No abstract available.
Pneumonia* ; Squalene

No abstract available.
Pneumonia* ; Squalene*

Squalen, a compound detected in olive oil, had an activity against coloileal cancer due to azoxymethan in rats and lung cancer due to nitrosamin in mice. Squalen is a mediate substance in biosynthesis of mevaloat/cholesterol. Squalen is synthetised by catalysis squalen syntherase but it inhibits this enzyme which lead the reverse inhibition of HMG-CoA reductase to reduce the first stage of cholesterol synthesis. The more important outcome was that squalen inhibits protein transferees, which is an enzyme that is necessary for farnesrylization of rasprotein causing cancer
Squalene ; neoplasms

Triterpenoids are a class of natural products of great commercial value that are widely used in pharmaceutical, health care and cosmetic industries. The biosynthesis of triterpenoids relies on the efficient synthesis of squalene epoxide, which is synthesized from the NADPH dependent oxidation of squalene catalyzed by squalene epoxidase. We screened squalene epoxidases derived from different species, and found the truncated squalene epoxidase from Rattus norvegicus (RnSETC) showed the highest activity in engineered Escherichia coli. Further examination of the effect of endogenous cytochrome P450 reductase like (CPRL) proteins showed that overexpression of NADH: quinone oxidoreductase (WrbA) under Lac promoter in a medium-copy number plasmid increased the production of squalene epoxide by nearly 2.5 folds. These results demonstrated that the constructed pathway led to the production of squalene epoxide, an important precursor for the biosynthesis of triterpenoids.
Animals ; Escherichia coli/genetics* ; NADPH-Ferrihemoprotein Reductase ; Protein Engineering ; Rats ; Repressor Proteins ; Squalene ; Squalene Monooxygenase/genetics*

No abstract available.
Foreign Bodies* ; Foreign-Body Reaction ; Granuloma ; Granuloma, Foreign-Body* ; Squalene*

Exogenous lipoid pneumonia is an uncommon disease that's caused by aspirating lipid formulations. Squalene, obtained from shark liver oil, is one of the causative agent and this is commonly used by some Koreans as a health promoting medication. We report here on a case of exogenous lipoid pneumonia that developed after ingestion of squalene capsules. The case showed milky BAL fluid and multiple pulmonary consolidations.
Bronchoalveolar Lavage Fluid ; Capsules ; Eating ; Liver ; Pneumonia ; Sharks ; Squalene

Squalene is widely used in pharmaceutical, nutraceutical, cosmetics and other fields because of its strong antioxidative, antibacterial and anti-tumor activities. In order to produce squalene, a gene ispA encoding farnesyl pyrophosphate synthase was overexpressed in a previously engineered Escherichia coli strain capable of efficiently producing terpenoids, resulting in a chassis strain that efficiently synthesizes triterpenoids. Through phylogenetic analysis, screening, cloning and expression of squalene synthase derived from different prokaryotes, engineered E. coli strains capable of efficiently producing squalene were obtained. Among them, squalene produced by strains harboring squalene synthase derived from Thermosynechococcus elongatus and Synechococcus lividus reached (16.5±1.4) mg/g DCW ((167.1±14.3) mg/L broth) and (12.0±1.9) mg/g DCW ((121.8±19.5) mg/L broth), respectively. Compared with the first-generation strains harboring the human-derived squalene synthase, the squalene synthase derived from T. elongatus and S. lividus remarkably increased the squalene production by 3.3 times and 2.4 times, respectively, making progress toward the cost-effective heterologous production of squalene.
Cloning, Molecular ; Escherichia coli/genetics* ; Humans ; Phylogeny ; Squalene ; Synechococcus

Triterpenoids are one of the most diverse compounds in plant metabolites, and they have a wide variety of physiological activities and are of important economic value. Oxidosqualene cyclases catalyze the cyclization of 2, 3-oxidosqualene to generate different types of sterols and plant triterpenoids, which is of great significance to the structural diversity of natural products. However, the mechanism of the diversified cyclization of 2, 3-oxidosqualene catalyzed by oxidosqualene cyclases remains unclear. This review summarized the research progress of oxidosqualene cyclases from the aspects of catalytic function, molecular evolutionary relationship between genes and proteins, protein structure, molecular simulation and molecular calculations, which may provide a reference for protein engineering and metabolic engineering of triterpene cyclase.
Intramolecular Transferases/metabolism* ; Metabolic Engineering ; Plants/genetics* ; Squalene/chemistry* ; Triterpenes

BACKGROUND: The changes in lipid composition during epidermal differentiation has been reported in human and animal models. Because of the difficulties in getting adeguate specimens from human subjects, the authors used easily obtainable circumcised prepuce for lipid analysis. OBJECTIVE: To investigate the changes in lipid composition duriig cornification of the epidermis, the lipid compositions of whole epidermis and stratum corneum were analyzed by thin layer chromatography(TLC). METHODS: From circumcied prepuce whole epidermis and stratum orneum were separated by 10mM EDTA(ethylene diamine tatraacetate) in PBS(phosphate-buffered saline) or heat(60C), and 0.5% trypsin in PBS respectively. Lipids were extracted with methanolctloroform-HO mixture(4:2:1.6, v/ v, Bligh-Dyer solvent), TLC was performed and lipid composition was quantitated by photodensitometer. RESULTS: In the composition of stratum corneum lipids, sphingoliids were the highest(33.3+2.9%) followed by cholesterol, free fatty acids and cholesterol esters in cleceasing order, there were small percentages of triglycerides, cholesterol sulfate and squalene. CONCLUSION: In this study the lipid composition of epidermis was similar to that of stratum corneum rather than those of previous reports on epidermal lipids, which may indicate the regional characteristics of epidermal/stratum orneum lipids in hyperkeratotic prepuie.
Cholesterol ; Cholesterol Esters ; Epidermis* ; Fatty Acids, Nonesterified ; Humans ; Models, Animal ; Squalene ; Triglycerides ; Trypsin

Oil granuloma develops mainly after injection of oil substances such as paraffin, silicone, etc, but there have been reports of oil granuloma after topical application of lipid substance to the body. A 22-year-old woman developed oil granuloma after the application of squalene on both lower eye-lids. Histopathologic findings ahowed acanthosis and dyskeratosis of the hair follicles. Lipid suketances staining with oil-red-O stain were found mainly on the hair follicles. and partly on the epidermis. We report a case of oil grinulorna caused by squalerie that may have penetrated through the hair follicles and partly through the epidermis resulting in chronic granulous changes in the dermis.
Dermis ; Epidermis ; Eyelids* ; Female ; Granuloma* ; Hair Follicle ; Humans ; Paraffin ; Silicones ; Squalene* ; Young Adult