Role of endoplasmic reticulum stress-mediated apoptosis in proanthocyanidins-induced attenuation of intestinal ischemia-reperfusion injury in mice / 中华麻醉学杂志

Objective:To evaluate the role of endoplasmic reticulum stress-mediated apoptosis in proanthocyanidins-induced attenuation of intestinal ischemia-reperfusion (I/R) injury in mice.Methods:Thirty SPF healthy adult male C57BL/6 mice, aged 8-10 weeks, weighing 20-25 g, were divided into 5 groups ( n=6 each) by a random number table method: sham operation group (S group), sham operation + proanthocyanidins group (S+ PC group), intestinal I/R group (I/R group), intestinal I/R + proanthocyanidins group (I/R+ PC group) and intestinal I/R + proanthocyanidins + tunicamycin group (I/R+ PC+ TM group). The superior mesenteric artery was clamped for 60 min and reperfused for 120 min to establish a mouse intestinal I/R injury model.Proanthocyanidin 100 mg/kg was given by intragastric gavage every day 1 week before ischemia in S+ PC group, I/R+ PC group and I/R+ PC+ TM group, and the equal volume of normal saline was given for 7 consecutive days in S group and I/R group, and endoplasmic reticulum stress agonist tunicamycin 1 mg/kg was intraperitoneally injected at 24 h before ischemia in I/R+ PC+ TM group.The mice were sacrificed at 120 min of reperfusion, and the small intestinal tissues were taken for microscopic examination of the histopathological changes (using light microscopy) and for determination of the level of diamine oxidase (DAO) (by enzyme-linked immunosorbent assay), cell apoptosis (by TUNEL method), glucose regulatory protein 78 (GRP78), C/EBP-homologous protein (CHOP) and cleaved caspase-3, Bax and Bcl-2 (by Western blot). Intestinal damage was assessed and scored according to Chiu, and the apoptosis index (AI) and Bcl-2/Bax ratio were calculated. Results:Compared with S group, the Chiu′s score, level of DAO and AI were significantly increased, the expression of GRP78, CHOP, cleaved caspase-3 and Bax was up-regulated, the expression of Bcl-2 was down-regulated, the ratio of Bcl-2/Bax was decreased( P<0.05), and the pathological damage occurred in the small intestinal tissue in I/R group, and no significant change was found in the aforementioned indexes in S+ PC group ( P>0.05). Compared with I/R group, the Chiu′s score, DAO level and AI were significantly decreased, the expression of GRP78, CHOP, cleaved caspase-3 and Bax was down-regulated, the expression of Bcl-2 was up-regulated, the ratio of Bcl-2/Bax was increased( P<0.05), and the pathological injury to the small intestinal tissue was significantly reduced in I/R+ PC group. Compared with I/R+ PC group, the Chiu′s score, level of DAO and AI were significantly increased, the expression of GRP78, CHOP, cleaved caspase-3 and Bax was up-regulated, the expression of Bcl-2 was down-regulated, and the ratio of Bcl-2/Bax was decreased( P<0.05), and the pathological damage to the small intestinal tissue was aggravated in I/R+ PC+ TM group. Conclusions:Proanthocyanidins can alleviate intestinal I/R injury by inhibiting endoplasmic reticulum stress-mediated cell apoptosis in mice.

Molecular mechanism of lutein protecting Müller cells against oxidative stress induced by H2O2 / 中华实验眼科杂志

