NeiyiKangfu tablets control the progression of endometriosis through inhibiting RAF/MEK/ERK signal pathway by targeting RKIP

BACKGROUND

NeiyiKangfu tablets (NYKF) are widely used clinically for the treatment of endometriosis (EMS), whose mechanism of action has been extensively studied. Researchers have found that NYKF may control the development of ectopic lesions by inhibiting angiogenesis and inflammatory cytokine secretion. Nevertheless, NYKF's mechanism of action remains unclear.

METHODS

In the present study, the function of NYKF in the progression of EMS and the associated underlying mechanism was investigated by in vivo and in vitro experiments. EMS model mice were treated with NYKF and the pro-inflammatory factors and apoptosis of ectopic endometrium as well as RAF/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling activation were assessed. In addition, human endometriosis-derived immortalized entopic stromal (hEM15A) cells transfected with or without RAF kinase inhibitor protein (RKIP)-small-interfering RNA (siRNA) were also treated with NYKF and the proliferation, migration, apoptosis, and RAF/MEK/ERK signaling activation were measured by Cell Counting Kit-8 (CCK-8), flow cytometry, Transwell, and western blot, respectively.

RESULTS

Results showed that NYKF increased the expression of RKIP, inhibited RAF/MEK/ERK signaling activation, and induced apoptosis while inhibiting proliferation and migration both in EMS mice and hEM15A cells. RKIP knockdown could inhibit the effect of NYKF treatment, leading to the activation of RAF/MEK/ERK signaling and the proliferation and migration of hEM15A cells.

CONCLUSIONS

In conclusion, these results suggest that NYKF treatment promotes apoptosis and inhibits proliferation and migration in EMS by inhibiting the RAF/MEK/ERK signaling pathway by targeting RKIP.

[Expression and role of Pim1 in cultured cortical neurons with oxygen-glucose deprivation/reoxygen injury]

OBJECTIVE

To study the expression and effect of Pim1 in primary cortical neurons after hypoxic-ischemic injury.

METHODS

Cortical neurons were isolated from 1-day-old C57BL/6 mice and cultured in neurobasal medium. On the 8th day of neuron culture, cells were subjected to oxygen-glucose deprivation/reoxygen (OGD/R) treatment to mimic in vivo hypoxic injury of neurons. Briefly, medium were changed to DMEM medium, and cells were cultured in 1% O₂ for 3 hours and then changed back to normal medium and conditions. Cells were collected at 0 hour, 6 hours, 12 hours and 24 hours after OGD/R. Primary neurons were transfected with Pim1 overexpression plasmid or mock plasmid, and then were exposed to normal conditions or OGD/R treatment. They were named as Pim1 group, control group, OGD/R group and OGD/R+Pim1 group respectively. Real-time PCR was used to detect Pim1 mRNA expression. Western blot was used to detect the protein expression of Pim1 and apoptotic related protein cleaved caspase 3 (CC3). TUNEL staining was used to detect cell apoptosis.

RESULTS

Real-time PCR and Western blot results showed that Pim1 mRNA and protein were significantly decreased in neurons after OGD/R. They began to decrease at 0 hour after OGD/R, reached to the lowest at 12 hours after OGD/R, and remained at a lower level at 24 hours after OGD/R (P<0.01). Overexpression of Pim1 significantly upregulated the protein level of Pim1. Under OGD/R conditions, the CC3 expression and the apoptosis rate in cells of the Pim1 group were significantly lower than in un-transfected cells (P<0.01).

CONCLUSIONS

Hypoxic-ischemic injury may decrease Pim1 expression in neurons. Overexpressed Pim1 may inhibit apoptosis induced by OGD/R.

[Effect of Fei-Liu-Ping ointment combined with cyclophosphamide on lung cancer cell proliferation and acidic microenvironment]

OBJECTIVE

To observe the effects of Fei-Liu-Ping ointment and chemotherapy on mice with lung cancer, and to explore the inherent mechanism of action from the point of acidic microenvironment and apoptosis.

METHODS

First of all, the Lewis lung cancer transplanted mouse model was established. Therefore, they were treated by Fei-Liu-Ping ointment, cyclophosphamide, Fei-Liu-Ping ointment + cyclophosphamide and the saline as control. All the groups' tumor size, tumor growth rate and food consumption were recorded. The mice were sacrificed and the tumors were took out after 15 days' interventions. Then lactate relative concentrations were detected with lactate kits and the protein expressions of glucose transporter 4 (GLUT4), hexokinase 1 (HK1), glucose-regulated protein 78 (GRP78), carbonic anhydrase-IX (CA-IX) were detected through immunohistochemical staining. Flow cytometry was adopted to detect the percentage of apoptotic tumor cells and regulatory T cells (Treg), and the expression of hypoxia-inducible factor-1α (HIF-1α), Bcl-2, Bax, Caspase-3, interleukin-2 (IL-2) were tested through western blot.

