Effects of Bisphenol A Metabolite 4-Methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene on Lung Function and Type 2 Pulmonary Alveolar Epithelial Cell Growth

Bisphenol A (BPA) is recognized as a major pollutant worldwide. 4-Methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP) is a major active metabolite of BPA. The epidemiological and animal studies have reported that BPA is harmful to lung function. The role of MBP in lung dysfunction after BPA exposure still remains unclear. This study investigated whether MBP would induce lung alveolar cell damage and evaluated the role of MBP in the BPA exposure-induced lung dysfunction. An in vitro type 2 alveolar epithelial cell (L2) model and an ex vivo isolated reperfused rat lung model were used to determine the effects of BPA or MBP on cell growth and lung function. MBP, but not BPA, dose-dependently increased the mean artery pressure (Pa), pulmonary capillary pressure (Pc), pulmonary capillary filtration coefficient (K_fc), and wet/dry weight ratio in isolated reperfused rat lungs. MBP significantly reduced cell viability and induced caspases-3/7 cleavage and apoptosis and increased AMP-activated protein kinas (AMPK) phosphorylation and endoplasmic reticulum (ER) stress-related molecules expression in L2 cells, which could be reversed by AMPK-siRNA transfection. These findings demonstrated for the first time that MBP exposure induced type 2 alveolar cell apoptosis and lung dysfunction through an AMPK-regulated ER stress signaling pathway.

Nucleoplasty for treating lumbar disk degenerative low back pain: an outcome prediction analysis

Purpose

Nucleoplasty is a minimally invasive technique that is considered efficacious in alleviating lumbar disk degenerative low back pain (LBP). The efficacy of nucleoplasty and identified variables that can predict pain relief for nucleoplasty was reported.

Patients and methods

Between December 2013 and November 2015, 47 nucleoplasty procedures on 47 lumbar disks in 31 consecutive patients were performed. The outcome was evaluated using a visual analog scale (VAS) score. Improvements of ≥50% in VAS scores were considered substantial pain relief. The variables associated with pain relief after nucleoplasty included: 1) age; 2) sex; 3) body mass index; 4) hyperintensity zone at the rear of the disk; 5) hypointensity of the disk; 6) Modic changes of the end plates; 7) spinal instability pain; and 8) discography results.

Results

Twenty-one patients (67.7%) experienced substantial pain relief. The most common side effects following nucleoplasty were soreness at the needle puncture site (64.5%), numbness in the lower leg (12.9%), and increased intensity of back pain (9.7%). All side effects were transient. Multivariate analysis revealed that the discography results were the most critical predictor for substantial pain relief of nucleoplasty (P=0.03). The sensitivity and specificity of discography were 92.8% and 62.5%, respectively.

Conclusion

Discography results could improve the success rate of nucleoplasty in the treatment of disk degenerative LBP.

Insulin-like growth factor-independent insulin-like growth factor binding protein 3 promotes cell migration and lymph node metastasis of oral squamous cell carcinoma cells by requirement of integrin β1

Frequent metastasis to the cervical lymph nodes leads to poor survival of patients with oral squamous cell carcinoma (OSCC). To understand the underlying mechanisms of lymph node metastasis, two sublines were successfully isolated from cervical lymph nodes of nude mice through in vivo selection, and identified as originating from poorly metastatic parental cells. These two sublines specifically metastasized to cervical lymph nodes in 83% of mice, whereas OEC-M1 cells did not metastasize after injection into the oral cavity. After gene expression analysis, we identified insulin-like growth factor binding protein 3 (IGFBP3) as one of the significantly up-regulated genes in the sublines in comparison with their parental cells. Consistently, meta-analysis of the public microarray datasets and IGFBP3 immunohistochemical analysis revealed increased both levels of IGFBP3 mRNA and protein in human OSCC tissues when compared to normal oral or adjacent nontumorous tissues. Interestingly, the up-regulated IGFBP3 mRNA expression was significantly associated with OSCC patients with lymph node metastasis. IGFBP3 knockdown in the sublines impaired and ectopic IGFBP3 expression in the parental cells promoted migration, transendothelial migration and lymph node metastasis of orthotopic transplantation. Additionally, ectopic expression of IGFBP3 with an IGF-binding defect sustained the IGFBP3-enhanced biological functions. Results indicated that IGFBP3 regulates metastasis-related functions of OSCC cells through an IGF-independent mechanism. Furthermore, exogenous IGFBP3 was sufficient to induce cell motility and extracellular signal-regulated kinase (ERK) activation. The silencing of integrin β1 was able to impair exogenous IGFBP3-mediated migration and ERK phosphorylation, suggesting a critical role of integrin β1 in IGFBP3-enchanced functions.

