Angiotensin II ; pharmacology ; Calcium ; metabolism ; Cell Hypoxia ; drug effects ; physiology ; Cells, Cultured ; Endothelial Cells ; drug effects ; metabolism ; physiology ; Humans ; Membrane Potential, Mitochondrial ; drug effects ; physiology ; Oxygen ; metabolism

PURPOSE: To investigate the effects of brimonidine, an alpha-2-adrenergic agonist, on barrier function in ARPE-19 cells by measuring transepithelial resistance (TER). METHODS: ARPE-19 cells were cultured into a confluent monolayer on a microporous filter. Brimonidine was added to the apical medium, and the barrier function of the cells was evaluated by measuring TER. A subset of cells was treated under hypoxic conditions, and the TER changes observed upon administration of brimonidine were compared to those observed in cells in normoxic conditions. RESULTS: The ARPE cell membrane reached a peak resistance of 29.1+/-7.97 Omega cm2 after four weeks of culture. The TER of the cells treated under normoxic conditions increased with brimonidine treatment; however, the TER of the cells treated under hypoxic conditions did not change following the administration of brimonidine. CONCLUSIONS: Barrier function in ARPE-19 cells increased with brimonidine treatment. Understanding the exact mechanism of this barrier function change requires further investigation.
Adrenergic alpha-Agonists/*pharmacology ; Cell Hypoxia/drug effects/physiology ; Cell Line ; Electric Impedance ; Humans ; Quinoxalines/*pharmacology ; Receptors, Adrenergic, alpha-2/*drug effects ; Retinal Pigment Epithelium/*drug effects/*physiology

OBJECTIVETo study the effect and molecular mechanism of two haw leaf extracts, Vitexin-rhamnoside (VR) and Vitexin-glucoside (VG), and their preparation, Aoshaen injection (AI), on the polymorphonuclear leucocyte (PMN) adhesion during human umbilical vein endothelial cell (HUVEC) anoxia/reoxygenation (A/R) injury.

METHODSThe cell model of A/R injury duplicated by breaking off the oxygen supplying of HUVEC for 60 min followed with reoxygenating for 30 min (phase 1) or 240 min (phase 2) was taken as the experimental objective. The effects of testing drugs (VR, VG and AI) on PMN adhesion in the model cells were measured by enzyme immunoassay, and their effects on PMN superficial adhesion molecule CD11/CD18 expression were measured by flow cytometer respectively.

RESULTSAfter 60 min of anoxia, HUVEC was shrunk and deformed. The adhesion between PMN and HUVEC significantly revealed at phase 1 in the model group, but it was fewer in the normal cell group, and also lesser in the groups treated with various drugs. The condition of cell adhesion revealed at phase 2 was the similar to that at phase 1. All testing drugs, VR, VG and AI, showed inhibitory effect on the cell adhesion at either phase 1 or phase 2, showing a certain dose-effect relationship. The expression of CD11/ CD18 was also inhibited by the testing drugs, and a good dose-effect relation was shown by VG and AI.

CONCLUSIONAt the resting condition, there are almost no expression of CD11/CD18 molecule, but it could be enhanced by incubating PMN with supernate of A/R injured HUVEC culture, and more marked at phase 1. Adding the test drugs into the supernate could inhibit the enhancing of CD11/CD18 molecule expression and reduce the PMN-HUVEC adhesion, which may be one of the molecular mechanisms of haw leaf extracts and their preparation in protecting heart against A/R injury.

Cell Adhesion ; drug effects ; Cell Hypoxia ; drug effects ; Cells, Cultured ; Crataegus ; chemistry ; Female ; Humans ; Hypoxia ; drug therapy ; physiopathology ; Neutrophils ; drug effects ; physiology ; Oxygen ; metabolism ; Plant Extracts ; pharmacology ; Plant Leaves ; chemistry ; Pregnancy ; Umbilical Veins ; cytology ; drug effects