RESULTS

The strongest inhibition effect and the lowest tumor growth rate was found in Fei-Liu-Ping ointment + cyclophosphamide group. There were significant differences between Fei-Liu-Ping ointment + cyclophosphamide group and saline group(P<0.05). And the highest food consumption was found in Fei-Liu-Ping ointment + cyclophosphamide group while there were no significant differences between Fei-Liu-Ping ointment + cyclophosphamide group and saline group (P>0.05). Further molecular biological detections found that the lowest lactate level and regulatory T cells ratio were found in Fei-Liu-Ping ointment + cyclophosphamide group and these expressions of GLUT4, HK1, GRP78, CA-IX were suppressed. There were significant differences between Fei-Liu-Ping ointment+cyclophosphamide group and saline group (P<0.05). In addition, the Fei-Liu-Ping ointment + cyclophosphamide group's cell apoptosis increased significantly compared with saline group and there were significant differences on expressions of HIF-1α, Bcl-2, Bax, Caspase-3, IL-2 for this group compared with saline group.

CONCLUSION

Chemotherapy and Fei-Liu-Ping ointment had the synergistic effect on inhibiting tumor growth and improving the general conditions of tumor-bearing mice. The effect was partly owed to the improvement on tissue hypoxia, the inhibition of HIF-1α expression and the regulations on its downstream proteins, such as GLUT4, HK1, GRP78, and CA-IX. And then all these alterations led to the modulation tumor acidic microenvironment, the induced tumor cells apoptosis and suppression of T cells to regulatory T cells differentiation.

[Effect of irisin on hypoxic-ischemic brain damage in neonatal rats]

OBJECTIVE

To study the effect and mechanism of action of irisin on hypoxic-ischemic brain damage in neonatal rats.

METHODS

A total of 248 7-day-old Sprague-Dawley rats were randomly divided into a sham-operation group, a model group, and low- and high-dose irisin intervention groups (n=62 each). The rats in the model and irisin intervention groups were given hypoxic treatment after right common carotid artery ligation to establish a model of hypoxic-ischemic brain damage. Those in the sham-operation group were given the separation of the right common carotid artery without ligation or hypoxic treatment. The rats in the high- and low-dose irisin intervention groups were given intracerebroventricular injection of recombinant irisin polypeptide at a dose of 0.30 µg and 0.15 µg respectively. Those in the model and sham-operation groups were given the injection of an equal volume of PBS. The water maze test was used to compare neurological behaviors between groups. TTC staining, hematoxylin-eosin staining and TUNEL staining were used to observe histopathological changes of the brain. Western blot was used to measure the expression of the apoptosis-related molecules cleaved-caspase-3 (CC3), BCL-2 and BAX.

RESULTS

Compared with the sham-operation group, the model group had a significant increase in latency time and a significant reduction in the number of platform crossings (P<0.05). Compared with the model group, the high-dose irisin intervention group had a significant reduction in latency time and a significant increase in the number of platform crossings (P<0.05). Compared with the sham-operation group, the model group had massive infarction in the right hemisphere, with significant increases in karyopyknosis and karyorrhexis. Compared with the model group, the high-dose irisin intervention group had a smaller infarct area of the right hemisphere, with reductions in karyopyknosis and karyorrhexis. The model group had a significantly higher apoptosis rate of cells in the right cerebral cortex and the hippocampus than the sham-operation group. The high-dose irisin intervention group had a significantly lower apoptosis rate than the model group (P<0.05). At 24 and 48 hours after modeling, the sham-operation group had a significantly lower level of CC3 than the model group (P<0.05). Compared with the model group, the high-dose irisin intervention group had a significantly lower level of CC3 and a significantly higher BCL-2/BAX ratio (P<0.05). The low-dose irisin intervention group had similar laboratory markers and histopathological changes of the brain to the model group.

CONCLUSIONS

Irisin can alleviate hypoxic-ischemic brain damage in neonatal rats in a dose-dependent manner, possibly by reducing cell apoptosis in the cerebral cortex and the hippocampus.

[Expression of gamma-delta T cells in immune microenvironment in children with Henoch-Schönlein purpura]

OBJECTIVE

To study the role of gamma-delta T (γδ T) cells and its subsets in the immunopathogenesis of Henoch-Schönlein purpura (HSP) in children, and to provide new ideas for the treatment of HSP in children from the aspect of γδ T cell regulation.

METHODS

A total of 33 children with HSP were enrolled as the HSP group, and 21 healthy children were enrolled as the healthy control group. The percentages of γδ T cells and its subsets Vδ1⁺ T and Vδ2⁺ T cells among peripheral blood mononuclear cells (PBMCs) were measured, as well as the apoptosis rate of γδ T cell and plasma level of interleukin-17 (IL-17).

RESULTS

Compared with the healthy control group, the HSP group had significantly lower percentages of lymphocytes in PBMCs and Vδ2⁺ T cells in γδ T cells (P<0.05). The HSP group had significantly higher percentage of Vδ1⁺ T cells in γδ T cells and plasma level of IL-17 than the healthy control group. The HSP group had a significantly higher overall apoptosis rate of γδ T cells than the healthy control group (P<0.05), especially early apoptosis. The percentage of Vδ2⁺ T cells was positively correlated with overall apoptosis rate (r_s=0.615, P<0.05) and was negatively correlated with IL-17 level (r_s=-0.398, P<0.05).

