Multiple sclerosis (MS) is an immune-mediated disorder in the central nervous system (CNS) characterized by inflammation and demyelination as well as axonal and neuronal degeneration. So far effective therapies to reverse the disease are still lacking; most therapeutic drugs can only ameliorate the symptoms or reduce the frequency of relapse. Dendritic cells (DCs) are professional antigen presenting cells (APCs) that are key players in both mediating immune responses and inducing immune tolerance. Increasing evidence indicates that DCs contribute to the pathogenesis of MS and might provide an avenue for therapeutic intervention. Here, we summarize the immunogenic and tolerogenic roles of DCs in MS and review medicinal drugs that may affect functions of DCs and have been applied in clinic for MS treatment. We also describe potential therapeutic molecules that can target DCs by inducing anti-inflammatory cytokines and inhibiting proinflammatory cytokines in MS.
Glycyrrhetinic acid (GA) is a natural compound extracted from liquorice, which is often used in traditional Chinese medicine. The purpose of the present study was to investigate the antitumor effect of GA in human non-small cell lung cancer (NSCLC), and its underlying mechanisms in vitro. We have shown that GA suppressed the proliferation of A549 and NCI-H460 cells. Flow cytometric analysis showed that GA arrested cell cycle in G0/G1 phase without inducing apoptosis. Western blot analysis indicated that GA mediated G1-phase cell cycle arrest by upregulation of cyclin-dependent kinase inhibitors (CKIs) (p18, p16, p27 and p21) and inhibition of cyclins (cyclin-D1, -D3 and -E) and cyclin-dependent kinases (CDKs) (CDK4, 6 and 2). GA also maintained pRb phosphorylation status, and inhibited E2F transcription factor 1 (E2F-1) in both cell lines. GA upregulated the unfolded proteins, Bip, PERK and ERP72. Accumulation of unfolded proteins in the endoplasmic reticulum (ER) triggered the unfolded protein response (UPR), which could be the mechanism by which GA inhibited cell proliferation in NSCLC cells. GA then coordinated the induction of ER chaperones, which decreased protein synthesis and induced cell cycle arrest in the G1 phase. This study provides experimental evidence to support the development of GA as a chemotherapeutic agent for NSCLC.
glycyrrhetinic acid; cell cycle arrest; ER stress; NSCLC
The emerging H5 clade 126.96.36.199 viruses of different NA subtypes have been detected in different domestic poultry in China. We evaluated the receptor binding property and transmissibility of four novel H5 clade 188.8.131.52 subtype highly pathogenic avian influenza viruses. The results show that these viruses bound to both avian-type (α-2,3) and human-type (α-2,6) receptors. Furthermore, we found that one of these viruses, GS/EC/1112/11, not only replicated but also transmitted efficiently in guinea pigs. Therefore, such novel H5 subtype viruses have the potential of a pandemic threat.
Oxidative stress plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD) and in the induction of corticosteroid (CS) insensitivity. Chronic ozone exposure leads to a model of COPD with lung inflammation and emphysema. Mitogen-activated protein kinase phosphatase-1 (MKP-1) may underlie CS insensitivity in COPD. We determined the role played by MKP-1 by studying the effect of corticosteroids in wild-type C57/BL6J and MKP-1−/− mice after chronic ozone exposure. Mice were exposed to ozone (3 ppm, 3 h) 12 times over 6 weeks. Dexamethasone (0.1 or 2 mg/kg; intraperitoneally) was administered before each exposure. Mice were studied 24 h after final exposure. In ozone-exposed C57/BL6J mice, bronchial hyperresponsiveness (BHR) was not inhibited by both doses of dexamethasone, but in MKP-1−/− mice, there was a small inhibition by high dose dexamethasone (2 mg/kg). There was an increase in mean linear intercept after chronic ozone exposure in both strains which was CS-insensitive. There was lesser inflammation after low dose of dexamethasone in MKP-1−/− mice compared to C57/Bl6J mice. Epithelial and collagen areas were modulated in ozone-exposed MKP-1−/− mice treated with dexamethasone compared to C57/Bl6J mice. MKP-1 regulated the expression of MMP-12, IL-13 and KC induced by ozone but did not alter dexamethasone׳s effects. Bronchial hyperresponsiveness, lung inflammation and emphySEMa after chronic exposure are CS-insensitive, and the contribution of MKP-1 to CS sensitivity in this model was negligible.
