[Effects of Rg_1 on LPS-induced apoptosis and autophagy of lung epithelial cells].

This paper aimed to study the protective effect of ginsenoside Rg_1 on endotoxin(LPS)-induced apoptosis of lung epithelial cells and its mechanism of action. Mouse lung epithelial cells(MLE-12) were first treated with LPS. The autophagy changes and apoptosis and the relationship with concentration and time of LPS were observed. Then,the level of autophagy in MLE-12 was regulated at a specific concentration and action time of LPS,and the changes of apoptosis were observed. Secondly,ginsenoside Rg_1 and autophagy inhibitor 3-MA were added respectively at the same concentration and action time of LPS. The lung epithelial cells were grouped to observe the effect of ginsenoside Rg_1 on LPS-induced apoptosis of lung epithelial cells and its mechanism. In the animal experiment,the mice were grouped and tested by apoptosis protein,lung injury score and HE staining section to verify whether ginsenoside Rg_1 has a protective effect on LPS-induced lung injury. The results showed that apoptosis and autophagy increased as the rise of concentration after treatment with LPS for 12 h. The apoptosis increased gradually,and the autophagy increased first and then decreased over time at the LPS concentration of 25 g·L-1. The apoptosis of LPS group was higher than that of control group,and LPS+3-MA group increased further,while apoptosis decreased significantly in LPS+RAM(rapamycin,autophagy promoter) group. The autophagy increased in LPS group,decreased in LPS+3-MA group and increased in LPS+RAM group. The apoptosis of LPS group was higher than that of control group,and the apoptosis of LPS+Rg_1 group decreased. The apoptosis of LPS+Rg_1+3-MA group increased again. The autophagy of LPS group further increased after administration of ginsenoside Rg_1,but decreased after administration of 3-MA. In the in vivo experiments in mice,the apoptosis of LPS group increased significantly compared with the control group,while LPS + ginsenoside Rg_1 group decreased. Lung injury score and HE staining also conformed to the above trend. LPS can induce the apoptosis of lung epithelial cells in a time-dependent and concentration-dependent manner. The autophagy of lung epithelial cells increases with the rise of LPS concentration. At the specific concentration of LPS,autophagy increases first and then decreases after 12-16 hours. Proper increase of autophagy in lung epithelial cells within a certain period of time can reduce the apoptosis induced by LPS,while inhibition of autophagy can increase apoptosis. Ginsenoside Rg_1 has a protective effect on lung cancer epithelial cell apoptosis induced by autophagy.

The preparation and dual-mode detection of ascorbic acid based on poly(N-isopropylacrylamide) nanogel with oxidase-like activity.

Nanozymes have recently become a research hotspot because of the advantages of good stability, excellent catalytic performance and easy storage in comparison to natural enzymes. Nanozymes with oxidase-like activity get special attention because they needn't the participation of hydrogen peroxide. In this paper, poly(N-isopropylacrylamide) nanogel with oxidase-like activity was synthesized for the first time. The catalytic mechanism was explored by EPR and UV spectroscopy after adding specific trapping agents of ROS, and the results showed that PNIPAM NG can catalyze O2 to 1O2. In the presence of PNIPAM NG, o-phenylenediamine (OPD) and ascorbic acid (AA) can be oxidized to 2,3-diaminophenazine (oxOPD) and dehydroascorbic acid (DHA), and DHA can further react with OPD to produce a fluorescence substance. The colorimetric and fluorescence detection platforms for AA were constructed based on the above principles. Both platforms have satisfactory results in real samples. The fluorescence platform has better sensitivity and selectivity than the colorimetric platform.

Arctigenin attenuates paraquat-induced human lung epithelial A549 cell injury by suppressing ROS/p38 mitogen-activated protein kinases-mediated apoptosis.

BACKGROUND: Paraquat (PQ)-induced acute lung injury (ALI) and pulmonary fibrosis are common diseases with high mortality but without effective antidotes in emergency medicine. Our previous study has proved that arctigenin suppressed pulmonary fibrosis induced by PQ. We wondered whether arctigenin could also have a protective effect on PQ-induced ALI. METHODS: A PQ-induced A549 cell injury model was used, and the effect of arctigenin was determined by a cell counting kit-8 (CCK-8) cell viability assay. In addition, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labelling (TUNEL) staining assays and mitochondrial membrane potential assays were performed to evaluate the level of cell apoptosis. The generation of reactive oxygen species (ROS) was reflected by dihydroethidium (DHE) staining and a 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) assay. Moreover, immunoblotting studies were used to assess the expression of mitogen-activated protein kinases (MAPKs) and p38 MAPK. RESULTS: Arctigenin attenuated PQ-induced inhibition of A549 cell viability in a dose-dependent manner. Arctigenin also significantly reduced PQ-induced A549 cell apoptosis, as reflected by the TUNEL assay and mitochondrial membrane potential assay, which may result from suppressed ROS/p38 MAPK signaling because we found that arctigenin dramatically suppressed ROS generation and p38 MAPK phosphorylation. CONCLUSION: Arctigenin could attenuate PQ-induced lung epithelial A549 cell injury in vitro by suppressing ROS/p38 MAPK-mediated cell apoptosis, and arctigenin might be considered a potential candidate drug for PQ-induced ALI.

