AMP-activated protein kinase acts as a negative regulator of high glucose-induced RANKL expression in human periodontal ligament cells

Background  It is well known that the function of periodontal ligament cells may be affected by high glucose levels. This study investigated the direct effect of high glucose on the expression of receptor activator of nuclear factor-kappa B ligand (RANKL) in human PDL (hPDL) cells. In addition, we examined whether this effect was mediated via AMPK activation.

Methods  We examined the expression of osteoprotegerin in hPDL cells cultured at different concentrations of glucose using real-time polymerase chain reaction (PCR), and Western blotting analysis. AMPK phosphorylation in hPDL cells was studied using immunoprecipitate kinase assay and Western blotting. The effect of AMPK activation on RANKL expression in hPDL cells was investigated by real-time PCR and Western blotting.

Results  High glucose levels caused an increase in RANKL mRNA and protein expression in hPDL cells. Moreover, the amount of p-AMPK and AMPK activity was lower in hPDL cells exposed to high glucose levels than in cells exposed to normal glucose levels. Suppression of AMPK by Compound C augmented RANKL expression, and AMPK activation by metformin significantly decreased RANKL expression in hPDL cells. Additionally, metformin down-regulated RANKL expression in hPDL cells exposed to high glucose via AMPK activation.

Conclusion  High glucose-induced up-regulation of RANKL could be due to decreased AMPK activity, and AMPK activation may be involved in regulating of RANKL expression in hPDL cells.

     

雌激素对人视网膜神经胶质细胞胶原块收缩的影响

目的：通过雌激素干预体外培养的人视网膜神经胶质细胞,观察雌激素对其生长、形态及对胶质细胞胶原凝胶块收缩的影响。 方法：体外培养人视网膜神经胶质细胞,用雌激素对其进行干预,观察其在数量、形态上的变化;并将人视网膜神经胶质细胞接种入胶原溶液中,制成胶质细胞胶原凝胶块,测量凝胶块的收缩程度。 结果：不同浓度雌激素对人视网膜胶质细胞的生长无明显影响,用雌激素干预的胶质细胞胶原凝胶块收缩程度较未用雌激素干预的胶质细胞胶原凝胶块收缩程度小。 结论：雌激素能够抑制胶质细胞胶原凝胶块的收缩。这有可能是女性多发的黄斑裂孔发生的原因。     

Treatment effects of captopril on non-proliferative diabetic retinopathy

Background  Diabetic retinopathy (DR) is one of the most common complications of diabetes. Angiotensin-converting enzyme inhibitor is thought to play an important role in preventing and treating retinal diseases in animal models of DR. The aim of the present study was to investigate the role of angiotensin-converting enzyme inhibitor (ACEI, captopril) in the treatment of patients with non-proliferative DR.

Methods  Three hundred and seventeen type 2 diabetic patients (88.05% of participants) without or with mild to moderate non-proliferative retinopathy were randomly divided into captopril group (n=202) and placebo group (n=115). All subjects received 24-month follow-up. General clinical examinations, including blood pressure and glycated hemoglobin, as well as comprehensive standardized ophthalmic examinations were performed. Color fundus photography and optical coherence tomography (OCT) were used to grade diabetic retinopathy and detect macular edema respectively.

Results  The levels of blood pressure and glycated hemoglobin in the two groups of patients remained within the normal range during the entire follow-up and no significant difference was found between the initial and last visits, suggesting that ACEI drugs play a protective role on the DR patients independent of its anti-blood pressure role. DR classification showed that 169 eyes (83.66%) remained unchanged and the DR grade of 33 eyes (16.34%) increased in captopril group, while 84 eyes (73.04%) remained unchanged and the grade of 31 eyes (26.96%) increased in placebo group (P=0.024). Captopril treatment improved macular edema in 55.45% eyes, which was significantly higher than the 37.39% improvement in placebo group (P=0.002). No significant difference was found in the visual acuity between the two groups (P=0.271).

Conclusion  Captopril can improve or delay the development of DR and macular edema, which can be used in the early treatment of DR patients with type 2 diabetic mellitus.