Ozone exposure; Emphysema; Lung inflammation; Bronchial hyperresponsiveness; Mitogen-activated protein kinase phosphatase 1 (MKP-1)
The strains of Newcastle disease virus (NDV) can be divided into two distinct clades: class I and class II. At present, limited molecular epidemiological data are available for the class I virus at live bird markets (LBMs). Knowing the genomic and antigenic characteristics of class I NDVs might provide important insights into the evolution dynamics of these viruses. In this study class I NDVs isolated from LBMs in Eastern China between 2008 and 2012 were characterized.
We characterized 34 class I NDVs genetically and 15 of the 34 NDVs pathologically which originated from geese, chickens and ducks at live bird markets. Based on the older classification system, twelve of fourteen strains isolated from 2008 to 2010 belonged to sub-genotype 3b. However, the rest 22 strains formed a separate novel cluster in genotype 3, which was designated as sub-genotype 3c. When based on the new classification system, sub-genotype 3b was classified into sub-genotype 1a and the sub-genotype 3c was classified into sub-genotype 1b. Over 62% (21/34) of the viruses were chicken-origin and only 13 isolates were waterfowl-origin. The Cross-neutralization reactions between CK/JS/05/11, CK/JS/06/12 and the vaccine strain LaSota showed significant antigenic differences between them.
Currently, sub-genotype 3c (or 1b) NDVs are the most frequently isolated classI strains at LBMs in Eastern China., and the class I NDVs has transferred from waterfowls to chickens and circulated in chicken flocks extensively.
Class I Newcastle disease virus; Sub-genotype 3c; Sub-genotype 1b; Genetic; Antigenticy
Sinomenine is a principal ingredient of traditional Chinese medicine, Sinomenium Acutum, which has been reported to have various pharmacological effects including anti-rheumatism and immunomodulation. This study examined the effects of sinomenine in rats that received chronic constriction injury (CCI), a model of peripheral neuropathic pain. CCI injury on the right sciatic nerve led to long-lasting mechanical hyperalgesia. Acute sinomenine treatment (10–40 mg/kg, i.p.) significantly and dose-dependently reversed mechanical hyperalgesia. In addition, the antinociceptive effects of sinomenine remained stable during repeated daily treatment for up to 2 weeks. Although sinomenine did not alter the duration of immobility in the forced swimming test in healthy animals, it dose-dependently reversed the increased immobility time in rats receiving CCI, suggesting that sinomenine attenuated chronic pain-induced depressive-like behavior. The antinociceptive effects of sinomenine were blocked by the GABAa receptor antagonist bicuculine. The doses of sinomenine studied here did not significantly alter the spontaneous locomotor activity. Together, these results suggested that sinomenine exerts significant antinociceptive effects for neuropathic pain via GABAa-mediated mechanism, which suggests that sinomenine may be useful for the management of chronic painful conditions such as neuropathic pain.
