Mesenchymal stem cell-derived exosomal miR-548x-3p inhibits pyroptosis of vascular endothelial cells through HMGB1 in heat stroke.

Heat stroke (HS) is an acute physical illness associated with a higher risk of organ dysfunction. This study is the first to explore exosomal miR-548x-3p derived from human bone marrow mesenchymal stem cells (BMSCs) in the pyroptosis of vascular endothelial cells (VECs) associated with HS. Human BMSCs-derived exosome alleviated the injury of the heart, liver, kidney and ileum tissues, the increase of IL-1ß, IL-18 and TNF-α levels, pyroptosis of endothelial cells and the increase of HGMB1, NLRP3, ASC, caspase1 and GSDMD-N protein expression in HS mice and HS-induced human umbilical vein endothelial cells (HUVECs). miR-548x-3p was down-expressed in HS patients, while up-expressed in BMSCs-derived exosome. BMSCs-ExomiR-548x-3p mimics to inhibit pyroptosis, inflammation and HGMB1/NLRP3 activation in HS-induced HUVECs and HS mice, which were blocked by overexpression of HMGB1. In conclusion, human BMSCs-derived exosomes carried miR-548x-3p mimics to inhibit pyroptosis of VECs through HMGB1 in HS mice.

Ginsenoside-Rg1 attenuates sepsis-induced cardiac dysfunction by modulating mitochondrial damage via the P2X7 receptor-mediated Akt/GSK-3ß signaling pathway.

Ginsenoside-Rg1 (G-Rg1), a saponin that is a primary component of ginseng, is effective against inflammatory diseases. The P2X purinoceptor 7 (P2X7) receptor is an ATP-gated ion channel that is predominantly expressed in immune cells and plays a key role in inflammatory processes. We investigated the role of G-Rg1 in sepsis-related cardiac dysfunction and the underlying mechanism involving the regulation of the P2X7 receptor. We detected cell viability, cytotoxicity, cellular reactive oxygen species (ROS) levels, and mitochondrial membrane potential (MMP) with or without G-Rg1 in lipopolysaccharide (LPS)- or hypoxia/reoxygenation (H/R)-induced H9c2 cell models of ischemia/reperfusion injury. We applied cecal ligation and puncture (CLP) to induce a mouse model of sepsis and measured the survival duration and cardiac function of CLP mice. Next, we quantified the ROS level, MMP, respiratory chain complex I-IV enzymatic activity, and mitochondrial fusion in CLP mouse heart tissues. We then investigated the role of G-Rg1 in repairing LPS-induced cell mitochondrial damage, including mitochondrial superoxidation products. The results showed that G-Rg1 inhibited LPS- or H/R-induced cardiomyocyte apoptosis, cytotoxicity, ROS levels, and mitochondrial damage. In addition, G-Rg1 prolonged the survival time of CLP mice. G-Rg1 attenuated LPS-induced superoxide production in the mitochondria of cardiomyocytes and the excessive release of cytochrome c from mitochondria into the cytoplasm. Most importantly, G-Rg1 suppressed LPS-mediated induction of proapoptotic Bax, activated Akt, induced GSK-3ß phosphorylation, and balanced mitochondrial calcium levels. Overall, G-Rg1 activates the Akt/GSK-3ß pathway through P2X7 receptors to inhibit sepsis-induced cardiac dysfunction and mitochondrial dysfunction.

Emerging protective roles of shengmai injection in septic cardiomyopathy in mice by inducing myocardial mitochondrial autophagy via caspase-3/Beclin-1 axis.

