Mesencephalic astrocyte-derived neurotrophic factor attenuates acute lung injury via inhibiting macrophages' activation

Acute lung injury (ALI) is an urgent respiratory disease without effective treatment. Mesencephalic astrocyte-derived neurotrophic factor (MANF)has been demonstrated to play a suppressive role in some inflammatory conditions. However, the effect of MANF on ALI has not yet been reported. In this study, we collected bronchoalveolar lavage fluid (BALF) from the patients with or without pulmonary inflammation, and used lipopolysaccharide (LPS) to induce mice ALI model. Mono-macrophage-specific MANF knockout (MKO) mice were constructed and recombinant human MANF protein was used to ALI mice. We found that the endogenous MANF protein in both human BALF and mice lung tissues was increased in inflammatory conditions. MANF level in the macrophages of inflammatory lung was higher than that in normal controls in both human and mice. MANF deficiency in macrophages induced lung inflammation and aggravated LPS-induced lung injury. MANF lowered LPS-induced lung injury, inhibited macrophage polarization to M1 functional type. Meanwhile, MANF inhibited-LPS induced activation of NF-κB signal pathway by down regulating phosphorylated p65in lung tissue and macrophages. These results indicate that MANF acts as a suppressor in ALI via negatively regulating NF-κB activation and macrophages polarization, which may be a novel potential target and shed light on ALI therapy.

Zonisamide, an antiepileptic drug, alleviates diabetic cardiomyopathy by inhibiting endoplasmic reticulum stress

Endoplasmic reticulum stress (ER stress) plays a key role in the development of cardiac hypertrophy and diabetic cardiomyopathy (DCM). Zonisamide (ZNS) was originally developed as an antiepileptic drug. Studies have shown that ZNS suppresses ER stress-induced neuronal cell damage in the experimental models of Parkinson's disease. Herein, we investigated whether ZNS improved DCM by attenuating ER stress-induced apoptosis. C57BL/6J mice were fed with high-fat diet (HFD) and intraperitoneally injected with low-dose streptozotocin (STZ) to induce type 2 diabetes mellitus (T2DM), and then treated with ZNS (40 mg·kg-1·d-1, i.g.) for 16 weeks. We showed that ZNS administration slightly ameliorated the blood glucose levels, but significantly alleviated diabetes-induced cardiac dysfunction and hypertrophy. Furthermore, ZNS administration significantly inhibited the Bax and caspase-3 activity, upregulated Bcl-2 activity, and decreased the proportion of TUNEL-positive cells in heart tissues. We analyzed the hallmarks of ER stress in heart tissues, and revealed that ZNS administration significantly decreased the protein levels of GRP78, XBP-1s, ATF6, PERK, ATF4, and CHOP, and elevated Hrd1 protein. In high glucose (HG)-treated primary cardiomyocytes, application of ZNS (3 μM) significantly alleviated HG-induced cardiomyocyte hypertrophy and apoptosis. ZNS application also suppressed activated ER stress in HG-treated cardiomyocytes. Moreover, preapplication of the specific ER stress inducer tunicamycin (10 ng/mL) eliminated the protective effects of ZNS against HG-induced cardiac hypertrophy and ER stress-mediated apoptosis. Our findings suggest that ZNS improves the cardiac diastolic function in diabetic mice and prevents T2DM-induced cardiac hypertrophy by attenuating ER stress-mediated apoptosis.

Zonisamide Ameliorates Cognitive Impairment by Inhibiting ER Stress in a Mouse Model of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) increases the risk of Alzheimer’s disease (AD)-like dementia and pathology. Endoplasmic reticulum stress (ERS) plays a key role in the development of cognitive impairment in T2DM. Zonisamide (ZNS) was found to suppress ERS-induced neuronal cell damage in the experimental models of Parkinson’s disease (PD). However, the protective effect of Zonisamide in the treatment of diabetes-related dementia is not determined. Here, we studied whether ZNS can attenuate cognitive impairments in T2DM mice. C57BL/6J mice were fed with a high-fat diet (HFD) and received one intraperitoneal injection of streptozotocin (STZ) to develop T2DM. After the 9-week diet, the mice were orally gavaged with ZNS or vehicle for 16 consecutive weeks. We found that ZNS improved spatial learning and memory ability and slightly attenuated hyperglycemia. In addition, the expression levels of synaptic-related proteins, such as postsynaptic density 95 (PSD95) and synaptophysin, were increased along with the activation of the cyclic AMP response element-binding (CREB) protein and cAMP-dependent protein kinase (PKA) both in the hippocampus and cortex of T2DM mice. Meanwhile, ZNS attenuated Aβ deposition, Tau hyperphosphorylation at Ser-396/404, and also decreased the activity of Tau upstream kinases including extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK). Moreover, ZNS also decreased the ERS hallmark protein levels. These data suggest that ZNS can efficiently prevent cognitive impairment and improve AD-like pathologies by attenuating ERS in T2DM mice.

