In vitro and in vivo anticancer effects of mevalonate pathway modulation on human cancer cells

Background:

The increasing usage of statins (the 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) has revealed a number of unexpected beneficial effects, including a reduction in cancer risk.

Methods:

We investigated the direct anticancer effects of different statins approved for clinical use on human breast and brain cancer cells. We also explored the effects of statins on cancer cells using in silico simulations.

Results:

In vitro studies showed that cerivastatin, pitavastatin, and fluvastatin were the most potent anti-proliferative, autophagy inducing agents in human cancer cells including stem cell-like primary glioblastoma cell lines. Consistently, pitavastatin was more effective than fluvastatin in inhibiting U87 tumour growth in vivo. Intraperitoneal injection was much better than oral administration in delaying glioblastoma growth. Following statin treatment, tumour cells were rescued by adding mevalonate and geranylgeranyl pyrophosphate. Knockdown of geranylgeranyl pyrophosphate synthetase-1 also induced strong cell autophagy and cell death in vitro and reduced U87 tumour growth in vivo. These data demonstrate that statins main effect is via targeting the mevalonate synthesis pathway in tumour cells.

Conclusions:

Our study demonstrates the potent anticancer effects of statins. These safe and well-tolerated drugs need to be further investigated as cancer chemotherapeutics in comprehensive clinical studies.

The C-1021T polymorphism of dopamine β-hydroxylase is not associated with orthostatic hypotension in a Chinese population

To explore the association between the dopamine β-hydroxylase (DBH) gene C-1021T polymorphism and the occurrence of orthostatic hypotension (OH) in Chinese patients, the DBH C-1021T polymorphism was genotyped in 317 patients with OH and 664 age- and sex-matched controls with orthostatic normotension. All subjects underwent an upright posture study for the measurement of orthostatic blood pressure. OH was defined as a drop in blood pressure of 20/10 mm Hg or more within 3 min of assuming the upright posture. The allele frequency of the DBH C-1021T polymorphism in the orthostatic hypotensive group was similar to the orthostatic normotensive group (17.4 versus 14.9%, P>0.05). No statistical significant association was found between the distribution of the C-1021T genotypes and the risk of OH in both the orthostatic hypotensive and orthostatic normotensive groups even after adjustment for demographic parameters. Among the three different genotypes, blood pressure levels did not significantly differ in the general population in this study. The changes in orthostatic systolic or diastolic blood pressures among the different genotype groups were not detected (all P>0.05). The C-1021T polymorphism of the DBH was not associated with orthostatic hypotensive risk in a Chinese population.

Hepatitis C virus core antigen, an earlier and stronger predictor on sustained virological response in patients with genotype 1 HCV infection

Background

Earlier kinetics of serum HCV core antigen (HCVcAg) and its predictive value on sustained virological response (SVR) were investigated in patients with genotype 1 HCV infection during antiviral treatment.

Methods

In a multi-centered, randomized and positive drug-controlled phase IIb clinical trial on type Y peginterferon α-2b ( NCT01140997), forty-eight CHC patients who participated in pharmacokinetics were randomly divided into 4 cohorts and treated with PegIFNα (type Y peginterferon α-2b 90 μg, 135 μg, 180 μg and PegIFNα-2a 180 μg, respectively, once a week) and ribavirin (< 75 kg, 1000 mg daily and ≥ 75 kg, 1200 mg daily) for 48 weeks, and then followed up for 24 weeks. 32 patients infected with genotype 1 HCV and completed the whole process were included in this study. HCV RNAs were detected at baseline, and weeks 4, 12, 24, 48 and 72 using Cobas TaqMan. ARCHITECT HCVcAg was performed at 24, 48, 72, 96, 120 and 144 h in addition to the above time points. The receiver operating curves (ROCs) were performed to study the predictive values of HCVcAg decline on SVR.

Results

Following antiviral treatment, serum HCVcAg levels rapidly declined within the first week and correlated well with corresponding HCV RNA at baseline, weeks 4, 12, 24, 48 and 72 (r_s = 0.969, 0.928, 0.999, 0.983, 0.985 and 0.946, respectively, P < 0.001). All of the areas under the receiver operating curves (AUROCs) were more than 0.80 and showed good predictive power on SVR at 24, 48, 72, 96, 120 and 144 h. The144 h was the best predictive time point of HCVcAg decline on SVR because of its largest AUROC (more than 0.90).

