a pattern recognition receptor belonging to the NLR family, is highly expressed in the heart and is significantly increased after myocardial infarction in vivo, however, the role of Nlrx1 in post-infarction inflammation and healing is poorly understood. Although the effects of infiltrating macrophages on survival of cardiomyocytes and healing of injured hearts have been intensely studied, whether or not and how surviving cardiomyocytes might influence the phenotype and function of macrophages in the infarcted hearts was largely unexplored.ObjectiveTo investigate the role of Nlrx1 in post-infarction inflammation and healing and to dissect the underlying mechanism.Methods and resultsSingle cell RNA-sequencing of 23,805 cells isolated from infarcted hearts revealed 7 clusters of infarct macrophages including CCR2+, Isg+, Mki67+proliferative, and LYVE1+cardiac resident macrophages, and identified a novel subset of CD9+Il1rn+macrophages, which were characterized by high expression ofCd9, Il1rn, GpnmbandSpp1,and downregulation of proinflammatory cytokines and chemokines. CD9+Il1rn+macrophages were largely found in infarcted hearts of Nlrx1KO mice, and were transcriptionally unique with reparative phenotype. Loss of Nlrx1 attenuated ventricular dysfunction and adverse remodeling, and decreased post-infarction mortality. Flow cytometry analysis showed markedly increased number of CD9+macrophages and higher mean fluorescence intensity of CD9 in Nlrx1KO mice. RNA-seq analysis revealed that CD9+macrophages of Nlrx1KO infarcted hearts exhibited a reparative and anti-inflammatory phenotype as featured by upregulation of wound healing-associated genes includingCD9, Spp1andFn1, and downregulation of proinflammatory genes. Conditioned medium from Nlrx1 deficient cardiomyocytes upon hypoxia stimulation skewed macrophage polarization towards a reparative and inflammation-suppressed phenotype. Gain-and loss-of function of Nlrx1 combined with RNA-seq analysis identified CCN2, whose expression and secretion were significantly increased in Nlrx1 deficient cardiomyocytes upon hypoxia, as a cardiomyocytes-derived mediator responsible, at least partly, for reprograming macrophage towards a reparative phenotype. In vivo, CCN2 expression was markedly elevated in Nlrx1KO infarcted hearts. Moreover, exogenous CCN2 partially mediated macrophage transition towards a reparative phenotype.ConclusionsCD9+IL1rn+macrophages modulated by Nlrx1 deficient cardiomyocytes-derived CCN2, is a novel subset of reparative macrophages contributing to infarct healing. Inhibition of myocardial Nlrx1 and/or activation of CCN2 to boost CD9+IL1rn+reparative macrophages may represent new therapeutics for infarct healing following ischemic injury.

The benefits and harms of corticosteroids for patients with severe coronavirus disease 2019 (COVID-19) remain unclear. We systematically searched PubMed, Embase, and Cochrane Central Register of Controlled Trials from December 31, 2019 to October 1, 2020 to identify randomized controlled trials (RCTs) that evaluated corticosteroids in severe COVID-19 patients. The primary outcome was all-cause mortality at the longest follow-up. Secondary outcomes included a composite disease progression (progression to intubation, ventilation, extracorporeal membrane oxygenation, ICU transfer, or death among those not ventilated at enrollment) and incidence of serious adverse events. A random-effects model was applied to calculate risk ratio (RR) with 95% confidence intervals (CIs). We used the Grading of Recommendations Assessment, Development, and Evaluation approach to evaluate the certainty of the evidence. Seven RCTs involving 6250 patients were included, of which the Randomized Evaluation of COVID-19 Therapy (RECOVERY) trial comprised nearly 78% of all included subjects. Results showed that corticosteroids were associated with a decreased all-cause mortality (27.3 vs. 31.1%; RR: 0.85; 95% CI: 0.73–0.99; P = 0.04; low-certainty evidence). Trial sequential analysis suggested that more trials were still required to confirm the results. However, such survival benefit was absent if RECOVERY trial was excluded (RR: 0.83; 95% CI: 0.65–1.06; P = 0.13). Furthermore, corticosteroids decreased the occurrence of composite disease progression (30.6 vs. 33.3%; RR: 0.77; 95% CI: 0.64–0.92; P = 0.005), but not increased the incidence of serious adverse events (3.5 vs. 3.4%; RR: 1.16; 95% CI: 0.39–3.43; P = 0.79).

