Theaflavin-3,3'-digallate attenuates cigarette smoke extract-induced pulmonary emphysema in mice by suppressing necroptosis.

Pulmonary emphysema is one of the most important pathological manifestations of chronic obstructive pulmonary disease and is commonly associated with cigarette smoking. Previous studies have indicated that necroptosis, a novel non-apoptotic cell death mechanism associated with inflammation and oxidative stress, may contribute to the development of pulmonary emphysema. Theaflavin-3,3'-digallate (TF-3), one of the theaflavins present in black tea, is known to possess several bioactive properties. In the present study, it was demonstrated that TF-3 significantly reduced the generation of reactive oxygen species and the mRNA expression levels of TNF-α, IL-1ß and IL-6 in CSE-treated human normal lung epithelial BEAS-2B cells. To further explore the role of TF-3 in necroptosis, the necroptotic rates of BEAS-2B cells were examined via flow cytometry and immunofluorescence assays. The results demonstrated that TF-3 may suppress necroptosis in CSE-treated BEAS-2B cells. Furthermore, it was determined that TF-3 significantly inhibited the CSE-induced phosphorylation of p38 MAPK, receptor-interacting serine/threonine-protein kinase three (RIPK3) and mixed lineage kinase domain-like (MLKL) in BEAS-2B cells. Another experiment demonstrated that a pharmacological inhibitor of the p38 MAPK pathway, SB203580, significantly reduced the protein expression levels of phosphorylated (p)-RIPK3 and phosphorylated (p-)MLKL, which indicated that TF-3 suppressed necroptosis via the p38 MAPK/RIPK3/MLKL signaling pathways. In vivo, it was observed that TF-3 treatment significantly attenuated morphological lung injury in mice with CSE-induced emphysema. Moreover, TF-3 significantly reduced the levels of proinflammatory cytokines, TNF-α and IL-1ß and significantly enhanced the antioxidant capacity of the lung tissues in mice with emphysema. TF-3 also significantly inhibited the levels of p-RIPK3 and p-MLKL in the lungs of mice with emphysema. Therefore, the present study indicated that TF-3 may attenuate CSE-induced emphysema in mice by inhibiting necroptosis.

Risk Prediction for Arrhythmias by Heart Rate Deceleration Runs in Patients with Chronic Obstructive Pulmonary Disease.

Purpose: Chronic obstructive pulmonary disease (COPD) is associated with increased incidence of arrhythmias, which has been attributed to autonomic dysregulation. Detection of autonomic function may facilitate stratification of COPD patients with respect to their risk of development of arrhythmias. Patients and Methods: A total of 151 COPD patients and 45 non-COPD patients were included in this study. Heart rate deceleration runs (DRs) were detected by dynamic electrocardiogram (ECG); DRs successively occurring in 2, 4, or 8 cardiac cycles were denoted as DR2, DR4, and DR8, respectively. Indicators of arrhythmias including isolated premature atrial contractions (PAC), supraventricular tachycardia (SVT), isolated premature ventricular contractions (PVC), and ventricular tachycardia (VT) were recorded. Occurrence of SVT or PAC ≥70/day was considered positive for supraventricular arrhythmias, while positive ventricular arrhythmias category (PVAC) was defined as occurrence of VT or PVC ≥10/hour. Results: Compared with non-COPD individuals, COPD patients were associated with increased number of PAC, PVC, higher incidence of PAC >70/d, SVT, PVAC, and decreased DRs (DR2, DR4, DR8) (P<0.05). In COPD patients, DRs showed a negative correlation with the incidence of PAC, PVC, SVT, and PVAC (P<0.05). In receiver operating characteristic curve analysis, all the DRs were found to be significant predictors of PAC >70/d, SVT, and PVAC. The predictive power of DRs was significantly different from one another with the order ranged as DR4>DR8>DR2 for PAC >70/d, DR8>DR4>DR2 for SVT, and DR8>DR4>DR2 for PVAC. Conclusion: Our study provides evidence of significant autonomic dysregulation in COPD patients. DRs may serve as a marker of the risk of arrhythmias in COPD patients.

Cigarette smoke extract increases mitochondrial membrane permeability through activation of adenine nucleotide translocator (ANT) in lung epithelial cells.