Conclusions

Early kinetics of serum HCVcAg predicts SVR very well in genotype 1 CHC patients during antiviral treatment, and its reduction value at 144 h is an earlier and stronger predictor on SVR than rapid virological response and early virological response. (TRN: NCT01140997).

[Study on norovirus GII.4/Sydney 2012 variant in China]

OBJECTIVE

To study the nucleotide and amino acid sequences of norovirus G II.4/Sydney 2012 variants, in China.

METHODS

Twenty-two stool specimens, confirmed as G II.4/Sydney 2012- positive were collected from Beijing in the winter of 2012-2013. RT-PCR was performed to target the complete capsid gene. G II.4/Sydney 2012 strains from other regions in China were searched and obtained from the GenBank. Nucleotide and amino acid sequences of G II.4/Sydney 2012 strains were analyzed, using the CLUSTAL X(Version 1.83)and followed by phylogenetic analysis using Mega version 5.1.

RESULTS

The complete major capsid nucleotide sequences of thirty-eight G II.4/ Sydney 2012 strains from seven regions in China were obtained. The VP1 nucleotide and amino acid sequences diversity were 0.1%-3.3% and 0-3.1%, respectively. Result from phylogenetic analysis demonstrated that the G II.4/Sydney 2012 variant shared a common ancestor with both the dominant norovirus G II.4 variants Apeldoorn 2008 and the New Orleans 2009. G II.4/Sydney 2012 variants appeared to have had two A/D/E site combinations at the amino acid level, TSRN-GTT-SNT and TSRN-STT-SNT.

CONCLUSION

G II.4/Sydney 2012 variant had been circulating in many regions in China. There seemed a high nucleotide and amino acid identity among G II.4/Sydney 2012 strains collected from China. G II.4/Sydney 2012 variants showed different A/D/E site combination from other pandemic G II.4 variants.

Hypersensitive mAChRs are involved in the epiphora of transplanted glands

Autologous transplantation of the submandibular gland is an effective treatment for severe dry eye syndrome. However, more than 40% of patients experience epiphora 3 to 6 months after transplantation. The underlying mechanism of epiphora remains to be elucidated. To investigate the potential roles of muscarinic acetylcholine receptors (mAChRs) in the induction of epiphora in transplanted glands, we assessed and found elevated mRNA and protein expression of M1- and M3-mAChR in transplanted glands from epiphora patients. The content of inositol 1, 4, 5-trisphosphate was also elevated. Moreover, carbachol (5 and 10 µM) induced greater increase of [Ca(2+)]i in isolated epiphora submandibular cells than in controls. Although aquaporin-5 (AQP5) content and distribution in the apical and lateral plasma of epiphora glands did not change, AQP5 content was reduced in lipid microdomains (lipid rafts and caveolae) but increased in non-lipid microdomains compared with controls. Carbachol (10 µM) increased the ratio of non-lipid microdomain to total AQP5 in the cultured control submandibular gland tissue. Taken together, these results indicated that hypersensitive mAChRs might be involved in the epiphora of transplanted submandibular glands by modulating AQP5 trafficking.

Decreased submandibular adiponectin is involved in the progression of autoimmune sialoadenitis in non-obese diabetic mice

OBJECTIVE

To investigate a possible role of adiponectin in the pathogenesis of autoimmune sialoadenitis in non-obese diabetic (NOD) mouse model of Sjögren's syndrome.

MATERIALS AND METHODS

Expression of adiponectin and its receptors (AdipoR1/2) was detected by PCR, immunoblotting, or immunofluorescence. The level of adiponectin was quantified by ELISA. Adiponectin-related signaling molecules and pro-inflammatory cytokines were examined by PCR or immunoblotting. Apoptosis was evaluated by TUNEL staining, flow cytometry, and caspase 3 activation.