Reduction of adhesions and antrostomy stenosis with topical vitamin A after endoscopic sinus surgery

BACKGROUND

Prevention of adhesion formation and restoration of mucociliary mucosa are major determinants of the success of endoscopic sinus surgery (ESS). Vitamin A (VA) can promote mucociliary differentiation of respiratory epithelium. However, whether topical VA can promote sinonasal wound healing or reduce adhesion formation after ESS in humans remains unexplored.

OBJECTIVE

To investigate the effect of topical VA on sinonasal wound healing and adhesion formation after ESS.

METHODS

This is a within-subject control study. Patients with chronic rhinosinusitis were included. Each patient underwent ESS, and topical VA was applied over the sinonasal wound. Postoperative outcomes were assessed by using the Lund-Kennedy score, and the antrostomy size was measured. In vitro wound healing assay of fibroblasts with or without VA was evaluated. Restoration of ciliated epithelium was examined by using scanning electron microscopy.

RESULTS

Thirty patients were enrolled. The mean (standard deviation {SD}) scores for scarring/adhesion in the VA-treated side at 3 and 12 months after surgery (0.20 ± 0.40 and 0.23 ± 0.42, respectively) were significantly lower than those in the controls (0.47 ± 0.50 and 0.53 ± 0.62, respectively). The mean (SD) antrostomy size in the VA treated side at 1, 3, and 12 months after surgery (0.85 ± 0.30 cm(2), 0.7 ± 0.30 cm(2), and 0.70 ± 0.27 cm(2), respectively) were significantly larger than those in the controls (0.79 ± 0.26 cm(2), 0.60 ± 0.25 cm(2), and 0.57 ± 0.24 cm(2), respectively). Wound healing assay revealed that VA significantly inhibited the proliferation and migration of fibroblasts. Scanning electron microscopy showed mature ciliated cells in the VA-treated side.

CONCLUSION

Topical VA is a promising agent for sinonasal wound healing after ESS because it can promote mucociliary reepithelization, reduce adhesion, and prevent antrostomy stenosis.

[Report and analysis of 2 cases of nerve paralysis with aspiration pneumonia after infection of herpes zoster virus]

Two cases of patients were hospitalized for sore throat with Dysphagia.Check:Wall of the pharynx,tongue and epiglottis scattered the ulcer.The patients were loss of pharynx reflex.Oropharynx and piriform fossa has a lot of saliva retention.Posterior pharyngeal wall was drooping like waterfull.CT scan showed may be the aspiration pneumonia in right lower lung.The admission diagnosiswere pharyngeal herpes zoster virus infection,pharyngeal side muscle paralysis,and inhalation pneumonia.The patients' clinical data were retrospectively analyzed,and the report is as follows.

Combined promoting effects of low-Pd-containing and Cu-doped LaCoO3 perovskite supported on cordierite for the catalytic combustion of benzene

The catalytic activities for benzene oxidation and resistance to SO2 poisoning were tested for a series of Pd/La-Cu-Co-O/cordierite catalysts, which were prepared using a multiple-step impregnation method. The XRD, SEM, and IR characterization techniques were performed to investigate the relationship between the catalytic performance and its physicochemical properties. When Pd/La-Cu-Co-O/cordierite catalysts with Pd loadings of 0.06 and 0.08 % were prepared at a calcination temperature of 500 °C for 5 h, they exhibited similar catalytic activity and sulfur resistance. When the concentration of benzene was 1500 ppm and the GHSV was 20000 h(-1), the benzene conversion was above 95 % at a reaction temperature of 350 °C in SO2 existing at 100 ppm. These results were mainly attributed to the cooperation between La-Cu-Co-O perovskite and the noble metal Pd. Specifically, the addition of copper can strengthen the catalytic activity of La-Co-O/cordierite catalysts by decreasing the crystalline size of the active ingredients. A moderate Pd addition can drastically improve the sulfur resistance and further improve the catalytic activity of the La-Cu-Co-O/cordierite catalyst.