Benzene is an occupational toxicant and an environmental pollutant that is able to induce the production of reactive oxygen species (ROS), causing oxidative stress and damages of the macromolecules in target cells, such as the hematopoietic stem cells. We had previously found that embryonic yolk sac hematopoietic stem cells (YS-HSCs) are more sensitive to benzene toxicity than the adult bone marrow hematopoietic stem cells, and that nuclear factor-erythroid-2-related factor 2 (Nrf2) is the major regulator of cytoprotective responses to oxidative stress. In the present report, we investigated the effect of PKM2 and Nrf2-ARE pathway on the cellular antioxidant response to oxidative stress induced by benzene metabolite benzoquinone (BQ) in YS-HSC isolated from embryonic yolk sac and enriched by magnetic-activated cell sorting (MACS). Treatment of the YS-HSC with various concentrations of BQ for 6 hours induces ROS generation in a dose-dependent manner. Additional tests showed that BQ is also capable of inducing expression of NADPH oxidase1 (NOX1), and several other antioxidant enzymes or drug-metabolizing enzymes, including heme oxygenase 1 (HMOX1), superoxide dismutase (SOD), catalase and NAD(P)H dehydrogenase quinone 1 (NQO1). Concomitantly, only the expression of PKM2 protein was decreased by the treatment of BQ but not the PKM2 mRNA, which suggested that BQ may induce PKM2 degradation. Pretreatment of the cells with antioxidant N-acetylcysteine (NAC) decreased ROS generation and prevented BQ-induced PKM2 degradation, suggesting involvement of ROS in the PKM2 protein degradation in cellular response to BQ. These findings suggest that BQ is a potent inducer of ROS generation and the subsequent antioxidant responses of the YS-HSC. The accumulated ROS may attenuate the expression of PKM2, a key regulator of the pyruvate metabolism and glycolysis.
AIM: To discuss strategies and prognosis for the emergency treatment of ruptured bleeding in primary hepatocellular carcinoma.
METHODS: The retrospective analysis was performed by examining the emergency treatment experiences of 60 cases of ruptured bleeding in primary hepatocellular carcinoma. The treatment methods included surgical tumour resection, transcatheter arterial embolization (TAE) and non-surgical treatment. Univariate and multivariate analyses were performed to identify the risk factors that impacted 30-d mortality in the research groups.
RESULTS: The 30-d mortality of all patients was 28.3% (n = 17). The univariate analysis showed that Child-Pugh C level liver function, shock, massive blood transfusion and large tumour volume were risk factors that influenced 30-d mortality. The multivariate analysis showed that shock and massive blood transfusion were independent risk factors that impacted the 30-d mortality of surgical resection. As for the TAE patients, larger tumour volume was a risk factor towards prognosis.
CONCLUSION: Radical resection and TAE therapy would achieve better results in carefully selected ruptured hepatocellular tumours.
Hepatocellular carcinoma; Spontaneous rupture; Liver resection
The prevalence of childhood leukemia is increasing rapidly all over the world. However, studies on maternal benzene exposure during pregnancy and childhood acute lymphoblastic leukemia (ALL) have not been systematically assessed. Therefore, we performed a meta-analysis to investigate the association between maternal solvent, paint, petroleum exposure, and smoking during pregnancy and risk of childhood ALL.
Relevant studies up to September 1st, 2013 were identified by searching the PubMed, EMBASE, Cochrane library and the Web of Science databases. The effects were pooled using either fixed or random effect models based on the heterogeneity of the studies.
Twenty-eight case-control studies and one cohort study were included for analysis, with a total of 16,695 cases and 1,472,786 controls involved. Pooled odds ratio (OR) with 95% confidence interval (CI) for ALL was 1.25 (1.09, 1.45) for solvent, 1.23 (1.02, 1.47) for paint, 1.42 (1.10, 1.84) for petroleum exposure, and 0.99 (0.93, 1.06) for maternal smoking during pregnancy. No publication bias was found in this meta-analysis and consistent results were observed for subgroup and sensitivity analyses.
Childhood ALL was associated with maternal solvent, paint, and petroleum exposure during pregnancy. No association was found between ALL and maternal smoking during pregnancy. Avoidance of maternal occupational and environmental benzene exposure during pregnancy could contribute to a decrease in the risk of childhood ALL.
Graphene is composed of a single atomic layer of carbon which has excellent mechanical, electrical and optical properties. It has the potential to be widely used in the fields of physics, chemistry, information, energy and device manufacturing. In this paper, we briefly review the concept, structure, properties, preparation methods of graphene and its application in lithium ion batteries. A continuous 3D conductive network formed by graphene can effectively improve the electron and ion transportation of the electrode materials, so the addition of graphene can greatly enhance lithium ion battery’s properties and provide better chemical stability, higher electrical conductivity and higher capacity. In this review, some recent advances in the graphene-containing materials used in lithium ion batteries are summarized and future prospects are highlighted.
