Novel matrine derivative MD-1 attenuates hepatic fibrosis by inhibiting EGFR activation of hepatic stellate cells

Matrine (MT), the effective component of Sophora flavescens Ait, has been shown to have anti-inflammation, immune-suppressive, anti-tumor, and anti-hepatic fibrosis activities. However, the pharmacological effects of MT still need to be strengthened due to its relatively low efficacy and short half-life. In the present study, we report a more effective thio derivative of MT, MD-1, and its inhibitory effects on the activation of hepatic stellate cells (HSCs) in both cell culture and animal models. Cytological experiments showed that MD-1 can inhibit the proliferation of HSC-T6 cells with a half-maximal inhibitory concentration (IC50) of 62 μmol/L. In addition, MD-1 more strongly inhibits the migration of HSC-T6 cells compared to MT and can more effectively induce G0/G1 arrest and apoptosis. Investigating the biological mechanisms underlying anti-hepatic fibrosis in the presence of MD-1, we found that MD-1 can bind the epidermal growth factor receptor (EGFR) on the surface of HSC-T6 cells, which can further inhibit the phosphorylation of EGFR and its downstream protein kinase B (Akt), resulting in decreased expression of cyclin D1 and eventual inhibition of the activation of HSC-T6 cells. Furthermore, in rats with dimethylnitrosamine (DMN)-induced hepatic fibrosis, MD-1 slowed the development and progression of hepatic fibrosis, protecting hepatic parenchymal cells and improving hepatic functions. Therefore, MD-1 is a potential drug for anti-hepatic fibrosis.     

The potential of mesenchymal stem cells in the management of radiation enteropathy

Although radiotherapy is effective in managing abdominal and pelvic malignant tumors, radiation enteropathy is still unavoidable. This disease severely affects the quality of life of cancer patients due to some refractory lesions, such as intestinal ischemia, mucositis, ulcer, necrosis or even perforation. Current drugs or prevailing therapies are committed to alleviating the symptoms induced by above lesions. But the efficacies achieved by these interventions are still not satisfactory, because the milieus for tissue regeneration are not distinctly improved. In recent years, regenerative therapy for radiation enteropathy by using mesenchymal stem cells is of public interests. Relevant results of preclinical and clinical studies suggest that this regenerative therapy will become an attractive tool in managing radiation enteropathy, because mesenchymal stem cells exhibit their pro-regenerative potentials for healing the injuries in both epithelium and endothelium, minimizing inflammation and protecting irradiated intestine against fibrogenesis through activating intrinsic repair actions. In spite of these encouraging results, whether mesenchymal stem cells promote tumor growth is still an issue of debate. On this basis, we will discuss the advances in anticancer therapy by using mesenchymal stem cells in this review after analyzing the pathogenesis of radiation enteropathy, introducing the advances in managing radiation enteropathy using regenerative therapy and exploring the putative actions by which mesenchymal stem cells repair intestinal injuries. At last, insights gained from the potential risks of mesenchymal stem cell-based therapy for radiation enteropathy patients may provide clinicians with an improved awareness in carrying out their studies.     

Probe droplet arrays generated in the capillary for microarray analysis

Microarray technology is a useful tool for nucleic acid detection and has been widely used in biology and related research fields. However, the procedure is labor intensive and time consuming. Microfluidic chip-based microarrays save time with better performance, but the low spot density and probe number limit its applications. To develop high performance microarrays with high spot density within a microchannel, a method is reported here for preparing microarrays in a capillary by generating probe droplet arrays. The probes in droplets are immobilized onto the inner wall of the capillary to form a one-dimensional probe array, and then a sample solution is introduced to hybridize with the probe array. The effect of the capillary's inner diameter was evaluated to realize a high-density probe array. The processes of array generation and probe immobilization were studied to avoid possible cross contamination. The background from probe immobilization during the array generation and incubation was quantified to assure sensitivity. Multiple sample detection was also demonstrated within one capillary. The capillary based microarray assay had high spot density, easy fabrication, fast detection, high sensitivity and multiple sample capacity.     

Industrial process proteomics: alfalfa protein patterns during wet fractionation processing

A proteome reference map of major soluble proteins from Medicago sativa (alfalfa) leaves and stems has been established for the first time. Among 195 spots analyzed by mass spectrometry and N-terminal Edman sequencing, 117 spots were unambiguously identified, representing 87 different proteins. Of these 87 proteins, 13 proteins were directly identified from the partial genome of Medicago sativa, 30 from expressed sequenced tags (ESTs) of the model legume Medicago truncatula and 44 from closely relative species by a cross-species protein identification method. The proteome map of Medicago sativa was then set as a reference to study the major high protein content products that are generated during the wet fractionation process of alfalfa green biomass. Using two-dimensional electrophoresis, we studied the variation of the protein patterns at different steps of the industrial-scale process. We clearly show that the process induces significant changes including chemical modifications, proteolytic events, and heat-shock protein responses. Strikingly, a certain level of cellular regulation is conserved during biomass processing, as exemplified by the induction of some heat shock proteins. Finally, all the results obtained in this proteomic study may help to identify novel products and to improve process designs in alfalfa biomass plants.     