RESULTS

Adiponectin and AdipoR1/2 mRNA and protein were expressed in submandibular glands. Adiponectin immunostaining was widely diffused in the cytoplasm of acinar and ductal cells. AdipoR1 was mainly distributed in acinar cytoplasm, while AdipoR2 was predominantly located at acinar cell membrane. Submandibular adiponectin levels were reduced during the progression of autoimmune sialoadenitis in 7-, 14-, and 21-week-old NOD mice, while AdipoR1/2 levels were unchanged. The levels of phosphorylated adenosine monophosphate-activated protein kinase, extracellular signal-regulated kinase 1/2, and p38 mitogen-activated protein kinase were decreased, while interferon (IFN)-γ and glandular apoptosis were temporally increased at all time points. Moreover, exogenous adiponectin supplement inhibited, whereas neutralizing endogenous adiponectin by its antibody promoted IFN-γ-induced apoptosis and caspase 3 activation in cultured submandibular acinar cells.

CONCLUSIONS

Adiponectin plays a protective role on submandibular cells. Decreased adiponectin might promote glandular destruction in autoimmune sialoadenitis.

Clinical and epidemiologic characteristics of norovirus GII.4 Sydney during winter 2012-13 in Beijing, China following its global emergence

BACKGROUND

Limited information is available on the molecular epidemiology of GII.4 Sydney-associated diarrhea in China in the winter of 2012-13 during the global epidemic associated with the emergence of GII.4 Sydney.

METHODS

Fecal specimens collected from 171 diarrhea outpatients (one from each) between late October 2012 and the middle of March 2013 were examined for NoV by reverse transcription-polymerase chain reaction and sequences corresponding to both the NoV partial polymerase and partial capsid regions were analyzed phylogenetically. Clinical characteristics of GII.4 Sydney cases versus other NoV-positive cases detected in a previous study were compared statistically.

RESULTS

Twenty-six (15.2%, 26/171) outpatients with diarrhea were infected with NoV. Twenty-two of the 26 (84.6%) identified NoV strains clustered into GII.4 Sydney. There was a significant difference in symptoms of fever (χ(2), P<0.05 ), abdominal pain (χ(2), P<0.05 ) and diarrhea frequency (Mann-Whitney U test, P<0.05) between the GII.4 Sydney case group and other NoV-positive case group.

CONCLUSIONS

The new NoV variant, GII.4 Sydney, has been circulating in Beijing, China and became the predominant strain in the winter of 2012-13. GII.4 Sydney causes severe fever, abdominal pain and higher diarrhea frequency clinically compared to other NoV infections.

Regulation of circadian locomotor rhythm by neuropeptide Y-like system in Drosophila melanogaster

Circadian rhythms in behaviour and physiology exist widely in animals, plants, fungi and cyanobacteria. Although much work has been carried out to characterize the endogenous clock circuit, the output signals coupling the circadian pacemaker to behaviour and physiology remain elusive. Here, we show that neuropeptide F (NPF), a homologue of mammalian neuropeptide Y, and its G protein-coupled receptor NPFR1 regulate the locomotor rhythm in Drosophila melanogaster. Flies with loss of function in NPF or NPFR1 were unable to ramp up their activity before lights off under light : dark (LD) cycles, and oscillations in npf/NPF and npfr1/NPFR1 were found to correlate temporally with the locomotor rhythm. Furthermore, NPF is expressed in clock neurones including dorsolateral neurones (LNd s) and ventrolateral neurones (LNv s), whereas NPFR1 is expressed in dorsal neurone 1 (DN1) and LNd s. These results show that NPF signalling is involved in the circadian locomotor rhythm in LD cycles.

Transplantation of granulocytic myeloid-derived suppressor cells (G-MDSCs) could reduce colitis in experimental murine models

OBJECTIVE

Myeloid-derived suppressor cells (MDSCs) are a group of myeloid cells expressing CD11b and Gr-1 marker in mice and comprise at least two subsets: granulocytic MDSCs (G-MDSCs) and monocytic MDSCs (M-MDSCs). This study aimed to evaluate the therapeutic efficacy of transplantation of G-MDSC subsets from normal mice to colitis mice.

