PLD2 deficiency alleviates endothelial glycocalyx degradation in LPS-induced ARDS/ALI.

- Acute respiratory distress syndrome (ARDS)/acute lung injury (ALI) is a life-threatening condition marked by severe lung inflammation and increased lung endothelial barrier permeability. Endothelial glycocalyx deterioration is the primary factor of vascular permeability changes in ARDS/ALI. Although previous studies have shown that phospholipase D2 (PLD2) is closely related to the onset and progression of ARDS/ALI, its role and mechanism in the damage of endothelial cell glycocalyx remains unclear. We used LPS-induced ARDS/ALI mice (in vivo) and LPS-stimulated injury models of EA.hy926 endothelial cells (in vitro). We employed C57BL/6 mice, including wild-type and PLD2 knockout (PLD2-/-) mice, to establish the ARDS/ALI model. We applied immunofluorescence and ELISA to examine changes in syndecan-1 (SDC-1), matrix metalloproteinase-9 (MMP9), inflammatory cytokines (TNF-α, IL-6, and IL-1ß) levels and the effect of external factors, such as phosphatidic acid (PA), 1-butanol (a PLD inhibitor), on SDC-1 and MMP9 expression levels. We found that PLD2 deficiency inhibits SDC-1 degradation and MMP9 expression in LPS-induced ARDS/ALI. Externally added PA decreases SDC-1 levels and increases MMP9 in endothelial cells, hence underlining PA's role in SDC-1 degradation. Additionally, PLD2 deficiency decreases the production of inflammatory cytokines (TNF-α, IL-6, and IL-1ß) in LPS-induced ARDS/ALI. In summary, these findings suggest that PLD2 deficiency plays a role in inhibiting the inflammatory process and protecting against endothelial glycocalyx injury in LPS-induced ARDS/ALI.

Insomnia among coronavirus disease 2019 survivors: A single-center cross-sectional study.

Since the coronavirus disease 2019 (COVID-19) epidemic, insomnia has become one of the longer COVID-19 symptoms. This study aimed to investigate insomnia among COVID-19 survivors and explore the occurrence and influencing factors of insomnia. A cross-sectional study was performed from December 2022 to February 2023 through an online questionnaire star survey with 8 questions. The insomnia severity index scale (ISI) was used to assess the severity of insomnia. Univariate analysis was used to analyze the factors related to COVID-19 infection. A total of 564 participants (183 males and 381 females) were surveyed in the present study. The prevalence of insomnia was 63.12%. Among these insomnia patients, there were 202 (35.82%) with sub-threshold symptoms, 116 (20.57%) with moderate symptoms, and 38 (6.74%) with severe symptoms. Univariate analysis indicated that there were statistically significant differences in the prevalence of insomnia among COVID-19 survivors of different ages, occupations, and educational levels (P < .05). Of the 356 insomnia patients, 185 (51.97%) did not take any measures against insomnia, while those who took drugs only, physical exercise only, drugs and physical exercise, and other measures were 90 (25.28%), 42 (11.80%), 17 (4.78%), and 22 (6.18%), respectively. Additionally, of the 107 insomnia patients with drug therapy, 17 (15.89%) took estazolam, 16 (14.95%) took alprazolam, 39 (36.45%) took zopiclone, and 35 (32.71%) took other drugs to improve insomnia symptoms. The prevalence of insomnia symptoms remains high among COVID-19 survivors in China. Education level and occupation may be the influencing factors. Unfortunately, most patients with insomnia do not take corresponding treatment measures.

[Effect of continuous blood purification on immunity and endothelial cell function in patients with sepsis].