Fluoroscopically Guided C2 Percutaneous Vertebroplasty: A Surgical Technique Note on an Anterior Ascending Approach

BACKGROUND

C2 vertebroplasty is more challenging than transpedicular percutaneous vertebroplasty in the thoracic and lumbar spine.

OBJECTIVE

We report an anterior ascending approach for C2 percutaneous vertebroplasty to avoid potential injury to vital structures surrounding the C2 vertebra.

STUDY DESIGN

A technique note with 5 consecutive cases.

SETTING

Neurosurgery department of a university hospital.

METHODS

Fluoroscopically guided manual compression was applied using 3 fingers at the C5 level between the muscle and trachea. The larynx and trachea were displaced medially and the carotid artery laterally. The anterior cervical spine was palpated, and a 15-gauge 4-inch bone marrow biopsy needle was introduced through an anterior ascending approach. When the tip touched the intervertebral disc between C2 and C3, the needle was pushed through the disc until it penetrated into the C2 vertebral body. After confirming adequate needle insertion, vertebroplasty was performed.

RESULTS

Pain relief was achieved in 4/5 (80%) patients. One patient possibly did not benefit from percutaneous vertebroplasty, and asymptomatic cement extravasation was detected in 2 patients.

LIMITATIONS

Sample size; impossibility of placebo control.

CONCLUSION

An anterior ascending approach for C2 percutaneous vertebroplasty is a valuable alternative for relieving pain caused by metastatic spinal tumors. This approach is familiar to surgeons performing anterior cervical discectomies, percutaneous nucleoplasty, or odontoid screw placement surgeries.

KEY WORDS

Vertebroplasty, pain, axis, cement leak, metastases, palliative medicine, spine, fracture.

Osteoclastogenesis in Local Alveolar Bone in Early Decortication-Facilitated Orthodontic Tooth Movement

Objective

In the current study, we aimed to investigate the effects of alveolar decortication on local bone remodeling, and to explore the possible mechanism by which decortication facilitates tooth movement.

Materials and Methods

Forty rabbits were included in the experiment. The left mandible was subjected to decortication-facilitated orthodontics, and the right mandible underwent traditional orthodontics as a control. The animals were sacrificed on the days 1, 3, 5, 7 and 14, after undergoing orthodontic procedures. Tooth movement was measured by Micro-CT, and the local periodontal tissues were investigated using H&E, Masson's trichrome and tartrate-resistant acid phosphatase (TRAP) staining. The mRNA levels of genes related to bone remodeling in the alveolar bone were analyzed using real-time PCR.

Result

On days 3, 5, 7 and 14, tooth movement was statistically accelerated by decortication (P < 0.05) and was accompanied by increased hyperemia. Despite the lack of new bone formation in both groups, more osteoclasts were noted in the decorticated group, with two peak counts (P < 0.05). The first peak count was consistent with the maximum values of ctsk and TRAP expression, and the second peak counts accompanied the maximum nfatc1 and jdp2 expression. The increased fra2 expression and the ratio of rankl/opg also accompanied the second peak counts.

Conclusions

Following alveolar decortication, osteoclastogenesis was initially induced to a greater degree than the new bone formation which was thought to have caused a regional acceleratory phenomenon (RAP). The amount of steoclastogenesis in the decorticated alveolar bone was found to have two peaks, perhaps due to attenuated local resistance. The first peak count in osteoclasts may have been due to previously existing osteoclast precursors, whereas the second may represent the differentiation of peripheral blood mononuclear cells which came from circulation as the result of hyperemia.

[Binding characteristics of chemosynthetic Ac-SDKP analogue FAM-Aca-SDKP to hepatic stellate cell-T6 cells]

OBJECTIVE

To investigate the binding of the chemosynthetic analogue of N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) FAM-Aca-SDKP to hepatic stellate cell-T6 (HSC-T6) cells and basic physical characteristics.

METHODS

The Ac-SDKP analogue short-peptide FAM-Aca-SDKP carrying green fluorescence was synthesized chemically. Quantitative real-time PCR was used to evaluate its effect on the secretion of HSC collagen and verify the consistency in the biological effect between FAM-Aca-SDKP and Ac-SDKP. A fluorescence microscope was used to observe the binding between FAM-Aca-SDKP and HSC-T6, and flow cytometry was used to evaluate the time-concentration effect of the binding between FAM-Aca-SDKP and HSC-T6. The t-test or rank sum test was used for the statistical analysis of different types of data.