Carbohydrate-based micelle clusters which enhance hydrophobic drug bioavailability by up to 1 order of magnitude

Amphiphilic chitosan-based polymers (Mw < 20 kDa) self-assemble in aqueous media at low micromolar concentrations to give previously unknown micellar clusters of 100-300 nm in size. Micellar clusters comprise smaller 10-30 nm aggregates, and the nanopolarity/drug incorporation efficiency of their hydrophobic domains can be tailored by varying the degree of lipidic derivatization and molecular weight of the carbohydrate. The extent of drug incorporation by these novel micellar clusters is 1 order of magnitude higher than is seen with triblock copolymers, with molar polymer/drug ratios of 1:48 to 1:67. On intravenous injection, the pharmacodynamic activity of a carbohydrate propofol formulation is increased by 1 order of magnitude when compared to a commercial emulsion formulation, and on topical ocular application of a carbohydrate prednisolone formulation, initial drug aqueous humor levels are similar to those found with a 10-fold dose of prednisolone suspension.     

The Role of Nucleus Accumbens Core/Shell in Sleep-Wake Regulation and their Involvement in Modafinil-Induced Arousal

Background

We have previously shown that modafinil promotes wakefulness via dopamine receptor D₁ and D₂ receptors; however, the locus where dopamine acts has not been identified. We proposed that the nucleus accumbens (NAc) that receives the ventral tegmental area dopamine inputs play an important role not only in reward and addiction but also in sleep-wake cycle and in mediating modafinil-induced arousal.

Methodology/Principal Findings

In the present study, we further explored the role of NAc in sleep-wake cycle and sleep homeostasis by ablating the NAc core and shell, respectively, and examined arousal response following modafinil administration. We found that discrete NAc core and shell lesions produced 26.5% and 17.4% increase in total wakefulness per day, respectively, with sleep fragmentation and a reduced sleep rebound after a 6-hr sleep deprivation compared to control. Finally, NAc core but not shell lesions eliminated arousal effects of modafinil.

Conclusions/Significance

These results indicate that the NAc regulates sleep-wake behavior and mediates arousal effects of the midbrain dopamine system and stimulant modafinil.     

Accuracy of Ultrasonography and Magnetic Resonance Imaging in the Diagnosis of Placenta Accreta

Purpose

To evaluate the accuracy of ultrasonography and magnetic resonance imaging (MRI) in the diagnosis of placenta accreta and to define the most relevant specific ultrasound and MRI features that may predict placental invasion.

Material and Methods

This study was approved by the institutional review board of the French College of Obstetricians and Gynecologists. We retrospectively reviewed the medical records of all patients referred for suspected placenta accreta to two university hospitals from 01/2001 to 05/2012. Our study population included 42 pregnant women who had been investigated by both ultrasonography and MRI. Ultrasound images and MRI were blindly reassessed for each case by 2 raters in order to score features that predict abnormal placental invasion.

Results

Sensitivity in the diagnosis of placenta accreta was 100% with ultrasound and 76.9% for MRI (P = 0.03). Specificity was 37.5% with ultrasonography and 50% for MRI (P = 0.6). The features of greatest sensitivity on ultrasonography were intraplacental lacunae and loss of the normal retroplacental clear space. Increased vascularization in the uterine serosa-bladder wall interface and vascularization perpendicular to the uterine wall had the best positive predictive value (92%). At MRI, uterine bulging had the best positive predictive value (85%) and its combination with the presence of dark intraplacental bands on T2-weighted images improved the predictive value to 90%.

Conclusion

Ultrasound imaging is the mainstay of screening for placenta accreta. MRI appears to be complementary to ultrasonography, especially when there are few ultrasound signs.     

Apocynin attenuates renal fibrosis via inhibition of NOXs-ROS-ERK-myofibroblast accumulation in UUO rats

Background: Oxidative stress has been identified as an important pathogenesis mechanism in the development of renal interstitial fibrosis in unilateral ureteral obstruction (UUO). Previous studies have demonstrated increased expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOXs) in response to UUO. We aimed to investigate whether NOXs activation was involved in the development of renal fibrosis in UUO by contribution to oxidative stress and the potential mechanism in the present study.

Methods: Apocynin, a NOXs inhibitor, was initiated immediately by gavage after UUO was performed on Wistar rats and continued until 7 days after UUO. Changes of markers of oxidative stress, renal macrophage infiltration and fibrosis, TGF-β1 expression, NOXs expression and activity, and ERK activation were evaluated.

Results: Apocynin significantly attenuated the activity of NOXs, accompanied with decreased expression of NOX2, NOX4, and oxidative stress markers in the obstructed kidneys of UUO. Additionally, collagen deposition and renal fibrosis induced by UUO were attenuated by apocynin treatment. Furthermore, apocynin treatment significantly attenuated the phosphorylation of ERK, accumulation of myofibroblast and infiltration of macrophage in obstructed kidneys. No significant effect of apocynin on UUO-induced increased TGF-β1 expression could be observed. And there was no significant change of anti-oxidants enzyme activities in the obstructed kidneys of apocynin-treated rats.

Conclusions: These results suggested that apocynin might exert beneficial effects on renal fibrosis by inhibition of NOXs activation and subsequent reduction of oxidative stress, ERK activation, and myofibroblast accumulation in UUO rats. Targeting NOXs may serve as a therapeutic strategy for the treatment of renal fibrosis.