Lung injury caused by paraquat poisoning results in increased interleukin-6 and decreased microRNA-146a levels

Concentration of Serum Biomarkers of Brain Injury in Neonates With a Low Cord pH With or Without Mild Hypoxic-Ischemic Encephalopathy

Objective

To determine the concentrations of four neuroprotein biomarkers and 68 miRNAs in neonates with low cord pH and/or mild hypoxic-ischemic encephalopathy (HIE).

Study Design

A prospective cohort study enrolled neonates with low cord pH (n = 18), moderate-severe HIE (n = 40), and healthy controls (n = 38). Groups provided serum samples at 0–6 h of life. The concentrations of biomarkers and miRNAs were compared between cohorts.

Result

The low cord pH and moderate-severe HIE groups had increased concentrations of GFAP, NFL and Tau compared to controls (P < 0.05, P < 0.001, respectively). NFL concentrations in mild HIE was higher than controls (P < 0.05) but less than moderate-severe HIE (P < 0.001). Of 68 miRNAs, 36 in low cord pH group and 40 in moderate-severe HIE were upregulated compared to controls (P < 0.05). Five miRNAs in low cord pH group (P < 0.05) and 3 in moderate-severe HIE were downregulated compared to controls (P < 0.05).

Conclusion

A biomarker panel in neonates with low cord pH may help clinicians make real-time decisions.

Cytokine changes in fatal cases of paraquat poisoning

Cytokine-mediated inflammation is involved in the pathophysiology of paraquat toxicity. Nevertheless, few human studies have examined fluctuations in circulating cytokine levels. Blood samples were obtained from 21 patients with paraquat poisoning and compared to those of 18 healthy controls. All paraquat patients received a standard detoxification protocol composed of hemoperfusion, pulse therapies of methylprednisolone and cyclophosphamide, followed by dexamethasone therapy. Nonsurvivors not only had higher scores for the severity index of paraquat poisoning (P=0.004) but also presented with higher white blood cell counts (P=0.046) than survivors. Multiplex immunoassays revealed higher circulating levels of interleukin 2 (IL-2), interleukin 9 (IL-9), interleukin 10 (IL-10) and macrophage inflammatory protein-1 beta (MIP-1β) in survivors than in healthy controls. Furthermore, the circulating levels of interleukin 1 beta (IL-1β), IL-2, interleukin 5 (IL-5), interleukin 8 (IL-8), IL-9, IL-10, interleukin 12 (IL-12 p70), interleukin 17A (IL-17A), eotaxin, granulocyte colony-stimulating factor (G-CSF), monocyte chemoattractant protein-1 (MCP-1), interferon gamma-induced protein 10 (IP-10) and MIP-1β were higher in nonsurvivors than in healthy controls. Finally, the circulating levels of IL-1β and MCP-1 were higher in nonsurvivors than in survivors. Therefore, the observation of cytokine-mediated inflammation is in line with the detoxification protocol because glucocorticoids and cyclophosphamide are potent anti-inflammatory agents. Additionally, circulating levels of IL-1β and MCP-1 could serve as promising prognostic markers for patients with paraquat poisoning.

Aberrant miR-219-5p is correlated with TLR4 and serves as a novel biomarker in patients with multiple organ dysfunction syndrome caused by acute paraquat poisoning