OBJECTIVE: To explore the effect of continuous blood purification (CBP) on the immunity and endothelial cell function of patients with sepsis. METHODS: A prospective study was conducted. The patients aged ≥ 18 years old and meeting the diagnostic criteria of sepsis admitted to the department of critical care medicine of Binzhou Medical University Hospital from March 2019 to October 2020 were selected as the research subjects, and the patients were divided into standard treatment group and CBP treatment group according to random number table method. Both groups were given standard treatment including initial fluid resuscitation, infection source control and antibiotics according to the 2016 international guidelines for the management of sepsis and septic shock. CBP treatment group was additionally given continuous veno-venous hemofiltration (CVVH) at a dose of 25-30 mL×kg-1×h-1 and blood flow rate of 150-200 mL/min for more than 20 hours a day for 3 days. The clinical data of patients including blood lactic acid (Lac), procalcitonin (PCT), lymphocyte count (LYM), acute physiology and chronic health evaluation II (APACHE II) score, sequential organ failure assessment (SOFA) score were recorded before treatment and 1 day and 3 days after treatment. At the same time, the venous blood was collected, and the immune function related indexes [interleukins (IL-4, IL-7), programmed death receptor-1 (PD-1), programmed death ligand-1 (PD-L1), interferon-γ (IFN-γ)] and endothelial cell injury related markers [soluble thrombomodulin (sTM), angiopoietin-2 (Ang-2), von Willebrand factor (vWF), heparan sulfate (HS), syndecan-1 (SDC-1)] levels in serum were determined by enzyme-linked immunosorbent assay (ELISA). The length of intensive care unit (ICU) stay of patients in the two groups was recorded, and the outcomes of patients in the two groups were followed up for 28 days. RESULTS: Finally, 20 patients were enrolled in the standard treatment group, and 19 patients were enrolled in the CBP treatment group. There were no significant differences in gender, age and infection site between the two groups. The length of ICU stay in the standard treatment group was (10±5) days, and 5 patients died and 15 patients survived after 28 days. The length of ICU stay in the CBP treatment group was (9±4) days, and 8 patients died and 11 patients survived after 28 days. There were no significant differences in the length of ICU stay and number of patients who died within 28 days between the two groups (both P > 0.05). There were no significant differences in the Lac, PCT, LYM, APACHE II score, SOFA score and immune function and endothelial cell injury related indexes before treatment and 1 day after treatment between the two groups. After 3 days of treatment, the Lac, PCT, APACHE II score and SOFA score of the CBP treatment group were significantly lower than those before treatment, and pro-inflammatory and anti-inflammatory cytokines such as IFN-γ and IL-4, apoptosis-related indicators such as PD-1 and IL-7, and endothelial injury related factors such as sTM, SDC-1 and HS were significantly improved compared with the pre-treatment, the improvement degree of the above indicators was more obvious than that of the standard treatment group, and LYM was significantly higher than that of the standard treatment group (×109/L: 1.3±0.3 vs. 0.9±0.4, P < 0.05), IL-4, IFN-γ, IFN-γ/IL-4 ratio, IL-7, PD-1, sTM, SDC-1, HS, and Ang-2 were significantly lower than those of the standard treatment group [IL-4 (ng/L): 2.8 (1.5, 3.2) vs. 3.3 (2.7, 5.2), IFN-γ (ng/L): 6.3 (5.4, 106.5) vs. 217.9 (71.4, 517.1), IFN-γ/IL-4 ratio: 3.7 (1.8, 70.3) vs. 59.1 (18.3, 124.9), IL-7 (ng/L): 4.6 (3.2, 5.1) vs. 6.3 (5.2, 8.0), PD-1 (µg/L): 0.04 (0.03, 0.06) vs. 0.08 (0.05, 0.12), sTM (µg/L): 4.9 (4.3, 7.4) vs. 8.7 (6.0, 10.8), SDC-1 (µg/L): 0.6 (0.3, 1.1) vs. 0.9 (0.8, 2.5), HS (ng/L): 434.8 (256.2, 805.0) vs. 887.9 (620.1, 957.3), Ang-2 (ng/L): 934.0 (673.3, 1 502.1) vs. 2 233.9 (1 472.5, 3 808.4)], the differences were statistically significant (all P < 0.05). CONCLUSIONS: CBP treatment can eliminate the patient's immunosuppressive state, reduce a variety of endothelial injury markers and the degradation of glycocalyx, but cannot decrease the 28-day death risk or shorten the length of ICU stay.