BACKGROUND: Sepsis, a life-threatening systemic syndrome related to inflammatory response, usually accompanied by major organ dysfunctions. The aim of the present study was to elucidate the role by which Shengmai injection (SMI) acts to septic cardiomyopathy. METHODS: Initially, the induced mice with septic cardiomyopathy were treated with SMI or normal saline (NS) with oe-caspase-3, and HL-1 cells were treated with oe-Beclin-1 and oe-caspase-3 and then cultured with lipopolysaccharide (LPS). Subsequently, we measured the cardiac troponin I (cTnI) level, and expression of mitochondrial autophagy protein (parkin and pink1) and myocardial cell autophagy-related proteins (LC3-II and LC3-I). Additionally, we identified the cleavage of Beclin-1 by caspase-3 and detected the changes of mitochondrial membrane potential, level of reactive oxygen species (ROS), and apoptosis of myocardial cells in myocardial tissues of mice. RESULTS: It has been demonstrated that SMI contributed to the increase of myocardial mitochondrial autophagy, reduction of cTnI level, and elevation of mitochondrial membrane potential in septic cardiomyopathy mice. Both in vitro and in vivo experiments showed that caspase-3 promoted cleavage of Beclin-1 and release of ROS, whereas repressed lipopolysaccharide (LPS)-induced mitochondrial autophagy. Furthermore, the facilitation of myocardial mitochondrial autophagy and protection of myocardial mitochondria by SMI through inhibition of cleavage Beclin-1 by caspase-3 in septic cardiomyopathy mice were also proved by in vivo experiments. CONCLUSION: Taken together, SMI could protect myocardial mitochondria by promoting myocardial mitochondrial autophagy in septic cardiomyopathy via inhibition of cleavage of Beclin-1 by caspase-3. Our study demonstrates that SMI could represent a novel target for treatment of septic cardiomyopathy.

Pyroptosis of HUVECs can be induced by heat stroke.

Heat stroke is a serious pathological condition with high mortality. Vascular endothelial cell injury is a key feature in the pathogenesis of heat stroke, but the specific pathophysiological process whereby this occurs is still unclear. Currently, relevant studies are primarily based upon examination of apoptosis. Recently, pyroptosis, a new form of inflammation-related programmed cell death, was also demonstrated to be involved in heat stroke pathophysiology. Herein, we present evidence that vascular endothelial cell pyroptosis can be induced by heat stress in a time- and temperature-dependent manner. Furthermore, this process can be significantly inhibited by GSDMD siRNA. These findings suggest a new therapeutic target for heat stroke.

A novel release kinetics evaluation of Chinese compound medicine: Application of the xCELLigence RTCA system to determine the release characteristics of Sedum sarmentosum compound sustained-release pellets.

Purpose: To establish a novel release kinetics evaluation method of Chinese compound medicine (Sedum Sarmentosum compound) with xCELLigence Real-Time Cell-based Assay (RTCA) system. Methods: Cell lines sensitive to Sedum Sarmentosum compound are screened, and cell index-time (CI-T) graphs and cell index release kinetics models are established based on the cell index (CI) monitored. The methodological studies of precision and repeatability were processed by the cell monitors system. The release profiles of the sustained-release Sedum Sarmentosum compound were determined. Consequently, the sustained-release property was characterized by the kinetic parameters based on the cell-index. Results: The accumulative release rate based on cell index of Sedum sarmentosum compound sustained-release preparation was determined and it had a good correlation with time, fitting better with First-order model, Higuchi model and Ritger-Peppas model, and fitting best with Weibull model. It indicated that the release rate is proportional with the diffusion coefficient. Conclusion: The new method of cell-index release kinetics may provide a quantitative description for the release of the multi active agents from Traditional Chinese Medicines. The application of xCELLigence RTCA system for evaluating the release kinetics of Chinese compound medicine is feasible.

Litoamentenes A-K, eleven undescribed cembranoids with cytotoxicity from the South China Sea soft coral Litophyton amentaceum.

