scholarly journals Effect of Cholesterol on Liposome Stability to Ultrasonic Disintegration and Sodium Cholate Solubilization

1987 ◽  
Vol 35 (3) ◽  
pp. 1228-1233 ◽  
Author(s):  
TOSHIHISA YOTSUYANAGI ◽  
HOTAKA HASHIMOTO ◽  
MOTOKAZU IWATA ◽  
KEN IKEDA
Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1023
Author(s):  
Ji Young Yu ◽  
Piyanan Chuesiang ◽  
Gye Hwa Shin ◽  
Hyun Jin Park

Liposomes have been utilized as a drug delivery system to increase the bioavailability of drugs and to control the rate of drug release at the target site of action. However, the occurrence of self-aggregation, coalescence, flocculation and the precipitation of aqueous liposomes during formulation or storage can cause degradation of the vesicle structure, leading to the decomposition of liposomes. To increase the stability of liposomes, post-processing techniques have been applied as an additional process to liposomes after formulation to remove water and generate dry liposome particles with a higher stability and greater accessibility for drug administration in comparison with aqueous liposomes. This review covers the effect of these techniques including freeze drying, spray drying and spray freeze drying on the stability, physicochemical properties and drug encapsulation efficiency of dry liposomes. The parameters affecting the properties of liposomes during the drying process are also highlighted in this review. In addition, the impact of using a protective agent to overcome such limitations of each process is thoroughly discussed through various studies.


Soft Matter ◽  
2021 ◽  
Author(s):  
Meng Sun ◽  
Qintang Li ◽  
Xiao Chen

Luminescent gels have been successfully fabricated through the self-assembly of sodium cholate and a europium ion in choline chloride-based deep eutectic solvents.


1992 ◽  
Vol 292 (1) ◽  
pp. 62-69 ◽  
Author(s):  
Masanori Yonaha ◽  
Yoshiko Tampo ◽  
Wendy Clarke ◽  
Harold W. Davis ◽  
John B. Schenkman

2006 ◽  
Vol 27 (8) ◽  
pp. 1099-1111 ◽  
Author(s):  
M. Vinceković ◽  
D. Jurašin ◽  
V. Tomašić ◽  
M. Bujan ◽  
N. Filipović‐Vinceković

1978 ◽  
Vol 234 (6) ◽  
pp. E606
Author(s):  
J G Spenney

Acetylsalicylic acid hydrolase activity of rabbit fundic gastric mucosa has been isolated from the soluble 100,000 X g supernate. The enzymatic activity was partially purified by ammonium sulfate precipitation. The Km for acetylsalicylate was 2 mM and pH optimum was 8.6. The activity was insensitive to ionic strength, slightly inhibited by inclusion of 100 mM Cl-, and demonstrated no requirement for Ca2+ or Mg2+. Acetylsalicylic acid esterase was markedly inhibited by sodium cholate and sodium dodecyl sulfate. The enzyme was insensitive to sulfhydryl reagents with the exception of p-chloromercuribenzenesulfonic acid, which markedly inhibited the enzyme. Diisopropyl fluorophosphate (DFP) inhibited enzymatic activity with a Ki of 9 X 10(-9)M. Eserine was also inhibitory with a Ki of 0.25 mM. Inhibition by DFP at low concentration and by eserine at millimolar concentrations suggests that this enzyme is related to the group of aliphatic esterases. Identification of potent inhibitors will enable studies to define the role of this enzyme with the use of experimental preparations in which systemic toxicity can be avoided.


1970 ◽  
Vol 44 (1) ◽  
pp. 35-56 ◽  
Author(s):  
M. J. Howell

1. Metacercarial cysts of Echinoparyphium serratum occur in the pericardium of the snail Isidorella brazieri. Each cyst is surrounded by a nucleated, syncytial host capsule containing granules which are presumed to be melanin. The cyst wall consists of two layers and both contain acid and neutral mucopolysaccharide but little or no protein. No modification of the cyst wall coincident with the point of emergence of the metacercaria has been located.2. Excystment of the metacercaria takes place in two main stages when pepsin is omitted from the initial pretreatment solution: stage I (emergence from the cyst wall through the escape aperture) is an active process (exogenous enzymes are not necessary), and a high percentage of specimens reaching this stage is dependent on the combined effects of a þH of 2, reducing conditions, elevated temperature (37–39°C) and sodium cholate. Temperature and sodium cholate are absolute requirements for this stage as is pretreatment of between þH 2 and 4 when sodium cholate is included with the reductant (sodium dithionite) rather than in the excystment medium with trypsin. The possibility that CO2 is involved has not been established.


Pharmaceutics ◽  
2018 ◽  
Vol 10 (4) ◽  
pp. 172 ◽  
Author(s):  
E. Danielsen ◽  
Gert Hansen

The small intestinal epithelium constitutes a major permeability barrier for the oral administration of therapeutic drugs with poor bioavailability, and permeation enhancers (PEs) are required to increase the paracellular and/or transcellular uptake of such drugs. Many PEs act as surfactants by perturbing cell membrane integrity and causing permeabilization by leakage or endocytosis. The aim of the present work was to study the action of sodium cholate (NaC) and N-dodecyl-β-D-maltoside (DDM), using a small intestinal mucosal explant system. At 2 mM, both NaC and DDM caused leakage into the enterocyte cytosol of the fluorescent probe Lucifer Yellow, but they also blocked the constitutive endocytotic pathway from the brush border. In addition, an increased paracellular passage of 3-kDa Texas Red Dextran into the lamina propria was observed. By electron microscopy, both PEs disrupted the hexagonal organization of microvilli of the brush border and led to the apical extrusion of vesicle-like and amorphous cell debris to the lumen. In conclusion, NaC and DDM acted in a multimodal way to increase the permeability of the jejunal epithelium both by paracellular and transcellular mechanisms. However, endocytosis, commonly thought to be an uptake mechanism that may be stimulated by PEs, was not involved in the transcellular process.


1997 ◽  
Vol 273 (1) ◽  
pp. E37-E45 ◽  
Author(s):  
S. Ikemoto ◽  
M. Takahashi ◽  
N. Tsunoda ◽  
K. Maruyama ◽  
H. Itakura ◽  
...  

The effects of sodium cholate on high-fat diet-induced hyperglycemia and obesity were investigated. Insulin resistance was estimated by measuring 2-deoxyglucose uptake in epitrochlearis muscles incubated in vitro. Addition of 0.5% cholate to high-safflower oil diet completely prevented high fat-induced hyperglycemia and obesity in C57BL/6J mice with a slight decrease of energy intake but with no inhibition of fat absorption. Furthermore, the addition of cholate decreased blood insulin levels and prevented high-fat diet-induced decrease of glucose uptake in epitrochlearis. However, there was no change in the unsaturation index of fatty acids in skeletal muscles and in GLUT-4 levels by cholate. In liver, cholate addition resulted in cholesterol accumulation and completely prevented high-fat diet-induced triglyceride accumulation. The changes of triglyceride level in the liver were paralleled to the changes of acyl-CoA synthetase (ACS) mRNA. ACS catalyzes the formation of acyl-CoA from fatty acid, and acyl-CoA is utilized for triglyceride formation in liver. ACS has a sterol-responsive element 1 in its promoter region. These data indicate that the favorable effects of cholate could be partly the result of downregulation of ACS mRNA.


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