MicroRNAs (miRNAs) are a class of 20–24 nt non-coding RNAs that regulate gene expression primarily through post-transcriptional repression or mRNA degradation in a sequence-specific manner. The roles of miRNAs are just beginning to be understood, but the study of miRNA function has been limited by poor understanding of the general principles of gene regulation by miRNAs. Here we used CNE cells from a human nasopharyngeal carcinoma cell line as a cellular system to investigate miRNA-directed regulation of VEGF and other angiogenic factors under hypoxia, and to explore the principles of gene regulation by miRNAs. Through computational analysis, 96 miRNAs were predicted as putative regulators of VEGF. But when we analyzed the miRNA expression profile of CNE and four other VEGF-expressing cell lines, we found that only some of these miRNAs could be involved in VEGF regulation, and that VEGF may be regulated by different miRNAs that were differentially chosen from 96 putative regulatory miRNAs of VEGF in different cells. Some of these miRNAs also co-regulate other angiogenic factors (differential regulation and co-regulation principle). We also found that VEGF was regulated by multiple miRNAs using different combinations, including both coordinate and competitive interactions. The coordinate principle states that miRNAs with independent binding sites in a gene can produce coordinate action to increase the repressive effect of miRNAs on this gene. By contrast, the competitive principle states when multiple miRNAs compete with each other for a common binding site, or when a functional miRNA competes with a false positive miRNA for the same binding site, the repressive effects of miRNAs may be decreased. Through the competitive principle, false positive miRNAs, which cannot directly repress gene expression, can sometimes play a role in miRNA-mediated gene regulation. The competitive principle, differential regulation, multi-miRNA binding sites, and false positive miRNAs might be useful strategies in the avoidance of unwanted cross-action among genes targeted by miRNAs with multiple targets.
Gut microbes play important roles in regulating fat storage and metabolism. Rhizoma coptidis (RC) and its main active compound, berberine, have either antimicrobial or anti-obesity activities. In the present study, we hypothesize that RC exerts anti-obesity effects that are likely mediated by mechanisms of regulating gut microbes and berberine may be a key compound of RC. Gut microbes and glucose and lipid metabolism in high-fat diet-fed C57BL/6J (HFD) mice in vivo are investigated after RC and berberine treatments. The results show that RC (200 mg/kg) and berberine (200 mg/kg) significantly lower both body and visceral adipose weights, and reduce blood glucose and lipid levels, and decrease degradation of dietary polysaccharides in HFD mice. Both RC and berberine significantly reduce the proportions of fecal Firmicutes and Bacteroidetes to total bacteria in HFD mice. In the trial ex vivo, both RC and berberine significantly inhibit the growth of gut bacteria under aerobic and anaerobic conditions. In in vitro trials, both RC and berberine significantly inhibit the growth of Lactobacillus (a classical type of Firmicutes) under anaerobic conditions. Furthermore, both RC and berberine significantly increase fasting-induced adipose factor (Fiaf, a key protein negatively regulated by intestinal microbes) expressions in either intestinal or visceral adipose tissues. Both RC and berberine significantly increase mRNA expressions of AMPK, PGC1α, UCP2, CPT1α, and Hadhb related to mitochondrial energy metabolism, which may be driven by increased Fiaf expression. These results firstly suggest that antimicrobial activities of RC and berberine may result in decreasing degradation of dietary polysaccharides, lowering potential calorie intake, and then systemically activating Fiaf protein and related gene expressions of mitochondrial energy metabolism in visceral adipose tissues. Taken together, these action mechanisms may contribute to significant anti-obesity effects. Findings in the present study also indicate that pharmacological regulation on gut microbes can develop an anti-obesity strategy.
Surface plasmon resonance (SPR) biosensor is a powerful tool for studying the kinetics of biomolecular interactions because they offer unique real-time and label-free measurement capabilities with high detection sensitivity. In the past two decades, SPR technology has been successfully commercialized and its performance has continuously been improved with lots of engineering efforts. In this review, we describe the recent advances in SPR technologies. The developments of SPR technologies focusing on detection speed, sensitivity, and portability are discussed in details. The incorporation of imaging techniques into SPR sensing is emphasized. In addition, our SPR imaging biosensors based on the scanning of wavelength by a solid-state tunable wavelength filter are highlighted. Finally, significant advances of the vast developments in nanotechnology-associated SPR sensing for sensitivity enhancements are also reviewed. It is hoped that this review will provide some insights for researchers who are interested in SPR sensing, and help them develop SPR sensors with better sensitivity and higher throughput.
BackgroundA risk-reduction treatment programme complemented by a focused assessment, both guided by the risk–need–responsivity principles, is suggested as the preferred treatment for violence-prone individuals with personality disorder.AimsViolence Reduction Programme (VRP) and Violence Risk Scale (VRS) were used to illustrate the design and implementation of such an approach. Participants from a similarly designed Aggressive Behaviour Control Programme were used to illustrate the principles discussed and to test programme efficacy.MethodThe VRS was used to assess risk/need and treatment readiness, and DSM–III/IV psychiatric diagnoses of 203 federal offenders.ResultsParticipants had a high probability of violent recidivism and many violence-linked criminogenic needs, similar to offenders with high PCL–R scores. Most had antisocial personality disorder and substance use disorders; in terms of treatment-readiness, most were in the contemplation stage of change. Outcome evaluation results support the objectives of the VRP.ConclusionsIntegrating risk–need–responsivity principles in assessment and treatment can provide useful guidelines for intervention with violence-prone forensic clients with personality disorder.
