scholarly journals Membranes and bile formation. Composition of several mammalian biles and their membrane-damaging properties

1979 ◽  
Vol 178 (1) ◽  
pp. 201-208 ◽  
Author(s):  
R Coleman ◽  
S Iqbal ◽  
P P Godfrey ◽  
D Billington
Keyword(s):  
Guinea Pig ◽  
Bile Salts ◽  
Cell Damage ◽  
Membrane Damage ◽  
Total Content ◽  
Hepatic Cell ◽  
Membrane Composition ◽  
Bile Formation ◽  
Composition And Structure ◽  
High Concentrations

The total content and profile of bile salts and phospholipids are reported for several mammalian biles. Rabbit and guinea-pig biles are characterized by high proportions of conjugated dihydroxy bile salts with respect to trihydroxy bile salts, but contain relatively little phospholipid. Both rabbit and guinea-pig biles exhibit little evidence of hepatic cell damage, even though they are able to cause membrane damage (as evidenced by lysis of human erythrocytes) at low (2–3 mM) concentrations of bile salts; this lytic behaviour is also a property of their predominant bile salts. Addition of phosphatidylcholine to the bile or bile salt is able to decrease the lytic behaviour. Perhaps the most significant observation is that these biles, and their predominant bile salts, are dramatically less lytic towards sheep erythrocytes, indicating that some factor(s) in membrane composition and structure may partly explain the resistance of membranes of the biliary tract to the presence of high concentrations of potentially membrane-damaging bile salts.

Effects of hypertonic solutions on bile formation

1963 ◽  
Vol 205 (5) ◽  
pp. 863-867 ◽  
Author(s):  
J. Chenderovitch ◽  
E. Phocas ◽  
M. Rautureau
Keyword(s):  
Guinea Pig ◽  
Bile Acids ◽  
Bile Salts ◽  
Jugular Vein ◽  
Osmotic Gradient ◽  
Bile Formation ◽  
Quantitative Formation ◽  
Hypertonic Solutions ◽  
Different Types

Modifications of flow and composition of bile have been studied in the guinea pig with ligated ureters after injection of hypertonic solutions of two nonmetabolizable substances, mannitol and xylose (1.66 m), into the jugular vein. A distinct and persistent decrease in biliary flow always occurs. Analysis of this anticholeresis showed a parallel decrease in the flow of water and electrolytes, while the flow of bilirubin and bile acids is not modified. There are, then, two different types of mechanisms in the formation of bile: the osmotic mechanisms which control the quantity of water and electrolytes; and the active secretory mechanisms, independent of the first, for specific substances such as bilirubin and bile salts. Ultrafiltration does not occur in quantitative formation of bile, but the bile/blood osmotic gradient plays an important role.

scholarly journals Exceptional Solvent Tolerance inYarrowia lipolyticaIs Enhanced by Sterols

2018 ◽  
Author(s):  
Caleb Walker ◽  
Seunghyun Ryu ◽  
Cong T. Trinh
Keyword(s):  
Cell Wall ◽  
Organic Solvents ◽  
Membrane Damage ◽  
Solvent Tolerance ◽  
Wall Structure ◽  
Membrane Composition ◽  
Adaptive Laboratory Evolution ◽  
Fuels And Chemicals ◽  
High Concentrations ◽  
Manufacturing Platform

AbstractMicrobial biocatalysis in organic solvents such as ionic liquids (ILs) is attractive for making fuels and chemicals from complex substrates including lignocellulosic biomass. However, low IL concentrations of 0.5-1.0 % (v/v) can drastically inhibit microbial activity. In this study, we engineered an exceptionally robust oleaginous yeastYarrowia lipolytica, YlCW001, by adaptive laboratory evolution (ALE). The mutant YlWC001 shows robust growth in up to 18% (v/v) 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]), which makes it the most IL-tolerant microorganism published to our knowledge. Remarkably, YlCW001 exhibits broad tolerance in most commonly used hydrophilic ILs beyond [EMIM][OAc]. Scanning electron microscopy revealed that ILs significantly damage cell wall and/or membrane of wildtypeY. lipolyticawith observed cavities, dents, and wrinkles while YlCW001 maintains healthy morphology even in high concentrations of ILs up to 18% (v/v). By performing comprehensive metabolomics, lipidomics, and transcriptomics to elucidate this unique phenotype, we discovered that both wildtypeY. lipolyticaand YlCW001 reconfigured membrane composition (e.g., glycerophospholipids and sterols) and cell wall structure (e.g., chitin) under IL-stressful environments. By probing the steroid pathway at transcriptomic, enzymatic, and metabolic levels, we validated that sterols (i.e., ergosterol) are a key component of the cell membrane that enablesY. lipolyticato resist IL-responsive membrane damage and hence tolerate high IL concentrations. This study provides a better understanding of exceptional robustness ofY. lipolyticathat can be potentially harnessed as a microbial manufacturing platform for production of fuels and chemicals in organic solvents.

