Phospholipid homeostasis

The control of the processes of phosphohpid translocation and scrambling by cytoplasmic calcium concentration is known to be one factor in regulating the appearance of phosphatidylserine on the cell surface. There is now evidence that other factors are involved in modulating membrane phospholipid distribution and for preserving phospholipid homeostasis. Current research is directed to clarify the role of these agents and to establish any connections with the initiation of apoptosis. 

ATP-binding cassette transporter ABCAl (member 1 of human transporter subfamily ABCA) ABCAl is a human protein and gene. This transporter is a major regulator of cellular cholesterol and phospholipids homeostasis. ABCAl functions as a cholesterol efflux pump in the cellular lipid removal pathway. 

Sakaida I, Thomas AP, Farber JL. 1992. Phospholipid metabolism and intracellular Ca2+ homeostasis in cultured rat hepatocytes intoxicated with cyanide. Am J Physiol 263(3 Pt 1) C684-C690. 

Diethanolamine is metabolized by biosynthetic routes common to endogenous alkanolamines (ethanolamine and choline) and incorporated into phospholipids. It is excreted predominantly unchanged with a half-life of approximately one week in urine. In the absence of sodium nitrite, no conversion to TV-nitrosodiethanolamine is observed. Diethanolamine competitively inhibits the cellular uptake of choline in vitro and hepatic changes in choline homeostasis, consistent with choline deficiency, are observed in vivo. 

Mechanism of Action. Like the systemic azoles, clotrimazole and other topical antifungal azoles work by inhibiting the synthesis of key components of the fungal cell membrane that is, these drugs impair production of membrane sterols, triglycerides, and phospholipids.9 Loss of these components results in the membrane s inability to maintain intracellular homeostasis, leading to death of the fungus. 

Mao-Qiang, M. et al., Extracellular processing of phospholipids is required for permeability barrier homeostasis, J. Lipid Res., 36, 1925, 1995. 

The larger biomolecules that have potential Al3+ binding sites are phosphate-bearing biomolecules such as ATP, membrane phospholipids and nucleic acids. It is important to recognize that the metal coordination of these biomolecules might lead to serious disgorges in central biological processes necessary to cell homeostasis and consequently for its overall healthy condition [21]. 

The liver is central to both lipid and lipoprotein metabolism and homeostasis. There are three major plasma lipids cholesterol, phospholipids and triglycerides. All are highly insoluble in water. 

While cyanide inhibition of cytochrome c oxidase may not account for the full spectrum of toxicity in CS exposure, cyanide toxicity may include an array of biochemical interactions (Way, 1984). These include lipid peroxidation (Johnson et al, 1987), cyanide release of endogenous opioids to cause respiratory paralysis (Leung et al, 1986), disruption of neuronal calcium homeostasis (Johnson et al, 1986), and phospholipids hydrolysis (Sakaida and Farber,... 

Butyl ether has the ability to dissolve lipids. As a result, it may cause irritation and pain upon contact with eyes and nose mucosa. It also causes dermal irritation and dermatitis upon contact with the skin. Damage caused by butyl ether appears to be scattered loss of epithelial cells due to dissolution of phospholipid cell membranes. At the CNS level, butyl ether, like other volatile organic solvents, depresses the CNS by dissolving in the cell lipid membrane and disrupting the lipid matrix. These effects are known as membrane fluidization. At the molecular level, membrane fluidization disrupts solute gradient homeostasis that is essential for cell function. 

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