Investigation of effective components and action mechanism of Yiguanjian in treatment of liver fibrosis based on network pharmacology

BACKGROUND

Traditional Chinese medicine compounds are characterized by the comprehensive adjustment of multiple components and show unique advantages in the prevention and treatment of liver fibrosis. Yiguanjian (YGJ) is a famous prescription for nourishing Yin to soothe the liver, which can improve the symptoms of liver fibrosis, and understanding its anti-liver fibrosis mechanism can promote its development and use.

AIM

To explore the mechanism of YGJ in the treatment of liver fibrosis through network pharmacology and to experi-mentally validate the initial results obtained.

METHODS

Components of YGJ and potentially targeted proteins were downloaded from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. The targets of liver fibrosis were accessed from GeneCard and OMIM databases. STRING database was utilized to construct a protein-protein interaction (PPI) network based on the components of YGJ and the targets of liver fibrosis. The PPI network was subjected to random walk with restart (RWR) to obtain key genes, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed based on the DAVID database. For animal experimental validation, eighteen SD rats were randomly assigned to a normal group, a model group, and a YGJ group. The rats in the model group and YGJ group were intraperitoneally injected with 50% CCl₄ olive oil solution for 6 wk to induce liver fibrosis, and rats in the normal group were intraperitoneally injected with the same amount of olive oil solution. Then, the rats of the YGJ group were given YGJ decoction (6.67 g/kg) daily for 4 weeks. Meanwhile, rats in the other groups were given distilled water. Blood and liver samples were collected, and the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the serum of rats were detected with an automated analyzer. Pathological changes in liver tissue were observed by hematoxylin-eosin (HE) and Masson staining. Western blot and qRT-PCR were used to detect the expression of key proteins and genes in the liver.

RESULTS

A total of 52 components and 186 potential targets of YGJ were obtained, and 1080 targets of liver fibrosis were screened. The top 10 genes with the high-affinity scores to the drug targets were STAT6, SRC, MAPK3, STX1A, EP300, STAT3, PLG, CTNNB1, CDKN1B, and CANX. The top 50 genes were mainly enriched in response to PI3K- Akt signaling pathway and FoxO signaling pathway, etc. In CCl4-induced liver fibrosis rats, YGJ decoction could significantly improve liver lesions and reduce fibrosis. YGJ decoction could reduce α-SMA expression, promote the expression of phosphorylated STAT6, increase the protein expression of PPAR-γ and CD163 and the mRNA expression of Arg-1, CD206, and CD163, and inhibit the gene expression of IL-6.

CONCLUSION

The therapeutic effect of YGJ decoction for liver fibrosis involves multiple components and multiple pathways, including the STAT6/PPAR-γ pathway.

Preventive effects of the Rehmannia glutinosa Libosch and Cornus officinalis Sieb herb couple on chronic kidney disease rats via modulating the intestinal microbiota and enhancing the intestinal barrier

CKD is a clinical syndrome with slow development and gradual deterioration of renal function. At present, modern medicine still lacks an ideal treatment method for this disease, while TCM has accumulated rich clinical experience in the treatment of CKD, which can effectively improve renal function and delay renal failure, and has unique advantages. RC is widely used in clinical practice to treat CKD, especially the “Kidney-Yin” deficiency syndrome. However, the compatibility mechanisms responsible for its effects in experimental studies, including preclinical and clinical research studies, are still not fully understood. Adenine-induced CKD rats were used to investigate the preventive effect of RC on CKD rats. Based on the high-throughput 16S rRNA gene sequencing results from Illumina, we discussed the intestinal flora abundance in rats in different treatment groups. According to a PCA and a PCoA based on a distance matrix, there was a clear separation of gut microbiome profiles between normal rats and model rats in terms of beta diversity. The abundance of Firmicutes in CKD rats was relatively increased, while that of Bacteroidetes was decreased. It is clear that the plot for the RC group was closer to that of the normal group, suggesting that the RC group had higher similarities among bacterial members with N rats. Ussing chamber, Western blot, and PCR assays were used to investigate the effects of RC on intestinal barrier function and its molecular mechanism in model animals. The results indicated that the protein expressions of ZO-1, claudin-1, and occludin-1 were decreased significantly in chronic kidney disease rats with the induction of adenine. With the treatment of RG, CO, and RC, the intestinal barrier was repaired due to the upregulated expressions of the aforementioned proteins in CKD rats. Based on our findings, RC appears to strengthen the intestinal barrier and modulate gut microbiota in adenine-induced CKD rats. This project revealed the compatibility mechanism of RC in regulating the intestinal microecology and barrier function to intervene in CKD and provided the basis and ideas for the clinical application of RC and the development of innovative drugs for CKD.

An optical neural chip for implementing complex-valued neural network

Complex-valued neural networks have many advantages over their real-valued counterparts. Conventional digital electronic computing platforms are incapable of executing truly complex-valued representations and operations. In contrast, optical computing platforms that encode information in both phase and magnitude can execute complex arithmetic by optical interference, offering significantly enhanced computational speed and energy efficiency. However, to date, most demonstrations of optical neural networks still only utilize conventional real-valued frameworks that are designed for digital computers, forfeiting many of the advantages of optical computing such as efficient complex-valued operations. In this article, we highlight an optical neural chip (ONC) that implements truly complex-valued neural networks. We benchmark the performance of our complex-valued ONC in four settings: simple Boolean tasks, species classification of an Iris dataset, classifying nonlinear datasets (Circle and Spiral), and handwriting recognition. Strong learning capabilities (i.e., high accuracy, fast convergence and the capability to construct nonlinear decision boundaries) are achieved by our complex-valued ONC compared to its real-valued counterpart.

Osteopontin attenuates early brain injury through regulating autophagy-apoptosis interaction after subarachnoid hemorrhage in rats

Aim

To determine the effect of osteopontin (OPN) on autophagy and autophagy‐apoptosis interactions after SAH.

Methods

The endovascular perforation model of SAH or sham surgery was performed in a total of 86 Sprague‐Dawley male rats. The temporal expressions of endogenous OPN and autophagy‐related proteins (Beclin 1, ATG5, LC3 II to I ratio) were measured in sham and SAH rats at different time points (3, 6, 12, 24, and 72 hours). Rats were randomly divided into three groups: Sham, SAH + Vehicle (PBS, phosphate‐buffered saline), and SAH + rOPN (5 μg/rat recombinant OPN). Neurobehavioral tests were performed 24 hours after SAH, followed by the collection of brain samples for assessment of autophagy and apoptosis proteins. These tests assessed whether an autophagy‐apoptosis relationship existed on the histological level in the brain.

Results

Endogenous OPN and autophagy‐related proteins all increased after SAH. rOPN administration improved neurological dysfunction, increased the expression of autophagy‐related proteins (Beclin 1, ATG5, LC3 II to I ratio) and antiapoptotic protein Bcl‐2, while decreasing the expression of proapoptotic proteins (cleaved Caspase‐3 and Bax). rOPN also regulated autophagy‐apoptosis interactions 24 hours after SAH.

Conclusion

rOPN attenuates early brain injury and inhibits neuronal apoptosis by activating autophagy and regulating autophagy‐apoptosis interactions.

