Effect of dexmedetomidine on apoptosis and CHOP in hypoxia/reoxygenation injury A549 cell / 中国应用生理学杂志

OBJECTIVES@#To investigate the effects of dexmedetomidine (Dex) on injury of A549 cells induced by hypoxia/reoxygenation(H/R)and the influence of C/EBP homologous protein (CHOP) expression.@*METHODS@#Logarithmic growth phase A549 cells(it originated from alveolar type Ⅱ epithelial cell line) were randomly divided into 4 groups (=10):normoxic control group (N), Dex group (D), hypoxia/reoxygenation group (H), hypoxia/reoxygenation + Dex group(HD). At the beginning of modeling, 1 nmol/L Dex was puted into D and HD groups. N and D groups were cultured in the normoxic incubator for 30 h. H and HD group were incubated in the anoxic cultivation for 6 h, fo llowed by normoxic culture for 24 h. Then A549 cells were observed under the inverted microscope to observe the morphological changes. Cell activity was detected by cell counting Kit-8(CCK-8) and the apoptosis index(AI) was detected by in situ end labeling (TUNEL) method. The expression of CHOP、glucose-regulated protein of molecular weight 78 kDa (Grp78)、cysteinyl aspirate-specificprotease-3 (caspase-3) protein and CHOP、Grp78 mRNA were detected by Western blot and RT-PCR.@*RESULTS@#Compared with N group, the number of adherent cells in H group decreased significantly, and cell morphology changed. The absorbance value in H group decreased obviously (<0. 01). The AI value and expression of CHOP, Grp78, caspase-3 proteins and CHOP, Grp78 mRNA were significantly increased (<0.01). Compared with H group, the cell damage in HD group was decreased, the absorbance value increased (<0.01), the number of apoptosis cells decreased relatively (<0.01), the expression of CHOP, caspase-3 protein and CHOP mRNA decreased (<0. 01).@*CONCLUSIONS@#Dex has notable effects against H/R injury, which may be related to effective inhibition of apoptosis mediated by the CHOP's signal path.

Effects of dexmedetomidine on hypoxia/reoxygenation injury-induced cell apoptosis and caspase-12 expression in A549 cells / 生理学报

To investigate the effects of dexmedetomidine (DEX) on hypoxia/reoxygenation (H/R) injury-induced cell apoptosis and caspase-12 expression, A549 cells were randomly divided into 4 groups: control group, DEX group, H/R group and DEX+H/R group. Cells of control and DEX groups were cultured in the normoxic incubator for 30 h. Cells of H/R and DEX+ H/R groups were incubated in the anoxic cultivation for 6 h, followed by normoxic culture for 24 h, and DEX (1 nmol/L) was added into the culture medium in DEX and DEX+H/R groups. Morphological changes were observed under the inverted microscope. Cell viability was detected by CCK-8. The apoptosis index (AI) of A549 cells was detected by TUNEL method. The activity of caspase-3 enzyme in cells was detected by using caspase-3 kit. The expressions of GRP78, caspase-12 protein and mRNA were determined by Western blot and RT-PCR respectively. Compared with control group, the morphological changes of the cultured cells were observed: some of the cell fusion occurred and the shape of the cells was multilateral; the cell viability was decreased significantly (P < 0.01), the number of apoptotic cells and the AI value, caspase-3 activity, and the expressions of GRP78, caspase-12 protein/mRNA were significantly increased (P < 0.01) in H/R group. While the administration of DEX alleviated the H/R injury-induced cell damage, obviously increased the cell viability (P < 0.01), significantly decreased the increment of apoptotic cells and the AI value induced by H/R injury (P < 0.01), and also dramatically decreased the H/R injury-induced high level of caspase-3 activity (P < 0.01) as well as high expression of caspase-12 protein and mRNA (P < 0.01). Taken together, the results suggest that DEX can effectively protect A549 cells from the H/R injury, which may be mediated by down-regulating the expression of caspase-12 and inhibiting cell apoptosis.

The effects of ACEI on calpain-mediated cardiomyocytes apoptosis and cardiac function in diabetic rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effects of angiotensin converting enzyme inhibitor (ACEI) captopril on Calpain-mediated cardiomyocytes apoptosis and cardiac function in diabetic rats.</p><p><b>METHODS</b>Thirty adult male SD rats were randomly divided into 3 groups (n = 10), normal control group (NC group), diabetes mellitus group (DM group)and captopril treated group (Cap group). Streptozocin (STZ) were used to make the model of diabetes mellitus, captopril was administrated by gavage at the dose of 50 mg/kg every day, while in NC group and DM group the same volume of normal saline was administrated. Twelve weeks later, left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVDEP), maximal rise rate of left ventricular pressure (+ dp/dtmax) and maximal fall rate of left ventricular pressure (- dp/dtmax) were detected; Western blot was used to detect the expression of Calpain-1 Calpain-2, Bcl-2, Bax and total Caspase3 protein; apoptosis index (AI) were assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL).</p><p><b>RESULTS</b>Compared with NC group, LVDEP was significantly higher; LVSP, + dp/dtmax and - dp/dtmax were significantly decreased (P < 0.05); Bcl-2 protein expression was decreased; the expression of Calpain-1, Calpain-2, Bax and total Caspase3 protein were increased; the value of AI was significantly increased. Compared with DM group, LVDEP was significantly lower; LVSP, + dp/dtmax and - dp/dtmax were significantly increased (P < 0.05); Bcl-2 protein expression was increased, the expression of Calpain-1, Calpain-2, Bax and total Caspase3 protein were decreased; the value of AI was significantly decreased (P < 0.05).</p><p><b>CONCLUSION</b>Captopril can protect diabetic myocardial structure through inhibiting activation of Calpain-1 and Calpain-2, up-regulating the expression of Bcl-2, down-regulating the expression of Bax to inhibit Caspase3 dependent apoptosis, thereby improving the ventricular function and myocardial structure.</p>