     

Specific regulator of eosinophil apoptosis: Siglec-8—new hope for bronchial asthma treatment

Objective  It is known that Siglec-8 is selectively expressed on human eosinophils at a high level and mediates eosinophil apoptosis when crosslinked with its antibody. The aim of our review is to elucidate the molecular and biological characteristic of Siglec-8 and then discuss the function and possible mechanisms of Siglec-8 in eosinophils. Thereby, we will expand our understanding to the regulation of eosinophil apoptosis, and provide important clues to the treatment of asthma and other hyper-eosinophilic diseases.

Data sources  Most articles were identified by searching of PubMed online resources using the key term Siglecs.

Study selection  Mainly original milestone articles and critical reviews written by major pioneer investigators in the field were selected.

Results  Siglec-8 is selectively expressed on human eosinophil and can specifically induce eosinophil apoptosis.

Conclusion  The restricted expression of Siglec-8 on human eosinophil and the rapid progress in understanding its role as cell signaling and activation of death receptors have made it an attractive target for treatment of asthma and other hyper-eosinophilic diseases.

     

Proteomic analysis for detecting serum biomarkers related to smoking in humans

Background  Smoking is the leading cause of death in the world. This study focused on the difference of the serum proteomic profiling between healthy smokers and nonsmokers in order to find smoking-specific serum biomarkers.

Methods  Pattern-based proteomic profiling of 100 serum samples (from 50 Chinese male smokers and 50 matched nonsmokers) was performed through magnetic bead fractionation coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis (MALDI-TOF-MS) and resulting data were statistically analyzed by Ciphergen ProteinChip software 3.0.2.

Results  We found 72 serum peaks were significantly different between smokers and nonsmokers (P <0.05). Marker peaks of mass-to-charge ratio (m/z) 3159.13, 7561.03 and 9407.32 were smoking-specific.

Conclusion  The preliminary data suggested that smoking-specific serum biomarkers could be detected in humans.

     

Rho-associated coiled kinase inhibitor Y-27632 promotes neuronal-like differentiation of adult human adipose tissue-derived stem cells

Background  Y-27632 is a specific inhibitor of Rho-associated coiled kinase (ROCK) and has been shown to promote the survival and induce the differentiation of a variety of cells types. However, the effects of Y-27632 on adult human adipose tissue-derived stem cells (ADSCs) are unclear. This study aimed to investigate the effects of Y-27632 on the neuronal-like differentiation of ADSCs.

Methods  ADSCs were isolated from women undergoing plastic surgery and cultured. ADSCs were treated with different doses of Y-27632 and observed morphological changes under microscope. The expression of nestin, neuron specific enolase (NSE) and microtubule-associated protein-2 (MAP-2) in ADSCs treated with Y-27632 was detected by immunocytochemistry and Western blotting analysis.

Results  Y-27632 had the potency to induce neuronal-like differentiation in ADSCs in a dose-dependent manner. Moreover, the differentiation induced by Y-27632 was recovered upon drug withdraw. ADSCs treated with Y-27632 expressed neuronal markers such as NSE, MAP-2 and nestin while untreated ADSCs did not express these markers.

Conclusion  Selective ROCK inhibitor Y-27632 could potentiate the neuronal-like differentiation of ADSCs, suggesting that Y-27632 could be utilized to induce the differentiation of ADSCs to neurons and facilitate the clinical application of ADSCs in tissue engineering.

     

Antiviral therapy of decompensated hepatitis B virus-related cirrhosis

Objective  To review the development, mechanism, necessity and limitation of antiviral therapy in decompensated hepatitis B virus-related cirrhosis.

Data sources  Most information was pulled from a literature search (Pubmed 2000 to 2011) using the keywords of antiviral and decompensated hepatitis B virus-related cirrhosis. Relevant book chapters were also reviewed.

Study selection  Well-controlled, prospective landmark studies and review articles on antiviral therapy in decompesated hepatitis B virus-related cirrhosis were selected.

Results  Specific antiviral agents not only control viral replication, which permits liver transplantation, but also improve liver function so significantly that patients could be removed from the transplant waiting list. However, the emergence of drug-resistant mutants can result in treatment failure. Combination therapy is a save-strategy in drug-resistant.

Conclusions  Although the treatment of end-stage liver disease is still a challenge worldwide, antiviral therapy has altered the natural history of hepatitis B patients with decompensated cirrhosis. The approval of the new generation of antivirals is opening new perspectives for finding the optimal antiviral treatment for patients with decompensated cirrhosis and preventing antiviral resistance. A combination of antivirals may be one of the future strategies for fulfilling these goals.