Pravastatin attenuates sepsis-induced acute lung injury through decreasing pulmonary microvascular permeability via inhibition of Cav-1/eNOS pathway.

BACKGROUND: Disruption of alveolar endothelial barrier caused by inflammation drives the progression of septic acute lung injury (ALI). Pravastatin, an inhibitor of HMG Co-A reductase, has potent anti-inflammatory effects. In the present study, we aim to explore the beneficial role of pravastatin in sepsis-induced ALI and its related mechanisms. METHODS: A septic ALI model was established by cecal ligation and puncture (CLP) in mice. The pulmonary microvascular endothelial cells (PMVECs) were challenged with lipopolysaccharide (LPS). The pathological changes in lung tissues were examined by HE staining. The pulmonary microvascular permeability was determined by lung wet-to-dry (W/D) weight ratio and Evans blue staining. The total protein concentration in bronchoalveolar lavage fluid (BALF) was detected by BCA assay. The levels of TNF-α, IL-1ß, and IL-6 were assessed by qRT-PCR and ELISA. Apoptosis was determined by flow cytometry and TUNEL. Western blotting was performed for detection of target protein levels. The expression of VE-Cadherin in lung tissues was evaluated by immunohistochemical staining. RESULTS: Pravastatin improved survival rate, attenuated lung pathological changes and reduced pulmonary microvascular permeability in septic mice. In addition, pravastatin restrained sepsis-induced inflammatory response and apoptosis in the lung tissues and PMVECs. Moreover, pravastatin up-regulated the levels of junction proteins ZO-1, JAM-C, and VE-Cadherin. Finally, pravastatin suppressed inflammation, apoptosis and enhanced the expression of junction proteins via regulating Cav-1/eNOS signaling pathway in LPS-exposed PMVECs. CONCLUSION: Pravastatin ameliorates sepsis-induced ALI through improving alveolar endothelial barrier disruption via modulating Cav-1/eNOS pathway, which may be an effective candidate for treating septic ALI.

Pretreatment with intestinal trefoil factor alleviates stress-induced gastric mucosal damage via Akt signaling.

BACKGROUND: Stress-related gastric mucosal damage or ulcer remains an unsolved issue for critically ill patients. Stress ulcer prophylaxis has been part of routine intensive care, but uncertainty and controversy still exist. Co-secreted with mucins, intestinal trefoil factor (ITF) is reported to promote restitution and regeneration of intestinal mucosal epithelium, although the mechanism remains unknown. AIM: To elucidate the protective effects of ITF on gastric mucosa and explore the possible mechanisms. METHODS: We used a rat model of gastric mucosal damage induced by water immersion restraint stress and lipopolysaccharide-treated human gastric epithelial cell line to investigate the potential effects of ITF on damaged gastric mucosa both in vivo and in vitro. RESULTS: ITF promoted the proliferation and migration and inhibited necrosis of gastric mucosal epithelia in vitro. It also preserved the integrity of gastric mucosa by upregulating expressions of occludin and zonula occludens-1. In the rat model, pretreatment with ITF ameliorated the gastric mucosal epithelial damage and facilitated mucosal repair. The protective effects of ITF were confirmed to be exerted via activation of Akt signaling, and the specific inhibitor of Akt signaling LY249002 reversed the protective effects. CONCLUSION: ITF might be a promising candidate for prevention and treatment of stress-induced gastric mucosal damage, and further studies should be undertaken to verify its clinical feasibility.

Probable risk factors for postoperative delirium in patients undergoing spinal surgery.

Postoperative delirium and its risk factors had been widely reported in several kinds of surgeries; however, there is only one known article relative to postoperative delirium in spinal surgery. We retrospectively examined the incidence of postoperative delirium and the probable risk factors in patients undergoing spinal surgery in our hospital, with the same aged non-delirium patients as controls, over a 6-month period. Studies about postoperative delirium were reviewed and referenced for variable factors collecting in our study. T tests, chi(2) test and logistic regression analysis were performed to evaluate the various factors related to postoperative delirium. A total of 18 patients (3.3%), all of them were aged 54 years or older, had postoperative delirium after surgery. Patients without postoperative delirium aged 54 years or older served as the control group. The percentage of patients older than 65 years (P = 0.003), with comorbid diseases such as diabetes mellitus (P = 0.042) or central nervous system disorders (P = 0.013), with a surgical history (P = 0.028) in delirium group was larger than the control group. The absolute number of medications being taken before the operation in the delirium patients was also more than the control group (P = 0.000). The percentage of patients transfused with 800 mL or more blood was also larger (P = 0.024) in delirium group was larger than the control group. Logistic regression analysis showed that central nervous system disorder (OR 6.480), surgical history (OR 3.499), age older than 65 years (OR 3.390), diabetes mellitus (OR 2.981), transfused 800 mL or more blood (OR 2.537), and hemoglobin less than 100 g/L (OR 0.281) were significantly related to the occurrence postoperative delirium. Our findings suggest that postoperative delirium in spinal surgery can also occurred in younger patients and with an acceptable incidence in total. The risk for postoperative delirium is multifactorial. More prospective research is necessary in order to evaluate these and other risk factors in greater detail.