Protective effects and mechanism of SP600125 on lung ischemia/reperfusion injury in rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the protective effects and mechanism of SP600125-specificity inhibitor of c-Jun N-terminal kinase (JNK)on lung ischemia /reperfusion injury in rats.</p><p><b>METHODS</b>The unilateral lung ischemia/reperfusion model was replicated in vivo. Rats were randomly divided into three groups (n = 10): control group, ischemia/reperfusion group ( I/R group) and ischemia/reperfusion + SP600125 group (SP600125 group). The lung tissues sampled at the end of each experiment were assayed for wet/dry weight ratio (W/D),the injured alveoli rate (IAR), the expression of phosphorylation JNK (p-JNK) and JNK protein were detected by Western blot, the expression of Bcl-2, Bax, Caspase3 protein were detected by immunocytochemistry techniques, the pneumocyte apoptosis index (AI) was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end abeling(TUNEL), the ultrastructure changes were observed under electron microscope.</p><p><b>RESULTS</b>Compared to I/R group, the expression of p-JNK, Bcl-2, Bax and caspase-3 protein were markedly decreased (all P < 0.01), the expression of Bcl-2 protein and the ratio of Bcl-2/Bax were markedly increased in SP600125 group(all P < 0.01). The value of AI, W/D, IAR showed significantly lower than those in I/R group (all P <0.01). Meanwhile, light morphological and ultrastructure injury were found in SP600125 group.</p><p><b>CONCLUSION</b>SP600125 can suppress JNK signal pathway, up-regulate the ratio of Bcl-2/Bax to inhibit Caspase-3 dependent apoptosis, so that it protects lung tissue from ischemia/reperfusion injury.</p>

Effects of Panax notoginseng saponins on pneumocyte apoptosis and c-Jun N-terminal kinase in lung ischemia/reperfusion injury / 生理学报

The aim of the present study is to investigate the effects of Panax notoginseng saponins (PNS) on pneumocyte apoptosis and apoptosis-related protein, as well as c-Jun N-terminal kinase (JNK) in lung ischemia/reperfusion (I/R) injury. Thirty Wistar rats were randomly divided into control group, I/R group and PNS group. The unilateral lung I/R model was replicated by obstruction of left lung hilus for 30 min and reperfusion for 120 min in vivo. The rats in PNS group were given intraperitoneal injection of PNS at 60 min before ischemia and 10 min before reperfusion. Some lung tissues sampled at the end of the experiment were assayed for wet/dry weight ratio (W/T). The expressions of phosphorylated JNK (p-JNK) and JNK protein were detected by Western blot. The expressions of Bcl-2, Bax and Caspase-3 protein were detected by immunocytochemistry techniques. The pneumocyte apoptotic index (AI) was detected by terminal deoxynuleotidy1 transferase mediated dUTP nick end labeling (TUNEL). The morphological and ultrastructure changes were observed under light microscope and electron microscope, and the injured alveolus rate (IAR) was counted as well. The results showed that compared to control group, I/R group showed increased expressions of p-JNK, Bcl-2, Bax and Caspase-3 protein (all P < 0.01), decreased ratio of Bcl-2/Bax (P < 0.05), and increased values of AI, W/T and IAR (all P < 0.01). Moreover, light microscope and electron microscope showed serious morphological and ultrastructure injury in I/R group. Compared to I/R group, PNS group showed markedly decreased expressions of p-JNK, Bax and Caspase-3 protein (all P < 0.01), increased expression of Bcl-2 protein and ratio of Bcl-2/Bax (both P < 0.01), and lower values of AI, W/T and IAR (all P < 0.01). Meanwhile, light morphological and ultrastructure injury was found to be alleviated in PNS group. These results suggest that PNS can protect lung tissue from I/R injury, and the mechanism may correlate with suppressing JNK signal pathway, up-regulating the ratio of Bcl-2/Bax which results in inhibition of Caspase-3 dependent apoptosis.

Effect of Shenmai injection on expression and activity of heme oxygenase-1 in reperfusion injury after pulmonary ischemia in rabbits / 中国中药杂志

<p><b>OBJECTIVE</b>To explore the effect of Shenmai injection the expression of heme oxygenase-1 (HO-1) in rabbits with reperfusion injury after pulmonary ischemia.</p><p><b>METHOD</b>Single lung ischemia/reperfusion injury animal model was used in vivo. Twenty rabbits were randomly divided into two groups (n = 10, in each), pulmonary ischemia and reperfusion injury (PIRI) group and I-R + Shenmai injection group. The tissue slides were stained by in situ hybridization (ISH) for HO-1 to detect the expression of HO-1 in lung and to analyze the absorbance. Wet to dry ratio of lung tissue weight (W/D) and the injured alveoli rate (IAR) were measured at 180 minutes after lung reperfusion. Meanwhile the lung tissue slide was prepared for electron microscopic observation at 180 minutes after reperfusion.</p><p><b>RESULT</b>HO-1 expression was upregulated in two groups in the pulmonary endothelial cells, part of pulmonary vascular smooth muscle cells, extima of vessels and epithelial cells of airway, the absorbance was 0.148 +/- 0.013, 0.158 +/- 0.012, respectively. The Shenmai injection group showed higher absorbance than those of the IRI group (P < 0.01), lower W/D and IAR values than those of the IRI group (P < 0.01) significantly and lighter abnormal changes of the lung tissue in morphologically than those of the PIRI group.</p><p><b>CONCLUSION</b>Shenmai injection possesses notable protective effects on PIRI in rabbits by increasing the expression of HO-1 in lung.</p>