scholarly journals Biologically active pigment and ShlA cytolysin of Serratia marcescens induce autophagy in a human ocular surface cell line

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Kimberly M. Brothers ◽  
Nicholas A. Stella ◽  
Robert M. Q. Shanks
Keyword(s):  
Serratia Marcescens ◽  
Cell Line ◽  
Ocular Surface ◽  
Biologically Active ◽  
Surface Cell

scholarly journals Differential susceptibility of airway and ocular surface cell lines to FlhDC-mediated virulence factors PhlA and ShlA from Serratia marcescens

2020 ◽  
Author(s):  
Nicholas A. Stella ◽  
Kimberly M. Brothers ◽  
Robert M. Q. Shanks
Keyword(s):  
Epithelial Cells ◽  
Serratia Marcescens ◽  
Cell Lines ◽  
Ocular Surface ◽  
Type Species ◽  
Wild Type ◽  
Bacterial Killing ◽  
Content Type ◽  
Link Type ◽  
Surface Cell

Introduction. Serratia marcescens is a bacterial pathogen that causes ventilator-associated pneumonia and ocular infections. The FlhD and FlhC proteins complex to form a heteromeric transcription factor whose regulon, in S. marcescens , regulates genes for the production of flagellum, phospholipase A and the cytolysin ShlA. The previously identified mutation, scrp-31, resulted in highly elevated expression of the flhDC operon. The scrp-31 mutant was observed to be more cytotoxic to human airway and ocular surface epithelial cells than the wild-type bacteria and the present study sought to identify the mechanism underlying the increased cytotoxicity phenotype. Hypothesis/Gap Statement. Although FlhC and FlhD have been implicated as virulence determinants, the mechanisms by which these proteins regulate bacterial cytotoxicity to different cell types remains unclear. Aim. This study aimed to evaluate the mechanisms of FlhDC-mediated cytotoxicity to human epithelial cells by S. marcescens . Methodology. Wild-type and mutant bacteria and bacterial secretomes were used to challenge airway and ocular surface cell lines as evaluated by resazurin and calcein AM staining. Pathogenesis was further tested using a Galleria mellonella infection model. Results. The increased cytotoxicity of scrp-31 bacteria and secretomes to both cell lines was eliminated by mutation of flhD and shlA. Mutation of the flagellin gene had no impact on cytotoxicity under any tested condition. Elimination of the phospholipase gene, phlA, had no effect on bacteria-induced cytotoxicity to either cell line, but reduced cytotoxicity caused by secretomes to airway epithelial cells. Mutation of flhD and shlA, but not phlA, reduced bacterial killing of G. mellonella larvae. Conclusion. This study indicates that the S. marcescens FlhDC-regulated secreted proteins PhlA and ShlA, but not flagellin, are cytotoxic to airway and ocular surface cells and demonstrates differences in human epithelial cell susceptibility to PhlA.

scholarly journals Bacteria induce autophagy in a human ocular surface cell line

2018 ◽  
Vol 168 ◽  
pp. 12-18 ◽  
Author(s):  
Kimberly M. Brothers ◽  
Regis P. Kowalski ◽  
Shenghe Tian ◽  
Paul R. Kinchington ◽  
Robert M.Q. Shanks
Keyword(s):  
Cell Line ◽  
Ocular Surface ◽  
Surface Cell

Ecological and physiological as well as biochemical properties of representatives of the Genus sedum L.

2014 ◽  
Vol 25 (3-4) ◽  
pp. 24-33
Author(s):  
O. I. Dzjuba ◽  
M. V. Yatsenko
Keyword(s):  
Nitric Oxide ◽  
Cell Line ◽  
Methanol Extract ◽  
Hepatoma Cell ◽  
Ethanol Extract ◽  
Biochemical Properties ◽  
Biologically Active ◽  
Hepatoma Cell Line ◽  
Dependent Manner ◽  
Dose Dependent