[Impact of allergic airway diseases on risk of attention deficit hyperactivity disorder in school-age children]

Objective: To investigate the impact of allergic airway diseases on the risk of attention deficit hyperactivity disorder (ADHD) in school-age children. Method: Used stratified cluster sampling method, school-age children in first to sixth grade in primary schools in 9 randomly selected cities including Shanghai, Guangzhou, Xi'an, and Wuhan were enrolled in the study. Interview of parents with questionnaires, which included school-age individual and family social environment questionnaire (including history of diagnosed ADHD, allergic rhinitis, and bronchial asthma) and Children's Sleep Habits Questionnaire (CSHQ), were finished and collected during November to December in 2005.Diagnosed allergic rhinitis and asthma by specialist were independent variables and divided into following three categories as no allergic diseases (neither allergic rhinitis nor asthma), single allergic disease (allergic rhinitis or asthma), and combined allergic diseases (allergic rhinitis and asthma). Diagnosed ADHD as dependent variable, binary logistic regress model was used to analyze the risks of ADHD in school-age children. Result: Totally 23 791 questionnaires were handed out, while 22 018 were collected. The children had an average age of (8.8±1.8) years, within which 10 869 were male, and 11 021 were female. The risk ratios of ADHD were 2.197 (95%CI: 1.823-2.648) and 3.150 (95%CI: 2.082-4.760) in children with single allergic disease and combined allergic diseases separately. There was no significant difference after adjusting for the factor of sleep habits, as the risk ratios were 2.055 (95%CI: 1.683-2.508) and 3.140 (95%CI: 2.061-4.784) in children with single and combined allergic airway disease separately. Conclusion: Allergic rhinitis and bronchial asthma increased the risk of ADHD, not depending on sleep habits. Hence, allergic airway diseases could be independent risk factors of ADHD.

NUF2 is a valuable prognostic biomarker to predict early recurrence of hepatocellular carcinoma after surgical resection

Early tumor recurrence after curative surgical resection poses a great challenge to the clinical management of hepatocellular carcinoma (HCC). We conducted whole genome expression microarrays on 64 primary HCC tumors with clinically defined recurrence status and cross-referenced with RNA-seq data from 18 HCC tumors in the Cancer Genome Atlas project. We identified a 77-gene signature, which is significantly associated with early recurrent (ER) HCC tumors. This ER-associated signature shows significant enrichment in genes involved in cell cycle pathway. We performed receiver operating characteristic (ROC) analysis to evaluate the prognostic biomarker potential of these 77 genes and Pearson correlation analysis to identify 11 close clusters. The one gene with the best area under the ROC curve in each of the 11 clusters was selected for validation using reverse-transcription quantitative PCR in an independent cohort of 24 HCC tumors. NUF2 was identified to be the minimal biomarker sufficient to discriminate ER tumors from LR tumors. NUF2 in combination with liver cirrhosis could significantly improve the detection of ER tumors with an AUROC of 0.82 and 0.85 in the test and validation cohort, respectively. In conclusion, NUF2 in combination with liver cirrhosis is a promising prognostic biomarker for early HCC recurrence.

[Expression of Oct4 and Sox2 and their clinical significance in tongue squamous cell carcinoma]

Objective: To investigate Oct4 and Sox2 protein expression in tongue squamous cell carcinoma (TSCC) and the relationships between the expressions of Oct4 and Sox2 and clinical pathological characteristics and survival of patients. Methods: The paraffin imbedded tissue specimens of 51 patients with histologically confirmed TSCC were included. Immunohistochemistry was employed to detect the protein expression of Oct4 and Sox2 in 51 TSCC tissue samples. The protein expression levels of Oct4 and Sox2 and their relationships with both clinicopathological features and survival of patients with TSCC were evaluated. Results: In 51 TSCC cases,positive expressions of Oct4 and Sox2 were mainly located in the nucleus of tumor cells. The expression of Oct4 was strongly positive in 27 cases (53%), weakly positive in 16 (31%) and negative in 8 (16%), whereas that of Sox2 was strongly positive in 25 cases (49%), weakly positive in 22 (43%) and negative in 4 (8%). Oct4 and Sox2 expression levels were significantly correlated with the histological grade of TSCC (P=0.004, P=0.006, respectively), not correlated with age, gender, T stage, tobacco smoking and alcohol consumption status (P>0.05), but Oct4 expression level was significantly associated with lymph node metastasis (P=0.001). Sox2 expression level was not associated with lymph node metastasis (P>0.05). The expression of Sox2 was significantly correlated with Oct4 (P<0.001). Oct4 and Sox2 expression was associated with poor overall survival of patients with TSCC (P=0.001, P=0.002, respectively), cases with higher Oct4 and Sox2 expression had the poorest overall survival (P<0.001). Sox2 expression and lymph node metastasis were independent prognostic factors of overall survival in patients with TSCC (P=0.02, P=0.001, respectively). Conclusions: Sox2 had independent prognostic effects on overall survival, suggesting that Sox2 expression may be an usefull indicator for predicting the prognosis of patients with TSCC.

Endoscopic surgery of a sinonasal inverted papilloma: Surgical strategy, follow-up, and recurrence rate

BACKGROUND

Sinonasal inverted papilloma (SNIP) is noted for its high rate of recurrence and malignant transformation. Although many clinical studies have demonstrated the effectiveness of the endoscopic approach for SNIP, the surgical strategy has been the subject of much debate.

OBJECTIVE

To evaluate the effectiveness of the endoscopic endonasal approach in SNIP.

METHODS

A systematic review of patients with a diagnosis of SNIP and who had surgery at our institution from June 2005 to March 2013 was performed. All the patients who had postoperative follow-up for >2 years were enrolled. Each case was categorized into one of four stages as reported by Krouse. Demographic and tumor date, operative approach, complications, and recurrence rates were collected.

RESULTS

A total of 125 patients were included in this study. There were 17 patients in stage 1, 40 in stage 2, 57 in stage 3, and 11 in stage 4. The overall recurrence rate was 8.0%. There was no significant difference in recurrence among the stages (all p > 0.05). Recurrence after endoscopic endonasal approach (8.4%) and a combined endoscopic and open exposure procedure (5.6%) were not significantly different (p > 0.05). The recurrence rate was significantly (p < 0.05) higher in patients with revision (15.6%) than in patients in the primary cases (3.8%). A common site of tumor origin was recorded to be from the maxillary sinus (40.2%). Twenty percent of recurrences were observed up to 5 years after surgery.

CONCLUSION

Endoscopic surgery may be preferred for treating SNIP. The elevated recurrence rate after revision emphasized the significance of the first surgery. We encourage a follow-up period of at least 5 years.

Over-expression of the long non-coding RNA HOTTIP inhibits glioma cell growth by BRE

Background

Gliomas are the most common type of primary brain tumour in the central nervous system of adults. The long non-coding RNA (lncRNA) HOXA transcript at the distal tip (HOTTIP) is transcribed from the 5′ tip of the HOXA locus. HOTTIP has recently been shown to be dysregulated and play an important role in the progression of several cancers. However, little is known about whether and how HOTTIP regulates glioma development.

Methods

In this study, we assayed the expression of HOTTIP in glioma tissue samples and glioma cell lines using real-time polymerase chain reaction and defined the biological functions of HOTTIP using the CCK-8 assay, flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL assay) and tumour formation assay in a nude mouse model. Finally, we discovered the underlying mechanism using the Apoptosis PCR 384HT Array, Western blot, RNA immunoprecipitation (RIP) and luciferase reporter assay.

Results

HOTTIP was aberrantly down-regulated in glioma tissues and glioma cell lines (U87-MG, U118-MG, U251 and A172), and over-expression of HOTTIP inhibited the growth of glioma cell lines in vitro and in vivo. Furthermore, HOTTIP could directly bind to the brain and reproductive expression (BRE) gene and down-regulate BRE gene expression. In addition, we further verified that over-expression of the BRE gene promoted the growth of glioma cell lines in vitro. Finally, over-expression of HOTTIP significantly suppressed the expression of the cyclin A and CDK2 proteins and increased the expression of the P53 protein. However, we found that the over-expression of BRE significantly increased the expression of the cyclin A and CDK2 proteins and suppressed the expression of the P53 protein. Taken together, these findings suggested that high levels of HOTTIP reduced glioma cell growth. Additionally, the mechanism of HOTTIP-mediated reduction of glioma cell growth may involve the suppression of cyclin A and CDK2 protein expression, which increases P53 protein expression via the down-regulation of BRE.