Graphene; Lithium ion battery; Electrode materials; Electrochemical characterizations
Tubal pregnancy with caesarean scar pregnancy is rare. Early, accurate diagnosis and treatment for this kind of ectopic pregnancy can lead to a decrease of maternal morbidity and mortality. Here, we report a rare case of spontaneous tubal pregnancy co-existing with caesarean scar pregnancy. After timely emergency laparoscopy and curettage, the patient was cured.
Ectopic pregnancy; fallopian pregnancy; caesarean scar pregnancy; laparoscopy; curettage
Objective: To investigate different protective effects of recombinant H. pylori multi-epitope antigen (rIB) with cholera toxin subunit B (rCTB) as the intramolecular/extramolecular adjuvant though different immunization routes in a Helicobacter pylori infected mouse model. Methods: By using rCTB as the intramolecular/extramolecular adjuvant of rIB, BALB/c mice were immunized through oral administration or intramuscular injection, on day 0, 14, 28. Every 14 days, ELISA was used to detect serum specific IgG and IgA titers after immunization. After the last immunization, H. pylori SS1 challenge was performed, and urease test, Gram staining after smearing of mouse gastric tissue, PCR, pathology and immunohistochemistry were used to evaluate preventive effect of the recombinant protein vaccine. Results: After immunization three times, intramolecular injection could induce high titers of serum specific IgG antibody, and the antibody titer in rIB group, rCTB+rIB and rBIB group was 2000, 5000 and 7500, respectively (P < 0.05). Specific IgA antibody was only detected in rBIB oral administration group. The immune protection rate in rBIB oral administration group was significantly higher than that in rBIB intramolecular injection group (33.3% vs. 83%), indicating significant difference. Conclusion: rCTB has good intramolecular/extramolecular immune adjuvant effects, and its intramolecular immune adjuvant effect is better. Both intramolecular injection and oral administration of rBIB have immune protective effect against H. pylori challenge, and oral administration of rBIB exerts better immune protective effect.
Helicobacter pylori; recombinant vaccine; cholera toxin subunit B; adjuvant; immunological response
Objective: To study immunization procedures and preparation methods of specific IgY antibodies (IgY-Hp, IgY-IB) produced by hens immunized with Helicobacter pylori (Hp) bacterial antigen and recombinant Hp specific antigen IB, detect the inhibition effects on Hp growth and Hp urease activity, and study the effects of oral administration for treating Hp infection. Methods: By using recombinant cholera toxin subunit B (rCTB) as an adjuvant, hens received intramuscular injection immunization for continuous 7 times at an interval of 14 days. Then, the eggs were collected; IgY was purified. Results: On day 49 after hens were immunized, levels of two antibodies all reached 1:12800; after they were purified by Ammonium sulfate precipitation, their purity was over 80%. IgY-Hp could inhibit Hp growth and inhibit Hp urease activity; although in vitro, IgY-IB could not inhibit Hp growth but could inhibit Hp urease activity. The experiments in vivo found that when IgY-Hp or IgY-IB with sucralfate dual oral therapy was used to treat Hp infected mouse model, the cure rate all could reach 83.3%. Conclusion: According to immunization procedure, high titer specific IgY antibody (1:12800) can be obtained in 49 days and its titer remains stable. Oral administration of the specific IgY antibodies in Hp infected mice can reach a cure rate of 83.3%, and the antibodies are expected to become new drugs and therapeutic methods of targeted therapy against Hp infection.
