A novel PI3K inhibitor XH30 suppresses orthotopic glioblastoma and brain metastasis in mice models

Glioblastoma is carcinogenesis of glial cells in central nervous system and has the highest incidence among primary brain tumors. Brain metastasis, such as breast cancer and lung cancer, also leads to high mortality. The available medicines are limited due to blood-brain barrier. Abnormal activation of phosphatidylinositol 3-kinases (PI3K) signaling pathway is prevalent in glioblastoma and metastatic tumors. Here, we characterized a 2-amino-4-methylquinazoline derivative XH30 as a potent PI3K inhibitor with excellent anti-tumor activity against human glioblastoma. XH30 significantly repressed the proliferation of various brain cancer cells and decreased the phosphorylation of key proteins of PI3K signaling pathway, induced cell cycle arrest in G1 phase as well. Additionally, XH30 inhibited the migration of glioma cells and blocked the activation of PI3K pathway by interleukin-17A (IL-17A), which increased the migration of U87MG. Oral administration of XH30 significantly suppressed the tumor growth in both subcutaneous and orthotopic tumor models. XH30 also repressed tumor growth in brain metastasis models of lung cancers. Moreover, XH30 reduced IL-17A and its receptor IL-17RA in vivo. These results indicate that XH30 might be a potential therapeutic drug candidate for glioblastoma migration and brain metastasis.

Oxygen impact on genome structure and chemistry / 药学学报

Oxygen is an essential element for life, which is mostly consumed at mitochondria for energy metabolism. For the genome inside nucleus, oxygen conducts structural regulations and chemical modifications through multiple pathways, where reactive oxygen species (ROS) serve as important messenger molecules. The highly activated ROS have the ability to produce different kinds of DNA lesions, while ferrous ions provide supports in many forms. Under the combinatorial action of oxygen and iron, almost all the genomic biochemical processes, such as replication, transcription and DNA damage repair are affected. Moreover, the variation of environmental oxygen concentration, particularly hypoxia that presents in many major diseases and critical physiological stages, provokes the responds at the genomic level. While the factors that lead to these genomic alterations are potential drug targets and deserve systematic investigations, herein, we collect the existing knowledge in the effects of ROS, ferrous ion and cell hypoxia on genome, along with brief discussions of the related drug molecules.

Inhibition of Sijunzi Decoction extract on human breast cancer cells MDA-MB-468 / 中草药

Objective: To investigate the effect of Sijunzi Decoction extract (SDE) on the growth of human triple negative breast cancer (TNBC) cell line MDA-MB-468. Methods: MDA-MB-468 cells were treated with different concentrations of SDE. The effect of SDE on the proliferation and migration of the cells were detected by CCK-8 assay and the cell wound healing assay. The colony formation assay was performed to analyze the effect on the ability of colony formation of the cells with SDE. Hoechst 33342 staining technique and flow cytometry (FCM) were used to detect apoptosis and cell cycle of the cells. Western blotting was used to detect the expression levels of STAT3, which was related with the proliferation and apoptosis of cells. Results: Compared with the control group, SDE had a certain inhibitory effect on MDA-MB-468 cells (P < 0.05), and it was dependent on the concentration and time. Cloning formation experiments showed that SDE inhibited the clonality of the cells. The cell migration experiment showed that the wound healing ability of the cells could be weakened by the extract with the medium and high dosage (P < 0.001). The results of FCM showed that the apoptosis rate of all SDE dosage increased gradually in a dose-dependent manner. And SDE with the medium and high dosage induced apoptosis of the cells significantly (P < 0.01 and 0.001). Cell cycle was affected by SDE with the obvious reduction of the cells in G2 phase (P < 0.01). The results of Western blotting showed that the expression level of STAT3 was decreased significantly. Conclusion: SDE inhibited the proliferation and clonal formation of MDA-MB-468 cells, inhibited migration, promoted apoptosis and decreased the cells of G2 phase. which may be related to the regulation of STAT3 pathway.

