The determination of the molecular mechanism underlying retinal pathogenesis and visual dysfunction during innate inflammation, and the treatment effect of rapamycin thereon.
The endotoxin-induced ...uveitis and retinitis mouse model was established by injecting lipopolysaccharide. The mice were subsequently treated with rapamycin, a mammalian target of rapamycin (mTOR) inhibitor. The rhodopsin mRNA and protein expression level in the retina and the photoreceptor outer segment (OS) length in immunohistochemical stainings were measured, and visual function was recorded by electroretinography. Inflammatory cytokines, their related molecules, mTOR, and LC3 levels were measured by real-time PCR and/or immunoblotting. Leukocyte adhesion during inflammation was analyzed using concanavalin A lectin.
The post-transcriptional reduction in the visual pigment of rod photoreceptor cells, rhodopsin, OS shortening, and rod photoreceptor cell dysfunction during inflammation were suppressed by rapamycin. Activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and induction of inflammatory cytokines, such as interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1), and the activation of the downstream signaling protein, signal transducer and activator of transcription 3 (STAT3), which reduces rhodopsin in the retina during inflammation, were attenuated by rapamycin. Increased leukocyte adhesion was also attenuated by rapamycin. Interestingly, although mTOR activation was observed after NF-κB activation, mTOR inhibition suppressed NF-κB activation at the early phase, indicating that the basal level of activated mTOR was sufficient to activate NF-κB in the retina. In addition, the inhibition of NF-κB suppressed mTOR activation, suggesting a positive feedback loop of mTOR and NF-κB during inflammation. The ratio of LC3II to LC3I, which reflects autophagy induction, was not changed by inflammation but was increased by rapamycin.
Our results propose the potential use of rapamycin as a neuroprotective therapy to suppress local activated mTOR levels, related inflammatory molecules, and the subsequent visual dysfunction during retinal inflammation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Cancer cells undergo epithelial-mesenchymal transition (EMT) during invasion and metastasis. Although transforming growth factor-β (TGF-β) and pro-inflammatory cytokines have been implicated in EMT, ...the underlying molecular mechanisms remain to be elucidated. Here, we studied the effects of proinflammatory cytokines derived from the mouse macrophage cell line RAW 264.7 on TGF-β-induced EMT in A549 lung cancer cells. Co-culture and treatment with conditioned medium of RAW 264.7 cells enhanced a subset of TGF-β-induced EMT phenotypes in A549 cells, including changes in cell morphology and induction of mesenchymal marker expression. These effects were increased by the treatment of RAW 264.7 cells with lipopolysaccharide, which also induced the expression of various proinflammatory cytokines, including TNF-α and IL-1β. The effects of conditioned medium of RAW 264.7 cells were partially inhibited by a TNF-α neutralizing antibody. Dehydroxy methyl epoxyquinomicin, a selective inhibitor of NFκB, partially inhibited the enhancement of fibronectin expression by TGF-β, TNF-α, and IL-1β, but not of N-cadherin expression. Effects of other pharmacological inhibitors also suggested complex regulatory mechanisms of the TGF-β-induced EMT phenotype by TNF-α stimulation. These findings provide direct evidence of the effects of RAW 264.7-derived TNF-α on TGF-β-induced EMT in A549 cells, which is transduced in part by NFκB signalling.