Helicobacter pylori; specific IgY; antibacterial effect
Magnetite exhibits unique electronic, magnetic, and structural properties in extreme conditions that are of great research interest. Previous studies have suggested a number of transitional models, although the nature of magnetite at high pressure remains elusive. We have studied a highly stoichiometric magnetite using inelastic X-ray scattering, X-ray diffraction and emission, and Raman spectroscopies in diamond anvil cells up to ~20 GPa, while complementary electrical conductivity measurements were conducted in a cubic anvil cell up to 8.5 GPa. We have observed an elastic softening in the diagonal elastic constants (C11 and C44) and a hardening in the off-diagonal constant (C12) at ~8 GPa where significant elastic anisotropies in longitudinal and transverse acoustic waves occur, especially along the  direction. An additional vibrational Raman band between the A1g and T2g modes was also detected at the transition pressure. These abnormal elastic and vibrational behaviors of magnetite are attributed to the occurrence of the octahedrally-coordinated Fe2+-Fe3+-Fe2+ ions charge-ordering along the  direction in the inverse spinel structure. We propose a new phase diagram of magnetite in which the temperature for the metal-insulator and distorted structural transitions decreases with increasing pressure while the charge-ordering transition occurs at ~8 GPa and room temperature.
We investigate the impact of the residual kidney volume measured by tumor volumetry on preoperative imaging in predicting post-operative renal function. Nephron sparing surgery (NSS) in renal cell carcinoma (RCC) is the standard treatment for T1 kidney tumors. Resection of kidney tumors in solidary kidneys needs precise preoperative counseling of patients regarding post-operative renal function.
Patients planned for renal tumor surgery who underwent prior nephrectomy on the contralateral side were included. We identified 35 patients in our database that underwent NSS in solitary kidneys and met the inclusion criteria. Tumor volumetry was performed on computer tomography (CT) or magnetic resonance imaging (MRI) with the Medical Imaging Interaction Toolkit (MITK). Clinical and pathological data were assessed. Follow-up data included renal function over 3 years.
Mean age was 64 ± 8.1 years. Mean tumor volume on imaging was 27.5 ± 48.6 cc. Mean kidney volume was 195.2 ± 62.8 cc and mean residual kidney volume was 173.4 ± 65.3 cc. We found a correlation between renal function (MDRD) and residual kidney volume on imaging 1-week post-surgery (p = 0.038). Mid- and long-term renal function was not associated with residual kidney volume.
In conclusion, renal volumetry may predict early renal function after NSS.
Nephron sparing surgery; Renal cell cancer; Renal function; Solitary kidney; Tumor volume
Ganglioside as a neurotrophic drug has been hitherto widely used in China, although Guillain-Barré syndrome (GBS) following intravenous ganglioside treatment was reported in Europe several decades ago. We identified 7 patients who developed GBS after intravenous use of gangliosides (ganglioside+ group) and compared their clinical data with those of 77 non-ganglioside-associated GBS patients (ganglioside− group) in 2013, aiming at gaining the distinct features of ganglioside-associated GBS. Although the mean age, protein levels in cerebrospinal fluid (CSF) and frequency of cranial nerve involvement were similar between the two groups, the Hughes Functional Grading Scale (HFGS) score and the Medical Research Council (MRC) sum score at nadir significantly differed (4.9±0.4 vs 3.6±1.0; 7.7±5.5 vs 36.9±14.5, both p<0.001), indicating a higher disease severity of ganglioside-associated GBS. A higher ratio of patients with ganglioside-associated GBS required mechanical ventilation (85.7% vs 15.6%, p<0.01). The short-term prognosis of ganglioside-associated GBS, as measured by the HFGS score and the MRC sum score at discharge, was poorer (4.3±0.5 vs 2.8±1.1; 17.3±12.9 vs 46.0±13.9, both p<0.001). All the patients in the ganglioside+ group presented an axonal form of GBS, namely acute motor axonal neuropathy (AMAN). When compared with the AMAN patients in the ganglioside− group, more severe functional deficits at nadir and poorer recovery after standard treatment were still prominent in ganglioside-associated GBS. Anti-GM1 and anti-GT1a antibodies were detectable in patients with AMAN while not in patients with the demyelinating subtype of GBS. The concentrations of these antibodies in patients with AMAN were insignificantly different between the ganglioside+ and ganglioside− groups. In sum, ganglioside-associated GBS may be a devastating side effect of intravenous use of gangliosides, which usually manifests a more severe clinical course and poorer outcome.
