The effects of Sestrin2 on apoptosis of heat-exposed lung epithelial cells and its mechanism / 中国应用生理学杂志

OBJECTIVE@#To investigate the protective effects of Sestrin2 protein on lung epithelial Beas-2B cells in the heat-exposure environment and its mechanism.@*METHODS@#Lung epithelial Beas-2B cells were cultured at 37℃, 39℃, 40℃ and 41℃ respectively. Cells were harvested at different times (0, 3, 6 and 12 h) after pancreatin digestion. The expressions of Sestrin2, superoxide dismutase(SOD), reactive oxygen species(ROS), cell mitochondrial membrane potential and apoptosis rate of cells were detected by Western blot, fluorescence spectrophotometer and flow cytometry, respectively. Gene expression sequence was cloned into high expression plasmid pcDNA3.1. Beas-2B cells were transfected by Lipfectamine 2000 to construct Sestrin2 and SOD high expression cells. The changes of mitochondrial membrane potential and cell apoptosis were observed in the Sestrin2 and SOD high expression cells.@*RESULTS@#With the increase of temperature, the expression level of Sestrin2 protein in heat treatment group was decreased compared with the control group. When Beas-2B cells were exposed to 41℃, the ROS level was increased, mitochondrial membrane potential was decreased significantly and apoptosis rate was increased at different time points. After high expression of Sestrin2 and SOD in the Beas-2B cells, the expression level of ROS was decreased and the change tendency of mitochondrial membrane potential was decreased, and the apoptosis rate was reduced at 41℃ exposure.@*CONCLUSION@#Sestrin2 can alleviate the apoptosis of lung epithelial cells induced by heat exposure through mitochondrial membrane potential and SOD, which has protective effect on lung epithelial Beas-2B cells.

Effects of soybean isoflavones on the energy metabolism of swimming mice / 中国应用生理学杂志

OBJECTIVE@#To establish an animal model for loaded swimming, so as to investigate the energy metabolism effects of soybean isoflavones (SI) on swimming mice.@*METHODS@#Thirty male Kunming mice were randomly divided into three groups:normal control, swimming group, and swimming+SI group. The normal control group mice were fed a basic AIN-93M diet, the SI groups were supplied with soybean isoflavones(4 g/kg).Two weeks later, the mice were forced to swim for an hour,and then all the mice were killed, the samples of blood, liver and muscles of hind were collected.The serum contents of lactic acid(Lac), the activities of lactic dehydrogenase (LDH), succinate dehydrogenase (SDH), creatine kinase (CK) and ATPase were measured.@*RESULTS@#Compared with normal control,the serum content of Lac was significantly improved in the group of the swimming control and SI(<0.05),the activity of LDH in the serum was obviously improved in the group of the swimming control and SI, and the activity of CK and SDH were both significantly improved in the group of the swimming control and SI except the activity of SDH in the liver of the group SI; compared with the swimming control,the serum contents of Lac,the activities of LDH, ATPase, SDH, CK were obviously improved(<0.05).@*CONCLUSIONS@#Soybean isoflavones can improve the energy metabolism,antioxidant capacity of the swimming mice.

Effect of cadmium on mitochondrial function of hematopoietic stem cells in mouse bone marrow / 军事医学

Objective To explore the effect of cadmium chloride on mitochondrial function of hematopoietic stem cells in mouse bone marrow .Methods After being quarantined for one week , male Kunming mice weighted 20 ±2 g were randomly divided into three groups: control group , low dose cadmium-exposure group and high dose cadmium-exposure group.Mice in low dose and high dose cadmium-exposure groups were exposed to cadmium chloride solution at a dose of 7.5, 15 mg/kg body mass while those in control group were given an equal volume of distilled water through gavage administration every Monday , Wednesday and Friday for six consecutive weeks before cells in mouse bone marrow were collected at the 8th week.Mitochondrial membrane potential and ROS levels of mouse hematopoietic stem cells were detected using a flow cytometry .Results Compared with control group , the gain of body weight was significantly suppressed in cadmium-exposure group (P<0.01).Compared with control group, mitochondrial ROS levels of hematopoietic stem cells significantly increased in cadmium-exposure group and was dose-related(P<0.05,P<0.01). Besides, mitochondrial membrane potential of hematopoietic stem cells decreased in cadmium -exposure group compared with control group and was dose-related(P<0.05,P<0.01).Conclusion Cadmium exposure can lead to dose-related mitochondrial dysfunction of hematopoietic stem cells via oxidative damage in Kunming mice .