METHODS

Murine colitis model was induced by the intrarectal administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS). The mice were divided into four groups: control group, TNBS-induced colitis, TNBS-induced colitis plus normal saline injection and TNBS-induced colitis plus bone marrow-derived G-MDSCs injection (transplantation group). G-MDSCs were sorted and enriched via magnetic-activated cell sorting (MACS) program, the purity of the sorted cells was then identified using flow cytometry analysis. Sex cross-transplantation of dominant G-MDSCs was applied from normal mice to colitis models using i.v. injection. Changes of body weight, survival rate, myeloperoxidase (MPO) activity were monitored and macroscopic and microscopic injury scores are calculated. Donor cell Y chromosomes were assessed by in situ hybridization to assess reconstitutions.

RESULTS

After the transplantation of bone marrow-derived G-MDSCs from normal mice to colitis models, recipient mice showed increased survival rate, decreased macroscopic and microscopic injury scores and MPO activity, as well as lowered concentration of serum interleukin-6. Y chromosomes staining displayed colonization of donor cells of liver, spleen and colon tissues.

CONCLUSION

Bone marrow-derived G-MDSCs are effective in the improvement of murine colitis, but its effect in human needs further investigation.

Neuropsychiatric symptoms, seizure severity, employment, and quality of life of Jordanians with epilepsy

RATIONALE

Depression and anxiety are more strongly associated with quality of life (QOL) than seizure frequency in several populations with epilepsy. However, QOL is culturally determined and may be influenced by cultural values and norms as well as local policies and resources. The goal of this study is to investigate the impact of neuropsychiatric symptoms and seizure severity on QOL and employment in people with epilepsy living in Jordan.

METHODS

Seizure severity and complications, antiepileptic drug side effects, social stigma, neuropsychiatric symptoms, and mental health (MH-SF36) and physical health (PH-SF36) domains of QOL were assessed in 45 adult patients with epilepsy in a university neurology clinic. Multivariate regression analysis was used to evaluate the relationship between these variables and the quality of life of Jordanians with epilepsy.

RESULTS

Neuropsychiatric symptoms, seizure frequency, and history of injury due to seizure were associated with the MH-SF36. However, earlier age of seizure onset, longer duration of epilepsy, unemployment, and history of chronic disease was associated with lower PH-SF36 scores. Furthermore, there were no differences in QOL, neuropsychiatric symptoms, and seizure frequency in Jordanians who were employed versus unemployed in this study.

CONCLUSIONS

Neuropsychiatric symptoms were significantly associated with mental health-related QOL measures, but not with physically-related QOL measures, in Jordanians with epilepsy. For studies across populations, it is critical to separate mental health from physical health QOL measures. Furthermore, regional differences in culture and policy may more strongly influence employment status than individuals' experiences of epilepsy, neuropsychiatric symptoms, or QOL in some populations.

BST2/tetherin inhibits dengue virus release from human hepatoma cells

Type I interferons (IFN) have been shown to play an important role for inhibiting Dengue virus (DENV) infection. Identifying IFN-induced cellular proteins are essential for understanding its mechanisms against DENV. Here we established stable Huh7-derived cell lines expressing the IFN-induced cell membrane protein BST2 (Huh7-BST2) or its variant bearing a V5 tag at the C-terminal (Huh7-BST5CV5). These cell lines were infected with DENV to determine proteins modulating their anti-DENV response. We found that expression of BST2 did not affect the efficiency of DENV infection and intracellular replication. Rather, it significantly reduced the virion yield of the infected cells, particularly at low MOI infection. In addition, BST2 also decreased the foci formation and the size of infectious foci in cultured Huh7 monolayers with media containing methocellulose. The addition of the V5 tag at C-terminal inhibited the GPI modification of BST2 and blocked its shift from endoplasm to cytoplastic membrane. BST2CV5 did not affect DENV infection and foci formation in Huh7 cells but reduced virion yield by 1 log at low MOI infection. Interestingly, intracellular BST2CV5 expression was reduced by high level of DENV production.

DCs pulsed with novel HLA-A2-restricted CTL epitopes against hepatitis C virus induced a broadly reactive anti-HCV-specific T lymphocyte response

Objective

To determine the capacity of dendritic cells (DCs) loaded with single or multiple-peptide mixtures of novel hepatitis C virus (HCV) epitopes to stimulate HCV-specific cytotoxic T lymphocyte (CTL) effector functions.