Oxidative stress is a well-established event in the pathology of several neurobiological diseases. Sirt3 is a nicotinamide adenine nucleotide (NAD+)-dependent protein deacetylase that regulates mitochondrial function and metabolism in response to caloric restriction and stress. This study aims to investigate the role of Sirt3 in H2O2 induced oxidative neuronal injury in primary cultured rat cortical neurons. We found that H2O2 treatment significantly increased the expression of Sirt3 in a time-dependent manner at both mRNA and protein levels. Knockdown of Sirt3 with a specific small interfering RNA (siRNA) exacerbated H2O2-induced neuronal injury, whereas overexpression of Sirt3 by lentivirus transfection inhibited H2O2-induced neuronal damage reduced the generation of reactive oxygen species (ROS), and increased the activities of endogenous antioxidant enzymes. In addition, the intra-mitochondrial Ca2+ overload, but not cytosolic Ca2+ increase after H2O2 treatment, was strongly attenuated after Sirt3 overexpression. Overexpression of Sirt3 also increased the content of mitochondrial DNA (mtDNA) and the expression of mitochondrial biogenesis related transcription factors. All these results suggest that Sirt3 acts as a prosurvival factor playing an essential role to protect cortical neurons under H2O2 induced oxidative stress, possibly through regulating mitochondrial Ca2+ homeostasis and mitochondrial biogenesis.
Sirt3; oxidative stress; mitochondria; Ca2+; mitochondrial biogenesis
Small molecule probes have been employed extensively to explore biological systems and elucidate cellular signaling pathways. In this study, we utilize an inhibitor of bacterial communication to monitor changes in the proteome of Salmonella enterica serovar Typhimurium with the aim of discovering new processes regulated by AI-2-based quorum sensing (QS), a mechanism of bacterial intracellular communication that allows for the coordination of gene expression in a cell density-dependent manner. In S. typhimurium, this system regulates the uptake and catabolism of intracellular signals and has been implicated in pathogenesis, including the invasion of host epithelial cells. We demonstrate that our QS antagonist is capable of selectively inhibiting the expression of known QS-regulated proteins in S. typhimurium, thus attesting that QS inhibitors may be used to confirm proposed and elucidate previously unidentified QS pathways without relying on genetic manipulation.
Thousands of long noncoding RNAs (lncRNAs) have been reported in mammalian genomes. These RNAs represent an important subset of pervasive genes involved in a broad range of biological functions. Aberrant expression of lncRNAs is associated with many types of cancers. Here, in order to explore the potential lncRNAs involved in hepatocellular carcinoma (HCC) oncogenesis, we performed lncRNA gene expression profile analysis in 3 pairs of human HCC and adjacent non-tumor (NT) tissues by microarray.
Differentially expressed lncRNAs and mRNAs were detected by human lncRNA microarray containing 33,045 lncRNAs and 30,215 coding transcripts. Bioinformatic analyses (gene ontology, pathway and network analysis) were applied for further study of these differentially expressed mRNAs. By qRT-PCR analysis in nineteen pairs of HCC and adjacent normal tissues, we found that eight lncRNAs were aberrantly expressed in HCC compared with adjacent NT tissues, which is consistent with microarray data.
We identified 214 lncRNAs and 338 mRNAs abnormally expressed in all three HCC tissues (Fold Change ≥2.0, P<0.05 and FDR <0.05) with the genome-wide lncRNAs and mRNAs expression profile analysis. The lncRNA-mRNA co-expression network was constructed, which may be used for predicting target genes of lncRNAs. Furthermore, we demonstrated for the first time that BC017743, ENST00000395084, NR_026591, NR_015378 and NR_024284 were up-regulated, whereas NR_027151, AK056988 and uc003yqb.1 were down-regulated in nineteen pairs of HCC samples compared with adjacent NT samples. Expression of seven lncRNAs was significantly correlated to their nearby coding genes. In conclusion, our results indicated that the lncRNA expression profile in HCC was significantly changed, and we identified a series of new hepatocarcinoma associated lncRNAs. These results provide important insights about the lncRNAs in HCC pathogenesis.
