Radiation Killing ofE. ColiK1060: Role of Membrane Fluidity, Hypothermia and Local Anaesthetics

Studies have shown that protein undernutrition (PU) modifies the membrane lipid composition in the intestine and liver, as well as in plasma and other areas. However, there is limited information on the effect of PU on synaptosomal membrane lipid composition and fluidity and the protective role of selenium (Se) and zinc (Zn), which is a major focus of the present study. For 10 weeks, rats were fed diets containing 16% casein, which constituted the adequate protein diet, or 5% casein, representing the PU diet. The animals were supplemented with Se and Zn at a concentration of 0.15 and 227 mg L-1, respectively, in drinking water for 3 weeks. The results showed a significant increase in total lipids, glycolipids, triglycerides, cholesterol, and the cholesterol/phospholipid (Chol/PL) ratio, and a significant reduction in phospholipids and membrane fluidity. Se and Zn supplementation to PU rats, however, significantly lowered total lipids, glycolipids, triglycerides, cholesterol, and the Chol/PL ratio, while phospholipids and membrane fluidity were significantly restored. It is concluded that a perturbed lipid composition induced by PU affects the membrane structure and fluidity, which in turn influences membrane functions. The study suggests that Se and Zn supplementation might be beneficial in restoring the lipid dyshomeostasis associated with PU.

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The role of endogenous Na+,K+-adenosine triphosphatase inhibitory factor in the regulation of membrane fluidity of erythrocytes in essential hypertension

Journal of Hypertension ◽

10.1097/00004872-199207000-00009 ◽

1992 ◽

Vol 10 (7) ◽

pp. 657???662 ◽

Cited By ~ 4

Author(s):

Kazushi Tsuda ◽

Hiroki Shima ◽

Jiro Takeda ◽

Keizo Kimura ◽

Ichiro Nishio ◽

...

Keyword(s):

Essential Hypertension ◽

Membrane Fluidity ◽

Adenosine Triphosphatase ◽

Inhibitory Factor

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P0981ANTIDIABETIC AND RENOPROTECTIVE ROLE OF METFORMIN ON METABOLIC PARAMETERS IN KIDNEY OF DIABETIC AGING RATS

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfaa142.p0981 ◽

2020 ◽

Vol 35 (Supplement_3) ◽

Author(s):

Pardeep Kumar ◽

Najma Baquer

Keyword(s):

Renal Function ◽

Antioxidant Enzymes ◽

Membrane Fluidity ◽

Renin Angiotensin System ◽

Glucose Transporters ◽

Dna Degradation ◽

Female Rats ◽

Aging Rats ◽

Age Related

Abstract Background and Aims The objective of this study was to investigate renoprotective effects of metformin on renal function, mitochondrial and antioxidant enzymes, oxidative stress biomarker, DNA degradation and expression of glucose transporters in of diabetic aging female rats. Method Young (3 months) adult (12 months) and aged (24 months) rats will be diabetic by using alloxan monohydrate. Metformin was administered i.p. at a dose of 200 mg/kg/day for 30 days to both control and diabetic aging rats. A detailed study was carried on membrane fluidity, lipofuscin, antioxidant enzymes and DNA degradation to identify the antidiabetic and antiaging role of metformin using biochemical ,molecular and histiochemical study. Renal function was assessed by measuring proteinuria, enzymuria, expression of glucose transporters, renin-angiotensin system, and activities of polyol pathway enzymes. Results Present study shows that there was a similar pattern of increased lipid peroxidation, lipofuscin, DNA degradation and glucose transporters expression with upregulation of renal angiotensin-converting enzyme and a decrease in membrane fluidity, glutamate dehydrogenase, Na+ K+ ATPse, antixodant enzymes activities in both aging and diabetes. Metformin treatment helped to reverse the age related changes studied, to normal levels, elucidating an anti-aging, antidiabetic and renoprotective action. Metformin effectively countered the diabetes-induced structural abnormalities of renal tissue of aging rats. Conclusion Metformin was found to be an effective treatment in stabilizing and normalizing the renal functions; therefore this therapy can be considered an alternative to be explored further as a means of diabetic and aged related disorders control. The results of this study will be useful for pharmacological modification of the aging process and applying new strategies for control of age related disorders including metabolic syndrome.

