Stimulation of chloride transport by fatty acids in corneal epithelium and relation to changes in membrane fluidity

Lipoxygenases are widespread enzymes that catalyze oxidation of polyunsaturated fatty acids (linoleic, linolenic, and arachidonic acid) to produce hydroperoxides. Lipoxygenase reactions can be desirable, but also lipoxygenases can react in undesirable ways. Most of the products of lipoxygenase reactions are aromatic compounds that can affect food properties, especially during long-term storage. Lipoxygenase action on unsaturated fatty acids could result in off-flavor/off-odor development, causing food spoilage. In addition, lipoxygenases are present in the human body and play an important role in stimulation of inflammatory reactions. Inflammation is linked to many diseases, such as cancer, stroke, and cardiovascular and neurodegenerative diseases. This review summarized recent research on plant families and species that can inhibit lipoxygenase activity.

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Stimulation of the Neutral Activity of Rabbit Liver Fructose 1,6-Diphosphatase by Fatty Acids

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)45307-6 ◽

1972 ◽

Vol 247 (9) ◽

pp. 2969-2971 ◽

Cited By ~ 1

Author(s):

Robert C. Baxter ◽

Charles W. Carlson ◽

Burton M. Pogell

Keyword(s):

Fatty Acids ◽

Rabbit Liver ◽

Neutral Activity ◽

Stimulation Of

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Investigation of the Membrane Fluidity Regulation of Fatty Acid Intracellular Distribution by Fluorescence Lifetime Imaging of Novel Polarity Sensitive Fluorescent Derivatives

International Journal of Molecular Sciences ◽

10.3390/ijms22063106 ◽

2021 ◽

Vol 22 (6) ◽

pp. 3106

Author(s):

Giada Bianchetti ◽

Salome Azoulay-Ginsburg ◽

Nimrod Yosef Keshet-Levy ◽

Aviv Malka ◽

Sofia Zilber ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Free Fatty Acids ◽

Membrane Fluidity ◽

Fluorescence Lifetime ◽

Intracellular Distribution ◽

Fluorescence Lifetime Imaging ◽

Lifetime Imaging ◽

Fatty Acid Derivatives ◽

Polarity Sensitive

Free fatty acids are essential structural components of the cell, and their intracellular distribution and effects on membrane organelles have crucial roles in regulating the metabolism, development, and cell cycle of most cell types. Here we engineered novel fluorescent, polarity-sensitive fatty acid derivatives, with the fatty acid aliphatic chain of increasing length (from 12 to 18 carbons). As in the laurdan probe, the lipophilic acyl tail is connected to the environmentally sensitive dimethylaminonaphthalene moiety. The fluorescence lifetime imaging analysis allowed us to monitor the intracellular distribution of the free fatty acids within the cell, and to simultaneously examine how the fluidity and the microviscosity of the membrane environment influence their localization. Each of these probes can thus be used to investigate the membrane fluidity regulation of the correspondent fatty acid intracellular distribution. We observed that, in PC-12 cells, fluorescent sensitive fatty acid derivatives with increased chain length compartmentalize more preferentially in the fluid regions, characterized by a low microviscosity. Moreover, fatty acid derivatives with the longest chain compartmentalize in lipid droplets and lysosomes with characteristic lifetimes, thus making these probes a promising tool for monitoring lipophagy and related events.

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The regulation of glyceride synthesis in isolated white-fat cells. The effects of palmitate and lipolytic agents

Biochemical Journal ◽

10.1042/bj1281057 ◽

1972 ◽

Vol 128 (5) ◽

pp. 1057-1067 ◽

Cited By ~ 31

Author(s):

E. D Saggerson

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Free Fatty Acids ◽

Fatty Acid Synthesis ◽

Acid Synthesis ◽

Fat Cells ◽

Glyceride Synthesis ◽

Glucose Incorporation ◽

High Concentrations ◽

Stimulation Of

1. 0.5mm-Palmitate stimulated incorporation of [U-14C]glucose into glyceride glycerol and fatty acids in normal fat cells in a manner dependent upon the glucose concentration. 2. In the presence of insulin the incorporation of 5mm-glucose into glyceride fatty acids was increased by concentrations of palmitate, adrenaline and 6-N-2′-O-dibutyryladenosine 3′:5′-cyclic monophosphate up to 0.5mm, 0.5μm and 0.5mm respectively. Higher concentrations of these agents produced progressive decreases in the rate of glucose incorporation into fatty acids. 3. The effects of palmitate and lipolytic agents upon the measured parameters of glucose utilization were similar, suggesting that the effects of lipolytic agents are mediated through increased concentrations of free fatty acids. 4. In fat cells from 24h-starved rats, maximal stimulation of glucose incorporation into fatty acids was achieved with 0.25mm-palmitate. Higher concentrations of palmitate were inhibitory. In fat cells from 72h-starved rats, palmitate only stimulated glucose incorporation into fatty acids at high concentrations of palmitate (1mm and above). 5. The ability of fat cells to incorporate glucose into glyceride glycerol in the presence of palmitate decreased with increasing periods of starvation. 6. It is suggested that low concentrations of free fatty acids stimulate fatty acid synthesis from glucose by increasing the utilization of ATP and cytoplasmic NADH for esterification of these free fatty acids. When esterification of free fatty acids does not keep pace with their provision, inhibition of fatty acid synthesis occurs. Provision of free fatty acids far in excess of the esterification capacity of the cells leads to uncoupling of oxidative phosphorylation and a secondary stimulation of fatty acid synthesis from glucose.

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