[Clinical metabolomics of Zicuiyin in treatment of diabetic kidney disease].

This study aimed to analyze the therapeutic effect of Zicuiyin on diabetic kidney disease(DKD) and explore the possible targets of this formula. Eighteen DKD patients treated in the endocrine department or nephrology department of Second Affilia-ted Hospital of Tianjin University of Traditional Chinese Medicine from January to December in 2019 were enrolled and assigned into a test group(n=10) and a control group(n=8). Both groups received routine chemical medicine treatment. In addition, the test group was treated with Zicuiyin and the control group with Huangkui Capsules for 8 weeks. The clinical trial was approved by the Ethics Committee of Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine, with the ethical approval No. 2017-023-01, and all the patients signed the informed consent form. The results showed that the 8-week treatment with Zicuiyin lowered the level of glycosylated hemoglobin(HbA1c) and recovered the 24 h urinary protein(24hUP), 24 h urinary microalbumin(24hmAlb), urine albumin-to-creatinine ratio(UACR), and estimated glomerular filtration rate(eGFR) of the patients with 24hUP<3.5 g. According to the different levels in 24hUP, all the patients were divided into two subgroups(subgroup A with 24hUP<3.5 g and subgroup B with 24hUP≥3.5 g). The ultra-high performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS)-based non-targeted metabolomics analysis was conducted on the baseline serum samples from diffe-rent subgroups of patients. Nineteen biomarker candidates were identified to distinguish the metabolic differences between the two subgroups, and their correlations with clinical indicators were analyzed. Zicuiyin lowered the levels of phenylalanine, pseudouridine, and adenosine [fold change(FC)<0.5, P<0.05] in subgroup A. The results indicated that Zicuiyin was more effective on the DKD patients with low urinary protein levels, and its targets were involved in phenylalanine metabolism and nucleoside metabolism.

Divergent Synthesis of Solanidine and 22-epi-Solanidine.

A divergent synthesis of solanidine and 22-epi-solanidine, two 25S natural steroidal alkaloids, from 25R-configured diosgenin acetate, is described. Initially, solanidine was synthesized through a series of transformations including a cascade ring-switching process of furostan-26-acid, an epimerization of C25 controlled by the conformation of six-membered lactone ring, an intramolecular Schmidt reaction, and an imine reduction/intramolecular aminolysis process. To address the epimerization issue during Schmidt reaction, an improved synthesis was developed, which also led to a synthesis of 22-epi-solanidine. In this synthesis, selective transformation of azido lactone to azido diol and amino diol was realized through a reduction relay tactic. The azido diol was transformed to solanidine via an intramolecular Schmidt reaction/N-alkylation/reduction process and to 22-epi-solanidine via an intramolecular double N-alkylation process.

Facial intramuscular lipoma occurrence following topical cosmetic injection with a mixture of basic fibroblast growth factor: A report of two cases.

Growth factors and cytokines control cell growth, proliferation and differentiation via a network of inter- and intracellular signalling pathways, and are involved in skin self-renewing and wound healing. In recent years, topical and injectable growth factors and cytokines have emerged as an intriguing therapeutic modality that can be harnessed for aesthetic purposes. However, very little data are available on their long-term safety and tolerability. In this report, we describe two cases of patients, who developed intramuscular lipoma of the chin following topical injection with a mixture of basic fibroblast growth factor as the main ingredients for chin augmentation. Biopsies in the two cases were performed at our department, and revealed intramuscular lipoma. Our report indicates that the topical injection of growth factors can lead to tumorigenesis, so health care providers need to be aware of its potential consequences.

[Research on characteristics of soil clay mineral evolution in paddy field and dry land by XRD spectrum].