Conclusions

Our studies demonstrated that over-expression of HOTTIP promotes cell apoptosis and inhibits cell growth in U118-MG and U87-MG human glioma cell lines by down-regulating BRE expression to regulate the expression of P53, CDK2 and Cyclin A proteins. The data described in this study indicate that HOTTIP is an interesting candidate for further functional studies in glioma and demonstrate the potential application of HOTTIP in glioma therapy.

Electronic supplementary material

The online version of this article (doi:10.1186/s13046-016-0431-y) contains supplementary material, which is available to authorized users.

[Proliferation and differentiation of endogenous neural stem cells in subventricular zone in rats after traumatic craniocerebral injury]

OBJECTIVE

To observe the time course of proliferation and differentiation of neural stem cells (NSCs) in the subventricular zone (SVZ) of rats following traumatic craniocerebral injury (TBI).

METHODS

Forty-eight SD rats were randomized into 3 groups, namely the control group without any treatment, the sham-operated group with scalp incision and preparation of a cranial window, and TBI group with craniocerebral injury induced by Feeney's method. With nestin and BrdU as two cell markers, NSE as the neuron-specific marker and GFAP as the glial cell marker, immunofluorescence assay with double labeled antibodies was performed to examine the proliferation and differentiation of endogenous NSCs in the SVZ at different time points after TBI.

RESULTS

s The numbers of cells positive for nestin/NSE, nestin/GFAP, BrdU/NSE, and BrdU/GFAP in the SVZ of the rats increased significantly after TBI. The positive cells began to increase at 1 day after TBI, reached the peak level at day 3 and became normal at day 14, showing significant differences between the time points of measurement following TBI and from the cell numbers in the control group measured at the same time points. The cells positive for nestin/ GFAP showed the most distinct increase in the SVZ of the rats with TBI.

CONCLUSION

TBI results in mobilization of the NSCs in the SVZ on the injured side to cause the proliferation and differentiation of the endogenous NSCs. The SVZ is one of the most important germinal centers of NSC proliferation and differentiation.

All-trans retinoic acid impairs the vasculogenic mimicry formation ability of U87 stem-like cells through promoting differentiation

The poor therapeutic effect of traditional antiangiogenic therapy on glioblastoma multiforme (GBM) may be attributed to vasculogenic mimicry (VM), which was previously reported to be promoted by cancer stem-like cells (SLCs). All-trans retinoic acid (ATRA), a potent reagent which drives differentiation, was reported to be able to eradicate cancer SLCs in certain malignancies. The aim of the present study was to investigate the effects of ATRA on the VM formation ability of U87 glioblastoma SLCs. The expression of cancer SLC markers CD133 and nestin was detected using immunocytochemistry in order to identify U87 SLCs. In addition, the differentiation of these SLCs was observed through detecting the expression of glial fibrillary acidic protein (GFAP), β-tubulin III and galactosylceramidase (Galc) using immunofluorescent staining. The results showed that the expression levels of GFAP, β-tubulin III and Galc were upregulated following treatment with ATRA in a dose-dependent manner. Furthermore, ATRA significantly reduced the proliferation, invasiveness, tube formation and vascular endothelial growth factor (VEGF) secretion of U87 SLCs. In conclusion, the VM formation ability of SLCs was found to be negatively correlated with differentiation. These results therefore suggested that ATRA may serve as a promising novel agent for the treatment of GBM due to its role in reducing VM formation.

Effects of γ-ray irradiation on optical absorption and laser damage performance of KDP crystals containing arsenic impurities

The effects of γ-irradiation on potassium dihydrogen phosphate crystals containing arsenic impurities are investigated with different optical diagnostics, including UV-VIS absorption spectroscopy, photo-thermal common-path interferometer and photoluminescence spectroscopy. The optical absorption spectra indicate that a new broad absorption band near 260 nm appears after γ-irradiation. It is found that the intensity of absorption band increases with the increasing irradiation dose and arsenic impurity concentration. The simulation of radiation defects show that this absorption is assigned to the formation of AsO₄⁴⁻ centers due to arsenic ions substituting for phosphorus ions. Laser-induced damage threshold test is conducted by using 355 nm nanosecond laser pulses. The correlations between arsenic impurity concentration and laser induced damage threshold are presented. The results indicate that the damage performance of the material decreases with the increasing arsenic impurity concentration. Possible mechanisms of the irradiation-induced defects formation under γ-irradiation of KDP crystals are discussed.

Diode-pumped 1988-nm Tm:YAP laser mode-locked by intracavity second-harmonic generation in periodically poled LiNbO₃

We report a diode-pumped intracavity second-harmonic generation mode-locked solid-state Tm:YAP laser operating at 1988 nm using a periodically poled congruent LiNbO3 as the nonlinear crystal. The threshold of continuous wave mode locking is 11.6 W. The maximum output power is 1.67 W, while the shortest pulse obtained is 4.7 ps at a repetition rate of 97.09 MHz.

Control of postharvest grey mould decay of nectarine by tea polyphenol combined with tea saponin

The control efficacy of tea polyphenol (TP) in combination with tea saponin (TS) against nectarine grey mould decay caused by Botrytis cinerea and the underlying mechanism were investigated. The in vitro experiments showed that both TP and TS inhibited the mycelial growth in a dose-dependent manner, and their combinations exhibited synergistic antifungal interactions with the synergistic ratios (SR) exceeding 1·5. The in vivo experiments showed that disease incidence and lesion diameter of grey mould of inoculated fruit were significantly lowered after being treated with the combination of TP and TS; furthermore, the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD), polyphenol oxidase (PPO), chitinase and β-1,3-glucanase of inoculated fruit as well as the contents of total phenolic and lignin were significantly induced, the respiration rate of inoculated fruit was significantly decreased and therefore the quality decrease was accordingly retarded. These results revealed that TP in combination with TS could control grey mould of inoculated nectarines and their mechanism of action might be attributed to their active components, the induction of defensive system and the regulation of respiration.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study demonstrates that the combination of TP and TS has exhibited synergistic antifungal interactions against Botrytis cinerea, and it suggests that their combination may be useful and effective agents for the control of nectarine grey mould decay. Such natural products therefore represent a promising alternative to synthetic fungicides in the control of nectarine postharvest diseases.

Anti-inflammatory and immunomodulatory mechanisms of mesenchymal stem cell transplantation in experimental traumatic brain injury

Background

Previous studies have shown beneficial effects of mesenchymal stem cell (MSC) transplantation in central nervous system (CNS) injuries, including traumatic brain injury (TBI). Potential repair mechanisms involve transdifferentiation to replace damaged neural cells and production of growth factors by MSCs. However, few studies have simultaneously focused on the effects of MSCs on immune cells and inflammation-associated cytokines in CNS injury, especially in an experimental TBI model. In this study, we investigated the anti-inflammatory and immunomodulatory properties of MSCs in TBI-induced neuroinflammation by systemic transplantation of MSCs into a rat TBI model.

Methods/results

MSCs were transplanted intravenously into rats 2 h after TBI. Modified neurologic severity score (mNSS) tests were performed to measure behavioral outcomes. The effect of MSC treatment on neuroinflammation was analyzed by immunohistochemical analysis of astrocytes, microglia/macrophages, neutrophils and T lymphocytes and by measuring cytokine levels [interleukin (IL)-1α, IL-1β, IL-4, IL-6, IL-10, IL-17, tumor necrosis factor-α, interferon-γ, RANTES, macrophage chemotactic protein-1, macrophage inflammatory protein 2 and transforming growth factor-β1] in brain homogenates. The immunosuppression-related factors TNF-α stimulated gene/protein 6 (TSG-6) and nuclear factor-κB (NF-κB) were examined by reverse transcription-polymerase chain reaction and Western blotting. Intravenous MSC transplantation after TBI was associated with a lower density of microglia/macrophages and peripheral infiltrating leukocytes at the injury site, reduced levels of proinflammatory cytokines and increased anti-inflammatory cytokines, possibly mediated by enhanced expression of TSG-6, which may suppress activation of the NF-κB signaling pathway.