Eleven undescribed cembrane-type diterpenoids, named litoamentenes A-K (1-11), were isolated from the soft coral Litophyton amentaceum collected from the South China Sea. Their structures were elucidated by extensive analysis of spectroscopic data, comparison with the literature data, single crystal X-ray diffraction, quantum chemical calculations and TDDFT-ECD calculations. This is the first systematic investigation of L. amentaceum. In particular, compounds 1-3 are cembrane-type norditerpenoids that lack isopropyl side chains. Compound 6 is a cembrane-type norditerpenoid without a methyl group at C-4, the first natural product identified with this carbon skeleton. Compounds 6, 9 and 10 showed modest cytotoxicity against several human cancer cell lines with IC50 values ranging from 3.99 to 14.56 µM.

Untargeted metabolomic profiling of sepsis-induced cardiac dysfunction.

Objective: Sepsis is a life-threatening condition secondary to infection that evolves into a dysregulated host response and is associated with acute organ dysfunction. Sepsis-induced cardiac dysfunction is one of the most complex organ failures to characterize. This study performed comprehensive metabolomic profiling that distinguished between septic patients with and without cardiac dysfunction. Method: Plasma samples collected from 80 septic patients were analysed by untargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics. Principal component analysis (PCA), partial least squares discrimination analysis (PLS-DA), and orthogonal partial least square discriminant analysis (OPLS-DA) were applied to analyse the metabolic model between septic patients with and without cardiac dysfunction. The screening criteria for potential candidate metabolites were as follows: variable importance in the projection (VIP) >1, P < 0.05, and fold change (FC) > 1.5 or < 0.7. Pathway enrichment analysis further revealed associated metabolic pathways. In addition, we constructed a subgroup metabolic analysis between the survivors and non-survivors according to 28-day mortality in the cardiac dysfunction group. Results: Two metabolite markers, kynurenic acid and gluconolactone, could distinguish the cardiac dysfunction group from the normal cardiac function group. Two metabolites, kynurenic acid and galactitol, could distinguish survivors and non-survivors in the subgroup analysis. Kynurenic acid is a common differential metabolite that could be used as a candidate for both diagnosis and prognosis for septic patients with cardiac dysfunction. The main associated pathways were amino acid metabolism, glucose metabolism and bile acid metabolism. Conclusion: Metabolomic technology could be a promising approach for identifying diagnostic and prognostic biomarkers of sepsis-induced cardiac dysfunction.

Effect of Insulin Receptor on Juvenile Hormone Signal and Fecundity in Spodoptera litura (F.).

Insulin signaling can regulate various physiological functions, such as energy metabolism and reproduction and so on, in many insects, including mosquito and locust. However, the molecular mechanism of this physiological process remains elusive. The tobacco cutworm, Spodoptera litura, is one of the most important pests of agricultural crops around the world. In this study, phosphoinositide 3-kinase (SlPI3K), protein kinase B (SlAKT), target of rapamycin (SlTOR), ribosomal protein S6 kinase (SlS6K) and transcription factor cAMP-response element binding protein (SlCREB) genes, except transcription factor forkhead box class O (SlFoxO), can be activated by bovine insulin injection. Then, we studied the influence of the insulin receptor gene (SlInR) on the reproduction of S. litura using RNA interference technology. qRT-PCR analysis revealed that SlInR was most abundant in the head. The SlPI3K, SlAKT, SlTOR, SlS6K and SlCREB genes were decreased, except SlFoxO, after the SlInR gene knockdown. Further studies revealed that the expression of vitellogenin mRNA and protein, Methoprene-tolerant gene (SlMet), could be down-regulated by the injection of dsRNA of SlInR significantly. Furthermore, a depletion in the insulin receptor by RNAi significantly decreased the content of juvenile hormone III (JH-III), total proteins and triacylgycerol. These changes indicated that a lack of SlInR could impair ovarian development and decrease fecundity in S. litura. Our studies contribute to a comprehensive insight into reproduction, regulated by insulin and the juvenile hormone signaling pathway through nutrition, and a provide theoretical basis for the reproduction process in pest insects.