The physiological effects of resveratrol and its potential application in high altitude medicine / 中国应用生理学杂志

Resveratrol, as a natural polyphenolic compound, has a wide range of beneficial effects, which includes anti-tumor, cardiovascular protection, anti-oxidant and estrogen-like effects, and so on. Its various physiological properties are closely related to the therapeutic principle for prevention and treatment of high altitude hypoxia injury. Resveratrol may play an important role in relieving or curing high altitude diseases, especially high altitude polycythemia(HAPC). However, the literature about study and application of resveratrol in plateau medicine field is rarely reported up to now. In this review, we summarized the physiological effects of resveratrol, discussed the possible main principle of resveratrol for HAPC therapy, and looked forward to resveratrol's perspective or potential application in high altitude medicine.

A rat model of high altitude polycythemia rapidly established by hypobaric hypoxia exposure / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effects of simple hypobaric hypoxia on parameters of hematology and blood rheology in order to establish a rat model of simulated high altitude polycythemia (HAPC) for the study of pathophysiologic mechanisms and medical prevention and treatment of HAPC.</p><p><b>METHODS</b>Forty-eight male Wistar rats were randomly divided into three normal control groups and three hypoxia model groups. Normal control group rats were bred in normoxia conditions, and hypoxia group rats were subjected to hypoxic exposure for 8 hours per day at simulated 5 500 m high altitude in a hypobaric chamber. After hypoxic exposure for 2, 4, 12 weeks, one group of normal control and hypoxia model rats were killed and blood was collected, respectively. Then parameters of erythrocyte and blood rheology were examined.</p><p><b>RESULTS</b>Mucous membrane of hypoxia model rats showed obviously cyanosis after 2 weeks hypoxic exposure. Hemoglobin concentration of hypoxia model rats were beyond 210 g/L after 2 weeks, 4 weeks and 12 weeks hypoxia exposure and significantly increased than that of normal control rats respectively. Besides, RBC counts, hematocrit, whole blood viscosity, erythrocyte aggregation index of hypoxia model rats were all notably higher than those of normal control rats respectively.</p><p><b>CONCLUSION</b>A rat model of high altitude polycythemia can be rapidly established by hypobaric hypoxia exposure at simulated 5 500 m high altitude for 8 hours daily.</p>

Overexpression of Cdc25C predicts response to radiotherapy and survival in esophageal squamous cell carcinoma patients treated with radiotherapy followed by surgery / 癌症

Biomarker identification is crucial for the selection of patients who might benefit from radiotherapy. To explore potential markers for response and prognosis in patients with locally advanced esophageal carcinoma treated with radiotherapy followed by surgery, we evaluated the expression of cell cycle checkpoint-related proteins Chk2, Cdc25C, and Cyclin D1. A total of 56 patients with locally advanced esophageal squamous cell carcinoma were treated with radiotherapy followed by surgery. Pretreatment tumor biopsy specimens were analyzed for Chk2, Cdc25C, and Cyclin D1 expression by immunohistochemistry. High expression of Chk2, Cyclin D1, and Cdc25C was observed in 44 (78.6%), 15 (26.8%), and 27 (48.2%) patients, respectively. The median survival was 16 months (range, 3-154 months), with a 5-year overall survival rate of 19.6%. Overexpression of Chk2 was associated with smoking (P = 0.021), overexpression of Cdc25C was associated with patient age (P = 0.033) and tumor length (P = 0.001), and overexpression of Cdc25C was associated with pathologic complete response (P = 0.038). Univariate analysis demonstrated that overexpression of Cdc25C and pathologic complete response was associated with better survival. In multivariate analysis, Cdc25C was the most significant independent predictor of better survival (P = 0.014) for patients treated with radiotherapy followed by surgery. Overexpression of Cdc25C was significantly associated with pathologic complete response and better survival of patients with locally advanced esophageal cancer treated with radiotherapy followed by surgery. These results suggest that Cdc25C may be a biomarker of treatment response and good prognosis for esophageal carcinoma patients. Thus, immunohistochemical staining of Cdc25C in a pretreatment specimen may be a useful method of identifying optimal treatment for patients with esophageal carcinoma.

Expression and unique functions of four nuclear factor of activated T cells isoforms in non-small cell lung cancer / 癌症