     

Role of microRNA-181a in the apoptosis of tubular epithelial cell induced by cisplatin 

Background  Cisplatin (DDP) is one of most effective and most commonly used therapeutic agent in treating tumors, it can accumulate in the kidney and lead to acute renal failure. MicroRNA-181a can induce cell apoptosis by suppressing the expression of Bcl-2 family. In the present study, we investigated the role of microRNA-181a in the apoptosis of tubular epithelial cell induced by DDP.

Methods  HK-2 cells were cultured, transfected with microRNA-181a inhibitor for 48 hours, and stimulated with 50 µmol/L cisplatin for 24 hours. MicroRNA-181a expression was analyzed by real time PCR, and cell apoptosis was detected by flow cytometry. Moreover, Bcl-2 and Bcl-2-associated X protein (Bax) expression were measured by Western blotting.

Results  MicroRNA-181a expression significantly down-regulated in cells transfected with microRNA-181a inhibitor, compared with that in untransfectd cells (21.19±2.01 vs. 38.87±1.97, P <0.05). Cell apoptosis induced by DDP significantly decreased in cells transfected with MicroRNA-181a inhibitor. Compared with DDP treated cells alone, Bcl-2 expression strikingly was up-regulated and Bax expression was down-regulated in cells transfected with microRNA-181a inhibitor.

Conclusion  One pathway of DDP induces apoptosis of tubular epithelial cell by suppressing Bcl-2 expression is achieved by regulating the target gene of MicroRNA-181a.

     

Effect of chronic intermittent hypoxia on theophylline metabolism in mouse liver

Background Chronic intermittent hypoxia (CIH) has been associated with abnormalities in the liver,which is the most important organ for drug metabolism.This study aimed to investigate the effect of CIH...     

Silencing of osteopontin promotes the radiosensitivity of breast cancer cells by reducing the expression of hypoxia inducible factor 1 and vascular endothelial growth factor

Background  Osteopontin (OPN) is a secreted phosphoglycoprotein (SSP) that is overexpressed in a variety of tumors and was regarded as a molecular marker of tumors. In this study, we intended to demonstrate the role of OPN in human breast cancer cell line MDA-MB-231.

Methods  Recombinant plasmid expressing small interfering RNA (siRNA) specific to OPN mRNA was transfected into MDA-MB-231 cells to generate the stable transfected cell line MDA-MB-343, and the empty plasmid tansfected cells (MDA-MB-neg) or wildtype MDA-MB-231 cells were used as control cells respectively. Expression of OPN, hypoxia inducible factor-1 (HIF-1) and vascular endothelial growth factor (VEGF) proteins was analyzed by Western blotting analysis. The radiosensitivity of cells was determined by detecting cell apoptosis, cell proliferation and cell senescence.

Results  HIF-1 and VEGF proteins in MDA-MB-343 cells were significantly downregulated upon the efficient knockdown of OPN expression under either hypoxia or normoxia environment. Moreover, expression of OPN protein was upregualted upon hypoxic culture. Stable OPN-silencing also decreased cell invasion, increased cell apoptosis and cell senescence, as well as reduced clonogenic survival, resulting in increase radiation tolerance.

Conclusions  Suppression of OPN gene expression can enhance radiosensitivity and affect cell apoptosis in breast cancer cells. OPN seems to be an attractive target for the improvement of radiotherapy.

     

Culture supernatants of breast cancer cell line MDA-MB-231 treated with parthenolide inhibit the proliferation, migration, and lumen formation capacity of human umbilical vein endothelial cells

Background  Parthenolide has been tested for anti-tumor activities, such as anti-proliferation and pro-apoptosis in recent studies. However, little is known about its role in the process of tumor angiogenesis. This study aims to investigate the effects and potential mechanisms of parthenolide on the proliferation, migration and lumen formation capacity of human umbilical vein endothelial cells.