[Prognostic value of PCSK9 and blood lipid in patients with sepsis].

OBJECTIVE: To investigate the prognostic value of proprotein convertase subtilisin/kexin type 9 (PCSK9) and blood lipid indexes in patients with sepsis. METHODS: Patients with sepsis or septic shock who were ≥ 18 years old and met the Sepsis-3.0 diagnostic criteria admitted to the department of critical care medicine of Binzhou Medical University Hospital from January to October 2021 were enrolled. Healthy adults at the same period were selected as healthy control group. Baseline characteristics, acute physiology and chronic health evaluation II (APACHE II) and sequential organ failure assessment (SOFA) score were recorded. Venous blood samples were collected within 24 hours after diagnosis, and serum PCSK9 was determined by enzyme-linked immunosorbent assay (ELISA) at 1, 3 days and 5 days. Meanwhile, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglyceride (TG) and lipoprotein A were detected. The differences of each index between sepsis group (28-day death group and survival group) and healthy control group were compared. Meanwhile, the indexes of patients with different severity and 28-day prognosis in sepsis group were compared. Receiver operator characteristic curve (ROC curve) was drawn to evaluate the predictive value of PCSK9 and blood lipid for the prognosis of sepsis. Multivariate Logistic regression was used to analyze the influencing factors for the prognosis of sepsis, and the Kaplan-Meier survival curve at 28th day was drawn. RESULTS: There were 50 patients in sepsis group (including 19 patients with sepsis, 31 patients with septic shock) and 27 patients in healthy control group. In the sepsis group, 19 patients died and 31 patients survived within 28 days. The serum PCSK9 in the sepsis group was significantly higher than that in the healthy control group [µg/L: 223.09 (198.47, 250.82) vs. 188.00 (165.27, 214.90), P < 0.01], and HDL-C, LDL-C, TC and lipoprotein A were significantly lower than those in the healthy control group [HDL-C (mmol/L): 0.82±0.35 vs. 1.45±0.24, LDL-C (mmol/L): 1.53 (1.14, 2.47) vs. 2.89 (2.55, 3.19), TC (mmol/L): 2.03 (1.39, 2.84) vs. 4.24 (3.90, 4.71), lipoprotein A (g/L): 8.80 (5.66, 17.56) vs. 27.03 (14.79, 27.03), all P < 0.01]. PCSK9 in the sepsis death group was higher than that in the survival group [µg/L: 249.58 (214.90, 315.77) vs. 207.01 (181.50, 244.95), P < 0.01], and the HDL-C, LDL-C and TC were lower than those in the survival group [HDL-C (mmol/L): 0.64±0.35 vs. 0.93±0.30, LDL-C (mmol/L): 1.32±0.64 vs. 2.08±0.94, TC (mmol/L): 1.39 (1.01, 2.23) vs. 2.69 (1.72, 3.81), all P < 0.01]. With the progression of the disease, the PCSK9 in the sepsis death group and the survival group was significantly lower than that within 1 day of diagnosis (all P < 0.05). ROC curve analysis showed that PCSK9 had higher predictive value of 28-day death than HDL-C, LDL-C, TC [area under ROC curve (AUC) and 95% confidence interval (95%CI): 0.748 (0.611-0.885) vs. 0.710 (0.552-0.868), 0.721 (0.575-0.867), 0.702 (0.550-0.854)]. Multivariate Logistic regression analysis showed that PCSK9 was an independent risk factor affecting the 28-day prognosis of sepsis (ß value was 1.014, P = 0.020). Kaplan-Meier survival curve analysis showed that when PCSK9 ≥ 208.97 µg/L, with the increase of PCSK9, the 28-day survival rate of sepsis patients decreased significantly. CONCLUSIONS: PCSK9, HDL-C, LDL-C and TC can all predict the 28-day prognosis of patients with sepsis. The prognostic value of PCSK9 is the highest. PCSK9 is an independent risk factor affecting the prognosis of sepsis. In the early stage of the disease, PCSK9 may have a good predictive value for the prognosis of sepsis. When PCSK9 ≥ 208.97 µg/L, the 28-day survival rate decreased significantly.