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pH-dependent fusion of didodecyl phosphate vesicles: role of hydrogen-bond formation and membrane fluidity

The Journal of Physical Chemistry ◽

10.1021/j100326a034 ◽

1988 ◽

Vol 92 (15) ◽

pp. 4416-4420 ◽

Cited By ~ 15

Author(s):

Leo A. M. Rupert ◽

Jan F. L. Van Breemen ◽

Dick Hoekstra ◽

Jan B. F. N. Engberts

Keyword(s):

Hydrogen Bond ◽

Membrane Fluidity ◽

Bond Formation ◽

Hydrogen Bond Formation ◽

Ph Dependent

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Tolerance of spermatozoa to hypotonic stress: role of membrane fluidity and correlation with cryosurvival

Reproduction Fertility and Development ◽

10.1071/rd13177 ◽

2015 ◽

Vol 27 (2) ◽

pp. 285 ◽

Cited By ~ 8

Author(s):

Harriëtte Oldenhof ◽

Anna Heutelbeck ◽

Anne-Kathrin Blässe ◽

Heinrich Bollwein ◽

Gunilla Martinsson ◽

...

Keyword(s):

Membrane Fluidity ◽

Sperm Motility ◽

Membrane Integrity ◽

Freeze Tolerance ◽

Individual Variability ◽

Temperature Range ◽

Hypotonic Stress ◽

Osmotic Tolerance ◽

Bovine Spermatozoa

The aim of this study was to evaluate inter-individual variability in osmotic properties of stallion spermatozoa and its correlation with cryosurvival. In addition, temperature dependency of hypo-osmotic tolerance and membrane fluidity were studied. Stallion sperm membranes exhibited good resistance towards hypotonic stress in the 15–30°C temperature range, whereas membrane stability was found to be decreased at 4 and 37°C. Bull spermatozoa showed greater hypo-osmotic tolerance compared with stallion spermatozoa, especially at temperatures above 30°C, which coincided with decreased membrane fluidity of bovine spermatozoa in this temperature range. The critical osmolality at 22°C, at which half of the sperm population survived exposure to hypotonic saline solution, was found to vary between 55 and 170 mOsm kg–1 among different stallions. Clear correlations were found for pre- versus post-freeze sperm motility and membrane integrity. Pre-freeze percentages of membrane-intact spermatozoa after exposure to hypotonic stress showed a weak correlation with sperm motility after cryopreservation. This correlation, however, was not found when data were corrected for initial numbers of membrane-intact spermatozoa in the sample. We thus conclude that studies on pre-freeze tolerance towards hypotonic stress cannot be used to predict sperm cryosurvival rates for individual stallions.

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Vascular endothelial wound closure under shear stress: role of membrane fluidity and flow-sensitive ion channels

Journal of Applied Physiology ◽

10.1152/japplphysiol.01136.2004 ◽

2005 ◽

Vol 98 (6) ◽

pp. 2355-2362 ◽

Cited By ~ 41

Author(s):

Andrea Gojova ◽

Abdul I. Barakat

Keyword(s):

Shear Stress ◽

Cell Migration ◽

Ion Channels ◽

Membrane Fluidity ◽

Wound Closure ◽

Fluid Dynamic ◽

Cell Spreading ◽

Rapid Healing ◽

Static Conditions

Sufficiently rapid healing of vascular endothelium following injury is essential for preventing further pathological complications. Recent work suggests that fluid dynamic shear stress regulates endothelial cell (EC) wound closure. Changes in membrane fluidity and activation of flow-sensitive ion channels are among the most rapid endothelial responses to flow and are thought to play an important role in EC responsiveness to shear stress. The goal of the present study was to probe the role of these responses in bovine aortic EC (BAEC) wound closure under shear stress. BAEC monolayers were mechanically wounded and subsequently subjected to either “high” (19 dyn/cm2) or “low” (3 dyn/cm2) levels of steady shear stress. Image analysis was used to quantify cell migration and spreading under both flow and static control conditions. Our results demonstrate that, under static conditions, BAECs along both wound edges migrate at similar velocities to cover the wounded area. Low shear stress leads to significantly lower BAEC migration velocities, whereas high shear stress results in cells along the upstream edge of the wound migrating significantly more rapidly than those downstream. The data also show that reducing BAEC membrane fluidity by enriching the cell membrane with exogenous cholesterol significantly slows down both cell spreading and migration under flow and hence retards wound closure. Blocking flow-sensitive K and Cl channels reduces cell spreading under flow but has no impact on cell migration. These findings provide evidence that membrane fluidity and flow-sensitive ion channels play distinct roles in regulating EC wound closure under flow.

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