To give an overview of contemporary experimental research using Chinese medicine (CM) for the treatment of cancer. As an integral part of mainstream medicine in the People's Republic of China, CM emphasizes improvements in holistic physical condition instead of merely killing tumor cells, which is consistent with the current medical model that advocates patient-oriented treatment. Great progress has been made in experimental research, and the principle aspects include anti-tumor angiogenesis, inducing apoptosis and differentiation, reversing multidrug resistance, and improving immune function. As a current hot topic in cancer research, tumor microenvironment (TME) highlights the mutual and interdependent interaction between tumor cells and their surrounding tissues, and the CM treatment concept bears a striking resemblance to it. To date, primary points of TME include extracellular matrix remodeling, inflammation, hypoxia, and angiogenesis, but trials using CM with a focus on TME are rare. Despite considerable recent development, experimental research on CM for solving cancer issues appears insufficient. Greater efforts in this field are urgently needed.
Apoptosis ; drug effects ; Autophagy ; drug effects ; Cell Differentiation ; drug effects ; Cell Hypoxia ; drug effects ; Drug Resistance, Multiple ; drug effects ; Immunomodulation ; Inflammation Mediators ; pharmacology ; Medicine, Chinese Traditional ; Neoplasms, Experimental ; Research ; Tumor Microenvironment ; drug effects ; physiology

OBJECTIVETo study the effects of hypoxia of different duration on movement and proliferation of human epidermal cell line HaCaT.

METHODS(1) HaCaT cells in logarithmic phase were cultured in RPMI 1640 medium containing 10% FBS (the same culture method below). Cells were divided into control group (routine culture) and hypoxia for 1, 3, 6 h groups according to the random number table (the same grouping method below), with 6 wells in each group. Cells in the 3 hypoxia groups were cultured in incubator containing 5% CO2, 2% O2, and 93% N2 (the same hypoxic condition below) for corresponding duration. Range of movement of cells in 3 hours was observed under live cell imaging workstation, and their curvilinear and rectilinear movement speeds were calculated at post observation hour (POH) 1, 2, 3. (2) HaCaT cells in logarithmic phase were divided into control group (routine culture) and hypoxia for 1, 3, 6, 9, 12, 24 h groups, with 20 wells in each group. Cells in the 6 hypoxia groups were cultured under hypoxic condition for corresponding duration. Proliferation of cells was examined with cell counting kit and microplate reader (denoted as absorbance value). (3) HaCaT cells in logarithmic phase were divided into control group (routine culture) and hypoxia for 1, 3, 6, 24 h groups, with 5 wells in each group. Cells in the 4 hypoxia groups were cultured under hypoxic condition for corresponding duration. Protein expression of proliferating cell nuclear antigen (PCNA) was determined with Western blotting. Data were processed with one-way analysis of variance and Dunnett- t test.

RESULTS(1) Compared with that of control group, the movement area of cells was obviously expanded in hypoxia for 1, 3, 6 h groups. The longer the hypoxic treatment, the greater the increase was. At POH 1, 2, 3, the curvilinear movement speeds of cells in hypoxia for 1, 3, 6 h groups were respectively (43 ± 18), (44 ± 17), (43 ± 16) µm/h; (44 ± 16), (44 ± 14), (45 ± 14) µm/h; (55 ± 19), (54 ± 17), (56 ± 18) µm/h. They were significantly higher than those of control group [(33 ± 13), (33 ± 12), (33 ± 10) µm/h, with t values from 2.840 to 9.330, P < 0.05 or P < 0.01]. The curvilinear movement speed of cells was significantly higher in hypoxia for 6 h group than in hypoxia for 1 or 3 h group (with t values from 3.474 to 4.545, P < 0.05 or P < 0.01). There was no significant difference in the curvilinear movement speed among the observation time points within each group (with F values from 0.012 to 0.195, P values above 0.05). At POH 1, the rectilinear movement speed of cells in hypoxia for 1 h group was (22 ± 11) µm/h, which was obviously higher than that of control group [(15 ± 10) µm/h, t = 2.697, P < 0.01]. At POH 1, 2, 3, rectilinear movement speeds of cells in hypoxia for 3 and 6 h groups were respectively (19 ± 14), (12 ± 8), (10 ± 6) µm/h; (32 ± 19), (21 ± 13), (17 ± 12) µm/h. They were significantly higher than those of control group [(9 ± 7) and (6 ± 5) µm/h at POH 2 and 3, with t values from 1.990 to 8.231, P < 0.05 or P < 0.01]. The rectilinear movement speed of cells in hypoxia for 6 h group was obviously higher than that of hypoxia for 1 or 3 h group (with t values from 3.394 to 6.008, P < 0.05 or P < 0.01). The rectilinear movement speed of cells in each group decreased at POH 2 or 3 in comparison with POH 1 (with t values from -8.208 to -4.232, P values below 0.01). The rectilinear movement speed of cells in control group at POH 3 was significantly different from that at POH 2 (t = -1.967, P < 0.05). (2) The proliferation levels of cells in control group and hypoxia for 1, 3, 6, 9, 12, 24 h groups were respectively 1.11 ± 0.08, 1.36 ± 0.10, 1.39 ± 0.05, 1.38 ± 0.05, 1.10 ± 0.14, 1.06 ± 0.09, 0.99 ± 0.06 (F = 39.19, P < 0.01). Compared with that of control group, the rate of proliferation of cells was obviously increased in hypoxia for 1, 3, 6 h groups (with t values respectively 6.639, 7.403, 7.195, P values below 0.01), but obviously decreased in hypoxia for 24 h group (t = -3.136, P < 0.05). The proliferation of cells decreased in hypoxia for 9, 12, 24 h groups in comparison with hypoxia for 1, 3, 6 h groups (with t values from -10.538 to -6.775, P values below 0.01). (3) The protein expressions of PCNA of cells in control group and hypoxia for 1, 3, 6, 24 h groups were respectively 0.93 ± 0.12, 0.97 ± 0.14, 1.62 ± 0.18, 0.95 ± 0.09, 0.66 ± 0.21 (F = 20.11, P < 0.01). Compared with that of control group, the expression of PCNA was obviously increased in hypoxia for 1, 3, 6 h groups (with t values respectively 2.339, 5.783, 2.235, P < 0.05 or P < 0.01), but obviously decreased in hypoxia for 24 h group (t = -1.998, P < 0.05). The protein expression of PCNA was higher in hypoxia for 3 h group than in hypoxia for 1 or 6 h group (with t values respectively 4.312 and 3.947, P values below 0.01), and it was increased in the 3 groups in comparison with that of hypoxia for 24 h group (with t values respectively 2.011, 6.193, 3.287, P < 0.05 or P < 0.01).