Association between plasma glycocalyx component levels and poor prognosis in severe influenza type A (H1N1).

Influenza A virus infection causes a series of diseases, but the factors associated with disease severity are not fully understood. Disruption of the endothelial glycocalyx contributes to acute lung injury in sepsis, but has not been well studied in H1N1 influenza. We aim to determine whether the plasma glycocalyx components levels are predictive of disease severity in H1N1 influenza. This prospective observational study included 53 patients with influenza A (H1N1) during the influenza season, and 30 healthy controls in our hospital. Patients were grouped by severity and survival. We collected clinical data and blood samples at admission. Inflammatory factors (tumor necrosis factor-α, interleukin-6, interleukin-10) and endothelial glycocalyx components (syndecan-1, hyaluronan, heparan sulfate) were measured. The plasma levels of syndecan-1, hyaluronan, and heparan sulfate were significantly higher in patients with severe influenza A (H1N1) than in mild cases. Syndecan-1 and hyaluronan were positively correlated with disease severity, which was indicated by the APACHE II and SOFA scores and lactate levels, and negatively correlated with albumin levels. At a cutoff point ≥ 173.9 ng/mL, syndecan-1 had a 81.3% sensitivity and 70.3% specificity for predicting of 28-day mortality. Kaplan-Meier analysis demonstrated a strong association between syndecan-1 levels and 28-day mortality (log-rank 11.04, P = 0.001). Elevated plasma levels of syndecan-1 has a potential role in systemic organ dysfunction and may be indicative of disease severity in patients with influenza A (H1N1).

Sleep and circadian rhythm disturbances in intensive care unit (ICU)-acquired delirium: a case-control study.

OBJECTIVE: The relationships among sleep, circadian rhythm, and intensive care unit (ICU)-acquired delirium are complex and remain unclear. This study aimed to examine the pathophysiological mechanisms of sleep and circadian rhythm disturbances in patients with ICU-acquired delirium. METHODS: This study included critical adult patients aged 18 to 75 years who were treated in the ICU. Twenty-four-hour polysomnography was performed and serum melatonin and cortisol levels were measured six times during polysomnography. Receiver operating characteristic curves and binomial logistic regression were used to evaluate the potential of sleep, melatonin, and cortisol as indicators of delirium in the ICU. RESULTS: Patients with delirium (n = 24) showed less rapid eye movement (REM) sleep compared with patients without delirium (n = 24, controls). Melatonin levels were lower and cortisol levels were higher in the delirium group than in the control group. REM sleep, melatonin, and cortisol were significantly associated with delirium. The optimal cutoff values of REM sleep and mean melatonin and cortisol levels that predicted delirium were ≤1.05%, ≤422.09 pg/mL, and ≥212.14 ng/mL, respectively. CONCLUSIONS: REM sleep, and melatonin and cortisol levels are significantly associated with the risk of ICU-acquired delirium. Improved sleep and readjustment of circadian rhythmicity may be therapeutic targets of ICU-acquired delirium.

[Significance of high mobility group box 1, von Willebrand factor and other cytokines in the evaluation of severity and prognosis of sepsis patients].