Effect of parallel double locking plate fixation on the indexes of trauma and bone metabolism in patients with distal humerus type C fracture / 国际外科学杂志

Objective:To investigate the effect of parallel double locking plate fixation on the postoperative trauma and bone metabolism in patients with distal humerus type C fracture.Methods:Retrospective analysis of clinical data of 75 patients with type C fracture of distal humerus admitted to the department of orthopedics, Baogang Hospital, Inner Mongolia from January 2017 to January 2019 was conducted. There were 46 males and 29 females, aged (45.14 ± 10.36) years and ranging from 22 to 69 years. According to the internal fixation method, they were divided into the control group ( n=36) and the observation group ( n=39). The control group was treated with Y-plate internal fixation, and the observation group was treated with parallel double locking plate fixation, which was compared with the operation time, intraoperative bleeding, fracture healing time and the excellent and good rate of elbow joint function of the two groups. The levels of LDH, ckeatine kinase, GPT, GOT, C3 and C4 were compared between the two groups. The bone metabolism indexes of the two groups were Osteocalcin, BALP, PINP, CTX and TRAP. The level of PYD and complications of the two groups were compared. The measurement data were expressed as mean±standard deviation ( Mean± SD), the t test was used for comparison between groups, and the count data were expressed as percentage (%), the chi-square test was used for comparison between groups. Results:There was no significant difference in operative time and intraoperative hemorrhage between the two groups ( P>0.05). The fracture healing time of the observation group was (10.22±2.16) weeks, shorter than that of the control group (13.63 ± 2.39) weeks, with a statistically significant difference ( P<0.05), the excellent and good rate of elbow joint function of the observation group was 82.05%(32/39), higher than that of the control group (61.11%, 22/36), with a statistically significant difference ( P<0.05). The levels of LDH, creatine kinase, GPT, GOT in the observation group were (205.36±20.51) U/L, (25.19±3.97) U/L, (11.37±2.04) U/L, (9.35±1.02) U/L, respectively, which were lower than those in the control group [(248.95±22.73) U/L, (41.85±4.64) U/L, (18.76±2.12) U/L, (16.68±1.34) U/L], complement C3 and C4 were (1.48 ± 0.16) g/L, (0.45 ± 0.07) g/L, which were higher than those of the control group [(1.15±0.14) g/L, (0.23±0.06) g/L], the difference was statistically significant ( P<0.05). Osteocalcin, BALP and PINP in the observation group were (6.27 ± 0.92) μg/L, (71.05 ± 7.46) IU/L, (92.39 ± 7.12) ng/mL, respectively, which were higher than those in the control group [(5.63 ± 0.76) μg/L, (64.82 ± 6.88) IU/L, (79.47 ± 8.64) ng/mL]. The levels of CTX, TRAP and PYD in the observation group were (5.52 ± 0.96) ng/mL, (3.47 ± 0.61) U/L, (25.07 ± 4.02) U/L, respectively, which were lower than those in the control group [(6.38 ± 0.99) ng/mL, (4.40 ± 0.73) U/L, (29.14 ± 3.85) U/L], with a statistically significant difference ( P<0.05), the incidence of postoperative complications in the observation group was 10.26% (4/39), lower than 30.56% (11/36) in the control group, with a statistically significant difference ( P<0.05). Conclusions:The treatment of C-type fracture of distal humerus with parallel double locking plate can improve the elbow joint function. The postoperative trauma is lighter, the bone metabolism is better, and it has more advantages than Y-type plate internal fixation, which is worth popularizing.

