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51.
Seung Ho Jung Arpit Saxena Kamaljeet Kaur Emma Fletcher Venkatesh Ponemone James M. Nottingham Joseph A. Sheppe Maria Petroni Jennifer Greene Kelly Graves Manjeshwar Shrinath Baliga Raja Fayad 《Cytokine》2013,61(2):459-468
Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders of the gastrointestinal tract that affect more than 3 million people worldwide, but the pathological etiology is still unknown. The overall purpose of our investigations was to elucidate the possibility of pathological causes of IBD, and therefore, we determined the difference of inflammatory cytokine profiles in adipose tissue macrophages (ATMs) and T lymphocytes (ATTs) obtained near active lesions of IBD; investigated whether the alteration in ATM activation induces genes involved in collagen formation; and evaluated the effects of fatty acid oxidation inhibitors on factors involved in inflammation and collagen production by ATMs in IBD. Adipose tissues (ATs) were collected near active lesions and also at the margin of resected segments of the bowel from IBD patients with ulcerative colitis (UC) and CD (n = 14/group). Normal appearing ATs from control subjects (n = 14) who had colon resection for adenocarcinoma were collected as far away from the cancer lesion as possible to rule out possible changes. Compared with inactive disease lesions, ATMs and ATTs from active lesions released more IL-6, IL-4 and IL-13. Treatments of cytokine IL-4 and/or IL-13 to ATMs reduced iNOS expression but increased Arg-I expression which were exacerbated when treated with T cell- and adipocyte-conditioned medium. However, fatty acid oxidation inhibitors prevented the effects of cytokines IL-4 and/or IL-13 on iNOS and Arg-I expressions. This study was the first to show the effect of IL-4 and IL-13 on collagen formation, through iNOS and Arg-I expressions, that was exacerbated in a condition that mimics in vivo condition of active lesions. Moreover, our study was the first to provide potential benefits of fatty acid oxidation inhibitors to ATMs on preventing collagen formation; thus, providing therapeutic implications for individuals with intestinal fibrosis and stricture lesions, although future study should be guaranteed to elucidate the underlying mechanisms. 相似文献
52.
Myoung Suk Choi Soojin Park Taewon Choi Gihyun Lee Kyoung-Keun Haam Moo-Chang Hong Byung-Il Min Hyunsu Bae 《Cytokine》2013,61(1):256-265
Asthma is a potentially life-threatening inflammatory disease of the lung characterized by the presence of large numbers of CD4+ T cells. These cells produce the Th2 and Th17 cytokines that are thought to orchestrate the inflammation associated with asthma. Bee venom (BV) has traditionally been used to relieve pain and to treat chronic inflammatory diseases. Recent reports have suggested that BV might be an effective treatment for allergic diseases. However, there are still unanswered questions related to the efficacy of BV therapy in treating asthma and its therapeutic mechanism. In this study, we evaluated whether BV could inhibit asthma and whether BV inhibition of asthma could be correlated with regulatory T cells (Treg) activity. We found that BV treatment increased Treg populations and suppressed the production of Th1, Th2 and Th17-related cytokines in an in vitro culture system, including IL2, IL4, and IL17. Interestingly, production of IL10, an anti-inflammatory cytokine secreted by Tregs, was significantly augmented by BV treatment. We next evaluated the effects of BV treatment on allergic asthma in an ovalbumin (OVA)-induced mouse model of allergic asthma. Cellular profiling of the bronchoalveolar lavage (BAL) and histopathologic analysis demonstrated that peribronchial and perivascular inflammatory cell infiltrates were significantly lowered following BV treatment. BV also ameliorated airway hyperresponsiveness, a hallmark symptom of asthma. In addition, IL4 and IL13 levels in the BAL fluid were decreased in the BV treated group. Surprisingly, the beneficial effects of BV treatment on asthma were eradicated following Treg depletion by anti-CD25 antibody injection, suggesting that the major therapeutic targets of BV were Tregs. These results indicate that BV efficiently diminishes bronchial inflammation in an OVA-induced allergic asthma murine model, and that this effect might correlate with Tregs, which play an important role in maintaining immune homeostasis and suppressing the function of other T cells to limit the immune response. These results also suggest that BV has potential therapeutic value for controlling allergic asthma responses. 相似文献
53.