Early predictive value of platelet function for clinical outcome in sepsis.

OBJECTIVE: Sepsis is the leading course of morbidity and mortality in critically ill patients. This study aimed to evaluate the predictive value of the platelet aggregation for mortality in patients with sepsis. In addition, the relationship between impaired mitochondria and the platelet aggregation was explored. METHOD: This was a prospective, observational cohort study. The platelet aggregation rate in response to adenosine diphosphate (ADP) was assessed. The primary outcome was 28-day mortality. Platelet mitochondrial parameters, including adenosine triphosphate(ATP), mitochondrial membrane potential (MMP) and mitochondrial permeability transition pore (mPTP) opening, were measured. Platelet mitochondrial ultrastructure was observed using transmission electron microscopy. RESULTS: 86 patients with 65 survivors and 21 non-survivors were enrolled. Platelets of non-survivors with sepsis were hyporesponsive to ADP, in terms of maximal aggregation rate (P < 0.001). Receiver operating characteristic curves analysis demonstrated that the AUC estimated 28-day mortality for platelet aggregation rate was 0.814. At the optimal cut-off value of 35.8% for platelet aggregation rate, the sensitivity was 86.2% and the specificity was 66.7%. Kaplan-Meier analysis showed that a platelet aggregation rate of less than 35.8% was associated closely with poor survival. After adjusting for lactate by Cox regression analysis, platelet aggregation rate was identified as an independent predictor for the probability of 28-day mortality. Compared with survivors, non-survivors showed a significant reduction in platelet ATP and MMP-index (both P < 0.001), and a remarkable increase in mPTP opening (P < 0.001). ATP and MMP-index were positively correlated with platelet aggregation rate (R square=0.75, R square=0.44, respectively). CONCLUSION: Platelet aggregation rate could be an early predictive biomarker for mortality in sepsis. Impaired platelet mitochondrial activity affects platelet aggregation and correlates with the severity of sepsis.

CCAAT/Enhancer-Binding Protein Homologous Protein (CHOP) Deficiency Attenuates Heatstroke-Induced Intestinal Injury.

The intestine is one of the main target organs involved in the pathological process of heatstroke. CCAAT/enhancer-binding protein homologous protein (CHOP) is involved in endoplasmic reticulum (ER) stress-induced apoptosis. This study aimed to explore the role of CHOP in heatstroke-induced intestinal injury and potential therapy. An in vitro heat stress (HS) model using Caco-2 cells was employed. We observed the role of CHOP in apoptosis-mediated intestinal epithelial cell injury secondary to HS by evaluating cell viability, lactate dehydrogenase release, apoptosis levels, and GRP78, PERK, ATF4, CHOP, Bcl-2, and BAX mRNA and protein expression. To further study the role of CHOP in HS-induced intestinal barrier dysfunction, we assessed transepithelial electrical resistance, paracellular tracer flux, ultrastructure of tight junctions, and protein expression of ZO-1 and occludin. Male wild-type mice and CHOP knockout mice were used for in vivo experiments. We evaluated serum d-lactate and diamine oxidase levels, histopathological changes, intestinal ultrastructure, and ZO-1 and occludin protein expression. HS activated the PERK-CHOP pathway and promoted apoptosis by upregulating BAX and downregulating Bcl-2; these effects were prevented by CHOP silencing. Intestinal epithelial barrier function was disrupted by HS in vitro and in vivo. CHOP silencing prevented intestinal barrier dysfunction in Caco-2 cells, whereas CHOP knockout mice exhibited decreased intestinal mucosal injury. The ER stress inhibitor 4-phenylbutyrate (4-PBA) prevented HS-induced intestinal injury in vitro and in vivo. This study indicated that CHOP deficiency attenuates heatstroke-induced intestinal injury and may contribute to the identification of a novel therapy against heatstroke associated with the ER stress pathway.