OBJECTIVE: To explore the value of high mobility group box 1 (HMGB1), von Willebrand factor (vWF) and other cytokines in predicting the severity and prognosis of sepsis patients. METHODS: Patients with sepsis and septic shock who ≥ 18 years old and met the Sepsis-3 diagnostic criteria admitted to the department of critical care medicine of Binzhou Medical University Hospital from January to June 2019 were taken as the research objects. The healthy individuals for regular health examination in the same period were taken as the control. The basic information, acute physiology and chronic health evaluation II (APACHE II) and sequential organ failure assessment (SOFA) scores were recorded. The venous blood was taken within 24 hours after the patients were diagnosed. The levels of HMGB1, vWF, tumour necrosis factor-α (TNF-α), interleukin-10 (IL-10), soluble thrombomodulin (sTM), vascular endothelial growth factor receptor 2 (VEGFR-2), angiopoetin-2 (Ang-2) and other cytokines in serum were determined by enzyme linked immunosorbent assay (ELISA). Differences among patients with sepsis, septic shock, healthy physical examinees, and patients who died in 28-day and those who survived, were compared. Spearman rank correlation method was used to analyze the correlation among each cytokine and APACHE II, SOFA scores. The receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of cytokines on the prognosis of patients with sepsis/septic shock. Logistic regression was used to analyze the risk factors of 28-day death. RESULTS: Eleven patients with sepsis, 25 patients with septic shock and 30 healthy individuals were enrolled. Among the patients with sepsis/septic shock, 15 died in 28-day and 21 survived. The serum levels of TNF-α, IL-10, HMGB1, vWF, sTM and VEGFR-2 in patients with sepsis were significantly higher than those in the healthy control group. The levels of TNF-α, IL-10, HMGB1, vWF, sTM in septic shock group were higher than those in the sepsis group, while the Ang-2 level decreased significantly. The serum levels of TNF-α, IL-10, HMGB1, vWF and sTM in the death group were higher than those in the survival group, while Ang-2 was lower than the survival group. Spearman correlation analysis showed that HMGB1, TNF-α, sTM, IL-10, vWF were positively correlated with APACHE II score when patients with sepsis/septic shock were enrolled (r values were 0.652, 0.666, 0.445, 0.430 and 0.355, respectively, all P < 0.05), and HMGB1, TNF-α also positively correlated with SOFA score (r values were 0.433, 0.479, both P < 0.05). Ang-2 was negatively correlated with APACHE II and SOFA scores (r values were -0.519, -0.440, both P < 0.05). ROC curve analysis showed that the predictive value of HMGB1, vWF, IL-10, sTM for 28-day death in patients with sepsis/septic shock were higher than the APACHE II score [the area under ROC curve (AUC) and 95% confidence interval (95%CI): 0.946 (0.870-1.000), 0.902 (0.790-1.000), 0.877 (0.745-1.000), 0.868 (0.734-1.000) vs. 0.846 (0.700-0.991)]. Logistic regression analysis showed that APACHE II score, vWF, sTM, and IL-10 were independent risk factors for 28-day death in patients with sepsis/septic shock (ß values were 4.731, 0.407, -7.058, -0.887, all P < 0.05). CONCLUSIONS: HMGB1, vWF, IL-10, sTM and other cytokines all can be used to evaluate the severity and prognosis of sepsis patients.

[Prognostic analysis of severe patients with bloodstream infection caused by Enterobacteriaceae bacteria].