The focus of the present study was whether and how infiltrating macrophages play a role in angiogenesis and the growth of cancer cells in response to the inflammatory cytokine interleukin (IL)‐1β. ...Lewis lung carcinoma cells overexpressing IL‐1β grew faster and induced greater neovascularization than a low IL‐1β‐expressing counterpart in vivo. When macrophages were depleted using clodronate liposomes, both neovascularization and tumor growth were reduced in the IL‐1β‐expressing tumors. Co‐cultivation of IL‐1β‐expressing cancer cells with macrophages synergistically augmented neovascularization and the migration of vascular endothelial cells. In these co‐cultures, production of the angiogenic factors vascular endothelial growth factor‐A and IL‐8, monocyte chemoattractant protein‐1, and matrix metalloproteinase‐9 were increased markedly. The production of these factors, induced by IL‐1β‐stimulated lung cancer cells, was blocked by a nuclear factor (NF)‐κB inhibitor, and also by the knockdown of p65 (NF‐κB) and c‐Jun using small interference RNA, suggesting involvement of the transcription factors NF‐κB and AP‐1. These results demonstrated that macrophages recruited into tumors by monocyte chemoattractant protein‐1 and other chemokines could play a critical role in promoting tumor growth and angiogenesis, through interactions with cancer cells mediated by inflammatory stimuli. (Cancer Sci 2007; 98: 2009–2018)
Spread of drug-resistant bacteria is a serious problem worldwide. We thus designed a new sequence-based protocol that can quickly identify bacterial compositions of clinical samples and their ...drug-resistance profiles simultaneously. Here we utilized propidium monoazide (PMA) that prohibits DNA amplifications from dead bacteria, and subjected the original and antibiotics-treated samples to 16S rRNA metagenome sequencing. We tested our protocol on bacterial mixtures, and observed that sequencing reads derived from drug-resistant bacteria were significantly increased compared with those from drug-sensitive bacteria when samples were treated by antibiotics. Our protocol is scalable and will be useful for quickly profiling drug-resistant bacteria.
1,2-Naphthoquinone (2-NQ) is a nucleophile acceptor that non-selectively makes covalent bonds with cysteine residues in various cellular proteins, and is also found in diesel exhaust, an air ...pollutant. This molecule has rarely been considered as a pharmacophore of bioactive compounds, in contrast to 1,4-naphthoquinone. We herein designed and synthesized a compound named N-(7,8-dioxo-7,8-dihydronaphthalen-1-yl)-2-methoxybenzamide (MBNQ), in which 2-NQ was hybridized with the nuclear factor-κB (NF-κB) inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) as a nucleophile acceptor. Although 50 µM MBNQ did not inhibit NF-κB signaling, 10 µM MBNQ induced cell death in the lung cancer cell line A549, which was insensitive to 2-NQ (10 µM). In contrast, MBNQ was less toxic in normal lung cells than 2-NQ. A mechanistic study showed that MBNQ mainly induced apoptosis, presumably via the activation of p38 mitogen-activated protein kinase (MAPK). Collectively, the present results demonstrate that the introduction of an appropriate substituent into 2-NQ constitutes a new biologically active entity, which will lead to the development of 2-NQ-based drugs.
Various outcomes of mortality, medical costs, and antimicrobial usage result from antimicrobial stewardship (AS) programmes. Here, we clarified the effects of AS implementation by a well-trained ...pharmacist in an open intensive care unit (open ICU) through a retrospective, comparative study of 5123 open ICU patients of Tokai University Hospital. The 12 months before and after AS implementation were considered the control and study periods, respectively. After AS implementation, the number of AS cases increased significantly. The period until the implementation of therapeutic drug monitoring was significantly shortened, and antimicrobial drug usage increased significantly. The methicillin-resistant Staphylococcus aureus (MRSA) detection rate decreased significantly. Earlier and more frequent AS implementation could enhance treatment effects, possibly decreasing the MRSA incidence. Despite active AS implementation, antimicrobial drug usage did not necessarily decrease. ICU pharmacists with experience in AS should take on leadership roles and implement active AS strategies in open ICU settings.
There have been great advances in the therapy of cancer and leukemia. However, there are still many neoplastic diseases that are difficult to treat. For example, it is often difficult to find ...effective therapies for aggressive cancer and leukemia. An NF-B inhibitor named dehydroxymethylepoxyquinomicin
(DHMEQ) was discovered in 2000. This compound was designed based on the structure of epoxyquinomicin isolated from a microorganism. It was shown to be a specific inhibitor that directly binds to and inactivates NF-B components. Until now, DHMEQ has been used by many scientists in the world
to suppress animal models of cancer and inflammation. Especially, it was shown to suppress difficult cancer models, such as hormone-insensitive breast cancer and prostate cancer, cholangiocarcinoma, and multiple myeloma. No toxicity has been reported so far. DHMEQ was administered via the
intraperitoneal (IP) route in most of the animal experiments because of its simplicity. In the course of developmental studies, it was found that IP administration never increased the blood concentration of DHMEQ because of the instability of DHMEQ in the blood. It is suggested that inflammatory
cells in the peritoneal cavity would be important for cancer progression, and that IP administration, itself, is important for the effectiveness and safety of DHMEQ. In the present review, we describe mechanism of action, its in vivo anticancer activity, and future clinical use of DHMEQ IP
therapy.