Cigarette smoke is one of major risk factors in the pathogenesis of chronic obstructive pulmonary disease (COPD). It is generally believed that cigarette smoke induces mitochondrial damage in the alveolar epithelial cells to contribute to COPD. However, the exact molecular mechanism remains unknown for the mitochondrial damage. In this study, cigarette smoke extract (CSE) was found to induce the mitochondrial membrane permeability (MMP), which promoted proton leakage leading to the reduction in mitochondrial potential and ATP production. ANT in the mitochondrial inner membrane was activated by CSE for the alteration of MMP. The activation was observed without an alteration in the protein level of ANT. Inhibition of the ANT activity with ADP or bongkrekic acid prevented the MMP alteration and potential drop upon CSE exposure. The ANT activation was observed with a rise in ROS production, inhibition of the mitochondrial respiration, decrease in the complex III protein and rise in mitophagy activity. The results suggest that ANT may mediate the toxic effect of cigarette smoke on mitochondria and control of ANT activity is a potential strategy in intervention of the toxicity.

CXCL16 Induces the Progression of Pulmonary Fibrosis through Promoting the Phosphorylation of STAT3.

Aim: The transmembrane chemokine (C-X-C motif) ligand 16 (CXCL16) plays a vital role in the pathogenesis of organ fibrosis, including the liver and kidney. However, the detailed biological function of CXCL16 is still not fully understood in the progression of pulmonary fibrosis (PF). The aim of present study is to examine the function of CXCL16 in PF. Materials and Methods: In this study, we constructed the PF model on mouse by using bleomycin and analyzed the effect of the mouse recombinant protein CXCL16 on mouse lung fibroblast L929 (LF) as well. To further examine the connection between CXCL16 and STAT3 in mouse LF cells, the STAT3 inhibitor AG490 was utilized to inhibit the expression of STAT3. Meanwhile, lipopolysaccharide was used to enhance the phosphorylation of STAT3 (p-STAT3) in mouse LF cells. Results: Our results indicated that the level of CXCL16/CXCR6 was significantly upregulated in the mouse PF model. Moreover, the level of p-STAT3 was also promoted. In addition, the mouse recombinant protein CXCL16 not only contributed to the proliferation of mouse LF cells but also induced the expression of p-STAT3 in LF cells. However, the effect of CXCL16 was deeply abolished by the STAT3 inhibitor AG490 in LF cells. Meanwhile, the antibody of CXCL16 deeply reduced the phosphorylation of STAT3 in lipopolysaccharide (LPS) cultured cells. Conclusions: All these results demonstrated that CXCL16 promoted the phosphorylation of STAT3 and further demonstrated that STAT3 was a critical component in CXCL16/CXCR6 signaling pathway. This research not only enhanced the comprehension of CXCL16 but also indicated its potential value as a target in the treatment for human PF.

Downregulation of Sfrp5 in insulin resistant rats promotes macrophage-mediated pulmonary inflammation through activation of Wnt5a/JNK1 signaling.

BACKGROUND: Insulin resistance (IR), a common co-morbidity of chronic obstructive pulmonary disease (COPD), aggravates airway inflammation in COPD patients, but its mechanism is unclear. Sfrp5, a novel anti-inflammatory adipocytokine, inhibits macrophage-mediated inflammation of adipose tissue and abrogates IR. However, few studies have been conducted on the regulatory role of Sfrp5 in lung inflammation. METHODS: In the present study, 30 SD rats were divided into two groups: the normal food (NF) group and the high-fat diet (HFD) group. Oral glucose tolerance test (OGTT) and insulin release test were performed to assess whether a successful IR rat model was established. The expression of Sfrp5 and key downstream moleculars of Wnt5a/JNKl signaling was detected. Lung tissue pathomorphology and macrophage activation were observed. In addition, we counted the number of inflammatory cells and measured inflammatory cytokines in bronchoalveolar lavage fluid (BALF). In vitro, rat lung macrophages were isolated and treated with Wnt5a, Sfrp5, and/or JNK inhibitor SP600125. JNK activity and inflammatory cytokines expression were examined. RESULTS: We found that in a rat model of IR, Sfrp5 expression of lung tissue was downregulated, while the Wnt5a/JNKl pathway was activated and the lung inflammatory response was enhanced. Meanwhile, Sfrp5 significantly suppressed Wnt5a/JNKl-induced macrophage activation. CONCLUSIONS: Collectively, IR reduces Sfrp5 expression of lung tissue and activates the Wnt5a/JNK1 pathway, promoting macrophage activation and contributing to the lung's inflammatory response. In contrast, Sfrp5 suppresses the inflammatory response by inhibiting the Wnt5a/JNKl pathway, which could be a target of treatment of COPD.