Mechanisms of doxorubicin resistance of breast cancer MCF-7 cells mediated by exosomes / 药学学报

This study aimed to explore the roles of exosomes in doxorubicin-resistance in breast cancer cells. Using breast cancer parental cell line (MCF-7), doxorubicin-resistant cell line (MCF-7/ADR) and sensitive cell line co-cultured with doxorubicin-resistant supernatant (MCF-7/EXO) as models, the effects of doxorubicin on proliferation or apoptosis of MCF-7, MCF-7/EXO and MCF-7/ADR cells were detected by CCK8, and light or fluorescent microscopy. Exosomes in the supernatants of cell culture were extracted by ultracentrifugation, and the quantity of exosomes was determined by transmission electron microscopy, BCA and DiI labeling assay. Expression levels of exosome-specific biomarkers CD63 and Flotillin-1 were detected by Western blot. The uptake of MCF-7/ADR cell-derived exosomes by MCF-7 cells was observed by laser confocal microscopy. Western blot was used to detect the expression levels of multidrug resistance protein ATP-binding cassette subfamily B member 1 (ABCB1) in all three cell strains. Cell proliferation assays showed that IC50 of MCF-7/EXO cells to doxorubicin was 0.83 ± 0.09 μmol·L-1, which was significantly higher than 0.15 ± 0.05 μmol·L-1 (P<0.01) of MCF-7 cells, suggesting 5.5 times of increase in drug resistance. Apoptosis of MCF-7 cells was induced after doxorubicin treatment (P<0.001), but MCF-7/EXO cells were not significantly different (P>0.05). Exosome quantification and specific marker detection showed that MCF-7/EXO cells had significantly more exosomes than MCF-7 cells (P<0.05). PKH67 tracer markers indicated that MCF-7/ADR-derived exosomes could be taken up by MCF-7 cells. Western blot showed that the expression level of ABCB1 protein in MCF-7/EXO cells was significantly higher than that in MCF-7 cells. Taken together, these results indicate that exosomes of doxorubicin-resistant breast cancer cells can transmit drug resistance to sensitive cells, and the underlying mechanism may involve ABCB1 protein transport mediated by exosomes.

Advances in understanding exosomes-mediated tumor chemoresistance / 药学学报

Chemotherapy plays an essential role in controlling tumor growth and progression. However, long-term use of chemotherapeutic drugs usually results in drug resistance in tumor cells, leading to treatment failure and disease progression. The mechanism of tumor resistance to chemotherapy and the strategy of prevention or reversal of such resistance have always been hot issues in cancer therapy research. Exosomes are small spherical vesicles secreted by cells with a diameter of 40-100 nm. They carry a variety of bioactive small molecules (including DNA, ncRNA, RNA, and proteins) and participate in regulation of cell microenvironment, thereby affecting a variety of physiological and pathological activities in the body. In recent years, studies have shown that exosomes play an important role in cancer cell resistance to chemotherapy, metastasis, and immune escape. This article reviews the role and mechanism of exosomes in the development of drug resistance in tumors, and aims to provide new ideas for the prevention or treatment of tumor resistance.

DNA recognition patterns of the multi-zinc-finger protein CTCF: a mutagenesis study

CCCTC-binding factor (CTCF) is a zinc-finger protein, serving an important part in the genome architecture as well as some biochemical processes. Over 70,000 CTCF binding DNA sites have been detected genome-wide, and most anchors of chromatin loops are demarcated with the CTCF binding. Various protein or RNA molecules interact with DNA-bound CTCF to conduct different biological functions, and potentially the interfaces between CTCF and its cofactors can be targets for drug development. Here we identify the effective region of CTCF in DNA recognition, which defines the exposed CTCF surface feature for the interaction of cofactors. While the zinc-finger region contributes the most in DNA association, its binding affinity varies based on different DNA sequences. To investigate the effectiveness of individual zinc-fingers, the key residues are mutated to inactivate the DNA binding ability, while the finger configuration and the spacing between fingers are preserved. The strategy is proved to be successful, while clear differences are observed in the DNA binding affinities among the 11 finger mutants and the result is consistent to previous studies in general. With the help of inactivated finger mutants, we identify the ineffective fingers and the dominant effective fingers, which form distinctive patterns on different DNA targets.