OBJECTIVE: To investigate the prognostic factors of severe patients with bloodstream infection (BSI) caused by Enterobacteriaceae bacteria. METHODS: Patients suffered from BSI caused by Enterobacteriaceae bacteria admitted to department of critical care medicine of Binzhou Medical University Hospital from October 2016 to October 2019 were enrolled. The information of gender, age, combined shock, acute physiology and chronic health evaluation II (APACHE II), sequential organ failure assessment (SOFA), sensitivity of initial antibiotics, as well as the baseline of procalcitonin (PCT), white blood cell count (WBC), platelet (PLT), albumin (ALB) were collected. The 72-hour PCT clearance rate (72 h PCTc) was calculated after 72 hours' treatment. According to the clinical outcome after 28 days, the patients were divided into recovery group and death group. The differences of clinical indicators between the two groups were compared, and then the statistical significant variables were further performed by Logistic regression to analyze the factors affecting the prognosis of patients. The receiver operating characteristic (ROC) curve was drawn to evaluate the predictive efficacy of the factors in severe BSI. RESULTS: A total of 86 patients were enrolled, among whom 54 cases recovered while 32 cases died, and the 28-day mortality was 37.2%. There was no significant difference in gender, age, sensitivity of initial antibiotics, baseline levels of PCT and WBC between two groups. In the death group, the shock incidence, APACHE II score, SOFA score were significantly higher than those in recovery group [shock incidence: 84.4% (27/32) vs. 46.3% (25/54), APACHE II: 24.94±7.65 vs. 17.02±6.57, SOFA: 11.00±3.27 vs. 6.30±2.65, all P < 0.01]; the PLT and ALB baseline levels, 72 h PCTc were significantly lower than those in recovery group [PLT (×109/L): 73.38±49.15 vs. 138.69±101.80, ALB (g/L): 25.47±5.91 vs. 28.59±4.53, 72 h PCTc: -44 (-170, 27)% vs. 63 (40, 77)%, all P < 0.01]. The above 6 variables were included in Logistic regression. The results showed that SOFA score was a risk factor for death in these patients [odds ratio (OR) = 1.930, P = 0.037], while 72 h PCTc and ALB were protective factors (OR values were 0.043, 0.783, P values were 0.008, 0.047). The SOFA, 72 h PCTc and ALB can be used to predict the prognosis of severe BSI, and the diagnostic value of the combination of three factors was the largest [area under the ROC curve (AUC) = 0.953, 95% confidence interval (95%CI) was 0.909-0.997], the sensitivity was 100%, and the specificity was 79.6%. CONCLUSIONS: Severe patients with BSI caused by Enterobacteriaceae bacteria had a high mortality. Higher SOFA score, and lower ALB and 72 h PCTc predicted the adverse outcome. The combination of the three factors has the greatest prognostic efficacy.

Both UFH and NAH alleviate shedding of endothelial glycocalyx and coagulopathy in LPS-induced sepsis.

Sepsis commonly progresses to disseminated intravascular coagulation and induces the activation of heparanase (HPA) and the shedding of endothelial glycocalyx constituents, including syndecan-1 (SDC-1) and heparan sulphate (HS). However, the degradation of glycocalyx and its association with coagulation disorders remains undetermined. The present study aimed to evaluate the effect of unfractionated heparin (UFH) and N-acetylheparin (NAH), which is a non-anticoagulant heparin derivative, on endothelial glycocalyx and coagulation function in a lipopolysaccharide (LPS)-induced sepsis rat model, and to compare the differences observed in coagulation function between UFH and NAH. Experimental rats were randomly assigned to four groups: Control; LPS; UFH + LPS; and NAH + LPS. Rats were administered UFH or NAH and subsequently, ~1 min later, administered LPS (10 mg/kg; intravenous). The blood and lung tissues of rats were collected 0.5, 2 and 6 h after LPS injection, and were used for subsequent analysis. The results demonstrated that HPA activity and SDC-1 and HS levels increased, and this increase was associated with inflammatory cytokines and coagulation/fibrinolysis markers in the sepsis rat model. Histopathological examination was performed, and the lung injury score and lung wet/dry ratio indicated that UFH and NAH also significantly improved lung tissue injury. The results of the ELISA analysis demonstrated that UFH and NAH treatment: i) significantly decreased the levels of inflammatory cytokines including tumor necrosis factor-α and interleukin-6; ii) inhibited HPA activity and protected the integrity of the glycocalyx, which was identified by decreased HS and SDC-1 levels; and iii) decreased the levels of prothrombin fragment 1+2, thrombin-antithrombin complex, and plasminogen activator inhibitor-1 and increased the levels of fibrinogen and antithrombin-III. Preconditioning with UFH decreased the plasma activated partial thromboplastin time. These results indicated that UFH and NAH may alleviate sepsis-induced coagulopathy, and this effect may have been due to an inhibition of HPA activity and decrease in the shedding of the endothelial glycocalyx.

Decitabine and 5-azacitidine both alleviate LPS induced ARDS through anti-inflammatory/antioxidant activity and protection of glycocalyx and inhibition of MAPK pathways in mice.