Methods

A bioinformatics approach was used to predict HLA-A2-restricted HCV-specific CTL epitopes, and the predicted peptides identified from this screen were synthesized. Subsequent IFN-γ ELISPOT analysis detected the stimulating function of these peptides in peripheral blood mononuclear cells (PBMCs) from both chronic and self-limited HCV infected subjects (subjects exhibiting spontaneous HCV clearance). Mature DCs, derived in vitro from CD14⁺ monocytes harvested from the study subjects by incubation with appropriate cytokine cocktails, were loaded with novel peptide or epitope peptide mixtures and co-cultured with autologous T lymphocytes. Granzyme B (GrB) and IFN-γ ELISPOT analysis was used to test for epitope-specific CTL responses. T-cell-derived cytokines contained in the co-cultured supernatant were detected by flow cytometry.

Results

We identified 7 novel HLA-A2-restricted HCV-specific CTL epitopes that increased the frequency of IFN-γ-producing T cells compared to other epitopes, as assayed by measuring spot forming cells (SFCs). Two epitopes had the strongest stimulating capability in the self-limited subjects, one found in the E2 and one in the NS2 region of HCV; five epitopes had a strong stimulating capacity in both chronic and self-limited HCV infection, but were stronger in the self-limited subjects. They were distributed in E2, NS2, NS3, NS4, and NS5 regions of HCV, respectively. We also found that mDCs loaded with novel peptide mixtures could significantly increase GrB and IFN-γ SFCs as compared to single peptides, especially in chronic HCV infection subjects. Additionally, we found that DCs pulsed with multiple epitope peptide mixtures induced a Th1-biased immune response.

Conclusions

Seven novel and strongly stimulating HLA-A2-restricted HCV-specific CTL epitopes were identified. Furthermore, DCs loaded with multiple-epitope peptide mixtures induced epitope-specific CTLs responses.

Intestinal immune barrier integrity in rats with nonalcoholic hepatic steatosis and steatohepatitis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) has emerged as the major cause of chronic liver injury. Intestinal barrier plays an important role in the pathogenis of NAFLD. The aim of this article was to assess intestinal immune barrier function during the development of NAFLD.

METHODS

Totally 60 male Sprague-Dawley (SD) rats were divided into 2 groups: normal diet (ND) group and high-fat diet (HFD) group. NAFLD rat model was established in the HFD rat group. Portal blood endotoxin level was assessed by limulus test. The percentage of CD4+ cells and CD8+ cells in peripheral blood mononuclear cells (PBMC) and lymphocytes in Peyer's patches (PP) were analysed by flow cytometry. Intestinal secretory immunoglobulin A (SIgA) level was evaluated by enzyme-linked immunosorbent assay. Paired Student's t test was used for the statistic analysis.

RESULTS

HFD rats presented with simple steatosis at the 4th and 8th week and progressed to nonalcoholic steatohepatitis at the 12th week. Elevated lipopolysaccharides (LPS) level in HFD rats was observed at the 8th week ((1.54 ± 0.30) times of ND group, P < 0.01). CD4/CD8 ratios in PBMC and PP of HFD rats were increased at the 4th week ((1.50 ± 0.47) and (1.63 ± 0.34) times of ND group, P < 0.05) and decreased at the 8th week ((0.50 ± 0.16) and (0.61 ± 0.26) times of ND group, P < 0.05). At the 12th week, CD4/CD8 ratio ((1.47 ± 0.46) times, P < 0.05) in PP increased to levels observed in the 4th week. Intestinal SIgA expression of HFD rats was remarkably up-regulated at 12th week ((2.70 ± 1.65) times, P < 0.05).

CONCLUSION

Liver-gut axis in rats with NAFLD may mediate and improve intestinal immune function by increased CD4/CD8 ratio in PP and increased production of SIgA.

Long-term association between seizure outcome and depression after resective epilepsy surgery

OBJECTIVE

This study explored the association between long-term epilepsy surgery outcome and changes in depressive symptoms.