The present paper took the typical saline-alkali soil in Jilin province as study object, and determinated the soil clay mineral composition characteristics of soil in paddy field and dry land. Then XRD spectrum was used to analyze the evolutionary mechanism of clay mineral in the two kinds of soil. The results showed that the physical and chemical properties of soil in paddy field were better than those in dry land, and paddy field would promote the weathering of mineral particles in saline-alkali soil and enhance the silt content. Paddy field soil showed a strong potassium-removal process, with a higher degree of clay mineral hydration and lower degree of illite crystallinity. Analysis of XRD spectrum showed that the clay mineral composition was similar in two kinds of soil, while the intensity and position of diffraction peak showed difference. The evolution process of clay mineral in dry land was S/I mixture-->vermiculite, while in paddy field it was S/I mixture-->vermiculite-->kaolinite. One kind of hydroxylated 'chlorite' mineral would appear in saline-alkali soil in long-term cultivated paddy field. Taking into account that the physical and chemical properties of soil in paddy field were better then those in dry land, we could know that paddy field could help much improve soil structure, cultivate high-fertility soil and improve saline-alkali soil. This paper used XRD spectrum to determine the characteristics of clay minerals comprehensively, and analyzed two'kinds of land use comparatively, and was a new perspective of soil minerals study.

[Analysis of XRD spectral characteristics of soil clay mineral in two typical cultivated soils].

The present paper took black soil and chernozem, the typical cultivated soil in major grain producing area of Northeast, as the study object, and determinated the soil particle composition characteristics of two cultivated soils under the same climate and location. Then XRD was used to study the composition and difference of clay mineral in two kinds of soil and the evolutionary mechanism was explored. The results showed that the two kinds of soil particles were composed mainly of the sand, followed by clay and silt. When the particle accumulation rate reached 50%, the central particle size was in the 15-130 microm interval. Except for black soil profile of Shengli Xiang, the content of clay showed converse sequence to the central particle in two soils. Clay accumulated under upper layer (18.82%) in black soil profile while under caliche layer (17.41%) in chernozem profile. Clay content was the least in parent material horizon except in black profile of Quanyanling. Analysis of clay XRD atlas showed that the difference lied in not only the strength of diffraction peak, but also in the mineral composition. The main contents of black soil and chernozem were both 2 : 1 clay, the composition of black soil was smectite/illite mixed layer-illite-vermiculite and that of chernozem was S/I mixture-illite-montmorillonite, and both of them contained little kaolinite, chlorite, quartz and other primary mineral. This paper used XRD to determine the characteristics of clay minerals comprehensively, and analyzed two kinds of typical cultivated soil comparatively, and it was a new perspective of soil minerals study.

Development, validation, and application of a liquid chromatography-tandem mass spectrometry method for the determination of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol in human hair.

The tobacco-specific nitrosamine metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is a valuable biomarker for human exposure to the carcinogenic nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in tobacco and tobacco smoke. In this work, an efficient and sensitive method for the analysis of NNAL in human hair was developed and validated. The hair sample was extracted by NaOH solution digestion, purified by C(18) solid-phase extraction (SPE) and molecularly imprinted solid-phase extraction, further enriched by reverse-phase ultrasound-assisted dispersive liquid-liquid microextraction (USA-DLLME) into 1.0 % aqueous formic acid, and finally analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry. Good linearity was obtained in the range of 0.24-10.0 pg/mg hair with a correlation coefficient of 0.9982, when 150 mg hair was analyzed. The limit of detection and lower limit of quantification were 0.08 and 0.24 pg/mg hair, respectively. Accuracies determined from hair samples spiked with three different levels of NNAL ranged between 87.3 and 107.7 %. Intra- and inter-day relative standard deviations varied from 4.1 to 8.5 % and from 6.9 to 11.3 %, respectively. Under the optimized conditions, an enrichment factor of 20 was obtained. Finally, the developed method was applied for the analysis of NNAL in smokers' hair. The proposed sample preparation procedure combining selectivity of two-step SPE and enrichment of DLLME significantly improves the purification and enrichment of the analyte and should be useful to analyze NNAL in hair samples for cancer risk evaluation and cancer prevention in relation to exposure to the tobacco-specific carcinogen NNK.

Pretreatment of Rho kinase inhibitor inhibits systemic inflammation and prevents endotoxin-induced acute lung injury in mice.