CONCLUSIONS

Vδ1⁺/Vδ2⁺ T cell immune imbalance mediated by γδ T cells and over-activation of IL-17 may be involved in the development of HSP, among which the disturbance of immune tolerance induced by Vδ2⁺ T cells plays an important role in the pathophysiology of the disease.

[Effect and molecular mechanism of interferon-α on podocyte apoptosis induced by hepatitis B virus X protein]

OBJECTIVE

To investigate the effect and molecular mechanism of interferon-α (INF-α) on the apoptosis of the mouse podocyte cell line MPC5 induced by hepatitis B virus X (HBx) protein.

METHODS

MPC5 cells were transfected with the pEX plasmid carrying the HBx gene. RT-PCR was used to measure the mRNA expression of HBx at different time points. MPC5 cells were divided into 4 groups: control group (MPC5 cells cultured under normal conditions), INF-α group (MPC5 cells cultured with INF-α), HBx group (MPC5 cells induced by HBx), and HBx+INF-α group (MPC5 cells induced by HBx and cultured with INF-α). After 48 hours of intervention under different experimental conditions, flow cytometry was used to measure the apoptosis of MPC5 cells, and quantitative real-time PCR and Western blot were used to measure the mRNA and protein expression of slit diaphragm-related proteins (nephrin, CD2AP, and synaptopodin) and the cytoskeleton-related protein transient receptor potential cation channel 6 (TRPC6).

RESULTS

MPC5 cells transfected by pEX-HBx had the highest expression of HBx mRNA at 48 hours after transfection (P<0.05). Compared with the control, INF-α and HBx+INF-α groups, the HBx group had a significant increase in the apoptosis rate of MPC5 cells (P<0.05). Compared with the control and INF-α groups, the HBx group had significant reductions in the mRNA and protein expression of nephrin, synaptopodin, and CD2AP and significant increases in the mRNA and protein expression of TRPC6 (P<0.05). Compared with the HBx group, the HBx+INF-α group had significant increases in the mRNA and protein expression of nephrin, synaptopodin, and CD2AP and significant reductions in the mRNA and protein expression of TRPC6 (P<0.05).

CONCLUSIONS

INF-α can inhibit the apoptosis of podocytes induced by HBx, possibly through improving the abnormal expression of slit diaphragm-related proteins (CD2AP, nephrin, and synaptopodin) and cytoskeleton-related protein (TRPC6) induced by HBx.

[Effect of ultraviolet irradiation on the proliferation of acute promyelocytic leukemia cells under hypoxic conditions and related mechanisms]

OBJECTIVE

To study the effect of 280 nm-LED ultraviolet irradiation on the proliferation of acute promyelocytic leukemia (APL) HL-60 cells under hypoxic conditions and related mechanism.

METHODS

HL-60 cells in the logarithmic growth phase were selected and divided into control, hypoxia, ultraviolet and hypoxia+ultraviolet groups. The cells in the hypoxia group were treated with cobalt chloride (with a final concentration of 150 μmol/L), those in the ultraviolet group were irradiated by 280 nm-LED ultraviolet with an energy intensity of 30 J/m2, and those in the hypoxia+ultraviolet group were treated with cobalt chloride and then irradiated by 280 nm-LED ultraviolet. After 48 hours of treatment, the cells were placed under an invert microscope to observe cell morphology. CCK-8 assay was used to measure the inhibition rate of cell proliferation. Annexin V-FITC/PI double staining flow cytometry was used to evaluate cell apoptosis. Quantitative real-time PCR was used to measure the mRNA expression of Bcl-2. Each experiment above was repeated three times independently.

RESULTS

Compared with the control group, the experimental groups showed shrinkage, decreased brightness, and disordered arrangement of cells, and the number of cells decreased over the time of culture. There were significant differences in the inhibition rate of cell proliferation and cell apoptosis rate among the groups (P<0.01), and the hypoxia+ultraviolet group showed the strongest inhibition of cell proliferation and induction of cell apoptosis, followed by the ultraviolet group and the hypoxia group. Compared with the control group, the other three groups had a gradual reduction in the mRNA expression of Bcl-2, and the hypoxia+ultraviolet group had a significantly greater reduction than the hypoxia and ultraviolet groups (P<0.01).

CONCLUSIONS

Both hypoxia and ultraviolet irradiation can inhibit the proliferation of HL-60 cells and induce cell apoptosis, and ultraviolet irradiation has a better effect on proliferation inhibition and cell apoptosis under hypoxic conditions than under normoxic conditions, possibly by downregulating the mRNA expression of Bcl-2.