RESULTS

After HSC-T6 was incubated with Ac-SDKP or FAM-Aca-SDKP for 24 hours, the expression of type I collagen in HSC-T6 was increased, when the action time was 0.5 hour, Ac-SDKP and FAM-Aca-SDKP caused a 30%-50% reduction in the expression of type I collagen. After HSC-T6 was incubated with FAM-Aca-SDKP, strong green fluorescence was observed on cell surface under a fluorescence microscope, and after Ac-SDKP was added, Ac-SDKP significantly reduced the fluorescence intensity on cell surface due to competitive inhibition. Flow cytometry showed that when the concentration of FAM-Aca-SDKP was 0-50μmol/L, the rate of fluorescence-positive cells rapidly increased from 0 to 12%; when the concentration was 50-100μmol/L, the rate of fluorescence-positive cells only increased from 12% to 14%; co-incubation with Ac-SDKP significantly reduced the rate of fluorescence-positive cells. The number of positive cells reached the peak at the 45-minute point of the incubation and then decreased gradually.

CONCLUSIONS

FAM-Aca-SDKP can bind to the surface of HSC-T6 cells, and this process has ligand-receptor binding characteristics such as competitive inhibition, saturability, and time-concentration effect.

[One case in which papillary thyroid carcinoma and papillary carcinoma occur on the same side]

thyroid carcinoma is a common tumor in the endocrine system. There are four common types of thyroid carcinoma: papillary carcinoma; follicular cancer; medullary carcinoma; undifferentiated carcinoma. Thyroid papillary carcinoma is derived from follicular epithelial cells, which is different from that of medullary thyroid carcinoma. If both occur in the same side of the thyroid gland, this is very rare. In this paper we report a case in which papillary thyroid carcinoma and papillary carcinoma occurr on the same side.

Specific detection of CD133-positive tumor cells with iron oxide nanoparticles labeling using noninvasive molecular magnetic resonance imaging

Background

The use of ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles to visualize cells has been applied clinically, showing the potential for monitoring cells in vivo with magnetic resonance imaging (MRI). USPIO conjugated with anti-CD133 antibodies (USPIO-CD133 Ab) that recognize the CD133 molecule, a cancer stem cell marker in a variety of cancers, was studied as a novel and potent agent for MRI contrast enhancement of tumor cells.

Materials and methods

Anti-CD133 antibodies were used to conjugate with USPIO via interaction of streptavidin and biotin for in vivo labeling of CD133-positive cells in xenografted tumors and N-ethyl-N-nitrosourea (ENU)-induced brain tumors. The specific binding of USPIO-CD133 Ab to CD133-positive tumor cells was subsequently detected by Prussian blue staining and MRI with T2-weighted, gradient echo and multiple echo recombined gradient echo images. In addition, the cellular toxicity of USPIO-CD133 Ab was determined by analyzing cell proliferation, apoptosis, and reactive oxygen species production.

Results

USPIO-CD133 Ab specifically recognizes in vitro and labels CD133-positive cells, as validated using Prussian blue staining and MRI. The assays of cell proliferation, apoptosis, and reactive oxygen species production showed no significant differences in tumor cells with or without labeling of USPIO-CD133 Ab. In vivo imaging of CD133-positive cells was demonstrated by intravenous injection of USPIO-CD133 Ab in mice with HT29 xenografted tumors. The MRI of HT29 xenografts showed several clusters of hypotensive regions that correlated with CD133 expression and Prussian blue staining for iron. In rat, brain tumors induced by transplacental ENU mutagenesis, several clusters of hypointensive zones were observed in CD133-expressing brain tumors by MRI and intravenously administered USPIO-CD133 Ab.

Conclusion

Combination of USPIO-CD133 Ab and MRI is valuable in recognizing CD133-expressing tumor cells in vitro, extracellularly labeling for cell tracking and detecting CD133-expressing tumors in xenografted tumors as well as ENU-induced rat brain tumors.