BACKGROUND: Systemic inflammatory mediators play an important role in the development of sepsis. In this study, we analyzed the role of Rho kinase in the activation of immune response and acute lung injury in a mouse model of sepsis. METHODS: C57BL/6J mice were randomly divided into three groups: control, LPS, and LPS+fasudil. We used a mouse model of endotoxemia that consists of intraperitoneal injection of a high dose of LPS (30 mg/kg); a Rho kinase inhibitor, fasudil (10 mg/kg), dissolved in sterile saline (1 µL/g body weight) was applied by intraperitoneal injection at 18 and 1 h before injection of LPS (LPS+fasudil group). The control mice received vehicle sterile saline only. Blood was collected and lungs were harvested at 3 and/or 6 h for analysis. RESULTS: At 3 and 6 h, the increased TNF-α and IL-1ß levels in plasma and MPO activity in lung tissue by LPS could be significantly inhibited by fasudil. In addition, LPS-induced histologic changes in the lungs at 6 h could be effectively reversed by fasudil pretreatment. Furthermore, pretreatment of mice with fasudil inhibited LPS-induced increasing of TNF-α, IL-1ß mRNA expression (3 and 6 h) and AP-1/DNA binding activity (3 h) in blood cells. In survival studies, fasudil (10 mg/kg), which was administered 18 and 1 h before the application of LPS, conferred a protection against lethality induced by LPS (30 mg/kg). CONCLUSION: These results suggest that Rho kinase may play a role in the pathology of systemic inflammation during early phase of sepsis, and the potential mechanism of action may be partly through the adjustment of AP-1 pathway.

Usefulness of metagenomic next-generation sequencing in adenovirus 7-induced acute respiratory distress syndrome: A case report.

BACKGROUND: Direct metagenomic next-generation sequencing (mNGS) of clinical samples is an effective method for the molecular diagnosis of infection. However, its role in the diagnosis of patients with acute respiratory distress syndrome (ARDS) of an unknown infectious etiology remains unclear. CASE SUMMARY: A 33-year-old man was admitted to our center for a cough and febrile sensation. Shortly after admission, the patient was diagnosed with ARDS and treated in the intensive care unit. Subsequently, chest computed tomography features suggested an infection. mNGS was performed and the results were indicative of an infection caused by adenovirus type 7. The patient recovered after receiving appropriate treatment. CONCLUSION: mNGS is a promising tool for the diagnosis of ARDS caused by infectious agents. However, further studies are required to develop strategies for incorporating mNGS into the current diagnostic process for the disease.

[Evaluation of clinical effects on low-dose heparin therapy for sepsis].

OBJECTIVE: To investigate the therapeutic effects of low-dose heparin on sepsis. METHODS: Seventy-nine sepsis patients were randomly divided into two groups: heparin treatment group (n = 37) and routine treatment group (n = 42). The 7-day and 28-day mortality, the days in ICU and the length of stay, the changes of oxygenation index, the days of mechanical ventilation and the rates of disseminated intravascular coagulation (DIC), acute renal failure (ARF), acute respiratory distress syndrome (ARDS) and multiple organ dysfunction syndrome (MODS) were observed. The levels of APTT, PT and platelet (PLT) count were determined before and after treatment in two groups. RESULTS: The rates of DIC, ARF and MODS in heparin group decreased significantly after therapy: rate of DIC, 15.4% vs 38.7% (P = 0.03); rate of ARF, 25.0% vs 51.9% (P = 0.04); rate of MODS, 26.3% vs 50.0% (P = 0.04). In heparin group, the 28-day mortality was statistically reduced (15.4% vs 32.4%, P = 0.03). The differences between heparin group and routine group were not statistically significant in the 7-day mortality (7.7% vs 12.9%, P = 0.08), the days in ICU (Z = 0.281, P = 0.779, rank sum test), the length of stay (Z = 0.562, P = 0.574, rank sum test), the oxygenation index (P = 0.82), the days of mechanical ventilation [(126.07 +/- 166.21) h vs (179.27 +/- 221.7) h, P = 0.28] and the rate of ARDS (44.0% vs 46.2%, P = 0.88). The differences in APTT, PT and PLT were not significant between the two groups. CONCLUSION: Low-dose heparin can decrease the mortality rate of sepsis and improve the prognosis of patients. It is a safe promising therapy in sepsis patients without severe side effects.

Prognostic value of red blood cell distribution width for severe acute pancreatitis.