The present study aimed to compare the effects of oxycodone and morphine hydrochloride on the proliferation, apoptosis and migration of A549 lung cancer cells. A549 human lung cancer cells were cultured in vitro and treated with oxycodone or morphine at various concentrations (10, 20 and 40 µg/ml). Cell migration was determined using a wound healing assay, whereas apoptosis was detected using flow cytometry. Reverse transcription quantitative-polymerase chain reaction was performed in order to assess the apoptosis-related gene expression levels, including p53, B-cell lymphoma (Bcl)-2 and Bcl-2-associated X protein (Bax). The levels of vascular endothelial growth factor (VEGF) and urokinase-type plasminogen activator (uPA) were detected using enzyme-linked immunosorbent assays. The expression levels of intercellular cell adhesion molecule (ICAM)-1 were determined by immunofluorescence. In the present study, oxycodone and morphine induced apoptosis in A549 lung cancer cells with similar potency; however, >20 µg/ml oxycodone was more effective at inhibiting cell proliferation (P

Oxidative stress causes mitochondrial impairment, the failure of energy production, and consequent organ dysfunctions. The aim of the present study was to investigate the potential therapeutic effects of mitochondrial antioxidant SS-31 on sepsis-induced organ dysfunctions and to explore the possible mechanism. Sepsis was induced by cecal ligation and puncture. Immediately and at 5 h after the operation, SS-31 (5 mg/kg) or vehicle was administered intraperitoneally. The levels of organ dysfunctions, malondialdehyde, superoxide dismutase, proinflammatory cytokines, pulmonary wet-to-dry weight ratio, myeloperoxidase activity, histological scores, nuclear factor kappa B p65, inducible nitric oxide synthase, reactive oxygen species, adenosine triphosphate, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells were assessed at the indicated time points. The 7-day survival rate was estimated by the Kaplan-Meier method. In the present study, SS-31 treatment significantly improved sepsis-induced organ dysfunctions as evidenced by decreased histological scores, increased arterial partial oxygen tension, and deceased serum alanine aminotransferase, urea nitrogen, and creatinine levels, which was accompanied by decreased levels of malondialdehyde, tumor necrosis factor-alpha, pulmonary myeloperoxidase activity, nuclear factor kappa B p65, inducible nitric oxide synthase, reactive oxygen species, and TUNEL-positive cells. In conclusion, our data suggested that the protective effects of SS-31 on sepsis-induced organ dysfunctions were associated with the inhibition of proinflammatory cytokines, oxidative stress, and apoptosis.

Sepsis-associated encephalopathy (SAE) is a common complication after sepsis development, which is associated with the poor prognosis. However, no effective agent is currently available to treat this complication. The objective of the present study was to investigate whether low-molecular-weight heparin (LMWH) has protective effects against sepsis-induced cognitive impairments. Male mice were randomly divided into the control + vehicle, control + LMWH, lipopolysaccharide (LPS) + vehicle, or LPS + LMWH group. LMWH was administrated 30 min after the LPS administration (5 mg/kg) and daily afterward for 2 days. The survival rate was estimated by the Kaplan-Meier method. Behavioral tests were performed by open field and fear conditioning tests at day 7 after LPS administration. The levels of tumor necrosis factor alpha, interleukin (IL)-1β, IL-6, IL-10, malondialdehyde, and superoxide dismutase, Toll-like receptor 4, nuclear factor kappa B p65, inducible nitric oxide synthase, cyclooxygenase-2, occluding, high mobility group box-1, brain derived neurotrophic factor, and IBA1 positive cells were assessed at the indicated time points. LMWH attenuated LPS-induced hippocampus-dependent cognitive impairments, which was accompanied by decreased hippocampal IL-1β, malondialdehyde, Toll-like receptor 4, nuclear factor kappa B p65, inducible nitric oxide synthase, cyclooxygenase-2, high mobility group box-1 protein, and IBA1 positive cells, and increased occluding and brain derived neurotrophic factor levels. In conclusion, LMWH treatment protects against sepsis-induced cognitive impairments by attenuating hippocampal microglial activation, cytokine and oxidative stress production, disruption of blood-brain barrier, and the loss of synaptic plasticity related proteins.

This study aims to determine whether levosimendan combined with arginine vasopressin infusion supplemented with norepinephrine can improve hemodynamics and pulmonary dysfunction. The study was tested in a fecal peritonitis-induced septic shock model, we observed that levosimendan combined with arginine vasopressin supplemented with norepinephrine therapy resulted in lower mean pulmonary artery pressure, lactate concentrations, arterial total nitrate/nitrite, and high-mobility group box 1 levels; decreased lung wet/dry ratio, and pulmonary levels of interleukin-6, total histological scores, and improved pulmonary gas exchange when compared with norepinephrine group. Levosimendan combined with arginine vasopressin supplemented with norepinephrine infusion shows potential benefit in sepsis-induced acute lung injury by decreasing mean pulmonary artery pressure and attenuating inflammatory responses in the lung compared to norepinephrine infusion alone.