Aging increases the expression of lung CINCs and MCP-1 in senile patients with pneumonia.

OBJECTIVE: To explore the relationship between aging and the expression of monocyte chemoattractant protein (MCP) and cytokine-induced neutrophil chemoattractant (CINCs) in patients with pneumonia. RESULTS: Bacteria counts in senile group were significantly higher than non-senile group, and while white blood cell and neutrophil counts in senile group were observably lower than non-senile group. The concentration of MCP-1 was significantly higher in senile group compared with the non-senile group, and the expression of CINC-1 and CINC-2α was also higher in senile group. In all patients with different pathogens, expression of all the factors was significantly higher in senile group compared with the non-senile group. What's more, expression of MCP-1, CINC-1 and CINC-2α showed significant difference in some patients with different pathogens. CINC-2ß and CINC-3 expression was not detected in both groups. MATERIALS AND METHODS: The present study included 800 patients with pneumonia who were hospitalized to the Department of Respiratory Medicine in Tongji Hospital during the period from December of 2014 to June of 2016. All patients were divided into two groups: senile pneumonia and non-senile pneumonia group. Bacteria, white blood cell and neutrophil counts were determined by automatic blood cell analyzer. The expression of MCP-1, CINC-1, CINC-2α, CINC-2ß and CINC-3 was determined by ELISA assay. CONCLUSIONS: Aging can increase the expression of MCP-1,CINC-1 and CINC-2α in patients with pneumonia, which may lead to increased risk of pneumonia in the elderly.

Cardiac autonomic function in patients with acute exacerbation of chronic obstructive pulmonary disease with and without ventricular tachycardia.

BACKGROUND: Autonomic dysfunction in patients with chronic obstructive pulmonary disease (COPD) may increase the risks of arrhythmia and sudden death. We studied cardiac autonomic function in patients with acute exacerbation of COPD (AECOPD). METHODS: Patients with AECOPD were classified into ventricular tachycardia (VT) and non-VT groups according to the presence or absence of VT. The following parameters derived from 24-h Holter monitoring were compared between groups: average heart rate, heart rate deceleration capacity (DC), heart rate acceleration capacity (AC), standard deviation of normal RR intervals (SDNN), standard deviation of average RR interval in 5-min segments (SDANN), root mean square of standard deviations of differences between adjacent normal RR intervals (rMSSD), low-frequency power (LF), high-frequency power (HF) and LF/HF ratio. RESULTS: Seventy patients were included, 22 in the VT group and 48 in the non-VT group. The groups had similar clinical characteristics (except for more common amiodarone use in the VT group, P < 0.05) and general ECG characteristics. DC, SDNN, SDANN and rMSSD were lower and AC higher in the VT group (P < 0.05). In the VT group, DC was correlated positively with SDNN (r = 0.716), SDANN (r = 0.595), rMSSD (r = 0.571) and HF (r = 0.486), and negatively with LF (r = -0.518) and LF/HF (r = -0.458) (P < 0.05). AC was correlated negatively with SDNN (r = -0.682), SDANN (r = -0.567) and rMSSD (r = -0.548) (P < 0.05). CONCLUSIONS: DC decreased and AC increased in patients with AECOPD and VT, reflecting an imbalance in autonomic regulation of the heart that might increase the risk of sudden death.

Severe pneumonia in the elderly: a multivariate analysis of risk factors.

Pneumonia is the second leading reason for hospitalization of medicare beneficiaries. The mortality rate is high, especially in the elderly. In this study, we aimed to determine the risk factors associated with severe pneumonia in the elderly. Retrospective study was conducted and data of old patients with severe pneumonia were collected. They were divided into two groups: the experiment group (death group) and the control (living group). The general situation, underlying diseases, laboratory tests, types of etiology, imaging analysis and treatment situation of patients were analyzed and compared. Univariate analysis and logistic multivariate regression analysis were used to screen the related and independent risk factors for the diagnosis of severe pneumonia in the elderly. In univariate analysis, there were many factors had statistical significance including chronic kidney disease, electrolyte disturbance, low phosphorus and so on. Result of logistic multivariate regression analysis showed pro-BNP level and serum prealbumin were independent risk factors. In sputum culture, the relevance ratio of acinetobacter baumannii was the highest in gram negative bacteria followed by klebsiella pneumoniae. In gram positive bacteria, the relevance ratio of staphylococcus aureus was the highest. In conclusion, the analysis on risk factors for severe pneumonia has great clinical significance on improving the prognosis.