BACKGROUND: Severe acute pancreatitis (SAP) is a common condition in the intensive care unit (ICU) and has a high mortality. Early evaluation of the severity and prognosis is very important for SAP therapy. Recently, red blood cell distribution (RDW) was associated with mortality of sepsis patients and could be used as a predictor of prognosis. Similarly, RDW may be associated with the prognosis of SAP patients and be used as a prognostic indicator for SAP patients. AIM: To investigate the prognostic value of RDW for SAP patients. METHODS: We retrospectively enrolled SAP patients admitted to the ICU of the First Affiliated Hospital of China Medical University from June 2015 to June 2017. According to the prognosis at 90 d, SAP patients were divided into a survival group and a non-survival group. RDW was extracted from a routine blood test. Demographic parameters and RDW were recorded and compared between the two groups. The receiver operator characteristic (ROC) curve was constructed and Cox regression analysis was performed to investigate the prognostic value of RDW for SAP patients. RESULTS: In this retrospective cohort study, 42 SAP patients were enrolled, of whom 22 survived (survival group) and 20 died (non-survival group). The baseline parameters were comparable between the two groups. The coefficient of variation of RDW (RDW-CV), standard deviation of RDW (RDW-SD), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and Sequential Organ Failure Assessment (SOFA) score were significantly higher in the non-survival group than in the survival group (P < 0.05). The RDW-CV and RDW-SD were significantly correlated with the APACHE II score and SOFA score, respectively. The areas under the ROC curves (AUCs) of RDW-CV and RDW-SD were all greater than those of the APACHE II score and SOFA score, among which, the AUC of RDW-SD was the greatest. The results demonstrated that RDW had better prognostic value for predicting the mortality of SAP patients. When the RDW-SD was greater than 45.5, the sensitivity for predicting prognosis was 77.8% and the specificity was 70.8%. Both RDW-CV and RDW-SD could be used as independent risk factors to predict the mortality of SAP patients in multivariate logistic regression analysis and univariate Cox proportional hazards regression analysis, similar to the APACHE II and SOFA scores. CONCLUSION: The RDW is greater in the non-surviving SAP patients than in the surviving patients. RDW is significantly correlated with the APACHE II and SOFA scores. RDW has better prognostic value for SAP patients than the APACHE II and SOFA scores and could easily be used by clinicians for the treatment of SAP patients.

Pseudolaric acid B exhibits anti-cancer activity on human hepatocellular carcinoma through inhibition of multiple carcinogenic signaling pathways.

BACKGROUND: Pseudolaric acid B (PAB), a diterpene acid isolated from the root bark of Pseudolarix kaempferi, exhibits a potent anti-cancer activity in a variety of tumor cells. PURPOSE: The present study was designed to evaluate the anti-cancer effects of PAB on hepatocellular carcinoma (HCC) cell lines in vitro, and to explore the underlying mechanism. METHODS: The anti-proliferative activity of PAB on HCC cells were assessed via sulforhodamine B staining, colony formation, cell cycle analysis, respectively. Apoptosis was detected using Annexin V/propidium iodide double staining and diamidino-phenyl-indole staining, respectively. Protein expression regulated by PAB treatment was tested by western blotting. RESULTS: The present results showed that PAB significantly inhibited the proliferation of HepG2, SK-Hep-1, and Huh-7 HCC cell lines in vitro with IC50 values of 1.58, 1.90, and 2.06 µM, respectively. Furthermore, PAB treatment repressed the colony formation in HepG2, SK-Hep-1, and Huh-7 HCC cell lines. Flow cytometry analysis revealed that PAB caused an obvious cell cycle arrest in G2/M phase and induced apoptosis with the induction of p21, Bax, cleaved-caspase-3, and cleaved-PARP in human HepG2 and SK-Hep-1 cells. Mechanistically, PAB treatment down-regulated the phosphorylation of STAT3, ERK1/2, and Akt. Moreover, abnormal GSK-3ß/ß-catenin signaling in HepG2 cells was remarkably suppressed by PAB treatment. Finally, proliferation markers including cyclin D1 and c-Myc, and anti-apoptosis proteins such as Bcl-2 and survivin were also down-regulated by PAB treatment in HepG2 cells. CONCLUSION: Taken together, our results suggest that PAB exerts anti-cancer activity in HCC cells through inhibition of STAT3, ERK1/2, Akt, and GSK-3ß/ß-catenin carcinogenic signaling pathways, and may be used as a phytomedicine in the treatment of HCC.

[Therapeutic effects of low molecular weight heparin and aspirin on acute lung injury in rat].