Jin Sil Chung Seung Baek Lee Seon Ho Park Sung Tae Kang Ah Ram Na Tong-Shin Chang 《Free radical research》2013,47(8):729-737
Reactive oxygen species (ROS) steady-state levels are required for entry into the S phase of the cell cycle in normal cells, as well as in tumour cells. However, the contribution of mitochondrial ROS to normal cell proliferation has not been well investigated thus far. A previous report showed that Romo1 was responsible for the high ROS levels in tumour cells. Here, we show that endogenous ROS generated by Romo1 are indispensable for cell cycle transition from G1 to S phase in normal WI-38 human lung fibroblasts. The ROS level in these cells was down-regulated by Romo1 knockdown, resulting in cell cycle arrest in the G1 phase. This arrest was associated with an increase in the level of p27Kip1. These results demonstrate that mitochondrial ROS generated by Romo1 expression is required for normal cell proliferation and it is suggested that Romo1 plays an important role in redox signalling during normal cell proliferation. 相似文献
54.
Sangmoo Lee Jin Il Kim Jun Heo Ilseob Lee Sehee Park Min-Woong Hwang Joon-Yong Bae Mee Sook Park Hyoung Jin Park Man-Seong Park 《Journal of microbiology (Seoul, Korea)》2013,51(5):676-681
Herbal medicine has been used in the orient for thousands of years to treat large and small ailments, including microbial infections. Although there are treatments for influenza virus infection, there is no treatment for drug-resistant viruses. It is time that we explored and exploited the multi-component nature of herbal extracts as multi-drug combination therapies. Here, we present data on the anti-influenza virus effect of a medicinal mushroom, Phellinus igniarius. The P. igniarius water extract was effective against influenza A and B viruses, including 2009 pandemic H1N1, human H3N2, avian H9N2, and oseltamivir-resistant H1N1 viruses. Virological assays revealed that the extract may interfere with one or more early events in the influenza virus replication cycle, including viral attachment to the target cell. Therefore, our results provide new insights into the use of P. igniarius as an anti-influenza medicine. 相似文献
55.
Activated Sludge Model no. 1 (ASM1) was modified and applied to Simultaneous Nitrification and Denitrification (SND) in oxygen-limited MBR. In order to calibrate the model correctly, the parametric sensitivity was performed using AQUASIM 2.0 to find the most important coefficients. The most sensitive coefficients in the model of oxygen-limited MBR were related to the growth of heterotrophic biomass. While the total autotrophic biomass concentration (XBA) was decreased by decreasing DO concentration, there was an increase in the nitrite-oxidizing biomass concentration by a small amount. This model also showed that over 97% of permeate Soluble Chemical Oxygen Demand (SCOD) was the Soluble Inert (SI). The model showed the change in the ammonia-oxidizing and nitrite-oxidizing biomass was decreased by decreasing DO concentration. However, there was an increase in the nitrite-oxidizing biomass concentration by a small amount due to the biomass retained in the bioreactor with membrane. It is contradictory to the reported observations for conventional activated sludge process. 相似文献
56.
Seung Hyun Kim Sin-Duk Jang Ki Yong Lee Sang Hyun Sung 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):230-233
A methanolic extract of dried leaves of Polygala japonica Houtt (Polygalaceae) significantly attenuated nitric oxide production in lipopolysaccharide-simulated BV2 microglia. Five anthraquinones chrysophanol (1), emodin (2), aloe-emodin (3), emodin 8-O-β-D-glucopyranoside (4) and trihydroxy anthraquinone (5), and four flavonoids kaempferol (6), chrysoeriol (7), kaempferol 3-gentiobioside (8) and isorhamnetin (9) were isolated from the methanolic extract using bioactivity-guided fractionation. Among them, compounds 1–4, 6 and 7 showed significant inhibitory effect on lipopolysaccharide-induced nitric oxide production in BV2 microglia at the concentrations ranging from 1.0 to 100.0 μM. 相似文献
57.