Background Oxidative stress is a main cause of age-related macular degeneration (AMD).Lutein has a preventive role for AMD, but its antioxidant mechanism remains unclear.Objective Present study was to investigate the effect of lutein on oxidative stress of Müller cells and its signaling pathway.Methods Human Müller cells (human Müller cell strain) were cultured, and the cells at logarithmimic growth phase were incubated in 96 well plate overnightly.Oxidative stress cell models were established by adding 160 μmol/L H2O2, a median lethal dose for Müller cells.The models were divided into the model control group and 12.5,25.0,50.0 mg/L lutein groups,and the different concentrations of lutein were used to culture the cells for 24 hours, respectively.The routine cultured cells served as the blank control group.Growth of the cells was assayed by MTT method (absorbancy);the reactive oxygen species (ROS) content in the cells was assayed by flow cytometry;the mRNA and protein levels of nuclear factor-E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in the cells were detected by quantitative real-time PCR and Western blot, respectively.Results The inhibitory effects on the cells were gradually enhanced with the increase of H2O2 concentrations,showing a significant difference among the groups (F =43.890,P＜0.01).A significant difference was found in apoptotic rate of the cells among the blank control group,model control group and 12.5,25.0,50.0 mg/L lutein groups (F =346.770, P =0.000) , and the apoptosis rate was significant elevated with the increase of lutein dose (all at P＜0.05).The ROS contents in the cells were 1.92±0.18,64.89±2.86,52.70±2.80,32.61 ±4.20 and 5.68 ± 1.35 in the blank control group, model control group and 12.5,25.0,50.0 mg/L group, respectively, with significant difference among the groups (F =324.900, P =0.000), and the ROS content was gradually reduced as the increase of lutein dose (all at P＜0.05).The relative mRNA and protein expressions of Nrf2 and HO-1 were remarkedly higher in the 12.5,25.0,50.0 mg/L lutein groups than those in the model control group (F =236.960,242.620,186.830,263.120, all at P =0.000) , and no significant difference was seen in the relative expression level of nuclear Nrf2 protein among the groups (F =1.790, P =0.210).Conclusions Lutein can induce the expression of antioxidant enzymes by inducing the expression of nuclear translocation of Nrf2 and consequently inhibit the oxidative stress status.

Physiological attributes of lichen, Phaeophyscia hispidula in heavy metal rich sites of Dehra Dun, India.

Phaeophyscia hispidula (Ach.) Moberg, foliose lichen is widespread in Garhwal Himalayas and grows luxuriantly on different substratum in polluted as well as non polluted sites, where no other macrolichens are able to colonize. The elemental concentration and biochemical parameters in P. hispidula collected from Dehra Dun city were analyzed to assess its tolerance to heavy metals. The major source of pollution in the city is automobiles. Among the biochemical parameters protein was significantly and negatively correlated with pigment concentrations (r= -0.3838 (Chl.b); -0.5809 (Carotenoid); -0.5034 (OD)) however it is significantly positively correlated with Cd (r = 0.6822: P<0.01). Among heavy metals, Cd was negatively correlated with Cu (r = -0.4639), Fe (r = -0.2676), and Zn (r = -0.0549). It was observed that the chlorophyll and protein content increased parallel to the level of metallic pollutants indicating the mechanism of stress tolerance in P. hispidula. The study shows that P. hispidula is tolerant to inorganic pollution and a useful tool for biomonitoring of air quality in the Himalayan region.

Biomarcadores d estrés como indicadores de bieestar animal en Ganado de carnee: stress biomarkers as indicators of animal welfare in cattle beef farming

La presente revisión presenta los cambios fisiológicos que presentan los bovinos durante el estrés agudo, así como los biomarcadores sanguíneos utilizados para medir su impacto en el bienestar animal. Durante el presacrificio, el ganado es expuesto con frecuencia a diferentes factores que causan agotamiento físico y estrés fisiológico, los cuales pueden tener efectos adversos para la salud, el bienestar animal y la calidad de la carne. Los más comunes factores son: velocidad y movimientos bruscos del camión, ruido, fuerza centrífuga, ruptura de la estructura social debido a la mezcla de animales, ambiente extraño, manejo rudo de los bovinos durante el cargue y descargue, condiciones climáticas, privación de alimento y agua, entre otros. El estrés ha sido utilizado como un indicador de bienestar animal. Este altera la homeostasis interna de los animales induciendo cambios en la actividad del eje hipotálamo-pituitaria-adrenocortical (HPA) y el sistema simpático-adreno-medular. La activación endocrina promueve la liberación de varias hormonas: catecolaminas, especialmente adrenalina y noradrenalina; hormona liberadora de corticotropina (CRH); hormona adrenocorticotrópica (ACTH) y corticosteroides, principalmente cortisol. Diferentes autores han utilizado distintos constituyentes sanguíneos para determinar el estrés. El cortisol, a pesar de su variabilidad y vida corta, sigue siendo uno de los indicadores más usados. Estos autores también han usado el volumen celular acumulado (VGA), la concentración de glucosa, la actividad de la enzima creatinfosfoquinasa (CK), las concentraciones de B-hidroxibutirato y lactato, como indicadores de estrés. La determinación de estos biomarcadores es un método práctico para monitorear el bienestar animal en ganado bovino de carne.