Unconventional interplay between heterovalent dopant elements: Switch-and-modulator band-gap engineering in (Y, Co)-Codoped CeO2 nanocrystals

We report the experimental observation and theoretical explanation of an unconventional interplay between divalent Co and trivalent Y dopants, both of which incur oxygen vacancies in the CeO₂ host that has predominantly tetravalent Ce cations. The Co dopant atoms were experimentally found to act as a switch that turns on the dormant effect of Y-modulated band-gap reduction. As revealed by density functional theory (DFT) calculations with structures verified by synchrotron-radiation x-ray measurements, a Co 3d band that hybridizes with Ce 4f band was lowered due to reduced O 2p repulsion arising from oxygen vacancies incurred by Y doping and therefore gave rise to the observed band-gap narrowing effect. Such switch-and-modulator scheme for band-gap engineering in nanocrystal materials can lead to important applications in environmental protection and solar energy harvesting technologies.

Novel peptides suppress VEGFR-3 activity and antagonize VEGFR-3-mediated oncogenic effects

Vascular endothelial growth factor receptor 3 (VEGFR-3) supports tumor lymphangiogenesis. It was originally identified as a lymphangiogenic factor expressed in lymphatic endothelial cells. VEGFR-3 was detected in advanced human malignancies and correlated with poor prognosis. Our previous studies show that activation of the VEGF-C/VEGFR-3 axis promotes cancer metastasis and is associated with clinical progression in patients with lung cancer, indicating that VEGFR-3 is a potential target for cancer therapy. In this study, we developed eight peptides targeting VEGFR-3. Two peptides strongly inhibited the kinase activity of VEGFR-3 and suppressed VEGF-C-mediated invasion of cancer cells. Moreover, these peptides abolished VEGF-C-induced drug resistance and tumor initiating cell formation. This study demonstrates the therapeutic potential of VEGFR-3-targeting peptides.

Pulsed radiofrequency treatment of articular branches of femoral and obturator nerves for chronic hip pain

Purpose

Chronic hip pain is a common symptom experienced by many people. Often, surgery is not an option for patients with multiple comorbidities, and conventional drugs either have many side effects or are ineffective. Pulsed radiofrequency (PRF) is a new method in the treatment of pain. We attempt to compare the efficacy of PRF relative to conservative management for chronic hip pain.

RPatients and methods

Between August 2011 and July 2013, 29 patients with chronic hip pain were divided into two groups (PRF and conservative treatment) according to consent or refusal to undergo PRF procedure. Fifteen patients received PRF of the articular branches of the femoral and obturator nerves, and 14 patients received conservative treatment. Visual analog scale (VAS), Oxford hip scores (OHS), and pain medications were used for outcome measurement before treatment and at 1 week, 4 weeks, and 12 weeks after treatment.

Results

At 1 week, 4 weeks, and 12 weeks after treatment initiation, improvements in VAS were significantly greater with PRF. Improvements in OHS were significantly greater in the PRF group at 1 week, 4 weeks, and 12 weeks. Patients in the PRF group also used less pain medications. Eight subjects in the conservative treatment group switched to the PRF group after 12 weeks, and six of them had >50% improvement.

Conclusion

When compared with conservative treatment, PRF of the articular branches of the femoral and obturator nerves offers greater pain relief for chronic hip pain and can augment physical functioning.

The in vitro generation of lung and airway progenitor cells from human pluripotent stem cells

Lung and airway epithelial cells generated in vitro from human pluripotent stem cells (hPSCs) have applications in regenerative medicine, modeling of lung disease, drug screening and studies of human lung development. Here we describe a strategy for directed differentiation of hPSCs into developmental lung progenitors, and their subsequent differentiation into predominantly distal lung epithelial cells. The protocol entails four stages that recapitulate lung development, and it takes ∼50 d. First, definitive endoderm (DE) is induced in the presence of high concentrations of activin A. Subsequently, lung-biased anterior foregut endoderm (AFE) is specified by sequential inhibition of bone morphogenetic protein (BMP), transforming growth factor-β (TGF-β) and Wnt signaling. AFE is then ventralized by applying Wnt, BMP, fibroblast growth factor (FGF) and retinoic acid (RA) signaling to obtain lung and airway progenitors. Finally, these are further differentiated into more mature epithelial cells types using Wnt, FGF, cAMP and glucocorticoid agonism. This protocol is conducted in defined conditions, it does not involve genetic manipulation of the cells and it results in cultures in which the majority of the cells express markers of various lung and airway epithelial cells, with a predominance of cells identifiable as functional type II alveolar epithelial cells.