CONCLUSIONSShort-time hypoxia (1, 3, 6 h) treatment can promote the movement and proliferation of HaCaT cells. Hypoxia for 6 h is the best condition to promote their movement, while hypoxia for 3 or 6 h is better for their proliferation.

Carbon Dioxide ; pharmacology ; Cell Cycle ; drug effects ; Cell Line ; Cell Movement ; physiology ; Cell Proliferation ; drug effects ; physiology ; Cells, Cultured ; Epithelial Cells ; cytology ; drug effects ; Humans ; Hypoxia ; physiopathology ; Nitric Oxide ; pharmacology ; Oxygen ; pharmacology ; Phosphorylation ; Proliferating Cell Nuclear Antigen ; Signal Transduction

OBJECTIVETo investigate the effect of telomerase activation on biological behaviors of neural stem cells after hypoxic-ischemic insults.

METHODSThe neural stem cells passaged in vitro were divided into four groups: control, oxygen-glucose deprivation (OGD), OGD+cycloastragenol (CAG) high concentration (final concentration of 25 μM), and OGD+CAG low concentration (final concentration of 10 μM). The latter three groups were subjected to OGD. Telomerase reverse transcriptase (TERT) expression level was evaluated by Western blot. Telomerase activity was detected by telomerase repeat amplification protocol (TRAP). Cell number and neural sphere diameter were measured under a microscope. The activity of lactate dehydrogenase (LDH) was examined by chemiluminescence. Cell proliferation rate and apoptosis were detected by flow cytometry.

RESULTSAfter OGD insults, obvious injury of neural stem cells was observed, including less cell number, smaller neural sphere, more dead cells, lower proliferation rate and decreased survival rate. In CAG-treated groups, there were higher TERT expression level and telomerase activity compared with the control group (P<0.05). In comparison with the OGD group, CAG treatment attenuated cell loss (P<0.05) and neural sphere diameter decrease (P<0.05), promoted cell proliferation (P<0.05), and increased cell survival rate (P<0.05). Low and high concentrations of CAG had similar effects on proliferation and survival of neural stem cells (P>0.05). In the normal cultural condition, CAG treatment also enhanced TERT expression (P<0.05) and increased cell numbers (P<0.05) and neural sphere diameter (P<0.05) compared with the control group.

CONCLUSIONSTelomerase activation can promote the proliferation and improve survival of neural stem cells under the state of hypoxic-ischemic insults, suggesting telomerase activators might be potential agents for the therapy of hypoxic-ischemic brain injury.