Hair Cell Damage in the Inner Ear of the Guinea Pig Due to Noise in a Workshop

1987 ◽  
Vol 103 (5) ◽  
pp. 204-211 ◽  
Author(s):  
B. Erlandsson ◽  
H. Hakanson ◽  
A. Ivarsson ◽  
P. Nilsson ◽  
J. Wersall
Keyword(s):  
Guinea Pig ◽  
Hair Cell ◽  
Inner Ear ◽  
Cell Damage ◽  
Hair Cell Damage

Hepatic uptake of intact glutathione S-conjugate, inhibition by organic anions, and sinusoidal catabolism

1993 ◽  
Vol 265 (3) ◽  
pp. G547-G554
Author(s):  
C. A. Hinchman ◽  
A. T. Truong ◽  
N. Ballatori
Keyword(s):  
Guinea Pig ◽  
Rat Liver ◽  
Marked Decrease ◽  
Hepatic Uptake ◽  
Half Time ◽  
High Concentrations ◽  
Rat Livers ◽  
Dose Dependent ◽  
Uptake And Metabolism ◽  
Guinea Pig Liver

To identify potential mechanisms for hepatic removal of circulating glutathione (GSH) conjugates, uptake and metabolism of S-2,4-dinitrophenylglutathione (DNP-SG) were examined in isolated perfused livers from rat and guinea pig. Guinea pig livers perfused with 5 mumol of DNP-SG in a recirculating system (50 microM initial concn) rapidly cleared the conjugate from the perfusate (half time 3.7 min), whereas clearance was considerably slower in rat liver (half time 35 min). Disappearance of DNP-SG from the perfusate was accompanied by a simultaneous appearance of DNP-SG and its metabolites in bile. Addition of acivicin, an inhibitor of gamma-glutamyltransferase (gamma-GT), to the perfusate resulted in a marked decrease in DNP-SG clearance by guinea pig liver but had no effect in rat liver, suggesting that in the guinea pig this process is largely dependent on sinusoidal gamma-GT activity. However, even in the presence of acivicin, rat and guinea pig livers removed nearly one-half of the administered DNP-SG from the recirculating perfusate over 30 min. High concentrations of DNP-SG were found in bile (up to 3.7 mM), indicating that the liver is capable of transporting the intact conjugate from the circulation. When rat livers were perfused with higher concentrations of DNP-SG (100 and 250 microM), biliary excretion of DNP-SG increased dose dependently, with concentrations in bile reaching 10 mM at the higher dose. This was accompanied by a dose-dependent choleresis.(ABSTRACT TRUNCATED AT 250 WORDS)

Bile formation and hepatic plasma membrane composition in guinea-pigs and rats

1995 ◽  
Vol 111 (4) ◽  
pp. 523-531 ◽  
Author(s):  
France Guertin ◽  
Anne Loranger ◽  
Guy Lepage ◽  
Claude C. Roy ◽  
Ibrahim M. Yousef ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Guinea Pigs ◽  
Membrane Composition ◽  
Bile Formation

scholarly journals Effects of the cationic protein poly-L-arginine on airway epithelial cellsin vitro

2002 ◽  
Vol 11 (3) ◽  
pp. 141-148 ◽  
Author(s):  
Shahida Shahana ◽  
Caroline Kampf ◽  
Godfried M. Roomans
Keyword(s):  
Electron Microscopy ◽  
Epithelial Cells ◽  
Cell Membrane ◽  
Cell Damage ◽  
Membrane Damage ◽  
Light And Electron Microscopy ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Cationic Protein ◽  
Induced Apoptosis

Background: Allergic asthma is associated with an increased number of eosinophils in the airway wall. Eosinophils secrete cationic proteins, particularly major basic protein (MBP).Aim: To investigate the effect of synthetic cationic polypeptides such as poly-L-arginine, which can mimic the effect of MBP, on airway epithelial cells.Methods: Cultured airway epithelial cells were exposed to poly-L-arginine, and effects were determined by light and electron microscopy.Results: Poly-L-arginine induced apoptosis and necrosis. Transmission electron microscopy showed mitochondrial damage and changes in the nucleus. The tight junctions were damaged, as evidenced by penetration of lanthanum. Scanning electron microscopy showed a damaged cell membrane with many pores. Microanalysis showed a significant decrease in the cellular content of magnesium, phosphorus, sodium, potassium and chlorine, and an increase in calcium. Plakoglobin immunoreactivity in the cell membrane was decreased, indicating a decrease in the number of desmosomes.Conclusions: The results point to poly-L-arginine induced membrane damage, resulting in increased permeability, loss of cell-cell contacts and generalized cell damage.