Methods  Different concentrations of parthenolide were applied to the human breast cancer cell line MDA-MB-231 cells. After 24-hour incubation, the culture supernatants were harvested and used to treat human umbilical vein endothelial cells for 24 hours. Then an inverted fluorescence phase contrast microscope was used to evaluate the human umbilical vein endothelial cells. The secretion of vascular endothelial growth factor (VEGF), interleukin (IL)-8 and matrix metalloproteinases (MMP)-9 in the culture supernatant of the MDA-MB-231 cells was then measured with enzyme-linked immunosorbent assay (ELISA) assays.

Results  Suppression of proliferation, migration, and the lumen formation capacity of human umbilical vein endothelial cells was observed in the presence of the culture supernatants from the breast cancer cell line treated with different concentrations of parthenolide. Parthenolide decreased the levels of the angiogenic factors MMP-9, VEGF, and IL-8 secreted by the MDA-MB-231 cells.

Conclusions  Parthenolide may suppress angiogenesis through decreasing angiogenic factors secreted by breast cancer cells to interfere with the proliferation, migration and lumen-like structure formation of endothelial cells, thereby inhibiting tumor growth. It is a promising potential anti-angiogenic drug.

     

Gene delivery in peritoneal dialysis related peritoneal fibrosis research

Objective  To summarize the development of gene delivery vectors in peritoneal fibrosis research and discuss the feasibility and superiority of lentiviral vectors.

Data sources  The data in this article were collected from PubMed database with relevant English articles published from 1995 to 2011.

Study selection  Articles regarding the gene therapy in peritoneal fibrosis research using non-viral vectors, adenoviral vectors, retroviral vectors, and lentiviral vectors were selected. Data were mainly extracted from 60 articles, which are listed in the reference section of this review.

Results  Non-viral vector-mediated gene delivery (including naked DNA for ex vivo, oligonucleotides, ultrasound- contrast agent mediated naked gene delivery, etc.) and viral vector-mediated gene delivery (including adenovirus, helper-dependant adenovirus, and retrovirus vectors) have been successfully applied both in the mechanistic investigation and the potential prevention and treatment of peritoneal fibrosis.

Conclusions  Peritoneal fibrosis is a major complication of peritoneal dialysis (PD). Recently, the wide use of the gene delivery technique made it possible to access and further research peritoneal fibrosis. The use of lentiviral vector is expected to be widely used in PD research in the future due to its advantages in gene delivery.

     

Effect of peritumoral injection of boanmycin hydrochloride within temperature-sensitive in situ gel using Hep-G2 hepatoma nude mice model

Background  Boanmycin hydrochloride, a new antitumor agent, has a short half-life and fast clearance speed in vivo. The aim of this research was to investigate the effectiveness of peritumor injection of boanmycin hydrochloride within temperature-sensitive gel in situ using Hep-G2 hepatoma nude mice model.

Methods  Nude mice with human Hep-G2 tumor in right flank were randomly divided into four groups: normal saline group, in situ gel only group, boanmycin hydrochloride in situ saline group, and boanmycin hydrochloride in situ gel group, and were treated with injection of corresponding agents into peripheral tissue of the tumor. The volume of the tumor and the body weight of the mice were regularly measured, and tumor growth curve was generated. The size, internal echo, and blood flow of the tumors were observed by color Doppler ultrasonography. Histopathologic changes of the tumor after treatment were observed under both optical and transmission electron microscopy.

Results  The tumor growth was significantly inhibited by peritumoral therapy in boanmycin hydrochloride in situ gel group with the tumor inhibitory rate of 86.76%. The blood flow of the tumor was still seen in both normal saline group and in situ gel only group on color Doppler ultrasound. Punctate calcification and dotted blood flow were seen in boanmycin hydrochloride group; however, there was massive calcification and no blood flow in the tumor in the boanmycin hydrochloride in situ gel group. Large areas of necrosis and apoptotic cells were shown by microscopic observation in boanmycin hydrochloride in situ gel group.

Conclusion  Temperature-sensitive boanmycin hydrochloride in situ gel can effectively delay the release of boanmycin hydrochloride and increase its anticancer effects for liver cancer in animal model.

     

Increased expression of serum gelsolin in patients with osteosarcoma.

Background  Identification of potential serum biomarkers of osteosarcoma to aid in its early diagnosis and in the discovery of possible therapeutic targets is an area of increasing interest.