The article deals with the history of the study and the current state of research of physiological and biochemical properties of the plant genus Sedum that are useful for human and has been used in folk medicine for many years. It was noticed that antioxidant properties of extracts from plants S. sarmentosum, S. sempervivoides, S. takesimense were caused by the presence of phenolic compounds. Methanol extract of plants S. takesimense exhibited strong scavenging activities against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radicals as well as significant inhibitory effects on lipid peroxidation and low density lipoprotein (LDL) oxidation induced by a metal ion Cu2+. Various immunomodulatory activities of various fractions of plants extracts (S. dendroideum, S. kamtschaticum, S. sarmentosum, S. telephium) are observed. It was shown that the ethanol extract of S. sarmentosum and it’s fractions suppressed specific antibody and cellular responses to ovalbumin in mice. The methanol extract of plants S. sarmentosum reduced the levels of anti-inflammatory markers, such as volume of exudates, number of polymorphonuclear leukocytes, suppressed nitric oxide synthesis in activated macrophages via suppressed induction of inducible nitric oxide synthase (iNOS). Polysaccharides fractions from plants S. telephium inducing productions of tumor necrosis factor alpha (TNF-α), increasing the intensity of phagocytosis in vitro and in vivo. Methanol extract from the whole part of S. kamtschaticum strongly inhibit PGE2 production from lipopolysaccharide-induced RAW 264.7 cells, a mouse macrophage cell line via modulating activity in gene expression of the enzyme cyclooxygenase-2 (COX-2). The methanol extract of plants S. sarmentosum and the major kaempferol glycosides from S. dendroideum have antinociceptive activity. It was noticed that anti-adipogenic activity of extracts from plants S. kamtschaticum were caused by inhibition of peroxisome-proliferator-activated receptor γ (PPARγ) expression and it’s dependent target genes, such as genes encoding adipocyte protein 2 (аР2), lipoprotein lipase (LPL), adiponectin and CD36. Polysaccharides fractions from S. telephium cause inhibition of cell adhesion of human fibroblast (MRC5) to laminin and fibronectin via interfere with integrin-mediated cell behaviour and they contributed to the role of polysaccharides in cell-matrix interaction. The methanol extract of plants S. sarmentosum exhibited a significant inhibitory activity in the chick embryo chorioallantoic membrane angiogenesis in a dose-dependent manner. The crude alkaloid fraction of S. sarmentosum caused a dose-dependent inhibition of cell proliferation on murine hepatoma cell line BNL CL.2 and human hepatoma cell line HepG2 without necrosis or apoptosis. Alkaloids from plants S. sarmentosum may improve survival of hepatoma patients via the inhibition of excessive growth of tumor cells. Plant’s juices have antiviral activity (S. sarmentosum, S. spurium, S. stahlii). Crude ethanol extract S. praealtum have spermicidal activity of the in mice and a relevant inhibitory effect of aqueous extract on human spermatozoa motility as well as an anti-fertilizing activity in rats. Hepatoprotective triterpenes, e.g., δ-amyrone, 3-epi-δ-amyrin, δ-amyrin and sarmentolin were isolated from S. sarmentosum. 2- and 2,6-substituted piperidine alkaloids (e.g., norsedamine, allosedridine, sedamine, allosedamine) are observed in plants S. acre, which in the presence of data on the use of pyridine and piperidine derivatives for treating neurodegenerative diseases (e.g., Alzheimer's disease), points on the promising research in this area. Taking into account that biologically active compounds are accumulated in the aboveground vegetative organs of plants of Sedum, the prospects of further study of the use of Sedum for the purposes of biotechnology and in the pharmaceutical industry becomes apparent. This work extends the existing views regarding the use of plants Sedum.

scholarly journals Chemical compositions, antimicrobial effects, and cytotoxicity of Asia minor wormwood (Artemisia splendens Willd.) growing in Iran

BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Fariba Heshmati Afshar ◽  
Masumeh Zadehkamand ◽  
Zahra Rezaei ◽  
Abbas Delazar ◽  
Vahideh Tarhriz ◽  
...  
Keyword(s):  
Cell Line ◽  
Proliferative Activity ◽  
Methanolic Extract ◽  
Biologically Active ◽  
Flavonoid Glycosides ◽  
Control Group ◽  
Chemical Compositions ◽  
Preparative Hplc ◽  
Cytotoxicity Activity ◽  
Methanolic Extracts

Abstract Background Artemisia splendens from the Asteraceae family is a new source of biologically active compounds. The current study investigated to evaluate antimicrobial and cytotoxicity activity of methanolic extracts and their fractions obtained from aerial parts by agar disk diffusion and MTT methods, respectively. The active fractions were subjected to preparative HPLC for isolating the pure compounds, which were structurally elucidated, by 1H and 13C NMR. Results The results showed that the methanolic extract and its 60% SPE fraction have the anti-proliferative activity on A549 cell line in comparison with the control group. Meanwhile, the methanolic extract and its 40% SPE fraction can inhibit the growth of Gram-positive strains as anti-microbial activity. The 60% SPE fraction also illustrated anti-proliferative activity on the HT-29 cell line compared to the control group. Chromatographic separations via preparative HPLC yielded 5 flavonoids and three flavonoid glycosides. Conclusion Based on the results it can be concluded that A. splendens as a potential source of cytotoxic and antimicrobial compounds can be used in pharmaceutics.