[The effects of Tumstatin185-191 on lung adenocarcinoma cell lines and the association with protein kinase B and extracellular regulated protein kinase activation].

OBJECTIVE: to investigate the antitumor effects of tumstatin185-191 as a single agent or combination with cisplatin (DDP) on non-small lung cancer (NSCLC) cell lines A549. In addition, the changes of the protein kinase B(Akt) and extracellular regulated protein kinase (ERK) in cultured NSCLC cells treated by tumstatin185-191 and cisplatin were evaluated. METHODS: A549 cells were treated with tumstatin185-191 and cisplatin. Cell viability was assessed using the modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell apoptosis was measured by flow cytometry. The activation of Akt and Erk were evaluated by Western blotting. RESULTS: Tumstatin185-191 inhibited the proliferation of A549 and the IC(50) values of tumstatin 185-191 was 73.7 micromol/L. After cotreatment with 20 micromol/L tumstatin185-191, IC(50) values of cisplatin in A549 cells reduced from 5.2 micromol/L to 3.5 micromol/L, while 40 micromol/L tumstatin185-191 reduced from 5.2 micromol/L to 1.4 micromol/L. The early apoptosis rate was (19.34 +/- 0.97)% in the cotreatment group, (12.5 +/- 2.1)% in cisplatin group and (9.6 +/- 1.6)% in tumstatin185-191 group (F = 5.74, P < 0.01). The levels of phospho-Akt (p-Akt) and phospho-ERK (p-ERK) in the A549 cells were remarkably lower after being treated with tumstatin 185-191, while tumstatin 185-191 treatment whether alone, or in combination with cisplatin, had the similar effects on the protein levels of p-Akt and p-ERK in A549 cells. CONCLUSION: our data suggest that tumstatin185-191 might enhance the sensitivity of A549 cells to cisplatin. The effects of promoting apoptosis and downregulation of proliferation induced by tumstatin185-191 may be mediated through inactivation of the Akt and ERK pathways.

[Activation of NOD like receptor protein 3 signaling pathway in vascular endothelial cells induced by heat stress can be inhibited by ethyl pyruvate].

OBJECTIVE: To investigate whether the activation of NOD like receptor protein 3 (NLRP3) signaling pathway in vascular endothelial cells induced by heat stress (HS) could be inhibited by ethyl pyruvate (EP). METHODS: Human umbilical vein endothelial cells (HUVEC) were cultured in vitro, and the cells in logarithmic growth phase were taken to carry out experiment. Different temperatures gradients (39, 41, 43 centigrade for 4-hour HS) and different duration gradients (43 centigrade continuously HS respectively for 2, 3, 4 hours) were set up respectively. For HS group, HUVECs were placed in incubators with corresponding different conditions to carry out HS, then 43 centigrade persisting for 4-hour HS (43 centigrade, 4 hours) was selected as the final experimental condition; during HS, EP 10 mmol/L was added. For control group, the cells were synchronously cultured in 37 centigrade cell incubator. The protein expression of NLRP3 in HUVEC and activity of aspartate specific cysteine protease 1 (caspase-1) were detected with Western blotting; enzyme linked immunosorbent assay (ELISA) was used to detect the released levels of interleukins (IL-18 and IL-1ß) in the cell culture supernatant fluid after HS. RESULTS: After HS, the protein expression level of NLRP3 in HUVEC was increased with the increasing of HS temperature or extension of exposure duration in HS condition, and reached to the highest in 43 centigrade for 4 hours. Compared with control group, there was significant difference [NLRP3 protein expression (NLRP3/GAPDH): 1.54±0.08 vs. 0.97±0.17, P < 0.05]; after EP intervention, the expression of NLRP3 and the activation of caspase-1 in HUVEC were significantly lower than those in HS group [NLRP3 protein expression (NLRP3/GAPDH): 1.15±0.07 vs. 1.57±0.09, caspase-1 activity: 40.87±6.54 vs. 59.75±9.92, both P < 0.05], moreover, the released levels of IL-18 and IL-1ß in cell supernatant were also significantly decreasing than those in HS group [IL-18 (ng/L): 1.09±0.08 vs. 1.41±0.13, IL-1ß (ng/L): 1.38±0.10 vs. 2.02±0.10, both P < 0.05]. CONCLUSIONS: The activation of NLRP3 signaling pathway in vascular endothelial cells induced by HS could be significantly inhibited by EP, which helps to reduce the release of inflammatory cytokines from vascular endothelial cells induced by HS.