Monitoring changes in thioredoxin and over-oxidised peroxiredoxin in response to exercise in humans

INTRODUCTION

Peroxiredoxin (PRDX) and thioredoxin (TRX) are antioxidant proteins that control cellular signalling and redox balance, although their response to exercise is unknown. This study aimed to assess key aspects of the PRDX-TRX redox cycle in response to three different modes of exercise.

METHODS

Healthy males (n = 10, mean ± SD: 22 ± 3 yrs) undertook three exercise trials on separate days: two steady-state cycling trials at moderate (60% [Formula: see text]O2MAX; 27 min, MOD) and high (80% [Formula: see text]O2MAX; 20 min, HIGH) intensities, and a low-volume high-intensity interval training trial (10 × 1 min 90% [Formula: see text]O2MAX, LV-HIIT). Peripheral blood mononuclear cells were assessed for TRX-1 and over-oxidised PRDX (isoforms I-IV) protein expression before, during, and 30 min following exercise (post + 30). The activities of TRX reductase (TRX-R) and the nuclear factor kappa B (NF-κB) p65 subunit were also assessed.

RESULTS

TRX-1 increased during exercise in all trials (MOD, + 84.5%; HIGH, + 64.1%; LV-HIIT, + 205.7%; p < 05), whereas over-oxidised PRDX increased during HIGH only (MOD, - 28.7%; HIGH, + 202.9%; LV-HIIT, - 22.7%; p < .05). TRX-R and NF-κB p65 activity increased during exercise in all trials, with the greatest response in TRX-R activity seen in HIGH (p < 0.05).

DISCUSSION

All trials stimulated a transient increase in TRX-1 protein expression during exercise. Only HIGH induced a transient over-oxidation of PRDX, alongside the greatest change in TRX-R activity. Future studies are needed to clarify the significance of heightened peroxide exposure during continuous high-intensity exercise and the mechanisms of PRDX-regulatory control.

Lotus leaf (Nelumbo nucifera) and its active constituents prevent inflammatory responses in macrophages via JNK/NF-κB signaling pathway

Inflammation is a serious health issue worldwide that induces many diseases, such as inflammatory bowel disease (IBD), sepsis, acute pancreatitis and lung injury. Thus, there is a great deal of interest in new methods of limiting inflammation. In this study, we investigated the leaves of Nelumbo nucifera Gaertn, an aquatic perennial plant cultivated in eastern Asia and India, in anti-inflammatory pharmacological effects in the murine macrophage cell line RAW264.7. Results showed that lipopolysaccharide (LPS) increased the protein expression of inducible nitric oxide synthase (iNOS) and COX-2, as well as the mRNA expression and level of IL-6 and TNF-α, while NNE significantly reduced these effects of LPS. LPS also induced phospho-JNK protein expression. The JNK-specific inhibitor SP600125 decreased the proteins expression of phospho-JNK, iNOS, COX-2, and the mRNAs expression and levels of IL-6 and TNF-α. Further, NNE reduced the protein expression of phospho-JNK. LPS was also found to promote the translocation of NF-κB from the cytosol to the nucleus and to decrease the expression of cytosolic IκB. NNE and SP600125 treatment recovered the LPS-induced expression of NF-κB and IκB. While phospho-ERK and phospho-p38 induced by LPS, could not be reversed by NNE. To further investigate the major components of NNE in anti-inflammatory effects, we determined the quercetin and catechin in inflammatory signals. Results showed that quercetin and catechin significantly decreased the proteins expression of iNOS, COX-2 and phospho-JNK. Besides, the mRNAs and levels of IL-6 and TNF-α also decreased by quercetin and catechin treatment in LPS-induced RAW264.7 cells. These results showed that NNE and its major components quercetin and catechin exhibit anti-inflammatory activities by inhibiting the JNK- and NF-κB-regulated pathways and could therefore be an useful anti-inflammatory agent.

Coordination of insulin and Notch pathway activities by microRNA miR-305 mediates adaptive homeostasis in the intestinal stem cells of the Drosophila gut

Homeostasis of the intestine is maintained by dynamic regulation of a pool of intestinal stem cells. The balance between stem cell self-renewal and differentiation is regulated by the Notch and insulin signaling pathways. Foronda et al. show that miR-305 regulates the Notch and insulin pathways in the intestinal stem cells. miR-305 expression in the stem cells is under nutritional control via the insulin pathway.