[Effect of ultraviolet irradiation on the proliferation of acute promyelocytic leukemia cells under hypoxic conditions and related mechanisms]

OBJECTIVE

To study the effect of 280 nm-LED ultraviolet irradiation on the proliferation of acute promyelocytic leukemia (APL) HL-60 cells under hypoxic conditions and related mechanism.

METHODS

HL-60 cells in the logarithmic growth phase were selected and divided into control, hypoxia, ultraviolet and hypoxia+ultraviolet groups. The cells in the hypoxia group were treated with cobalt chloride (with a final concentration of 150 μmol/L), those in the ultraviolet group were irradiated by 280 nm-LED ultraviolet with an energy intensity of 30 J/m², and those in the hypoxia+ultraviolet group were treated with cobalt chloride and then irradiated by 280 nm-LED ultraviolet. After 48 hours of treatment, the cells were placed under an invert microscope to observe cell morphology. CCK-8 assay was used to measure the inhibition rate of cell proliferation. Annexin V-FITC/PI double staining flow cytometry was used to evaluate cell apoptosis. Quantitative real-time PCR was used to measure the mRNA expression of Bcl-2. Each experiment above was repeated three times independently.

RESULTS

Compared with the control group, the experimental groups showed shrinkage, decreased brightness, and disordered arrangement of cells, and the number of cells decreased over the time of culture. There were significant differences in the inhibition rate of cell proliferation and cell apoptosis rate among the groups (P<0.01), and the hypoxia+ultraviolet group showed the strongest inhibition of cell proliferation and induction of cell apoptosis, followed by the ultraviolet group and the hypoxia group. Compared with the control group, the other three groups had a gradual reduction in the mRNA expression of Bcl-2, and the hypoxia+ultraviolet group had a significantly greater reduction than the hypoxia and ultraviolet groups (P<0.01).

CONCLUSIONS

Both hypoxia and ultraviolet irradiation can inhibit the proliferation of HL-60 cells and induce cell apoptosis, and ultraviolet irradiation has a better effect on proliferation inhibition and cell apoptosis under hypoxic conditions than under normoxic conditions, possibly by downregulating the mRNA expression of Bcl-2.

[Effect of glutamine-supplemented enteral nutrition on the apoptosis of colonic mucosal cells in young rats with inflammatory bowl disease]

OBJECTIVE

To study the effect of glutamine-supplemented enteral nutrition in regulating the apoptosis of intestinal mucosal cells and promoting mucosal healing in young rats with inflammatory bowl disease (IBD).

METHODS

A total of 80 male Sprague-Dawley rats aged 4-5 weeks were randomly divided into 4 groups: blank control, IBD model, short peptide, and short peptide+glutamine (n=20 each). The IBD model was prepared by a single colon perfusion of 3-nitrobenzene sulfonic acid. At 3 days after modeling, the rats in the short peptide group were fed with short peptide formula (100 mL/kg), and those in the short peptide+glutamine group were fed with short peptide formula (100 mL/kg) and glutamine (0.5 g/kg). The course of intervention was 1 week. General conditions were observed after the experiment and their intestinal mucosal tissue was obtained. Hematoxylin-eosin staining was used to observe the pathological change of the intestinal mucosa. RT-PCR was used to measure the expression of apoptosis-regulating genes (bax and bc1-2) and apoptotic signal transduction factors (Caspase-3 and Caspase-9) in the intestinal mucosa. Western blot was used to measure the expression of insulin-like growth factor-1 (IGF-1) in the colonic mucosa.

RESULTS

The IBD model group had poorer general conditions than the other three groups (blank control, short peptide and short peptide+glutamine), and the short peptide+glutamine group had better general conditions than the IBD model and short peptide groups. The IBD model group had significantly higher mRNA expression of bax than the other three groups (P<0.05). There was no significant difference in the mRNA expression of bcl-2, Caspase-3 and Caspase-9 among the 4 groups (P>0.05). The short peptide group had a significantly higher level of IGF-1 than the short peptide+glutamine, blank control and IBD model groups (P<0.05).

CONCLUSIONS

Glutamine-supplemented enteral nutrition can effectively improve the general nutritional status of young rats with IBD, but it is not better than exclusive enteral nutrition in inhibiting the apoptosis of colonic mucosal cells and stimulating the synthesis of IGF-1 in the intestinal mucosa.

[Effect of propofol and operative trauma on neurodevelopment and cognitive function of developing brain in rats]

OBJECTIVE

To investigate the effect of propofol and operative trauma on the neurodevelopment and cognitive function of the developing brain and its mechanism.

METHODS

A total of 104 postnatal day 13 Sprague-Dawley rats were randomly divided into 4 groups: control group (treated by 7.5 mL/kg saline and sham surgery), propofol group (treated by 75 mg/kg propofol), surgery group (with abdominal surgery under local anesthesia) and propofol+surgery group (with abdominal surgery under local anesthesia plus 75 mg/kg propofol anesthesia). Thirteen rats from each group were randomly selected for detecting the content of TNF-α in the hippocampus and the expression levels of caspase-3 and c-fos in the brain. Morris Water Maze test was used to detect the cognitive ability of the other rats at 60 days old, after which TNF-α content in the hippocampus and caspase-3 and c-fos expressions in the brain were detected.