Action of guinea pig C8 adn C9: determination of the component causing membrane damage

1970 ◽  
Vol 7 (10) ◽  
pp. 860 ◽  
Author(s):  
U. Hadding ◽  
D. Bitter-Suermann ◽  
W. König
Keyword(s):  
Guinea Pig ◽  
Membrane Damage

Toxic Effects of Chromium Acetate Hydroxide on Cells Cultivated In Vitro

2001 ◽  
Vol 29 (2) ◽  
pp. 163-177 ◽  
Author(s):  
Emil Rudolf ◽  
Jan Peychl ◽  
Miroslav Červinka
Keyword(s):  
Dna Analysis ◽  
Cell Damage ◽  
Toxic Waste ◽  
Toxic Effects ◽  
Waste Materials ◽  
In Vitro Tests ◽  
High Concentrations ◽  
Discrete Manner ◽  
Chromium Acetate

Many human activities, particularly industrial ones, result in an ever-growing production of toxic waste materials. The dynamics of the toxic effects of chromium acetate hydroxide, which is found in high concentrations in a waste sediment produced in the Czech Republic, were assessed by using a battery of in vitro tests carried out on two cell lines: L-929 (mouse fibroblasts) and Hep 2 (human laryngeal cells). Various markers of cell damage were assessed by phase-contrast, video and fluorescence microscopy, fluorometry, and DNA analysis. Chromium acetate hydroxide, over a concentration range of 1–0.02mol/l induced immediate cell death by fixation, whereas, at 0.002mol/l, the treated cells died in a much slower, more discrete manner. All the detected markers of cell damage, whether immediate or slow, clearly demonstrated that the cells died by necrosis. On the other hand, test concentration of 0.001mol/l appeared to constitute a threshold at which no pathological changes of Hep 2 cells were observed over 96 hours. We conclude that chromium acetate hydroxide has a high toxic potential in vitro, which should be considered when studying the toxicity of waste materials containing it.

scholarly journals Comparative analysis of morpho-physiological features of Triticum vulgare sprouts after exposure to metal nanoparticles

2018 ◽  
Vol 80 (3) ◽  
pp. 190-195 ◽  
Author(s):  
A. M. Korotkova ◽  
O. V. Kvan ◽  
L. A. Bykova ◽  
O. S. Kudryavtseva ◽  
T. S. Videneeva ◽  
...  
Keyword(s):  
Mineral Metabolism ◽  
Cell Damage ◽  
Central Place ◽  
Specific Response ◽  
Triticum Vulgare ◽  
Physiological Processes ◽  
Adaptive Capabilities ◽  
High Concentrations ◽  
Secondary Contamination ◽  
Physiological And Biochemical

In this article violation of the mineral metabolism of plants as a result of secondary contamination with heavy metals (HM), which at high concentrations have a toxic effect on a wide variety of physiological processes, occupies a central place in the problem of the resistance of plant organisms to unfavorable environmental factors. Nanoparticles based on iron, copper and nickel are of considerable interest. The study of the mechanisms of plant adaptation to structurally different nanometals (NM) from the position of changing a number of physiological and biochemical parameters is relevant for a more complete understanding of the adaptive capabilities of organisms in conditions of technogenic nanomaterials. Analysis of the content of photosynthetic pigments allowed the formation of consistent ideas about the selectivity of the effect of nanometals on the components of the pigment system of seedlings, depending both on the composition of the metal and on its concentration. The obtained results serve as additional evidence of the existence of selectivity in the activation of a particular reaction of the plant's antioxidant system, determined by the nature of the nanomaterial. However, a change in the level of ROS in the presence of Ni? and Cu? can be attributed to the non-specific response of plants, since similar changes are characteristic of a variety of stresses of plants and in most cases require further research. In this aspect the main "target" of the action of LF metals was the root system of plants, which determined the interest in identifying mechanisms of phytotoxicity with an emphasis on the study of cell damage in this part of plants.

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