METHODS

Adults were enrolled between 1996 and 2001 in a multicenter prospective study to evaluate outcomes of resective epilepsy surgery. The extent of depressive symptoms and depression case status (none, mild, or moderate/severe) were assessed using the Beck Depression Inventory (BDI) preoperatively and 3, 12, 24, 48, and 60 months postoperatively. A mixed-model repeated-measures analysis was performed, adjusting for covariates of seizure location, gender, age, race, education, and seizure control.

RESULTS

Of the total 373 subjects, 256 were evaluated at baseline and 5 years after surgery. At baseline, 164 (64.1%) were not depressed, 34 (13.3%) were mildly depressed, and 58 (22.7%) had moderate to severe depression. After 5 years, 198 (77.3%) were not depressed, 20 (7.8%) were mildly depressed, and 38 (14.8%) were moderately to severely depressed. Five years after surgery, the reduction in mean change from baseline in BDI score was greater in subjects with excellent seizure control than in the fair and poor seizure control groups (p = 0.0006 and p = 0.02 respectively). Those with good seizure control had a greater reduction in BDI score than the poor seizure control group (p = 0.02) and borderline significant reduction compared with the fair seizure control group (p = 0.055).

CONCLUSION

Although study participants had initial improvement in depressive symptoms, on average, after resective surgery, only patients with good or excellent seizure control had sustained long-term improvement in mood.

Artificial recombinant cell-penetrating peptides interfere with envelopment of hepatitis B virus nucleocapsid and viral production

Hepatitis B virus (HBV) is a major human infectious pathogen, with over 300 million chronically infected patients worldwide. Current therapeutics for chronic HBV infection have shown only limited success. The plasma membrane represents an impermeable barrier for development of most macromolecular antiviral agents. To develop new anti-HBV macromolecules that can cross the membrane barrier, we designed a series of artificial recombinant peptides including cell penetrating sequence oligoarginine R7 and several nucleocapsid binding subunits (NBS). The anti-HBV function of these peptides was evaluated in a HBV DNA replicative cell line HepG2.2.15. Our results showed that the synthetic recombinant cell penetrating peptides retained the activity of cell penetrating in the living cells. HBV DNA in culture medium markedly decreased in cells treated with cell penetrating peptides bearing NBS for three days. Intracellular HBcAg and HBV DNA replicative intermediates increased by 2-3 fold. In conclusion, the synthetic recombinant cell penetrating peptides bearing NBS can efficiently enter into the cells; block nucleocapsid assembly and inhibit HBV release. Cell penetrating subunit presents a high efficiency tool to deliver synthetic antiviral peptides into cells.

Inhibitory effect of human interferon-beta-1a on activated rat and human hepatic stellate cells

BACKGROUND AND AIMS

Hepatic stellate cells (HSC) are the primary cell type mediating hepatic fibrosis. Although known for its antiviral effects, the inhibitory effects of interferon-beta (IFN-β) on HSC treatment have not yet been established.

METHODS

Both human and rat activated HSC cell lines were incubated with increasing concentrations of recombinant human IFN-β1a (rhIFN-β1a) for 24, 48 or 72 h. The effects of rhIFN-β1a on α-smooth muscle actin (α-SMA), collagen types I and III, transforming growth factor-β1 (TGF-β1), platelet-derived growth factor-BB (PDGF-BB), and mothers against decapentaplegic homolog (Smad4, Smad7) expression in HSC were examined using Western blotting and immunocytochemistry. Proliferation of HSC was evaluated via bromodeoxyuridine assay.

RESULTS

rhIFN-β1a treatment had a dose-dependent, inhibitory effect on α-SMA and collagen type I protein expression. In addition, rhIFN-β1a decreased the expression of collagen type III, TGF-β1, PDGF-BB and Smad4 protein expression in HSC compared with untreated cells. We also observed increased Smad7 protein expression and decreased proliferation in rhIFN-β1a-treated HSC.

CONCLUSIONS

Our data suggest that rhIFN-β1a treatment decreased α-SMA and collagen expression and inhibited the activation of HSC through the inhibition of the TGF-β and PDGF pathways.