In the present study we explored the role of β-catenin in mediating chick retina regeneration. The chick can regenerate its retina by activating stem/progenitor cells present in the ciliary margin (CM) of the eye or via transdifferentiation of the retinal pigmented epithelium (RPE). Both modes require fibroblast growth factor 2 (FGF2). We observed, by immunohistochemistry, dynamic changes of nuclear β-catenin in the CM and RPE after injury (retinectomy). β-catenin nuclear accumulation was transiently lost in cells of the CM in response to injury alone, while the loss of nuclear β-catenin was maintained as long as FGF2 was present. However, nuclear β-catenin positive cells remained in the RPE in response to injury and were BrdU-/p27+, suggesting that nuclear β-catenin prevents those cells from entering the cell cycle. If FGF2 is present, the RPE undergoes dedifferentiation and proliferation concomitant with loss of nuclear β-catenin. Moreover, retinectomy followed by disruption of active β-catenin by using a signaling inhibitor (XAV939) or over-expressing a dominant negative form of Lef-1 induces regeneration from both the CM and RPE in the absence of FGF2. Our results imply that β-catenin protects cells of the CM and RPE from entering the cell cycle in the developing eye, and specifically for the RPE during injury. Thus inactivation of β-catenin is a pre-requisite for chick retina regeneration.
Choline plays a lipotropic role in lipid metabolism as an essential nutrient. In this study, we investigated the effects of choline (5, 35 and 70 μM) on DNA methylation modifications, mRNA expression of the critical genes and their enzyme activities involved in hepatic lipid metabolism, mitochondrial membrane potential (Δψm) and glutathione peroxidase (GSH-Px) in C3A cells exposed to excessive energy substrates (lactate, 10 mM; octanoate, 2 mM and pyruvate, 1 mM; lactate, octanoate and pyruvate-supplemented medium (LOP)). Thirty five micromole or 70 μM choline alone, instead of a low dose (5 μM), reduced hepatocellular triglyceride (TG) accumulation, protected Δψm from decrement and increased GSH-Px activity in C3A cells. The increment of TG accumulation, reactive oxygen species (ROS) production and Δψm disruption were observed under LOP treatment in C3A cells after 72 h of culture, which were counteracted by concomitant treatment of choline (35 μM or 70 μM) partially via reversing the methylation status of the peroxisomal proliferator-activated receptor alpha (PPARα) gene promoter, upregulating PPARα, carnitine palmitoyl transferase-I (CPT-I) and downregulating fatty acid synthase (FAS) gene expression, as well as decreasing FAS activity and increasing CPT-I and GSH-Px activities. These findings provided a novel insight into the lipotropic role of choline as a vital methyl-donor in the intervention of chronic metabolic diseases.
choline; hepatic lipid metabolism; mitochondria; proliferator-activated receptor alpha; methylation
In enteric bacteria, the kinase LsrK catalyzes the phosphorylation of the C5-hydroxyl group in the linear form of 4,5-dihydroxy-2,3-pentanedione (DPD), the precursor of the type II bacterial quorum sensing molecule (AI-2). This phosphorylation is required for AI-2 sequestration in the cytoplasm and subsequent derepression of AI-2 related genes necessary for quorum development. While LsrK is a critical enzyme within the DPD quorum sensing relay system, kinetic details of this kinase have yet to be reported. A continuous UV-vis spectrophotometric assay was developed, which allowed steady-state kinetic analysis of LsrK to be undertaken with the substrates ATP and DPD. The data was most consistent with a rapid equilibrium ordered mechanism with ATP binding first: kcat (7.4 ± 0.6 s−1), Km,ATP (150 ± 30 µM) and Km(app),DPD (1.0 ± 0.2 mM). The assay also allowed a DPD substrate profile to be conducted, which provided an unexpected biochemical disconnect between the previous agonist/antagonist cell based reporter assay and the LsrK assay presented herein. Together these findings raise the importance of LsrK and lay the foundation not only for further understanding of this enzyme and its critical biological role but also the rational design of regulatory molecules targeting AI-2 quorum sensing in pathogenic bacteria.