E17110 promotes reverse cholesterol transport with liver X receptor β agonist activity in vitro

Liver X receptor (LXR) plays an important role in reverse cholesterol transport (RCT), and activation of LXR could reduce atherosclerosis. In the present study we used a cell-based screening method to identify new potential LXRβ agonists. A novel benzofuran-2-carboxylate derivative was identified with LXRβ agonist activity: E17110 showed a significant activation effect on LXRβ with an EC50 value of 0.72 μmol/L. E17110 also increased the expression of ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1) in RAW264.7 macrophages. Moreover, E17110 significantly reduced cellular lipid accumulation and promoted cholesterol efflux in RAW264.7 macrophages. Interestingly, we found that the key amino acids in the LXRβ ligand-binding domain had distinct interactions with E17110 as compared to TO901317. These results suggest that E17110 was identified as a novel compound with LXRβ agonist activity in vitro via screening, and could be developed as a potential anti-atherosclerotic lead compound.

The Ikaros family of zinc-finger proteins

Ikaros represents a zinc-finger protein family important for lymphocyte development and certain other physiological processes. The number of family members is large, with alternative splicing producing various additional isoforms from each of the five homologous genes in the family. The functional forms of Ikaros proteins could be even more diverse due to protein-protein interactions readily established between family members. Emerging evidence suggests that targeting Ikaros proteins is feasible and effective in therapeutic applications, although the exact roles of Ikaros proteins remain elusive within the intricate regulatory networks in which they are involved. In this review we collect existing knowledge as to the functions, regulatory pathways, and molecular mechanisms of this family of proteins in an attempt to gain a better understanding through the comparison of activities and interactions among family members.

Small interfering RNA targeting STAT3 enhances the drug susceptibility of adriamycin in breast cancer cells / 中国药学杂志

OBJECTIVE: To further define the modulation effect of signal transducers and activators of transcription 3 (STAT3) in adriamycin-resistant breast cancer and to promote the clinical application of the inhibitors of STAT3 in reversing multidrug resistance in cancer. METHODS: Firstly, the levels of STAT3 and phosphorylated STAT3 (pSTAT3) expression in clinical breast cancer tissue samples were determined by Western blotting. The expression of STAT3 and pSTAT3 in adriamycin-sensitive and adriamycin-resistant breast cancer cell lines was evaluated by RT-PCR and Western blotting. Secondly, the expression of STAT3 was detected by Western blotting after blocking the STAT3 signal pathway with small interfering RNA targeting STAT3 (STAT3-siRNA). Finally, after the expression of STAT3 was blocked by STAT3-siRNA, immunofluorescence was performed to study the proliferation activity of breast cancer cells and MTT was used to determine the IC50 of the cells in order to observe whether STAT3-siRNA had any inhibitory effects on the growth of breast cancer cells and whether it could promote the efficacy of adriamycin in breast cancer cells. RESULTS: STAT3 and pSTAT3 were highly expressed both in clinical breast cancer tissue samples and in adriamycin-sensitive-and-resistant breast cancer cells. The expression of pSTAT3 in adriamycin-resistant breast cancer cells was significantly higher than in adriamycin-sensitive breast cancer cells. STAT3-siRNA conspicuously decreased the expression of STAT3 protein and inhibited the growth of adriamycin-sensitive breast cancer cells. Compared with the single application of adriamycin, IC50 of adriamycin-resistant breast cancer cells decreased by 4 fold when adriamycin was used in combinaiton with STAT3-siRNA. Meanwhile, an inhibition of the expression of the anti-apoptotic protein mediated by STAT3 was observed in adriamycin-resistant breast cancer cells. CONCLUSION: This study reveals that the development of breast cancer is related to the activation of STAT3. The activation of STAT3 in adriamycin-resistant breast cancer cells was more notable than in adriamycin-sensitive cells. The inhibition of the STAT3 pathway could improve the adriamycin sensitivity of adriamycin-resistant breast cancer cells and lead to their apoptosis. The RESULTS of this study explores the feasibility of the reversal of drug resistance in cancer by blocking STAT3 pathway and establishes the experimental basis for promoting the clinical use of the inhibitors of STAT3 pathway and the chemotherapeutics to overcome the multidrug resistance in cancer.