4-Phenylbutyrate Prevents Endoplasmic Reticulum Stress-Mediated Apoptosis Induced by Heatstroke in the Intestines of Mice.

OBJECTIVE: Heatstroke can induce serious physiological dysfunction in the intestine. However, the underlying mechanisms of this condition are unknown, and therapeutic strategies are not available. In this study, we explored the role of endoplasmic reticulum (ER) stress signaling in this process and assessed whether pretreating mice with an inhibitor of ER stress could alleviate intestinal damage. METHODS: A heatstroke model was established in male mice. Mice were pretreated with 4-phenylbutyrate (4-PBA) before exposure to heat stress. Intestinal morphological changes were observed by hematoxylin and eosin (H&E) staining and transmission electron microscopy. The TUNEL assay was used to detect intestinal apoptosis. The expression of the ER stress-related proteins and apoptosis-related proteins was investigated by the Western blot assay. RESULTS: Compared with control group, mice with heatstroke exhibited evidence of intestinal injury and epithelial apoptosis, accompanied by significantly increased expression of ER stress-related proteins in the intestines. The intestinal injury score and level of intestinal epithelial apoptosis were significantly reduced after administration of 4-PBA. Furthermore, the levels of the intestinal ER stress-related proteins GRP78, PERK, p-eIF2α, ATF4, and CHOP were decreased after 4-PBA treatment. CONCLUSIONS: Our results indicate that the ER stress-mediated apoptosis pathway is activated during heat stress-induced intestinal injury. 4-PBA can inhibit heatstroke-induced intestinal ER stress and attenuate intestinal injury. We provide evidence that the beneficial effect of 4-PBA is closely related to the inhibition of ER stress-mediated apoptosis. These findings suggest that ER stress may be a novel therapeutic target in patients with heatstroke.

[Tumstatin185-191 increases the sensitivity to cisplatin in a cisplatin-resistant human lung adenocarcinoma cell line].

OBJECTIVE: To investigate the effects and related mechanisms of Tumstatin 185-191 as a single agent or in combination with cisplatin on proliferation and apoptosis in a cisplatin-resistant human lung adenocarcinoma cell line A549-DDP cells. METHODS: A549-DDP cells were treated with Tumstatin185-191 and cisplatin at varying concentrations. Cell viability was assessed by a modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. 50% inhibiting concentration (IC(50)) values of the chemotherapeutic drugs were analyzed by MTT assay. Cell apoptosis was measured by flow cytometry. The activation of Akt and ERK was evaluated by Western blotting. RESULTS: Tumstatin185-191 inhibited the proliferation of A549-DDP cells and its IC(50) value was 80.25 micromol/L. After cotreatment with 20 micromol/L Tum185-191, the IC(50) value of cisplatin in A549-DDP cells reduced from 77.16 micromol/L to 57.97 micromol/L, the reverse index was 1.33, while with 40 micromol/L Tumstatin185-191 the IC(50) was reduced from 77.16 to 26.40 micromol/L and the reverse index was 2.92. The early apoptosis rate was 19.5% +/- 1.1% in the cotreatment group, while 13.3% +/- 1.5% in cisplatin group and 10.2% +/- 2.0% in Tum185-191 group (F = 4.09, P < 0.05). The levels of phospho-Akt (p-Akt) and phospho-ERK (p-ERK) in the A549-DDP cells were remarkably lower after treatment with Tumstatin 185-191. The Tumstatin 185-191 treatment alone or in combination with cisplatin had a similar effect on the protein levels of p-Akt and p-ERK in A549-DDP cells. CONCLUSION: Our data suggest that Tumstatin185-191 may promote apoptosis, downregulate proliferation and partly reverse the drug resistance of A549-DDP cells to cisplatin. The effects induced by Tum185-191 may be mediated through inactivation of the Akt and ERK pathways.