Objectives: Pathological biomarkers and mechanisms of dengue infection are poorly understood. We investigated a new serum biomarker using miRNAs and performed further correlation analysis in dengue-infected patients.Methods: Expression levels of broad-spectrum miRNAs in serum samples from three patients with dengue virus type 1 (DENV-1) and three healthy volunteers were separately analyzed using miRNA PCR arrays. The expressions of the five selected miRNAs were verified by qRT-PCR in the sera of 40 DENV-1 patients and compared with those from 32 healthy controls. Receiver operating characteristic (ROC) curve and correlation analyses were performed to evaluate the potential of these miRNAs for the diagnosis of dengue infection.Results: MiRNA PCR arrays revealed that 41 miRNAs were upregulated, whereas 12 miRNAs were down-regulated in the sera of DENV-1 patients compared with those in healthy controls. Among these miRNAs, qRT-PCR validation showed that serum hsa-miR-21-5p, hsa-miR-590-5p, hsa-miR-188-5p, and hsa-miR-152-3p were upregulated, whereas hsa-miR-146a-5p was down-regulated in dengue-infected patients compared with healthy controls. ROC curves showed serum hsa-miR-21-5p and hsa-miR-146a-5p could distinguish dengue-infected patients with preferable sensitivity and specificity. Correlation analysis indicated that expression levels of serum hsa-miR-21-5p and hsa-miR-146a-5p were negative and positively correlated with the number of white blood cells and neutrophils, respectively. Functional analysis of target proteins of these miRNAs in silico indicated their involvement in inflammation and cell proliferation.Conclusion: Dengue-infected patients have a broad “fingerprint” profile with dysregulated serum miRNAs. Among these miRNAs, serum hsa-miR-21-5p, hsa-miR-146a-5p, hsa-miR-590-5p, hsa-miR-188-5p, and hsa-miR-152-3p were identified as promising serum indicators for dengue infection.
[with no lysine (k)] kinase is a serine/threonine kinase subfamily. Mutations in two of the WNK kinases result in pseudohypoaldosteronism type II (PHA II) characterized by hypertension, hyperkalemia, and metabolic acidosis. Recent studies showed that both WNK1 and WNK4 inhibit ROMK activity. However, little is known about the effect of WNK kinases on Maxi K, a large-conductance Ca 2ϩ and voltage-activated potassium (K) channel. Here, we report that WNK4 wild-type (WT) significantly inhibits Maxi K channel activity in HEK ␣BK stable cell lines compared with the control group. However, a WNK4 dead-kinase mutant, D321A, has no inhibitory effect on Maxi K activity. We further found that WNK4 inhibits total and cell surface protein expression of Maxi K equally compared with control groups. A dominant-negative dynamin mutant, K44A, did not alter the WNK4-mediated inhibitory effect on Maxi K surface expression. Treatment with bafilomycin A1 (a proton pump inhibitor) and leupeptin (a lysosomal inhibitor) reversed WNK4 WT-mediated inhibition of Maxi K total protein expression. These findings suggest that WNK4 WT inhibits Maxi K activity by reducing Maxi K protein at the membrane, but that the inhibition is not due to an increase in clathrin-mediated endocytosis of Maxi K, but likely due to enhancing its lysosomal degradation. Also, WNK4's inhibitory effect on Maxi K activity is dependent on its kinase activity. protein expression; lysosomal degradation WNK [WITH NO LYSINE (K)] KINASE belongs to a subfamily of serine/threonine kinases (55). Mutations in two members of this family, WNK1 and WNK4, result in pseudohypoaldosteronism type II (PHA II). PHA II, also referred to as Gordon's syndrome, is an autosomal dominant disorder, characterized by hypertension, hyperkalemia, and metabolic acidosis (51). This clinical phenotype suggests that WNK kinases might regulate renal potassium (K) channels, such as renal outer medullary potassium channel (ROMK) or Maxi K channels (BK channels) that are responsible for K handling by the distal nephron. A number of studies indicate that WNK kinases constitute a novel signaling pathway that is involved in the regulation of different ion transporters and channels controlling sodium and K homeostasis (23). In kidney tissue, there are two types of apical K channels identified in the distal nephron by patchclamp analysis (38). One type of K channel is a low-conductance secretory K (SK) channel that has high open probability at resting membrane potential and mediates K ϩ secretion under basal conditions. The properties of the SK channel are consistent with those of ROMK. The other type of K channel has a high single-channel conductance (Ͼ100 pS) and channel kinetics similar to Maxi K channels (34). Although it is generally accepted that ROMK is the K ϩ secretory channel in the mammalian distal nephron, recent in vitro and in vivo studies have provided evidence that Maxi K can also serves as a K ϩ secretory channel in renal tubules (37) and that it plays an important role in K ϩ secretion in ROM...
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