RESULTS

In 13 day-old rats, TNF-α level and caspase-3 and c-fos expressions differed significantly between the surgery group and the other 3 groups (P<0.05) and were similar among the control group, propofol group and propofol+surgery group (P>0.05). In 60-day-old rats, Morris water maze test results, TNF-α level or expressions of caspase-3 and c-fos showed no significant differences among the 4 groups.

CONCLUSION

Abdominal surgery can induce inflammation in the hippocampus and neuroapoptosis in neonatal rats rather than adult rats. Single-dose propofol anesthesia does not significantly affect neurodevelopment of young rats, and can relieve central inflammatory reaction induced by surgical trauma.

[Effects of simvastatin on aortic vascular endothelial cell apoptosis and Bcl-2 protein expression in a rat model of atherosclerosis]

OBJECTIVE

To explore the effects of simvastatin on vascular endothelial cell apoptosis and Bcl-2 protein expression in the aorta in a rat model of atherosclerosis.

METHODS

Thirty-six rats were randomized into control group (n=10), atherosclerosis model group (n=13) and simvastatin intervention group (n=13). In the latter two groups, rat models of atherosclerosis were established by intraperitoneal injection of vitamin D3 combined with high-fat feeding for 6 weeks, and the control rats were fed with regular diet. In the intervention group, the rats were further fed with high-fat diet with daily simvastatin treatment for 4 weeks. After the treatments, the pathological changes and plaque in the thoracic aorta were observed, and the expression of Bcl-2 protein was detected with immunohistochemistry. TUNEL assay was used to determine the apoptosis index (AI) of the vascular endothelial cells.

RESULTS

Compared with that in the control group, Bcl-2 protein expression in the aorta of atherosclerotic rats was significantly decreased (P<0.05); simvastatin treatment obviously increased the expression of Bcl-2 protein in atherosclerotic rats (P<0.05) to a level similar to that in the control group. The AI was the highest in the model group (P<0.05) and comparable between the control and simvastatin treatment group.

CONCLUSION

The therapeutic effect of simvastatin against atherosclerosis is probably mediated by up-regulation of Bcl-2 protein, which inhibits vascular endothelial cell apoptosis in rats with aortic atherosclerosis.

[Role of aquaporin-5 in regulating colorectal cancer cell growth in vitro]

OBJECTIVE

To study the role of aquaporin 5(AQP5) in regulating the cell proliferation and apoptosis of human colorectal cancer cells and explore the possible mechanism.

METHODS

A small interfering RNA (siRNA) targeting AQP5 was used to suppress endogenous AQP5 expression in the human colorectal cancer cell lines COLO 205 and SW480, and the transfection efficiency of AQP5 siRNA was determined using immunofluorescence assay and PCR. The changes in the proliferation of the transfected cells was evaluated with MTT assay, and the cell apoptosis was analyzed using Annexin V-FITC/PI and TUNEL assays; the changes of Bax and Bcl2 expressions in the cells were determined using RTPCR and Western blotting.

RESULTS

Transfection with AQP-5-siRNA resulted in a significant reduction (up to 90%) of AQP-5 expression in COLO 205 and SW480 cells. MTT assay showed that AQP-5-siRNA transfection significantly inhibited the cell proliferation compared NS siRNA transfection (P<0.05). Flow cytometric analysis revealed significantly increased apoptotic rate of cells following AQP-5-siRNA transfection compared with NS?siRNA transfection(P<0.05). Real-time quantitative RT-PCR and Western blotting demonstrated that AQP-5-siRNA transfection significantly increased Bax and Bcl-2 expressions at both mRNA and protein levels in the cells.

CONCLUSION

AQP5-siRNA can promote apoptosis of colorectal cancer cells in vitro possibly in relation to its effects on Bax and Bcl expressions.

[Inhibitory effect of giganteaside D on hepatocellular carcinoma Hep 3b cells and the underlying mechanisms]

OBJECTIVE

To investigate the inhibitory effect of giganteaside D (GD) on hepatocellular carcinoma and its molecular mechanisms.

METHODS

The inhibitory effects of GD on Hep 3b cells were determined using MTT assay and colony formation assay. The morphological changes of Hep 3b cells after GD treatment were observed by electron microscopy, and the cell cycle changes was analyzed using flow cytometry. The cell apoptosis and mitochondrial potential collapse in the treated cells were tested with Hoechst staining assay and flow cytometry. The expression levels of Bcl-2, PARP and key proteins in MAPK pathway were detected using Western blotting.

RESULTS

GD showed a significant inhibitory effect on Hep 3b cells with an IC₅₀ value of 16.08 µmol/L at 72 h. Flow cytometric analysis demonstrated that the phases of cell cycle remained unchanged and a sub-G1 peak (from 3.3% to 33.6%) appeared as GD concentration increased. GD-induced apoptosis was further conformed by Hoechst staining assay, and flow cytometry showed increased mitochondrial potential collapse in the cells. Western blotting demonstrated the cleavage of PARP, decrease of Bcl-2 and p-Erk1/2 (Thr202/Tyr204), and activation of p-p38 (Thr180/Tyr182) and p-JNK (Thr183/Tyr185) in GD-treated cells.