Animals ; Cell Survival ; drug effects ; Enzyme Activation ; Hypoxia-Ischemia, Brain ; etiology ; Neural Stem Cells ; drug effects ; physiology ; Rats ; Sapogenins ; pharmacology ; Telomerase ; physiology

BACKGROUNDRetinal degenerative diseases are the leading causes of blindness in developed world. Retinal progenitor cells (RPCs) play a key role in retina restoration. Triamcinolone acetonide (TA) is widely used for the treatment of retinal degenerative diseases. In this study, we investigated the role of TA on RPCs in hypoxia condition.

METHODSRPCs were primary cultured and identified by immunofluorescence staining. Cells were cultured under normoxia, hypoxia 6 h, and hypoxia 6 h with TA treatment conditions. For the TA treatment groups, after being cultured under hypoxia condition for 6 h, RPCs were treated with different concentrations of TA for 48-72 h. Cell viability was measured by cell counting kit-8 (CCK-8) assay. Cell cycle was detected by flow cytometry. Western blotting was employed to examine the expression of cyclin D1, Akt, p-Akt, nuclear factor (NF)-κB p65, and caspase-3.

RESULTSCCK-8 assays indicated that the viability of RPCs treated with 0.01 mg/ml TA in hypoxia group was improved after 48 h, comparing with control group (P < 0.05). After 72 h, the cell viability was enhanced in both 0.01 mg/ml and 0.02 mg/ml TA groups compared with control group (all P < 0.05). Flow cytometry revealed that there were more cells in S-phase in hypoxia 6 h group than in normoxia control group (P < 0.05). RPCs in S and G2/M phases decreased in groups given TA, comparing with other groups (all P < 0.05). There was no significant difference in the total Akt protein expression among different groups, whereas upregulation of p-Akt and NF-κB p65 protein expression and downregulation of caspase-3 and cyclin D1 protein expression were observed in 0.01 mg/ml TA group, comparing with hypoxia 6 h group and control group (all P < 0.05).

CONCLUSIONLow-dose TA has anti-apoptosis effect on RPCs while it has no stimulatory effect on cell proliferation.

Animals ; Apoptosis ; drug effects ; physiology ; Caspase 3 ; metabolism ; Cell Cycle ; drug effects ; physiology ; Cell Hypoxia ; drug effects ; physiology ; Cell Proliferation ; drug effects ; physiology ; Cell Survival ; drug effects ; physiology ; Cells, Cultured ; Cyclin D1 ; metabolism ; NF-kappa B ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Rats, Sprague-Dawley ; Retina ; cytology ; Stem Cells ; cytology ; drug effects ; Triamcinolone Acetonide ; pharmacology

To discuss the effect of puerarin (Pue) on the proliferation of hypoxia-induced pulmonary artery smooth muscle cells (PASMCs) and discuss whether its mechanism is achieved by regulating reactive oxygen. PASMCs of primarily cultured rats (2-5 generations) were selected in the experiment. MTT, Western blot, FCM and DCFH-DA were used to observe Pue's effect the proliferation of PASMCs. The Western blot was adopted to detect whether ROS participated in Pue's effect in inhibiting PASMC proliferation. The PASMCs were divided into five groups: the normoxia group, the hypoxia group, the hypoxia + Pue group, the hypoxia + Pue + Rotenone group and the hypoxia + Rotenone group, with Rotenone as the ROS blocker. According to the results, under the conditions of normoxia, Pue had no effect on the PASMC proliferation; But, under the conditions of hypoxia, it could inhibit the PASMC proliferation; Under the conditions of normoxia and hypoxia, Pue had no effect on the expression of the tumor necrosis factor-α (TNF-α) among PASMCs, could down-regulate the expression of hypoxia-induced cell cycle protein Cyclin A and proliferative nuclear antigen (PCNA). DCFH-DA proved Pue could reverse ROS rise caused by hypoxia. Both Rotenone and Pue could inhibit the up-regulated expressions of HIF-1α, Cyclin A, PCNA caused by anoxia, with a synergistic effect. The results suggested that Pue could inhibit the hypoxia-induced PASMC proliferation. Its mechanism may be achieved by regulating ROS.
Animals ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Hypoxia ; pathology ; Isoflavones ; pharmacology ; Male ; Myocytes, Smooth Muscle ; drug effects ; physiology ; Proliferating Cell Nuclear Antigen ; analysis ; Pulmonary Artery ; cytology ; drug effects ; Rats ; Rats, Wistar ; Reactive Oxygen Species ; metabolism

OBJECTIVETo investigate the expression of inducible heme oxygenase (HO-1) gene in pulmonary artery smooth muscle cells (PASMCs) exposed to hypoxia, and the influence of carbon monoxide (CO) on the proliferation of PASMCs under hypoxic conditions.