Conclusions

The results of this study suggest that MSCs have the ability to modulate inflammation-associated immune cells and cytokines in TBI-induced cerebral inflammatory responses. This study thus offers a new insight into the mechanisms responsible for the immunomodulatory effect of MSC transplantation, with implications for functional neurological recovery after TBI.

MicroRNA-107 inhibits U87 glioma stem cells growth and invasion

Glioma stem cells (GSCs) are thought to be critical for resistance to radiotherapy and chemotherapy and for tumor recurrence after surgery in glioma patients. Identification of new therapeutic strategies that can target GSCs may thus be critical for improving patient survival. MicroRNAs (miRNAs) are small non-coding RNAs that function as tumor suppressors or oncogenes. In this study, we confirmed that miR-107 was down-regulated in GSCs. To investigate the role of miR-107 in tumorigenesis of GSCs, a lentiviral vector over-expressing miR-107 in U87GSCs was constructed. We found that over-expression of miR-107 suppressed proliferation and down-regulated Notch2 protein and stem cell marker (CD133 and Nestin) expression in U87GSCs. Furthermore, enhanced miR-107 expression significantly inhibited U87GSC invasion and reduced matrix metalloproteinase-12 expression. miR-107 also suppressed U87GSCs xenograft growth in vivo. These findings suggest that miR-107 is involved in U87GSCs growth and invasion and may provide a potential therapeutic target for glioma treatment.

P53-induced microRNA-107 inhibits proliferation of glioma cells and down-regulates the expression of CDK6 and Notch-2

MicroRNAs (miRNAs) are small noncoding RNAs that function as tumor suppressors or oncogenes. MicroRNA-107 (miR-107), a transcriptional target of p53, is deregulated in many cancer cell lines. Here, we showed that miR-107 is down-regulated in glioma tissues and cell lines, in particular, p53-mutated U251 and A172. Transfection of wild-type p53 into these cells stimulated miR-107 expression. To investigate the role of miR-107 in tumorigenesis, we constructed a lentiviral vector overexpressing miR-107. Notably, miR-107 inhibited proliferation and arrested the cell cycle at the G0-G1 phase in glioma cells. Transduction of Lenti-GFP-miR-107 into glioma cells inhibited CDK6 and Notch-2 protein expression. Our findings collectively demonstrate that p53-induced miR-107 suppresses brain tumor cell growth and down-regulates CDK6 and Notch-2 expression, supporting its tumor suppressor role and utility as a target for glioma therapy.

Passive immunization with tenascin-R (TN-R) polyclonal antibody promotes axonal regeneration and functional recovery after spinal cord injury in rats

Tenascin-R (TN-R) is a neural specific protein and an important molecule involved in inhibition of axonal regeneration after spinal cord injury (SCI). Here we report on rabbit-derived TN-R polyclonal antibody, which acts as a TN-R antagonist with high titer and high specificity, promoted neurite outgrowth and sprouting of rat cortical neurons cultured on the inhibitory TN-R substrate in vitro. When locally administered into the lesion sites of rats received spinal cord dorsal hemisection, these TN-R antibodies could significantly decrease RhoA activation and improve functional recovery from corticospinal tract (CST) transection. Thus, passive immunotherapy with specific TN-R antagonist may represent a promising repair strategy following acute SCI.

The characterization of IL-17A expression in patients with chronic rhinosinusitis with nasal polyps

BACKGROUND

Interleukin (IL)-17A, mainly produced by Th17 cells, was previously described as an inflammatory cytokine that induces a profile of proinflammatory cytokines, chemokines, and metalloproteinases. Recent studies have revealed that IL-17 is correlated with inflammatory lung disorders by triggering an accumulation of neutrophils. More recently, we have shown that the expression of IL-17 may be involved in the development of nasal polyps (NPs). Here, we describe the characterization of IL-17 expression in patients with chronic rhinosinusitis with nasal polyps (CRSwNPs) from northeast China.

METHODS

Histopathological observations and immunohistochemical (IHC) staining for IL-17, IL-17RD, myeloperoxidase, and CD68 were performed on 52 specimens (42 NPs and 10 specimens of middle turbinate as normal control). Double IHC staining was performed to determine which cells expressed IL-17. The serum expression levels of IL-17 were determined by ELISA and the mRNA expression of IL-17 and Th17 cells transcription factor retinoid acid-related orphan receptor C (RORc) was determined by real-time quantitative polymerase chain reaction.

RESULTS

42.9% of CRSwNP specimens presented eosinophilic inflammation; 35.7% of CRSwNP specimens presented neutrophilic inflammation. Relatively higher mRNA expression levels of IL-17 and RORc were seen in CRSwNPs compared with the controls. A marked increase of IL-17 and IL-17RD proteins (p < 0.01) were seen in CRSwNP group. The expression levels of IL-17 and RORc did not differ between eosinophilic and noneosinophilic CRSwNPs (p > 0.05). However, high expression levels of IL-17RD were seen in noneosinophilic CRSwNPs compared with eosinophilic CRSwNPs (p < 0.05). The serum expression of IL-17 in CRSwNP patients was similar to healthy controls. The IL-17 expressing cells mainly were the macrophages as shown by double IHC staining.

CONCLUSION

Chinese CRSwNP patients showed an enhanced Th17 response regardless of eosinophilic or noneosinophilic inflammation. IL-17 may be involved in the development of NPs through its local immune modulation.

Overexpression of interleukin-l7 in tumor-associated macrophages is correlated with the differentiation and angiogenesis of laryngeal squamous cell carcinoma

BACKGROUND

Interleukin-l7 (IL-17), which exerts strong pro-inflammatory effects, has emerged as an important mediator in inflammation-associated cancer. The aim of this study was to clarify the relationship between IL-17 and tumor associated macrophages (TAMs), and the correlation of the microvessel density in the development of laryngeal squamous cell carcinoma (LSCC).

METHODS

Histopathological observations and immunohistochemistry staining for IL-17, CD68, and CD34 were performed on 72 specimens (32 cases of LSCC, 20 cases of adjacent tissues of carcinoma as controls, and 20 cases of chronic hypertrophic laryngitis). Double immunohistochemical staining was done to determine which cells expressed IL-17. Real-time quantitative PCR determined the mRNA expression of IL-17. ELISA was used to detect the expression of the serum level of IL-17 in the three groups.

RESULTS

The inflammation response had increased in LSCC. Overexpression of IL-17 and CD68 protein were seen in LSCC (P < 0.01). The expression of IL-17 was different between well and poorly differentiated LSCC (P < 0.01). The IL-17 expressing cells were mainly located in macrophages (CD68(+)/IL17(+)) as demonstrated by double immunohistochemical staining. IL-17 expression significantly correlated with high microvessel density (CD34(+)) in LSCC (P < 0.05). Relatively higher mRNA expression levels of IL-17 were seen in LSCC compared to the controls (P < 0.05). The serum expression of IL-17 was similar among the three groups (P > 0.05).

CONCLUSION

IL-17 was expressed by TAMs, and IL-17 may significantly correlate to the differentiation and angiogenesis in the development of LSCC.