This study aimed to investigate the clinical significance of serum microRNA-219-5p (miR-219-5p) in patients with multiple organ dysfunction syndrome (MODS) caused by acute paraquat (PQ) poisoning, and its correlation with Toll-like Receptor 4 (TLR4). Luciferase reporter assay was used to investigate in vitro the correlation of miR-219-5p with TLR4. Serum miR-219-5p levels were evaluated by quantitative real-time polymerase chain reaction. Serum levels of TLR4, IL-1β, and TNF-α were measured by Enzyme-linked immune sorbent assay (ELISA). ROC analysis was performed to assess the diagnostic significance, Kaplan-Meier survival curves and Cox regression analysis were used to evaluate the prognostic value of miR-219-5p in MODS patients. TLR4 was a target gene of miR-219-5p and was increased in MODS patients. Serum miR-219-5p level was decreased and negatively correlated with TLR4 level in MODS patients (r = −0.660, P < 0.001), which had important diagnostic value and negatively correlated with APACHE II score in MODS patients. The miR-219-5p expression was markedly associated with the WBC, ALT, AST, PaCO₂, Lac, and APACHE II score. Non-survivals had more patients with low miR-219-5p expression. Patients with low miR-219-5p expression had shorter survival time. MiR-219-5p and APACHE II score were two independently prognostic factors for 28-day survival. MiR-219-5p was negatively correlated with, while TLR4 was positively correlated with the levels of IL-1β and TNF-α. The serum miR-219-5p level may be a potential biomarker for acute PQ-induced MODS diagnosis and prognosis. Furthermore, miR-219-5p may be associated with the progression of MODS by regulating TLR4-related inflammatory response.

Protective Effect of Trans-chalcone Against High-Fat Diet-Induced Pulmonary Inflammation Is Associated with Changes in miR-146a And pro-Inflammatory Cytokines Expression in Male Rats

High-fat diet (HFD) increases the risk of non-communicable inflammatory diseases including pulmonary disorders. Trans-chalcone is a chalcone with antioxidant and anti-inflammatory effects. This study aimed to explore the effect of this natural compound and molecular mechanism of its effect on HFD-induced pulmonary inflammation. Twenty-eight male Wistar rats were randomly divided into four main groups (n = 7 per each group): control, receiving 10% tween 80; Chal, receiving trans-chalcone, HFD, receiving a high-fat emulsion and 10% tween 80; HFD + Chal, receiving a high-fat emulsion and trans-chalcone. After 6 weeks, the lungs were dissected, and the expression levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and miR-146a were determined using real-time PCR. Moreover, histological analysis was done by hematoxylin and eosin staining. Significant elevations in TNF-α, IL-1β, IL-6, and miR-146a expression levels (P < 0.001) were observed within the lungs of HFD-fed rats compared with the control. However, oral administration of trans-chalcone reduced TNF-α, IL-1β, IL-6 (P < 0.001), and miR-146a (P < 0.05) expression levels and also improved HFD-induced histological abnormalities. These findings indicate that trans-chalcone ameliorates lung inflammatory response and structural alterations. It seems that this beneficial effect is associated with the down-regulation of pro-inflammatory cytokines and miR-146a.

Clinical significance of serum levels of microRNA-27a and its correlation with interleukin-10 in patients with multiple organ dysfunction syndrome caused by acute paraquat poisoning

The aims of the present study were to examine the clinical significance of serum microRNA-27a (miR-27a) levels in patients with multiple organ dysfunction syndrome (MODS) caused by acute paraquat poisoning and to investigate the correlation between miR-27a and interleukin (IL)-10. A total of 82 patients with MODS induced by acute paraquat poisoning and 88 healthy controls were recruited in the present study. Reverse transcription-quantitative PCR was used to measure serum miR-27a expression levels in patients with MODS and the control group. IL-10 serum levels were determined using ELISA. Decreased serum miR-27a level and increased IL-10 expression levels were detected in patients with paraquat poisoning compared with healthy controls (P<0.001). A moderately negative correlation was identified between the serum expression levels of miR-27a and IL-10 (r=-0.5225; P<0.001). miR-27a expression level was found to be associated with blood urea nitrogen, partial pressure of carbon dioxide, arterial blood lactic acid, and the acute physiology and chronic health evaluation II score (APACHE II; P<0.05). The area under the curve for miR-27a was 0.946, with a sensitivity of 86.6% and specificity of 87.5% at a cutoff value of 2.10. The non-survival patient group had lower miR-27a expression levels compared with the survival group (P<0.01). Multivariate Cox regression analyses suggested miR-27a expression level and APACHE II score were independent prognostic factors for 30-day mortality (P<0.01). The present results suggested that serum miR-27a level may be a potential novel diagnostic and prognostic factor for MODS caused by paraquat poisoning. Collectively, miR-27a may be involved in the process of MODS induced by paraquat poisoning by regulating the inflammatory response.