CONCLUSIONS

GD has significant inhibitory effect against hepatocellular carcinoma cells in vitro by inducing apoptosis possibly in association with the MAPK signaling pathway.

[Quinalizarin induces apoptosis in gastric cancer AGS cells via MAPK and Akt signaling pathway]

OBJECTIVE

To investigate quinalizarin-induced apoptosis in gastric cancer cells in vitro and explore the molecular mechanisms.

METHODS

MTT assay was used to determine the cytotoxic effects of quinalizarin on human gastric cancer AGS, MKN-28 and MKN-45 cells. Annexin V-FITC/PI staining and flow cytometry were used to assess quinalizarin-induced apoptosis in AGS cells and its effect on intracellular ROS levels; the expression levels of apoptotic proteins in the cells were determined with Western blotting.

RESULTS

Quinalizarin dose-dependently reduced the cell viabilities of the 3 gastric cancer cells (P<0.05). The IC₅₀ values of quinalizarin in AGS, MKN-28 and MKN-45 cells were 7.07 µmol/L, 22.55 µmol/L and 14.18 µmol/L, respectively. Quinalizarin time-dependently induced apoptosis of AGS cells and potentiated the generation of intracellular reactive oxygen species (ROS) levels. Pretreatment with NAC, a scavenger of ROS, inhibited quinalizarin-induced apoptosis (P<0.001). Western blotting results showed that quinalizarin also up-regulated the expression levels of the apoptotic proteins including p-p38, p-JNK, Bad, cleaved caspase-3, and cleaved PARP-1 (P<0.05), and down-regulated the expression of the anti-apoptotic proteins p-Akt, p-ERK, and Bcl-2 (P<0.05).

CONCLUSION

Quinalizarin inhibits the proliferation and induces apoptosis in gastric cancer cells in vitro through regulating intracellular ROS levels via the MAPK and Akt signaling pathways.

肝星状细胞衰老与增殖、凋亡的关系

肝星状细胞(hepatic stellate cells, HSCs)活化、细胞外基质大量形成是肝纤维化发生发展的关键环节. 许多研究发现, 抑制HSCs增殖、促进HSCs凋亡可阻断肝纤维化进程; 同时研究发现, 促进活化HSCs衰老也可为肝纤维化的防治提供新的策略. 本文就HSCs衰老与增殖、凋亡的关系以及在肝纤维化中的作用相关研究进展予以综述.

[Effect of telomerase activation on biological behaviors of neural stem cells in rats with hypoxic-ischemic insults]

OBJECTIVE

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

METHODS

The 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.

RESULTS

After 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.

CONCLUSIONS

Telomerase 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.

[Effect of telomerase activation on biological behaviors of neural stem cells in rats with hypoxic-ischemic insults]

OBJECTIVE

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

METHODS

The 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.

RESULTS

After 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.

CONCLUSIONS

Telomerase 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.

[The neuroprotective role of exogenous TERT gene in neonatal rats with hypoxic-ischemic brain damage]

OBJECTIVE

To study the effect of telomerase reverse transcriptase (TERT) on cell apoptosis in neonatal rat brains after hypoxic-ischemic brain injury (HIBD).

METHODS

A total of 72 neonatal rats were divided into sham, vehicle, HIBD and TERT groups. HIBD was induced by Rice method in the later three groups. The neonatal rats in the vehicle and TERT groups were injected with plasmids containing mock or full length TERT by an intracerebroventricular injection 30 minutes after hypoxic-ischemic (HI) injury. Pathological changes of brain tissue were observed by hematoxylin and eosin (HE) staining. Western blot was used to detect the protein expression of TERT, apoptosis-inducing factor (AIF) and cleaved caspase 3 (CC3). Apoptotic cells were detected by TUNEL staining.

RESULTS

Western blot showed that TERT protein was dramatically increased in the vehicle, HIBD and TERT groups compared with the sham group. Compared with the vehicle and HIBD groups, TERT protein in the TERT group was significantly upregulated. Compared with the sham group, there was a significant increase in apoptotic index and expression of AIF and CC3 proteins in the vehicle and HIBD groups (p<0.01). The TERT group showed decreased expression of AIF and CC3 proteins and apoptotic index compared with the vehicle and HIBD groups (p<0.01).

CONCLUSIONS

TERT can inhibit cell apoptosis induced by HI and might have a neuroprotective role in developing brain with HIBD.

[The neuroprotective role of exogenous TERT gene in neonatal rats with hypoxic-ischemic brain damage]

OBJECTIVE

To study the effect of telomerase reverse transcriptase (TERT) on cell apoptosis in neonatal rat brains after hypoxic-ischemic brain injury (HIBD).