The present review presents the physiological changes that occur in cattle during acute stress, as well as blood biomarkers used to measure their impact on animal welfare. During the pre-slaughter process, cattle are often exposed to different factors that cause physical exhaustion and physiological stress which can have adverse effects on health, animal welfare, and meat quality. The most common stressors are: fast and forced movements of the truck, centrifuged force, breakdown of the social structure due to mixing of the animals, strange environment, rough treatment of cattle during loading and unloading, weather conditions, deprivation of feed and water among others. Stress has been identified as an indicator of animal welfare. Stress alters the internal animal homeostasis inducing changes in the hypothalamic-pituitary-adrenocortical (HPA) axis and the sympatho-adreno-medullary system. The endocrine activation promotes the release of several hormones: catecholamines, mainly adrenaline and noradrenaline; corticotrophin-releasing hormone (CRH); adrenocorticotrophin (ACTH) and corticosteroids, mainly cortisol. Different authors have used several blood constituents to determine stress. Cortisol, despite its variability and short life, is still one the most used indicators of stress. These authors have also used the packed cell volume (PCV), glucose concentration, creatine phosphokinase (CK) activity, B-hidroxybutyrate and lactate concentration as stress indicators. The determination of these biomarkers is a practical method to monitor animal welfare in cattle beef.

Pré-eclâmpsia: estresse oxidativo, inflamação e disfunção endotelial / Preeclampsia: oxidative stress, inflammation and endothelial dysfunction

Pré-eclâmpsia é uma síndrome sistêmica caracterizada por intenso estado inflamatório e antiangiogênico. A fisiopatologia da pré-clâmpsia envolve alterações no processo de invasão trofoblástica, com consequente inadequado suprimento sanguíneo uterino e estresse oxidativo do tecido placentário. As alterações placentárias decorrentes desse processo levam à maior produção de sFlt-1, um receptor solúvel para as moléculas de VEGF e PlGF. O sFlt-1 impede com que VEGF e PlGF realizem suas funções na homeostase endotelial, culminando com disfunção dessas células. De uma maneira geral, os processos inflamatórios, de disfunção endotelial e estresse oxidativo estão interligados e agem de maneira sinérgica. Trabalhos recentes têm demonstrado que elevações nas concentrações séricas de sFlt-1 ocorrem 5 a 6 semanas antes das manifestações clínicas da pré-eclâmpsia. Concomitantemente, observa-se queda nas concentrações séricas de PlGF. Sendo assim, as dosagens séricas de sFlt-1 e PlGF têm sido sugeridas para o diagnóstico precoce de pré-eclâmpsia. Ademais, os conhecimentos adquiridos a respeito dos fatores antiangiogênicos proporcionam ainda a possibilidade de novas linhas de pesquisa sobre possíveis terapias para a pré-eclâmpsia. Neste artigo, foram revisados os aspectos inflamatórios e antiangiogênicos envolvidos na fisiopatologia da pré-eclâmpsia. Por fim, foram correlacionados esses aspectos com o risco elevado para doenças cardiovasculares apresentado por essas pacientes ao longo de suas vidas.

Preeclampsia is a systemic syndrome characterized by inflammatory and antiangiogenic states. The pathogenesis of preeclampsia involves deficient trophoblast invasion that is responsible for altered uterine blood flow and placental oxidative stress. The damaged placenta produces higher concentrations of sFlt-1, a soluble receptor for VEGF and PlGF that is released in the maternal circulation and is involved in endothelial dysfunction. Actually, all processes involved in inflammation, endothelial dysfunction and oxidative stress are strongly correlated and act in a synergistic way. Recent data have shown that an increase in serum concentrations of sFlt-1 initiates 5 to 6 weeks before the clinical manifestations of preeclampsia and these alterations correlate with a decrease in serum concentrations of PlGF. Therefore, both sFlt-1 and PlGF have been suggested to be useful for an early-diagnosis of preeclampsia. The knowledge about the role of antiangiogenic factors in the pathogenesis of preeclampsia has raised the possibility of a therapy involving these factors.In this article we revisited the pathogenesis of preeclampsia addressing its antiangiogenic and inflammatory states.In conclusion, we correlated these alterations with the higher risk for cardiovascular diseases presented by these women in future life.