Anti-glioma response of autologous T cells stimulated by autologous dendritic cells electrofused with CD133+ or CD133- glioma cells

Glioma, the most common tumor of the central nervous system (CNS), currently results in a high rate of morbidity and mortality. The expression of CD133, a stem-like cell marker expressed in the glioma cells, is believed to lead to tumorigenesis in the human brain. Thus, it is necessary to find a proper method to specifically kill the CD133(+) glioma cells. Dendritic cell (DC)/tumor hybrids are proven to be able to induce an effective immune response, leading to killing of glioma cells in vitro. We isolated CD133(+) cells from a population of primary glioma cells, and cultured autologous DCs and T cells at the same time. Next, we electrofused the DCs with the CD133(+) glioma cells and with CD133- ones, in order to explore a new strategy for glioma therapy. We then exposed the T cells to five separate groups of cells: DC/CD133(+) hybrids, DC/CD133(-) hybrids, DCs alone, unsorted glioma cells alone and mixed DCs-glioma cells. A cytotoxicity assay showed that T cells stimulated by either type of hybrid were able to kill cultured autologous glioma cells significantly more effectively than those stimulated by the other three cell types (P<0.05). The amounts of IFN-γ secreted by T cells stimulated by the two types of fused cells were obviously increased compared to those stimulated by the other three cell types (P<0.05). However, no significant differences were noted between the effects of the two hybrids, neither in the cytotoxicity assay nor in the IFN-γ release assay (P>0.05). Therefore, both DC/CD133(+) and DC/CD133(-) hybrids can cause significant T cell immune responses in vitro. There were no significant differences between the immune responses caused by the two types of hybrids.

Comparison of transdifferentiated and untransdifferentiated human umbilical mesenchymal stem cells in rats after traumatic brain injury

Transdifferentiated and untransdifferentiated mesenchymal stem cells (MSCs) have shown therapeutic benefits in central nervous system (CNS) injury. However, it is unclear which would be more appropriate for transplantation. To address this question, we transplanted untransdifferentiated human umbilical mesenchymal stem cells (HUMSCs) and transdifferentiated HUMSCs (HUMSC-derived neurospheres, HUMSC-NSs) into a rat model of traumatic brain injury. Cognitive function, cell survival and differentiation, brain tissue morphology and neurotrophin expression were compared between groups. Significant improvements in cognitive function and brain tissue morphology were seen in the HUMSCs group compared with HUMSC-NSs group, which was accompanied by increased neurotrophin expression. Moreover, only few grafted cells survived in both the HUMSCs and HUMSC-NSs groups, with very few of the cells differentiating into neural-like cells. These findings indicate that HUMSCs are more appropriate for transplantation and their therapeutic benefits may be associated with neuroprotection rather than cell replacement.

Molecular targeting of malignant glioma cells with an EphA2-specific immunotoxin delivered by human bone marrow-derived mesenchymal stem cells

Immunotoxins have shown great promise as an alternative treatment for brain malignancies such as gliomas, but their failure to penetrate into the tumor mass remains a major problem. Mesenchymal stem cells exhibit tropism to tumor tissue and may serve as a cellular vehicle for the delivery and local production of antitumor agents. In this study, we used human bone marrow-derived mesenchymal stem cells (hMSCs) as a vehicle for the targeted delivery of EphrinA1-PE38, a very specific immunotoxin against the EphA2 receptor that is overexpressed in gliomas. hMSCs were transduced with adenovirus to express secretable EphrinA1-PE38. Our invitro assays confirmed the expression, release and selective killing effect of the immunotoxin produced by hMSCs. Furthermore, the intratumoral injection of engineered hMSCs was effective at inhibiting tumor growth in a malignant glioma tumor model. These results indicate that gene therapy utilizing EphrinA1-PE38-secreting hMSCs may provide a novel approach for the local treatment of malignant gliomas.

Cellular immunologic response to primary cryoablation of C6 gliomas in rats

The immunological consequences of cryoablation for gliomas are largely unknown. cryoablation is an attractive therapeutic option for tumors due to its minimally invasive nature. cryoablation is also potentially immunogenic. With an aim to explore changes in cellular immunity following argon-helium cryosurgery, we established Wistar rat models bearing subcutaneous C6 glioma and divided the rats into the normal control (30 rats), sham-operated (33 rats), surgical resection (30 rats), and cryosurgery (33 rats) groups with corresponding treatments. The tumor cell morphology was observed, and changes in the T lymphocyte subset and NK lymphocyte subset and the ratio of Th1/Th2 were assessed with flow cytometry following the cryosurgery. The results showed that subcutaneous tumor implantation was successful in all cases and this was confirmed histologically. Compared with surgical resection that caused significant reduction in CD3(+), CD4(+), CD14(+), CD16+56 cell percentages, cryosurgery resulted in significantly increased percentages of CD3(+), CD4(+), CD14(+), CD16+56 cells (P < 0.05) with a increase of the Th1/Th2 ratio 7 days after the operation. These results demonstrate that in addition to tumor cell destruction, cryosurgery also results in enhanced cellular immunity, suggesting the great potential of argon-helium cryosurgery in clinical management of gliomas.

A much convenient and economical method to harvest a great number of microglia

Microglia, implicating in such neuro-pathologies as brain inflammation, neurodegeneration, glioma, and neurogenesis, play an important role in central nervous system. Advanced research on microglia is crucial in exploring the neuro-pathology and neuro-physiology of these diseases, so how to culture large numbers of microglia in vitro becomes the base of a research. The wildly used method, at present, obtaining microglia from murine cannot fulfill the requirement of research, costing too much time and needing too many rats. We intend to introduce an optimized method that can harvest large quantities of microglia with high purity. Neonatal 2-3 days old Wistar rats were sacrificed and the cerebral cortices were trypsinized. We primarily cultured mixed cortical cells for 8-10 days. The microglia were harvested from the liquid supernatant; the left cells in the mixed cortical glial culture were passaged at a 1:2 density. After another 8-10 days of culture, microglia were collected again. And then, we passaged the left cells again for acquiring microglia from the third collection. We did not add additional mitogens in the experiment. At last, on average, 7.0 × 10(6) microglia were collected from one neonatal rat. By this modified method, much more microglia can be effectively and easily harvested comparing with the usual protocol before. We compared the characteristics of microglia harvested from these three passages, such as morphology, phenotype, purity, and abilities on proliferation, secretion, and phagocytosis. The cells presented typical microglia morphology, having phenotype markers of CD11b/c and CD45. The microglia from these three passages retained similar phagocytosis and secretion functions. Expanded population of microglia for investigation can be provided by this easy method in a short time with little cost and few rats.

High resolution characterization of modifications in fused silica after exposure to low fluence 355 nm laser at different repetition frequencies

We report on the characterization of modifications in fused silica after exposure to low fluence (2 J/cm2) 355 nm laser at repetition frequencies of 1 Hz, 5 Hz and 10 Hz. Synchrotron based XRF spectroscopy is employed to study concentration variation of metal inclusions in the surface layer. Positron annihilation lifetime spectroscopy is used to probe atomic size defects variation in bulk silica. FT-IR is used to characterize changes of bond length and angle of Si-O-Si covalent bond of irradiated silica. Compared to the basic frequency, the big loss of cerium and iron concentration, the size enlargement of vacancy cluster and the decrease of Si-O-Si covalent bond length after 10 Hz laser irradiation are illustrated by our data. These tiny modifications provide important data to investigate laser damage mechanism.

Correlation analysis of two serum-specific immunoglobulin E test systems and skin-prick test in allergic rhinitis patients from northeast China

BACKGROUND

Skin-prick testing (SPT) is the most common screening method for allergy evaluation. The detection of serum-specific immunoglobulin E (sIgE) is also commonly used. The sensitivity and specificity of these testing methods may vary due to type of causative allergen and type of allergic manifestation. The purpose of this study was to evaluate the correlation between two methods of measuring sIgE (AllergyScreen [Mediwiss Analytic GmbH, Moers, Germany] and ImmunoCAP [Pharmacia, Uppsala, Sweden]) and SPT for the diagnosis of allergic rhinitis (AR).