METHODS

A total of 72 neonatal rats were divided into sham, vehicle, HIBD and TERT groups. HIBD was induced by Rice method in the later three groups. The neonatal rats in the vehicle and TERT groups were injected with plasmids containing mock or full length TERT by an intracerebroventricular injection 30 minutes after hypoxic-ischemic (HI) injury. Pathological changes of brain tissue were observed by hematoxylin and eosin (HE) staining. Western blot was used to detect the protein expression of TERT, apoptosis-inducing factor (AIF) and cleaved caspase 3 (CC3). Apoptotic cells were detected by TUNEL staining.

RESULTS

Western blot showed that TERT protein was dramatically increased in the vehicle, HIBD and TERT groups compared with the sham group. Compared with the vehicle and HIBD groups, TERT protein in the TERT group was significantly upregulated. Compared with the sham group, there was a significant increase in apoptotic index and expression of AIF and CC3 proteins in the vehicle and HIBD groups (p<0.01). The TERT group showed decreased expression of AIF and CC3 proteins and apoptotic index compared with the vehicle and HIBD groups (p<0.01).

CONCLUSIONS

TERT can inhibit cell apoptosis induced by HI and might have a neuroprotective role in developing brain with HIBD.

[Effects of PINK1 gene on cell apoptosis and cell autophagy in neonatal mice with hypoxic-ischemic brain damage]

OBJECTIVE

To study the effect of PINK1 (phosphatase and tensin homolog deleted on chromosome ten induced putative kinase 1) gene on cell apoptosis and cell autophagy in neonatal mice with hypoxic-ischemic brain damage (HIBD).

METHODS

Seventy-two wild-type C57BL/6 mice and 72 PINK1 gene knockout neonatal C57BL/6 mice were randomly divided into four groups: sham-operated wild-type (SWT), HIBD model wild-type (MWT), sham-operated knockout (SKO) and HIBD model knockout (MKO). HIBD model was prepared by low oxygen exposure for 2.5 hours after right carotid artery ligation. After 24 hours of hypoxia-ischemia treatment, TTC (2,3,5-triphenyl four azole nitrogen chloride) staining was used to measure brain infarct volume. The immunohistochemical staining was used to measure the expression of cell apoptosis protein cleaved-caspase-3 (CC3) in brain tissues. The TUNEL method was used to measure cell apoptosis. The immunofluorescence staining and Western blot were used to measure the expression of cell autophagy protein LC3.

RESULTS

Compared with the MWT group, the infarct volume of brain tissues was markedly reduced in the MKO group (P<0.05), the number of apoptotic cells and the cell apoptosis index were markedly decreased in the MKO group (P<0.05), the expression of apoptosis protein CC3 was significantly reduced in the MKO group (P<0.05), the expression of cell autophagy protein LC3 was significantly decreased in the MKO group, and the autophagy indicator LC3II/LC3I was also markedly reduced in the MKO group (P<0.05).

CONCLUSIONS

PINK1 gene knockout can protect neonatal mice from HIBD.

[RNA interference of HERC4 inhibits proliferation, apoptosis and migration of cervical cancer Hela cells]

OBJECTIVE

To explore the effects of silencing HERC4 on the proliferation, apoptosis, and migration of cervical cancer cell line Hela and the possible molecular mechanisms.

METHODS

Three HERC4-specific small interfering RNAs (siRNAs) were transfected into Hela cells, and HERC4 expression in the cells was examined with Western blotting. CCK-8 assay, annexin V-FITC/PI assay, and wound healing assay were used to assess the effect of HERC4 silencing on the proliferation, apoptosis and migration ability of Hela cells. The expression levels of cyclin D1 and Bcl-2 in the cells were detected using Western blotting.

RESULTS

Transfection of siRNA-3 resulted in significantly decreased HERC4 protein expression (P<0.01). HERC4 silencing by siRNA-3 markedly suppressed the proliferation and migration of Hela cells, increased the apoptosis rate (P<0.01) and reduced the expression levels of cyclin D1 and Bcl-2 (P<0.01).

CONCLUSION

Silencing of HERC4 efficiently inhibits the proliferation, migration, and invasion of Hela cells in vitro, and the underlying mechanisms may involve the down-regulation of cyclin D1 and Bcl-2.

[Role of calcineurin-nuclear factor of activated T cells signaling pathway in myoblast apoptosis induced by cyclic tensile strain]

OBJECTIVE

This study investigated the role and mechanism of calcineurin (CaN)-nuclear factor of activated T cells (NFAT) pathway in the myoblast apoptosis induced by cyclic tensile strain.

METHODS

Myoblasts were cultured using an in vitro-mechanical stimulation model and imposed with tension for different hours with a multi-channel cell stress loading system. Cyclosporine (CsA) was used as CaN inhibitor to clarify the role of CaN in the apoptosis induced by cyclic stress. Hochest 33258 staining and flow cytometry detection were performed to detect the apoptotic cells. Real-time polymerase chain reaction was conducted to detect the mRNA expression of CaN and NFAT. Protein levels of NFAT3 were evaluated by Western blot.