Progress in Forest Tree Proteomics Research / 中国生物工程杂志

Considerable knowledge about the biology of forest tree has been gained in the recent years by the application of the new genomic technologies to study tree growth and development as well as the response of trees to biotic and abiotic stresses. Proteomics is becoming an important content in the biology of forest tree. A review is given about the progress in forest tree proteomics research in the areas of population genetics, genetic mapping, stress physiology, organs and tissues, and wood formation, etc. Furthermore, forest tree proteome database is briefly introduced. Finally, the prospect of proteomics is discussed.

The Protection against +Gz Afforded by Pressure Breathing with Different Pressure Schedules / 航天医学与医学工程

Objective System of pressure breathing for +Gz (PBG) has been incorporated into service in the high performance fighter aircraft,but there were significant differences among PBG pressure schedules used in different countries.The purpose of this study was to define an optimal pressure schedule in PBG system.Method Five male subjects wearing GZ-2 anti-G suit and medium-sized bladder vest,plus PBG with 1.6,2.4,and 3.2 kPa/G pressure schedules,respectively,were exposed to rapid onset (3.0 G/s) centrifuge +Gz runs.+Gz protection of PBG with each of the three pressure schedules were measured and the subjective ratings were collected.Result The +Gz protection afforded by PBG with 1.60,2.40,and 3.20 kPa/G pressure schedules were 2.00±0.31,2.54±0.32,and 2.44±0.31 G,respectively.Subjective ratings showed that the PBG with 2.40 kPa/G pressure schedule was better than the other two.Conclusion Our data suggest that a PBG pressure schedule of 2.4 kPa/G in PBG system is optimal.It not only assures the anti-G performance of PBG,but also reduces its side effects.

Effects of Tea Polyphenols on Cardiac Function and Myocardial Ultrastructure in Rats after Repeated +Gz Stress / 航天医学与医学工程

Objective To observe the effects of tea polyphenols (TP) on cardiac function and myocardial ultrastructure in rats after repeated +10 Gz stress. Method Twenty four male Wistar rats were randomly divided into three groups (n=8 each): group A (control), group B (+10 Gz), group C (+Gz with TP). Group B and C were repeatedly exposed to +10 Gz (each for 30 s, onset rate about 0.5 G/s, 3 times/d with +1 Gz 1 min intervals, 3 d/wk, 4 weeks in total), but group A was only submitted to +1 Gz. TP(200 mg.kg-1) was given orally to group C about 1h prior to the +Gz experiment, and distilled water was given to group A and B.Function of isolated rat working hearts and myocardial ultrastructure were observed. Result A significant decrease of left ventricular systolic pressure (LVSP) and injury of myocardial structure in rats were demonstrated after repeated +10 Gz stress. But TP could remarkably elevate the LVSP and improve myocardial ultrastructural injury in +10Gz stressed rats. Conclusion These results indicated that repeated high G exposure may produce cardiac structural and functional injuries in rats which might be partly related to free radical metabolism; and antioxidant TP had significant protective effects on the hearts of +Gz stressed rats.

Biochemical Changes of Plasma in Paratroops after Parachuting:A Preliminary Investigation / 航天医学与医学工程

Objective To study whether physiological and psychological stresses during parachuting jumps may result in biochemical changes of plasma in parachutists. Method Differences in the levels of hormones (cortisol, growth hormone, insulin, pancreatic glucagon, endothelin, angiotonin I and II, aldosterone), activities of enzymes (superoxide dismutase, glutathione peroxidase, glutathione S transferase), levels of the free radical damage indicator malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α), and the main heat stress protein, HSP70,in the plasma and serum were investigated in control (non-parachuting) and parachuting paratroops. Result Significantly higher levels of serum hormones such as growth hormone, insulin, angiotonin I, renin activities, as well as MDA and plasma TNF-α and HSP70 were observed in the parachuting group. Conclusion Whether these changes can potentially serve as useful biomarkers to assess possible abnormal stress in parachutists and to evaluate the health condition and to select parachutists remains to be further studied.