Homeostasis of the intestine is maintained by dynamic regulation of a pool of intestinal stem cells. The balance between stem cell self-renewal and differentiation is regulated by the Notch and insulin signaling pathways. Dependence on the insulin pathway places the stem cell pool under nutritional control, allowing gut homeostasis to adapt to environmental conditions. Here we present evidence that miR-305 is required for adaptive homeostasis of the gut. miR-305 regulates the Notch and insulin pathways in the intestinal stem cells. Notably, miR-305 expression in the stem cells is itself under nutritional control via the insulin pathway. This link places regulation of Notch pathway activity under nutritional control. These findings provide a mechanism through which the insulin pathway controls the balance between stem cell self-renewal and differentiation that is required for adaptive homeostasis in the gut in response to changing environmental conditions.

Chloroacetic acid triggers apoptosis in neuronal cells via a reactive oxygen species-induced endoplasmic reticulum stress signaling pathway

Chloroacetic acid (CA), a chlorinated analog of acetic acid and an environmental toxin that is more toxic than acetic, dichloroacetic, or trichloroacetic acids, is widely used in chemical industries. Furthermore, CA has been found to be the major disinfection by-products (DBPs) of drinking water. CA has been reported to be highly corrosive and to induce severe tissue injuries (including nervous system) that lead to death in mammals. However, the effects and underlying mechanisms of CA-induced neurotoxicity remain unknown. In the present study, we found that CA (0.5-2.0 mM) significantly increased LDH release, decreased the number of viable cells (cytotoxicity) and induced apoptotic events (including: increases in the numbers of apoptotic cells, the membrane externalization of phosphatidylserine (PS), and caspase-3/-7 activity) in Neuro-2a cells. CA (1.5 mM; the approximate to LD50) also triggered ER stress, which was identified by monitoring several key molecules that are involved in the unfolded protein responses (including the increase in the expressions of p-PERK, p-IRE-1, p-eIF2α, ATF-4, ATF-6, CHOP, XBP-1, GRP 78, GRP 94, and caspase-12) and calpain activity. Transfection of GRP 78- and GRP 94-specific si-RNA effectively abrogated CA-induced cytotoxicity, caspase-3/-7 and caspase-12 activity, and GRP 78 and GRP 94 expression in Neuro-2a cells. Additionally, pretreatment with 2.5 mM N-acetylcysteine (NAC; a glutathione (GSH) precursor) dramatically suppressed the increase in lipid peroxidation, cytotoxicity, apoptotic events, calpain and caspase-12 activity, and ER stress-related molecules in CA-exposed cells. Taken together, these results suggest that the higher concentration of CA exerts its cytotoxic effects in neuronal cells by triggering apoptosis via a ROS-induced ER stress signaling pathway.

Downregulated miR329 and miR410 promote the proliferation and invasion of oral squamous cell carcinoma by targeting Wnt-7b

microRNA (miRNA) dysregulation contributes widely to human cancer but has not been fully assessed in oral cancers. In this study, we conducted a global microarray analysis of miRNA expression in 40 pairs of betel quid-associated oral squamous cell carcinoma (OSCC) specimens and their matched nontumorous epithelial counterparts. Eighty-four miRNAs were differentially expressed in the OSCC specimens compared with the matched tissue. Among these downregulated miRNAs, 19 miRNAs were found and mapped to the chromosome 14q32.2 miRNA cluster region, which resides within a parentally imprinted region designated as Dlk-Dio3 and known to be important in development and growth. Bioinformatic analysis predicted two miRNAs from the cluster region, miR329 and miR410, which could potentially target Wnt-7b, an activator of the Wnt-β-catenin pathway, thereby attenuating the Wnt-β-catenin signaling pathway in OSCC. Stable ectopic expression of Wnt-7b in OSCC cells overexpressing miR329 or miR410 restored proliferation and invasion capabilities abolished by these miRNA. Combining a demethylation agent and a histone deacetylase inhibitor was sufficient to reexpress miR329, miR410, and Meg3, consistent with epigenetic regulation of these miRNA in human OSCC. Specifically, arecoline, a major betel nut alkaloid, reduced miR329, miR410, and Meg3 gene expression. Overall, our results provide novel molecular insights into how betel quid contributes to oral carcinogenesis through epigenetic silencing of tumor-suppressor miRNA that targets Wnt-β-catenin signaling.