Diagnostic performance of macular ganglion cell - inner plexiform layer thickness measured by Cirrus HD-OCT in POAG patients / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the diagnostic accuracy of macular ganglion cell - inner plexiform layer ( GCIPL ) measurements using high- definition optical coherence tomography ( Cirrus HD - OCT ) ganglion cell analysis algorithm for detecting early and moderate to severe glaucoma. METHODS:Twenty normal control persons, 26 patients with early glaucoma and 29 patients with moderate to severe glaucoma were enrolled in this study. Macular GCIPL, optic nerve head ( ONH ) parameters and peripapillary retinal nerve fiber layer ( RNFL ) thickness were measured in each subject. Then all measured results of each parameter were calculated using SPSS17. 0. Areas under the receiver operating characteristic curves ( AUC) of each parameter were calculated to compare the diagnostic accuracy for detecting early and moderate to severe glaucoma. RESULTS: For detecting early glaucoma, AUC of average RNFL and seven clock value of RNFL were the biggest ( 0. 871 and 0. 896 respectively ), the AUC of parameters in GCIPL were also significant, among them, the average GCIPL showed bigger AUC(0. 847) than the minimum GCIPL (0. 812). For diagnosing moderate to severe glaucoma, the AUC of rim area was 0. 992, which was bigger than that of average RNFL ( 0. 991 ). The minimum GCIPL showed bigger AUC ( 0. 983 ) than the average GCIPL (0. 967). For early glaucoma diagnosis, the sensitivity of average RNFL was the highest (76. 9%), while the average GCIPL has the highest specificity (93. 5%). CONCLUSION: AS a new diagnostic parameter for detecting glaucoma, GCIPL shows similar diagnostic potential compared with RNFL. For early glaucoma diagnosis, average RNFL is the most important parameter, while screening early glaucoma, average GCIPL should be paid more attention.

Research on Turmeric Fine Pulverizing Process and Its Powder Properties / 世界科学技术-中医药现代化

This paper was aimed to analyze and study the process of Turmeric fine pulverizing; and the powder properties of Turmeric ultra-micro powder after the process. Based on d50, the powder properties of Turmeric ultra-micro powder were summarized by using orthogonal design to select the optimal Turmeric fine pulverizing. Compari-sons were made on powder properties, such as exterior characters, IR spectra, fluidity and hygroscopicity before and after fine pulverizing. The results showed that optimal fine pulverizing process was determined based on orthogonal design. The conditions were that the material was 1 200 g, with water of 5.5% and crushing for 40 min. Compari-son of powder properties of Turmeric powders before and after fine pulverizing showed that as the diameter of the particle decreased. Turmeric particle gradually showed signs of aggregation. At the same time, granular sensation disappeared;the color turned lighter;powder became finer;fluidity was reduced;balanced hygroscopic capacity el-evated. Although the chemical composition and molecular structure had not changed;initial velocity and capacity of hygroscopicity increased, acceleration declined. It was concluded that Turmeric fine pulverizing was a convenient, reliable and practical process, with small size of particle. It can be used for Turmeric fine pulverizing. The compre-hensive evaluation showed that ultrafine powder four as the optimum powder.