METHODS

All 216 patients who were referred to the allergist for suspected AR from June to October 2009 had SPT and the two serological tests. One hundred fifty-eight patients had a positive clinical history and a related positive SPT. The SPT was used as reference standard, and we selected three allergens (Dermatophagoides pteronyssinus, mugwort, and ragweed), which were common in fall in northeast China, to analyze the correlation of the two serum tests and SPT.

RESULTS

Compared with the SPT, the diagnostic indexes (accuracy, sensitivity and specificity) of the AllergyScreen system and the ImmunoCAP system were 0.819 versus 0.810, 0.780 versus 0.872, and 0.862 versus 0.741, respectively. The accuracy was similar between the two systems (p > 0.05). The ImmunoCAP system method had a higher sensitivity (p < 0.01). The AllergyScreen system had a higher specificity (p < 0.01).

CONCLUSION

These data support that the AllergyScreen system and ImmunoCAP system can identify potentially significant allergens in the diagnosis of AR in patients from northeastern China.

[Survey on clinical characteristics of pediatric allergic rhinitis]

OBJECTIVE

To investigate the clinical symptom, precipitating factor, associated symptom, family history and life quality of pediatric patients with allergic rhinitis, and to analyze the characteristic of clinical symptoms.

METHODS

A questionnaire survey on pediatric AR patients since June 2008 to June 2010, one hundred and forty-eight pediatric AR patients were divided into 2 groups, group A (n = 43) included children aged from 3.2 to 6.0, group B (n = 105) included children aged from 6.1 to 14.8. The severity degree of clinical symptom was assessed by visual analogue scale.

RESULTS

Preschool age children had more severe rhinocleisis, more severe cough and less rhinorrhea than school age children (χ(2) value were 29.194, 12.277 and 16.904, respectively, P < 0.05). According to the classification criteria of ARIA 2008, preschool children had more mild intermittent AR and less moderate-severe persistent AR than school age children (χ(2) value were 20.370 and 24.546, P < 0.05). The precipitating factor of common cold, fitment, climate, environment factors were 22.3% (33/148), 5.4% (8/148), 16.2% (24/148), 3.4% (5/148), the others was 4.7% (7/148), no obvious precipitating factor was 48.0% (71/148). The rate of parent or parents who had allergic disease history was 11.5% (17/148). Quality of sleep that 66.2% (98/148) were upset and 62.2% (92/148) had no cathexis.

CONCLUSIONS

The preschool children have different clinical symptom characteristic from the school age children, and we got some clinical data of pediatric AR patients, those were beneficial to the diagnose and therapy of pediatric AR. The clinical data obtained in this study from pediatric AR patients are beneficial to the diagnosis and therapy of pediatric AR.

Human umbilical vein-derived dopaminergic-like cell transplantation with nerve growth factor ameliorates motor dysfunction in a rat model of Parkinson's disease

Mesenchymal stem cells are capable of differentiating into dopaminergic-like cells, but currently no report has been available to describe the induction of human umbilical vein mesenchymal stem cells (HUVMSCs) into dopaminergic-like cells. In this study, we induced HUVMSCs in vitro into neurospheres constituted by neural stem-like cells, and further into cells bearing strong morphological, phenotypic and functional resemblances with dopaminergic-like cells. These HUVMSC-derived dopaminergic-like cells, after grafting into the brain of a rat model of Parkinson's disease (PD), showed a partial therapeutic effect in terms of the behavioral improvement. Nerve growth factor was reported to improve the local microenvironment of the grafted cells, and we therefore further tested the effect of dopaminergic-like cell grafting combined with nerve growth factor (NGF) administration at the site of cell transplantation. The results showed that NGF administration significantly promoted the survival of the grafted cells in the host brain and enhanced the content of dopaminergic in the local brain tissue. Behavioral test demonstrated a significant improvement of the motor function of the PD rats after dopaminergic-like cell grafting with NGF administration as compared with that of rats receiving the cell grafting only. These results suggest that transplantation of the dopaminergic-like cells combined with NGF administration may represent a new strategy of stem cell therapy for PD.

Effects of differentiated versus undifferentiated adipose tissue-derived stromal cell grafts on functional recovery after spinal cord contusion

Controversies exist concerning the need for mesenchymal stromal cells (MSCs) to be transdifferentiated prior to their transplantation. In the present study, we compared the results of grafting into the rat contused spinal cord undifferentiated, adipose tissue-derived stromal cells (uADSCs) versus ADSCs induced by two different protocols to form differentiated nervous tissue. Using Basso, Beattie, and Bresnahan scores and grid tests, we found that three cell-treated groups, including uADSCs-treated, dADSCs induced by Protocol 1 (dADSC-P1)-treated, and dADSCs induced by Protocol 2 (dADSC-P2)-treated groups, significantly improved locomotor functional recovery in SCI rats, compared with the saline-treated group. Furthermore, functional recovery was better in the uADSC-treated and dADSC-P2-treated groups than in the dADSC-P1-treated group at week 12 postinjury (P < 0.05 for dADSC-P1 group vs. uADSCs or dADSC-P2 groups). Although both protocols could induce high percentages of cells expressing neural markers in vitro, few BrdU-labeled cells survived at the injury sites in the three cell-treated groups, and only a small percentage of BrdU-positive cells expressed neural markers. On the other hand, the number of NF200-positive axons in the uADSC-treated and dADSC-P2-treated groups was significantly larger than those in the dADSC-P1-treated and saline-treated control groups. Our results indicate that ADSCs are able to differentiate into neural-like cells in vitro and in vivo. However, neural differentiated ADSCs did not result in better functional recovery than undifferentiated ones, following SCI. In vitro neural transdifferentiation of ADSCs might therefore not be a necessary pretransplantation step. Furthermore, cellular replacement or integration might not contribute to the functional recovery of the injured spinal cord.

[Prokaryotic expression, purification of human LINGO-1(aa76-319) and preparation of its polyclonal antibody]

OBJECTIVE

To express and purify the fusion protein of extracellular domain of human Ig domain-containing, neurite outgrowth inhibitor (Nogo) receptor-interacting protein-1 (LINGO-1(aa76-319)) in prokaryotic cells and prepare the rabbit anti-LINGO-1 polyclonal antibody (pAb).

METHODS

The 732 bp DNA sequence of hLINGO-1(aa76-319) was obtained from pCMV-SPORT6 by PCR and inserted into pET30a(+) plasmid to construct the prokaryotic expression plasmid pET30a(+)-hLINGO-1(aa76-319), which was subsequently transformed into E.coli. The target fusion protein was expressed with IPTG induction and purified by Ni(2+)-NTA affinity chromatography column. The antiserum against hLINGO-1(aa76-319) was obtained from the rabbits immunized with hLINGO-1(aa76-319), and the titer of the pAb was determined using enzyme linked immunosorbent assay (ELISA) and its specificity identified using Western blotting.

RESULTS

The prokaryotic expression plasmid pET30a(+)-hLINGO-1(aa76-319) was constructed successfully. Efficient expression of the target fusion protein was achieved with IPTG induction at the optimal concentration of 0.4 mmol/L and culture temperature at 37 degrees celsius; for 2.5 h. The hLINGO-1(aa76-319) fusion protein was effectively expressed in E.coli as inclusion bodies, and the soluble protein was obtained through denaturation and refolding procedures, and the purified fusion protein showed a purity above 90%. The titer of the anti-hLINGO-1(aa76-319) pAb obtained by immunizing the rabbits with the purified protein reached 1:1.6x10(6), and Western blotting confirmed its good specificity.