Decitabine (5-aza-2'-deoxycytidine, DAC) and 5-azacitidine (Aza), an inhibitor of DNA methyltransferases, possess a wide range of anti-metabolic and anti-cancer activities. This study examined the effects of DAC and Aza on inflammatory and oxidative injuries, as well as on glycocalyx and MAPK signaling pathways, in a LPS-stimulated ARDS mouse model. Results of ELISA revealed that DAC and Aza significantly inhibited the production of TNF-α and IL-1ß and prevented LPS-induced elevation of myeloperoxidase and malondialdehyde levels in serum. The W/D ratio of lung and histopathologic examination with hematoxylin and eosin staining showed that DAC and Aza pretreatment substantially improved lung tissue injury. DAC and Aza reduced the level of glycocalyx degradation products (e.g., heparan sulfate and haluronic acid) and protected glycocalyx integrity. Western blot assay demonstrated that DAC and Aza both significantly suppressed LPS-induced activation of the MAPK signaling pathways by blocking the phosphorylation of JNK, ERK and P38 in lung tissues. Bisulfite sequencing PCR and real time-PCR showed that DAC reversed the RASSF1A promoter hypermethylation and furthermore elevated the expression of RASSF1A, which is a tumor suppressor that regulates MAPK signaling pathway. These results suggested that DAC inhibited the MAPK signaling pathway in LPS-induced ARDS mice might via demethylation in RASSF1A promoter region and by restoring its expression. This study highlighted the close relationship between DNA methylation and the development and progression of ARDS.

Ulinastatin attenuates pulmonary endothelial glycocalyx damage and inhibits endothelial heparanase activity in LPS-induced ARDS.

Acute respiratory distress syndrome (ARDS) is a syndrome of acute respiratory failure characterized by major pathologic mechanisms of increased microvascular permeability and inflammation. The glycocalyx lines on the endothelial surface, which determines the vascular permeability, and heparanase play pivotal roles in the degradation of heparan sulfate (HS). HS is the major component of the glycocalyx. The aim of this study is to examine the effects of Ulinastatin (UTI) on vascular permeability and pulmonary endothelial glycocalyx dysfunction induced by lipopolysaccharide (LPS). In our study, C57BL/6 mice and human umbilical vein endothelial cells were stimulated with LPS to induce injury models. After 6 h of LPS stimulation, pulmonary pathological changes, pulmonary edema, and vascular permeability were notably attenuated by UTI. UTI inhibited LPS-induced endothelial glycocalyx destruction and significantly decreased the production of HS as determined by ELISA and immunofluorescence. UTI also reduced the active form of heparanase (50 kDa) expression and heparanase activity. Moreover, lysosome pH was investigated because heparanase (65 kDa) can be reduced easily in its active form at 50 kDa in a low pH environment within lysosome. Results showed that UTI could inhibit LPS-induced pH elevation in lysosome. In conclusion, UTI protects pulmonary endothelial glycocalyx integrity and inhibits heparanase activity during LPS-induced ARDS.

Astilbin alleviates LPS-induced ARDS by suppressing MAPK signaling pathway and protecting pulmonary endothelial glycocalyx.