A bunch of microRNAs (miRNAs) have been demonstrated to be aberrantly expressed in cancer tumor tissue and serum. The miRNA signatures identified from the serum samples could serve as potential noninvasive diagnostic markers for breast cancer. The role of the miRNAs in cancerigenesis is unclear. In this study, we generated the expression profiles of miRNAs from the paired breast cancer tumors, normal, tissue, and serum samples from eight patients using small RNA-sequencing. Serum samples from eight healthy individuals were used as normal controls. We identified total 174 significantly differentially expressed miRNAs between tumors and the normal tissues, and 109 miRNAs between serum from patients and serum from healthy individuals. There are only 10 common miRNAs. This suggests that only a small portion of tumor miRNAs are released into serum selectively. Interestingly, the expression change pattern of 28 miRNAs is opposite between breast cancer tumors and serum. Functional analysis shows that the differentially expressed miRNAs and their target genes form a complex interaction network affecting many biological processes and involving in many types of cancer such as prostate cancer, basal cell carcinoma, acute myeloid leukemia, and more.
breast cancer; miRNA; biomarker; tumor; serum
The Guillain-Barré syndrome (GBS) is considered a T helper 1 (Th1) cells-mediated acute inflammatory peripheral neuropathy. However, some changes in GBS could not be explained completely by Th1 cells pathogenic role. Recently, Th17 cells have been identified and can mediate tissue inflammation and autoimmune response. Therefore, a study on the role of Th17 and Th22 cells and their cytokines in GBS is necessary for exploring the pathogenesis of GBS. Here, we detected the frequency of Th1, Th17, and Th22 cells by using 4-color flow cytometry and we detected the plasma levels of IL-17 and IL-22 by ELISA in GBS patients, relapsing-remitting multiple sclerosis patients at the acute phase of relapse, viral encephalitis or meningitis patients and healthy controls. Our data showed that the frequency of circulating Th1, Th17, and Th22 cells was significantly increased in GBS patients. The plasma levels of IL-17 and IL-22 in GBS and relapsing-remitting multiple sclerosis at the acute phase of relapse were also markedly elevated. Enhanced circulating Th22 cells were correlated with GBS severity. Intravenous immunoglobulin therapy downregulated Th17, and Th22 cells and the plasma levels of IL-17 and IL-22 in GBS patients. Th17 and Th22 cells may be involved in the pathogenesis of GBS, and intravenous immunoglobulin mediates therapeutic effects by downregulating these cells and their cytokines.
Emerging evidence indicates that the redistribution of phosphatidylethanolamine (PE) across the bilayer of the plasma membrane is an important molecular marker for apoptosis. However, the effect of PE on apoptosis and the underlying mechanism of PE remain unclear. In the current study, MTT and flow cytometric assays were used to examine the effects of PE on apoptosis in SMMC-7721 cells. The level of mitochondrial membrane potential (ΔΨm) and the expression of Bax, Bcl-2, caspase-3, phospho-Erk and phospho-Stat1/2 in SMMC-7721 cells that were exposed to PE were also investigated. The results showed that PE inhibited proliferation, caused G0/G1 phase cell cycle arrest and induced apoptosis in SMMC-7721 cells in a dose-dependent manner. Rhodamine 123 staining showed that the treatment of SMMC-7721 cells with different concentrations of PE for 24 h significantly decreased the level of ΔΨm and exerted dose-dependent effects. Using immunofluorescence and western blotting, we found that the expression of Bax was upregulated, whereas that of Bcl-2 was downregulated in PE-induced apoptotic cells. In addition, these events were accompanied by an increase in caspase-3 expression in a dose-dependent manner following PE treatment. PE-induced apoptosis was accompanied by a decrease in Erk phosphorylation and by the activation of Stat1/2 phosphorylation in SMMC-7721 cells. In conclusion, the results suggested that PE-induced apoptosis is involved in upregulating the Bax/Bcl-2 protein ratio and decreasing the ΔΨm. Moreover, the results showed that the Erk and Stat1/2 signalling pathways may be involved in the process of PE-induced apoptosis.
phosphatidylethanolamine; apoptosis; SMMC-7721 cells; Erk; Stat