Comparison of Sevoflurane and Propofol on the Incidence of Postoperative Pain and Quality of Life in Patients Undergoing Total Knee Arthroplasty With Chronic Pain Before Surgery

BACKGROUND

Propofol and sevoflurane as frequently used general anesthetics can affect postoperative pain. Our study explored whether the incidence of postoperative pain differed among patients with chronic pain undergoing total knee arthroplasty (TKA) anesthetized with sevoflurane or propofol.

METHODS

Patients were randomly assigned to groups receiving either sevoflurane (Group S, n = 50) or propofol (Group P, n = 47) for anesthesia maintenance during TKA. The incidences of postoperative pain and quality of life (QoL) were measured using the EuroQol 5-Dimension (EQ-5D) scale at 1, 3, and 7 days post-operation (DPO), and 1 and 3 months post-operation (MPO).

RESULTS

At 3 DPO, fewer patients reported moderate pain (P = 0.001) and more patients reported no pain (P = 0.003) in Group S than that in Group P. At 3 MPO, more patients reported no pain (P = 0.04) and fewer patients reported moderate pain (P = 0.04) in Group S than in Group P. No significant differences were found in the incidence of postoperative pain between the 2 groups of patients at the other time points. The EQ-5D scores were higher in Group S than in Group P (P = 0.022), and the difference was 0.15 at most, which was not optimal. The EQ-5D clinical results might be not very significant.

CONCLUSIONS

Sevoflurane anesthesia may have potential advantages in reducing postoperative pain in patients undergoing TKA with a preoperative VAS score > 4.

Sialic acid-modified chitosan oligosaccharide-based biphasic calcium phosphate promote synergetic bone formation in rheumatoid arthritis therapy

Therapeutic goals for rheumatoid arthritis (RA) consist of inhibiting the inflammatory response and repairing the damaged bone/cartilage. Tissue engineering could achieve both goals, however, it was hindered due to the lack of biologically relevant tissue complexity, limitation in covering the entire polyarthritis lesions and requirement of extra surgical implantation. Integrating nanotechnologies into clinically sized implants represents a major opportunity to overcome these problems. Herein, we designed a sialic acid (SA)-modified chitosan oligosaccharide-based biphasic calcium phosphate (BCP), a biomimetic nanoplatform that could load with methotrexate. We found that SA modification could not only improve the accumulation of the designed organic-inorganic nanoplatform in arthritic paws (34.38% higher than those without SA modification at 48 h), but also cooperate with BCP to exert synergetic mineralization of calcium phosphate, allowing more osteoblasts to attach, proliferate and differentiate. The more differentiated osteoblasts produced 4.46-fold type I collagen and 2.60-fold osteoprotegerin compared to the control group. Besides, the disassembled nanorods released chitosan oligosaccharide-based micelles, revealing a cartilage-protective effect by reducing the loss of glycosaminoglycan. All these improvements contributed to the light inflammatory response and reduced destruction on cartilage/bone. The findings provide a novel strategy for RA therapy via nanometer-scale dimension mimicking the natural tissues.

JNK-TLR9 signal pathway mediates allergic airway inflammation through suppressing melatonin biosynthesis