Serum iron and A(2)DS(2) score in stroke-associated pneumonia.

To evaluate the efficacy of serum biomarkers such as iron, procalcitonin (PCT), C-reactive protein (CRP) and A(2)DS(2) scores at hospital admission to predict the onset and severity of stroke-associated pneumonia (SAP), 101 patients with acute stroke were selected and divided into the control and SAP group. Compared with control group, no significant differences were discovered in age, sex, vascular risk factors including hypertension, diabetes and hyperlipidemia, chronic lung disease of SAP group, while a significantly higher level was found in incidence of dysphagia, NIHSS score, A(2)DS(2) score, CURB-65 score, serum iron, serum ferritin, PCT and CRP (P < 0.01). The receiver operating characteristic curve showed that serum iron, serum ferritin, PCT, CRP, A(2)DS(2) score and CURB-65 score had relatively high values in the SAP prediction (all P < 0.01, all AUC > 0.5). When combined ferritin, PCT, and A(2)DS(2) scores and other indicators with CRP for SAP prediction, the model had a larger area under the curve (AUC) and higher specificity than individual prediction models. Spearman regression analysis presented that serum iron, serum ferritin and A(2)DS(2) score were highly correlated with CURB-65 score (P < 0.01). It was suggested that Serum iron and A(2)DS(2) score measured at admission were effective indicators in SAP prediction which could be used for SAP screening and severity prediction. Besides, the specificity in SAP prediction could be improved when Serum iron and A(2)DS(2) score combined with CRP.

Aging reduces the expression of lung CINC and MCP-1 mRNA in a P. aeruginosa rat model of infection.

We investigated dynamic changes of inflammatory cell infiltration and expression of cytokine-induced neutrophil chemoattractant (CINC) and monocyte chemoattractant protein-1 (MCP-1) mRNA in aged rats with Pseudomonas aeruginosa pulmonary infection. Disease manifestation and lung tissue pathology (lesion dispersion, inflammatory reactions, tissue edema and bleeding) were more severe in aged rats than young rats. At various time points, lung tissue polymorphonuclear neutrophil and mononuclear macrophage numbers were lower in the aged group than the young group (P < 0.05), and at 24 h there was no difference in mononuclear macrophage numbers. After inoculation with P. aeruginosa, CINC and MCP-1 mRNA expression increased in both groups, but the peak lagged in old rats compared with young. Thus, aging can reduce the expression of CINC and MCP-1 mRNA in lung tissues, and reduce the infiltration of neutrophils and monocyte-macrophages induced by CINC and MCP-1. This might lead to increased risk of pneumonia in elderly patients.

Age-specific Mycoplasma pneumoniae pneumonia-associated myocardial damage in children.

OBJECTIVE: To measure Mycoplasma pneumoniae pneumonia (MPP)-associated myocardial damage in different age groups of children with pneumonia. METHODS: Children aged 0-14 years with pneumonia and myocardial damage (serum creatine kinase isoenzyme-MB [CK-MB] concentration >25 U/l) were enrolled in the study. The children were classified as Mycoplasma pneumoniae immunoglobulin M positive (M. pneumoniae IgM+) or negative (M. pneumoniae IgM-) based on a serological test. Children were stratified into four age groups in order to analyse age-specific MPP-associated myocardial damage. RESULTS: The incidence of fever was significantly higher in children who were M. pneumoniae IgM+ compared with M. pneumoniae IgM- children. The median serum CK-MB concentration was significantly higher in children who were M. pneumoniae IgM+ compared with those who were M. pneumoniae IgM-. Children who were M. pneumoniae IgM+ in the 13-36 months and 72 months-14 years age groups had significantly higher median serum CK-MB concentrations than those who were M. pneumoniae IgM- in the same age group. CONCLUSIONS: M. pneumoniae infection was associated with greater myocardial damage in children aged 13-36 months and 72 months-14 years. This suggests age-specific immune responses to M. pneumoniae.