Methods  Two-dimensional difference-in-gel electrophoresis was used to assess multiple serum samples in patients with osteosarcoma. In addition, differential expression of protein biomarkers was characterized in osteosarcoma serum by using matrix-assisted desorption/ionization time-of-flight mass spectrometry coupled with database interrogation. Serum samples from four individuals with osteosarcoma and four age- and sex-matched healthy control subjects were compared.

Results  Fifty-eight significant protein spot features in the osteosarcoma sera were found. These spot features were excised, digested with trypsin, and analyzed with mass spectrometry. Gelsolin was down-regulated only in osteosarcoma. Furthermore, Western blotting and enzyme linked immunosorbent assay (ELISA) confirmed decreased levels of gelsolin in the osteosarcoma serum samples.

Conclusions  These results indicated that gelsolin might have great potential as a biomarker of osteosarcoma and as a potential target for gene therapy.

     

Clinical features and imaging findings in pulmonary capillary hemangiomatosis: report of two cases and a pooled analysis

Background  Pulmonary capillary hemangiomatosis (PCH) is a rare disease and no Chinese case has been reported yet. The disease is often misdiagnosed and its clinical characteristics are incompletely described. The aim of this study was to describe two Chinese cases and to clarify the clinical and radiographic parameters of patients with PCH.

Methods  Two PCH cases were presented and other cases were searched from the English literature. All available clinical and radiographic data were collected from 62 literature reported PCH cases. A pooled analysis of total 64 cases was made.

Results  Dyspnea and hemoptysis were the most common clinical symptoms of PCH. Pulmonary hypertension (PH) was found in 78% of the reported cases. PCH typically showed characteristic diffuse or patchy ground-glass opacities (GGOs) and/or multiple ill-defined centrilobular nodules in the computed tomography.

Conclusions  The diagnosis of PCH requires a high clinical suspicion. However, both clinical presentations and radiographic studies often provide clues to the diagnosis, which may prompt early lung biopsy for a definite diagnosis.

     

Effect of pcDNA3.1- vascular endothelial growth factor 165 recombined vector on vascular buds in rabbit vertebral cartilage endplate

Background  This study aimed to investigate the effect of pcDNA3.1-vascular endothelial growth factor (VEGF)165 vector on vertebral cartilage endplate vascular buds and intervertebral discs.

Methods  Rabbits were randomly assigned to the control and experimental groups with 10 in each. In the experimental group, we anesthetized the rabbits and exposed the front vertebral body. Using the mark of the longitudinal ossature of the front vertebral body of the lumbar vertebrae, we advanced a needle at the central point of the front fourth and fifth lumbar intervertebral discs and injected 20 µl pcDNA3.1-VEGF165. Similarly, in the control group, we injected 20 µl pcDNA3.1. At 4 and 8 weeks post-injection, we examined the changes of the vertebral cartilage endplate using X-ray radiograph, histology, and scanning electron microscopy.

Results  The vertebral cartilage endplate calcification and degeneration in the experimental group were less than those in the control group at 8 weeks post-operation. The average number and diameter of vascular buds obviously increased in the experimental group at 4 and 8 weeks post-operation. The number of vascular buds and the diameter in the region of the inner annulus increased when compared to those in the area near the nucleus pulposus.

Conclusions  The pcDNA3.1-VEGF165 plasmid can increase the average number and diameter of vascular buds and decelerate intervertebral disc degeneration.

     

Evaluation and treatment of marginal grafts with surgical diseases in kidney transplantation

Background  Marginal renal grafts may alleviate the shortage of suitable organs to meet an increasing demand of kidney transplantation, especially when live donors are currently limited to relatives of patients in China. The aim of this study was to investigate how to increase the available donors pool, evaluation, and treatment of marginal donors.

Methods  We had performed 121 kidney transplantation cases with living relative donors. Five out of these cases applied marginal grafts with surgical diseases, including one renal stone, one duplex kidney, one renal leiomyoma and two cases of simple renal cysts. In each case, particular surgical interventions were exerted on the graft prior to standard engrafting procedures.

Results  All recipients recovered with functioning transplants given that their serum creatinine levels declined to a normal range within one week after operation. These recipients were subsequently followed up for 10 months on average and their kidney functions remained stable.

Conclusions  Marginal renal grafts with surgical diseases, which can be treated surgically before engrafting, may provide satisfying transplantation outcomes. Positive and cautious consideration of these grafts may increase renal donor pool.