RESULTS

The apoptosis rate increased with the extension of loading time. The mRNA expression of the CaN subunits, CnA and CnB, and the protein levels of NFAT3 also increased. When the myoblasts were incubated with CsA, the apoptosis rate decreased, the mRNA expression of CnA and NFAT3 significantly decreased, and the NFAT3 protein expression levels became significantly lower than those of the groups without CsA.

CONCLUSION

Continuous cyclic tensile stress can induce myoblast apoptosis. The CaN-NFAT signaling pathway may be involved in the cyclic stretch-induced apoptosis of myoblasts.

[In vitro study of BRD4 inhibitor GSK525762A against primary adult common B-cell acute lymphoblastic leukemia cells in vitro]

OBJECTIVE

To investigate the effects of bromodomain-containing protein 4 (BRD4) inhibitor GSK525762A on the proliferation and apoptosis of primary common B-cell acute lymphoblastic leukemia (common B-ALL) cells from adult patients, then to further explore the possible mechanisms.

METHODS

Purified leukemia cells from 14 common B-ALL adult patients (4 Ph⁺ and 10 Ph⁻ cases) were obtained by flow cytometry sorting, and maintained in a mimic bone marrow microenvironment culture system for short-term culture. Leukemia cells were treated with various concentrations of GSK525762A. The inhibitory effects of BRD4 inhibitor on common B-ALL leukemia cells were measured by CCK-8 assay and the apoptosis of those cells was determined by AnnexinⅤ/7-AAD staining using flow cytometry. The transcripts of c-MYC, CDK6 and Bcl-2 were detected by quantitative RT-PCR, and the expression of c-MYC, CDK6 and Bcl-2 proteins were detected via Western blot.

RESULTS

GSK525762A could inhibit the proliferation of leukemia cells from all 14 common B-ALL patients in a dose-dependent manner, the median value of IC50 was 256.25 (90.64-1 378.39)nmol/L. GSK525762A could promote cells apoptosis of B-ALL leukemia cells in a dose-dependent manner, the median apoptosis rates respectively were 45.17%(9.38%-70.91%), 66.02% (24.36%-96.34%) and 89.29% (39.29%-99.37%) after treated by 500, 1 000 and 2 500 nmol/L GSK525762A. GSK525762A has a similar effect on Ph⁺ ALL and Ph⁻ B-ALL, but the effect of proliferation inhibition and apoptosis enhancement on Ph+ B-ALL is weaker than that on Ph⁻ B-ALL. Compared with vehicle control group, the levels of c-MYC, Bcl-2 and CDK6 transcripts in leukemic cells were reduced after treatment for 24 h and 48 h by 1 000 nmol/L GSK525762A, and there are no significant differences in the downregulation of c-MYC and CDK6 mRNA between Ph⁺ and Ph⁻ B-ALL; however, the inhibitory effect on Bcl-2 transcription was weaker in Ph⁺ B-ALL cells than that in Ph⁻ B-ALL cells. Moreover, c-MYC, Bcl-2 and CDK6 protein levels decreased in GSK525762A treated group.

CONCLUSION

GSK525762A could strongly inhibit the proliferation of common B-ALL and trigger apoptosis; meanwhile it has certain effects against Ph⁺ ALL in vitro. The effect may be achieved by down-regulation of c-MYC, CDK6 and Bcl-2 expression.

[Excessive fluoride inducing calcium overload and apoptosis of ameloblasts]

OBJECTIVE

To study the effect of excessive fluoride on calcium overload and apoptosis in cultured rat ameloblasts in vitro.

METHODS

Logarithmic-phase ameloblasts (HAT-7) were treated with 0, 0.4, 0.8, 1.6, 3.2, and 6.4 mmol · L(-1) sodium fluoride (NaF) solution. Cell activities were detected by using a Cell Counting Kit 8 (CCK-8) assay after 48 h of treatment. The effect of fluoride on cell apoptosis was analyzed by using flow cytometry. Excessive fluoride-induced calcium concentration and calreticulin expression changes in ameloblasts were detected by using laser scanning confocal microscopy, Western blot analysis, and real-time quantitative polymerase chain reaction.

RESULTS

NaF inhibited ameloblast activity at 1.6, 3.2, and 6.4 mmol · L(-1) (dose-dependent) after 48 h of induction. The Ca2+ fluorescence intensity of HAT-7 cells incubated with 1.6 and 3.2 mmol · L(-1) NaF was higher than that in the control group. The fluoride-induced early-stage apoptosis of ameloblasts after 48 h of induction and the early-stage apoptosis rate was positively correlated with fluoride concentration. Calreticulin mRNA expression in HAT-7 cells was higher than that in the control group after 48 h of incubation with 0.8, 1.2, and 1.6 mmol · L(-1) NaF.

CONCLUSION

Excessive fluoride-induced calcium overload in ameloblasts and further caused endoplasmic reticulum stress-mediated apoptosis.