METHODSPrimary culture of rat PASMCs were passed every 3 days, and the 3 - 5 passages were used. After exposure to hypoxic conditions (95% N2, 5% CO(2)) 0, 12, 24 and 48 hours, the level of HO-1 mRNA was examined by reverse transcriptase polymerase chain reaction (RT-PCR). The volume of COHb in the medium was measured spectrophotometrically. The cyclic guanosine mono-phosphate (cGMP) concentration of cell extracts was determined by radioimmunoassay. PASMCs were divided into 5 groups, cultured under normoxia and hypoxia and treated with hemin, hemoglobin (Hb) and exogenous CO respectively. Then 3-(4, 5-cimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) colorimetric assay and immunocytochemical staining were used to study the energy metabolism and the expression of proliferating cell nuclear antigen (PCNA) in PASMCs. Flow cytometry was used to analyze the cell cycle of PASMCs.

RESULTSAfter exposure to hypoxic conditions for 12, 24, and 48 hours, the HO-1 mRNA increased by 2.7%, 5.7% and 27.1% respectively (P < 0.01). The carboxy-hemoglobin (COHb) in the medium increased by 13.8%, 31.0% and 93.1% (P < 0.01); the cGMP concentrations were 2.7, 4.0 and 6.8-fold compared with the control group (P < 0.01 and P < 0.05). In comparison with the control group, the value of MTT colorimetric assay, the immunocytochemical staining of PCNA and the percentages of PASMCs in S and G2M phases in the hypoxic group were significantly higher (P < 0.01). After treatment with Hemin and CO, the results of the above analysis decreased significantly (P < 0.01 and P < 0.05), but increased significantly after treatment with Hb (P < 0.01 and P < 0.05).

CONCLUSIONSThe expression of HO-1 gene in PASMCs is upregulated by hypoxia and the production of endogenous CO is elevated as well. The endogenous CO suppresses the proliferation of PASMC in an autocrine way. Both the induction of endogenous CO by Hemin and the treatment with exogenous CO can suppress the proliferation of rat PASMCs of under hypoxic conditions.

Carbon Monoxide ; pharmacology ; physiology ; Cell Division ; drug effects ; Cells, Cultured ; Gene Expression ; Heme Oxygenase (Decyclizing) ; genetics ; Hypoxia ; pathology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; pathology ; Pulmonary Artery ; pathology

OBJECTIVETo observe the change of the neuropeptide pro-protein processing system in the ischemic retina ganglion cell-5 (RGC-5) cells, pro-protein convertase-2 (PC2), carboxypeptidase-E (CPE) and preproneuropeptide Y (preproNPY) protein levels in the ischemic RGC-5 cells and conditioned medium were analyzed.

METHODSThe RGC-5 cell was differentiated in 0.1 mumol/L staurosporine for 24 h and then stressed by different doses of oxygen and glucose deprivation (OGD). The acute or chronic OGD-induced cell death rates were obtained by using PI or TUNEL staining. The protein expression levels were determined by using the Western blot method and PC2 activity analysis.

RESULTSThe ischemia caused substantial cell death in an OGD dose-dependent manner. In the cells, proPC2 and preproNPY protein levels gradually increased whereas proCPE gradually decreased. After OGD, PC2 activity was decreased. In the conditioned medium, proPC2 and PC2 proteins gradually decreased whereas proCPE, CPE, and preproNPY proteins gradually increased.

CONCLUSIONThese results demonstrated that OGD inhibited the neuropeptide pro-protein processing system by reducing PC2 activity and the maturation of proPC2. The aggregation of the pro-proteins and the increase of the active CPE excision adversely exacerbated the cell injury. The pro-protein processing system might play a critical role in the ischemic stress of RGC-5 cells.

Animals ; Carboxypeptidase H ; metabolism ; Cell Death ; drug effects ; physiology ; Cell Differentiation ; drug effects ; Cell Hypoxia ; drug effects ; physiology ; Cell Line, Transformed ; Enzyme Inhibitors ; pharmacology ; Gene Expression Regulation, Enzymologic ; drug effects ; physiology ; Glucose ; deficiency ; In Situ Nick-End Labeling ; methods ; Indoles ; Neuropeptide Y ; metabolism ; Proprotein Convertase 2 ; metabolism ; Protein Precursors ; metabolism ; Rats ; Retinal Ganglion Cells ; drug effects ; metabolism ; Staurosporine ; pharmacology ; Time Factors