[Effect of cyclooxygenase-2 on vascular endothelial cell apoptosis induced by cigarette smoke extract].

OBJECTIVE: To explore the effect of cyclooxygenase-2 on vascular endothelial cell apoptosis induced by cigarette smoke extract. METHODS: Human vascular endothelial cells (ECV-304) were cultured in vitro, and those at the exponential growth phase were studied in experiments. The experiment was completed through 3 steps: (1) ECV-304 cells were cultured with 0.0%, 0.5%, 1.0% and 5.0% CSE for 12 h. (2) ECV-304 cells were exposed to 5.0% CSE for 0, 3, 6, 9, 12 and 24 h. (3) Endothelial cells were treated by 5% CSE, together with different concentrations of selective COX-2 inhibitor celecoxib (0.0, 2.5, 5.0, 10.0, 20.0, 50.0 micromol/L concentrations) for 9 h. The cell apoptosis rate was tested by Hoechst staining and flow cytometry methods, and the expression of COX-2 protein by immunocytochemistry and Western blotting. RESULTS: CSE induced ECV-304 cell apoptosis and COX-2 expression in a dose-dependent manner. The apoptosis rate of ECV-304 cells with 5.0% CSE was the highest (5.40+/-0.39)%. CSE- induced COX-2 expression reached the highest level with 5.0% CSE (206.1+/-15.5), the differences being significant (F=90.03, 159.94, all P<0.05). Furthermore CSE induced both apoptosis rate and COX-2 expression time-dependently, with the apoptosis rate achieving the peak after 24 h (8.87+/-0.41)%, while COX-2 expression reached the highest level at 9 h. The selective COX-2 inhibitor celecoxib inhibited COX-2 protein expression partially and augmented cell apoptosis induced by CSE. CONCLUSIONS: CSE induces endothelial cell apoptosis and increases the expression of COX-2 protein in vascular endothelial cells. Celecoxib, the selective COX-2 inhibitor, reduces the expression of COX-2 protein and promotes cell apoptosis induced by CSE in vascular endothelial cells. COX-2 may play an important role in protecting development of CSE-associated apoptosis of endothelial cells.

[Guiding significance of diaphragm function evaluation in ventilation weaning].

Diaphragm dysfunction is common in clinical work, which is a frequently important cause of ventilation weaning failure ignored by clinicians. Assessing diaphragmatic function while weaning helps early detection and prevention of weaning failure, so as to improve the clinical outcome of patients on mechanical ventilation (MV). Reviewing studies of diaphragmatic function evaluation in weaning, we can find that assessing diaphragmatic function during weaning can help guide weaning. Weaning predictors including pressure index, electrophysiological index and morphological index, among which bedside ultrasound as a morphological index is widely used in intensive care unit (ICU), which is simple, non-invasive, and easy to operate. It is also accurate in the assessment of diaphragmatic function and guidance on weaning, which is worthy of promotion and application.

The role of cyclooxygenase-2 in the protection against apoptosis in vascular endothelial cells induced by cigarette smoking.