CONCLUSION

The fusion protein hLINGO-1(aa76-319) with high purity has been obtained and the anti-hLINGO-1(aa76-319) pAb obtained shows a high titer and good specificity, which provide important experimental basis for further functional investigation of LINGO-1.

Human Wharton's jelly cells can be induced to differentiate into growth factor-secreting oligodendrocyte progenitor-like cells

Human Wharton's jelly-derived mesenchymal stromal cells (hWJ-MSCs) are capable of differentiating into neural and astroglia-like cell types. However, a reliable means of inducing the selective differentiation of hWJ-MSCs into oligodendrocyte progenitor cells (OPCs) in vitro has not yet been established. In this study, the OPC-like differentiation of hWJ-MSCs was characterized using and immunoblotting. The hWJ-MSC-derived OPC-like cells were able to secrete nerve growth factors and promote neurite outgrowth in vitro. These results show that hWJ-MSCs can be induced to differentiate into cells with the morphologic, phenotypic and functional characteristics of OPC-like cells.

Cografted Wharton's jelly cells-derived neurospheres and BDNF promote functional recovery after rat spinal cord transection

An animal model of transected spinal cord injury (SCI) was used to test the hypothesis that cografted human umbilical mesenchymal stem cells-derived neurospheres (HUMSC-NSs) and BDNF can promote morphologic and functional recoveries of injured spinal cord. In vitro, HUMSC-NSs terminally differentiated into higher percentages of cells expressing neuronal markers: beta-tubulin III and MAP2ab by the supplement with BDNF. Following grafted into injured spinal cord, very few grafted cells survived in the HUMSC-NSs + BDNF-treated (<3%) and HUMSC-NSs-treated (<1%) groups. The survived cells were differentiated into various cells, which were confirmed by double staining of BrdU and neural or glia markers. In comparison, more grafted cells in the HUMSC-NSs + BDNF group transformed into mature neural-like cells, while more grafted cells in the HUMSC-NSs group transformed into oligodendrocyte-like cells. HUMSC-NSs + BDNF-treated group had more greatly improved BBB scores, compared with HUMSC-NSs-treated and medium-treated groups. Additionally, axonal regeneration showed significant improvement in rats receiving HUMSC-NSs + BDNF, compared with HUMSC-NSs-treated and medium-treated groups, as demonstrated by the NF-200-positive staining and Fluorogold (FG) retrograde tracing study. Lastly, a significant reduction in the percentage cavitation was seen in the two cell-treated groups compared with medium control group. These results means BDNF could promote the neural differentiation of HUMSC-NSs in vitro and in vivo. However, cellular replacement is unlikely to explain the improvement in functional outcome. The functional recovery might more rely on the axonal regeneration and neuroprotective action that active by the grafted cells. Cografted HUMSCs and BDNF is a potential therapy for SCI.

[Culture and identification of neural stem cells derived from the subventricular zone of adult mice]

OBJECTIVE

To establish a method for culturing and identifying neural stem cells (NSCs) derived from the subventricular zone (SVZ) in adult mice.

METHODS

NSCs were isolated from the SVZ of adult mouse brain and cultured in serum-free medium. Cell cloning and BrdU incorporation were performed to identify the self-renewal and proliferative capacity of the NSCs. Fluorescence immunocytochemistry was used to examine the expressions of the NSC markers nestin and SOX2, neuronal marker Tuj1, astrocyte marker GFAP and oligodendrocyte marker NG2. The expressions of nestin and SOX2 were further examined by Western blotting and RT-PCR.

RESULTS

NSCs with self-renewal and proliferative capacity were obtained from the SVZ of adult mice and grown as floating neurospheres. The NSCs expressed nestin and SOX2 and could differentiated into Tuj1-positive neurons, GFAP-positive astrocytes and NG2-positive oligodendrocytes.

CONCLUSION

This method allows simple and stable culture of NSCs from the SVZ of adult mice.

Beneficial effect of autologous transplantation of bone marrow stromal cells and endothelial progenitor cells on cerebral ischemia in rabbits

We tested the therapeutic effect of autologous transplanted bone marrow stromal cells (BMSCs) and endothelial progenitor cells (EPCs) on cerebral ischemia in rabbits. Rabbit permanent middle cerebral artery occlusion (MCAO) models were intravenously injected with ex vivo expanded autologous BMSCs (n = 8), EPCs (n = 8), or phosphate-buffered saline (n = 6). 14 days after the transplantation, both infusion groups witnessed a functional improvement, a decrease in the number of apoptotic cells and an increase in the microvessel density in the ischemic boundary area, as compared to vehicle-treated control group. The EPCs treated group also exhibited a diminished infarct area in comparison with the control group. Moreover, immunohistochemistry revealed that few transplanted BMSCs expressed markers for astrocytes (GFAP+) and neurons (NeuN+), and most of EPCs were capable of binding to UEA-1 lectin and were incorporated into capillaries. Our data suggest that both BMSCs and EPCs, despite differences in their action mechanism, can be functional cytoreagents for treatment of cerebral ischemia in rabbits.

A TAG1-APP signalling pathway through Fe65 negatively modulates neurogenesis

The release of amyloid precursor protein (APP) intracellular domain (AICD) may be triggered by extracellular cues through gamma-secretase-dependent cleavage. AICD binds to Fe65, which may have a role in AICD-dependent signalling; however, the functional ligand has not been characterized. In this study, we have identified TAG1 as a functional ligand of APP. We found that, through an extracellular interaction with APP, TAG1 increased AICD release and triggered Fe65-dependent activity in a gamma-secretase-dependent manner. TAG1, APP and Fe65 colocalized in the neural stem cell niche of the fetal ventricular zone. Neural precursor cells from TAG1-/-, APP-/- and TAG1-/-;APP-/- mice had aberrantly enhanced neurogenesis, which was significantly reversed in TAG1-/- mice by TAG1 or AICD but not by AICD mutated at the Fe65 binding site. Notably, TAG1 reduced normal neurogenesis in Fe65+/+ mice. Abnormally enhanced neurogenesis also occurred in Fe65-/- mice but could not be reversed by TAG1. These results describe a TAG1-APP signalling pathway that negatively modulates neurogenesis through Fe65.

[Time course of calpain activity changes in rat neurons following fluid percussion injury and the interventional effect of mild hypothermia]

OBJECTIVE

To investigate the time course of calpain activity changes in rat neurons following fluid percussion injury (FPI) under normothermia (37 degrees celsius;) and mild hypothermia (32-/+0.5) degrees celsius;.

METHODS

In vitro cultured rat neurons were subjected to FPI followed by application of mild hypothermia for intervention at different time points, and the changes in intraneuronal calpain activity following FPI and the interventional effect of mild hypothermia on calpain activity were evaluated by UV-spectrophotometry at different time points.

RESULTS

Remarkable changes occurred in calpain activity in the neurons following FPI at 37 degrees celsius;, and mild hypothermia produced obvious interventional effect on calpain activity in close relation to the timing of intervention initiation.

CONCLUSION

Intraneuronal calpain activity changes following FPI are involved in the pathological process of cellular injury, and mild hypothermia might offer protection against traumatic brain injury to some extent by regulating calpain activity. The interventional effect of mild hypothermia is associated with the timing of the intervention initiation.

[P-JAK2 and P-STAT3 protein expression and cell apoptosis following focal cerebral ischemia-reperfusion injury in rats]

OBJECTIVE

To investigate the changes in phosphorylated JAK2 and STAT3 protein expression of and cell apoptosis following focal cerebral ischemia-reperfusion injury in rats.

METHODS

A rat models of focal cerebral ischemia-reperfusion injury was established by middle cerebral artery occlusion using modified filament method. Immunohistochemistry and Western blot analysis were used to detect the expression of P-JAK2 and P-STAT3 proteins, and TUNEL assay was employed to examine the cell apoptosis.