Activation of transient receptor potential vanilloid subtype 1 increases secretion of the hypofunctional, transplanted submandibular gland

Hyposecretion occurs in most patients early after submandibular gland autotransplantation for severe keratoconjunctivitis sicca. Endogenous transient receptor potential vanilloid subtype 1 (TRPV1) has been recently demonstrated in rabbit submandibular glands, and activation of TRPV1 by capsaicin increases secretion in isolated glands, but the TRPV1-mediated secretory mechanism remains to be elucidated. The purpose of this study was to verify whether activation of TRPV1 by capsaicin could improve the secretion of transplanted gland and its underlying mechanism. The salivary flow of the transplanted glands was significantly decreased, and the mRNA and protein levels of TRPV1 and aquaporin 5 (AQP5) were downregulated in the transplanted glands. Topical capsaicin cream increased secretion and upregulated levels of TRPV1 and AQP5 in transplanted glands. Moreover, in cultured submandibular gland cells, capsaicin increased the mRNA expression of AQP5 and led to redistribution of AQP5 from the cytoplasm to the plasma membrane via TRPV1 activation. Capsaicin enhanced the phosphorylation of extracellular signal-regulated kinase (ERK). Preincubation of cells with PD98059, an inhibitor of ERK kinase, suppressed the capsaicin-induced mRNA expression of AQP5. In summary, the capsaicin-induced secretory mechanism involved activation of TRPV1 and upregulation of AQP5 in an ERK-dependent manner and promoted the redistribution of AQP5 in submandibular gland cells. Activation of TRPV1 may provide a new therapeutic strategy to improve submandibular gland hypofunction.

Transplanted endothelial progenitor cells ameliorate carbon tetrachloride-induced liver cirrhosis in rats

Cirrhosis is the most common end stage of liver diseases, and there are no effective treatment methods. Here we evaluated the effect of endothelial progenitor cell (EPC) transplantation from rat bone marrow (BM) on the development of cirrhosis induced by carbon tetrachloride (CCl(4)). Ex vivo generated, characterized, and cultivated rat BM-derived EPCs were identified by their vasculogenic properties in vitro. EPCs from male rats were transplanted into female rats via the intraportal vein 12 weeks after they had been challenged with CCl(4), and the rats were killed 16 weeks later. The control rats received only a saline infusion. The fibrosis index and donor cell engraftment were assessed after EPC transplantation. After transplantation via the portal vein, PKH26 labeling, polymerase chain reaction, and in situ hybridization analysis revealed that the donor EPCs had adhered to the vasolateral surfaces of blood vessels and established in the liver. EPCs reduced the expression of alpha-smooth muscle actin, collagen III, and transforming growth factor beta (P < 0.05) as well as levels of aspartate aminotransferase, alanine aminotransferase, and total bilirubin in the serum (P < 0.05), but at the same time they increased the levels of albumin and Ki67. CCl(4) treatment increased the international prothrombin ratio (P < 0.05) and reduced albumin levels, whereas EPCs restored these parameters to normal levels. These results suggest that EPC transplantation could play a role in regulating hepatocyte regeneration and ameliorating established liver cirrhosis.

Aspirin induces apoptosis in mesenchymal stem cells requiring Wnt/beta-catenin pathway

BACKGROUND AND OBJECTIVES

Mesenchymal stem cells (MSC) are multipotent progenitor cells that are have found use in regenerative medicine. We have previously observed that aspirin, a widely used anti-inflammatory drug, inhibits MSC proliferation. Here we have aimed to elucidate whether aspirin induces MSC apoptosis and whether this is modulated through the Wnt/beta-catenin pathway.

MATERIALS AND METHODS

Apoptosis of MSCs was assessed using Hoechst 33342 dye and an Annexin V-FITC/PI Apoptosis Kit. Expression of protein and protein phosphorylation were investigated using Western blot analysis. Caspase-3 activity was detected by applying a caspase-3/CPP32 Colorimetric Assay Kit.