Acute respiratory distress syndrome (ARDS) is a devastating disorder that is characterized by increased vascular endothelial permeability and inflammation. Unfortunately, no effective treatment beyond supportive care is available for ARDS. Astilbin, a flavonoid compound isolated from Rhizoma Smilacis Glabrae, has been used for anti-hepatic, anti-arthritic, and anti-renal injury treatments. This study examined the effects of Astilbin on pulmonary inflammatory activation and endothelial cell barrier dysfunction caused by Gram-negative bacterial endotoxin lipopolysaccharide (LPS). Endothelial cells from human umbilical veins or male Kunming mice were pretreated with Astilbin 24h before LPS stimulation. Results showed that Astilbin significantly attenuated the pulmonary histopathological changes and neutrophil infiltration 6h after the LPS challenge. Astilbin suppressed the activities of myeloperoxidase and malondialdehyde, as well as the expression of tumor necrosis factor-α and interleukin-6 in vivo and in vitro. As indices of pulmonary edema, lung wet-to-dry weight ratios, were markedly decreased by Astilbin pretreatment. Western blot analysis also showed that Astilbin inhibited LPS-induced activation of mitogen-activated protein kinase (MAPK) pathways in lung tissues. Furthermore, Astilbin significantly inhibited the activity of heparanase and reduced the production of heparan sulfate in the blood serum as determined by ELISA. These findings indicated that Astilbin can alleviate LPS-induced ARDS, which potentially contributed to the suppression of MAPK pathway activation and the degradation of endothelial glycocalyx.

Short communication: Camel milk ameliorates inflammatory responses and oxidative stress and downregulates mitogen-activated protein kinase signaling pathways in lipopolysaccharide-induced acute respiratory distress syndrome in rats.

Acute respiratory distress syndrome (ARDS) is a complex syndrome disorder with high mortality rate. Camel milk (CM) contains antiinflammatory and antioxidant properties and protects against numerous diseases. This study aimed to demonstrate the function of CM in lipopolysaccharide (LPS)-induced ARDS in rats. Camel milk reduced the lung wet:dry weight ratio and significantly reduced LPS-induced increases in neutrophil infiltration, interstitial and intra-alveolar edema, thickness of the alveolar wall, and lung injury scores of lung tissues. It also had antiinflammatory and antioxidant effects on LPS-induced ARDS. After LPS stimulation, the levels of proinflammatory cytokines (tumor necrosis factor-α, IL-10, and IL-1ß) in serum and oxidative stress markers (malondialdehyde, myeloperoxidase, and total antioxidant capacity) in lung tissue were notably attenuated by CM. Camel milk also downregulated mitogen-activated protein kinase signaling pathways. Given these results, CM is a potential complementary food for ARDS treatment.

Cyanidin-3-O-Glucoside Ameliorates Lipopolysaccharide-Induced Injury Both In Vivo and In Vitro Suppression of NF-κB and MAPK Pathways.

Cyanidin-3-O-glucoside (C3G), an anthocyanin belonging to the flavonoid family and commonly present in food and vegetables in human diet, has exhibited anti-inflammatory and anti-oxidant effects. This study aimed to investigate the protective ability of C3G against inflammatory and oxidative injuries, as well as to clarify the possible mechanism in lipopolysaccharide (LPS)-stimulated human umbilical vein endothelial cells (HUVECs) in vitro and acute respiratory distress syndrome mouse model in vivo. HUVECs or male Kunming mice were pretreated with C3G 1 h before LPS stimulation. C3G significantly inhibited the production of pro-inflammatory cytokines (tumor necrosis factor-α, interleukin (IL) -6, and IL-1ß) in cell supernatants and bronchoalveolar lavage fluid (BALF) as determined by enzyme-linked immunosorbent assay. Histopathologic examination with hematoxylin and eosinstaining showed that C3G pretreatment substantially suppressed inflammatory cell infiltration, alveolar wall thickening, and interstitial edemain lung tissues. C3G markedly prevented LPS-induced elevation of malondialdehyde and myeloperoxidase levels in lung tissue homogenates, wet to dry ratio of lung tissues, total cells, and inflammatory cells (neutrophils and macrophages) in BALF. Moreover, C3G reduced superoxide dismutase activity in the lung tissue homogenates. Western blot assay also showed that C3G pretreatment significantly suppressed LPS-induced activation of nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways by blocking the phosphorylation of inhibitor κB-α, NF-κB/P65, extracellular signal-regulated kinase, p38, and c-Jun NH2-terminal kinase in the lung tissues. In summary, C3G may ameliorate LPS-induced injury, which results from inflammation and oxidation, by inhibiting NF-κB and MAPK pathways and playing important anti-inflammatory and anti-oxidative roles.