BACKGROUND: Apoptosis has been demonstrated to be an important upstream event in the pathogenesis of chronic obstructive pulmonary disease (COPD). Cyclooxygenase-2 (COX-2) seems to be biologically relevant in COPD. However, the role of COX-2 in the apoptosis in vascular endothelial cells induced by cigarette smoke extract (CSE) remains to be elucidated. Our recent study found that the prostacyclin, one of the COX products in the microvascular endothelium, inhibited apoptosis in the emphysematous lungs of rats induced by CSE. In order to clarify the role of COX-2 in the apoptosis of vascular endothelial cells induced by CSE, we performed the present experiment to elucidate it. METHODS: Twenty surgical lung specimens were obtained from 6 patients with COPD, 7 smoking controls and seven nonsmoking controls. The apoptotic index (AI) and COX-2 protein expression were detected in lung tissues. To further investigate the effects of CSE on the apoptosis and COX-2 expression in a human vascular endothelial cell line, the apoptosis rate and COX-2 expression were examined in human umbilical vein endothelial cells (ECV304) under exposure to varied concentrations of CSE as well as under exposure to 5.0% CSE for varied durations. Repeatedly, the apoptosis rate and COX-2 expression in ECV304 cells under 5.0% CSE were examined after exposing to varied concentrations of celecoxib, a highly selective COX-2 inhibitor. RESULTS: Significantly increased AI and expression of COX-2 were found both in the lungs of patients with COPD and smoking controls compared with nonsmoking controls. The CSE induced apoptosis in ECV304 cells in means of both dose-dependent and time-dependent manners. The COX-2 was slightly expressed in the cells after exposing to 5% CSE for 3 and 6 h, and markedly expressed after the exposure time for 9 and 12 h, but vanished after 24 h of the exposure. Of interest, with the completely block of the COX-2 expression by celecoxib at 50.0 µmol/L, the apoptosis rate was markedly increased again in ECV304 cells under exposure to 5.0% CSE. CONCLUSIONS: Endothelial cell apoptosis and the expression of COX-2 protein were increased in both COPD patients and CSE-induced vascular endothelial cells. Of interest, it seems that the COX-2 probably had a protective role against the apoptosis in the vascular endothelial cells induced by cigarette smoking.

Tumstatin 185-191 increases the sensitivity of non-small cell lung carcinoma cells to cisplatin by blocking proliferation, promoting apoptosis and inhibiting Akt activation.

PURPOSE: This study aimed to investigate the synergistic anti-tumor effects of tumstatin 185-191 and cisplatin in non-small cell lung carcinoma cells (NSCLC) (A549 cells and cisplatin resistant A549/DDP cells), and the potential role of Akt signaling pathway was also explored. METHODS: A549 or A549/DDP cells were treated with Tum185-191 or Tum185-191 plus cisplatin. Cell viability was assessed by modified MTT assay. 50% inhibiting concentration (IC50) and reversing drug-resistance index (RI) of chemotherapeutics were determined by MTT assay. Cell apoptosis was measured by Hoechst 33258 staining and flow cytometry. The activation of Akt signaling pathway was evaluated by immunocytochemistry and Western blot assay. RESULTS: Tum185-191 inhibited the proliferation of A549 cells and A549/DDP cells. In the presence of Tum185-191 (20 and 40 µM), IC50 of cisplatin reduced significantly in A549 cells and A549/DDP cells. Combined use of tumstatin 185-191 and cisplatin exerted synergistic effects in promoting apoptosis. A549 and A549/DDP cells had a high expression of p-Akt, and Tum185-191, but not cisplatin, significantly inhibited p-Akt expression. Combined use of cisplatin and Tum185-191 failed to further inhibit p-Akt expression. After Tum185-191 treatment, the increased p-Akt expression was observed at 15 min, peaked at 30-60 min, but disappeared at 120 min. CONCLUSION: Tum185-191 increases the apoptosis, inhibit the proliferation, enhance the sensitivity of A549 cells to cisplatin and also partly reverse the resistance of A549-DDP cells to cisplatin, which is at least partially mediated by inactivating Akt pathway. These findings provide evidence for the chemotherapy of NSCLC with Tum185-191 and cisplatin.