OBJECTIVE: To investigate the possible effects of nuclear factor-KappaB (NF-KappaB) activation on the expression of intercellular adhesion molecular-1 (ICAM-1) and P-selectin in murine acute lung injury (ALI) and assess the potential beneficial effects and mechanism of low molecular weight heparin (LMWH) and aspirin (ASA). METHODS: Rat ALI model was reproduced by injection of lipopolysaccharide into tail vein. Sixty rats were divided randomly into four groups (n=15): normal control group, ALI group, LMWH group and ASA group. The change in NF-KappaB activity in the lung to show its relation with ICAM-1 and P-selectin was observed by immunohistochemistry. RESULTS: Compared with normal control group, the activity of NF-KappaB and the expression of ICAM-1 and P-selectin increased significantly in the lung tissue of ALI group (all P<0.05). Compared with ALI group, the level of NF-KappaB activity and the expression of ICAM-1 and P-selectin were obviously down regulated, and also the pathological lesion and inflammatory response of lung were improved in LMWH and ASA groups. However, the therapeutic effects of ASA were stronger than those of LMWH (all P<0.05). CONCLUSION: NF-KappaB activation plays an important role in ALI. NF-KappaB takes part in the activation of many kinds of inflammatory cells such as neutrophil, endothelial cells and so on, and it adjusts the genetic expression of ICAM-1 and P-selectin. LMWH and ASA show their beneficial effects on lung injury in both functional and morphological aspects. But the mechanism is different. LMWH can indirectly inhibit the activation of NF-KappaB, improve lung microcirculation and decrease the adhesion of neutrophil and platelet. ASA plays the role as an inhibitor of NF-KappaB activation.

[Study on the relationship between endocrine hormone and prognosis in critically ill patients].

OBJECTIVE: To investigate the profile and significance of changes in thyroid function and cortisol in critically ill patients. METHODS: Chemiluminescent microparticle immunoassay (CMIA) was used to measure the serum thyroid hormone, thyroid stimulating hormone and cortisol levels in 51 patients at the first day and in the 45 patients still alive at the third day after hospitalized in ICU. In the 45 patients, 17 cases were complicated with multiple organ dysfunction syndrome (MODS) and 28 cases were not. The age, blood glucose levels and APACHE II scores were also recorded at the first day. RESULTS: In the 45 patients, serum FT(3) decreased in 41 patients (91%), cortisol increased in 33 patients (73%), especially in the first 24 hours. Compared with non-MODS group, serum FT(3), FT(4) and cortisol levels changed significantly in MODS group. Serum FT(4) reduced apparently in 6 dead patients. Serum FT(3) level was negatively correlated with APACHE II, and cortisol level was positively correlated with APACHE II. CONCLUSIONS: Thyroid hormone and cortisol were apparently abnormal and correlated with APACHE II score, especially in patients with MODS. Serum FT(4) might serve as an index to judge the prognosis of the patients.

Synthesis of Demissidine and Solanidine.

Demissidine and solanidine, two steroidal alkaloids, are synthesized in eight steps from tigogenin acetate and diosgenin acetate, respectively, which involve the replacement of three C-O bonds with C-N bonds. Key transformations include a cascade ring-switching process of furostan-26-acid, an epimerization of C25, an intramolecular Schmidt reaction, and an imine reduction/intramolecular aminolysis process.

Effects of improving nitrogen management on nitrogen utilization, nitrogen balance, and reactive nitrogen losses in a Mollisol with maize monoculture in Northeast China.

Traditional fertilization led to higher apparent N surplus, and optimized fertilization can reduce residual nitrogen in soils with keeping high yield. But in continuous spring maize cropping zone in Mollisol in Northeast China, the effect of the optimized N management on N balance and comprehensive environment was not clear. The primary objective of this study was to compare the differences of two fertilizations (traditional farmer N management (FNM) with single basal fertilizer and improvement N management (INM) by soil testing with top-dressing) in gain yield, N uptake and N efficiency, soil N balance, reactive N losses, and environment assessment. The results showed that INM treatment has no remarkable effect on grain yield and N uptake; N partial factor productivity (PFPN) of INM treatment was 19.8 % significantly higher than the FNM treatment. Nmin in soils of INM treatment reached to 111.0 kg ha(-1), which was 27.1 % lower than the FNM treatment after 6 years of continuous maize cropping; the apparent N Losses (ANL) and apparent N surplus (ANS) of INM were only half of FNM by soil N balance analysis. In reactive N losses, comparing with FNM treatment, INM treatment reduced NH3 volatilization, N2O emission, N leaching, and N runoff by 17.8, 35.6, 45, and 38.3 %, respectively, during planting period, and in integrated environment assessment by life cycle assessment (LCA) method, producing 1 t maize grain, energy depletion, acidification, eutrophication, and climate change impacts of INM treatment decreased 26.19, 30.16, 32.61, and 22.75 %, respectively. Therefore, INM treatment is a better N management strategy in comprehensive analysis.