Effect of glutamine on apoptosis of intestinal epithelial cells of severe acute pancreatitis rats receiving nutritional support in different ways.

OBJECTIVE: To investigate the effect of glutamine (Gln) on pro-inflammatory cytokines (TNF-α, IL-2 and IL-10) and the balance between pro-inflammatory cytokines and anti-inflammatory cytokines in severe acute pancreatitis (SAP) rats receiving nutritional support in different ways. METHODS: Male SD rats (n=80) were randomly assigned into 5 groups: sham group, SAP+ parenteral nutrition (PN) group, SAP+ enteral nutrition (EN) group, SAP+EN+Gln group and SAP+PN+Gln group. At the same time, rats in 5 groups were sacrificed at 4 and 7 days after nutritional support. ELISA was employed to detect the pro-inflammatory cytokines including TNF-α, IL-2 and IL-10. RESULTS: The serum TNF-α in the EN+Gln group after 7-day treatment was significantly lower than that in the EN, PN and PN+Gln groups at corresponding time point (P<0.05). The serum IL-2 in the EN+Gln group after 7-day treatment was markedly higher than that in the EN, PN and PN+Gln groups at corresponding time point (P<0.01). After 7-day treatment, the serum IL-2 in the EN+Gln and EN groups were markedly higher than that after 4-day treatment (P<0.01), but the serum IL-2 in the PN group was significantly lower than that after 4-day treatment (P<0.01). The serum IL-10 after 7-day treatment was markedly lower than that after 4-day treatment in all groups (P<0.01), and PN group had the lowest serum IL-10. Serum IL-10 in the EN+Gln group was significantly higher than that in the PN and PN+Gln groups at both time points (P<0.01). The serum IL-10 in the EN group was significantly higher than that in the PN group after 4-day treatment (P<0.01), but the serum IL-10 in the EN group was comparable to that in the PN group after 7-day treatment. The serum IL-10/TNF-α in the EN+Gln group was only slightly higher than that in the control group at both time points. The serum IL-10/TNF-α in the EN group was significantly lower than that in the EN+Gln group at both time points (P<0.05). The serum IL-10/TNF-α in the PN group was markedly lower than that in the EN group and EN+Gln group (P<0.05 and P<0.01, respectively). CONCLUSION: EN in combination with Gln are superior to EN alone, PN alone and PN in combination with Gln in regulating inflammation in SAP rats, and the EN has more potent capability to regulate the balance between pro-inflammation and anti-inflammation than PN.

Transplanted bone marrow stromal cells improve cognitive dysfunction due to aging hypoperfusion in rats.

BACKGROUND: Aging is an important risk factor for vascular dementia, and D-galactose (D-gal) injection can simulate the pathology of aging. Two-vessel occlusion of common carotid arteries (2VO) is the most popular model for vascular dementia. This study was aimed to investigate the possibility of D-gal injection plus 2VO simulating cognitive impairment of aging vascular dementia; and whether transplanted bone marrow stromal cells (BMSCs) can improve the cognitive function induced by D-gal injection plus 2VO. METHODS: Totally 30 male Sprague-Dawley rats were divided into 5 groups equivalently: control group, D-gal group, D-gal + 2VO group, D-gal + 2VO + saline water group, and D-gal + 2VO + BMSCs group. Aging hypoperfusion rats were created by subcutaneous injection of D-gal and occlusion of two common carotid arteries. BMSCs or saline water was stereotactically transplanted into the subventricular zone as treatment vehicles at 24 hours post operation. Two-way repeat analysis of variance (ANOVA) was used for significance analysis of 5 groups at 6 weeks post transplantation; moreover, Tamhane's test (equal variance not assumed) and least significant difference (LSD) test (equal variance assumed) were used for pairwise comparison in Morris water maze (MWM). RESULTS: Transplanted BMSCs distributed around the lateral ventricles and acquired the phenotypes of neurons and astrocytes. In terms of swimming path distance and escape latency in MWM, D-gal + 2VO + BMSC group showed significant improvement than the D-gal + 2VO group but was still obviously worse than the control group (both P < 0.05). There was no significant difference in swimming speed for all 5 groups. CONCLUSIONS: D-gal plus 2VO induces cognitive dysfunction. The engrafted BMSCs exhibit the beneficial effect on cognitive function via promotion interactively with host brain.