RESULTS

P-JAK2 and P-STAT3 protein expression increased significantly after cerebral ischemia-reperfusion injury in rats. The immunoreactivity was prominent in the peripheral of the ischemic region and reached the peak level at 24 h of reperfusion, followed by slight decrement. The apoptotic cells increased obviously after cerebral ischemia-reperfusion injury, also reaching the peak level at 24 h of reperfusion.

CONCLUSION

The expression of phosphorylated JAK2 and STAT3 may be involved in the ischemic cellular events including apoptosis. JAK2/STAT3 signaling pathway plays a role in the pathophysiological process of cerebral ischemia/reperfusion cell injury and repair.

[Effect of superparamagnetic iron oxide labeling on neural stem cell survival and proliferation]

OBJECTIVE

To study the effect of superparamgnetic iron oxides (ferumoxides) on the survival and proliferation of neural stem cells (NSCs) and determine the optimal ferumoxides concentration for labeling.

METHODS

Bone marrow stromal cells (BMSCs) were obtained from rat femoral marrow and cultured in vitro to induce their differentiation into NSCs. Ferumoxides labeling of the NSCs was performed with different final concentrations of ferumoxides, and the labeling efficiency and viability of the labeled NSCs were evaluated by Prussian blue staining, MTT assay, flow cytometry and transmission electron microscope.

RESULTS

The NSCs could be effectively labeled with ferumoxides with a labeling efficiency of around 90%. Prussian blue staining showed numerous fine granules with blue staining in the cytoplasm of the labeled NSCs, and the intensity of the blue staining was in positive correlation with the ferumoxide concentration for labeling. Transmission electron microscopy of the labeled NSCs revealed the presence of numerous vesicles spreading in the cytoplasm and filled with electron-dense magnetic iron particles. The ferumoxides vesicles increased with the labeling concentration of ferumoxides, and at the final concentration exceeding 25 microg/ml, ferumoxides vesicles in the NSCs gave rise to conglomeration which hampered observation of the cellular ultrastructure by transmission electron microscope. The results of flow cytometry and MTT assay demonstrated that the cell viability, proliferation, differentiation and apoptosis of the labeled cells were affected by ferumoxides at the concentration above 25 microg/ml, but such effects could be minimal at lower concentrations.

CONCLUSION

Ferumoxides might be feasible for in vitro labeling of the NSCs with the optimal concentration of 25 microg/ml.

[Dynamic atomic force microscopic observation of the three-dimensional conformation of protein A-gold single molecule]

OBJECTIVE

To determine the three-dimensional (3D) conformation of staphylococcal protein A-gold (SPA-G) single molecule using atomic force microscope (AFM) so as to evaluate the feasibility of using this molecule for in situ labeling of the neuronal membrane protein.

METHODS

AFM was used to acquire the images of SPA-G binding to the surface of mica under physiological condition for determining the 3D conformation of the molecule.

RESULTS

SPA-G single molecule was shown to contain a characteristic structure with a chain in the shape of mirror image of the letter C, which had the dimension of 48.80 nm x 42.13 nm x 20.53 nm.

CONCLUSION

AFM provide a new means for morphological investigation of the biomacromolecule at the nanometer scale in physiological conditions, and SPA-G can be utilized for in situ labeling of the neuronal membrane receptors.

[Application of atomic force microscope in life science research]

OBJECTIVE

Atomic force microscope (AFM) is one of the most recent imaging and manipulation techniques in biological science. Among its various merits, AFM typically enables simple sample preparation, acquisition of three-dimensional images to identify single atoms under different conditions, detection of the interactive forces between two single biomolecules and their manipulation. AFM is currently applied in the research of the structure and function, at the nanometric scale, of various tissues, cells, microbes and biomolecules, and studies of the interaction between two biomolecules as well as the manipulation of some biological processes. AFM possesses the potential to become an important instrument in life science research, in spite of its current limits that require improvements such as in carbon nanotube tip, rigidity of soft biological samples and result interpretation.

[Effect of the two types of TNF-alpha on the biological functions of monocytic cell line U937]

AIM

To compare the effect of the two types of TNF-alpha, transmembrane TNF-alpha (TM-TNF-alpha) and secreted TNF-alpha (sTNF-alpha) on the biological functions of monocytic cell line U937 so as to explore the role of TM-TNF-alpha in inflammation.

METHODS

Effect of the two types of TNF-alpha on the functions of U937 cells, such as phagocytosis, accumulation of cytokines' mRNA, the level of cytoplasmic IkappaB-alpha and expression of ICAM-1, was compared by phagocytosis, RT-PCR, Western blot and FACS.

RESULTS

sTNF-alpha was found to be able to promote markedly phagocytosis by monocytic U937 cells, enhance the mRNA accumulation of cytokines, such as TNF-alpha, IL-1beta and IL-8 mRNA, induce the degradation of IkappaB-alpha and the expression of adhesion molecule ICAM-1; while TM-TNF-alpha was shown to have no effect on the functions above of U937 cells. Furthermore, it seemed TM-TNF-alpha did not have a synergic action with sTNF-alpha when U937 cells was treated with both types of TNF-alpha.

CONCLUSION

The data above shows that sTNF-alpha can activate U937 cells, while TM-TNF-alpha has no influence. It suggests that the two types of TNF-alpha may play the different role in inflammation.

[Atomic force microscopic observation of the neurons membrane in primary culture after treatment with N-Methyl-D-Asph]

OBJECTIVE

To observe the changes in three-dimensional morphology of the membrane of the cortex neurons in primary culture in response to treatment with N-Methyl-D-Asp (NMDA) and MK-801 using atomic force microscope (AFM).

METHODS

Following NMDA treatment, the changes in the membrane of the neurons fixed by glutaraldehyhyde were examined, and the protective effect of MK-801 on the neurons was also observed using an ATM at the resolution of 0.01-0.1 nm.

RESULTS

Normal neurons presented smooth membrane surface with regular undulation and densely but well arrayed protein granules. In response to NMDA treatment, the neurons were disrupted, falling into small pieces, and their membrane appeared discontinuous. MK-801 treatment increased the folds of the membrane that showed rough edges, with membrane undulation only secondary to normal condition.

CONCLUSION

AFM, with the merits of high resolution and easy sample preparation, can finely display the three-dimensional morphology of the surface of the neurons, which, after NMDA treatment, becomes disintegrated with increased bulk of the protein granules, deepened caving of the lipids, and rougher membrane surface.

Fine structure of the acinar and duct cell components in the parotid and submandibular salivary glands of the rat: a TEM, SEM, and HRSEM study

Parenchymal and stromal components of the rat parotid and submandibular glands were examined by conventional and high resolution scanning electron microscopy (HRSEM). Freeze-fractured specimens were subjected to HCl and NaOH extraction procedures to better differentiate connective tissue and cellular components. In addition, the internal three-dimensional morphology of the secretory acinar cells and duct cells was revealed by maceration with a dilute osmium tetroxide solution to selectively remove some of the cytoplasmic components. SEM and HRSEM examination of the HCl-treated samples of both glands revealed a fine filamentous network immediately surrounding each acinus. Coarser bundles of collagen that linked neighboring acini were also observed. NaOH-extracted samples selectively removed the cellular components and showed more clearly the three-dimensional structure of the connective-tissue stroma. A dense-collagenous network surrounded each lobule while more internal regions consisted of a honeycomb-like pattern of evacuated spaces previously occupied by secretory acini. These spaces were smoothened in appearance and often interconnected. Apically-located secretory granules and profiles of the rough endoplasmic reticulum and Golgi apparatus in perinuclear regions were encountered in the acinar and duct cells of macerated samples by HRSEM. In addition, a phenylephrine-induced experimental condition performed in some rats resulted in a significant increase in secretory granule size and density of the serous cells.