Toll-like receptors (TLRs) play pivotal role in the pathogenesis of allergic airway diseases such as asthma. TLR9 is one of the most extensively studied TLRs as an approach to treat asthma. In this study, we investigated the role of TLR9 in the allergic airway inflammation and the underlying mechanism. Wild-type (WT) mice and TLR9(-/-) mice were sensitized and challenged with OVA to establish allergic airway disease model. We found that the expression of TLR9 was elevated concomitantly with airway inflammation post-OVA challenge, and TLR9 deficiency effectively inhibited airway inflammation, including serum OVA-specific immunoglobulin E (IgE), pulmonary inflammatory cell recruitment, mucus secretion, and bronchoalveolar lavage fluid (BALF) inflammatory cytokine production. Meanwhile, the protein expression of hydroxyindole-o-methyltransferase (HIOMT) in lung tissues, the level of melatonin in serum, and BALF were reduced in OVA-challenged WT mice, while these reductions were significantly restored by TLR9 deficiency. Additionally, we showed that although TLR9 deficiency had no effect on OVA-induced phosphorylation of JNK, inhibition of JNK by specific inhibitor SP600125 significantly decreased OVA-induced expression of TLR9, suggesting that JNK is the upstream signal molecular of TLR9. Furthermore, SP600125 treatment promoted resolution of allergic airway inflammation in OVA-challenged WT mice, but not further ameliorated allergic airway inflammation in OVA-challenged TLR9(-/-) mice. Similarly, SP600125 significantly restored the protein expression of HIOMT and the level of melatonin in OVA-challenged WT mice, while such effect was not further enhanced by TLR9 deficiency. Collectively, our results indicated that JNK-TLR9 signal pathway mediates allergic airway inflammation through suppressing melatonin biosynthesis.

[Effect of Toll-like receptor 2 on the inhibition role of sevoflurane on airway inflammation in asthmatic mice]

OBJECTIVE

To investigate the effect of Toll-like receptor 2 (TLR2) on the inhibition role of sevoflurane on airway inflammation in asthmatic mice.

METHODS

The lung tissue samples of C(57) BL/6 mice used in this study were from previous research, including control group, asthma group and sevoflurane group, 8 samples in each group. Twenty-four specific pathogen free female TLR2 gene deletion (TLR2(-/-)) mice were randomly assigned to control group, asthma group and sevoflurane group, with 8 mice in each group. Asthma group and sevoflurane group were then sensitized and challenged with ovalbumin (OVA) to establish asthma model, combined with repeated inhalation of 3% sevoflurane in sevoflurane group. In C(57) mice, expression levels of TLR2 were detected using Western blotting analyses. In TLR2(-/-) mice, numbers of differential inflammatory cells were investigated; levels of tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10) in bronchoalveolar lavage fluid (BALF) were measured by enzyme linked immunosorbent assay (ELISA); lung tissue inflammation was detected with HE staining.

RESULTS

In lung tissues from C(57) mice, levels of protein expression of TLR2 in asthma group (0.547±0.042) were higher than those in control group (0.312±0.023) (P=0.023) and sevoflurane group (0.287±0.033) (P=0.020). In TLR2(-/-) mice, the number of total cells ((83.13±19.43)×10(3)/ml), numbers of differential inflammatory cells and TNF-α level ((546±16) pg/ml) in BALF in sevoflurane group were lower than those in asthma group ((206.43±41.82)×10(3)/ml, (732±41) pg/ml), but still higher than those in control group ((44.64±7.17)×10(3)/ml, (380±24) pg/ml) (all P<0.05); lung tissue inflammation was inhibited in sevoflurane group than in asthma group, but still more obvious than that in control group.

CONCLUSION

Toll like receptor 2 involved in the anti-inflammatory effect of sevoflurane on asthmatic airway inflammation in mice.

Associations of pulmonary function with serum biomarkers and dialysis adequacy in patients undergoing peritoneal dialysis

BACKGROUND

As lung impairment is an indicator of increased morbidity and mortality in patients receiving continuous ambulatory peritoneal dialysis (CAPD), the risk factors associated with impaired lung function are of great significance. The aim of this study is to elucidate the effects of inflammatory biomarkers and dialysis adequacy on pulmonary function, in CAPD patients.

METHODS

101 patients undergoing CAPD, 30 CKD5 patients and 30 healthy subjects were enrolled. Spirometry and serum biomarkers were evaluated in each subject. Pulmonary function was compared among patients and control groups. Pearson analysis was used to analyze the correlation between serum biomarkers, dialysis adequacy and pulmonary function.