CHEMICAL AND BIOLOGICAL ANALYSIS OF THE BIOCTIVE FRACTIONS OF THE LEAVES OF SCAEVOLA TACCADA (GAERTN.) ROXB

2021 ◽  
pp. 35-41
Author(s):  
EMAN M. ABDEL GHANI ◽  
ABEER M. EL SAYED ◽  
SOAD H. TADROS ◽  
FATHY M. SOLIMAN
Keyword(s):  
Ethyl Acetate ◽  
Petroleum Ether ◽  
Cell Line ◽  
Carcinoma Cell ◽  
Antioxidant Effect ◽  
Carcinoma Cell Line ◽  
Biologically Active ◽  
Breast Carcinoma Cell Line ◽  
Gram Positive ◽  
Butanol Fraction

Objective: Scaevola taccada. (Gaertn.) Roxb. is widely dispersed all along the coasts of Africa. It is used in folk medicine for diversity of ailments. This study aims to investigate the major phytoconstituents and biological activities of the leaves of S. taccada (Gaertn.) Roxb. Methods: In vitro biological examination viz. antimicrobial, cytotoxic and antioxidant activities of the ethanol extract of the leaves (EE) and its fractions; (petroleum ether (PE), methylene chloride (MC), ethyl acetate (EA) and n-butanol(BuOH)) were carried out. Estimation of the phytochemicals of biologically active fractions was done. Results: n-butanol fraction displayed remarkable antimycobacterium activity. Petroleum ether as well as n-butanol fractions evidenced a cytotoxic effect on breast carcinoma cell line (MCF7) and colon carcinoma cell line (HCT) with IC50 11.7 and 15.04 µg/ml respectively. Moreover, ethyl acetate fraction exhibits an antioxidant effect with EC50 476.7±0.57 µg/ml. n-tetradecane 1, α-amyrin palmitate 2, α-amyrin acetate 3, α-amyrin 4, stigmasterol 5, luteolin-7-O-β-glucoside 6, rutin 7 and alidyjosioside 8 were identified in S. taccada (Gaertn.) Roxb. leaves. Conclusion: Petroleum ether fraction is a cytotoxic candidate, especially against (MCF-7). It exhibited a moderate antifungal and antibacterial against certain Gram-positive bacteria. Ethyl acetate showed an antioxidant effect along with moderate antifungal activity. n-butanol fraction exerted potential antimycobacterial, significant cytotoxic activity against (HCT), good antifungal and antibacterial against Gram-positive and Gram-negative bacteria. Stigmasterol, luteolin-7-O-β-glucoside, rutin and alidyjosioside were isolated for the first time from S. taccada (Gaertn.) Roxb. Leaves.

Studies on the use of cultured cells in a bioassay for parathyroid hormone

1994 ◽  
Vol 143 (2) ◽  
pp. 261-268
Author(s):  
A E Armston ◽  
P J Wood
Keyword(s):  
Parathyroid Hormone ◽  
Cyclic Amp ◽  
Cell Line ◽  
Cultured Cells ◽  
Biologically Active ◽  
Kidney Cell Line ◽  
Opossum Kidney ◽  
Pre Treatment ◽  
Set Up ◽  
Insufficient Sensitivity

Abstract Measurement of parathyroid hormone (PTH) is important for diagnosing hyper- and hypoparathyroidism. The move to two-site immunometric assays that detect the whole molecule has improved the discrimination of these conditions but these assays may be too restrictive because some PTH fragments that are biologically active may not be detected. In addition, PTH-like peptide of malignancy, an important cause of malignancy-associated hypercalcaemia, is not detected by the two-site assays. Experiments were performed to set up a simple, robust and inexpensive bioassay for PTH, exploiting a kidney cell line and using cyclic AMP or an eluted stain assay as the end point. Of the 12 cell lines tested, an opossum kidney (WOK) cell line showed the most promise. Despite optimization of the procedure to include pre-treatment with dexamethasone, insulin and PTH, followed by incubation in the presence of 5′ -guanylimidodiphosphate, isobutyl-1-methylxanthine and forskolin, the WOK cells showed insufficient sensitivity for use in a cultured cell bioassay for PTH in human serum. In addition, the cells were less sensitive to PTH-like peptide precluding their use for an assay for this molecule. Journal of Endocrinology (1994) 143, 261–268

scholarly journals Regulation of erythropoietin production in a human hepatoblastoma cell line