[Mechanism of ulinastatin in reducing lung inflammatory injury in rats with hemorrhagic shock]

OBJECTIVE

To investigate the effect of ulinastatin on the inflammatory mediators and their signaling pathways miR-146a/TLR4/NF-κB in rats with hemorrhagic shock.

METHODS

Seventy-two SD rats were randomly assigned into shock without resuscitation group (SR group, n=24), acetated Ringer's solution resuscitation group (AR group, n=24) and ulinastatin treatment group (n=24). In all the 3 groups hemorrhagic shock models were established by femoral artery bleeding (with the mean arterial pressure maintained at 30-40 mmHg) without resuscitation (in SR group) or with resuscitation (in AR and ulinastatin groups) using acetated Ringer's solution for 30 min at 60 min after the onset of shock. At 1, 4, and 6 h after the shock onset or immediately after shock if the rats died, the lung tissues were taken for measurement of mRNA expressions of miR-146a, tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), IL-4, IL-6 and IL-10 using real-time quantitative PCR and the protein expressions of TLR4, MyD88, IκB-α, p-IκB-α, NF-κB p65, IRAK4, p-IRAK4 (Thr345, Ser346), p-IRAK4 (Thr342) and TRAF6 using Western blotting. The lung histopathology of the rats was examined under optical microscope with HE staining.

RESULTS

Compared with the SR group, the rats in the AR group showed slightly alleviated inflammatory infiltration in the lung tissues with significantly increased mRNA levels of miR-146a, IL-4 and IL-10 (P < 0.05) and protein expressions of IκB-α, p-IRAK4 (Thr342) and p-IRAK4 (Thr345, ser346) (P < 0.05), and decreased mRNA levels of TNF-α, IL-1 and IL-6 (P < 0.05) and protein expressions of TLR4, MyD88, NF-κB p65, p-IκB-α, IRAK-4 and TRAF6 (P < 0.05). Compared with those in AR group, the rats in ulinastatin group showed further alleviation of inflammatory lung tissue injury, with increased mRNA levels of miR-146a, IL-4 and IL-10 (P < 0.01) and protein expressions of IκB-α, p-IRAK4 and p-IRAK4 (P < 0.01) and decreased mRNA levels of TNF-α, IL-1 and IL-6 (P < 0.01) and protein expressions of TLR4, MyD88, NF-κB p65, p-IκB-α, IRAK-4 and TRAF6 (P < 0.01).

CONCLUSIONS

Ulinastatin combined with acetated Ringer's solution resuscitation alleviates lung inflammations in rats with hemorrhagic shock possibly by enhancing miR-146a expression to regulate TLR4/NF-κB signaling pathway through a negative feedback mechanism and thus modulate the balance of pro-inflammatory and anti-inflammatory factors.

Multiple roles of microRNA-146a in immune responses and hepatocellular carcinoma

MicroRNAs (miRNAs/miRs), consisting of ~22 nucleotides of single-stranded RNA, participate in post-transcriptional gene regulation by binding to the 3′-untranslated region (UTR) of mRNAs, repressing their translation and promoting their degradation. Studies have shown that certain miRNAs play a key role in the control of various cellular activities, such as inhibiting inflammation, modulating cell differentiation and suppressing cancer growth. The role of miR-146a in the immune response and in the pathogenesis of hepatocellular carcinoma (HCC) has also been investigated. Although some studies have shown that increased miR-146a levels are associated with HCC, others have revealed that miR-146a suppresses cancer cell proliferation, invasion and metastasis. Toll-like receptor 4 (TLR4) signaling has an important role in regulating innate and adaptive immune responses. In addition, TLR4 is functionally expressed in HCC cells and promotes HCC cell proliferation, which can be regulated by miR-146a. The present review focuses on the recent progress in analyzing the multiple roles of miR-146a in mediating the TLR4 pathway and adaptive immune response. Finally, the function of miR-146a in the pathogenesis of HCC is also discussed.