RESULTS

Lower vital capacity, maximal voluntary ventilation (MVV), forced vital capacity (FVC), peak expiratory flow (PEF), maximal mid-expiratory flow rate (MMEF), and diffusing capacity of the lung for carbon monoxide (DLCO) were observed in the CAPD group (all P < 0.05) when compared with control subjects. DLCO % was negatively correlated with CRP (r = -0.349, P = 0.007) and positively correlated with albumin (r = 0.401, P = 0.002). Total Kt/V was associated positively with MMEF % (r = 0.316, P = 0.019), and MVV % (r = 0.362, P = 0.007). nPNA was positively correlated with FVC % (r = 0.295, P = 0.049) and MMEF % (r = 0.381, P = 0.010).

CONCLUSION

The results suggest that lung function decline was directly related to higher CRP level, hypoalbuminemia, and dialysis inadequacy. These findings provide the evidence that inflammation and dialysis adequacy play a role in predicting outcomes of CAPD patients with pulmonary impairment.

Down-regulation of GRα expression and inhibition of its nuclear translocation by hypoxia

AIMS

Glucocorticoids are the most effective anti-inflammatory agent in treating pulmonary diseases typically accompanied by hypoxia. Our previous study has demonstrated that glucocorticoid receptor α (GRα) expression is reduced in hypoxia but the underlying mechanism remains elusive. In this study we aim to identify the signaling pathway involved in hypoxia-induced down-regulation of GRα, and whether hypoxia affects nuclear translocation of GRα.

MAIN METHODS

Female C57BL/6 mice were sensitized with saline or ovalbumin (OVA) as the in vivo model. Mice were divided into control and OVA groups, and their lung histology and the expression of hypoxia inducible factor (HIF-1) and GRα were examined. A549 cells were exposed to chemical hypoxia as the in vitro model, where mitogen-activated protein kinases (MAPKs) were inhibited specifically by SB203580. Next, under normal or hypoxic conditions, the expression of GRα, MAPKs and HIF-1 signal protein were determined by Western blot analysis, and GRα translocation were observed through live-cell imaging.

KEY FINDINGS

In OVA challenged mice the expression of GRα was down-regulated whereas HIF-1 was up-regulated. Hypoxia caused a time-dependent decrease of GRα expression, and activated multiple signaling pathways including MAPKs and HIF-1. Moreover, GRα expression increased with MAPK inhibition. Interestingly, only MAPK inhibitor SB203580, but not JNK inhibitor SP600125 or ERK inhibitor U0126 improved the expression of GRα under hypoxic condition. GRα nuclear translocation was also significantly inhibited by hypoxia.

SIGNIFICANCE

Hypoxia down-regulated the expression of GRα through p38 signaling pathway, as well as inhibited GRα nuclear translocation significantly.

SP600125 promotes resolution of allergic airway inflammation via TLR9 in an OVA-induced murine acute asthma model

BACKGROUND

c-Jun N-terminal kinase (JNK) relays extracellular stimuli through phosphorylation cascades that lead to various cell responses. In the present study, we aimed to investigate the effect of the JNK inhibitor SP600125 on the resolution of airway inflammation, and the underlying mechanism using a murine acute asthma model.

METHODS

Female C57BL/6 mice were sensitized with saline or ovalbumin (OVA) on day 0, and challenged with OVA on day 14-20. Meanwhile, some of the mice were treated with SP600125 (30 mg/kg) intraperitoneally 2 h before each challenge. The airway inflammation was evaluated by counting the numbers of various types of inflammatory cells in bronchoalveolar lavage fluid (BALF), histopathology, cytokines production and mucus secretion in individual mouse. In addition, we analyzed the protein levels of phosphorylated JNK and TLR9 in the lung tissues.

RESULTS

SP600125 markedly reduced the invasion of inflammatory cells into the peribronchial regions, and decreased the numbers of eosinophils, monocytes, neutrophils and lymphocytes in BALF. SP600125 also reduced the level of plasma OVA-specific IgE, lowered the production of pro-inflammatory cytokines in BALF and alleviated mucus secretion. Meanwhile, SP600125 inhibited OVA-induced, increased expression of p-JNK and TLR9 in the lung tissues.

CONCLUSIONS

Collectively, our data demonstrated that SP600125 promoted resolution of allergic airway inflammation via TLR9 in an OVA-induced murine acute asthma model. The JNK-TLR9 pathway may be a new therapeutic target in the treatment for the allergic asthma.