► Glybenclamide is an orally active K-channel blocker widely used for type II diabetes. ► It was found to inhibit PDGF-mediated cellular invasion in ovarian carcinoma cells. ► Thus, K-channel ...activity is likely to be a new target of anti-metastasis agent.
It has been demonstrated that potassium channels (K+ channels) play significant roles in some malignant phenotypes. Here, we provide the first evidence that treatment with glybenclamide, an ATP-sensitive K+ channel blocker, inhibited cell migration in an ovarian clear cell carcinoma cell line, ES-2. Treatment with glybenclamide or knockdown by siRNA targeted against K+ channel subunits demonstrated the suppression of ovarian cancer cell invasion, which occurred via inhibition of PDGF-AA secretion. Therefore, our findings suggest that K+ channel blockers may be useful chemotherapeutic drugs for blocking the invasiveness of ovarian cancers.
•Simultaneous and multi-point measurement of dermal emission flux of ammonia was conducted for ten healthy young volunteers.•Ammonia emanating from human skin surface was non-invasively collected by ...Passive Flux Sampler and determined by Ion chromatography.•Using the measured emission fluxes at 13 positions and surface area of the volunteers, the whole body dermal emission rate of ammonia was estimated.•The dermal emission was found more significant odor source than the breath exhalation in indoor environment.
Ammonia is one of the members of odor gases and a possible source of odor in indoor environment. However, little has been known on the actual emission rate of ammonia from the human skin surface. Then, this study aimed to estimate the whole-body dermal emission rate of ammonia by simultaneous and multi-point measurement of emission fluxes of ammonia employing a passive flux sampler – ion chromatography system. Firstly, the emission fluxes of ammonia were non-invasively measured for ten volunteers at 13 sampling positions set in 13 anatomical regions classified by Kurazumi et al. The measured emission fluxes were then converted to partial emission rates using the surface body areas estimated by weights and heights of volunteers and partial rates of 13 body regions. Subsequent summation of the partial emission rates provided the whole body dermal emission rate of ammonia. The results ranged from 2.9 to 12mgh−1 with an average of 5.9±3.2mgh−1 per person for the ten healthy young volunteers. The values were much greater than those from human breath, and thus the dermal emission of ammonia was found more significant odor source than the breath exhalation in indoor environment.
Conophylline (CnP), a vinca alkaloid extracted from the leaves of the tropical plant Tabernaemontana divaricate, attenuates hepatic fibrosis in mice. We have previously shown that CnP inhibits ...non-alcoholic steatohepatitis (NASH) using a methionine-choline-deficient (MCD) diet-fed mouse model. However, little is known about the CnP mediated inhibition of hepatic steatosis in high-fat diet-induced non-alcoholic fatty liver disease (NAFLD) mouse models. CnP (0.5 and 1 μg/g/body weight) was co-administered along with a high-fat diet to male BALB/c mice. After nine weeks of administering the high-fat diet, hepatic steatosis, triglyceride, and hepatic fat metabolism-related markers were examined. Administration of a high-fat diet for 9 weeks was found to induce hepatic steatosis. CnP dose-dependently attenuated the high-fat diet-induced hepatic steatosis. The diet also attenuated hepatic peroxisome proliferator-activated receptor alpha (PPARA) mRNA levels. PPARA is known to be involved in β-oxidation. CnP upregulated the mRNA levels of hepatic PPARA and its target genes, such as carnitine palmitoyl transferase 1 (CPT1) and CPT2, in a dose-dependent manner in the liver. Furthermore, levels of hepatic β-hydroxybutyrate, which is a type of ketone body, were increased by CnP in a dose-dependent manner. Finally, CnP increased the expression of the autophagosomal marker LC3-II and decreased the expression of p62, which are known to be selectively degraded during autophagy. These results indicate that CnP inhibits hepatic steatosis through the stimulation of β-oxidation and autophagy in the liver. Therefore, CnP might prove to be a suitable therapeutic target for NAFLD.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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