C2H2 zinc-finger recognition of biomolecules / 药学学报

C2H2 zinc-finger motif presents in 3% of proteins that are encoded in the human genome, and has the abilities to recognize DNA, RNA and protein. With nearly 3 decades of efforts, the mechanisms of zinc-finger mediated biomolecule recognitions have been studied to various extents. Zinc-finger binds into the major groove of DNA double helix, establishes an one-to-one recognition format between DNA bases and certain amino acids in a zinc-finger, and achieves specificity based on DNA sequences. While RNA molecules show a large variety in their structures, zinc-finger recognizes RNA through the collected information of specially displayed bases and special backbone folding. Initial studies have been performed on zinc-finger mediated protein-protein interactions. Existing data indicate multiple recognition modes. The studies on molecular mechanism have supported the development of engineered zinc-fingers, which have been introduced into applications. For its wide existence, large functional diversity and potential in translational applications, zinc-finger deserves a systematic study in every aspect.

C2H2 zinc-finger recognition of biomolecules / 药学学报

C2H2 zinc-finger motif presents in 3% of proteins that are encoded in the human genome, and has the abilities to recognize DNA, RNA and protein. With nearly 3 decades of efforts, the mechanisms of zinc-finger mediated biomolecule recognitions have been studied to various extents. Zinc-finger binds into the major groove of DNA double helix, establishes an one-to-one recognition format between DNA bases and certain amino acids in a zinc-finger, and achieves specificity based on DNA sequences. While RNA molecules show a large variety in their structures, zinc-finger recognizes RNA through the collected information of specially displayed bases and special backbone folding. Initial studies have been performed on zinc-finger mediated protein-protein interactions. Existing data indicate multiple recognition modes. The studies on molecular mechanism have supported the development of engineered zinc-fingers, which have been introduced into applications. For its wide existence, large functional diversity and potential in translational applications, zinc-finger deserves a systematic study in every aspect.

Predictive value of (99)Tc(m)-MIBI scintimammography in evaluation of the efficacy of neoadjuvant chemotherapy in patients with operable breast cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the value of technetium-99m methoxyisobutylisonitrile ((99)Tc(m)-MIBI) imaging in predicting the efficacy of neoadjuvant chemotherapy (NCT) and prognosis in patients with operable breast cancer.</p><p><b>METHODS</b>Sixty five patients with breast cancer underwent (99)Tc(m)-MIBI scintimammography before NCT, and static planar images were taken at 10 min and 180 min after scintimammography. The clearance rate was calculated in each patient, correlation between the clearance rate and efficacy of NCT, and the disease free survival rate were analyzed.</p><p><b>RESULTS</b>The mean clearance rate of 65 patients was (17.4 ± 6.8)%. The efficacy of NCT was 86.2% (CR 4 cases, PR 52 cases, SD 8 cases, and PD 1 case), and the mean clearance rate of patients with good response or poor response of chemotherapy were (15.5 ± 5.0)% and (29.2 ± 3.2)%, respectively. There was a significant difference between the two groups. The average disease free survival rate in the group with low clearance rate was (75.8%, P = 0.046), significantly higher than that in the group with high clearance rate (53.1%).</p><p><b>CONCLUSION</b>Scintimammography of (99)Tc(m)-MIBI may be used to evaluate the efficacy and prognosis of NCT for patients with operable breast cancer.</p>

Enrichment of breast cancer stem cells using a keratinocyte serum-free medium / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Keratinocyte serum-free medium (K-SFM) is a defined medium used to support the growth of primary keratinocytes and embryonic stem cell. The aim of this research was to optimize enrichment of breast cancer stem cells (CSCs) using K-SFM.</p><p><b>METHODS</b>A K-SFM was used to enrich CSCs from two breast cancer cell lines and a primary culture of breast cancer. RPMI-1640 supplemented with 10% fetal calf serum (FCS) was used as a control. CSCs were identified with flow cytometry using CD44(+)/CD24(-) as molecular markers. The expression of a variety of CSC markers (Oct-4, ABCG2, Nanog, N-cadherin, and E-cadherin) was analyzed with real-time PCR.</p><p><b>RESULTS</b>Much higher percentage of CSCs was achieved with K-SFM: 17.3% for MCF-7 cells, 17.4% for SKBR-3, and 20.0% for primary breast cancer culture. Less than 1% CSC was achieved using RPMI-1640 supplemented with 10% FCS. In comparison to the CSCs obtained with RPMI-1640, CSCs in the K-SFM expressed higher levels of Oct-4, ABCG2, Nanog and N-cadherin, and lower level of E-cadherin.</p><p><b>CONCLUSION</b>K-SFM is an optimal culture medium to maintain and to enrich breast CSCs.</p>