RESULTS

In these MSCs, aspirin induced morphological changes characteristic of apoptosis, cytochrome c release from mitochondria, and caspase-3 activation. Stimulating the Wnt/beta-catenin pathway by both Wnt 3a and GSK-3beta inhibitors (LiCl and SB 216763), blocked aspirin-induced apoptosis and protected mitochondrial function, as demonstrated by decreased cytochrome c release and caspase-3 activity. Aspirin initially caused a time-dependent decrease in COX-2 expression but subsequently, and unexpectedly, elevated the latter. Stimulation of COX-2 expression by aspirin was further enhanced following stimulation of the Wnt/beta-catenin pathway. Application of the COX-2 inhibitor NS-398 suppressed elevated COX-2 expression and promoted aspirin-induced apoptosis.

CONCLUSION

These results demonstrate that the Wnt/beta-catenin pathway is a key modulator of aspirin-induced apoptosis in MSCs by regulation of mitochrondrial/caspase-3 function. More importantly, our findings suggest that aspirin may influence MSC survival under certain conditions; therefore, it should be used with caution when considering regenerative MSC transplantation in patients with concomitant chronic inflammatory diseases such as arthritis.

SARS-CoV Nucleocapsid Protein Induced Apoptosis of COS-1 Mediated by the Mitochondrial Pathway

To investigate the apoptosis effect of SARS coronavirus nucleocapsid protein on cultured cell lines and to explore the possible pathway of apoptosis. pCDNA3.1(-)/his-myc vector containing the SARS coronavirus nucleocapsid gene (N), matric gene (M), spike gene (S) were transfected into COS-1, Huh-7 and HepG2 cells. Apoptosis induced by SARS coronavirus N protein under starvation of serum of COS-1 cells was monitored by Annexin V and electron microscopy assays. Intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (DeltaPsim) were determined by flow cytometric assay. Cytochrome C, cleaved caspase (cysteine aspartic acid protease)-3, 9, and poly (ADP-ribose) polymerase (PARP) were detected by Western blot. After removal of serum in COS-1 cells, we observed the loss of DeltaPsim, the increase of ROS and cytochrome C release into cytosol and subsequent activation of caspase-3 and PARP cleavage. The pan-caspase inhibitor z-VAD-fmk can block the activation of caspase 3, 9 and PARP cleavage. In conclusion, SARS coronavirus N protein can induce apoptosis of COS-1 cells by activating mitochondrial pathway. SARS coronavirus M, S protein can not induce apoptosis in COS-1, HepG2 and Huh-7 and SARS coronavirus N protein can not induce apoptosis in HepG2 and Huh-7 by methods used in this study.

Isoproterenol improves secretion of transplanted submandibular glands

Autotransplantation of the submandibular gland is effective for severe keratoconjunctivitis sicca. However, most transplants show decreased secretion shortly after the operation, which leads to obstruction of Wharton's duct. The hypothesis that decreased catecholamine release due to denervation contributes to hypofunction in the early phase was tested in transplanted glands in rabbits. We found that salivary flow, expression of beta(1)- and beta(2)-adrenoceptor, and the maximum binding capacity were markedly decreased in the transplanted glands. Isoproterenol significantly reversed the decreased secretion, enhanced the expressions of beta(1)- and beta(2)-adrenoceptor, and ameliorated the atrophy of acinar cells. The contents of cAMP and phospho-ERK 1/2 were increased after isoproterenol treatment. These results indicate that lack of beta-adrenoceptor stimulation is involved in early dysfunction of the transplanted gland. Isoproterenol treatment moderates structural injury and improves secretory function in the transplanted submandibular gland through up-regulating beta(1)- and beta(2)-adrenoceptor expression and post-receptor signal transduction.

Evaluation of INNO-LiPA in detection of HBV drug resistance mutation

AIM: To assess the accuracy of INNO-LiPA HBV DR v2 for detecting hepatitis B virus (HBV) drug resistance.

METHODS: Sera from 237 chronic hepatitis B patients undergoing lamivudine or adefovir treatment were detected using INNO-LiPA and direct sequencing of the reverse transcriptase region of the HBV Polymerase gene.

RESULTS: Sequencing results were observed for 179/235 samples (76.1%) and 1293/1410 amino acid positions (91.7%). It showed high concordance with directing antiviral drug-resistance mutations, particularly for the sensitive detection of mixed drug-resistance mutations.

CONCLUSION: The INNO-LiPA HBV DR v2 appears to be useful for the rapid antiviral drug-resistance mutations assay of HBV.