Blood ◽  
1987 ◽  
Vol 70 (6) ◽  
pp. 1904-1909
Author(s):  
OJ Nielsen ◽  
SJ Schuster ◽  
R Kaufman ◽  
AJ Erslev ◽  
J Caro
Keyword(s):  
Cell Line ◽  
Northern Blot ◽  
Proliferative Activity ◽  
Northern Blot Analysis ◽  
Cobalt Chloride ◽  
Biologically Active ◽  
Erythropoietin Production ◽  
Rna Probe ◽  
Hepatoblastoma Cell Line

Production of immuno and biologically active erythropoietin was documented to occur in the human hepatoblastoma cell line HepG-2. The expression of the erythropoietin gene was further verified by Northern blot analysis using a single stranded RNA probe. In vitro studies showed that erythropoietin production by these cells was not stimulated by hypoxia or cobalt chloride, but was related to the proliferative activity of the cells in culture. In addition it was found that the secretion of erythropoietin was almost completely abrogated by tunicamycin, an inhibitor of N-linked glycosylation. This effect of tunicamycin was also observed in a permanently transfected cell line that secretes erythropoietin in large quantities.

scholarly journals Modulation of CAT-2B-Mediated l-Arginine Uptake and Nitric Oxide Biosynthesis in HCT116 Cell Line Through Biological Activity of 4′-Geranyloxyferulic Acid Extract from Quinoa Seeds

2019 ◽  
Vol 20 (13) ◽  
pp. 3262
Author(s):  
Sara Franceschelli ◽  
Daniela Maria Pia Gatta ◽  
Mirko Pesce ◽  
Alessio Ferrone ◽  
José Luis Quiles ◽  
...  
Keyword(s):  
Cell Line ◽  
Cancer Progression ◽  
Hct116 Cell ◽  
Chenopodium Quinoa ◽  
Ethanol Extract ◽  
Biologically Active ◽  
Inflammatory Status ◽  
Arginine Uptake ◽  
Cellular Environment ◽  
Hct 116

Chenopodium quinoa Wild is a “pseudocereal” grain which attracts a lot of attention in the scientific community as it has a positive effect on health. Here, we investigate the presence of biologically active O-prenylated phenylpropanoids in the ethanol extract of commercially available quinoa seeds. We claim that 4′-Geranyloxyferulic acid (GOFA) was the only phytochemical product found that belongs to quinoa’s group secondary metabolites. We studied the changes in the oxidative and inflammatory status of the cellular environment in HCT 116 cell line processed with quinoa extract and its component GOFA; the implementation was done through the analysis of the antioxidant enzymes (SOD and CAT), the pro-inflammatory components (iNOS, IL-6 and TNF-α), and the products of intermediary metabolism (ONOO−, O2−). Moreover, the l-arginine uptake was proposed as a target of the tested compounds. We demonstrated that the GOFA, through a decrease of the CAT-2B expression, leads to a reduction of the l-arginine uptake, downregulating the harmful iNOS and restoring the altered redox state. These results propose a new molecular target involved in the reduction of the critical inflammatory process responsible for the cancer progression.

scholarly journals Are Compounds Membrane-Associated or Present in the Cytosol? A Study Using Polyphenols in a Colon Carcinoma Cell Line Model

2020 ◽  
Vol 6 (6) ◽  
pp. 451-456
Author(s):  
Hannah Deusser ◽  
Isabel Groh ◽  
Tamara Bakuradze ◽  
Nadine Simson ◽  
Eva Kaiser ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Cell Line ◽  
Colon Carcinoma ◽  
Carcinoma Cell ◽  
Carcinoma Cell Line ◽  
Biologically Active ◽  
Colon Carcinoma Cell Line ◽  
Cell Line Model ◽  
Apple Products

Abstract Purpose We investigated the cytosolic and membrane-associated contents of polyphenols after 4 hours of incubation (50 μM of each polyphenol) in the colon carcinoma cell line T84 using a novel, rapid, and convenient method based on permeabilization of the cell membrane using digitonin. The colon carcinoma cell line was used to investigate the intestinal uptake of polyphenols present in apple products. Recent Findings The results showed that hydroxycinnamic acids (caffeic and 5-caffeoylquinic acid) were only detected in the cytosolic fractions. In contrast, 0.3 to 8.2% of the initial concentrations (50 μM) of the flavonoids phloretin, quercetin, phloretin 2′-O-glucoside, and quercetin 3-O-rhamnoside were found in the membrane-associated fractions. In the cytosolic fractions, 0.2–2.9% of these compounds were detected, corresponding to 25 to 40% of the total cell-associated (cytosolic plus membrane-associated fractions) polyphenol content. Summary Our results showed that after uptake, polyphenols were present in the cytosolic fraction of the cells as well as associated with the cell membrane. The presented method provides a useful in vitro tool for determining biologically active compounds in cellular fractions.

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