[Regulation of four typical scenic recreational plantations to stand PM2.5 concentration in Beijing, China].

To study the variation of PM2.5 concentration in scenic recreational plantations and its response to meteorological factors, and to analyze the regulation effect of different stands on PM2.5 concentration, in the summer, autumn and winter of 2013, PM2.5 concentration and relevant meteorological factors in four typical scenic recreational plantations (Pinus armandii--Ginkgo biloba mixed plantation, Populus tomentosa--Fraxinus chinensi mixed plantation, Populus tomentosa pure plantation, multiple-species-layered mixed plantation) were simultaneously monitored, in Beijing Olympic Forest Park (the observation was conducted continuously for 28 days). The results showed that the daily variation of PM2.5 concentration in the four stands didn' t represent a unified pattern at different air pollution levels, but were basically consistent at the same pollution level. When the wind force was 0-2 grade, there was no significant difference among daily average PM2.5 concentrations [the average PM2.5 concentration during the observation period (9:00-15:00) ] in the four stands at each pollution level. Stand PM2.5 concentration was positively correlated to air relative humidity (P < 0.01), negatively correlated with air temperature (P < 0.05), but uncorrelated with wind speed. Changed percentage of stand PM2.5 concentration compared to the space varied between -21.4% and 33.2%, and it was negatively correlated with air relative humidity (P < 0.05), but not correlated with the wind speed and air temperature. The regulation effects of the four stands on PM2.5 concentration included both increasing and decreasing effects, and in this study, the critical value of air relative humidity was 67% when this regulation shifted.

[Exploration of a quantitative methodology to characterize the retention of PM2.5 and other atmospheric particulate matter by plant leaves: taking Populus tomentosa as an example].

Taking Populus tomentosa as an example, a methodology called elution-weighing-particle size-analysis (EWPA) was proposed to evaluate quantitatively the ability of retaining fine particulate matter (PM2.5, diameter d ≤ 2.5 µm) and atmospheric particulate matter by plant leaves using laser particle size analyzer and balance. This method achieved a direct, accurate measurement with superior operability about the quality and particle size distribution of atmospheric particulate matter retained by plant leaves. First, a pre-experiment was taken to test the stability of the method. After cleaning, centrifugation and drying, the particulate matter was collected and weighed, and then its particle size distribution was analyzed by laser particle size analyzer. Finally, the mass of particulate matter retained by unit area of leaf and stand was translated from the leaf area and leaf area index. This method was applied to a P. tomentosa stand which had not experienced rain for 27 days in Beijing Olympic Forest Park. The results showed that the average particle size of the atmospheric particulate matter retained by P. tomentosa was 17.8 µm, and the volume percentages of the retained PM2.5, inhalable particulate matter (PM10, d ≤ 10 µm) and total suspended particle (TSP, d ≤ 100 µm) were 13.7%, 47.2%, and 99.9%, respectively. The masses of PM2.5, PM10, TSP and total particulate matter were 8.88 x 10(-6), 30.6 x 10(-6), 64.7 x 10(-6) and 64.8 x 10(-6) g x cm(-2) respectively. The retention quantities of PM2.5, PM10, TSP and total particulate matter by the P. tomentosa stand were 0.963, 3.32, 7.01 and 7.02 kg x hm(-2), respectively.

High glucose enhances LPS-stimulated human PMVEC hyperpermeability via the NO pathway.