Moon Woo Chun Sung Pil Choi Myong Jung Kim Chol Joon Bae Hyung Ryong Moon Hee-Doo Kim 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):615-616
Abstract Novel 1,3-oxathiolanyl pyrimidine nucleosides with 5-hydroxymethyl substituent were synthesized starting from d-mannose and evaluated for antiviral activities against HIV-1, HSV type 1,2 and HCMV. 相似文献
58.
Tam Dinh Le Vo Ji-seun Ko Seung Hwan Lee Si Jae Park Soon Ho Hong 《Biotechnology and Bioprocess Engineering》2013,18(6):1062-1066
This study investigated the effect of glutamate decarboxylase from Neurospora crassa OR74A on GABA production in Escherichia coli. GABA is one of the inhibitory neurotransmitters in the mammalian central nervous system, and can be used as a precursor of promising biopolymer Nylon 4. E. coli that overexpressed N. crassa glutamate decarboxylase was cultured at various pH levels and temperatures to determine optimum conditions for GABA production. When the recombinant E. coli strain was cultured at 30°C and pH 3, a final GABA concentration of 5.26 g/L was obtained from 10 g/L of monosodium glutamate (MSG), corresponding to a GABA yield of 86.23%. 相似文献
59.
Fires change the diversity and composition of insects in forest ecosystems. In the present study, we examined the change of butterfly communities after a fire including the increase of butterfly richness, grassland species, and generalist species, and more changed communities. Butterflies were surveyed for 5 years after the big Uljin fire in 2007. During each year, butterflies were counted monthly by the line transect method from April to October at two sites (burned vs. unburned, ~ 1.5 km routes). Specialist grassland species decreased in the year of the fire but generalist species did not increase significantly. Butterfly richness did not change but butterfly diversity decreased due to a sudden increase of a species, Polygonia c-aureum. The butterfly community in the year of the fire was different from those in later years, showing temporary change of community in the year of the fire. Species composition was significantly different between burned and unburned sites, but this phenomenon cannot be interpreted as an influence of fire due to highly variable species composition of local butterfly assemblages and the non-repetitive sampling site of the present study. 相似文献
60.
Bit Na Seo Jung Min Ryu Seung Pil Yun Ji Hoon Jeon Su Shin Park Keon Bong Oh Jin-Ki Park Ho Jae Han 《Apoptosis : an international journal on programmed cell death》2013,18(7):811-824
Delphinidin, gallic acid, betulinic acid, and ursolic acid, which are bio-active ingredients in a variety of fruits, vegetables, and herbs, have potent antioxidant activity and various biological activities. However, it is not clear whether these bio-active ingredients can significantly contribute to the protection of embryonic stem (ES) cells from hypoxia-induced apoptosis. In the present study, hypoxia-induced ES cells apoptosis with time, which were abrogated by pretreatment with all ingredients. Hypoxia-induced ROS generation was blocked by pretreatment with all ingredients in a dose-dependent manner, with the maximum ROS scavenging effect observed for delphinidin. Hypoxia increased phosphorylation of JNK and NF-κB were blocked by pretreatment of delphinidin as well as NAC. Hypoxia decreased phosphorylation of Aktthr308 and ser473; these decreases were reversed by pretreatment with delphinidin or NAC. However, Akt inhibition did not affect NF-κB phosphorylation. Delphinidin attenuated the hypoxia-induced increase in Bax, cleaved caspase-9, cleaved caspase-3, and decrease in Bcl-2, which were diminished by pretreatment of Akt inhibitor. Hypoxia induced Bax translocation from the cytosol to mitochondria. Furthermore, hypoxia induced mitochondria membrane potential loss and cytochrome c release in cytosol, which were blocked by delphinidin pretreatment. Hypoxia induced cleavage of procaspase-9 and procaspase-3 which were blocked by delphinidin or SP600125, but Akt inhibitor abolished the protection effect of delphinidin. Moreover, inhibition of JNK and NF-κB abolished hypoxia-induced ES cell apoptosis and inhibition of Akt attenuated delphinidin-induced blockage of apoptosis. The results indicate that delphinidin can prevent hypoxia-induced apoptosis of ES cells through the inhibition of JNK and NF-κB phosphorylation, and restoration of Akt phosphorylation. 相似文献