Nuclear factor of activated T cells (NFAT) is an important family of transcription factors that can be activated by calmodulin and calcineurin in human cells. To investigate the expression and clinical significance of NFAT isoforms and calcineurin in non-small cell lung cancer (NSCLC), we collected tumor and adjacent normal tissues from 159 NSCLC patients and assembled them in a tissue microarray. Protein levels of NFAT1, NFAT2, NFAT3, NFAT4, and calcineurin were determined using immunohistochemistry. Correlations between NFAT and calcineurin expression and clinicopathologic characteristics were analyzed. We found that the positive rates of NFAT1 (52.8%, 84/159), NFAT2 (11.3%, 18/159), NFAT3 (28.3%, 45/159), NFAT4 (47.2%, 75/159), and calcineurin (47.8%, 76/159) expression were significantly higher in tumor tissues than in adjacent normal lung tissues (P<0.001), respectively. The positive rate of NFAT1 expression was significantly higher in patients with adenocarcinoma (63.5%, 47/74) than in those with squamous cell carcinoma (43.5%, 37/85) (χ2=6.340, P=0.012); with lymph node metastasis (61.6%, 53/86) than without lymph node metastasis (42.5%, 31/73) (χ2=5.818, P=0.016); and with stage-II and -III diseases (61.8%, 55/89) than with stage-I disease (41.4%, 29/70) (χ2=6.524, P=0.011). Moreover, the overexpression of NFAT1 was associated with poor survival of NSCLC patients (χ2=5.006, P=0.025). The positive rate of NFAT4 was significantly higher in patients with squamous carcinoma (57.6%, 49/85) than in those with adenocarcinoma (35.1%, 26/74) (χ2=8.045, P=0.005) and with high and moderate differentiation (54.9%, 61/111) than with low differentiation (29.2%, 14/48) (χ2=8.943, P=0.003). Calcineurin overexpression was significantly associated with histologic type (higher in squamous carcinoma than in adenocarcinoma, χ2=8.897, P=0.003), differentiation grade (higher in high-moderation grade than in low grade, χ2=9.566, P=0.002) and gender (higher in male than in female, χ2=5.766, P=0.016). Furthermore, calcineurin expression was significantly correlated with NFAT4 level (r=0.429, P<0.001). These results suggest that NFAT1 expression is associated with lung adenocarcinoma progression, and NFAT4 expression, which was higher in squamous lung cancer, is associated with calcineurin expression and differentiation grade.

Expression of coxsackievirus and adenovirus receptor in non-small cell lung cancer and its significance / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the mRNA and proten expression of coxsackievirus and adenovirus receptor (CAR) in the corresponding normal lung tissue, para-neoplastic tissue and lung cancer tissue, and the correlation of CAR expression with the carcinogenesis as well as the expression difference in various clinicopathologic parameters.</p><p><b>METHODS</b>The expression of CAR mRNA and protein in the samples from 32 lung cancer patients was determined by RT-PCR and Western blot, respectively.</p><p><b>RESULTS</b>The expression level of CAR mRNA and protein in normal lung tissue, paraneoplastic tissue and cancer tissue were 1.000 +/- 0.012, 1.048 +/- 0.035, 1.282 +/- 0.072, and 0.902 +/- 0.038, 0.944 +/- 0.042, 1.08 +/- 0.052, respectively, with a statistical significance among the groups (P = 0.022, P = 0.007, P = 0.009, P = 0.027). There was a statistically significant positive correlation between expression of CAR mRNA and that of CAR protein (r = 0.448, P = 0.026). The expression levels of CAR were significantly different among different pathological types (P = 0.012), with a high level of CAR in all 7 bronchiolo-alveolar carcinoma (BAC, P = 0.029). However, there was no statistical significance in other clinicopathologic parameters (P > 0.05), including gender, age, smoking or not, tumor size, with or without lymph node metastasis and TNM stage.</p><p><b>CONCLUSION</b>The expression of CAR mRNA and protein in cancer tissue samples are significantly higher than that in the normal and paraneoplastic samples, indicating that CAR might play a crucial role in the carcinogenesis. It may become a new potential prognostic marker for lung cancer patients.</p>

Expression of p16 and nm23 genes in salivary gland tumors / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the expression of p16 and nm23 genes in salivary gland tumors and the relation of P16 and nm23 proteins with fumorigenesis of salivary gland tumors.</p><p><b>METHODS</b>Expression of P16 and nm23 proteins was examined by SABC immunohistochemical method in 39 cases of paraffin blocks of normal salivary gland tissues and salivary gland tumors.</p><p><b>RESULTS</b>P16 and nm23 protein positive staining were mainly found in the cytoplasm and cytoblast of all salivary gland tissues. Positive rate of P16 protein expression was 76.9% (10/13) and 40.9% (9/22) in benign and malignant salivary gland tumors, respectively. There was significant difference between P16 protein expression of benign and malignant tumors by chi 2 test (P < 0.05). mm23 protein positive staining was found in 84.6% (11/13) and 45.5% (10/22) of benign and malignant tumors respectively. The expression of nm23 protein in benign and malignant tumors was significantly different (P < 0.05). There was no correlation of the expression of P16 and nm23 in salivary gland tumors was found (P > 0.05).</p><p><b>CONCLUSION</b>p16 and nm23 genes may play an important role in different sides in salivary gland tumorigenesis and the reduce of the expression of p16 and nm23 genes may contribute to the generation of malignant salivary gland tumors.</p>