Chronic hyperglycemia is an established risk factor for endothelial damage. It remains unclear, however, whether brief hyperglycemic exposure exacerbates the damage to vascular endothelial cells induced by endotoxin. We hypothesize that brief hyperglycemic exposure enhances the permeability of the endothelium following stimulation with lipopolysaccharide (LPS). Correlations between modulation of nitric oxide synthase (NOS) pathways and altered endothelial homeostasis have been studied and demonstrated in various pathophysiological conditions. NOS activities are regulated by endogenous inhibitors, including asymmetric dimethylarginine (ADMA), which is metabolized by dimethylarginine dimethylaminohydrolase (DDAH). Since previous data demonstrated that endothelial dysfunction may be related to reduced expression and/or activity of DDAH, in this study, we aimed to determine the effect of increased glucose levels on pulmonary microvascular endothelial cell (PMVEC) permeability, including effects on the NOS pathways. Human PMVECs were incubated with normal (5.5 mM) and high (33 mM) concentrations of D-glucose for 5 days to create a monolayer of cells prior to LPS stimulation (10 µg/ml) for 12 h. When stimulated with LPS, cells incubated with a high glucose (HG) concentration had significant microfilament rearrangement compared with cells incubated with a normal glucose concentration, as determined by immunofluorescence. Scanning electron microscopy revealed a larger average diameter and increased number of fenestrae on the hyperglycemic PMVECs when stimulated with LPS, compared with PMVECs cultured with a normal glucose concentration. The results demonstrated that a high concentration of glucose increases the LPS-stimulated horseradish peroxidase (HRP) permeability compared with a normal concentration of glucose. Furthermore, a HG concentration upregulated LPS-stimulated inducible NOS (iNOS) production and down-regulated endothelial NOS (eNOS) and DDAH-2 expression. Hyperglycemia significantly increased LPS-stimulated nitrite/nitrate production (stable NO end-products). Our results, thus, demonstrate that in vitro HG concentrations exacerbate LPS-stimulated cytoskeletal rearrangement and hyperpermeability of an endothelial monolayer, and cause further imbalance of the NO pathway. These results suggest that it is important to manage even short-term increases in blood glucose, particularly following acute infection.

[High glucose enhances permeability of human pulmonary microvascular endothelial cells by lipopolysaccharide stimulation in vitro and effect of DDAH/NOS/NO imbalance on its pathogenesis].

OBJECTIVE: To investigate the damage to endothelial cells incubated in high concentration of glucose challenged by lipopolysaccharide (LPS), and the likely mechanisms of injury. METHODS: Human pulmonary microvascular endothelial cells (PMVECs) were divided into the following groups: normal glucose group (NG), normal glucose + LPS stimulation group (NGL), high glucose stimulation group (HG), and high glucose + LPS stimulation group (HGL). The cells were incubated with normal glucose (5.5 mmol/L, contained 10% calf serum) or high glucose (33 mmol/L) for 5 days to form a monolayer of cells before LPS stimulation (10 mg/L) for 24 hours. The microfilaments (F-actin) were investigated by immuno-fluorescence, and the number and size change in fenestrae were examined by scanning electron microscopy. The permeability of vascular endothelial cell was assessed by trans-PMVEC horseradish peroxidase (HRP) flux. Western blotting was used to determine the expressions of dimethylarginine dimethylaminohydrolase 2 (DDAH2), inducible nitricoxide synthase (iNOS) and endothelial nitricoxide synthase (eNOS). Nitric oxide (NO) was assessed by Griess method. RESULTS: When stimulated with LPS, cells incubated with high glucose showed obvious microfilament rearrangement, a larger average diameter and increased number of F-actin, as well as higher HRP permeability on the hyperglycemic PMVECs compared with PMVECs cultured with normal glucose [(53.62±6.70)% vs. (23.63±3.92)%, P<0.01]. Furthermore, high glucose down-regulated DDAH2 expression (arbitrary units, AU, 0.33±0.08 vs. 0.77±0.14 , P<0.01) and up-regulated LPS-stimulated iNOS production (1.40±0.29 vs. 1.04±0.09, P<0.01), as well as increased LPS-stimulated nitrite/nitrate and stable NO end products compared with normal (20.36±2.25 µmol/L vs. 7.99±0.33 µmol/L, P<0.01) and reduction of eNOS levels was observed (0.67±0.09 vs. 0.91±0.17, P<0.05). CONCLUSION: It demonstrated that, in vitro high glucose deteriorate LPS-stimulated F-actin rearrangement and hyperpermeability of an endothelial monolayer, and the worsened imbalance of the NO pathway may lead to endothelial damage in microcirculation.