Repeated inhalation of sevoflurane inhibits airway inflammation in an OVA-induced mouse model of allergic airway inflammation

BACKGROUND AND OBJECTIVE

Repeated inhalation of sevoflurane (SVF) can benefit asthmatic patients by bronchodilation. However, the impact of repeated inhalation of SVF on allergic airway inflammation has not been clarified. This study was aimed at investigating the effects of repeated inhalation of SVF on airway inflammation in mice.

METHODS

Female C57BL/6 mice were sensitized with ovalbumin (OVA) and treated by inhalation with SVF or vehicle daily for seven consecutive days, immediately followed by OVA challenge. Airway inflammation was evaluated by counting the numbers of different types of inflammatory infiltrates in bronchoalveolar lavage fluid (BALF), histology, cytokine measurements and mucus production in individual mice.

RESULTS

In comparison with the OVA group, repeated inhalation of SVF significantly reduced the numbers of total cells, eosinophils, lymphocytes, macrophages and neutrophils (P < 0.05 to P < 0.01), and the levels of BALF tumour necrosis factor-α and lung high-mobility group box 1 (P < 0.01), accompanied by elevated levels of BALF interleukin-10 in allergic mice (P < 0.05). Repeat inhalation of SVF decreased the levels of serum OVA-specific immunoglobulin E (IgE) and mitigated allergic airway epithelial goblet cell hyperplasia and mucus hypersecretion in allergic mice (P < 0.01).

CONCLUSIONS

Repeated inhalation of SVF inhibits allergic airway inflammation by reducing inflammatory infiltrates, improving the imbalance of cytokine responses and mitigating allergen-specific IgE responses and goblet cell hyperplasia in mice.

Dezocine prevents sufentanil-induced cough during general anesthesia induction: A randomized controlled trial

BACKGROUND

Opioid-induced cough during induction of general anesthesia is a common phenomenon. Dezocine, a partial μ-receptors agonist and κ-receptors antagonist, has been documented effectively suppressing fentanyl-induced cough in general anesthesia induction. However, the effect of dezocine on sufentanil-induced cough is still unknown.

METHODS

A total of 370 patients (American Society of Anesthesiologists physical status I-II), aged 18-70 years, undergoing elective surgery, were randomly divided into a control group (group C) and a dezocine group (group D) (n=185 in each group). Patients received dezocine 0.1mg/kg or an equal volume of 0.9% normal saline 2 min prior to intravenous sufentanil (0.5 μg/kg). The incidence and reflex degree of cough in patients were evaluated within 2 min after the injection of sufentanil in anesthesia induction period.

RESULTS

No patient in group D had cough and 59 patients in group C had cough (severity of cough: mild, 7%; moderate, 11.4%; severe, 13.5%). The occurrence and reflex degree of cough in group D was significantly lower than that in group C (P=0.000). The highest heart rate (HR) and invasive blood pressure (IBP) values were higher in group C than those in group D (P<0.01) within 2 min after sufentanil administration, althought these values remained within safe limits.

CONCLUSION

The results of current study suggest that administration of Dezocine 0.1mg/kg may effectively prevent the occurrence and reflex degree of sufentanil-induced irritating cough in general anesthesia induction in patients.

Effects of calcitriol and its analogues on interaction of MCP-1 and monocyte derived dendritic cells in vitro

AIM

To study the effect of calcitriol [1,25(OH)2D3] and its analogues on the interaction of monocyte chemoattractant protein-1 (MCP-1) and in vitro generated monocyte-derived dendritic cells (MoDC).

METHODS

MoDC were obtained by differentiating monocytes in exposure to GM-CSF and IL-4 for 5 d. mRNA expression of MCP-1 and its receptors were analyzed by RT-PCR, and protein production of MCP-1 by ELISA and migratory ability of MoDC in response to MCP-1 by a micromultiwell chemotaxis chamber assay.

RESULTS

MoDC can express MCP-1 mRNA, and secret a low level of MCP-1 protein and has the ability to migrate to MCP-1 in corresponding to its expression of MCP-1 receptors. Calcitriol and its analogues with the same affinity to vitamin D receptor up-regulated the gene expression of both MCP-1 and its receptors, enhanced MCP-1 protein production and promoted the migratory ability of MoDC to MCP-1.

CONCLUSION

The interaction of DC and MCP-1 found in this study may suggest a possible auto-regulatory role between DC and MCP-1 and the modulatory effect of calcitriol and its analogues on DC and MCP-1 might provide an understanding of their positive role in tumors.