Construction of a eukaryotic expression vector expressing human IFN-gamma and its inhibitory effect on HBV replication in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the inhibitory effect of a eukaryotic expression vector expressing human IFN-gamma (pcDNA3.1- IFN-gamma) on HBV replication in hepG2.2.15 cells.</p><p><b>METHODS</b>The eukaryotic expression vector expressing human IFN-gamma was constructed using PCR and gene recombination technique. hepG2.2.15 cells were transfected with pcDNA3.1-IFN-gamma and the culture supernatant was collected to determine the expression of IFN-gamma protein by ELISA. The HBV DNA copies and the concentration of HBeAg and HBsAg were measured by fluorescence real-time PCR and ELISA kit, respectively.</p><p><b>RESULTS</b>Compared with that of negative control and blank 2.2.15 cells, the concentration of HBeAg in the supernatant of 2.2.15 cells transfected with pcDNA3.1- IFN-gamma were decreased by 49%, and HBsAg concentration was lowered by 35% and 33%, respectively. A significant decrease of HBV DNA copies was observed in pcDNA3.1- IFN-gamma-transfected cells in comparison with the two control cells. No significant differences were noted in all the results between the two control groups.</p><p><b>CONCLUSION</b>We have successfully constructed the eukaryotic expression vector expressing human IFN-gamma, which provides a basis for anti-HBV gene therapy using human IFN-gamma.</p>

Expression of transient receptor potential channel 4 in striatum and hippocampus of rats is increased after focal cerebral ischemia / 生理学报

This paper was designed in middle cerebral artery occlusion (MCAO) model of rats, to explore the role of transient receptor potential channel 4 (TRPC4) as Ca(2+) selective channel by detecting the changes of the expression of TRPC4 in different parts of cerebral tissues under the condition of focal cerebral ischemia. The rats were sacrificed after MCAO surviving time 6 h, 12 h, 1 d, 3 d. As determined by Western blot, the expressions of TRPC4 in striatum and hippocampus of 12 h, 1 d, 3 d groups were significant higher than that in the control group (P<0.05). Immunohistochemical staining showed that the TRPC4 immunoreactive substances were present in the membrane of neurons. Compared with the control group, immunostaining positive cells increased in hippocampus and striatum of cerebral ischemia groups. The TRPC4 immunostaining positive cells increased significantly in 1d-group and 3d-group (P<0.05). It suggests that as a Ca(2+) selective channel, the variance of the expression of TRPC4 may play a role in acute and delayed neuronal injury in focal cerebral ischemia.

The expression of nestin in ischemia-injured brain of adult rat / 生理学报

Immunohistochemistry and double immunofluorescent labeling techniques combined with confocal laser scanning microscope analysis were used to investigate the characteristic spatial induction profile of nestin following a transient middle cerebral artery occlusion in adult rat brain. The results showed that nestin was induced in ischemic core at 1 day after reperfusion. In addition to ischemic core, the expression of nestin increased in peri-ischemic I, II and III regions at 3 days and 1 week, then it decreased and narrowed along the rim of ischemic core 2 weeks after reperfusion. Double immunofluorescent labeling showed that nestin positive cells were mostly co-stained with GFAP,a astrocyte marker, in peri-ischemic I region 3 days after reperfusion. At 2 weeks, however nestin cells showed a long process and the cells double stained with nestin and NSE,a neuonal specific marker,increased in the ischemic brain. The results suggest that cerebral ischemia induces nestin expression in damaged neurons which might favor the neuroprotection against ischemic damage.